The behaviors and sources of dissolved arsenic and antimony in Bohai Bay

In this paper, we determined the concentrations of antimony species (antimonite (Sb(III)), antimonate (Sb(V)) and dissolved inorganic antimony (DISb)) and arsenic, in Bohai Bay seawaters, as well as the relationships of the analytes with environmental factors such as seawater characteristics (e.g., suspended particulate material (SPM), salinity and total organic carbon (TOC)), heavy metals, nutrients and phytoplankton species, and evaluated the sources of arsenic and antimony. Dissolved arsenic and antimony concentrations in the surface waters were ranging spatially from 1.03 to 1.26 ng/ml and 0.386 to 1.075 ng/ml, with mean values of 1.18 and 0.562 ng/ml, respectively. Sb(V) as the prominent chemical species constituted about 89%. Regarding arsenic concentrations in the surface waters, there was a tendency for a small variation. However, antimony species concentrations were much variable than arsenic. The highest arsenic and antimony concentrations were found near the Haihe Estuary. These distribution patterns were controlled mainly by environmental factors, biological activities and sources. In this region, DISb and Sb(V) negatively correlated with salinity. Besides, arsenic and antimony correlated well with the nutrients, chlorophyll a and phytoplankton, implying that arsenic and antimony had been involved in biological cycling. In addition, according to our estimate, about 333.5 x 10(8) mg/year of arsenic and 454.2 x 10(8) mg/year of antimony reached Bohai Bay via rivers. (C) 2010 Elsevier Ltd. All rights reserved.

Corrosion inhibition of mild steel in acidic solution by some oxo-triazole derivatives

The oxo-triazole derivative (DTP) was synthesized and its inhibiting action on the corrosion of mild steel in sulphuric acid was investigated by means of weight loss, potentiodynamic polarization, EIS and SEM. The results revealed that DTP was an excellent inhibitor and the inhibition efficiencies obtained from weight loss experiment and electrochemical experiment were in good agreement. Potentiodynamic polarization studies clearly revealed that DTP acted essentially as the mixed-type inhibitor. Thermodynamic and kinetic parameters were obtained from weight loss of the different experimental temperatures, which suggested that at different temperatures (298-333 K) the adsorption of DTP on metal surface obeyed Langmuir adsorption isotherm model. (C) 2009 Elsevier Ltd. All rights reserved.

Relationship between the ennoblement of passive metals and microbe adsorption kinetics in seawater

The relationship between microbial colonization of two kinds of passive metals and ennobling of their corrosion potentials (E-corr) were studied. Two types of passive metal coupons were exposed to natural seawater for about ten days. Under laboratory conditions, all corrosion potentials of the samples ennobled for about 200 mV. Epifluorescence microscopy showed that bacteria adsorption was the main process during about the first day immersion and bacteria reproduced in the following days. The bacteria number increased on the metal surface according to an exponential law and the kinetics of bacteria adsorption at the metal surface during this period was proposed. The ennoblement of E-corr was similar to the increasing bacteria number: E-corr increased quickly during the bacteria adsorption process and increased slowly after biofilms had formed.

大鼠端脑中神经递质的荧光衍生化高效液相色谱质谱联用法研究

以1,2-苯并-3,4-二氢咔唑-9-乙基氯甲酸酯(BCEOC)作为柱前荧光衍生试剂,在Hypersil BDS C_(18)(4.6 mm×100 mm,5 μm)反相色谱柱上,荧光检测波长为390 nm(激发波长为333 nm)下,采用梯度洗脱实现了5种神经递质标准品(谷氨酸、γ-氨基丁酸、多巴胺、5-羟色胺、5-羟吲哚乙酸)衍生物的同时分离检测.5种组分的线性范围为24 fmol～200 pmol,线性回归系数均大于0.9997;检出限为4.0～12.6 fmol(S/N=3∶1).在柱后在线质谱电喷雾电离源(ESI Source)正离子模式下实现了各组分的快速质谱鉴定,对其二级质谱裂解碎片峰进行了归属,并以5-羟色胺衍生物为例进行了质谱裂解机理解析.对A、B两组(A:安静对照组,B:运动训练组)4种取样状态(安静、运动1 h、力竭即刻、力竭后恢复12 h)下的64只大鼠端脑组织中5种神经递质的定量测定结果表明,长期中等强度的运动训练能够有效提高大鼠的运动能力及耐力运动后疲劳恢复能力.方法的灵敏度高、重现性好,为大鼠端脑中氨基酸类和单胺类神经递质的同时测定建立了一种新方法.

