250 research outputs found

    福建农村生态文明监测体系构建及测评

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    在对农村生态文明的含义和内容进行辨析的基础上,选取了30个反映自然生态保护、农村经济发展和生态文明管理体制的代表性指标,使用主成分分析法和层次分析法,构建了福建农村生态文明建设监测体系。并通过实际数据的测算,对福建9个设区市的农村生态文明情况进行了比较。在此基础上,提出了加强福建农村生态文明建设的若干政策建议

    转型期中国金融排斥困境及其对县域经济发展的影响——基于中国2 574个县(市)数据的空间分析

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    文章以中国2 574个县(市)为样本,采用空间计量分析方法刻画我国县域金融排斥的空间分布特征,量化其对县域经济发展的影响。研究发现:金融排斥在地理分布上具有显著的空间正相关关系,即不仅对本县(市)的经济发展具有显著的负面影响,还对其他县(市)有显著的负溢出效应;东部地区金融排斥的空间分布以低—低集聚和低—高集聚为主,而中西部地区则以低—高集聚为主,其中,中部地区形成了以高金融排斥集聚区包围多经济中心的空间分布格局,而西部地区则呈现出大片高金融排斥集聚区包围单经济中心的空间格局;发达地区地方政府的干预限制了金融集聚的空间溢出效应,使落后地区(特别是农村地区)长期陷入金融排斥的不利境地。研究不仅为普惠金融战略的精准实施提供了大样本的直观证据,还以典型地区为样本,深入分析了金融排斥的地区分布特征以及对地区经济的影响,为制定针对性更强的应对措施提供政策参考。中央高校基本科研业务费专项项目“‘一带一路’建设民心相通框架下孔子学院跨文化传播研究”(2018CDXYJG0040)重庆大学研究生重点课程建设项目“高级计量经济学”(201805055

    可见光催化环丙基胺与1,2-二酮衍生物的[3+2]环加成反应

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    本文报道了一种可见光催化环丙基胺与1, 2-二芳基乙二酮衍生物的[3+2]环加成反应,合成了一系列α-氨基呋喃衍生物,该反应条件温和,产率良好,操作简单。这一方法为潜在生物活性分子骨架α-氨基呋喃衍生物的合成提供了一条高效便捷的路径

    可见光催化环丙基胺与1,2-二酮衍生物的[3+2]环加成反应

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    报道了一种可见光催化环丙基胺与1,2-二芳基乙二酮衍生物的[3+2]环加成反应,合成了一系列α-氨基呋喃衍生物,该反应条件温和,产率良好,操作简单.这一方法为潜在生物活性分子骨架α-氨基呋喃衍生物的合成提供了一条高效便捷的路径.国家自然科学基金(No.21572184)福建省自然科学基金(No.2017J06006)中央高校基本科研业务费(No.20720160027)资助项目~

    Biomass Cell Wall Component Structural Interpretation and Bonding Mechanism

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    生物质转化为高值化材料的关键一步是对组分进行清洁温和分离,然后将分离后的组分进行生物和化学转化,获得高性能材料。然而,由于生物质结构复杂,人们对其了解的局限导致对它们有效分离缺乏理论上的指向,使得目前的分离技术多是一种工艺层面的探索。迄今为止,尚没有高效的集成化生物质清洁分离技术体系,即在一个工艺过程中将生物质不同的组分能以较完整的分子结构形式清洁有效分离出来。由于生物质现代转化利用途径需要在保持较完整结构的基础上将主要组分清洁有效分离开来,然后对不同组分进行有目的的转化利用。因此,尽管生物质组分转化利用有广阔的应用前景,但生物质组分的清洁有效分离仍是一个瓶颈限制,是一个难点问题。生物质组分分离的关键是将断裂木质素组分和半纤维素组分之间的结合键或有选择性断裂木质素分子内的结合键,进一步达到清洁分离组分的目的。该研究拟从生物质组分间化学结合键的差异性以及空间构型的差异性中寻找其对不同差异介质环境中的反应机制,从而进一步提出氧基化学分离新途径的导向指引,即利用木质素侧链的α、β、γ-与半纤维素组分之间的酯键等结合键或木质素分子内不同化学键对不同微差异介质环境中化学体系中O2分子的敏感性不同,探索其可能的分子内或分子外结合键的断裂途径,从而实现清洁温和分离纤维素、半纤维素和木质素组分的目的,为生物质的高值化利用奠定基础。The key procedure of converting the biomass into high value materials is to separate the fractions clean and moderately and then to conduct the biological or chemical conversion of the separated fractions to obtain the high value materials. However, it, the lack of theoretical guide of effective separation on account of the limitation of our acquirement about the complexity of biomass structure, makes the separation technology become an exploration on process level. So far, there is no efficient integrated system for clean separation, which can separates different fractions at a fairly complete molecular structure clean and effectively in a process. The way of modern biomass utilization needs to separate its fractions clean and effectively under the premise of a fairly complete molecular structure and then carry out the purposeful conversion and utilization of different fractions. Despite the biomass conversion and utilization have broad application prospects, the clean and effective separation is still a bottleneck restriction and a difficult problem. The key to the separation of biomass components is to break the bond between lignin and hemicellulose or to selectively break the intramolecular bond among lignin achieving the purpose of clean separation. This study intends to find the reaction mechanism under different medium environment from the differences of the bonds among the fractions and the differences of spatial configuration, and then propose an orientation guidance of oxygen chemical separation. Scilicet, making use of the different sensitivities to O2 of different bonds, which between lignin side chain of alpha, beta, gamma- and bonds among hemicellulose fractions, such as easter bond, or intramolecular bond among lignin molecules, to explore the possible fracture way in or between the molecular. Furthermore, on the basis of the above work, this study intends to achieve the purpose of a clean and moderate separation of cellulose, hemicellulose and lignin fractions, laying a foundation for high value utilization of biomass

