As a potential adsorption material,it is still a challenge for activated carbon fiber(ACF)in efficient adsorption of ethanol due to its nonpolar surface,which is mainly emitted from the grain drying industry.This stud...As a potential adsorption material,it is still a challenge for activated carbon fiber(ACF)in efficient adsorption of ethanol due to its nonpolar surface,which is mainly emitted from the grain drying industry.This study prepared surface polarity-modified ACF using the heteroatom doping method.The modified ACF possessed a richer array of strongly polar oxygen/nitrogen-containing functional groups(primarily phenolic hydroxyl and lactone groups),a larger specific surface are1,and a more developed micropore structure.The adsorption capacities of ethanol for O-ACF and N-ACF were 4.110 mmol/g and 1.698 mmol/g,respectively,which were 11.3 times and 4.7 times those of unmodified ACF.This was a significant improvement over our previous work(0.363 mmol/g).The improvement of adsorption capacity for the N-ACF was mainly due to the higher specific surface are1,greater number of micropores(more adsorption sites)and abundant existence of defects,whereas,for O-ACF,the improvement mainly relied on the abundant presence of oxygen-containing functional groups on the surface.However,water had a negative effect on the adsorption of ethanol for the modified ACF due to competitive adsorption and the disappearance of capillary condensation.It was further revealed that the adsorption process of ethanol and water was quite different.It obeyed the linear driving force(LDF)model for ethanol adsorption,however,the intraparticle diffusion(IPD)model for water adsorption.展开更多
Theoretical calculations serve as an effective method for determining plasma temperatures within planetary atmospheres.To simulate plasma temperature,a comprehensive implementation of the energy equation is used,which...Theoretical calculations serve as an effective method for determining plasma temperatures within planetary atmospheres.To simulate plasma temperature,a comprehensive implementation of the energy equation is used,which is governed by five terms:conductivity,heating,cooling,adiabatic expansion,and advection.The derivations mentioned are strongly dependent on the collision cross section between electrons and other particles(e.g.,neutrals,ions).It is notable that the momentum transfer cross sections between electrons and neutrals have been updated in recent decades.However,the widely used momentum average collision cross sections between electrons and neutrals,derived from the momentum transfer cross sections,are collected in studies dating back nearly half a century.Therefore,it becomes imperative to revise the momentum average collision cross sections relevant to astrophysical contexts,based on the latest studies.In this study,we summarize the momentum average collision cross sections of 13 species common in planetary atmospheres:H,H_(2),He,O,CH_(4),H_(2)O,CO,N_(2),O_(2),Ar,CO_(2),N_(2)O,and NO_(2).All results are derived from the latest studies concerning the electron-neutral collision cross section and are compared with previous studies.Furthermore,we present a comparison of the derived total electron-neutral collision frequency at Mars between this study and previous studies.Prominent differences in the total electron-neutral collision frequency between this and prior studies support the significance of updating the momentum average collision cross section between electrons and neutrals in studying the planetary atmospheres.展开更多
The present study proposed the"re-flipped classroom"teaching mode taking the course Principles of Residential District Planning as an example.Using the Small Private Online Courses(SPOCs)and Massive Open Onl...The present study proposed the"re-flipped classroom"teaching mode taking the course Principles of Residential District Planning as an example.Using the Small Private Online Courses(SPOCs)and Massive Open Online Courses(MOOCs)of the iCourse platform,with the aid of the mind mapping technology,the complex content is visualized to the information that can be easily accepted by the brain,to improve the efficiency of thinking problems and apply theories to practical teaching.The results indicate that the teaching mode combined with mind mapping technology has strong appeal,can improve teacher-student interaction,and effectively improve the teaching effects.Finally,it came up with recommendations including attaching importance to the"re-flipped classroom"teaching mode,integrating teaching methods,and using online platform resources.It is concluded that the research of teaching mode has important theoretical and practical significance for ensuring the teaching quality.展开更多
Implementing innovation and entrepreneurship education by combining with professional education in universities and colleges is an important measure to promote higher-quality employment and entrepreneurship of the gra...Implementing innovation and entrepreneurship education by combining with professional education in universities and colleges is an important measure to promote higher-quality employment and entrepreneurship of the graduates. The problems existing in the fusing teaching of computer application technology and innovation and entrepreneurship education are analyzed in this paper. By taking Hunan Applied Technology University as an example and in view of the existing problems, the mode of reform driven by "four wheels","professional talent training scheme by integrating optimization, innovation and entrepreneurship","implementing the specific teaching by integrating imovation,entrepreneurship and professional education","building many forms and university-enterprise cooperation platforms for innovation and entrepreneurship" and "setting up reasonable management and incentive mechanism for teachers and students" are proposed, to realize the dynamic integration of professional education and innovation and entrepreneurship education for the specialty of computer application technology.展开更多
The same floor drainage refers to sanitary wares in the washing room, to be specific, the drainage pipe （sewage and branch pipes respectively） which can be into other houses without going through floors! This techno...The same floor drainage refers to sanitary wares in the washing room, to be specific, the drainage pipe （sewage and branch pipes respectively） which can be into other houses without going through floors! This technology has many advantages, like easy to construct and install at the same floor on one hand; on the other hand, when sewage or waste reach the top compared with the same kind drainage systems and other drainage methods, it can smoothly enter the main pipe （the chief vertical one）. Moreover, once there is any situation needing dredge and cleaning, this problem can be solved at the same floor without interrupting the lives of other families. Last but not the least, it is so convenient to create a clean and tidy washing room. The branch pipe without being through floors is the very reason to solve the problem of surface condensation relative to sewage pipe in the rainy days, which correspondingly increases the hcight of head room indoor, is more favorable for fire prevention and much easier to keep smooth pipe flow.展开更多
