As a leading project of Beijing's visionary endeavor to construct a"City of Museums"and establish the Grand Canal Cultural Belt,the Grand Canal Museum of Beijing also an emblematic item fostering coordin...As a leading project of Beijing's visionary endeavor to construct a"City of Museums"and establish the Grand Canal Cultural Belt,the Grand Canal Museum of Beijing also an emblematic item fostering coordinated development between Beijing,Tianjin,and Hebei Province.It is an intelligent comprehensive museum that integrates the functions of exhibition,social education,cultural protection and conservation,collection and storage.展开更多
David’s Story by Zoë Wicomb addresses the complexities of representing female suffering and the limitations of traditional historical narratives in capturing the experiences of marginalized bodies.It challenges ...David’s Story by Zoë Wicomb addresses the complexities of representing female suffering and the limitations of traditional historical narratives in capturing the experiences of marginalized bodies.It challenges the grand narratives of national history by emphasizing the indispensable role of women’s experiences.Through characters like Dulcie and Rachael,Wicomb portrays the female body as a site of resistance and resilience,highlighting the need for more nuanced and inclusive ways of documenting history.Underscoring the inexpressibility of trauma and the limitations of language and representation,the novel self-reflexively acknowledges its own aporia of completing the narrative,embodying the ongoing struggle to capture the full breadth of human experience.展开更多
The book initiates by portraying Africa,introducing its physical features and endowments,and providing a concise historical perspective that highlights Africa as the initial home of the human species.Subsequently,the ...The book initiates by portraying Africa,introducing its physical features and endowments,and providing a concise historical perspective that highlights Africa as the initial home of the human species.Subsequently,the book explores another epoch in Africa’s self-consciousness,focusing on the Pan-Africanism in the middle of the 20th century-the time when Africa had been greatly subjected to imperialism and colonialism,which plunged it into great destitution.展开更多
On May 26th,the China Cardiovascular Health Index 2023 was grandly released at the opening ceremony of the 17th Oriental Congress of Cardiology.The China Cardiovascular Health Index(CHI)is not only the first medical i...On May 26th,the China Cardiovascular Health Index 2023 was grandly released at the opening ceremony of the 17th Oriental Congress of Cardiology.The China Cardiovascular Health Index(CHI)is not only the first medical index-type indicator reflecting and measuring the status of cardiovascular diseases and treatment in our country,but also the world's first comprehensive index assessment of three-dimensional scanning for cardiovascular disease prevention and control at a national level.It holds a milestone significance for thedevelopmenttof cardiovascular disease prevention and treatment.展开更多
Grand canonical Monte Carlo simulation(GCMCs)is utilized for studying hydrogen storage gravimetric density by pha-graphene at different metal densities,temperatures and pressures.It is demonstrated that the optimum ad...Grand canonical Monte Carlo simulation(GCMCs)is utilized for studying hydrogen storage gravimetric density by pha-graphene at different metal densities,temperatures and pressures.It is demonstrated that the optimum adsorbent location for Li atoms is the center of the seven-membered ring of pha-graphene.The binding energy of Li-decorated phagraphene is larger than the cohesive energy of Li atoms,implying that Li can be distributed on the surface of pha-graphene without forming metal clusters.We fitted the force field parameters of Li and C atoms at different positions and performed GCMCs to study the absorption capacity of H_(2).The capacity of hydrogen storage was studied by the differing density of Li decoration.The maximum hydrogen storage capacity of 4Li-decorated pha-graphene was 15.88 wt%at 77 K and100 bar.The enthalpy values of adsorption at the three densities are in the ideal range of 15 kJ·mol^(-1)-25 kJ·mol^(-1).The GCMC results at different pressures and temperatures show that with the increase in Li decorative density,the hydrogen storage gravimetric ratio of pha-graphene decreases but can reach the 2025 US Department of Energy's standard(5.5 wt%).Therefore,pha-graphene is considered to be a potential hydrogen storage material.展开更多
