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81.
The green is as a symbol of no pollution,no public harm and environmental protection. The green automobile is the inevitable results that the automobile technique continuously developes. A new style vehicle--the green automobile is the urgent solicit of environmental protection is developed. The automobile industry can develop continuously. This article mainly discusses the importance of the green auto_mobile's research and development,the development status in quo and prospect of the green auto_mobile technique in the world,and states the relationship between the green automobile technique and environmental protection from green technical system theoretically clarify the study of green automobile,including its design and the system,the manufacture and its technology,the energy,the rebuild engineering and a series of subjects. How to evaluate the cycle and the evaluable mark of the green automobile,the prospect of green automobile are pointed out. 相似文献
82.
83.
The following details are discussed in the present paper, after high titanium slag and H3PO4 is put in the closed system,the .reaction takes place under controlled temperature conditions, and the gas produced is collected. The two phases of gas liquid attain kinetic equilibrium, ihe gas above the liquid is used to make GC analysis with the aid of chromatographic column of 5A molecular sieve, TCD and N2 30ml/min. Satisfactory quantitative results can be achieved with simple instruments and uncomplicated operation technique. 相似文献
84.
This paper presents the application of sand-gravel-cushion technique in thefoundation of mountainous area inhomogeneity and analyges non-uniformity of the foundation inmountainous,It is different from the traditional theory of sand-cushion,This is a new developmentand able to make a full use of the rock debris fill and the combinational soil-rock foundation in the mountainous areas. 相似文献
85.
In the course of searching immunodulators from natural herbal sources,the polysaccharide has been isolated from the water extract of duckweed(Herba Spirodelae seu Lemnae).The authors aim at investigating the methods that determine the content of total saccharides in the mixture,accordingly,to be used as a quality control in the procedure of producing polysaccharides from duckweed.The contents of saccharides in the extraction were mensurated by spertrophotometry of sulphuric acid-phenol and sulphuric acid-anthrone.And the validitiy of methods was evaluated through some indexes such as linearity and range,precision,stability,and accuracy.The results reveal the methods are convenient,rapid,accurate,and high sensitive,thereby leading to a wide and effective use in determining the saccharides contents in polysaccharides extraction from Herba Spirodelae seu Lemnae. 相似文献
86.
The author introduces a method and experimental procedures that determine dn/dc,molecular weight and its distribution of the hyroxyethyl starch(HES) by means of Gel Permeation Chromatography-Refractive index-Multi-angle laser light scattering detection(GPC-RI-MALLS)techniques.The key experimental technique and results are discussed.The method takes CH3COOH/CH3COONa as mobile phase and solvent.The experiment gets satisfactory results.It can be used as a routine method to determine the hyroxyethyl starch(HES) molecular weight and its distribution. 相似文献
87.
Zen Fanqi Gu Yuasheng Zen Xianglin 《保鲜与加工》1993,(4):136-143
Based on the network planning model developed by the author for an overhaul project of a rolling mill production line in a heavy steel plant, an new multiobjective network planning model is proposed in this paper. The formulations of network time parameters are derived. The optimization problem of multiobjective network planning is also discussed. And it has been found out that the fractional single-objctive network is only one of the cases in this model. 相似文献
88.
高产优质商品玉米生产模式:—三种遗传效应集成利用(TEU) 总被引:3,自引:0,他引:3
通过大量详实资料,对玉米杂种优势、雄性不育,油分基因花粉直感等3种遗传效应的研究现状作了详细概述,根据相关的遗传理论与实践,提出了将三种遗传效应进行技术集成的可能性,从而形成一种高产高油玉米生产模式,有可能是未来玉米生产的发展方向。 相似文献
89.
The 99% of all microorganisms in naturecannot be isolated by standard culture methods without conspicuous external characters to classify them morphologically. In addition, classification based on physiological or biochemical features are often fuzzy. Molecular techniques are used for uncultured microorganisms to explore the diversity of microbial communities and novel resources without the need of cultivation. DNA dynamics and cloning of PCR products obtained from environmental DNA is now routinely used to identify microbial populations in microbial ecology. For practical reasons the approach is not suited to study the complex dynamics of microbial communities in environment. Genetic fingerprinting techniques are better tools, which give complement for the traditional microbiological methods. The methods are rapid and relatively easy to perform, and they allow the simultaneous analysis of multiple samples, which makes it possible to compare the genetic diversity of microbial communities from different habitats, or to study the behaviour of individual communities over time. 相似文献
90.
本文通过聚集度指标(如:C、K、C_A、I、I_δ、)测定,以及Iwao’线性回归、Taylor’sS ̄2一回归和格局纹理分析,结果表明,棉花烂铃空间格而在一切密度下都呈聚集型,且聚集强度随烂铃密度的升高而增加,其空间格局的基本成分是疏松的个体群,其大小约为2~5株棉花,平均约含2.84个烂铃个体,且个体群内的个体呈随机分布,经μ检验和方差分析,双对角线5点式、棋盘式和平行跳跃式等3种取样方法均适用于棉花烂铃田间调查,尤以双对角线5点式为佳,用双对角线5点式应样法调查的最适抽样数:一般病情普查至少10个样方(每样方系5株棉花),系统测报和科研调查为20~30个样方。最后给出了棉花烂铃平均密度的零频率简易估计模型。 相似文献