天然和人工培植红景天挥发油的对比研究

应用ＧＣ－ＭＳ和ＧＣ－ＩＲ两种联机法对比研究了天然和人工培植红景天挥发油、分别鉴定出２７个和２４个化合物。ＭＳ给出结构信息和ＩＲ给出官能团信息相结合，提高了分析测试复杂样品的可靠性。     

中药党参挥发性成分分析

采用“乙醚冷浸－索氏提取－水蒸汽蒸馏”方法对党参中挥发性成分进行提取,用ＧＣ分离,加标定性和ＧＣ－ＭＳ联用鉴定其组分。分离出２６８种化合物,鉴定出６４种。     

生姜挥发油的提取及其化学成分的气相色谱—质谱分析

本文对生姜挥发油的提取先采用水蒸气蒸馏法，然后对馏出液用乙醚萃取，得到提取物Ｉ，经ＧＣ／ＭＳ检测出４０种化合物，对乙醚萃取后的馏出液选用乙酸乙醋进一步提取，用ＧＣ／ＭＳ检测还鉴定出２８种化合物，提取出的挥发油重量占总油量３９％．     

用GC—MS法测定尿中可待因及其代谢物的浓度

建立了用ＧＣ－ＭＳ（ＳＩＭ）内标定量法快速测定人尿中可待因及其代谢物浓度的方法，样品经酸水解、乙醚／异丙醇提取，用ＭＳＴＦＡ－ＭＢＴＦＡ衍生化后进样于ＧＣ－ＭＳＤ，方法灵敏、准确，可用于监测吸毒者尿中可待因，吗啡类药物的浓度。本法已经受ＩＯＣ的１９９２年水平考试的考验。     

溶剂抽提、水蒸气蒸馏和超临界萃取用于古蓬香脂组成分析方法的比较(英文)

采用乙醇和丙酮溶剂抽提、ＣＯ２超临界萃取（ＳＦＥ）以及水蒸气蒸馏（ＳＤ）的方法提取古蓬香脂乳胶。对乙醇和丙酮提取物进行了ＨＰＬＣ和ＧＣ－ＭＳ分析。两个提取物的ＨＰＬＣ谱图十分相似,总共可分离出１７个组分。而乙醇提取物的ＧＣ－ＭＳ分析鉴定表明有２１个组分。ＳＦＥ提取物的ＧＣ－ＭＳ分析得到８个组分。ＳＤ提取物有１４个组分。在超临界流体中加入甲醇无论对提取物的组分数还是对其浓度都没有什么影响。     

用GC－MS法测定尿中可待因及其代谢物的浓度

建立了用ＧＣ－ＭＳ（ＳＩＭ）内标定量法快速测定人尿中可待因及其代谢物浓度的方法。样品经酸水解、乙醚／异丙醇提取，用ＭＳＴＦＡ－ＭＢＴＦＡ衍生化后进样于ＧＣ－ＭＳＤ，方法灵敏、准确，可用于监测吸毒者尿中可待因、吗啡类药物的浓度。本法已经受ＩＯＣ的１９９２年水平考试的考验。     

头发中单乙酰吗啡和吗啡检测的研究

建立了用ＧＣ－ＭＳ技术检测人头发中毒品海洛因的主要代谢产物６－单乙酰吗啡和吗啡的方法。以乙基吗啡为内标，样品酸水解后用混合有机溶剂提取。提取物经Ｎ－甲基－Ｎ－三甲基硅基三氟乙酰胺（ＭＳＴＦＡ）衍生化，采用ＧＣ－ＭＳ定性定量分析。该法已用于确认经常性滥用海洛因的实际检案分析     

GC／MS检测信息的综合利用

从充分利用气相色谱／质谱（ＧＣ／ＭＳ）提供的信息来鉴定ＧＣ流出组分的目的出发，并以脂肪醇分析为例讨论了ＧＣ保留指数在ＭＳ谱图解析及ＭＳ鉴定结果的合理性检验方面的作用。总结了ＧＣ保留的同系物规律、极性规律、加和规律及异构物规律来指导ＭＳ谱图解析。提出了含氧化合物官能团相对于－ＣＨ２－质量数的保留指数附加贡献值辅助ＭＳ确定化合物的类别。同时采用了ＧＣ／ＭＳ中选择离子检测方法（ＳＩＭ）在分子离子峰受噪音干扰或太弱以至完全未观测到时来进一步佐证其相对分子质量。     

γ－环糊精－SDS胶束电动色谱法分离十八甲基炔诺酮光学异构体

研究了ＣＤ－ＳＤＳ胶束电动色谱（ＣＤ－ＭＥＫＣ）对电中性及疏水性的手性化合物的分离，并讨论了不同类型ＣＤ的手性识别作用。使用γ－ＣＤ可以有效地拆分十八甲基块诺酮（ＮＯＧ）旋光异构体。选择了最佳分离条件，通过调节ＣＤ和ＳＤＳ浓度以及其它操作条件可以把ＮＯＧ异构体很好的分离。     

