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Emerging perovskite materials for supercapacitors:Structure,synthesis,modification,advanced characterization,theoretical calculation and electrochemical performance
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作者 Yuehua Qian Qingqing Ruan +1 位作者 Mengda Xue Lingyun Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期41-70,I0003,共31页
As a new generation electrode materials for energy storage,perovskites have attracted wide attention because of their unique crystal structure,reversible active sites,rich oxygen vacancies,and good stability.In this r... As a new generation electrode materials for energy storage,perovskites have attracted wide attention because of their unique crystal structure,reversible active sites,rich oxygen vacancies,and good stability.In this review,the design and engineering progress of perovskite materials for supercapacitors(SCs)in recent years is summarized.Specifically,the review will focus on four types of perovskites,perovskite oxides,halide perovskites,fluoride perovskites,and multi-perovskites,within the context of their intrinsic structure and corresponding electrochemical performance.A series of experimental variables,such as synthesis,crystal structure,and electrochemical reaction mechanism,will be carefully analyzed by combining various advanced characterization techniques and theoretical calculations.The applications of these materials as electrodes are then featured for various SCs.Finally,we look forward to the prospects and challenges of perovskite-type SCs electrodes,as well as the future research direction. 展开更多
关键词 PEROVSKITE Modification engineering Oxygen vacancy theoretical calculation methodology SUPERCAPACITOR
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Theoretical Modeling and Surface Roughness Prediction of Microtextured Surfaces in Ultrasonic Vibration-Assisted Milling
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作者 Chenbing Ni Junjie Zhu +3 位作者 Youqiang Wang Dejian Liu Xuezhao Wang Lida Zhu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期163-183,共21页
Textured surfaces with certain micro/nano structures have been proven to possess some advanced functions,such as reducing friction,improving wear and increasing wettability.Accurate prediction of micro/nano surface te... Textured surfaces with certain micro/nano structures have been proven to possess some advanced functions,such as reducing friction,improving wear and increasing wettability.Accurate prediction of micro/nano surface textures is of great significance for the design,fabrication and application of functional textured surfaces.In this paper,based on the kinematic analysis of cutter teeth,the discretization of ultrasonic machining process,transformation method of coordinate systems and the cubic spline data interpolation,an integrated theoretical model was established to characterize the distribution and geometric features of micro textures on the surfaces machined by different types of ultrasonic vibration-assisted milling(UVAM).Based on the theoretical model,the effect of key process parameters(vibration directions,vibration dimensions,cutting parameters and vibration parameters)on tool trajectories and microtextured surface morphology in UVAM is investigated.Besides,the effect of phase difference on the elliptical shape in 2D/3D ultrasonic elliptical vibration-assisted milling(UEVAM)was analyzed.Compared to conventional numerical models,the method of the cubic spline data interpolation is applied to the simulation of microtextured surface morphology in UVAM,which is more suitable for characterizing the morphological features of microtextured surfaces than traditional methods due to the presence of numerous micro textures.The prediction of surface roughness indicates that the magnitude of ultrasonic amplitude in z-direction should be strictly limited in 1D rotary UVAM,2D and 3D UEVAM due to the unfavorable effect of axial ultrasonic vibration on the surface quality.This study can provide theoretical guidance for the design and fabrication of microtextured surfaces in UVAM. 展开更多
关键词 theoretical modeling Microtextured surface Ultrasonic vibration-assisted milling Cubic spline interpolation Surface roughness
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Evaluation of Medical Prescribers’ Theoretical Knowledge on Medical Imaging in the Northern Region of Burkina Faso
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作者 Some Milckisédek Judicaël Marouruana Ouedraogo Pakisba Ali +5 位作者 Tankoano Aïda Ida Savadogo Habibou Kindo Bassirou Ouedraogo Nina-Astrid Bamouni Yomboé Abel Diallo Ousseini 《Open Journal of Radiology》 2024年第2期33-41,共9页
