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1.
周光明  盛蓉生 《分析化学》1995,23(9):1022-1027
本文在银胶活性基质上获得了Cu(Ⅱ)的中位-四(4-N-氰甲基吡啶)卟啉络合物Cu(Ⅱ)NACN的表面增强喇曼光谱光谱,并与其RRS光谱作了比较,讨论了PH值和Cu(Ⅱ)NACN的复合物的SERS光谱的影响,研究了小牛胸腺双链DNA及其变性DNA与Cu(Ⅱ)NACN的复合物的SERS光谱,指出Cu(Ⅱ)NACN是通过吡啶氮和卟啉核共同与银胶作用的,Cu(Ⅱ)NACN是斜向吸附在银表面上的,最佳PH  相似文献   

2.
合成了4个新型Ni-BDT配位化合物,BDT为具有9个S原子的杂戊烯,元素分析、IR谱、UV谱确定这4个新配合物的化学式分别为「(CH3)4N」2「Ni(C5S9(2」「(C2H5)4N」2·「Ni(C5S9)2」(2),「(C4H9)4N」2「Ni(C5S9)2」(3),「(C6H5)(CH5)3N」2「Ni(C5S9)2」(4),采用Ito法对配合物1的X射线粉末图进行了指标化,确定该晶体属单  相似文献   

3.
采用现场共聚焦显微喇曼光谱研究钴电极在碱性溶液中的氧化还原行为和生成物的喇曼光谱特征。研究结果表明:电位正向扫描时,在-0.64V左右Co氧化生成Co(OH)2和CoO,随着电位正移逐步生成Co3O4,在正电位区电极表面层主要是Co3O4,CoOOH和CoO2等;电位负向扫描时,电极由的高价含氧化合物相继还原为Co3O4和Co(OH)2,并最终还原为Co。由不同电位下的生成物的喇曼光谱可以看出;电  相似文献   

4.
用沉积银胶的银镜作活性载体,获得了中位-四-(4-N-乙氧羧甲基吡啶)卟啉络铜(Ⅱ)(Cu(Ⅱ)NEAE)、中位-四-(4-N-氰甲基吡啶)卟啉络酮(Ⅱ)(Cu(Ⅱ)NACN)的近红外富里叶变换-表面增强喇曼光谱(NIRFTSERS),对其谱峰位移作了归属,并与它们的可见激光表面增强共振喇曼光谱(SERRS)作了比较。  相似文献   

5.
合成了通式为α-M7-xHx[P2W15Mo2NbO62].xH2O]M=K^+,(CH3)4N^+,(C2H5)4N^+,(C4N9)4N^+]的4种盐。用IR,UV吸收光谱,极谱,183WNMR,XPS和XRD等方法对其进行了表征,确认三取代的位置在Dawson结构的同一“极位”。研究了取代W原子数目对183WNMR化学位移的影响,发现“极位”W原子的183WNMR化学位移平衡值与取代原子数目  相似文献   

6.
将Gly-GlyO,4,4'-联吡啶与Cu(NO3)2.H2O在二次水溶液中反应,合成出以4,4'-bpy为中继基,Cly-GlyO为螯环的新型双核铜配合物,经X射线单晶结构分析确定该配合物晶体的化学结构式为[(H2NCH2CONHCH2COO)Cu(OH)(C10H8N2)Cu(OH)(H2NCH2CONHCH2COO)].9H2O。晶体属P1空间群,晶胞参数α=1.1412nm,b=1.229  相似文献   

7.
本文介绍水杨配合与4-氨基-3,5-二乙基-1,2,4-三唑缩合而成对称三唑Schif碱(SAETZ)与氯化铜(CuCl2)形成一种新的配合物Cu(SAETZ)2(SAETZ=4-(邻羟苯基亚甲基)-亚胺-3,5-二乙基-1,2,4-三唑)。配合物的晶体结构表明,分子中两个偶氮甲碱的N原子及两个酚氧原子与中心Cu原子形成规则的平面配位结构。晶体属单斜晶系,空间群P21/n,a=8.688(2),b=9.314(1),c=16.515(4),β=94.34(2)。,V=1332.5(7)3,Z=2。  相似文献   

8.
标题化合物是FeCl3·6H2O和TPA·3HClO4(TPA= (C6H6N)3N) 在甲醇溶液中反应得到的橙色晶体。X-射线衍射测定了其单晶结构。结果表明,该晶体属单斜晶系, C2/c 空间群。化学式:C36 H36 Cl4Fe2N8O9, Mr = 978.22, a= 16.300(3), b=17.180 (3), c= 16.582(3) , β= 111.75(3)°, V= 4131 3, Z= 4, Dc= 1.299g/cm 3, μ(MoKα) = 8.43 cm - 1, 4211 个可观测衍射点,R= 0.043, RW = 0.049。分子中氧原子桥联两个铁(Ⅲ) 原子, TPA 上的 4 个氮原子和 1 个氯离子分别占据铁(Ⅲ)原子的其余5 个配位位置, 形成6 配位畸变8 面体构型。  相似文献   