With the rapid development of China＇s economy, the entire social requires the safety, reliability and automation of power supply and distribution system must be improved. Therefore, extensive application of PLC techn...With the rapid development of China＇s economy, the entire social requires the safety, reliability and automation of power supply and distribution system must be improved. Therefore, extensive application of PLC technology in power supply and distribution system has great significance to ensure normal social life and production, so as to realize the entire national economy sustained and healthy development. This paper briefly introduces the PLC technology, and with practice elaborates the applications of control technology based on PLC in power supply and distribution system fi：om the reform of low-voltage distribution system, automation management and relay protection of power supply and distribution system etc.展开更多
This study is dedicated to exploring the role of scientific research team construction and collaborative management mechanisms in applied undergraduate universities in promoting diversified talent training and collabo...This study is dedicated to exploring the role of scientific research team construction and collaborative management mechanisms in applied undergraduate universities in promoting diversified talent training and collaborative innovation models.By forming an interdisciplinary scientific research team and recording in detail the team’s performance,problems encountered,and solutions during the collaborative innovation process,the study found that interdisciplinary team construction significantly improved scientific research timeliness,which was 29.33%higher than that of traditional single-disciplinary teams.Therefore,the construction of interdisciplinary scientific research teams and collaborative management mechanisms are effective ways for applied undergraduate universities to promote diversified talent training and collaborative innovation.展开更多
High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increa...High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increased conduction loss often leads to a significant decline in electromagnetic wave absorp-tion(EMWA)performance at elevated temperatures,which severely restricts their practical application.In this study,we propose a novel approach for efficient electromagnetic wave absorption across a wide temperature range using reduced graphene oxide(RGO)/epoxy resin(EP)metacomposites that integrate both electromagnetic parameters and metamaterial design concepts.Due to the discrete distribution of the units,electromagnetic waves can more easily penetrate the interior of materials,thereby exhibiting stable microwave absorption(MA)performance and impedance-matching characteristics suitable across a wide temperature range.Consequently,exceptional MA properties can be achieved within the tem-perature range from 298 to 473 K.Furthermore,by carefully controlling the structural parameters in RGO metacomposites,both the resonant frequency and effective absorption bandwidth(EAB)can be optimized based on precise manipulation of equivalent electromagnetic parameters.This study not only provides an effective approach for the rational design of MA performance but also offers novel insights into achieving super metamaterials with outstanding performance across a wide temperature spectrum.展开更多
In dynamic scenarios,visual simultaneous localization and mapping(SLAM)algorithms often incorrectly incorporate dynamic points during camera pose computation,leading to reduced accuracy and robustness.This paper prese...In dynamic scenarios,visual simultaneous localization and mapping(SLAM)algorithms often incorrectly incorporate dynamic points during camera pose computation,leading to reduced accuracy and robustness.This paper presents a dynamic SLAM algorithm that leverages object detection and regional dynamic probability.Firstly,a parallel thread employs the YOLOX object detectionmodel to gather 2D semantic information and compensate for missed detections.Next,an improved K-means++clustering algorithm clusters bounding box regions,adaptively determining the threshold for extracting dynamic object contours as dynamic points change.This process divides the image into low dynamic,suspicious dynamic,and high dynamic regions.In the tracking thread,the dynamic point removal module assigns dynamic probability weights to the feature points in these regions.Combined with geometric methods,it detects and removes the dynamic points.The final evaluation on the public TUM RGB-D dataset shows that the proposed dynamic SLAM algorithm surpasses most existing SLAM algorithms,providing better pose estimation accuracy and robustness in dynamic environments.展开更多
Hard carbon (HC) has been considered as promising anode material for sodium-ion batteries (SIBs).The optimization of hard carbon’s microstructure and solid electrolyte interface (SEI) property are demonstrated effect...Hard carbon (HC) has been considered as promising anode material for sodium-ion batteries (SIBs).The optimization of hard carbon’s microstructure and solid electrolyte interface (SEI) property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly desirable.Herein,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage sites.In-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy (FTIR/EIS) and X-ray photoelectron spectroscopy (XPS) analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate performance.As a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling performance.In general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.展开更多
Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as...Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as the strongly enhanced synergistic interactions between Pt and Co atoms,the obtained Pt-on-Co/C400 catalysts exhib-ited excellent catalytic activity toward the hydrolysis of ammonia borane with an extremely high turnover frequency(TOF)value of 3022 min^(-1)at 303 K.Durability test indicated that the obtained Pt-on-Co/C400 catalysts possessed high catalytic stability,and there were no changes in the catalyst structures and catalytic activities after 10 cycles.展开更多
As an essential candidate for environment-friendly luminescent quantum dots(QDs),CuInS-based QDs have attracted more attention in recent years.However,several drawbacks still hamper their industrial applications,such ...As an essential candidate for environment-friendly luminescent quantum dots(QDs),CuInS-based QDs have attracted more attention in recent years.However,several drawbacks still hamper their industrial applications,such as lower photoluminescence quantum yield(PLQY),complex synthetic pathways,uncontrollable emission spectra,and insufficient photostability.In this study,CuInZnS@ZnS core/shell QDs was prepared via a one-pot/three-step synthetic scheme with accurate and tunable control of PL spectra.Then their ensemble spectroscopic properties during nucleation formation,alloying,and ZnS shell growth processes were systematically investigated.PL peaks of these QDs can be precisely manipulated from 530 to 850 nm by controlling the stoichiometric ratio of Cu/In,Zn^(2+)doping and ZnS shell growth.In particular,CuInZnS@ZnS QDs possess a significantly long emission lifetime(up to 750 ns),high PLQY(up to 85%),and excellent crystallinity.Their spectroscopic evolution is well validated by Cu-deficient related intragap emission model.By controlling the stoichiometric ratio of Cu/In,two distinct Cu-deficient related emission pathways are established based on the differing oxidation states of Cu defects.Therefore,this work provides deeper insights for fabricating high luminescent ternary or quaternary-alloyed QDs.展开更多