γ－环糊精－SDS胶束电动色谱法分离十八甲基炔诺酮光学异构体

 研究了ＣＤ－ＳＤＳ胶束电动色谱（ＣＤ－ＭＥＫＣ）对电中性及疏水性的手性化合物的分离，并讨论了不同类型ＣＤ的手性识别作用。使用γ－ＣＤ可以有效地拆分十八甲基块诺酮（ＮＯＧ）旋光异构体。选择了最佳分离条件，通过调节ＣＤ和ＳＤＳ浓度以及其它操作条件可以把ＮＯＧ异构体很好的分离。     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

A NOVEL APPROACH TO RHEOLOGICAL CHARACTERIZATION FOR THE GELATION IN POLYMER CRYSTALLIZATION

The isothermal crystallizations of three kinds of commercial isotactic polypropylene have been studied by DSC and rheometric experiments, in a range of temperatures where the rate of crystallization is moderate. As the crystallization proceeds, volume contraction induces tensile force upon the parallel plates. The tensile force relaxed quickly in liquid states,but after a critical amount of the relative crystallinity, it starts to accumulate in the static test, that is, with the motionless parallel plates. A new method to determine the liquid-solid transition by the static tensile force is proposed and compared with two dynamic methods of detecting liquid-solid transition, that is, the power-law modulus theory and the yield modulus model. The tensile force method predicted considerably earlier transition than the dynamic methods, and the corresponding DSC data indicate relative crystallinity of larger than 0.2 at the transition times. The limitation of dynamic methods and other possible errors have been analyzed. While the dynamic methods are suitable for slow crystallization, the tensile force method is more appropriate for the crystallization of moderate rates. Moreover, it has the advantage of almost not disturbing the crystallizing materials before the transition.     

分子线电子输运特性的第一性原理研究

从第一性原理出发,利用密度泛函理论研究了SH-C8H16-SH分子和金表面的相互作用,并利用分子前线轨道理论和微扰理论定量地确定了该相互作用能常数,然后,利用弹性散射格林函数方法研究了该分子与金表面形成的分子线的伏-安特性.研究结果表明,当含有硫氢官能团的有机分子化学吸附于金表面时,硫原子将与金原子形成以共价键为主的混和键,此时,扩展的分子轨道使分子线的电导呈现出欧姆特性,而对于局域的分子轨道,电子的输运只能通过隧道效应来实现.对分子线伏-安特性的计算结果显示,在零偏压附近,存在一个电流禁区,随着偏压的增加,分子线的电导呈现出平台特征.     

Thermoelectric Properties of Czochralski GeSi Crystal

In order to discuss the application possibility of SiGe crystal in thermoelectric materials,we investigated the thermoelectric properties of several silicon-germanium alloys with different content,orientation and electric conductive type. As discussed in the experiment result,the absolute value of Seebeck coefficient fluctuates from 300 to 600 μV/K in the whole temperature range. In the present paper,the relationship of Seebeck coefficient against content,orientation and electric conductive type is summarized in detail. The Seebeck coefficient of the sample with <111> orientation is smaller than that in <100> at the same temperature. Absolute value of P-type is larger than that of N-type except pure Ge. But as the temperature increases,the absolute value of pure Ge decreases many times as quickly as that of other specimens. In addition,the specimens of bulk GeSi alloy crystals for experiment were grown by the Czochralski method through varying the pulling rate during the growing process.     

PHONONS IN POLYACENIC CHAINS

We have theoretically resolved phonon excitations in quasi-two-dimensional organic crystals of polyacenic semiconductor material which may be obtained by the pyrolytic treatment of phenol-formaldehyde resin. A model for studying the dynamical properties using three polyacene chains is proposed with the aim to present the vibrational properties of this structure. It employs the formalism of solid states in two dimensions which admit phonons. A simulation process of the two-dimensional lattice structure shows that elastic waves may explain the existence of vibrational modes in the frequency range 100-400 cm-1. The presence of acoustic and optical like phonons is discussed in terms of the elastic force constants. A hyperfine resonance structure is obtained. It allows the analysis of the dynamical evolution in thin films of polyacene. It is found that the behavior of the phonon density of states exhibits resonance between modes in the structure.     

