氢气定容燃烧模拟实验装置设计与应用

设计了氢气定容燃烧模拟实验装置,利用纹影法在此装置中进行了无隔板和带隔板条件下的氢气空气预混合物燃烧特性研究。结果表明,该装置可模拟氢气、空气预混合物的自燃。本文实验条件下,无隔板实验中,球形火焰两端出现两股火焰;氢气空气预混合物的自燃首先发生在球形火焰前锋与两侧壁面的夹角区域。带隔板实验中,2种方案都可实现自燃;其中第2种方案可有效阻断火焰从上燃烧室传播到下燃烧室,进而实现自燃。     

重金属铅对鲫鱼血清抗氧化能力的影响

[目的]研究重金属铅对鲫鱼抗氧化能力的影响。[方法]用0、0．01、0．05、0．10、0．50、1．00mmol／L的含铅水溶液处理鲫鱼,比较不同处理鲫鱼血清过氧化氢含量、过氧化氢酶和髓过氧化物酶活力。[结果]低浓度铅（0．01mmol／L）对鲫鱼血清CAT活力具有一定的促进作用,高浓度铅对鲫鱼血清CAT活力具有抑制作用;鲫鱼血清中H2O2含量随铅离子处理浓度的升高呈上升趋势,但1．00mmol／L铅离子处理组鲫鱼血清H2O2含量低于0．50mmol／L铅离子处理组;较低浓度的铅（0．01、0．05mmol／L）能够提高鲫鱼血清MPO活力,高浓度铅则抑制鲫鱼血清MPO活力。[结论]该研究为鱼类生存环境重金属污染的定量分析提供了参考。     

Effects of temperature and hydrogen peroxide on mycelial growth of eight Pleurotus strains

Effective use of hydrogen peroxide as a chemical sterilant in mushroom production and selection of cultivable mushroom strains for tropical conditions require knowledge of the genetic diversity in the tolerance of the strains to hydrogen peroxide and to high temperatures. Therefore, three experiments were conducted to examine the sensitivity of Pleurotus mycelium to temperature and hydrogen peroxide. In Experiment 1, eight Pleurotus strains, which included two Pleurotus sajor-caju strains, three Pleurotus ostreatus strains, Pleurotus salmoneo stramineus, Pleurotus cornicopae and Pleurotus eryngii were cultured aseptically on agar at 25, 30 and or 35 °C. In Experiment 2, the eight strains were cultured aseptically on agar at six hydrogen peroxide concentrations (0–0.1%, v/v) at 27 °C. In Experiment 3, P. sajor-caju strain 1, a fast growing strain, was cultured non-asceptically at six hydrogen peroxide concentrations (0–0.1%, v/v) at 27 °C. In Experiment 1, mycelial growth was maximal at 25–30 °C, whereas a temperature of 35 °C was detrimental to mycelial growth except in one strain. At the highest temperature tested (35 °C), the relative mycelial growth rate (% of maximum) ranged from 6 to 91%, indicating marked differences in tolerance of the strains to high temperature. In Experiment 2, the mycelial growth rate in all strains increased when hydrogen peroxide was increased from 0 to 0.001% (v/v), and then decreased with further increments in hydrogen peroxide concentration. The strains differed markedly in sensitivity to hydrogen peroxide. The hydrogen peroxide concentration associated with 50% reduction in maximum mycelial growth rate due to toxicity (EC₅₀) ranged from 0.009 to 0.045% (v/v). It was noted that P. sajor-caju strain 1 which was the most tolerant strain to high temperature was also the most tolerant to high hydrogen peroxide concentration. In Experiment 3, involving non-aseptic culture of P. sajor-caju strain 1, bacterial growth was observed at concentrations ≤0.016%, whilst the upper hydrogen peroxide concentration limit for fungal growth was 0.025% (v/v). The highest hydrogen peroxide concentrations 0.016% (v/v) and 0.025% (v/v) in which bacteria and fungi, respectively, were observed to grow were within the concentration range 0.009–0.028% (v/v) that was found in Experiment 2 to cause a 50% reduction in mycelia growth in six of the eight Pleurotus strains tested. Use of hydrogen peroxide as a chemical sterilant in conjunction with strains highly tolerant of its toxicity offers a very cheap method of producing spawn as well as the mushrooms, and opens up opportunities for poor rural people.     

拟南芥响应过氧化氢突变体的筛选及遗传分析

利用甲基磺酸乙酯(EMS)诱变获得的拟南芥突变体库筛选过氧化氢(H2O2)敏感突变体,以期为研究氧化胁迫的分子机制提供遗传材料.从该突变体库中筛选出一株H2O2敏感突变体hps12(hydrogen peroxide sensitive 12).表型分析发现,hps12突变体植株矮小,果荚较短,并且在4 mmol/L H2O2处理下hps12的子叶变绿情况明显低于野生型(WT),突变体的离体叶片在10 mmol/L H2O2处理下相比WT表现出更为明显的衰老症状.进一步遗传学分析表明,该突变体为单基因隐性突变.     

