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Research ArticleCHEMICAL PHYSICS
Classical strong metal–support interactions between gold nanoparticles and titanium dioxide
Hailian Tang1,2,3,
Yang Su1,
Bingsen Zhang4,
Adam F. Lee5,
Mark A. Isaacs5,
Karen Wilson5,
Lin Li1,
Yuegong Ren1,3,6,
Jiahui Huang1,6,
Masatake Haruta1,6,7,
Botao Qiao1,*,
Xin Liu1,
Changzi Jin1,2,
Dangsheng Su1,4,
Junhu Wang1,2,* and
Tao Zhang1,2,3
1State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
2Mössbauer Effect Data Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
3University of Chinese Academy of Sciences, Beijing 100049, China.
4Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China.
5European Bioenergy Research Institute, Aston University, Aston Triangle, Birmingham B4 7ET, UK.
6Gold Catalysis Research Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
7Research Center for Gold Chemistry and Department of Applied Chemistry, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University, Tokyo 192-0397, Japan.
↵*Corresponding authors. Email: bqiao{at}dicp.ac.cn (B.Q.); wangjh{at}dicp.ac.cn (J.W.)
Science Advances 13 Oct 2017:
Vol. 3, no. 10, e1700231
Hailian Tang
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.Mössbauer Effect Data Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.University of Chinese Academy of Sciences, Beijing 100049, China.
ORCID record for Hailian Tang
Yang Su
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Bingsen Zhang
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China.
Adam F. Lee
European Bioenergy Research Institute, Aston University, Aston Triangle, Birmingham B4 7ET, UK.
ORCID record for Adam F. Lee
Mark A. Isaacs
Karen Wilson
Lin Li
Yuegong Ren
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.University of Chinese Academy of Sciences, Beijing 100049, China.Gold Catalysis Research Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Jiahui Huang
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.Gold Catalysis Research Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Masatake Haruta
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.Gold Catalysis Research Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.Research Center for Gold Chemistry and Department of Applied Chemistry, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University, Tokyo 192-0397, Japan.
Botao Qiao
For correspondence: bqiao@dicp.ac.cn wangjh@dicp.ac.cn
Xin Liu
Changzi Jin
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.Mössbauer Effect Data Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Dangsheng Su
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China.
Junhu Wang
ORCID record for Junhu Wang
Tao Zhang
Supported metal catalysts play a central role in the modern chemical industry but often exhibit poor on-stream stability. The strong metal–support interaction (SMSI) offers a route to control the structural properties of supported metals and, hence, their reactivity and stability. Conventional wisdom holds that supported Au cannot manifest a classical SMSI, which is characterized by reversible metal encapsulation by the support upon high-temperature redox treatments. We demonstrate a classical SMSI for Au/TiO2, evidenced by suppression of CO adsorption, electron transfer from TiO2 to Au nanoparticles, and gold encapsulation by a TiOx overlayer following high-temperature reduction (reversed by subsequent oxidation), akin to that observed for titania-supported platinum group metals. In the SMSI state, Au/TiO2 exhibits markedly improved stability toward CO oxidation. The SMSI extends to Au supported over other reducible oxides (Fe3O4 and CeO2) and other group IB metals (Cu and Ag) over titania. This discovery highlights the general nature of the classical SMSI and unlocks the development of thermochemically stable IB metal catalysts.
Supported metal catalysts, comprising metal particles finely dispersed on high–surface area materials, are the most widespread form of heterogeneous catalysts (1–3). They play a central role in the modern chemical industry, and, hence, are of vital importance to the global economy (4). The principal role of the support was initially ascribed to stabilization of the active component and/or increase in the metal dispersion and surface area (5, 6). However, it was soon realized that physicochemical interactions between the metal and the support can also influence catalytic performance through so-called carrier effects (1, 5). These metal-support interactions have a long history of controlling catalyst structure and reactivity (7).
A specific form of these carrier effects came to prominence in the late 1970s, where an unusual interaction was observed between platinum group metals (PGMs) and TiO2, which markedly suppressed small-molecule (such as CO and H2) adsorption following high-temperature reduction (HTR) treatments. This discovery by Tauster et al. (8) was termed the strong metal–support interaction (SMSI; now referred to as classical SMSI). Subsequently, SMSI effects have been the subject of intensive study (9–12). Although suppressed H2 and CO adsorption was initially ascribed to electronic perturbation of the PGM atoms by interaction with Ti cations (8), a consensus has now been reached that this SMSI effect originates from metal encapsulation by a titania overlayer (11, 13). Induction of the SMSI markedly modifies catalytic performance in diverse reactions (11, 14–16) and has been exploited to improve catalyst stability (17–19), identify reaction mechanisms (20, 21), and enhance activity (14, 22). Consequently, research into catalyst systems that can manifest SMSI effects has undergone rapid expansion (15). However, to date, classical SMSI has never been reported for Au/TiO2 catalysts, and there is only one such example where SMSI has been inferred for any group IB metal based on x-ray photoelectron spectroscopy (XPS) and ion-scattering spectroscopy (ISS) measurements of Ag/TiO2 (23).
Oxide-supported gold catalysts have attracted global attention in recent decades, with Au/TiO2 probably the most extensively investigated (6, 24–26). Supported Au catalysts have shown promise for several industrial processes because of their unique catalytic performance, including a new commercial process for vinyl chloride monomer production (27); however, practical applications have been hindered by poor on-stream stability (28, 29). The genesis of an SMSI between Au and titania would offer a route to stabilize Au nanoparticles (NPs) (18, 19), but surface science studies of model catalysts have found no evidence for this phenomenon (30–32). Although Goodman (33) noted electron transfer between Au and TiO2 upon reduction, this was accompanied by increased CO adsorption, contrary to classical SMSI. Au NPs are not believed to undergo SMSI with titania (34, 35), variously attributed to gold's relatively low work function and surface energy compared with other noble metals (31, 36) or (supposed) inability to dissociate molecular hydrogen and thus initiate titania reduction and subsequent oxide migration to the metal surface. However, recent theoretical and experimental studies demonstrate that gold can dissociate H2 and, hence, potentially promote the reduction of oxide supports (37–39); there is no scientific basis for the notion that Au/TiO2 should not exhibit an SMSI.
Progress on practical catalyst systems has uncovered an O2-induced SMSI for gold supported on ZnO nanorods (40) and hydroxyapatite (18, 19), the reverse of conditions required for classical SMSI. However, decreased CO adsorption was reported following the reduction of Au/CeO2 (41), hinting at the existence of classical SMSI effects in gold catalysis. Here, we report the unequivocal discovery of a classical SMSI in Au/TiO2, evidenced by encapsulation of gold particles by partially reduced titania and accompanied by suppressed CO adsorption and enhanced catalytic stability for CO oxidation. The SMSI extends to Au supported over other reducible oxide supports and other group IB metals (Cu and Ag) over titania. For Au/TiO2, titania reduction is identified as critical for inducing the SMSI state. This finding highlights the generality of the classical SMSI phenomena and associated difficulties that arise when seeking parallels between surface science and practical catalyst studies (due to pressure and material gaps), and unlocks new opportunities to design thermally stable, supported group IB metal catalysts.
The Au/TiO2 sample of RR2Ti was supplied by Haruta Gold Inc. and denoted as RR2Ti-fresh. It was subsequently reduced under 10 volume % H2/He flow at temperatures between 200° and 500°C for 1 hour, and each was denoted as RR2Ti-HX (X, the reduction temperature). The RR2Ti-H500 sample was also reoxidized under 10 volume % O2/He flow at 400°C for 1 hour and denoted as RR2Ti-(H500+O400).
The main characteristics of classical SMSI following HTR are (i) the significant suppression of small-molecule adsorption (such as CO and H2), (ii) electron transfer from the support to metal resulting in a negatively charged metal species, (iii) mass transport from the support to encapsulate metal NPs with a thin overlayer of the support materials, and (iv) a reversal of the preceding phenomena upon reoxidation. Each of these characteristics is evidenced below.
Fourier transform infrared study of CO adsorption
The mean diameters of Au NPs within the RR2Ti-HX (X = 200 to 500) family determined by high-resolution transmission electron microscopy (HRTEM) were 4.8 to 5.2 nm (fig. S1), which were only slightly larger than the mean diameter of the RR2Ti-fresh sample (4.1 nm). These values were consistent with the x-ray powder diffraction (XRD) (fig. S2A) result, where the diffractogram of RR2Ti-H500 is similar to that of RR2Ti-fresh, with no reflections due to any gold phase visible and a common ratio of anatase (101)/rutile (110) reflections. Together, these show that neither Au NP size nor TiO2 phase composition was influenced by HTR treatments. This is in line with the previous study on a real catalyst (34) but is in contrast to surface studies on model catalysts (42, 43), suggesting that the interaction between gold and TiO2 during ambient pressure reduction over inhomogeneous catalysts differs from that under ultrahigh vacuum over single crystals. These observations also show that the RR2Ti samples provide an excellent testing ground for exploring Au NP and support interactions because possible particle size and titania phase differences between samples before and after HTR are minimal.
