Structure, luminescence and magnetic properties of AgLnW(2)O(8) (Ln = Eu, Gd, Tb and Dy) compounds

Four new compounds AgLnW(2)O(8) (Ln = Eu, Gd, Tb and Dy) are prepared by solid-state reactions. They crystallize with a scheelite-related monoclinic symmetry. Infrared (IR) spectra show complicated absorption transitions in the region of 1000-400 cm(-1) that are similar to those of AgLnMo(2)O(8). Broad excitation and emission bands of the tungstate group are observed in AgGdW2O8 and AgTbW2O8 with a large Stokes shift, 12 573 and 12 387 cm(-1), respectively. Excitation and emission spectra of AgLnW(2)O(8) (Ln = Eu, Gd and Tb) show that energy transfer from the tungstate to EU3+, Gd3+ and Tb3+ occurs and that Eu3+ ions occupy a single crystallographic site with the C-2 Site symmetry. (C) 1997 Elsevier Science Ltd. All rights reserved.

Synthesis, luminescence and intramolecular energy transfer of binary and ternary rare earth complexes with aromatic carboxylic acids and 1,10-phenanthroline

A series of binary and ternary rare earth complexes with para-substitued benzoic acids and 1,10-phenanthroline were synthesized. The phosphorescence spectra were measured and the lowest tripler state energies of ligands were determined, the phosphorescence lifetimes were obtained and intramolecular energy transfer mechanism between ligands was studied. The luminescence properties were also measured and were in agreement with the prediction. The energy match and intramolecular energy transfer process in these binary and ternary complexes were discussed in detail.

The crystal structure and supramolecular chain of [La(NO3)(3)(OH2)(2)(phen)]center dot 15-crown-5

[La(NO3)(3)(OH2)(2)(phen)]. 15-crown-5 is hexagonal, P6(5), with a = 10.955(2), c = 43.769(9) Angstrom, and D-calc = 1.668 g cm(-3) for Z = 6. In the complex, two nitrogen atoms (from phen) and eight oxygen atoms (six from three bidentate nitrate anions and two from water molecules) are coordinated to the central La(III) ion, forming a coordination polyhedron which is approximately a bicapped square antiprism. The coordinated water molecules donate hydrogen bonds to the oxygen atoms of the crown ether, forming polymeric hydrogen bonded chains which wrap helically along the unit cell direction c.

黄金矿的催化浸取

基于对金自溶解电化学过程的分析，提出此过程受阴极还原反应所控制，加入阴极反应催化剂，能加快金自溶解速度。实验结果充分表明：我们找到的催化剂Ａ能提高金的浸出速度和浸出效率。

STUDIES ON THE SYNTHETIC, STRUCTURAL, ELECTRICAL, AND MAGNETIC-PROPERTIES OF THE NEW LAYERED OXIDES LN(2)MCO(2)O(7) (LN=SM, GD, M=SR, BA)

Three new oxides Ln(2)MCo(2)O(7) (Ln = Sm, Gd; M = Sr, Ba) have been synthesized in solid state reaction method. The powder X-ray diffraction spectra show that they are all isostructural with Sr3Ti2O7. The electrical resistivities in the temperature range 300-1100 K show that they are all semiconductors, and a transition to metals is observed at 1053, 1053, and 573 K for Sm2SrCo2O7, Gd2SrCo2O7, and Sm2BaCo2O7, respectively. The magnetic suspectivities of Gd2SrCo2O7 in the temperature range 300-673 K fit the Curie-Weiss law well. A plateau is observed in the curves of Sm(2)MCo(2)O(7) (M = Sr, Ba) which is attributed to the configuration state change of Co(III) from low spin to high spin. (C) 1995 Academic Press, Inc.