Introduction: Grand multiparity is a known risk factor for maternal and fetal complications. Materials and Methods: We carried out a cross-sectional descriptive study on the delivery of grand multiparas at the materni...Introduction: Grand multiparity is a known risk factor for maternal and fetal complications. Materials and Methods: We carried out a cross-sectional descriptive study on the delivery of grand multiparas at the maternity of the regional hospital annex of Ayos, a semi-rural locality in the Center region of Cameroon. The study covered the period from January 2012 through December 2020, and the objective was to assess the frequency, the determinants and the outcome of delivery in grand multiparas. Results: We recorded 1384 deliveries and enrolled 137 cases of delivery of grand multiparas. This gives a frequency of grand multipara delivery of 9.89%. The mean age of the women was 34.96 ± 4.45 years. Married parturients accounted for 65% of the cases and 16.8% were HIV positive. Delivery occurred at term in 89.9%. In 35.8%, no antenatal consultation was done. The use of the partograph during labor was reported in 11.7%. Per vaginal delivery was noted in 88.3%, emergency cesarean in 10.2% and elective cesarean in 1.5%. The most frequent maternal complications included post-partum hemorrhage (19.9%), genital tract tears (12.4%), endometritis (9.5%) and surgical wound infection (8.7%). No maternal death was recorded. The mean birth weight of the newborns was 3336.8 ± 550 g. Fetal complications were mostly represented by neonatal infection (20.1%), perinatal death (7.9%) and neonatal asphyxia (9.5%). Conclusion: The frequency of grand multiparous delivery in the semi-rural locality of Ayos, Cameroon, was 9.89%. The mean age of parturients was 38.96 years and the proportion of vaginal delivery was 88.3%.展开更多
This paper attempts to propose a grand unified guiding principle of gauge fields from the mathematical and physical picture of fiber bundles: it is believed that our universe may have more fundamental interactions tha...This paper attempts to propose a grand unified guiding principle of gauge fields from the mathematical and physical picture of fiber bundles: it is believed that our universe may have more fundamental interactions than the four fundamental interactions, and the gauge fields of these fundamental interactions are just a unified gauge potential on the fiber bundle manifold or the components connected to the bottom manifold, that is, our universe;these components can meet the transformation of gauge potential, and even can be transformed from a fundamental interaction gauge potential to another fundamental interaction gauge potential, and can be summarized into a unified equation, namely the expression of the generalized gauge equation, corresponding to the gauge transformation invariance;so gauge transformation invariance is a necessary condition to unify field theory, but quantization of field is not a necessary condition;the four (or more) fundamental interaction fields of the universe are unified into a universal gauge field defined by the connection of the principal fiber bundle on the cosmic base manifold.展开更多
Perceive a new tendency,see a new future,take advantage of new technologies and lead a new wave!From Mar.23rd-25th,the“2023 China Surfactant Industry Conference”and“2023 China International Surfactant Industry Expo...Perceive a new tendency,see a new future,take advantage of new technologies and lead a new wave!From Mar.23rd-25th,the“2023 China Surfactant Industry Conference”and“2023 China International Surfactant Industry Expo”were held fervently at Guangzhou Nanfeng Langham Hotel.This grand event was sponsored by China Research Institute of Daily Chemical Industry,undertaken by China Daily Chemical Industry Information Center and Surfactant&Detergent Industry Productivity Promotion Center.展开更多
Polish composer Chopin’s“Andante Spianato Et Grand Polonaise Brillante,Op.22”,composed in the 19th century,has distinctive features from compositional techniques to acoustic characteristics,and has very unique musi...Polish composer Chopin’s“Andante Spianato Et Grand Polonaise Brillante,Op.22”,composed in the 19th century,has distinctive features from compositional techniques to acoustic characteristics,and has very unique musical connotations,especially the often-mentioned national and melancholic features in Chopin’s music.Based on the research plan,this paper aims at exploring the nationalism and tragic content in Chopin’s works and further exploring the potential emotional and spiritual core of Chopin’s compositions through the study of his socio-psychological situation and his unique style of compositional techniques.展开更多