Changes to the microstructure of a hard carbon(HC)and its solid electrolyte interface(SEI)can be effective in improving the electrode kinetics.However,achieving fast charging using a simple and inexpensive strategy wi...Changes to the microstructure of a hard carbon(HC)and its solid electrolyte interface(SEI)can be effective in improving the electrode kinetics.However,achieving fast charging using a simple and inexpensive strategy without sacrificing its initial Coulombic efficiency remains a challenge in sodium ion batteries.A simple liquid-phase coating approach has been used to generate a pitch-derived soft carbon layer on the HC surface,and its effect on the porosity of HC and SEI chemistry has been studied.A variety of structural characterizations show a soft carbon coating can increase the defect and ultra-micropore contents.The increase in ultra-micropore comes from both the soft carbon coatings and the larger pores within the HC that are partially filled by pitch,which provides more Na+storage sites.In-situ FTIR/EIS and ex-situ XPS showed that the soft carbon coating induced the formation of thinner SEI that is richer in NaF from the electrolyte,which stabilized the interface and promoted the charge transfer process.As a result,the anode produced fastcharging(329.8 mAh g^(−1)at 30 mA g^(−1)and 198.6 mAh g^(−1)at 300 mA g^(−1))and had a better cycling performance(a high capacity retention of 81.4%after 100 cycles at 150 mA g^(−1)).This work reveals the critical role of coating layer in changing the pore structure,SEI chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced fast charging capability.展开更多
With the advancement of modern technology and the continuous development of science,research into flapping wing aircraft is becoming increasingly sophisticated.Addressing issues such as the large wingspan and heavy ma...With the advancement of modern technology and the continuous development of science,research into flapping wing aircraft is becoming increasingly sophisticated.Addressing issues such as the large wingspan and heavy mass of existing bionic butterfly aircraft,this paper proposes the design of a lightweight lithium battery power supply,a chip integrated into a small circuit board,and a reference to the natural characteristics of butterfly wings.The wings are simulated using 0.125 mm polyethylene terephthalate(PET)film to replicate their movement.The driving structure employs a double motor and a four-bar mechanism to achieve natural and smooth wing vibrations.The control system features a lightweight motor,battery,and a high-performance low-power microcontroller for precise control.Using 3D printing technology,a lightweight design is realized,successfully simulating the structure and movement characteristics of a specific butterfly,demonstrating the principles of mechatronics.Furthermore,the design process incorporates multidisciplinary knowledge,and a workshop combining competitive discipline events with innovation and entrepreneurship has been established.This initiative fosters the deep integration of innovation and entrepreneurship education with professional training,effectively cultivating application-oriented technical talents.展开更多
The highly photocatalytic conversion of CO_(2)into valuable products is a promising method for mitigating the global greenhouse effect and increasing the energy supply.However,the utilization of electron-deficient act...The highly photocatalytic conversion of CO_(2)into valuable products is a promising method for mitigating the global greenhouse effect and increasing the energy supply.However,the utilization of electron-deficient active sites to activate CO_(2)leads to lower photocatalytic efficiency and selectivity.One effective strategy to improve CO_(2)photoreduction performance is making precise adjustments to the electronic structure of the photocatalyst.Herein,the defective TiO_(2)modified with Cu,Ba,and CuBa metal sites is synthesized via a simple photo-deposition method and applied for photoreduction of CO_(2).Among the prepared catalysts,Cu1Ba_(3)/TiO_(2)-SBO(TiO_(2)-SBO:TiO_(2)with surface and bulk oxygen vacancies)has been demonstrated to possess excellent photocatalytic conversion of CO_(2),with the activity levels of the CO and CH_(4) that are 8 and 6 times higher than the bare TiO_(2)-SBO,and the electron selectivity of CO is up to 53%.The results reveal that oxygen vacancies and CuBa bimetallic sites have a synergistic ability to facilitate the separation of photogenerated carriers.Furthermore,the electron-donor Ba metal enables modulation of the electronic structure of Cu co-catalysts,generating electron-rich Cu metal sites that accelerate the activation of CO_(2).Meanwhile,the theoretical calculations prove that the Cu1Ba_(3)/TiO_(2)-SBO has the stronger CO_(2)adsorption energy,and its strengthened binding of^(*)COOH and the markedly reduced formation energy of CO and^(*)CO intermediates boost the conversion of COOH to CO and enhance the selectivity of CO.Thereby,the defective TiO_(2)modified with CuBa bimetal represents a more effective measure for CO_(2)reduction into valuable products.展开更多
Soil salinization is a prominent global environmental issue that considerably affects the sustainable development of agriculture worldwide.Maize,a key crop integral to the global agricultural economy,is especially sus...Soil salinization is a prominent global environmental issue that considerably affects the sustainable development of agriculture worldwide.Maize,a key crop integral to the global agricultural economy,is especially susceptible to the detrimental impacts of salt stress,which can impede its growth and development from the germination phase through to the seedling stage.Soil salinity tends to escalate due to improper irrigation methods,particularly in arid and semi-arid environments.Consequently,it is essential to evaluate potential genotypes and select those with high salt tolerance.In this study,39 popcorn kernel genotypes were examined under varying salinity levels(0,100,and 200 mM NaCl).Notable declines in seedling growth and significant differences in stress responses were recorded in relation to salinity levels.The application of 200 mM NaCl was found to severely hinder the growth of sensitive species such as maize,adversely impacting both the germination rate and speed.Even when germination occurred,subsequent seedling development was stunted.Therefore,it is advisable to utilize salinity concentrations below 200 mM in research focused on seedling development stages.The assessment of genotypes for their adaptability to saline conditions indicated that genotypes 4,33,12,28,18,21,25,37,16,and 31 exhibited high salt tolerance,while genotypes 1,17,35,and 36 were identified as susceptible.It is recommended that the more resilient genotypes be utilized in regions affected by salt stress or incorporated into breeding programs.展开更多
