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论电子政府成功的关键环节 被引量:1
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作者 王志玮 王国忠 《科技情报开发与经济》 2005年第2期243-244,共2页
在电子政府的具体实施中存在一些关键环节,这些环节将直接决定电子政府的成败。而成功的电子政府实践都非常注重这些关键环节的实施,这些关键环节是电子政府战略、电子分组、合作和组织以及第三方咨询。
关键词 电子政府 关键环节 电子分组 第三方咨询
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Interfacial Modification of NiO_(x)by Self-assembled Monolayer for Efficient and Stable Inverted Perovskite Solar Cells 被引量:1
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作者 Xin Yu Yandong Wang +5 位作者 Liufei Li Shantao Zhang Shuang Gao Mao Liang Wen-Hua Zhang Shangfeng Yang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第4期553-562,I0080-I0091,I0095,共23页
NiO_(x)as a hole transport material for inverted perovskite solar cells has received great attention owing to its high transparency,low fabrication temperature,and superior stability.However,the mismatched energy leve... NiO_(x)as a hole transport material for inverted perovskite solar cells has received great attention owing to its high transparency,low fabrication temperature,and superior stability.However,the mismatched energy levels and possible redox reactions at the NiO_(x)/perovskite interface severely limit the performance of NiO_(x) based inverted perovskite solar cells.Herein,we introduce a p-type self-assembled monolayer between NiO_(x)and perovskite layers to modify the interface and block the undesirable redox reaction between perovskite and NiO_(x)The selfassembled monolayer molecules all contain phosphoric acid function groups,which can be anchored onto the NiOr surface and passivate the surface defect.Moreover,the introduction of self-assembled monolayers can regulate the energy level structure of NiO_(x),reduce the interfacial band energy offset,and hence promote the hole transport from perovskite to NiO_(x)layer.Consequently,the device performance is significantly enhanced in terms of both power conversion efficiency and stability. 展开更多
关键词 Perovskite solar cell NiO_(x) Self-assembled monolayer Interfacial engineering Stability
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The potassium storage performance of carbon nanosheets derived from heavy oils
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作者 ZHAO Qing-shan LIU Qin-lian +6 位作者 LI Yi-wen JI Tian YAO Yu-yue ZHAO Yi-kun DENG Wei HU Han WU Ming-bo 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期1003-1014,共12页
As by-products of petroleum refining,heavy oils are characterized by a high carbon content,low cost and great variability,making them competitive precursors for the anodes of potassium ion batteries(PIBs).However,the ... As by-products of petroleum refining,heavy oils are characterized by a high carbon content,low cost and great variability,making them competitive precursors for the anodes of potassium ion batteries(PIBs).However,the relationship between heavy oil composition and potassium storage performance remains unclear.Using heavy oils containing distinct chemical groups as the carbon source,namely fluid catalytic cracking slurry(FCCS),petroleum asphalt(PA)and deoiled asphalt(DOA),three carbon nanosheets(CNS)were prepared through a molten salt method,and used as the anodes for PIBs.The composition of the heavy oil determines the lamellar thicknesses,sp3-C/sp2-C ratio and defect concentration,thereby affecting the potassium storage performance.The high content of aromatic hydrocarbons and moderate amount of heavy component moieties in FCCS produce carbon nanosheets(CNS-FCCS)that have a smaller layer thickness,larger interlayer spacing(0.372 nm),and increased number of folds than in CNS derived from the other three precursors.These features give it faster charge/ion transfer,more potassium storage sites and better reaction kinetics.CNS-FCCS has a remarkable K^(+)storage capacity(248.7 mAh g^(-1) after 100 cycles at 0.1 A g^(-1)),long cycle lifespan(190.8 mAh g^(-1) after 800 cycles at 1.0 A g^(-1))and excellent rate capability,ranking it among the best materials for this application.This work sheds light on the influence of heavy oil composition on carbon structure and electrochemical performance,and provides guidance for the design and development of advanced heavy oil-derived carbon electrodes for PIBs. 展开更多
关键词 Heavy oils Carbon nanosheets Molten salt method Four-component composition Potassium-ion batteries
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对我国地方政府网站建设的思考 被引量:4
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作者 龚俊朋 《情报探索》 2006年第8期56-57,共2页
网站是政府发布信息的重要平台,目前地方政府网站在功能建设方面存在明显的不足。今后应在电子分组、内容导航检索、安全等方面多做有益的探索和努力。
关键词 政府网站 电子分组 信息构建 地方政府 内容导航检索 功能建设 中国
