Isolation and characterization of a marine magnetotactic spirillum axenic culture QH-2 from an intertidal zone of the China Sea

Magnetotactic bacteria (MTB) are ubiquitous in aquatic habitats. Because of their fastidious requirements for growth conditions, only very few axenic MTB cultures have been obtained worldwide. In this study, we report a novel marine magnetotactic spirillum axenic culture, designated as QH-2, isolated from the China Sea. It was able to grow in semi-solid or liquid chemically defined medium. The cells were amphitrichously flagellated and contained one single magnetosome chain with an average number of 16 magnetosomes per cell. Phosphate and lipid granules were also observed in the cells. Both rock magnetism and energy-dispersive X-ray spectroscopy characterizations indicated that the magnetosomes in QH-2 were single-domain magnetites (Fe3O4). QH-2 cells swam mostly in a straight line at a velocity of 20-50 mu m/s and occasionally changed to a helical motion. Unlike other magnetotactic spirilla. QH-2 cells responded to light illumination. As a consequence of illumination, the cells changed the direction in which they swam from parallel to the magnetic field to antiparallel. This response appears to be similar to the effect of an increase in [O-2]. Analysis of the QH-2 16S rRNA sequence showed that it had greater than 11% sequence divergence from freshwater magnetotactic spirilla. Thus, the marine QH-2 strain seems to be both phylogenetically and magnetotactically distinct from the freshwater Magnetospirillum spp. studied previously. (C) 2010 Elsevier Masson SAS. All rights reserved.

Genetic improvement on Chinese shrimp (Fenneropenaeus chinensis): growth and viability performance in F1 hybrids of different populations

Fenneropenaeus chinensis distributed in the Yellow Sea and Bohai Sea of China and the west coast of the Korean Peninsula. Different geographical populations represent potentially different genetic resources. To learn further the characteristics of different geographical population, crosses among two wild and three farmed populations were produced. The two wild populations were from the Yellow Sea and Bohai Sea (WYP), and the west coast of the Korean Peninsula and coast (WKN). The three farmed populations included the offspring of first generation of wild shrimp from coast in Korea (FKN), the Huang Hai (the Yellow Sea in Chinese) No.1 (HH1), and JK98. The phenotypes growth and survival rates of these populations were compared to confirm the feasibility for crossbreeding. The body length (BL), carapace length (CL), carapace width (CW), height of the second and third abdominal segment (HST), width of the second and third abdominal segment (WST), length of the first abdominal segment (LF), length of the last abdominal segment (LL), live body weight (BW), and survival rate were measured. Different combinations were statistically performed with ANOVA and Duncan's Multiple Range Test. The results show that the survival rate of JK98(a (TM) Euro)xWKN(a (TM),) was the highest, followed by WYP(a (TM) Euro)xWKN(a (TM),), FKN(a (TM) Euro)xWYP(a (TM),), FKN(a (TM) Euro)xHH1(a (TM),) and WYP(a (TM) Euro)xFKN(a (TM),); the body weight of FKN(a (TM) Euro)sxHH1(a (TM),) was the highest, followed by FKN(a (TM) Euro)xWYP(a (TM),), WYP(a (TM) Euro)xWKN(a (TM),), WYP(a (TM) Euro)xFKN(a (TM),) and JK98(a (TM) Euro)xWKN(a (TM),); the total length had the same ranking as the body weight. All growth traits in hybrids JK98(a (TM) Euro)xWKN(a (TM),) were the lowest among all combinations. F1 hybrids had significant difference (P < 0.05) in BL, CL, HST, LL, and BW; and insignificant difference (P > 0.05) in other growth traits and survival rate. The results of Duncan's Multiple Range Test are that BL and CL of JK98(a (TM) Euro)xWKN(a (TM),) were significantly different from the other combinations; HST different from the combination of FKN(a (TM) Euro)xWYP(a (TM),), FKN(a (TM) Euro)xHH1(a (TM),) and WYP(a (TM) Euro)xWKN(a (TM),); and BW different from FKN(a (TM) Euro)xWYP(a (TM),) and FKN(a (TM) Euro)xHH1(a (TM),). As a whole, the results indicate that the FKN(a (TM) Euro)xHH1(a (TM),) was the best combination in all growth traits. Therefore, hybridization can introduce the variation to base populations. The systematic selection program based on additive genetic performance may be more effective than crossbreeding.

