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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
This paper presents data relating to the performance of sprinklers and detectors in real office fire situations. For sprinklers, these data are additional to that associated with the standardized testing used to determine the design delivery density and pressure requirements for various occupancy situations, and provide a useful insight into the effect of sprinklers on developing fires with various office situations. The data given in this paper include the times for activation of various types of sprinkler heads (normal and fast response), the efficacy of the systems as far as extinguishment is concerned, estimates of the maximum size of the fires prior to commencement of extinguishment and associated air temperatures at various locations within the office enclosures. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
992.
M. L. Malinkovich 《Glass and Ceramics》2008,65(3-4):136-138
The capabilities of x-ray spectral instruments for fast analysis of raw materials and glass and ceramics were demonstrated. The range of the content of determinable elements in a sample ranges from 1 ppm to 100%. The measurement time is 10–15 sec. 相似文献
993.
The saturation capacity of n-alkanes in CHA, AFX and ERI zeolites, that consist of cages separated by windows, decreases with increasing carbon number. The major aim of the present communication is to demonstrate the possibility of separating n-alkane mixtures relying on differences in saturation capacities. To investigate this possibility, Configurational-Bias Monte Carlo simulations for adsorption of C3–nC6, nC4–nC6, and nC5–nC6 mixtures in CHA, AFX and ERI were carried out for equimolar bulk fluid phase. These mixture simulations show that for operation at fluid phase fugacities below about 1 MPa, the adsorbed phase in equilibrium with the bulk vapor phase is predominantly the alkane with the longer chain length, i.e. nC6. However, for operation at pressures in excess of 1 MPa, the adsorbed phase in equilibrium with the bulk liquid phase is richer in the component with the smaller chain length. In some cases, the nC6 is practically excluded from the zeolite. 相似文献
994.
K. O. Boltar I. D. Burlakov A. M. Filachev E. A. Klimanov V. P. Ponomarenko V. N. Solyakov V. I. Stafeev 《Optical Memory & Neural Networks》2007,16(4):234-247
The recent researches and technological developments of middle and long wavelength infrared HgCdTe photovoltaic detectors
are presented. Structure, topology, design and performance of HgCdTe photodiodes, silicon readout electronics, Focal Plane
Arrays both staring and time delay and integration types, thermal imagers are discussed. Negative differential conductance,
bistability and high frequency oscillations under background infrared radiation in HgCdTe photodiodes are reported. 相似文献
995.
996.
E. P. Velikhov N. N. Ponomarev-Stepnoi V. G. Volkov G. G. Gorodetskii Yu. A. Zverkov O. P. Ivanov S. M. Koltyshev V. D. Muzrukova S. G. Semenov V. E. Stepanov A. V. Chesnokov A. D. Shisha 《Atomic Energy》2007,102(5):375-381
This article is devoted to work done in 2002–2006 as part of the unified project Reabilitatsiya to rehabilitate radiation
hazardous objects and sections of the radioactively contaminated territory of the Russian Science Center Kurchatov Institute.
The main objects of the rehabilitation work were old storage sites built for radioactive wastes on the territory of the Institute
when military and civilian nuclear technologies were under development. The structural features of the storage sites, including
the volumes and characteristics of the wastes stored, are presented. The salient aspects of the disposal sites, taken into
account during the rehabilitation work, are discussed. The organization of the rehabilitation operations and the sequence
in which they are performed, the special features of the technical design solutions used, the technological methods, and ways
for conducting the work are described.
__________
Translated from Atomnaya énergiya, Vol. 102, No. 5, pp. 300–306, May, 2007. 相似文献
997.
Bestehen ausreichende Anhaltspunkte für die Hochwassergef?hrdung, ist die Gemeinde verpflichtet, sich durch Nachforschungen
Gewissheit über das Vorliegen oder Nichtvorliegen eines Hochwasserabflussgebietes gem § 38 Abs 3 WRG zu verschaffen. Liegt
ein solches vor, hat sie gem § 12 Abs 1 Z 2 krnt GplG dieses im Fl?chenwidmungsplan ersichtlich zu machen. Erteilt die Gemeinde
eine Baubewilligung ohne diese von der Erteilung einer wasserrechtlichen Bewilligung abh?ngig zu machen, haftet sie für die
Kosten der Bauführung, die bei gesetzes-konformer Vorgangsweise unterlassen worden w?re. 相似文献
998.
M. A. Gasanov 《Surface Engineering and Applied Electrochemistry》2007,43(5):398-402
We present the results of electric discharge treatment of zeolites for purifying the waste water from the manufacture of polymers. By application of the thermostimulated relaxation method, it has been revealed that in the zeolites, superficial and volumetric charges accumulate. It is shown that the electric discharge effects considerably enhance the efficiency of the adsorptive purification of waste water. 相似文献
999.
The optical properties of bismuth telluride crystals doped with donor-and acceptor-type impurities are studied. The fact that energy corresponding to the resonance frequency of plasma oscillations of free charge carriers (plasmons) approaches the band-gap energy is detected in the infrared spectral region, where the main elementary excitations in the electronic system of these materials are observed. The mentioned approach of energies varies the intensity of electron-plasmon interaction, which affects the recombination processes in the materials widely used for the fabrication of thermoelectric energy converters. 相似文献
1000.
Arash Sarhangi Fard Navid M. Famili Patrick D. Anderson 《Computers & Chemical Engineering》2008,32(7):1471-1481
The main objective of the present work is to modify the traditional mapping method for the simulation of distributive mixing of multiphase flows in geometries involving moving parts such as, internal mixers or twin-screw extruders without a limitation on their geometrical periodicity. The periodicity condition, limits the results of traditional mapping method to tracking mapping mesh between specific discrete time intervals or distances for that geometry is repeated, hence, result is only for fixed orientation of rotors. Imaginary domain method is introduced to track mapping mesh from one state to the next free of geometrical periodicity limitations. In this work the method is introduced and its applicability and accuracy is discussed in details. A two-dimensional (2D) simulation of mixing of two Newtonian fluids with different viscosities in an intermeshing internal mixer is used as a test case study. In this example the key issues of ability to predict mixing state in details for all orientations of rotors is presented. To reduce diffusion errors of mapping method in the boundaries of the rotors, mapping mesh refinement technique that relies upon one single reference mesh is also presented. 相似文献