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UPDATED: Railroad 'Quiet Zone' work starts Monday in Mason City
Two streets will be permanently closed.
Posted: Mar 18, 2018 2:09 PM
Updated: Mar 19, 2018 7:29 PM
MASON CITY, Iowa – Work on the Quiet Zone along the Union Pacific Railroad line through Mason City began Monday morning.
Due to a last minute change, City Engineer Mark Rahm says that instead of 4th Street SW being closed first at the rail line directly west of Monroe Avenue, the 9th Street NW crossing closed first. The closing of 4th Street SW will instead happen two or three days later. Equipment called Supplemental Safety Measures, such a lane delineators, offset directional sidewalk crossings and additional signage, will also been installed at the rail crossings for 15th Street SW, 6th Street SW and 1st Street NW.
Greg Shirk, the owner of Acute Care Chiropractic, which is located next to the UP line on 1st Street NW, hopes these efforts will improve traffic, though he is not in favor of the delineators because it would prevent drivers from turning around if waiting on a longer train to pass through.
"There's many times throughout the day that the train blocks the crossing for a half hour to 45 minutes or more. There's also a daycare next door where the kids go to the park in the summertime, and they sometimes have to wait on the hot concrete because they can't get around them," Shirk says.
Rahm says that in addition to reduce the need for trains to sound their horns in these areas, the project was created in order to improve quality of life for nearby residents.
"These folks are living right along the rails, and they're just real tired of hearing the horns blow," Rahm says.
The 4th and 9th street closures will be permanent. The others are expected to last anywhere between 3 to 5 days. This project is expected to be completed by April 22.
According to Rahm, the project will cost about $100,000, but Union Pacific will reimburse up to $85,000.
Mason City will be 1 out of 11 communities in Iowa and over 600 nationwide participating in the Quiet Zone project.
Quiet Zone work to close another road in Mason City
Railroad crossing closed Thursday in Mason City
UPDATE: Railroad officer involved in Mason City shooting
Mason City road closure to start Monday
Road closure starts Monday in Mason City
Investigation continues into Mason City shooting involving railroad police officer
Mason City announces flood damaged item pickup starting Monday
Replacement of Mason City bridge to start Monday
Downtown traffic signal project starts Monday in Mason City


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Памятник Валерию Арсенову — памятник, расположенный в Куйбышевском районе города Донецка.

Установлен 7 сентября 2010 года в сквере возле дома культуры им. Куйбышева.

Памятник посвящён Герою Советского Союза, участнику войны в Республике Афганистан рядовому Арсенову Валерию Викторовичу. Автор памятника Сергей Горбатенко.
Монумент представляет собой композицию, которая состоит из двух стел. На одной изображена карта Афганистана, а на второй находится портрет Валерия Арсенова. Между знамён, в центре, расположен холм славы с фотографиями дончан, погибших в Афганистане. На холме находится чёрный тюльпан, который символизирует транспортные самолёты, доставлявшие на Родину цинковые гробы с телами погибших воинов-интернационалистов («груз 200»).

Характеристики монумента
 Вес — 16 тонн.
 Высота 2,5 метра.
 Диаметр 2,5 метра.

Ссылки
 Памятник воинам-афганцам в Донецке
 В Донецке открыли памятник воину-интернационалисту Валерию Арсенову

арс
Куйбышевский район (Донецк)
Арсенову
Памятники Афганской войны (1979—1989)