Bean(Phaseolus vulgaris)is a globally important legume crop valued for its nutritional content and adaptability.Establishing a robust root system during early growth is critical for optimal nutrient uptake,shoot devel...Bean(Phaseolus vulgaris)is a globally important legume crop valued for its nutritional content and adaptability.Establishing a robust root system during early growth is critical for optimal nutrient uptake,shoot development,and increased resistance to biotic stress.This study evaluated the effects of exogenous indole-3-butyric acid(IBA)on root and shoot development in two bean cultivars,Onceler-98 and Topcu,during the seedling stage.IBA was applied at four concentrations:0(control),50,100,and 150μM.Morphological parameters measured included root length(RL),root fresh weight(RFW),root dry weight(RDW),root nodule number(RNN),shoot length(SL),shoot fresh weight(SFW),and shoot dry weight(SDW).The experiment followed a randomized complete block design with four replications.Significant(p≤0.05)and highly significant(p≤0.01)differences were observed across treatments and cultivars.The results indicated that Onceler-98 generally responded more favorably to IBA application,with optimal growth performance observed at 100μM.In contrast,Topcu was less responsive to IBA overall,and high concentrations-particularly 150μM-tended to suppress nodule formation.展开更多
BACKGROUND With the increasing global incidence of mental illness,depression has become a serious problem among college students.AIM To investigate the relationship between depression and its correlates in Chinese ado...BACKGROUND With the increasing global incidence of mental illness,depression has become a serious problem among college students.AIM To investigate the relationship between depression and its correlates in Chinese adolescents and to identify diagnostic predictors of depression,examine the effects of binge eating,physical activity,and body dissatisfaction on depression among college students and to determine a diagnostic cutoff value for depression based on body dissatisfaction.METHODS We conducted a cross-sectional survey of 1286 college students in South China.Physical activity level,depressive symptoms,and binge eating behavior were assessed using the Physical Activity Scale-3,Zung Self-Rating Depression Scale,and Dutch Eating Behavior Questionnaire,respectively.The absolute difference between actual body mass index(BMI)and ideal BMI was used to indicate the level of body dissatisfaction.Structural equation modeling(SEM)and receiver operating characteristic(ROC)curve analysis were used to examine the relationships between these variables and depression.RESULTS The findings showed that female college students reported higher levels of depression.Physical activity,body dissatisfaction,and binge eating behavior were significantly associated with depression.SEM revealed that body dissatisfaction played a mediating role.A body dissatisfaction score of 1.73 was identified as the diagnostic cutoff value for predicting depression,with an area under the ROC curve of 70.0%,providing a basis for targeted interventions.CONCLUSION This study demonstrated a significant positive correlation between body dissatisfaction and depression.Low levels of physical activity and binge eating behaviors were found to heighten the risk of depression.Therefore,promoting physical activity and healthy eating habits among adolescents is essential.Additionally,the identification of a diagnostic threshold for body dissatisfaction represents a novel finding with important implications for early screening.Future longitudinal studies are recommended to further refine this diagnostic criterion.展开更多
The increasing complexity of on-orbit tasks imposes great demands on the flexible operation of space robotic arms, prompting the development of space robots from single-arm manipulation to multi-arm collaboration. In ...The increasing complexity of on-orbit tasks imposes great demands on the flexible operation of space robotic arms, prompting the development of space robots from single-arm manipulation to multi-arm collaboration. In this paper, a combined approach of Learning from Demonstration (LfD) and Reinforcement Learning (RL) is proposed for space multi-arm collaborative skill learning. The combination effectively resolves the trade-off between learning efficiency and feasible solution in LfD, as well as the time-consuming pursuit of the optimal solution in RL. With the prior knowledge of LfD, space robotic arms can achieve efficient guided learning in high-dimensional state-action space. Specifically, an LfD approach with Probabilistic Movement Primitives (ProMP) is firstly utilized to encode and reproduce the demonstration actions, generating a distribution as the initialization of policy. Then in the RL stage, a Relative Entropy Policy Search (REPS) algorithm modified in continuous state-action space is employed for further policy improvement. More importantly, the learned behaviors can maintain and reflect the characteristics of demonstrations. In addition, a series of supplementary policy search mechanisms are designed to accelerate the exploration process. The effectiveness of the proposed method has been verified both theoretically and experimentally. Moreover, comparisons with state-of-the-art methods have confirmed the outperformance of the approach.展开更多
The Book of Songs is the first collection of poems in China,originally named Poetry,and is one of the Five Classics.Whether in terms of themes,thoughts and emotions,language skills,as well as in artistic images and ex...The Book of Songs is the first collection of poems in China,originally named Poetry,and is one of the Five Classics.Whether in terms of themes,thoughts and emotions,language skills,as well as in artistic images and expression methods,it has shown the great achievements of China’s earliest poetry works and has produced a profound influence on Chinese culture and literature.It not only has recorded the various aspects of the society of that time,but also opens the door to many literary studies.There is no need to argue about its status and significance.In the West,about twelve centuries after the creation of the first poem collected in The Book of Songs,there lived a literary theorist who has performed a great influence on western literature.He was Longinus,the author of On the Sublime.By comparing the aesthetic ideas of Longinus and the artistic characteristics of The Book of Songs,we are surprised to find that The Book of Songs is a paragon of the sublime described by Longinus.展开更多
基金supported by the National Key R&D Program of China(Nos.2022YFB4101500 and 2022YFE0209500)the National Natural Science Foundation of China(Nos.22276191 and 21976177)the Qinghai Province Air Pollution Assessment and Fine Management Support Project,and the University of Chinese Academy of Science.
