Most current catalyst preparation methods cause pollution to air, water and land with the use of hazardous chemicals, lengthy operation time, high energy input and excessive water usage. The development of green catal...Most current catalyst preparation methods cause pollution to air, water and land with the use of hazardous chemicals, lengthy operation time, high energy input and excessive water usage. The development of green catalyst preparation is necessary to prevent and eliminate waste from each step of the catalyst preparation. We summarize recent progress in the application of cold plasmas for green catalyst preparation. Cold plasma preparation can reduce the catalyst size, improve the dispersion and enhance catalyst-support interaction with the use of less or no hazardous chemicals. These improvements also lead to the enhancement of catalyst activity and stability. An alternative room temperature electron reduction with a non-hydrogen plasma as an electron source was developed for the reduction of noble metal ions in which no hazardous chemical reducing agent or hydrogen was needed. This creates many opportunities for the development of supported catalysts with heat sensitive substrates, including metal organic frameworks (MOFs), covalent organic framework(COFs), high surface area carbon, peptide, DNA, proteins and others. A novel floating metal catalyst on a water(or solution) surface has been established. Template removal using low temperature cold plasmas also leads to the formation of high surface area porous materials with characteristics that are normally only obtainable with high temperature calcination, but sintering can be avoided. Micro combustion has been developed for the removal of carbon template using cold plasma. This is promising for preparing many structured oxides in a simple way with no use of auxiliary chemicals. Many opportunities exist for the use of cold plasmas to make multi-metallic oxides. Some future development ideas are addressed.展开更多
Confucianism (especially its teaching theory) is the core of Chinese traditional culture with Confucius as its representative. It has played an indispensable role in the development of Chinese culture. It is the spi...Confucianism (especially its teaching theory) is the core of Chinese traditional culture with Confucius as its representative. It has played an indispensable role in the development of Chinese culture. It is the spiritual pillar of Chinese sustainable development. There are no others that can compare with its teaching method and art. The famous "heuristic teaching theory" is one of its greatest inventions. But many people think that it is Socrates invention. In fact, Socrates "elicitation teaching theory" was invented far later than that of Confucius. This paper aims at investigating of these two theories.展开更多
A two-dimensional mathematical model based on volume-of-fluid method is proposed to investigate the heat transfer,fluidflow and keyhole dynamics during electron beam welding(EBW)on20mm-thick2219aluminum alloy plate.In...A two-dimensional mathematical model based on volume-of-fluid method is proposed to investigate the heat transfer,fluidflow and keyhole dynamics during electron beam welding(EBW)on20mm-thick2219aluminum alloy plate.In the model,anadaptive heat source model tracking keyhole depth is employed to simulate the heating process of electron beam.Heat and masstransport of different vortexes induced by surface tension,thermo-capillary force,recoil pressure,hydrostatic pressure and thermalbuoyancy is coupled with keyhole evolution.A series of physical phenomena involving keyhole drilling,collapse,reopening,quasi-stability,backfilling and the coupled thermal field are analyzed systematically.The results indicate that the decreased heat fluxof beam in depth can decelerate the keyholing velocity of recoil pressure and promote the quasi-steady state.Before and close to thisstate,the keyhole collapses and complicates the fluid transport of vortexes.Finally,all simulation results are validated againstexperiments.展开更多
In recent years there has been a proliferation of studies demonstrating the value of teaching abroad as much for its benefits for the training and professional development of these teachers,as for its impact and benef...In recent years there has been a proliferation of studies demonstrating the value of teaching abroad as much for its benefits for the training and professional development of these teachers,as for its impact and beneficial effects on students.This article uses transformative learning as a theoretical framework to interpret the achievements associated with the experience of teaching abroad,and to identify and analyze different motivational factors,adjustments,changes,challenges,and perspectives of Chinese teachers linked to a Confucius Institute in Spain,through a qualitative analysis of narratives elicited through in-depth interviews and focus groups.It highlights the role and potential of the transnational,intercultural experience of these teachers as authentic actors in the part played by the Confucius Institutes in language teaching and the promotion of Chinese culture,indicating many issues including language difficulties,professional adjustment,ideas about education,beliefs of teachers and the management of the program.展开更多
