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1.
首次合成和离析了八种以缺位型Dawson结构钼磷杂多阴离子为配体的稀土杂多蓝K_(17)H_2[Ln-(P_2Mo_(17)O_(61))_2]·nH_2O和K_(17)H_4[Ln(P_2Mo_(17)O_(61))_2]·nH_2O(Ln=La,Pr,Sm,Yb).通过元素分析、电位滴定、红外光谱、紫外光谱、极谱、循环伏安、X射线光电子能谱、热重-差热分析和电子顺磁共振对杂多蓝进行了表征.实验结果表明,杂多阴离子还原为杂多蓝后,性质发生了某些变化,但结构基本不变,配体P_2Mo_(17)O_(61)~(10-)仍为a_2型.  相似文献   

2.
镧系元素的双—(9-钨-2钼硅)杂多酸钾的合成与性质研究   总被引:1,自引:0,他引:1  
本文报道了镧系元素的杂多钨钼硅酸钾K_(13)[Ln(SiW_9Mo_2O_(39))_2]·xH_2O(Ln=La、Ce、Pr、Nd、Sm、Eu、Gd)的合成方法.通过元素分析、红外、紫外光谱、X射线粉末衍射、磁化率测定和差热-热重分析等手段,对配合物进行了表征.  相似文献   

3.
合成了具有Keggin结构的杂多化合物K_7PW_(11)O_(39)·xH_2O(简写为PW_(11)),K_5PW_(11)ZO_(39)·xH_2O(Z=Mn~(Ⅱ),Co~(Ⅱ),简写为PW_(11)Mn,PW_(11)Co)和Dawson结构的杂多化合物H_6P_2W_(18)O_(62)·xH_2O及其钾盐K_6P_2W_(18)O_(62)·xH_2O(简写为P_2W_(18)和K_(10)P_2W_(17)O_(61)·xH_20(简写为P_2W_(17)),K_8P_2W_(17)ZO_(61)·xH_2O(Z=Mn~(Ⅱ),Co_(Ⅱ),简写为P_2W_(17)Mn,P_2W_(17)Co)。用热差热重、红外光谱、X射线衍射、循环伏安等技术对这类杂多化合物的性质进行了系统的研究,并对其结构和催化活性的关系进行了探讨。  相似文献   

4.
合成了通式为K_(13)[Ln(β_i-SiW_(11)O_(39))_2]·xH_2O(Ln=La,Ce,Pr,Nd,Sm,Gd,Er;β_i=β_1,β_3)的两个系列的β-异构体。通过元素分析、极谱、循环伏安法,UV和VIS光谱、磁化率以及热分析等手段研究了异构体的组成和性质。  相似文献   

5.
镧系元素钨硼杂多酸盐的合成及性质研究   总被引:3,自引:0,他引:3  
钨硼杂多配合是一类性能良好的催化剂,它还具有抗病毒作用,也可用于乳糖酶分离、纤维素光解剂及用于制造耐热油漆等,本文报道了K_(15)[Ln(BW_(11)O_(39))_2]·xH_2O(简称  相似文献   

6.
11-钨钛合过渡金属杂多酸钾的合成与性质   总被引:3,自引:0,他引:3  
11-系列不饱和杂多阴离子可作为配体与过渡金属或希土离子生成混合型杂多阴离子。由于这种无机高分子配合物对某些有机合成反应具有催化活性及抗病毒性能,新型化合物的合成仍吸引着人们的关注。11-钨钛杂多阴离子除与希土离子生成K_(13)[Ln(TiW_(11)O_(39))_2]·xH_2O型化合物外,也可与过渡金属离子生成混合型杂多阴离子。本文报道了K_n[TiW_(11)M(H_2O)O_(39)]·xH_2O(M=Mn~(2+)、Cu~(2+)、Zn~(2+)、Fe~(3+),Co~(3+)和Cr~(3+))型杂多酸盐的合成与性质。  相似文献   