The suppression of chemisorption of small molecules on metals and electron transfer between metals and supports following HTR are the primary characteristics of SMSI. In situ diffuse reflectance infrared (IR) Fourier transform spectroscopy (DRIFTS) was therefore used to explore both effects because this technique is sensitive to both adsorption and electronic properties of metal surfaces with a suitable probe molecule (18, 19). Figure 1 shows the DRIFTS of CO adsorption on RR2Ti catalysts as a function of various pretreatments. Three bands at 2175, 2120, and 2103 cm−1 are observed for the RR2Ti-fresh sample. The first two are attributed to gaseous CO, and the latter is attributed to CO adsorbed on metallic Au (CO-Au0) (44). The CO-Au0 band intensity decreased monotonically with increasing reduction temperature and disappeared after a 500°C reduction, evidencing a loss in CO adsorption sites over gold precisely as anticipated for classical SMSI, where H2 and CO adsorption are markedly suppressed (8, 45). Although this decreased CO adsorption has been occasionally reported for Au NPs (41), complete loss of CO adsorption capacity has never been observed to our knowledge. Because the Au NP dimensions for all Au/TiO2 samples are similar (figs. S1 and S2A), the loss of CO adsorption cannot arise from a change in the gold dispersion. This conclusion is supported by the observation that CO adsorption was recovered for RR2Ti-(H500+O400) (which had a similar Au NP size distribution; fig. S1F) obtained from in situ O2 treatment of RR2Ti-H500 at 400°C for 1 hour under 10 volume % O2/He. Note that the recovered CO adsorption is blue-shifted relative to that of RR2Ti-fresh, suggesting that surface Au species have a slight positive charge after oxidation. This indicates that the Au-TiO2 interaction after a redox cycle slightly differs from that in the fresh RR2Ti material; however, we show later that this interaction can be fully reversed under repeated redox cycling. It should also be noted that the RR2Ti-H400 material exhibited a new band around 2070 cm−1, ascribed to CO adsorbed on a negatively charged Au surface (CO-Aux−) (44). The existence of such a negative Au surface species evidences electron transfer from TiO2 to Au following a ≥400°C reduction, as observed for the classical SMSI in TiO2-supported PGMs. Additional insight into the electronic properties of the RR2Ti-fresh, RR2Ti-H500, and RR2Ti-(H500+O400) samples was obtained by XPS; this was especially important for the RR2Ti-H500 material for which no CO was adsorbed.
Fig. 1 In situ DRIFT spectra of CO adsorption over RR2Ti-fresh, RR2Ti-HX (X = 200 to 500), and RR2Ti-(H500+O400) samples.
a.u., arbitrary units.
XPS and EPR studies
Figure 2A shows that the binding energy of the Au 4f7/2 spin-orbit split component for RR2Ti-fresh was 83.5 eV, typical of metallic gold (19). The Au 4f7/2 shifted to 83.1 eV following a 500°C reduction, indicating the formation of electron-rich Au species and consistent with the RR2Ti-H400 DRIFT spectrum (Fig. 1). After a 400°C oxidation, the Au 4f7/2 shift was reversed, returning to 83.5 eV and demonstrating a return of the negatively charged Au species to the metallic state. Thus, XPS evidences reversible electron transfer between TiO2 and Au NPs under redox treatments. Although the latter observation appears at odds with CO DRIFTS, which indicates that surface Au species have a slight positive charge after oxidation, these IR measurements are more surface-sensitive than XPS (for Au 4f7/2 photoelectrons, the inelastic mean free path is ~1.3 nm), and hence, partially charged Auδ+ atoms likely only reside in the terminating layer of the NPs in direct contact with titania. No reduced Ti3+ species were observed in the corresponding Ti 2p XP spectra of these samples (fig. S3), in contrast to the case of TiO2-supported PGMs (30, 36), suggesting either a smaller magnitude of charge transfer from titania or smaller number of reduced TiOx species in our gold materials. Gold encapsulation by titania in the SMSI state following HTR should also decrease the Au/Ti surface ratio, and a 33% decrease was observed between the RR2Ti-fresh and RR2Ti-H500 samples. This decrease was reversed upon subsequent reoxidation at 400°C, with the Au/Ti surface ratio of RR2Ti-(H500+O400) returning to that of the fresh sample. This magnitude decrease is close to ~38% attenuation calculated for the complete encapsulation of Au NPs by a single monolayer of 0.7-nm-thick titania (46), assuming an inelastic mean free path of 1.45 nm for 1402-eV kinetic energy Au 4f7/2 electrons. The return of the Au/Ti surface ratio to its original value following reoxidation supports the idea that the reversible attenuation of gold XP signal resulted from a classical SMSI (metal encapsulation by a thin oxide overlayer following HTR, reversed upon subsequent oxidation). Evidence for Ti3+ species was thus explored by more sensitive electron paramagnetic resonance (EPR) measurements (47–49). Figure 2B shows that signals with g = 1.975, attributed to bulk Ti3+ defects (48, 50), were present in all samples. The RR2Ti-H500 sample exhibited a marked increase in this signal intensity by a factor of 6 to 7, coincident with the appearance of a new signal with g = 1.930, attributed to surface Ti3+ (51), highlighting a significant increase in overall Ti3+ species following HTR. Subsequent oxidation suppressed the g = 1.975 signal and eliminated the g = 1.930 signal, restoring the RR2Ti-fresh spectrum. Thus, EPR provides compelling evidence for TiO2 reduction after HTR and, hence, H2 dissociation and concomitant charge transfer from TiOx to Au, as expected for a classical SMSI.
Fig. 2 Electronic properties of RR2Ti samples.
(A) Au 4f XP spectra of RR2Ti-fresh, RR2Ti-H500, and RR2Ti-(H500+O400) samples. (B) EPR spectra of the RR2Ti-fresh, RR2Ti-H500, and RR2Ti-(H500+O400) samples obtained at 100 K.
HRTEM and EELS studies
The above results demonstrate the suppression of CO adsorption and accompanying electron transfer from TiO2 to Au after reduction at elevated temperatures (especially 500°C). This loss of CO adsorption capacity does not originate from a dispersion change, is reversible (most likely arising from the encapsulation of Au NPs by a thin overlayer of TiO2 support), and has never been reported previously (32, 33, 36), except under long-term electron irradiation in an environmental TEM (52). Potential gold encapsulation was therefore explored through HRTEM, as shown in Fig. 3. As expected, Au NPs in the RR2Ti-fresh samples were naked, but were covered with a thin layer of low-contrast material following subsequent reduction, where the overlayer coverage/thickness was proportional to the reduction temperature. For samples reduced at 200° and 300°C, naked and covered Au NPs coexist (Fig. 3, B and C, and corresponding insets), whereas for RR2Ti-H400 and RR2Ti-H500 samples, only encapsulated Au NPs were observed. Hence, in accordance with DRIFTS, we propose that all Au NPs in RR2Ti-H500 were completely encapsulated, and for RR2Ti-H400, either a small proportion of Au was not fully encapsulated or the encapsulating titania overlayer was not crystalline and remained gas-permeable (53). According to a classical SMSI, this overlayer would comprise TiOx species (with x < 2) (10, 54). The nature of the overlayer in RR2Ti-H500 was therefore probed by electron energy loss spectroscopy (EELS). Figure 3G and fig. S4 reveal clear Ti L-edge signals for all measured Au NPs, proving their coverage by a Ti-containing coating. Spectral fitting of Fig. 3G (shown in fig. S5) revealed the presence of two chemically distinct Ti species: those on the support (region III) characteristic of Ti4+ and those on Au NPs (region II) characteristic of Ti3+ species, consistent with recent reports (21, 53). In the case of the reoxidized RR2Ti-(H500+O400) sample (where CO chemisorption was restored), the thin overlayer has retreated, although not completely (Fig. 3F and fig. S6), in line with previous reports of classical SMSI for PGM catalysts (55–58).
Fig. 3 HRTEM images and EELS spectra.
(A to F) HRTEM images of (A) RR2Ti-fresh, (B) RR2Ti-H200, (C) RR2Ti-H300, (D) RR2Ti-H400, (E) RR2Ti-H500, and (F) RR2Ti-(H500+O400). (G) EELS spectra of the RR2Ti-H500 sample. Spectra were background-subtracted.
CO oxidation catalysis
One of the key features of classical SMSI behavior is that the aforementioned HTR phenomena are reversible upon O2 treatment, as is observed for RR2Ti-(H500+O400). For example, the restoration of CO adsorption for RR2Ti-(H500+O400) (Fig. 1) and HRTEM (Fig. 3F) evidences the reversibility of CO adsorption and gold encapsulation. XPS (Fig. 2A) and CO DRIFTS (band position) suggest that electron transfer between titania and gold is also reversible. The reversible nature of the classical SMSI effect following HTR and subsequent reoxidation is expected to strongly affect catalyst activity (18, 19, 40). The catalytic performance of the present Au/TiO2 samples was therefore assessed toward CO oxidation, an industrially important reaction for pollution abatement, over two cycles of redox treatments under a model CO/O2 feedstream and compared with analogous in situ CO DRIFTS measurements (Fig. 4). Suppressed CO chemisorption following HTR was mirrored by a marked decrease in CO conversion, with catalyst reoxidation restoring both CO adsorption capacity and oxidation activity, providing strong evidence for a reversible, classical SMSI in the commercial RR2Ti system (18, 40, 56).
Fig. 4 Reversibility of RR2Ti properties under redox treatment.
(A) In situ DRIFT spectra of CO adsorption over the RR2Ti-fresh sample following alternating pretreatment with 10 volume % H2/He at 500°C (for the first and third cycles) or 10 volume % O2/He at 400°C (for the second and fourth cycles) for 1 hour. (B) CO conversion at 80°C for the RR2Ti-fresh sample as a function of pretreatments described in (A). Reaction gas composition: 1 volume % CO + 1 volume % O2 balanced with He; gas flow rate, 33.3 ml/min; space velocity (SV), 64,452 ml gcat−1 hour−1.
