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China's study on coal mining beneath surface buildings——state-of-the-art and developing trend
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作者 TENG Yong-hai~(1, 2), WANG Jin-zhuang~1 (1. China Institute of Mining Technology Beijing Campus, Beijing 100083, China 2. China Coal Research Institute Tangshan Branch, Tangshan 063012, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期13-16,共4页
Extensive coal deposits are sterilized beneath surface buildings in China. The paper elaborates on the present status of the study on mining beneath surface buildings from several aspects involving the techniques for ... Extensive coal deposits are sterilized beneath surface buildings in China. The paper elaborates on the present status of the study on mining beneath surface buildings from several aspects involving the techniques for reducing ground subsidence and deformation and the measures for protecting buildings. Following that, it is pointed out that, in the future, more efforts should be directed forwards the following aspects: the laws governing the ground movement; the techniques for constructing anti-deformation buildings; coal-bed gasification and protection of buildings; grouting of the overlying strata with bed separation phenomena; and the method for evaluating the stability of the ground above a worked-out area. 展开更多
关键词 MINING BENEATH buildings state-OF-THE-ART of STUDY developing TREND
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Preparation, Structure and Properties of 3D Supramolecular Architecture, on the Basis of Hydrogen Bonds and π-π Stacking Between 2D Layers, with Windmill Building Blocks
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作者 YU Li-qiong HUANG Ru-dan CHI Ying-nan HU Chang-wen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第3期251-254,共4页
A novel three-dimensional(3D) supramolecular architecture, {[Nd(OH-BDC)(OH-HBDC)(H2O)2]·2HaO)n(1) (OH-H2BDC=5-hydroxyisophthalic acid), which was formed through hydrogen bonds and π-π stacking betw... A novel three-dimensional(3D) supramolecular architecture, {[Nd(OH-BDC)(OH-HBDC)(H2O)2]·2HaO)n(1) (OH-H2BDC=5-hydroxyisophthalic acid), which was formed through hydrogen bonds and π-π stacking between two-dimensional(2D) layers, was hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Windmill building blocks, which consist of two nine-coordinated metal centers and four OH-H2BDC groups are connected through two carboxyl groups, to lead to a one-dimensional infinite inorganic chain(… M--O--C--O--M…) along the [100] direction. An observed intense blue luminescence with an emission band peaked at 390 nm for compound 1 may results from ligand-to-metal charge transfer(LMCT). Variable-temperature magnetic susceptibility of compound 1 was investigated and the value was deviated from the Curie-Weiss law. 展开更多
关键词 building block π-π stacking Hydrogen bond Luminescence MAGNETISM
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1989 12 Good Building Material Products Won State Awards in China
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作者 based on China Building Materials News by our staff reporter Shao De 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1990年第1期67-67,共1页
In 1989, there were 12 different building ma-terial products winning state awards for theirgood quality, among which two got gold medals andten got silver medals.
关键词 Good building Material Products Won state Awards in China
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Running States of China's Iron & Steel,Nonferrous,and Building Materials Industries in 2012
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《China's Refractories》 CAS 2013年第1期11-11,共1页
Iron & Steel Industry China's outputs of crude steel, steel products, coke and ferrous alloys in 2012 were 716.54 million tons (up 3.1% YOY), 051.86 million tons (up 7.7% YOY), 443.23 million tons (up 5.2% YOY... Iron & Steel Industry China's outputs of crude steel, steel products, coke and ferrous alloys in 2012 were 716.54 million tons (up 3.1% YOY), 051.86 million tons (up 7.7% YOY), 443.23 million tons (up 5.2% YOY) and 31.29 million tons (up 15% YOY), 展开更多
关键词 Running states of China’s Iron Steel Nonferrous and building Materials Industries in 2012
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Running State of China's Building Materials Industry in 2013
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《China's Refractories》 CAS 2014年第1期42-42,共1页
In 2013, China's outputs of cement and flat glass were 2. 414 billion tons and 778.98 million weight cases, increasing by 9.6% and 11.2% YOY, respectively.
