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991.
992.
Vukadin M. Leovac Vladimir Divjaković Ana F. Petrović Nikolai V. Gerbeleu 《Monatshefte für Chemie / Chemical Monthly》1989,120(3):181-186
Summary The reaction of warmDMF solutions of Cu(II) perchlorate, 5-nitrosalicylaldehyde S-methylisothiosemicarbazone (H2
L) and piperidine (Pip) yielded the paramagnetic (eff=2.19 B.M.) Cu(L)Pip complex, whereL is the dianionic form of H2
L, formed as a result of deprotonation of the phenolic hydroxyl and NH2 group. Crystal data of the complex are: monoclinic P21,a=11.902(4),b=6.765(3),c=11.343(4)Å; =112.92°,V=841.20(8)Å3,M=400.9,Z=2,d
0=1.60 gcm–3,d
c
=1.58 gcm–3,F(000)=424. The structure was refined to a residualR=0.047. The copper(II) ion is coordinated in a square-planar arrangement by the piperidine nitrogen and the NNO set of donor atoms ofL.
Komplexe der Übergangsmetalle mit Thiosemicarbazid-Liganden, IV. Synthese und molekulare Struktur von 5-Nitrosalicylaldehyd-S-methylisothiosemicarbazonato-piperidin-kupfer(II)
Zusammenfassung Durch die Reaktion in warmenDMF-Lösungen von Cu(II) Perchlorat, 5-Nitrosalicylaldehyd-S-methylisothiosemicarbazon (H2 L) und Piperidin (Pip) wurde ein paramagnetischer Komplex (eff=2.19 B.M.) Cu(L)Pip erhalten, wobeiL nach doppelter Deprotonierung (NH2- und Phenolhydroxyl-Gruppe) als dianionische Form von H2 L vorliegt. Die kristallographischen Daten des Komplexes sind: monokline Raumgruppe P21,a=11.902(4),b=6.765(3),c=11.343(4)Å, =112.92°;V=841.20Å3,M=400.9,Z=2,d 0=1.60 gcm–3,d c =1.58 gcm–3,F(000)=424. Die struktur wurde bis zu einemR-Wert von 0.047 verfeinert. Die Koordination des Kupfers wird quadratisch-planar über den Piperidin-Stickstoff und die NNO-Donorhülle der Chelatliganden gebildet.相似文献
993.
The determination of nanometer thick layers of poly(methyl methacrylate) coated on to the surface of poly(ethylene terephthalate) film has been investigated by high resolution pyrolysis gas chromatography without sample pretreatment or modification of the instrumentation used. A good linear relationship was observed between the quantity of the characteristic pyrolysate and the thickness of the poly(methyl methacrylate) layer; the detection limit was sufficient to enable the quantitation of poly(methyl methacrylate)-to-poly(ethylene terephthalate) film thickness ratios of 1:20000 in composite materials. 相似文献
994.
热致液晶共聚酯酰胺/PET共混物的流变性能和原位增强特性 总被引:3,自引:1,他引:3
采用Instron3211型毛细管流变仪研究了PEA/PET共混物的流变性能,据此探讨共混物熔体的可纺性,讨论了共混物配比与复合纤维力学性能的关系,并且偏光显微镜,扫描电镜研究纤维的结构。结果表明,共混物的表观粘度低于PET的粘度,当PEA为10%,共混物的表观粘度达到最小值;且PEA含量低于10%时,共混物的可纺性即,表现出良好的原位增强效果。 相似文献
995.
Pseudoelement Compounds. VIII. [1]. On the Coordination Behaviour of Potential Ambidentate Aryl-cyanamidosulfonate Ligands Aryl-cyanamidosulfonates form with metal(II) ions (Co, Ni, Cu, Zn, Cd, Hg, Pd, Pt) complexes of the types MX2, [MX2L2], [MX2L4] and [MX4]2?. The ionic, potentially ambidentate ligand [RSO2NCN]? is monodentately coordinated via the terminal nitrogen atom and bidentately in a bridging function through the nitrile group end-on (equatorial) and one of the two sulfonyl oxygen atoms (axial). The new compounds are characterized by means of ir and uv-vis spectroscopy. In the case of [Ni(NCNSO2C6H4Me-4)2(py)4] the molecular and crystal structure was determined. 相似文献
996.