The above unambiguously demonstrates that classical SMSI occurs in the commercial RR2Ti catalyst. To ascertain whether classical SMSI extended to related materials, we synthesized three Au/TiO2 catalysts using a deposition-precipitation method (59) and three popular forms of titania—P25 (Degussa), anatase, and rutile—as supports, as described in the Supplementary Materials. XRD (fig. S2, B to D) again confirmed the absence of significant Au NP size or titania phase differences within each catalyst family. In all cases, gold encapsulation (fig. S7) and the reversible suppression and recovery of CO chemisorption (fig. S8) following respective reductive and oxidation pretreatments indicate a common classical SMSI between Au NPs and these three titania supports, akin to that of RR2Ti. CO DRIFTS also highlights anatase as the most susceptible to encapsulation, followed by P25, with rutile as the least susceptible (showing only slightly suppressed CO adsorption). Similar observations were also obtained with 2- to 3-nm colloidal Au NPs on P25 (figs. S9 and S10), evidencing the generality of the SMSI following HTR of Au/TiO2 catalysts. Because the classical SMSI was caused by a reduction treatment, we hypothesized that this phenomenon may extend to other reducing gases, such as CO, at high temperature, and HRTEM and DRIFTS (fig. S11) confirmed that this high-temperature CO pretreatments of the RR2Ti catalyst induced reversible CO adsorption and Au NP encapsulation analogous to a classical SMSI effect.
The classical SMSI in PGM systems is not confined to titania and is reported over a range of reducible oxides (45). In light of this consideration, synthetic Au/Fe3O4 (prepared as described in the Supplementary Materials) and commercial Au/CeO2 (RR2Ce-2, supplied by Haruta Gold Inc.) were also subjected to similar H2 (HTR) and O2 redox protocols and characterized by XRD, HRTEM (figs. S12 and S13, respectively), and DRIFTS of chemisorbed CO (fig. S14). In both cases, neither Au NP size nor support phase exhibited significant changes following reduction or reoxidation, except for the appearance of a certain amount of Fe and α-Fe2O3, respectively, for the Au/Fe3O4 material. Reversible CO adsorption and gold encapsulation were again observed in both supports (figs. S14 and S15), similar to those seen in titania as detailed above, again evidencing a classical SMSI. Note that the threshold temperature for Au NP encapsulation of 500°C in the Au/CeO2 system is far lower than that for Pt/CeO2 and Rh/CeO2 (≥700°C) (58, 60), suggesting that, in some cases, classical SMSI is more facile in supported Au catalysts than in supported PGM catalysts.
The above results demonstrated that classical SMSI can occur in reducible oxide-supported Au catalysts. Grünert et al. (23) have previously inferred classical SMSI from surface-sensitive XPS and ISS spectroscopies for Ag/TiO2 catalysts for acrolein hydrogenation, although they did not visualize metal encapsulation, hinting that classical SMSI may extend to other IB metals. We therefore synthesized and investigated TiO2-supported Ag and Cu analogs in our Au/TiO2 systems. Figures S16 to S18 confirm that reversible CO adsorption and encapsulation of Ag NPs occurred following redox treatments, which were not attributable to particle size changes and hence classical SMSI between Ag NPs and TiO2. However, classical SMSI could not be induced for Cu/TiO2 by the same 500°C H2 reduction, where increased CO adsorption was observed (fig. S19): Corresponding EPR spectra (fig. S20) identified significant surface Ti3+ (g = 1.95) species for Ag/TiO2 but not for Cu/TiO2. Together, these results suggest that Cu is less effective in promoting TiO2 reduction, which is regarded as a prerequisite to induce an SMSI. The impact of IB metals on the reducibility of titania was further explored by temperature-programmed reduction (TPR). Figure S21 highlights only a weak HTR (804°C) for the parent TiO2 (P25), indicating minimal titania reduction. In contrast, RR2Ti-fresh exhibited a low-temperature (515°C) reduction, evidencing gold-promoted reduction of TiO2. For Cu/TiO2-fresh, this reduction shifted >700°C, indicating that Cu is a less efficient promoter of TiO2 reduction than gold but nonetheless still facilitates support reduction, and indicating that higher-temperature reduction protocols might induce an SMSI state for Cu/TiO2. To test this hypothesis, we reduced Cu/TiO2-fresh at 800°C and found complete suppression of CO adsorption (fig. S22); this could be partially reversed by subsequent 600°C oxidation. Considering that Cu can be totally oxidized to Cu2+ by calcination at 600°C and CO cannot be absorbed on Cu2+ (61), we in situ reduced the oxidized Cu/TiO2 at 200°C and discovered a significant CO adsorption. These results unambiguously demonstrate the occurrence of a high-temperature (800°C) SMSI for Cu/TiO2 and reaffirm that the reduction of surface Ti4+ is critical to induce the SMSI state (although other factors such as the surface energy/work function of metals may also play a role).
IB group metals, such as Au and Ag, are much less thermodynamically stable than PGMs when dispersed on supports and readily sinter at high temperature (28, 62). The general discovery of a classical SMSI between IB metals (Au, Ag, and Cu) and reducible oxides may facilitate the design and development of high-stability IB metal catalysts (18, 19). It is generally accepted that the low stability of supported Au catalysts has been a major challenge hindering their practical application (63), with previous studies indicating that an SMSI between Au and support could significantly improve their reaction stability (18, 19). We therefore explored whether the induction of a classical SMSI in Au/TiO2 could enhance catalyst stability toward CO oxidation, a key reaction in emission control systems, using a simulated mixture of 1.6 volume % CO, 1 volume % O2, 0.01 volume % propene, 0.0051 volume % toluene, and 10 volume % water balanced with He at 300°C; this relatively high temperature is expected to promote undesired sintering of Au NPs. For the RR2Ti-fresh catalyst, as expected, CO conversion decreased gradually during the 100-hour test, as shown in Fig. 5. High-angle annular dark field (HAADF)–scanning TEM (STEM) analysis of the fresh and used samples revealed the Au NPs sintered slightly during reaction (fig. S23). Control experiments show that deactivation of the RR2Ti-fresh catalyst was irreversible (fig. S24) and, hence, likely due to this sintering rather than the accumulation of surface carbonate (64, 65). In contrast, the RR2Ti-H400 sample, in which an SMSI operated, exhibited excellent stability, with negligible loss of CO oxidation activity throughout the test. To confirm that the excellent stability of the RR2Ti-H400 sample arose from the SMSI between Au and titania, the RR2Ti-H500 and RR2Ti-(H500+O400) samples were also explored for CO oxidation. Figure S25 shows that RR2Ti-H500 exhibited high stability (albeit a slightly lower activity) similar to the other HTR-treated sample, whereas the RR2Ti-(H500+O400) sample still underwent slow deactivation (albeit less than observed for the fresh sample). The latter findings are as expected because oxidation will reverse the SMSI, and hence, these treatments will be less effective in inhibiting Au NP sintering. Note that the 300°C reaction conditions did not reverse the SMSI in either RR2Ti-H400 or RR2Ti-H500 catalyst despite the net (slightly) oxidizing conditions, presumably reflecting the low O2 concentration (<1 volume %) and strong competitive adsorption of CO. The observation that the RR2Ti-H500 catalyst exhibits excellent activity for CO oxidation is, at first, surprising given its poor room temperature CO adsorption (Fig. 1). However, the work of several groups, including our own, have shown that complete encapsulation of Pt (66, 67) or Ir (68) by a reducible metal oxide (ceria), resulting in materials with very low CO titratable areas, produces a more active catalyst than the bare precious metal itself; metal-promoted oxygen vacancy formation in the oxide overlayer is postulated to markedly enhance reactivity.
Fig. 5 The CO conversion curves as a function of reaction time on the RR2Ti-fresh and RR2Ti-H400 samples tested at 300°C.
Reaction gas composition: 1.6 volume % CO, 1 volume % O2, 0.01 volume % propene, 0.0051 volume % toluene, and 10 volume % water balanced with He. For RR2Ti-H400: 40.5 mg of sample diluted with 120 mg of SiO2 powder; gas flow rate, 33.3 ml/min; SV, 49,000 ml gcat−1 min−1. For RR2Ti-fresh: 15.9 mg of sample diluted with 60 mg of SiO2 powder; gas flow rate, 33.3 ml/min; SV, 127,000 ml gcat−1 min−1.
In summary, we have shown the existence of a classical SMSI between Au and TiO2 that is relatively insensitive to the oxide phase (anatase or rutile) or reducing gas (H2 or CO) used to induce the SMSI. This classical SMSI extends to other reducible oxides, such as Fe3O4 and CeO2, and other titania-supported group IB group metals, such as Ag and even Cu. Genesis of the SMSI state in Au/TiO2 significantly enhances long-term catalyst stability toward CO oxidation. These discoveries may lead to a deeper understanding of the SMSI mechanism and its generalization to other transition metals, and unlock new design strategies for the development and operation of thermochemically stable supported group IB metal catalysts through precise engineering of the interaction between metal NPs and reducible oxide supports.
