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消费品质量安全与人民生活水平、社会经济发展息息相关。消费品质量提升对促进消费品行业发展、改善国内消费环境、提振消费者信心具有重要意义。近年来,随着各种新材料、新配方、新工艺不断投入应用,消费品种类不断推陈出新,为改善消费者的生活品质发挥了重要作用。然而,随之而来的质量安全问题也对消费品检测技术提出了更高的要求和挑战。传统检测方法前处理过程复杂、检测周期长、依赖大型仪器,已不能满足当前经济社会发展的需求,快速检测技术已成为科技工作者关注的重点研究方向。该文综述了近5年来消费品快速检测技术的相关研究工作,对其发展趋势进行了展望,以期为从事相关研究的技术人员提供有益参考。 相似文献
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近期国内外市场相继发生多起消费品因含有重金属、邻苯二甲酸酯增塑剂、致癌芳香胺等有害化学物质而大规模召回的质量安全事件,引致各国陆续发布涉及消费品化学物质的技术性法规和标准,对其中含有的化学物质提出越来越高的要求.该文研究了欧盟、美国和中国等国家涉及玩具、纺织品服装、电子电气产品、家具和食品接触材料等重要消费品的质量安全技术法规的状况及相关的禁(限)用化学物质的要求,并针对检测这些化学物质所涉及的多种最新样品前处理技术和先进仪器分析检测技术进行了综述,以满足其在生产和外贸通关的检验需求. 相似文献
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随着人们生活质量的提高和科学技术的进步,消费品的质量安全已经成为各个国家关注的焦点,很多国家都制定了相应的技术法规来确保本国消费品的质量安全。美国、欧盟等发达国家对消费品中有毒、有害物质的限量正在逐步降低,这就对公共检测机构的技术水平提出了更高的要求,检得出、检得快、检得准,并出具权威、公正、可信、准确的试验报告,必然要求公共检测机构进行严格、规范、科学的质量安全风险管理,以确保公共检测机构对实验室 相似文献
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随着我国经济和人民生活水平的不断提高,作为日常消费品的化妆品产业发展迅猛,其安全性日益受到广泛关注。随之而来的化妆品检测量的大幅增长对检测技术提出了更高的要求。传统样品前处理和检测技术因有机试剂消耗量大,检测通量低、检测周期长已无法满足当前绿色化学发展和高通量检测的需求。对此,科研人员开发了一系列环境友好型前处理技术以及高通量现场快速检测方法,为化妆品质量安全保驾护航。该文综述了当前化妆品样品前处理及检测技术的研究进展,并展望了其发展趋势和应用前景,以期为从事化妆品检测的科研和检验人员提供技术参考。 相似文献
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《理化检验(化学分册)》2017,(3)
<正>随着生活水平的不断提高,人们对消费品质量安全的意识也愈加强烈,从事消费品质量检验的检测机构的潜在风险也愈加突现。作为第三方为社会出具客观、公正的检测数据和结果的检验检测机构,如果提供的报告数据和结果有误,将对社会公众产生严重误导,也会对机构的自身信誉造成严重损坏。因此,检验检测机构必须建立科学合理的风险管理体系,严格、规范地管控所面临的潜在风险,并采取 相似文献
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用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%. 相似文献
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Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields. 相似文献
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Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction
Laurent Gavara Thomas Boisse Jean-Pierre Hénichart Adam Daïch Philippe Gautret 《Tetrahedron》2010,66(38):7544-5571
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments. 相似文献
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The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula. 相似文献
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Rebecca J. Burton Mandy L. CrowtherNeal J. Fazakerley Shaun M. FilleryBarry M. Hayter Jason G. KettleCaroline A. McMillan Paula PerkinsPeter Robins Peter M. SmithEmma J. Williams Gail L. Wrigley 《Tetrahedron letters》2013
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines. 相似文献
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KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields. 相似文献
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N. A. Nedolya 《Chemistry of Heterocyclic Compounds》2008,44(10):1165-1219
The review contains a concise historical account and information on the most significant researches undertaken by the staff
at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry
of Heterocyclic Compounds.
Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008. 相似文献
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A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL. 相似文献
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Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products. 相似文献
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A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions. 相似文献