八苄基蔗糖及其水解反应产物的制备

研究了八苄基蔗糖制备的新方法及其水解反应。通过对蔗糖乙酰化保护得到八乙酸蔗糖酯,再经BnCl、KOH反应得到八苄基保护的蔗糖,总收率81%。八苄基蔗糖在乙酸和硫酸溶液中水解得到2,3,4,6-四-O-苄基葡萄糖和1,3,4,6-四-O-苄基果糖,收率分别为29%和25%。产物结构经1HNMR确证。     

高纯度药用级蔗糖八硫酸酯钠的制备工艺研究

采用无水吡啶为催化剂可以有效地提高蔗糖八硫酸酯钠的产率及成品的纯度，探讨反应条件对结果的影响，得出最佳反应条件为：n（蔗糖）：n(三氧化硫-吡啶复化物)：n(催化剂)=1:6:11，保温时间为4 h，反应温度为80℃～90℃。采用醇-水重结晶的方法对粗产物进行提纯，重结晶两次后蔗糖八硫酸酯钠纯度可达99.8%，继续重结晶对纯度提高影响不大。同时开发了蔗糖八硫酸酯钠含量的检测方法。高纯度蔗糖八硫酸酯钠作为药用辅料满足高端药物制剂的需求。     

KF/γ-Al_2O_3制备条件对催化合成八乙酸蔗糖酯的影响

用KF/γ-Al2O3为催化剂合成八乙酸蔗糖酯,研究了KF负载量、焙烧温度、焙烧时间对催化剂活性的影响,得到了较佳制备条件为:KF负载量25%、焙烧温度600℃、焙烧时间6 h。八乙酸蔗糖酯产率最高可达86.2%。产品经熔点和IR测试,证实了自制产品与美国产品的纯度基本一致。     

具有杀虫活性蔗糖酯的合成

分别以酯交换法和酰氯法合成了辛酸蔗糖酯和己酸蔗糖酯两种杀虫活性蔗糖酯,其中酯交换法产物单酯含量高,而酰氯法反应速度快。实验在n(蔗糖):n(辛酸乙酯)=2:1,DMF为溶剂,碳酸钾为催化剂,(98±2)℃条件下反应16 h制备了辛酸蔗糖酯,辛酸乙酯的转化率为68．5％(多酯按二酯计算,下同);在n(蔗糖):n(己酰氯)=2:1,DMF为溶剂、吡啶为助剂,65℃条件下反应1．5 h制备了己酸蔗糖酯,己酰氯的转化率为53．9％。产物经傅里叶红外光谱分析、薄层层析分离和分光光度分析,确定辛酸蔗糖酯和己酸蔗糖酯中n(单酯):n(多酯) 分别为1．48:1和1．37:1。以P(辛酸蔗糖酯)=4 mg／mL水溶液对舞毒蛾(Lymantria dispar)1龄幼虫进行杀虫实验,触杀方式36 h后校正死亡率达72．5％。     

蔗糖脂肪酸酯的合成

以蔗糖和硬脂酸乙酯为原料合成蔗糖酯.讨论了原料配比、时间、皂含量、催化剂用量及配比对蔗糖酯得率的影响,得到最优条件：蔗糖/硬脂酸乙酯=1/0.8,反应5 h,加入6%的脂肪酸皂和7%的催化剂,乙醇钠/碳酸钾=1/4;反应温度130～135℃.     

TiGeW_(12)O_(40)/TiO_2微乳化法合成蔗糖酯

以硬脂酸甲酯与蔗糖为原料,在催化剂TiGeW12O40/TiO2和乳化剂的作用下进行酯交换反应合成蔗糖酯,详细考察了乳化剂和催化剂用量、反应温度、原料配比等因素对合成蔗糖酯的影响。结果表明,较佳合成工艺条件为:硬脂酸甲酯∶蔗糖(摩尔比)=2∶1,乳化剂选用十二烷基硫酸钠,用量为投放总量的6%,催化剂占总质量的1.5%,反应温度120～130℃,反应时间3h,得到一酯,二酯的混合蔗糖酯。     

蔗糖邻苯二甲酸单酯的合成研究

采用TIC跟踪反应,对蔗糖邻苯二甲酸单酯的合成方法进行了系统研究.实验以蔗糖与邻苯二甲酸酐为原料,以氢氧化钾为催化剂,在室温反应3h,得到了标题化合物,产率62%.     

植物生长调节剂菊乙胺酯的毒理试验

采用经口、经皮、眼刺激、皮肤试验方法,研究植物生长调节剂菊乙胺酯(WD-5)的毒性作用。结果表明,菊乙胺酯经口急性毒性LD50大于500 mg/kg,经皮急性毒性LD50大于2500 mg/kg,按农药急性毒性分级标准判定为低毒级化合物。对家兔皮肤无刺激性,对家兔眼睛在涂药后4 s冲洗的条件下呈现轻度刺激性。     

八乙酸蔗糖酯的合成工艺研究

以几种不同的碱性钠盐为催化剂对八乙酸蔗糖酯进行了合成，并研究了不同糖酐摩尔投料比、酯化温度、时间、催化剂用量及蔗糖粒度对产品收率的影响，得到了较佳合成工艺条件：n（糖）∶n（酐）为1.0∶10.5，酯化反应温度134℃，反应时间1h，催化剂用量2％，产率可达93.8%。采用了醇水重结晶的纯化分离方法，使产品质量得到进一步提高。产品经熔点和IR测试，证实了自制产品与美国产品的纯度基本一致。     