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Research ArticleAPPLIED SCIENCES AND ENGINEERING
Bulk layered heterojunction as an efficient electrocatalyst for hydrogen evolution
View ORCID ProfileChangdeuck Bae1,2,*,†,
View ORCID ProfileThi Anh Ho1,*,
Hyunchul Kim1,
Seonhee Lee1,
Seulky Lim1,
Myungjun Kim1,
View ORCID ProfileHyunjun Yoo1,
View ORCID ProfileJosep M. Montero-Moreno3,
Jong Hyeok Park4 and
Hyunjung Shin1,†
1Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Republic of Korea.
2Korean National Research Foundation Shinjin Scientist Program, Sungkyunkwan University, Suwon 440-746, Republic of Korea.
3Institute of Applied Physics, University of Hamburg, Jungiusstrasse 11, 20355 Hamburg, Germany.
4Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, Republic of Korea.
↵†Corresponding author. Email: changdeuck{at}skku.edu (C.B.); hshin{at}skku.edu (H.S.)
↵* These authors contributed equally to this work.
Science Advances 31 Mar 2017:
Vol. 3, no. 3, e1602215
DOI: 10.1126/sciadv.1602215
Changdeuck Bae
ORCID record for Changdeuck Bae
For correspondence: changdeuck@skku.edu hshin@skku.edu
Thi Anh Ho
ORCID record for Thi Anh Ho
Hyunchul Kim
Seonhee Lee
Seulky Lim
Myungjun Kim
Hyunjun Yoo
ORCID record for Hyunjun Yoo
Josep M. Montero-Moreno
ORCID record for Josep M. Montero-Moreno
Jong Hyeok Park
Hyunjung Shin
We describe the spontaneous formation of composite chalcogenide materials that consist of two-dimensional (2D) materials dispersed in bulk and their unusual charge transport properties for application in hydrogen evolution reactions (HERs). When MoS2 as a representative 2D material is deposited on transition metals (such as Cu) in a controlled manner, the sulfidation reactions also occur with the metal. This process results in remarkably unique structures, that is, bulk layered heterojunctions (BLHJs) of Cu–Mo–S that contain MoS2 flakes inside, which are uniformly dispersed in the Cu2S matrix. The resulting structures were expected to induce asymmetric charge transfer via layered frameworks and tested as electrocatalysts for HERs. Upon suitable thermal treatments, the BLHJ surfaces exhibited the efficient HER performance of approximately 10 mA/cm2 at a potential of −0.1 V versus a reversible hydrogen electrode. The Tafel slope was approximately 30 to 40 mV per decade. The present strategy was further generalized by demonstrating the formation of BLHJs on other transition metals, such as Ni. The resulting BLHJs of Ni–Mo–S also showed the remarkable HER performance and the stable operation over 10 days without using Pt counter electrodes by eliminating any possible issues on the Pt contamination.
Electrocatalyst
Hydrogen Evolution Reaction
bulk layered heterojuntion
composite chalcogenide materials
Cu-Mo-S
sequential gas phase deposition
In principle, electrolysis of water into oxygen and hydrogen can offer a clean, renewable energy resource. The cost-effective and efficient splitting of water is a critical issue in technologies and economies with energy delivery systems that use hydrogen, enabling zero emission of greenhouse gases (1). A key challenge in the electrocatalyst design is the performance-cost trade-off of using the platinum-group metals as a cathode for the hydrogen evolution reaction (HER) (2–5). Two different approaches have constituted the major branches of science in this domain of research. One approach is to use less or optimized amounts of precious elements, such as nanoparticulate Pt on carbon supports (6). The other approach is to find new alloy compositions based on Pt. In exploring new alloy composition, computational simulations are beneficial in the development of previously unknown single-phase systems (7, 8). Although more complex surface structures involving platinum have exhibited experimental improvements (9–11), efficient electrocatalysts consisting of nonprecious elements have recently been more actively studied (12–15). Transition metal chalcogenide–based systems, such as MoS2, provide many possibilities for HER because they have unique anisotropic surface/transport properties and provide surfaces with the desired binding energy/site for H+ (16–21). However, a material equivalent to platinum in terms of the onset potential, the Tafel slope, and the long-term stability has not yet been developed.
The activation processes on the catalyst surfaces were believed to be the essential mechanisms for HER, and thus, surface energies matter in the development of HER catalysts with high efficacy. This would be true as for the case of monometallic Pt (22), and seeking platinum-like surfaces seems rational among cost-effective elements. Recent research activities have been headed in this direction accordingly. However, when nonmetallic catalysts are involved, the charge transfer resistance rather than surface reactions themselves would play a significant role and should be considered. A recent study by Voiry et al. (23) experimentally exhibited that the catalytically inert basal plane of 2H MoS2 can be active by controlling the charge transfer resistance of the system. Beyond identifying platinum-like surfaces, we propose here a novel electrocatalytic concept consisting of two-dimensional (2D) materials in bulk; we refer to this concept as the inorganic bulk layered heterojunction (BLHJ). Our approach is based on a simple fabrication technique for the direct growth of MoS2 on self-supported metallic substrates via sequential gas-phase reactions, which result in the spontaneous formation of dense BLHJ structures via spontaneous sulfidation reactions. These structures contain MoS2 flakes, which are dispersed in the Cu2S matrix (resembling "straw in mud plaster"). The present system not only features distinctive inorganic, dense BLHJ structures, which are difficult to prepare experimentally using any other methods, but also has layered 2D materials as the key anisotropic components that trigger unusual charge transfer processes.
We selected MoS2 as the representative 2D component with the feasibility of anisotropic transport properties (17). Incorporating the target layered materials into the bulk chalcogenide host with secure contact interfaces between suitable nanoscale junctions in a controlled manner is difficult (Fig. 1B). We used the sequential gas-phase surface reaction technique for which the reactants, such as Mo or S, are independently delivered into the substrates so that only the surface-limited reactions occur. Because the substrate metal used for the self-supporting electrode is simultaneously sulfidizable, this growth mode is expected to incorporate a layered system into the bulk chalcogenide host. In the design of the BLHJ, another important consideration is to select two chalcogenide systems that are thermodynamically immiscible at given temperatures. For example, copper as the substrate material and Mo for sulfidation will lead to the desired immiscible phase separation to form an inorganic BLHJ with MoS2 at relatively lower temperatures (<300°C) (24). In addition to the formation of thermodynamically immiscible systems, it is Earth-abundant and cheap. Moreover, the quality of Cu as the electrochemical electrode has been verified in the field of battery, and thus, the possible side effects could be ruled out.
Fig. 1 The anisotropic charge transport in the bulk and the spontaneous formation of Cu–Mo–S–based dense nanocomposites during deposition of MoS2 directly on Cu foils.
(A) Illustration of a typical bulk heterojunction (BHJ). A bulk heterojunction consists of particulate/granular structures connected to the electrodes with different chemical potentials (green and red plates). When either electrons or holes are generated, they are then separated isotropically (black arrows). (B) Illustration of the anisotropic charge transport in bulk. The BLHJ concept uses layered chalcogenides inside the bulk chalcogenides. When charges are injected into the layered chalcogenides from one electrode (for example, red plate), they would undergo fast transfer because of the strong anisotropy in the transport properties. (C) Image of the as-grown CMS layers on Cu foil. (D) Plan-view SEM of the as-deposited CMS. (E) Cross-sectional scanning transmission electron microscopy (TEM) image of the resulting CMS layer. (F) Bright-field TEM image of the cross-sectioned TiO2/CMS/Cu, where the topmost layers consist of Pt particles and carbon deposited as protection for focused ion beam sectioning. (G) High-resolution TEM (HR-TEM) image of the Chevrel phase of Cu2.76Mo6S8 formed at the interface of MoS2 and Cu2S. The inset shows that the electron diffraction patterns collected in the dashed orange circle confirm formation of the Chevrel phase. ZA, zone axis.
First, we established the sequential gas-phase surface reaction technique for the precursors on SiO2/Si substrates in a flow-type reactor (about 150 mm in diameter), analogous to the atomic layer deposition (ALD) procedure. To obtain a preliminary result, for example, we used MoCl5 and H2S as the reactants and separated their alternating exposures by N2 purging (fig. S1). The nucleation and growth along the basal planes were strongly affected by the gas flow from the inlet of the chamber (fig. S2). Remarkably, the uniformity of thickness was not maintained across the substrates under the given process conditions (fig. S2). This result has not been reported previously in the context of ALD studies (25, 26), but it is understandable on the basis of the strong structural anisotropy of the resulting materials. The resulting MoS2 layers have distinctive features that are dependent on the distance from the chamber inlet not only in thickness but also in terms of the morphologies (fig. S2D). Larger uniform growth zones were optimized by increasing the pulse time (tp) for MoCl5 (fig. S3), and we used this phenomenon in the present strategy for preparing BLHJ structures.
