42 research outputs found

    公共产品虚拟价值的影响因素分析及核算:以空气污染为例

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    广义虚拟经济是指同时满足人的生理需求和心理需求并以心理需求为主导,以及只满足人的心理需求的经济的总和。中国城市化和现代化进程的不断推进,带来的不仅仅是持续高效的经济增长,还有一系列的环境问题,其中空气污染最为严峻和突出。清洁的空气是公共产品,不具有价格,在广义虚拟经济学下呈现出虚拟价值的形态。本文通过深入分析虚拟价值的内涵,构建清洁空气虚拟价值影响因素的理论框架并作出相应假设,最后进行实证分析,得出结论并提出治理空气污染的解决措施。广义虚拟经济专项资助项目[项目编号:GX2014-1020(M)

    First-Principles Study of Effect of Strain on the Band Structure of ZnO Monolayer

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    采用基于密度泛函理论的第一性原理计算对单层znO薄膜能带结构的应变调控进行了研究.计算结果表明:沿着之字形方向的压缩应变和扶椅形方向的拉伸应变对薄膜带隙的调控都是线性的,而且带隙调控的范围最大;相反地,在沿着之字形方向的拉伸应变和扶椅形方向的压缩应变的调控下,带隙则呈现出非线性的变化.对于双轴应变的拉伸与压缩,带隙的变化都是非线性的.这种通过不同的应变加载方式来实现对带隙不同程度的调控,对znO薄膜在光学和催化等领域的应用具有重要的指导意义.The effect of strain on the band structure of the ZnO monolayer has been investigated by firstprinciples calculations based on density functional theory.The results reveal that the band structure of the ZnO monolayer presents different dependences on three types of strain.The band gap linearly and steeply varies under uniaxial zigzag compressive strain and armchair tensile strain, while it shows nonlinear dependence on the other types of strain.Therefore, uniaxial zigzag compressive strain and armchair tensile strain should be the most effective to tune the band gap.This work has significant implications for application of strain to tune the optical and catalytic properties of ZnO nanofilms.国家自然科学基金(10702056;11204252); 四川省教育厅(12ZA072)资助项目~

    ANALYSES ON LDH ISOENZYME AND PROTEIN FROM BOTH GUANGDONG STRAIN AND FUJIAN STRAIN OF ECHINOCHASMUS FUJIANENSIS

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    目的 探讨福建与广东两地福建棘隙吸虫生化特点。方法 用不连续聚丙烯酰胺凝胶电泳及薄层等电聚焦电泳等进行比较分析虫体乳酸脱氢酶 (LDH)同工酶和蛋白质。结果 福建与广东两地虫株都有 5种LDH同工酶 ,其中LDH1、LDH4 和LDH5的迁移率相同 ;蛋白质电泳都分离出 9条区带 ,其中有 7条带的等电点相同。但在LDH2 和LDH3 的迁移率 ,蛋白质区带的相对含量 ,同工酶的总活力与比活力 ,以及A和B亚基的含量等存在差异。结论 LDH同工酶与蛋白质的某些差异 ,可归因为基因型相似条件下所出现两地虫株生化遗传上差异Aim\ Inguired into the biochemical characteristrics of Echinochasmus fujianensis found in Fujian and Guangdong provinces. Methods\ Compared and analysed two strains by LDH isoenzyme eletrophoresis, discontinuous PAGE and thinlayer isoelectric equilibrium PAGE.Results\ Two strains both had five LDH isoenzyme, among them, LDH\-1、LDH\-4 and LDH\-5 had the same mobilities. There were nine bands in protein electrophoresis. Seven bands had the same isoelectric point.But there were differences in the mobilities of LDH\-2 and LDH\-3,the comparative amount of protein bands, total and specific activity of isoenzyme and the amount of A and B subunit. Conclusion Under the similar condition of genotypes, the differences of the biochemical inheritance can be contributed to the differences of LDH isoenzyme and protein.福建省科技计划基金资助项目!(No.98-Z-156);; 福建省“百千万人才”人选培养资金资助项

    Tendency and critical scientific issues of space life science in China

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    空间生命科学是随着人类空间探索活动,特别是载人空间探索而产生和发展的新兴交叉学科,它涵盖了较为广泛的研究范围.在过去半个多世纪,国际上在该领域取得了许多重要发现和研究成果,不仅支撑了载人空间探索任务,同时也服务了地球人类的生活.随着我国载人航天和深空探索活动的不断发展,特别是我国载人空间站工程的启动,未来20年将是我国空间生命科学发展的黄金时期.基于我国的载人空间站和返回式科学卫星实验平台,开展空间生命科学研究,获取新知识、创新新技术,进一步服务于人类空间探索活动、服务国家经济和社会发展,这就需要我们从学科发展的战略高度,系统深入地进行研究思考.在全面回顾国内外空间生命科学的发展历史及现状的基础上,本文对我国空间生命科学的战略需求、发展方向和关键科学问题等进行了梳理、分析和展望,以期为我国空间生命科学的发展提供思路和借鉴.As an emerging interdiscipline, space life science, generated and developed with human space, especially manned space exploration,, covering very wide research fields.In the past more than half a century, many significant findings and achievements have been achieved in this field, which not only supports the missions of manned space exploration, but also provides service for the life on the earth.With the continuous development of Chinese manned space and deep space exploration activities, especially the startup of Chinese manned space station project, the next two decades will be the prime time for the development of Chinese space life science.To conduct space life science, obtain new knowledge and innovative technology and provide further service for human space exploration, national economic and social development basing on Chinese manned space station and return type scientific satellite experiment platform, which need us to study and thinking systematically from the strategic perspective of subject development.By reviewing the historical and current development of space life science at home and abroad, this essay analyzes and prospects the strategic needs, key scientific problems and development direction of Chinese space life science, in order to provide inspiration and reference for its development.国家重点基础研究发展计划(编号:2011CB710903); 中国科学院技术科学部学科发展战略研究课题(我国空间科学发展战略研究)资助项