HPLC-APCI-MS法分析测定白刺籽油中游离脂肪酸

利用荧光衍生试剂1,2-苯并-3,4-二氢咔唑-9-乙基对甲苯磺酸酯(BDETS)作为脂肪酸柱前衍生化试剂,采用梯度洗脱在Eclipse XDB-C_8色谱柱上对游离脂肪酸(FFA)(油酸、亚油酸、软脂酸和硬脂酸)衍生物进行分离.利用柱后在线的串联质谱以大气压化学电离源(APCI)正离子模式实现了各组分的质谱定性.荧光检测的激发和发射波长分别为λ_(ex)=333 nm,λ_(em)=390 nm.脂肪酸的线性回归系数大于0.9990,检出限为3.38～6.59 nmol/L.建立的方法具有良好的重现性.利用此方法对超临界CO_2提取的唐古特白刺籽油中几种游离脂肪酸进行了分析.结果表明白刺籽油中含有大量的游离不饱和脂肪酸.

大鼠血浆中痕量氨基酸的柱前衍生-高效液相色谱串联质谱测定

以1,2-苯并-3,4-二氢咔唑-9-乙基氯甲酸酯(BCEOC)作为柱前荧光衍生试剂,在Hypersil BDS C18 (4.6 ×200 mm, 5 μm)反相色谱柱上,荧光检测波长为390 nm(激发波长为333 nm),采用梯度洗脱实现了20种氨基酸标准品衍生物的分离检测.20种组分的线性范围为51.6 fmol～105.6 pmol,线性回归系数均大于0.9995;检出限为6.3～177.6 fmol (S/N=3:1).经柱后串联质谱电喷雾电离源(ESI Source)实现了各组分的质谱鉴定,并以酪氨酸(Tyr)衍生物为例进行了质谱裂解机理解析.对A、B、C三组(A:安静对照组;B:运动力竭即刻组;C:力竭恢复12 h 组) 24只大鼠血浆中氨基酸的定量测定结果表明,运动力竭即刻较安静状态大鼠血浆氨基酸含量明显增加;力竭恢复12 h 后血浆氨基酸水平基本恢复到运动前状态.方法的灵敏度高、重现性好,为大鼠血浆中氨基酸的测定提供了一种新方法

鼠类粪便中类固醇的荧光标记及质谱鉴定

利用新型荧光试剂1,2-苯并-3,4-二氢咔唑-9-乙基肼基甲酸酯(BCEC)作柱前衍生化试剂, 在Hypersil BDS C_(18) (4.6 mm * 200 mm, 5 μm) 色谱柱上，采用梯度洗脱对皮质醇、皮质酮、睾酮、孕酮4种类固醇荧光衍生物进行了优化分离。65℃下在乙腈溶剂中以三氯乙酸作催化剂,衍生反应2 h后获得稳定的荧光产物。激发和发射波长分别为333 nm和390 nm。采用大气压化学电离源(APCI)正离子模式, 实现了黑线姬鼠粪便中４种类固醇化合物的定性及定量测定。线性回归系数均在0.9999以上,检出限为47.3～71.2 fmol。

藏药牛尾蒿油滴丸含量测定的气相色谱方法学研究

目的：建立测定牛尾蒿油滴丸中β-蒎烯含量的方法。方法：气相色谱法，采用填充色谱柱（3m×3mm），固定相为8％二乙二醇丁二酸酯，汽化温度180℃，柱温120℃，载气（氮气）流速10mL•min^-1。结果：β-蒎烯的理论塔板数为2106，回归方程为Y=2．705×10^5X-3．544×10^3（r=0．9999），线性范围为0．2163—3．460mg•mL^-1，平均回收率±RSD为99．16％±0．59％。结论：以该法测定主要有效成分β-蒎烯的含量，理论塔板数较高、分离度较好。该方法可用于牛尾蒿油滴丸的质量控制。

高原鼠兔领域行为时间分配格局及其对风险环境适应的探讨

采用直接观察法测定了高原鼠兔地面、洞道活动时间及进、出洞频率.结果表明,在07:00～18:00,雄性和雌性高原鼠兔平均地面活动时间分别占总活动时间比例的87.09%和85.22%.地面活动时间具有明显的季节性,但两性个体间无显著的差异.繁殖早期,成年雌体地面活动时间显著高于繁殖后期,第2胎幼体地面活动时间显著低于第1胎幼体.不同年龄和性别的高原鼠兔进洞频率存在极显著差异,5月成年雌体进洞频率最高,而成年雄体在4月进洞频率最低.研究结果验证了捕食风险可制约鼠兔属动物领域活动时间分配,高风险环境能增加其利用洞道的时间及频率的特定假设.

