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101.
K. A. Soubbotin V. A. Smirnov S. V. Kovaliov H. J. Scheel E. V. Zharikov 《Optical Materials》2000,13(4):405-410
Single crystals of germanoeucryptite doped by chromium (IV) have been grown for the first time. Spectroscopic properties of grown crystals have been investigated. The intensive broadband fluorescence of Cr4+-ions in the range between 1070 and 1600 nm was observed with lifetime 10 μs. Preliminary investigations show that this material is promising for use as an active medium for new tunable solid-state laser of near IR-region. 相似文献
102.
T. Hahn 《Computer Physics Communications》2008,178(3):217-221
This note describes a Mathematica interface for Fortran code generated by FormCalc. The interfacing code is set up automatically so that only minuscule changes in the driver files are required. The interface makes a function to compute the cross-section or decay rate available in Mathematica. This function depends on the model parameters chosen for interfacing in the Fortran code. 相似文献
103.
104.
田利伟 《建筑热能通风空调》2011,30(2):28-32
通过大型环境风洞试验的方法,研究了绿化隔离带以及中隔墙对城市交通隧道洞口污染的扩散进行了研究.对于设置绿化隔离带工况,研究了不同风速大小/风向下绿化隔离带对废气的洞口直接排放中污染物扩散影响,获得了洞口排放污染物在不同来流风速/风向条件下的浓度衰减规律及其影响范围;对于设置中隔墙工况,试验涉及了三种不同中隔墙长度(隧道... 相似文献
105.
An investigation of the effects of humidity and salt crystallisation on medieval masonry has been undertaken at the parish church of Walpole St Andrew, Norfolk, with the intention of establishing a relationship between changes in environmental conditions and levels of stone decay. Masonry within the church has been contaminated with sodium chloride salts, which are undergoing cycles of crystallisation/dissolution in response to fluctuations in relative humidity corresponding to the equilibrium relative humidity of the salt. The effects of these cycles have been determined by a combination of gravimetric analysis, ion chromatography, and qualitative assessment of deposited material. Appropriate remedial action, based on a combination of desalination techniques and environmental control, is put forward for discussion. 相似文献
106.
张泰 《青岛理工大学学报》1997,(1)
论述了集装箱起重机减摇系统的工作原理,对减摇装置的摆幅、摆动周期和衰减时间进行了计算,并建立了减摇系统的摆动方程 相似文献
107.
An empirical approach has been developed to predict the total entrainment flux at different levels of freeboard height. The approach is based on the results of experimental investigations carried out in a 152 mm diameter column, with FCC as the feed powder. The powder was fluidized at superficial gas velocities of 0.2 m/s and 0.7 m/s. 相似文献
108.
L. Young 《Electrochimica acta》2008,53(22):6542-6544
The decrease with time in the capacitance of anodic oxide films on tantalum after ceasing film growth by reducing the field in the oxide was investigated. No dependence was observed of the amount and rate of change in relative dielectric permittivity on the initial current density. The kinetics of this effect are therefore different from those for the decay of the latent ionic conductivity. 相似文献
109.
T. Soldner L. Beck K. Schreckenbach A. Bussire R. Kossakowski P. Liaud O. Zimmer 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2000,440(3):643-647
The new detector TRINE (time reversal invariance neutron experiment) was developed to test the time reversal invariance in the neutron decay. The precision of former experiments can be improved by one order of magnitude with an improved proton detection, a better background suppression and an angular resolving measurement using multiwire proportional chambers in coincidence with plastic scintillators, and the higher neutron flux and polarization available today. The concept of the detector and the status of the project is discussed. 相似文献
110.
D. Scaglione S. Caffaz E. Bettazzi C. Lubello 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(8):1250-1254
This paper describes an experimental method used to evaluate the anaerobic ammonium oxidation (Anammox) decay coefficient by means of a batch test. The test was carried out using an experimental procedure based on manometric measurements of the dinitrogen gas that is produced by the Anammox process. The accuracy of the procedure had previously been assessed, and the method was used to determine the specific Anammox activity (SAA mg N2‐N g VSS?1 d?1,) and the maximum nitrogen production rate (MNPR, NmL N2 L?1 d?1) under several different conditions. A specific batch test, which lasted for 148 days, was performed to assess the decay coefficient. The activity decrease was monitored and the estimated value of the decay coefficient was found to be 0.0048 d?1 at 35 °C, for which the corresponding half‐life time of the Anammox biomass was 145 days. This value is higher than other values reported in the literature, but in accordance with the slow growth rate of the Anammox bacteria. Copyright © 2009 Society of Chemical Industry 相似文献