对-(二甲氨基)苯基锗倍半氧化物的合成、结构及其对体外培养癌细胞的作用

在常压下,由N,N′-二甲基苯胺和GeCl_4合成了对-(二甲氨基)苯基锗倍半氧化物,研究了它的红外光谱、光电子能谱及热分析性质,讨论了化合物的结构.用体外细胞培养法,观察了它对人乳腺癌细胞分裂的抑制作用。

SYNTHESIS AND CHARACTERIZATION OF HIGH-PERFORMANCE PA FILM

I. INTRODUCTIONIn last decade, considerable attention was focused on polyacetylene. However, its practical application was affected considerably because of its poor strength and stability. Recently, Narrmann et al. reported that they could synthesize PA film with improved properties using modified Ziegler-Natta catalyst. However, no detailed

3~C-NMR 研究糠醇和糠醇与三■2—羟乙基■异氰尿酸酯缩聚磺化反应

80年代初,Kurihara 等开发的 PEC—1000复合膜,首次实现了工业规模的海水一级淡化,并在无机和有机水溶液的分离和浓缩方面显示了巨大潜力。据分析这种高效分离膜的功能分离层的主要结构成分是糠醇(FA)和三(?)2一羟乙基(?)异氰尿酸酯(THEIC)

Vertical distribution of bacterial and archaeal communities along discrete layers of a deep-sea cold sediment sample at the East Pacific Rise (similar to 13 degrees N)

The community structure and vertical distribution of prokaryotes in a deep-sea (ca. 3,191 m) cold sediment sample (ca. 43 cm long) collected at the East Pacific Rise (EPR) similar to 13 degrees N were studied with 16SrDNA-based molecular analyses. Total community DNA was extracted from each of four discrete layers EPRDS-1, -2, -3 and -4 (from top to bottom) and 16S rDNA were amplified by PCR. Cluster analysis of DGGE profiles revealed that the bacterial communities shifted sharply between EPRDS-1 and EPRDS-2 in similarity coefficient at merely 49%. Twenty-three sequences retrieved from DGGE bands fell into 11 groups based on BLAST and bootstrap analysis. The dominant groups in the bacterial communities were Chloroflexi, Gamma proteobacteria, Actinobacterium and unidentified bacteria, with their corresponding percentages varying along discrete layers. Pairwise Fst (F-statistics) values between the archaeal clone libraries indicated that the archaeal communities changed distinctly between EPRDS-2 and EPRDS-3. Sequences from the archaeal libraries were divided to eight groups. Crenarchaea Marine Group I (MGI) was prevalent in EPRDS-1 at 83%, while Uncultured Crenarchaea group II B (UCII B) abounded in EPRDS-4 at 61%. Our results revealed that the vertically stratified distribution of prokaryotic communities might be in response to the geochemical settings and suggested that the sampling area was influenced by hydrothermalism. The copresence of members related to hydrothermalism and cold deep-sea environments in the microbial community indicated that the area might be a transitional region from hydrothermal vents to cold deep-sea sediments.

