无机离子的毛细管电泳分析及其在土壤上的应用

毛细管电泳用于溶液中无机离子的分析具有分离性能高、分离速度快、分析费用低、操作简单等优点,但精确性稍低。通过各种校准方法可部分地克服这一缺点。毛细管电泳极高的分离性能和极快的分离速度使土壤养分快速以至准实时分析成为可能,但其在土壤无机离子分析上的研究仍显不足,目前需要解决的问题之一是提高样品的前处理速度及对磷的提取能力。这些问题的解决将有利于提高土壤养分分析效率,促进毛细管电泳法在土壤养分分析方面的应用。     

土壤无机阴离子的毛细管电泳分析

采用以铬酸钠为背景电解质、十六烷基三甲基溴化铵为电渗流改性剂的间接紫外检测法电泳系统 ,研究了分离电压、缓冲液的酸碱性等毛细管电泳测定氯离子、硫酸根、硝酸根和磷酸根的基本条件 ,可在 5min内对以上 4个离子实现准确定量。测定了 5个采自全国不同地区的土壤样品水提取液中的无机阴离子。结果显示 ,毛细管电泳可对提取液中的氯离子、硫酸根和硝酸根实现较准确的定量 ,测定结果与离子色谱比较一致 ;对硝态氮的测定结果与KCl提取 流动分析结果相关性达到p <0 10水平 ,表明测定结果可在一定程度上反映土壤氮素养分状况。但土壤用水静止提取 2 4h ,提取液中的磷未达到毛细管电泳和离子色谱法的检测限 ,毛细管电泳的测定精确度不及离子色谱     

离子色谱法和毛细管电泳法测定土壤中氯离子、 硫酸根及其差异性

分别采用离子色谱法(IC)、毛细管电泳法(CE)两种仪器方法对不同pH土壤中Cl~–、SO_4~(2–)含量进行测定,并对其结果进行差异性分析。结果显示:参照标准物质的参考值(滴定法),IC与CE测定值的准确度、回收率均满足实验分析要求,但精密度差异较大,IC(RSD,3.61%)的稳定性优于CE(RSD,8.97%)。据差异性(F与t检验)分析,两种仪器方法测定酸性土壤中Cl~–、SO_4~(2–)含量存在显著性差异,而碱性、中性土壤的测定结果保持一致。对比4个被测样品基本性质发现,酸性土壤的pH与离子强度均低于其他样品,从而影响了石英毛细管的电渗流,最终改变了CE分离过程,这可能是Cl~–结果偏离的主要因素。同时,对于IC,酸性土壤较中性、碱性土壤更易由于离子交换效应产生次级保留(拖尾)。此外,采用碱性分离体系分离酸性样品易形成结晶,从而导致SO_4~(2–)含量的偏离。可见,两种方法各有优缺点。但是,IC较经典,而CE是一种新兴的仪器方法。测定像土壤这样基体较复杂的样品(特别是酸性土壤)中阴离子的仪器条件还需要进行更多摸索与优化,以促进这两种方法在土壤领域的推广与应用。     

种子蛋白质电泳在陆地型长绒棉种质鉴定中的应用

采用垂直平板聚丙烯酰胺凝胶法 ,进行单粒种子醇溶蛋白质电泳分析 ,参试材料有陆地型长绒新种质 9830 1系、4个海岛棉品种和 8个陆地棉品种。 9830 1和中棉所 1 2号、石远 32 1在试验中 ,同一品种 (系 )内的不同种子之间的蛋白谱带基本一致。对分别取样于山东省 7个不同地区试验点的 9830 1种子谱带进行比较 ,没有发现差异。胶板上陆地棉品种均具有 3条与海岛棉相区分的带 ,同样各海岛棉品种也共同具有 3条特征带。 9830 1显出 3条陆地棉特有带 ,证明其谱带主要倾向于陆地棉 ;同时也稳定地出现 1条海岛棉的特有带 ,表现出其属于海陆杂交种的遗传特性。 9830 1分离出一条独有带 (“1”带 ) ,凭借此带和另一条带 (“1 0”带 )可较容易地和其它陆地棉品种相区分     