Introduction: Medical imaging is a medical specialty that involves producing images of the human body and interpreting them for diagnostic, therapeutic purposes, and for monitoring the progress of pathologies. We aime... Introduction: Medical imaging is a medical specialty that involves producing images of the human body and interpreting them for diagnostic, therapeutic purposes, and for monitoring the progress of pathologies. We aimed to assess the theoretical knowledge of doctors and interns in medical imaging in the northern region of Burkina Faso. Methodology: This was a descriptive cross-sectional survey based on a self-administered questionnaire. Prescribers knowledge was estimated based on scores derived from questionnaire responses. Results: We collected 106 questionnaires out of 163, i.e. a participation rate of 65.03%. The average knowledge score was 81.71% for the contribution of medical imaging to patient management. It was 60.02% for the indications/counter-indications of radiological examinations and 72.56% for the risks associated with exposure to radiation during these examinations. The score was 59.83% for the methods used to select the appropriate radiological examination. As regards the completeness of the clinical and biological information on the forms requesting imaging examinations, the score was 96.65%. Specialist doctors had the highest overall level of knowledge (74.68%). Conclusion: Improved technical facilities, good initial and in-service training, and interdisciplinary collaboration will help to ensure that imaging tests are properly prescribed, leading to better patient care. 展开更多
关键词 theoretical Knowledge Medical Imaging Northern Region Burkina Faso
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Systematic and Theoretical Unfolding of Research on Xi Jinping’s Discourses on Respecting and Protecting Human Rights
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作者 张新平 周艺晨 LI Rong(Translated) 《The Journal of Human Rights》 2024年第2期255-286,共32页
Xi Jinping’s discourses on respecting and protect-ing human rights stand as a shining example of the sinicization and modernization of Marxist human rights theory,embodying profound theoretical,political,practical,an... Xi Jinping’s discourses on respecting and protect-ing human rights stand as a shining example of the sinicization and modernization of Marxist human rights theory,embodying profound theoretical,political,practical,and cultural logic.Existing research has conducted comprehensive and systematic theoretical analysis and academic extractions on the following contents:the core essence in-herent in these important discourses,including the“theory of human rights concepts,”the“theory of human rights paths,”the“theory of human rights practices,”the“theory of human rights protection,”and the“theory of human rights governance,”along with their profound theoretical significance,practical significance,and global signifi-cance.In the future,researchers should emphasize efforts on studying the original texts and understanding the original principles.While focusing on the precision of concepts,the scientific nature of the prop-ositions,the maturity of theoretical systems,and the rigor of internal logic related to Xi Jinping’s discourses on respecting and protecting human rights,researchers should also pay attention to constructing a discourse system on human rights from the dimensions of discourse power,discourse cluster,and discourse field.Researchers should be adept at drawing innovative insights into human rights theory from China’s vibrant human rights practices and the vast masses of people.This approach will facilitate the systematic unfolding,academic trans-formation,and innovative development of Xi Jinping’s discourses on respecting and protecting human rights. 展开更多
关键词 respecting and protecting human rights systematic nature of content theoretical transformation of achievements
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Evaluation of the Effectiveness of the “1 + 1 + 1” Method in Theoretical Teaching of Emergency Pericardiocentesis
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作者 Yudi Liu Wei Hu +7 位作者 Pei Wang Yue Yu Jin Rao Xiangyu Chen Pengchao Cheng Junnan Wang Yufeng Zhang Zhinong Wang 《Open Journal of Emergency Medicine》 2024年第2期59-67,共9页
Background: Pericardial effusion may progress to cardiac tamponade when pressure around the heart increases to a level comparable to that of the right and left atria. Patients with cardiac tamponade need timely comple... Background: Pericardial effusion may progress to cardiac tamponade when pressure around the heart increases to a level comparable to that of the right and left atria. Patients with cardiac tamponade need timely completion of emergency pericardiocentesis to relieve the threat to the patient’s life, and to save valuable time for patients who need emergency thoracotomy and pericardial window drainage. Pericardiocentesis is a necessary clinical skill for residents in standardized training. In addition, nurses who are familiar with this technology can better assist clinicians to perform this operation. In order to make the medical staff quickly master