苯乙烯—环氧乙烷嵌段共聚物的阴离子聚合与表征

用二苯甲烷钾为引发剂,阴离子聚合法合成了苯乙烯（Ｓｔ）－环氧乙烷（ＥＯ）嵌段共聚物,并用ＦＴＩＲ,＾１Ｈ－ＮＭＲ,ＳＥＣ,ＷＡＸＤ和动态粘弹谱对共聚物进行了表征。结果表明所得聚合物为分子量可控,窄分布的两嵌段共聚物。     

可生物降解的聚乳酸弹性体的合成与表征

本文将丙交酯（ＤＬ－ＬＡ）与聚乙二醇（ＰＥＧ）的预聚体用甲苯－二异氰酸酯８０（ＴＤＩ）扩链，得到了一系列的聚乳酸（聚醚）型聚氨酯（ＰＥＧ－ＰＬＡ／ＰＵ）弹性体。对预聚体和弹性体分别进行了ＩＲ、ＨＮＭＲ和ＤＭＡ表征，并测定了弹性体的力学性能。结果表明，ＬＡ与ＰＥＧ生成的预聚体是一种三嵌段结构：ＨＯ－ＰＬＡ－ＰＥＧ－ＰＬＡ－ＯＨ。随着ＰＥＧ含量的增加，弹性体的玻璃化温度下降；ＰＥＧ分子量增大时，弹性体     

SiO2-AEO凝胶体系的织构特性

采用溶胶－凝胶法,以正硅酸乙酯（ＴＥＯＳ）为前驱体,用脂肪醇聚氧乙烯醚（ＡＥＯ）为改性剂制备结构可控的多孔ＳｉＯ２干凝胶。结果表明：通过调节添加量和聚合度以及溶胶老化时间可以对ＳｉＯ２干凝胶织构性质进行有效的调控;采用不同的环境气候对ＳｉＯ２－ＡＥＯ干凝胶进行热处理,则ＡＥＯ表现出不同的热稳定性;经热处理后,ＡＥＯ等有机残留物被脱除的同时,ＳｉＯ２－ＡＥＯ干凝胶柔性骨架得到加强,孔分布更趋集中,干     

异丙醇铝改进的原子转移自由基聚合催化体系

以α 溴代异丁酸乙酯［２ （ＥｉＢ） Ｂｒ］ 为引发剂,溴化亚铜（ＣｕＢｒ）／ 联二吡啶（ｂｐｙ）／ 异丙醇铝［Ａｌ（ＯｉＰｒ）３］ 为复合催化剂,在环己酮溶液中进行了甲基丙烯酸正丁酯（ＢＭＡ） 的原子转移自由基聚合（ＡＴＲＰ） ．研究了异丙醇铝对聚合速率及产物分子量分布的影响．异丙醇铝可与引发剂和聚合物中的羰基配位,使相邻的Ｃ—Ｂｒ 键活化,ＡＴＲＰ 反应可以在较低温度下进行．适量溴化铜的加入,可调节ＡＴＲＰ 活性,可得到分子量可控且分子量分布窄的ＰＢＭＡ（ ＭＷＤ＝ １－３ ～１－５） ．     

STUDIES ON GLYCOSIDES XⅢ．──HIGHLY STEREOSELECTIVE SYNTHESIS OF PER－O－BENZYLATED O－，S－α－D－GALACTOPYRANOSIDES AND GALACTOSYL CARBOXYUTES FROM PER－O－BENZYIATED GALACTOSYL TRIFLUOROACETATE

ＳＴＵＤＩＥＳ　ＯＮ　ＧＬＹＣＯＳＩＤＥＳ　ＸⅢ．──ＨＩＧＨＬＹ　ＳＴＥＲＥＯＳＥＬＥＣＴＩＶＥ　ＳＹＮＴＨＥＳＩＳ　ＯＦ　ＰＥＲ－Ｏ－ＢＥＮＺＹＬＡＴＥＤ　Ｏ－，Ｓ－α－Ｄ－ＧＡＬＡＣＴＯＰＹＲＡＮＯＳＩＤＥＳ　ＡＮＤ　ＧＡＬＡＣＴＯＳＹＬ　ＣＡ...     

