GB/T 7917.4-1987 PDF English
US$90.00 · In stock · Download in 9 secondsGB/T 7917.4-1987: Standard methods of Hygienic test for cosmetics. Methanol Delivery: 9 seconds. True-PDF full-copy in English & invoice will be downloaded + auto-delivered via email. See step-by-step procedure
Standard ID | Contents [version] | USD | STEP2 | [PDF] delivery | Name of Chinese Standard | Status |
GB/T 7917.4-1987 | English | 90 |
Add to Cart
|
0-9 seconds. Auto-delivery
|
Standard methods of Hygienic test for cosmetics. Methanol
| |
Excerpted PDFs (Download full copy in 9 seconds upon purchase)PDF Preview: GB/T 7917.4-1987
GB/T 7917.4-1987: Standard methods of Hygienic test for cosmetics. Methanol---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/GBT7917.4-1987
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
UDC 668.58.543.062
GB 7917.4-87
Standard method of hygienic test for cosmetics -
Methanol
Issued on. MAY 28, 1987
Implemented on. OCTOBER 01, 1987
Issued by. Ministry of Health of the People's Republic of China
Table of Contents
1 Method summary... 3
2 Sample collection... 3
3 Reagents... 3
4 Instruments... 3
5 Analysis steps... 4
6 Calculation of analysis result... 5
Additional information... 6
Standard method of hygienic test for cosmetics -
Methanol
This Standard applies to the determination of methanol content in cosmetics
that contain ethanol.
1 Method summary
Use gas chromatography to test and quantify the samples directly or after
distillation.
2 Sample collection
See Chapter 2 of GB 7917.1-87, Standard methods of hygienic test for
cosmetics - Mercury.
3 Reagents
3.1 Methanol (99.5%). analytical reagent.
3.2 Methanol-free ethanol. inject 1.0 µl into the chromatograph, there shall be
no impurity peaks.
3.3 GDX-102 (60 ~ 80 mesh). gas chromatography reagent.
3.4 Methanol standard solution. take 2.5 ml of methanol and place it in a 100
ml volumetric flask that is filled with 95 ml of water in advance; then, add water
to the mark; mix well and set aside.
4 Instruments
4.1 Gas chromatograph. it is equipped with hydrogen flame ionization detector.
4.2 Chromatographic column. glass column or stainless-steel column, whose
specification is 2 m × Φ4 mm; it is filled with GDX-102 (60 ~ 80 mesh) supporter.
5 Analysis steps
5.1 Start the chromatograph and make necessary adjustments to achieve the
best working conditions of the instrument.
Chromatographic conditions are selected according to specific conditions; the
reference conditions are.
5.2 Sample pretreatment. for liquid or low-viscosity samples, and when the
methanol content is high, take 10 ml of sample and add methanol-free ethanol
(3.2) to a total volume of 50 ml. If necessary, it can be filtered and used as a
sample liquid. The floral water with low methanol content can also be directly
measured without dilution.
5.3 Determination
Take four 50 ml volumetric flasks; respectively inject 1.00, 2.00, 3.00, 4.00 ml
of methanol standard solution (3.4); then, respectively add 30 ml of methanol-
free ethanol; respectively add water to the mark; this standard sequence
contains methanol of 0.05%, 0.10%, 0,15%, 0.20%.
6 Calculation of analysis result
Calculate the methanol concentration as follows.
...... Source: Above contents are excerpted from the full-copy PDF -- translated/reviewed by: www.ChineseStandard.net / Wayne Zheng et al.
Tips & Frequently Asked QuestionsQuestion 1: How long will the true-PDF of English version of GB/T 7917.4-1987 be delivered?Answer: The full copy PDF of English version of GB/T 7917.4-1987 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 GB/T 7917.4-1987_English with my colleagues?Answer: Yes. The purchased PDF of GB/T 7917.4-1987_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 -- GB/T 7917.4-1987 -- 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 GB/T 7917.4-1987?A step-by-step guide to download PDF of GB/T 7917.4-1987_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 "GB/T 7917.4-1987". 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
|