    Superparamagnetic core-shell polymer particles for efficient purification of his-tagged proteins

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    地址: 1. Xiamen Univ, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 2. Xiamen Univ, Coll Chem & Chem Engn, Dept Chem, Xiamen 361005, Peoples R China 电子邮件地址: [email protected] core-shell Fe3O4@SiO2@poly(styrene-alt-maleic anhydride) spheres enriched with Ni-NTA on their surface have been prepared by precipitation polymerization. The spheres have a core composed of superparamagnetic polycrystalline magnetite having a uniform size of similar to 220 nm, endowing the spheres with excellent magnetic responsivity and dispersity. The shell composition of poly(styrene-alt-maleic anhydride) allows the incorporation of more Ni-NTA affinity sites onto the surface of the magnetic spheres. Owing to the multivalency effect, the separation capacity of His-tagged proteins by the as-prepared Fe3O4@SiO2@polymer/Ni-NTA composites was four times as that by Fe3O4@SiO2/Ni-NTA, making them particularly promising for the magnetic separation of low-concentration His-tagged proteins. The magnentic polymer hybrid particles also exhibited excellent performance in the direct separation of His-tagged proteins from cells lysates.NSFC 20925103,20871100,20721001 Fok Ying Tung Education Foundation, 121011 MSTC,2009CB930703;NSF of Fujian Province 2009J06005; Key Scientific Project of Fujian Province 2009HZ0002-

    小潮气量机械通气期间肺开放策略对肺损伤标志物的影响

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    【目的】探索外科手术中小潮气量机械通气期间应用间断肺复张手法(RM)联合中等水平呼气末正压(PEEP)构成的肺开放策略(OLS)对血浆中肺损伤标志物晚期糖基化终产物可溶性受体(sRAGE)及Clara细胞蛋白(CC16)浓度的影响。【方法】本研究纳入行择期腹腔镜结直肠癌切除术的患者100例,随机(1∶1)分为开放策略组(OLS)和非开放策略(NOLS)组。两组均使用小潮气量机械通气;OLS组机械通气期间间断给予RM并设置PEEP为6~8cmH2O,NOLS组不予RM及PEEP。麻醉诱导前(T1)、术毕后即刻(T2)及术后第3天(T3)分别取血检测血浆sRAGE、CC16浓度。【结果】在T1、T2、T33个时间点,血浆sRAGE、CC16浓度组间均无统计学差异(>0.05)。所有患者中,T2、T3sRAGE浓度高于T1,T3sRAGE浓度高于T2,T3CC16浓度高于T1、T2,均有统计学差异(<0.05)。【结论】术中小潮气量机械通气期间,应用间断RM联合中等水平PEEP的肺开放策略不能改变术后三天内血浆肺损伤标志物sRAGE和CC16的水平

    Bacterial Conversion of Sulfur-and Phosphorous-Compounds and Microbial Diversity in Sediments from a Near-Shore Marine-Cultural Region

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    对福建某近海养虾场底泥环境中硫和磷 2种元素的微生物代谢进行了研究 .结果表明 ,细菌代谢有机硫和无机硫产H2 S是养殖过程中造成H2 S污染的主要因素 ,利用半胱氨酸和硫代硫酸钠产生硫化氢的细菌数量分别为 1 .6× 10. 6和 4 . 35× 10. 3个·g-1底泥 ;进一步研究发现 ,芽孢杆菌属、盐芽孢杆菌属和微杆菌属等细菌是产H2 S的优势菌群 ,而硫酸盐还原菌的数量较少 ,仅为 2 5个·g-1,其产H2 S的作用不明显 .研究还发现 ,转化有机磷和无机磷酸盐的优势菌群属于好氧细菌 ,其中分解卵磷脂的细菌和产磷酸酯酶细菌的数量分别为 2 . 17× 10. 5和 1 2. 1× 10 6个·g-1,转化磷酸钙的细菌数量为 6 . 96× 10 3 个·g-1.本文从微生物学的角度探讨了养殖环境中硫、磷化合物的转化 ,提出细菌好氧代谢产H2 S是养殖环境潜在的污染因素 ,给出了一些改善和修复养殖环境生态的建议 .The H_2S-producing bacteria and the phosphorous-cycling bacteria in sediments from near-shore marine-cultural region were investigated. Results indicate that the bacterial H_2S production in aerobic condition is the dominating process to produce H_2S in the sediment of cultural pond. The total counts of H_2S-producing bacteria utilizing cysteine and Na_2S_2O_3 were 1.6×106 and 4.35×103 cells g -1 respectively. The counts of sulfate-reducing bacteria in the sediments were very little, only 2.5×101 g -1. Further results show that the bacterial counts of decomposing lecithin and secreting phosphatase were 2.17×105 and 1.21×106 g -1 respectively, bacterial counts of dissolving Ca_3PO_4 were 6.96×103 g -1. Traditional taxonomy and partial 16S rRNA gene sequencing on the H_2S-producing and phosphate-cycling bacteria indicate that most isolates could be classified as members of the following Genera: Bacillus, Halobacillus, Microbacterium, etc.中国科学院知识创新工程项目 (KZCX1 SW 12 Ⅱ ) ;; 中国科学院百人计划项目