The Chinese Dream, adopted by General Secretary Xi Jinping, was used and spread in China. It is about Chinese prosperity, collective effort, socialism and national glory. It is also about the welfare, wellbeing, and q...The Chinese Dream, adopted by General Secretary Xi Jinping, was used and spread in China. It is about Chinese prosperity, collective effort, socialism and national glory. It is also about the welfare, wellbeing, and quality of life of every Chinese. Academics in higher education in China are facing changes both across the globe and in China, they must take the challenges. This paper does research on wellbeing of the academics from the aspects of the definition of wellbeing, the situation both in the world and in China, the Chinese concept of happiness, the possible influence of Confucius moral standards on wellbeing of Chinese. This paper may help school leaders implement policies that foster effective work environment in the new era in China.展开更多
The frequent suicides Dutch act, thought-provoking, the reason is the lack of Shuness. To Confucius Memorial, friends, starting from the thought, research what is Shuness, seek Shuness for college students lack of urg...The frequent suicides Dutch act, thought-provoking, the reason is the lack of Shuness. To Confucius Memorial, friends, starting from the thought, research what is Shuness, seek Shuness for college students lack of urgency, to answer today's society Shuness remodeling and personality of College students.展开更多
The effect of porosity on compressive,bending,and tensile properties of the porous tantalum scaffolds fabricated by electron beam powder bed fusion(EB-PBF)was investigated.The porous tantalum scaffolds with porosity f...The effect of porosity on compressive,bending,and tensile properties of the porous tantalum scaffolds fabricated by electron beam powder bed fusion(EB-PBF)was investigated.The porous tantalum scaffolds with porosity from 69%to 77.8%were obtained by varying the designed porosity and adjusting the processing parameters.It is found that the pores and unfused powder decrease with the increase of deposited energy density.The decrease of porosity leads to an improvement in mechanical properties.The relevancy between compressive/bending/tensile yield strength and relative density can be described appropriately by exponential model,while the relationship between elastic modulus and relative density is in good agreement with the Gibson-Ashby model.All the porous tantalum scaffolds exhibit good ductility in compressive,bending and tensile tests.No fragmentation of struts is observed during the compression process,but cracks are formed on the strut surface after 90°bending,mainly due to the high sensibility to defects caused by the oxide.展开更多
The Schroedinger equation involving the phenomenon of the localization and entanglement for an exciton in a quantum dot molecule by an ac electric field is analytically investigated. New exact series solutions for the...The Schroedinger equation involving the phenomenon of the localization and entanglement for an exciton in a quantum dot molecule by an ac electric field is analytically investigated. New exact series solutions for the Schroedinger equation have been obtained for the first time. The analytical expressions can further describe the dynamical behaviors of an interacting electron-hole pair in a double coupled quantum dot molecule under an ac electric field accurately.展开更多
Western heuristic teaching method was originated from Socrates who initiated the teaching mode of "teachers ask, students answer". A distinctive feature of this mode was that teachers were the decisive factor in the...Western heuristic teaching method was originated from Socrates who initiated the teaching mode of "teachers ask, students answer". A distinctive feature of this mode was that teachers were the decisive factor in the process of teaching and learning, who raised the questions at the very beginning and gave conclusions in the end. On the contrary, oriental style of heuristic teaching method based itself on the principle that students put forward their puzzles and then asked the teachers for advice. This paper will reconsider Confucius enlightening reflection and probe into how to develop students' ability of thinking by questioning strategies in the heuristic teaching methodology.展开更多
