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961.
Colloid and Polymer Science - 相似文献
962.
Verdejo B Aguilar J Doménech A Miranda C Navarro P Jiménez HR Soriano C García-España E 《Chemical communications (Cambridge, England)》2005,(24):3086-3088
L-glutamate and L-aspartate selectivity is achieved by the action of two Cu2+ metal ions rightly disposed in a cyclophane-type macrocyclic framework; electrochemical sensing of glutamate has been achieved by adsorption of the copper complexes on graphite electrodes. 相似文献
963.
V. R. Polishchuk L. A. Leites E. I. Mysov A. F. Aérov E. M. Kagramanova 《Russian Chemical Bulletin》1992,41(2):358-359
Trifluoroacetic acid adds to 2,3-difluorobicyclohepta[2.2.1]diene-2,5 at the FC=CF bond to give mainly the cis-exo adduct.A. N. Nesmeyanov Institute of Organometallic Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 2, pp. 450–452, February, 1992. 相似文献
964.
N. V. Gérbéléu V. B. Arion Yu. A. Simonov V. E. Zavodnik K. I. Turté S. S. Stavrov A. A. Pasynskii O. G. Ellert D. I. Grédinaru M. S. Byrke 《Theoretical and Experimental Chemistry》1991,27(3):327-332
Sodium acetylacetonate reacts with S-metliylisothiosemicarbazidium nitrate and Fe(NO3)3 · 9H2O in ethanol to make [Fe(HL)NO]NO3, in which H3L is bis(S-methyl-isothiosemicarbazone)-2,4-puntandione. The [Fe(HL)NO]+ cation has a square pyramidal structure with the HL2- arranged around the central ion in the basal plane and the nitrogen atom of the NO group in the apical position, with the iron atom diverging from the plane of the base of the pyramid by 0.477 Å. The FeN0 moiety has a linear structure (FeNO = l72.7°). XRD, IR, and Mössbauer spectroscopy have been combined with calculations on the electronic structure to demonstrate that the Fe-NO bond is covalent.Chemical Institute, Academy of Sciences of Moldavian SSR. Applied Physics Institute, Academy of Sciences of the Moldavian SSR. Kishinev. Institute of Crystallography, Academy of Sciences of the USSR. Kurnakov Institute for General and Inorganic Chemistry, Academy of Sciences of the USSR, Moscow. Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 27, No, 3, pp. 376–381, May–June, 1991. Original article submitted February 18, 1991. 相似文献
965.
O. Kóréh K. Torkos M. Bashir Mahara J. Borossay 《Journal of Radioanalytical and Nuclear Chemistry》1998,235(1-2):47-52
There is often a need to calculate isotopic uranium activities from total uranium mass or gamma spectrometry measurement data.
This calculation is based on a model of the relationship of the234U activity to that of235U since both are enriched together in the normal gaseous diffusion enrichment process. This paper presents equations for calculating
these activities that have been developed from several sources of data. These equations have been used for several characterization
studies and have produced very good results when compared to results from actual isotopic uranium analyses. However, because
the variability in the model causes significant uncertainty in the calculated results, alpha-spectrometry is recommended for
critical applications. 相似文献
966.
Pedro A. Fernandes Elsa S. Henriques Vineet Pande Maria. J. Ramos Ana R. R. Maia André A. S. Almeida Bruno F. B. Silva Carla M. S. Ribeiro César F. B. Ribeiro David S. M. Ribeiro Diana A. P. Fonseca Eva M. S. Cunha Filipe R. N. C. Maia Joana A. A. Pereira João P. G. Pacheco Joaquim A. A. D. Ferreira Liliana R. C. Matos Manuel A. B. P. Pinto Maria C. S. Borges Paulo J. C. R. Magalhães Pedro F. R. D. Teixeira Pedro N. B. C. Veloso Ricarte J. F. Ferreira Sandro S. Gomes Tiago F. Barros Tiago S. J. T. Selão Virgínia M. M. C. Fernandes 《Theoretical chemistry accounts》2005,113(4):197-204
We present a series of new inhibitors of the association between nuclear factor kappa B (NF-B) and the corresponding B site in DNA. They were designed using the lead compound 15-deoxy-12,14 -prostaglandin J2 (PGJ2), which is a natural product with demonstrated inhibitory efficiency for this system. First, the binding mode of PGJ2 to NF-B was unraveled by GOLD docking calculation. Subsequently, substitutions were made to PGJ2 to optimize its association with NF-B. Care was taken not to strongly increase the reactivity of the new compounds, and to keep the overall shape, size and hydrophilicity of the lead compound, which should render them a similar bioavailability. Molecular mechanics calculations were performed to decide on the suitability of the substitutions, and to evaluate the energies of association with NF-B. Density functional theory calculations were performed also to study the overall reactivity of the substituted drugs towards NF-B. Important general conclusions were obtained, concerning the improvement of these natural inhibitors; namely, a set of rational methodologies were deduced to improve the association between the PGJ2 derivatives and NF-B, and their efficiency demonstrated by generating a set of substituted complexes, some of them with a very much increased affinity for NF-B, opening new doors to enlarge the therapeutic capabilities of this class of drugs. 相似文献
967.
968.
969.
970.
We apply the master equation and non-linear Fokker-Planck techniques to a model with autocatalysis and (Michaelis-Menten, Langmuir-Hinshelwood) saturation law and the minimal set of reactive steps for a well posed problem is given. 相似文献