    ECOLOGICAL CHARACTERIZATION OF BACILLI IN SEDIMENT FROM A NEAR-SHORE MARINE HORTICULTRTAL REGION

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    通过对近海养虾场底泥中的细菌数量和类群的调查 ,发现有超过 5 0 %的细菌生物量是产芽孢细菌 ,因此对底泥中的产芽孢细菌进行了分离和纯化 ,通过对细胞形态、生理生化等特征的研究和对部分菌株的 16SrRNA基因的ARDRA分型、序列分析等 ,鉴定了 6 7株产芽孢细菌 ,其中 6 2株属于芽孢杆菌属 ,5株属于短芽孢杆菌属 .进一步对 6 2株芽孢杆菌属的细菌在底泥不同深度的分布进行研究 ,结果表明 ,巨大芽孢杆菌主要分布在底泥深度 0~ 6cm左右的区域 ,海洋芽孢杆菌、短小芽孢杆菌和蜡状芽孢杆菌主要分布于底泥 6cm以下的区域 ,与坚强芽孢杆菌性状相近的菌分布在底泥 2~ 8cm深度 ;与耐碱芽孢杆菌性状相近的芽孢菌广泛分布在 0~ 12cm区域 .讨论认为 ,应用这些产芽孢细菌资源在修复海洋环境和开发海水养殖微生态制剂方面具有一定可能性 .图 3表 3参 15A survey on microbial populations in the sediment from a near-shore mariculture region revealed that over 50% (by cells) of the biomass was spore-producing bacteria. Totally 67 strains of spore-producing bacteria were obtained and were identified by their cellular morphology, physiological and biochemical features. 12 of the 67 strains were further characterized by cloning their 16S rRNA genes. Results indicate that 62 out of the 67 spore-producing bacterial strains belong to the genus Bacillus and 5 strains belong to Brevibacillus. Among the 62 strains of Bacillus, B. megaterium, B. marinus, B. pumilus, B. cereus, B. thuringensis, B. sphaericus and B. firmus were identified, while other 28 strains could not be taxonomically identified and need further studies. The strains of B. megaterium mainly distributed in the zone above 6 cm of the sediments, and B. pumilus and B. cereus were dominant species in the sediment under depth of 6 cm. The unidentified bacilli distributed through out the entire zone (0~12 cm) of the sediment. The possibility of applying these bacilli for bioremediation of the polluted marine environments or for developing ecological preparations for horticultural is discussed. Fig 3, Tab 3, Ref 15中国科学院知识创新工程项目 (KZCX1 SW 1 2 Ⅱ );; 百人计划支持项目~

    Analysis of Nitrate Reducing Community in a Near-shore Marine-cultural Sediments

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    通过对福建省沿海海水养殖场沉积物中参与氮循环的各生理群细菌数量分析 ,发现氨化和硝酸盐还原细菌是优势生理菌群 ,同时 ,表层泥样中的硝酸盐还原菌数量明显高于深层泥样。从该环境中分离获得 1 0 6株细菌 ,其中 5 8株具有硝酸盐还原能力 ,初步鉴定表明它们主要为芽孢杆菌属 (Bacillus)、盐芽孢杆菌属 (Halobacillus)、短芽孢杆菌属 (Brevibacil lus)、动性球菌属 (Planococcus)和动性杆菌属 (Planomicrobium)等革兰氏阳性细菌的成员 ;1 6SrRNA基因序列分析进一步证实该环境中的硝酸盐还原菌具有丰富的多样性The nitrogen-cycling bacteria in a near-shore marine-cultural sediments were investigated. Results indicated that ammonifying and nitrate-reducing bacteria (NRB) were the most abounding populations. The abundance of nitrate-reducing bacteria occurred in the surface layer of the sediment was higher than that in the bottom layer. 106 bacterial strains were obtained from sediment samples and were tested for their nitrate reducing ability. The results showed that 58 strains of them were able to reduce nitrate. The dominant nitrate-reducing strains were preliminarily identified as Gram positive bacteria and belong to the genus of Bacillus, Halobacillus, Brevibacillus, Planococcus and Planomicrobium.The richness of diversity of nitrate-reducing bacteria was further revealed by the analysis of the sequences of their 16S rRNA genes
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