| Glass-ceramics | t rad (ms) | n              | b            |
| 800degC        | 638+-2.0   | 1.6240+-5x10-5 | 0.63+-5x10-3 |
| 1000degC       | 521+-0.5   | 1.6255+-5x10-5 | 0.63+-5x10-3 |

Caption: Radiative lifetime (trad), refractive index (n) and branching ratio (b) for the glass-ceramics heat-treated at 800 and 1000degC, respectively

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": "638", "type": "Other"}
{"value": "1.6240", "type": "Other"}
{"value": "0.63", "type": "Other"}
{"value": "521", "type": "Other"}
{"value": "1.6255", "type": "Other"}
{"value": "0.63", "type": "Other"}