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从语录流行语到词语流行语 被引量:26
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作者 李明洁 《修辞学习》 北大核心 2009年第3期70-78,共9页
语录流行语是以语录为载体的话语成品的流行现象,有整体复制和引用类比两种流行方式,具有入境性的特点。语录流行语中有一部分会经过语义投射和词语提取等词语化的手段转换为词语流行语,并按照词语流行语的一般规律,通过高频使用和词义... 语录流行语是以语录为载体的话语成品的流行现象,有整体复制和引用类比两种流行方式,具有入境性的特点。语录流行语中有一部分会经过语义投射和词语提取等词语化的手段转换为词语流行语,并按照词语流行语的一般规律,通过高频使用和词义泛化而得以流行。本文从社会动因、认知规律,尤其是语言特征的层面综合分析了流行语传播中的类型转换现象,阐明了语言流行的两种载体间的差异,论证了语录流行语转换至词语流行语的方式和意义。 展开更多
关键词 语录流行语 词语流行语 入境 离境性 语义投射 词语提取
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Durability related environmental zonation and design methodology for marine RC structures 被引量:1
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作者 Wu Hairong Lü Qingfang Jin Weiliang 《Journal of Southeast University(English Edition)》 EI CAS 2018年第1期78-86,共9页
A reliability-based quantitative durability design methodology is presented for reinforced concrete(RC)structures in the marine environment on the basis of natural exposure data derived from four berths(1.5,1.5,4 and ... A reliability-based quantitative durability design methodology is presented for reinforced concrete(RC)structures in the marine environment on the basis of natural exposure data derived from four berths(1.5,1.5,4 and 15 years)of a concrete port.More than 200 chloride profiles are obtained and analyzed.The relationship between nominal surface chloride ion concentration and altitude is discussed.Subsequently,the formula of the apparent chloride diffusion coefficient is proposed with consideration of the surrounding temperature,sodium chloride solution concentration,age factor and altitude.Then,the reliability-based method to predict the durability of RC structures is developed according to Fick s second law.Relationships between the predicted penetration depth of the chloride ion,the ratio of the wetting time per-period and the corresponding altitude are discussed.Subsequently,the environmental zonation methodology is established for concrete structures under a marine chloride environment by considering the ratio of the wetting time per-period of concrete as the zoning index.Finally,the corres-ponding durability design method for each zone level is established,which contains the durability design regulations of the specimen,and correction coefficients for different water/binder ratios,ages,temperatures and chloride ion concentrations. 展开更多
关键词 reinforced concrete structure MARINE chloride ion ENVIRONMENT ZONATION durability design
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Urea Preparation by Oxidative Carbonylation of Ammonia 被引量:2
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作者 A.R. Elman V.I. Smirnov 《Journal of Environmental Science and Engineering》 2011年第8期1006-1012,共7页
Effective one-stage method of urea preparation by catalytic oxidative carbonylation of ammonia in liquid phase is developed. The method allows to prepare urea with productivity of-530 g/(L·h) in sufficiently mi... Effective one-stage method of urea preparation by catalytic oxidative carbonylation of ammonia in liquid phase is developed. The method allows to prepare urea with productivity of-530 g/(L·h) in sufficiently mild conditions (total pressure -30 bar, 45 ℃). The process is characterized by high selectivity (near 100%) i.e. byproducts separation is not needed. Almost all CO is consumed during the process, this substantially diminishes the waste-gas purification costs and raises the process environmental characteristics; the only byproduct is water. 展开更多
关键词 UREA ammonia oxidative carbonylation SELENIUM heat efficiency
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Effect of Environment on Photo-detachment Dynamics of Halide Ions: A Model Approach
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作者 Bikram Nath Chandan Kumar Mondal 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期30-38,I0001,共10页
A two dimensional model approach for the photodetachment dynamics of closed shell an-ionic systems in presence of external light field have been proposed in the context of polar environmental media. The effects of str... A two dimensional model approach for the photodetachment dynamics of closed shell an-ionic systems in presence of external light field have been proposed in the context of polar environmental media. The effects of strong coupling between the solvent polarization and the extra charge in the system were studied by a simple model. The electronic states of con-cerned halide ions are represented by a two dimensional model Hamiltonian with a potential V(x,y)=-V0e^-σ(x^2+y^2). The time dependent Fourier grid Hamiltonian method have been used to follow the detachment process with fairly high intensities of light. The environmental effects on the dynamics are sought to be modeled by two different ways. The first one was the presence of polar solvents which perturb the energy levels of anionic systems by changing the effective potential surface and the second one was allowing the fluctuation of the well depth randomly to mimic the system in a more realistic view point. The average detachment rate constant is calculated as a function of important parameters of the used light field to explain the effects of solvent field on the dynamical behavior of dipole bound anionic system at least in a qualitative way. 展开更多
关键词 Photodetachment dynamics Environmental effect Time-dependent Fourier grid Hamiltonian Stochastic deactivation
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Modification of pore size in activated carbon by benzene deposition and its effects on CH4/N2 separation 被引量:2
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作者 ZHANG Jin-hua CHE Yong-fang +1 位作者 LI Lan-ting BAO Peng-cheng 《Journal of Coal Science & Engineering(China)》 2011年第4期418-421,共4页