Some new triazole derivatives as inhibitors for mild steel corrosion in acidic medium

Two triazole derivatives, 3,4-dichloro-acetophenone-O-1'-(1',3',4'-triazolyl)-methaneoxime (4-DTM) and 2,5-dichloro-acetophenone-O-1'-(1',3',4'-triazolyl)-methaneoxime (5-DTM) were synthesized, and the inhibition effects for mild steel in 1 M HCl solutions were investigated by weight loss measurements, electrochemical tests and scanning electronic microscopy (SEM). The weight loss measurements showed that these compounds have excellent inhibiting effect at a concentration of 1.0 x 10(-3) M. The potentiodynamic polarization experiment revealed that the triazole derivatives are inhibitors of mixed-type and electrochemical impedance spectroscopy (EIS) confirmed that changes in the impedance parameters (R-ct and C-dl) are due to surface adsorption. The inhibition efficiencies obtained from weight loss measurements and electrochemical tests were in good agreement. Adsorption followed the Langmuir isotherm with negative values of the free energy of adsorption Delta G(ads)(o). The thermodynamic parameters of adsorption were determined and are discussed. Results show that both 4-DTM and 5-DTM are good inhibitors for mild steel in acid media.

Synthesis and quantum-chemistry analysis on novel triazole compounds containing ester group

Nine novel triazole compounds containing ester group were designed and synthesized. Their structures were confirmed by elemental, H-1 NMR and IR analyses, and optimized by means of DFT (Density Functional Theory) method at the B3LYP/6-31G* level. Based on the quantum-chemical calculation results and the Pearson coefficients between FA and quantumchemical parameters, V, LogP, MR and E-HOMO are shown to be the important relative factors which affect FA of the title compounds.

Synthesis and QSAR studies of novel triazole compounds containing thioamide as potential antifungal agents

Eighteen novel triazole compounds containing thioamide were designed and synthesized. Their structures were confirmed by elemental analysis, H-1 NMR, IR, and MS. The title compounds exhibited certain antifungal activity. And the geometry structures of the title compounds were optimized by means of the density functional theory (DFT) method at B3LYP/6-31G* level. The quantitative structure-activity relationship (QSAR) of the title compounds was systematically investigated. A correlative equation between FA and DELH, V was well established by using the multiple linear regression (MLR). (c) 2006 Elsevier Ltd. All rights reserved.

Theoretical investigation on the adsorption of Ag+ and hydrated Ag+ cations on clean Si(111) surface

In this paper, the adsorption of Ag+ and hydrated Ag+ cations on clean Si(111) surface were investigated by using cluster (Gaussian 03) and periodic (DMol(3)) ab initio calculations. Si(111) surface was described with cluster models (Si14H17 and Si22H21) and a four-silicon layer slab with periodic boundary conditions. The effect of basis set superposition error (BSSE) was taken into account by applying the counterpoise correction. The calculated results indicated that the binding energies between hydrated Ag+ cations and clean Si(111) surface are large, suggesting a strong interaction between hydrated Ag+ cations and the semiconductor surface. With the increase of number, water molecules form hydrogen bond network with one another and only one water molecule binds directly to the Ag+ cation. The Ag+ cation in aqueous solution will safely attach to the clean Si(111) surface.

Detection of carbohydrates using new labeling reagent 1-(2-naphthyl)-3-methyl-5-pyrazolone by capillary zone electrophoresis with absorbance (UV)

A novel labeling reagent 1-(2-naphthyl)-3-methyl-5-pyrazolone (NMP) coupled with capillary electrophoresis (CE) with DAD detection for the determination of carbohydrates has been developed. The chromophore in the 1-phenyl-3-methyl-5-pyrazolone (PMP) reagent is replaced by naphthyl functional group, which results in a reagent with very high molar absorptivity (epsilon(251nm) = 5.58 x 10(4) L mol(-1) cm(-1)). This pen-nits NMP-labeled carbohydrates to be detected with UV absorbance in standard 50-mu m-i.d. fused silica capillaries by zone electrophoresis. in this mode, nanomolar concentrations of detection limits are obtained. The method for the derivatization. of carbohydrates with NMP is simplified. The derivatization reaction is rapid and mild in the presence of ammonia catalyst without further transfer steps. Nine monosaccharide derivatives such as mannose, galacturonic acid, glucuronic acid, rhamnose, glucose, galactose, xylose, arabinose and fucose can successfully be detected in CE mode. Good reproducibility can be obtained with relative standard deviation (R.S.D.) values of the migration times and peak area, respectively, from 0.44 to 0.48 and from 3.2 to 4.8. Furthermore, the developed method has been successfully applied to the analysis of carbohydrates in the hydrolyzed rape bee pollen samples. (C) 2008 Published by Elsevier B.V.

