雪松二醇—（R）—1—苯基甲基硼酸酯（phCHClBO2C15H24）的不对称合成和 …

利用雪松二醇苯基硼酸酯进行不对称合成反应，制得标题化合物并测定结构，其晶体属正交晶系，空间群为Ｐ２１２１２１。结果学参数为：ａ＝５７２８（３），ｂ＝８．５４３（３），ｃ＝４１．２６７（７）Ａ，Ｖ＝２０１９．７Ａ＾３，Ｚ＝４，Ｄｃ＝１．２３ｇ＝ｃｍ＾３，μ（ＣｕＫα）＝１７．７ｃｍ＾－１，Ｒ＝０．００７２，Ｒω＝０．００７７。     

人造芥子油中异硫氰酸烯丙酯与硫氰酸烯丙酯的气相色谱分析

采用２ｍ×３ｍｍ玻璃柱，涂布０．５％ＥＧＡ的８０～１００目ＧａｓｃｈｒｏｍＱ为固定相，以异辛醇为内标物，分析芥子油中异硫氰酸烯丙酯与硫氰酸烯丙酯异构体。该方法既可用于人造芥子油的含量分析，也可用于市售芥子油的质量鉴定。     

薄层色谱法测定对羟基苯甲酸酯合成产物中对羟基苯甲酸酯的产率

１引言对羟基苯甲酸酯类是重要的防腐剂，广泛应用于食品、医药、调味品等。本文在总结前人工作的基础上，以普通的硅胶６０ＧＦ２５４为固定相，苯：乙酸乙酯：冰醋酸（２４：５：０．３）作展开剂，采用薄层色谱法成功地将对羟基苯甲酸甲酯（Ⅰ）、乙酯（Ⅱ）、丙酯（Ⅲ）、丁酯（Ⅳ）合成产物中来反应的酸与其酯分开，并测定了各合成产物中酯的产率，方法简单、快速。２实验部分２．１仪器与试剂岛津ＣＳ－９３０４层色谱扫描仪；岛津λ－２５４ｎｍ紫外灯；美国Ｄｒｕｍｍｏｎｄ公司１μＬ定量毛细管；展开缸为２０ｃｍ×１４ｃｍ×８ｃ…     

3,3‘—四亚甲基—双—（1—苯基—5—吡啶酮—4—羟酸酯）极谱行为研究

ＴＰＰＣ在０．０８ｍｏｌ／ＬＣＨ３ＣＯＯＮａ和０．４ｍｏｌ／ＬＣＨ３ＣＯＯＨ（ＮａＡｃ－ＨＡｃ下同）底液条件下，在电位－１．５７Ｖ附近产生一尖锐的导数波，峰高在３．７×１０＾－６－５．６×１０＾－５ｍｏｌ／Ｌ范围内呈线性关系，同时，讨论了极谱波的性质及电极反应机理。     

丁基罗丹明B—钼酸盐光度法连续测定铈和钪

在聚乙烯醇（ＰＶＡ）存在下，丁基罗丹明Ｂ（ＢＲＢ）分别与铈钼、钪钼杂多酸络阴离子形成离子缔合物，其最大吸收均位于５７０ｎｍ，表面摩尔吸光度分别为εＣｅ＝３．９６×１０＾６Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，εＳｃ＝４．７１×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，服从比耳定律范围分别为０－２４μｇ／Ｌ Ｃｅ和０－６０μｇ／ＬＳｃ，测定极限为Ｃｅ１．０μｇ／Ｌ（ｎ＝１２）和Ｓｃ１．９μｇ／Ｌ（ｎ＝１０），对     

显色剂N—烯丙基—N‘—（氨基对苯磺酸钠）硫脲与钯（Ⅱ）显色反应的研究和…

本报道了极易溶于水的显色剂Ｎ－烯丙基－Ｎ＇－（氨基对苯磺酸钠）硫脲光度法测定钯的条件，：在ＰＨ４．０－５．５缓冲介质中，ＡＳＡＴｕ与钯生成易溶于水的、稳定的黄色络合物，组成比为：Ｐｄ（Ⅲ）：ＡＳＡＴｕ＝１：４；络合物的最大吸收波长为２９６．０ｎｍ表观摩尔吸光系数ε２９６＝１．３３×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１；钯（Ⅱ）在０－２０嗳μｇ／２５ｍＬ呈线性，相关系数γ＝０．９９９５。该法灵敏度     

微乳液介质—1—（2—吡啶偶氮）—2—萘酚光度法测定汽油中环烷酸铁的含量

本研究了微乳液为介质时，铁与１－（２－吡啶偶氮）－２－萘酚（ＰＡＮ）的显色反应。选择７３０ｎｍ处为测定波长，ε为１．４×１０＾４Ｌ．ｍｏｌ＾－＾１．ｃｍ＾－＾１，铁量在０－５０μｇ／２５ｍｌ范围内符合比耳定律，该法适用于汽油中环烷酸铁的测定。     

