脊髓小脑变性疾病病人血清铜,锌,铝,铁含量的研究

脊髓小脑变性疾病（ＳＣＤ）的病因可能与遗传、神经生化紊乱、感染、微量元素平衡障碍及自由基损伤等因素有关，其中微量元素平衡障碍的研究具有重要意义。检测了ＳＣＤ中发病率较高的橄榄桥小脑萎缩症（ＯＰＣＡ）及晚发性小脑皮质萎缩症（ＬＣＣＡ）病人１５例血清中铜、锌、铝、铁等微量元素含量。发现病人比对照组铜明显降低，Ｐ〈０．０１；锌明显降低，Ｐ〈０．０１；铝明显升高，Ｐ〈０．０１；铁无明显差别。     

Thermal Emulsion Polymerization without any Conventional Initiators and Emulsifiers

Stable poly(styrene-co-sodium styrene sulfonate) (P(St-NaSS) nanoparticles with broader size distribution were synthesized by thermal emulsion polymerization without any conventional initiators and emulsifiers. The obtained polymer nanoparticles have higher ξ potential, and the particle sizes have broad distribution. The stability of polymer particles originated from the addition of small amounts of ionic comonomer, NaSS, which can act as an emulsifier in somewhat. The monomer conversion could reach up to about 28 wt% in 48 h, and did not increase by further polymerization when higher polymerization temperature (120 ℃) was employed. This polymerization system may be give some further understand for mechanism of emulsion polymerization.     

Cooperation of reducing species for NO reduction over Ag/Al2O3 under oxidizing conditions

Summary The cooperation effect of reducing species for selective reduction of NO over Ag/Al₂O₃ has been investigated in the presence of excess oxygen. When the combinations of propene or propane and ethanol or methanol were used as reducing agents, NO reduction took place over a wider temperature range, compared with a single hydrocarbon as reducing agent.     

合成气制乙醇的铑基催化剂中助剂铁,锂的作用本质研究

催化活性测试表明,助剂Fe具有显著提高乙醇生成选择性及铑催化活性的双重作用;助剂Li具有显著提高乙醇选择性的作用,对铑催化活性影响不大。基于H_2/D_2同位素效应结果及CO化学吸附、IR、XRD、XPS等的表征结果,认为助剂Fe经活化处理后大部分与Rh形成RhFe合金,使Rh分散度显著提高,从而提高了乙醇的选择性;Rh分散度的提高以及小部分以Fe~(2+)(Fe~(3+))形式存在的助剂Fe促进甲酰基的生成及随后的氢解断C-O键反应是助剂Fe促使铑催化活性提高的两个因素。Li的主要作用在于通过与C_2含氧中间体乙烯酮氧端的弱亲合作用,促进了乙醇前驱体的生成,从而使乙醇生成选择性提高。     

The vibration-rotation emission spectrum of gaseous HZnCl

Gaseous HZnCl has been synthesized for the first time in a high-temperature tube furnace with a dc discharge in a flowing mixture of pure HCl and Zn vapor. The vibration-rotation emission spectrum of HZnCl was recorded at high resolution using a Fourier transform spectrometer. The H-Zn stretching modes (nu(1)) of the H(64)Zn(35)Cl, H(66)Zn(35)Cl, H(68)Zn(35)Cl, and H(64)Zn(37)Cl species, as well as the 2nu(1)-nu(1) hot band of the most abundant isotopologue H(64)Zn(35)Cl, were observed near 1966 cm(-1). A least-squares fit was performed for each of the four observed isotopologues, and their spectroscopic constants were determined.     