On the basis of the chemical reaction of MoCl5 and H2S in the gas phase, we suspect that chloride ions are inevitably left in the films during the reaction; thus, the resulting MoS2 nanoflakes incorporate Cl as an impurity. Evidence for the presence of Cl was confirmed by the chemical analysis techniques of energy-dispersive x-ray (EDX) spectroscopy and x-ray photoelectron spectroscopy (XPS) (fig. S4, A to E), although the layered nature was preserved (figs. S4F and S7). Approximately 5 to 10 atomic % of chloride ions were detected. Mott-Schottky measurements revealed the significant amount of negatively charged species, such as Cl ions, that had a density of ~1023/cm3 (fig. S8). This order of magnitude is consistent with the chemical analysis results. The doping density was measured using the Hall measurement technique with van der Pauw geometry and indicates that the Cl dopants are not fully thermally activated (with an electron density of ~1019/cm3; fig. S9). This result is simply a consequence of the low growth temperature (that is, 250°C). In a recent study by Yang et al. (27), this Cl doping was reported to decrease the contact resistance through a significant reduction of the Schottky barrier width. Therefore, the fact that our methodology is intrinsically capable of Cl doping should be beneficial in the design of the present BLHJ structures with efficient charge transport characteristics, as will be discussed later.
The aforementioned processes were used to directly deposit MoS2 onto copper foil (~20 μm in thickness). The corresponding surface reactions were visible across a large area (approximately 10 cm × 10 cm; Fig. 1C). As shown in Fig. 1D, scanning electron microscopy (SEM) image is the representative morphology of the resulting materials on Cu (see fig. S11 for more details). Well-dispersed nanoparticles (bright contrast) embedded in the matrix were observed. A representative scanning transmission electron micrograph shows that the layered structures were densely incorporated into the matrix (that is, CuSx) during the reactions (Fig. 1E). The embodiment of MoS2 and the sulfidation of Cu simultaneously occurred during the fabrication of MoS2, resulting in the formation of CuxS and MoS2 (hereafter termed as CMS), which are immiscible according to their phase diagram at the given temperature (24). The sulfidation of Cu can be understood in the context of the adsorbate-induced surface band bending (28), charge transfer by the H2S molecules, and the subsequent diffusion processes of sulfur inside. We observed a much higher growth rate of CuSx/CMS than that of MoS2 by comparing the resulting thicknesses of MoS2 and CMS layers (fig. S12). The degree of sulfidation of Cu was also affected by the flow during the reaction, as in the case of MoS2, whereas the amounts of MoS2 (determined by detecting Mo) inside the CMS layers remained nearly constant (fig. S12C). This independence offers valuable benefits to the rapid optimization of the MoS2 concentration within the bulk layers when the present system is applied to the HER. Within the thickness gradient investigated, the HER activities showed few differences (fig. S13). A comparison of the resulting thicknesses of the deposited hybrid composites confirmed that we could generate BLHJs of Cu–Mo–S with controlled amounts of MoS2.
The subsequent thermal annealing at 500°C (for ~1 hour under N2 flow; see Materials and Methods for more details) allowed further control over the heterojunction structures of CMS by local alloying at the interfaces between CuxS and MoS2 (fig. S14). Investigation by TEM revealed the formation of Chevrel CuxMo6S8 clusters at the Cu2S/MoS2 interfaces (see the superlattices marked as blue arrows in fig. S15). Notably, according to the bulk phase diagram of the Cu–Mo–S system, alloying CuxMo6S8 is expected at higher temperatures, that is, temperatures greater than ~700°C (24). Therefore, the Chevrel phase formation was understood to be the local alloying effect at the interfaces even upon annealing at 500°C (Fig. 1G). Although their presence was evident in the TEM investigation, the clear detection of the smaller portions of both MoS2 and CuxMo6S8 was limited to the x-ray diffraction (XRD) patterns (fig. S16) (29). Upon being subjected to further heat treatment processes, the Chevrel phase was unambiguously observed to be Cu2.76Mo6S8 in the XRD patterns (fig. S16). Note that the overall distribution of Mo was uniform across the CMS layers (figs. S17 to S19). These observations further imply that the CMS surfaces were also partly terminated by both the MoS2 nanoflakes and the Chevrel clusters, elucidating the CMS/TiO2 interface in detail (fig. S20).
We constructed a conventional three-electrode measurement setup in homemade Teflon cells (fig. S21) using a CMS/Cu cathode, a Pt anode, an Ag/AgCl reference electrode, and a sulfuric acid electrolyte. The cathode was first protected with amorphous TiO2, which was grown by ALD to achieve initial protection (fig. S22, A and B) (30). Notably, this TiO2 coating can initially function as an efficient electronic transport layer for HER (31) and serve the initial activation processes (for example, electrical annealing) of the CMS layers, as will be discussed later. HER activity was investigated at different processing steps and compared with control samples (Fig. 2, A to C). Although Cu and Cu2S themselves exhibit little HER activity under the given measurement conditions, the as-grown CMS that was exhibited substantially enhanced the HER activity. The annealed CMS shows further improvement in the HER. Notably, although the surfaces of Cu2S showed negligible HER activities, the presence of the MoS2 inside certainly contributed to the enhancement of the charge transfer characteristics. After one more junction of TiO2 was added not only as a protective layer but also as an efficient charge transport layer, remarkably, our CMS material exhibited a nearly zero onset potential and a Tafel slope of ~39 mV/decade (dec) (Fig. 2C). These values are comparable with those of our sputtered Pt films and the literature values of Pt (22, 32). To the best of our knowledge, the present study shows the best performance record for HER activities among any other reported materials' systems using nonprecious elements in terms of both the onset potential and the Tafel slope. Note that the resulting high current density did not stem from the large specific surface area and represents the material's property itself. Normalizing the porosity in the HER performance simplifies comparisons among intrinsic properties (32). The roughness factor of our system was estimated to be ~1.3 by electrochemically active surface area with double-layer capacitance measurements (fig. S23). Surface roughness of our planar structure is 5 to 8 nm in root mean square roughness (RRMS) measured by atomic force microscopy (AFM) (fig. S22C). Moreover, the TiO2/CMS/Cu samples were operated stably as HER cathodes for well over a 10-day run at −0.1 V (Fig. 2E). Possible issues on the contamination of Pt were ruled out by carefully analyzing XPS results before and after stability tests (figs. S24 to S26). These superior performances that are comparable with that of Pt were reproducibly observed in samples from four different batches (fig. S27). Nonetheless, a lingering suspicion on the subtle amounts of Pt contamination would be the electrochemical redeposition of Pt during HER under a harsh condition (33) (that is, cycling at larger voltages than −0.1 V versus reversible hydrogen electrode (RHE) used for stability tests, for example, similar to fig. S25). Therefore, we present the HER results by both the conventional three-electrode measurements using Pt counter electrodes as the standard methodology (that is, BLHJ-Ag/AgCl-Pt) and the three-electrode measurements with BLHJ as monolithic electrodes [that is, BLHJ–SCE (saturated calomel electrode)–BLHJ]. The HER results of the CMS layers with a non-Pt counter electrode showed similar performance (fig. S28). How to intrinsically avoid the usage of Pt electrodes will also be demonstrated below with the development of Ni–Mo–S (NMS) systems.
Fig. 2 Electrochemical analysis and HER of the CMS layers.
(A) Linear sweep voltammetry. (B) Onset HER potentials. (C) Tafel curves of the CMS layers (as-grown, cyan; annealed, orange; annealed with TiO2, red) together with those of the control materials (Cu, black; MoS2, green; Pt, blue). (D) Nyquist plots. (E) Chronogalvanometry of MoS2 and CMS/TiO2. The legend colors in (E) are common to all.
A question naturally arises as to what the present mechanisms are. Note that this experimental value of the Tafel slope (around 30 mV/dec) has been observed on Pt(111), assuming extreme coverage of hydrogen and the Tafel reaction (34–36). Our observation might indicate that the rate-determining steps are not simply based on the surface species adsorbed (that is, binding energy matters), but the electron transfer kinetics through the bulk should be seriously considered. One clue is that the impedance analysis exhibited a systematic reduction in the resistance of the whole system as a result of thermal treatment and the addition of distinctive junction interfaces (Fig. 2D). We ascribe the observed high performance for HER to not only the macroscopic mechanism based on band diagrams but also the microscopic structures of our unique system. To measure the work functions of our CMS layers and other control samples, we first complementarily used ultraviolet photoelectron spectroscopy (UPS) (fig. S29). The order of the work function values (Φs) was MoS2 > Cu2S > CMS. This implies the reduction of energy barriers when electrons transfer from the Cu electrode and is consistent with the impedance analysis. The presence of Cl in the MoS2 and its diffusion in the resulting BLHJ structures should be addressed. If the MoS2 flakes are to be formed inside the BLHJs in a similar way, then the Cl-doped MoS2 nanoflakes should contribute to improved transport properties (figs. S5 and S6). The estimated small energy gap from an Arrhenius plot also supports easy processes for the thermal activation of electrons (fig. S10). Therefore, the presence of Cl and the resulting electrical doping effect will play a key role in the charge transfer via the inner frameworks consisting of the MoS2 flakes. Moreover, the XPS results on the annealed CMS would testify a possibility of Cl diffusion into Cu2S if larger amounts of Cl were detected out of the surfaces of CMS than those of MoS2. We observed the higher portions of Cl when compared with those expected in the MoS2 nanoflakes. From this observation, we could therefore conclude the presence of