三环己基锡O,O‘—二（4—氯苯基）—二硫代磷酯酯和二丁基锡双（O,O’—二…

三环己基锡Ｏ，Ｏ’－二（４－氯苯基）二硫代磷酸酯（Ｉ），Ｃ３０Ｈ４１Ｃｌ２（Ｏ２ＰＳ２Ｓｎ，Ｍｒ＝７１８．３６，单斜晶系，Ｐ２１／ｎ，ａ＝１６．１５１（２），ｂ＝９．４１５９（１），ｃ＝２２．９８７（３），Ａ，β＝１０５．６９（１）°，Ｚ＝４，Ｄｃ＝１．４１８ｇ．ｃｍ＾－３，Ｒ＝０．０６３；二丁基锡双（Ｏ，Ｏ’－二（４－甲基苯基）二硫代磷酯酯（Ⅱ），Ｃ３６Ｈ４６Ｏ４Ｐ２Ｓ４Ｓｎ，Ｍｒ＝８５１．６６     

二阶导数红外分光光度法同时定量分析有机酸,酯

本选用有机酸、酯的－（Ｃ＝Ｏ）－红外特征峰作为分析峰，运用二阶导数法消除两分析峰之间的相互干扰，建立了用二阶导数红外分光光度法同时分析同一体系中有机酸、酯含量的新方法，其表观摩尔吸光系数分别为４．４４×１０＾４Ｌ·ｍｏｌ＾－１·ｃｍ＾－１，３．９４×１０＾４Ｌ·ｍｏｌ＾－１·ｃｍ＾－１，体系中的其它物质均不干扰测定。此方法操作简单、重现性好、选择性好，实样测定获得了满意的结果。     

用钼酸盐和罗丹明B连续光度法测定铈和钪

聚乙烯醇存在下，铈或钪钼杂多酸与罗丹明Ｂ（ＲＢ）形成离子缔合物，最大吸收均位于５７０ｎｍ，摩尔吸光系数分别为１．１６×１０＾６和５．６２×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，ｃｍ＾－１，０－１．２μｇ／２５ｍＬＣｅ和０－２．０μｇ／ｍＬＳｃ服从比耳定律，检测限１．５ｎｇ／ｍＬＣｅ（ｎ＝１０）和１．１ｎｇ／ｍＬＳｃ（ｎ＝９）。缔合物的摩尔比为Ｃｅ：ｍＯ：ＲＢ＝１：６：３和 Ｓｃ：Ｍｏ：ＲＢ＝１：１     

Environmentally benign synthesis of β-hydroxy sulfides using cyclic carbonates catalyzed by large-pore zeolites

Abstract

An efficient one-pot synthesis of β-hydroxy sulfides from thiophenol and cyclic carbonates catalyzed by large-pore zeolites has been reported. Reaction of thiophenol with ethylene carbonate in the presence of the Na-X zeolite catalyst gave the highest yield of 2-(phenylthio)ethanol (100%), while reaction with propylene carbonate a highest yield of regioselective product 1-(phenylthio)propan-2-ol was obtained (97%). Enantiomerically pure 1,2-propylene carbonate gave highly regioselective and stereospecific phenylthiopropanol, demonstrating that original chirality of propylene carbonate is retained. A plausible mechanism has been proposed for zeolite-catalyzed transformation involving a chemoselective nucleophilic attack of thiophenoloxide ion onto the less-substituted carbon of cyclic carbonate. The Na-X zeolite catalyst is recyclable and provides advantages of green chemistry approach to the synthesis of β-hydroxy sulfides without the use of any solvent.     

Synthesis and Characterization of Novel Aliphatic Polycarbonates Bearing Pendant Allyl Ether Groups

To fulfill the diverse requirements in surgery and medicine, biomedical polymers have been drawing interests and attentions increasingly since the last decade1. In these fields, aliphatic carbonates have been proved to be a kind of material with excellent…     

PMMA基凝胶聚合物电解质双电层电容器的研究

以碳酸丙烯酯(PC)和碳酸乙烯酯(EC)作增塑剂,LiClO4作支持电解质,高比表面积活性炭为电极,内聚合法制作PMMA-PC+EC-LiClO4体系凝胶聚合物电解质(GPE)双电层电容器.应用交流阻抗、循环伏安、恒流充放电等方法研究了该电容器的性能.结果表明,PMMA-GPE的离子电导率在室温下达3.7 mS.cm-1,电容器的工作电压达3 V,比容量达41.6 F.g-1(I=1 mA.cm-2),等效串联电阻仅为几欧姆.     

