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71.
赵惠琴 《有色冶金设计与研究》2004,25(4):4-8
根据所使用的低水泥浇注料的性能,对中铝山西分公司检修厂4号焙烧炉制定了合理的烘烤曲线,提高了耐火内衬的质量,延长了内衬的使用寿命。 相似文献
72.
Burns G. Leonard; Gomez Rapson; Walsh James A.; de Moura Marcela Alves 《Canadian Metallurgical Quarterly》2003,15(1):118
G. J. DuPaul (see record 2003-02033-012) offered two suggestions for additional research to understand the strong source effects reported by R. Gomez, G. L Burns, J. A. Walsh, and M. A. de Moura (see record 2003-02033-001) in attention-deficit/ hyperactivity disorder (ADHD) rating scales. The first suggestion was to determine whether the source effects represent mostly bias or accuracy. The second suggestion was to minimize source effects through the development of better ADHD rating scales. Because source effects can represent bias or accuracy, it is important to minimize the bias aspect through content validation procedures prior to attempts to determine whether source effects better reflect bias or accuracy. This comment offers various suggestions to reduce the bias in ADHD rating scales. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
无键联接传动的特点及锥面弹性衬套设计和应用 总被引:5,自引:0,他引:5
无键联接在特殊行业和工况中是键联接传递动力和运动的有力补充,介绍了工程上应用的圆弧三边形型面联接、弹性环无键联接、圆柱面过盈联接等几种无键联接传动方式及其工作原理,并分析了各自的性能特点和应用情况。针对无键联接传动的特点、特殊行业和工况的应用实际,设计了锥面弹性衬套无键联接传动结构并介绍了其在工程中的实际应用。 相似文献
74.
Murat K. Aktas 《International Journal of Heat and Mass Transfer》2003,46(12):2253-2261
Effects of thermoacoustic wave motion on the developing natural convection process in a compressible gas-filled square enclosure were investigated numerically. In the cases considered, the left wall temperature is raised rapidly (impulsively or gradually) while the right wall is held at a specified temperature. The top and the bottom walls of the enclosure considered are thermally insulated. The numerical solutions of the full Navier-Stokes equations were obtained by employing a highly accurate flux-corrected transport algorithm for the convection terms and by a central differencing scheme for the viscous and diffusive terms. The strength of the pressure waves associated with the thermoacoustic effect and resulting flow patterns are found to be strongly correlated to the rapidity of the wall heating process. Fluid thermal diffusivity was found to affect the strength of the thermoacoustic waves and the resulting interaction with the buoyancy-induced flow. 相似文献
76.
本文使用吹扫捕集法来前处理水样,用带有电子捕获检测(ECD)的气相色谱仪来测定水中三卤甲烷(THM)_s。水样加标回收率在85%~115%之间,相对标准偏差在5%左右。实验结果表明,该法具有简单、快速、灵敏的特点。 相似文献
77.
M. Hädrich N. Lorenz H. Metzner U. Reislöhner S. Mack M. Gossla W. Witthuhn 《Thin solid films》2007,515(15):5804-5807
In this paper, we describe our new baseline for CSS-CdTe-CdS solar cells on 10 × 10 cm2 substrates. The deposition of the p-n junction and all the following steps were performed at the Institut für Festkörperphysik (IFK) in Jena. Using the new baseline, we are already able to produce solar cells with similar properties as commercial ones. In the batch type process, all manufacturing steps can be investigated separately. We employ Rutherford backscattering spectrometry (RBS), X-ray diffraction (XRD) and external quantum efficiency (EQE) measurements to characterise the structure of the bulk materials and interfaces. It is demonstrated that by RBS the front contact becomes accessible for thinned CdTe films. At the back contact, RBS spectra show a tellurium accumulation which is due to etching. This tellurium rich layer is confirmed by XRD with Rietveld refinement. The intermixing at the CdS-CdTe interface caused by the activation step is quantified by a bandgap determination based on EQE measurements. From the bandgap energy of the CdTe1 − xSx compound, we calculated the sulphur fraction x at the interface. XRD measurements imply that the activation step induces a (111) texture in CdTe. With regard to an improved manufacturing process, our cells are compared to industrial cells produced by Antec Solar Energy. 相似文献
78.
Franz Schauer 《Solar Energy Materials & Solar Cells》2005,87(1-4):235
Basic suppositions and microphysical origin of the occurrence of the space-charge-limited currents (SCLC) are presented in general and for the temperature-modulated space-charge-limited currents (TM-SCLC) in particular. The criteria are given for the spectroscopical method TM-SCLC to be used for localized electron states elucidation in organic semiconducting materials for organic solar cells optimization and modelling. The “visibility “of the localized states by SCLC method, i.e. the power of the SCLC method to distinguish the localized states, is tested by the modelling, varying the temperature, energy position of localized states and their concentration. Generally, it was determined that the SCLC measurements results are more reliable with the increased energy of the states, with their increased concentration and with decreased temperature. The correlation (or its absence) between the measured current and activation energy on applied voltage, expressed by the dependence of preexponential factor of conductivity on activation energy (Meyer–Neldel rule), gives the possibility to determine the energy range where the reconstruction of density of localized states function is reliable. 相似文献
79.
文章较系统地论述了车铣复合机床设计方案的形成过程,同时分析了该设计方案的持点,并简要介绍了该产品的主要技术参数和用途,简评了该产品的技术水平。 相似文献
80.
ROI-based Watermarking Scheme for JPEG 2000 总被引:1,自引:0,他引:1
Yu-Cheng Fan Arvin Chiang Jan-Hung Shen 《Circuits, Systems, and Signal Processing》2008,27(5):763-774
A new region of interest (ROI)-based watermarking method for JPEG 2000 is presented. The watermark is embedded into the host
image based on the characteristics of the ROI to protect rights to the images. This scheme integrates the watermarking process
with JPEG 2000 compression procedures. Experimental results have demonstrated that the proposed watermark technique successfully
survives JPEG 2000 compression, progressive transmission, and principal attacks. 相似文献