基础饲粮添加凹凸棒石粉对蛋鸡生产性能的影响

在基础饲粮中添加不同比例的凹凸棒石粉,观察其对蛋鸡生产性能的影响,结果表明,与对照组相比,基础饲粮＋1．5％凹凸棒石粉处理组入舍母鸡产蛋率显著提高,且料蛋比显著降低。基础饲粮＋2．0％凹凸棒石粉处理组入舍母鸡产蛋率和入舍母鸡产蛋重均显著低于基础饲粮＋1．5％凹凸棒石粉处理组,而料蛋比显著高于基础饲粮＋1．5％凹凸棒石粉处理组。试验组的日耗料量、死淘率和破汤蛋率都有不同程度的降低,但差异均不显著。     

煤矸石层燃原理与工艺研究

介绍了研究开发的煤矸石层燃原理与工艺流程及其燃用特性,利用成型燃烧理论和助燃技术解决了煤矸石在层燃炉内难燃和烟尘污染严重等技术难题,为煤矸石废弃物的资源化洁净利用提供了一种切实可行的新技术。     

The boundary layer ecology — A new and developing branch of ecology

The paper concerns objects are the functional leaves ofPopulus davidiana three years old in natural environmental. We discuss mainly the structure, function, motional law of the ecological boundary and its ecological effects. The project was supported by Natural Science Fund of Heilongjiang Province     

放养条件下密度和补饲量对蛋鸡生产性能及蛋黄胆固醇含量的影响

选择45周龄体重接近的健康本地鸡441只,随机分为7组,在山西省太谷县生态养鸡场进行2(补饲量)×3(密度)两因子放养试验,研究林下种植苜蓿不同放养密度与补饲量对蛋鸡生产性能和蛋黄胆固醇含量的影响。补饲量设自由采食量50%、70%两个处理,密度为每667m2 100只、250只、400只3个处理,以笼养全程自由采食为对照,每组3个重复,每重复3个小区用于轮牧,小区面积为62 m2;预试期7 d,正试期70 d。结果表明:补饲量和放养密度互作对平均产蛋率影响极显著(P0.01),对蛋重和料蛋比影响不显著(P0.05)。笼养+自由采食组(CK)与补饲量70%、100只·667m-2组蛋重、平均产蛋率及料蛋比差异不显著(P0.05),但产蛋率显著高于其他各组(P0.05),蛋重显著高于补饲量50%、100只·667m-2组(P0.05),料蛋比显著低于补饲量50%组(P0.05)。补饲量和放养密度互作对蛋黄重、蛋黄胆固醇含量和全蛋胆固醇含量影响不显著(P0.05);放养密度对全蛋胆固醇含量影响极显著(P0.01)。笼养+自由采食组蛋黄重极显著高于补饲量50%、100只·667m-2组(P0.01),蛋黄胆固醇含量和全蛋胆固醇含量显著高于100只·667m-2组(P0.05)。补饲量70%下,100只·667m-2放养密度对牧草的破坏性小于其他放养密度。结合产蛋性能、蛋黄胆固醇含量以及草地保护,以70%补饲量+100只·667m-2组养殖模式较好,效果较佳。     

Prediction and measurement of residual stresses in injection molded parts

Residual stresses were predicted by a flow analysis in the mold cavity and residual stress distribution in the injection molded product was measured. Flow field was analyzed by the hybrid FEM/FDM method, using the Hele Shaw approximation. The Modified Cross model was used to determine the dependence of the viscosity on the temperature and the shear rate. The specific volume of the polymer melt which varies with the pressure and temperature fields was calculated by the Tait’s state equation. Flow analysis results such as pressure, temperature, and the location of the liquid-solid interface were used as the input of the stress analysis. In order to calculate more accurate gap-wise temperature field, a coordinate transformation technique was used. The residual stress distribution in the gap-wise direction was predicted in two cases, the free quenching and the constrained quenching, under the assumption that the shrinkage of the injection molded product occurs within the mold cavity and that the solid polymer is elastic. Effects of the initial flow rate, packing pressure, and mold temperature on the residual stress distribution was discussed. Experimental results were also obtained by the layer removal method for molded polypropylene.     

