介绍一种改进内压力盐效应公式的计算方法

式中k_s为盐析常数,c_s为盐的浓度,分别为非电解质和盐在无限稀释溶液中的偏摩尔体积,V_s为盐在液体状态下的摩尔体积,β_o为水的压缩系数,p_e为盐溶于水而产生的有效压力。此式推导过程中所用的极限条件为V_n→0,因此(1)式仅能用在极小的非电解质分子上,对于苯及苯的衍生物讲,K_s计算值约为实验值的2～3倍。当非电解质体积较大时,Mc-     

氢氧化铝镁正电溶胶制备及性能研究

氢氧化铝镁正电溶胶制备及性能研究侯万国，张春光，孙德军，梁晓丽，王果庭（山东大学胶体与界面化学研究所，济南，２５０１００）关键词混合金属氢氧化物，溶胶，超细颗粒混合金属氢氧化物的合成、组成及结构等已得到广泛研究［１，２］．我们也曾用插入法合成了混合金...     

Synthesis,characterization and interaction of mixed polypyridyl ruthenium(II) complexes with calf thymus DNA

New mixed polypyridyl {HPIP = 2-(2-hydroxyphenyl)imidazo[4,5-f][1,10]phenanthroline, phen = 1,10-phenanthroline, dmp = 2,9-dimethyl-1,10-phenanthroline, dmb = 4,4-dimethyl-2,2-bipyridine} ruthenium(II) complexes [Ru(phen)₂(HPIP)]²⁺, [Ru(dmp)₂(HPIP)]²⁺ and [Ru(dmb)₂(HPIP)]²⁺ were synthesized and characterized by elemental analyses ¹H-n.m.r., u.v.–vis. spectroscopy and cyclic voltammetry. Their DNA-binding properties were demonstrated by absorption, luminescence titrations, steady-state emission quenching and viscosity measurements. The results suggested that all the examined complexes bind with CT-DNA intercalatively. Methyl groups substituted at the 4,4-positions of bpy has no obvious effect on its DNA binding, whereas substituents at the 2- and 9-positions of phen have an impressive effect on its DNA-binding, as revealed by the decreased binding affinity.     

Crystal Structure and Characterization of a Large Polyoxotungstate (NH4)21{La(H2O)5[Ni(H2O)]2As4W40O140}·53H2O

The heteropolytungstate (NH4)₂₁{La(H₂O)₅[Ni(H₂O)]₂As₄W₄₀O₁₄₀}·53H₂O is obtained by the reaction of Na₂₇[NaAs₄W₄₀O₁₄₀]· 60H₂O with NiCl₂·6H₂O, La(NO₃)₃·6H₂O and NH₄Cl at pH‐4.5. The structure and chemical composition are determined by X‐ray diffraction analysis and elemental analysis. The crystal data and main structure refinement are a = 1.9551(3) nm, b = 2.4156(4) nm, c= 3.7068(6) nm, β = 91.505(3)°, V = 17.500 (5) nm³, monoclinic crystal system with space group P2₁/n, Z = 4, R₁ = 0.0573, wR₂ = 0.0717 [I >2<s?(I)], R₁, = 0.2463 and wR₂ = 0.1199 (all data). [La(H₂O)₅] {Ni(H₂O)}₂AS₄W₄₀O₁₄₀ has C₂, symmetry. IR spectra of the ligand [NaAs₄W₄₀O₁₄₀]^27‐ and its three complexes were discussed.     

A Novel Green Preparation of a, a''''-Bis (substituted benzylidene)-cycloalkanones Promoted by FeCl_3 6H-2O in Ionic Liquid

a, a'-Bis(substituted benzylidene)cycloalkanones were efficiently prepared from cycloalkanones and benzaldehydes in [bmim][BF4] by using iron(III) chloride hexahydrate as a catalyst. It is shown that [bmim][BF4] and iron(III) chloride hexahydrate can be quantitatively recovered and be reused effectively for many times. Compared with the known methods, this novel process has the advantage of being an envkonmentally benign process together with good yields and mild reaction conditions.     

稀土复合型柴油催化助燃剂的研制及应用

采用铈、铂的有机配合物及碳酸酯制备出一种稀土复合型柴油催化助燃剂.通过发动机台架试验,表明添加剂可有效降低碳烟PM和NOz排放,并且发动机热效率有所提高.     

罗丹明B-Mo(V)-SCN~--PVA体系荧光熄灭法测痕量钼

在聚乙烯醇存在下,用罗丹明B-Mo(V)-SCN~-荧光熄灭法测Mo,能消除过量的SCN-对罗丹明B的熄灭作用。加入聚乙烯醇后体系的荧光熄灭倍数比未加入时大14倍。此法灵敏度高、稳定性好、操作简便,检测下限0.12ng/ml Mo.可用于测水和头发中的钼。     

儿童易疲劳与血清中微量元素含量的相关性研究

测定了1562名儿童(其中包括153名易疲劳儿童)血清中Zn、Fe、Cu、Ca、Mn和Pb的含量。研究发现,易疲劳儿血清Ca含量(84.4±12.5μg/mL)显著低于对照组儿童(88.5 4±13.4μg/mL),P<0.05;Fe含量(1.094±0.22μg/mL)显著高于对照组儿童(1.07 4±0.22μg/mL),P<0.05;Mn含量(0.040 4±0.035μg/mL)非常显著高于对照组儿童(0.035 4±0.013μg/mL),P<0.001。     

聚丙烯中空纤维膜的微孔结构的控制

通过熔纺／冷拉伸法制备了微孔聚丙烯中空纤维膜。研究了工艺条件对微孔聚丙烯中空纤维膜的微孔结构与性能的影响。结果表明：随着纺丝温度的下降或熔体拉伸比的提高，最大可几孔径及孔隙率增大；熔纺中冷却风速提高，最大可几孔径及孔隙率较大；温度低于110℃时，热处理对最大可几孔径及孔隙率的影响较小，在120－130℃时，随着热处理温度的增加，最大孔径及孔隙率有明显增加的趋势；随着初纺中空纤维拉伸倍数的增加，孔隙率先增加而后下降。     

{Cu[H_2NC(CH_2OH)_3]_2}{Pic}_2·H_2O的合成与晶体结构

三羟甲基氨基甲烷与苦味酸(Pic)铜在乙醇水混合液中反应,制得少见的不对称氢键连接的超分子化合物{Cu[H2NC(CH2OH)3]2}{Pic}2?H2O。晶体属三斜晶系,空间群为P ,晶胞参数为a = 6.894(1),b = 8.219(1),c = 13.543(3) ? ?= 79.290(1),?= 8 3.36(2), ?= 84.590(1)埃轿狢20H30CuN8O22,V = 746.9(2) 3,Z = 1,Dc = 1.774 g/cm3,F(000) = 411,?= 0.844 mm-1,R = 0.0334,Rw = 0.0863。在配合物的结构单元中, Cu2+位于对称中心,分别与2个四齿配体(三羟甲基氨基甲烷)中的2个OH,1个NH2,三齿配位,呈笼状螯合。而另一个OH,因配体和中心离子构型的限制,不参与配位。