A study of liquid-phase catalyst systems for selective oxidation of methane

甲烷选择氧化活化一直是催化化学领域中具有重要学术意义和应用背景的热点和难点课题之一，研究工作十分活跃。液相催化体系中甲烷的选择氧化活化已成为多相催化体系的重要补充，加之不同溶剂体系中甲烷转化的效率差别较大，使其内涵更加丰富。本学位论文根据国内外液相体系甲烷选择性催化氧化的研究进展，开展了发烟硫酸介质中Pd/C催化剂和乙腈介质中双氧水存在下硫酸氧钒催化剂对甲烷选择氧化活化的研究，取得以下主要结果。(1)以二氯化钯为前驱体，采用浸渍法制备了一系列不同钯负载量的活性炭负载型Pd/C催化剂，研究其在发烟硫酸体系中甲烷氧化制硫酸单甲酯、进而水解制得甲醇的催化性能。结果表明，该体系的液相主要产物是硫酸单甲...Selective oxidation of methane to produce oxygenates remain one of the challenges in catalysis field. The reaction carried out in liquid phase with homogeneous catalysts becomes an important topic in this area due to its much gentle conditions over heterogeneous system. The conversion and selectivity varies in different solvent system which further enrich its connotation. In the present work, the ...学位：理学硕士院系专业：化学化工学院化学系_物理化学(含化学物理)学号：20042509

眼镜蛇毒因子抑制补体激活对脓毒症大鼠血清细胞因子的影响

目的:观察眼镜蛇毒因子(cobra venom factor,CVF)对脓毒症大鼠外周血中肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)和白介素-10(IL-10)的影响。方法:选取清洁级雄性SD大鼠144只,按照随机数字表法将大鼠分为A组(假手术组)、B组(脓毒症组)、C组(CVF预处理组),各48只;各组按照标本采集点的不同又分为术后2、4、8、12、16、24 h六个时间点亚组,各8只。B、C组采用盲肠结扎穿孔术(CLP)制作脓毒症大鼠模型;C组大鼠在CLP术前静脉注射CVF,而A、B组静脉注射等量0.9%氯化钠溶液。观察术后大鼠一般情况及腹腔情况,比较各组术后不同时间点的TNF-α、IL-6和IL-10水平变化。结果:C组大鼠脓毒症反应较B组明显减轻;除术后8 h外,C组术后其他时间点TNF-α水平均低于B组(P<0.05),其中B组术后2 h时TNF-α迅速升高达峰然后下降,但是术后12 h再次升高出现第二个峰值,C组术后4 h较2 h迅速下降,术后8 h再次升高出现第二个峰值;除术后16 h外,C组术后其他时间IL-6水平均低于B组(P<0.01);除术后2、24 h外,C组血清IL-10水平均高于B组(P<0.05),而且术后8、16 h两次达到峰值,呈双峰变化。结论:CVF可以有效维持促炎细胞因子(TNF-α、IL-6)和抗炎细胞因子(IL-10)的平衡并明显抑制脓毒症大鼠的炎症反应,同时TNF-α及IL-10的\"双峰现象\"也为免疫平衡理论及PICS提供了理论依据。江西省自然科学基金资助项目(0440083

Comparison of the preparation methods of Temozolomide-loaded nanoparticles

目的比较载替莫唑胺聚氰基丙烯酸正丁酯纳米粒(TMz-PbCA-nP)的不同制备方法,确定最佳制备工艺。方法以α-氰基丙烯酸正丁酯(bCA)为载体,分别采用乳化聚合法和界面聚合法制备TMz-PbCA-nP,加以吐温-80(T-80)进行表面修饰,并通过zETA电位仪检测纳米粒粒径和电位、透射电镜观察纳米粒形态、紫外分光光度计测定各自的包封率和载药量。结果乳化聚合法制备的TMz-PbCA-nP平均粒径(135.8±11.3)nM,表面电位(-24.8±2.2)MV,包封率(44.23±2.04)%,载药量(2.80±0.05)%;界面聚合法制得的载药纳米粒平均粒径(175.4±10.2)nM,表面电位(-18.3±3.6)MV,包封率(44.35±2.58)%,载药量(2.31±0.47)%。透射电镜下观察两种方法所制备的纳米粒大小均较为均匀,粒子间无明显聚集。结论采用乳化聚合法制备TMz-PbCA-nP效果较优于界面聚合法。【Objective】 To compare Temozolomide polybutylcyanoacrylate nanoparticles(TMZ-PBCA-NP) prepared by two different methods so as to determine the optimal process.【Methods】 TMZ-PBCA-NP was prepared by emulsion polymerization and interfacial polymerization methods separately and the surfaces of the two kinds of nanoparticles were both modified with tween-80(T-80).Zeta potential instrument was used to detect the particle size and charge and transmission electron microscopy was employed to study the particle shape.The entrapment efficiency and drug loading were determined with ultraviolet spectrophotometry.【Results】 The mean particle size,surface charge,entrapment efficiency and drug loading of the NP prepared by emulsion polymerization and interfacial polymerization methods was(135.8±11.3) nm and(175.4±10.2) nm,(-24.8±2.2) mV and(-18.3±3.6) mV,(44.23±2.04) % and(44.35±2.58) %,(2.80±0.05) % and(2.31±0.47) %,respectively.Both nanoparticles had uniform size distribution and no apparent aggregation according to transmission electron microscopy.【Conclusion】 The emulsion polymerization method is better than interfacial polymerization method in preparing TMZ-PBCA-NP.国家自然科学基金(No:81172394

