YBB 60432012 PDF EnglishUS$125.00 · In stock · Download in 9 seconds
YBB 60432012: Determination of Boron Oxide Delivery: 9 seconds. True-PDF full-copy in English & invoice will be downloaded + auto-delivered via email. See step-by-step procedure
YBB6:---This is an excerpt. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.), auto-downloaded/delivered in 9 seconds, can be purchased online: https://www.ChineseStandard.net/PDF.aspx/YBB6YBB NATIONAL STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA Determination of boron oxide Determination of boron oxide This method is suitable for the determination of boron trioxide content in various types of medicinal glass packaging materials. This method is to grind and dry the test sample; then melt it with alkali and decompose it with acid. Add calcium carbonate, to make the boron form water-soluble calcium borate, to separate it from other impurity elements. Add mannitol, to quantitatively convert boric acid into alcohol boric acid. Use phenolphthalein as an indicator. Use sodium hydroxide titrant for titration. Calculate the boron trioxide content, based on the volume of sodium hydroxide titrant consumed. Determination method Take the test sample (there shall be no printing). Clean, crush, grind it to fine powder (the particle size shall be less than 100 µm). Dry it at 105 °C ~ 110 °C for 1 hour. Put it in a desiccator, to cool for 1 hour. Take about 0.5 g of fine powder. Weigh it accurately. Put it in a platinum crucible (or silver crucible, nickel crucible). Add 4 g of anhydrous sodium carbonate (or 4 g of sodium hydroxide). Melt and let it cool. Use hot water to wash out the frit, in a 300 mL beaker. Add 20 mL of concentrated hydrochloric acid solution, to decompose the frit. Use a small amount (1→2) of hydrochloric acid, to clean the crucible. Combine the washing liquid in the beaker. After the frit is completely decomposed, use calcium carbonate to neutralize the remaining acid. Add an excess of 4 g of calcium carbonate. Place the beaker in a water bath, to boil it for about 30 minutes. Use qualitative rapid filter paper to filter it. Add a little EDTA (ethylene diamine tetraacetic acid). Boil it. Remove and cool. Add two drops of 0.1% methyl red indicator solution. Use 0.1 mol/L sodium hydroxide and 0.1 mol/L hydrochloric acid, to make the solution neutral (i.e., the solution turns bright yellow). Add 1 mL of 0.1% phenolphthalein indicator and about 2 g ~ 3 g of mannitol. Use 0.1 mol/L sodium hydroxide titration solution, to titrate it to a light red color. Repeat these steps, until the red color does not fade after adding mannitol. Calculation of results (results shall be expressed to two decimal places) ...... Source: Above contents are excerpted from the full-copy PDF -- translated/reviewed by: www.ChineseStandard.net / Wayne Zheng et al. Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of English version of YBB 60432012 be delivered?Answer: The full copy PDF of English version of YBB 60432012 can be downloaded in 9 seconds, and it will also be emailed to you in 9 seconds (double mechanisms to ensure the delivery reliably), with PDF-invoice.Question 2: Can I share the purchased PDF of YBB 60432012_English with my colleagues?Answer: Yes. The purchased PDF of YBB 60432012_English will be deemed to be sold to your employer/organization who actually paid for it, including your colleagues and your employer's intranet.Question 3: Does the price include tax/VAT?Answer: Yes. Our tax invoice, downloaded/delivered in 9 seconds, includes all tax/VAT and complies with 100+ countries' tax regulations (tax exempted in 100+ countries) -- See Avoidance of Double Taxation Agreements (DTAs): List of DTAs signed between Singapore and 100+ countriesQuestion 4: Do you accept my currency other than USD?Answer: Yes. www.ChineseStandard.us -- YBB 60432012 -- Click this link and select your country/currency to pay, the exact amount in your currency will be printed on the invoice. Full PDF will also be downloaded/emailed in 9 seconds.How to buy and download a true PDF of English version of YBB 60432012?A step-by-step guide to download PDF of YBB 60432012_EnglishStep 1: Visit website https://www.ChineseStandard.net (Pay in USD), or https://www.ChineseStandard.us (Pay in any currencies such as Euro, KRW, JPY, AUD).Step 2: Search keyword "YBB 60432012". Step 3: Click "Add to Cart". If multiple PDFs are required, repeat steps 2 and 3 to add up to 12 PDFs to cart. Step 4: Select payment option (Via payment agents Stripe or PayPal). Step 5: Customize Tax Invoice -- Fill up your email etc. Step 6: Click "Checkout". Step 7: Make payment by credit card, PayPal, Google Pay etc. After the payment is completed and in 9 seconds, you will receive 2 emails attached with the purchased PDFs and PDF-invoice, respectively. Step 8: Optional -- Go to download PDF. Step 9: Optional -- Click Open/Download PDF to download PDFs and invoice. See screenshots for above steps: Steps 1~3 Steps 4~6 Step 7 Step 8 Step 9 |
