Electrochemical studies on Zn/nano-CeO 2 electrodeposited composite coatings

The Zn-CeO 2 composite coatings through electrodeposition technique were successfully fabricated on mild steel substrate. As a comparison pure zinc coating was also prepared. The concentration of CeO 2 nanoparticles was varied in the electrolytic bath and the composites were electrodeposited both in the presence and absence of cetyltriammonium bromide (CTAB). The performance of the CeO 2 nanoparticles towards the deposition, crystal structure, texture, surface morphology and electrochemical corrosion behavior was studied. For characterizations of the electrodeposits, the techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM) were used. Both the additives ceria and surfactant polarize the reduction processes and thus influence the deposition process, surface nature and the electrochemical properties. The electrochemical experiments like potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) studies carried out in 3.5 wt. NaCl solution explicit higher corrosion resistance by CeO 2 incorporated coating in the presence of surfactant. © 2012 Elsevier B.V. All rights reserved.

Efeito de surfactantes na estimativa da densidade bacteriana em amostras de petróleo

Foi examinado o efeito dos surfactantes polisorbato 60 (Tween 60), polisorbato 80 (Tween 80), brometo de cetil trimetil amônio (CTAB) e lauril sulfato de sódio (SDS) na estimativa da densidade de Bactérias Redutoras de Sulfato (BRS) e Bactérias Anaeróbias Heterotróficas Totais (BANHT) em amostras de petróleo. Para a realização dos experimentos, foram selecionadas três amostras com diferentes proporções de óleo e água de forma a representar amostras reais. A primeira amostra contém uma alta proporção de óleo, a segunda uma proporção média e a última amostra uma baixa proporção de óleo. A densidade bacteriana foi estimada através do método do Número Mais Provável (NMP). As concentrações dos surfactantes empregadas neste estudo foram estabelecidas através de estudo anterior. Os resultados demonstram que nas amostras com alta e média proporção de óleo, a adição dos surfactantes não foi favorável a um aumento na quantificação de BRS. Por outro lado, o Tween 60 e o Tween 80 mostraram um aumento significativo na quantificação de BANHT quando aplicados na concentração de 0,01% e 0,03% m/v, respectivamente. O CTAB favoreceu o crescimento de BRS e BANHT na amostra com baixa proporção de óleo quando sua concentração foi de 0,001% m/v e 0,0001% m/v, respectivamente