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地方政府网站建设中存在的问题及对策分析 被引量:2
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作者 龚俊朋 《农业图书情报学刊》 2006年第4期12-13,共2页
发布信息、提供服务是政府网站的重要职能,目前政府网站在这些方面的建设却存在明显的不足。政府网站建设应该在加强电子分组,“一站式”服务,网站内容检索、导航、安全等方面多做努力。
关键词 电子分组 信息资源 网站建设
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Microstructure and defect of titanium alloy electron beam deep penetration welded joint 被引量:8
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作者 张秉刚 石铭霄 +1 位作者 陈国庆 冯吉才 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2633-2637,共5页
The microstructure, phase composition and cold shut defect of thick titanium alloy electron beam welded joint were studied. The results showed that the microstructure of weld zone was composed of α′ phase; the heat ... The microstructure, phase composition and cold shut defect of thick titanium alloy electron beam welded joint were studied. The results showed that the microstructure of weld zone was composed of α′ phase; the heat affected zone was divided into fine-grained zone and coarse-grained zone, the microstructure of fine-grained zone was primary α phase + β phase + equiaxed α phase, and the microstructure of coarse-grained zone was primary α phase + acicular α′ phase; the microstructure of base metal zone basically consisted of primary α phase, and a small amount of residual β phase sprinkled. The forming. reason of cold shut was analyzed, and the precaution of cold shut was proposed. 展开更多
关键词 TA15 titanium alloy electron beam welding MICROSTRUCTURE phase composition cold shut defect weld zone heataffected zone
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Synthesis of PE with Broad MWD Catalyzed by Supported Ziegler-Natta Catalyst Consisting of Cycloalkoxy Silane as IED
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作者 Yu Mengshan Nie Yanpei +4 位作者 Zhou Lu Yi Jianjun Huang Qigu Gao Kejing Yang Wantai 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2014年第2期91-96,共6页
Two kinds of cycloalkoxy silane compounds were synthesized and used as the internal electron donors (IEDs) of supported Ziegler-Natta catalyst for ethylene polymerization to produce polyethylene with broader molecul... Two kinds of cycloalkoxy silane compounds were synthesized and used as the internal electron donors (IEDs) of supported Ziegler-Natta catalyst for ethylene polymerization to produce polyethylene with broader molecular weight distribution (MWD), The effect of the structure and the amount of these IEDs on the polymerization performance was in- vestigated. The results implied that the molecular weight distribution of the obtained polyethylene could be adjusted by the incorporation of IEDs. SEM result showed that the morphology of catalyst particle was spherical and uniform in size distribution. The titanium content of these catalysts was higher, the active TiCl4 species were easily anchored on the support than that without adding IED, which was determined by ICE The GPC result confirmed that the polyethylene with broader molecular weight distribution in the range of from 23.4 to 25.6 was obtained using triethoxy-(-cyclopentyloxy)-silane (ED1) and triethoxy-(-cyclohexyloxyl)- silane (ED2) as the internal electron donors. 展开更多
关键词 supported Ziegler-Natta catalyst POLYETHYLENE broader molecular weight distribution electron donor
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Comparison of pore characteristics in the coal and shale reservoirs of Taiyuan Formation, Qinshui Basin, China 被引量:30
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作者 Yu Liu Yanming Zhu 《International Journal of Coal Science & Technology》 EI 2016年第3期330-338,共9页
Coal and shale are both unconventional gas reservoirs. Comparison of pore characteristics in shale and coal would help understand organic pore structure in shale and investigate co-exploration of shale gas and coalbed... Coal and shale are both unconventional gas reservoirs. Comparison of pore characteristics in shale and coal would help understand organic pore structure in shale and investigate co-exploration of shale gas and coalbed methane in coal bearing strata. In this study, five shale samples and three coal samples of Taiyuan Formation were collected from Qinshui Basin, China. High pressure mercury injection, scanning electronic microscopy, and fractal theory have been used to compare pore characteristics in shale and coal. The results show that pore volumes in coal are much larger than that in shale, especially pores 3-100 nm. In coal, there are many semi-closed pores in micro pores (〈10 nm) and transition pores (10-100 nm). On the contrary, micro pores and transition pores are mainly with open pores in shale. The fractal curves show that pores larger than 65 nm in coal and shale reservoir both have obvious self-similarity and the fractal dimension values in shale and coal are similar. But the fractal characteristics of pores smaller than 65 nm in shale reservoir are quite different from that in coal. 展开更多
