1-(3-磺酸基)丙基哌啶十二烷基苯磺酸在CO_2捕集中的应用

合成了一种具有表面活性功能的离子液体1-(3-磺酸基)丙基哌啶十二烷基苯磺酸([PIPS]DBSA),采用FT-IR,1H NMR和元素分析等方法对产物进行表征,并将其用于促进CO2水合物的生成,考察[PIPS]DBSA对CO2水合物生成过程中温度和压力的影响.实验表明在温度4℃—6℃时,300 mg·L-1[PIPS]DBSA溶液中CO2的相平衡压力比700 mg·L-1的十二烷基苯磺酸钠(SDBS)溶液的相平衡压力下降了13.6%—14.96%.在4℃时,300 mg·L-1[PIPS]DBSA溶液中CO2压力稳定所用的时间与700 mg·L-1SDBS溶液相比减少了50 min,表明[PIPS]DBSA对CO2水合物的形成具有良好的促进作用.     

酶法高效转化苯乙酮酸合成L-苯甘氨酸

L-苯甘氨酸是合成多种抗生素和抗癌药物的重要中间体,目前主要通过化学法合成.利用蜡样芽孢杆菌来源的亮氨酸脱氢酶(LeuDH)催化苯乙酮酸的还原氨基化合成L-苯甘氨酸,并偶联甲酸脱氢酶(FDH)进行辅酶再生,建立了一种新型的苯甘氨酸生物合成方法.结果表明,该辅酶再生体系可有效地用于L-苯甘氨酸的合成,且没有副产物残留,辅底物甲酸铵还可提供还原氨基化所需NH4+,随后对酶转化条件进行优化,最适转化条件为苯乙酮酸60 g/L,甲酸铵50.4 g/L,LeuDH 4 U/mL,FDH 2 U/mL,NAD+浓度0.14 g/L,p H 8.0以及30℃.在最优条件下,1 L的转化体系中,转化反应5 h,苯乙酮酸转化率达到99%,L-苯甘氨酸产量60.2 g/L,ee值99%.本研究为L-苯甘氨酸的工业生产提供了一种更加简单、高效、经济的生物合成途径.(图8表4参27)     

(N-[2-(2-氧-1-咪唑烷基)乙基]-N '-苯基脲(EDU)对环境臭氧胁迫下的水稻和小麦生长的影响

通过对作物定期喷施不同浓度(0、150、300和450 mg·L-1)的N-[2-(2-氧-1-咪唑烷基)乙基]-N'-苯基脲(ethy lenediurea,EDU)溶液,研究EDU对环境O3胁迫下水稻“粤晶丝苗2号”(Oryza sativa L.Yuejingsi 2)和小麦“北农9549”(Triticum a...     

一种提取氧化葡萄糖酸杆菌山梨糖脱氢酶的简单方法

利用表面活性剂TritonX-100建立一种提取和测定氧化葡萄糖酸杆菌（Gluconobacter oxydans)L-山梨糖脱氢酶（L-sorbose dehydrogenaseSDH)活性的简便方法，最适提取条件为：TritonX-100浓度ψ（Triton)/%=0.3。提取温度θ=4℃，处理时间t/h=6-10h；用于提取的菌悬液D550nm范围0.090-0.252。该方法提取效率为细胞碎片法的97.83%。图2表2参7     

氰戊菊酯对河川沙塘鳢幼鱼的毒性效应

采用静水生物测试法,研究了氰戊菊酯(fenvalerate,FEN)对河川沙塘鳢(Odontobutis potamophila)幼鱼的毒性效应.结果显示,FEN对河川沙塘鳢幼鱼的24、48、72和96 h(t)的半数致死质量浓度ρ(LC50)(95％置信区间)分别为(3.19±1.38)、(1.66±1.02)、(0.98±0.69)和(0.70±0.49) μg·L-1,变化规律符合指数衰减模型ρ(LC50) =0.915 1 +15.012 3 ×exp(-0.075 8 ×t)(r=0.996 2),安全浓度为(0.13±0.97) μg·L-1.半数致死时间t(LT50)表现出显著的剂量[ρ(FEN)]效应,可用方程t(LT50) =2 653.467 6 ×exp[-5.590 4 ×ρ(FEN)]+56.378 7 ×exp[-0.209 5×ρ(FEN)](r=0.999 4)对其进行拟合.双因素方差分析显示,肝脏过氧化氢酶(CAT)、超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量随FEN浓度的增加和暴露时间的延长而均呈显著变化(P＜0.05),但两个因素的交叉影响不显著(P＞0.05).暴露24 h时,4μg· L-1浓度组SOD和CAT活性达到峰值,随后开始下降,而此时各浓度组MDA含量无显著变化(P＞0.05),48和96 h时,4、6和10 μg·L-1浓度组MDA含量则表现为显著上升.暴露时间和FEN浓度的交互作用对鳃Na+ /K+-ATP酶活性影响显著(P＜0.05),暴露24、48和96 h时,高浓度(6和10 μg·L-1)组Na +/K+-ATP酶活性均呈现显著下降;上述指标可较好地用于评价FEN的毒性效应.组织病理观察发现,FEN污染对河川沙塘鳢幼鱼的鳃、肝脏均造成严重损伤:鳃丝紊乱,上皮细胞增生,柱状细胞破裂;肝细胞实质空泡化,胆管内皮细胞肥大、融合.     