the theoretical knowledge of emergency pericardiocentesis, we designed a “1 + 1 + 1” teaching method for the theoretical teaching of emergency pericardiocentesis. Objective: This study aims to explore the effectiveness of the “1 + 1 + 1” teaching method in the theoretical teaching of emergency pericardiocentesis. Methods: We used an English teaching video of emergency pericardiocentesis and applied the “1 + 1 + 1” teaching method for theoretical teaching. A questionnaire survey was conducted before and after the lecture among 19 medical staff of different years of service to understand their mastery of the theoretical content of emergency pericardiocentesis before and after the lecture. According to the years of service, the medical staff were divided into three groups: 1 - 3 years (Group A), 4 - 10 years (Group B), and over 10 years (Group C), and the changes in the mastery of various contents by the overall medical staff and each group were statistically analyzed. Results: Before the lecture, the number of people who mastered the indications, contraindications, most commonly used methods, and common complications of emergency pericardiocentesis were 15, 12, 16, and 17, respectively, whereas after the lecture, these numbers increased to 17, 19, 19, and 19, respectively. The overall mastery before and after the lecture was statistically significant (p Conclusion: The “1 + 1 + 1” teaching method can effectively improve the overall mastery level of medical staff’s theoretical knowledge of emergency pericardiocentesis, especially in improving the mastery of contraindications of this operation. 展开更多
关键词 Cardiac Tamponade Emergency Pericardiocentesis theoretical Teaching
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Research on the Upper Limit of Accuracy for Predicting Theoretical Tandem Mass Spectrometry
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作者 Changjiu He Xiaoyu Wang +1 位作者 Mingming Lyu Xinye Bian 《Journal of Computer and Communications》 2024年第3期184-195,共12页
In recent years, numerous theoretical tandem mass spectrometry prediction methods have been proposed, yet a systematic study and evaluation of their theoretical accuracy limits have not been conducted. If the accuracy... In recent years, numerous theoretical tandem mass spectrometry prediction methods have been proposed, yet a systematic study and evaluation of their theoretical accuracy limits have not been conducted. If the accuracy of current methods approaches this limit, further exploration of new prediction techniques may become redundant. Conversely, a need for more precise prediction methods or models may be indicated. In this study, we have experimentally analyzed the limits of accuracy at different numbers of ions and parameters using repeated spectral pairs and integrating various similarity metrics. Results show significant achievements in accuracy for backbone ion methods with room for improvement. In contrast, full-spectrum prediction methods exhibit greater potential relative to the theoretical accuracy limit. Additionally, findings highlight the significant impact of normalized collision energy and instrument type on prediction accuracy, underscoring the importance of considering these factors in future theoretical tandem mass spectrometry predictions. 展开更多
关键词 Tandem Mass Spectrometry Spectral Prediction theoretical Limit
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Recent Progress in Atmospheric Chemistry Research in China: Establishing a Theoretical Framework for the “Air Pollution Complex” 被引量:2
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作者 Tong ZHU Mingjin TANG +40 位作者 Meng GAO Xinhui BI Junji CAO Huizheng CHE Jianmin CHEN Aijun DING Pingqing FU Jian GAO Yang GAO Maofa GE Xinlei GE Zhiwei HAN Hong HE Ru-Jin HUANG Xin HUANG Hong LIAO Cheng LIU Huan LIU Jianguo LIU Shaw Chen LIU Keding LU Qingxin MA Wei NIE Min SHAO Yu SONG Yele SUN Xiao TANG Tao WANG Tijian WANG Weigang WANG Xuemei WANG Zifa WANG Yan YIN Qiang ZHANG Weijun ZHANG Yanlin ZHANG Yunhong ZHANG Yu ZHAO Mei ZHENG Bin ZHU Jiang ZHU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第8期1339-1361,共23页
Atmospheric chemistry research has been growing rapidly in China in the last 25 years since the concept of the“air pollution complex”was first proposed by Professor Xiaoyan TANG in 1997.For papers published in 2021 ... Atmospheric chemistry research has been growing rapidly in China in the last 25 years since the concept of the“air pollution complex”was first proposed by Professor Xiaoyan TANG in 1997.For papers published in 2021 on air pollution(only papers included in the Web of Science Core Collection database were considered),more than 24000 papers were authored or co-authored by scientists working in China.In this paper,we review a limited number of representative and significant studies on atmospheric chemistry in China in the last few years,including studies on(1)sources and emission