Cl even in the Cu2S matrix, and similar electrical effects, such as a reduction of the Schottky barrier width by doping, are expected. At the interface between TiO2 and electrolytes, both scenarios are possible. One is the transfer via the surface Cu2S because the conduction level of TiO2 is well below that of Cu2S. The other is the transport through the conductive TiO2. The optical absorption measurements were carried out to estimate the bandgap of our TiO2 layers (fig. S30). Although whether the ALD-grown, amorphous TiO2 has direct or indirect transitions is not clear, we believe that the charge transfer mechanism occurs below the conduction band of TiO2 through the defect sites (fig. S31). The detailed transport mechanisms of the ALD-grown, amorphous TiO2 are under debate (37–39). Nonetheless, the coating of TiO2 overlayers resulted in the formation of ideal interfaces with our CMS layers in terms of electron transfer and initial activation. The former is further understood as a framework of the formation of Cu2S/TiO2 ohmic junctions. Notably, all the other control junctions, such as MoS2/TiO2, exhibited no improvement in charge transfer during HER (fig. S32). A very recent report demonstrated that TiO2 layers grown via the same ALD chemistry exhibited significant improvement in electron collection efficacy, with a shift (greater than 0.2 V) of the open-circuit voltage in InP heterojunction solar cells (40). The Cu2S/TiO2 control junctions solely exhibited clear improvement for HER (fig. S32). Note that the amorphous titania layers were not kept on the CMS layers upon long-term operation by detecting no XPS signal of titania (fig. S26). Nevertheless, this layer functioned for initial activation of the underlying CMS layers for long-term stability. We believe that the presence of TiO2 surface layer contributes to the initial charge extraction processes from the CMS BLHJs as follows. We suspect that the long-term operation at the high current density (about tens of microampere per square centimeter) resulted in the electrical annealing of the CMS layers (41), and the performance would become stable possibly by improving the electrical connectivity of the frameworks of MoS2. This argument could be supported by comparing the XPS results after ~100-hour testing (fig. S26) and the chronogalvanometry results for ~10 days (Fig. 2). Moreover, these currents could be further localized for their pass only through the MoS2 frameworks [see the results of conductive AFM (C-AFM) below].
Second, the unique microstructures inside our system are synergistically responsible for the observed HER activity. The local probe measurements on the resulting CMS layer confirmed that the MoS2 nanoflakes were likely manifested in the transport mechanisms. We carried out C-AFM and Kelvin probe force microscopy (KPFM) measurements on the surfaces of the CMS. The potential maps that were thus monitored indicated the successful formation of nanoscale spatial junctions on the surfaces, indicative of the direct modification of the surface energy by embedding 2D materials inside (fig. S33). The local conduction results also imply the presence of selective pathways in the conduction throughout the CMS layers, probably via the MoS2 nanoflakes (Fig. 3, A to C). Notably, these measurements are sensitive to the ideality factor of the junctions between the tip and the sample (42). Our systematic measurements also demonstrate the formation of conductive junction interfaces even at very small loading forces (fig. S34). In addition to the presence of an anisotropic trigger for charge transport, the inhomogeneity in the energy landscape might help evolve H2 because of the asymmetric charge injection for HER. The ingeniously arranged local nucleation in a nanometer/micrometer spatial regions would be beneficial for HERs (43). All these findings result in synergetic contributions in determining the charge transfer kinetics for HER.
Fig. 3 Selectivity of transport properties of the resulting CMS BLHJs.
(A) AFM height image of CMS. (B) Corresponding current map by C-AFM at a sample bias of −0.5 V. (C) Simplified model of BLHJ structures, highlighting localized transport paths of 2D materials (blue). (D) Proposed mechanisms on energy (e) barrier lowering by the localized electric fields.
Therefore, we propose operation principles that might be accountable for the efficient HER performance observed in this study. The present mechanisms have been proposed first by recognizing the fact that the surfaces were mostly terminated by electrocatalytically nonactive materials. Therefore, the classical Volmer-Heyrovsky-Tafel mechanism for HER activity at metal interfaces cannot explain the high HER activity observed here. Although the Tafel reaction having the ideal surface coverage resulted in the theoretical kinetic description to be an ideal Tafel slope of ~30 mV/dec, the estimated Tafel slope of ~39 mV/dec from our BLHJs could not directly assign the rate-determining step (36). As a result, we suggested that the present BLHJ systems have localized transport paths with reduced charge transfer resistance, which serve as the true active site for HER on the basis of the abovementioned observations. By spontaneous sulfidation reactions, followed by heat treatment, the dense BLHJ structures were prepared, and the resulting microstructure exhibited the successful formation of internal networks consisting of the MoS2 and the Chevrel phases. The presence of MoS2 nanoflakes with strong anisotropy inside the bulk can boost the internal transport of charge carriers across the CMS layers inside during the surface reactions. That is, the metal substrate serves as a self-supported cathode, injecting electrons into the CMS layer. In general, the drift and diffusion processes are responsible for the major transport mechanisms during HER. Because the MoS2 is rather confined in the BLHJ, the strong anisotropy should lead to an enhancement in the spatial charge transport via different mechanisms, thereby enabling the design of unique electrocatalysts. Moreover, the mobility of MoS2 is strongly dependent on the dielectric screening of its surroundings (44). The resulting MoS2 nanoflakes were embedded in the Cu2S matrix; thus, this situation should be advantageous to the anisotropic charge transport. As previously discussed, the Cl doping of MoS2 would modify the structures, lower the energy barriers, and shorten the barrier widths with its contact materials, if any (45). Moreover, the Chevrel CuxMo6S8 clusters formed between the MoS2 and Cu2S should facilitate the transfer of charge carriers, operating as gradient junctions. The nanoscale dimensions of the resulting MoS2 flakes in the bulk CMS should lead to the environmental pinning at the Fermi levels inside the bulk and the further lowering of the barrier heights (45). Despite the complex geometries in defining the contact interfaces, the energy band diagrams suggest ideal junction interfaces with negligible barrier heights (fig. S31) (46). As shown in Fig. 3D, the embedded MoS2 flakes can function as sharp tips at the near surfaces and are additionally responsible for energy barrier lowering by the localized fields as proposed mechanisms. The present strategy reported here differs from conventional electrocatalytic concepts that seek the optimum surface binding energy to H+, not only experimentally but also theoretically (table S1). To date, no such electrocatalysts exist, satisfying both the ideal catalyst surface (that is, the onset potential and the Tafel slope) and the long-term stability (fig. S35).
Furthermore, it could offer a general tool to explore other efficient composite electrocatalysts with 2D chalcogenide materials inside the bulk. We applied the present strategy to the porous Ni form as another transition metal where the similar incorporation is expected as well as to the BLHJs of NMS. The difference between Cu and Ni is the cohesive energy (47), and the degree of sulfidation should be different when MoS2 was grown under identical conditions. Because Ni has greater bonding strength than Cu, the formation of NiSx was suppressed and the relative amounts of MoS2 were found to be larger by its spontaneous incorporation as in the CMS case (fig. S36). The BLHJs of NMS also showed the remarkable HER performance without postthermal treatments (Fig. 4). The resulting NMS plates were tested without using Pt counter electrodes to eliminate any possible issues on the trace amount of Pt contamination. Three-electrode measurements [that is, NMS as a working electrode, NMS as a counter electrode, and SCE as a reference] were carried out and exhibited similar performance and superior stability (Fig. 4F). These results explicitly testify that the outstanding HER performance undoubtedly comes from our BLHJ structures. Furthermore, any issues on the contamination of Pt can be completely ruled out by substituting the counter Pt electrode as our NMS, indicative of the technical feasibility of direct utility of the present systems for HERs. The simultaneous incorporation of 2D chalcogenides during sulfidation of desired metals should also open a new path for research in nanocomposites that are currently difficult or not possible to synthesize.
Fig. 4 Electrochemical analysis and HER of the NMS layers.
(A) Polarization curves. (B) Onset HER potentials. (C) Tafel analysis (NMS, red) together with those of the control materials (bare Ni form, gray; sulfurized Ni form, green; Pt, blue). (D) Nyquist plots. The legend colors in (A) are common to all, except for (E). (E) Stability tests of NMS materials both at 10 mA/cm2 and at −0.1 V versus RHE when using Pt as counter electrode for about 100 hours. (F) Long-term stability of our NMS samples for about 1 month where Pt was replaced by the other sheet of NMS (see the inset image).
ALD of MoS2 and TiO2