关键词 COMPARISON COAL SHALE Organic pores FRACTAL
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Two-Component Description for Relativistic Fermions
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作者 CHEN Yu-Qi SANG Wen-Long YANG Lan-Fei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第6期1095-1100,共6页
We propose a two-component form to describe massive relativistic fermions in gauge theories. Relations between the Green's functions in this form and those in the conventional four-component form are derived. It is s... We propose a two-component form to describe massive relativistic fermions in gauge theories. Relations between the Green's functions in this form and those in the conventional four-component form are derived. It is shown that the S-matrix elements in both forms are exactly the same. The description of the fermion in the new form simplifies significantly the γ-matrix algebra in the four-component form. In particular, in perturbative calculations the propagator of the fermion is a scalar function. As examples, we use this form to reproduce the relativistic spectrum of hydrodron atom, the S-matrix of e+e-→μ+μ- and QED one-loop vacuum polarization of photon. 展开更多
关键词 FERMIONS two-component description Dirac equation
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Controlled Release of the Indomethacin Microencapsulation Based on Layer-by-layer Assembly by Polyelectrolyte Multilayers
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作者 CHEN You-fang LIN Xian-fu 《Chinese Journal of Biomedical Engineering(English Edition)》 2007年第1期8-13,共6页
Indomethacin has been encapsulated with polyelectrolyte multilayers for controlled release. Gelatin and alginate were alternatively deposited on indomethacin microcrystals. The released amount of indomethacin from coa... Indomethacin has been encapsulated with polyelectrolyte multilayers for controlled release. Gelatin and alginate were alternatively deposited on indomethacin microcrystals. The released amount of indomethacin from coated microcrystals in pH6. 8 phosphate buffer solution (PBS) was measured with a UV spectrophometer. The polyelectrolyte multilayer capsule thickness was proved to control the release rate. The effects of osmotic pressure existed during the release process of indomethacin from microcapsules coated by (gelatin/alginate) 4. 展开更多
关键词 INDOMETHACIN ENCAPSULATED Controlled release SELF-ASSEMBLY POLYELECTROLYTE
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Synergistic promotion of HER and OER by alloying ternary Zn‐Co‐Ni nanoparticles in N‐doped carbon interfacial structures
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作者 Limei Lu Yihe Zhang +5 位作者 Zhensheng Chen Feng Feng Kaixuan Teng Shuting Zhang Jialin Zhuang Qi An 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第5期1316-1323,共8页
Catalytic water splitting potentially reduce the consumption of fossil fuels and has received intense research attention.Synergy effects in multi‐element transition metal‐based water splitting catalysts have evoked ... Catalytic water splitting potentially reduce the consumption of fossil fuels and has received intense research attention.Synergy effects in multi‐element transition metal‐based water splitting catalysts have evoked special interests.Studies on catalysts in interfacial structures are especially meaningful due to their pertinence in applications.In this study,we report the synergy effects in promoting catalytic power in the ternary transition metal Zn,Co,Ni alloy nanoparticles that embeds in the carbonized Ppy/CNT multilayered matrix.By comparison with a series of binary or single metal counterparts,the mechanism under the synergy effects are elucidated.Experimental and DFT calculation results indicate that the ternary transition metal catalysts in the N‐doped carbon matrix present special electronic structure,which benefits the reversible transition‐state adsorption in HER and OER and render the catalysts high conductivity in room temperature.We expect our findings inspire further development of efficient transition metal HER and OER catalysts. 展开更多
关键词 Water splitting Hydrogen evolution reaction Oxygen evolution reaction Diversity of elements Electron modification