关键词 Running state of China’s building Materials Industry in 2013
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Model Reduction Methods for High-Rise Buildings with Active Mass Damper Control Systems
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作者 Jun Teng Hou-Bing Xing Cheng-Yin Liu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第6期37-45,共9页
To improve the performance of an active mass damper control system,the controller should be designed based on a reduced-order model. An improved method based on balanced truncation method was proposed to reduce the di... To improve the performance of an active mass damper control system,the controller should be designed based on a reduced-order model. An improved method based on balanced truncation method was proposed to reduce the dimension of high-rise buildings,and was compared with other widely used reduction methods by using a framework with ten floors. This optimized method has improvement of reduction process and choice of the order. Based on the reduced-order model obtained by the improved method and pole-assignment algorithm,a controller was designed. Finally,a comparative analysis of structural responses,transfer functions,and poles was conducted on an actual high-rise building. The results show the effectiveness of the improved method. 展开更多
关键词 high-rise building active mass damper model reduction controller designCLC number:TU352 Document code:AArticle ID:1005-9113(2013)06-0037-09
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Net Present Value Method: A Method Recommended by ISO 15686-5 for Economic Evaluation of Building Life Cycle Costs
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作者 Hao Xie Qiao Cui Yang Li 《World Journal of Engineering and Technology》 2022年第2期224-229,共6页
The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This stu... The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This study explains the concept and method of PV, and then provides an explanation of the concept and method of NPV, and points out the limitations in the practical application of the method. 展开更多
关键词 NPV ISO 15686-5 building Life Cycle Cost Economic Evaluation
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Key State Projects in the Building Materials Industry
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《China's Foreign Trade》 1998年第2期16-16,共1页
关键词 Key state Projects in the building Materials Industry
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基于行为安全“2-4”模型理论的建筑施工事故行为原因分析 被引量:2
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作者 孙世梅 孙祖航 +1 位作者 冯子阳 傅贵 《中国安全科学学报》 CAS CSCD 北大核心 2023年第11期30-37,共8页
为深入探究我国建筑施工行业事故发生特点,运用行为安全“2-4”模型理论,从人的不安全行为、物的不安全状态、安全知识、安全意识、安全习惯、安全管理、安全文化等方面着手,全面、系统地分析建筑施工中5大典型伤害事故(高处坠落事故、... 为深入探究我国建筑施工行业事故发生特点,运用行为安全“2-4”模型理论,从人的不安全行为、物的不安全状态、安全知识、安全意识、安全习惯、安全管理、安全文化等方面着手,全面、系统地分析建筑施工中5大典型伤害事故(高处坠落事故、物体打击事故、机械伤害事故、坍塌事故、触电事故)发生的原因;根据事故发生的权重对不同阶段原因的发生率和影响度进行重要度计算。结果表明:导致建筑施工事故发生的主要原因是个人行为,即不按规程佩戴个人防护用品、未意识到安全培训的重要性、安全管理制度欠缺、忽视安全培训需求;未按规章进行作业、设备故障、缺少个人防护用品使用知识、安全检查制度欠缺、安全的重要度等为重要原因。安全监管人员在未来工作中应着重应对主要原因和重要原因,事先预防以保障企业安全生产。 展开更多
关键词 行为安全 “2-4”模型 建筑施工事故 行为原因 物态原因
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超大规模国家现代化何以可能?--以国家动员能力为分析中心 被引量:2
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作者 殷冬水 《探索》 北大核心 2023年第5期66-79,共14页