MoS2 was grown on SiO2/Si substrates at 250°C using a commercially available ALD system (Lucida D100, NCD). MoCl5 (99.6%; Strem Chemicals) and H2S (3.99%, balance N2; JC Gas) were used as reactants. The MoCl5 was kept in a stainless canister at 140°C and delivered into the chamber. Ultrahigh-purity N2 (5 N; JC Gas) was used as both the carrier and the purging gas. The total flow rate was 200 standard cubic centimeters per minute (sccm). A full cycle consisted of tp (MoCl5) of 0.5 to 5 s and tp (H2S) of 1 s, followed by N2 purging for 30 s. The CMS was also prepared using the same configuration with MoS2 on Cu foil (I2B ~20 μm, battery grade, ILJIN Materials). After ALD, the chamber was cooled to room temperature, and the samples were removed from the chamber. Using MoCl5 allowed for sufficient vapor pressure at the low temperature used (that is, 140°C); however, it also resulted in doping by Cl via the following chemical reactions: MoCl5 + H2S ⇄ MoSCl3 + 2HCl and MoSCl3 + H2S ⇄ MoS2Cl + 2HCl.
Once the conditions for growing MoS2 have been established, we further optimized the number of ALD cycles. The progressive improvement was shown in linear sweep voltammetry (fig. S37), and we took 3000-cycle CMS layers in the present study. The annealing conditions have been studied in the temperature range of 300° to 700°C and chosen to give an optimum BLHJ structure (figs. S38 and S39). As-grown CMS samples were annealed in a tube furnace in a flow of inert gas (HTF-Q50, Hantech Co.). The furnace was first evacuated down to less than 3 × 10−2 torr for more than 30 min before introducing 250 sccm of N2 (5 N; JC Gas), and the N2 flow was continuously maintained during annealing. The ramping rate was 5°C/min until the desired temperature increased, and the temperature was kept for 1 hour. The furnace was then cooled down to room temperature naturally.
TiO2 was deposited using a separate, commercial ALD chamber (Ozone, ForALL) at 120°C. Titanium(IV) isopropoxide (TTIP; 99.99%; UP Chemical) and deionized H2O were used as the metal reactant and oxygen source, respectively. The TTIP and water were kept in stainless bubblers at 70°C and room temperature, respectively. A cycle consisted of tp of 2 s for both reactants and Ar (5 N) purging for 8 s at a total flow rate of 200 sccm. The growth rate of TiO2 was determined to be 0.4 Å per cycle.
NMS was synthesized in the same way with CMS except on porous Ni foam (0.8 mm thick; Wellcos Corporation). First, Ni foams were sonicated in ethanol for 30 min and then thermally treated at 800°C for 2 hours under the reducing atmosphere with a mixture gas of 5% H2 in Ar. Three thousand ALD cycles of MoS2 were applied on cleaned Ni foam at 250°C under the identical conditions with the case of CMS.
Structural characterization and surface analysis
The physical dimensions and morphologies were observed by field-emission SEM (JSM7500F, JEOL). The structures were investigated by HR-TEM (JEM 2100F, JEOL) equipped with an EDX spectrometer (AZtec, Oxford Instruments). Thin sections of the samples for TEM were prepared by focused ion beam etching (SMI3050TB, SII). Surface chemical compositions were analyzed using XPS (ESCA Sigma Probe, Thermo VG Scientific), and surface work functions were estimated by UPS (AXIS Ultra DLD, Kratos Inc.) using a He I photon source (hv = 21.2 eV).
Electrochemical measurements
Electrochemical measurements were carried out with a three-electrode system. Pt wires were used as the counter electrode, Ag/AgCl (MF-2052 for H2SO4; Bioanalytical Systems Inc.) as the reference electrode, and the CMS (as controls, Pt, Cu, and MoS2) as working electrodes. The electrochemical properties were recorded using a commercially available potentiostat (VMP-300, Bio-Logic). Cyclic voltammograms were recorded at a scan rate of 5 mV/s either in 0.5 or 1 M H2SO4 electrolyte. The virgin curves were discarded, and the third results were routinely displayed, unless otherwise specified. The polarization curves were replotted as the overpotential (η) versus logarithmic current density, log|j|, to obtain the Tafel slopes. The reference electrode was calibrated to RHE potential in the electrolyte of 1 M H2SO4, that is, E(RHE) = E(Ag/AgCl) + 0.21 V. Electrochemical impedance analysis was carried out at a bias voltage of −0.2 versus Ag/AgCl, in the frequency range from 100 mHz to 100 kHz, at a voltage amplitude of 6 mV, and at room temperature.
NMS was used as both working and counter electrode, and SCE for alkaline electrolytes was used as a reference. The three-electrode configuration with Pt counter electrode was also used for comparison. The reference electrode was calibrated to RHE in the electrolyte of 1 M KOH (pH 14), according to E(RHE) = E(SCE, alkaline) + 0.971 V. Electrochemical impedance analysis was carried out at a bias voltage of −0.2 versus RHE with a voltage amplitude of 10 mV, in the frequency range from 100 mHz to 100 kHz.
Chronoamperometry and chronopotentiometry were carried out at a constant potential of −0.1 V versus RHE and a constant current density of −10 mA/cm2, respectively. Mott-Schottky plots were attained at a frequency of 7.8 Hz, from −0.6 to 0 V versus RHE. The impedance spectroscopy results were analyzed and fitted using EC-Lab software. All the measurements were carried out under dark conditions and mild magnetic stirring (200 rpm, unless otherwise specified).
Local probe measurements
A commercial atomic force microscope (SPA-400, SII) was used for C-AFM and KPFM measurements using Au-coated tips [SI-DF3-A, with a spring constant (C) of ~0.2 N/m; SII NanoTechnology Inc.] and Pt/Ir-coated cantilevers [CONTPt-W, with a resonance frequency (f) of 25 to 27 kHz and C = 1.9 N/m; NanoWorld), respectively. KPFM images were acquired at scan rates of 0.1 to 0.2 Hz with an applied voltage of 1 V (peak-to-peak) and alternating current frequencies near the f value of the cantilevers. We simultaneously measured the topography and surface potential/conduction map of the samples under ambient conditions and in the dark.
Supplementary material for this article is available at http://advances.sciencemag.org/cgi/content/full/3/3/e1602215/DC1
fig. S1. Schematic illustration of the deposition system.
fig. S2. Sequential gas-phase reaction of MoS2 on Si wafers.
fig. S3. Influence of tp of MoCl5 on the uniform growth zone.
fig. S4. Elemental and structural analyses of thin MoS2 films.
fig. S5. Elemental analysis of annealed CMS layers.
fig. S6. High-resolution XPS spectra of the annealed CMS layers in Mo (3d), S (2p), Cu (2p), and Cl (2p) regions.
fig. S7. Raman spectra of MoS2 (300 cycles) grown on Au.
fig. S8. The Mott-Schottky measurement of MoS2 on an Au/Si substrate.
fig. S9. The Hall effect measurements of MoS2 on 500-nm-thick SiO2/Si.
fig. S10. Arrhenius plot of the resistivity from Hall effect measurements on ALD-grown MoS2/SiO2 (500 nm)/Si.
fig. S11. SEM images of the as-grown CMS layers.
fig. S12. Thickness dependence of ALD films and Mo contents as a function of position.
fig. S13. HER activities from the CMS samples with thickness gradient.
fig. S14. Schematic illustration of the structural evolution of BLHJs upon annealing.
fig. S15. Low-magnification TEM micrograph of our CMS layers upon annealing (500°C for ~1 hour under N2 flow) to give an overview of the structures that consist of layered MoS2 and the superstructures of Chevrel clusters (marked by yellow and blue arrows, respectively).
fig. S16. XRD patterns of our CMS on Cu subjected to different thermal treatments.
fig. S17. EDX elemental analysis of our TiO2/CMS/Cu structures.
fig. S18. EDX line scan results for the TiO2/CMS/Cu structures.
fig. S19. Detailed elemental maps of our CMS layers shown in Fig. 1E (main text), indicative of the origin of local variations in the detected elements.
fig. S20. HR-TEM image of annealed CMS to give an overview of the local surface termination.
fig. S21. Schematic of our three-electrode cell used for HER experiments.
fig. S22. Surface morphology of TiO2-coated annealed CMS.
fig. S23. Estimation of electrochemically active surface area of our CMS material by double-layer capacitance measurements.
fig. S24. XPS analyses of CMS materials to check possible contamination of noble metals.
fig. S25. Stability against scanning of the present CMS system (10,000 times).
fig. S26. XPS analyses of TiO2/CMS after stability tests.
fig. S27. Reproducibility tests in the electrocatalytic performance of CMS and NMS materials.
fig. S28. Electrochemical analysis and HER of the CMS layers with a non-Pt counter electrode (that is, graphite).
fig. S29. UPS spectra.
fig. S30. Optical absorption of amorphous TiO2 grown on quartz glass.
fig. S31. Energy band diagrams and the corresponding circuit models of various structures.
fig. S32. HER measurements of our 40-nm-thick TiO2 with different control samples.
fig. S33. KPFM study of our CMS on Cu.
fig. S34. Local transport study of our annealed CMS/Cu samples.
fig. S35. Comparison between our CMS/TiO2 and various HER materials (32) in the electrocatalytic performance.
fig. S36. TEM image of the NMS layer as prepared to give an overview of the structures that densely consist of layered MoS2.
fig. S37. ALD cycle–dependent HER performance of annealed CMS.
fig. S38. HR-TEM image of a CMS layer annealed at 700°C.
fig. S39. Linear sweep voltammetry of the CMS layers annealed at different temperatures.
table S1. Summary of the catalytic performance of various materials for the hydrogen evolution reaction, reported in the literature.
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Acknowledgments: We thank J. Hwang and S. W. Kim for the XRD measurements. Funding: We acknowledge the grant by the Samsung Science and Technology Foundation (SRFC-MA1502-09). Author contributions: C.B. and H.S. conceived the project. C.B. developed the present strategy. C.B., H.K., and T.A.H. prepared the samples. C.B., T.A.H., S. Lee, M.K., J.M.M.-M., J.H.P., and H.S. analyzed the structures. C.B., J.M.M.-M., and T.A.H. carried out the electrochemical experiments. C.B., S. Lim, and H.Y. performed the local probe experiments and analysis. C.B. and H.S. coadvised the research. C.B. wrote the manuscript. All authors reviewed the paper. 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.
Copyright © 2017, The Authors
You are going to email the following Bulk layered heterojunction as an efficient electrocatalyst for hydrogen evolution
By Changdeuck Bae, Thi Anh Ho, Hyunchul Kim, Seonhee Lee, Seulky Lim, Myungjun Kim, Hyunjun Yoo, Josep M. Montero-Moreno, Jong Hyeok Park, Hyunjung Shin
Science Advances 31 Mar 2017 : e1602215
A composite chalcogenide with bulk layered heterojunctions exhibits an excellent catalytic activity for hydrogen production.