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Historical Development in Soil Micromorphological Imaging 被引量:2
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作者 A.R.Mermut 《Journal of Mountain Science》 SCIE CSCD 2009年第2期107-112,共6页
The book "micropedolog" by Kubieana and a large number of publications has induced many people to practice soil micromorphology. Quantification of the soil fabric and its components was a major challenge. The use of... The book "micropedolog" by Kubieana and a large number of publications has induced many people to practice soil micromorphology. Quantification of the soil fabric and its components was a major challenge. The use of the image analyses in soil science was a breakthrough. Attempts to make soil thin sections go back to the beginning of the 2oth century. Microscopic techniques and recently high resolution electron microscope and use of computer assisted imaging techniques enabled the in vitro study of soils in three dimensional levels. It is now possible to store and process massive amounts of data. Micro- morphological concepts and techniques are applied in paleopedological, ecological, and archaeological studies. The aim of this work was to examine soil micromorphological imaging in historical perspective. 展开更多
关键词 Soil micromorphology quantification imaging techniques HISTORY
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Different Carbon Fractions in Soils and Their Relationship with Trace Elements Content
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作者 Lubica Pospisilova Petr Skarpa Marie Konecna 《Journal of Life Sciences》 2011年第4期316-321,共6页
Luvisols, Stagnogleys and Cambisols, although less fertile, are used intensively for mixed farming, grazing and as forestland. Therefore we aimed our study at determination of total organic carbon (TOC) content, hum... Luvisols, Stagnogleys and Cambisols, although less fertile, are used intensively for mixed farming, grazing and as forestland. Therefore we aimed our study at determination of total organic carbon (TOC) content, humic substances (HS) content, humic acids (HA) content, fulvic acids (FA), hot water extractable carbon (Chw) content and content total and labile trace elements content. Humic substances quality was assessed by HA/FA ratio and by coloured indexes measured in ultraviolet and visible UV-VIS spectral range. The total and labile contents of Zn, Cd, Cu, Co, Pb, Mo and Se were determined by flame or electro-thermal atomic absorption spectrometry after extraction of the soil samples in the aqua regia (total content) and in the solution of 0.01 M CaCI2. Total and labile trace elements content was correlated with determined carbon fractions and soil reaction. Results showed that studied soils content low amount of TOC and had low quality of humic substances. HA/FA ratio was less than 1 and colour indexes were higher than 4. All determined carbon fractions correlated with labile form of Zn and Cd. Correlation between soil reaction and total zinc content was found. Significant effect of humic substances content on to water-soluble forms of heavy metals was detected. 展开更多
关键词 Humic acids fulvic acids hot water extractable carbon humus fractionation labile trace elements total trace elements.
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Blended Learning and Applying New Tools and Services of E-Learning Support
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作者 Veselinka Ivanova Nedeva Snejana Boycheva Dineva 《Computer Technology and Application》 2012年第7期471-476,共6页
The strengths and weaknesses of different online technologies and learning methods have been examined by combining the blended learning program with practical work on institutional e-learning projects. There are diffe... The strengths and weaknesses of different online technologies and learning methods have been examined by combining the blended learning program with practical work on institutional e-learning projects. There are differences between the traditional e-learning system and the new E-Learning 2.0 training. At present time, the new technologies provided by Web 2.0 better correspond to the needs of both students and teaching staff. The new Web 2.0 allows the "promoting of individual creativity", together with the "use of collective intelligence". A comparison of the two development stages of the e-learning tools has been completed and the advantages of E-Learning 2.0 are shown. The main components of Web 2.0 are provided and the use ofwiki as an up-to-date collaboration tool for on-line teamwork is shown. 展开更多
关键词 E-Learning 1.0 E-Learning 2.0 blended learning Web 2.0 applications wiki activities.
