卓越饲料营销的7个习惯

<正>营销是条不归路,只能不断前进,没有终点,它始终挑战着人们的各种极限。特别是饲料营销,远离都市的繁华,终日与农村、农民和猪、鸡、鸭、鱼为伍。但只要我们喜欢,7个习惯就能帮助     

强普生Ⅲ号对H5N1亚型禽流感病毒的杀灭试验

强普生Ⅲ号是以多种植物为原料,采用科学方法提练精制而成的中草药,其富含鞣质、毛莨黄素、生物碱、酚类、黄酮甙、靛甙、蒽醌甙等物质,能增强动物机体的免疫功能.提高动物机体抗应激的能力,有很好的抗病毒作用。与常用的消毒药物相比较,强普生Ⅲ号具有不含任何化学物质,无毒副作用、不易产生耐药性、无残留的特点。本试验结果表明:强普生Ⅲ号与禽流感病毒作用10分钟后,原液、1:5、1:10、1:20、1:40、1:80的受试液对病毒的杀灭率均为100%,有完全的杀病毒作用, 是一种理想的绿色环保型消毒剂。     

浅析无线路由器信号覆盖范围的拓展

由干无线网络设备的有效信号覆盖范围限制,在实际应用中经常出现无信号或信号不稳定现象,本文根据无线局域网中核心设备无线路由器的特点,总结了信号覆盖范围拓展的常用方法.并重点讨论了采用WDS技术连接多个路由器来拓展信号覆盖范围的方法,并给出了具体的配置步骤.     

花生联合收获机械试验选型方法研究

从花生联合收获机的试验条件、适应性、作业质量、经济效果等方面,提出挖拔组合式花生联合收获机试验选型主要评价指标、评价原则和方法。     

恢复承德玉米制种基地的可行性分析

承德具有自然隔离条件好、气候类型丰富等独特的自然条件,曾是我国高粱和玉米“两杂”作物种子的主要生产基地之一.但由于受多种因素的影响,到20世纪中后期,种子生产基地面积逐步减少.分析了承德作为玉米制种基地的有利条件以及制约制种基地建设的主要因素,提出了适宜的基地建设规模.认为恢复承德玉米制种基地对于推动种子生产基地建设和管理、确保农业生产用种安全和种子业持续健康发展是十分必要和可行的.     

关于生物质气化集中供气规范化问题的探讨

近年来,我国生物质气化技术发展迅速,但在技术推广中出现了很多问题,其主要原因是没有规范化生产和管理。本文探讨了生物质气化集中供气规范化的有关问题。     

直线发动机低转速空燃比及燃烧特性

基于自主研发的直线发动机台架,进行直线发动机起动试验,采用速度-密度法,分析得到直线发动机在低转速时的循环进气量计算公式,并试验标定了直线发动机电控喷油器的流量特性。基于循环进气量计算公式与试验标定的直线发动机电控喷油器的流量特性,利用直线发动机起动试验测得的进气压力及缸压信号,计算得到当直线发动机起动循环喷油脉宽为5.4ms、点火时刻为上止点前1.0mm、发动机转速为575r/min时的空燃比为7.92,燃烧累积放热量为66J。研究表明,当活塞位于上止点前26mm时,循环进气量与此时进气道的瞬时进气压力线性度为0.03,线性特性最好。研究结果可为后续直线发动机空燃比计算及燃烧特性分析提供参考。     

Roles of biotic and abiotic variables in determining spatial variation of soil respiration in secondary oak and planted pine forests

Monoculture pine plantation (PP) was widely established after clear-cutting of natural forests last century in China. However, its effects on soil CO₂ efflux (R_S) temporally and spatially are still poorly understood. Biotic and abiotic factors that control spatio-temporal variation of R_S were assessed in a naturally regenerated oak forest (OF) and a nearby PP in a warm temperate area of China. We hypothesized that spatial variation of R_S in PP is lower than that in OF and is less influenced by biotic factors due to its homogeneous stand structure compared to the regenerated OF. R_S measurement campaigns were conducted in two 40 m × 60 m plots in OF and PP from Oct. 2008 to Oct. 2009. Soil temperature at 5 cm depth (T₅) exerted considerable influence on the temporal variation in R_S. However, the spatial variation of R_S was not affected by T₅ in either PP or OF. The observed spatial pattern of R_S remained comparatively consistent throughout the measurement campaigns for both forests. Soil chemical and physical parameters such as soil organic carbon (SOC), light fraction organic carbon (LFOC), total nitrogen (TN), bulk density (BD), total porosity (TP), water-filled pore space (WFPS), and water-holding capacity (WHC) had significant impact on the spatial variation of R_S for both OF and PP. We found that biotic factors such as fine root biomass (FR) and stand structure parameters including basal area (BA), maximum diameter at breast height (max. DBH), and mean DBH within 4–5 m of the measurement points had significant influence on the spatial variation of R_S in OF, while no similar significant correlation was found in PP. A stepwise multi-linear regression showed that water-holding capacity (WHC), max. DBH within 4 m of the measurement points (max. DBH₄), and total porosity (TP) contributed 68.7% to the spatial variation of R_S in OF, while light fraction organic carbon (LFOC) and bulk density (BD) accounted for 46.9% of the spatial variation of R_S in PP. These differentiated the importance of biotic and abiotic factors in controlling the spatial variation of R_S between the naturally regenerated OF and the artificially regenerated monoculture PP. Therefore, compared to OF, relatively lower coefficients of spatial variation for R_S were observed in PP across the year, which was partly attributed to its simple stand structure of PP. Our findings are valuable for accurately estimating regional carbon fluxes by considering the spatio-temporal variation of R_S in artificially and naturally regenerated forests.     

食品中铅的安全性分析

铅是一种重金属,由于目前金属铅的广泛应用,使得食品受铅的污染十分严重。全面综述了铅的毒性及其危害,指出减少铅污染的措施。