7.
The present paper reports eight heteropoty blues of double 2:17 motybdophosphates tanthanide comptexes with tacunary Dawson structure, i.e., K_(17)H_2[Ln(P_2Mo_2~ⅤMo_(15)~ⅥO_(16))_2], nH_2O and K_(17)H_4 [Ln(P_2Mo~Ⅴ_4Mo_(13)~ⅥO_(61))_2], nH_2O(Ln=La, Pr, Sm, Yb). They were characterized by etementat anatyses, potentiometric titration, IR, UV, potarography, cyclic vottammetry, X-ray photoelectron spectra, X-ray powder diffraction, thermat analyses and ESR. The results show that the properties of these heteropoty btues are different from those of heteropoty blues with saturated Dawson structure and other tacunary series. They are more stabte than their parent heteropoty acids in aqueous sotution and have the abitity of anti-base decomposition.  相似文献   

8.
双-11钨钛希土三元杂多化合物的合成与性质研究   总被引:7,自引:1,他引:7  
本文报道了双-11钨钛希土三元杂多化合物K_(13)[Ln(TiW_(11)O_(39))_2]·xH_2O(Ln=La,Ce,Pr,NdSm,Eu,Gd,Tb,Dy,Ho,Er,Yb,Y,Ce(Ⅳ))的合成方法,溶液性质,红外光谱,紫外光谱,X光电子能谱,热分析等的研究结果.  相似文献   

9.
自1971年Peacock等首次合成出以杂多阴离子为配位体的镧系元素的一些杂多配合物[Ln(XW_(11)O_(39))_2]~(n-)(X=P,Si)以来,Zuhairi等又合成出镧的一些其它杂多钨酸盐[La(XW_(11)O_(39))_2]~(n-)(X=B,Si,Ge,P,As)。 为开发新型的镧系元素催化剂,我们系统地研究了镧系元素的杂多钨酸盐和杂多钼酸盐。本文报道有关K_(11)[Ln(PW_9Mo_2O_(39))_2]·nH_2O(Ln=La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Er,Yb)的合成及性质的研究结果。  相似文献   

10.
研究了K_(10)H_3[Ln(SiMo_(11-n)W_nO_(39)_2]·mH_2O(n=5,7,9;Ln=La~(3+),Ce~(3+),Pr~(3+),Nd~(3+),Sm~(3+),Eu~(3+),Gd~(3+),Dy~(3+),Yb~(3+))的合成方法。测定了K_(10)H_3[Pr(SiMo_6W_5O_(39))_2]·30H_2O的晶体结构,P2_1/n空间群,晶胞参数:a=1.7134(3)nm,b=2.6896(5)nm,c=2.1232(3)nm,β=103.60(3)°,Z=4.讨论了所合成配合物的IR光谱、电子光谱和X射线扮末衍射的特征。热分解性质研究结果表明,不同系列的配合物的分解温度范围:n=5,250~300℃;n=7,300~350℃;n=9,350~400℃。  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。  相似文献   

15.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

16.
袁丽秋 《化学教育》2006,27(5):8-10
面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。  相似文献   

17.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

18.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

19.
黄酮化合物的合成研究进展   总被引:2,自引:0,他引:2  
黄酮化合物是一类具有多种生物活性的天然产物,其经典的合成方法主要为查耳酮路线和β-丙二酮路线.近年来出现了许多新技术、新方法.本文介绍了2'-羟基查尔酮的氧化关环法、黄烷酮氧化法、改进的Baker-Venkataraman法及其他合成黄酮化合物的方法.  相似文献   

20.
采用原位红外光谱技术,以噻吩、环己烯和苯为模型探针分子,分别考察单一烃分子在NiY分子筛上的吸附与反应行为以及噻吩与烯烃、芳烃间的竞争吸附和催化反应行为。单一探针分子吸附研究发现,NiY分子筛中与Ni物种相关的Lewis(L)酸位是噻吩的选择性吸附活性位;噻吩和环己烯在NiY分子筛中Brnsted(B)酸位上发生的质子化和低聚反应明显弱于HY分子筛。双探针分子竞争吸附研究发现,环己烯二聚体在NiY中强B酸位上的强化学吸附与噻吩存在显著的竞争吸附行为。另外,苯和噻吩在NiY上的竞争吸附现象在373K时明显减弱。由此,在选择性吸附脱硫过程中,减少吸附剂表面B酸中心可降低烯烃对噻吩的竞争吸附,另外适当提高吸附体系的温度可以有效避免芳烃对噻吩的竞争吸附。  相似文献   

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