纳米硫酸钡增强聚甲基丙烯酸甲酯复合材料实验探究

BaSO4纳米粒子/聚甲基丙烯酸甲酯(PMMA)复合材料的合成与表征的综合性实验,通过反相微乳液模板法合成复合材料,利用红外光谱、电镜、热重分析和差热分析方法表征了材料的性质。该复合材料制备方法简单,材料性能优异。综合运用了学生在基础化学实验阶段所学习的材料合成、仪器分析等基本技能,加深了学生对这些知识点的理解,使学生综合实验能力得到训练。     

Preparation and Storage of Silver Nanoparticles in Aqueons Polymers

以水溶性聚合物为保护剂,采用化学还原法制备了银纳米粒子,分别利用透射电子显微镜、紫外可见光谱、同步光散射光谱等手段对其进行了表征,并探索了制备银纳米粒子的最佳实验条件。通过将银纳米粒子-聚合物溶液进行脱水,得到含有银纳米粒子的固态聚合物膜。将固态聚合物膜重新溶解于水,其水溶液的紫外可见光谱与脱水前的溶液进行了比较,发现两者性质并无明显差异。因此,将银纳米粒子分散固定在聚合物膜中是一种崭新而有效的银纳米粒子制备和存储方法。     

银纳米粒子的绿色合成及其对荧光素室温磷光的增强效应

以β-环糊精(β-CD)作为稳定剂, 葡萄糖为还原剂, 银氨溶液为前驱体, 实现了绿色化学方法合成银纳米粒子. 利用紫外-可见分光光度法(UV-Vis)、高分辨透射电镜(HRTEM)、红外光谱法(FTIR)对产物进行了表征. 将银纳米粒子引入滤纸表面增强室温磷光(RTP)的研究, 发现银纳米粒子对醋酸铅诱导荧光素(FL)所得的RTP具有明显的增强效应, 并且随着银纳米粒子加入量的增加具有先增强后猝灭的趋势. 对β-CD与银纳米粒子的相互作用机理及银纳米粒子对FL RTP增强效应的作用机理进行了初步讨论.     

科研转化的综合化学实验:银纳米粒子的制备及其催化反应动力学测量

设计了一个包含胶体化学方法制备金属纳米粒子及其作为异相催化剂催化氧化还原反应的动力学过程等内容的本科生综合化学实验。首先采用晶种生长法合成了不同尺寸的球状和片状银纳米粒子,然后经过离心纯化后作为异相催化剂催化硼氢化钠还原4-硝基苯酚的反应,研究了催化反应动力学过程,分析了催化反应的表观反应速率常数和催化剂的活性。本实验可以锻炼学生制备纳米材料和跟踪反应动力学进程的能力,使学生进一步理解异相催化反应机理、熟悉光谱仪器的应用。     

多酸配位聚合物的制备与表征——推荐一个综合化学实验

介绍了一个综合化学新实验--多酸配位聚合物的制备与表征。通过杂多酸和有机配体的合成、多酸配位聚合物的制备和性能表征,使学生了解多酸配位聚合物这一无机合成化学前沿领域,在引导学生进行材料合成及性质表征的过程中,提高学生对已学知识融会贯通的能力,提升学生学习化学的兴趣。本实验综合了无机、有机化学知识点以及实验、仪器操作和数据分析能力的培养,可纳入高年级综合化学实验。     

CdS纳米粒子与半胱氨酸相互作用的研究

合成了粒径均匀和分散性好的CdS纳米粒子.通过改变CdS纳米粒子及半胱氨酸的浓度、体系的pH值及CdCl2和CH3CSNH2摩尔比等实验条件跟踪监测了CdS纳米粒子光谱性质的变化,探讨了CdS纳米粒子与半胱氨酸之间的相互作用及化学反应机理.     

银纳米粒子与氧化物纳米异质结构制备及应用

总结了近期银纳米粒子与氧化物纳米异质结构制备及应用研究进展情况,特别是银纳米粒子修饰的氧化钼纳米纤维异质结构、银纳米粒子修饰的钛酸盐纳米纤维异质结构、银纳米粒子@二氧化硅@银纳米粒子三明治异质结构的制备方法与性能表征.介绍了以上三种异质纳米复合结构的催化性能和银纳米粒子修饰的二氧化物纳米纤维异质结构的气体传感性能.     

综合化学实验:铽(Ⅲ)发光配合物的合成、结构与性质

介绍了一个综合化学实验,涉及配体的合成和铽（Ⅲ）配合物的合成、结构以及荧光性质的表征。该实验将大学阶段的基础知识、基本实验技能与学术研究的前沿相结合。在实验教学中融入了配位化学和稀土配合物的知识,能够引导学生深入理解配位化学相关概念及理论,并初步了解稀土配合物发光性质与中心离子轨道能级间的关系,同时熟悉大型仪器,培养学生理论联系实际的能力以及综合实验技能。     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

     

Synthesis of phenolic components of Grains of Paradise

Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.     

Summary of development of the theory of stability of colloids and thin films

In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.     

Study of hydration of two cements of different strengths

Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M_o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700^oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.     

氯氧化镁生成热的研究

用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。     

Thermodynamics of the formation of oxosulfides of rare-earth elements

The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.     

探究“铁的锈蚀条件”实验创新设计

设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。