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Polymerization of norbornene was carried out in the presence of a catalyst system consisting of amidogen substituted mono(η~5-cyclopentadienyl)titanium/methyl aluminoxane.
采用胺基取代单茂钛{Cp~*TiCl_2N[Si(CH_3)_3]_2}与甲基铝氧烷组成催化体系催化降冰片烯聚合，得到有一定结晶结构的、可溶的聚降冰片烯。
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This invention applies mild condition uses substituent group triphenylamine aldehyde or triphenylamine dialdehyde as raw material to react by heating with 2-(5,5-dimethyl-3-vinylcyclohexenyl-2-enylidene)propanedinitrile group to produce the intermolecular charge transfer chromogen with high decomposition temperature, non-coplanar structure, and triphenylamine group.
本发明采用温和的手段，将取代基三苯胺单醛或取代基三苯胺双醛为原料与2-(3，5，5-三甲基环己烯-2-烯亚基)丙二腈共热生成具有高的热分解温度、非共平面空间结构的含三苯胺基团的分子内电荷转移生色团。
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In our research on study chemical reaction of active methylene compounds and brom-acetophenone. Because of brom-acetophenone is compound that contain carbonyl and halogen ,which will take place electrophilic substitution and nucleophilic addition. When active methylene compounds are ethyl acetoacetate and β-diketone, controlling reaction condition, we have found that mono-substitution's production and di-substitution's. production is isolated; active methylene compounds are acetoacetanilide and acetoacetanilide derivate, pyrrolidin-2-one derivants were obtained by substitution and close-ring reaction .but there is no report about it.
本文是让活泼亚甲基类化合物与溴代苯乙酮发生化学反应，由于溴代苯乙酮是含有羰基的卤代烃结构，它可以发生亲电取代和亲核加成反应，当活泼亚甲基类化合物为乙酰乙酸乙酯和β-二酮时，控制反应条件可以发生单取代和双取代两种产物；当活泼亚甲基类化合物为乙酰乙酰芳胺类化合物来反应时，溴代苯乙酮中的羰基与氨基会发生分子内的关环反应生成吡咯烷-2-酮衍生物，这在以前的研究中是没有发现的。
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The factors affect on the degree of substitution of product, yield and apparent viscosity, such as the mol rates of EPTAC with -NH2, reaction temperature, reaction time and the content of water in system have been discussed in detail. FTIR spectrometer and UV spectrometer are used to characterize the structure of the derivative and it is proved that substitution reaction mainly occurs on the -N element .The particle size and morphology of chitosan and quantemary ammonium salt of chitosan are analysised by comparing photos of their scanning electron microscope. The degree of substitution of HACC is determined by acid -base conductometric titration. An error in current formula of DS has pointed out and a correct formula has presented.On the base of experience of above experiment, the reaction conditions of HACC were systematically investigated through orthogonal design, and then the best conditions are found. Water-solubility and dependence of pH are studied.
壳聚糖和环氧丙基三甲基氯化铵在异相条件下发生反应，通过单因素实验，制备了一系列不同性能的壳聚糖季铵盐，本文首次详细讨论了反应条件(反应摩尔比、反应时间、反应温度、水含量)对产率及产物性能的影响；用红外光谱和核磁共振对结构进行表征分析时，发现季铵盐阳离子基以N位上取代为主；通过电镜图片对壳聚糖和季铵盐衍生物外观形貌进行对比，采用酸碱电导滴定法测定产物的取代度，并对常用取代度公式做了修正。
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The more the number of hydroxyl substitution in phenyl ring, the better the ability of scavenging DPPH free radical. That is, trihydroxy is better than dihydroxy, and dihydroxy is better than monohydroxy. Moreover, when the polyhydroxy exists in phenyl ring and it is ortho-position or para-position, the ability of scavenging DPPH free radical is better too.