inventories,(2)atmospheric chemical processes,(3)interactions of air pollution with meteorology,weather and climate,(4)interactions between the biosphere and atmosphere,and(5)data assimilation.The intention was not to provide a complete review of all progress made in the last few years,but rather to serve as a starting point for learning more about atmospheric chemistry research in China.The advances reviewed in this paper have enabled a theoretical framework for the air pollution complex to be established,provided robust scientific support to highly successful air pollution control policies in China,and created great opportunities in education,training,and career development for many graduate students and young scientists.This paper further highlights that developing and low-income countries that are heavily affected by air pollution can benefit from these research advances,whilst at the same time acknowledging that many challenges and opportunities still remain in atmospheric chemistry research in China,to hopefully be addressed over the next few decades. 展开更多
关键词 atmospheric chemistry air pollution complex theoretical framework recent progress
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Enhancing effect of choline chloride-based deep eutectic solvents with polyols on the aqueous solubility of curcumin–insight from experiment and theoretical calculation
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作者 Wen Yu Yiyang Bo +3 位作者 Yiling Luo Xiyan Huang Rixiang Zhang Jiaheng Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第7期160-168,共9页
The development of green solvents for enhancing aqueous solubility of drug curcumin remains a challenge. This study explores the enhancing effect of deep eutectic solvents(DESs) on the aqueous solubility of curcumin(C... The development of green solvents for enhancing aqueous solubility of drug curcumin remains a challenge. This study explores the enhancing effect of deep eutectic solvents(DESs) on the aqueous solubility of curcumin(CUR) via experiment and theoretical calculation. Choline chloride-based DESs with polyols 1,2-propanediol(1,2-PDO), 1,3-propanediol, ethylene glycol, and glycerol as hydrogen bond donors were prepared and used as co-solvents. The CUR aqueous solubility increased with increasing the DESs content at temperature of 303.15-318.15 K, especially in aqueous ChCl/1,2-PDO(mole ratio 1:4) solutions. The positive apparent molar volume values and reduced density gradient analysis confirmed the existence of strong interactions between CUR and solvent. The van der Waals interactions and hydrogen bonding coexisted in DESs monomer retained the stability of DESs structure after introducing CUR. Moreover,the lower interaction energy of DESs…CUR system than that of the counterpart DESs further proved the strong interaction between CUR and DESs. The lowest interaction energy of ChCl/1,2-PDO…CUR system indicated that this system was the most stable and ChCl/1,2-PDO was promising for CUR dissolution.This work provides efficient solvents for utilizing curcumin, contributing to a deep insight into the interactions between DES and CUR at the molecular level, and the role of DESs on enhancing drugs solubility. 展开更多
关键词 Choline chloride-polyol Deep eutectic solvents CURCUMIN Aqueous solubility theoretical calculation
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Theoretical analyses on the one-dimensional charged particle transport in a decaying plasma under an electrostatic field
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作者 汪耀庭 孙鑫礼 +4 位作者 罗岚月 张子明 李和平 姜东君 周明胜 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期329-341,共13页
The spatiotemporal evolutions of a one-dimensional collisionless decaying plasma bounded by two electrodes with an externally applied electrostatic field are studied by theoretical analyses and particle-in-cell(PIC)si... The spatiotemporal evolutions of a one-dimensional collisionless decaying plasma bounded by two electrodes with an externally applied electrostatic field are studied by theoretical analyses and particle-in-cell(PIC)simulations with the ion extraction process in a laser-induced plasma as the major research background.Based on the theoretical analyses,the transport process of the charged particles including electrons and ions can be divided into three stages:electron oscillation and ion matrix sheath extraction stage,sheath expansion and ion rarefaction wave propagation stage and the plasma collapse stage,and the corresponding criterion for each stage is also presented.Consequently,a complete analytical model is established for describing the ion extraction flux at each stage during the decaying of the laser-induced plasmas under an electrostatic field,which is also validated by the PIC modeling results.Based on this analytical model,influences of the key physical parameters,including the initial electron temperature and number density,plasma width and the externally applied electric voltage,on the ratio of the extracted ions are predicted.The calculated results show that a higher applied electric potential,smaller initial plasma number density and plasma width lead to a higher ratio of the extracted ions during the first stage;while in this stage,the initial electron temperature shows little effect on it.Meanwhile,more ions will be extracted before the plasma collapse once a higher electric potential is applied.The theoretical model presented in this paper is helpful not only for a deep understanding to the charged particle transport mechanisms for a bounded decaying plasma under an applied electrostatic field,but also for an optimization of the ion extraction process in practical applications. 展开更多