redpajama_set_name: RedPajamaCommonCrawl


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She launched the petition on Friday and by last night 839 people had joined her call.
Three of the towers, which have been in Didcot for more than 40 years, will be brought down on Sunday, July 27 Miss Reardon said: "There has been huge excitement in Didcot about the towers coming down. Everyone was expecting to see them, so for them to do it in the dark robs us of our chance to say a final goodbye.
Didcot and Wantage MP Ed Vaizey said: "The towers are much loved, and this will literally be a once in a lifetime opportunity to say farewell.
A spokesman for nPower said: "We have not plucked the time out of thin air. We have consulted with the local council, the Health and Safety Executive and the local police.
He added while the company understood the concerns of residents, safety was its main priority and changing the time was unlikely.


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text:
Lionel Hitchman
Lionel Hitchman was steady, aggressive and defensive-minded defenseman who was often paired with Eddie Shore to form one of the greatest defense tandems in hockey history. Hitchman's flawless defensive play allowed Shore more freedom to play an offensive game, a rarity among rearguards in the early days of hockey. The duo formed a feared one-two defensive punch, with their favorite target being Montreal's Howie Morenz.
Because of his defensive role, Hitchman was an unheralded player. The Toronto-born Hitchman never made an All-Star team and never scored more than 11 points in a season but was integral to the success of the Boston Bruins and prior to that the Ottawa Senators.
"Hitch" started his professional career with the Senators in 1922-23, arriving just in time to play with the legendary Eddie Gerard en route to the playoffs. He played his typical quiet style and even helped the Sens win the Stanley Cup that season.
Though he was a NHL rookie, he played with great composure and dignity. That was never more so evident than in a playoff game against the Montreal Canadiens. Noted goon/superstar Sprague Cleghorn of the Habs cross-checked the lanky Hitchman in the face, knocking out the some of Hitch's teeth and breaking his nose. The foul was so flagrant that not only did the dirty Cleghorn earn a match penalty on the play, but he was suspended by his own team for the final game of the series. Hitch kept on playing, with plaster on his nose, helping the Sens win the NHL title.
The Senators then had to travel west for the Stanley Cup finals where they defeated Vancouver and Edmonton. Frank Patrick, PCHA president, called this year's Senators team the greatest team he had ever seen.
Hitchman was already a player of some notoriety in the Ottawa area before he signed on with the Senators. He had played amateur hockey with the Ottawa New Edinburghs for two seasons while also working as a member of the Royal Canadian Mounted Police.
But it wasn't until he joined the Boston Bruins that he got some recognition of his own. The Bruins, who had long admired his heart and physicality, acquired Hitchman in the 1924-25 season. It seems Ottawa somehow found Hitchman expendable, probably due to the arrival of highly touted local amateur Ed Gorman (who never really amounted to much in the NHL).
Hitchman, who interestingly would become teammates in Boston with his old nemesis Cleghorn, went on to help Boston to its first Stanley Cup final (the B's fell in two games to Hitchman's old Ottawa teammates) with a solid, 3-6-9 campaign in 1926-27. Late in the final loss to Ottawa Hitchman became involved in a brutal fight with former teammate Buck Boucher, drawing a match penalty and $50 fine.
He then added five goals, eight points and a career-high 87 penalty minutes to the cause as Boston finished first in the American Division -- the club's first first-place finish -- in 1927-28. Although the Bruins had players with far more name recognition, Hitchman was named the first captain in the club's modern history that season.
Everything fell into place in 1928-29. Hitchman had a unremarkable offensive season -- one goal, no assists in 38 games, during which he logged 64 penalty minutes --but he led a defense that was virtually impenetrable. The Bruins surrendered only 52 goals over 44 games, then gave up only three more in five playoff games. After a three-game sweep of Montreal in the first playoff round, Hitchman and the B's allowed just one goal in the two-game final with the New York Rangers and claimed the first Stanley Cup in franchise history.
Hitchman matched his regular-season scoring output during the playoffs, contributing the only assist of his post-season career.
Hitchman continued to play the same steady, physical brand of defense through 1933-34, even playing with a broken jaw for part of the 1929-30 campaign. During his 10 seasons on Boston's blue line, the Bruins finished first in the American Division five times (four years in a row between 1928 and 1931) and played in three Cup finals. He played in 377 games as a Bruin, collecting 26 goals and 26 assists for 52 points and 466 penalty minutes. His post-season career included 31 games, three goals, four points and 52 PIMs.
Today fans attending Boston Bruins games will notice Hitchman's number three hanging high in the rafters along side much more familiar hockey legends like Shore, Phil Esposito, Bobby Orr and Cam Neely. Hitchman may be all but forgotten by history, but know this: Hitchman was so good in his day that he became only the second player in NHL history to have his jersey retired.
The late Frank Frederickson would agree Hitchman was one of the all time greats. Frederickson, the Canadian Olympic hero turned Hockey Hall of Famer, once compared Hitchman and his partner Eddie Shore:
"To me, Shore was a country boy who had made good; he was a good skater and puck carrier but was not an exceptional defenseman like his teammate Lionel Hitchman who was better because he could get them coming and going."
Labels: Lionel Hitchman
Unknown, 10:14 AM
I am Fred Hitchman's Great Granddaughter. Thank you for writting this wonderful article.
Jaclyn Eisenmann
Hi Jaclyn - Contact me - I have some things on Fred. This is a wonderful article.
Hi Jaclyn - Contact me - I have some things on Fred. This is a wonderful article. I have his first 178 games with Boston transcribed. This is the 2nd time that I heard about an oldtimer discrediting Shore - Dick Irvin also said Shore was not great defensively -- Many Power Play goals were scored while Shore was in the box also.
heritagelover23@hotmail.com
Hi Jaclyn, i have some large pics of Fred standing on a dock with a woman holding a 27 lb Alantic Salmon.I have a certificate showing the competion that he was in.Believe it or not I have the actual fish that is mounted,on my camp wall. I would like to give it and the pics,to his family.please contact me and I will send you some pics showing these items. I am in Maine, emerydl@comcast.net
Anonymous, 11:04 AM
Not to be snotty but who is Fred?
Jaclyn, I have some pictures that you may be interested in , please contact me @ emerydl@comcast.net
Dave Carignan, 3:36 PM
Just wanted to say this was an awesome article on Hitchman. I write a weekly column for Stanley Cup of Chowder on the history of the Bruins. This week it was on Hitchman and wanted to thank you for some of the information which I read on here. Just wanted to show my appreciation.
Derek, 2:06 PM
Anonymous at 11:04 - His full name was Frederick Lionel Hitchman. Hitch is the best player not in the HHOF.
Derek, 4:45 AM
Of all the early stars Lionel Hitchman should be in the Hockey Hall of Fame. He was constantly credited with being the greatest defenseive defenseman in the game, and was good enough to have his number retired by his Bruins. He appeared in over 400 NHL hockey games, often logging 60 minutes, from 1922 to 1934.
The Windsor Daily Star, October 10th 1936:
Too often in professional sport, the so called "worth" of a performer is measured in terms of his figure showing. In hockey, for example, there are dozens of instances where players have been heralded as great defensemen because of spectacular puck carrying ability and scoring facilities. In fact, the average customer and often the press box observer, has found a "great" tag for a defenseman because of his offensive class. His blocking and his body-checking, his ability to swing dangerous puck-carriers into the corners, are frequently overlooked. If the average defenseman cannot carry a puck successfully, or deliver a spectacular goal on occasion, he is regarded as a poor workman. Lionel Hitchman, who becomes coach of the Boston Bruins this winter, was an exception. Hitchman had a tough time lugging a puck past centre ice. Realizing it himself, he stayed back where he was being paid to play. It took the repeated opinions of Art Ross, Hitchman's mates, and rival snipers who tried to pass him, to convince the general public that "Hitch" really was a "great" defenseman.
Acolades:
In 1939 Marty Burke was asked to name the 6 greatest players in his time in the NHL:
Goal – Hainsworth
Defense – Shore and Hitchman
Center – Howie Morenz
Right Wing – Bill Cook
Left Wing – Aurel Joliat
He rated Hitchman as a greater defenseman than the famous Eddie Shore although he willingly conceded that Shore was more versatile and much more colorful.
Eddie Shore says the hardest hitting defenseman, who really hurt when he hit, was Lionel Hitchman.
In 1943 Bobby Bauer chose his all-time Bruin squad and included Hitchman with Shore.
In 1947 King Clancy said that Sprague Cleghorn was the toughest defenseman he had ever seen and that Lionel Hitchman was the best defensive blue-line patrolman.
Dick Irvin Sr. once said: "Shore was an exciting player to watch, especially when he was carrying the puck. But he often wound up nowhere. Defensively, the guy he was teamed up with, Lionel Hitchman, was better."
Vern Degeer lauds Lionel Hitchman, stellar Boston Bruins defense player, in the following paragraph in the Border Cities Star (Windsor):
"Aspiring major professional hockey defensemen might well pattern their work after the style of Lionel Hitchman of the Boston Bruins, one of the greatest rear-guards in the history of the game. To many qualified hockey judges Hitchman rates ahead of Ivan "Ching" Johnson of the New York Rangers, and Johnson has been regarded as one of the best in the business for several years. You can count on the fingers of one hand the number of times Hitchman goes rushing up the ice. The average cash customer, itching for the thrills of flying skates and neatly executed goals, usually overlooks Hitchman in the excitement. Yet he's the type of defenseman that keeps a job year after year while the more spectacular rearguard is dodging from one club to the other, back to the minors and finaly out of hockey altogether. Hitchman is the lone survivor of a club that has harbored more hockey players over a stretch of eight years than any other professional unit in the history of the game.
As Joe points out this was 77 years ago yesterday. February 22nd 1935.
Unknown, 8:46 AM
I do not understand how, year after year, Frederick Lionel Hitchman is left out of the HHOF!
He was runner up to the hart in 29/30' season. Winner of two stanley cups! Known as one of the best stay at home defenceman of all time!
I believe it is time for Hitchman to go into the Hall of Fame!
Unknown, 7:24 PM
Mr. Hitchman would undoubtedly be surprised, but I hope not displeased, to know that women today play the game that he played so well. My granddaughter, Catie Rose, played D for her Cape Cod high school varsity team this past season proudly wearing number 3, just as her dad did in college. Her style quiet, unheralded, solid, at least to these old eyes. It pleases me that the Bruins retired Mr. Hitchman's number. I will pass the story on to my granddaughter. The memory of such a man shoul live on in the sport. Thomas McNulty.


Hi there. Sorry I have been hit and miss. I'm a realtor and working with a client so have been busy. Lots of papers, more and more papers created by the state most of which a lot of people do not understand. By the time this closes it will be stuffed, my file that is, about two inches high and that is without the loan papers, disclosures and docs in it.
Your password doesnt work on tf? Or that error message?
Molly is in the house.. yo..