理解中国现代化取得的成就,离不开现代化的政治维度,即政治现代化。这不仅是因为政治现代化是中国现代化的一项重要内容,也是因为政治现代化是中国现代化有效推进的一个重要条件。现代化的发展需要国家的引领,需要一个强有力国家政权体... 理解中国现代化取得的成就,离不开现代化的政治维度,即政治现代化。这不仅是因为政治现代化是中国现代化的一项重要内容,也是因为政治现代化是中国现代化有效推进的一个重要条件。现代化的发展需要国家的引领,需要一个强有力国家政权体系的推动,尤其是需要不断动员人民群众的力量。正是因为有了强有力的国家政权体系的组织、规划、统筹、动员,中国现代化才得以在特定的时空中展开,在适应复杂环境中变革发展。从政治学视角看,中国现代化取得的成就,很大程度上归功于中国共产党持续不断地加强国家建设,缔造出一个具有强大动员能力的新型现代国家。新型现代国家既是中国现代化发展的关键构成要素,也是推动中国现代化发展的主导力量。新型现代国家通过有效的思想动员,将现代意识植入社会之中,实现社会的深刻变革,培养社会成员对现代化的认知与认同,为现代化发展提供强大的精神动力;通过广泛的参与动员,团结一切可以团结的力量,形成了齐心协力推动现代化建设的局面;通过广泛的资源动员,有效汇集和调配现代化所需要的资源。实践业已表明,中国共产党领导人民所进行的现代化建设,既改变了中国人民的集体命运,也创造了一种新型的人类文明。 展开更多
关键词 中国式现代化 国家构建 新型现代国家 国家动员能力
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Seismic hazard level reduction for existing buildings considering remaining building lifespans 被引量:1
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作者 Ji-Hun Park 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第3期649-661,共13页
Seismic hazard levels lower than those for design of new buildings have been permitted for seismic evaluation and retrofi t of existing buildings due to the relatively short remaining lifespans. The seismic hazard red... Seismic hazard levels lower than those for design of new buildings have been permitted for seismic evaluation and retrofi t of existing buildings due to the relatively short remaining lifespans. The seismic hazard reduction enables costeff ective seismic evaluation and retrofi t of existing buildings with limited structural capacity. The current study proposes seismic hazard reduction factors for Korea, one of low to moderate seismicity regions. The seismic hazard reduction factors are based on equal probabilities of non-exceedance within diff erent remaining building lifespans. A validation procedure is proposed to investigate equality of seismic risk in terms of ductility-based limit states using seismic fragility assessment of nonlinear SDOF systems, of which retrofi t demands are determined by the displacement coeffi cient method of ASCE 41-13 for diff erent target remaining building lifespans and corresponding reduced design earthquakes. Validation result shows that the use of seismic hazard reduction factors can be permitted in conjunction with appropriate lower bounds of the remaining building lifespans. 展开更多
关键词 SEISMIC HAZARD level existing building REMAINING building LIFESPAN probability of LIMIT state
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Effect of varying normal stress on stability and dynamic motion of a spring-slider system with rate- and state-dependent friction 被引量:2
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作者 Changrong He Teng-fong Wong 《Earthquake Science》 2014年第6期577-587,共11页
Incorporating rate and state friction laws, stability of linearly stable (i.e., with stiffness greater than the critical value) spring-slider systems subjected to triggering perturbations was analyzed under variable... Incorporating rate and state friction laws, stability of linearly stable (i.e., with stiffness greater than the critical value) spring-slider systems subjected to triggering perturbations was analyzed under variable normal stress condition, and comparison was made between our results and that of fixed normal stress cases revealed in previous studies. For systems associated with the slip law, the critical mag- nitude of rate steps for triggering unstable slips are found to have a similar pattern to the fixed normal stress case, and the critical velocity steps scale with a/(b - a) when k = kcr for both cases. The rate-step boundaries for the variable normal stress cases are revealed to be lower than the fixed normal stress case by 7 %-16 % for a relatively large ct = 0.56 with (b - a)/a ranging from 0.25 to 