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61.
薄荷的快速繁殖与栽培技术的研究 总被引:3,自引:0,他引:3
本文介绍了薄荷的特性、栽培技术及用途,表明它在我们日常生活中起着重要的作用。用薄荷的组织培养方法可加速其繁殖系数,以达到迅速应用的目的。 相似文献
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The influence of the structure and location of dam and weir on fluid flow state in a two-strand tundish is studied, and a set of optimal structure, combining with the average residence time calculated from RTD curve, is obtained. The result indicates that the fluid flow state can be changed and the path of the fluid flow can be prolonged as well as the average residence time is improved after using dam and weir. But there are some dead zones after fluid passed through the dam and weir. Combination scheme of No. one dam and weir is better than the others. Its average residence time is 299 s and the volume fraction of dead zone is 31.0%. After the optimization of flowing control parameters in tundish, the best case is that the distance between dam and weir is 290 mm and the distance between weir and the long nozzle is 383 mm. The longest average residence time is 351 s and the minimum volume fraction of dead zone is 19.0% under the above situation. Compared with that of no dam and weir, the average residence time increases by 65 s and the dead zone volume fraction decreases by 15.0%. Based on Newton formula, the calculated results show that the inclusions with diameter larger than 17.5 μm can float up within 351 s under this optimization situation. 相似文献
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The funneling effect of noise is the main difficulty in two way CATV modification works. This paper discusses the source of noise and interference, the mechanism to form noise funneling, the regularities of distribution, the characteristics of the spectrum, etc. The purpose is to find the way of reducing funnel noise. The invading noise has the greatest effect on the upstream of two way CATV system, which mainly comes from the indoor of the users. The increase of the number of cable modem will not obviously make greater funneling noise. The cable connectors are the main source of producing and invading noise in outdoor cable network, which is a threat to the safty of the whole upstream channel. 相似文献
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Information integrating is the most important key to CIMS,which is the base of the function integrating and all others.Because of so many kinds,so complicated structure,so many different sources and uses that the information in CIMS has,it is necessary to build a popular Information Integrating Model. The model of information integrating in the thesis bases on the enterprise model,which is presented by ISO(International Organization for Standardization).According to the object-oriented method,the process of modeling begins with classifying the information,and then describes the definition of the attributes and the structural relation of those objects. By means of the idea of Encapsulation and Inheritance,the destination of information integrating can be arrive and the model of information integrating can be set up. The model which is based on the share information is helpful to finish the function integrating and the whole CIMS' construction. Moreover,the system which is developed following such program can be reused for many times and the developing circle of CIMS can be apparently shortened,too. 相似文献
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Cai Shaoxi Wu Xi Xiao Jun Liu Yanhai Wu Yunpeng 《保鲜与加工》1992,(3):15-18
This paper describes a part of the experiments concerning the viscoelasticity of human blood, which are based upon the theories lead by the authors. The data from the experiments are compared with those in the literatures. The effect of cell hematocrit on viscoelasticity is especially discussed and a new viscoelasticity index is defined to eliminate this effect. 相似文献
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YANG Zhong-ren RAO Cheng ZOU Jian PENG Zhen-liane Ministry of Education Chongqing Chin 《保鲜与加工》2004,(2):32-35
Dong village is very valuable for research work because of its special regional and national character and rich cultural implication. In this paper, some information about the location, form and features of Dong village is given. Then, the relationship between the culture and the settlement is analyzed, which provides a clue for understanding Dong village and will be beneficial to creating modern human settlements. 相似文献
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In the past, the criterion for calibration has almost invariably been the stellar oriented ballistic camera,the method is a point to point comparison on the identical coordinate system. Deficiencies is follows: The request of weather is severe(cloudless night); The period is often long; the measure equipment of high precision can't be calibrated. While EMBET methods is used in calibration, it does not need criterion and it demands only that the measure elements is larger than 3,and the trajectory and many system errors of the measure elements can be simultaneously calculated with the measure data sequences. The error models of related equipments' measure elements and the EMBET of typical equipment group are given. The EMBET method is successfully used in Accuracy-analysis of Satellite Launch. 相似文献