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1 接穗采集于优良品种母树上 ,选生长健壮、叶片浓绿、芽眼饱满、无病虫害、树冠外围中上部的 1年生枝条为接穗。采前 10天左右 ,去掉母穗枝条上端幼嫩部分或花穗 ,促进腋芽饱满。接穗最好随采随用 ,剪穗应在晴天露水干后进行 ,采下的接穗应立即剪去叶片和末端幼嫩部分 ,仅留短叶柄护芽 ,剪后立即用塑料薄膜包裹 ,并挂上标签 ,注明品种、日期和地点。接穗用塑料薄膜包裹放在室内阴凉处 ,每天解膜透气半小时左右 ,可贮藏 6天。如贮藏期超过 6天 ,可用湿润河沙分层贮藏 ,上面覆盖稻草 ,保湿防寒 ,每隔 3天翻堆检查接穗和河沙的干湿度。从外地… 相似文献
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晚熟龙眼“松风本”系莆田县经济作物技术推广站于 1 982年举行全区龙眼优良品种鉴评会上发现的实生变异单株。 1 988年《晚熟龙眼优良单株“松风本”试验示范》项目由县科委立项 ,莆田县经作站、莆田县黄石镇农技站、莆田县科委、莆田市果树分所协作攻关 ,在黄石镇七境村建立 0 6 7hm2“松风本”示范试验园 ,开展试验研究工作 ,同时在漳州市、厦门集美、泉州市、福清市、闽候县、霞浦县及广东阳春市、云南思茅地区进行区试。 1 998年 9月 2 5日由福建省农作物品种审定委员会组织鉴定 ,1 999年 3月 1 7日经福建省农作物品种审定委员会审… 相似文献
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An algorithm of fault section diagnosis based on topology identification for distribution networks is presented. By decomposing the topologic matrix which describing the distribution network into two parts,one part only contain the complex coupling factor ,and the other ignore the complex coupling factor. Using this method, the fault zones in distribution network can be identified and isolated efficiently, and the vertexes of the zones can also be identified automatically. This approach adapts to the changefully network structures. 相似文献
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In this paper, the complex method of the nonlinear programming is used to optimize the parameters of energy dissipation bracing in energy dissipation braced frame. This method is realized with computer program and proved to be efficient. A 6-story reinforced concrete frame is used as a demonstrative example. 相似文献
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Based on analyzing about blasting mode of slope in the construction of road, the paper shows that pre splitting blasting is mostly suitable in the section of severely weathering soft rock with developed joints and fractures, introduced the laying out about the hole of pre splitting blasting that can apply in the high slope of the expressway in the section, and designed the parameter. The practice shows that it gained favourable effect by this method. 相似文献
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Product design is a procedure that enterprises meet the needs of consumers; conceptive design is one of the steps in product design and it directly considers requirements of consumers. So how to supply consumers with satisfying function is the essential point. On the basis of function analysis of Value Engineering, the paper puts forward a new method to exercise function definition and function analysis, implements conceptual product design procedure with database techniques.A new way is gotten to convert requirements to conceptual product. 相似文献
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According to existent problems on design and application of the cylindrical cam mechanism with the slide roller-follower, the one correct concept about profile design and pressure angle is presented. Based on this concept, the theoretical profile,practical profile,meshing surface equations and pressure angle formula of the cam mechanism are built up by using opp.rotation analysis and offset surface principle. This method is very simple and clear, and avoids the abstract analysing process in meshing principle. The mathematic models built by this paper can be used to design,manufacture and check this type of cam mechanism correctly, and also create conditions to make deeply meshing property analysis of this mechanism. 相似文献
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This paper investigates the coordinated operation of the progress planning with the resource planning when carrying out engineering projects and puts forward a method of "RSM" under the resource limit conditions. Then, the "RSM" was improved to avoid complicated calculation. This method not only reduces the calculating work by hand but saves computer's memory as well, making the time-resource optimization work more quick and convenient. 相似文献
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The Lexicographic method has subjective and empirical character,so a weighting coefficient is introduced by considering the importance and proportion of each individual object,the preferable result of every individual object can be confirmed by comparing the degree of similarity between the perfect one and the ecumenic one and the Fuzzy optimization will be perfect.The effectiveness of these methods is illustrated by a fuzzy optimal design of the three-bar truss. 相似文献
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Bill of material of product is data about product structure, and plays an important role in product information management. The paper analyzed characteristics of product BOM, and put forward a product BOM management method based on single layer BOM, witch can well meet requirements of product BOM. 相似文献