9.
测量了不同温度下CCl4液芯光纤喇曼光谱强度,实验结果表明,光谱强度随着温度的变化存在着一个极大值,对影响光纤喇曼光谱强度的几个主要因素进行了估算,理论与实验结果符合较好。  相似文献   

10.
合成了2个新的希土冠醚配合物Ln(NO3)3·C26H38N2O4(Ln=La、Ce;C26H38N2O4=1,7,10,16-四氧-4,13-二氮杂-N,N′-二苄基环十八烷)。通过元素分析,红外光谱,拉曼光谱及其1H核磁共振谱进行表征。用四圆衍射仪测定了La(NO3)3·C26H38N2O4·CH3CN的晶体结构。晶体属三斜晶系,P1空间群,晶胞参数:a=1.2869(4)nm,b=1.5868(6)nm,c=0.9147(2)nm;α=101.89(2)°,β=105.38(2)°,γ=71.96(3)°;Z=2。dcald.=1.58g·cm-3,μ(MoKα)=13.25cm-1。中心镧离子与冠醚配体中的4个氧原子和2个氮原子配位,3个硝酸根中的6个氧原子也与La3+配位,形成配位数为12的配合物。  相似文献   

11.
An organic-inorganic molecular hybrid containing the Dawson polyoxometalate, ((C(4)H(9))(4)N)(5)H[P(2)V(3)W(15)O(59)(OCH(2))(3)CNHCOC(15)H(31)], was synthesized and its surfactant-like amphiphilic properties, represented by the formation of bilayer vesicles, were studied in polar solvents. The vesicle size decreases with both decreasing hybrid concentration and with increasing polarity of the solvent, independently. The self-assembly behavior of this hybrid can be controlled by introducing different counterions into the acetonitrile solutions. The addition of ZnCl(2) and NaI can cause a gradual decrease and increase of vesicular sizes, respectively. Tetraalkylammonium bromide is found to disassemble the vesicle assemblies. Moreover, the original counterions of the hybrid can be replaced with protons, resulting in pH-dependent formation of vesicles in aqueous solutions. The hybrid surfactant can further form micro-needle structures in aqueous solutions upon addition of Ca(2+) ions.  相似文献   

12.
Cretich M  Chiari M  Pirri G  Crippa A 《Electrophoresis》2005,26(10):1913-1919
Adsorbed polymers are widely used to suppress electroosmotic flow (EOF) in capillary electrophoresis (CE). Polymeric coatings, physisorbed onto the surface of the capillary wall, are often unstable under harsh conditions. This can be attributed to the reversible nature of the coating which becomes apparent when the adsorbed layer competes with a second species in the electrophoresis buffer solution for attachment/interaction with the capillary surface. In an effort to overcome the problem of coating instability, trimethoxysilane-modified polydimethylacrylamide was synthesized. This copolymer rapidly adsorbs on the wall from ultradilute aqueous solutions. After incubation at a temperature of 60 degrees C silyl groups, which extend from the polymer backbone, form condensation bonds with the silanols on the capillary surface. This enables subsequent formation of strong covalent bonds between the copolymer and the capillary wall. In this research, we establish that physisorption of polymer chains to the surface is essential for close alignment of surface and polymer silane groups which facilitates the formation of covalent bonds.  相似文献   

13.
Textbooks of inorganic chemistry describe the formation of adducts by coordination of an electron donor to an electron acceptor, often using the amine-boranes, X3N → BY3, as examples. In the Lewis (electron dot) formulas of the compounds, the dative bond in H 3 N → BH3 and the covalent bond in H3C?CH3 are both represented by a shared electron pair. In the simple molecular orbital or valence bond models the wave functions of both electron pairs would be constructed in the same manner from the appropriate sp3 type atomic orbitals on the bonded atoms; the difference between the covalent and the dative bond becomes apparent only after the orbital coefficients have been analyzed. This may be the reason why many structural chemists seem reluctant to distinguish between the two types of bonds. The object of this article is to remind the reader that the physiocochemical properties of covalent and dative bonds may be – and often are – quite different, and to show that a distinction between the two provides a basis for understanding the structures of a wide range of main group metal compounds.  相似文献   

14.
The viscoelastic properties of semidilute mixed aqueous solutions of oleyl amidopropylbetaine and sodium dodecylbenzene sulfonate are studied in the temperature range of 20–40°C. It is shown that, at 20°C, the solution viscosity can be as high as 390 (Pa s), which is related to the formation of a network of entanglements of long cylindrical micelles of surfactants. It is revealed that, upon heating, the viscosity and relaxation time of the system decrease, while the contour length of cylindrical micelles decreases consider-ably. It is shown that this susceptibility of viscoelastic surfactant solutions to temperature is due to the low energy of break, which is much lower than the energy of covalent bonds.  相似文献   

