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111.
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113.
Éhen Zs. Novák Cs. Sztatisz J. Bene O. 《Journal of Thermal Analysis and Calorimetry》2004,78(2):427-440
Four amino acids and four different hair samples were studied in order to get information about the decomposition of human
hair, using combined (TG-MS) and DSC techniques. The thermal stability of the investigated amino acid samples was different.
Since they contain identical functional groups (-NH2, -COOH) some common mass/charge units were identified. However, due to their different chemical composition remarkable differences
have also been obtained. The results of the investigation of the amino acids were helpful to study the thermal fragmentation
of the hair samples. In our experiments, the effect of the heating rates was also studied.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
114.
115.
M. E. Élyashberg Yu. Z. Karasev É. R. Martirosyan 《Journal of Structural Chemistry》1995,36(3):502-509
Major axioms underlying structure elucidation of molecules by their characteristic spectral data are considered. The amount
of information obtained by solving the problem on structure elucidation of molecules serves as a basis to evaluate the quality
of solution. Conditions for computer-aided solution of problems using expert systems (ES) are analyzed. Reasons for incorrect
or zero solutions and for inconsistencies leading to negative results are examined. The role of additional information as
a necessary condition for correct solution is discussed. On the basis of this analysis, a general strategy for structure elucidation
of molecules by their spectra using ES is suggested. The principal idea is to use the iteration method, gradually increasing
the rigidity of constraints. Strategies named ARCHEOLOGIST and SCULPTOR are discussed. Examples are given.
Russian Scientific Research Institute of Organic Synthesis. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 3, pp. 548–558, May–June, 1995.
Translated by L. Smolina 相似文献
116.
An analysis is made of the possibility of focusing 10–30 keV charge-compensated proton beams with a current of 1 kA and an
area compression coefficient >1.5×103. To obtain a high degree of compression a combination of ballistic focusing and magnetic compression is used. The parameters
of the focusing channel are determined and an estimate is made of the possible effect of the compensating electron background
on the effectiveness of focusing of the proton beam.
Zh. Tekh. Fiz. 67, 73–80 (May 1997) 相似文献
117.
Thekth-order asymptotic solution of a standard system with lag is constructed along trajectories calculated according to the averaging scheme of A. N. Filatov. If the perturbation parameter 1, then the use of the step method for finding the solution is connected with cumbersome calculations because the number of required steps is inversely proportional to . We suggest another approach in which the step method is used onlyk times fort [0,k] and justify the asymptotic method.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 46, No. 10 pp. 1362–1368, October, 1994. 相似文献
118.
Summary We studied the dehydrogenation of 1-methylcyclopentene in the presence of an alumina-molybdenum catalyst at 600°, a flow rate of 1.0 h–1 and residual pressures of 20 and 100 mm of Hg. In both cases the yield of methylcyclopentadiene amounted to 30% based on the starting hydrocarbon.We express our deep appreciation to É. G. Ostapenko and E. D. Tulupova for assistance in performing the Chromatographic analyses.Translated from Izvestiya Akademii Nauk SSR, Seriya Khimicheskaya, No. 5, pp. 912–914, May, 1964 相似文献
119.
ADOLFO V. T. CARTAXO JOÃO L. REBOLA NATAŠA B. PAVLOVIĆ PEDRO M. A. CHARRUA DANIEL D. T. FONSECA JOSÉ A. P. MORGADO 《Fiber and Integrated Optics》2013,32(3-4):331-352
Abstract This article introduces the main achievements resulting from the DWDM/ODC project. The five areas of research activity within the DWDM/ODC project cover some of the main issues of design and development of dense wavelength division multiplexing systems for transparent optical networks. These issues are: performance assessment with arbitrary optical filtering; performance of signaling formats; dispersion compensation strategies for directly and externally modulated systems in presence of nonlinear transmission-induced degradation; and the impact of noise and crosstalk in the extent of transparent optical networks. All five areas of research activity have contributed significantly to a better understanding of the limitations present in dense wavelength division multiplexing systems. 相似文献
120.
Effects of Ultraviolet Radiation (UVA+UVB) and Copper on the Morphology,Ultrastructural Organization and Physiological Responses of the Red Alga Pterocladiella capillacea 下载免费PDF全文
Éder C. Schmidt Marianne Kreusch Marthiellen R. de L. Felix Debora T. Pereira Giulia B. Costa Carmen Simioni Luciane C. Ouriques Francine L. Farias‐Soares Neusa Steiner Fungyi Chow Fernanda Ramlov Marcelo Maraschin Zenilda L. Bouzon 《Photochemistry and photobiology》2015,91(2):359-370
The effect of ultraviolet (UV) radiation and copper (Cu) on apical segments of Pterocladiella capillacea was examined under two different conditions of radiation, PAR (control) and PAR+UVA+UVB (PAR+UVAB), and three copper concentrations, ranging from 0 (control) to 0.62, 1.25 and 2.50 μm . Algae were exposed in vitro to photosynthetically active radiation (PAR) at 70 μmol photons m?2 s?1, PAR + UVB at 0.35 W m?2 and PAR +UVA at 0.70 W m?2 during a 12‐h photocycle for 3 h each day for 7 days. The effects of radiation and copper on growth rates, content of photosynthetic pigments and photosynthetic performance were analyzed. In addition, samples were processed for light and transmission electron microscopy. The content of photosynthetic pigments decreased after exposure to radiation and Cu. Compared with PAR radiation and copper treatments modified the kinetics patterns of the photosynthesis/irradiance curve. The treatments also caused changes in the ultrastructure of cortical and subcortical cells, including increased cell wall thickness and accumulation of plastoglobuli, as well as changes in the organization of chloroplasts. The results indicate that the synergistic interaction between UV radiation and Cu in P. capillacea, led to the failure of protective mechanisms and causing more drastic changes and cellular imbalances. 相似文献