On February 3,the 2023"Happy Chinese New Year"Float Parade and Square Celebration greeted the public in Port Louis,Mauritius.On the afternoon of that day,the streets of Port Louis were crowded with people bu...On February 3,the 2023"Happy Chinese New Year"Float Parade and Square Celebration greeted the public in Port Louis,Mauritius.On the afternoon of that day,the streets of Port Louis were crowded with people bustling with floats and flags flying.The grandly dressed people presented smile,with the streets filled with the joy of Chinese New Year.展开更多
Guided by the ternary leadership theory from the perspective of social psychology,this paper explores the impacts of authoritarian,benevolent,and moral leadership on the top design of the Grand Canal of China in terms...Guided by the ternary leadership theory from the perspective of social psychology,this paper explores the impacts of authoritarian,benevolent,and moral leadership on the top design of the Grand Canal of China in terms of its water management practice,while providing reference for resolving the“Matteo Ricci Puzzle”.The research findings are threefold:first,authoritarian as it is,the central government of China formulates relevant laws and regulations to provide legal system insurance for the construction of the Grand Canal Cultural Belt,thus providing the blueprint for constructing the“bright cultural belt,green ecological belt and colorful tourism belt of the Grand Canal”.Second,led by the Central Government,sticking to benevolent and moral leadership,China advocates scientific water management concepts and methods,and gives long-term and comprehensive care to the well-being of the people along the banks of the Grand Canal.Finally,the top-level design of the Grand Canal of China is based on the ternary leadership theory rooted in social psychology and has formulated a set of properly-scheduled,reasonably-coordinated,and flexibly-operated management system for the fundamental interests of the people and long-term goals of the country.展开更多
During the 3rd Belt and Road Forum for International Cooperation,the Children's Chorus of Xiaohuang Village Primary School from the hometown of Grand Song of the Dong Ethnic Group in Guizhou sang for guests at hom...During the 3rd Belt and Road Forum for International Cooperation,the Children's Chorus of Xiaohuang Village Primary School from the hometown of Grand Song of the Dong Ethnic Group in Guizhou sang for guests at home and abroad at China National Arts and Crafts Museum and China Intangible Cultural Heritage Museum(CTCM).The pure and beautiful voice won the praise of the foreign guests and the attention of allwalks oflife.展开更多
The Grand Shangri-La(GSL) region has strong international tourist appeal. GSL has considerable international eco-tourist potential as well as being attractive for leisure, vacation, health, explorative, and scientific...The Grand Shangri-La(GSL) region has strong international tourist appeal. GSL has considerable international eco-tourist potential as well as being attractive for leisure, vacation, health, explorative, and scientific research activities in addition to high-end tourism experiences. These factors could promote the development of its regional tourism. GSL has been identified as a key area for tourism development in China. In this study, we investigated tourism climate conditions in GSL from 1980 to 2016 using a tourism climate index(TCI). We found that through global warming, the number of annual and monthly good-weather days, as assessed with the TCI, showed an increase over most of GSL;that trend was especially true for very good, excellent, and ideal days. The optimal travel period was May–October. We obtained the same result using cluster heat maps, in which we categorized 31 studied meteorological stations into eight types. However, heavy rainfall tended to occur during that optimal period, and it was concentrated at certain times. The annual total number of comfortable days greater than 300 was mainly located in southern GSL. We observed significant correlations between monthly and annual excellent and ideal days with latitude and elevation;in particular, we identified a significant nonlinear correlation between excellent(and ideal) days and elevation.展开更多