As a developing Non-profit Organization (NPO) system for the learning and diffusion of Chinese language and culture around the globe, the Confucius Institute network is becoming more and more important for China's ...As a developing Non-profit Organization (NPO) system for the learning and diffusion of Chinese language and culture around the globe, the Confucius Institute network is becoming more and more important for China's presence and influence in a diversified arena of world cultures. While this network is being enlarged and improved with the Chinese govemment's persistent backing, it is, however, recognized that the influence and efficiency of the institutes are still limited. It might not be essential whether people come primarily as serious language learners, but necessarily, the platform has to be attractive enough for a considerable proportion of users to stick on, making the Confucius Institute System a sustainable cultural service provider. Within the background of information society, the Intemet, mobile service, digital broadcasting, and other types of new media would act as an important effort to help Confucius Institutes to improve the capabilities of interacting with users, offering users with abundant media-rich content, and minimizing users' inconvenience by enhancing users' experience, lowering travel and time cost, and easily providing multi-lingual support. In this paper, we take the platform of Confucius Institute Online (http://www.chinese.cn, the official Intemet portal of the Confucius Institute network) as a case of actuality to analyze how the Confucius Institute system could utilize the communication capability of new media to enrich, enlarge, and enhance the diffusion of Chinese culture and language. Advantages and deficiencies of the planning, design, and layout of the portal's functionality and views are presented, upon which a number of strategic suggestions are raised, for the sake of further improvement of Confucius Institute's efficiency in cultural diffusion and sustainable development.展开更多
Although national learning, i.e., traditional Chinese learning, has been affected by the onslaught of Western learning, its pulse still beats strongly. Its intellectual essence consists in the Chinese emphasis on a co...Although national learning, i.e., traditional Chinese learning, has been affected by the onslaught of Western learning, its pulse still beats strongly. Its intellectual essence consists in the Chinese emphasis on a complementary "relationship" of differences that takes shape in the course of production and life and on the harmonious "whole," together with Chinese efforts to control their own destiny by virtue of this relationship and this whole. The "learning" in national learning revolves around man and is vividly manifested in the Confucian concept of "benevolence" or human-heartedness (ren 仁). If one were to say that Chinese modernization is nothing other than the Chinese nation's "self-'transformation and transcendence under the impact of external forces, then it is national learning that can provide significant intellectual resources for modern Chinese to go about their lives and work through the transmission and extension of the idea of "benevolence." However, this can only happen if culture and scholarship are fully "self-aware."展开更多
Understanding the adsorption and desorption behavior of methane has received considerable attention since it is one of the crucial aspects of the exploitation of shale gas.Unexpectedly,obvious hysteresis is observed f...Understanding the adsorption and desorption behavior of methane has received considerable attention since it is one of the crucial aspects of the exploitation of shale gas.Unexpectedly,obvious hysteresis is observed from the ideally reversible physical sorption of methane in some experiments.However,the underlying mechanism still remains an open problem.In this study,Monte Carlo(MC) and molecular dynamics(MD) simulations are carried out to explore the molecular mechanisms of adsorption/desorption hysteresis.First,a detailed analysis about the capillary condensation of methane in micropores is presented.The influence of pore width,surface strength,and temperature on the hysteresis loop is further investigated.It is found that a disappearance of hysteresis occurs above a temperature threshold.Combined with the phase diagram of methane,we explicitly point out that capillary condensation is inapplicable for the hysteresis of shale gas under normal temperature conditions.Second,a new mechanism,variation of pore throat size,is proposed and studied.For methane to pass through the throat,a certain energy is required due to the repulsive interaction.The required energy increases with shrinkage of the throat,such that the originally adsorbed methane cannot escape through the narrowed throat.These trapped methane molecules account for the hysteresis.Furthermore,the hysteresis loop is found to increase with the increasing pressure and decreasing temperature.We suggest that the variation of pore throat size can explain the adsorption/desorption hysteresis of shale gas.Our conclusions and findings are of great significance for guiding the efficient exploitation of shale gas.展开更多
A simple and rapid approach for the electrochemical synthesis of Ag nanoparticles-coated gold nanoporous film (AgGNF) on a gold substrate was reported. The solid gold electrode (SGE) was directly anodized under a high...A simple and rapid approach for the electrochemical synthesis of Ag nanoparticles-coated gold nanoporous film (AgGNF) on a gold substrate was reported. The solid gold electrode (SGE) was directly anodized under a high potential of 5 V, and then reduced to obtain gold nanoporous film (AuNF) by freshly prepared ascorbic acid. The Ag nanoparticles (AgNPs) were grown on the AuNF electrode by potential-step electrodeposition. The resulting AgGNF composites electrodes were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy and cyclic voltammetry (CV). As-prepared AgGNF electrode was used as a kind of superior sensor for Cr(VI) detection, which exhibited better electrocatalytic behavior than those of AuNF and SGE under identical conditions. Such a designed AgGNF nanocomposites electrode showed outstanding sensitivity (about 0.15 nA/ppb) and favorable reproducibility for Cr(VI) detection. The dependence of reduction current on Cr(VI) concentration is linear from 2 to 370 ppb with a low detection limit of 0.65 ppb. Interferences from other heavy metals ions (Cr3+, Cu2+, Pb2+, As3+ and Hg2+) associated with Cr(VI) analysis could be effectively diminished. The present method proves to be rapid, reliable, sensitive and low-cost.展开更多