Development of an integrated Cropland and Soil Data Management system for cropping system applications

Most cropping system models and decision support tools are structured for site-specific (i.e. field- or point-based) simulation and analysis. As the need grows for analyses on crop production and management at local, county, state, national, and even global scales, cropping system models and decision support tools are increasingly structured to provide the capability for area-wide simulation and analysis at a range of spatial scales. A major challenge is the development of a data management system that can provide dynamic access to large volumes of geo-referenced data needed by such applications. The objective of this paper is to present a methodology to develop a Cropland and Soil Data Management system that is capable of automatic data consolidation and integration, and can provide dynamic access to the integrated data by cropping system applications. The Cropland Data Management component of the system is based on the Cropland Data Layer (CDL) products from the USDA National Agricultural Statistics Service and is implemented with seven program modules: Data Requester, Data Fetcher, Data Parser, Geodatabase Builder, Map Service Builder, Map Cache Generator, and Cropland Map Viewer. The Soil Data Management component is based on the Soil Survey Geographic (SSURGO) database from the USDA Natural Resources Conservation Service and is implemented with six program modules: Data Requester, Data Fetcher, Data Parser, Database Builder, Soil Map Generator, and Soil Map Viewer. The approaches and methodology presented in the paper can serve as a reference for those who are interested in developing integrated cropping system applications.     

Up-regulation of Endothelin-1 and Endothelin type A receptor genes expression in the heart of broiler chickens versus layer chickens

To compare Endothelin (ET) production and genes expression of ET-1 and ET_A receptor (ET_AR) between broiler and layer chickens during rearing, semi-quantitative RT-PCR and enzyme immunometric assay were performed in the heart ventricles and serum. There were gradual elevations of ET-1 and ET_AR mRNAs in the left ventricle of broiler and layer chicken groups that were mainly significant (P < 0.05) at 28, 35 and 42 days of age with compared to previous days whereas were not significant between two groups.These gradual elevations of ET-1 and ET_AR mRNAs were also observed in the right ventricle that were significant (P < 0.05) at 28, 35 and 42 days of age in broilers and 42 days of age in layers with compared to previous days. Increasing of these mRNAs in the right ventricle of broiler chickens were significantly (P < 0.05) more than layer chickens at 28, 35 and 42 days. Serum ET in broilers was significantly (P < 0.05) higher than layer chickens at 28 and 42 days of age. It is concluded that circulating ET and cardiac ET-1, ET_AR genes expression is higher in broiler chickens than in layer chickens particularly after 21 days of age. It is probably that these breed differences make broiler chickens to be more susceptible to Endothelin related-cardiomyopathies such as congestive heart failure and ascites.     

性别对蛋鸡饲料蛋白和能量代谢的影响

选用26周龄尼克粉公母鸡,结合套算法分别测定甘薯干、米糠、粟、糙米、葵花饼、啤酒糟、玉米蛋白粉和DDGS(玉米干酒糟)8种饲料原料的表观代谢能和蛋白代谢率。结果表明,用尼克粉鸡测得能量原料米糠、糙米表观代谢能公母间差异显著(P<0.05),母鸡测得的平均结果比公鸡分别高出0.61、1.03 MJ/kg,能量原料甘薯干、粟和葵花饼、酒糟、玉米蛋白粉、DDGS 4种蛋白原料的表观代谢能公母间差异不显著(P>0.05);米糠和葵花饼、酒糟、DDGS的粗蛋白代谢率公母间差异显著(P<0.05);玉米蛋白粉和甘薯干、粟、糙米的粗蛋白代谢率差异不显著(P>0.05),母鸡测得的平均结果均高于公鸡。说明性别对蛋鸡饲料蛋白和能量代谢有影响。     

四味健蚕增茧液中白头翁的薄层鉴别

采用薄层层析法(TLC)对四味健蚕增茧液中的白头翁药材进行鉴别,以硅胶G-CMCNa薄层板为固定相,氯仿-甲醇-水(70:30:10)作为展开剂,展开后喷10%H2SO4,105℃加热5～10 min显色,能较好地分离四味健蚕增茧酊中的各种成分,从而对处方中的白头翁进行质量监控。本方法简便、准确,重现性好,专属性强,可对复方中的白头翁药材进行定性和半定量检查。