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Numerical Analysis of a Gravity Substructure for 5 MW Offshore Wind Turbines Due to Soil Conditions
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作者 Min-Su Park Youn-Ju Jeong Young-Jun You 《Journal of Energy and Power Engineering》 2016年第3期150-158,共9页
In order to increase the gross generation of wind turbines, the size of a tower and a rotor-nacelle becomes larger. In other words, the substructure for offshore wind turbines is strongly influenced by the effect of w... In order to increase the gross generation of wind turbines, the size of a tower and a rotor-nacelle becomes larger. In other words, the substructure for offshore wind turbines is strongly influenced by the effect of wave forces as the size of substructure increases. In addition, since a large offshore wind turbine has a heavy dead load, the reaction forces on the substructure become severe, thus very firm foundations should be required. Therefore, the dynamic soil-structure interaction has to be fully considered and the wave forces acting on substructure accurately calculated. In the present study, ANSYS AQWA is used to evaluate the wave forces. Moreover, the substructure method is applied to evaluate the effect of soil-structure interaction. Using the wave forces and the stiffness and damping matrices obtained from this study, the structural analysis of the gravity substructure is carried out through ANSYS mechanical. The structural behaviors of the strength and deformation are evaluated to investigate an ultimate structural safety and serviceability of gravity substructure for various soil conditions. Also, the modal analysis is carried out to investigate the resonance between the wind turbine and the gravity substructure. 展开更多
关键词 Offshore wind energy gravity substructure suction bucket foundation substructure method structural analysis.
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浅谈机载平显设备的使用与维护
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作者 蒋江涛 武立朋 《航空维修与工程》 2020年第5期89-91,共3页
结合工作实践,对机载平显设备的正确使用、日常检查和维护、常见故障的隔离与定位方法等方面进行介绍,为从事机载平显设备维护、维修的人员提供参考。
关键词 平显 电子分组 光学分组
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STIM1 and Orai1:novel targets for vascular diseases? 被引量:6
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作者 Mohamed TREBAK 《Science China(Life Sciences)》 SCIE CAS 2011年第8期780-785,共6页
The past five years have witnessed the discovery of the endoplasmic reticulum calcium(Ca2+) sensor STIM1 and the plasma membrane Ca2+channel Orai1 as the bona fide molecular components of the store-operated Ca2+ entry... The past five years have witnessed the discovery of the endoplasmic reticulum calcium(Ca2+) sensor STIM1 and the plasma membrane Ca2+channel Orai1 as the bona fide molecular components of the store-operated Ca2+ entry(SOCE) and the Ca2+ release-activated Ca2+current(I CRAC) .It has been known for two decades that SOCE and ICRAC are required for lymphocyte activation as evidenced by severe immunodeficient phenotypes in patients lacking ICRAC.In recent years however,studies have uncovered expression of STIM1 and Orai1 proteins in various tissues and described additional roles for these proteins in physiological functions and pathophysiological conditions.Here,we will summarize novel findings pertaining to the role of STIM1 and Orai1 in the vascular system and discuss their potential use as targets in the therapy of vascular disease. 展开更多
关键词 calcium signaling calcium channels Orail STIM1 CRAC channels vascular disease
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Forming electron traps deactivates self-assembled crystalline organic nanosheets toward photocatalytic overall water splitting 被引量:5
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作者 Lei Wang Jia Liu +4 位作者 Haiyun Wang Hao Cheng Xiaojun Wu Qun Zhang Hangxun Xu 《Science Bulletin》 SCIE EI CSCD 2021年第3期265-274,M0004,共11页
