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141.
Liang Xichang Shao Ming 《保鲜与加工》1993,(1):1-6
The 12 new technologies in gear machining, which have been developed
Chongqing University, have been selected in"The major Extending Plan of National Technological Achievements". Apart from a brief introduction to thise technologies,this paper presents the basic principles and the levels of forming grinding .special shaping gear,sycloidal gear machining and internal gear machining technologies. 相似文献
142.
As a large burning coal country, resolving the SO2 letting problem is the most important thing in the environment protection work. Electric power industry reveals the supply's load rate declining and the discrepancy between apex and vale augments year after year. It makes the load adjustment become an imminency task in the electric power industry. The article popularizes the light power saving technology in the inhabitant living lighting power through reinforcing the DSM technology. It studies the influence on energy and environment after using the technology. It studies avoidable electricity quantity, avoidable electricity power, avoidable apex load, avoidable coal consuming and avoidable SO2 lettling. At last, it makes a concrete analysis with a city's example. 相似文献
143.
144.
CHEN Deng-fu SUN Ming-yue FENG Ke ZHAO Zhan-feng DONG Ling-yan WEN Liang-ying PAN Yan-hua 《保鲜与加工》2004,(9):67-71
A numerical simulation commercial software has been developed by the object-oriented Visual Basic programming language on the basis of the 2D mathematical model of secondary cooling Process in billet continuous casting. Thereby an effective experimenting tool for computer simulation of continuous casting process is gained. By simulation with the software, the caster structures and operating parameters in continuous casting can be designed and optimized. The simulating calculation examples on several casters and its production applications indicate that the commercial software developed has more accuracy, practicability and commonality, as also as simpler operating capability. The simulated results have been successfully applied to the design and production of the high-efficiency modification for several billet casters interiorly. 相似文献
145.
受雨害小麦籽粒物性与吹泡特性相关性分析 总被引:1,自引:0,他引:1
小麦经粒径分级和重力分选,吹泡特征值发生了变化。由于粒径较大的籽粒较易受到雨害,影响其品质,粒径分级后,其吹泡特征值变化显著,分级效果明显。再经重力分选后,从分选出口I~V试样的容重依次增大,并且随着容重增加,吹泡特征值出现不同趋势,分选效果有明显差异。籽粒容重与弹性(P)和配置比(P/L)呈显著正相关,与延伸性(L)和延伸能力(G)呈显著负相关性,而与烘焙强度(W)和弹性指数(Ie)的相关性不明显。采用密度的线性模型描述吹泡特性可达到很高的拟合精度。 相似文献
146.
不同施氮量对秋播超甜玉米产量性状的影响 总被引:2,自引:1,他引:2
摘要:田间试验、常规考种分析6种不同施氮水平对秋播“华珍”超甜玉米产量性状的影响,为超甜玉米种植过程中合理施用氮肥提供科学的指导依据。结果表明:6组不同施氮量对超甜玉米叶面积、穗长、穗粗、穗行粒数、百粒鲜重和百粒干重都有显著的增产效果。其中有效增加促进叶片面积,穗长、穗粗、穗行粒数以及鲜苞产量的最佳氮肥施用量在225kg/hm2~300kg/hm2之间。不同氮肥水平对百粒鲜重和百粒干重也有显著增产效果,最佳施氮量在300kg/hm2~375kg/hm2之间,因此通过调控氮肥的施用量来增加超甜玉米产量是可行的,其中约300kg/hm2的氮肥施用量既能有效提高超甜玉米主要产量性状,降低生产成本,也能避免氮肥施用过多对玉米植株生长以及生态环境造成不良影响。 相似文献
147.
A Coptis Chinesis is the dry rhizoma of ranunculaceous Coptis Chinesis Franch or Coptis deltoidea C. 7. Cheng et Hisao, or Coptis teeta Wall. It is the traditional Chinese herb, which is used in the contagious diseases. In recent years, its new pharmacological actions have been reported, which are antitumour, hypoglycemic response, immunoloregulation, improving the functions of cardiovascular. The important pharmacological functions of Coptis Chinesis are hypoglycemic response, improving the functions of cardiovascular, antitumour. With the deeply researching of Coptis Chinesis pharmacology, and the continuous founding of pharmacological mechanism, new preparation will be widely applied in the clinic. 相似文献
148.
This paper studies the key technology in the 3 - D digital city construction, and puts forward a new method to construct and realize the 3 - D digital city. The authors discuss the dates gathering and disposal from the collection of 3 - D topograph dates, the construction and ingress of 3 - D model, the gathering and disposal of texture dates. Subsequently, to solve the problem of that the 3 - D topograph dates are greater than the 2 - D topograph, the bulk-dates optimization of 3 - D digital city is realized through the choose of appropriate DEM of linenumbers and column numbers, the 3 - D model modeling specification, the using of nodes replace, the optimization of LOD modeling. The successful operation result of Chongqing Hi-tech Development Zone 3 - D digital city project illustrates that, this system can realistic mimic status in quo of the Chongqing Hi-tech Development Zone, the system operates smoothly, and its effect is also well. 相似文献
149.
150.