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A simple laboratory method for the generation of mixed brominated-chlorinated paraffin single chain mixtures

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Emerging Contaminants 2024年第2期10卷 90-97页

作者： Walter Vetter Clara hägele karin herrmann Tobias Schulz Sina Schweizer University of hohenheim Institute of Food Chemistry(170b)Garbenstr.2870599StuttgartGermany

Brominated-chlorinated paraffins(Br-CPs)are a comparably new compound class that features both Cl and Br atoms on one or several alkane *** to legal restrictions in the use of conventional chlorinated paraffins(CPs),Br-CPs have the potential to become emerging ***,their determination is hampered by the lack of suitable reference ***,we present a simple synthesis procedure with single chain alkanes that leads to Br-CPs with∼4–8 chlorine and 1 to 4 bromine substituents according to gas chromatography with electron capture negative ion mass spectrometry(GC/ECNI-MS).The single-chain Br-CP mixtures were obtained by the shared chlorination and bromination of eight single-chain alkanes(C10 to C17)at two reaction times,*** carbon content of the 16 single-chain Br-CP products,determined by elemental analysis(EA),ranged from 30.8 to 43.8%.The typical hump peak known from CPs was detected with GC with flame ionization detection(GC/FID),electron capture detection(GC/ECD)and GC/*** complexity indicated that low-resolution mass spectrometry is not sufficient for an adequate analysis of Br-CPs.A mathematical formula was developed which allows to calculate all possible combinations of Br and Cl that are in line with the carbon *** proton magnetic resonance spectroscopy(1h NMR)spectra showed similarities to the ones of CPs with one chemical shift range for protons on nonhalogenated carbons and one for protons with one halogen on the same carbon.

关键词： NMR mixtures alkanes

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基于便携式坐标测量机的大齿轮测量方法

光学精密工程 2013年第7期21卷 1763-1770页

作者：林虎 Frank hrtig karin Kniel 石照耀北京工业大学机械工程与应用电子技术学院 Physikalisch-Technische Bundesanstalt Braunschweig und Berlin 38116 BraunschweigGermany

针对目前便携式坐标测量机测量大齿轮的采样策略和评定算法存在的不足,设计了两种特殊的辅助标尺-渐开线标尺及螺旋线标尺。利用设计的两种标尺在大齿轮齿面上对齿廓及螺旋线的测量点进行标注,开展了齿轮的在位重复性测量的实验研究。... 详细信息

针对目前便携式坐标测量机测量大齿轮的采样策略和评定算法存在的不足,设计了两种特殊的辅助标尺-渐开线标尺及螺旋线标尺。利用设计的两种标尺在大齿轮齿面上对齿廓及螺旋线的测量点进行标注,开展了齿轮的在位重复性测量的实验研究。利用关节臂坐标测量机及激光跟踪仪测量系统在德国计量研究院研制的1m外径齿轮样板上开展了测量实验,采用INVOLUTE Pro对采样数据点进行评定,给出了测量结果及测量不确定度。测量实验表明,基于新的齿轮测量方法,关节臂坐标测量机比激光跟踪仪测量系统测量结果更为精确,测试结果与标定值最大相差8.16μm。实验结果验证了提出方法的有效性,为便携式坐标测量机在大齿轮测量领域的应用提供了依据。

关键词：大齿轮测量便携式坐标测量机大齿轮样板

Development of a novel electrospun nanofibrous delivery system for poorly water-soluble β-sitosterol

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Asian Journal of Pharmaceutical Sciences 2016年第4期11卷 500-506页

作者： Urve Paaver Ivo Laidmae hélder A.Santos Jouko Yliruusi Jaan Aruvali karin Kogermann Jyrki heinamaki Faculty of Medicine Department of PharmacyUniversity of TartuNooruse150411 TartuEstonia Faculty of Pharmacy Division of Pharmaceutical Chemistry and TechnologyUniversity of HelsinkiViikinkaari 5EFI-00014HelsinkiFinland Institute of Ecology and Earth Sciences University of TartuRavila 14a50411 TartuEstonia

