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981.
Common pharmaceutical excipients and compounds were dried either by a simple convection method or by a combined convection and microwave method in a static bed or by a combined microwave and vacuum method in a mixed bed. A simple placebo granulation was dried by an exclusive vacuum method and by a combined microwave and vacuum method in a mixed bed. The results were compared. 相似文献
982.
G Franzosi E Battistel I Gagliardi W Van der Goes 《Canadian Metallurgical Quarterly》1995,43(3):508-513
A screening of microorganisms producing glutaryl-7ADCA acylase, an enzyme able to hydrolyse glutaric acid selectively from glutaryl-3-deacetoxy-7-aminocephalosporanic acid (glutaryl-7ADCA), has been carried out in soil samples. Five microorganisms expressing acylase activity were isolated and classified as Bacillus cereus, Achromobacter xylosooxidans, Bacillus sp., Pseudomonas sp. and Pseudomonas paucimobilis. The screening was carried out by preparing enrichment cultures containing glutaryl-7-ADCA or cephalosporin C as the selective carbon source. Four model compounds (adipoyl-, glutamyl- and glutaryl-p-nitroanilide and glutarylcoumarin), mimicking the glutaryl-7ADCA beta-lactam moiety, were synthesized as substrates suitable for the rapid screening of the microorganisms (2500) isolated from the enrichment cultures. A total of 300 strains were active on the model substrates and only 5 displayed acylase activity on glutaryl-7ADCA. The fermentation parameters, such as pH and inducer concentration, for the optimal acylase expression and acylase specificity towards the model substrates were different for each strain. 相似文献
983.
The advantages and disadvantages of using a high-pressure pneumatic pump at porcelain and insulator works are discussed. The testing results of a prototype pump are described. 相似文献
984.
For pt.1 see ibid., p.53-69 (2002). The authors discuss several important special cases of the problem solved in Part I. These are: disturbance attenuation and passivation, the full information case, the filtering problem, and the case that the to-be-controlled plant is given in input-state-output representation. An interesting aspect is the notion of full information, which we define in terms of the observability of the to-be-controlled variables from the control variables. When the system is given in state space form, we obtain conditions for the existence of a controller that renders a system dissipative in terms of two coupled algebraic Riccati inequalities. The controller turns out to be a feedback system with a transfer function that is proper, but, in general, not strictly proper. Another issue that we study in this paper is feedback implementability. We find conditions under which, in the context of synthesis of dissipative systems, a controlled behavior can implemented by a feedback controller 相似文献
985.
Methods are proposed for obtaining the elastic and absorbed components of deformation and mechanical work expended in the region of a nondestructive mechanical effect from the stress-strain diagrams or by calculated prediction. The closeness of the values of the absorbed and correspondingly the elastic components obtained with the measured or predicted stress-strain diagram totally confirm the satisfactory reliability of modeling the physicomechanical properties of a fibre in the form of an integral equation in which the nonlinear-hereditary kernel analytically reflects the activating character of the mechanical effect combined with the concept of the deformation-time analogy in normalized form [5]. 相似文献
986.
V. M. Piksaikin L. E. Kazakov G. G. Korolev S. G. Isaev V. A. Roshchenko M. Z. Tarasko 《Atomic Energy》2002,92(2):147-155
The relative yield of delayed neutrons and the half-life of their precursor nuclei in fissioning of 233U, 235U, and 239Pu by epithermal neutrons are measured on a setup which is based on a KG-2.5 electrostatic accelerator. The experimental samples are irradiated in a polyethylene cube, one face of which is irradiated by a neutron beam consisting of T(p, n)3He neutrons. A procedure is developed for averaging the group parameters of delayed neutrons from different series of measurements, taking account of their correlation. A comparative analysis of the data of this work and in ENDF/BVI in terms of the average half-life of the precursor nuclei of the delayed neutrons and using the dependence of the reactivity on the asymptotic period of the reactor is performed.It is shown that the data of this work agree, to within the uncertainty limits, with the recommended experimental data and differ substantially from the ENDF/BVI data. 相似文献
987.
Dr. Jana Buchwalter Prof. Dr. Walter Brenner Dr. Rüdiger Zarnekow 《WIRTSCHAFTSINFORMATIK》2002,44(4):345-353
Many companies and purchasing departments only possess a limited knowledge about the modelling of inter-company business processes for electronic procurement. In the past the discussion about electronic procurement was mostly focused on technical aspects. This article introduces a reference process model for procurement auctions. The process model is made up of a basic process, which describes a minimal process for procurement auctions, and a number of process alternatives, which allow for the adoption of the basic process to changing parameters and individual company requirements. 相似文献
988.
L. T. Ashchepkov G. E. Kolpakova Yu. B. Stegostenko 《Automation and Remote Control》2002,63(5):693-701
Stabilization of the trajectories of a linear discrete system closed by dynamic feedback under interval uncertainty of the equations of motion and observation is studied. Sufficient conditions of stabilizability are formulated. Results of numerical experiments are given. 相似文献
989.
G.P. Berman G.D. DoolenG.V. López V.I. Tsifrinovich 《Computer Physics Communications》2002,146(3):324-330
We demonstrate a strategy for implementation a quantum full adder in a spin chain quantum computer. As an example, we simulate a quantum full adder in a chain containing 201 spins. Our simulations also demonstrate how one can minimize errors generated by non-resonant effects. 相似文献
990.
The conventional application of reduction factors to response spectrum analysis results is inappropriate for the abutment shear forces, which are based on elastic action. On the other hand, adopting the unreduced values from the elastic dynamic analysis does not achieve equilibrium among the abutment shear forces, deck inertia forces, and reduced pier forces. A simplified method is here proposed for the assessment of the shear on the abutments, documented by comparison with response spectrum and time history nonlinear analyses for several bridge configurations. For the analyzed configuration of the bridge with an internal movement joint, the response spectrum analysis underestimates the shear on the abutment for low values of the abutment flexibility and overestimates it when the stiffness of the abutments becomes higher than that of the piers. In all the case studies analyzed, the proposed method approximates the time history results better than the response spectrum. 相似文献