The adsorption behavior of benzene and propylene in zeolite ZSM-5 was studied by Grand Canonical Monte Carlo(GCMC) simulations. It could be found that benzene and propylene molecules showed different adsorption beha...The adsorption behavior of benzene and propylene in zeolite ZSM-5 was studied by Grand Canonical Monte Carlo(GCMC) simulations. It could be found that benzene and propylene molecules showed different adsorption behavior in the zeolite cavities. The loadings of propylene were significantly larger than those of benzene at 100 kPa. From the figures of potential energy distribution, the potential energy of benzene/zeolite was more negative than that of propylene/zeolite, so benzene could be adsorbed more stably than propylene. When the temperature was in- creased from 298 to 443 K at 100 kPa, the loading ofpropylene was reduced from 99 to 82 molecules, whereas that of benzene changed little. When benzene and propylene were adsorbed in zeolite simultaneously, the competitive adsorption of them occurred; therefore, the potential energy distribution could be changed significantly. Besides, the adsorption isotherms of benzene and propylene in ZSM-5 at 298 and 443 K were simulated. The results exhibit that the different factors influenced the molecular adsorption at various temperatures and pressures, leading to the diffe- rent rules for the adsorption of benzene and propylene molecules in the zeolite. At a low pressure, the unfavorable energy of propylene/zeolite and the "commensurate freezing" phenomenon of benzene would make the loadings of itself higher than those of propylene. When pressure was higher than 5 kPa, the adsorption of benzene in ZSM-5 would nearly reach saturation.展开更多
The diffusion and adsorption behaviors of benzene and propylene in zeolites MFI, MWW and BEA have been studied by molecular dynamics(MD) and grand canonical Monte Carlo(GCMC) simulations. The diffusion coefficient...The diffusion and adsorption behaviors of benzene and propylene in zeolites MFI, MWW and BEA have been studied by molecular dynamics(MD) and grand canonical Monte Carlo(GCMC) simulations. The diffusion coefficients of benzene and propylene in MFI, MWW and BEA zeolites were calculated by simulating the mean-square displacements(MSD) at 298 and 600 K. Benzene and propylene showed the different adsorption rules in the channels of the three zeolites. For propylene, the molecular loadings decreased in the order: BEA(linear channel)〉BEA (tortuous channel)〉MFI(linear channel)〉MWW(12-membered rings, 12MR channel)〉MFI(tortuous channel)〉MWW (10-membered rings, 10MR channel); for benzene, the molecular loadings decreased in the order: BEA(linear chan-nel)〉BEA(tortuous channel)〉MWW(12MR channel)〉MFI(linear channel)〉MFI(tortuous channel)〉MWW(10MR channel). Besides, the adsorption isotherms of benzene and propylene in the three zeolites at 298 and 443 K were simulated. The results show that the different factors influenced the molecular adsorption at various temperatures and pressures, leading to the different rules for the adsorption of benzene and propylene molecules in the zeolites. At a low pressure, the unfavorable energy would make the loadings of propylene lower than those of benzene. When pressure was higher than 0.25 kPa, the adsorption of benzene in MFI would nearly reach saturation.展开更多
文摘As a leading project of Beijing's visionary endeavor to construct a"City of Museums"and establish the Grand Canal Cultural Belt,the Grand Canal Museum of Beijing also an emblematic item fostering coordinated development between Beijing,Tianjin,and Hebei Province.It is an intelligent comprehensive museum that integrates the functions of exhibition,social education,cultural protection and conservation,collection and storage.
基金This work was supported by Humanities and Social Sciences Fund of Ministry of Education of China(No.19XJA7520012020)by National Social Science Fund of China(No.20BWW069).
文摘David’s Story by Zoë Wicomb addresses the complexities of representing female suffering and the limitations of traditional historical narratives in capturing the experiences of marginalized bodies.It challenges the grand narratives of national history by emphasizing the indispensable role of women’s experiences.Through characters like Dulcie and Rachael,Wicomb portrays the female body as a site of resistance and resilience,highlighting the need for more nuanced and inclusive ways of documenting history.Underscoring the inexpressibility of trauma and the limitations of language and representation,the novel self-reflexively acknowledges its own aporia of completing the narrative,embodying the ongoing struggle to capture the full breadth of human experience.