关键词 transport of charged particles decaying plasma low-pressure plasma theoretical analysis particle-in-cell simulation
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Theoretical Transplantation into Translation Studies——An Analysis on the Pragmatic Application of Hofstede’s
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作者 ZHANG Zhi-chao WANG Guo-nian 《Journal of Literature and Art Studies》 2023年第7期514-521,共8页
The deepening process of globalization has given rise to restless cultural exchanges among people from different regions of the world through newspapers,books,and other written media.However,the significant difference... The deepening process of globalization has given rise to restless cultural exchanges among people from different regions of the world through newspapers,books,and other written media.However,the significant differences in languages and cultures have become an insurmountable gap in intercultural communication.To lubricate cultural exchanges,new translation theories that focus on the transformation of different cultural concepts shall be introduced and adopted.This paper aims to extract applicable notions from Hofstede’s Cultural Dimensions for pragmatic translation studies by laying emphasis on its pragmatic value through case study.By such theoretical transplantation,valuable suggestions are proposed to tackle cultural misunderstandings and conflicts encountered amid cultural exchanges. 展开更多
关键词 cultural exchange Hofstede’s Cultural Dimensions pragmatic translation studies theoretical transplantation
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Theoretical prediction of forming limit diagram of AZ31 magnesium alloy sheet at warm temperatures 被引量:3
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作者 曹晓卿 徐平平 +1 位作者 樊奇 王文先 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第9期2426-2432,共7页
A theoretical prediction on forming limit diagram(FLD) of AZ31 magnesium alloy sheet was developed at warm temperatures based on the M-K theory. Two different yield criteria of von Mises and Hill'48 were applied in... A theoretical prediction on forming limit diagram(FLD) of AZ31 magnesium alloy sheet was developed at warm temperatures based on the M-K theory. Two different yield criteria of von Mises and Hill'48 were applied in this model. Mechanical properties of AZ31 magnesium alloy used in the prediction were obtained by uniaxial tensile tests and the Fields-Backofen equation was incorporated in the analysis. In addition, experimental FLDs of AZ31 were acquired by conducting rigid die swell test at different temperatures to verify the prediction. It is demonstrated from a comparison between the predicted and the experimental FLDs at 473 K and 523 K that the predicted results are influenced by the type of yield criterion used in the calculation, especially at lower temperatures. Furthermore, a better agreement between the predicted results and experimental data for AZ31 magnesium alloy sheet at warm temperatures was obtained when Hill'48 yield criterion was applied. 展开更多
关键词 magnesium alloy forming limit diagram theoretical prediction yield criterion sheet warm forming
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Theoretical analysis on springback of L-section extrusion in rotary stretch bending process 被引量:13
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作者 于成龙 李小强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2705-2710,共6页
The theoretical analysis of springback in rotary stretch bending process of L-section extrusion was studied. The models for characterizing the springback angle after unloading were established based on the stress and ... The theoretical analysis of springback in rotary stretch bending process of L-section extrusion was studied. The models for characterizing the springback angle after unloading were established based on the stress and strain distributions in the cross-section of the part. With the proposed model, analysis of the effect of pre-stretch force and post-stretch force on springback angle shows that springback decreases as the pre-stretch force or post-stretch force increases. Comparative study with experiments clearly demonstrates that the prediction of springback can resort to the current model without the loss of accuracy. 展开更多