苯并[a]芘和菲对缢蛏血细胞DNA损伤的研究

为研究苯并[a]芘和菲对缢蛏的毒性效应,将缢蛏(Sinonovacula constricta)分别暴露于浓度为0.45 mg·L-1、0.15 mg·L-1、0.05 mg·L-1苯并[a]芘溶液和0.45 mg·L-1、0.15 mg·L-1、0.05 mg·L-1菲的溶液中,采用单细胞凝胶电泳实验(彗星实验)技术检测不同暴露时间缢蛏血淋巴细胞的DNA损伤程度,对照组为清洁海水。结果显示,高浓度(0.45 mg·L-1)苯并[a]芘溶液和(0.45 mg·L-1)菲溶液在短期(7 d)内即可导致缢蛏血细胞显著的DNA损伤,并且随苯并芘[a]和菲浓度的增大和暴露时间的延长,DNA损伤程度增加。21 d恢复实验后,各浓度组DNA损伤又均有不同程度的恢复,但中高浓度组(0.45 mg·L-1和0.15 mg·L-1)与对照组仍显著性差异。两种多环芳烃物质对缢蛏血细胞的DNA损伤作用均存在较显著时间-剂量-效应关系。其中,苯并芘[a]对缢蛏血细胞的DNA损伤作用要高于菲。     

在线固相萃取-高效液相色谱-紫外检测法测定污水处理厂水样中直链烷基苯磺酸盐(LAS)

直链十二烷基苯磺酸盐(LAS)是合成洗涤剂中含有的重要阴离子表面活性剂之一.LAS进入水体后,与其它污染物结合形成分散胶体颗粒,对工业污水和生活污水的物理、化学和生化特性都有很大影响,并产生潜在的危险.GB 8978—1996《中华人民共和国国家标准污水综合排放标准》规定LAS一级排放限量为5 mg.L-1[1].     

膨润土负载纳米铁用于降解水体中阿莫西林

采用液相还原法合成膨润土负载纳米铁(B-nZVI)和纳米铁(nZVI)并用于降解水中的阿莫西林.实验结果表明,无论是单独nZVI还是B-nZVI都能有效降解阿莫西林.在25 mL浓度为20 mg.L-1的阿莫西林溶液中加入0.1 g的B-nZVI(其中nZVI的含量为0.05 g),溶液的初始pH值为6.65,摇床的振荡速率为250 r.min-1,反应温度为25℃,反应时间为120 min的条件下,B-nZVI对阿莫西林的降解效率高达93.1%,在此实验条件下,单独nZVI(0.05 g)对阿莫西林的降解效率只有82.3%,这是由于膨润土对nZVI起到分散作用,从而使B-nZVI的反应活性得到提高.降解动力学研究表明,B-nZVI对阿莫西林的降解过程符合表观一级反应动力学规律,相关系数R2均大于0.945.B-nZVI可多次重复用于降解阿莫西林.     