基金supported by the National Natural Science Foundation of China(20990223 and 21476157)~~
文摘Most current catalyst preparation methods cause pollution to air, water and land with the use of hazardous chemicals, lengthy operation time, high energy input and excessive water usage. The development of green catalyst preparation is necessary to prevent and eliminate waste from each step of the catalyst preparation. We summarize recent progress in the application of cold plasmas for green catalyst preparation. Cold plasma preparation can reduce the catalyst size, improve the dispersion and enhance catalyst-support interaction with the use of less or no hazardous chemicals. These improvements also lead to the enhancement of catalyst activity and stability. An alternative room temperature electron reduction with a non-hydrogen plasma as an electron source was developed for the reduction of noble metal ions in which no hazardous chemical reducing agent or hydrogen was needed. This creates many opportunities for the development of supported catalysts with heat sensitive substrates, including metal organic frameworks (MOFs), covalent organic framework(COFs), high surface area carbon, peptide, DNA, proteins and others. A novel floating metal catalyst on a water(or solution) surface has been established. Template removal using low temperature cold plasmas also leads to the formation of high surface area porous materials with characteristics that are normally only obtainable with high temperature calcination, but sintering can be avoided. Micro combustion has been developed for the removal of carbon template using cold plasma. This is promising for preparing many structured oxides in a simple way with no use of auxiliary chemicals. Many opportunities exist for the use of cold plasmas to make multi-metallic oxides. Some future development ideas are addressed.
文摘Confucianism (especially its teaching theory) is the core of Chinese traditional culture with Confucius as its representative. It has played an indispensable role in the development of Chinese culture. It is the spiritual pillar of Chinese sustainable development. There are no others that can compare with its teaching method and art. The famous "heuristic teaching theory" is one of its greatest inventions. But many people think that it is Socrates invention. In fact, Socrates "elicitation teaching theory" was invented far later than that of Confucius. This paper aims at investigating of these two theories.
文摘A two-dimensional mathematical model based on volume-of-fluid method is proposed to investigate the heat transfer,fluidflow and keyhole dynamics during electron beam welding(EBW)on20mm-thick2219aluminum alloy plate.In the model,anadaptive heat source model tracking keyhole depth is employed to simulate the heating process of electron beam.Heat and masstransport of different vortexes induced by surface tension,thermo-capillary force,recoil pressure,hydrostatic pressure and thermalbuoyancy is coupled with keyhole evolution.A series of physical phenomena involving keyhole drilling,collapse,reopening,quasi-stability,backfilling and the coupled thermal field are analyzed systematically.The results indicate that the decreased heat fluxof beam in depth can decelerate the keyholing velocity of recoil pressure and promote the quasi-steady state.Before and close to thisstate,the keyhole collapses and complicates the fluid transport of vortexes.Finally,all simulation results are validated againstexperiments.
文摘In recent years there has been a proliferation of studies demonstrating the value of teaching abroad as much for its benefits for the training and professional development of these teachers,as for its impact and beneficial effects on students.This article uses transformative learning as a theoretical framework to interpret the achievements associated with the experience of teaching abroad,and to identify and analyze different motivational factors,adjustments,changes,challenges,and perspectives of Chinese teachers linked to a Confucius Institute in Spain,through a qualitative analysis of narratives elicited through in-depth interviews and focus groups.It highlights the role and potential of the transnational,intercultural experience of these teachers as authentic actors in the part played by the Confucius Institutes in language teaching and the promotion of Chinese culture,indicating many issues including language difficulties,professional adjustment,ideas about education,beliefs of teachers and the management of the program.