Climate Change Adaptation Policy in Ghana: Priorities for the Agriculture Sector

This report is intended to complement the 2011 CCAFS publication “State of Climate Change Adaptation and Mitigation Efforts for Agriculture in Ghana” (Domozoro 2011). It provides relevant updates regarding the policies, projects, or initiatives introduced therein, and an assessment of the evolving political scenario. Specifically, this document presents an objective look at 17 key policy documents within three thematic areas: (1) governance, (2) agriculture, and (3) climate change institutions in Ghana. Several key projects are also included in this analysis given their relevance and status within Ghana’s agricultural adaptation regime. A discussion of the institutional arrangements in each of the thematic areas is provided first, along with a short description of each of the 17 policies and projects. Then, in the following analysis section, objectives and priorities for each of the policies are outlined, together with their evolution over time, intending to identify the temporal shifts in agricultural climate change policy direction in the country. Policy interplay between and within these thematic areas is also addressed. Power and influence dynamics between actors in Ghana’s climate change adaptation regime are discussed in the following section and the results of a Multilevel Stakeholder Influence Mapping (MSIM) exercise are provided. Finally, a discussion of key challenges and recommendations are provided, as identified through semi-structured interviews with actors across the country’s adaptation regime

Selective Oxidation of Methane to Methanol in Oleum over Pd/C Catalyst

以PdCl2为前驱体,采用浸渍法制备了Pd/C催化剂,并在发烟硫酸中考察了其催化甲烷选择氧化反应的性能,采用X射线粉末衍射、X射线光电子能谱、高分辨透射电镜和CO吸附等方法对催化剂进行了表征.甲烷选择氧化反应得到的主产物硫酸单甲酯经水解后得到甲醇,在5%Pd/C催化剂、Pd用量30μmol、反应温度180℃、反应压力4.0 MPa、反应时间4 h和发烟硫酸中SO3含量为50%的优化工艺条件下,甲烷转化率为23.6%,甲醇的选择性和收率分别为69.5%和16.4%,在一定程度上可实现催化剂的多次重复使用.Pd/C催化剂上的甲烷选择氧化反应可能遵循亲电取代机理,催化性能与Pd负载量、Pd粒子尺寸和分散度等有关.The selective oxidation of methane to methanol over Pd/C catalysts generated from a PdCl2 precursor was investigated in oleum.Characterization of the catalysts was performed by X-ray diffraction,X-ray photoelectron spectroscopy,high-resolution transmission electron microscopy,and CO adsorption.The major product in the oxidation reaction was methyl bisulfate,which was then hydrolyzed into methanol.Methane conversion of 23.6% with methanol selectivity of 69.5% and yield of 16.4% was achieved under the optimum conditions of 5%Pd/C,30 μmol Pd,reaction temperature 180 ℃,methane pressure 4.0 MPa,reaction time 4 h,and 50% sulfur trioxide concentration.After facile separation with the reactants and pretreatment,the catalyst could be reused several times with considerable stability.The selective oxidation of methane catalyzed by Pd/C catalysts in oleum possibly involved an electrophilic substitute mechanism.The catalytic performance was related to the Pd loading,dispersion,and particle size.国家自然科学基金(20473065);; 福建省科技重大专项(2005HZ01-3

