{"id":380094,"date":"2024-10-20T03:05:22","date_gmt":"2024-10-20T03:05:22","guid":{"rendered":"https:\/\/pdfstandards.shop\/product\/uncategorized\/bs-iso-231572021\/"},"modified":"2024-10-26T05:35:12","modified_gmt":"2024-10-26T05:35:12","slug":"bs-iso-231572021","status":"publish","type":"product","link":"https:\/\/pdfstandards.shop\/product\/publishers\/bsi\/bs-iso-231572021\/","title":{"rendered":"BS ISO 23157:2021"},"content":{"rendered":"<p>This document specifies a method for the determination of the silanol group content on the surface of fumed silica by reaction gas chromatographic method.<\/p>\n<h4>PDF Catalog<\/h4>\n<table border=\"1px\" class=\"des-table\">\n<tr>\n<th>PDF Pages<\/th>\n<th>PDF Title<\/th>\n<\/tr>\n<tr>\n<td><b>2<b><\/td>\n<td>National foreword  <\/td>\n<\/tr>\n<tr>\n<td><b>7<b><\/td>\n<td>Foreword  <\/td>\n<\/tr>\n<tr>\n<td><b>8<b><\/td>\n<td>Introduction  <\/td>\n<\/tr>\n<tr>\n<td><b>9<b><\/td>\n<td>1 Scope <br \/> 2 Normative references <br \/> 3 Terms and definitions <br \/> 4 Principle  <\/td>\n<\/tr>\n<tr>\n<td><b>10<b><\/td>\n<td>5 Reagents <br \/> 5.1 General <br \/> 5.2 Toluene <br \/> 5.3 Grignard reagent <br \/> 5.4 Reaction solution <br \/> 5.5 Carrier gas and diluent gas <br \/> 5.6 Auxiliary gases <br \/> 5.7 Calibration substance  <\/td>\n<\/tr>\n<tr>\n<td><b>11<b><\/td>\n<td>6 Apparatus <br \/> 6.1 Gas chromatograph <br \/> 6.2 Headspace system <br \/> 6.3 Oven <br \/> 6.4 Capillary column <br \/> 6.5 Sample vials  <\/td>\n<\/tr>\n<tr>\n<td><b>12<b><\/td>\n<td>6.6 Analytical balance <br \/> 6.7 Gas collecting bag <br \/> 6.8 Syringe <br \/> 7 Sample pre-treatment and reaction <br \/> 7.1 Sample pre-treatment <br \/> 7.1.1 Determination of matter volatile at 105 \u00b0C in fumed silica <br \/> 7.1.2 Preparation of the test sample <br \/> 7.2 Blank test  <\/td>\n<\/tr>\n<tr>\n<td><b>13<b><\/td>\n<td>7.3 Reaction <br \/> 7.4 Analysis <br \/> 7.4.1 Headspace system conditions <br \/> 7.4.2 Gas chromatographic conditions <br \/> 7.4.3 Identification <br \/> 7.4.4 Calibration  <\/td>\n<\/tr>\n<tr>\n<td><b>14<b><\/td>\n<td>7.4.5 Measurement <br \/> 8 Calculation <br \/> 8.1 Calculation of the methane quantity produced in the vials <br \/> 8.2 Calculation of the silanol group content <br \/> 8.2.1 Calculation of fumed silica volatile at 105 \u00b0C <br \/> 8.2.2 Calculation of the silanol group content on the surface of fumed silica  <\/td>\n<\/tr>\n<tr>\n<td><b>15<b><\/td>\n<td>9 Expression of results <br \/> 10 Precision <br \/> 10.1 General <br \/> 10.2 Repeatability limit,  r <br \/> 10.3 Reproducibility limit,  R <br \/> 11 Test report  <\/td>\n<\/tr>\n<tr>\n<td><b>17<b><\/td>\n<td>Annex A (informative) Representative chromatogram of methane  <\/td>\n<\/tr>\n<tr>\n<td><b>18<b><\/td>\n<td>Annex B (informative) Information about precision  <\/td>\n<\/tr>\n<tr>\n<td><b>19<b><\/td>\n<td>Bibliography  <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":"<p><b>Determination of the silanol group content on the surface of fumed silica. Reaction gas chromatographic method<\/b><\/p>\n<table class=\"shortdes-table\" style=\"width: 100%\" border=\"0\" cellspacing=\"0\" cellpadding=\"0\">\n<tbody>\n<tr>\n<td>Published By<\/td>\n<td>Publication Date<\/td>\n<td>Number of Pages<\/td>\n<\/tr>\n<tr>\n<td><a href=\"https:\/\/pdfstandards.shop\/product-category\/publishers\/bsi\/\"><b>BSI<\/b><\/a><\/td>\n<td>2021<\/td>\n<td>20<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":380103,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[1214,2641],"product_tag":[],"class_list":{"0":"post-380094","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-87-060-10","7":"product_cat-bsi","9":"first","10":"instock","11":"sold-individually","12":"shipping-taxable","13":"purchasable","14":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product\/380094","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media\/380103"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=380094"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=380094"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=380094"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}