A. V. Kurkin V. V. Nesterov A. V. Karchava M. A. Yurovskaya 《Chemistry of Heterocyclic Compounds》2003,39(11):1466-1477
A new approach has been proposed to the synthesis of indole derivatives containing a chiral substituent at the nitrogen atom, comprizing Fischer indolization of phenylhydrazines with a chiral substituent at the -nitrogen atom. The initial hydrazines were obtained by the alkylation (Mitsunobu reaction applying optically active esters of lactic acid) of anilines containing an electron-accepting substituent at the amino group. Subsequent removal of the activating acceptor grouping was realized by nitrosation of the chiral secondary aniline followed by reduction of the corresponding N-nitroso compound. 相似文献
997.
Shu Ping XU* Huan Wen CHEN Ai Min YU Qin Han JIN Hua Ying LIAO Changchun R&D Center for Analytical Instruments Department of Chemistry Jilin University Changchun Key Laboratory for Supramolecular Structure Spectroscopy of Ministr 《中国化学快报》2002,13(7):660-661
In recent years, the determination of Cr (VI) has attracted great attention because of its toxicity to human, plants and animals1-5. Usually, in the industrial waste water, the concentration of Cr (VI) is relatively high and should be determined frequently. So, an accurate, quick, and convenient method for the measurement of Cr (VI) in environmental water, as well as in river, lake, sea and tap water, is of great importance. The method for determination of Cr (VI) by diphenylcarbazine … 相似文献
998.
6-氨基青霉烷酸在弱碱性阴离子树脂IRA67上的吸附研究 总被引:2,自引:0,他引:2
用静态法研究了6-氨基青霉烷酸在弱碱性阴离子交换树脂IRA67上的吸附行为.在溶液pH为8.0,6-APA起始浓度介子3.00mg/m1-20.00mg/ml条件下,测定了25℃时IRA67树脂的静态交换动力学曲线、吸附等温线,并求得了IRA67树脂的平衡速率常数及吸附等温线方程.分别用Langmuir型和Frendlich型方程对IRA67树脂吸附等温线进行线性回归拟合,结果表明,6-APA在IRA67树脂上的吸附更符合Langmuir型吸附. 相似文献
999.
E. U. Franck 《Journal of solution chemistry》1973,2(2-3):339-356
A survey is given of recent experimental results obtained from high-temperature, high-pressure investigations with water, aqueous solutions, and ionic fluids. Data on the static dielectric constant of water to 550°C and 5 kbar are given and discussed with respect to their relation to water structure. Infrared and Raman spectra of HDO in pure water have been obtained to 400°C and 4 kbar, which give information on hydrogen bonding. Xe–H2O and CO2–H2O mixtures were investigated in the infrared. Ni(II) and Cu(II) complexes were investigated by absorption spectroscopy in aqueous solutions of high chloride content to 350°C and 2–6 kbar. The gas-liquid critical point of ammonium chloride was found at 880°C and 1635 bars. This fluid appears to be predominantly ionic even in the critical region. The possibility of converting pure polar fluids such as ammonia and water into concentrated ionic solutions by self-ionization at very high pressures is mentioned.This paper was presented at the symposium, The Physical Chemistry of Aqueous Systems, held at the University of Pittsburgh, Pittsburgh, Pennsylvania, June 12–14, 1972, in honor of the 70th birthday of Professor H. S. Frank. 相似文献
1000.
A. G. Matveeva E. I. Matrosov Z. A. Starikova G. V. Bodrin S. V. Matveev P. V. Petrovskii E. E. Nifant’ev 《Russian Chemical Bulletin》2005,54(11):2519-2534
The trifunctional ligand, 2,6-bis(diphenylphosphorylmethyl)-4-methylphenol (L
2), forms complexes with cerium(III) nitrate having a ligand to metal ratio of 1: 1, 2: 1, and 3: 1. The structures of these complexes in the solid state and
in solution were studied by X-ray diffraction, IR and NMR (1H and 31P) spectroscopy, and conformational analysis (molecular mechanics). The 2: 1 complexes of L
2 with lanthanum(III) and neodymium(III) nitrates were synthesized and characterized. In all complexes, the neutral ligand is coordinated through both phosphoryl
oxygen atoms. The hydroxy oxygen atom is coordinated only in some complexes, and the hydrogen atom of the hydroxy group is
involved in hydrogen bonding. The compositions and structures of the resulting complexes depend on the method of synthesis
and the nature of solvent. The ligand was found to undergo easy inner-sphere oxidation. The structure of one of the transformation
products was established by X-ray diffraction. Unlike the coordinated ligand, the free ligand is very stable to oxidation.
Dedicated to Corresponding Member of the Russian Academy of Sciences T. A. Mastryukova.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2440–2454, November, 2005. 相似文献