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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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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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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 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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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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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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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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Prediction of the amount of urban waste solids by applying a gray theoretical model 被引量:11
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作者 LI Xiao ming, ZENG Guang ming, WANG Ming, LIU Jin jin (Department of Environmental Science and Technology, Hunan University, Changsha 410082, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第1期43-46,共4页
Urban waste solids are now becoming one of the most crucial environmental problems. There are several different kinds of technologies normally used for waste solids disposal, among which landfill is more favorable in ... Urban waste solids are now becoming one of the most crucial environmental problems. There are several different kinds of technologies normally used for waste solids disposal, among which landfill is more favorable in China than others, especially for urban waste solids. Most of the design works up to now are based on a roughly estimation of the amount of urban waste solids without any theoretical support, which lead to a series problems. To meet the basic information requirements for the design work, the amount of the urban waste solids was predicted in this research by applying the gray theoretical model GM (1,1) through non linear differential equation simulation. The model parameters were estimated with the least square method (LSM) by running a certain MATALAB program, and the hypothesis test results show that the residual between the prediction value and the actual value approximately comply with the normal distribution N (0,0 21 2), and the probability of the residual within the range (-0 17, 0 19) is more than 95%, which indicate obviously that the model can be well used for the prediction of the amount of waste solids and those had been already testified by the latest two years data about the urban waste solids from Loudi City of China. With this model, the predicted amount of the waste solids produced in Loudi City in the next 30 years is 8049000 ton in total. 展开更多
关键词 gray theoretical model PREDICTION waste solids
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Experimental, Numerical and Simplified Theoretical Model Study for Internal Solitary Wave Load on FPSO with Emphasis on Scale Effect 被引量:6
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作者 ZHANG Rui-rui CHEN Ke YOU Yun-xiang 《China Ocean Engineering》 SCIE EI CSCD 2019年第1期26-33,共8页
Scale effect of ISWs loads on Floating Production Storage and Offloading(FPSO) is studied in this paper. The application conditions of KdV, eKdV and MCC ISWs theories are used in the numerical method. The depthaverage... Scale effect of ISWs loads on Floating Production Storage and Offloading(FPSO) is studied in this paper. The application conditions of KdV, eKdV and MCC ISWs theories are used in the numerical method. The depthaveraged velocities induced by ISWs are used for the velocity-inlet boundary. Three scale ratio numerical models λ=1, 20 and 300 were selected, which the scale ratio is the size ratio of numerical models to the experimental model.The comparisons between the numerical and former experimental results are performed to verify the feasibility of numerical method. The comparisons between the numerical and simplified theoretical results are performed to discuss the applicability of the simplified theoretical model summarized from the load experiments. Firstly, the numerical results of λ=1 numerical model showed a good agreement with former experimental and simplified theoretical results. It is feasible to simulate the ISWs loads on FPSO by the numerical method. Secondly, the comparisons between the results of three scale ratio numerical models and experimental results indicated that the scale ratios have more significant influence on the experimental horizontal forces than the vertical forces. The scale effect of horizontal forces mainly results from the different viscosity effects associated with the model’s dimension.Finally, through the comparisons between the numerical and simplified theoretical results for three scale ratio models, the simplified theoretical model of the pressure difference and friction forces exerted by ISWs on FPSO is applied for large-scale or full-scale FPSO. 展开更多
关键词 scale effect FPSO INTERNAL SOLITARY wave NUMERICAL simulation simplified theoretical model
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Theoretical Calculation Model of Heat Transfer for Deep-derived Supercritical Fluids with a Case Study 被引量:6
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作者 HUWenxuan JINZhijun +2 位作者 SONGYucai SUNRui DUANZhenhao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期221-229,共9页
Based on a set of equations established by Duan et al. (1992, 1996) for a geofluid system H2O-CO2-CH4(-N2), a formula is obtained to calculate the heat changes. Combining the geological T-P conditions (geothermal grad... Based on a set of equations established by Duan et al. (1992, 1996) for a geofluid system H2O-CO2-CH4(-N2), a formula is obtained to calculate the heat changes. Combining the geological T-P conditions (geothermal gradients and lithostatic and hydrostatic pressures), the enthalpy of some typical geofluids is figured out. Then the principles of heat transfer of deep-derived supercritical fluids are discussed. The result shows that deep-derived geofluids can bring a large amount of thermal heat and release most heat to the shallow surroundings as they move up, because the molar enthalpies vary very greatly from the deep to shallow, increasing with the increases of T and P. Generally, more than tens of kilojoules heat per molar can be released. Furthermore, the molar enthalpy is affected by the compositions of the geofluids, and the molar enthalpy of CO2, CH4, or N2 is greater than that of H2O, being twice, more than twice, and about 140% of H2O, respectively. Finally, a case study is conducted by investigating a source rock sequence affected hydrothermally by magmatic fluids in the Huimin depression of Shengli Oilfield. The thermal heat calculated theoretically of the fluids related to a diabase intrusion is quite large, which can increase the temperature near the diabase to about 300℃, and that can, to some extent, account for the abnormal rise of the vitrinite reflectance, with the highest of about 3.8% (Ro). 展开更多
