一些含锗有机酸的快原子轰击质谱

本文报道了—系列合锗有机酸在甘油中的快原子轰击质谱(FABMS)及其在间硝基苄醇(NBA)中的正、负离子FABMS.这些含锗有机酸在不同的底物中的FABMS显示了不同的特征.负离子谱提供了分子量信息,正、负离子谱可为这类化合物的结构鉴定提供互相补充的信息.讨论了底物和取代基对FABMS的影响,正、负离子的产生机制及离子的亚稳分解途径.

STATISTICAL THERMODYNAMICS IN THE FRAMEWORK OF THE LATTICE FLUID MODEL .1. POLYDISPERSE POLYMERS OF SPECIAL DISTRIBUTION

The Gibbs free energies and equations of state of polymers with special molar mass distributions, e.g., Flory distribution, uniform distribution and Schulz distribution, are derived based on a lattice fluid model. The influence of the polydispersity (or t

MAGNETIC-PROPERTIES OF LANTHANUM MANGANITE AND VALENCE EQUILIBRIA OF MANGANESE

The paramagnetic susceptibility of lanthanum manganite has been measured over a wide temperature range (100-1073 K). On the basis of the thermodynamic equilibria between the various manganese ions with different valence and spin states and the magnetic interactions between the various manganese ions, a semiempirical formula has been proposed to calculate the paramagnetic susceptibilities of lanthanum manganite at different temperatures. The results indicate that most of the discrepancies between the calculated and experimental reciprocal susceptibilities of lanthanum manganite are less than 10% and that the relative contents of the various manganese ions in lanthanum manganite vary with temperature. The relative content of the trivalent manganese ion with a high spin state is dominant over the whole temperature range, while be relative content of the tetravalent manganese ion with a high spin state decreases monotonously with increasing temperature. At 300 K the calculated relative content of the tetravalent manganese ion in lanthanum manganite is about 34%, which is in good agreement with the experimental result (30%). There are some divalent manganese ions present in lanthanum manganite from low temperature to high temperature. The ratio of the relative contents of the tetravalent and divalent manganese ions in the compound varies with temperature. Above 750 K the relative content of the tetravalent manganese ion is less than that of the divalent manganese ion. The variation in the electrical resistivity of lanthanum manganite with temperature has also been interpreted reasonably.

AMPEROMETRIC FLOW-INJECTION ANALYSIS OF HYDRAZINE BY ELECTROCATALYTIC OXIDATION AT COBALT TETRAPHENYLPORPHYRIN MODIFIED ELECTRODE WITH HEAT-TREATMENT

Chemically modified electrodes prepared by treating the cobalt tetraphenylporphyrin modified glassy-carbon electrode at 750-degrees (HCME) are shown to catalyze the electrooxidation of hydrazine. The oxidation occurred at +0.63 V vs. Ag/AgCl (saturated potassium chloride) in pH 2.5 media. The catalytic response is evaluated with respect to solution pH, potential scan-rate, concentration dependence and flow-rate. The catalytic stability of the HCME is compared with that of the cobalt tetraphenylporphyrin adsorbed glassy-carbon electrode. The stability of the HCME was excellent in acidic solution and even in solutions containing organic solvent (50% CH3OH). When used as the sensing electrode in amperometric detection in flow-injection analysis, the HCME permitted sensitive detection of hydrazine at 0.5 V. The limit of detection was 0.1 ng. The linear range was from 50 ng to 2.4-mu-g. The method is very sensitive and selective.

[Li(THF)_4][GdCl_4(THF)_2]的晶体结构

氯化钆与对-甲基苯基锂在四氢呋喃中反应得到产物之一为[Li(THF)_4][GdCl_4-(THF)_2],(M_r=738.2),在-70℃下进行X-射线衍射研究。其晶体属单斜晶系,P2/n空间群。晶体学参数为a=13.263(2),b=8.474(1),c=14.961(0);β=99.72(1)°,V=1657.23(?)~3,Z=2,D_c=1.48g/cm~3,F(000)=750,μ_c=24.2cm~(-1),最终偏离子为R=0.0614。研究结果表明,本题晶体是离子型晶体,围绕Gd~(3+)的四个Cl~-离子和两个THF分子的氧原子构成畸变的八面体。Li~+周围的四个THF分子的氧原子构成一个近似的四面体。

热处理四苯基钴卟啉修饰玻碳电极电催化氧化肼及其流动注射检测

肼是较难氧化的物质,在酸性溶液中,在碳电极上电化学检测要求检测电位正于1.0V.用董绍俊等报道的方法,我们在750℃下对四苯基钴卟啉修饰玻碳电极热处理1h,制得修饰电极(简称HCME).首次发现这种HCME在酸性溶液中对肼具有良好的电催化氧化作用和极高的催化稳定性. 循环伏安实验发现,在pH2.5的磷酸缓