文摘The book initiates by portraying Africa,introducing its physical features and endowments,and providing a concise historical perspective that highlights Africa as the initial home of the human species.Subsequently,the book explores another epoch in Africa’s self-consciousness,focusing on the Pan-Africanism in the middle of the 20th century-the time when Africa had been greatly subjected to imperialism and colonialism,which plunged it into great destitution.
文摘On May 26th,the China Cardiovascular Health Index 2023 was grandly released at the opening ceremony of the 17th Oriental Congress of Cardiology.The China Cardiovascular Health Index(CHI)is not only the first medical index-type indicator reflecting and measuring the status of cardiovascular diseases and treatment in our country,but also the world's first comprehensive index assessment of three-dimensional scanning for cardiovascular disease prevention and control at a national level.It holds a milestone significance for thedevelopmenttof cardiovascular disease prevention and treatment.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11904175,11804169,and 11804165)the Graduate Innovation Project of Jiangsu Province,China(Grant No.KYCX210700)。
文摘Grand canonical Monte Carlo simulation(GCMCs)is utilized for studying hydrogen storage gravimetric density by pha-graphene at different metal densities,temperatures and pressures.It is demonstrated that the optimum adsorbent location for Li atoms is the center of the seven-membered ring of pha-graphene.The binding energy of Li-decorated phagraphene is larger than the cohesive energy of Li atoms,implying that Li can be distributed on the surface of pha-graphene without forming metal clusters.We fitted the force field parameters of Li and C atoms at different positions and performed GCMCs to study the absorption capacity of H_(2).The capacity of hydrogen storage was studied by the differing density of Li decoration.The maximum hydrogen storage capacity of 4Li-decorated pha-graphene was 15.88 wt%at 77 K and100 bar.The enthalpy values of adsorption at the three densities are in the ideal range of 15 kJ·mol^(-1)-25 kJ·mol^(-1).The GCMC results at different pressures and temperatures show that with the increase in Li decorative density,the hydrogen storage gravimetric ratio of pha-graphene decreases but can reach the 2025 US Department of Energy's standard(5.5 wt%).Therefore,pha-graphene is considered to be a potential hydrogen storage material.
文摘Introduction: Grand multiparity is a known risk factor for maternal and fetal complications. Materials and Methods: We carried out a cross-sectional descriptive study on the delivery of grand multiparas at the maternity of the regional hospital annex of Ayos, a semi-rural locality in the Center region of Cameroon. The study covered the period from January 2012 through December 2020, and the objective was to assess the frequency, the determinants and the outcome of delivery in grand multiparas. Results: We recorded 1384 deliveries and enrolled 137 cases of delivery of grand multiparas. This gives a frequency of grand multipara delivery of 9.89%. The mean age of the women was 34.96 ± 4.45 years. Married parturients accounted for 65% of the cases and 16.8% were HIV positive. Delivery occurred at term in 89.9%. In 35.8%, no antenatal consultation was done. The use of the partograph during labor was reported in 11.7%. Per vaginal delivery was noted in 88.3%, emergency cesarean in 10.2% and elective cesarean in 1.5%. The most frequent maternal complications included post-partum hemorrhage (19.9%), genital tract tears (12.4%), endometritis (9.5%) and surgical wound infection (8.7%). No maternal death was recorded. The mean birth weight of the newborns was 3336.8 ± 550 g. Fetal complications were mostly represented by neonatal infection (20.1%), perinatal death (7.9%) and neonatal asphyxia (9.5%). Conclusion: The frequency of grand multiparous delivery in the semi-rural locality of Ayos, Cameroon, was 9.89%. The mean age of parturients was 38.96 years and the proportion of vaginal delivery was 88.3%.
