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91.
In this paper, KdV-Burgers equation can be regarded as the normal equation of atmospheric turbulence in the stable boundary layer. On the basis of the travelling wave analytic solution of KdV-Burgers equation, the turbulent spectrum is obtained. We observe that the behavior of the spectra is consistent with actual turbulent spectra of stable atmospheric boundary layer.  相似文献   
92.
The level scheme of78Kr has been studied with the techniques of γ ray spectroscopy: decay spectra of78Rb produced by the reactions64Zn(16O,pn) and65Cu(16O,3n) have been measured; in-beam γγ coincidences have been taken during the irradiation of64Zn with16O ions; and an angular distribution measurement of γ rays from the reaction64Ni(16O, 2n)78Kr has been performed. Fifteen excited states in78Kr have been observed and spins have been proposed for most of these levels. A78Rb decay with a half-life of 17.5 ± 2 min has been found in addition to the previously known 6.0 ±0.2 min decay.  相似文献   
93.
TheÃ(020)κ3Π–X3Σ(000) andÃ3Πi(001)–X3Σ(000) bands of the CCO radical have been investigated by laser spectroscopy with two types of tunable laser system. An analysis was made simultaneously for both the bands to establish line assignments and determine molecular constants for both theÃ(020) andÃ(001) states. A coupling constant between these two states was also determined by assuming the interaction to be of Fermi type.  相似文献   
94.
A high-performance liquid chromatographic method was developed to determine arachidonic 5-lipoxygenase products in calcium ionophore-stimulated neutrophils. This procedure allows the simultaneous measurement of leukotriene B4 (LTB4) and its omega-oxidation products without using a gradient elution system. 20-Carboxy-LTB4, 20-hydroxy-LTB4, 6-trans-LTB4, 12-epi-6-trans-LTB4, LTB4 and 5s,12s-dihydroxyeicosatetraenoic acid can be separated and quantitated by reversed-phase chromatography using isocratic elution. The generation and degradation of 5-lipoxygenase products by human neutrophils following stimulation with calcium ionophore have been examined by this method.  相似文献   
95.
96.
A method is given for the analysis of long-chain branching in polymers by using combined GPC and intrinsic viscosity measurements. A computer program was written to evaluate branching indices by a tabular, iterative method. The method was applied to the evaluation of long-chain branching in low-density polyethylene.  相似文献   
97.
A new on-line isotope separator was constructed and used successfully for the study on short-lived isotopes at the Bevalac at Lawrence Berkeley Laboratory. The isotopes were produced through projectile fragmentation processes of high energy heavy-ion reactions. Various isotopes were rigidity-separated by use of a beam line and, finally, the desired single isotope was range analyzed to stop in a catcher. A large number of β-emitting21F nuclei were successfully collected and the nuclear lifetime was determined by detecting β-rays.  相似文献   
98.
Double-tethered polymers are a kind of linear polymer with a peculiar topological constraint; that is, both of its end-points are attached to a plane which the polymer segments cannot penetrate. The effects of the constraint on the polymer's configurational and entropic properties were investigated by means of a three-dimensional lattice simulation that combined a previously proposed idea with a very efficient chain generation algorithm. In particular, the value of a topology-dependent critical exponent was estimated for the double-tethered configurations. This data is the first report on isolated and double-tethered chains. Also, two optional types of tethered-polymer were investigated as asymptotes of the double- and single-tethered configurations.  相似文献   
99.
Abstract

The 2-(phenylcarbamoyl)ethyl group bonded to the cobalt atom in cobaloxime complexes was isomerized on exposure to visible light in the solid-state. The three complexes with different amines as axial base ligands were prepared and their crystal structures were determined by X-ray analysis. The reaction rates in the solid-state were mainly affected by the hydrogen bonds of the reactive group with the neighboring molecules and the occupation of crystal solvent molecules around the reactive group.  相似文献   
100.
Probe electrospray ionization (PESI) uses a sharp solid needle as electrospray emitter. This method was found to be applicable to the analysis of real‐world samples with high concentrations of salts and detergents without sample pretreatment. Since PESI is only applicable to wet samples but not to dry samples, sheath‐flow PESI (SF‐PESI) has been developed. The metal needle was inserted into the fine plastic capillary with a protrusion of 0.1–0.2 mm from the capillary terminus. The solvent was supplied continuously through the capillary. At the lowest position of the probe, solvent flowing out from the capillary makes the sample wet and extracts the analytes from the surface. The extracted analytes were electrosprayed at the highest position of the needle. SF‐PESI was successfully applied to samples such as narcotics, tablets, bill, fruits, potatoes, etc. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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