Cu-Zn-Sn体系富Sn区液相限的研究

近些年来,无铅低熔点填料日渐引起人们的兴趣,且将得到广泛的应用。Cu-Zn-Sn合金正是无铅低熔点填料的一种基本合金。该体系相图虽有一些报道,但他们的研究只涉及富铜区(>50Wt％)的液相限和等温截面(500℃)。我们颇感兴趣的富Sn区的液相限,尚未见文献报道,因此测定该体系富Sn区的液相限是必要的。关于Cu-Zn-Sn体系的三个相关二元体系,已有文献报道,也较成熟。对于Cu-Zn体系,富Zn区600℃以下存在两个转熔反应,其转熔点分别为Q(～88Wt％Zn,598℃),W(97.5-98.5Wt％Zn,424℃);Cu-Sn体系富Sn区有一个转熔反应,其转熔点     

安培检测芯片毛细管电泳及其初步应用

An end-channel amperometric detector with a guide tube for working electrode was designed and integrated on a home-made glass microchip. The guide tube was directly patterned and fabricated at the end of the detection reservoir, which made the fixation and alignment of working electrode relatively easy. The fabrication was carried out in a two-step etching process. A 30 μm carbon fiber microdisk electrode and Pt cathode were also integrated onto the amperometric detector. The baseline separation of dopamine (DA), catechol (CA) and epinephrine (EP) was achieved within 80 s. Relative standard deviations of not more than 5.2% were obtained for both peak currents and migration times of DA and CA (n=5). Using standard adding method, DA in tLrine and plasma samples was detected. The recoveries were in the range of 83%—103%.     

Studies of some new bioactive acrylic esters

Four typical bioactive esters of acrylic monomers, N-p-acryloxybenzoyloxysuccinimides, 3-ac-ryloxy-4-oxo-3,4-dihydro-1,2,3-benzotriazines, N-acryloxy-5-norbornene-2,3-dicarboximides, and I-p-acryloxybenzoyloxybenzotriazoles, were Synthesized and polymerized as reactive polymers. Twelve new monomers were prepared by coupling acrylic acid, methacrylic acid, p-acryloxybenzoic acid, or p-methacryloxybenzoic acid with four N-hydroxy compounds such as N-hydroxysuccinimide (HOSu), 3-hydroxy-4-oxo-3,4-dihydro-1,2,3-benzotriazine (HOObt), N-hydroxy-5-norbornene-2,3-dicarboximide (HONB), and I -hydroxybenzotriazole (HOBT) in the presence of dicyclohexylcarbodimide. All monomers polymerized readily in solution with azobisisobutyronitrile (AIBN) as free radical initiator. The resulting reactive polymers with reactive ? OSu, ? OObt, ? ONB, or ? OBT group on the side chain are equally reactive toward n-butylamine at room temperature in the formation of corresponding polyacrylamides. Reactive polymers were used to immobilizetrypsin. It has been found that poly(N-p-methacryloxybenzoyloxy-5-norbornene-2,3-dicarboximide)-trypsin matrix had high activity around three times that of the poly(N-methacryloxy-5-norbornene-dicarboximide)-trypsin matrix. It is proposed that this activity may be due to the presence of a long spacer arm with a hydrophobic and rigid benzene ring between the ligand and matrix. The reactive poly(N-p-methacryloxybenzoyloxysuccinimide-p-methacryloxybenzoic acid) copolymer was used to immobilize the serum protein. This immobilized protein was a hopeful bioactive solid immunoadsorbent.     

A Novel Environmentally Benign Method for the Selective Oxidation of Alcohols to Aldehydes and Ketones

In the presence of [Ru(terpyridine)(2,6‐pyridinedicarboxylate)], aliphatic and benzylic alcohols are oxidized to the corresponding aldehydes or ketones with high selectivity by using hydrogen peroxide as the oxidant. There is no need for the addition of co‐catalysts or organic solvents. By applying an optimized reaction protocol, high catalyst productivity (turnover number>10 000) and activity (turnover frequency up to 14 800 h^?1) has been achieved.     

光同时诱导水中Cr(Ⅵ)的还原与橙黄Ⅱ的氧化

光同时诱导水中Cr(Ⅵ)的还原与橙黄Ⅱ的氧化;染料;橙黄Ⅱ;Cr(Ⅵ);光还原;光降解     

Synthesis and Insulin—sensitizing Activity of a Series of 2—Benzyl—1,3—dicarbonyl Derivatives

A series of 2-benzyl-1,3-dicabonyl derivatives was synthesized.Their insulin-sensitizing activity was evaluated in 3T3-L1 preadipocyte cells.Compounds3,26 and 27 were found to possess strong insulin-sensitizing activity in vitro and were selected for further hypoglycemic evaluation in vivo.     

苯乙烯-4-甲基丙烯酰氧-2.2.6.6-四甲基哌啶共聚物的250兆赫~1H-核磁共振研究

本文用250兆赫~1H-核磁共振技术研究了苯乙烯(S)-4-甲基丙烯酰氧-2、2.6.6-四甲基哌啶(M)自由基引发聚合的共聚物的组分比和微结构,定量测定了以M为中心的三元组分布。由此确认该共聚体系属于一级马尔可夫链模型,并确定了单体竞聚率常数,r_M=0.32,r_S=0.60。对苯乙烯含量较多的共聚物还定量估计了以S为中心的三元组分布,与理论上计算结果有很好的一致性。     

Angular distributions of photoelectrons in resonantly enhanced multiphoto ionization via the 7s[1 1/2]0 1 and 8s[1 1/2]0 1 states of Xe

Photoelectron angular distributions have been measured for the three-photon resonant one-photon ionization, (3+1), of Xe via the 7s[1 1/2]⁰ ₁ and 8s[1 1/2]⁰ ₁ states. The results are in good agreement with the theoretical predictions of Tang and Lambropoulos [13] for the 8s[1 1/2]⁰ ₁, but not for the 7s[1 1/2]⁰ ₁ state. Furthermore, the results are compared to those which have been obtained by Blazewicz et al. [1] for the three-photon resonant two-photon ionization, (3+2), of Xe via the 6s[1 1/2]⁰ ₁ state.     

计算金属间化合物热力学性质的新方法

用一简单的相关函数式对金属间化合物的热力学性质进行拟合，提出了一种计算金属间化合物热力学性质的新方法，并用此方法计算了二元金属间化合物的常温热容和熵。计算结果表明，该方法简单，且能满足一定的计算精度，有一定的实用价值。     

老年性白内障与微量元素

参阅有关老年性白内障的文献．归纳其病因有四种学说:(1)老化学说;(2)醌体学说;(3)微量元素学说;(4)中医学说．按病因学说不同．用药各异．目前治疗老年性白内障药物有滴眼剂及内服剂,其中有一种新药名为除障灵．它是根据中医学说及微量元素学说，筛选中药制成,它含有丰富的锌、硒、铜、镁等微量元素．应用除障灵治疗老年性白内障患者102例(204只眼)，观察6个月至2年，有效率达95％，开创了治疗老年性白内障的新方法．