关键词 SPRINGBACK rotary stretch bending theoretical analysis
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Theoretical Framework for Circular Agricultural Science and Technology Park Planning 被引量:4
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作者 薛辉 赵肖玲 +1 位作者 张高棣 冯永忠 《Agricultural Science & Technology》 CAS 2012年第3期689-692,共4页
In the paper, theoretical framework of Circular Agricultural Science and Technology Park planning was constructed based on circular agriculture, modern agriculture, garden landscape and management of agriculture SciTe... In the paper, theoretical framework of Circular Agricultural Science and Technology Park planning was constructed based on circular agriculture, modern agriculture, garden landscape and management of agriculture SciTech park, and the concerning meaning and characteristics were introduced, providing theoretical bases and guidance for circular agriculture SciTech park. 展开更多
关键词 Circular agriculture Science and Technology Park PLANNING theoretical framework
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Theoretical investigations on CO oxidation reaction catalyzed by gold nanoparticles 被引量:2
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作者 孙科举 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第10期1608-1618,共11页
It is crucial to understand the mechanism of low temperature CO oxidation reaction catalyzed by gold nanoparticles so as to find out the origin of the high catalytic reactivity and extend the indus‐trialization appli... It is crucial to understand the mechanism of low temperature CO oxidation reaction catalyzed by gold nanoparticles so as to find out the origin of the high catalytic reactivity and extend the indus‐trialization applications of nano gold catalysts. In this work, some theoretical works on CO adsorp‐tion, O2 adsorption, atomic oxygen adsorption, formation of surface gold oxide films, reaction mechanisms of CO oxidation involving O2 reaction with CO and O2 dissociation before reacting with CO on gold surfaces and Au/metal oxide were summarized, and the influences of coordination number, charge transfer and relativity of gold on CO oxidation reaction were briefly reviewed. It was found that CO reaction mechanism depended on the systems with or without oxide and the strong relativistic effects might play an important role in CO oxidation reaction on gold catalysts. In particular, the relativistic effects are related to the unique behaviors of CO adsorption, O adsorption, O2 activation on gold surfaces, effects of coordination number and the wide gap between the chem‐ical inertness of bulk gold and high catalytic activity of nano gold. The present work helps us to understand the CO oxidation reaction mechanism on gold catalysts and the influence of relativistic effects on gold catalysis. 展开更多
关键词 Carbon monoxide oxidation reaction Gold nanoparticle Reaction mechanism theoretical calculation Relativistic effect
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Theoretical Study on Dissociation Potential Energy Surface of Peroxynitric Acid
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作者 韦文美 郑仁慧 +2 位作者 吴允凯 杨帆 洪石 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第6期659-662,I0003,共5页
The lowest energy structures of peroxynitric acid have been studied with B3LYP/6-311+ G(2d,2p) method. The potential energy surfaces (PES) along the O-N and O-O bonds have been scanned at CCSD(T)/aug-cc-pVDZ le... The lowest energy structures of peroxynitric acid have been studied with B3LYP/6-311+ G(2d,2p) method. The potential energy surfaces (PES) along the O-N and O-O bonds have been scanned at CCSD(T)/aug-cc-pVDZ level, respectively. The calculated results show that on the O-N PES, the O3-N4 bond length of the loose transition state is 2.82A^° and the corresponding energy barrier is 25.6 kcal/mol, while on the O-O PES, the loose transition state with of O2-O3 bond length of 2.35A^° has the energy barrier of 37.4 kcal/mol. Thus the primary reaction path for peroxynitric acid is the dissociation into HO2 and NO2. 展开更多
关键词 Peroxynitric acid STRUCTURE Potential energy surface theoretical study
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Theoretical Study on Raman Spectra of Aqueous Peroxynitric Acid
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作者 韦文美 郑仁慧 +4 位作者 景园园 刘雅婷 胡骏程 叶勇 史强 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第5期625-630,I0004,共7页
Using density functional theory and polarizable continuum models, we study the Raman spectra of aqueous peroxynitric acid. The calculated results indicate that the solvent effect has significant influence on the elect... Using density functional theory and polarizable continuum models, we study the Raman spectra of aqueous peroxynitric acid. The calculated results indicate that the solvent effect has significant influence on the electric dipole transition moments between the ground and excited electronic state and Raman polarizabilities. The theoretical Raman spectra agree well with the experimental results. From the experimental depolarization ratio, we can conclude that peroxynitric acid is not a plane molecule. We also find that the hydrogen bond can enhance IR intensity of hydroxyl group by several times. 展开更多