分子标记技术在甘兰型杂交油菜育种上的研究与应用

本文应用RAPD分标记技术对我国重要的油料作物“杂油59”杂种种子的Fl代杂种的纯度进了技术鉴定，并完善了这一技术，摸索出这一适合于目前生产应用的实用方法，填补了这一技术在油菜作物应用上的空白。用RFLP技术对我国重要的雄性不育材料“陕2A”细胞质进行了分子水平的鉴定，为证明“陕2A”是一类新型的雄性不育材料提供了重要的实验证据。 对甘蓝型油菜采用DNA快速提取法、酚仿法和CTAB法应用于不同的分子标记分析，实验结果显示： CTAB法适用于样品量大，纯度要术高的RFLP技术，酚仿法适用于引物筛选、DNA模板用量大的PCR反应，而快速提取法特别适合于生产上对种子纯度检测，是生产上推广前景很好的实用技术。 对甘蓝型油菜RAPD技术应用当中PCR体系的建立进行了探讨。实验结果显示：热启动对PCR结果的影响至关重要。而Mg++浓度、dNTP浓度、模板浓度、Tag酶用量对反应结果有不同程度的影响。经过反复实验：当PCR各组分按Mg++，2mM;dNTP，200uM;模板浓度，50ng - lOOng时，PCR的结果最好。PCR反应条件经反复实验后确定为：第一个循环：（热启动）94℃，Imin20sec．OoC 2min循环一次;第二个循环：（解链）94℃ 50sec，（退火）40℃ Imin30sec;（延伸）72℃lmin;循环40次。第三个循环：72℃lOmin，循环1次。反应总体积为20ul时最为适用。 用40个lOmer的RAPD随机引物对“杂油59”的2个亲本“垦C8”和“陕3A” 进行RAPD分析，共出现290条带，分布于3530-220bp之间。引物opA-06、opK-03、opK-13、opj-12出现阳性扩增。经重复实验后确定： opK-03的PCR结果重复性最好，该引物序列为：CCAGCTTAGG。用它对两个亲本进行RAPD分析，PCR结果共出现9条带，其中510bp、260bp为二条特征带。在Fl代中这两条特征带重现性很好。用50个商品用种萌发的F1单株进行验证，检测结果为3个个体没有出现510bp的特征带，4个个体没有出现260bp的特征带，有5个个体出现了其它带，纯度为78%，与生产用种的纯度相符。 通过对“杂优59”不同生育时期及不同取样部位作酯酶同工酶电泳方法与RAPD方法相比较，结果显示：RAPD方法可以弥补同工酶方法的缺限。由于它是基于基因水平的分析技术，可以不受环境条件、发育时期、取材部位等客观条件的限制，并具有取样量小、易操作、费用低、灵敏度高、可以检测出亲缘关系相当近的种闾或种内的材料，具有独到的优点。是值得今后在生产上推广的新技术。 用6个雄性不育材料线粒体的特异探针：ALXR 18（线粒体ATPaseα亚基）;COB 640(脱辅基细胞色素-b);COX -I（细胞色素氧化酶亚基-I）;COX -Ⅱ（细胞色素氧化酶亚基-II;PDC - 12（胡萝卜线粒体随机片断）;C2（玉米线粒随机片断），对“陕2A”，Hybrides Polima，Ogura NSL 94/96, Ogura MLCH036, Ogura NSL, Polima, Fu27,Fu38, Anand等9个材料进行RFLP分析，结果显示：用限制性内切酶EcoR I消化后的DNA与探针COB 640杂交，“陕2A”材料在4.5 kb处缺失，与ALXR 18探针杂交，在4.4 kb、4.2 kb处也明显缺失，证明“陕2A”显然不同与其它不育材料。用ALXR l8为探针，与用内切酶Nc01的酶切片断作Sourthern杂交，在RFLP谱带上6.1 kb、2.4 kb、2.5 kb处明显缺带，进一步为“陕2A”是一种新型的甘蓝型油莱雄性不育系提供了证据。

植物高赖氨酸蛋白质的分离和纯化及其N端序列核苷酸探针的合成

禾谷类作物水稻和小麦是人们的主要植物性食物来源．而这些作物种子蛋白质中人类不能合成的必需氨基酸含量不平衡，造成了优质蛋白质的缺乏和人体对蛋白质利用的极大浪费．大约有二分之一的谷类种子蛋白质和四分之一的大豆蛋白质不能被合理地利用。大多数禾本科作物包括水稻和小麦的种子蛋白质中第一限制性氨基酸是赖氨酸，纠正其不平衡现象可大大提商蛋白质的营养价值。本研究在高赖氨酸植物种的筛选、高赖氨酸种子储藏蛋白质的纯化及其基因的分离等方面开展了工作。 选用与禾本科亲缘关系较远的8个植物种为研究材料，它们分别属于榛科，十字花科、胡桃科、豆科、胡麻科和松科。氨基酸组分分析确定豆科和十字花科的三个植物种赖氨酸含量在5.5%以上，其中豆科植物四棱豆(Pso phocarpus tetragonolobus)种子全蛋白赖氨酸含量达7.9%．用5种提取液提取了四棱豆种子的清蛋白、球蛋白和全蛋白。经测定发现0.025M Tris.HCl(pH7.4)提取液提取的清蛋白赖氨酸含量高最．通过自然胶电泳，SDS-PAGB电泳，非变牲IEF和变性IEF／SDS双向电泳，对四棱豆种子清蛋白进行了定性研究。用变性IEF/ SDS双向电泳分析出60多种蛋白质和蛋白质亚基及多肽。研究中改进了等电聚焦电泳纯化蛋白质的方法，经处理的胶板显现出清晰的蛋白质带型，不需染色即可确定带的位置，从切下的胶条中洗脱的蛋白质，其纯度达到双向电泳纯和HPLC纯。用三种电溶方法(SDS-PAGE非变性IEF，变性IEF)纯化出三十一种蛋白质或多肽分子。分别进行了分子量确定和氨基酸组分分析，发现了一个赖氨酸含量高达11.4%的蛋白质，其分子量为18KD，并制备了该蛋白质的抗体，测定了18KD蛋白质N端30个氨基酸残基的顺序，根据这一顺序设计合成了一组17个核苷酸的基因探针．经鉴定单链DNA探针的纯度和总量达到了设计要求。用尿素法与CTAB法结合提取了四棱豆幼苗核基因组DNA，其分子量在50Kb以上，达到了构建GenormicDNA文库的要求．用bamHI EcoRI和HindⅢ三种酶切割提取的DNA，得到了分子量大小不同的片段。 对四棱豆种子蛋白质的定性、高赖氨酸蛋白质的纯化、18KD蛋白N端序列分析及寡核苷酸探针的合成以及GcnomicDNA的提取与酶切，尚未见有资料报道．这些工作为克隆高赖氨酸基因打下了良好的基础，对改良禾本科作物蛋白质品质意义深远．

