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排序方式： 共有158条查询结果，搜索用时 20 毫秒
111.
平遥双林寺彩塑是一种以佛教为题材、世俗形象的民间艺术。彩塑塑造方法虽然也是写实主义,但却有独特的塑造风格,民间艺人采用夸张的曲线线条来体现一种力量型的另类曲线美感。以天王殿四大金刚及著名的千佛殿里韦驮做主要的观察对象,探讨了平遥双林寺彩塑独特的塑造技术和对线条音律的运用能力。 相似文献
112.
Philip Irvin 《Journal of the American Water Resources Association》1986,22(4):597-599
ABSTRACT: The annual distribution of flow in a drainage basin within a given region is a function of many factors. These may include annual distribution of rainfall, basin orientation, ground cover, or presence of glaciers. Since the North Cascades region of northern Washington State has little variation in precipitation distribution by month, and the region has significant snowpack, one would predict that in an unregulated basin, basin elevation would be one of the most important factors impacting an annual hydrograph distribution. Such a prediction can be made since the higher a drainage basin is, the larger the portion of runoff that would occur as late spring snowmelt. Given that there is a relationship between elevation distribution and annual hydrograph, the problem becomes one of how to use this relationship to model an ungaged basin's hydrograph. This study concludes that, within the North Cascades region and perhaps within other regions, an effective method of determining annual flow distribution is to model ungaged flows in the same manner as flows from a gaged basin with an elevation distribution similar to that of the subject basin. 相似文献
113.
Recep Ekiciler Muhammet Samet Ali Çetinkaya Kamil Arslan 《International Journal of Green Energy》2020,17(10):555-567
ABSTRACT Al2O3/water nanofluid has been numerically examined for the first time with different nanoparticle shapes including, cylindrical, blade, brick, platelet and spherical, on the flat and triangular-corrugated impinging surfaces. The volume fractions of 1.0%, 2.0% and 3.0% nanoparticles have been used. The Reynolds number is between 100–500 depending on the slot diameter. The finite volume method is utilized to determine the governing equations. The study is analyzed to determine how the flow features, heat transfer features and entropy production were affected by the diversity of nanoparticle shape, nanoparticle volume fraction, and shape of impinging surface. Darcy friction factor and Nusselt number are studied in detail for different conditions. The temperature contours are presented in the case of different nanoparticle volume fractions, nanoparticle shapes and both impinging surfaces. The results of the study suggest that the nanoparticle shape of the platelet shows the highest heat transfer development due to the thinner thermal boundary layer. Heat transfer augments with increasing volume fraction of nanoparticles. In addition, the study is consistent with the results of the literature on heat transfer and flow properties. 相似文献
114.
Characteristics of high-sulfate wastewater treatment by two-phase anaerobic digestion process with Jet-loop anaerobic fluidized bed 总被引：2，自引：0，他引：2
A new anaerobic reactor, Jet-loop anaerobic fluidized bed （JLAFB）, was designed for treating high-sulfate wastewater. The treatment characteristics, including the effect of influent COD/SO42 ratio and alkalinity and sulfide inhibition in reactors, were discussed for a JLAFB and a general anaerobic fiuidized bed （AFB） reactor used as sulfate-reducing phase and methane-producing phase, respectively, in two-phase anaerobic digestion process. The formation of granules in the two reactors was also examined. The results indicated that COD and sulfate removal had different demand of influent COD/SO4^2- ratios. When total COD removal was up to 85%, the ratio was only required up to 1.2, whereas, total sulfate removal up to 95% required it exceeding 3.0. The alkalinity in the two reactors increased linearly with the growth of influent alkalinity. Moreover, the change of influent alkalinity had no significant effect on pH and volatile fatty acids （VFA） in the two reactors. Influent alkalinity kept at 400-500 mg/L could meet the requirement of the treating process. The JLAFB reactor had great advantage in avoiding sulfide and free-H2S accumulation and toxicity inhibition on microorganisms. When sulfate loading rate was up to 8. 1 kg/（m^3.d）, the sulfide and free-H2S concentrations in JLAFB reactor were 58.6 and 49.7 mg/L, respectively. Furthermore, the granules, with offwhite color, ellipse shape and diameters of 1.0-3.0 mm, could be developed in JLAFB reactor. In granules, different groups of bacteria were distributed in different layers, and some inorganic metal compounds such as Fe, Ca, Mg etc. were found. 相似文献
115.
Xanel Vecino Rosa Devesa-Rey Salvador Villagras Jose M. Cruz Ana B. Moldes 《环境科学学报(英文版)》2015,38(12):158-167
In this work a comparative bioadsorption study between a biocomposite consisting of hydrolysed vineyard pruning waste entrapped in calcium alginate spheres and non entrapped vineyard residue was carried out.Results have demonstrated that the biocomposite based on lignocellulose-calcium alginate spheres removed 77.3% of dyes,while non entrapped lignocellulose eliminated only removed 27.8% of colour compounds.The experimental data were fitted to several kinetic models(pseudo-first order,pseudo-second order,Chien–Clayton model,intraparticle diffusion model and Bangham model); being pseudo-second order the kinetic model that better described the adsorption of dyes onto both bioadsorbents.In addition,a morphological study(roughness and shape) of alginate-vineyard biocomposite was established under extreme conditions,observing significant differences between hydrated and dehydrated alginate-vineyard biocomposite.The techniques used to carry out this morphological study consisted of scanning electron microscopy(SEM),perfilometry and 3D surface analysis. 相似文献
116.
防风网气动特性参数的试验研究 总被引：4，自引：0，他引：4
防风网气动特性参数是防风网结构设计中的重要参数.通过风洞试验的方法研究了透风率分别为29.9%和35.4%的蝶形、平板两类防风网的静力风荷载气动特性参数.结果表明,防风网风载体型系数背风面为负值,其绝对值远大于迎风面;迎风面风载体型系数,当透风率较小时为负值,较大时为正值,即防风网向后的吸力是主要作用力. 防风网的压力损失系数、风载体型系数和阻力系数相互紧密联系,其值具有一致性,随着前者的提高,后两者的值也提高,即防风抑尘效果越好,抗风安全性越差.防风网结构设计时,要统筹兼顾,权衡利弊,选其最佳结合点. 相似文献
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118.
醇和酚类等有机化合物作为重要的工业原料,广泛应用于医药卫生、有机合成、食品工业等领域,但生产中排放于环境的这些物质,会对生物造成一定的毒性作用。为建立包含醇和酚类有机污染物对欧洲林蛙蝌蚪及梨形四膜虫毒性的定量结构-活性相关性模型,计算了227种有机污染物的分子连接性指数和分子形状指数,优化筛选了分子连接性指数的0X、1X、2X、4X和5Xc、分子形状指数的K1和K2共7种参数,将这7种结构参数作为神经网络输入层变量,110种有机污染物对欧洲林蛙蝌蚪的毒性值作为输出层变量,采用7:8:1的网络结构方式,构建了令人满意的对欧洲林蛙蝌蚪毒性的神经网络预测模型,方程总相关系数r为0.988,毒性预测值与实验值之间的平均误差为0.14。为检验指数的普适性,同样用这7个结构参数与117种醇和酚类化合物对梨形四膜虫的毒性进行分析,所得神经网络模型的总相关系数达到0.997,对梨形四膜虫毒性的预测值与实验值之间的平均误差仅为0.065,结果表明,所建模型具有良好的预测有机污染物对林蛙蝌蚪及梨形四膜虫急性毒性的能力。 相似文献
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120.