Sodium hydroxide (NaOH, 98%), anatase (TiO2, 99.8%), and rutile (TiO2, 99.8%) were purchased from Aladdin Company. Poly(vinyl alcohol) [PVA; molecular weight (Mw), 10,000; 80% hydrolyzed] was purchased from Aldrich. P25 (TiO2) was purchased from Evonik Degussa. Hydrogen terachloroaurate (IV) hydrate (HAuCl4·4H2O), ferroferric oxide (Fe3O4; 99.95%), sodium borohydride (NaBH4; 98%), silver nitrate (AgNO3; 99.8%), and copper(II) nitrate hemi(pentahydrate) [Cu(NO3)2·5H2O; 98%] were purchased from Alfa Aesar. The gold samples of RR2Ti and RR2Ce-2 were supplied by Haruta Gold Inc.
Preparation of gold samples
Au samples were prepared by deposition-precipitation method (59) or colloidal deposition method (69). For the deposition-precipitation method, in a typical procedure, the pH value of 40.0-ml HAuCl4 aqueous solution (1.25 mgAu/ml) was adjusted to ~9 with NaOH solution (0.1 M) under vigorous stirring. One gram of support was added to the above HAuCl4 aqueous solution, and pH was kept at ~9 by adding NaOH solution. After vigorous stirring for 1 hour, the product was heated to 65°C and stirred for another 1 hour. The precipitates were filtered, washed with deionized water for several times to eliminate Cl− ions, dried at 60°C overnight, and denoted as Au/S-fresh (where S represents the support; S = P25, anatase, rutile, and Fe3O4).
For the colloidal deposition method, in a typical procedure, 0.2 ml of 0.25 M HAuCl4 solution and 1.33 ml of 0.5 weight % PVA (Aldrich; Mw, 10,000; 80% hydrolyzed) solution (weight ratio of Au/PVA, 1.5:1) were added to 100 ml of water under vigorous stirring. After 10 min, 2.54 ml of the 0.1 M NaBH4 solution was rapidly injected into the solution to obtain a dark orange–brown solution, indicating the formation of gold colloid. One gram of P25 was then added immediately. After vigorous stirring for 6 hours, the solids were collected by filtration after washing and dried at 60°C overnight, followed by heating in 10 volume % O2/He flow at 300°C for 1 hour with the purpose of removing the PVA. The obtained sample was denoted as C-Au/P25-fresh.
Preparation of Ag/TiO2 and Cu/TiO2 samples
Silver and copper samples were prepared by a facile adsorption method: 0.5 g of TiO2 was added to 120 ml of fresh AgNO3 aqueous solution (0.42 mgAg/ml) or 100 ml of fresh Cu(NO3)2·5H2O aqueous solution (0.39 mgCu/ml) at 30°C and stirred overnight. Then, the precipitates were filtered and washed with deionized water for several times. The samples were dried at 60°C overnight, followed by calcination in air flow at 500°C for 1 hour, and denoted as Ag/TiO2-fresh or Cu/TiO2-fresh.
Pretreatment of the fresh samples
These fresh samples were further reduced under 10 volume % H2/He or 10 volume % CO/He flow for 1 hour at different temperatures and denoted as sample-HX or sample-COX. For comparison, some reduced samples were further oxidized under 10 volume % O2/He flow for 1 hour and denoted as sample-(HX+OY) (Y, the oxidation temperature) or sample-(COX+OY). For example, RR2Ti-(H500+O400) means the RR2Ti-fresh sample was first reduced in 10 volume % H2/He flow at 500°C for 1 hour and then oxidized in 10 volume % O2/He flow at 400°C for 1 hour.
HRTEM and HAADF-STEM analyses were performed with a JEOL JEM-2100F microscope operated at 200 kV. The EELS analysis was conducted on an FEI Tecnai G2 F20 microscope equipped with a Gatan Imaging Filter system operated at 200 kV. The chemical compositions of the covering layer of Au NPs were characterized by directly putting electron beam at the Au NPs in a STEM mode.
XRD patterns were collected at a PW3040/60 X'Pert PRO (PANalytical) diffractometer equipped with a Cu Kα radiation source (λ = 0.15432 nm), operating at 40 kV and 40 mA. A continuous mode was used to collect data in the 2θ range of 20° to 90°.
XPS was performed on a Kratos Axis HSi spectrometer with a monochromated Al Kα x-ray source operated at 90 W and a magnetic charge neutralizer. Samples were resistively heated in bespoke Ta crucible held within the analysis chamber. Reduction was performed under 1 × 10−7 torr H2 at 500°C for 5 hours, and reoxidation was performed under 1 × 10−7 torr O2 at 400°C for 5 hours, where the sample was cooled to room temperature and the analysis chamber was evacuated to 1 × 10−9 torr before spectral acquisition. Spectral processing was performed using CasaXPS version 2.3.16, where energy referencing to adventitious carbon at 284.6 eV as well as surface compositions and peak fitting were derived using appropriate instrumental response factors and common line shapes for each element.
EPR measurements were performed in a quasi in situ model using a bespoke U-shape reaction tube connected to a quartz EPR tube equipped with a greaseless high-vacuum stopcock. Samples were loaded into the U-shape reaction tube and exposed to various pretreatments. After pretreatment, samples were transferred to the EPR tube without air exposure. The EPR tube was subsequently connected to a vacuum system and evacuated at room temperature to pressures <10−4 torr. The EPR tube was then sealed and transferred for measurements at 100 K.
In situ DRIFTS spectra were acquired with a Bruker Equinox 70 spectrometer equipped with a mercury cadmium telluride detector and operated at a resolution of 4 cm−1. Twenty milligrams of the sample was loaded into the ZnSe window, which can work at a high temperature. Before CO adsorption, the sample was in situ pretreated in a flow (33.3 ml/min) of He at 120°C (for the fresh samples) or 10 volume % CO/He (for the CO atmosphere reduction sample of RR2Ti) or 10 volume % H2/He at different temperatures for 1 hour and then cooled to room temperature. The gas flow was switched to pure He to collect background spectrum. Subsequently, a mixture gas of 3 volume % CO/He (33.3 ml/min) was introduced into the reaction cell, and the spectra were collected with time until there was no change in it. For the reoxidation samples, an in situ heating progress under 10 volume % O2/He (33.3 ml/min) at a certain temperature for 1 hour was also performed before background spectrum was collected. For the reversibility spectra, before every cycle of CO adsorption, the sample was pretreated at 500°C under 10 volume % H2/He (for the first and third cycles) or at 400°C under 10 volume % O2/He atmosphere (for the second and fourth cycles) for 1 hour. After the sample was cooled to room temperature, the gas flow was switched to pure He and the background spectrum was collected.
Catalytic performance test
CO oxidation under model and simulated exhaust emission control conditions was conducted in a fixed-bed quartz reactor with a length of 200 mm and an inner diameter of 8 mm. To test the reversibility of CO oxidation under model conditions, 31 mg of RR2Ti-fresh diluted with 100 mg of SiO2 powder was first purged with He for 30 min and then pretreated at 500°C under 10 volume % H2/He (for the first and third cycles of CO conversion test) or 10 volume % O2/He atmosphere (for the second and fourth cycles of CO conversion test) for 1 hour. After cooling the sample to 80°C and purging with He for 30 min, a feed gas (1 volume % CO + 1 volume % O2 balanced with He) was passed over the catalyst bed with a flow rate of 33.3 ml/min, resulting in an SV of 64,452 ml gcat−1 hour−1. For the simulated exhaust conditions, CO oxidation was first performed under an atmosphere with water, the feed gas was 1.0 volume % CO + 1 volume % O2 + 10 volume % water balanced with He, using 10.8 mg of the catalyst diluted with 40 mg of SiO2. A full-simulated CO emission control test feed gas of 1.6 volume % CO + 1 volume % O2 + 0.01 volume % propene + 0.0051 volume % toluene + 10 volume % water balanced with He was subsequently used with a specified amount of the catalyst (diluted threefold in SiO2). The inlet and outlet gas compositions were analyzed by an on-line gas chromatograph (Hewlett Packard 6890) equipped with a TDX-01 column.
Supplementary material for this article is available at http://advances.sciencemag.org/cgi/content/full/3/10/e1700231/DC1
fig. S1. TEM images of various Au samples and the corresponding size distributions of Au NPs.
fig. S2. XRD patterns.
fig. S3. Ti 2p XP spectra of RR2Ti-fresh, RR2Ti-H500, and RR2Ti-(H500+O400) samples.
fig. S4. EELS spectra of RR2Ti-H500 sample.
fig. S5. Fitted EELS spectra as shown in Fig. 3G with a range of 450 to 475 eV.
fig. S6. HRTEM images of the RR2Ti-(H500+O400) sample.
fig. S7. HRTEM images.
fig. S8. In situ DRIFT spectra of CO adsorption.
fig. S9. In situ DRIFT spectra of CO adsorption on C-Au/P25-H500 and C-Au/P25-(H500+O400).
fig. S10. HRTEM images.
fig. S11. SMSI behavior of RR2Ti catalyst under CO treatment.
fig. S12. XRD patterns.
fig. S13. TEM images.
fig. S14. In situ DRIFT spectra of CO adsorption.
fig. S16. XRD patterns of Ag/TiO2 series samples with pretreatment under various conditions.
fig. S18. In situ DRIFT spectra of CO adsorption on Ag/TiO2-H500 and Ag/TiO2-(H500+O500).
fig. S19. In situ DRIFT spectra of CO adsorption on Cu/TiO2-fresh and Cu/TiO2-H500.
fig. S20. EPR spectra of the Ag/TiO2 series samples and Cu/TiO2 series samples obtained at 100 K.
fig. S21. Mass spectrometry signals of H2 for H2-TPR profiles of the samples of TiO2, RR2Ti-fresh, and Cu/TiO2-fresh.
fig. S22. In situ DRIFT spectra of CO adsorption on Cu/TiO2-H800, Cu/TiO2-(H800+O600), and Cu/TiO2-(H800+O600+H200).
fig. S23. HAADF-STEM images of RR2Ti-fresh before and after CO oxidation at 300°C for 100 hours and the corresponding Au size distributions.
fig. S24. CO conversion curves as a function of reaction time on the RR2Ti-fresh tested at 300°C.
fig. S25. CO conversion curves as a function of reaction time on RR2Ti-H500 and RR2Ti-(H500+O400) tested at 300°C.