天山不同海拔高度下长鳞红景天种群遗传多样性分析

长鳞红景天（Rhodiola gelida）属景天科红景天属，多年生草本。主要分布在我国新疆中部天山。在天山一号冰川观测试验站附近的高寒草甸上，从海拔3850m~4010m均有长鳞红景天分布。长鳞红景天是一种重要的药用植物，但目前尚未见到有关其遗传多样性方面的研究报道。本文利用相关序列扩增多态性（sequence-related amplified polymorphism，SRAP）分子标记技术，对新疆天山不同海拔高度3个长鳞红景天种群的遗传多样性，种群内及种群间的遗传变异进行研究，为有效保护和合理利用长鳞红景天物种资源提供理论依据。主要结果如下： （1）基于CTAB法，建立了适合长鳞红景天的DNA提取方法，获得的DNA经琼脂糖电泳和紫外分析仪检测，浓度和质量均较高。该法有利于去除长鳞红景天植物材料中多糖、多酚类等物质，获得的高质量基因组DNA能够满足后续的PCR实验要求。 （2）采用正交实验对影响长鳞红景天SRAP-PCR反应的4个主要因素（Taq酶用量、Mg2+浓度、dNTP浓度、引物浓度）进行优化试验，选出这4个因素的最佳水平组合，建立了长鳞红景天SRAP-PCR最佳反应体系。同时，根据最佳体系筛选出扩增稳定、多态性丰富的SRAP引物。通过梯度PCR确定引物的最佳退火温度，得到了适合长鳞红景天SRAP-PCR反应的最佳扩增程序。 （3）对20对SRAP引物的扩增结果进行统计分析显示：长鳞红景天物种水平的多态位点百分率(P)为96.00 %，Shannon信息指数(I)为0.4484、基因多样性指数(H)为0.2922，表现出较高的遗传多样性水平；在海拔梯度上，长鳞红景天各种群间的遗传多样性水平有一定差异，但没有呈现规律性的变化；AMOVA分子变异分析显示，在总遗传变异中24.76 % 的变异存在于种群间，75.24 % 的变异存在于种群内，种群间的基因分化系数(Gst)为0.1749，表明3个长鳞红景天种群的变异主要存在于种群内，但种群间也出现了一定程度的遗传分化；长鳞红景天3个种群间的基因流为2.3595，遗传距离平均值为0.0981（变化范围：0.0768 ～0.1196），遗传距离较近，说明海拔高度对长鳞红景天的地理隔离较小；相关性分析表明长鳞红景天种群的遗传多样性与各生态因子的相关性均不显著。

Study morphologic, phylogenic relationships DNA barcoding of of identified decapod group (Crustacean) of Persian Gulf and Oman Sea.