Expressed sequence tags from the zhikong scallop (Chlamys farreri): Discovery and annotation of host-defense genes

A high-quality cDNA library was constructed from whole body tissues of the zhikong scallop, Chlamys farreri, challenged by Listonella anguillarum. A total of 5720 clones were sequenced, yielding 5123 expressed sequence tags (ESTs). Among the 3326 unique genes identified, 2289 (69%) genes had no significant (E-value < 1e-5) matches to known sequences in public databases and 194 (6%) matched proteins of unknown functions. The remaining 843 (25%) genes that exhibited homology with genes of known functions, showed broad involvement in metabolic processes (31%), cell structure and motility (20%), gene and protein expression (12%), cell signaling and cell communication (8%), cell division (4%), and notably, 25% of those genes were related to immune function. They included stress response genes, complement-like genes, proteinase and proteinase inhibitors, immune recognition receptors and immune effectors. The EST collection obtained in this study provides a useful resource for gene discovery and especially for the identification of host-defense genes and systems in scallops and other molluscs. (C) 2009 Elsevier Ltd. All rights reserved.

Recent 2000-year geological records of mud in the inner shelf of the East China Sea and their climatic implications

AXIS(14)C dating and grain-size analysis for Core DD2, located at the north of the Yangtze River-derived mud off the Zhejiang-Fujian coasts in the inner shelf of the East China Sea, provide us a high-resolution grain-size distribution curve varying with depth and time. Data in the upper mud layer of Core DD2 indicate that there are at least 9 abrupt grain-size increasing in recent 2000 years, with each corresponding very well with the low-temperature events in Chinese history, which might result from the periodical strengthening of the East Asian Winter Monsoon (EAWM), including the first-revealed maximum temperature lowering event at around 990 a BP. At the same time, the finer grain size section in Core DD2 agrees well with the Sui-Tang Warming Period (600-1000 a AD) defined previously by Zhu Kezhen, during which the climate had a warm, cold and warm fluctuation, with a dominated cooling period of 750-850 a AD. The Little Ice Age (LIA) can also be identified in the core. It starts around 1450 a AD and was followed by a subsequent cooling events at 1510, 1670 and 1840 a AD. Timing of these cold events revealed here still needs to be further verified owing to some current uncertainty of dating we used in this study.

扇贝大防御素和G型溶菌酶的基因克隆与重组表达

扇贝养殖是我国传统的海水养殖产业，但自1997 年以来，养殖扇贝陆续爆发的大规模死亡，不但造成了巨大的经济损失，而且严重影响了该产业的健康发展。扇贝病害的不断爆发以及病因的多样性迫切要求制定新的疾病防治措施和开发新型的抗菌物质。 从扇贝自身的免疫防御因子入手，筛选和克隆参与免疫防御的功能基因，一方面可以研究抗病功能基因在病原感染或环境胁迫条件下的表达规律，深入探讨扇贝的免疫防御机制，并可作为抗病良种选育的分子标记，指导扇贝的遗传改良和抗病品系的培育；另一方面，可对抗菌效应物实现重组表达，开发新型的病害预防治疗制剂，取代目前普遍使用的抗生素和化学药物。抗菌效应物是机体在免疫应答过程中产生的多肽类物质，对侵入生物体内的细菌、病毒具有很强的免疫杀灭作用，对抗菌效应物的研究有助于深入了解机体先天性免疫防御的机制。 本研究采用大规模EST测序方法，结合cDNA末端快速扩增（RACE）技术，从海湾扇贝血淋巴中克隆到了大防御素基因（big defensin, AiBD）的全长cDNA序列，该cDNA全长为531 bp，其中5' 非编码区（UTR）为24 bp，开放阅读框（Open Reading Frame, ORF）含有369 bp，编码122 个氨基酸残基；随后为138-bp 的3' UTR，包括一个多聚腺苷酸信号序列（AATAAA）和ploy A尾巴。分析表明，海湾扇贝大防御素是以前体的形式合成，前体分子包括信号肽、前域和成熟肽三部分。采用Northern blot方法，以DIG标记的DNA探针检测了 AiBD mRNA在不同组织中的表达。结果发现，AiBD 基因的转录本主要在血淋巴中表达，在鳃中也有微量的表达，而在外套膜、闭壳肌、性腺及肝胰腺中检测不到杂交信号。采用QRT-PCR（quantitative real time PCR）对鳗弧菌感染后海湾扇贝血淋巴中AiBD mRNA 的表达量进行了检测，结果发现在感染后8 h 内， AiBD mRNA 的相对表达量平缓升高；随着刺激时间的增长，AiBD基因的mRNA表达量急剧增加，在刺激后16 h 和32 h 分别达到了空白组的72.3 倍和131.1 倍。为了研究海湾扇贝大防御素的抗菌活性，将其成熟肽编码区克隆到毕赤酵母表达载体pPIC9K并实现了重组表达。抑菌实验表明，重组AiBD具有广谱的抗菌活性，其对供试的三株革兰氏阳性菌（藤黄微球菌、溶壁微球菌、金黄色葡萄球菌）都表现出显著的抗菌活性，而对革兰氏阴性菌（鳗弧菌、亮弧菌）的抑菌活性则相对较弱；此外，重组AiBD对表达宿主也表现出杀菌活性，证明其具有抗真菌活性。 根据栉孔扇贝G 型溶菌酶基因的cDNA序列，利用构建的Genome Walking 文库获得了栉孔扇贝G 型溶菌酶基因的全长序列，该基因序列全长为8131 bp，由六个外显子和五个内含子组成。六个外显子长度分别为55 bp，60 bp，90 bp，113 bp，145 bp 和140 bp；五个内含子的长度分别为1126 bp，2161 bp，2744 bp，750 bp和592 bp；内含子的两侧都具有RNA正确剪接所必需的识别位点（GT/AG）。利用TRANSFAC 软件对栉孔扇贝G 型溶菌酶基因的5' 侧翼序列分析发现，该基因的5' 侧翼具有 TATA box 和 CAAT box 的共有序列；此外，在该基因的5' 侧翼发现了C/EBP、NF-κB、OCT-1 和 NF-IL6 等参与免疫基因激活的转录因子潜在结合位点。采用Northern blot方法，以生物素标记的RNA 探针检测了栉孔扇贝G 型溶菌酶基因在不同组织中的表达。结果发现，该基因的转录本主要在鳃、性腺及肝胰腺中表达，在血细胞和外套膜中也有微量的的表达，而在闭壳肌中检测不到杂交信号，这表明栉孔扇贝G 型溶菌酶可能兼备参与机体免疫防御和消化的功能。为了研究栉孔扇贝G 型溶菌酶的抗菌活性，将其成熟肽编码区克隆到毕赤酵母表达载体pPIC9K并实现了重组表达。抑菌实验表明，重组产物具有显著的抗阳性菌活性，其对供试的藤黄微球菌、溶壁微球菌表现出明显的抑制作用，对金黄色葡萄球菌未检测到抑制活性；而对革兰氏阴性菌仅表现出微弱的抑菌活性（亮弧菌和鳗弧菌），对大肠杆菌则基本无抑制活性。