海洋沉积物中磷化氢的分布、释放与转化研究

磷化氢（PH3）是磷循环的气相载体，以气体自由态和基质结合态（MBP）两种形式存在于环境中。自然环境中磷化氢的发现是对磷生物地球化学循环的重要补充，它在磷循环中的地位和作用及产生机制开始成为人们关注的热点。目前国内外在湖泊、陆地土壤及大气中已开展了较为广泛的研究，但是关于海洋中的研究还较少。开展磷化氢在海洋沉积物中的分布特征，及其释放通量、与其它磷形态的转化、对微藻生长的影响等行为研究对弄清海洋环境中磷化氢的迁移转化机制及其在磷循环中的作用和地位具有重要的科学意义。 本论文以不同环境条件下的海洋沉积物为研究对象，采用野外实验与室内模拟相结合的方法，运用改进的柱前二次低温冷阱富集和气相色谱-氮磷检测器联用技术等分析手段，系统研究了海洋沉积物中磷化氢的分布特征、环境因子对其分布的影响、沉积物磷化氢向水体、大气中的释放、迁移、转化规律；初步了解了海洋沉积物中结合态磷化氢的分布特征及其释放通量；揭示了磷化氢对海洋环境的可能影响。主要研究结果如下： MBP广泛存在于海洋沉积物中。中国沿海表层沉积物中MBP的浓度范围为：0.89-25.86 ng/kg, dry，其分布也表现出一定的空间分布特征，在同一离岸断面上，有近岸浓度高，远岸浓度低的分布规律；在北黄海、南黄海、东海北部海域、东海南部海域和南海海域的平均浓度分别为：5.57±3.78、3.78±2.81、5.27±3.07、5.48±4.05 和 13.52±7.86 ng/kg dry，与其它海域相比，南海海域的MBP浓度要相对较高一些。长江口海域表层沉积物中MBP的浓度范围为：1.93-94.86 ng/kg, dry。其分布也表现出一定的空间和季节分布特征。上游河口沉积物中MBP的浓度要普遍高于下游河口，平均浓度分别为31.34和4.79 ng/kg, dry。靠近石洞口、竹园排污口以及黄浦江口的S3和S4站位处MBP的浓度要显著高于其它站位，季节平均浓度分别为43.01和61.54 ng/kg, dry。MBP浓度的季节差异并不显著，上游河口和下游河口MBP浓度表现出相似的季节变化特征，一般来说8月和11月要稍高于2月和5月。澳大利亚伊拉瓦拉海湾柱状沉积物中的MBP表现出一定的垂直分布特征。两个柱状沉积物样品均在中下层存在MBP的高值区，且该海湾MBP的含量要远高于中国近海及长江口海域MBP的含量，两个柱状沉积物中MBP的平均浓度分别为637.3和542.6 ng/kg, dry。 环境因子与MBP含量关系的研究结果表明：较高的TP、OP、IP、OC、TN含量均有利于高浓度MBP的产生；TP、OP、OC与MBP含量之间存在着较强的线性相关关系，是控制MBP分布的主要因素；氧化还原电位与MBP含量存在着显著的线性负相关，说明还原环境更有利于沉积物中高浓度MBP的存在；平均粒径与MBP含量存在着一定的线性负相关，说明小粒径有利于高浓度MBP的存在；水深、上升流引起的扰动等也是影响MBP分布的可能原因。并且，在本论文对中国沿海沉积物、长江口沉积物和澳大利亚海湾沉积物的研究中，均得到了MBP含量与OP存在着强烈的线性相关关系，而与IP的线性相关关系较弱或不相关的结论，说明海洋沉积物中的MBP更可能来源于微生物对有机磷成分的降解。另外，长江口海域沉积物中MBP含量与上层海水中活性磷酸盐、总磷、叶绿素a的含量也存在着一定的线性相关关系，说明沉积物中磷化氢的释放可能会对上层水环境产生影响。 静态箱法释放通量的研究结果显示，胶州湾海域沉积物存在着磷化氢的释放现象。沉积物-大气界面和水-大气界面磷化氢的释放通量分别为：27.77和17.37 ng/(m2•h)，该结果要高于Louisiana湿地、水稻田和太湖水体磷化氢的排放通量。并据此估算出胶州湾的磷化氢年排放量为75.75kg/y，高于太湖及比利时垃圾填埋场的磷化氢年排放量。不同底质沉积物释放磷化氢的顺序为：虾池沉积物>滩涂沉积物>海滩黑泥沉积物>海滩排污口旁的砂质泥；践踏能显著促进磷化氢的释放。磷化氢的释放通量与沉积物中MBP的含量有显著的线性相关关系；胶州湾养殖池、滩涂沉积物及海域水体是大气中磷化氢的重要来源，沉积物中的磷化氢可连续向上层水体或大气中释放。晴天，胶州湾近海海域空气中磷化氢的浓度范围为1.06-16.90 ng/m3，且表现出早上和傍晚高，中午时分相对较低的变化规律；空气中磷化氢的浓度与光照强度及释放源释放量的大小有关。 利用室内模拟方法，研究了磷化氢在海水中的转化过程及其对海洋微藻生长的影响，并得出了一些初步结论。日光灯照射条件下，通入海水中的磷化氢可部分转化为磷酸盐和总磷，并且转化后主要以磷酸盐的形式存在。环境条件会对该转化过程产生影响，避光条件下，磷化氢的转化率较低，日光灯照射和紫外灯照射均能促进该转化过程，特别是紫外灯照射，促进效果显著；添加氧气或三价铁离子氧化剂也能促进该转化过程。微藻生长实验结果表明，适量磷化氢气体的通入，能显著刺激并促进磷限制条件下东海原甲藻和赤潮异弯藻的生长，但这种刺激作用并不是无限制的，后期刺激生长作用会变弱或停止生长；低量磷化氢气体的通入，刺激作用不明显；高量磷化氢气体的通入，则会抑制两种海洋微藻的生长。东海原甲藻和赤潮异弯藻对通入磷化氢的响应略有差异，后者对磷化氢的反应更为灵敏； 次磷酸盐和亚磷酸盐也都能刺激两种海洋微藻的生长，但与磷化氢相比，其影响作用相对较小。 本论文的初步研究结果表明，在磷的海洋生物地球化学循环中，需要考虑磷化氢的作用，其长期、连续的释放对磷循环的贡献不可忽视，并可能是磷限制海域赤潮形成的补充机制。

