南瓜籽烘烤前后化学成分的分析

对烘烤前后南瓜籽中的化学成分进行分析并对比。采用同时蒸馏萃取装置萃取南瓜籽中的挥发性成分,采取超临界CO2萃取技术萃取南瓜籽油脂,并将其分为酸、碱、中性三个部分,用气相色谱-质谱联用方法分析其中化学成分并进行对比。结果表明,南瓜籽挥发性成分中含有多种醛类和酯类化合物,烘烤后产生了大量的烷基吡嗪,其在碱性部分中的相对含量比烘烤前提高14倍多,不饱和醛类化合物含量也有明显提高。南瓜籽油脂中的主要化学成分是油酸、亚油酸及其酯类。还含有生物活性功能成分如植物甾醇、角鲨烯和维生素E等。烘烤后除角鲨烯含量有所降低,维生素E、植物甾醇、亚麻酸等均有提高。     

CH自由基和NO~2反应研究: I. 反应的热力学计算

探讨了CH自由基与NO~2反应的可能路径,通过计算确定了反应物,产物和稳定中间体的电子状态和平衡构型,并运用Gaussian-3方法和MRCISD方法对可能的反应路径进行了热力学计算。在多数情况下与实验值符合较好。对于个别与理论计算差别较大的实验值进行了评述。     

二氧化钛纳米微粒膜光电化学行为的研究

利用不同的制备方法制备出二氧化钛纳米微粒膜，对二氧化钛纳米微粒膜的光电化学材为和产生的机理进行了研究．结果表明；二氧化钛纳米微粒膜除了具有传统半导体的光电化学性质外，还具有不同于传统半导体的光电化学性质这主要是出膜的微粒性引起的，可综合传统半导体和胶粒半导体两种模型来加以解释。     

分散液液微萃取/气相色谱-质谱法测定蜂蜜中六六六和滴滴涕类农药残留

建立了分散液液微萃取(DLLME)与气相色谱-质谱法(GC-MS)联用快速检测蜂蜜中六六六(BHC)和滴滴涕(DDT)类农药残留的分析方法.使用三氯甲烷为萃取剂,通过涡旋、离心使分析物富集到微量三氯甲烷中,采用气相色谱-质谱进行分析.实验对影响DLLME萃取效率的因素,如萃取剂种类和体积、分散剂种类和体积、萃取时间等进行了考察,同时对方法的基质效应和性能进行了评估.结果显示:由于基质效应,8种六六六和滴滴涕类农药都出现信号增强现象.8种六六六和滴滴涕类农药在2~500 μg/L范围内线性关系良好,相关系数(r²)为0.991~0.998,方法富集倍数为74~96;当试样的加标水平为20、50和100 μg/kg时,8种六六六和滴滴涕类农药的回收率为61.0%~100.1%,相对标准偏差(RSD, n=5)为2.2%~19.5%.8种六六六和滴滴涕类农药的最低检测浓度均为20 μg/kg,最小检出量皆为1.0 ng.该方法简单、快速、高效,适用于蜂蜜中六六六和滴滴涕类农药的残留检测.     

Synthesis,characterization, and antimicrobial activity of some novel poly(ether ketone)s

Low molecular weight poly(ether ketone)s were synthesized from phenol, 1,4‐phenylenedioxy diacetylchloride, chloroacetylchloride, and dichloroalkanes [1,2‐dichloroethane and dichloromethane] by a Friedel–Crafts reaction with anhydrous aluminum chloride as a catalyst and carbon disulfide as a solvent. The conditions for the preparation of the poly(ether ketone)s and the chlorine contents obtained with the Carius method were examined, and a reaction scheme for each resin was established. The molecular weights and polydispersities of the resins were obtained by gel permeation chromatography. The polyketones were characterized by IR spectroscopy. The characteristic frequencies due to different functional groups were assigned. The thermal properties of the resins were studied with thermogravimetry and differential scanning calorimetry. The characteristic temperatures of thermal degradation for the poly(ether ketone)s were evaluated with thermogravimetric analysis. The kinetic parameters for the decomposition reactions of the resins were obtained with Broido and Doyle's method, and the heats of fusion were obtained from differential scanning calorimetry thermograms. The polyketones were thermally stable up to 200 °C. All the polyketones were tested for their microbial properties against bacteria, fungi, and yeast. The effect of poly(ether ketone)s on the growth of these microorganisms was investigated, and the polyketones were found to inhibit the growth of the microorganisms to a considerable extent. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2335–2344, 2003     

气相色谱-质谱联用法测定橡胶制品中多环芳烃（蒽）含量不确定度评定

目的对气相色谱-质谱联用仪法测定橡胶制品中多环芳烃（蒽）含量不确定度进行评定,确定影响不确定度的关键因素。方法依据《ZEK01.4-2008 GS认证过程中PAHs的测试和验证》,使用气相色谱-质谱联用仪法测定橡胶制品中多环芳烃（蒽）含量,并对结果的不确定度进行评定,分析影响测量不确定度的各个因素,对各个分量进行计算和合成。结果扩展不确定度U=5.7 mg/kg,置信概率95%。结论该实验的不确定度主要影响因素是曲线校准。     