Phylogenetic relationships among all described species (total of 12 taxa) of the decapoda, were examined with nucleotide sequence data from portions of mitochondrial gene and cytochrome oxidase subunit I (COI). The previous works on phylogeny proved that the mitochondrial COI gene in crustacean is a good discriminative marker at both inter- and intra-specific levels. We provide COI barcode sequences of commertial decapoda of Oman Sea, Persian Gulf, Iran. Industrial activities, ecologic considerations, and goals of the decapoda Barcode of Life campaign make it crucial that species of the south costal be identified. The reconstruction of evolut phylogeny of these species are crucial for revealing stock identity that can be used for the management of fisheries industries in Iran. Mitochondrial DNA sequences were used to reconstruct the phylogeny of the Penaeus species of marine shrimp. For this purpose, DNA was extracted using phenol- chloroform well as CTAB method. The evolutionary relationships among 12 species of the decapoda were examined using 610 bp of mitochondrial (mt) DNA from the cytochrome oxidase subunit I gene. Finally the cladograms were compared and the resulted phylogenetic trees confirmed that the Iran's species origin is Indo-west pacific species. Iran's species, which were not grouped with the other decapoda taxa seem to always form a sister clade with Indo-west pacific species with strong bootstrap support 100%. The result completely agrees with the previously defined species using morphological characters.However, we still lack any comprehensive and clear understanding of phylogenetic relationships in this group.

A survey on relation of morphological, molecular and phylogenetic structure of zoanthids of the islands located in the Hormoz Strait (Hormoz, Qeshm, Larak, Hengam)

The order Zoantharia (Zoanthids) is one of the most neglected orders of cnidarians in the Persian Gulf. The present study aims to investigate the biodiversity of this order with morphological and molecular examination in the Persian Gulf. For this purpose, 123 colonies of zoanthids with variety of shape and colors have been collected from intertidal and shallow water zone of four islands, i. e. Hengam, Qeshm, Larak and Hormoz. After sampling, morphological characteristics of each specimen were recorded based on in situ photographs. Then DNA was extracted using the cetyl trimethyl ammonium bromide (CTAB) method. Both mitochondrial 16S ribosomal DNA (mt 16S rDNA) and cytochrome oxidase subunit I (COI) gene fragments were amplified and sequenced. The results of preliminary morphological identification integrated with two mitochondrial markers sequencing demonstrated the presence of five different species in this region; Zoanthus sansibaricus, Palythoa mutuki, Palythoa cf. mutuki, Palythoa tuberculosa and Neozoanthus persicus?. Although at first sight, morphological properties were not successful to delineate zoanthid species, they become reliable criteria to identify and delineate species in field studies after molecular identification.

水霉菌总DNA提取方法研究

本实验采用EP管反复冻融和研磨的破壁方式,利用溶菌酶法、CTAB法、改良CTAB法、尿素法、十二烷基硫酸钠(SDS)法等5种方法,分别对5种鱼类致病性水霉菌(寄生水霉、多子水霉、异株水霉及两未定种)的基因组DNA进行提取,并采用紫外分光光度计和ITS区基因(包括5.8SrDNA)PCR扩增对DNA进行了评价。紫外分光光度计检测结果表明,5种方法均可提取到水霉菌DNA,其中改良CTAB法提取的5种水霉菌的DNA产量和质量最高,A260/A280在1.79—1.82之间,浓度为45μg/mL;PCR检测结果表

鱼类饲养对地下水中溶解态磷酸酶的影响

比较了鱼类养殖前后 ,地下水中正磷酸盐 (o P)浓度、碱性磷酸酶活性 (APA)在不同大小颗粒之间的分布、溶解态APA对pH、温度、CuSO4、ZnSO4、EDTA 2Na与表面活性剂 (CTAB与TritonX 10 0 )的应答方式及其动力学特征。养鱼之后 ,玻璃缸水中碱性磷酸酶表现出明显较高的活性 ,且以溶解态为主要存在形式 ,这种效应与鱼类的品种有关 ,溶解态APA的最大反应速度 (Vmax)与米氏常数 (Km)均明显提高 ,最适温度与pH值以及对于Zn2 + 的应答方式亦发生明显改变 ,颗粒结

Discharges and sediments as sources of extracellular alkaline phosphatase in a shallow Chinese eutrophic lake