苯丙氨酸解氨酶的分子生物学研究进展

苯丙氨酸解氨酶 (Ｐｈｅｎｙｌａｌａｎｉｎｅａｍｍｏｎｉａｌｙａｓｅ ,ＰＡＬＥ .Ｃ .4.3 .1.5 )是一种只存在于植物及微生物细胞内的酶 ,主要分布于高等植物如小麦、大豆、玉米、土豆及酵母[1] 、真菌[2 ] 、链霉菌[3]中 .在 ｐＨ 8.8时 ,ＰＡＬ催化苯丙氨酸脱氨生成肉桂酸和氨 ,当过量的氨存在 ,如 ｐＨ 10时 ,ＰＡＬ催化肉桂酸和氨 ,氨化加成生成Ｌ 苯丙氨酸 (Ｌ ｐｈｅｎｙｌａｌａｎｉｎｅ) .利用ＰＡＬ这种逆向催化特性转化肉桂酸生产Ｌ Ｐｈｅ ,已在国内外投入商业规模开发 ,成为当前生物化工领域研究与开发的热点 .Ｌ Ｐｈｅ是人…     

Ce-MCM-41分子筛用于臭氧氧化对氯苯甲酸的活性评价

通过水热法合成了铈掺杂MCM-41(Ce-MCM-41)介孔分子筛,并将其用于臭氧氧化水中对氯苯甲酸(p-CBA).小角X射线衍射(XRD)、氮气吸附-脱附(BET)、紫外可见漫反射光谱(UV-Vis DRS)、透射电镜(TEM)表征结果表明,铈成功进入MCM-41分子筛骨架,以正四面体形式存在,且Ce-MCM-41保持了纯硅MCM-41有序的介孔结构,具有较高的比表面积;铈的掺杂显著提高MCM-41催化臭氧氧化对氯苯甲酸的活性,反应60 min后,TOC去除率由MCM-41的63%提高到86%(Si/Ce=60),而单独臭氧氧化仅为52%;铈的溶出仅为0.085 mg.L-1,较同样负载量的铈负载Ce/MCM-41的溶出(0.44 mg.L-1)有较大减少.催化剂重复使用3次后仍保持较高的活性,这表明Ce-MCM-41具有较好的活性和稳定性,是一种有前景的臭氧氧化催化剂.     

天南星（Arisaema erubescens Schott）对钉螺（Oncomlania hupensis）的毒杀作用

近年来,血吸虫病在我国又有回升的势头,采用植物灭螺进而消灭血吸虫病是控制血吸虫病蔓延的有效方法.实验研究了一种新型灭螺植物——天南星(ArisaemaerubescertsSchott)的灭螺效果和机理.采用天南星植物水浸液用于灭螺(Oncomlaniahupensis)实验,并检测天南星处理后钉螺肝脏生理生化指标的变化.结果显示,天南星全株均具有较强的灭螺效果,其中块茎灭螺效果最好:0.1%块茎水浸液处理3天后钉螺死亡率达88.4%,5天后达100%;天南星不同部位的灭螺效果为:块茎>叶>茎.天南星块茎水浸液处理钉螺后,随处理浓度的增加和处理时间的延长,钉螺肝脏丙二醛(MDA)含量显著升高,而过氧化物酶(POD)和超氧化物歧化酶(SOD)活性显著降低.天南星水浸液可引起钉螺肝细胞的过氧化损伤,导致其抗氧化能力下降,从而降低了其代谢和解毒功能.研究结果表明,天南星是一种具有良好灭螺效果的植物,可成为构建植物群落生态工程灭螺林新的物种资源.     

安徽沿江地区4种蛇的染色体组型、C带和Ag-NORs研究

本文报道游蛇亚科４种蛇的核型、Ｃ带和ＡｇＮＯＲｓ,结果：黄链蛇２ｎ＝４６．虎斑游蛇２ｎ＝４０,第４号染色体（Ｎｏ．４）有随体．鸟梢蛇和紫灰锦蛇２ｎ＝３６,鸟梢蛇的Ｎｏ．５短臂近着丝粒区有一次缢痕．虎斑游蛇Ｎｏ．５为性染色体,其余３种的性染色体为Ｎｏ．４．这４种蛇均为ＡＦ＝５０;Ｃ带型的种属性特征明显,其中紫灰锦蛇的端粒型Ｃ带特别发育,其余三种以着丝粒Ｃ带较发达．黄链蛇、虎斑游蛇和紫灰锦蛇的Ｗ染色体Ｃ带正染呈现整条异染色质化;银染结果４种蛇均只显示一对ＮＯＲｓ,但其分布不同,其中虎斑游蛇ＮＯＲｓ呈异态现象．文章讨论了核型的演化和次缢痕、ＮＯＲｓ及Ｃ带的关系     

Studies on enzymes associated with calcification of the cuticle of the hermit crab Clibanarius olivaceous

In the anomuran Clibanarius olivaceous Henderson, the cuticle of the cephalic and thoracic regions is calcified, while that of the abdominal region is uncalcified. Histochemical observations have been made on the possible enzymes involved in the process of calcification of cuticle. The calcified regions show the presence of enzymes such as phosphorylase, alkaline phosphatase and carbonic anhydrase. The possible role of phosphorylase in calcification may be production of phosphoric esters, which form the required substrate for alkaline phosphatase. The latter appear to be associated with the production of phosphate ions from phosphoric esters. The carbonic anhydrase may be associated with the production of carbonate ions. The suggestion that these enzymes are involved in the process of calcification is further supported by experimental evidence of inhibition of the action of enzymes by enzyme inhibitors. The inhibition of enzymes leads to reduction in the amount of calcium added to the cuticle.This paper formed part of a thesis approved for the award of Ph. D. degree of the University of Madras.     