毛细管电泳在茶叶有效成分分离检测中的应用

茶是世界上的三大饮料之一,喜欢饮茶的人有很多,尤其是东亚地区。饮茶的传统起源于中国,饮茶有利于提神,有利于消化。在我国的传统茶道中,对茶叶的评价大多是以人们的视觉、嗅觉、味觉和触觉的感受为依据,对茶叶的形状、香味及色泽来做出鉴定,但是这种方法存在着不确定的因素。随着高新技术的发展,毛细管电泳的技术在茶叶中得到了广泛的应用,详细分析毛细管电泳在茶叶有效成分分离检测中的应用。     

健康传播在畜牧兽医实践中的应用

在我国国民经济中,畜牧业占据着重要的地位,同时也是农村经济的重要支柱产业.畜牧兽医实践中,健康传播工作可以保证肉蛋食品安全,提升动物卫生保护工作水平,直接影响畜牧业的健康发展.但现阶段,健康传播在畜牧兽医实践中仍存在一些问题.基于此,针对健康传播在畜牧兽医实践中的问题进行深入分析,并提出相应解决措施,希望可以充分发挥出...     

加快我国畜牧兽医标准化工作的思考

标准化是产业化的基础。畜牧业的标准化可使畜牧生产达到最优化状态,提高畜牧产品质量,实现畜牧业产业化。目前我国畜牧兽医标准化工作还是处于比较落后的位置。因此实现我国畜牧兽医标准化具有很重要的意义。该文介绍了我国畜牧兽医标准化的内容,实施畜牧兽医标准化的意义,以及实施畜牧兽医标准化应注意的问题和采取的有效措施,提出了做好标准化工作必须要抓好的十个方面的工作,以及重点环节。并对推进畜牧兽医标准化的动力进行分析,包括行政推动力、市场拉动力、示范带动力和社会促动力。     

加快我国畜牧兽医标准化工作的思考

标准化是产业化的基础。畜牧业的标准化可使畜牧生产达到最优化状态,提高畜牧产品质量,实现畜牧业产业化。目前我国畜牧兽医标准化工作还是处于比较落后的位置。因此实现我国畜牧兽医标准化具有很重要的意义。该文介绍了我国畜牧兽医标准化的内容,实施畜牧兽医标准化的意义,以及实施畜牧兽医标准化应注意的问题和采取的有效措施,提出了做好标准化工作必须要抓好的十个方面的工作,以及重点环节。并对推进畜牧兽医标准化的动力进行分析,包括行政推动力、市场拉动力、示范带动力和社会促动力。     

毛细管色谱在农药残留分析中的应用及进展

农药的多残留分析系微量或超微量分析技术,不仅需要高灵敏度的检测器,更要求高分辨的分离系统。传统的填充色谱已经不能适应宽沸程混合物分离的要求。毛细管色谱的启用为解决这一难题开辟了新的途径。本文对固定液的选择、柱温的优化、进样系统的改进,以及双柱流、双检测器联用技术等方面的进展情况作了概述。     

Identification of long needle crystals and distribution of oxalate salts in Narcissus cv. ‘Garden Giant’

Long needle crystals abundantly present in the bulb scales and the shoot sap of Narcissus cv. ‘Garden Giant’ were identified as Ca-oxalate by ¹³C-nuclear magnetic resonance and capillary electrophoresis. The Ca-oxalate crystals were distributed in every part of the plant, including tunics, shoot, flowers, basalplate, and roots. A large proportion of water-soluble oxalate was present in the roots, but not in the scales and shoot. Oxalate accumulation occurred mainly in the young new scales originating from the basal part of shoot. Most of all the oxalate in the inner new scales and the outer old scales was in the form of Ca-oxalate. The fact that Ca and oxalate contents in old scales remained constant after planting to the flowering stage indicated that Ca and oxalate in bulb scales are not reserve nutrients supporting plant growth. Alternatively Ca-oxalate accumulated in scales appeared to be a stable end-product.     