ADSORPTION OF PHENOL AND NITROPHENOLS ON A HYPERCROSSLINKED POLYMERIC ADSORBENT

The adsorption of phenol and nitrophenols on hypercrosslinked polymeric adsorbent wasstudied as a function of the solution concentration and temperature. Adsorption isotherms of phenoland nitrophenols on hypercrosslinked resin were determined. These isotherms were modeledaccording to the Freundlich adsorption isotherm. The isotherms for phenol and nitrophenols onhypercrosslinked resin were assigned as L curves. Thermodynamic parameters were calculated for allphenol and nitrophenols. The kinetics experiment results showed that the adsorption rates were of thefirst-order kinetics. The rate constants at 303K were calculated.     

Copper(II) complexation with 1-methyl-2-mercaptoimidazole in 7 M HCl

The complexation of copper(II) with 1-methyl-2-mercaptoimidazole in 7 M HCl was potentiometrically studied. The compositions of complexes were determined, and their stepwise formation constants were calculated. The complexes were shown to become less stable with increasing temperature. The thermodynamic functions of complexation were estimated. The copper complexes were shown to surpass the rhenium complexes in stability.     

废弃油脂生产生物柴油的研究进展

简单介绍了生物柴油的生产原料,综述了用废弃油脂生产生物柴油的现状和方法。废弃油脂生产生物柴油的方法主要有物理法和化学法,物理法主要有掺和法和微乳法,化学法主要有热裂解法和酯交换法。目前生产中采用化学法的酯交换法、以酸碱两步催化法的工艺为主,而生物酶法和超临界法是研究热点。     

Synthesis,Luminescence and Intramolecular Energy Transfer of Binary and Ternary Rare Earth Complexes with Aromatic Carboxylic Acids and 1, 10-Phenanthroline

A series of binary and ternary rare earth complexes with para-substitued benzoic acids and 1,10-phenanthroline were synthesized. The phosphorescence spectra were measured and the lowest triplet state energies of ligands were determined, the phosphorescence lifetimes were obtained and intramolecular energy transfer mechanism between ligands was studied. The luminescence properties were also measured and were in agreement with the prediction. The energy match and intramolecular energy transfer process in these binary and ternary complexes were discussed in detail.     

Theoretical Studies on Electronic Structures and NMR Spectra of Oligo(4‐vinylpyridine)

Poly(4‐vinylpyridine) was determined to possess conductivity in the experiment. In order to understand properties of the polymer, a series of 4‐vinylpyridine oligomers were designed. The structures of these oligomers were optimized using density function theory (DFT) at B3LYP/6‐31G(d) level. The energy gaps and thermal stabilities of the oligomers were decreased when the chain lengths were increased. These properties were also decreased owing to the protonation of the pyridine ring. The holes were easily injected into the oligomers in the presence of hydrochloride. The electrons were conducted in the side chain composed of the pyridine rings rather than the main chain owing to the saturation of the main chain. The ¹³C nuclear magnetic resonance (NMR) spectra and nucleus independent chemical shifts (NICS) of these compounds were calculated at B3LYP/6‐31G(d) level. The chemical shifts of the carbon atoms connected with the nitrogen atoms in the protonated pyridines were moved upfield in comparison with those of the pyridines. The addition of hydrochloride on the pyridine ring in the oligomers led to the increase of the aromaticities, namely the aromaticities of the oligomers were obviously improved when the pyridine rings were protonated.     

Fragmentation of valine and proline in resonant free electron capture reactions

The processes of resonant electron capture by molecules of valine and proline were studied. The main dissociative decay channels of molecular ions and the structures of fragment ions were established. The reactions of simple bond cleavage and H-shift rearrangement processes were revealed. The dissociative electron attachment cross-sections for [M - H]^? ions were measured in the region of 1.25 eV. The metastable decay of [M - H]^? ions were found in the energy region of 4.5?C8 eV. The structures of decomposing parent ions were determined using the statistical model of metastable fragmentation.     