SYNTHESIS OF POLY（3,4-AZOPYRIDYLENE） AND OXYGEN-BINDING AFFINITY OF ITS COMPLEX WITH COBALTPORPHYRIN

Synthesis and characteristics of poly(3,4-azopyridylene) (PAP), conductivity and oxygen-binding affinity of its complex with meso-α,α,α,α-tetrakis(o-pivalamidophenyl) porphyrinatocobalt(Ⅱ) (CoP) were studied. PAP was prepared by oxidative polymerization of 3,4-diaminopyridine (DAP) in DMF solution using CuCl/pyridine as the catalyst. IR and NMR results showed that the peak of amido group in DAP was converted to the azo group in PAP and a π conjugated polymer was synthesized. The average molecular weight of PAP was determined to be 5.0 × 103. The PAP-CoP complex was prepared by complexing the pyridyl group of PAP with the fifth coordination site of CoP in DMF solution. In comparison with the CoP complex with a non-π conjugated polymer, the PAP-CoP complex shows good electroconductivity of 5.8 × 10-6 Scm-1. The PAP-CoP complex displays a reversible change in the UV-Visible absorption spectrum from the deoxy form to the oxy or oxygen-binding one with an isosbestic point, in response to the partial oxygen pressure of the atmosphere. The oxygen-response behavior was monitored at the absorbance ascribed to the oxy form at 548 nm to give the oxygen-binding affinity.The oxygen-binding equilibrium curves of PAP-CoP complex obey a Langmuir isotherm. DMF has great effects on the oxygen-binding properties of the PAP-CoP complex. The oxygen-binding affinity of PAP-CoP complex in the solid state is higher than that in DMF solution. With decreasing temperature, the oxygen-binding affinity of the PAP-CoP complex increases.     

液晶聚合物/柔性链聚合物共混体系相分离形态

利用元胞动力学方法在二维情况下对浓度、取向序参量的含时Ginzberg-Landau方程进行数值求解,研究了液晶聚合物/柔性链聚合物共混体系的相分离动力学,考察了浓度、取向有序过程的耦合对相分离形态的影响.结果表明,此耦合作用对相分离的时间进程以及相分离图样的空间排布都有影响.液晶聚合物的取向有序相当于增加了两组分间的不相容性而促进两相分离;两个序参量在热力学方面的耦合使液晶聚合物趋向于沿着界面方向取向,而动力学方面的耦合使液晶聚合物分子沿着其取向方向扩散,相分离图样的空间排布由这两种效应共同决定通过极化率张量的定义用数值方法模拟得到了相分离体系的小角光散射图样,结果表明,散射强度分布具有方位角依赖性,它是由浓度、取向序参量的空间变化共同决定的.     

PROPERTIES AND MORPHOLOGY OF UNSATURATED POLYESTER/ACRYLATE-TERMINATED POLYURETHANE/ORGANOMONTMORILLONITE NANOCOMPOSITES

Unsaturated polyester resin （UPR）/acrylate-terminated polyurethane （ATPU）/organo-modified montmorillonite （OMMT） nanocomposites were prepared by the in situ intercalative polymerization method. Samples were prepared by the sequential mixing, i.e. mixture of the ATPU and styrene （S） and OMMT were prepared in the first step; UPR was then added to the pre-intercalates of ATPU/S/OMMT. Results indicate that the mechanical properties and thermal properties of UPR/ATPU/OMMT nanocomposites greatly depend on the amount of ATPU and OMMT. Results show that the addition of ATPU could increase the impact strength of UPR/ATPU composites, but the tensile strength, flexural strength and heat resistance of the materials are obviously decreased. When the weight ratio between UPR, ATPU and OMMT were 82：15：3, the impact strength and heat distortion-temperature of nanocomposite were greatly improved, meanwhile there was little change for other properties of the nanocomposites. The synergistic enhancement effects of ATPU and OMMT on the composites were observed. The structures and morphology of the composites were investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy.     

DFT Studies on Non-IPR C_(68) and Endohedral Fullerene Sc_3N@C_(68)

The structures and spectra of 20 possible isomers of C78(CH2)3 have been studied by using AM1,INDO/CIS and DFT methods. The results show that the most stable isomer is 1,2,3,4,5,6-C78(CH2)3 (A) with annulene structures,where three -CH2 groups are added to the 6/6 bonds located at the same hexagon passed by the shortest axis of C78 (C2v). Compared with that of C78 (C2v),the first absorption in the electronic spectrum of C78(CH2)3 (A) is blue-shifted because of its wider LUMO-HOMO energy gap. While the IR frequencies of the C–C bonds on the carbon cage are red-shifted owing to the formation of annulene structures and the extension of the conjugated system. The chemical shifts of the carbon atoms in 13C NMR spectra are moved upfield upon the addition.     

Dilatometric study of glass transition kinetics in polyisoprene

From dielectric measurements the thermal dependence and the distribution function of the relaxation times can be determined. In the present contribution we are testing the correspondence between the relaxation times obtained from the dielectric measurement and the dilatometric behavior of the material in the vicinity of the glass transition temperature. The experimental data used for the comparison were obtained for the sample of polyisoprene.