The last episode of Conquer Outdoor Equipment's "Hitting the Trail (HTT)" was held in Mt. Apo on December 26-28, 2014 using the Sibulan Trail of Sta. Cruz, Davao del Sur. It was part of the company's drive to scale mountains all over the Philippines which is usually done all year round in a monthly basis featuring different mountain every month.
Delegates from Luzon was composed of eight regular HTT mainstays while there were ten trekkers from Sta. Cruz who joined the expedition, with two rookies joining us in John and Tiffany. Other participants joining me from Sta. Cruz were LOGSAC members Julius Biala, Jonas Florencondia, Tinikaran Outdoor Shop owner Oliver Enot and St. Joseph Runners members James, Jeffrey, Jermel and Romeo.
Just like my previous December climbs, this climb was challenged by the continuous downpour especially since prior to the climb a Low Pressure Area was spotted somewhere in Mindanao region that eventually led to the occurrence of a tropical storm. Unfortunately for those first-timers coming from Luzon, their chase for a sunrise or sunset in the country's highest peak was spoiled. We were instead welcomed by a very strong winds and rain and when we reached the peak the temperature hit beyond the level where our bodies nearly gave up.
We stayed in Tinikaran Campsite 1 on our first night. We had a gradual pace in Day 1 but we shifted gear on the second and third days because of the rain. On the contrasting surface, there was something good that the climb had given me. As I have always been saying, Mt. Apo is a major climbing destination and part of the things that has to be enjoyed includes the weather, the trail and the company and these were exactly the ingredients that shaped a distinct experience of that memorable event.
I have hosted several Mt. Apo climbs in the past as team leader but this climb is something beyond the usual. I was flattered by the good comments uttered from the Manila people, saying the climb was by far one of their most memorable climbs because of the good organization and coordination and the technical personnel handling it from Sta. Cruz.
To Conquer Outdoor Equipment, thank you for this opportunity and we hope to have you climbing Mt. Apo once again in the future. Recognition is also due to Sir Oliver Enot who sponsored the post-climb dinner held at Tajos Beach Resort.
copyright LOGSAC 2011 all rights reserved. Awesome Inc. theme. Theme images by 4x6. Powered by Blogger.


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text:
Q: Click button with Watir can't find button Trying to test a poll vote with Watir.  Just using a script at the moment, and I can't get the script to find the correct button.
HTML (reformatted slightly for readability)
<a href="#" class="btn-poll-short"
            data-action-url="http://url.com/poll/vote.do"
            data-svar="svar1"
            data-type="picture_5569154"
            data-action="a:1" data-socialpollanswer="Yes"
            data-pollid="5569154"
            data-shareanswerpicture=""
            onclick="s_objectID="http://www.url.com/news/world-news/protective-dad-makes-daughter-wear-5568808#_3";return this.s_oc?this.s_oc(e):true">

                Yes
</a>

My method for the click action:
def vote
    browser = Watir::Browser.new
    browser.goto 'http://www.url.com/news/world-news/protective-dad-makes-daughter-wear-5568808'
    sleep 5
    browser.td(:class => 'btn-poll-short').span(:id => 'Yes').click
end

A: Based on your HTML, you should try:
browser.link(:class => 'btn-poll-short').click

or
browser.link(:text => 'Yes').click

In your vote method, you are trying to locate a span within a table cell (instead of a link with a class attribute).

redpajama_set_name: RedPajamaStackExchange


text:
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Frontier fiber-optic internet
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Frontier offers the cheapest internet in the 34610 ZIP with service starting at $27.99/mo. This is significantly less than the average starting price for internet in Spring Hill, $42.59.
Frontier is the largest fiber-optic internet service provider serving the 34610 ZIP code, covering 61% of the city.
What's a good speed for gaming?
Speeds of 10 Mbps and higher are good for gaming, but what you really want to consider when choosing an internet service for gaming is latency, or ping. Latency is the measure of how long it takes for your device to communicate with the server and is the main contributor to lag. The higher the ping, the more likely you are to experience lagging. Shoot for an internet service with latency below 100 ms.
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text:
The McLaurys in Tombstone, Arizona
In the Shadow of Billy the Kid
The Sport of Kings and the Kings of Crime
Conspiracy Theory in America
Why Do They Kill?
A Woman Condemned
The Courtesan and the Gigolo
My Life with Bonnie and Clyde
Iraq/Afghan/Gulf Wars
Tracks To Murder
Jonathan Goodman
Narrated by Darren Roebuck
A witty and informative look at classic American murder cases.
On a 6,000-mile train trip across the North American continent from New York City to the West Coast, then back to New York over a southern route, prizewinning English crime historian Jonathan Goodman visited a number of sites where notorious murders occurred—the Kingsbury Run torso murders in Cleveland; the murder by "thrill-killers" Leopold and Loeb, the St. Valentine's Day Massacre, and the escapades of Al Capone in Chicago; the Henwood-VonPhul-Springer affair in Denver; the murders of Marian Williams and Blanche Lamont in the Emmanuel Baptist Church in San Francisco; and Kate Townsend's murder in New Orleans. Goodman masterfully fuses two literary genres that reach back into the nineteenth century: the true crime essay fathered by Thomas De Quincy and travel reports popularized by Charles Dickens and Mark Twain.
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text:
Das International Fertilizer Development Center (deutsch: Internationales Düngemittelentwicklungszentrum, kurz: IFDC) ist eine internationale Non-Profit-Organisation mit Sitz in Muscle Shoals, Alabama. Die Organisation betreibt Forschung im Bereich der Düngemittelentwicklung und fördert Projekte insbesondere in Entwicklungsländern zur Verbesserung der Ernährungssicherheit durch den Einsatz moderner Düngemittel.

Geschichte
Im April 1974 forderte der damalige Außenminister der Vereinigten Staaten, Henry Kissinger, vor der Generalversammlung der Vereinten Nationen eine Verstärkung der internationalen Bemühungen zur Verbesserung der landwirtschaftlichen Produktion in Entwicklungsländern durch die Nutzung verbesserter Düngemittel. Diese Forderung war auch von der Hungersnot in der Sahelzone zu Beginn der 1970er-Jahre beeinflusst, der zwischen 1968 und 1974 circa eine halbe Million Menschen zum Opfer fielen. Zudem starben bis zu 200.000 Menschen durch eine Hungersnot in Äthiopien in den Jahren 1973 und 1974. Ein Grund für diese Hungersnot war die mangelhafte Versorgung mit Düngemitteln in Folge der Ersten Ölpreiskrise im Jahr 1973. Die Forderung nach einer politischen Reaktion auf diese Ereignisse resultierte unter anderem in der Gründung des IFDC im Oktober 1974.

Im Jahr 1977 wurde die Organisation unter Jimmy Carter, dem damaligen Präsidenten der Vereinigten Staaten, zu einer Internationalen Organisation umgewandelt, zudem wurde im gleichen Jahr das Hauptquartier der IFDC in Muscle Shoals fertiggestellt. Schwerpunkte der Arbeit der Organisation waren zu diesem Zeitpunkt insbesondere Entwicklungsländer in Subsahara-Afrika, aber auch Staaten in Südamerika und auf dem Indischen Subkontinent. Als Reaktion auf die rege Tätigkeit der Organisation in Afrika wurde im Jahr 1987 ein ständiges Büro in Lomé, der Hauptstadt des westafrikanischen Staates Togo, eröffnet. 1989 begann mit einer Trainingsprogramm in Kumasi auch die Schulungstätigkeit des IFDC im Ausland zur Steigerung der Effizienz der Landwirtschaft. Im Jahr 1999 beschäftigte die Organisation 100 Mitarbeiter in Muscle Shoals und 300 Mitarbeiter weltweit. Nach Angaben des damaligen Vorsitzenden Amit Roy wurden zwischen 1974 und 1999 zwischen 200.000 und 300.000 Menschen durch das IFDC geschult.

Im Jahr 2006 war das IFDC an der Durchführung des Afrikanischen Düngemittelgipfels in Abuja unter der Leitung der Afrikanischen Union beteiligt. Als Ergebnis des Gipfels wurde die Erklärung von Abuja verabschiedet, die eine Grüne Revolution zur Steigerung der Effizienz der afrikanischen Landwirtschaft insbesondere durch den Einsatz moderner Düngemittel vorsieht. Nach Angaben der Organisation wurden im Jahr 2009 erstmals mehr als eine Million Menschen in aller Welt bei Veranstaltungen der IFDC geschult, darunter 32 % Frauen. Für die 2020er-Jahre hat die Organisation die Strategie 2020–2030 vorgelegt, die insbesondere die Herausforderungen für die Ernährungssicherheit durch das starke Bevölkerungswachstum in zahlreichen Entwicklungsländern behandelt.