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Acknowledgments: We thank Q. Fu at the Dalian Institute of Chemical Physics (DICP) for his useful discussion. We also thank H. Han at the DICP for his help in analyzing the EPR measurements. Funding: This work was supported by National Key R&D Program of China (2016YFA0202801 and 2016YFA0202804), the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB17020100), the National Natural Science Foundation of China (21776270, 21476232, and 21303184), and the Department of Science and Technology of Liaoning Province (2015020086-101). B.Z. acknowledges the financial support provided by the National Natural Science Foundation of China (91545119), the Youth Innovation Promotion Association of the Chinese Academy of Sciences (CAS) (2015152), and the Strategic Priority Research Program of the CAS (XDA09030103). Author contributions: H.T. performed the catalyst preparation, characterizations, and catalytic tests. Y.S. conducted the HRTEM examination. B.Z. and D.S. conducted the EELS examination and analysis. A.F.L., M.A.I., and K.W. conducted the XPS examination and analysis. L.L. conducted the in situ DRIFTS characterization. Y.R., J.H., M.H., X.L., and C.J. helped with the catalyst characterizations and the data analysis. B.Q., J.W., and T.Z. conceived the idea, designed the study, analyzed the data, and cowrote the paper (assisted by A.F.L.). All the authors discussed the results and commented on the manuscript. Competing interests: The authors declare that they have no competing interests. Data and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. Additional data related to this paper may be requested from the authors at wangjh{at}dicp.ac.cn.
You are going to email the following Classical strong metal–support interactions between gold nanoparticles and titanium dioxide
By Hailian Tang, Yang Su, Bingsen Zhang, Adam F. Lee, Mark A. Isaacs, Karen Wilson, Lin Li, Yuegong Ren, Jiahui Huang, Masatake Haruta, Botao Qiao, Xin Liu, Changzi Jin, Dangsheng Su, Junhu Wang, Tao Zhang
Science Advances 13 Oct 2017 : e1700231
The classical strong metal–support interaction between TiO2 and IB metals was demonstrated.


text:
Home Top News Ulema condemn use of force against state in name of 'Nifaz-e-Shariah
Ulema condemn use of force against state in name of 'Nifaz-e-Shariah
Ahsan urges ulema to use digital platform against forces of hatred, terrorism
Zubair Qureshi
Federal Minister for Planning, Development & Special Initiative Ahsan Iqbal has called for establishing a social media cell to spread Islam's message of tolerance and brotherhood at a wider level and in different languages.
While addressing the closing session of the Paigham-e-Pakistan national conference titled "Countering Violent Extremism, Radicalism and Hate Speech" as chief guest here on Monday, Ahsan Iqbal said intellectuals, ulema and religious scholars could play an important role in spreading this massage at the grass-root level by using the digital platform.
The national conference was jointly presided over by Prof Dr Nabi Bux Jumani, Acting President of the International Islamic University, Islamabad (IIUI) and Dr Muhammad Ziaul Haq, DG Islamic Research Institute, IIUI.
Ahsan Iqbal said we are living in an age of digital media and ulema and scholars should make maximum use of this important forum and have their own FM Radio channel to raise their voice most effectively against militancy and extremism.
Earlier the ulema and mashaikh who were attending the forum and had come from all over the country to participate in the conference, unanimously condemned the use of force against the state in the name of 'Nifaz-e-Shariah.' Taking up arms against the state in the name of Islam or Shariah is against the basic spirit of Islam and the teachings of Islam, they said.
Such elements are in fact playing in the hands of the enemies of Islam and Pakistan.
"This forum of religious scholars reiterates that all such elements that are waging a war against the state by indulging in linguistic, territorial, religious or ethnic confrontations are in fact violating the principles of Islam and Shariah and the state should deal with such elements with an iron hand," said a communiqué issued at the end of the closing session.
The joint statement held that Paigham-e-Pakistan that was issued on January 16, 2018 from the Aiwan-e-Sadr truly reflected the collective wisdom of the nation with regard to Quran, Sunnah and should be implemented in the country as policy and both the house of the Parliament should also pass this.
The ulemas urged the security institutions of the country to continue operations against the enemies of the state and Islam and take all steps necessary to eradicate terrorism from Pakistan.
About the recent incident of desecration of Quran in Sweden, the participants condemned the incident in strong words and said it had hurt over 1.5 billion Muslims all over the world. The participants also expressed concerns over the illegitimate use of social media and called for an end to its use to preach hatred in the name of nationalism, religion or any other excuse.
The communiqué issued at the end of the Paigham-e-Pakistan National Conference was signed by eminent scholars of Islam including Chairman Islamic Ideological Council (IIC) Dr Qibla Ayaz, President Wafaq-ul-Madaris Mufti Muhammad Taqi Usmani, Chairman Pakistan Ulema Council Hafiz Tahir Ashrafi, Chairman Ruet-e-Hilal Committee Maulana Abdul Khabeer Azad, President Tanzeem-ul-Madaris Mufti Muneeb-ur-Rehman, Prof Sajid Mir, Qari Muhammad Hanif Jalandhri, Mauulan Azizul Hassan, Maulana Hamid Haqani, Allama Hamid Saeed Kazmi, Fazlur Rehman Khalil and others.
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meaningless drivel
Dennis Barrow
Location: 10 miles NW of Helena Montana
AC/DC has apologized,
but due to inflation,
dirty deeds are no longer dirt cheap.
Real funny, Scotty, now beam down my clothes!
The only thing...more expensive than education is ignorance.~Ben Franklin Better Wood Heat: DIY Rocket Mass Heaters 4-DVD Set as tiny download: https://permies.com/jforum?module=paidTopic&action=buyWithPaypal&topic_id=63926&f=232
Location: Pacific Wet Coast
Why do Hamburgers go to the gym?
To get better buns.
Visit Redhawk's soil series: https://permies.com/wiki/redhawk-soil
How permies.com works: https://permies.com/wiki/34193/permies-works-links-threads
How did the skeleton survive the accident?
He made a marrow escape.
A man name Rudolf is a communist; some people just call him "The Red." He's sitting at breakfast with his wife one day and looking out the window says, "It looks like it's raining out there."
His wife responds, "No, it's pretty cold out today. I think that's snow."
The man looks sternly at his wife and says, "Don't contradict me. Rudolf the Red knows rain, dear."
sorry, I couldn't resist...
Location: Northern WI (zone 4)
"Inflation's really getting out of control"
Sorry that's just my 4 cents
SKIP books, get 'em while they're hot!!! Skills to Inherit Property
Discount early bird ticket to the 2023 Permaculture Technology Jamboree
What's red and smells like blue paint?
Red paint
Location: Maine, zone 5
So the painters finish painting my home and they hand me the bill.
I notice that by the paint it says $0.
I say, "You guys did such a good job, why aren't you charging me for the paint?"
The head painter looks at me and says, "Don't worry about the paint, it's on the house."
Permaculture...picking the lock back to Eden since 1978.
Pics of my Forest Garden
One day a man hears that a distant uncle passed away.
He's a little sad, but only a little, for they barely knew each other.
Then, a few days later, a package arrives.
It contains his inheritance from the estate: A violin and a painting.
He has no idea what to do with them.
After pondering the matter, he takes them to an appraiser.
Not too long later the appraiser calls him: "I've finished my analysis, and I've got some good news. There's no doubt at all that what you have is a genuine Van Gogh and a genuine Stradivarius."
The man is ecstatic: "I can sell these for millions!"
The appraiser says "Well, you can sell them, and they'll fetch some money for their novelty value. But not millions. You see, the truth is, Stradivarius wasn't much of a painter… and Van Gogh made lousy violins."
Location: Northeast Oklahoma, Formerly Zone 6b, Now Officially Zone 7
A fellow who sees a sign outside a house that reads: "Talking Dog for Sale."
The fellow walks up to a dog sitting on the front porch, and the dog says, "May I help you mister?"
"You really can talk!" says the man. "You're amazing!"
"My life has been amazing," says the dog. "My talking skills helped me communicate with human authorities and other dogs to save avalanche victims in the Alps, as well as earthquake and hurricane victims all over the world. Now semi-retired, I spend my days telling jokes at the local children's hospital."
The fellow, flabbergasted, asks the dog's owner, "Why on Earth would you want to sell an incredible dog like this?"
"Because he's a compulsive liar!" said the dog's owner. "He's never left the yard!"
"You meet your destiny on the road you take to avoid it."
As I get older, I remember all the people I've lost along the way and I think to myself....
maybe a career as a tour guide wasn't for me.
A guy walks into a crowded bar, waving his unholstered pistol and yelled: "I have a 45 caliber Colt 1911 with a 7 round magazine plus one in the chamber and I want to know who's been sleeping with my wife!"
A voice from the back of the room calls out: "You're gonna need more ammo!!"