关键词 Aqueous peroxynitric acid RAMAN theoretical study
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The theoretical expressions of wood thermal diffusivity
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作者 杨庆贤 杨绮 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第2期133-135,共3页
From viewpoint of chemical element and microstructure of wood, this paper makes a discussion on thermal diffusivity of wood and two theoretical expressions of thermal diffusivity for the choral and radial directions w... From viewpoint of chemical element and microstructure of wood, this paper makes a discussion on thermal diffusivity of wood and two theoretical expressions of thermal diffusivity for the choral and radial directions were derived. The thermal diffusivities of the choral and radial directions for about 20 species of trees were calculated with the derived theoretical expressions and compared with the experimental values. The average error of the theoretical values of thermal diffusivity was 7.5% for choral direction and 6.2% for radial direction. 展开更多
关键词 Thermal diffusivity theoretical expression WOOD
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Hydrodynamics of Liquid Flow in the Model of Theoretical Stage with Perfect Displacement
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作者 Volodymyr Maletal Vitaliy Taran Bogdan Maleta 《Journal of Chemistry and Chemical Engineering》 2011年第1期25-29,共5页
For the cyclic process of mass transfer in tray columns there are considered the hydrodynamic models of liquid flow during steam supply and during overflow of liquid from tray to tray. During steam supply, the hydrody... For the cyclic process of mass transfer in tray columns there are considered the hydrodynamic models of liquid flow during steam supply and during overflow of liquid from tray to tray. During steam supply, the hydrodynamic model is determined as perfect displacement model, and during liquid overflow, it is described as cell model. There were received the characteristics of liquid flow as follows: average residence time of liquid, degree of dispersion around the mean on the tray, number of perfect mixing cells depending on multiplication factor of exchange of liquid delay. In Y-X coordinates there is depicted a work line and theoretical stage of perfect displacement model. There were considered the conditions of mutual transfer of theoretical stage and theoretical stage with perfect displacement. The advantages of the mass transfer cyclic process to the stationary one arc stated. 展开更多
关键词 mass transfer cyclic distillation theoretical stage the theoretical stage model with perfect displacement residence time
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SOME THEORETICAL EXPLORATIONS ON INTERCULTURALCOMMUNICATILN STUDIES
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作者 贾永芳 《内蒙古工业大学学报(社会科学版)》 2003年第2期87-93,共7页
This paper mainly focuses on the theoretical bases of intercultural communication by analyzing reasons of IC studies’emergence,researches done on IC by linguists and English teachers,and some difficulties concerning ... This paper mainly focuses on the theoretical bases of intercultural communication by analyzing reasons of IC studies’emergence,researches done on IC by linguists and English teachers,and some difficulties concerning intercultural communication studies. 展开更多
关键词 PRAGMATIC FAILURE INTERCULTURAL communication STUDIES theoretical BASES
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A Theoretical Analysis on Features of Linguistic Decategorization
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作者 周吉红 《海外英语》 2013年第13期265-266,268,共3页
Liu Zhengguang made a conclusion about features of linguistic decategorization on the semantic,morphonological,textual and categorial attributes levels.However,these features were too specific to reflect the holistic ... Liu Zhengguang made a conclusion about features of linguistic decategorization on the semantic,morphonological,textual and categorial attributes levels.However,these features were too specific to reflect the holistic characteristics of linguistic decategorization.Taking a holistic point of view,this paper will make a tentative study to summarize the features of linguistic decategorization.This paper maintains that 1) linguistic decategorization is a dynamic and gradual process;2) linguistic decategorization is uneven at multilevel;3) linguistic decategorization is context-dependent and unpredictable. 展开更多
关键词 theoretical ANALYSIS LINGUISTIC DECATEGORIZATION
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