Neriifolin S, a dimeric serine protease from Euphorbia neriifolia Linn.: Purification and biochemical characterisation

A dimeric serine protease Neriifolin S of molecular mass 94 kDa with milk clotting activity has been purified from the latex of Euphorbia neriifolia by anion exchange and size-exclusion chromatography. It hydrolyses peptidyl substrates l-Ala-pNA with highest affinity (K_m of 0.195 mM) and physiological efficiency (K_cat/K_m of 144.5 mM s). Enzyme belongs to the class of neutral proteases with pI value of 6.8, optimal proteolytic activity displayed at pH 9.5 and temperature 45 °C. Its proteolytic activity is strongly stimulated in the presence of Ca⁺² ions and exclusively inhibited by serine protease inhibitors. Enzyme is fairly stable toward chemical denaturants, pH and temperature. The apparent T_m, was found to be 65 °C. Thermal inactivation follow first order kinetics with activation energy (Ea), activation enthalpy (ΔH∗), free energy change (ΔG∗) and entropy (ΔS∗) of 27.54 kJ mol⁻¹, 24.89 kJ mol⁻¹, −82.34 kJ mol⁻¹ and 337.20 J mol⁻¹ K⁻¹.     

Dye-sensitized solar cell with the hole collector p-CuSCN deposited from a solution in n-propyl sulphide

A method is devised for the deposition of CuSCN on ruthenium bipyridyl dye coated nanocrystalline TiO₂ films from a solution in n-propyl sulphide. The dye-sensitized solid state photovoltaic cell formed was found to yield higher short-circuit photocurrent, open-circuit voltage and efficiency compared to the cells made with CuSCN by other deposition techniques. Factors affecting the stability of the cell are investigated.     

硫氰化铵固-固相变贮热及变温红外研究

用ＤＳＣ法研究无机塑晶材料硫氰化铵从室温到２２０℃之间的热物理性质,探讨其贮热可跑性,并利用变温红外光谱仪分析硫氰化铵固－固相变的机理。     

汞（Ⅱ）—硫氰酸盐—罗丹明B—聚乙烯醇显色体系的研究和应用

在非离子表面活性剂聚乙烯醇存在下,汞与硫氰酸盐和罗丹明Ｂ在水相中形成紫红色的离子缔合物,其最大吸收波长为６２０ｎｍ在０～６μｇ／２５ｍＬ范围内服从Ｂｅｅｒ定律,表观摩尔吸光系数为２．１６×１０５Ｌ·ｍｏｌ－１·ｃｍ－１该法灵敏度高,选择性好,操作简便,可直接在水相中测定微量汞     

Nature of the polarographic prewaves of Ni(II) in the presence of thiocyanate

The nature of the polarographic prewaves of Ni(II) in the presence of thiocyanate has been analysed using different criteria. The catalytic character of both prewaves has been shown although the second one has a mixed adsorption-catalytic character. The bulk nature of the first prewave and the surface nature of the second prewave are also demonstrated.     

绿色环保溶剂在5-乙硫基-1H-四氮唑制备上的应用

以水为溶剂,少量乙醇作增溶剂合成5-乙硫基-1H-四氮唑。对影响反应收率的溶剂配比、反应温度、反应时间及物料配比各因素进行了研究,确定了反应的最佳条件,总收率达83.5%,反应物料的用量大大降低。     

硫氰酸盐提金中间试验研究

本文介绍了硫氰酸盐法从高铜、高硫金精矿中提金的中间试验研究。对金的学好以率、硫氰酸钠的消耗量，锌粉置经及制取海绵金等提出了结果，指出了存在的问题，并对一些有关总是问题进行了讨论。     

无溶剂条件下微波辅助合成硫氰酸酯类化合物

芳基硫氰酸酯是重要的有机合成中间体,得到越来越广泛的应用。文章研究了无溶剂条件下微波辅助合成的方法,用此方法合成了一系列的芳基硫氰酸酯。反应在几分钟内就能完成,并且收率大多在80%以上。该方法操作简单,反应时间短,产率高,环境友好,符合绿色化学的发展要求。