A new guaiane diterpenoid from Euphorbia wallichi

A new guaiane-type diterpenoid, (1 alpha, 5 alpha, 7 alpha)-3,10(18), 11-dictytriene-19-acid, was obtained from the roots of Euphorbia wallichii. This is the first isolation of guaiane diterpene from this genus of Euphorbia. The structure was elucidated by spectral methods. And the compound was tested for the cytotoxicities on the cancer cell line P-388 and A-549 in vitro.

东南沿海火山碎屑岩40Ar/39Ar年代学研究

The Mesozoic pyroclastic rocks cover a vast coastal area in southeastern China, which is an important part of volcanic belt around Pacific Ocean. However, the previous dates for these rocks are confused and conflicted with each other, which have limited the further researches. It is difficult to date pyroclastic rocks, for almost all the dating methods, due to the multiple sources during their formation. Single crystal laser probe 40Ar/39Ar method is a powerful means to date pyroclastic rocks with complex sources. By distinguishing the xenocrysts and altered materials, Singe crystal total fusions of CO2 lasing on the sanidine separates could yield rational 40Ar/39Ar results and distinguish their sources. Timing on formations of the Moshishan Group, after avoiding the exotic and altered grains by lasing on the single sanidine separate, was reported in this study. 40Ar/39Ar incremental heating results of Cement part of the pyroclastic rocks show that the age spectrums are too complex to interpret for geological significance because of the alteration and 39Ar recoil. Incremental heating on K-feldspar separate from pyroclastic rocks give reliable data. Combining 40Ar/39Ar incremental heating ages and laser total fusion ages, we suggest the age was 125Ma-120Ma for Dashuang Fm, 120-119 Ma for Gaowu Fm, 119-114Ma for Xishantou Fm, 114-112Ma for Chawan Fm and 112-110Ma for Jiuliping Fm. The most intense period of volcanic activity in eastern Zhejiang Province was at about 120Ma. These new ages are much younger than the previous ones, suggesting that these thick volcanic formations had been formed in very short durations.

地震反射界面形态与介质各向异性属性联立成像：地震反射波旅行时与偏振信息综合反演

It has been a difficult problem faced by seismologists for long time that how exactly to reconstruct the earth's geometric structure and distribution of physical attributes according to seismic wave's kinematical and dynamic characteristics, obtained in seismological observation. The jointing imaging of seismic reflector and anisotropy attributes in the earth interior is becoming the research hot spot. The limitation of shoot and observation system makes that the obtained seismic data are too scarce to exactly reconstruct the geological objects. It is popular that utilizing only seismic reflection traveltimes or polarizations information make inversion of the earth's velocity distribution by fixing seismic reflector configuration (vice versa), these will lead to the serious non-uniqueness reconstruction due to short of effective data, the non-uniqueness problem of reconstructing anisotropy attributes will be more serious than in isotropy media. Obviously it is not enough to restrict the media structure only by information of seismic reflection traveltimes or polarizations, which even sometimes will lead to distorted images and misinterpretation of subsurface structure. So we try to rebuild seismic reflection structure (geometry) and media anisotropic structure (physics) in the earth interior by jointing data of seismic wave kinematics and dynamics characteristics, we carry out the new experiment step by step, and the research mainly comprises of two parts: one is the reconstruction of P-wave vertical velocity and anisotropic structure(Thomsen parameter s and 8) in the transversely isotropic media with vertical symmetrical axis(VTI) by fixing geometrical structure, and the other is the simultaneous inversion of the reflector surface conformation and seismic anisotropic structure by jointing seismic reflection traveltimes and polarizations data. Simulated annealing method is used to the first research part, linear inversion based on BG theory and Simulated annealing are applied to the second one. All the research methods are checked by model experiments, then applied to the real data of the wide-angle seismic profile from Tunxi, Anhui Province, to Wenzhou, Zhejiang Province. The results are as following The inversion results based on jointing seismic PP-wave or PSV-wavereflection traveltimes and polarizations data are more close to real model than themodels based simply on one of the two data respectively. It is shown that the methodwe present here can effectively reconstruct the anisotropy attributes in the earth'sinterior when seismic reflector structure is fixed.The layer thickness, P-wave vertical velocity and Thomsen anisotropicparameters {s and 8) could be resolved simultaneously by jointing inversion ofseismic reflection traveltimes and polarizations with the linear inversion methodbased on BG theory.The image of the reflector structure, P-wave vertical velocity and theanisotropy parameters in the crust could be obtained from the wide-angle seismicprofile from Tunxi (in Anhui Province), to Wenzhou (in Zhejiang Province). Theresults reveal the difference of the reflector geometrical structure and physicalattributes in the crust between Yangtze block and Cathaysia block, and attempt tounderstand the characteristics of the crustal stress field in the areas.