含碲唑杂环部花青的性能研究

本文报道了由新型杂环苯并碲唑衍生的4个染料中间体以及三种类型共6个部花青。染料合成的条件依酸性酮亚甲基核而异。研究了染料吸收光谱的溶剂效应, 发现极性较弱的罗丹宁部花青随着溶剂极性增大呈现吸收峰的显著红移, 而极性较强的双甲酮及巴比妥酸部花青的吸收则显示一定程度的蓝移。利用共振理论解释了上述现象。同时发现具有相似溶剂效应的两种部花青的转移能量(E~T)图呈现很好的线性关系, 有可能用作溶剂极性的指示剂。     

ADSORPTION OF PHENOL AND NITROPHENOLS ON A HYPERCROSSLINKED POLYMERIC ADSORBENT

1. INTRODUCTION Nitrophenols are versatile raw materials in chemical industry and used in a great diversity of applications such as herbicides, insecticides and bactericides. Due to their extreme toxicity and adverse effect upon human and biota at very l…     

MALDI-TOF质谱准内标法及其用于rhTPO复杂糖一致性研究

采用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)准内标法准确测定重组人血小板生成素(rhTPO)仿制药和原研药中4类糖修饰的相对含量,并进行样本间和批间一致性比较。结合多种切糖酶逐步切除rhTPO的N-糖、唾液酸和O-糖;以牛血清白蛋白(BSA)为标准品,与样本非混合点靶;采用MALDI-TOF质谱准内标法检测,分别获得各样本完整含糖分子量及不同层次切糖后分子量;通过分子量差值计算4类糖修饰的相对含量;最后比较仿制药与原研药样本间和批间一致性。以BSA多电荷峰对rhTPO切糖前后的MALDI-TOF质谱测定值进行准内标法校正,BSA多电荷峰之间相对标准偏差(RSD)均≤0.075%,批间RSD为0.001%~0.004%,方法误差均0.01%。rhTPO仿制药N-糖、O-糖唾液酸、O-糖和糖化糖的相对含量分别约为24.6%、2.9%、9.0%和5.1%,批间一致性良好,且总糖含量与文献值一致;rhTPO原研药N-糖、O-糖唾液酸、O-糖和糖化糖的相对含量分别约为25.6%、2.9%、7.9%和3.5%,总糖含量较文献值偏低。与rhTPO原研药相比,仿制药糖基化糖相对含量基本一致,糖化糖含量有差异。rhTPO糖化糖研究未见文献报道,其差异是不同厂家rhTPO之间差异的重要因素,主要由发酵工艺差异导致。     

Determination of the additive physical properties of the components of complex mixtures

Summary The density, refractive index and absorptivities at chosen wave numbers were determined for all the components of three-component mixtures. The mixtures were treated of three-component mixtures. The mixtures were treated as being of unknown qualitative and quantitative composition. The quantitative gas chromatographic analysis by means of the method of linear relationship was carried out and the values of the physical properties of complex mixtures were measured. The corresponding properties of acetone, benzene and toluene were evaluated from the set of appropriate equations.     

顶空-气相色谱-飞行时间质谱鉴定分析饮用水中的异味成分

使用顶空-气相色谱-飞行时间质谱结合差异化分析软件鉴定分析出了饮用水中的异味物质。质谱数据通过逐级筛查，降低化合物数量，通过T检验和倍数变化统计分析查找差异显著的化合物，利用结构解析确定异味成分为乙醛。通过正交试验优化了加热时间、加热温度、样品量和加盐量等因素。检出限和定量限分别为0.0033和0.010 mg/L，线性范围为0.010~0.500 mg/L，相关系数R²=0.997。对实际样品进行了检测，分析了产生异味的原因，并对相应的生产加工工艺提出了合理化建议。该方法简便、快速、灵敏，适用于鉴定分析饮用水中的异味成分。     

乳状液膜法分离水中汞的研究

报道了用乳状液膜法分离汞的研究。确定了最佳分离条件；流动载体TBP（磷酸三丁酯）和表面活性剂Span80的浓度均9％，内相溶液NaOH和外相溶液HCl的浓度分别为0.4mol/L和0.02mol/L，制乳时间和混合时间分别为10min和5min，乳水比和油内比分别为0．5和0．8。     

积雪草中五种微量元素的形态分析

按照传统煎煮法对积雪草中铁、锰、锌、铜和锶5种元素进行提取,用微孔滤膜分离提取液中的可溶态与悬浮态,利用阳离子交换树脂柱、大孔吸附树脂柱和螯合树脂柱对可溶态中的游离态和非游离态、有机态和无机态、稳定态和不稳定态进行分离后,采用火焰原子吸收光谱法(FAAS)对各种形态中的上述5种元素进行测定。结果显示,积雪草中5种元素的提取率为11.88%～22.86%,浸留比为14.04%～31.44%。该法测定各元素的回收率为95.6%～104.3%,相对标准偏差在0.37%～1.14%之间,具有较好的精密度和准确度。     

Theoretical comparison of molecular properties of linear and cyclic glycine derived peptides and their phosphor analogues

The cyclic compounds are common in nature and widely spread in medicinal chemistry. The cyclopeptides have a special position for their having numerous advantages over their linear, parent peptides. Here, cyclic glycine derived peptides and their linear equivalents were computationally modelled and the molecular properties of both these groups of the compounds were compared. The phosphor analogues of these peptides were also modelled and the same properties were considered. The studies were done by the ab initio methods. The stability and strength of peptide bonds were calculated and the susceptibility of studied compounds to spontaneous oxidation was estimated.