K Eilander
Location: Rocky Mountains, USA
Dennis Barrow wrote: AC/DC has apologized,
That's too bad. Guess I'll have to muck out the chicken coop myself. ;)
If you don't "know enough"... try anyway! (Cuz that's how you learn.)
My friend can't afford to pay his water bill anymore, so I sent him a card, "Get well soon."
(I apologize in advance for this one)
I told Siri that my dog just died and asked her if she would tell me a joke to cheer me up. She said "yes" and then "Knock, knock".
"Who's there" I replied.
"Not your dog" said Siri.
What do you call a snowman with a six pack?
An abdominal snowman.
Sure you're just sledding now
– But sledding is a gateway to other things.
Soon you'll be tobogganing.
And snow-tubing.
And snowboarding.
And skiing.
It's a slippery slope.
Why didn't Guns N Roses turn up for the gig when it was snowing?
Axel Froze.
A wise person once said.
1. We all love to spend money buying new clothes but we never realize
that the best moments in life are enjoyed without clothes.
2. Having a cold drink on hot day with a few friends is nice, but
having a hot friend on a cold night after a few drinks - PRICELESS.
3. Breaking News: Condoms don't guarantee safe sex anymore. A friend
of mine was wearing one when he was shot dead by the woman's husband.
4. Arguing over a girl's bust size is like choosing between Molson,
Heineken, Carlsberg, & Budweiser. Men may state their preferences,
but will grab whatever is available.
5. I haven't verified this on Snopes, but it sounds legit… A recent
study found that women who carry a little extra weight live longer
than the men who mention it.
I am right 98% of the time.
Who cares about the other 3%.
Location: southern Illinois, USA
You know, it seems like my wife and I have been together forever; but sometimes she is really irritating. The weather has been pretty raw around here, so I made a point of having a roaring fire going when she got home. Immediately, the complaining began …. Something about us not having a fireplace.
We live on Blue Planet that circles a ball of fire. Our Planet is circled by a Golden Moon that moves its oceans. Now tell me that you don't believe in miracles....Unknown
Jay Angler wrote:
"The base is under a salt!" The chemist replied.
Did you know why all the Chemists were voting for Ron Paul years back?
Because, they are always saying, Elect-Ron! Electron!
I had to give up my first career early due to fallen arches. Anyway, once I quit the architecture firm I went into business.
R Sumner
Everyone knows that six is afraid of seven because seven eight nine.
Turns out seven was just that hungry, despite an earlier offer of pi.
(Which he refused even though he knew it was irrational).
What is Santa's nationality?
North Polish.
Dark humor is like clean water.
Not everyone gets it.
After a basketball game, the coach found a cell phone on the gym floor. He picked it up and handed it to one of the referees, saying, "Here's your phone."
"What makes you think it's mine?" the ref asked.
"Easy," the coach replied. "It says you missed 13 calls."
Team work is important; it helps to put the blame on someone else.
Matt McSpadden
Location: Central Maine (Zone 5a/4b)
Engagement Ring - a tourniquet applied to the left ring finger to stop circulation.
"The future is something which everyone reaches at the rate of sixty minutes an hour, whatever he does, whoever he is." C.S. Lewis
"When the whole world is running towards a cliff, he who is running in the opposite direction appears to have lost his mind." C.S. Lewis
I was incredibly surprised when the stationary store moved
"It's ok to use bad English... as long as you know that you are using it" - Walter Yoho
Dennis Barrow wrote: Team work is important; it helps to put the blame on someone else.
Reminds me of the old demotivational poster, "Teamwork: Because none of us is as dumb as all of us."
Never make snow angels at a dog park.
305967289_10223524812803306_8766470681300994284_n.jpg
Friends are like snow
– When you pee on them, they disappear.
What separates snowmen from snow-women?
– Snow Balls
Here is a tip that might save your life. A shark will only attack if you are wet.
This tiny ad will self destruct in five seconds.
Switching from electric heat to a rocket mass heater reduces your carbon footprint as much as parking 7 cars
http://woodheat.net
Jokes, part deux
Got my playing cards.. what games should I learn?
Laugh your ass off funny group games
ecology games?
Any creative card games for the Permaculture Playing cards?
no make-up / natural beauty
Mountain girl that loves to learn
What are some things you find attractive/cute/sexy/etc. that others likely don't?
Dear Paul


text:
JOCELYNE YOUNG (SEGUIN)
Born: Apr 14, 1949
Date of Passing: Dec 09, 2021
JOCELYNE YOUNG
(nee SEGUIN)
April 14, 1949 – December 9, 2021
It is with sadness that we announce the passing of Jocelyne Young at the age of 72 years, on December 9, 2021.
Predeceased by parents, Roland and Jean Blanche Seguin. Left to cherish her memory is her husband of 42 years, Colin Young; sisters, Leanne and Lyse; as well as many nieces, nephews, cousins and friends.
Jocelyne was born in Montreal, Quebec and graduated from College Mother House. Her first job was secretary to the head of the World Bank in Washington, DC. She spent a year there, until she returned to Montreal where she joined the accounting firm of Coopers & Lybrand, where she worked for three years. Jocelyne later became a training manager with RJR-MacDonald Inc., moving to Toronto, ON; it was at this job that she met her future husband, Colin Young, at a company golf tournament. They were married in 1979 and they were inseparable for 42 years.
Jocelyne and Colin resided in Toronto up until their retirement in 1997, where they later moved to Lake Joseph in Muskoka, ON spending their winters away in Rancho Mirage, California. In 2008, they moved to Winnipeg, residing in Old Tuxedo while still enjoying their winters away in California.
As per Jocelyne's wishes, cremation has taken place and no formal service will be held.
If friends so desire, donations may be made to the Heart & Stroke Foundation of Manitoba, 1379 Kenaston Blvd., Winnipeg, MB R3P 2T5.
THOMSON FUNERAL HOME
Condolences may be sent to
www.thomsonfuneralchapel.com
As published in Winnipeg Free Press on Dec 18, 2021
Her mother's name was Jeanne-Mance Lepage Séguin and Liane was her sister's. Repose en paix Jocelyne, Ta soeur Lyse - Posted by: Lyse Séguin (sister) on: Dec 22, 2021
669 Broadway Ave. (Map)


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text:
The Ride Guide
Do you have an idea for a ride, but you're not sure how to make it happen? Do you want to lead a ride, but you still need an idea?
This guide can help you out
Have a ride idea?
Add it to the calendar!
Events this week Monthly calendar Add an Event!
Mending Ride With Makemobile
Gamelan Bike Bike at the Vancouver Jazz Festival
Agustin Beltran - Memorial Ride
Youth Bike Club Ride
Come Meet Spokesmama
Pink Floyd: The Sea Wall
Sunny Sunday 'Coffee in the Heights' Ride
Park Ride with the Sea Lions
Vintage Bicycle Ride - Vancouver Wheelmen
Gender Liberation Night at the Bike Kitchen
Seventy Years of Vancouverism: Exploring urban density from the West End to Senakw
A Few Interurban Stations Along the Greenway
Ride along with the Bibliobike: Bike Maintenance 101
Donuts at Black Tiger Coffee
Our Community Bikes AGM
Pride Night at the Bike Kitchen
Friday, July 1, 2022 at 6:00pm. Meet at 6, ride at 6:30
Science World - where the Gazebo once was.....
1455 Quebec St, Vancouver, BC V6A 3Z7
Notes: meet at the circle where the Gazebo once was.....
www.facebook.com/events/42807...
http://makemobile.ca
By: Amy Biker WalkerWe'll enjoy a leisurely ride, visit 2 or 3 sweet sitting spots where we can pull out our handwork (mending, darning, knitting, crochet, needle felting etc.) and have a make-out / hang-out. This is an era of care and repair – let's make it a social occasion and reinforce our relationships as well as our pants! Bring items that need mending / patching / darning! I'll supply fabric for patching and hand-sewing supplies for people who do not have a project already on the go. We can offer each other advice and instruction – please bring your own items that [more...]Read comments and more
Saturday, July 2, 2022 at 1:30pm
Roundhouse – Performance Centre
181 Roundhouse Mews Vancouver, BC V6Z 2W3
www.facebook.com/gamelanbikeb...
https://www.coastaljazz.ca/event/gamelan-bike-bike
By: Gamelan Bike BikeGamelan Bike Bike gets its musical inspiration from Indonesia and its raw materials from Vancouver's scrap heaps. Founded in 2012, the community-based ensemble has transformed discarded metal—including over 100 bicycle frames—into tuned metallophones and gongs to perform new music for gamelan, including recent works from Balinese composer I Putu Gede Sukaryana (Balot). $10 at Door only OR part of the Roundhouse Performance Centre Pass; only $34 for all six shows! Also, during June 25th – 26th and July 2nd – 3rd, The Bicycle Valet will be at the #VanJazzFest to park your bikes for you – for free! See https://t.co/LC2rW0RefV/.Read comments and more
Sunday, July 3, 2022 at 11:00am
750 Hornby Street, Vancouver, BC
www.facebook.com/wearehub/pos...
By: Ron RichingsAgustin, a 28 year old PhD student at UBC, was fatally injured Wednesday while riding in a separated bike lane on Pacific Ave. He was struck by a large truck while crossing Hornby in the marked bike crossing. The infrastructure at this location is among the best in the City, in terms of protection for people walking and cycling. On Wednesday, it wasn't enough. There will be a memorial ride for Agustin on Sunday July 3, meeting at the Art Gallery at 11 am. Please consider coming out to show your support for Agustin's family, who have flown in this [more...]Read comments and more
Tuesday July 5
Tuesday, July 5, 2022, 4:00pm - 5:30pm. Meet at 4pm and roll out at 4:40pm.