    SURVEY OF MIXED INFECTIONS OF FISH-BORNE TREMATODES IN PINYUAN COUNTY AND DNA(RAPD)ANALYSIS

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    目的 调查广东省平远县棘隙吸虫及其他鱼源性吸虫混合感染情况。方法 对鱼类宿主取鱼鳃和鱼肉等组织 ,镜检囊蚴 ;用水洗过筛沉淀法粪检虫卵 ,部分虫卵阳性动物解剖检查。采用DNA -RAPD技术 ,比较福建棘隙吸虫广东株与福建株。结果 查出华支睾吸虫 (Clonorchissinensis)、东方次睾吸虫 (Metorchisorientalis)、福建棘隙吸虫 (Echinochasmusfujianensis)、日本棘隙吸虫 (E japonicus)、抱茎棘隙吸虫 (E perfoliatus)和钩棘单睾吸虫 (Haplorchispumilio) 6种。第二中间宿主为麦穗鱼等 11种 ,感染率 48 3% (182 / 377) ,有 92 4%的阳性鱼混合感染 2种以上吸虫囊蚴。保虫宿主狗、猫感染率 79 2 % (19/ 2 4) ,每只阳性动物均有 2种以上吸虫混合感染。 15个引物在福建棘隙吸虫广东株与福建株两者共获DNA片段 185个 ,共享度 (F) =0 984,遗传距离 (D) =0 0 16。结论 当地为人兽共患的多种鱼源性吸虫混合感染区。形态学观察和分子生物学检测结果相印证 ,福建棘隙吸虫广东株与福建棘隙吸虫福建株为同一虫种。Aim To seek the possible existence of mixed infections of Echinochasmus fujianensis and other fish-borne tremtodes in Pinyuan county,Guangdong.Methods Metacercariae of trematodes were detected from gills,muscles and some other tissues of freshwater fish and examintd under microscopy Sedimentation pocedures were used to observe parasite ova in stool Adult worms were obtained from definitive animal hosts upon dissection Experimental animal infection were performed from metacercariae of E fujianensis strains in Fujian and Guangdong,and it's DNA analysis Random amplified Polymorphic DNA(RAPD).Results Six species of trematodes were found,including Clonorchis sinensis,Metorchis orientalis,E fujanensis, E japonicus,E perfoliatus and Haplorchis pumilio Eleven species of freshwater fish comprising Pseudorasbora parve were identified as the second intermediate hosts,with an average positive rate of 48 33%(182/377) The overall mixed infection animal were contracted with 2 or more species Dogs and cats were detected to be reservoir hosts,the total infection rate being 79 2%(19/24).92 4% of infecded fish were contracted with 2 or 6 speies of the metacercariae of trematodes 185 DNA fragments were obtained by 15 primers,F=0 894 and D=0 016 between E fujianensis Guandong and Fujian strain Conclusion There are six species of fish-borne trematodes which may cause infections in human and animal in the regions E fujianensis Guangdong stain and Fujian strain are the same species福建省科技计划基金!资助项目 (No 98-Z - 1 56);; 福建省“百千万人才”人选培养资

    烟草合子离体培养再生可育植株

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    Study on corrosion resistance and chroma of the deposit from sulfate trivalent chromium plating bath

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    以厦门大学研发的XTC-硫酸盐三价铬镀铬工艺进行中试试验,利用扫描电子显微镜(SEM)、能谱仪(EdS)和CM-2600dlAb值测试仪分别对镀层的表面形貌、组分和色度进行表征,考察了电流密度和导电盐浓度对镀层抗腐蚀能力和色度的影响。结果表明,镀件外观均匀一致,色度白亮、略偏黄;镀层形貌平整、致密,为微裂纹结构;当电流密度为3~6A/dM2,导电盐质量浓度为170g/l时,所得镀层能够通过CASS16H测试。A pilot-scale test for XTC-sulfate trivalent chromium electroplating process developed by Xiamen University was carried out.The surface morphology,composition and chroma of the deposit were characterized by scanning electron microscope(SEM),energy-dispersive spectrometer(EDS) and CM-2600d Lab values tester.The effects of current density and concentration of conductive salt on the corrosion resistance and chroma of deposit were studied.The results indicated that the deposit features a uniform,bright and white appearance with a bit yellowish color,as well as a level and compact morphology with a micro-crack structure.The deposit prepared with conductive salt 170 g/L at current density 3-6 A/dm2 can pass 16-h CASS test.福建省产业技术开发项目(闽发改高技[2010]299号);福建省科技计划重点项目(2008H0086

    黄河中游甘肃中部农作物生产技术

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    本书对黄河中游甘肃中部半干旱区农作物生产技术,如品种、耕作制度、轮作制度、肥料及施肥制度、作物病虫害防治等作了系统的论述,并对其中某些技术项目提供了若干改进意见。此外,关于本区作物分布的情况及一般有关气候情况等亦作了叙述。特别是对本区的耕作制、轮作制度进行了详尽的研究,以便做好本区的水土保持工作
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