Determination and Differentiation of Two Seemingly Identical Medicinal Herbs by Capillary Electrophoresis with Electrochemical Detection

A high-performance capillary electrophoresis with electrochemical detection (CE-ED) method has been employed for the determination of six bioactive ingredients in traditional Chinese herbs, Herba cepbalanoplosis segeti and Herba cirsii japonici. The effects of several factors such as the acidity and concentration of running buffer, the separation voltage, the applied potential and the injection time on CE-ED were investigated. Under the optimum conditions, the six analytes could be well separated within 21 min in a 75 cm length capillary at the separation voltage of 15 kV in a 50 mmol L^–1 borax running buffer (pH 8.4). A 300 m diameter carbon disk electrode was used as the working electrode positioned carefully opposite the outlet of the capillary in a wall-jet configuration at potential of +950 mV (vs. SCE). Good linear relationship was established between peak current and concentration of analytes over two orders of magnitude with detection limits (S/N=3) ranged from 1.5×10^–7 to 6.0×10^–7 g mL^–1 for all six analytes. This proposed method has been successfully applied for the analysis of traditional Chinese herbs after a relatively simple extraction procedure, further on, for the differentiation of these above two seemingly identical herbs based on their electropherograms or characteristic electrochemical profiles.     

A new insight into the adsorption of bovine serum albumin onto porous polyethylene membrane by zeta potential measurements, FTIR analyses, and AFM observations

The mode of adsorption of bovine serum albumin (BSA) on porous polyethylene (PE) membrane was studied as a function of time and concentration, which may contribute to the surface coverage. An improved physical model for adsorption is initiated based on the results of the adsorptional and desorptional measurements, FTIR analysis, and AFM observations as well as streaming potential measurements. The results obtained indicate that the adsorptional mode depend on both time and concentration. It is shown that a critical concentration (about 1000 ppm here) exists in the adsorptional process. Below this concentration, the adsorption seems to be conducted in a normal side-on way but time elapse gives rise to greater conformational change than concentration increase; above this concentration, the aggregation of protein molecular plays a decisive role and the adsorption is in an aggregation way, which is similar to end-on, but a relative large gap between the adsorbed molecules exists due to aggregation. This conclusion is general and can be expected to apply in other globular protein-hydrophobic porous surface systems.     

Interesting fluorescence properties of C60-centered dendritic adduct with twelve symmetrically attached pyrenes

A C60-centered dendritic adduct with 12 symmetrically attached pyrene species was synthesized and found to have relatively simple fluorescence emission kinetics, in particular, the mono-exponential decay of the significant pyrene excimer emission.     

K-Mo基催化剂的表面酸性与其合成醇选择性

对500℃和800℃焙烧制得的氧化态K－MoO3／γ－AlO3，K－MoO3／SiO2及非负载K－Mo催化剂进行硫化后，测试其合成醇活性．结果表明500℃焙烧制得的负载型催化剂显示较高的合成低碳烃活性和较低的合成低磷醇选择性，经800℃焙烧后，合成低磷醇的选择性大幅度提高．500℃焙烧的非负载K－Mo催化剂显示较高的合成醇选择性，经800℃焙烧后，促碳醇的选择性保持不变．用氨的吸附及TPD方法测定了各样品的酸性，并与催化剂活性对照，发现催化剂酸性越强，酸量越大，则其合成醇选择性越低．催化剂上的乙醇分解实验证实，催化剂的酸量大小与它的醇分解活性成正变关系，这些结果说明催化剂酸性对其合成醇性能有直接的影响．     

Effects of antimony on the surface tension of molten silicon

The effect of antimony concentration (C(Sb)/mass%) on the surface tension of molten silicon has been determined with the sessile drop method in the temperature range from 1693 to 1773 K and in the range of the oxygen partial pressure, Po(2), in an Ar atmosphere from 10(-23) to 10(-21) MPa. The results show that the surface tension of molten silicon decreases with increasing Sb concentration in the range of C(Sb)<0.9 mass%, which indicates positive adsorption of Sb in molten silicon and can be fairly described with the Szyszkowski's equation. The maximum decrease rate of surface tension is about 65 mN m(-1) (mass% C(Sb))(-1), and the temperature coefficient of surface tension, (partial differential sigma/ partial differential T)C(Sb), increases with increasing C(Sb). The evaporation of the systems was only observed between the melting points of antimony (904 K) and silicon (1683 K), and the surface tension presents no dependence on measuring time above the melting point of silicon.