Total alkaline phosphatase activity (APA) and soluble reactive phosphorus (SRP) concentrations were measured in municipal wastewater, and a shallow Chinese freshwater lake receiving it. Activities of Dissolved alkaline phosphatase ( ADAP) in overlying and interstitial water were also analyzed monthly at three sites for several years. The lake was enriched with SRP and alkaline phosphatase by discharge of the wastewater, indicating that the inclusion of APA for estimating water pollution was reasonable. Annual data showed that APA in coarser fraction was significantly higher at the site receiving more wastewaters, both in surface and overlying water, suggesting that resuspension of enzyme most likely occurred in the basin heavily discharged. ADAP was an order of magnitude higher in the wastewater than those in lake waters, and was generally higher in interstitial water, a feature more striking at the site receiving more discharges. Besides, it was irrespectively inhibited by Na2WO4, L-cysteine and EDTA-Na, but stimulated by Cu2+, Zn2+, CTAB and Triton X-100 in interstitial, overlying and surface waters. This similarity of responding patterns to the stressors indicated an analogy between dissolved alkaline phosphatase in water column and that in interstitial water, supporting the hypothesis that the polluted sediments act as source of dissolved alkaline phosphatase in eutrophic lakes.

Water solubility enhancement of phthalates by cetyltrimethylammonium bromide and beta-cyclodextrin

Water solubility enhancements of six phthalates (five aliphatic phthalates and one phenyl phthalate) by cetyltrimethylammonium bromide (CTAB) and beta-cyclodextrin (beta-CD) were studied at 25 degreesC. The solubilities of these plithalates are remarkably enhanced by CTAB solutions above the critical micelle concentration (cmc). Only marginal enhancement of phthalate solubility was observed in solutions containing CTAB below its cmc and beta-CD at low concentrations (less than 5 mM). The solubility enhancements of the plithalates are proportional to the added amount of CTAB and beta-CD. Partition coefficients of the plithalates between monomeric CTAB surfactant and water (K-MN) and between CTAB micelle and water K-MC) were estimated from the experimental data. The mechanisms of solubility enhancements by CTAB and beta-CD were discussed. A log-linear equation was proposed and evaluated for the solubilization by CTAB below cmc, while the previously proposed linear partitioning model was questioned. The structures of the complexes formed between plithalates and beta-CD were proposed, and the formation constants were estimated. The values of log K-MC, log K-MN, and log Kbeta-CD of the plithalates were found to correlate linearly with the log K-OW of plithalates, with the exception of the solid phenyl phthalate.

Fluorescence pH probe based on microstructured polymer optical fiber

A kind of optical pH sensor was demonstrated that is based on a pH-sensitive fluorescence dye-doped (eosin) cellulose acetate (CA) thin-film modified microstructured polymer optical fiber (MPOF). It was obtained by directly inhaling an eosin-CA-acetic acid mixed solution into array holes in a MPOF and then removing the solvent (acetic acid). The sensing film showed different fluorescence intensities to different pH solutions in a pH range of 2.5-4.5. Furthermore, the pH response range could be tailored through doping a surfactant, hexadecyl trimethyl ammonium bromide (CTAB), in the sensing film. (c) 2007 Optical Society of America.

核酸与电极表面和小分子相互作用的研究

首次用现场红外光谱电化学方法研究了自然状态和热变性的CT DNA在玻碳电极（GCE）表面的电化学过程。发现在-0.2 V-1.3 V的电位范围内，自然状态的CT DNA可有为附在GCE表面，且吸附状态随电极度电位改变。在pH4-9的范围内，热变性CT DNA在GCE表面先发生吸附反应，接着发生氧化反应并从电极表面脱附，氧化过程完全不可逆；但在酸性条件下（pH1.28）反应部分可逆。同时用现场红外光谱电化学法研究了酵母RNA和鲱鱼精DNA在GCE表面的氧化与吸附行为，为研究核酸的氧化反应机理提供进一步的证据。用电化学法和光谱法（UV-vis, CD和FTIR）研究了一系列阳离子染料与核酸的作用，发现阳离子染料可与核酸生成非电活性物质，并获得了它们与核酸的结合常数。发现染料与核酸的结合模式与二者浓度比有关。静电作用，氢键和温度在二者互相作用中起重要作用。CTAB与核酸结合后改变了核酸双螺旋的微环境，CTAB，MG和CT DNA相互作用可以形成一种三无化合物，CTAB-CT DNA-MG。高浓度的NR与CT DNA作用后，在DNA双螺旋的表面聚集，使核酸的构象由B型转变为Z型。