Electrospinning was used as a novel technique for fabricating polymeric nanofibers of a serum cholesterol lowering and poorly water-soluble plant sterol, β-sitosterol. Chitosan was used as a stabilizer/carrier polymer. The mean diameters of nanofibers ranged from 150 nm to218 nm. β-sitosterol was in an amorphous form and homogeneously dispersed in the nanofibers. The β-sitosterol-loaded nanofibers were freely water-soluble and exhibited very short lag-time in releasing the plant sterol. The dissolution was associated with an immediate recrystallization of β-sitosterol in submicron level. In conclusion, electrospinning is a promising future technology for the formulation of poorly water-soluble plant sterols.

关键词： Electrospinning Plant sterol β-sitosterol Nanofibers Solid-state properties Dissolution

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Impressionism

Impressionism

Determination of REE,U,Тh,Ba,and Zr in simulated hydrogeological leachates by ICP-AES after matrix solvent extraction

作者： karin h. Grimme edited by Norbert Wolf.

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Journal of Rare Earths 2009年第1期27卷 123-127页

作者： Marin Ayranov Joaquin Cobos karin Popa Vincenzo V.Rondinella European Commission Joint Research Centre Institute for Transuranium Elements Postfach 2340 76125 Karlsruhe Germany Paul Scherrer Institut Ch-5232 Villigen PSI Switzerland "Al.I.Cuza"University Department of Chemistry 11-Carol I Blvd. 700506-Ia■i Romania

A fast, reliable and precise method for the determination of Ba, Zr, Th, U, La, Ce, Eu, hf and Gd in leaching solutions containing up to 1 mol/L FeCl3 by inductively coupled plasma-atomic emission spectrometry（ICP-AES） was ***-liquid extraction with diethyl ether was applied for selective and quantitative extraction of the iron with a decontamination factor of *** study has enabled the determination of rare earth elements, U, Th Ba, and Zr, from the solution with high iron content with detection limits in the range of 1-24 ng/ml and a precision of 0.9%-4.6 % relative standard *** developed method was simple and was adopted for implementation in a glove box for handling radioactive materials.

关键词： rare earths elements ICP-AES iron

Advances in active fire detection using a multi-temporal method for next-generation geostationary satellite data

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International Journal of Digital Earth 2019年第9期12卷 1030-1045页

作者： Bryan hally Luke Wallace karin Reinke Simon Jones Andrew Skidmore School of Science RMIT UniversityMelbourneAustralia Bushfire and Natural hazards Cooperative Research Centre MelbourneAustralia Faculty for Geo-Information Science and Earth Observation(ITC) University of TwenteEnschedeNetherlands Department of Environmental Science Macquarie UniversitySydneyAustralia

A vital component of fire detection from remote sensors is the accurateestimation of the background temperature of an area in fire’s absence,assisting in identification and attribution of fire activity. Newgeostationary sensors increase the data available to describebackground temperature in the temporal domain. Broad area methodsto extract the expected diurnal cycle of a pixel using this temporally richdata have shown potential for use in fire detection. This paper describesan application of a method for priming diurnal temperature fitting ofimagery from the Advanced himawari Imager. The BAT method is usedto provide training data for temperature fitting of target pixels, to whichthresholds are applied to detect thermal anomalies in 4 μm imageryover part of Australia. Results show the method detects positive thermalanomalies with respect to the diurnal model in up to 99% of caseswhere fires are also detected by Low Earth Orbiting (LEO) satellite activefire products. In absence of LEO active fire detection, but where aburned area product recorded fire-induced change, this method alsodetected anomalous activity in up to 75% of cases. Potentialimprovements in detection time of up to 6 h over LEO products are alsodemonstrated.