浅海鱼类网箱养殖的关键生态过程及容量评价

随着养殖规模扩大， 放养量超过水域的容纳量，养殖自身污染加重。网箱养鱼的养殖容量研究很有意义。本文对网箱养殖的关键生物过程，物理过程和生物地球化学过程进行了研究，并以模型试验进行了容纳量的评价。 关键物理过程研究得出爱莲湾海水交换周期为2.9 d。 关键生物过程研究：生物能量学模型和现场调查结合，估算了网箱养殖废物的输出。生产周期内，仅抗风浪网箱养殖区，约有48 t DO被养殖鱼类消耗，此外养殖鱼类在养成期输出3.76t氨氮，12.37t（干重）颗粒物；挂网实验和培养实验结果表明每个筏式网箱的污损生物会增加养殖水域N，P负荷的1~2%；用矩估计法，估计了野生许氏平鲉Sebastodes fuscescens的丰度为0.01ind.m-2。 关键生物地球化学过程研究：用沉积物捕捉器研究了沉积物颗粒物在网箱内外沉降同量的区位差异；经验公式并结合现场实验分析认为8月有机物的积聚速度最大，而12月积聚速度最小。 养殖容量和环境容量的评价：利用局部微分方程组和Matlab7.0成功模拟了桑沟湾浮游植物对规模化养殖的响应；以浮游植物的缺失为标志，估算了桑沟湾的养殖潜力；数值模拟了环境因子对规模化鱼类养殖的响应；提出了水生养殖系统健康的评价标准；在数值模拟的基础上，以水质标准，得到爱莲湾养殖环境总容量,0.08V（ind.; V为水域容积，m3）；以生态系统健康为标准，得到养殖总容量，0.27V；建立了筏式网箱养殖容量的简化概念模型，并在此基础上得到了爱莲湾筏式网箱（5 5 5m）养殖容量为单箱放养484尾，和目前爱莲湾筏式网箱的每箱放养量基本相当。

A comparison of future increased CO2 and temperature effects on sympatric Heterosigma akashiwo and Prorocentrum minimum