Anthracite coal was used as raw material to prepare activated carbons as the carbon support in the carbonization-activation process. Modification of the pore size of the activated carbon by chemical vapor deposition o... Anthracite coal was used as raw material to prepare activated carbons as the carbon support in the carbonization-activation process. Modification of the pore size of the activated carbon by chemical vapor deposition of carbon from benzene was examined. These samples were characterized by adsorption of N2 at 77 K and CH4 and N2 at 303 K. The microporosity of these samples was evaluated by the Dubinin-Astakhov Equation. The pore size distribution was obtained by the DFT method applied to the N2 adsorption data at 77 K. The separation selectivity was obtained by the Langmuir Equation. The surface morphology was characterized by an environmental scanning electron microscope. It was observed that all samples of carbon molecular sieves studied were microporous carbonaceous materials. CMS-2 prepared in the present study has a better N2/CH4 separation performance; it can satisfy the requirements of the pressure swing adsorption for concentrating CH4 from the N2/CH4 mixture gas. 展开更多
关键词 benzene deposition carbon molecular sieves adsorption property
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Reliability-based service life prediction of existing concrete structures under marine environment 被引量:1
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作者 吴灵杰 周拥军 +1 位作者 寇新建 蒋萌 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第9期3608-3614,共7页
Chloride-induced corrosion of the reinforcement is considered as one of the major mechanisms resulting in the reduction of structural resistance of reinforced concrete structural elements located in marine and other a... Chloride-induced corrosion of the reinforcement is considered as one of the major mechanisms resulting in the reduction of structural resistance of reinforced concrete structural elements located in marine and other aggressive environments. A study of reinforced concrete structures located at the Fangcheng dock in the Beibu Gulf port, China, was present. The result from field survey indicates that the concrete cover depth and chloride diffusion coefficient fit best normal distribution and lognormal distribution, respectively. The service life of structure is about 55 a, while initiation time is 45 a. Sensitivity analysis indicates that the most influential factor of the structure service life prediction is concrete cover, followed by diffusion coefficient, diffusion decay index, critical chloride concentration, surface chloride concentration, current density and localized pitting corrosion. Finally, the effects of diffusion decay index and critical chloride concentration on structure service life prediction are discussed. 展开更多
关键词 CHLORIDE existing concrete structure service life marine environment
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Molecular characterization of Acidithiobacillus ferrooxidans strains isolated from different environments by three PCR-based methods
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作者 吴学玲 刘莉莉 +2 位作者 张真真 邓凡凡 刘新星 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期455-465,共11页
PCR-based DNA fingerprinting, REP-PCR(repetitive element PCR), RAPD(randomly amplified polymorphic DNA) and16 S r DNA sequence analyses were used to characterize 23 Acidithiobacillus ferrooxidans strains isolated from... PCR-based DNA fingerprinting, REP-PCR(repetitive element PCR), RAPD(randomly amplified polymorphic DNA) and16 S r DNA sequence analyses were used to characterize 23 Acidithiobacillus ferrooxidans strains isolated from different environments.(GTG)5 and BOXA1 R primer were selected for REP-PCR. Twenty arbitrary primers were used for RAPD to acquire DNA profiles from A. ferrooxidans. Both RAPD and REP-PCR produce complex banding patterns and show good discriminatory ability in differentiating closely related strains of A. ferrooxidans. The strains are clustered into 4 or 5 major groups and reveal genomic diversity using(GTG)5-PCR, BOX-PCR and RAPD analysis. Phylogenetic tree based on 16 S r DNA sequences of 23 strains and related strains shows that they are clustered into two distinct groups. Twelve strains are highly related to a new Acidithiobacillus named Acidithiobacillus ferrivorans. The results indicate that PCR-based methods are effective in revealing genetic diversity among A. ferrooxidans. 展开更多
关键词 Acidithiobacillus ferrooxidans repetitive element PCR(REP-PCR) randomly amplified polymorphic DNA(RAPD) 16S r DNA sequence analysis genetic diversity
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Promotion of Adhesive Polymer Bonding by Plasma Modification Using Defined Ambient Conditions and Process Gases
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作者 Vitali Fischer Elisabeth Stammen +3 位作者 Klaus Dilger Marko Eichler Sascha Paulmann Claus-Peter Klages 《Journal of Energy and Power Engineering》 2017年第2期135-139,共5页
Adhesive bonding technology is often the preferred solution for the joining of polymers. In many cases a wet chemical pretreatment has to he used to achieve sufficient adhesion strength and durability of the adhesive ... Adhesive bonding technology is often the preferred solution for the joining of polymers. In many cases a wet chemical pretreatment has to he used to achieve sufficient adhesion strength and durability of the adhesive joint. Since several years, plasma treatment has been a proven method to attain these goals. However, conventional treatments in oxidizing gases such as air are often not satisfying. In this work, the PP (polymers polypropylene), PVDF (polyvinylidene fluoride), PA6 (polyamide 6), POM (polyoxymethylene) and PC (polycarbonate) were pretreated by means of a plasma jet running at atmospheric pressure in a virtually oxygen-free atmosphere. The goal was the grafting of reactive nitrogen-containing functional groups on the plastic surfaces in order to increase the adhesive strength. 展开更多
关键词 Plasma modification FUNCTIONALIZATION functional groups atmospheric pressure plasma oxygen-free atmosphere.