Most biological photoredox reactions occur in sophisticated molecular assemblies consisting of highly organized light-harvesting moieties and catalytic centers.Mimicking these prototypes by creating supramolecular ass... Most biological photoredox reactions occur in sophisticated molecular assemblies consisting of highly organized light-harvesting moieties and catalytic centers.Mimicking these prototypes by creating supramolecular assemblies could be a potentially viable approach toward artificial photosynthesis.Although self-assembled organic materials are known to carry out water splitting reactions,developing self-assembled organic materials for photocatalytic overall water splitting still remains a critical challenge.Herein,we first demonstrate that crystalline organic nanosheets assembled from linear oligo(phenylene butadiynylene)(OPB)are able to catalyze overall water splitting under visible light irradiation.Further investigations reveal that the photocatalytic activity of self-assembled organic structures is closely related to the crystalline structure along with the corresponding electronic structure.Structural disorders in OPB nanosheets and extrinsic factors such as adsorbed water molecules will induce the formation of electron traps which can make the OPB nanosheets thermodynamically unfavorable for photocatalytic overall water splitting.The deactivation mechanism unveiled in this study provides crucial insights into the assembling of artificial organic materials for future solar-to-chemical energy conversion. 展开更多
关键词 Self-assembly Water splitting PHOTOCATALYSIS Conjugated polymers DEACTIVATION
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Nanowire-based transparent conductors for flexible electronics and optoelectronics 被引量:9
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作者 Jie Xue Jizhong Song +3 位作者 Yuhui Dong Leimeng Xu Jianhai Li Haibo Zeng 《Science Bulletin》 SCIE EI CAS CSCD 2017年第2期143-156,共14页
As the necessary components for various modern electronic and optoelectronic devices, novel transparent electrodes(TEs) with the low cost, abundance features, and comparable performance of indium tin oxide(ITO) are in... As the necessary components for various modern electronic and optoelectronic devices, novel transparent electrodes(TEs) with the low cost, abundance features, and comparable performance of indium tin oxide(ITO) are inquired materials. Metal nanowires(NWs) with the excellent photoelectric properties as next-generation TE candidates have widely applications in smart optoelectronic devices such as electronic skins, wearable electronics, robotic skins, flexible and stretchable displays. This review describes the synthetic strategies for the preparation of metal NWs, the assemble process for metal NW films,and the practical aspects of metal NW films with the desired properties in various low-cost, flexible,and solution-based photoelectric devices. 展开更多
关键词 Metal nanowires Transparent electrodes Solution-based process Light-emitting diodes Touch screens Solar cells
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Stable ZnO/ionic liquid hybrid materials: novel dual-responsive superhydrophobic layers to light and anions 被引量:2
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作者 LI HongLiang XIN BingWei +1 位作者 FENG Lei HAO JingCheng 《Science China Chemistry》 SCIE EI CAS 2014年第7期1002-1009,共8页
Novel dual-responsive superhydrophobic hybrid materials, ZnO/SAMs (self-assembled monolayers) of ionic liquids (ILs) with different counter-anions (I^-, BF4^-, PF6^- and Tf2N^-), were synthesized and characteriz... Novel dual-responsive superhydrophobic hybrid materials, ZnO/SAMs (self-assembled monolayers) of ionic liquids (ILs) with different counter-anions (I^-, BF4^-, PF6^- and Tf2N^-), were synthesized and characterized. ZnO nanoparticles were first deposited on glass surfaces to produce roughness. Next, SAMs of fluorinated-alkyl-3-(3-triethoxysilylpropyl)-4,5-dihydro-imidazoliumiodide (abb. [C8Ftespim]I) were grafted onto these surfaces via -Si-O- covalent bonds using self-assembly technique. The I- ion could be subsequently exchanged with BF4, PF6-or Tf2N- through a simple aqueous anion-exchange reaction. The ZnO/ILs hybrid layers were characterized by atomic-force microscopy (AFM), scanning-electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Their wettability was estimated through the measurements of static and dynamic contact angles (CAs). Compared to corresponding films of ZnO/[CsFtespim]I with CAs 140.7° ±2.0°, films of ZnO/[CsFtespim]PF6 and ZnO/[CsFtespim]Tf2N showed CAs with 154.0° ± 2.0° and 152.0° ± 2.0°, respectively that remained for a long time. This result suggests that anion-exchange can afford superhydrophobic materials. In addition, the wettability of ZnO/[CsFtespim]X hybrid layers can be reversibly switched by altering ultraviolet (UV) irradiation and dark storage, which shows a photo-induced reversible switch of wettability. The synergistic action of ZnO nanoparticles and SAMs of ILs produced light-anion dual-responsive superhydrophobic materials with ideal stability. 展开更多
关键词 ZnO/IL hybrid materials dual-responsive surface SAMs of ionic liquid wettability ZnO nanoparticles
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