关键词： Fire detection diurnal variation geostationary sensors broad area training advanced himawari imager

石墨烯/聚合物纳米复合材料去除水中废油污染物的研究进展

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新型炭材料 2021年第2期36卷 235-252页

作者：冯昭璇徐亚男岳维勋 karin h.Adolfsson 吴明铂中国石油大学(华东)化学工程学院重质油国家重点实验室山东青岛266580 中国石油大学(华东)新能源学院重质油国家重点实验室山东青岛266580 Department of Fibre and Polymer Technology KTH Royal Institute of TechnologyStockholm 10044

频繁的海上溢油事故和工业含油污水的肆意排放严重破坏海洋生态平衡。因此,开发先进的除油材料迫在眉睫。石墨烯(G)及其衍生物氧化石墨烯(GO)因其具有高比表面积、低密度、高孔隙率、表面功能可调等优异的理化性质,在油水分离领域成为... 详细信息

频繁的海上溢油事故和工业含油污水的肆意排放严重破坏海洋生态平衡。因此,开发先进的除油材料迫在眉睫。石墨烯(G)及其衍生物氧化石墨烯(GO)因其具有高比表面积、低密度、高孔隙率、表面功能可调等优异的理化性质,在油水分离领域成为研究热点。为充分发挥其优势,近年来,将G或GO与聚合物复合制备成功能化G/聚合物或GO/聚合物纳米复合材料,因其具有良好的除油能力、优异的机械性能、价格低廉、形貌及表面化学组分可调等优势而越来越受到人们的青睐。目前已开发出气凝胶、泡沫、海绵、膜等具有三维结构的G/聚合物或GO/聚合物复合吸油剂和过滤膜。本文系统性地总结了从表面润湿理论到G/聚合物或GO/聚合物复合吸油材料和滤膜材料的最新研究进展。此外,重点归纳了近年来有关油品回收及吸油材料再生的方法策略。最后,提出该研究领域目前面临的挑战和未来研究方向,旨在为该领域的深入探索开辟新的视角。

关键词：石墨烯或氧化石墨烯/聚合物复合材料除油吸附剂滤膜表面润湿性

A quantitative analytical method for valienone and its application in the evaluation of valienone production by a breakthrough microbial process

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Chinese Journal of Natural Medicines 2017年第10期15卷 794-800页

作者： CUI Li karin Yanagi ShI Ting LIU Zhang-Min BAI Lin-Quan FENG Yan State Key Laboratory of Microbial Metabolism School of Life Science & Biotechnology and Joint International Research Laboratory of Metabolic & Developmental Sciences Shanghai Jiao Tong University Shanghai 200240 China

Valienone is a significant natural carbasugar member of the C7-cyclitol family as a valuable precursor for glycosidase inhibitor *** is an intermediate of validamycin A biosynthesis pathway and exhibits minimal accumulation in the fermentation broth of the natural Streptomyces producer.A quantitative analytical method is crucial for the development of a breakthrough microbial process overcoming the consumption of the natural metabolic *** present study was designed to develop a pre-column derivatization high-performance liquid chromatography method for quantification of valienone and to help establish a straightforward fermentation process for valienone production by metabolically engineered Streptomyces hygroscopicus *** was derivatized by 2,4-dinitrophenylhydrazine(DNPh)in 10 mmol×L^(-1) h_3PO_4 at 37℃ for 45 min and the derivatives were separated on Eclipse XDB-C18(5 μm,4.6 mm×150 mm)column at 30 °C eluted with 50% acetonitrile for 18 *** derivatives were detected by diode array detector at 380 nm and the configurations of the derivatives were determined by computational *** method was shown to be effective,sensitive,and *** linearity was found in the range of 5–2 000 μg×mL^(-1).The intra-and inter-day precisions were 1.1%–2.7% and 1.7%–2.2%,*** absolute recovery of the spiked samples was 97.2%–102.6%.To date,this is the first reversed-phase high-performance liquid chromatography detection method for valienone in microbial culture *** method successfully helped evaluate the valienone production capability of the engineered Streptomyces hygroscopicus 5008 and could be promising for C7-cyclitol profiling of different engineered mutants combined with the metabonomics methods.

关键词： Valienone Carbasugar Microbial process Derivatization hPLC

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