توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱determinationof free oil in alkylether sulphates by gas chromatography
نویسنده(ها): ، ،
اطلاعات انتشار: دومین همایش علوم و فناوری مواد فعال سطحی و صنایع شوینده، سال
تعداد صفحات: ۴
A quick and simple method is proposed for determination fatty alcohol ethoxylates FAE , which is nonionic surfactant. Because FAE remained during solfonation of alcohol ethoxylated separation and determination of this raw material is important in this study FAE in alkylether sulphates is determined by gas chromatography with a flame ionization detector FID.<\div>

۲Determination of residual monomers in maleic acid\acrylic acid copolymer using in detergents
نویسنده(ها): ، ،
اطلاعات انتشار: سومین همایش علوم و فناوری مواد فعال سطحی و صنایع شوینده، سال
تعداد صفحات: ۴
A quick and simple method, is proposed for determination of residual monomers in maleic acid\acrylic acid copolymer, which used in detergent surfactant. Because maleic and acrylic acid monomers is remained during synthesis of copolymer, separation and determination of this raw materials are important. In this study. Maleic and acrylic acid monomers in copolymer is determined by GC HS Chromatography with a Flame Ionization Detector (FID). The residual monomers of maleic acid and acrylic acid were completely separated and determined in 15 min, and the limits of detection were 3, and 5 mg\L, respectively. The average recoveries were 93.8% – 97% with the relative standard deviations of 3.2% – 4.3%. The correlation coefficients for the linear equations were 0.9987– 0.9991. These results demonstrate that the proposed method is simple, sensitive and reliable for the determination of the residual monomers in maleic acid\acrylic acid copolymer.<\div>

۳Quantitative determination of formaldehyde in cosmeticsusing a solid–phase microextraction–mass spectrometry method
نویسنده(ها): ، ،
اطلاعات انتشار: سومین همایش علوم و فناوری مواد فعال سطحی و صنایع شوینده، سال
تعداد صفحات: ۶
Formaldehyde is a commonly found ingredient in cosmetic products. It is used to preservecosmetic raw materials, or it is liberated by a formaldehyde–donor in consumer products. Based on its hydrophilic property, it is fairly common to find it in watery concoctions like shampoos , conditioners, shower gels, etc.For the assessment of formaldehyde in cosmetics, derivatizations prior to detection by a chromatography or a spectroscopic technique are commonly employed. SPME is a simple, effective adsorption–desorption and environment–friendly technique that eliminates the need for solvents or the aggravation of concentrating volatile or semi–volatile compounds [8]. Controlling and monitoring the analyte parameters of temperature, time and technique are critical to accomplish a quantitatively reproducible SPME result. The contribution of the present work combines the application of the SPME with mass spectrometry for the determination of formaldehyde in shampoo. In this work, formaldehyde is first derivatized with pentafluorophenyl hydrazine (PFPH) in situ. The formed hydrazone is adsorbed over a poly(dimethylsiloxane) divinylbenzene–coated fiber and analyzed using gas chromatography–mass spectrometry. The adsorption–time profiles and salting effect were studied. The precision, recovery and detection limits were determined with spiked samples. The relative standard deviations from different spiked shampoo samples were all less than 10% and the recoveries were between 89.00 and 101.23%. The limit of detection was of 4mg\l. Compared with other techniques, the study shown here provides a simple, fast and reliable method for the analysis of formaldehyde in shampoo.<\div>

۴determination of Glycolic acid, mono– and di chloroacetic acids in betaine by Amino–functionalized SBA–15 as a effective adsorbent
نویسنده(ها): ،
اطلاعات انتشار: کنفرانس بین المللی یافته های نوین پژوهشی در شیمی و مهندسی شیمی، سال
تعداد صفحات: ۹
This paper reports amino–modified ordered mesoporous silica as a new solid phase extractor for determination Glycolic acid, monochloroacetic acid (MCA) and dichloroacetic acid (DCA) in synthetical betaine products. Befor extraction octadecyl silica cartridge was used to reduce the concentration of matrix betaine and a PS–Ag+ pretreatment cartridge was used to remove high Cl− concentration.The amino–modified ordered mesoporous silica (APS–SBA–15) nanoadsorbent exhibited high adsorption affinity for aqueous Glycolate, mono– and dichloroacetate due to the acid and alkaline interactions among the amino functional groups and analytes. Chloroacetates and Glycolate were eluted with 0.8 mol L−1 solution of HClO4 and measured by HPLC with a UV–Vis detector.The effect of pH, flow rate of sample and eluent, type and volume of the eluent were investigated and optimized.At optimum effective parameters, preconcentration factor of 129 was achieved in this method. The detection limits of DCA, MCA and Glycolic acid were 3.7, 13 and 86 ng\L, respectively.<\div>
نمایش نتایج ۱ تا ۴ از میان ۴ نتیجه