| Sample name | Nominal composition | Nominal composition | Density, r | Ultrasonic velocity | Ultrasonic velocity | Attenuation, a | Transition temperature T g |
| Sample name | PbO (wt%)           | Bi2O3 (wt%)         | (kgm -3)   | U L ( ms -1 )       | U S ( ms -1 )       | (dBcm -1)      | (degC)                     |
| PBB20       | 20                  | 80                  | 5602.3     | 4075                | 2333                | 0.999          | 258                        |
| PBB30       | 30                  | 70                  | 5554.8     | 3928                | 2247                | 1.163          | 257                        |
| PBB40       | 40                  | 60                  | 5472.1     | 3837                | 2161                | 1.239          | 256                        |
| PBB50       | 50                  | 50                  | 6144.7     | 4013                | 2240                | 1.071          | 257                        |

Caption: Glass composition, density, ultrasonic velocity, attenuation, glass transition temperature (T g), along with sample name of ferroelectric BaTiO3 doped lead bismuth glasses

You are provided with a table from a material science paper. Here are JSON templates for two types of numeric cells: "Other" and "Glass_Compound_Amount":
{"value": "xx", "type": "Other"}
{"value": "xx", "type": "Glass_Compound_Amount", "constituent": "xx", "unit": "xx", "material": "xx"}

Please describe all numeric cells in the above table following the JSON templates (proceeding by row in a left-right, top-down direction). For each cell, output one JSON description per line. For any unanswerable attributes in the templates, set their value to the placeholder "xx".

Cell Description:
{"value": "20", "type": "Glass_Compound_Amount", "constituent": "PbO", "unit": "wt", "material": "PBB20"}
{"value": "80", "type": "Glass_Compound_Amount", "constituent": "Bi2O3", "unit": "wt", "material": "PBB20"}
{"value": "5602.3", "type": "Other"}
{"value": "4075", "type": "Other"}
{"value": "2333", "type": "Other"}
{"value": "0.999", "type": "Other"}
{"value": "258", "type": "Other"}
{"value": "30", "type": "Glass_Compound_Amount", "constituent": "PbO", "unit": "wt", "material": "PBB30"}
{"value": "70", "type": "Glass_Compound_Amount", "constituent": "Bi2O3", "unit": "wt", "material": "PBB30"}
{"value": "5554.8", "type": "Other"}
{"value": "3928", "type": "Other"}
{"value": "2247", "type": "Other"}
{"value": "1.163", "type": "Other"}
{"value": "257", "type": "Other"}
{"value": "40", "type": "Glass_Compound_Amount", "constituent": "PbO", "unit": "wt", "material": "PBB40"}
{"value": "60", "type": "Glass_Compound_Amount", "constituent": "Bi2O3", "unit": "wt", "material": "PBB40"}
{"value": "5472.1", "type": "Other"}
{"value": "3837", "type": "Other"}
{"value": "2161", "type": "Other"}
{"value": "1.239", "type": "Other"}
{"value": "256", "type": "Other"}
{"value": "50", "type": "Glass_Compound_Amount", "constituent": "PbO", "unit": "wt", "material": "PBB50"}
{"value": "50", "type": "Glass_Compound_Amount", "constituent": "Bi2O3", "unit": "wt", "material": "PBB50"}
{"value": "6144.7", "type": "Other"}
{"value": "4013", "type": "Other"}
{"value": "2240", "type": "Other"}
{"value": "1.071", "type": "Other"}
{"value": "257", "type": "Other"}