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961.
962.
We show that the coefficients of Ramanujan's mock theta functionf(q) are the first non-trivial coefficients of a canonical sequenceof modular forms. This fact follows from a duality which equatescoefficients of the holomorphic projections of certain weight1/2 Maass forms with coefficients of certain weight 3/2 modularforms. This work depends on the theory of Poincaré series,and a modification of an argument of Goldfeld and Sarnak onKloosterman–Selberg zeta functions.  相似文献   
963.
This report describes the development of novel wired chip devices for mu-HPLC analyses. The monolithic capillary column to be wired was prepared using a tri-functional epoxy monomer, tris(2,3-epoxypropyl)isocyanurate with a diamine, 4-[(4-aminocyclohexyl)methyl]cyclohexylamine. The prepared column was evaluated by SEM observation of the sectional structure of column and micro-HPLC. In addition, the reproducibility in the preparation of long capillary columns having nearly 1 m length was extensively examined for applications of novel wired chip devices. The authors demonstrated that the monolithic structure of the prepared long capillary could be finely controlled under the strictly maintained operational conditions and thus the relative standard deviation (RSD) of the column properties such as the number of theoretical plates, retention factor, and permeability could be well controlled to become less than 10%. Furthermore, the wired chip device column showed that its high performance was kept even after chip preparation.  相似文献   
964.
965.
Studies on the mode of action of two boroncontaining anti-neoplastic agents, ethylamine-carboxyborane and triphenylphosphine-carboxyborane, are reported. The major site of inhibition was in the pyrimidine de nove synthetic pathway at orotidine monophosphate decarboxylase activity. Additional sites which may facilitate the inhibition of cell growth were IMP dehydrogenase, thymidine kinase, TMP kinase and TDP kinase, m-RNA, r-RNA and t-RNA polymerase activities as well as topoisomerase II activity. The reduction in enzyme activities led to sufficient reduction of d(NTP) levels to suppress DNA synthesis and cell growth. DNA strand scission was evident in the presence of drug. Multiple modes of action are common with amine-carboxyboranes. Acute toxicity studies in mice showed that both agents were safe in their therapeutic range based on organ weights, histological tissue sections, clinical chemistry values and hematopoietic parameters.  相似文献   
966.
The electronic states of Cd-chalcogenide microcrystals embedded in GeO2 glasses are discussed through the photo-luminescence spectra obtained by steady-state and dynamical spectroscopies. The photoacoustic absorption spectra as well as the steady-state and transient absorption spectra are also presented briefly in order to bring about a better understanding of their electronic states.  相似文献   
967.
Treatment of cyclic or acyclic -haloenones with various carbon nucleophiles involving active methylene functions afforded the corresponding dihydrofurans in a stereoselective manner with good to high yields. This reaction system can provide a general and practical methodology for the construction of dihydrofuran rings.  相似文献   
968.
High-resolution 13C spectra of solid polymers are often acquired with cross polarization with magic angle spinning (CP/MAS) to take advantage of the abunda ntly available protons in the polymer chains. The sequence for transferring mag netization from 1H to13C using Hartmann-Hahn spin locking in the rotating frame is now a standard in commercial solidstate NMR spectrometers.  相似文献   
969.
To investigate the characteristics of N2O concentration, we applied several types of time series analyses such as fast Fourier transform (FFT), auto-correlation, and cross-correlation, to 2.5-year time series data of trace N2O concentration continuously monitored by gas chromatography and meteorological data, measured in an urban area of Nagoya. It was found that there is a positive correlation between atmospheric N2O concentration (ppbv) and, both steam pressure (hPa) and temperature (°C). In addition, negative and positive correlations in atmospheric pressure and in solar flux were also found, respectively. These findings suggest an enrichment of N2O through environmental steam during the summer season, particularly in urban areas. On the other hand, the correlation to wind direction shows a variation with amplitude of 7 ppbv, from the north-west to the south-east, and a seasonal variation up to 12 ppbv, from winter to summer. These results support the hypothesis that atmospheric steam controls the N2O concentration in urban areas. In addition, the correlation with wind direction suggests the existence of an emission source in the direction of seaside areas.  相似文献   
970.
Ken Sekimoto 《Physica A》1984,125(1):261-269
We construct the evolution equation of the size distribution function of the unswitched domains of a model of a 1-D system in a switching field, and solve it as an initial value problem. As the time goes on, the distribution approaches to the “fixed point”, which is the exponential distribution. This feature is unaffected by the finiteness of the critical radius of nucleation.  相似文献   
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