文摘As a potential adsorption material,it is still a challenge for activated carbon fiber(ACF)in efficient adsorption of ethanol due to its nonpolar surface,which is mainly emitted from the grain drying industry.This study prepared surface polarity-modified ACF using the heteroatom doping method.The modified ACF possessed a richer array of strongly polar oxygen/nitrogen-containing functional groups(primarily phenolic hydroxyl and lactone groups),a larger specific surface are1,and a more developed micropore structure.The adsorption capacities of ethanol for O-ACF and N-ACF were 4.110 mmol/g and 1.698 mmol/g,respectively,which were 11.3 times and 4.7 times those of unmodified ACF.This was a significant improvement over our previous work(0.363 mmol/g).The improvement of adsorption capacity for the N-ACF was mainly due to the higher specific surface are1,greater number of micropores(more adsorption sites)and abundant existence of defects,whereas,for O-ACF,the improvement mainly relied on the abundant presence of oxygen-containing functional groups on the surface.However,water had a negative effect on the adsorption of ethanol for the modified ACF due to competitive adsorption and the disappearance of capillary condensation.It was further revealed that the adsorption process of ethanol and water was quite different.It obeyed the linear driving force(LDF)model for ethanol adsorption,however,the intraparticle diffusion(IPD)model for water adsorption.
基金the National Natural Science Foundation of China through Grants 42261160643,42441806,42241114,and 42304166supported by the open project funded by the Key Laboratory of Geospace Environment,Chinese Academy of Sciences,University of Science and Technology of China.
文摘Theoretical calculations serve as an effective method for determining plasma temperatures within planetary atmospheres.To simulate plasma temperature,a comprehensive implementation of the energy equation is used,which is governed by five terms:conductivity,heating,cooling,adiabatic expansion,and advection.The derivations mentioned are strongly dependent on the collision cross section between electrons and other particles(e.g.,neutrals,ions).It is notable that the momentum transfer cross sections between electrons and neutrals have been updated in recent decades.However,the widely used momentum average collision cross sections between electrons and neutrals,derived from the momentum transfer cross sections,are collected in studies dating back nearly half a century.Therefore,it becomes imperative to revise the momentum average collision cross sections relevant to astrophysical contexts,based on the latest studies.In this study,we summarize the momentum average collision cross sections of 13 species common in planetary atmospheres:H,H_(2),He,O,CH_(4),H_(2)O,CO,N_(2),O_(2),Ar,CO_(2),N_(2)O,and NO_(2).All results are derived from the latest studies concerning the electron-neutral collision cross section and are compared with previous studies.Furthermore,we present a comparison of the derived total electron-neutral collision frequency at Mars between this study and previous studies.Prominent differences in the total electron-neutral collision frequency between this and prior studies support the significance of updating the momentum average collision cross section between electrons and neutrals in studying the planetary atmospheres.
基金2018 University-level Teaching Reform Research Project of Jiangxi Normal University(JXSDJG1852).
文摘The present study proposed the"re-flipped classroom"teaching mode taking the course Principles of Residential District Planning as an example.Using the Small Private Online Courses(SPOCs)and Massive Open Online Courses(MOOCs)of the iCourse platform,with the aid of the mind mapping technology,the complex content is visualized to the information that can be easily accepted by the brain,to improve the efficiency of thinking problems and apply theories to practical teaching.The results indicate that the teaching mode combined with mind mapping technology has strong appeal,can improve teacher-student interaction,and effectively improve the teaching effects.Finally,it came up with recommendations including attaching importance to the"re-flipped classroom"teaching mode,integrating teaching methods,and using online platform resources.It is concluded that the research of teaching mode has important theoretical and practical significance for ensuring the teaching quality.
文摘Implementing innovation and entrepreneurship education by combining with professional education in universities and colleges is an important measure to promote higher-quality employment and entrepreneurship of the graduates. The problems existing in the fusing teaching of computer application technology and innovation and entrepreneurship education are analyzed in this paper. By taking Hunan Applied Technology University as an example and in view of the existing problems, the mode of reform driven by "four wheels","professional talent training scheme by integrating optimization, innovation and entrepreneurship","implementing the specific teaching by integrating imovation,entrepreneurship and professional education","building many forms and university-enterprise cooperation platforms for innovation and entrepreneurship" and "setting up reasonable management and incentive mechanism for teachers and students" are proposed, to realize the dynamic integration of professional education and innovation and entrepreneurship education for the specialty of computer application technology.
文摘The same floor drainage refers to sanitary wares in the washing room, to be specific, the drainage pipe （sewage and branch pipes respectively） which can be into other houses without going through floors! This technology has many advantages, like easy to construct and install at the same floor on one hand; on the other hand, when sewage or waste reach the top compared with the same kind drainage systems and other drainage methods, it can smoothly enter the main pipe （the chief vertical one）. Moreover, once there is any situation needing dredge and cleaning, this problem can be solved at the same floor without interrupting the lives of other families. Last but not the least, it is so convenient to create a clean and tidy washing room. The branch pipe without being through floors is the very reason to solve the problem of surface condensation relative to sewage pipe in the rainy days, which correspondingly increases the hcight of head room indoor, is more favorable for fire prevention and much easier to keep smooth pipe flow.