Determination of leghemoglobin components and xylem sap composition by capillary electrophoresis in hypernodulation soybean mutants cultivated in the field

The hypernodulation soybean mutant lines (NOD1-3, NOD2-4, NOD3-7) and their parent Williams, and the mutant En6500 and its parent Enrei were cultivated in a sandy dune field in Niigata, and the nodules and root bleeding xylem sap were sampled at 50, 70, 90, and 120 d after planting (DAP). The nodule size distribution patterns and concentration of leghemoglobin components were determined. The number of nodules of the hypernodulation mutant lines was about two to three times higher than that of the parent lines irrespective of the sampling date. At 50 DAP the nodule size was relatively smaller in the hypernodulation mutant lines, and the total dry weight of the nodules was almost the same in the mutant lines and their parents. At 70 DAP and 90 DAP, the size distribution of the hypernodulation mutant nodules became .almost the same as that of the parent lines, and both the number and total dry weight of the nodules were higher than those of the parent lines. The concentration of four Lb components was separately measured by capillary electrophoresis. The concentration of the Lb components in the hypernodulation mutant lines tended to be lower than in the parents, but the component ratios were not different between the hypernodulation mutants and their parents. Under field conditions, plant growth and nodulation characteristics were more similar between mutants and parents than in the hydroponic culture reported previously, although the mutants did exhibit hypernodulation traits. These findings suggest that the decrease in the Lb concentration and the different Lb components ratios in the mutants may be caused by secondary effects of excess nodulation, such as photosynthate deficiency, rather than by a genetic defect in mutation. The concentration of major nitrogenous compounds (allantoic acid, allantoin, asparagine, aspartic acid, and nitrate) in the xylem sap was also measured by capillary electrophoresis. The concentration of ureides and nitrate in xylem sap decreased with the plant age, but the asparagine concentration increased during the same period. The concentrations of ureides and asparagine were higher, and the nitrate concentration was lower in the mutant lines than in their parents, possibly due to the higher dependence on N₂ fixation than N0₃ ^- utilization. In the xylem sap, nitrate was the major inorganic anion followed by phosphate, sulfate, and chloride, and potassium was the major cation followed by calcium or magnesium and sodium.     

采用碱提酸沉与淀粉酶解复合法制备小麦胚芽蛋白的试验研究

为了改善小麦胚芽蛋白质的提取效果,建立了“碱提+α-淀粉酶水解+酸沉淀”分离小麦胚芽蛋白的新方法。与传统的碱溶酸沉淀法相比,该方法明显地提高了小麦胚芽蛋白的纯度和得率,其数值分别达到94.5%和81.36%。用高效毛细管电泳定性测定了小麦胚芽蛋白的纯度,结果进一步证明该方法得到的小麦胚芽蛋白纯度较高。用SDS-PAGE电泳测定了小麦胚芽蛋白的分子量,结果表明小麦胚芽蛋白的分子量主要由35kDa和55kDa组成。     

用于水肥系统的养分离子快检装置研制与试验

针对农业生产中难以现场、精准、快速获取水肥系统中养分离子含量的问题,该研究设计了一套针对水肥溶液与浇灌尾水中K+、NO3-、NH4+、PO43-4种养分离子的快检装置。该装置结合了毛细管电泳（Capillary Electrophoresis,CE）技术和电容耦合非接触电导检测（Capacitively Coupled Contactless Conductivity Detection,C4D）技术,首先使用CE的方式实现养分离子快速分离,再利用C4D原理进行精准测量,在10 min内即可完成单个指标检测。装置由高压系统、C4D检测器、毛细管通道、数据采集卡和上位机组成,采用触摸屏控制,操作简便。为了提升检测效果,在C4D检测器的电路设计上引入了锁相放大技术,测试了其在不同幅值Vp和工作频率f下的输出特性曲线,确定了最优参数为f =490 kHz,Vp=75 V（阳离子）,Vp=60 V（阴离子）。使用装置对K+、NO3-、NH4+、PO43-这4种离子的标准溶液进行检测分析,检测限均可达到1 μg/L。最后,为了验证装置的有效性和现场适应能力,在安装了水肥系统的草莓种植温室中对水肥溶液与浇灌尾水样品进行了现场测试,仅需少量样品和简单操作即可快速得出结果,4种养分离子的检测结果相对标准偏差均小于7%,表明该研究提出的装置可以有效地实现配比后的水肥溶液与浇灌尾水的现场快速检测。研究结果为水肥系统的养分离子检测提供了一种可靠的方法与装置,可为设施农业的高效肥料管理提供数据支持。     