文摘This paper attempts to propose a grand unified guiding principle of gauge fields from the mathematical and physical picture of fiber bundles: it is believed that our universe may have more fundamental interactions than the four fundamental interactions, and the gauge fields of these fundamental interactions are just a unified gauge potential on the fiber bundle manifold or the components connected to the bottom manifold, that is, our universe;these components can meet the transformation of gauge potential, and even can be transformed from a fundamental interaction gauge potential to another fundamental interaction gauge potential, and can be summarized into a unified equation, namely the expression of the generalized gauge equation, corresponding to the gauge transformation invariance;so gauge transformation invariance is a necessary condition to unify field theory, but quantization of field is not a necessary condition;the four (or more) fundamental interaction fields of the universe are unified into a universal gauge field defined by the connection of the principal fiber bundle on the cosmic base manifold.
文摘Perceive a new tendency,see a new future,take advantage of new technologies and lead a new wave!From Mar.23rd-25th,the“2023 China Surfactant Industry Conference”and“2023 China International Surfactant Industry Expo”were held fervently at Guangzhou Nanfeng Langham Hotel.This grand event was sponsored by China Research Institute of Daily Chemical Industry,undertaken by China Daily Chemical Industry Information Center and Surfactant&Detergent Industry Productivity Promotion Center.
文摘Polish composer Chopin’s“Andante Spianato Et Grand Polonaise Brillante,Op.22”,composed in the 19th century,has distinctive features from compositional techniques to acoustic characteristics,and has very unique musical connotations,especially the often-mentioned national and melancholic features in Chopin’s music.Based on the research plan,this paper aims at exploring the nationalism and tragic content in Chopin’s works and further exploring the potential emotional and spiritual core of Chopin’s compositions through the study of his socio-psychological situation and his unique style of compositional techniques.
文摘On February 3,the 2023"Happy Chinese New Year"Float Parade and Square Celebration greeted the public in Port Louis,Mauritius.On the afternoon of that day,the streets of Port Louis were crowded with people bustling with floats and flags flying.The grandly dressed people presented smile,with the streets filled with the joy of Chinese New Year.
基金the research funding from the National Planning Office of Philosophy and Social Science Grant of P.R.China(18BGJ086).
文摘Guided by the ternary leadership theory from the perspective of social psychology,this paper explores the impacts of authoritarian,benevolent,and moral leadership on the top design of the Grand Canal of China in terms of its water management practice,while providing reference for resolving the“Matteo Ricci Puzzle”.The research findings are threefold:first,authoritarian as it is,the central government of China formulates relevant laws and regulations to provide legal system insurance for the construction of the Grand Canal Cultural Belt,thus providing the blueprint for constructing the“bright cultural belt,green ecological belt and colorful tourism belt of the Grand Canal”.Second,led by the Central Government,sticking to benevolent and moral leadership,China advocates scientific water management concepts and methods,and gives long-term and comprehensive care to the well-being of the people along the banks of the Grand Canal.Finally,the top-level design of the Grand Canal of China is based on the ternary leadership theory rooted in social psychology and has formulated a set of properly-scheduled,reasonably-coordinated,and flexibly-operated management system for the fundamental interests of the people and long-term goals of the country.
文摘During the 3rd Belt and Road Forum for International Cooperation,the Children's Chorus of Xiaohuang Village Primary School from the hometown of Grand Song of the Dong Ethnic Group in Guizhou sang for guests at home and abroad at China National Arts and Crafts Museum and China Intangible Cultural Heritage Museum(CTCM).The pure and beautiful voice won the praise of the foreign guests and the attention of allwalks oflife.