Metabolic relationships between fatty alcohol and fatty acid in the liver of Squalus acanthias

The high speed supernatant fraction of a homogenate of Squalus acanthias L. liver catalyses the oxidation of oleyl alcohol to oleic acid by an NAD-dependent process. Reduction of fatty acid to fatty alcohol could not be demonstrated. Liver lipids of S. acanthias contain about 60 and 40% of triglycerides and diacyl glyceryl ethers, respectively, with only traces of wax esters. Serum lipids contain 28, 15 and 26% of triglycerides, diacyl glyceryl ethers and wax esters, respectively. Cell-free fractions of S. acanthias liver catalyse the formation of wax esters by an ATP¹-dependent process. The bulk of wax ester synthesis occurs in the high-speed supernatant fraction of liver. The rate of formation of the ester bond in wax esters is comparable to the rate of synthesis of ester bonds in triglycerides, and greatly exceeds the rate of formation of the ether bond in diacyl glyceryl ethers. Results are discussed in terms of possible factors controlling the levels of neutral lipids in S. acanthias.     

Positive effects of the introduced green alga, Codium fragile ssp. tomentosoides, on recruitment and survival of mussels

The green macroalga, Codium fragile ssp. tomentosoides, is an important component of sheltered low-shore assemblages on breakwaters along sandy shores in the northern Adriatic Sea. Macroscopic thalli of C. fragile are not perennial, but develop from propagules and/or undifferentiated forms in early spring, when the dominant native space-occupier, the mussel Mytilus galloprovincialis, recruits. By mid-summer, rapid growth of C. fragile leads to the formation of a dense canopy. We investigated the effects of juvenile and adult thalli of C. fragile on recruitment, survival and growth of mussels. Two experiments tested the hypotheses: (1) that recruitment of mussels is greater within patches of juvenile thalli (primordia) of C. fragile than on adjacent bare surfaces; (2) that the presence of a canopy of C. fragile affects the survival and growth of mussel recruits. The number of recruits of mussels was significantly larger within clumps of primordia of C. fragile than on bare surfaces. The removal of the canopy of C. fragile affected negatively the density of mussels after 2 months from the start of the experiment, but there were no effects on the mean size of individuals, nor on the size–frequency distribution. The same trend persisted after 4 months from the start of the experiment. These results show that re-colonisation of space by mussels is enhanced by C. fragile. Given that mussels, in turn, have the potential to reduce recruitment rates of C. fragile, quick recovery of mussel beds after disturbances could be crucial for controlling the abundance of this alga on breakwaters. Results also suggest that the effects of introduced species on native assemblages can be explained only through studies encompassing different life-stages of interacting organisms.     

Estuarine management strategies and the predictability of ecosystem changes

The Dutch Delta Region (S-W Netherlands) originally consisted of interconnected estuaries, interfacing the rivers Rhine, Meuse and Schelde with the North Sea. The ecosystems were immature, with physical rather than biological control of population dynamics. Main functions were shipping and shellfisheries. An emergent function of the interconnected estuaries was the buffering and upgrading of river-borne substances before they entered the sea. Execution of the Delta Project in the period 1960–1986 resulted in isolation of several water systems disconnected from rivers and sea, and loss of gradients within these systems. Population dynamics were now controlled by chemical and biological rather than physical factors. Vulnerability to external perturbation increased. These changes also affected the buffering capacity, i.e. reduced the utility of the area as stabiliser of the geosystem. Recreational use and appreciation of natural values increased, potentially conflicting with shipping and shellfisheries. Retrospective analysis of the environmental policy and management revealed three consecutive strategies in the Delta Project. 1. Reactive one-issue management, focusing on safety against flooding only. This strategy aimed at complete closure of the estuaries thus transforming them into fresh water lakes. It has destroyed feed-backs and buffering between coastal and inland waters. This strategy has not promoted sustainable development and has increased the vulnerability of the area to future catastrophes. 2. Protective bio-ecological management focused on the preservation of existing values of landscape and environment, and resulted in the maintenance of saline conditions and preservation of marshes by shore protection measures. The drawback of this passive orientation to existing values ?where they are now? is the necessity of continuous intensive care because the natural adaptive ability is not being restored. 3. Constructive geo-ecological management is based on understanding functional properties within and between ecosystems as integrated elements of the landscape structure. This strategy aims at environmental protection, restoration and development of values ?where they must be?. Re-establishment of gradients by e.g. re-introducing tidal influence and by restoring salt marshes should contribute to sustainable development.     