文摘The Chinese Dream, adopted by General Secretary Xi Jinping, was used and spread in China. It is about Chinese prosperity, collective effort, socialism and national glory. It is also about the welfare, wellbeing, and quality of life of every Chinese. Academics in higher education in China are facing changes both across the globe and in China, they must take the challenges. This paper does research on wellbeing of the academics from the aspects of the definition of wellbeing, the situation both in the world and in China, the Chinese concept of happiness, the possible influence of Confucius moral standards on wellbeing of Chinese. This paper may help school leaders implement policies that foster effective work environment in the new era in China.
文摘The frequent suicides Dutch act, thought-provoking, the reason is the lack of Shuness. To Confucius Memorial, friends, starting from the thought, research what is Shuness, seek Shuness for college students lack of urgency, to answer today's society Shuness remodeling and personality of College students.
基金supported by the Key R&D Program of Guangdong Province,China(Nos.2019B090904001,2018B090906003)。
文摘The effect of porosity on compressive,bending,and tensile properties of the porous tantalum scaffolds fabricated by electron beam powder bed fusion(EB-PBF)was investigated.The porous tantalum scaffolds with porosity from 69%to 77.8%were obtained by varying the designed porosity and adjusting the processing parameters.It is found that the pores and unfused powder decrease with the increase of deposited energy density.The decrease of porosity leads to an improvement in mechanical properties.The relevancy between compressive/bending/tensile yield strength and relative density can be described appropriately by exponential model,while the relationship between elastic modulus and relative density is in good agreement with the Gibson-Ashby model.All the porous tantalum scaffolds exhibit good ductility in compressive,bending and tensile tests.No fragmentation of struts is observed during the compression process,but cracks are formed on the strut surface after 90°bending,mainly due to the high sensibility to defects caused by the oxide.
基金The project partially supported by National Natural Science Foundation of China under Grant No.10247008 and the Science Foundation of Northwest Normal University of China under Grant No. NWNU-KJCXGC-02-04
文摘The Schroedinger equation involving the phenomenon of the localization and entanglement for an exciton in a quantum dot molecule by an ac electric field is analytically investigated. New exact series solutions for the Schroedinger equation have been obtained for the first time. The analytical expressions can further describe the dynamical behaviors of an interacting electron-hole pair in a double coupled quantum dot molecule under an ac electric field accurately.
文摘Western heuristic teaching method was originated from Socrates who initiated the teaching mode of "teachers ask, students answer". A distinctive feature of this mode was that teachers were the decisive factor in the process of teaching and learning, who raised the questions at the very beginning and gave conclusions in the end. On the contrary, oriental style of heuristic teaching method based itself on the principle that students put forward their puzzles and then asked the teachers for advice. This paper will reconsider Confucius enlightening reflection and probe into how to develop students' ability of thinking by questioning strategies in the heuristic teaching methodology.
文摘As a developing Non-profit Organization (NPO) system for the learning and diffusion of Chinese language and culture around the globe, the Confucius Institute network is becoming more and more important for China's presence and influence in a diversified arena of world cultures. While this network is being enlarged and improved with the Chinese govemment's persistent backing, it is, however, recognized that the influence and efficiency of the institutes are still limited. It might not be essential whether people come primarily as serious language learners, but necessarily, the platform has to be attractive enough for a considerable proportion of users to stick on, making the Confucius Institute System a sustainable cultural service provider. Within the background of information society, the Intemet, mobile service, digital broadcasting, and other types of new media would act as an important effort to help Confucius Institutes to improve the capabilities of interacting with users, offering users with abundant media-rich content, and minimizing users' inconvenience by enhancing users' experience, lowering travel and time cost, and easily providing multi-lingual support. In this paper, we take the platform of Confucius Institute Online (http://www.chinese.cn, the official Intemet portal of the Confucius Institute network) as a case of actuality to analyze how the Confucius Institute system could utilize the communication capability of new media to enrich, enlarge, and enhance the diffusion of Chinese culture and language. Advantages and deficiencies of the planning, design, and layout of the portal's functionality and views are presented, upon which a number of strategic suggestions are raised, for the sake of further improvement of Confucius Institute's efficiency in cultural diffusion and sustainable development.