多因素影响下土壤上升毛管水运动特性HYDRUS模拟及验证

基于饱和—非饱和土壤水分运动理论,通过HYDRUS-1D软件对多因素作用下的土壤上升毛管水运动进行模拟,研究土壤容重、黏粒含量、初始含水率、地下水埋深和时间5个因素对上升毛管水运动特性的影响。分别建立上升毛管水补给量和毛管水上升高度与各影响因素之间经验模型,其均方根误差均为0.003 cm,相关系数均大于0.99,决定系数均大于0.98(P0.01),计算值与实测值相对误差均小于11.25%。各影响因素对上升毛管水补给量的影响程度由大到小依次为时间、土壤容重、初始含水率、黏粒含量、地下水埋深,对毛管水上升高度的影响程度由大到小依次为时间、初始含水率、黏粒含量、土壤容重、地下水埋深。采用截距为0的线性函数对毛管水上升高度与上升毛管水补给量之间的关系曲线进行拟合,其决定系数均在0.96以上,表明其两者之间呈显著线性关系。该研究成果可为制定灌溉和排水以及盐碱地改良等措施提供理论依据。     

茶树种植对中国东部黄棕壤酸化的影响

Soil acidification is an important process in land degradation around the world as well as in China. Acidification of Alfisols was investigated in the tea gardens with various years of tea cultivation in the eastern China. Cultivation of tea plants caused soil acidification and soil acidity increased with the increase of tea cultivation period. Soil pH of composite samples from cultivated layers decreased by 1.37, 1.62 and 1.85, respectively, after 13, 34 and 54 years of tea plantation, as compared to the surface soil obtained from the unused land. Soil acidification rates at early stages of tea cultivation were found to be higher than those at the later stages. The acidification rate for the period of 0-13 years was as high as 4.40 kmol H⁺ ha^-1 year^-1 for the cultivated layer samples. Soil acidification induced the decrease of soil exchangeable base cations and base cation saturation and thus increased the soil exchangeable acidity. Soil acidification also caused the decrease of soil cation exchange capacity, especially for the 54-year-old tea garden. Soil acidification induced by tea plantation also led to the increase of soil exchangeable Al and soluble Al, which was responsible for the Al toxicity to plants.     

镉胁迫下的实验室放线菌种群结构变化的DGGE分析

The actinomycete populations and functions in cadmium (Cd) contaminated soil were investigated by the cultivationindependent molecular methods. The genomic DNA was extracted and purified from soil adulterated with various concentrations of Cd in the laboratory. The partial 16S rDNA genes were amplified by polymerase chain reaction (PCR) using specific primers bound to evolutionarily conserved regions within these actinomycete genes. The diversity in PCRamplified products, as measured by denaturing gradient gel electrophoresis (EGGE), was used as a genetic fingerprint of the population. Principle component analysis and Shannon-Weaver diversity index (H) analyses were used to analyze the DGGE results. Results showed that the two principal components accounted for only a low level of the total variance. The value H in contaminated soil was lower than that in the control at later stages of cultivation, whereas at earlier stages it was higher. Among the six sampling time points, the first, fifth and sixth weeks had the highest values of H. Significantly negative correlations between bioavailable Cd concentration and H values existed in the samples from weeks 2 (R = 0.929, P < 0.05) and 4 (R =0.909, P < 0.05). These results may shed light on the effect of Cd on the soil environment and the chemical behavior and toxicity of Cd to actinomycetes.     

均质土壤毛管水上升特性室内试验研究

针对西北地区因过量灌溉而引起的土壤盐渍化问题,通过室内模拟土柱试验,对地下水埋深较浅(仅为地面以下70 cm)的均质土上升毛管水运动特性进行了研究,分析了毛管水上升高度、地下水毛管补给量与时间之间的关系,以及毛管水上升高度与地下水补给量之间的关系,探明了地下水毛管上升的运动机理。结果表明,均质土壤毛管水上升高度和地下水补给量与时间之间均为幂函数关系,毛管水上升高度与地下水毛管补给量之间呈明显的线性关系。     

两种剂量重离子辐照绵羊精子差异蛋白质组学研究

为检测和分析0.5和3.0Gy 2种剂量重离子辐照绵羊精子差异表达的蛋白质,用二维凝胶电泳分离精子蛋白,凝胶用硝酸银染色,PDQuest8.0检测分析差异表达蛋白斑点并经高效液相色谱串联离子阱质谱鉴定,结果显示:2种剂量凝胶图谱分析后得到8个共同差异蛋白斑点,鉴定为3种表达上调的蛋白质(谷氧还蛋白1、转录因子AP-2α...