几种天敌对麦蚜蜜露的行为反应

麦长管蚜和禾谷缢管蚜蜜露的主要糖分为果糖、葡萄糖、蔗糖及两种未知糖分．其中前者以蔗糖含量最高，后者则不含蔗糖．其游离氨基酸种类基本相同，但后者蜜露中未鉴定出苏氨酸；除丙氨酸和组氨酸外，麦长管蚜中各类氨基酸的含量明显高于禾谷缢管蚜，其中单头麦长管蚜日分泌氨基酸量以亮氨酸和丙氨酸最高，分别达到了0．204 7ng和0．137 7ng，而禾谷缢管蚜以丙氨酸和亮氨酸最高，分别达到了0．154 3ng和0．102 5ng．随着蜜露含量的增加，各天敌的搜索与滞留时间显著延长，但逐渐趋于平缓，基本符合逻辑斯蒂增长．燕麦蚜茧蜂在两种蚜虫蜜露上的搜索与滞留时间差异显著，而瓢虫与草蛉类的搜索与滞留时间差异不显著，说明蜜露对捕食性和寄生性天敌的影响不同．图3表1参13     

米氏凯伦藻对蒙古裸腹溞的毒性及致毒途径分析

米氏凯伦藻(Karenia mikimotoi Hasen)是一种典型的鱼毒性赤潮藻,近年来在我国频繁爆发,给水产养殖业带了严重的经济损失.在实验室条件下,采用混合培养、隔离培养等手段研究了米氏凯伦藻及不同细胞组分对枝角类蒙古裸腹溞(Moina mongolica)摄食与生存的影响,分析了其致毒途径.结果表明,随着混合...     

Analyse von Wachstumskurven von Heterostegina depressa (Foraminifera: Nummulitidae)

Chamber formation in individuals of the large foraminifer Heterostegina depressa was studied with the intention of explaining the different shapes of growth curves established for groups of individuals. The material was derived from clone cultures and from the natural habitat. Chamber formation was observed by daily control of many individuals. The growth increments of a group of individuals depend mainly upon the frequency of chamber formation of the individuals, they also depend upon the percentage of growing individuals present and the sizes of chambers. Within a prolifically growing group, each individual builds a new chamber every second or third day, and 81 to 86% exhibit chamber-building activities. Further features of quickly growing individuals are: formation of chambers in a regular sequence, and short periods of rest between long periods of growth. During low illumination intensity and in darkness, growth of H. depressa may cease for several months (up to 81/2 months). Cessation of growth is connected with a marked reduction in all other physiological processes. After month-long inhibition of growth, different individuals responded with different growth behaviour under the same environmental conditions. For example, smaller individuals needed longer periods of physiological regeneration before building new chambers. Prior darkexposure resulted in intermittent growth in many individuals. Periods of rest were followed by periods of unusually intensive growth. Lower temperature resulted in a reduced frequency of chamber formation. The size of chambers, however, was not influenced; accordingly the shape of the test did not vary. Immediately after multiple fission, rapid growth begins. Growth curves of H. depressa, therefore, do not show initial periods of slow growth which is characteristic for general exponential growth. H. depressa exhibited sigmoidal growth curves only after periods of growth inhibition; it displayed typical regenerative growth. During these periods, up to 4 chambers in 4 days, or 9 chambers in 12 days, were built by 11-month-old individuals.     

模拟水深和氮添加对三江平原湿地植物功能性状的影响

水深和氮素是影响湿地植物生长的关键因素,研究两者对功能性状的影响有助于预测未来环境变化下湿地植物的生长与分布趋势.以三江平原沼泽湿地3种优势植物(漂筏苔草Carex pseudocuraica、毛苔草Carex lasiocarpa和燕子花lris laevigata)为研究对象,设置3个水深(0、5、15 cm)和3...