文摘With the rapid development of China＇s economy, the entire social requires the safety, reliability and automation of power supply and distribution system must be improved. Therefore, extensive application of PLC technology in power supply and distribution system has great significance to ensure normal social life and production, so as to realize the entire national economy sustained and healthy development. This paper briefly introduces the PLC technology, and with practice elaborates the applications of control technology based on PLC in power supply and distribution system fi：om the reform of low-voltage distribution system, automation management and relay protection of power supply and distribution system etc.
基金Research on Innovative Talent Cultivation in Mechanical Engineering Majors under the Background of Emerging Engineering Education(2023SJYB1493)Research and Practice on the Cultivation Mode of Innovative Ability of College Students from the Perspective of Integration of Specialty and Entrepreneurship(2023SJYB1501)Beijing Hopefound Group-Jiangsu Union Technical Institute-Targeted Talent Cultivation and Training Program(2024030732830)。
文摘This study is dedicated to exploring the role of scientific research team construction and collaborative management mechanisms in applied undergraduate universities in promoting diversified talent training and collaborative innovation models.By forming an interdisciplinary scientific research team and recording in detail the team’s performance,problems encountered,and solutions during the collaborative innovation process,the study found that interdisciplinary team construction significantly improved scientific research timeliness,which was 29.33%higher than that of traditional single-disciplinary teams.Therefore,the construction of interdisciplinary scientific research teams and collaborative management mechanisms are effective ways for applied undergraduate universities to promote diversified talent training and collaborative innovation.
基金supported by the National Nature Science Foundation of China(Nos.22305066 and 52372041).
文摘High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increased conduction loss often leads to a significant decline in electromagnetic wave absorp-tion(EMWA)performance at elevated temperatures,which severely restricts their practical application.In this study,we propose a novel approach for efficient electromagnetic wave absorption across a wide temperature range using reduced graphene oxide(RGO)/epoxy resin(EP)metacomposites that integrate both electromagnetic parameters and metamaterial design concepts.Due to the discrete distribution of the units,electromagnetic waves can more easily penetrate the interior of materials,thereby exhibiting stable microwave absorption(MA)performance and impedance-matching characteristics suitable across a wide temperature range.Consequently,exceptional MA properties can be achieved within the tem-perature range from 298 to 473 K.Furthermore,by carefully controlling the structural parameters in RGO metacomposites,both the resonant frequency and effective absorption bandwidth(EAB)can be optimized based on precise manipulation of equivalent electromagnetic parameters.This study not only provides an effective approach for the rational design of MA performance but also offers novel insights into achieving super metamaterials with outstanding performance across a wide temperature spectrum.
基金the National Natural Science Foundation of China(No.62063006)to the Guangxi Natural Science Foundation under Grant(Nos.2023GXNSFAA026025,AA24010001)+3 种基金to the Innovation Fund of Chinese Universities Industry-University-Research(ID:2023RY018)to the Special Guangxi Industry and Information Technology Department,Textile and Pharmaceutical Division(ID:2021 No.231)to the Special Research Project of Hechi University(ID:2021GCC028)to the Key Laboratory of AI and Information Processing,Education Department of Guangxi Zhuang Autonomous Region(Hechi University),No.2024GXZDSY009。
文摘In dynamic scenarios,visual simultaneous localization and mapping(SLAM)algorithms often incorrectly incorporate dynamic points during camera pose computation,leading to reduced accuracy and robustness.This paper presents a dynamic SLAM algorithm that leverages object detection and regional dynamic probability.Firstly,a parallel thread employs the YOLOX object detectionmodel to gather 2D semantic information and compensate for missed detections.Next,an improved K-means++clustering algorithm clusters bounding box regions,adaptively determining the threshold for extracting dynamic object contours as dynamic points change.This process divides the image into low dynamic,suspicious dynamic,and high dynamic regions.In the tracking thread,the dynamic point removal module assigns dynamic probability weights to the feature points in these regions.Combined with geometric methods,it detects and removes the dynamic points.The final evaluation on the public TUM RGB-D dataset shows that the proposed dynamic SLAM algorithm surpasses most existing SLAM algorithms,providing better pose estimation accuracy and robustness in dynamic environments.
基金National Key Research and Development Program of China (2022YFE0206300)National Natural Science Foundation of China (U21A2081,22075074, 22209047)+3 种基金Guangdong Basic and Applied Basic Research Foundation (2024A1515011620)Hunan Provincial Natural Science Foundation of China (2024JJ5068)Foundation of Yuelushan Center for Industrial Innovation (2023YCII0119)Student Innovation Training Program (S202410532594,S202410532357)。
文摘Hard carbon (HC) has been considered as promising anode material for sodium-ion batteries (SIBs).The optimization of hard carbon’s microstructure and solid electrolyte interface (SEI) property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly desirable.Herein,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage sites.In-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy (FTIR/EIS) and X-ray photoelectron spectroscopy (XPS) analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate performance.As a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling performance.In general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.
文摘Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as the strongly enhanced synergistic interactions between Pt and Co atoms,the obtained Pt-on-Co/C400 catalysts exhib-ited excellent catalytic activity toward the hydrolysis of ammonia borane with an extremely high turnover frequency(TOF)value of 3022 min^(-1)at 303 K.Durability test indicated that the obtained Pt-on-Co/C400 catalysts possessed high catalytic stability,and there were no changes in the catalyst structures and catalytic activities after 10 cycles.
