{"id":620213,"date":"2024-11-05T23:38:15","date_gmt":"2024-11-05T23:38:15","guid":{"rendered":"https:\/\/pdfstandards.shop\/product\/uncategorized\/iso-6145-72009\/"},"modified":"2024-11-05T23:38:15","modified_gmt":"2024-11-05T23:38:15","slug":"iso-6145-72009","status":"publish","type":"product","link":"https:\/\/pdfstandards.shop\/product\/publishers\/iso\/iso-6145-72009\/","title":{"rendered":"ISO 6145-7:2009"},"content":{"rendered":"<p>ISO 6145-7:2009 specifies a method for continuous production of calibration gas mixtures, containing two or more components, from pure gases or other gas mixtures by use of commercially available thermal mass-flow controllers. <\/p>\n<p>If this method is employed for the preparation of calibration gas mixtures, the optimum performance is as follows: the relative expanded uncertainty of measurement, <i>U<\/i>, obtained by multiplying the combined standard uncertainty by a coverage factor <i>k<\/i> = 2, is not greater than 2 %.<\/p>\n<p>If pre-mixed gases are used instead of pure gases, mole fractions below 10<sup>&#8211;<\/sup><sup>6<\/sup> can be obtained. The measurement of mass flow is not absolute and the flow controller requires independent calibration.<\/p>\n<p>The merits of the method are that a large quantity of the gas mixture can be prepared on a continuous basis and that multicomponent mixtures can be prepared as readily as binary mixtures if the appropriate number of thermal mass-flow controllers is utilized.<\/p>\n","protected":false},"excerpt":{"rendered":"<p><b>Gas analysis \u2014 Preparation of calibration gas mixtures using dynamic volumetric methods \u2014 Part 7: Thermal mass-flow controllers<\/b><\/p>\n<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\/iso\/\"><b>ISO<\/b><\/a><\/td>\n<td>2009-04<\/td>\n<td>20<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":620225,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[1000,2634],"product_tag":[],"class_list":{"0":"post-620213","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-71-040-40","7":"product_cat-iso","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\/620213","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\/620225"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=620213"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=620213"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=620213"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}