DNA结构的扫描探针显微学研究

1．利用原子力显微镜，我们研究了DNA与邻菲咯琳钻之间的反应。乙醇溶液中DNA复合物的形貌改变很好地说明了静电力在引起DNA凝集中的重要地位。随着醇浓度增加，对应更低的介电常数，静电反应增强。当介电常数降低，平衡离子就会在DNA的磷酸骨架上聚集，并中和负电荷到能引起凝集的程度。2，为了深入认识DNA-表面活性剂复合物的形貌特征，我们对阳离子表面活性剂CTAB引起的DNA凝集体进行了研究。由环状凝集体的体积分析，我们认为DNA发生单分子凝集。除环状体之外，许多不规则的环状体有助于说明DNA环状体的形成过程。部分绕转体和核小体状环状体对应于绕转模型而棒状中间体显示DNA分子也可能采取棒状体到环状体的转化模型。3．DNA分子在形成稳定的凝集体之前会经过一系列的中间体。因为温度是DNA结构的一个重要的决定因素，在其他凝集条件一定时，我们观察了DNA凝集中间体在温度升高时的结构转变。AFM分析得出质粒DNA pBR322的凝集结构受温度的影响很大。低温时，单个分子花束体是DNA分子采取的主要凝集结构。较高温度时，分子变得舒展，但链上有许多可能利于多分子凝集的小环。继续升高温度，DNA分子大范围地发生分子间的单中心、交联。4．在Mg2+，Ca2＋，Sr2和Ba2+分别作为DNA在云母表面的平衡离子时，我们观察了DNA分子在云母表面扩散平衡或被动力俘获的形貌特征。末端距和伸展长度可由原子力显微镜的数据分析结果得到。实验结果表明当Mg2＋，Ca2+和Sr2+为平衡离子时，DNA分子能够在云母表面扩散平衡。然而Ba2+作用时，严重交接的DNA结构说明DNA分子不易在云母表面反应平衡，俘获的程度也随实验条件而改变。在醇溶液中，我们还观察了B-A构象转变对平衡离子种类的依赖关系。四种碱土金属引起B-A构象转变的能力不同，其中Sr2-导致B-A构象转变的程度最大。

铁氰化钴修饰电极的制备、表征及电催化性能的研究

多核过渡金属铁氰化物修饰电极的研究在电催化、电色显示器件、能量存储、离子识别等方面具有重要的意义。本文采用了电化学的循环伏安法（CV）、旋转圆盘电极技术（RDE）、傅立叶变换红外光谱法（FTIR）和扫描电子显微镜技术（SEM），系统研究了一类铁氰化物—铁氰化钴修饰玻碳（CoHCF／GC）电极的制备方法及其对神经递质多巴胺（DA）的电催化作用以及修饰溶液中一种阳离子表面活性剂十六烷基三甲基溴化铵（CTAB）的加入对所制备的CoHCF／GC电极的电化学性能和电催化性能的影响。主要内容和结论如下：1．改进了CoHCF／GC电极的制备方法。新方法具有简单易行、不受修饰物浓度干扰、修饰时间短、修饰量易于控制等优点，且制备的CoHCF粒径小、结构明确、电化学性能稳定。2．研究了CoHCF／GC电极对DA氧化的电催化性能。采用RDE测定了CoHCF／GC电极对DA的电催化氧化的动力学参数。结果表明用新方法制备的修饰电极对DA氧化有更好的电催化性能。3．研究了在修饰溶液中加入临界浓度的CTAB对所制备的CoHCF／GC电极的影响。CV的研究结果表明，CTAB的加入，基本不影响CoHCF／GC的氧化还原峰峰电位，却使其氧化还原峰峰电流明显增大，且使所制得CoHCF／GC电极对DA氧化表现出不同的电催化行为。FTIR研究表明，CTAB不吸附在电极表面，不改变COHCF膜的化学组成和结构。SEM研究结果表明，CTAB的加入使所制备的CoHCF膜长得更快，更厚，使CoHCF粒子长得更大。因此，可得出结论为CoHCF粒子的大小是影响其对DA不同的电催化行为的主要因素。4．用RDE技术测定了有、无CTAB情况下制备的CoHCF／GC电极对DA的电催化反应的动力学参数。结果表明，有CTAB时制备的CoHCF／GC电极对DA的表观动力学常数kΓ比没有时的要大。