基金Fund Project for Transformation of Scientific and Technological Achievements of Jiangsu Province of China(BA2023020)。
文摘As an essential candidate for environment-friendly luminescent quantum dots(QDs),CuInS-based QDs have attracted more attention in recent years.However,several drawbacks still hamper their industrial applications,such as lower photoluminescence quantum yield(PLQY),complex synthetic pathways,uncontrollable emission spectra,and insufficient photostability.In this study,CuInZnS@ZnS core/shell QDs was prepared via a one-pot/three-step synthetic scheme with accurate and tunable control of PL spectra.Then their ensemble spectroscopic properties during nucleation formation,alloying,and ZnS shell growth processes were systematically investigated.PL peaks of these QDs can be precisely manipulated from 530 to 850 nm by controlling the stoichiometric ratio of Cu/In,Zn^(2+)doping and ZnS shell growth.In particular,CuInZnS@ZnS QDs possess a significantly long emission lifetime(up to 750 ns),high PLQY(up to 85%),and excellent crystallinity.Their spectroscopic evolution is well validated by Cu-deficient related intragap emission model.By controlling the stoichiometric ratio of Cu/In,two distinct Cu-deficient related emission pathways are established based on the differing oxidation states of Cu defects.Therefore,this work provides deeper insights for fabricating high luminescent ternary or quaternary-alloyed QDs.
基金National Key Research and Development Program of China(2022YFE0206300)National Natural Science Foundation of China(U21A2081,22075074,22209047)+2 种基金Guangdong Basic and Applied Basic Research Foundation(2024A1515011620)Hunan Provincial Natural Science Foundation of China(2024JJ5068)Foundation of Yuelushan Center for Industrial Innovation(2023YCII0119)。
文摘Changes to the microstructure of a hard carbon(HC)and its solid electrolyte interface(SEI)can be effective in improving the electrode kinetics.However,achieving fast charging using a simple and inexpensive strategy without sacrificing its initial Coulombic efficiency remains a challenge in sodium ion batteries.A simple liquid-phase coating approach has been used to generate a pitch-derived soft carbon layer on the HC surface,and its effect on the porosity of HC and SEI chemistry has been studied.A variety of structural characterizations show a soft carbon coating can increase the defect and ultra-micropore contents.The increase in ultra-micropore comes from both the soft carbon coatings and the larger pores within the HC that are partially filled by pitch,which provides more Na+storage sites.In-situ FTIR/EIS and ex-situ XPS showed that the soft carbon coating induced the formation of thinner SEI that is richer in NaF from the electrolyte,which stabilized the interface and promoted the charge transfer process.As a result,the anode produced fastcharging(329.8 mAh g^(−1)at 30 mA g^(−1)and 198.6 mAh g^(−1)at 300 mA g^(−1))and had a better cycling performance(a high capacity retention of 81.4%after 100 cycles at 150 mA g^(−1)).This work reveals the critical role of coating layer in changing the pore structure,SEI chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced fast charging capability.
基金Innovation and Entrepreneurship Training Project for College Students in Hunan Province in 2024:Design of Small Bionic Butterfly Machine Under the Background of Innovation and Integration(Project No.S202413809022)2023 Innovation and Entrepreneurship Training Project of Hunan College Students:Tiger Butterfly—Bionic Manufacturing and Morphology Research(Project No.S202313809022)。
文摘With the advancement of modern technology and the continuous development of science,research into flapping wing aircraft is becoming increasingly sophisticated.Addressing issues such as the large wingspan and heavy mass of existing bionic butterfly aircraft,this paper proposes the design of a lightweight lithium battery power supply,a chip integrated into a small circuit board,and a reference to the natural characteristics of butterfly wings.The wings are simulated using 0.125 mm polyethylene terephthalate(PET)film to replicate their movement.The driving structure employs a double motor and a four-bar mechanism to achieve natural and smooth wing vibrations.The control system features a lightweight motor,battery,and a high-performance low-power microcontroller for precise control.Using 3D printing technology,a lightweight design is realized,successfully simulating the structure and movement characteristics of a specific butterfly,demonstrating the principles of mechatronics.Furthermore,the design process incorporates multidisciplinary knowledge,and a workshop combining competitive discipline events with innovation and entrepreneurship has been established.This initiative fosters the deep integration of innovation and entrepreneurship education with professional training,effectively cultivating application-oriented technical talents.
文摘The highly photocatalytic conversion of CO_(2)into valuable products is a promising method for mitigating the global greenhouse effect and increasing the energy supply.However,the utilization of electron-deficient active sites to activate CO_(2)leads to lower photocatalytic efficiency and selectivity.One effective strategy to improve CO_(2)photoreduction performance is making precise adjustments to the electronic structure of the photocatalyst.Herein,the defective TiO_(2)modified with Cu,Ba,and CuBa metal sites is synthesized via a simple photo-deposition method and applied for photoreduction of CO_(2).Among the prepared catalysts,Cu1Ba_(3)/TiO_(2)-SBO(TiO_(2)-SBO:TiO_(2)with surface and bulk oxygen vacancies)has been demonstrated to possess excellent photocatalytic conversion of CO_(2),with the activity levels of the CO and CH_(4) that are 8 and 6 times higher than the bare TiO_(2)-SBO,and the electron selectivity of CO is up to 53%.The results reveal that oxygen vacancies and CuBa bimetallic sites have a synergistic ability to facilitate the separation of photogenerated carriers.Furthermore,the electron-donor Ba metal enables modulation of the electronic structure of Cu co-catalysts,generating electron-rich Cu metal sites that accelerate the activation of CO_(2).Meanwhile,the theoretical calculations prove that the Cu1Ba_(3)/TiO_(2)-SBO has the stronger CO_(2)adsorption energy,and its strengthened binding of^(*)COOH and the markedly reduced formation energy of CO and^(*)CO intermediates boost the conversion of COOH to CO and enhance the selectivity of CO.Thereby,the defective TiO_(2)modified with CuBa bimetal represents a more effective measure for CO_(2)reduction into valuable products.