酸沉降环境化学与硫同位素示踪研究──以浙江中部地区为例

研究区域降水样品pH值的分布范围为3.64-7.20，pH年均值为4.45。SO4、NO3、NH4、Ca、H是降水中主要的阴、阳离子。降水中SO4对降水酸度的贡献逐渐降低，而NO3的贡献则显著增加。SO4、NH4、Ca、H、NO3的沉降通量相对较大，其它离子则相对较小，同时降水离子成分沉降通量的季节变化非常明显。SO4和NO3、Ca和Mg以及Na和Cl表现出较好的相关关系，另外Ca和SO4、Mg和SO4以及Mg和NO3等酸、碱性离子之间也存在较好的相关性，但H与其它离子间并没有表现出明显的相关关系。降水中SO4、NH4、NO3和F主要来自人为活动的影响，Ca、k和Mg主要来自土壤、沙尘等地壳来源，Na、Cl属于典型的海盐性成分。 浙江中部地区大气降水硫同位素δ34S值的变化范围为+0.53‰－+14.23‰，平均值+5.04‰，区域内各地大气降水硫同位素组成基本一致。大气SO2的δ34S值变化范围在+0.95‰－+7.50‰之间，年均值为+4.73‰，气溶胶δ34S值变化范围则在+6.39‰－+9.83‰之间，年均值为+8.09‰。降水和大气SO2的δ34S值存在冬季高夏季低的季节性变化特征，同位素平衡分馏引起的温度效应和夏季生物成因硫的大量释放是造成季节性变化的主要控制因素。降水中人为来源硫的相对贡献约为53%－91%，年平均为73%，生物成因硫的相对贡献约为8%－44%，年平均为26%。远距离传输硫是研究区域降水中另一个非常重要的硫源，其相对贡献约为27%－44%。大气SO2氧化反应中多相氧化处于相对重要的地位，均相氧化在氧化反应机制中也有其不可低估的作用。研究区域大气环境的相对湿度对大气SO2的氧化机制有着重要的影响。

