两种测定风化煤与土壤腐殖酸含量方法的比较

选择GB11957-2001中的容量法和土壤腐殖质组成测定法,比较二者对风化煤、耕层土壤(石灰性褐土)、矿区土壤(栗钙土)腐殖酸含量的测定结果,及其实验过程、样品用量的不同,并对土壤腐殖质组成测定法中重铬酸钾溶液浓度进行比较选择。结果表明,GB11957-2001中的容量法对风化煤、耕层土壤(石灰性褐土)腐殖酸含量测定结果约为土壤腐殖质组成测定法的4倍,但对于腐殖酸含量较低的矿区土壤(栗钙土),两种方法测定结果相同。相对而言,GB11957-2001中的容量法在实验过程中更易达到实验要求,具有易操作性。通过实验,提出了风化煤、土壤样品分别在两种实验方法中的合理用量,和土壤腐殖质组成测定法中重铬酸钾的合理浓度为0.4000mol/L。     

浅谈会计电算化与传统会计

会计作为一个提供财务信息为主的信息系统，在企事业经营管理中起着重要作用。电算化会计不仅是使用计算机替代手工进行会计处理，分析、预测、控制、决策；减轻会计核算的劳动强度，而且更利于会计信息的产生与应用。     

燃料油与燃煤综合应用效益对比分析

对比了燃煤与燃油的燃烧值与其当前的市场价格,以及运煤车辆的耗油和大修的相关标准参数。从燃油与燃煤产生的能耗与需要投入的风险、运输、折旧及培训等费用成本两方面进行了综合分析。对此分析结果表明,当运煤距离超过300km时,燃油的综合效益高于燃煤,并有利于环保,避免资源重复利用,有效提高了资源的利用效益。     

草地早熟禾品种间幼苗耐盐性差异的研究

本文采用室内盐胁迫水培幼苗的方法，对五个草地早熟禾品种的耐盐性差异进行比较研究。结果表明：大青山，肯特基二个品种幼苗细胞膜忍受盐浓度的极限范围在０．８－１．２％之间，自由神，菲尔金和帕克三个品种在１．２－１．６％之间。品种的耐盐性与膜透性的增加和脯氨酸的积累量呈负相关，与植株生长状况呈正相关。     

中立型时滞微分方程解的振动性质

In this paper, we study the oscillation of solutions of neutral delay differential equations. Our results extend and improve some theorems in papers[1,3,10]. We also obtain sufficient conditions for Eq.(1) to have a nonoscillatory solution.     

马铃薯S病毒的分子鉴定与检测

An isolate of PVS, HZ00P1, was obtained from nature infected Solanum tuberosum from Hang-zhou, Zhejiang province. It was primarily identified by DAS-ELISA and host reaction tests. 3' end partial sequence of the virus isolate was cloned. Nucleic acid sequence of the cp gene and deduced cp amino acid se-quence alignments were compared with 16 other isolates registered in GenBank. The results showed that the 17 PVS isolates were divided into two groups. Among them, two Andean isolates were classified to group Ⅱ, HZ00P1 and the other 14 isolates were assigned to group Ⅰ. Compared with other PVS isolates in group Ⅰ, PVS HZ00P1 had 93.1%-98.1% and 95.9%-99.3% homologies of nucleotide sequence and deduced amino acid sequence respectively, whereas its similarities to the group Ⅱwere 81.4%-81.7% and 93.5%-93.9%. A survey of PVS occurrence in Zhejiang province was achieved by RNA spot hybridization (RSH). Among the 30 samples collected from different areas of the province, 26.7% were found to have the infection of PVS. It is concluded that PVS has become a common virus in Zhejiang province.     

A comparison of the effects of parenteral and oral administration of supplementary vitamin E on plasma vitamin E concentrations in dairy cows at different stages of lactation

As a result of research conducted in the US, recommendations for dry cow vitamin E intakes have increased seven fold there, however there has been no change to recommendations in the UK. As part of a larger study comparing the impact of existing UK and new US recommended vitamin E intakes on the health and fertility of commercial dairy cows in the UK, a study was set up to investigate the effect of route of supplementation and stage of lactation, over a 21 day period, on the response to mega-supplementation of cattle receiving supposedly adequate vitamin E. The study assessed the response of dry, peak lactation and mid lactation cows to in-feed or parenteral vitamin E supplementation (7 animals per treatment/lactation stage group) by measuring plasma and milk vitamin E concentrations, blood glutathione peroxidase (GSH-Px) activity and milk yields over a 21 day period. Plasma vitamin E concentrations were significantly influenced by a time, stage and treatment interaction (P = 0.046). Both dry and lactating animals had significantly higher plasma vitamin E concentrations at some time points in the parenteral supplemented cows compared to the in-feed supplementated animals (P ≤ 0.011 and P < 0.01, respectively). Milk vitamin E concentrations did not significantly differ between lactation stages but treatment had a significant effect on concentrations (P < 0.008) when lactation stage was removed from the model. There was no significant difference in milk yield between treatment groups. A significant relationship between plasma and milk vitamin E concentrations was only found in the parenterally supplemented cows (r = 0.435, P < 0.001). In cattle with intakes greater than the ARC recommendations, measurement of plasma vitamin E concentration may be of limited value in determining whether there has been a response to supplementation. The relationship between plasma and milk vitamin E concentrations is too poor for milk vitamin E concentrations to be used as a proxy for plasma vitamin E.     

鸡白痢沙门菌基因组差异片段的筛选与分析

采用抑制性消减杂交技术（SSH）对鸡白痢沙门菌C79-13株与鸡伤寒沙门菌Sg9株进行了基因组差异片段分析.结果,从C79-13株中共检出13个特异性差异片段.经同源分析,这些序列可分为3类：噬菌体相关序列、质粒相关序列和已知功能序列.这些差异片段包含一些重要的沙门菌毒力相关基因,如编码大肠杆菌素、IpaJ蛋白、尾突蛋白、切除酶的基因.结果表明,鸡白痢沙门菌C79-13株与鸡伤寒沙门茵Sg9株基因组问存在较多差异基因,这些差异片段为确定鸡白痢沙门菌特异性遗传标志,建立分子鉴别新体系提供了基础.     

驯鹿狂蝇(Cephenemyia trompe)线粒体COI基因序列研究

利用分子生物学技术对驯鹿狂蝇蛆及其成蝇（Ccphenemyia trompe）的线粒体COI基因种属特异性序列进行了研究。DNA核苷酸测序结果证实：中国内蒙古株驯鹿狂蝇蛆（C.trompe CIML）及其成蝇（C．trompe CIMA）线粒体COI种属特异性基因片段长度约为672bp～676bp。种系发生进化树分析显示：第三期幼虫与成蝇两者在核苷酸碱基序列上存在一定差异；它们与同种不同挪威株（C．trompel同源性较为接近：与同属不同种（C．stimulator和C．ulrichii）同源性稍差；与不同属种的羊狂蝇（Oestrusovis）同源性较远，狂蝇科不同属间序列差异明显，差异性在18．6％～23％之间；鹿蝇属不同种间差异性在1．9％～9．9％之间：驯鹿狂蝇不同株间差异性为0．9％。说明生物线粒体COI基因核苷酸序列在一定程度上．可反映出种属及株间在进化上的差异性。     

英汉语言中动物喻人的异同

英汉语言中动物喻人有同亦有异,其异同集中反映在褒贬义、引申义、习语和表达方式上,应根据中西文化的差异,正确把握它们的异同。