氧化乐果和阿维菌素对大叶黄杨叶表蜡质层的影响     

马永亮  杨玉武  曲爱军 《林业科技》2006,31(4):28-29

选用阿维菌素和氧化乐果喷施到大叶黄杨上,利用氯仿法测定了大叶黄杨叶表的蜡质含量。其结果表明,供试农药对大叶黄杨叶表蜡质层含量均有显著影响,其中以阿维菌素影响较大,氧化乐果影响较小。  相似文献   

软弱层带抗剪强度经验公式   总被引：6，自引：0，他引：6  

刘宏力石豫川  刘汉超 《水土保持研究》2005,12(6):39-41

软弱层带是控制岩体稳定性的重要边界条件。软弱层带的工程特性是其物质基础与环境条件共同作用的结果。研究表明软弱层带的抗剪强度与塑性、干密度和含水量具有明显的相关性，并提出了抗剪强度与三因子之间的经验公式。  相似文献   

基于多层感知器神经网络对遥感融合图像和TM影像进行土地覆盖分类的研究   总被引：4，自引：0，他引：4  

吴连喜  严泰来  张玮 《土壤通报》2001,32(Z1):33-36

８０年代以来，人工神经元网络（ＡＮＮ）技术的应用不断向广度和深度发展．用不同空间分辨率的ＴＭ和ＩＲＳ遥感图像进行融合，综合了不同传感器数据所提供的信息，增强了图像的清晰度，改善了解译效果。用多层感知器神经网络对遥感融合图像进行分类，分类精度达９５％，比用多层感知器神经网络对ＴＭ图像进行分类（分类精度达７３％）效果要好．  相似文献   

杂交水稻制种建立母本最佳穗层结构的探讨   总被引：3，自引：1，他引：2  

杨孚初 《杂交水稻》1997,12(2):7-9

将制种田中喷施“九二０”后的母本穗层划分为高层穗、表层穗、平颈穗、包颈穗４个层次。对各种类型穗层的受粉原理、自然受粉状态，与结实率的关系进行了研究分析，提出了母本最佳穗层结构模式，以及在实践中可以采取稀播壮秧、密植等６项农艺措施和配套措施，来建立起母本最佳穗层结构  相似文献   

生物纤维饲料在蛋鸡生产中的应用研究   总被引：1，自引：0，他引：1  

王淑萍  崔鹏飞等 《家畜生态》2002,23(3):11-13

生物纤维饲料是对玉米淀粉湿磨国工过程中的浸泡液，黄浆和玉米皮渣等副产品经生物发酵方法而形成的一种新型饲料。本文研究了生物纤维饲料在蛋鸡饲养中的饲喂效果。试验表明，半风干生物纤维饲料（含水分26．68％）以5％比例添加蛋鸡日粮中的饲喂效果与对照组相比，日均产蛋量提高6．4％，平均产蛋率提高6．05％，料蛋比下降13．01％，毛利润提高90．70％，而风干生物纤维饲料（含水分15．44％），则以10％比添加于蛋鸡日粮时，表现出较明显的增产效果，其与对照组相比，日均产蛋量提高4．04％，平均产蛋率提高4．18％，料蛋比下降4．09％，毛利润提高25．74％。  相似文献   

中国粮食仓储行业淘汰甲基溴行动   总被引：1，自引：1，他引：1  

黎万武  严晓平  周浩  兰盛斌 《粮食储藏》2007,36(2):6-9

为切实履行我国政府对国际社会<关于消耗臭氧层物质的蒙特利尔议定书>的<哥本哈根修正案>所作出的承诺,中国粮食仓储行业在保障我国粮食安全储备的前提下,在"淘汰甲基溴,保护臭氧层"方面采取了一系列行动(包括调研、确定替代技术、培训、制定规程、建设示范库、研究替代技术等),以达到替代甲基溴的目的.淘汰甲基溴的实际行动,研究新的淘汰甲基溴替代技术,对增强人们保护臭氧层的意识,推广和应用替代技术和确保人类共同家园的可持续发展都具有重要的意义.  相似文献   

