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11.
Summary A flow-through two electrode wall-jet cell with a platinum measuring electrode and a cell volume of 20 nl has been designed and evaluated. It has been used to detect phenols by reversed phase liquid chromatography using short micro bore columns. The linear dynamic range between the measured current and the concentration is greater than 103 (1.5×10–7–5×10–4 mol/l) and the minimum analyzable amount was found to be 10 pg for pyrocatechol. A negligible broadening in the detector permits the use of micro columns down to 0.5 mm internal diameter, packed with 5 m particles, without any substantial distortion of eluted zones.Presented at the 14th International Symposium on Chromatography London, September, 1982 相似文献
12.
2,2'-Biphenanthroline (2,2'-biphen) formed from 1,10-phenanthroline when a new two-dimensional layered vanadium oxide metal coordination complex, [(2,2'-biphen)Co]V3O8.5, which contains novel 4,8,10-net sheets, was hydrothermally synthesized. 相似文献
13.
多相催化反应原位红外系统及其应用 总被引:1,自引:0,他引:1
设计和建立了一套能耐高温的用于多相催化反应研究的原位红外系统,反应温度从室温到1150K,系统真空为1.0*10^5-1.0-10^-4Pa,红外光谱检测范围为4800-200cm^-1。此系统扩展了原仪器的功能,提高了仪器利用率和效率。 相似文献
14.
在硫酸钡微晶对毛细管内壁改性的基础上,系统制备了甲基环糊精与不同混合固定液的毛细管色谱柱,从柱的分离选择性,惰性,柱效和分析准确性等方面作了较为系统的研究,并对环糊精的分离机理作了初步探索。 相似文献
15.
In this work, the surface properties of novel sugar-containing polymers, α-allyl glucoside (AG)/acrylonitrile (AN)copolymers, were studied by contact angle, protein adsorption and cell adhesion measurements. It was found that the contactangle of the copolymer films decreased from 68° to 30° with the increase of AG content in the copolymer. The adsorptionamount of bovine serum albumin (BSA) and the adhesive macrophage onto the film surface also decreased significantly withincreasing α-allyl glucoside content from 0 to 42 wt% in the copolymer. These preliminary results reveal that both thehydrophilicity and the biocompatibility of polyacrylonitrile-based membranes could be improved by copolymerizing acrylonitrile with vinyl carbohydrates. 相似文献
16.
Ozeki H Nomoto A Ogawa K Kobuke Y Murakami M Hosoda K Ohtani M Nakashima S Miyasaka H Okada T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(24):6393-6401
We synthesized special-pair/electron-acceptor systems consisting of a complementary slipped cofacial dimer of imidazolyl-substituted zinc porphyrin, bearing pyromellitdiimide as the electron acceptor. In the case of the dimer, the first and second oxidation potentials were split into a total of four peaks in the differential pulse voltammetry measurement. Furthermore, the shift values of the first oxidation potentials obtained by changing the solvent polarity for the dimer were almost half of those observed for the monomer. These results indicate that the radical cation is delocalized over the whole pi system of the dimer. Time-resolved transient absorption measurements revealed that, relative to the corresponding monomer, the dimer accelerated the charge separation rate, but decelerated the charge recombination rate. The smaller reorganization energy of the slipped cofacial dimer relative to that of the monomeric system demonstrates the significance of the special-pair arrangement for efficient charge separation in photosynthesis. 相似文献
17.
铜(II)-5-取代邻菲啰啉-二氧四胺大环三元体系的稳定性研究 总被引:1,自引:0,他引:1
The stability of copper (Ⅱ)-13-(2'-Hydroxy-3',5'-substituted benzyl)-1,4,8,11-tetraazacyclotetradecane-12, 14-dione(RTADO-14) binary complex compounds and of copper (Ⅱ)-5-substituted-1,10-phenanthrolines(R'TADO)-RTADO-14 ternary complex compounds was studied by means of pH titration method at 25.0±0.1 ℃ and I=0.1mol?dm-3KNO3. The formation constants of binary and ternary complexes were obtained. The structures of the binary and ternary complxes and the effects fo substituents on macrocyclic ligands and on R'Phen were also discussed. 相似文献
18.
CONVERSION OF METHANE AND CARBON DIOXIDE TO AROMATICS OVER CHROMIUM-BASED CATALYSTS:SELECTIVITY AND YIELD OF MAIN PRODUCTS
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在840℃,0.5MPa,CH4/CO2摩尔比为1.4,接触时间(W/F)为0.79h·g·L-l的条件下,甲烷和二氧化碳在7.5wt%Cr/5.0wt%Na/SiO2催化剂上共活化得到了4.8%的C2选择性,48.7%的芳烃选择性及1.9%的芳烃收率。在钠修饰的铬基催化剂上,成功地一步实现了CH4和CO2转化为乙烯及中间物乙烯聚合为芳烃的过程 相似文献
19.
程序涂渍柱“柱效能程序效应”的研究 总被引:1,自引:0,他引:1
本文从理论上给出程序柱“柱效能程序效应”的概念并导出了函数关系式,通过计算机可计算柱效能程序效应与柱内各变量之间的关系,实践证明实验数据的变化趋势与理论数据相符。 相似文献
20.
Ni ZH Kou HZ Zheng L Zhao YH Zhang LF Wang RJ Cui AL Sato O 《Inorganic chemistry》2005,44(13):4728-4736
Two new cyano-bridged heterobinuclear complexes, [Mn(II)(phen)2Cl][Fe(III)(bpb)(CN)2] x 0.5CH3CH2OH x 1.5H2O (1) and [Mn(II)(phen)2Cl][Cr(III)(bpb)(CN)2] x 2H2O (2) [phen = 1,10-phenanthroline; bpb(2-) = 1,2-bis(pyridine-2-carboxamido)benzenate], and four novel azido-bridged Mn(II) dimeric complexes, [Mn2(phen)4(mu(1,1)-N3)2][M(III)(bpb)(CN)2]2 x H2O [M = Fe (3), Cr (4), Co (5)] and [Mn2(phen)4(mu(1,3)-N3)(N3)2]BPh4 x 0.5H2O (6), have been synthesized and characterized by single-crystal X-ray diffraction analysis and magnetic studies. Complexes 1 and 2 comprise [Mn(phen)2Cl]+ and [M(bpb)(CN)2]- units connected by one cyano ligand of [M(bpb)(CN)2]-. Complexes 3-5 are doubly end-on (EO) azido-bridged Mn(II) binuclear complexes with two [M(bpb)(CN)2]- molecules acting as charge-compensating anions. However, the Mn(II) ions in complex 6 are linked by a single end-to-end (EE) azido bridging ligand with one large free BPh4(-) group as the charge-balancing anion. The magnetic coupling between Mn(II) and Fe(III) or Cr(III) in complexes 1 and 2 was found to be antiferromagnetic with J(MnFe) = -2.68(3) cm(-1) and J(MnCr) = -4.55(1) cm(-1) on the basis of the Hamiltonian H = -JS(Mn)S(M) (M = Fe or Cr). The magnetic interactions between two Mn(II) ions in 3-5 are ferromagnetic in nature with the magnetic coupling constants of 1.15(3), 1.05(2), and 1.27(2) cm(-1) (H = -JS(Mn1)S(Mn2)), respectively. The single EE azido-bridged dimeric complex 6 manifests antiferromagnetic interaction with J = -2.29(4) cm(-1) (H = -JS(Mn1)S(Mn2)). Magneto-structural correlationship on the EO azido-bridged Mn(II) dimers has been investigated. 相似文献