1, indicating easier triggering under the variable normal stress condition with rate steps. The difference between fixed and variable normal stress cases decreases when the α value is smaller. In the same slip- law-type systems, critical displacements to trigger instability are revealed to be little affected by the variable normal stress condition. When k 〉 kcr(V,), a spring-slider system with the slowness law is much more stable than with the slip law,suggesting that the slowness law fits experimental data better when a single state variable is adopted. In stick-slip motions, the variable normal stress case has larger stress drops than the constant normal stress case. The variable normal stress has little effect on the range of slip velocity in systems associated with the slowness law, whereas systems associated with the slip law have a slowest slip velocity immensely smaller than the fixed normal stress case, by ~ 10 orders of magnitude. 展开更多
关键词 Rate and state friction - Stability Variablenormal stress Stick-slip motion
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Solid-state synthesis of Sr-and Co-doped LaMnO_3 perovskites 被引量:1
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作者 马文会 谢刚 +1 位作者 陈书荣 崔衡 《中国有色金属学会会刊:英文版》 CSCD 2001年第6期904-907,共4页
The synthesis process for La 1- x Sr x Mn 1- y Co y O 3- δ ( x = 0.2, 0.3; y = 0.2, 0.8, designated as LSMC below) perovskite oxides prepared by solid state reaction was investigated using DSC/TG, XRD, EPMA and parti... The synthesis process for La 1- x Sr x Mn 1- y Co y O 3- δ ( x = 0.2, 0.3; y = 0.2, 0.8, designated as LSMC below) perovskite oxides prepared by solid state reaction was investigated using DSC/TG, XRD, EPMA and particle size analysis methods. It was found that LSMCs were all of single phase and the synthesis process might be divided into three stages: the decomposition of reactants, the formation of LaMn(Co)O 3 based oxides, and the formation of LSMC solid solution. Typical average and the peak value of particle size, and the specific surface area are 14.65?μm, 16.4?μm and 1.38?m 2/mL, respectively, for mixed reactants and are 23.81?μm, 32.11?μm and 0.5?m 2/mL, respectively, for powder synthesized at 1?200?℃ for 8?h in air. 展开更多
关键词 solid state reaction synthesis La 1- x Sr x Mn 1- y Co y O 3- δ perovskite intermediate temperature SOFCs
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“生活国家”的构建:中国国家建设的历史进程与基本经验--以乡村生活治理为讨论中心 被引量:9
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作者 田先红 吕德文 《社会科学》 北大核心 2023年第4期152-166,12,共16页
“生活国家”的构建是中国国家建设的重要内容。干预和保障民众生活的主题,贯穿于从传统中国到新中国成立以来的整个国家建设过程。传统中国和民国时期,因国家能力较弱、干预方式不当等原因,国家的乡村生活治理成效甚微。中国共产党领... “生活国家”的构建是中国国家建设的重要内容。干预和保障民众生活的主题,贯穿于从传统中国到新中国成立以来的整个国家建设过程。传统中国和民国时期,因国家能力较弱、干预方式不当等原因,国家的乡村生活治理成效甚微。中国共产党领导新中国以实现全体人民自由全面发展为己任,并将农村农民作为保障和改善民生之重点,构建了系统性的乡村生活治理模式,通过理性化的顶层设计、强大的组织动员能力、健全的利益分配机制以及充满韧性的调适能力,不断推进乡村生活治理进程,取得了举世瞩目的成效,积累了宝贵经验。“生活国家”构建的研究路径,将生活治理置于中国国家形成与建设的大历史视野中去考察,有利于拓展生活治理的研究视野,丰富现代国家构建的理论知识体系。 展开更多
关键词 生活国家 国家建设 生活治理 系统治理 中国共产党
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Analysis of the Variations of Body Build of Middle-and Old-aged and Research on the Prototype
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作者 李兴刚 沈卫勤 《Journal of China Textile University(English Edition)》 EI CAS 2000年第4期61-65,共5页