系祖轮配对维持并提高豫州褐壳蛋鸡Ⅲ系生产性能的研究     

宋素芳  康相涛  李明  王彦彬 《华北农学报》2003,18(2):103-105

对豫州褐壳蛋鸡Ⅲ系采用系祖间轮配的选配方法，经过连续3个世代的选育，开产日龄推迟5．72d，开产平均蛋重减少0．87g，72周龄平均蛋重增加2．82g、蛋数增加8．62枚，蛋品质维持在较高水平，蛋壳颜色变深。说明对已育成的纯系采用系祖间轮配的选配方法，可以维持并提高其生产性能。  相似文献   

Design of Double Layer Torsional Reticulated Shell Using Back- Propagation Neural Network     

WU Yun -fang  Li Zhong -yi  YU Yang 《保鲜与加工》2006,(3):67-70

In this paper artificial neural networks are used for design of large span double layer torsional reticulated shell. The torsional reticulated shells with spans varying between 50.0 - 80.0m are considered, Back -propagation algorithm is employed for training efficient neural networks for evaluation of the maximum deflection, weight and design of double layer torsional reticulated shell. A special method is developed for data ordering to reduce the nonlinearity of data and to increase the speed of training. This approach also provides the necessary stability. It shows that it is feasible to design double layer reticulated shell with artificial neural networks.  相似文献   

Inheritance of tree and fruit characters in progenies from crosses of sweet cherry (Prunus avium L.) cultivars     

Robert Theiler-Hedtrich 《Euphytica》1994,77(1-2):37-44

Summary Approximately 1000 seedlings from 20 combinations crossed in 1979, 1980 and 1981 (Theiler-Hedtrich 1985a) were tested for several characters: fruit set (yield), fruit size, fruit colour, formation of abscission layer and bleeding after fruit removal from fruit stalks, bacterial canker resistance, flowering and harvesting time. From progeny of crosses with Stella as pollinator, 56% (Vittoria × Stella) and 46% (Schüttler × Stella) of the seedlings were self-compatible, of which 14 were high yielding with good fruit size and quality. From the data recorded it can be concluded:fruit set is a recessive character; only 5 to 20% of very good yielding seedlings were obtained in different progeny, even if the parental plants were both very good croppers.Fruit juice and skin colour was in most progenies ‘black’ even if they were from combinations with ‘white’ varieties, e.g., Merton Glory or Schüttler. Only from the combination Schiittler (‘white’) × Stella (‘black’), 50% of the seedlings were ‘white’; Stella therefore is heterozygous for the character of fruit juice and skin colour.Fruit size is evenly distributed in progeny with respect to the fruit size of their parent plants.Abscission layer formation and non-bleeding is a genetically complex character. In combinations where both parent plants formed fruits with complete abscission layers and which were not bleeding after fruit removal from the stalk, this character was inherited only to 50% (Vittoria × Schüttler) or 85% (Vittoria × Frühe von der Weid) in the progeny. For the genetical control of this character further studies are necessary.Bacterial canker susceptibility was evenly distributed in seedlings from all combinations even if the highly resistant cv. Vittoria was used as one parent plant, thereby not confirming the expected results of a higher proportion of resistant seedlings from combinations with Vittoria.Flowering and harvest time of the seedlings from different combinations was within the range of the parent plants. Only in the combination of Vittoria × Stella (mid-to late-ripening season) one seedling out of 99 was found to form ripe fruits two weeks earlier than the parental plants. From the seedlings tested 40 have been chosen for further evaluation or genetical studies.  相似文献   

几个水稻品种的种子蛋白超薄等电聚焦谱带的差异   总被引：1，自引：0，他引：1  

胡群宝  夏清华  陈森  罗森辉  蔡雪莉  蔡惠娇  何德银 《种子》2003,(5):49-50

利用超薄等电聚焦技术对6个水稻品种种子贮藏蛋白进行了分析，发现供试水稻品种间的谱带有差异，据此差异，能有效区别6个水稻品种。  相似文献