文摘Although national learning, i.e., traditional Chinese learning, has been affected by the onslaught of Western learning, its pulse still beats strongly. Its intellectual essence consists in the Chinese emphasis on a complementary "relationship" of differences that takes shape in the course of production and life and on the harmonious "whole," together with Chinese efforts to control their own destiny by virtue of this relationship and this whole. The "learning" in national learning revolves around man and is vividly manifested in the Confucian concept of "benevolence" or human-heartedness (ren 仁). If one were to say that Chinese modernization is nothing other than the Chinese nation's "self-'transformation and transcendence under the impact of external forces, then it is national learning that can provide significant intellectual resources for modern Chinese to go about their lives and work through the transmission and extension of the idea of "benevolence." However, this can only happen if culture and scholarship are fully "self-aware."
基金supported by the National Natural Science Foundation of China(Grant Nos.11525211,and 11472263)the CNPC-CAS Strategic Cooperation Research Program(Grant No.2015A-4812)+1 种基金Anhui Provincial Natural Science Foundation(Grant No.1408085J08)the Fundamental Research Funds for the Central Universities of China
文摘Understanding the adsorption and desorption behavior of methane has received considerable attention since it is one of the crucial aspects of the exploitation of shale gas.Unexpectedly,obvious hysteresis is observed from the ideally reversible physical sorption of methane in some experiments.However,the underlying mechanism still remains an open problem.In this study,Monte Carlo(MC) and molecular dynamics(MD) simulations are carried out to explore the molecular mechanisms of adsorption/desorption hysteresis.First,a detailed analysis about the capillary condensation of methane in micropores is presented.The influence of pore width,surface strength,and temperature on the hysteresis loop is further investigated.It is found that a disappearance of hysteresis occurs above a temperature threshold.Combined with the phase diagram of methane,we explicitly point out that capillary condensation is inapplicable for the hysteresis of shale gas under normal temperature conditions.Second,a new mechanism,variation of pore throat size,is proposed and studied.For methane to pass through the throat,a certain energy is required due to the repulsive interaction.The required energy increases with shrinkage of the throat,such that the originally adsorbed methane cannot escape through the narrowed throat.These trapped methane molecules account for the hysteresis.Furthermore,the hysteresis loop is found to increase with the increasing pressure and decreasing temperature.We suggest that the variation of pore throat size can explain the adsorption/desorption hysteresis of shale gas.Our conclusions and findings are of great significance for guiding the efficient exploitation of shale gas.
基金supported by the National Natural Science Foundation of China (21005014)the Foundation of Donghua University (113-10-0044029)
文摘A simple and rapid approach for the electrochemical synthesis of Ag nanoparticles-coated gold nanoporous film (AgGNF) on a gold substrate was reported. The solid gold electrode (SGE) was directly anodized under a high potential of 5 V, and then reduced to obtain gold nanoporous film (AuNF) by freshly prepared ascorbic acid. The Ag nanoparticles (AgNPs) were grown on the AuNF electrode by potential-step electrodeposition. The resulting AgGNF composites electrodes were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy and cyclic voltammetry (CV). As-prepared AgGNF electrode was used as a kind of superior sensor for Cr(VI) detection, which exhibited better electrocatalytic behavior than those of AuNF and SGE under identical conditions. Such a designed AgGNF nanocomposites electrode showed outstanding sensitivity (about 0.15 nA/ppb) and favorable reproducibility for Cr(VI) detection. The dependence of reduction current on Cr(VI) concentration is linear from 2 to 370 ppb with a low detection limit of 0.65 ppb. Interferences from other heavy metals ions (Cr3+, Cu2+, Pb2+, As3+ and Hg2+) associated with Cr(VI) analysis could be effectively diminished. The present method proves to be rapid, reliable, sensitive and low-cost.