Cloning and expression analysis of a HSP70 gene from Pacific abalone (Haliotis discus hannai)

Heat shock protein 70 (HSP70), the primary member of HSPs that are responsive of thermal stress, is found in all multicellular organisms and functions mostly as molecular chaperon. The inducible HSP70 cDNA cloned from Pacific abalone (Haliotis discus hannai) using rapid amplification of cDNA ends (RACE), was highly homologous to other HSP70 genes. The full-length cDNA of the Pacific abalone HSP70 was 2631 bp, consisting of a 5'-terminal untranslated region (UTR) of 90 bp, a 3'-terminal UTR of 573 by with a canonical polyadenylation signal sequence AATAAA and a poly (A) tail, and an open reading frame of 1968 bp. The HSP70 cDNA encoded a polypeptide of 655 amino acids with an ATPase domain of 382 amino acids, the substrate peptide binding domain of 161 amino acids and a C-terminus domain of 112 amino acids. The temporal expression of HSP70 was measured by semi-quantitative RT-PCR after heat shock and bacterial challenge. Challenge of Pacific abalone with heat shock or the pathogenic bacteria Vibrio anguillarum resulted in a dramatic increase in the expression of HSP70 mRNA level in muscle, followed by a recovery to normal level after 96 h. Unlike the muscle, the levels of HSP70 expression in gills reached the top at 12 h and maintained a relatively high level compared with the control after thermal and bacterial challenge. The upregulated mRNA expression of HSP70 in the abalone following heat shock and infection response indicates that the HSP70 gene is inducible and involved in immune response. (c) 2006 Elsevier Ltd. All rights reserved.

Copper complexation by fulvic acid affects copper toxicity to the larvae of the polychaete Hydroides elegans

Copper toxicity is influenced by a variety of environmental factors including dissolved organic matter (DOM). We examined the complexation of copper by fulvic acid (FA), one of the major components of DOM, by measuring the decline in labile copper by anodic stripping voltammetrically (ASV). The data were described using a one-site ligand binding model, with a ligand concentration of 0.19 mu mol site mg(-1) C, and a logK' of 6.2. The model was used to predict labile copper concentration in a bioassay designed to quantify the extent to which Cu-FA complexation affected copper toxicity to the larvae of marine polychaete Hydroides elegans. The toxicity data, when expressed as labile copper concentration causing abnormal development, were independent of FA concentration and could be modeled as a logistic function, with a 48-h EC50 of 58.9 mu g 1(-1). However, when the data were expressed as a function of total copper concentration, the toxicity was dependent on FA concentration, with a 48-h EC50 ranging from 55.6 mu g 1(-1) in the no-FA control to 137.4 mu g 1(-1) in the 20 mg 1(-1) FA treatment. Thus, FA was protective against copper toxicity to the larvae, and such an effect was caused by the reduction in labile copper due to Cu-FA complexation. Our results demonstrate the potential of ASV as a useful tool for predicting metal toxicity to the larvae in coastal environment where DOM plays an important role in complexing metal ions. (c) 2007 Elsevier Ltd. All rights reserved.

