蛇腹鳞表面的超微结构及减阻机理

用原子力显微镜观测了竹叶青蛇、短尾蝮蛇和赤链华游蛇腹鳞表面的超微结构,分析了腹鳞表面的减阻机理。结果表明:3种蛇腹鳞表面的超微结构均为微凸体、微孔和凹坑周期排列的规律结构;蛇的栖息环境不同,超微结构的排间距、微凸体长度以及微孔的直径、数量不同。从陆栖到水栖,微凸体长度逐渐减小,微孔数量逐渐增加。微凸体减少了腹鳞和地面间的实际接触面积,从而减小了滑动时的粘着力;腹鳞表面的疏水性,减少了接触面间水的粘附力。     

农民转移是柳州市全面建设小康社会的关键

增加农民收入是当前农业和农村工作的中心任务,是全面建设小康社会的必然要求.如果再单纯就农村抓农业或就农业抓农业,要大幅度增加农民收入是不可能的.因此要以非农的观念来思考"三农"问题,有则是以经营工业的理念来经营农业,以经营城市的理念来经营农村,要求我们在明晰资源基础上,定人定岗地组织生产.而在全国、全自治区,全市劳动力富余50%的今天,研究和解决转移农民已成为实现全面小康社会不可回避的突出问题.     

部分栽培葱属植物叶绿体基因组的RAPD分析

  提取我国栽培的几种主要葱属植物的叶绿体DNA , 利用RAPD 技术进行遗传关系分析。从56 个10 bp 随机引物中筛选出18 个多态性引物进行扩增分析, 14 个材料共扩增出270 条带, 其中246 条具多态性。UPGMA 聚类将供试葱属品种分成4 个组。葱属在进化上存在两个方向, 分别形成了管状叶和扁平叶两种类型。     

几种小红栲变性淀粉的结构特性

目前世界上变性淀粉的年产量已经达到500万t左右,如美国为200万t以上,欧洲为90万t,日本在30万t以上;而我国在2000年变性淀粉的产量为35万t,仅为世界产量的7%,根本无法满足国内109万t以上的市场需求而每年都要从国外进口     

Effect of high temperature heat treatment on pH value of Masson Pine wood

Heat-treated wood has good dimensional stability,corrosion resistance and visual quality,but it is prone to mold,which limits its application.Based on the pH value of heat-treated wood,this study examines the factors affecting the pathogenesis causing heat-treated wood mold.Normally,the pH value of the heat-treated wood is between 4.38 and 5.10,which is suitable for the growth of mold.However,the pH of the heat-treated copper-containing material is between 6.63 and 7.12,which deviates the treated wood from the comfortable growth conditions for the mold,thereby reducing the occurrence of mold.     

链球菌引起猪关节炎的治疗

2008年4月,我市某农户饲养的12头小猪因天气乍寒乍暖,饲养管理不善,卫生条件不良等原因出现了关节炎症状,曾用青霉素治疗,但效果不佳,病情越来越严重,有的后肢瘫痪,行走困难。     

猪金黄色葡萄球菌病的诊疗

2008年11月23日,我镇一生猪养殖场仔猪保育舍内的7只断奶仔猪在28日龄发生金黄色葡萄球菌感染,2只已死亡,另外5只经治疗后痊愈。现将诊疗过程报告如下。     

黑龙江省中熟大豆品种主要农艺性状演变趋势分析

黑龙江省近20年来中熟大豆品种遗传改进的明显趋势是株高、有效节数、一二粒荚数、三四粒荚数、单株荚数、单株粒数、每荚粒数和单株粒重增加,底荚高度略有增加。分枝数、蛋白质含量呈现先增后减的趋势．脂肪含量呈现先减后增的趋势,百粒重变化不大。株高、有效节数、三四粒荚数、单株荚数、单株粒数、百粒重与单株粒重呈显著或极显著的正相关。各性状对单株粒重的贡献大小依次为单株粒数、单株荚数、三四粒荚数、株高、有效节数、百粒重。提高单株粒数、单株荚数、三四粒荚数．兼顾株高、有效节数、百粒重是该区大豆育种的主攻方向。     

Leaf photosynthesis is enhanced in normal oil maize pollinated by high oil maize hybrids

The grain yield of normal oil maize (Zea mays L.) might increase when pollinated by high oil maize (HOM) hybrids because of heterosis. To testify that the grain yield increase might be a result of improved photosynthetic rate and related traits, the normal oil maize (NOM) hybrid, Nongda108, was cross-pollinated by three HOM hybrids, HOM202, HOM115 and HOM4515 (for short as ND108pHOM202, ND108pHOM115 and ND108pHOM4515). We found that the ND108pHOM202 and ND108pHOM115 exhibited higher net photosynthetic rate (P_n), accompanied by larger stomatal conductance (g_s) and transpiration rate (E). Moreover, delayed leaf senescence was observed in their leaves, including larger leaf area index (LAI) and higher Chl content and Chl a/b ratio. Apart from higher phosphoenolpyruvate carboxylase (PEPCase) activity, the soluble proteins were also higher in the two cross-pollinations. The higher leaf photosynthesis could explain the grain increase in ND108pHOM202 and ND108pHOM115. However, ND108pHOM4515 exhibited a decreased photosynthetic characteristic and yield performance. Significantly positive relation between grain yield and biomass (r² = 0.96, P < 0.05), P_n and biomass (r² = 0.74, P < 0.05) also suggested that the yield increase in the two cross-pollination treatments was generally owing to the higher photosynthetic rate and related photosynthetic traits.     

覆盖措施对咸水结冰灌溉后土壤水盐动态和棉花生产的影响

对咸水结冰灌溉融冰后不同防止返盐措施处理的土壤水盐动态以及棉花的出苗、生长特征和产量进行了研究。结果表明,不同的覆盖措施对抑制土壤表层水分蒸发的效果有显著差异,3月和4月份表层土壤含水量影响5月份的含盐量,而5月份表层土壤的含盐量直接决定棉花出苗率。地膜覆盖和保留前茬旧膜的处理保墒抑盐效果最好,棉花出苗率和产量也最高;秸秆覆盖也有一定的抑盐效果;而翻耕和中耕对土壤保墒抑盐的作用较差;液态膜处理的抑盐效果最差,棉花的出苗率和产量最低。可见保留前茬旧膜是简便有效的保墒抑盐途径。