A NOVEL SYNTHESIS OF α－ARYLSELENO－α－ACYL PHOSPHORANES AND ITS INTRAMOLECULAR WITTIG REACTION

Ａ　ＮＯＶＥＬ　ＳＹＮＴＨＥＳＩＳ　ＯＦ　α－ＡＲＹＬＳＥＬＥＮＯ－α－ＡＣＹＬ　ＰＨＯＳＰＨＯＲＡＮＥＳ　ＡＮＤ　ＩＴＳ　ＩＮＴＲＡＭＯＬＥＣＵＬＡＲ　ＷＩＴＴＩＧ　ＲＥＡＣＴＩＯＮＡＮＯＶＥＬＳＹＮＴＨＥＳＩＳＯＦα－ＡＲＹＬＳＥＬＥＮＯ－α－Ａ...     

STUDY ON THE SYNTHESIS， RING－OPENING REACTION AND GLYCOSIDATION OF 1，6－ANHYDRO－2，4－DI－O－BENZYL－β－D－GLUCOPYRANOSE

ＳＴＵＤＹＯＮＴＨＥＳＹＮＴＨＥＳＩＳ，ＲＩＮＧ－ＯＰＥＮＩＮＧＲＥＡＣＴＩＯＮＡＮＤＧＬＹＣＯＳＩＤＡＴＩＯＮＯＦ１，６－ＡＮＨＹＤＲＯ－２，４－ＤＩ－Ｏ－ＢＥＮＺＹＬ－β－Ｄ－ＧＬＵＣＯＰＹＲＡＮＯＳＥ￥ＨｏｎｇＬＩＡＮＧ；ＣｈａｎｇＰｅｉＦＥＩ...     

A NOVEL REARRRANGEMENT OF as-TRIAZOLIUM SALT TO 5-AMINOIMI DAZOLE DERIVATIVE

Ａ　ＮＯＶＥＬ　ＲＥＡＲＲＲＡＮＧＥＭＥＮＴ　ＯＦ　ａｓ－ＴＲＩＡＺＯＬＩＵＭ　ＳＡＬＴ　ＴＯ　５－ＡＭＩＮＯＩＭＩ　ＤＡＺＯＬＥ　ＤＥＲＩＶＡＴＩＶＥＡＮＯＶＥＬＲＥＡＲＲＲＡＮＧＥＭＥＮＴＯＦａｓ－ＴＲＩＡＺＯＬＩＵＭＳＡＬＴＴＯ５－ＡＭＩＮＯＩ...     

STUDIES ON THE SYNTHESIS AND REACTIONWITH ALKOXIDES OF 3－OXO－1，2－BENZOISOTHIAZOLINE－2－ACETAMIDE1，1－DIOXIDES

ＳＴＵＤＩＥＳＯＮＴＨＥＳＹＮＴＨＥＳＩＳＡＮＤＲＥＡＣＴＩＯＮＷＩＴＨＡＬＫＯＸＩＤＥＳＯＦ３－ＯＸＯ－１，２－ＢＥＮＺＯＩＳＯＴＨＩＡＺＯＬＩＮＥ－２－ＡＣＥＴＡＭＩＤＥ１，１－ＤＩＯＸＩＤＥＳＧｕｏＦｅｎｇＺＨＡＯ；ＨｕａＺｂｅｎｇＹＡＮＧ（Ｉ...     

THE PREPARATION AND CHARACTERIZATION OF ZnO-Ag CORE-SHELL ULTRAFINE PARTICLE

ＴＨＥ　ＰＲＥＰＡＲＡＴＩＯＮ　ＡＮＤ　ＣＨＡＲＡＣＴＥＲＩＺＡＴＩＯＮ　ＯＦ　ＺｎＯ－Ａｇ　ＣＯＲＥ－ＳＨＥＬＬ　ＵＬＴＲＡＦＩＮＥ　ＰＡＲＴＩＣＬＥＴＨＥＰＲＥＰＡＲＡＴＩＯＮＡＮＤＣＨＡＲＡＣＴＥＲＩＺＡＴＩＯＮＯＦＺｎＯ－ＡｇＣＯＲＥ－ＳＨＥ...     