Electrochemical and thermodynamic investigation of diniconazole and triadimefon as corrosion inhibitors for copper in synthetic seawater

This paper presents the investigation of diniconzole and triadimefon as chemical corrosion inhibitors for freshly polished copper in synthetic seawater (3.5% NaCl solution). Determination of weight loss, polarization curves, electrochemical impedance spectroscopy (EIS), and SEM, were performed to analyze the inhibiting performance of these compounds. Polarization curves show that they act as mixed-type inhibitors. EIS indicates that an adsorption film of the inhibitors is formed on copper surface. The highest values of inhibition efficiency are respectively, 99.2% and 97.3% at 100 mg/L concentration. Thermodynamic calculation suggests that chemisorptions between the compounds and copper are accordance with Langmuir adsorption isotherm. (C) 2010 Elsevier Ltd. All rights reserved.

高山植物条纹狭蕊龙胆的分子亲缘地理学研究

草本植物由于较短的生活周期以及对环境变化的敏感性,可能会更好地揭示第四纪冰期以来植物居群变化的历史过程。分子亲缘地理学研究是揭示动植物居群历史的有力工具,但到目前为止对青藏高原草本植物的分子亲缘地理学研究几乎是空白。因此,本文选择在青藏高原及邻近地区生长的一年生高山草本植物条纹狭蕊龙胆为研究对象,进行了13个居群155个个体的叶绿体基因组（cpDNA）非编码片段trnH（GUG）-psbA基因间区序列变异检测,共发现7种单倍型,其中单倍型Hap A是分布最广的,而单倍型Hap E、Hap F和Hap G是拥有的居群所特有的。青藏高原东北部、东部及邻近地区的每个居群拥有的单倍型非常单一,而高原东南部横断山区的单倍型分布很集中,遗传多样性也相对较高。分子变异分析（AMOVA）结果表明整个分布区条纹狭蕊龙胆的遗传变异主要存在于居群间（73.05%）,且居群间的遗传分化很高（G_(ST)=0.805,F_(ST)=0.731,N_(ST)=0.859）,有着显著的亲缘地理学结构（N_(ST)〉G_(ST),P〈0.05）和较低的居群间的平均基因流（N_m=0.184）。结合巢式支系法分析（NCA）,根据本文的研究结果推测青藏高原东南部横断山区是该植物第四纪冰期时可能的避难所,而且在间冰期或冰期后,伴随着异域片段化和过去片段化从避难所发生范围扩张而形成当前单倍型及居群的分布格局。

柴达木盆地唐古特白刺籽油保护肝损伤作用研究

对柴达木盆地唐古特白刺种籽油保护化学性肝损伤作用进行了研究.将小鼠按体重随机分为白刺籽油高、中、低剂量组,另设空白对照组和联苯双酯、藏茵陈阳性对照组.小鼠连续灌胃给药15 d后,用CCl4进行肝损伤,测定小鼠血清谷丙转氨酶(ALT)、谷草转氨酶(AST);肝脏过氧化脂质(LPO)降解产物丙二醛(MDA)和谷胱甘肽过氧化物酶(GSH-Px)的含量.结果显示,白刺籽油对血清ALT、AST具有显著的抑制作用,显著拮抗肝脏MDA的升高,显著提高肝脏GSH-Px含量.表明白刺籽油具有明显的保护化学性肝损伤的保健作用.