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11.
在未来勘探开发中研发的推动作用   总被引:2,自引:1,他引:1  
在过去的20年里,尽管油价和经营环境不断发生着变化,但勘探开发的产量和经济效益持续增长着,科学研究和先进技术起了关键作用。未来的勘探开发将更加依赖于先进的技术和科学的研究开发。 随着变化的经营环境和关键的先进科学技术强有力的结合,出现了新的研发模式和发展趋势。在这里我们  相似文献   
12.
Several N-(phosphonomethyl) amides have previously been reported to act as particularly effective flame retardants for cellulose. It has also been demonstrated previously that the efficiency of a flame retardant on cellulose frequently parallels its ability to phosphorylate cellulosic hydroxyls at elevated temperatures. This study of the hydrolysis and alcoholysis reactions of N-(phosphonomethyl) amides establishes their unique reactivity. An explanation for this high reactivity is proposed on the basis of intramolecular assistance of the attack of water or alcohols at phosphorus by the carbonyl oxygen of the amide moiety.  相似文献   
13.
The present study explores the relation among 4 personality traits associated with impulsive behavior and alcohol abuse. Personality traits were measured using the 4 subscales of the UPPS Impulsive Behavior Scale (UPPS: S. P. Whiteside & D. R. Lynam. 2001). The UPPS and measures of psychopathology were administered to clinical samples of alcohol abusers high in antisocial personality traits (AAPD), alcohol abusers low in antisocial personality traits (AA), and a control group (total N = 60). Separate analyses of variance indicated that AAPDs had significant elevations on all 4 UPPS scales, whereas the AAs and controls differed only on the Urgency subscale. However, when controlling for psychopathology, group differences on the UPPS scales disappeared. The results suggest that personality traits related to impulsive behavior are not directly related to alcohol abuse but rather are associated with the elevated levels of psychopathology found in a subtype of alcohol abusers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In this paper results on surface photovoltage (SPV) and electron beam induced conductivity (EBIC) studies of edge-defined film-fed growth (EFG) and floating zone (FZ) silicon solar cell materials (both p-type) are presented. A systematic comparison based on minority carrier diffusion length and carrier recombination is made between: (i) samples contaminated with Ti and/or Fe, (ii) samples gettered by phosphorous diffusion, and (iii) as-received samples. Deep level transient spectroscopy (DLTS) measurements, together with the iron-boron (FeB) pairing kinetics [1] have successfully been used to detect the presence of Fe in the samples. Even though this process is effective in revealing Fe impurities in p-type FZ silicon it is evidently not suitable for Fe identification in p-type EFG silicon. Ti, like Fe, is found to be a prominent lifetime-limiting metallic impurity in both EFG and FZ silicon. Phosphorous diffusion is proven to be an effective external gettering technique for fast-diffusing impurities such as Fe, but not for Ti.  相似文献   
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Describes methods and techniques of play therapy for use with multicultural and diverse populations. Barriers to counseling multicultural children and Eurocentric play therapy techniques with multicultural populations are highlighted. Specific guidelines and examples for play therapy with multicultural children are provided. Recommendations and implications for mental health professionals are also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
18.
We address the problems of noise and huge data sizes in microarray images. First, we propose a mixture model for describing the statistical and structural properties of microarray images. Then, based on the microarray image model, we present methods for denoising and for compressing microarray images. The denoising method is based on a variant of the translation-invariant wavelet transform. The compression method introduces the notion of approximate contexts (rather than traditional exact contexts) in modeling the symbol probabilities in a microarray image. This inexact context modeling approach is important in dealing with the noisy nature of microarray images. Using the proposed denoising and compression methods, we describe a near-lossless compression scheme suitable for microarray images. Results on both denoising and compression are included, which show the performance of the proposed methods. Further experiments using the results of the proposed near-lossless compression scheme in gene clustering using cell-cycle microarray data for S. cerevisiae showed a general improvement in the clustering performance, when compared with using the original data. This provides an indirect validation of the effectiveness of the proposed denoising method.  相似文献   
19.
In this paper, we describe a comprehensive layout methodology for bonded three-dimensional integrated circuits (3D ICs). In bonded 3D integration technology, parts of a circuit are fabricated on different wafers, and then, the wafers are bonded with a glue layer of Cu or polymer based adhesive. Using our layout methodology, designers can layout such 3D circuits with necessary information on inter-wafer via/contact and orientation of each wafer embedded in the layout. We have implemented the layout methodology in 3DMagic. Availability of 3DMagic has led to interesting research with a wide range of layout-specific circuit evaluation, from performance comparison of 2D and 3D circuits to layout-specific reliability analyses in 3D circuits. Using 3DMagic, researchers have designed and simulated an 8-bit encryption processor mapped into 2D and 3D FPGA layouts. Moreover, the layout methodology is an essential element of our ongoing research for the framework of a novel Reliability Computer Aided Design tool, ERNI-3D.  相似文献   
20.
现代通信系统电源设计   总被引:1,自引:0,他引:1  
通信设备使用的电源器件有很多种,从前端的功率因数校正(PFC)AC/DC电源到后端的高效DC/DC模块和负载点(POL)转换器,不一而足。从需要很高效率的中间总线转换器(IBC),到那些日趋细小轻巧的VoIP数字电话,以及要求多路紧密调节电压(7~13路输出)的数字用户线(xDSL)电源等,DC/DC电源在现代通信中获得了广泛应用。  相似文献   
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