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1.
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   

2.
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   

3.
镧系元素钨硅杂多配合物异构体的合成与表征   总被引:5,自引:0,他引:5  
关于[Ln(XM_(11)O_(39))_2]~(n-)类配合物合成有一些报道,但它们均未指出其中配体及所得配合物的构型,本文以α-和β_2-SiW_(11)O_(39)~(8-)为配体,首次合成了双-(11-钨硅酸根)合镧系元素钾盐的异构体并进行了结构表征。 1 实验部分 1.1 仪器和试剂 pHS-2型酸度计;883型笔录式极谱仪,384B型极谱分析仪,阿尔法  相似文献   

4.
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   

5.
镧系元素钼系双11系列杂多蓝的离析和性质研究   总被引:1,自引:0,他引:1  
本文首次报道了镧系元素钼系双11系列两电子杂多蓝K_yH_z[Ln(XMo_(11)O_(39)_2]·nH_2O(X=P,Ln=La、Ce、Pr、Nd、Sm、Gd;X=Si,Ln=Ce、Pr、Sm、Tb、Dy;X=Ge、Ln=Dy)的制备和离析方法.并通过元素分析、红外光谱、可见-紫外光谱、极谱、循环伏安、热分析、ESR、~(31)P NMR、XPS对产物进行了表征及性质研究.结果表明:杂多蓝阴离子结构较之还原前发生了轻微畸变,还原电子具有一定的离域性.在溶液中杂多蓝较还原前的杂多酸(盐)具有略强的氧化能力.溶液中杂多蓝的氧化能力Ln-P(2)>Ln-Si(2).热稳定性Ln-P(2)>Ln-Si(2).该系列杂多蓝还具有较好的抗碱解能力.  相似文献   

6.
过渡元素及镧系元素11-钨锰杂多酸钾配合物的合成与性质   总被引:4,自引:0,他引:4  
本文合成了以11-钨锰杂多阴离子为配体的4个配合物:K_6Z(H_2O)MnW_(11)O_(39)xH_2O(Z=ZD、Ni)和K_(13)Ln(MnW_(11)O_(39))_2·xH_2O(Ln=La、Nd)。用化学分析、离子交换、电导滴定、IR、UV、x-射线光电子能谱等进行了表征,还对其热性质等进行了研究。  相似文献   

7.
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   

8.
具有Keggin衍生结构,以α-[SiW_(11)(RSiOSiR)O_(39)]~(4-)(R=C_2H_5、C_6H_5、NC(CH_2)_3、C_3H_5)为阴离子的杂多酸盐已有报道,但以[XW_9Mo_2(RSiOSiR)O_(39)]~(n-)为阴离子的杂多酸盐尚未见报道。本文首次合成六种以[XW_9Mo_2(CH_3SiOSiCH_3)O_(39)]~(n-)以及[XW_(11)(CH_3SiOSiCH_3)O_(39)]~(n-),(X=Si,P,Ge)为阴离子的杂多酸四丁基铵(TBA)盐,并对它们进行了表征。  相似文献   

9.
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   

10.
镧系元素杂多钨砷酸盐的合成与性质研究   总被引:8,自引:2,他引:6  
本文报道了镧系元素的杂多钨砷酸钾K11[Ln(AsW11O39)2]·xH2O(Ln:La、Ce、Pr、Nd、Sm)的合成方法和X-射线粉末衍射、红外及拉曼光谱、X-光电子能谱及有效磁矩的研究结果。  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.
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   

15.
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   

16.
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   

17.
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   

18.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

19.
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   

20.
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