Repeats: First Tuesday of every month
Our Community Bikes
2429 Main Street, Vancouver, BC
Notes: Near East Broadway and Main Street.
www.facebook.com/OurCommunity...
https://ourcommunitybikes.org
By: OCBOur Community Bikes?' Bike Club has starting up rides again!! The first Tuesday of every month, youth are welcome to join us for group rides. We'll meet up at at 4pm, tune up our bikes if needed, roll out at 4:30ish, and plan to be back at the shop around 5:30/5:45pm. These rides are NO DROP and ALL BIKES WELCOME rides. Meaning no one gets left behind and all biking levels are welcome! Don't forget your helmet and water. Hope to see you there!!Read comments and more
Wednesday July 6
Wednesday, July 6, 2022 at 5:30pm. Games usually start at 6pm wrap up at dusk, depending on number and keenness of attendees.
Repeats: Every Wednesday
1657 Charles Street, Vancouver, BC
Message us at https://www.facebook.com/groups/evbpnewbiebikepolo
By: East Van Bike PoloEast Van Bike Polo presents Soft Serve Wednesday. Please invite all the new & aspiring players ! This is your chance to take your first steps & get your POLO started. Court time for new players is prioritized, although regulars will be on hand to provide loaner gear and nerd out about polo. You can play a few non-competitive games of pick-up, or just to say hi and check things out. Bring your friends, too! You can use your own bike, or borrow one at the loaner bikes. Loaner mallets will be provided as well.Read comments and more
Wednesday, July 6, 2022, 7:30pm - 8:00pm
By: OCBCome and hear Lisa, aka Spokesmama at Our Community Bikes' WTQ Night, and learn about her experience, tips, and tactics for cycling with little ones, followed by a Q&A. This workshop is from 7:30 to 8pm. There is limited capacity, and an RSVP is required. Masks are no longer mandatory, but encouraged at this event and will be worn by program staff. WTQ Night is Our Community Bikes' twice a month night where we open our doors after hours to women, trans, and queer identifying people to use the shop and have specific opportunity to further their mechanic skills. Though [more...]Read comments and more
Wednesday, July 6, 2022 at 8:00pm
Repeats: First Wednesday of every month
Pat's Pub
403 E Hastings St, Vancouver
terminalcityriders.ca/events/first...
By: Night OwlsCome join the Night Owls for the First Wednesday of the Month ride! Meet up at Pat's Pub, you can bring your bike inside – park on the East side (by the Pinball and Skee Ball machines). Grab a beer, or a meal and support this local establishment in East Van, then we're off! Ride departs just after 8:00. Easy cruise to the 9 O'clock Gun and Salmon back over to Oasis (between 2nd and 3rd beach), Third Beach by trails, or Beaver Lake until the Seawall is fixed up. All bikes and riders welcome!Read comments and more
Thursday July 7
Thursday, July 7, 2022 at 8:00pm. Meet at 8, ride sometime after 8:30.
By: Bike Rides SocietyThis weekly ride will take you places you've never been before in a casual, follow the leader kind of way. All levels welcome, all encouraged; we go as fast as our slowest rider and no one gets left behind! We ride rain or shine, all year round, every Thursday. Anywhere from 6 to 30 riders, BRS is a weekly adventure built for good convo, steady peddling and roads less travelled and/or well loved. Going into it's 7th year, BRS boldly bikes on full of enthusiastic smiles, plenty of laughs and good times. BYO whatever spells a fantastic bike ride for [more...]Read comments and more
Friday, July 8, 2022 at 8:30pm. Ride leaves 9 pm sharp
Creekside Park
1455 Quebec St, Vancouver, BC
Notes: North side of Science World
fb.me/e/21D90VOjs
By: MikeOn November 30th 1979 Pink Floyd released an album called "The Wall". 43 years later, on July 8th, 2022 a group of elevated individuals will ride the Sea Wall during the entirety of the album, a glorious 1 hour and 21 minutes. We will ride under the moon this night but all sorts of trippy lights are appreciated to keep everyone comfortably numb. Is there anybody out there who wants to come? I will bring the boys back home or we will all be waiting for the worms. The Route: The year we are going to meet at Creekside park, [more...]Read comments and more
Sunday July 10
Sunday, July 10, 2022, 8:45am - 11:30am
Cap's New West (Original) Bike Shop
434A East Columbia Street, New Westminster, BC
By: Cap's Bike ClubJoin Julia and Cap's Bike Club or a relaxed ride exploring Burnaby bike paths. Some gravelly bits. We'll do some easy climbing, have coffee on Hastings St., and cruise back. Check out the route here ! https://www.strava.com/routes/2979446979093105078 RSVP clubcapsbicycleshop.comRead comments and more
Sunday, July 10, 2022 at 9:00am
Cap's Port Moody Bicyle Shop
2840 St Johns St Port Moody, BC
www.facebook.com/pages/Caps-B...
By: Cap's Bike ClubJoin Cap's Bike Club for an E-Bike ride leaving from Cap's Port Moody Shop, and heading to Barnet Marine, and New Brighton Park, with a stop to see the sea lions on the way. Approx 45 -50km Please RSVP to clubcapsbicycleshop.comRead comments and more
Sunday, July 10, 2022 at 12:00pm. Meet at 12ish, ride at 1:00pm
Bird Square - Olympic Village
Manitoba st & False Creek
By: Ron RichingsIt's been a long time! Let's get back at it with a Vintage Ride! Time to dust off your rusty gold or polish up your best ride for a slow roll this Sunday. Meet up at Angry Birds at High Noon and roll at 1pm sharp. Look forward to seeing everyone and their bikes again!!!Read comments and more
Wednesday July 13
Wednesday, July 13, 2022 at 5:30pm. Games usually start at 6pm wrap up at dusk, depending on number and keenness of attendees.
Wednesday, July 13, 2022, 6:15pm - 9:00pm
Repeats: Second Wednesday of every month
The Bike Kitchen
6138 Student Union Boulevard, Vancouver, BC
Notes: New Location: Room 36, UBC Life Building
calendar.google.com/calendar/u/0...
http://www.thebikekitchen.com
By: Bike KitchenGender Liberation Night is a monthly Access Night for cis-women and trans and/or non-binary people of all genders to use the UBC Bike Kitchen's shop space and tools, supported by informal mentoring. The purpose of the night is to offer a more welcoming, safer atmosphere in which people who are typically marginalized within the cycling community because of their gender identity and/or expression can work on their bikes, learn mechanics, and form connections. A staff mechanic and volunteer aligned with the night's target demographic will be available to empower participants in performing their own repairs. Gender Liberation Night will take [more...]Read comments and more
Saturday July 16
Saturday, July 16, 2022, 10:00am - 1:00pm. Depends how many times we stop along the way!
English Bay
Denman at Davie.
Notes: Next to the 'A - mazing - Laughter sculpture
By: Gordon PriceJoin past-city councillor Gordon Price on a circumnavigation of False Creek, from the West End to the site of the Senakw project at Burrard Bridge. Along the way, you'll see examples of Vancouver's experiments in livable urban density, from the 1950s West End to 1990s North Shore False Creek to the 1970s South Shore – with proposals for 2020s megaprojects. Of course, what connects them all is the Seaside Bikeway, one of our most important achievements in creating a great city.Read comments and more
Tuesday July 19
Tuesday, July 19, 2022 at 6:00pm. Meet at 6:00, leaving at 6:15...
Strathcona Station
East Boulevard and 37th Avenue
Notes: The south east corner at the school
http://johnatkin.com
By: John AtkinThe Arbutus Greenway is the former BC Electric Railway's Interurban line to Steveston and on this ride we'll explore the area around some of these stations and look at how they developed and changed over time. All aboard for Strathcona (yup, it's a westside name too), Royal and Granville Road. An easy ride along the Greenway and neighbourhood streets.Read comments and more
VPL Britannia Branch
1661 Napier St. Vancouver
vpl.bibliocommons.com/events/62a75...
By: Vancouver Public LibraryCome check out the Vancouver Public Library's new ride: the BiblioBike! Meet at the VPL's Britannia Branch and walk, ride, or roll down to Woodland Park, where we'll explore Bike Maintenance 101. Bring your bike and questions – or simply join us for a park hang out with book speed dating! For ages 13-18. To register please email teensvpl.caRead comments and more
Sunday, July 24, 2022, 8:45am - 12:45pm
The Original Cap's Bike Shop
By: Cap's Bike ClubJoin Nicole and Andrew of Cap's Bike Club as we ride into Langley to look for more donuts at Black Tiger Coffee. https://www.strava.com/routes/2984638226210181712 RSVP on Facebook or by email at clubcapsbicycleshop.comRead comments and more
Monday, July 25, 2022, 5:30pm - 7:00pm
A vertual meeting
mailchi.mp/15a6c6b15b19...
