弧型齿残膜捡拾滚筒捡膜的机理   总被引：20，自引：1，他引：20  

陈发  史建新  王学农  赵海军 《农业机械学报》2006,37(6):36-41

对弧型齿残膜清理滚筒捡膜齿的轴向排列、滚筒转速、捡膜齿运动轨迹和各相关参数进行分析研究,初步找出弧型捡膜齿满足要求的排列布置、滚筒转速和合理的入土深度,确定了残膜回收机具的运动参数λ范围,为残膜清理滚筒的设计提供了理论依据。试验表明,所设计的残膜回收机具运动参数是合理的,在保证膜土分离效果好和较高残膜捡拾率的前提下可显著提高工作效率。  相似文献   

厌氧消化物对西瓜的促生抑病作用     

沈德中  周静茹 《中国沼气》1995,13(2):4-7

本文研究了厌氧消化物（沼液和沼渣）对西瓜生长和西瓜枯萎病的影响。用沼液浸种，浓度为０．５％～５％时均可提高发芽率，以２％沼液与８小时浸泡时间为最佳组合，大于５％时降低发芽率。用沼渣与土壤混合，比例为１：５，１：７，１：１０时西瓜生长的各项指标均高于对照，以１：５为最佳；１：３时各项指标与对照相差不多；１：２时各项指标低于对照。沼渣与土壤混合后可抑制西瓜枯萎病，沼渣用量越大抑制作用越明显。当比例为１：７，１：５，１：３时，防效分别为１８％，５８％和８６％。病害发生后用沼液灌根可阻止西瓜枯萎病发展，但没有治疗作用。  相似文献   

旱地全膜双垄沟残膜捡拾机的设计   总被引：1，自引：0，他引：1  

王波  韩正晟  王松林  戴飞  高爱民 《农机化研究》2015,(7):109-112

针对我国西北旱地全膜双垄沟残膜捡拾机仿形能力差、拾净率低的问题,设计了一种旱地全膜双垄沟滚筒式残膜捡拾机。同时,阐述了整机结构及工作原理,并通过机构分析和计算确定了关键部件工作参数,旨在为残膜回收提供一种新的机具。  相似文献   

沼肥对水稻增产作用的研究   总被引：1，自引：0，他引：1  

张福星  张蚕生 《中国沼气》1992,10(3):15-18

本文根据本所4年沼肥肥效定位试验结果,证实沼气发酵剩余物是一种缓速兼性的优质有机肥料。不仅沼液、浮渣、沉渣单独施用对水稻有较为显著的增产作用,而且沼液、浮渣、沉渣合并施用对水稻的增产作用更为显著,因此,必须纠正某些地方“弃渣用液”或“弃液用渣”的片面施用沼肥的现象,大力提倡全沼肥的合理施用。  相似文献   

反相高效液相色谱法测定黄瓜和梨中阿维菌素B1a残留   总被引：2，自引：0，他引：2  

张红艳  王玉红  赵玉珍  王成菊  李学锋  邱立红 《农业环境科学学报》2007,26(3):1085-1087

利用反相高效液相色谱法研究建立了蔬菜（黄瓜）与水果（梨）中阿维菌素残留量的测定方法。样品采用甲醇提取，二氯甲烷萃取，经弗罗里硅土柱净化，最后用甲醇定容。色谱柱为C18不锈钢柱（25cm×4.6mm，10μm），流动相甲醇＋水=90＋10（V＋V），流速为1.0mL·min^-1，检测波长为245nm，采用外标峰面积进行定量。结果表明，阿维菌素在0.05～5.00mg·L^-1范围内呈良好的线性关系（r=1.0000），方法的添加回收率范围为82.99%～92.23%，变异系数为2.31%～4.15%，最小检出浓度为0.001mg·kg^-1，能够满足对该农药在黄瓜和梨中残留分析的要求。  相似文献   

间接竞争性ELISA检测甲胺磷残留   总被引：5，自引：1，他引：5  

董国伟  刘贤进等 《华中农业大学学报》2001,20(5):434-437

采用制备的兔抗血清建立了甲胺磷（methamidophos,MTP)残留的间接竞争性ELISA方法，证明了抗血清的特异性较好，并确立了测定参数：抗血清与包被抗原的最佳工作浓度分别为1：3000和1：5000；最适检测范围为0．01－0．1μg/ml；批内变异系数7．56％，批间变异系数5．70％。  相似文献   