Very little is known about how global anthropogenic changes will affect major harmful algal bloom groups. Shifts in the growth and physiology of HAB species like the raphidophyte Heterosigma akashiwo and the dinoflagellate Prorocentrum minimum due to rising CO2 and temperature could alter their relative abundance and environmental impacts in estuaries where both form blooms, such as the Delaware Inland Bays (DIB). We grew semi-continuous cultures of sympatric DIB isolates of these two species under four conditions: (1) 20 degrees C and 375 ppm CO2 (ambient control), (2)20 degrees C and 750 ppm CO2 (high CO2),(3) 24 degrees C and 375 ppm CO2 (high temperature), and (4) 24 degrees C and 750 ppm CO2 (combined). Elevated CO2 alone or in concert with temperature stimulated Heterosigma growth, but had no significant effect on Prorocentrum growth. P-Bmax (the maximum biomass-normalized light-saturated carbon fixation rate) in Heterosigma was increased only by simultaneous CO2 and temperature increases, whereas P-Bmax in Prorocentrum responded significantly to CO2 enrichment, with or without increased temperature. CO2 and temperature affected photosynthetic parameters alpha, Phi(max), E-k, and Delta F/F'(m) in both species. Increased temperature decreased and increased the Chl a content of Heterosigma and M Prorocentrum, respectively. CO2 availability and temperature had pronounced effects on cellular quotas of C and N in Heterosigma, but not in Prorocentrum. Ratios of C:P and N:P increased with elevated carbon dioxide in Heterosigma but not in Prorocentrum. These changes in cellular nutrient quotas and ratios imply that Heterosigma could be more vulnerable to N limitation but less vulnerable to P-limitation than Prorocentrum under future environmental conditions. In general, Heterosigma growth and physiology showed a much greater positive response to elevated CO2 and temperature compared to Prorocentrum, consistent with what is known about their respective carbon acquisition mechanisms. Hence, rising temperature and CO2 either alone or in combination with other limiting factors could significantly alter the relative dominance of these two co-existing HAB species over the next century. (c) 2007 Elsevier B.V. All rights reserved.

青海栽培何首乌不同部位中蒽醌类成分的测定

用高效液相色谱法测定青海栽培何首乌中的主要有效成分大黄素、大黄素甲醚等蒽醌类成分。采用kromasil C18柱（4．6mm i．d．×250mm，5μm）；V（甲醇）：V（水）：V（H3PO4）=750：250：0．001为流动相，检测波长为254nm，流速为1mL／min，进样量10μL。用此方法测定青海栽培何首乌不同部位中的蒽醌类成分，大黄素和大黄素甲醚达到基线分离，线性范围分别为0．094～1．50／μg（r=0．9992），0．094～1．50／μg（r=0．9997），回收率分别为大黄素95％、大黄素甲醚102％。实验发现青海栽培何首乌块根中大黄素和大黄素甲醚成分较藤、叶中高，大黄素含量比大黄素甲醚含量高。

巨穗小麦种质株高的基因定位

巨穗小麦新种质材料是一种有茎杆粗壮、叶片短宽直立、大穗、大粒 、高结实率等特点的种质资源。本研究应用单体分析和双端体分析方法对“241”材料进行了遗传学研究。结果表明，小麦新种质材料“241”的1A、3A、5A和4B染色体上具有控制株高的隐性基因，6B染色体上具有控制株高的显性基因，其中3A、5A和6B染色体上的基因表现为强效，1A和4B染色体上的基因表现为弱效。通过双端体分析进一步将控制株高的基因定位到1AS、3AS、5AL和4BL上。

Effect of microwave treatment on chemical composition and in sacco digestibility of wheat straw in yak cow

Wheat straw was treated with microwave for 4 min and 8 min at a power of 750 W and frequency of 2,450 MHz. Chemical compositions of untreated, 4 min treated and 8 min treated Straws were analyzed and in sacco degradabilities of all these straws in yak rumens were measured. Microwave treatment didn't significantly (p > 0.05) affect the chemical composition of the straw. In sacco dry matter (DM) degradability of the straw after 18 h incubation in rumen was significantly (p < 0.01) improved by microwave treatment. In sacco crude protein (CP) degradability of the straw was not (p > 0.05) affected by microwave treatment. In sacco organic matter (OM) degradability of the straw was increased (p < 0.01) by around 20% for both the 4 min and 8 min microwave treatment, that of acid detergent fibre (ADF) was increased (p < 0.01) by 61.6% and 62.8%, and that of ash free ADF was enhanced by 72.1% and 69.6% for the 4 min and 8 min microwave treatment respectively. No significant difference was observed between the 4 min and 8 min microwave treatment on the degradability of DM, OM, CP, ADF and ash-free ADF of the straw.

基于启发式节点增强策略的PRM路径规划方法

针对一般的PRM方法用于移动机器人对复杂地形路径搜索存在的缺陷 ,本文对PRM方法进行了改进 ,提出了一套基于启发式的节点增强的策略 ,提高了PRM方法节点增强阶段对环境的适应性 .此外 ,本文建立了相应的仿真实验系统对策略的有效性进行了实验与分析