关键词 heat transfer ENTHALPY theoretical calculation deep-derived fluids a case study
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Study of the theoretical tensile strength of Fe by a first-principles computational tensile test 被引量:4
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作者 刘悦林 张颖 +1 位作者 洪荣杰 吕广宏 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第5期1923-1930,共8页
This paper employs a first-principles total-energy method to investigate the theoretical tensile strengths of bcc and fcc Fe systemically. It indicates that the theoretical tensile strengths are shown to be 12.4, 32.7... This paper employs a first-principles total-energy method to investigate the theoretical tensile strengths of bcc and fcc Fe systemically. It indicates that the theoretical tensile strengths are shown to be 12.4, 32.7, 27.5 GPa for bcc Fe, and 48.1, 34.6, 51.2 GPa for fcc Fe in the [001], [110] and [111] directions, respectively. For bcc Fe, the [001] direction is shown to be the weakest direction due to the occurrence of a phase transition from ferromagnetic bcc Fe to high spin ferromagnetic fcc Fe. For fcc Fe, the [110] direction is the weakest direction due to the formation of an instable saddle-point 'bct structure' in the tensile process. Furthermore, it demonstrates that a magnetic instability will occur under a tensile strain of 14%, characterized by the transition of ferromagnetic bcc Fe to paramagnetic fcc Fe. The results provide a good reference to understand the intrinsic mechanical properties of Fe as a potential structural material in the nuclear fusion Tokamak. 展开更多
关键词 FE theoretical tensile strength phase transition first-principles computational tensiletest
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Theoretical Study on Sulfur Dioxide Absorption with Citrate Solution 被引量:3
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作者 薛娟琴 洪涛 +1 位作者 王召启 李林波 《过程工程学报》 EI CAS CSCD 北大核心 2006年第3期388-391,共4页
关键词 citrate solution ABSORPTION sulfur dioxide theoretical analysis
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Brief report on theoretical research upon wood thermal property 被引量:2
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作者 杨庆贤 张春英 《Journal of Forestry Research》 CAS CSCD 2000年第2期145-146,共2页
In this paper, the theoretical expressions of the specific heat and thermal conductivity of wood are first derived from the micro-Structure of wood by applying some basic principles in statistical thermodynamics and p... In this paper, the theoretical expressions of the specific heat and thermal conductivity of wood are first derived from the micro-Structure of wood by applying some basic principles in statistical thermodynamics and physical mechanics. Tested by a great rnany experiments, the average error of theoretical values is about 5%,much less than that of all kinds of exiting empiric equations in the world. 展开更多
关键词 SPECIFIC heat thermal CONDUCTIVITY theoretical expression WOOD
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A New One-dimensional Coordination Polymer Based on 3,5-Dinitro-salicylic Acid:Synthesis,Crystal Structure,Luminescent Property and Theoretical Calculation 被引量:4
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作者 孔治国 刘东雪 +3 位作者 李芮 江月 王丽娟 胡波 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第5期841-847,共7页
A new one-dimensional Mg(Ⅱ) coordination polymer, [Mg(L)(phen)(H2O)](1), has been hydrothermally synthesized by using 3,5-dinitro-salicylic acid(H2L) and 1,10-phenanthroline(phen). It crystallizes in mo... A new one-dimensional Mg(Ⅱ) coordination polymer, [Mg(L)(phen)(H2O)](1), has been hydrothermally synthesized by using 3,5-dinitro-salicylic acid(H2L) and 1,10-phenanthroline(phen). It crystallizes in monoclinic, space group C2/c with a = 33.038(7), b = 6.6481(13), c = 22.750(5) A, β = 126.99(3)°, V = 3991.1(14) A3, Z = 8, C19H12 MgN4O8, Mr = 448.64, Dc = 1.493 g/cm3, F(000) = 1840, μ(Mo Ka) = 0.146 mm-1, R = 0.0559 and w R = 0.0975. In 1, each L anion bridges two Mg(Ⅱ) atoms to give one-dimensional zigzag chains with the Mg…Mg separation of 5.34 ?, which are extended by π-π stacking interactions between 1,10-phenanthroline ligands into a two-dimensional supramolecular layer. Moreover, the O–H…O hydrogen-bonding interactions further stabilize the layer structure of 1. The luminescent property was also studied for 1 in solid state at room temperature. In addition, natural bond orbital(NBO) analysis was performed by the B3LYP/LANL2 DZ method in Gaussian 09 Program. The calculation results show obvious covalent interaction between the coordinated atoms and Mg(Ⅱ) ion. 展开更多
关键词 luminescent property crystal structure coordination polymer theoretical calculation
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Theoretical Model of Transformation Superlastic Diffusion Bonding for Eutectoid Steel 被引量:2
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作者 LU Shi-hong, YUN Jun-bi (College of Mechanic and Electricial Engineering, Nanjing University of Aeronautics & Astronautics, Nanjing 210016, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期13-14,共2页
Based on current theories of diffusion and creep cavity closure at high temperature, a theoretical analysis of phase transformation diffusion bonding for T8/T8 eutectoid steel is carried out. The diffusion bonding is ... Based on current theories of diffusion and creep cavity closure at high temperature, a theoretical analysis of phase transformation diffusion bonding for T8/T8 eutectoid steel is carried out. The diffusion bonding is mainly described as two-stage process: Ⅰ The interfacial cavity with shape change from diamond to cylinder.Ⅱ The radius of the cylindrical cavity are reduced and eliminated gradually. A new theoretical model is established for the process of transformation superplastic diffusion bonding (TSDB) on the basis of a theoretical model for isothermal superplastic diffusion. The model can predict the bonding quality which is affected by technological parameters, such as limit cycling temperature, the compressive stress, the numbers of thermal cycles and temperature cycling through the phase transformation in the thermal cycling and so on. Results show that the maximum temperature, the compressive stress, the numbers of thermal cycles and the rate of temperature changing speed in the thermal cycling have an important influence on TSDB process. Meanwhile, reasonable technological parameters chosen from theoretical analysis is in good agreement with those obtained from experimental results. 展开更多
关键词 TSDB eutectoid steel phase transformation SUPERPLASTICITY diffusion bonding theoretical model
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