Preparation and in vitro evaluation of chitosan microspheres containing matrine

目的:以壳聚糖为囊材制备苦参碱结肠靶向给药微球及评价其体外释药情况。方法:用乳化化学交联法制备微球,以微球的粒径分布百分数、载药量及包封率为优化指标对影响微球制备的主要因素用正交试验设计优化制备条件;并对最佳制备工艺制得的微球进行3种不同递质(人工胃液、人工肠液及大鼠结肠液)中的体外释放度评价。结果:制得的苦参碱壳聚糖微球在电镜下,球形表面圆整,粒径分布适宜,微球平均粒径为(68.3±2.7)μm,平均载药量为(16.0±0.5)%,平均包封率为(66.3±4.2)%。苦参碱壳聚糖微球在人工胃液中2h不释药;在人工肠液中4h内释放不到1%,96h释药不到10%;在含大鼠结肠内容物的磷酸盐缓冲液(pH6.8)中4h释放10%左右,36h释药近50%,此后释药趋于缓慢,96h释药近80%。结论:苦参碱壳聚糖微球几乎不在上消化道释药,而是在结肠靶向释药。OBJECTIVE To preparate the chitosan microspheres containing matrine for the colon-specific drug delivery and evaluate its release in vitro.METHODS The chitosan microspheres containing matrine were prepared by emulsion-chemical crosslink technique.The better preparation procedure with respect to particles size distribution,embedding rate and drug loading were optimized by the orthogonal experimental design.In-vitro drug release were carried out in the artificial gastric,artificial intestinal and the phosphate buffered saline(pH(6.8)) containing rat colon contents.RESULTS The chitosan microspheres containing matrine was shown to have good spherical geometry,a smooth surface and suitable size distribution under scanning electron micrographs.Average diameter of microspheres was((68.3)±(2.7))μm,drug loading was((16.0)±(0.5))%,embedding rate ((66.3)±(4.2))%.Little release and a little release of matrine from the microspheres were observed in the artificial gastric juice and in the artificial intestinal juice,respectively.However,the release of matrine was markedly increased in the phosphate buffered saline(pH(6.8)) containing rat colon contents,which was near to 10%,50% and 80% at 4 h,36 h and 96 h,respectively.CONCLUSION These findings suggest that the chitosan microspheres containing matrine may be useful a dosage form for colon-specific drug delivery.甘肃省自然科学基金(编号ZS0001-A23-073-Y

Physiological effects of methmidophos and phoxim on Porphyra haitanensis

In this paper, the effects of methmidophos and phoxim with different concentrations and schedule on soluble protein content and chlorophyl a (Chla) content in Porphyra haintanensis were studied under experimental and ecological conditions. The results showed as follows: (1) there were some time-effect and dose-effect relationships between the pollutants and Chla contents. The Chla content of most of groups decreased with the increasing of dose and prolonging of the exposure time. In the same concentration, the toxicities of phoxim to Chla content was stronger than that of methmidophos. (2) All concentration groups in this study didn't show the significant time-effect and dose-effect relationships between pollutants and the soluble protein. And there was no significant difference of the soluble protein content among various groups.福建省重大科技项目(2001Z017

武夷山市洲庵遗址考古发掘简报

洲庵遗址位于福建省城村汉城遗址西南2公里处,2013年被调查发现。随后对其进行抢救性考古发掘,共发现汉代房址1处,宋代灰坑6个、窑炉3座,出土一批汉代、宋代建筑材料、陶瓷器标本,这为研究..

Selective oxidation of methane to methanol in oleum over Pd/C catalyst

The selective oxidation of methane to methanol over Pd/C catalysts generated from a PdCl2, precursor was investigated in oleum. Characterization of the catalysts was performed by X-ray diffraction, X-ray photo-electron spectroscopy, high-resolution transmission electron microscopy, and CO adsorption. The major product ill the oxidation reaction was methyl bisulfate, which was then hydrolyzed into methanol. Methane conversion of 23.6% with methanol selectivity of 69.5% and yield of 16.4% was achieved under the optimum conditions of 5% Pd/C, 30 mu mol Pd, reatction temperature 180 degrees C, methane pressure 4. 0 MPa, reaction time 4 h, and 50% sulfur trioxide concentration. After facile separation with the reactants and pretreatment, the catalyst could be reused several times with considerable stability. The selective oxidation of methane catalyzed by Pd/C catalysts in oleum possibly involved an electrophilic substitute mechanism. The catalystic performance was related to the Pd loading, dispersion, and particle size

Compositional and structural characterization of marine organic colloids-an overview

国家自然科学基金项目(49976021);; 国家重点基础研究发展规划项目(G2000078500);; 杰出青年基金项目(49825162