SiO2-AEO凝胶体系的织构特性

采用溶胶 凝胶法 ,以正硅酸乙酯 (TEOS)为前驱体 ,用脂肪醇聚氧乙烯醚 (AEO)为改性剂制备结构可控的多孔SiO2 干凝胶.结果表明 :通过调节添加量和聚合度以及溶胶老化时间可以对SiO2 干凝胶织构性质进行有效的调控 ;采用不同的环境气氛对SiO2 AEO干凝胶进行热处理 ,则AEO表现出不同的热稳定性 ;经热处理后 ,AEO等有机残留物被脱除的同时 ,SiO2 AEO干凝胶柔性骨架得到加强 ,孔分布更趋集中 ,干凝胶结构的热稳定性得到进一步提高.     

脂肪醇聚氧乙烯醚的高温气相色谱法分析

 采用 SE-3 0键合甲基硅酮固定相涂铝石英高温毛细管色谱柱、程序升温、FID检测 ,较好地分离了各种合成及天然脂肪醇聚氧乙烯醚 (AEO)样品中的各组分 ;使用 GC-MS进行了样品中组分的定性 ,并经试验研究采用峰面积归一法进行了组分的定量 ,成功地测定了各种 AEO样品中游离脂肪醇质量分数及聚氧乙烯醚的环氧乙烷 (EO)加成数分布。方法简便、快速 ,有较好的准确度和精密度。     

纳米Ni催化剂在超稠油水热裂解降黏中的应用研究

采用甲基环己烷水正辛醇AEO9形成的微乳液体系制备纳米金属Ni催化剂,并利用该催化剂催化辽河超稠油的水热裂解反应。研究结果表明, 280℃时纳米金属Ni能够促进超稠油的水热裂解反应。与原超稠油相比,反应后样品的硫质量分数由0.45%降到0.23%,胶质、沥青质质量分数分别降低了15.83%、15.33%;GC-MS分析结果表明,甲基环己烷在改质过程中能够脱氢生成甲苯;C、H元素分析结果表明,反应后样品中胶质、沥青质的H/C原子比增加,说明从甲基环己烷上脱下的氢能够转移到超稠油中。表面活性剂AEO9、水和油,在改质结束后的降温过程中,形成了稳定的油包水型乳液,起到乳化降黏作用;而添加的甲基环己烷、正辛醇均能起到稀释降黏作用;在上述降黏作用的协同影响下,反应后样品50℃时的黏度由原来的139800mPa·s降至2400mPa·s,由此表明,纳米Ni催化剂对辽河超稠油水热裂解降黏的催化效果显著。     

Preparative fractionation of nylon 12 by column elution method and gel permeation chromatography

Nylon 12 has a low melting point compared with other commercial products like nylons 6 and 66. Nylon 12 was fractionated by the column elution method at 170.8-C. The same sample was also fractionated by preparative gel permeation chromatography and the molecular weight distribution of the fractions obtained by these methods was similarly determined. The weight-average molecular weight of the fractions was also found by the light scattering method. Both fractionation methods separate the sample according to molecular weight. The former, however, had narrower fractions in molecular weight distribution than the latter and it was easy to obtain a large number of fractions. It was also generally superior in practical use.     

Chemical Composition,Insecticidal and Mosquito Larvicidal Activities of Allspice (Pimenta dioica) Essential Oil

Essential oils are biologically and environmentally safe pesticidal compounds yielded from aromatic plants. Spices are important sources of essential oils, and they are widely used in the medicine, food, and various other industries. Among the different spices, Allspice (Pimenta dioica) is underexplored in terms of its biological efficacy and a limited number of studies are available on the chemical composition of Allspice essential oil (AEO); thus, the present study evaluated the larvicidal property, the repellency, and the fumigant toxicity against common pests of stored products of AEO. AEO was found to inhibit the survival of larvae of such vectors as Aedis, Culex, and Armigeres species. Further, AEO was found to exert repellant effects against the pests of such stored products as Sitophilus, Callosobruchus, and Tribolium. Similarly, the fumigant toxicity was found to be high for AEO against these species. The contact toxicity of AEO was high against Sitophilus and Callosobruchus. Apart from that, the essential oil was found to be safe against a non-target organism (guppy fishes) and was found to be non-genotoxic in an Allium cepa model. Overall, the results of the present study indicate that the essential oil from Allspice could be used as an environmentally safe larvicidal and biopesticidal compound.     