Organisation
Die Organisation des IFDCs beruht auf zwei zentralen Gremien, dem Verwaltungsrat und der Geschäftsführung. Der Verwaltungsrat ist mit Vertretern aus Industrie- und Entwicklungsländern international besetzt, gegenwärtiger Vorsitzender des Rats ist der US-Amerikaner Jimmy Cheek. Insgesamt gehören dem Gremium aktuell 15 Personen an, sieben davon stammen aus den Vereinigten Staaten. Die Geschäftsführung der Non-Profit-Organisation steht seit 2019 Albin Hubscher vor. Zudem gibt es drei Regionaldirektoren, die für drei Weltregionen verantwortlich sind, in denen das IFDC besonders aktiv sind: Nord- und Westafrika, Süd- und Ostafrika sowie Asien. Die Finanzierung der Organisation erfolgt durch Spenden von staatlichen und privaten Geldgebern. Im Rahmen eines jährlichen Berichts informiert die Organisation über die Finanzen und gegenwärtige Projekte. Dem Jahresbericht 2018 zufolge waren die Niederlande und die Vereinigten Staaten 2018 die bedeutendsten Geldgebern der Organisation, des Weiteren kamen finanzielle Zuwendungen unter anderen von der Afrikanischen Entwicklungsbank, der Walmart Foundation und den Vereinten Nationen. Insgesamt wurden im Jahr 2018 auf diese Weise 46,3 Millionen US-Dollar für die Arbeit der Organisation bereitgestellt. Die Ausgaben beliefen sich auf 47,77 Millionen US-Dollar, wobei die Projekte der Organisation in aller Welt mit mehr als 34 Millionen US-Dollar den größten Kostenpunkt darstellten, weit vor der Forschungsarbeit der Organisation mit jährlichen Kosten von knapp drei Millionen US-Dollar.

Aktivitäten
Die Aktivitäten des IFDC gliedern sich in Trainings- und Entwicklungshilfeprojekte in Entwicklungsländern und die Forschungsarbeit der Organisation.

Forschung
Gegenstand der Forschung der Organisation ist die Vereinbarkeit von Bevölkerungswachstum, Ernährungssicherheit und Klimawandel durch einen effizienten Einsatz von Düngemitteln. Die Aktivitäten umfassen dabei die Entwicklung von Düngemitteln, insbesondere in Laboren am Sitz der Organisation in Muscle Shoats, die Überprüfung der Wirkungsweise von Düngemitteln sowie deren Herstellung und Verbreitung, insbesondere in Entwicklungsländern, wo rechtliche Rahmenbedingungen und landwirtschaftliche Expertise teilweise mangelhaft sind. Zudem ist die Organisation an zahlreichen Publikationen und Studien beteiligt. Für Aufsehen sorgte dabei unter anderem eine Schätzung des IFDCs aus dem Jahr 2010 zu den weltweiten Reserven an Phosphor, das für die Düngemittelproduktion von essentieller Bedeutung ist. Demnach waren die weltweiten Reserven circa drei Mal so hoch als nach Angaben der United States Geological Survey. Die Autoren des IFDCs sahen die Versorgung für mehrere Hundert Jahre damit als gesichert an und bestritten die Möglichkeit eines baldigen Peak Phosphor.

Projekte

Nach Angaben der Organisation wurden im Jahr 2018 mehr als eine halbe Million Menschen bei Veranstaltungen des IFDCs geschult, 45 % davon waren Frauen. Außerdem unterhielt die Organisation mehrere lokale Projekte. In neun westafrikanischen Staaten war die Organisation in Zusammenarbeit mit der Westafrikanischen Wirtschaftsgemeinschaft aktiv, ein Schwerpunkt war dabei insbesondere die Steigerung der Effizienz kleiner landwirtschaftlicher Betriebe und die Kooperation mit nationalen Regierungen zur Verbesserung der rechtlichen und wirtschaftlichen Rahmenbedingungen. In Süd- und Ostafrika war die Organisation in Burundi, Äthiopien, Mosambik, Kenia und Uganda aktiv. Dabei wurden unter anderem der Aufbau einer privaten Herstellung von Qualitätssamen in Burundi und die Anpassung der Landwirtschaft in Teilen Mosambiks auf die Veränderungen durch den Klimawandel gefördert. In Asien war die Organisation 2018 in Bangladesch, Myanmar und Nepal aktiv.

Einzelnachweise

Gegründet 1974
Organisation (Land- und Forstwirtschaft, Fischerei)
Organisation (20. Jahrhundert)
Organisation (21. Jahrhundert)
Non-Profit-Organisation
Internationale Organisation


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text:
Q: Small screen menu ( show and hide ) with javascript im learning css and html (my second project )and want a menu on small screen.I copied a code but it didnt really work. The menu dont want to hide its always Showed.I have no knowledge about javascript and need help and explication if you can^^.
this is how its looks on small screen:

var navLinks = document.getElementById("navLinks");

function showMenu() {
  navLinks.style.right = "0";
}

function hideMenu() {
  navLinks.style.right = "-200px";
}
nav {
  display: flex;
  padding: 2% 6%;
  justify-content: space-between;
  align-items: center;
}

nav img {
  width: 150px;
}

.nav-links {
  flex: 1;
  text-align: right;
}

.nav-links ul li {
  display: inline-block;
  position: relative;
  padding: 8px 12px;
}

.nav-links ul li a {
  color: var(--white);
  font-size: 16px;
}

.nav-links ul li a::after {
  content: "";
  width: 0%;
  height: 2px;
  background: var(--primary-500);
  display: block;
  margin: auto;
  transition: width 0.5s;
}

.nav-links ul li:hover a::after {
  width: 100%;
}

/*
        ===============
        TEXT-zone
        ===============a
        */

.text-zone {
  width: 90%;
  color: var(--white);
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
}

.text-zone h1 {
  font-size: 62px;
  font-weight: bold;
}

.text-zone p {
  margin: 10px 0 40px;
  max-width: none;
  font-size: 14px;
}

.hero-btn {
  display: inline-block;
  color: var(--white);
  border: 1px solid var(--white);
  padding: 12px 34px;
  font-size: 13px;
  background: transparent;
  position: relative;
  cursor: pointer;
}

.hero-btn:hover {
  border: 1px solid var(--primary-500);
  background: var(--primary-500);
  transition: var(--transition);
}

nav .fas {
  display: none;
}

@media screen and (max-width: 992px) {
  .text-zone h1 {
    font-size: 24px;
  }
  .nav-links ul li {
    display: block;
  }
  .nav-links {
    position: absolute;
    background: var(--primary-500);
    height: 100vh;
    width: 200px;
    top: 0;
    right: -200px;
    text-align: left;
    z-index: 2;
    transition: var(--transition);
  }
  nav .fas {
    display: block;
    color: var(--white);
    font-size: 22px;
    margin: 10px;
    cursor: pointer;
  }
  .nav-links ul {
    padding: 30px;
  }
}

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A: You just need to add a position-property. I just added in this example: #navLinks { position: fixed; }
Also note:
You should avoid to use .style function in JS in 2021. The modern approach is to use .classList +
.add('class-name') , .remove('class-name') or .toggle('class-name') to apply changes through CSS.
This causes far less issues incl. possible specificity weight issues.

var navLinks = document.getElementById("navLinks");

function showMenu() {
  navLinks.style.right = "0";
}

function hideMenu() {
  navLinks.style.right = "-200px";
}
#navLinks {
  position: fixed;
}

/* for demonstration purpose only */
#navLinks {
  background-color: red;
}

/* original css */
nav {
  display: flex;
  padding: 2% 6%;
  justify-content: space-between;
  align-items: center;
}

nav img {
  width: 150px;
}

.nav-links {
  flex: 1;
  text-align: right;
}

.nav-links ul li {
  display: inline-block;
  position: relative;
  padding: 8px 12px;
}

.nav-links ul li a {
  color: var(--white);
  font-size: 16px;
}

.nav-links ul li a::after {
  content: "";
  width: 0%;
  height: 2px;
  background: var(--primary-500);
  display: block;
  margin: auto;
  transition: width 0.5s;
}

.nav-links ul li:hover a::after {
  width: 100%;
}

/*
        ===============
        TEXT-zone
        ===============a
        */

.text-zone {
  width: 90%;
  color: var(--white);
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
}

.text-zone h1 {
  font-size: 62px;
  font-weight: bold;
}

.text-zone p {
  margin: 10px 0 40px;
  max-width: none;
  font-size: 14px;
}

.hero-btn {
  display: inline-block;
  color: var(--white);
  border: 1px solid var(--white);
  padding: 12px 34px;
  font-size: 13px;
  background: transparent;
  position: relative;
  cursor: pointer;
}

.hero-btn:hover {
  border: 1px solid var(--primary-500);
  background: var(--primary-500);
  transition: var(--transition);
}

nav .fas {
  display: none;
}

@media screen and (max-width: 992px) {
  .text-zone h1 {
    font-size: 24px;
  }
  .nav-links ul li {
    display: block;
  }
  .nav-links {
    position: absolute;
    background: var(--primary-500);
    height: 100vh;
    width: 200px;
    top: 0;
    right: -200px;
    text-align: left;
    z-index: 2;
    transition: var(--transition);
  }
  nav .fas {
    display: block;
    color: var(--white);
    font-size: 22px;
    margin: 10px;
    cursor: pointer;
  }
  .nav-links ul {
    padding: 30px;
  }
}

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