15.
The structure and hydrogen bonding of water in aqueous solutions of various surfactants were analyzed using the contours of the O-H stretching in the polarized Raman spectra. From the relative intensity of the collective band (C value) corresponding to a long-range coupling of the O-H stretching in the aqueous surfactant solutions, the number of hydrogen bonds disrupted due to the presence of one surfactant molecule (N(corr) value) was evaluated. The N(corr) value for decylsulfobetaine was slightly negative, whereas those for ordinary ionic surfactants such as sodium dodecylsulfate and dodecyltrimethylammonium chloride were large positive values. Furthermore, the N(corr) for carboxybetaine surfactant was a small positive value. These results suggest that zwitterionic surfactants do not disturb the hydrogen-bonded network structure of water significantly, probably due to the counteraction of the electrostriction effect by the proximity between the anionic and cationic groups.  相似文献   

16.
We have obtained quantitative information about the hydrogen bond strength in pure water and in dilute aqueous solutions of methanol by analyzing the temperature dependence of Raman spectra of the decoupled OD stretch from 21 to 160 degrees C with the hydrogen bond energy dispersion method. A minimum at 2440 cm(-1) assigned to strong icelike hydrogen bonds and a maximum at 2650 cm(-1) due to maximally (but not completely) broken hydrogen bonds result in all cases. The energy of the minimum decreases upon addition of methanol due to formation of stronger water-methanol hydrogen bonds, whereas the energy of the maximum increases because water hydrogen atoms in the vicinity of the methyl group might participate in "more broken" hydrogen bonds than in bulk water.  相似文献   

17.
A covalently attached sandwich structure between layers and particles has been fabricated from z.sbnd;COOH-containing copolymer latex particles and z.sbnd;N(2)(+)-containing polymers by self-assembly combined with a UV irradiation technique. The ionic bonds involving the layers and particles change to covalent bonds under UV irradiation and the sandwich structure become very stable toward polar organic solvents and electrolyte aqueous solutions.  相似文献   

18.
聚-4-重氮基苯乙烯(PDS)在碱性水溶液下通过与Na2SO3反应,制备了聚-4-偶氮磺酸基苯乙烯(PDSS).作为负离子聚电解质PDSS能与四-(三甲氨基苯基)-卟啉(TTMAP)通过离子相互作用进行层-层自组装.光照下该组装膜中的离子键转变为共价键,结果是组装膜对极性溶剂和盐水溶液变为非常稳定,从而能直接在KCl水溶液中测定其光电流.结果表明,该组装膜具有良好的光电转换性质.  相似文献   

19.
The asymmetric unit of the title polymeric complex, [HgBr(C6H4NO2)]n or HgBr(nic), contains mercury coordinated via two Br atoms [Hg—Br = 2.6528 (9) and 2.6468 (9) Å], two carboxyl­ate O atoms, which form a characteristic four‐membered chelate ring [Hg—O = 2.353 (6) and 2.478 (7) Å], and an N atom [Hg—N = 2.265 (5) Å], in the form of a very irregular (3+2)‐coordination polyhedron. The pronounced irregularity of the effective Hg (3+2)‐coordination is a result of the rigid stereochemistry of the nicotinate ligand. According to the covalent and van der Waals radii criteria, the strongest bonds are Hg—Br and Hg—N. These covalent interactions form a two‐dimensional poly­mer. The puckered planes are connected by van der Waals interactions, and there are only two intermolecular C—H⋯O hydrogen bonds [3.428 (10) and 3.170 (10) Å].  相似文献   

20.
Only two silyldichloramines, (C6H5)3SiNCl2 and (CH3)3SiNCl2, have been reported in the literature. The synthesis of the former was successfully repeated, and its structure was established by single-crystal X-ray diffraction and vibrational spectroscopy. Attempts to prepare (CH3)3SiNCl2 were unsuccessful; however, a new trialkylsilyldichloramine, t-BuMe2Si-NCl2, was prepared and characterized by Raman and multinuclear NMR spectroscopy. The reaction of t-BuMe2SiNCl2 with (CH3)4NF in CHF3 solution at -78 degrees C, followed by removal of all volatile products at -30 degrees C, produced the expected t-BuMe2SiF byproduct and a white solid consisting of NCl3 absorbed on Me4NCl. The NCl3 could be reversibly desorbed from the substrate and was identified as a neat liquid at room temperature by Raman spectroscopy. The observed final reaction products are consistent with the formation of an unstable N(CH3)4+NCl2- intermediate which decomposes to N(CH3)4+Cl- and NCl molecules which can dimerize to N2Cl2. Theoretical calculations confirm that NCl2- can readily lose Cl- and that N2Cl2 also possesses a low barrier toward loss of N2 to give chlorine atoms and, thus, can account for the formation of NCl3.  相似文献   

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