Degradation of lignin by ozone. II. Molecular weights and molecular weight distributions of the alkali-soluble degradation products

The molecular weights and molecular weight distributions of the alkali-soluble degradation products from the ozonolysis of spruce periodate and cuoxam lignins and spruce protolignin have been studied by gel permeation chromatography and ultracentrifugation. The bimodal distribution previously reported for soluble lignins was found to be an artifact; the correct distribution has one broad lowmolecular-weight maximum, with a long tail extending toward the high-molecular-weight end of the distribution. Weight-average molecuar weights of the alkali-soluble degradation products, obtained by sedimentation equilibrium measurements, increased with time of ozonization up to about 15 min. Beyond this time fragmentation of the partly degraded products results in a decrease in molecular weight. Lignin degradation followed the pattern expected of a three-dimensional, infinite-network polymer gel undergoing breakdown. Based on the molecular weights and the molecular weight distributions, a random stepwise mechanism is suggested as the mode of lignin degradation by ozone.     

Effective Components and Molecular Mechanism of Agarwood Essential Oil Inhalation and the Sedative and Hypnotic Effects Based on GC-MS-Qtof and Molecular Docking

Agarwood has been used for the administration of hypnotic therapy. Its aromatic scent induces a relaxed state. However, its aromatic constituents and the underlying molecular effect are still unclear. This study aims to determine the active substance and molecular mechanism of the hypnotic effect of agarwood essential oil (AEO) incense inhalation in insomniac mice. Insomnia models were induced by para-chlorophenylalanine (PCPA, 300 mg/kg) in mice. The sleep-promoting effect was evaluated. Neurotransmitter levels and its receptor were detected to explore the molecular mechanism. The effective components were analyzed by GC-Q/TOF-MS of AEO. The binding mechanisms of the core compounds and core targets were verified by molecular docking. These results showed that AEO inhalation could significantly shorten sleep latency and prolong sleep time, inhibit autonomous activity and exert good sedative and sleep-promoting effects. A mechanistic study showed that AEO inhalation increased the levels of γ-aminobutyric acid (GABA_A), the GABA_A/glutamic acid (Glu) ratio, 5-hydroxytryptamine (5-HT) and adenosine (AD), upregulated the expression levels of GluR1, VGluT1 and 5-HT1A and downregulated 5-HT2A levels. Component analysis showed that the most abundant medicinal compounds were eremophilanes, cadinanes and eudesmanes. Moreover, the docking results showed that the core components stably bind to various receptors. The study demonstrated the bioactive constituents and mechanisms of AEO in its sedative and hypnotic effects and its multicomponent, multitarget and multipathway treatment characteristics in PCPA-induced insomniac mice. These results provide theoretical evidence for insomnia treatment and pharmaceutical product development with AEO.     

Analysis of nonvolatile oxidation products of polypropylene. II. Process degradation

The nonvolatile products of polypropylene that has been process degraded in the melt by a Brabender torque rheometer have been quantitatively identified by infrared analysis and chemical reactions carried out on molded sheets. The molecular weight changes with degradation have been determined by gel-permeation chromatography (GPC). It was determined that there is only one functional group per chain scission instead of the two groups previously found for thermal oxidation in the solid state. The molecular weight distribution is similar, but the functional groups and the general scheme of oxidation differ slightly from those previously found for polyolefin oxidation carried out below the melting point. The functional group distribution differs from that determined in a process-degraded polyethylene sample.     

高效液相色谱质谱法分析脂肪醇聚氧乙烯醚中的碳数及环氧乙烷加成数的分布

应用高效液相色谱法将脂肪醇聚氧乙烯醚按碳数和环氧乙烷加成数 (EO数 )分离后 ,在线联用电喷雾离子化质谱 (ESI MS) ,根据其一系列准分子离子峰判断烷基链长和环氧乙烷聚合度。解释了准分子离子峰强度失真的原因。