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981.
J. Legendziewicz K. Bukietyńska G. Oczko S. Ernst B. Jeżowska-Trzebiatowska 《Chemical physics letters》1980,73(3):576-581
Absorption spectra of holmium nitrate in MFA and DMF have been measured in the range 8000–42000 cm?1. The τλ parameters were evaluated from the experimental oscillator strengths using the Judd equation. For Ho(NO3)3 in DMF a considerable increase in τ2 was observed, suggesting the existence of inner-sphere species in this system. This suggestion was verified by ultrasonic absorption and conductivity measurements. 相似文献
982.
Katarzyna Kaszyńska Ewa Banachowicz Genowefa Ślósarek Adrian Morawiec Iwona Gawrońska Jan Barciszewski 《Journal of solution chemistry》2002,31(12):987-993
We analyze the structure of napin (BngNAP1), a storage protein (m.w. 14.5 kDa) from Brassica napus. On the basis of the results of 1H NMR spectroscopy and dynamic light scattering (DLS) studies, the overall shape and secondary structure of the molecule are estimated. 相似文献
983.
Tomohisa?Yamaguchi Keisuke?Kimura Akira?Tsuchida Tsuneo?OkuboEmail author Mitsuhiro?Matsumoto 《Colloid and polymer science》2005,283(10):1123-1130
Macroscopic and microscopic dissipative structural patterns formed in the course of drying the fractionated and monodisperse bentonite particles (plate-like in their shape) in aqueous deionized suspension and in the presence of NaCl have been studied on a cover glass. The patterns coexisted with the broad ring of the hill accumulated with the particles and with the round hills are formed around the outside edges of the film and in the center, respectively, in the macroscopic scale. By the addition of NaCl the pattern shifts from the broad ring to the round hill in the center. The spoke-like cracks, which have been observed for the suspensions of the spherical particles so often hitherto, are not observed at all for the bentonite suspensions. The characteristic convection flow of the particles and the interactions among the particles and substrate are important for the macroscopic pattern formation. Wrinkled, branch-like and/or star-like fractal patterns are observed in the microscopic scale. These patterns are determined mainly by the electrostatic and polar interactions between the particles and/or between the particle and the substrate in the course of drying. 相似文献
984.
Jing?Zhou Yuqi?Liu Liming?Tang Xinchen?Teng Ning?Tang Zhongxian?HuangEmail author 《中国科学B辑(英文版)》2003,46(1):64-74
Two mutants of the zinc finger protein, ZNF191 (243–368) I323W and R327W, are successfully obtained by site-directed mutagenesis.
The fluorescence spectrum is used to study the interaction between these two mutants and the oligonucleotides. The influence
of the mutation on the interaction has been studied using ethidium bromide (EB) as the fluorescence probe. The binding constants
of the I323W-DNA and R327W-DNA have been calculated and the possible binding models have been discussed. 相似文献
985.
Centrosymmetric linear [Ar-H-Ar]+ and asymmetric linear [Ar---Ar-H]+ are two stable configurations of [Ar2H]+. Based on the global potential energy surface of [Ar2H]+ provided by our group recently, we calculated the vibrational spectra of [Ar---Ar-H]+ with total angular momentum J = 0 by time-dependent quantum mechanical method, and the influence of quantum tunneling effect on vibrational spectra was
found. With the help of the observation on the eigenstate functions and the modified potential energy surface, assignments
were made to the spectra. The strong coupling between the excited bending mode of [Ar-H-Ar]+ and the vibrational states of [Ar---Ar-H]+ was discussed. 相似文献
986.
987.
Danuta M. Czakis-Sulikowska Joanna Radwańska-Doczekalska Teresa Miazek 《Monatshefte für Chemie / Chemical Monthly》1982,113(6-7):827-835
4,4-Dipyridyl and 2,2-dipyridyl complexes of rare-earth perchlorates of the formulaLn(4-dipy)8(ClO4)3HClO4 · 4H2O (Ln=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu, Y, 4-dipy=4,4-dipyridyl) andLn(2-dipy)3(ClO4)3 · 6H2O (Ln=Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu, Y, 2-dipy = 2,2-dipyridyl) have been synthesized. The IR spectra of these compounds and other physical properties are discussed.