By: Our Community BikesIt's our Annual General Meeting and we'd love it if you'd show up to support us and vote on our incoming directors, hear some updates, and give virtual high fives. Afterwards we will meet up in Jonathan Rogers Park to hang out and have snacks – just look for the Our Community Bikes tent. 5:30pm – 7pm Monday, July 25 2022, on Google Meets. 7:30pm – Meet up in Jonathan Rogers Park Email Sophia to RSVP and receive the meeting link! ssudermanourcommunitybikes.org. Pedal Society and Pedal Foundation AGM Agenda 1. Call to Order 2. Coast Salish Acknowledgement 3. [more...]Read comments and more
Repeats: Fourth Wednesday of every month
By: Bike KitchenPride Night is a monthly Access Night that provides a positive space for anyone in LGBTQ2S+ community to use our UBC Bike Kitchen shop resources for free in a relaxed environment facilitated by queer mechanics and volunteers. Bring your own bike, come with questions and ask away, play games or just come hang out with other community members. Beginners are always welcome! Gender and sexuality will not be policed at this event. We ask those who do not identify as part of the LGBTQ2I+ community to come by for DIY repairs any time during our normal open hours. A staff [more...]Read comments and more
Notes: Near West Broadway and Main Street
www.facebook.com/watch
https://www.facebook.com/OurCommunityBikes
By: OCBThat's right – Every 4th Wednesday night night we're running the DIY stands. Roll on up between 7:30 and 9:30 pm. And if you miss it tonight, DIY is also open eve Saturday eve 7:30-9:30pm. See you thereRead comments and more
Friday, July 29, 2022 at 6:00pm. Meet at 6:00pm and ride at 6:30pm
Repeats: Last Friday of every month
Notes: Georgia Street side
https://www.facebook.com/groups/criticalmassvancouver
By: Vancouver Critical MassCome celebrate cycling, ride in a parade, joining other cyclists around the globe!Read comments and more


text:
Melania Trump says 'violence is never the answer' in White House farewell speech | Trump News
America's demise is near at hand – R.I.P — Society's Child –
Closed California versus open Florida, who is outperforming the other?
US-based nonprofit sues Apple to REMOVE Telegram over failure to censor 'hate speech,' cites Parler crackdown as example
Mika Brzezinski, Joe Scarborough Slam Tech Giants for Not Censoring More
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Trump & Politics
MiLB season canceled amid COVID-19 pandemic
July 1, 2020 Source Listed	0 Comments
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FILE PHOTO: A basket of baseballs for batting practice are seen at the old 1931 Municipal Stadium before the start of a Minor League game between the hometown Hagerstown Suns and the Kannapolis Intimidators, in Hagerstown, Maryland, August 9, 2014. REUTERS/Mike Theiler
Around three months after Minor League Baseball was due to open play, the 2020 season was canceled Tuesday due to the coronavirus pandemic.
The move came after Major League Baseball (MLB) informed Minor League Baseball (MiLB) that it would not be supplying players for affiliated teams this year.
"These are unprecedented times for our country and our organization as this is the first time in history that we've had a summer without Minor League Baseball played," MiLB president and CEO Pat O'Conner said in a statement posted on Twitter. "While this is a sad day for many, this announcement removes the uncertainty surrounding the 2020 season and allows our teams to begin planning for an exciting 2021 season of affordable family entertainment."
The move wipes out play for 160 teams, from Triple-A at the top tier to the Rookie level at the bottom, scrapping a central event of summer life in small towns and big cities.
MLB had already cut down its season from 162 to 60 games, with play scheduled to start on July 30. The losses MLB teams incurred from the wiped-out portion of the schedule, and the prospect of playing much or all of the shortened slate without fans in the stands, led to the economic climate that left clubs unwilling to foot the bill for minor-leaguers' salaries.
Many MiLB teams had laid off or furloughed employees while waiting for a final determination on the season that would have run through approximately Labor Day.
It is unclear how deeply the Tuesday announcement will affect the minors moving forward.
Baseball America reported in April that MiLB agreed to an MLB proposal first proffered last year: a reduction of the number of affiliated from 160 to 120. However, MiLB issued a statement denying the report.
Minor league players under contract to MLB teams were paid $400 weekly stipends during the shutdown through Tuesday.
According to Baseball America, the Atlanta Braves, Chicago Cubs, Cleveland Indians, Pittsburgh Pirates, Texas Rangers, Tampa Bay Rays, Colorado Rockies, Chicago White Sox and New York Yankees had agreed to extend those payments through July 31.
The Houston Astros, Milwaukee Brewers, St. Louis Cardinals, Los Angeles Dodgers, Seattle Mariners, Miami Marlins, New York Mets, San Diego Padres, Boston Red Sox, Kansas City Royals and Minnesota Twins reportedly agreed to continue stipends through Aug. 31. The Philadelphia Phillies stated that they will pay minor-leaguers the stipend through Sept. 5, and the Oakland Athletics, Toronto Blue Jays, San Francisco Giants, Washington Nationals, Baltimore Orioles and Cincinnati Reds said they would keep paying through Sept. 7.
The timeframe for the Detroit Tigers was uncertain, per Baseball America.
(Field Level Media)
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Arizona vintage shop praised for 'spot-on' sign mandating masks: 'Love your sense of humor'
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This page compiles resources about political campaign contributions.
Case study: Vision Vancouver's 2014 donations over $1,000. Are contribution limits the key to limiting big money in civic politics?
Specific data for the 2011 civic election, for Vision Vancouver, the winning party, is here for download in PDF and Excel formats. Note that creating a file like the Excel file below consumes a considerable amount of volunteer work and technical skill. CityHallWatch is not aware of any other entity that attempted this analysis for the 2011 election.
Apparently, Gregor Robertson did not receive any direct contributions to his own mayoral campaign as a candidate.
Another important note: The donation declarations are done on an "honour system." NO INDEPENDENT AUDIT is conducted. Of particular concern is reporting of "in-kind" donations. The lack of a solid system for tracking gifts, cash, and in-kind donations leaves Vancouver's civic system open to the potential for corruption. See our Six Actions to Clean Up Vancouver Politics, and join the movement!
Candidates and elector organizations are not required by law to report their campaign contributions until 120 days after the election.
Neighbourhoods for a Sustainable Vancouver ($38,000, PDF media release) and the Vancouver Greens (about $15,000) disclosed their interim figures on November 17, in response to a challenge by Occupy Vancouver.
Media reports suggest that in 2011, Vision Vancouver and the Non-Partisan Association may have doubled their expenditures from 2008 ($2.5 million and $2.1 million, respectively, in 2008). In media, COPE has reported expenditures of about $340,000.
CityHallWatch has annotated a list of donors that attended a Vision Vancouver Fundraiser in November 2011 (source: Vancouver Sun).
Vancouver Courier reporter Mike Howell's blog on "A night at the NPA Fundraiser" (4-Nov-2011) indicates some attendees, but no complete list.
Link to Vancouver Sun database on 2008 civic election contributions and related articles (excellent reading) about campaign finance reform. Use this database to search by municipality, by elected official, and by donor.
Citizen analysis of contributions for 2008 election from developers.
(CityHallWatch Table 2 Developer $ Vancouver Election 2008-10 (ranked for total)).
These tables include the VISIONVANCOUVER.supplementaryreport which adds details disclosed by Vision in July 2010 about funds collected to pay off the $240,000 debt owed by Vision Vancouver to an unreported source at the end of the 2008 election.
Further below is a note about the difficult methodology of compiling.
In particular, links to campaign financing disclosures from 2008. Note that these are in scanned PDF format, making it impossible to search electronically. See box in top right for links.
Note that organizing this data is very time consuming. The City does not make it easy for citizens to access and manipulate this data. The City of Vancouver website in 2008 provides only scanned PDFs of the data submitted by candidates and elector organizations.
A researcher who prepared Table 1 and 2 above provided CityHallWatch this explanation: I was interested in the amounts pledged by developers and so had to go into the material the hard way. I had to the raw data (links by the Sun) and then take a screen shot (jpg) of each set of 15 donations. Since there were 6044 donations that means going through 402 pages, taking a screen shot of each one and then inputting that data into a spread sheet. Each screen shot also involves a Google search on any likely 'real estate' contributor. It would be even more complicated to break down donations by major category (e.g., unions, green business interests etc). The bottom line is that a full analysis of donations would probably require 2 person-weeks or more. If I were to be uncharitable, I would say that the reason the reported data on donations is presented in the form that it is is to meet the letter of law on reporting but to make it nigh impossible to see what is really happening. I limited myself to 40 pages (600 donations) or about 10% of the total ranging from the largest to smaller amounts and I have attached the first 20 pages (as jpgs). Bob Rennie and Renewal figure prominently on the first page. I suppose it would be possible to convert all the jps to pdfs, OCR them and then search by name. The real estate/developer community is even more difficult to get at because of the practice of creating separate business entities (I would like to say 'front') either for accounting purposes or to ensure anonymity – hence the reliance on Google.
Official info on contribution disclosure: Campaign financing disclosure statements (http://vancouver.ca/ctyclerk/election2008/candidate-profiles.htm) Every candidate's financial agent must file a campaign financing disclosure statement no more than 120 days after the election (March 16, 2009). If anything changes after the statement is filed, the financial agent must file a supplementary report within 30 days of becoming aware of the change. Failure to file a complete campaign financing disclosure statement or supplementary report may lead to penalties, up to and including disqualification from holding office until after the next general local election. A campaign financing disclosure statement must be filed even if no campaign contributions were received, and no election expenses were incurred. Campaign financing disclosure statements will be available for public inspection for seven years after the election.
ThinkCity (http://www.thinkcity.ca/node/150) about 2008 election costs.


X3M Music act, Simi wants you to know that her debut album titled Simisola will be released a month from today, on the 8th of September, 2017.
Over the last few years the singer has worked really hard emerging as the Best Female Vocal Performance for 'Love don't care' at the Headies 2016.
Although Simi has not revealed the track-list but the album Simisola is something we look forward to.