当苯甲醯基的苯环上羟基取代数量越多，其清除DPPH自由基的能力越好，三羟基效果优於双羟基、单羟基，双羟基效果优於单羟基；而苯甲醯基苯环上若为多羟基且羟基的位置为邻位或对位的关系时，其在清除DPPH自由基的能力较佳。
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This dissertation is mainly focused on the reactivity of methylenecyclopropanes and comprises six parts. 1 The reactions of methylenecyclopropanes with phenylsulfenyl chloride, phenylselenyl chloride and diphenyl diselenide; 2 The coupling reactions of the ring-opening products derivated from methylenecyclopropanes; 3 The palladium-catalyzed ring-enlargement of mono-aryl group substituted methylenecyclopropanes to cyclobutenes. 4 The gold-catalyzed domino ring-opening and ring-closing hydroamination of methylenecyclopropanes with sulfonamides; 5 The Lewis acid-catalyzed reactions of mono-aryl group substituted methylenecyclopropanes with diethyl ketomalonate in the presence of water; 6 The iodobenzene diacetate mediated novel 1,3-dipolar cycloaddition of methylenecyclopropanes, vinylidenecyclopropanes, and methylenecyclobutane with phthalhydrazine.
本论文主要研究了亚甲基环丙烷类化合物的一些化学反应性能，共由以下六部分组成：1、亚甲基环丙烷类化合物与苯硫氯、苯硒氯及二苯基二硒的反应；2、亚甲基环丙烷类化合物开环产物的偶联反应；3、单芳基取代的亚甲基环丙烷类化合物在钯催化剂作用下的扩环反应；4、金化合物催化磺酰胺对亚甲基环丙烷类化合物的串联开环关环氨氢化反应；5、路易斯酸催化亚甲基环丙烷类化合物与丙酮二羧酸二乙酯在有水存在下的反应；6、醋酸碘苯促进的亚甲基环丙烷类化合物、亚乙烯基环丙烷类化合物及亚甲基环丁烷类化合物与邻苯二甲酰肼的新型1，3-偶极环加成反应。
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By means of GPC,IR,GC-MS,~(13)CNMR,~1HNMR,Methylation analysisetc,structural properties of PST-1 were identified as follows:The Mwof PST-1 was 3.44×10~6 Da and its optical rotation was _D~(20)=+0.110°(c0.1, H_2O); PST-1 constituted 8 simple sugars and the molar ratio was 2,4-Dimethoxy-Mannose:Rhamnose:Ara-binose:Xylose:Galactose:D-Galacturonic acid:Mannose:D-glucuronic acid=2%:5%:24%:9%:3%:1%:46%:10%;The chief bone of PST-1 was 1,3,6-linked-β-D-Man residue and the side chains contained Furanoid and Pyranoid residues.
结合GPC、旋光度测定、IR、GC-MS、~(13)CNMR、~1HNMR、高碘酸氧化法、Smith降解以及甲基化方法等分析测试方法，得到PST-1的单糖组成及结构表征，实验结果如下：红豆杉多糖PST-1是重均分子量为3.44×10~6 Da的支链多糖，旋光度为20D=+0.110~0(c0.1，H_2O)；PST-1单糖组成为：2，4-Dimethoxy-Mannose：Rhamnose：Arabinose：Xylose：Galactose：D-Galacturonic acid：Mannose：D-glucuronic acid=2％：5％：24％：9％：3％：1％：46％：10％；PST-1的骨架结构为：具有1，3，6-连接的β-D-甘露糖残基骨架，侧链分枝包括非还原末端的呋喃型α-L-阿拉伯糖残基、吡喃型α-L-阿拉伯糖残基、β-D-木糖残基、β-D-甘露糖残基、2，4-二氧甲基-β-D-甘露糖残基和α-D-葡萄糖醛酸残基；侧链的糖残基也可能存在2，5-二氧-取代呋喃型α-L-阿拉伯糖基、3-氧-取代的β-D-木糖残基、6-氧-取代的α-D-半乳糖醛酸残基、6-氧-取代的α-D-半乳糖残基、4-氧-取代的α-D-葡萄糖醛酸残基和2-氧-取代的α-L-鼠李糖残基，同时后者也可能穿插在主链上。
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In this part, the densities of sodium benzoate, sodium nitrobenzoate, sodium chlorobenzoate and sodium methylbenzoate in DMFwater mixed solvents have been measured at 298.15K with an Anton Paar Model 55 densimeter. From these densities, apparent molar volumes and partial molar volumes have been calculated, transfer volumes from water to DMF-water mixtures and substituent contributions to the transfer volumes have also been obtained. Solvent and substituent effects are discussed in detail. The Scaled Partical Theory has been applied to the ternary solutions to evaluate the partial molar volumes of cavity formation and the volumes change associated with solute-solvent interaction.