氟污染对玉米幼苗生长及生理特性的影响

为探讨氟污染对农作物的影响,以玉米为供试材料,采用砂基培养的方法,研究了不同浓度的氟(F)对玉米幼苗形态、生物量、光合参数、叶绿素含量、抗氧化酶活力以及丙二醛含量的影响。结果表明,与对照相比,低浓度F(≤0.25mmol·L-1)对玉米幼苗生长无明显抑制现象;随着溶液中F浓度的增加,玉米幼苗生长显著受到抑制,叶长、株高生长变慢,叶面积减小;根系和地上部干物质积累下降;叶片中叶绿素合成受阻,光合速率降低;同时丙二醛(MDA)含量增加;过氧化物酶(POD)活性明显升高,而超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性均表现出一定的下降趋势。说明氟的存在不利于植物的正常生长,研究结果还为进一步揭示氟污染机理以及氟污染的综合治理提供了理论依据。     

盐酸硫胺的主客体作用研究：[CuCl4]（thiamH）的合成、结构及其SOD活性

在甲醇体系中合成了化合物[CuCl4]（thiamH）（thiamH为盐酸硫胺阳离子）,并通过元素分析、红外光谱对其进行了表征,同时还进行了X—ray单晶结构测定．晶体属于单斜晶系,P21／n空间群,晶胞参数a=0．948（2）nm,b=1．685（3）nm,c=1．203（2）nm,β=107．25（3）°,V=1．835（6）nm^3,Z=4,μ=1．893mm^-1,Dc=1．707g·cm^-3,F（000）=956,R1=0．0249,ωR2=0．0655．此外,用邻苯三酚自氧化法测定了标题化合物对超氧阴离子O2^-的催化作用．结果表明,化合物具有良好的超氧化歧化酶（SOD）活性,其IC50为12．46μg·mL^-1．     

外源抗坏血酸和H2O2对油茶离体叶片衰老的效应

以１、５ｍｍｏｌ／Ｌ抗坯血酸和０．１、０．５ｍｍｏｌ／Ｌ过氧化处理油茶叶片。结果表明,抗坏血酸可以明显提高油茶叶片的抗坏血酸过氧化物酶和过氧化氧酶活性,同时减少丙二醛的含量。     

有机废水制取氢气的研究现状与展望

概括了国内外厌氧发酵制取氢气的研究进展,并对厌氧发酵制取氢气所需的条件、原理、影响因子、不同方法进行了评述。结果表明:乙醇型发酵是目前最好的产氢类型,生物制氢技术具有良好的发展前景。     

水牛慢性氟中毒X线诊断的研究

本试验将７０头水牛分为Ⅰ组（３２头来源于氟值水平正常地区的水牛）、Ⅱ组（１４头来源于氟污染地区但未见有临诊症状的水牛）和Ⅲ组（２４头来源于污染地区且有临诊症状的水牛），并对所有水牛进行了骨矿物质含量和１７项生化指标的检测。骨矿物质含量在Ⅰ组与Ⅱ组间、Ⅰ组与Ⅱ＋Ⅲ组间差异极显著（Ｐ＜０．０１），Ⅰ组与Ⅲ组间差异显著（Ｐ＜０．０５），Ⅱ组与Ⅲ组间差异不显著（Ｐ＞０．０５），Ⅱ组Ⅲ组水牛骨Ｘ线变化可归为中度氟骨症。Ⅰ组与Ⅱ组间血清ＡＣＰ、Ｔ－Ｐ、ＡＬＢ、Ｃａ＋＋、Ｍｇ＋＋、Ｋ＋、ＨＰＯ４２－、Ｆ－和尿Ｆ－的差异极显著（Ｐ＜０．０１），血清ＨＹＰ的差异显著（Ｐ＜０．０５）；Ⅰ组与Ⅲ组间血清ＡＣＰ、Ｔ－Ｐ、ＡＬＢ、ＨＹＰ、Ｃａ＋＋、Ｍｇ＋＋、Ｋ＋、ＨＰＯ４２－、Ｆ－及尿Ｆ－差异极显著（Ｐ＜０．０１），血清ＬＤＨ差异显著（Ｐ＜０．０５）；Ⅰ组与Ⅱ＋Ⅲ组间血清ＡＣＰ、Ｔ－Ｐ、ＡＬＢ、ＨＹＰ、Ｃａ＋＋、Ｍｇ＋＋、Ｋ＋、ＨＰＯ４２－、Ｆ－及尿Ｆ－差异极显著（Ｐ＜０．０１）；Ⅱ组Ⅲ组间所有生化指标均无显著性差异（Ｐ＞０．０５）。Ｘ线检查和生化指标的测定具有一致性。