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51.
土石过水围堰过水期最不利工况及其流量确定 总被引:7,自引:0,他引:7
本文系统分析了影响土石过水围堰溢流工况的主要因素,提出衡量最不利工况的指标和确定员不利流量的方法,为土石过水围堰堰体下游护坡结构及消能防冲设施设计提供了理论依据。通过理论计算结果与模型试验现场观测资料数据对比分析,说明提出的过水期最不利流量判别方法是符合实际情况的。 相似文献
52.
A three-dimensional model was developed to investigate the influence of various hot filaments parameters on substrate temperature fields that significantly affect the nucleation and growth of diamond films over large area by hot-filament chemical vapordeposition (HFCVD). Numerical simulated results indicated that substrate temperature varies as a function of hot filamentsnumber, radius, temperature, emissivity, the distance between filaments, and the distance between substrate and filamentsarrangement plane. When these filaments parameters were maintained at the optimal values, the homogeneous substrate temperature region of 76 mm×76 mm with the temperature fluctuation no more than 5% could be obtained by a 80 mm×80 mmhot filaments arrangement plane. Furthermore, the homogeneous region could be enlarged to 100 mm×100 mm under thecondition of supplementary hot filaments with appropriate parameters. All of these calculations provided the basis for speciallyoptimizing the hot filaments parameters to dep 相似文献
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Fertuck Eric A.; Bucci Wilma; Blatt Sidney J.; Ford Richard Q. 《Canadian Metallurgical Quarterly》2004,41(1):13
This study examined the relation between changes in clinical functioning and changes in verbal expression in 81 seriously disturbed and treatment-resistant young adults seen in a comprehensive, psychoanalytically oriented inpatient treatment. Clinical functioning was evaluated with a battery of clinical and social measures. Verbal representations were assessed using computer-assisted scoring of Thematic Apperception Test responses. Changes in the frequency of verbal content and style in the narratives of these patients covaried with changes in clinical functioning. Significantly different covariations of verbal and clinical change, particularly differences in covariates of referential activity, were found for patients with anaclitic versus introjective personality configurations. The implications of these findings for understanding and treating severe psychopathology are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Investigation into polishing process of CVD diamond films 总被引:1,自引:0,他引:1
A new technique used for polishing chemical vapor deposition (CVD) diamond films has been investigated, by which rough polishing of the CVD diamond films can be achieved efficiently. A CVD diamond film is coated with a thin layer of electrically conductive material in advance, and then electro-discharge machining (EDM) is used to machine the coated surface. As a result, peaks on the surface of the diamond film are removed rapidly. During machining, graphitization of diamond enables the EDM process to continue. The single pulse discharge shows that the material of the coated layer evidently affects removal behavior of the CVD diamond films. Compared with the machining of ordinary metal materials, the process of EDM CVD diamond films possesses a quite different characteristic. The removal mechanism of the CVD diamond films is discussed. 相似文献
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Thanapalan Murugesan G. S. Venkat Rathnam S. Panduranga Rao P. Gangadhar Rao 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,63(3):290-294
In the present study of gas–liquid contactors, mean residence/contact time was calculated from knowledge of superficial velocity and the gas phase hold-up, for various gas rates and impeller geometry and speeds, and compared with values obtained from RTD measurements. A new correlation, involving Flow Number, Froude Number, system geometry and the physical properties, is proposed. This uses the authors data and those available in literature. 相似文献
58.
本文用计算机数字模拟方法研究了电活性分子多层Z型L-B膜修饰电极的循环伏安行为。计算了电极与修饰L-B膜分子第一层之间的电荷转移速度常数K_o,L-B膜分子层间的电荷转移速度常数k_i;对峰电位差△E_p及阳极峰面积Q的影响,以及在不同条件下各层分子的氧化态分数随扫描时间的变化。为研究和设计电活性分子修饰电极的实际体系提供了大量数据和信息。 相似文献
59.
水溶性防氧化剂在SMT用印制板上的应用 总被引:1,自引:0,他引:1
水溶性的防氧化剂是一种有机可焊性保护剂。其方法是在印制板完全阻焊、字符层的印刷,并经电检之后,通过表面浸渍在裸铜的贴片位或通孔内形成一种耐热性的有机可焊性膜层。这种有机、可焊、耐热的膜层,膜厚可达0.3-0.5mm,其分解的温度可达约300℃,传统的印制板的热风整平法亦无法满足QFP愈来愈密集的需求,同时也无法满足SMD表面平整度的要求,更无法适应PCB薄型化生产。烷基苯并咪唑的OSP法能弥补这项缺陷,因而在PCB业乃至SMT产业中得到了广泛的应用。 相似文献
60.