催化光度法测定痕量甲醛

基于磷酸介质中甲醛催化溴酸钾氧化溴甲酚紫的褪色反应 ,建立了测定痕量甲醛的方法。方法的检出限为 1.0× 10 - 5g·L- 1,线性范围为 0 .0 2 0～ 0 .4 8μg·ml- 1,方法简便 ,用于空气中测定痕量甲醛 ,结果满意。     

具有强绿色荧光发射效应的2，2′-二硝基4，4′-联苯酸铀(Ⅵ)配聚物

A very complex 3D Uranium(Ⅵ) metal-organic framework was obtained by the hydrothermal treatment of UO₂(NO₃)₂·6H₂O with (R，S)-2，2′-dinitro-biphenyl- 4，4′-dicarboxylic acid (BTNCA) (L) in water at 180 ℃ in Pyrex tubes. The crystal belongs to monoclinic system with space group P2₁/c， and a=0.545 90(3) nm， b=3.676 01(18) nm， c=2.659 81(13) nm， β=91.4060(10)°， V=5.335 9(5) nm³， Z=4. CCDC: 659615.     

DFT Investigations About Pyrazine Molecules on Si(100)-2×1 Surface

It is important to understand the interface of aromatic molecules on semiconductor surfaces because of the rich functionality of such molecules on semiconductor surfaces. The chemisorption of pyrazine molecules on the Si( 100)-2×1 surface has been investigated using the B3LYP density functional theory with Si9H12 one-dimer and Si15H16 twodimer cluster models. The calculated results predict that N-dative bonded-state, C2= C5 [ 4 2 ] and the tightbridge1, 2, 5,6 products may coexist on the Si(100)-2×1 surface.     

4fN-15d组态自旋允许与禁戒跃迁能级的研究

通过稀土光谱理论，计算了三价稀土离子的4f^N-15d组态能级的f与d电子间的库仑相互作用，结果表明对于重稀土元素，其自旋允许跃迁能级位置高于自旋禁戒跃迁能级位置，并且两种能级间的能级差随f电子数的增加而依次减小。对于轻稀土元素,则自旋禁戒跃迁能级位置高于自旋允许跃迁能级位置。结果很好地解释了自旋禁戒跃迁能级的光谱现象。     

一维棒状ZnO的制备及电化学嵌锂性能研究

目前,商业化锂离子电池一般采用石墨作为负极材料,因其电位与金属锂电极的电位很接近,所以当电池反复循环和过充时,石墨表面易析出金属锂,会因形成枝晶而短路。在温度过高时还容易引起热失控。同时,锂离子电池的容量在很大程度上取决于负极的锂嵌入量,而且石墨材料容量相对较低     

Preparative high-speed counter-current chromatography for purification of shikonin from the Chinese medicinal plant Lithospermum erythrorhizon

The bioactive compound shikonin was successfully isolated and purified from the crude extract of the traditional Chinese medicinal plant Lithospermum erythrorhizon Sieb. et Zucc. by preparative high-speed counter-current chromatography (HSCCC). The preparative HSCCC was performed using a two-phase solvent system composed of n-hexane-ethylacetate-ethanol-water (16:14:14:5 (v/v)). A total amount of 19.6 mg of shikonin at 98.9% purity was obtained from 52 mg of the crude extract (containing 38.9% shikonin) with 96.9% recovery. The preparative isolation and purification of shikonin by HSCCC was completed in 200 min in a one-step separation.     

各种离子对血卟啉与牛血清白蛋白相互结合反应的影响研究

应用荧光法研究了水溶液体系中血卟啉与牛血清白蛋白分了间相互结合反应，其结合常数ＫＡ＝２．２×１０＾４，结合位置数为１．依据Ｆｏｒｓｔｅｒ非辐射能量转移机理，探讨了血卟啉与牛血清白蛋白相互结合时，其给体－受体间距离和能量转移效率，进一步研究了各种离子与牛血清白蛋白的结合反应，其结合淬灭能力大小顺序为Ｃｒ（Ⅵ）〉Ｆｅ＾３＋〉Ｃｕ＾２＋〉ＮＯ２〉Ｂｒ＾－，并探讨不同阴，阳离子及血卟啉与牛血清白蛋白间相互     

多壁碳纳米管修饰玻碳电极伏安法测定氯霉素

研究了氯霉素(CAP)在多壁碳纳米管修饰玻碳电极上的电化学行为.发现在pH=2.0的0.1 mol/LKCl-HCl底液中,CAP在该修饰电极上有一灵敏的还原峰(Ep=-0.36 V vs.Ag/AgCl),峰电流与CAP浓度成正比,线性范围为6.0×10-6~2.7×10-4mol/L,检测限达3.0×10-6mol/L.该方法灵敏、准确,用于模拟样品和实际样品的测定,结果满意.     

羧甲基壳聚糖/聚乙烯醇/甘油环氧树脂蛇笼型复合螯合膜的制备及对金属离子的吸附性能

以交联甘油环氧树脂交联的聚乙烯醇(PVA)为笼树脂，羧甲基壳聚糖(CCTS)为蛇树脂制备了具有蛇笼结构的复合螯合膜，研究了其对Cu^2 、Ni^2 、Pb^2 、Fe^3 、Zn^2 ，Hg”^2 、Cd^2 等金属离子的吸附性能，研究表明，该树脂对Cu^2 、Ni^2 、Pb^2 有较好的吸附性能，其中PVA是对Cu^2 的吸附的主要贡献者，而CCTS则是在对Ni^2 的吸附中起主要作用。该树脂可以用于含Cu^2 废水的处理。     

Heterocycloaddition of thermally generated 1,2-diaza-1,3-butadienes to [60]fullerene

Stable C₆₀-fused tetrahydropyridazine derivatives were synthesized through the hetero-Diels-Alder cycloaddition of C₆₀ with 1,2-diaza-1,3-butadienes, which were generated in situ by the thermal extrusion of sulfur dioxide from 2,5-dihydro-1,2,3-thiadiazole-1,1-dioxides.