聚合电流对锂/聚吡咯电池正极电化学行为的影响

在Pt微盘电极上用恒电流技术在电流密度为0.05-10 mA·cm-2范围合成了1 滋m厚度的聚吡咯(PPy)膜. 采用循环伏安(CV)、计时电势、交流阻抗(EIS)技术考察了不同聚合电流下得到的聚吡咯的电化学行为. 结果表明, 最佳聚合电流区间为1-5 mA·cm-2, 对应的电势一般在3.9-4.1V (vs Li/Li+)之间, PPy的掺杂度为30%左右. 在这一聚合电流密度范围得到的PPy具有较大的电化学容量, 较佳的电化学反应可逆性能、较高的氧化还原电势数值和稳定性能. 处于氧化态的聚吡咯具有优良的导电性. 上述条件下得到的PPy适合于作为锂离子二次电池的正极材料. 适当选择电流, 可以得到有相对完整的共轭仔键的长链结构的PPy 膜.     

全自动电位滴定法测定锂电池原料碳酸锂中主成分的含量

采用全自动电位滴定法测定锂电池原料碳酸锂中主成分的含量,用盐酸标准溶液进行滴定,考虑自动电位滴定仪的灵敏性和准确度,通过多次对比实验,确定了仪器的最佳工作参数、滴定剂浓度和样品称样量等滴定条件;对两个不同品位试样分别进行了11次平行测定,相对标准偏差(RSD)均小于1%。在碳酸锂试样中加入基准物质无水碳酸钠进行碳酸根的加标回收实验,碳酸根的加标回收率在99.4%~100%。与传统的酸碱滴定法相比,全自动电位滴定法方便、快捷,同时方法测定结果准确、可靠、精密度高,适合大批量样品快速分析。     

Radical polymerization behavior of a vinyl monomer bearing five‐membered cyclic carbonate structure and reactions of the obtained polymers with amines

Radical polymerization behavior of a vinyl substituted cyclic carbonate, 4‐phenyl‐5‐vinyl‐1,3‐dioxoran‐2‐one ( 1 ), is described. Radical polymerization of 1 proceeded through selective vinyl polymerization to produce polymers bearing carbonate groups in the side chain, in contrast to that of an oxirane analogue of 1 , 1‐phenyl‐2‐vinyl oxirane that proceeds via the selective ring‐opening fashion. Although the homopolymerization of 1 produce polymers in relatively lower yield, copolymerizations effectively provided cyclic carbonate‐containing copolymers. Nucleophilic addition of primary amines to the resulting homopolymers and copolymers produced the corresponding multifunctional polymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 584–592, 2005     

A New Process for Synthesis of Dimethyl Carbonate from Ethylene Carbonate and Methanol without any Catalyst under Supercritical Conditions

Dimethyl carbonate was synthesized by transesterification reaction between ethylene carbonate and methanol under supercritical conditions without any catalyst. Experimental results showed that the residence time and the molar ratio of methanol to ethylene carbonate all can affect the conversion of ethylene carbonate. When the molar ratio of methanol to ethylene carbonate was 8:1, 81.2% conversion can be achieved at 9.0 MPa and 250℃ after 8 h.     

Pendant cyclic carbonate‐polymer/Na‐smectite nanocomposites via in situ intercalative polymerization and solution intercalation

Nanocomposites of sodium smectite with polyether‐ and polystyrene‐containing pendant cyclic carbonates offer a novel approach to improving hydraulic barrier properties of Na‐smectite liners to saline leachates. The cyclic carbonate polyethers were prepared by cationic ring opening polymerization of a cyclic carbonate‐containing epoxide, whilst polystyrene polymers having pendant cyclic carbonate groups were obtained from radical photopolymerization of styrene. Na‐smectite nanocomposites of these polymers were formed via clay in situ polymerization and solution intercalation methods. X‐ray diffraction (XRD) and FT‐IR analysis confirmed that the polyether can be intercalated within the layers of smectite via in situ as well as solution intercalation of the pre‐formed polymer. The cyclic carbonate polyether nanocomposite was more resistant to leaching in 3M aqueous sodium chloride than its respective cyclic carbonate. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2421–2429     

Catalytic utilization of carbon dioxide to polymer blends via cyclic carbonate

In the present study, the synthesis of bis(cyclic carbonate) from carbon dioxide and bisphenol A (or bisphenol S)-diglycidyl ether was investigated using quaternary ammonium salts as catalyst. Among the salts tested, the one having a larger alkyl group and more nucleophilic counter anion exhibited a better catalytic activity. Poly(hydroxyurethane)s were prepared by the polyaddition reaction of bis(cyclic carbonate) and diamine. The poly(hydroxyurethane) has shown higher thermal stability than conventional polyurethane, and is expected as novel reactive polyurethane. The miscibility of blends containing poly(hydroxyurethena) and poly(styrene-co-acrylonitrile)(SAN) has been also studied by the optical clarity method and DSC.     

全自动电位滴定法测定镍钴锰酸锂中残余的碳酸锂含量

采用自动电位滴定法测定镍钴锰酸锂中残余的碳酸锂含量。试样经搅拌水浸出其中的残余碳酸锂,用盐酸进行滴定。对试样进行11次平行测定,相对标准偏差(RSD)小于3.2%。在镍钴锰酸锂试样中加入基准物质无水碳酸钠进行碳酸根的加标回收实验,碳酸根的加标回收率在97.7%~103%。方法测定结果准确、可靠。