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981.
A. Da Settimo C. Primofiore G. Biagi V. Santerini 《Journal of heterocyclic chemistry》1976,13(1):97-100
Some derivatives of 11H-indolo[3,2-c] [1,8]naphthyridine, a new heterocyclic system, have been prepared using the Fischer indole synthesis on the appropriately phenylhydrazones. The preparation of some substituted 5,6-dihydro-11H-indolo[3,2-c][1,8]naphthyridines is also described. 相似文献
982.
L. D'Haenens C. C. Van De Sande M. Schelfaut M. Vandewalle 《Journal of mass spectrometry : JMS》1987,22(6):330-333
The chemical ionization (CI) mass spectra of the 2-tert-butyl-substituted 1,3-cyclopentane- and 1,3-cyclohexanediol diacetates and dimethyl ethers have been determined using isobutane and methane as reagent gases. From the differences in the spectra of these compounds, it clearly follows that steric and conformational effects are expresssed in the CI mass spectra. The relative impact of these effects, however, is strongly dependent on diol derivatization and 2-alkyl substitution. 相似文献
983.
C. Bagnasco P. Ciambelli S. Crescitelli G. Russo 《Reaction Kinetics and Catalysis Letters》1978,8(3):293-300
Cytalysts containing manganese, cobalt or nickel oxides supported on -alumina were physically characterized and tested for the oxidehydrogenation of ethylbenzene. The physical characterization shows surface spinel formation and/or metal oxide segregation for the systems cobalt-alumina and nickelalumina, but Mn2O3 segregation only for the manganese system. The catalytic activity data indicate a promoting effect of Mn2O3 and cobalt aluminate, while the presence of Co3O4 results in a lower activity.
, , -Al2O3, . / - , Mn2O3 . , Mn2O3 , Co3O4) .相似文献
984.
ENHANCED SUSCEPTIBILITY TO HPD-SENSITIZED PHOTOTOXICITY AND CORRELATED RESISTANCE TO TRYPSIN DETACHMENT IN SV-40 TRANSFORMED IMR-90 CELLS 总被引:1,自引:0,他引:1
Steven C. Denstman Larry E. Dillehay Jerry R. Williams 《Photochemistry and photobiology》1986,43(2):145-147
Abstract— The response of a normal human cell strain, IMR-90 and a line derived from it by SV40 transformation were compared after treatment in vitro with hematoporphyrin derivative (HPD) and red light. Transformed cells were inactivated at a significantly higher rate than normal cells when assayed by clonogenic survival. Co-treatment with HPD and light also induces cellular resistance to enzymatic cleavage by trypsin; transformed cells exhibit a greater resistance than the normal cells to detachment from the growing surface. These data indicate that transformed cells may possess intrinsic characteristics that render them more sensitive than normal cells to HPD-induced phototoxicity and that the plasma membrane may be the site of differential toxicity. 相似文献
985.
A limited-memory filter is described for analytical measurements which are affected by unpredictable changes. The filter is capable of reducing the effects of those changes. Applications in multicomponent determinations, control charts and spectra smoothing are discussed. For the last application, a less abrupt type of limited-memory filtering, called facing-memory filtering, is described. 相似文献
986.
A. Lukš J. Peřina V. Peřinová M. Bertolotti C. Sibilia 《Czechoslovak Journal of Physics》1984,34(8):855-861
Conclusions This discussion concerning the probability density confirms in a new way the results obtained in paper [1] in which a two-peak behaviour of the photocount distribution has been found. This general result depends on the particular nonlinear interaction scheme, and the bistable behaviour is caused by quantum fluctuations produced by the nonlinear interaction.As losses are not taken into account, other kinds of fluctuations that can modify the bistable behaviour are not accounted for in this paper. 相似文献
987.
The determination of fluoridation rate provides a relatively inexpensive time-average surveillance method for monitoring atmospheric fluorides in specific areas. The fluoride is collected by the reaction with calcium oxide coating on a filter paper strip during the exposure of the candle to ambient air. The collected fluorides are then extracted from the exposed filter paper into a buffer solution and subsequently determined by ion selective electrode. 相似文献
988.
The molecular structure of 1,2,4-triazole has been determined by gas phase electron diffraction. The intemuclear distances and bond angles were obtained by applying a least-squares analysis to the experimental intensity. The bond distances (rg) and bond angles were N1-N2 = 1.380 ± 0.010 Å, N2C3 = 1.329 ± 0.009 Å, C3-N4 = 1.348 ± 0.009 Å, N1-C5 = 1.377 ± 0.004 Å, N4C5 = 1.305 Å (calculated value). N-H = 0.990 Å, C-H = 1.054 Å, ∠N1N2C3 = 102.7± 0.5°, ∠N2C3N4 = 113.8 ± 1.3°, ∠N2N1C5 = 108.9 ± 0.8°, ∠H1N1N2 = 110.9°, ∠H2C3N4 = 119.2°, ∠H3C5N1 = 131.0°, ∠C3N4C5 = 105.7° (calculated value) and ∠N4C5N1 = 108.7° (calculated value). 相似文献
989.
The comparatively non Cu-complexing surfactant, gelatin, has been substituted on the HMDE for natural organic material during DPASV assay of estuarine waters. It is shown that the effects of adsorption of natural organic material on the electroreduction and electrooxidation of Cu are diverse and act in part through the complexing properties of the organic material. 相似文献
990.
D. C. Dejongh R. Y. Van Fossen Laurence R. Dusold M. P. Cava 《Journal of mass spectrometry : JMS》1970,3(1):31-43
The mass spectra of eleven diazoketones have been obtained. High resolution mass measurements of selected ions have shown initial loss of nitrogen followed by loss of carbon monoxide. In many of the spectra, flat-topped metastables were observed. 相似文献