油菜覆膜打孔穴播机打孔装置设计与试验

为实现油菜等小粒径作物覆膜种植中膜上均匀打孔的功能,针对传统膜上成穴装置结构庞大复杂、工作时易黏土挑种及撕挑地膜等问题,设计了一种法兰式滚轮与螺纹式圆锥型锥钉组合式结构的打孔装置,确定了其主要结构参数范围;构建了打孔装置运动学模型,分析了打孔锥钉关键点的运动轨迹,确定了膜上打孔过程,并基于轨迹方程分析了膜孔尺寸参数;运用ADAMS运动学仿真,采用四因素三水平正交试验方法,以打孔锥钉顶角、打孔锥钉直径、打孔滚轮半径、机组前进速度为试验因素,以膜孔长度、膜孔间距偏差为试验考核指标,进行了打孔装置结构和运动参数的仿真试验。仿真结果表明:影响膜孔长度的因素主次顺序为打孔滚轮半径、打孔锥钉顶角、打孔锥钉直径、机组前进速度;影响膜孔间距偏差的因素主次顺序为打孔滚轮半径、机组前进速度、打孔锥钉顶角、打孔锥钉直径;基于参数优化,获得较优参数组合为:打孔锥钉顶角53°、打孔锥钉直径16 mm、打孔滚轮半径65 mm、机组前进速度4 km/h。以打孔装置较优结构参数组合进行了田间验证试验,结果表明:打孔装置所打膜孔形状较规则,普遍呈类圆形状,膜孔长度均在18 mm以上,膜孔间距较为均匀,与仿真结果基本一致;各行膜孔长度一致性变异系数为4.98%,各行膜孔间距均匀性变异系数为3.44%。结果表明试验参数组合选取合理,打孔装置符合设计要求。     

卵磷脂桶混助剂的特性及其在防治稻飞虱中对氟啶虫胺腈的协同增效作用

为明确新型卵磷脂类桶混助剂“融透”的特性，采用透射电镜和激光粒度分析仪表征了其物理性质，并通过室内生物测定和田间药效试验测定了其在防治稻飞虱中对氟啶虫胺腈的协同增效作用。结果表明，“融透”中含有圆形脂质体，Z平均粒径为129.5 nm。室内生物测定结果表明，“融透”可使氟啶虫胺腈对褐飞虱的毒力增加1.67倍。田间药效试验表明，“融透”可使氟啶虫胺腈对稻飞虱的防效提高9.04%~41.77%；当氟啶虫胺腈减量40%时，添加“融透”的处理对稻飞虱的防效与未添加“融透”的常量组相当。研究结果表明，卵磷脂桶混助剂“融透”可以通过形成脂质体提高药剂的利用率，从而达到增效的作用。     

我国喀斯特断陷盆地石漠化区植物群落构建机制研究

喀斯特断陷盆地是我国石漠化综合治理8大喀斯特类型中治理成效最低、治理难度最大的区域，面临石漠化严重、干旱频发、植被恢复难等突出问题。文中针对水分是影响喀斯特断陷盆地石漠化治理与植被恢复成效最关键的限制因素，综合分析了国内外水分梯度差异与植物群落构建机制研究动态与发展趋势；提出利用日趋成熟的水分脆弱性评价方法，通过建立基于耦合暴露度、敏感性及适应性的水资源脆弱性评价指标体系，以满足遥感影像分辨率和植物群落调查样地大小的评价单元进行水分脆弱性评估；在建立物种库—功能性状—生境特征数据库的基础上，提出基于功能性状差异进行喀斯特断陷盆地植物群落机制构建的研究方案。提出的研究方案有望解决喀斯特断陷盆地石漠化区水分梯度特征与分布格局、自然植物群落组配规律及其生境特征、水分梯度与生境要素对植物群落特征及功能性状组成的影响规律等关键科学问题，可为不同脆弱生态区植被恢复群落构建机制研究提供重要参考和借鉴。     

液电混合直线驱动系统位置控制特性研究

提出了一种采用电-机械直线执行器和液压缸的液电混合直线驱动系统。为消除电-机械直线执行器和液压缸之间的耦合影响,液压泵和比例阀协同控制液压缸输出力和运行方向,满足系统负载力需求,电-机械直线执行器用于运动控制,并补偿液压缸输出力波动和外部干扰力。为实现上述目标,设计了基于扩张状态观测器的电-机械直线执行器自适应滑模控制方法,以估计的负载力调节泵压力和比例阀开度,对液压缸输出力进行调控。比例阀在系统运行中主要用于控制液压缸运动方向,阀开度较大,可显著降低节流损失。通过仿真和试验分析了系统的运行特性和能效特性。结果表明,该系统具有良好的位置控制特性,能量效率高,较传统阀控系统能耗减少51%。     

Inhibitory Effects of AURKB Gene on Apoptosis and Cancer Cell Growth in HCT 116 Cells

[Objectives]To explore the inhibitory effect of AURKB gene in apoptosis and cancer cell growth in HCT 116 cells.[Methods]The in vitro cytology studies were carr...     