氢化葵花油脂肪酸蔗糖酯的合成

以氢化葵花油为原料 ,采用两步法合成了氢化葵花油脂肪酸蔗糖酯。探讨了反应温度、时间、压力、催化剂用量、助熔剂等对蔗糖酯收率的影响规律。结果表明 :当助熔剂和催化剂分别为 30 %和 2 .1%时 ,在 15 0℃下反应 6h ,产物收率达 4 5 %以上。     

乙苯,苯乙烯的生产及合成乙苯,苯乙烯催化剂的研究进展

苯乙烯是重要的石油化工原料。本文介绍了国内外苯乙烯生产的发展概况，合成乙苯，苯乙烯所用的催化剂种类，并就苯乙烯生产及催化剂的发展趋势提出了自己的观点。     

Synthesis and characterization of homopolymers and copolymers of various acrylates and acrylonitrile

Various homopolymers and copolymers of methyl acrylate, ethyl acrylate, butyl acrylate, and acrylonitrile in different feed ratios were synthesized. These were characterized by IR, ¹³C-NMR, DSC, DTA, and TGA. Spectroscopic characterization helped in differentiating copolymers of different mol ratios. Thermal analysis revealed different degradation patterns for homopolymers and copolymers. The temperature and energy changes associated with various phase transitions were dependent on the chemical composition of homo- and copolymers, as expected. © 1993 John Wiley & Sons, Inc.     

生物质气化及生物质与煤共气化技术的研发与应用

总结了生物质原料的特点及生物质单独气化的缺点;介绍了国内外生物质气化技术及生物质与煤共气化技术的研发与应用现状;分析了在此领域国内外的发展趋势与前景;概括了开展生物质与煤共气化技术研发的意义。     

Comparison of the Adhesion and Cohesion of Triblock and Random Copolymers of Styrene and Butadiene

A substantially greater detachment energy is required to strip a polyethylene tereph-thalate (Mylar) film from a styrene-butadiene-styrene (SBS) triblock copolymer compared to that for peeling from a random styrene-butadiene (SBR) copolymer. This is true even though the intrinsic interaction between the Mylar and each elastomer is expected to be similar because of their virtually identical chemical composition. It is proposed that this difference in peel strength (between the SBS and SBR) is a consequence of the much higher dissipative capacity of the former elastomer. Another manifestation of this is the higher cohesive tear strength of the SBS compared to the SBR. Extents of energy dissipation within each elastomer during detachment of the Mylar adherend are consistent with the hypothesis that the average maximum stress experience before detachment is some similar fraction of each elastomer's tensile strength.     

责任和责任心的涵义与结构

责任是人应主动承担的角色义务和对其因过失所造成后果应承担的责罚.有两层涵义:一是义务;二是后果.责任心是个体自觉做好分内事务和履行道德义务的心理倾向,是个性心理品质成分中自我特征维度上的重要内容.责任心具有两个方面的涵义:一是角色分内职责;二是角色道德义务.责任心是一种通过责任认知、责任个性和责任适应的动态形式表现出来的静态品质,责任心是责任心过程结构与责任心关系结构相互制约、相互影响的统一体.     

二甲基二烯丙基氯化铵和丙烯酰胺的合成及应用

用复合引发体系(过硫酸盐-偶氮类引发剂)和脂肪胺类氧化还原体系引发,在实验室获得了单体转化率≥98%,特性粘数高于13.6 dL/g的阳离子共聚物PDA,探讨了控制聚合物分子量的影响因素.     

钾盐资源及钾肥供需情况分析及预测

阐述了国内外钾盐资源及钾肥生产现状,对国内外钾盐的供需形势进行了分析及预测,从资源、原材料、国际市场三方面提出了解决我国钾盐短缺的措施。     

Electronic structures and reactivities of monometallic and bimetallic clusters of Au and Cu

The variation of the Au 4f binding energy of Au clusters with the cluster size has been established by measuring the binding energies of clusters whose size distributions were independently determined by HREM and STM. The binding energy increases significantly when the cluster size is less than 2 nm. Au-Cu bimetallic clusters of the composition Cu₃Au have been deposited for the first time on carbon substrates. The shifts in the core level binding energies of the bimetallic clusters show the effect of alloying in the case of large clusters, but show effects of both alloying and cluster size in the case of the small clusters. The interaction of CO with Cu₃Au clusters is stronger than with a bulk Cu metal. The interaction of CO with small Cu clusters also seems to be stronger than with bulk Cu or with large Cu clusters.     

Wetting properties of homopolymers and copolymers of pentafluorostyrene and methylacrylate and homopolymer blends

Polypentafluorostyrene (PPFS), polymethylacrylate (PMA), and poly(pentafluorostyrene-co-methylacrylate), poly(PFS-co-MA) were prepared and the wetting characteristics of polymer blends of PPFS and PMA were compared with that of poly(PFS-co-MA) via contact angle measurements. The critical surface tension of polypentafluorostyrene was found to be 22.6 dyne/cm, which is comparable to the value reported for polytrifluoroethylene (22 dyne/cm). The critical surface tension of poly(PFS-co-MA) is not linearly related to its composition. The polymer blends of PPFS and PMA exhibit significant surface enrichment of the fluoropolymer. The harmonic-mean method¹ was employed to determine surface tensions of these polymers and many known polymers. It is found that the method produces useful surface tension data provided the contact angle values are derived from testing liquids of dissimilar polarity.