The Nutrient Quality of Cassava by Addition of Cow Rumen Fluid Enzyme     

S. Sandi  E. B. Laconi  A. Sudarman  K. G. Wiryawan  D. Mangunwijaja 《农业科学与技术》2011,(8):1122-1125

  相似文献   

Effect of Water and Rice Straw Management Practices on Soil Organic Carbon Stocks in a Double-Cropped Paddy Field     

《Communications in Soil Science and Plant Analysis》2012,43(18):2330-2342

ABSTRACT

Water and rice straw (RS) management practices can potentially affect the accumulation of soil organic carbon (SOC) in agricultural soils. Field experiments were conducted in two consecutive rice-growing seasons (wet and dry) to evaluate SOC stocks under different water (continuous flooding [CF], alternate wetting and drying [AWD]) and RS management practices (RS incorporation [RS-I], RS burning [RS-B], without RS incorporation and burning [WRS]) in a double-cropped paddy field. RS-I under AWD had higher volumetric water content than the same RS management under CF at tillering in both growing seasons. Total SOC was significantly higher under AWD at tillering in both wet and dry seasons and after harvesting in the dry season compared with CF. The same trend was also observed for C:N ratio at tillering and after harvesting in the dry season. RS-B plots had lower SOC stocks than RS-I and WRS plots across most of the measuring periods regardless of the growing seasons. SOC stocks were 33.09 and 39.31 Mg/ha at RS-B and RS-I plots, respectively, in the wet season, whereas the respective values were 21.45 and 24.55 Mg/ha in the dry season. Incorporation of RS enhanced SOC stocks under AWD irrigation, especially in the dry season before planting. Soil incorporation of RS in combination with AWD could be a viable option to increase SOC stocks in the double-cropped rice production region as it is strongly linked with soil fertility and productivity. However, the environmental consequences of RS incorporation in irrigated lowland rice production system should be taken into consideration before its recommendation for paddy field on a large scale.  相似文献   

气相色谱法测定水果中咪鲜胺残留量的方法研究     

郑雪虹  吕岱竹  谢德芳  冯信平  林靖凌 《热带作物学报》2012,32(8):43-48

采用丙酮震荡提取样品，在水解衍生的步骤中创造性地使用试管加入吡啶盐酸盐，于220℃的烘箱里水解1.5 h，经过处理后使用气相色谱ECD进行测定。结果表明：该方法的线性范围为0.005～0.500 ng，相关系数为0.999 9；对香蕉、绿橙、花牛苹果、青苹果、猕猴桃、砀山梨6种空白基质分别进行了0.01、0.10、1.00 mg/kg 3个水平加标，其回收率为81.0%～106.4%，相对标准偏差(RSD，n＝5)为0.3%～5.7%；该方法的最低检出限为0.01 mg/kg，并且烘箱水解的新方法操作简便  相似文献   

Pyrethroid insecticide residues on vegetable crops     

Ripley BD  Ritcey GM  Harris CR  Denommé MA  Brown PD 《Pest management science》2001,57(8):683-687

Pyrethroid insecticides were applied on various vegetable crops as foliar treatments to determine dissipation rates. On Chinese broccoli (Guy Lon), Chinese mustard (Pak Choi) and Chinese cabbage (Kasumi, napa), fenvalerate was persistent with residues of 0.10, 0.14 and 0.11 mg kg-1, respectively, by day 21. Cypermethrin residues on head lettuce were below 0.1 mg kg-1 by day 10 but on the leafier romaine and endive varieties it was more persistent and required 14-19 days to dissipate below this concentration. After three applications, residues of cypermethrin in harvested carrots and of permethrin in eggplant were not detected on the day of application. On asparagus, deltamethrin and cypermethrin residues declined to less than 0.1 mg kg-1 by days 1 and 2, respectively; permethrin was more persistent, requiring more than 2 days to decline to less than 0.1 mg kg-1. Deltamethrin on dry (cooking) and Spanish onions was not detected on the day of application. On tomatoes, the concentration of permethrin was 0.093 mg kg-1 on the day of application and declined to about 0.05 mg kg-1 after 2-4 days. In general, permethrin, cypermethrin and deltamethrin residues declined to acceptable concentrations within an acceptable pre-harvest interval. Fenvalerate may be too persistent on these speciality crops unless a maximum residue limit > 0.1 mg kg-1 is permitted.  相似文献