川东南浅丘区夏玉米生产现状与发展建议

四川是油菜第一大省,川东南浅丘区是四川油菜主产区,接茬油菜的夏玉米生产对于粮食安全战略具有重要作用。通过分析川东南浅丘区夏玉米生产现状,对该地区今后油菜—玉米轮作模式进行夏玉米生产提出一些建议。     

黑龙江省农产品深加工产业发展现状与对策

黑龙江省的农产品加工体系已经初步形成，但农业发展主要依赖于“原”字号产品。阐述了黑龙省农产品深加工产业建设存在的问题，通过分析制约农产品深加工产业发展的主要原因，从优化种植结构、整合现有资源、拓宽农产品销路以及提高农产品附加值4个方面提出解决对策。旨在做强食品加工业，上调农产品利润空间，通过“大龙头、大链条、大产业、大品牌的高效农业全产业链”促进粗放农产品向高附加值产品的转变，努力实现从产粮大省到农业强省的新跨越。      

Effect of dietary calcium or phosphorus deficiency on bone development and related calcium or phosphorus metabolic utilization parameters of broilers from 22 to 42 days of age

This experiment was conducted to investigate the effect of dietary calcium (Ca) or phosphorus (P) deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age based on our previous study, which indicated that dietary Ca or P deficiency impaired the bone development by regulating related Ca or P metabolic utilization parameters of broilers from 1 to 21 days of age. A total of 504 one-day-old Arbor Acres male broilers were randomly assigned to 1 of 4 treatments with 7 replicates in a completely randomized design, and fed the normal control and Ca- or P-deficient diets from 1 to 21 days of age. At 22 days of age, the broilers were further fed the normal control diet (0.90% Ca+0.35% non-phytate P (NPP)), the P-deficient diet (0.90% Ca+0.18% NPP), the Ca-deficient diet (0.30% Ca+0.35% NPP) or the Ca and P-deficient diet (0.30% Ca+0.18% NPP), respectively. The results showed that dietary Ca or P deficiency decreased (P<0.05) tibia bone mineral density (BMD), bone breaking strength (BBS), ash content, tibia ash Ca content and serum P content on days 28 and 42, but increased (P<0.05) tibia alkaline phosphatase (ALP) activity of broilers on day 42 compared with the control group. Furthermore, the broilers fed the P-deficient diet had the lowest (P<0.05) tibia BMD, BBS, ash content, serum P content and the highest (P<0.05) serum Ca content on day 28 compared with those fed the Ca-deficient or Ca and P-deficient diets. The results from the present study indicated that the bone development and related Ca or P metabolic utilization parameters of broilers were the most sensitive to dietary P deficiency, followed by dietary Ca deficiency or Ca and P-deficiency; dietary Ca or P deficiency impaired the bone development possibly by regulating serum Ca and P contents as well as tibia Ca content and ALP activity of broilers from 22 to 42 days of age.     

Protective efficacy of an H5/H7 trivalent inactivated vaccine produced from Re-11, Re-12, and H7-Re2 strains against challenge with different H5 and H7 viruses in chickens

We developed an H5/H7 trivalent inactivated vaccine by using Re-11, Re-12, and H7-Re2 vaccine seed viruses, which were generated by reverse genetics and derived their HA genes from A/duck/Guizhou/S4184/2017(H5 N6)(DK/GZ/S4184/17)(a clade 2.3.4.4 d virus), A/chicken/Liaoning/SD007/2017(H5 N1)(CK/LN/SD007/17)(a clade 2.3.2.1 d virus), and A/chicken/Guangxi/SD098/2017(H7 N9)(CK/GX/SD098/17), respectively. The protective efficacy of this novel vaccine and that of the recently used H5/H7 bivalent inactivated vaccine against different H5 and H7 N9 viruses was evaluated in chickens. We found that the H5/H7 bivalent vaccine provided solid protection against the H7 N9 virus CK/GX/SD098/17, but only 50–60% protection against different H5 viruses. In contrast, the novel H5/H7 trivalent vaccine provided complete protection against the H5 and H7 viruses tested. Our study underscores the importance of timely updating of vaccines for avian influenza control.     

香蕉与B基因组相关的SCAR标记研究

香蕉(Musa L.)是由2个二倍体野生种Musa acuminata Colla(AA基因型)和Musa balbisiana Colla(BB基因型)种内或种间杂交进化而来,其B基因组中带有重要的优良基因。利用与香蕉B基因组相关的gypsy-IRAP分子标记,成功开发了一对SCAR引物,适用于鉴定尖叶蕉(AAw)、长梗蕉(BB)、香牙蕉(AAA)、贡蕉(AAcv)、大蕉、粉蕉(ABB)、粉大蕉(ABB)、龙牙蕉(AAB)以及四倍体香蕉(AAAB)等是否含有B基因组。