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1.
氨基酸及其希土配合物的热化学性质研究   总被引:2,自引:0,他引:2       下载免费PDF全文
用转动弹热量计测定了CL-α-氨基正丁酸的燃烧能,换算它的标准生成焓。并且计算了组成为BECl3.B2.5H2O(RE=Eu,Gd,Dy,Er,Yb,Y;B=α-氨基正丁酸)的固态配合物的标准生成焓。  相似文献   

2.
制备了RECl3·3H2O(RE=Pr、Gd)与18C6的固态配合物,其化学组成为:RECl3·18C6·3H2O.对其进行了IR、溶解度、DTG和TG分析.推测了热分解机理.测量了298.15K时18C6及两种配合物在无水乙醇中的积分溶解热,以及RECl3·3H2O在18C6-C2H5OH溶液中的溶解配位热效应.依据本文所设计的热化学循环,求得了RECl3·3H2O(s)与18C6(S)生成RECl3·18C6·3H2O(S)的反应热及两种配合物的标准生成焓.  相似文献   

3.
合成了两种稀土高氯酸盐与L-脯氨酸配合物的晶体.经热重、差热、化学分析及对比有关文献,知其组成 是[Pr2(L-Pro)6(H2O)4](ClO4)6和[Er2(L-PrO)6(H2O)4](ClO4)6,质量分数为99.24%和98.20%.选用RE(NO3)· 6H2O(RE=Pr,Er)、LPro、NaClO4·H2O和 NaNO3作辅助物,使用具有恒温环境的反应热量计,以 2 mol·L-1HCl 作溶剂,分别测定了[2RE(NO3)3·6H2O+6L-PrO+6NaClO4·H2O]和{ [RE2(L-PrO)6(H2O)4](ClO4)6+6NaNO3}在 298.15 K时的溶解热.设计一热化学循环求得化学反应的反应焓rH分别是:63.904 kJ·mol-1和 91.017 kJ·mol-1,经计算得配合物[RE2(L-Pro)6(H2O)4](ClO4)6(s)在 298.15 K时的标准生成焓(298.15 K)分别 是-6 594.78 kJ·mol-1和-6 532.87 kJ·mol-1。  相似文献   

4.
制备了RECl3.3H2O(RE=Pr,Gd)与18C6的固态配合物,其化学组成为:RECl3,18C6.3H2O。对其进行了IR,溶解度、DTG和TG分析,推测了热分解机理,测量了298.15K时18C6及两种配合物在无水乙醇中的积分,及RECl3,3H2O在18C6-C2H2OH溶液中的溶解配位热效应,依据本文所设计的热化学循环,求得了RECl3,3H2O(s)与18C6(s)生成RECl3,  相似文献   

5.
RE(NO3)3与丝氨酸间配合行为的半微量相平衡研究   总被引:3,自引:0,他引:3  
测定了RE(NO3)3-Ser-H2O(RE=Sm,Gd,Yb)三元体系在25℃的溶度和饱和溶液折光率,各体系的溶度曲线和饱和溶液折光曲线均由四支组成,分别与RE(NO3)3.nH2O(RE=Sm,Gd,n=6;RE=Yb,n=5)配合物RE(Serime)(NO3)3.4H2O(一致溶解化合物),RE(Serine)4(NO3)3.6H2O(不一致溶解化合物)和Serine相对应。  相似文献   

6.
用转动弹量热计测定了稀土(Ce、Nd、Sm、Eu、Gd、Dy、Er、Yb)硝酸盐与DL-a-丙氨酸(1:4)配合物的燃烧热-△_cu(J·g ̄(-1)),其结果依次为9596.1,8874.7,8710.1,8937.3,8961.3,8751.8,8700.0和8656.4。据此计算的生成焓-△_fH(kJ·mol ̄(-1))分别为3393.53,3671.37,3740.82,3495.21,3497.52,3626.79,3641.64和3568.58。这些结果不但为稀土元素的三分组提供了可靠的实验依据,亦发现了RE(NO_3)_3·(CH_3CHNH_2COOH)_4·H_2O配合物稳定性之变化规律与稀土原子序数的关系。  相似文献   

7.
稀土与氨基酸固体配合物的合成及生物活性的研究   总被引:17,自引:2,他引:17  
用稀土硝酸盐与γ-甲基-α氨基戊酸(白氨酸,C6H(13)NO2)制得了8种组成为RE(Leu)3(NO3)3·nH2O(RE=La、Ce、Pt、Nd、Sm、Eu、Yb、Y,n=1~3)的新固体配合物;与δ-胍基-α氨基戊酸(精氨酸,C6H(14)N4O2)制得了4种组成为RE(Arg)n(NO3)3.mH2O(RE=La、Pr、Nd、Sm,n=2~3,m=1~3)的新固体配合物。经元素分析、IR、摩尔电导及核磁共振时配合物进行厂表征。选用部分稀上盐,配合物及氨基酸分别对5种细菌、2种霉菌进行了生物活性试验,证明稀士氨基酸配合物均具有抑菌或杀菌作用。  相似文献   

8.
稀土溴化物与甘氨酸配合物标准摩尔生成焓的测定   总被引:2,自引:0,他引:2  
采用量热法在29815±010K测量了REBr3·3Gly·3H2O(RE=La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Y;Gly为甘氨酸)和甘氨酸在水中的积分溶解热,及REBr3·nH2O(RE=La、Ce、Pr时,n=7;RE=Nd、Sm、Eu、Gd、Tb、Dy、Y时,n=6)在甘氨酸水溶液中的积分溶解热。用本研究设计的热化学循环求得上述10种REBr3·3Gly·3H2O配合物的标准摩尔生成焓,并计算出它们的晶格能。  相似文献   

9.
通过由Fe3(CO)12、RSH和Et3N所形成的[(μ-CO)(μ-RS)Fe2(CO)6]Et3NH于室温下分别与对或间苯二甲酰氯的原位反应,首次合成6个结构新颖的苯二甲酰基桥联铁硫配合物[(μ-RS)·Fe2(CO)6]2(μ-p-OCC6H4CO-p-μ)(R=Et,n-Bu,t-Bu)以及[(μ-RS)Fe2(CO)6]2(μ-m-OCC6H4CO-m-μ)(R=n-Pr,n-Bu,t-Bu)。经元素分析、IR光谱及1HNMR表征了它们的结构,并讨论了产物的生成过程。此外,还提出了合成对苯二甲酰氯的一种新方法。  相似文献   

10.
在乙腈介质中合成了苯并-12-冠-4(简称B-12-C-4)和单环己基-12-冠-4(简称Cy-12-C-4)的六种希土配合物:RE(NO3)3·B-12-C-4(RE=Pr,Gd,Yb,Lu),RE(NO3)3·Cy-12-C-4(RE=La,Lu)。研究了它们的IR及^1HNMR性质,并测定了四种单晶的结构,用INDO法计算了Lu(NO3)3·B-12-C-4,Lu(NO3)3·Cy-12-C  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.

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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.
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   

16.
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   

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.
The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.  相似文献   

19.
20.
设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。  相似文献   

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