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1.
建立了基于化学平衡理论模型以及凝胶过滤色谱(GFC)-电感耦合等离子体质谱(ICPMS)联用技术的高分子聚合物-金属配合物稳定常数、平均配位数测定新方法。以聚乙烯亚胺(PEI)和Cu2+为例,对形成的PEI-Cu配合物稳定常数、平均配位数进行测定,以0.02 mol·L-1 HAc-NaAc为流动相,凝胶色谱柱分离大分子PEI-Cu配合物以及Cu的小分子配合物、游离态离子,最后用ICPMS测定不同形态金属元素的浓度;利用建立的化学平衡理论模型,计算PEI与金属离子形成配合物的稳定常数、平均配位数,测得25℃,pH4.1~5.3时,PEI-Cu配合物稳定常数为109.6~1010.7,平均配位数为1.0~1.3。建立的在线分离、测定方法具有快速、准确的特点,为高分子聚合物-金属配合物的研究提供新的技术手段。  相似文献   

2.
运用pH电位滴定法,在25±0.1℃ T,I=0.1(KNO3)条件下,研究了Cu(Ⅱ)与三吡啶胺(L1)和队(2'-羟基苄基)-二乙二胺(HL2)的配位行为。结果表明,L1以二齿的形式和Cu(Ⅱ)形成稳定的2:1(L:M)配合物。其配位水分子的离解常数pKa为7.54.对于HL2,三个氮原子和酚氧负离子与Cu(Ⅱ)配位,酚羟基离解常数pKa为4.44.在25±0.1℃,I=0.1(KNO相似文献   

3.
本文采用pH法,在25.0±0.1℃,I=0.1mol·dm-3KNO3存在条件下,测定了铜(Ⅱ)-1,4,7,10-四氮杂环十三烷-11,13-二酮-α-氨基酸(5-取代邻菲罗啉)三元配合物的稳定常数,探讨了大环多胺配体与金属离子的配位能力、配位方式、及其在水溶液中铜(Ⅱ)配合物的稳定性,同时也研究了5-取代邻菲罗啉与铜(Ⅱ)之间的d-p反馈π键、取代基的Hammett诱导效应对三元配合物稳定性的影响。  相似文献   

4.
在二甲亚砜-水混合溶剂中用pH电位法测定了T4的质子化常数以及与五种希土离子(Pr3+、Eu3+、Gd3+、Tb3+、Yb3+)生成配合物的稳定常数。体系中主要生成110型配合物,紫外吸收光谱,HNMR表明,在较低pH值,T4通过羧基与希土配位,pH较高时,氨基也相继配位。配位键以离子性为主,荧光光谱表明,T4对中心希土离子的荧光有猝灭作用。  相似文献   

5.
近年来,有关过渡金属离子冠醚配合物的研究虽有一些报道,但这些研究所涉及的配体大多数是单取代苯并冠醚,对双取代苯并冠醚配位的研究则很少[1].为了进一步弄清取代冠醚对过渡金属配位性能的影响,我们研究了混合双取代的苯并-15-冠-5,根据文献[2,3]合成了4′-溴-5′-硝基苯并-15-冠-5,并制得了一种新的配合物FeCl3·L,经性质证明此配合物是1:1型非溶剂合、不含水的固体配合物,其三个Cl-离子位丁配合物的外界.  相似文献   

6.
合成了N(1)取代5-氟尿嘧啶乙酸、5-氟尿嘧啶丙酸与铜(Ⅱ)、钴(Ⅱ)、镍(Ⅱ)和锰(Ⅱ)的十种金属配合物。通过元素分析、差热-热重分析确定了它们的化学组成,并对这些化合物进行了红外光谱、氢核磁共振谱,电子光谱的表征。讨论了各配合物中金属离子与配体的配位状态。在Cu(Ⅱ)配合物中,Cu(Ⅱ)是与配体的N3原子和C4上的羰基氧原子配位,其他金属配合物中,金属离子是与配体的C2的羰基氧原子和羧基配位。  相似文献   

7.
L-苏糖酸与金属离子的配位性能   总被引:9,自引:0,他引:9  
本文在298K、I=0.1 mol·L-1 KNO3条件下测定了L-苏糖酸的质子化常数及其与钙(Ⅱ)、镉(Ⅱ)、锌(Ⅱ)、钴(Ⅱ)、铜(Ⅱ)二元配合物的生成常数。L-苏糖酸的质子化常数与葡萄糖酸的质子化常数一致,pKa为3.56。其与金属离子的配位方式也与葡萄糖酸一致,但其二元配合物的生成常数明显比葡萄糖酸大。L-苏糖酸与不同金属离子作用的方式不同,与钙(Ⅱ)、镉(Ⅱ)、锌(Ⅱ)、钴(Ⅱ)配位时不解离出醇羟基质子,而与铜(Ⅱ)配位时则  相似文献   

8.
用分光光度法研究了2.6-二乙酰基吡啶缩二(氨基疏脲)与 Cu2+,Co2+,Ni2+,Zn2+的配位反应,用作图法和自编的LEMIT-S程序计算了配合物的组成,摩尔吸光系数和稳定常数,两法所得的结果基本一致,结果表明,在乙醇中Cu2+与配体daptsc形成Cu2(daptsc)和Cu(daptsc),二者在溶液中共存,而Cu2+在DMF中仅生成1:1配合物,其它金属离子在两种溶剂中均形成1:1型。在两种溶剂中lgβ11的顺序为:Zn > Cu > Ni > Co.  相似文献   

9.
本文合成了2个新的含乙酰氧肟酸配体的席夫碱钒配合物,[VL1(HAHA)](1)和[VOL2(AHA)](2),其中L1N,N’-二(5-甲基水杨基)乙烷-1,2-二胺的二价阴离子,L2为2-{[2-(2-羟乙基氨基)乙亚胺基]甲基}-6-甲基苯酚的一价阴离子,HAHA和AHA分别为乙酰氧肟酸的一价和二价阴离子,通过物理-化学方法以及单晶X-射线衍射表征了它们的结构。在每个化合物中,V原子都采取八面体配位构型。本文还研究了配合物的热稳定性以及其对幽门螺旋杆菌脲酶的抑制活性。在浓度为100μmol·L-1时,配合物12对脲酶的抑制率分别为37.2%和81.5%,其中配合物2的IC50值为21.5μmol·L-1。分子对接研究表明配合物2与脲酶活性中心存在有效的作用力。  相似文献   

10.
过渡金属席夫碱配合物的稳定性及其杀菌活性   总被引:22,自引:0,他引:22  
在25±0.1℃,I=0.1 mol·L-1 KNO3条件下,应用pH法测定了甲酰基甲酸缩氨基硫脲(A配体,缩写H2FFTSC),甘氨酰甘氨酸(B配体,缩写HGG)的质子化常数,它们与锰(Ⅱ)、钴(Ⅱ)、镍(Ⅱ)、铜(Ⅱ)和锌(Ⅱ)的二元配合物以及过渡金属(Ⅱ)-甲酰基甲酸缩氨基硫脲-甘氨酰甘氨酸三元配合物稳定常数,讨论了过渡金属席夫碱配合物的杀菌活性与其稳定性之间的关系,对杀菌机理提出了一些看法。  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.
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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