基金supported by the National Natural Science Foundation of China (Grant No. 41571516, 41471448)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA19040503, XDA19040504)
文摘The Grand Shangri-La(GSL) region has strong international tourist appeal. GSL has considerable international eco-tourist potential as well as being attractive for leisure, vacation, health, explorative, and scientific research activities in addition to high-end tourism experiences. These factors could promote the development of its regional tourism. GSL has been identified as a key area for tourism development in China. In this study, we investigated tourism climate conditions in GSL from 1980 to 2016 using a tourism climate index(TCI). We found that through global warming, the number of annual and monthly good-weather days, as assessed with the TCI, showed an increase over most of GSL;that trend was especially true for very good, excellent, and ideal days. The optimal travel period was May–October. We obtained the same result using cluster heat maps, in which we categorized 31 studied meteorological stations into eight types. However, heavy rainfall tended to occur during that optimal period, and it was concentrated at certain times. The annual total number of comfortable days greater than 300 was mainly located in southern GSL. We observed significant correlations between monthly and annual excellent and ideal days with latitude and elevation;in particular, we identified a significant nonlinear correlation between excellent(and ideal) days and elevation.
基金Supported by the National Natural Science Foundation of China(Nos.20576012 and 20625621)
文摘The adsorption behavior of benzene and propylene in zeolite ZSM-5 was studied by Grand Canonical Monte Carlo(GCMC) simulations. It could be found that benzene and propylene molecules showed different adsorption behavior in the zeolite cavities. The loadings of propylene were significantly larger than those of benzene at 100 kPa. From the figures of potential energy distribution, the potential energy of benzene/zeolite was more negative than that of propylene/zeolite, so benzene could be adsorbed more stably than propylene. When the temperature was in- creased from 298 to 443 K at 100 kPa, the loading ofpropylene was reduced from 99 to 82 molecules, whereas that of benzene changed little. When benzene and propylene were adsorbed in zeolite simultaneously, the competitive adsorption of them occurred; therefore, the potential energy distribution could be changed significantly. Besides, the adsorption isotherms of benzene and propylene in ZSM-5 at 298 and 443 K were simulated. The results exhibit that the different factors influenced the molecular adsorption at various temperatures and pressures, leading to the diffe- rent rules for the adsorption of benzene and propylene molecules in the zeolite. At a low pressure, the unfavorable energy of propylene/zeolite and the "commensurate freezing" phenomenon of benzene would make the loadings of itself higher than those of propylene. When pressure was higher than 5 kPa, the adsorption of benzene in ZSM-5 would nearly reach saturation.
基金Supported by the National Natural Science Foundation of China(No.20576012)the Doctoral Fund of Qingdao University of Science and Technology China(No. 0022430)
文摘The diffusion and adsorption behaviors of benzene and propylene in zeolites MFI, MWW and BEA have been studied by molecular dynamics(MD) and grand canonical Monte Carlo(GCMC) simulations. The diffusion coefficients of benzene and propylene in MFI, MWW and BEA zeolites were calculated by simulating the mean-square displacements(MSD) at 298 and 600 K. Benzene and propylene showed the different adsorption rules in the channels of the three zeolites. For propylene, the molecular loadings decreased in the order: BEA(linear channel)〉BEA (tortuous channel)〉MFI(linear channel)〉MWW(12-membered rings, 12MR channel)〉MFI(tortuous channel)〉MWW (10-membered rings, 10MR channel); for benzene, the molecular loadings decreased in the order: BEA(linear chan-nel)〉BEA(tortuous channel)〉MWW(12MR channel)〉MFI(linear channel)〉MFI(tortuous channel)〉MWW(10MR channel). Besides, the adsorption isotherms of benzene and propylene in the three zeolites at 298 and 443 K were simulated. The results show that the different factors influenced the molecular adsorption at various temperatures and pressures, leading to the different rules for the adsorption of benzene and propylene molecules in the zeolites. At a low pressure, the unfavorable energy would make the loadings of propylene lower than those of benzene. When pressure was higher than 0.25 kPa, the adsorption of benzene in MFI would nearly reach saturation.