The characteristics of body build of middle - and old -aged women and its rule of variations as well as the basic sizes of various parts are discussed. All these are based on the body measurements of this age group, a... The characteristics of body build of middle - and old -aged women and its rule of variations as well as the basic sizes of various parts are discussed. All these are based on the body measurements of this age group, and also on the statistical studies of the measurement data. By setting the regression equation, the calculating formulae of various control parts are obtained, thus establishing the prototype of this age group for women. 展开更多
关键词 MIDDLE - and old - aged characteristics of BODY build APPAREL sizes and types PROTOTYPE
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Elaborately tuning the electronic structure of single-atom nickel sites using nickel nanoparticles to markedly enhance the electrochemical reduction of nitrate into ammonia 被引量:1
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作者 Zichao Xi Jiaqian Wang +4 位作者 Baocang Liu Xuan Xu Peng Jing Rui Gao Jun Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期32-42,I0003,共12页
The electrochemical reduction of nitrate to ammonia(NH3) can be used to recycle nitrogen and offers a decarbonized route for sustainable NH3production,but requires efficient electrocatalysts.Herein,we have rationally ... The electrochemical reduction of nitrate to ammonia(NH3) can be used to recycle nitrogen and offers a decarbonized route for sustainable NH3production,but requires efficient electrocatalysts.Herein,we have rationally designed and fabricated a novel self-supported electrocatalyst comprised of Ni nanoparticles(NiNPs) embedded in Ni single atoms(NiSAs) anchored to nitrogen-doped carbon nanotubes grown on carbon cloth(NiNPs@NiSAs-NCNTs/CC) used for an efficient nitrate reduction reaction(NO3-RR) to produce NH_(3).The electrocatalyst can attain a maximum NH3yield rate of 27.67±1.16 mgNH3h^(-1)cm^(-2)at-1.4 V vs.reversible hydrogen electrode(RHE) and nearly 100% Faradic efficiency in the range of-1.2--1.4 V vs.RHE in a neutral medium,outperforming the previously reported Ni-based catalysts.Our experimental analysis and theoretical calculations have demonstrated that the moderate electrondeficient state of NiSAsregulated by NiNPsnot only facilitates the enrichment of NO_(3)^(-),but also benefits the formation of NO3*and decrease in the energy barrier of the rate-limiting step,thus resulting in the enhanced NO3-RR performance. 展开更多
关键词 Nitratereductionreaction Moderateelectron-deficient state Self-supported ELECTROCATALYST Enrichmentof NO_(3)^(-) Theoreticalcalculations
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Modeling of Solid-state Polycondensation of Poly (ethylene terephthalate)
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作者 邓德纯 王燕萍 +2 位作者 蒋歧康 唐志廉 黄南薰 《Journal of China Textile University(English Edition)》 EI CAS 2000年第4期30-33,共4页
A mathematical model has been developed to handle the reactions in Poly(ethylene terephthalate) (PET) undergoing polycondensation reactions in the solid state. The effect of temperature on chain mobility was considere... A mathematical model has been developed to handle the reactions in Poly(ethylene terephthalate) (PET) undergoing polycondensation reactions in the solid state. The effect of temperature on chain mobility was considered to estimate the rate constants of chemical reactions. The polymer crystalline fraction is modeled as containing only repeat units, thus concentrating end groups and conden-sates in the amorphous fraction. This model is compared with PET reaction data with good results. 展开更多
关键词 SOLID - state POLYMERIZATION PET POLYMER REACTION engineering.