4,4-Dipyridyl- und 2,2-Dipyridylkomplexe von Seltenerdmetallperchloraten
Zusammenfassung Es wurden 4,4-Dipyridylkomplexe des TypsLn(4-dipy)8(ClO4)3HClO4 · · 4 H2O mitLn=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu, Y und 2,2-Dipyridylkomplexe des TypsLn(2-dipy)3(ClO4)3 · 6 H2O mitLn=Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu und Y dargestellt. Die IR-Spektren und andere physikalische Eigenschaften werden diskutiert.相似文献
988.
Pre-column labelling techniques are described for the determination of S-carboxymethyl-L-cysteine (CMC) and its metabolites in urine and plasma samples by high-performance liquid chromatography (HPLC) without prior extraction. All substances containing an amino group were converted into fluorescent fluorenylmethyl derivatives with 9-fluorenylmethyloxycarbonyl chloride (FMOC). Deaminated or N-acetylated carbocysteine metabolites were coupled with 1-pyrenyldiazomethane (PDAM) to give fluorescent PDAM esters. Similar results were obtained with the two commercially available and stable diazomethane derivatives PDAM and 9-anthryldiazomethane (ADAM). Following double derivatization with PDAM and FMOC, in a single chromatographic run with two fluorescence detectors connected in series, amines and amino(carboxylic) acids could be detected by their FMOC residues and, simultaneously, carboxylic acids were detected as fluorescent PDAM esters. The (R) and (S) enantiomers of the sulphoxides of CMC, of methylcysteine and of N-acetyl CMC were separated, although the reversed-phase HPLC system did not contain a chiral additive or stationary phase designed for the separation of enantiomers. The methods do not include liquid extraction steps and can therefore be performed either manually or automatically using an HPLC autosampler. These methods were used for the investigation of a disputed pharmacogenetic polymorphism of S-oxidation of CMC in humans, which until now has most often been studied using paper chromatography. The described techniques were applied to the determination of CMC and its metabolites in human urine and plasma samples. 相似文献
989.
Maria Grzegozek Marian Wo
niak Andrzej Baraski Henk C. Van Der Plas 《Journal of heterocyclic chemistry》1991,28(4):1075-1077
A number of 2-X-3-nitro-1,8-naphthyridines (X= H,D,OH,Cl,NH2, OEt) react with the anion of chloromethyl phenyl sulfone exclusively into 2-X-3-nitro-4-(phenylsulfonylmethyl)-1,8-naphthyridines in high yield. The reaction is found by quantum chemical calculations to be controlled by the interactions of the HOMO of the nucleophile with the LUMO of the substrate, and not by charge. 相似文献
990.
The reaction process between CuSO4 and excess Cu2S in the temperature range 650–750 K was investigated by methods of thermal analysis and by studying the phase contentss of the products as a function of the fractional conversion. The reaction proceeds in three steps, with Cu2S and a new phase described by the formula Cu2SO2 as intermediates. This new phase is liquid under the conditions of the reaction. The final product of the reaction is a defective crystalline Cu2O.
Zusammenfassung Der Verlauf der Reaktion zwischen CuSO4 und überschüssigem Cu2S im Temperaturbereich von 650–750 K wurde mittels thermoanalytischer Methoden und durch Ermittlung der Phasenzusammensetzung in AbhÄngigkeit von der Konversion untersucht. Die Reaktion verlÄuft in drei Schritten mit Cu2S und einer neuen Phase der Zusammensetzung Cu2SO2 als Zwischenproduke. Die neue Phase ist unter den Reaktionsbedingungen eine Flüssigkeit. Endprodukt der Reaktion ist nicht völlig kristallines Cu2O.
CuSO4 Cu2S 650–750 K . Cu2S , Cu2SO2 . Cu2O .相似文献