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71.
水电站施工期水土流失预测   总被引:2,自引:0,他引:2  
肖满  王连俊  冯涛 《东北水利水电》2006,24(7):62-64,66
水电站建设的水土流失问题主要体现在施工期和运行期,并以施工期的影响较为突出.如不采取必要的减免措施,将会对周围生态环境造成无法挽回的损失。本文阐述了水电站建设水土流失的几种常用的预测方法,对水土流失量进行预测,并结合具体工程实例对水电站建设过程中新增水土流失量进行了预测。  相似文献   
72.
Studies conducted on two power-generating units at the Kharanorskaya SAPP relative to the steam-water-oxygen passivation, preservation, and partial cleaning of all boiler-heating surfaces, including the surfaces of the reheater, and passivation of the surfaces of the high-pressure heaters on the steam and water sides by the steam-oxygen method, as well as partial passivation, preservation, and cleaning of turbine blading are presented. __________ Translated from élektricheskie Stantsii, No. 6, pp. 56–64, May, 2006.  相似文献   
73.
李缦 《通用机械》2005,(3):19-20
位于西安高新技术产业开发区的西安超滤(集团)是国内专业从事压缩空气/气体过滤、干爆、分离设备开发,生产和经营的高新技术企业,公司自1994年成立以来,一直致力于气体净化行业的科研,开发,2004年公司迎未了十周年庆典,而2005年是西安超滤发展的新的十年的第一年,近日,本刊记者采访了西安超滤(集团)总经理李大明先生。  相似文献   
74.
1,3,5‐Triglyceratetriazine [first tier (G1)] and tri(1,3,5‐triglycerate) triazine [second tier (G2)] dendrimers were prepared with 1,3,5‐trichlorotriazine and sodium glycerate in a 1 : 3 mass ratio in an ethanolic medium.G1 and G2 were amorphous, white, solid substances. Their structures were elucidated with IR, 1H‐NMR, and 13C‐NMR, and their thermal stability was studied with thermogravimetric analysis. The activation energy was calculated with the Freeman–Carroll model. Densities, viscosities, and surface tensions for 0.01–0.08 mol/kg aqueous solutions increased at 0.01 mol/kg for sodium glycerate, 1,3,5‐trichlorotriazine, 1,3,5‐triazine triglycerate chloride, G1, and G2. These values were measured at 298.15 K. The apparent molal volume, reduced viscosity, and inherent viscosity were calculated from the densities and viscosities, respectively. The data were regressed for the limiting densities, limiting apparent molal volumes, intrinsic viscosities, limiting inherent viscosities, and limiting surface tensions for solute–solvent interactions. The positive limiting apparent molal volume values were noted in the order of G2 > 1,3,5‐triazine triglycerate chloride > G1 > 1,3,5‐trichlorotriazine > sodium glycerate, with weaker hydrophilic intermolecular interactions of G2. The higher intrinsic viscosity and limiting inherent viscosity values for G2 implied stronger G2–H2O hydrophilic interactions, and the higher limiting apparent molal volume of G2 indicated slightly higher dynamic conformational changes in comparison with G1, with stronger structural activities. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
75.
青花装饰是景德镇的传统装饰方法之一,其中的写意青花又以其简约萧疏的艺术特征获得了人们的普遍喜爱。针对时代的变化影响,研究了当今写意青花在题材选择上与传统写意青花的差异。  相似文献   
76.
Po  L.M. Tan  W.T. Wong  W.B. 《Electronics letters》1995,31(23):1988-1990
A new colour quantisation and quadtree based image compression scheme is proposed. The features of the new scheme are that colour palette ordering and requantisation of the decoded image for palette-based monitor displays are not required. Thus, fast decoding and displaying can be achieved  相似文献   
77.
78.
The interaction of a soliton of the Nonlinear Schrodinger Equation (NSE) with a weak sinusoidal wave packet is treated analytically. The second-order soliton solution containing the original soliton and a perturbing soliton is expanded to first order in the amplitude of the perturbating soliton. From this expansion, one obtains the associate function of Gordon (1992) and a continuous change of position and phase of the perturbed soliton. One finds that the soliton experiences a second-order change of velocity under the influence of the perturbation. This result is then used to derive the displacement due to a wave packet of general shape, which is also confirmed by computer simulation  相似文献   
79.
Plasmapropertiesoflaser-ablatedSttargetinairWangXiang-Tai(王象泰);ManBao-Yuan(满宝元);WangGong-Tang(王公堂);FanXi-Jun(樊锡君);WangJun(王军)...  相似文献   
80.
The tail-flick (TF) technique was used to assess the antinociceptive properties of nifedipine (NIF) given intraperitoneally (i.p.). First, the most suitable intensity of the noxious stimulus (temperature of the bulb) has been ascertained and used in the main study. Male Sprague-Dawley rats received NIF, dissolved in dimethyl sulfoxide (DMSO) at the doses of 0.0, 0.5, 2, 5, 10 and 15 mg/kg, or control with no injection. For the main study, the noxious stimulus was limited to 15 sec (cut-off time) and TF latencies were recorded up to 120 min. The antinociceptive response was expressed as the area under the curve for each rat and analyzed by one-way ANOVA. The antinociceptive response to the lower doses of NIF (0.5 and 2 mg/kg) did not differ from control (no injection) and DMSO alone. Significance was found at 5, 10 and 15 mg NIF with no difference among the doses. However, there was an increasing tendency of the mean values from 0.5 to 15 mg NIF resulting in a positive correlation. The correlation coefficient was 0.32483 (p = 0.015) and regression equation Y = (19.37) x dose + 1320. Our data suggest that spinal mechanisms are involved in NIF-induced antinociception.  相似文献   
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