选择了含有取代基团的芳香类有机电解质，主要是苯甲酸钠、硝基苯甲酸钠、氯苯甲酸钠和甲基苯甲酸钠的邻、间、对同分异构体作为研究对象，用DMA 55型振荡管密度计测定了它们在不同质量百分数组成的DMF-水混合溶剂中的密度，利用这些密度数据，计算了表观摩尔体积和偏摩尔体积，得到了这些单取代苯甲酸钠从水到DMF-水混合溶剂中的迁移偏摩尔体积及苯环上不同位置的取代基对迁移偏摩尔体积的贡献值，讨论了溶剂效应和取代基效应，并将定标粒子理论应用于此三元电解质溶液中。
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And the ability of antioxidant of polyhydroxy benzamides don't have too many differences with Trolox (IC50 =13.90 μg/ml), the substition of hydroxy group at amino benzene ring doesn't affect the whole ability of antioxidant apparently, but while the single hydroxy group at carboxylic acid benzene ring, they are apparently decrease to scavenge the ability of free radical, as a result, the hydroxy at amino benzene ring substitutes its function, without the hydroxy group, the ability of antioxidant is worst, but it upgrades its function while the hydroxy and amino are in the ortho-position or para-position.
而当多酚醯胺化合物其抗氧化能力与Trolox差不多时(IC50 =13.90 μg/ml)，胺基苯环上之羟基取代对整体抗氧化能力影响不明显，但在羧酸苯环上具单羟基时，其清除自由基能力明显下降，使得胺基苯环上羟基取代发挥了影响力，无羟基取代时，抗氧化能力最差，而羟基与胺基互为邻位或是对位时较间位有提升效果。
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Polymorphism of HLA-DQB1 promoter region in Hans IDDM patients and normal controls have been identified by PCR, PCR/SSCP and PCR/sequencing methods.No differences were found in y and s box between patients and controls carrying different allele as well as in different ethnic groups. There are two different sequences in x box,but CCTAGAGACAGATT sequence locates frequently on the haplotype with DQB1.0302 allele. Polymorphism between transcription point and y box (at position －44～-46 and －59～-61) might be associated with the genetic susceptibility to IDDM. Additionally,a new single base mutant (CACC→CAC A ) was found at position －131 and －128 in two patients carrying DQB1.0601 allele.
结果显示携带不同等位基因的患者与对照者DQB1 5'-调控区y、s box核苷酸序列相同，且与白种人基因结构一致；y box核苷酸序列存在二种结构，CCTAGAGACAGATT序列常常与DQB1.0302等位基因在同一单倍型；转录起始位点至y box间-44至-61位存在多态性，-59至-61位AAG等位基因可能与1-型糖尿病易感相关联；在2例携带DQB1.0601等位基因患者的-131至-128位间发现CACC→ACA A单个碱基取代突变。
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monosubstitution：单基取代
monostalbetrigger单稳态触发器 | monosubstitution单基取代 | Monosulcocypris单槽金星介属