浙江省矾山明矾石矿床地球化学特征兼论中生代成矿体系

矾山明矾石矿床位于江山－绍兴深断裂南东侧，海西印支褶皱带的南东侧，中国板块东南构造区与太平洋板块的交接处，属于中国板块东南构造区。该矿床产在矾山破火山口内，是一个超大型明矾石矿床，同时矿床中的钒、镓含量也达到了综合利用的品位。该矿床研究程度低，缺少地球化学特征研究。因此，本次工作系统研究了该矿床常量元素、微量元素、稀土元素、硫和铅同位素地球化学特征。本次对明矾石矿床的研究获得以下几点初步认识： 1：成矿物质来源于火山岩。矿区火山岩中的K、Al、Na等矿石元素含量明显比其他地区高，并且从围岩→矿化围岩→矿石呈明显的富集趋势。稀土资料和铅同位素资料也都表明成矿物质来源于中生代火山岩。 2：V、Ga含量达到了综合利用的品位。微量元素资料表明，矿石中V平均含量为211.6ppm，Ga平均含量为16.78ppm，都大于地壳丰度，尤其是V远大于地壳丰度；同时发现，成矿时V以V¬5＋形式通过与Al3＋发生类质同像进入明矾石晶格，而矿石中Ga含量除与Al3＋外还与Fe3＋含量有关。 3：明矾石的稀土元素地球化学特征比较复杂。根据δEu值不同可分为三类： Eu弱负异常型，Eu弱正异常型和Eu强正异常型。影响稀土元素分布的因素主要为成矿原岩中富含碱性长石和成矿时的氧逸度和温度，另外矿石结构（如孔隙度）对稀土元素分布也有影响。研究表明，矿石稀土配分模式为轻稀土富集型，与火山岩基本一致。 4：硫同位素研究发现，黄铁矿的δ34S值为1.9～3.2‰，明矾石的δ34S值为13.62～16.02‰，后者明显大于前者。本次研究认为黄铁矿的δ34S值代表当时的岩浆源硫，而明矾石较大的δ34S值为岩浆硫经过同位素分馏的结果。铅同位素研究发现，明矾石矿石的206Pb/204Pb＝17.963～18.606，207Pb/204Pb＝15.439～15.672，208Pb/204Pb＝38.405～38.796。通过与中生代火山岩和基底变质岩的对比，本次研究认为明矾石的铅源为中生代火山岩来源，与基底变质岩并无直接的来源关系。 5：通过明矾石矿床的地球化学特征研究，结合实际地质特征和前人研究成果，本次研究提出了以下矿床成因：明矾石矿床形成环境为浅成低温氧化环境；成矿物质来源于围岩，成矿所需的硫源为分馏的岩浆硫；矿床形成时期为73～95Ma，比围岩晚10～20Ma；矿床成因为火山热液交代成因。 浙江省中生代火山岩成矿体系主要指受浙江省中生代火山构造、岩浆活动控制的一系列不同类型的矿床组合。成矿体系主要受江绍深断裂带和中生代陆相火山岩控制。前人对成矿体系中的单一矿床研究较多，但是缺少横向对比研究。本次工作主要通过对成矿体系中的两类矿床（金属矿床和非金属矿床）进行对比研究，结合中生代火山岩演化过程，初步探索成矿体系中各类矿床间的联系以及成矿体系与火山岩演变的关系。本次工作取得以下几点初步认识： 1：成矿体系中各类矿床的整体分布受江绍深断裂、温州－镇海大断裂等一些深大断裂控制。各矿床的具体控（容）矿构造都为次级压－压扭性断裂和破火山口构造，其中破火山口构造在成矿过程中占非常重要的作用。 2：成矿体系中各类矿床的成矿温度低，深度浅，为典型的浅成低温矿床。 3：铅同位素资料表明，矿床的铅源为中生代火山岩来源，与基底并无直接联系。氢氧同位素资料表明，各类矿床的成矿流体以中生代大气降水为主，岩浆水占很少部分或并无参与成矿。 4：成矿体系存在明显的成矿成岩时差，金属矿床在12.44～45.6Ma，萤石矿床为25～75Ma，其他非金属矿床为10～20Ma；铅锌（银）金等金属矿床为具有明显的两期成矿特征。

Perovskite-type B-site Bi-doped ceramic membranes for oxygen separation

Novel mixed conducting oxides, B-site Bi-doped perovskites were exploited and synthesized. Cubic perovskite structures were formed for BaBi0.2COyFe0.8-yO3-delta (y less than or equal to 0.4) and BaBixCo0.2Fe0.8-xP3-delta (x=0.1-0.5) The materials exhibited considerable high oxygen permeability at high temperature. The oxygen permeation flux of BaBi0.2Co0.35Fe0.45O3-delta membrane reached about 0.77 x 10(-6) mol/cm(2) s under an air/helium oxygen partial pressure gradient at 900 degrees C, which was much higher than that of other bismuth-contained mixed conducting membranes. The permeation fluxes of the materials increased with the increase of cobalt content, but no apparent simple relationship was found with the bismuth content. The materials also demonstrated excellent reversibility of oxygen adsorption and desorption. Stable time-related oxygen permeation fluxes were found for BaBi0.2CO0.35Fe0.45O3-delta and BaBi0.3Co0.2Fe0.5O3-delta a membranes at 875 degrees C.