昼夜温差对小麦生长特性的影响

在严格控制光照(350μmol photons m -2s-1)和空气相对湿度(75％)的人工气候室内,模拟青海高原昼夜温差较大的环境条件(25℃/10℃,昼/夜),以无昼夜温差的环境条件(25℃/25℃,昼/夜)为对照,对不同环境条件下选育的青海高原338和上海沪麦5号小麦品种的生长发育及经济性状的形成进行了比较研究。结果表明,15℃昼夜温差处理较对照条件下生长的小麦表现较好,总叶面积增加,生育期和叶片寿命延长,植株总干重和每穗粒数及千粒重均显著高于无昼夜温差条件下生长的小麦。因此,较大的昼夜温差环境条件是青海高原小麦易于高产的重要原因。 从品种看,青海的高原338在15℃昼夜温差处理下生长表现显著优于上海的沪 麦5号。而在无昼夜温差条件下，两个品种的生长情况正好相反。由此可以看出，培育适合当地昼夜温差环境因素的品种也是小麦获得高产的主要因素。

AUV系统辨识与广义预测控制研究

本论文的研究内容分为两方面：AUV的建模和控制。 建模方面，主要对当前用于AUV的建模方法进行了分类及对比，给出了水动力机理建模、水动力辨识、面向目标的系统辨识三类方法的优缺点。 根据可辨识性理论，对AUV闭环系统进行分析，给出了AUV闭环系统可辨识的充分条件。为了提高辨识算法的实时性，解决辨识过程中的“数据饱和”问题，给出了改进的变步长增广卡尔曼滤波辨识算法。利用小型AUV湖上试验数据辨识出航向回路、深度回路的系统模型，通过不同的试验数据与模型预测值的相关性验证模型，试验结果表明了该算法应用于AUV闭环系统建模的可行性。 控制方面，在传统PID控制、S面控制方法基础上，借鉴单神经元PID控制思想，将积分环节加入S面控制中来简化S面PID控制算法，并通过仿真验证了算法的可行性。上述方法参数调节依赖工程经验，而广义预测控制具有对模型要求低、算法鲁棒性强、参数调节简单等优点。因此，本文对输入输出约束的广义预测控制快速算法应用于AUV系统进行仿真，通过小型AUV水池试验验证了算法的有效性。

初论特提斯构造域一些大型-超大型金属矿床集中区聚矿构造

特提斯构造域是目前世界关注和研究的地学前沿科学问题之一。I．Metcalfe从构造演化角度将其划分为古特提斯、中特提斯及新特提斯，代表了从古生代特斯洋三次打开与闭合的构造过程。从聚矿构造类型看，一些大型-超大型金属矿床不但与其构造域中的大陆边缘的张裂-伸展变形过程有密切关系。而且与其打开的同时，澳大利亚陆块内前泥盆纪大洋盆地的闭合及造山运动有关。

地史早期岩石中的铅锌演化--狼山-渣尔泰山中元古代铅锌成矿的物质基础

以中国内蒙古狼山一渣尔泰山中元古代SEDEX型铅．锌成矿带为例，研究了该区从太古代到中元古代地壳岩石的铅锌含量和变化关系以及与成矿的关系。研究发现，从早到晚，岩石SiO2和K2O含量升高，铅含量也与二者同步增加；FeO、MgO、CaO及Na20含量呈下降趋势，锌含量也同步降低。在太古代时，岩石的Zn／Pb比值一般〉8，中元古代时这一比值降低为2～4。矿石的Zn／Pb比值与基底岩石Zn／Pb比值具有很好的一致性。铅锌这种随时间的变化与中元古代铅的暴发性成矿及大规模铅锌共生矿床的形成是同步的，说明基底岩石中的铅和锌是该成矿带SEDEX矿床成矿的物质基础.

Characterization and thermodynamic study of ultra-fine particle of Ni-B amorphous alloy

Ultra-fine particle of Ni-B amorphous alloy was prepared by chemical reduction of Ni2+ with NaBH4 and characterized with TEM and XRD. The heat capacity and thermal stability were measured with a high-precision automatic adiabatic calorimeter and DTA. The upper limit of applied temperature of the substance was found to be 684 K for use as catalyst. (C) 1999 Elsevier Science B.V. All rights reserved.