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Equation of State of Nuclear Matter in Chiral σ-ω Model
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作者 CHENWei DONGDong-Qiao +2 位作者 WENDe-Hua LIUGuo-Tao LIULiang-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第6期925-928,共4页
The equation of state of nuclear matter is studied in the 1-loop approximation of chiral linear σ-ω model.By introducing the density-dependent coupling constants, the problem of tachyon pole in the chiral σ-ω mode... The equation of state of nuclear matter is studied in the 1-loop approximation of chiral linear σ-ω model.By introducing the density-dependent coupling constants, the problem of tachyon pole in the chiral σ-ω model is resolved.The 1-loop contributions ofσ and π mesons to the nucleon's binding energy are included, while the empirical properties of nuclear matter such as saturation density, binding energy, and incompressibility are well reproduced. 展开更多
关键词 equation of state chiral σ-ω model
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Materials Design on the Origin of Gap States in a High-κ/GaAs Interface
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作者 Weichao Wang Cheng Gong +3 位作者 Ka Xiong Santosh K.C. Robert M.Wallace Kyeongjae Cho 《Engineering》 SCIE EI 2015年第3期372-377,共6页
Given the demand for constantly scaling micro- electronic devices to ever smaller dimensions, a SiO2 gate dielectric was substituted with a higher dielectric-constant material, Hf(Zr)O2, in order to minimize current... Given the demand for constantly scaling micro- electronic devices to ever smaller dimensions, a SiO2 gate dielectric was substituted with a higher dielectric-constant material, Hf(Zr)O2, in order to minimize current leakage through dielectric thin film. However, upon interfacing with high dielectric constant (high-κ) dielectrics, the electron mobility in the conventional Si channel degrades due to Coulomb scattering, surface-roughness scattering, remotephonon scattering, and dielectric-charge trapping.Ⅲ-Ⅴ and Ge are two promising candidates with superior mobility over Si. Nevertheless, Hf(Zr)O2/Ⅲ-Ⅴ(Ge) has much more complicated interface bonding than Si-based interfaces. Successful fabrication of a high-quality device critically depends on understanding and engineering the bonding configurations at Hf(Zr)O2/Ⅲ-Ⅴ(Ge) interfaces for the optimal design of device interfaces. Thus, an accurate atomic insight into the interface bonding and mechanism of interface gap states formation becomes essential. Here, we utilize first- principle calculations to investigate the interface between HfO2 and GaAs. Our study shows that As--As dimer bonding, Ga partial oxidation (between 3+ and 1+) and Ga- dangling bonds constitute the major contributions to gap states. These findings provide insightful guidance for optimum interface passivation. 展开更多
关键词 high-mobility device high-κ/Ⅲ- interface interfacial gap states first-principle calculations
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Public Building Supervisors' Assessment of Site Progress Record Keeping Practices in Abuja, Nigeria
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作者 Ikemefuna Mbamali Eyitene Aina Nesiama Ibrahim Khalilullahi Zubairu 《Journal of Civil Engineering and Architecture》 2012年第3期379-384,共6页
The importance of good site progress records in quality assurance; tracking project progress; preparing, analyzing and resolving claims; and placing responsibilities in the event of dispute in building contracts is wi... The importance of good site progress records in quality assurance; tracking project progress; preparing, analyzing and resolving claims; and placing responsibilities in the event of dispute in building contracts is widely recognized. This study engaged Public Building Supervisors in the assessment of site progress record keeping practices in Abuja. A simple structured questionnaire (which mainly assessed the nature and importance of records kept, reasons for keeping them; level of satisfaction with the current approach, challenges and practical ways of improving the practice) was administrated to a hundred of the supervisors, out of which seventy one was properly completed and returned. The results show that all five site progress documents (minutes of progress meetings, day-work sheets, photographs, weekly site records and personal site diaries) found in literature, are in use in Abuja, and have at least a high importance rating (i.e., relative importance index, 0.6 〈 RII 〈 0.8). Prominent among the reasons for keeping the records are: control of ongoing work (R11 = 0.83) data for estimating future works and terms of contract requirement (each with RII = 0.823). Though the present record keeping practices were largely assessed satisfactory, 95% of the Supervisors still yearned for improvement. The challenges to the current practice are consistent with those identified in literature and are: continuity consistency, legibility and accountability; in descending order of frequency of occurrence. Computerization, regular inspection of progress documents by assigned supervisors and in-house training of site staff are recommended for improving the record keeping practices. 展开更多
关键词 Site progress record - keeping site record practices in Abuja public building supervisors.
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