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A novel low-cost and environment-friendly cathode with large channels and high structure stability for potassium-ion storage 被引量:3
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作者 Weike Wang Bifa Ji +6 位作者 Wenjiao Yao Xinyuan Zhang Yongping Zheng Xiaolong Zhou Pinit Kidkhunthod Haiyan He Yongbing Tang 《Science China Materials》 SCIE EI CAS CSCD 2021年第5期1047-1057,共11页
Potassium-ion batteries (KIBs) are promising candidates for large-scale energy storage due to the abundance of potassium and its chemical similarity to lithium.Nevertheless,the performances of KIBs are still unsatisfa... Potassium-ion batteries (KIBs) are promising candidates for large-scale energy storage due to the abundance of potassium and its chemical similarity to lithium.Nevertheless,the performances of KIBs are still unsatisfactory for practical applications,mainly hindered by the lack of suitable cathode materials.Herein,combining the strong inductive effect of sulphate and the feasible preparation of Fe^(2+)-containing compounds in oxalate system,a compound with novel architecture,K_(4)Fe_(3)(C_(2)O_(4))_(3)(SO_(4))_(2),has been identified as a lowcost and environmentally friendly cathode for stable potassium-ion storage.Its unique crystal structure possesses an unprecedented two-dimensional framework of triple layers,with 3.379Åinterlayer distance and large intralayer rings in the size of 4.576×6.846Å.According to first-principles simulations,such a configuration is favorable for reversible K-ion migration with a very low volume change of 6.4%.Synchrotron X-ray absorption spectra and X-ray diffraction characterizations at different charging/discharging states and electrochemical performances based on its half and full cells further verify its excellent reversibility and structural stability.Although its performance needs to be improved via further composition tuning with multi-valent transition metals,doping,structural optimization,etc.,this study clearly presents a stable structural model for K-ion cathodes with merits of low cost and environmental friendliness. 展开更多
关键词 potassium-ion cathode Fe-based polyanionic compound low cost environment friendly
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Ionic effects on the transport characteristics of nanowire-based FETs in a liquid environment
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作者 Daijiro Nozaki Jens Kunstmann +5 位作者 Felix Zorgiebel Sebastian Pregl Larysa Baraban Walter M. Weber Thomas Mikolajick Gianaurelio Cuniberti 《Nano Research》 SCIE EI CAS CSCD 2014年第3期380-389,共10页
For the development of ultra-sensitive electrical bio/chemical sensors based on nanowire field effect transistors (FETs), the influence of the ions in the solution on the electron transport has to be understood. For... For the development of ultra-sensitive electrical bio/chemical sensors based on nanowire field effect transistors (FETs), the influence of the ions in the solution on the electron transport has to be understood. For this purpose we establish a simulation platform for nanowire FETs in the liquid environment by implementing the modified Poisson-Boltzmann model into Landauer transport theory. We investigate the changes of the electric potential and the transport characteristics due to the ions. The reduction of sensitivity of the sensors due to the screening effect from the electrolyte could be successfully reproduced. We also fabricated silicon nanowire Schottky-barrier FETs and our model could capture the observed reduction of the current with increasing ionic concentration. This shows that our simulation platform can be used to interpret ongoing experiments, to design nanowire FETs, and it also gives insight into controversial issues such as whether ions in the buffer solution affect the transport characteristics or not. 展开更多
关键词 nanowire field effecttransistors (FETs) biosensors silicon nanowires Poisson-Boltzmann theory Landauer model
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