文摘Soil salinization is a prominent global environmental issue that considerably affects the sustainable development of agriculture worldwide.Maize,a key crop integral to the global agricultural economy,is especially susceptible to the detrimental impacts of salt stress,which can impede its growth and development from the germination phase through to the seedling stage.Soil salinity tends to escalate due to improper irrigation methods,particularly in arid and semi-arid environments.Consequently,it is essential to evaluate potential genotypes and select those with high salt tolerance.In this study,39 popcorn kernel genotypes were examined under varying salinity levels(0,100,and 200 mM NaCl).Notable declines in seedling growth and significant differences in stress responses were recorded in relation to salinity levels.The application of 200 mM NaCl was found to severely hinder the growth of sensitive species such as maize,adversely impacting both the germination rate and speed.Even when germination occurred,subsequent seedling development was stunted.Therefore,it is advisable to utilize salinity concentrations below 200 mM in research focused on seedling development stages.The assessment of genotypes for their adaptability to saline conditions indicated that genotypes 4,33,12,28,18,21,25,37,16,and 31 exhibited high salt tolerance,while genotypes 1,17,35,and 36 were identified as susceptible.It is recommended that the more resilient genotypes be utilized in regions affected by salt stress or incorporated into breeding programs.
文摘Bean(Phaseolus vulgaris)is a globally important legume crop valued for its nutritional content and adaptability.Establishing a robust root system during early growth is critical for optimal nutrient uptake,shoot development,and increased resistance to biotic stress.This study evaluated the effects of exogenous indole-3-butyric acid(IBA)on root and shoot development in two bean cultivars,Onceler-98 and Topcu,during the seedling stage.IBA was applied at four concentrations:0(control),50,100,and 150μM.Morphological parameters measured included root length(RL),root fresh weight(RFW),root dry weight(RDW),root nodule number(RNN),shoot length(SL),shoot fresh weight(SFW),and shoot dry weight(SDW).The experiment followed a randomized complete block design with four replications.Significant(p≤0.05)and highly significant(p≤0.01)differences were observed across treatments and cultivars.The results indicated that Onceler-98 generally responded more favorably to IBA application,with optimal growth performance observed at 100μM.In contrast,Topcu was less responsive to IBA overall,and high concentrations-particularly 150μM-tended to suppress nodule formation.
基金Supported by Starting Research Fund from the Gannan Medical University,No.QD202121。
文摘BACKGROUND With the increasing global incidence of mental illness,depression has become a serious problem among college students.AIM To investigate the relationship between depression and its correlates in Chinese adolescents and to identify diagnostic predictors of depression,examine the effects of binge eating,physical activity,and body dissatisfaction on depression among college students and to determine a diagnostic cutoff value for depression based on body dissatisfaction.METHODS We conducted a cross-sectional survey of 1286 college students in South China.Physical activity level,depressive symptoms,and binge eating behavior were assessed using the Physical Activity Scale-3,Zung Self-Rating Depression Scale,and Dutch Eating Behavior Questionnaire,respectively.The absolute difference between actual body mass index(BMI)and ideal BMI was used to indicate the level of body dissatisfaction.Structural equation modeling(SEM)and receiver operating characteristic(ROC)curve analysis were used to examine the relationships between these variables and depression.RESULTS The findings showed that female college students reported higher levels of depression.Physical activity,body dissatisfaction,and binge eating behavior were significantly associated with depression.SEM revealed that body dissatisfaction played a mediating role.A body dissatisfaction score of 1.73 was identified as the diagnostic cutoff value for predicting depression,with an area under the ROC curve of 70.0%,providing a basis for targeted interventions.CONCLUSION This study demonstrated a significant positive correlation between body dissatisfaction and depression.Low levels of physical activity and binge eating behaviors were found to heighten the risk of depression.Therefore,promoting physical activity and healthy eating habits among adolescents is essential.Additionally,the identification of a diagnostic threshold for body dissatisfaction represents a novel finding with important implications for early screening.Future longitudinal studies are recommended to further refine this diagnostic criterion.
基金co-supported by the National Natural Science Foundation of China(No.12372045)the Guangdong Basic and Applied Basic Research Foundation,China(No.2023B1515120018)the Shenzhen Science and Technology Program,China(No.JCYJ20220818102207015).
文摘The increasing complexity of on-orbit tasks imposes great demands on the flexible operation of space robotic arms, prompting the development of space robots from single-arm manipulation to multi-arm collaboration. In this paper, a combined approach of Learning from Demonstration (LfD) and Reinforcement Learning (RL) is proposed for space multi-arm collaborative skill learning. The combination effectively resolves the trade-off between learning efficiency and feasible solution in LfD, as well as the time-consuming pursuit of the optimal solution in RL. With the prior knowledge of LfD, space robotic arms can achieve efficient guided learning in high-dimensional state-action space. Specifically, an LfD approach with Probabilistic Movement Primitives (ProMP) is firstly utilized to encode and reproduce the demonstration actions, generating a distribution as the initialization of policy. Then in the RL stage, a Relative Entropy Policy Search (REPS) algorithm modified in continuous state-action space is employed for further policy improvement. More importantly, the learned behaviors can maintain and reflect the characteristics of demonstrations. In addition, a series of supplementary policy search mechanisms are designed to accelerate the exploration process. The effectiveness of the proposed method has been verified both theoretically and experimentally. Moreover, comparisons with state-of-the-art methods have confirmed the outperformance of the approach.
文摘The Book of Songs is the first collection of poems in China,originally named Poetry,and is one of the Five Classics.Whether in terms of themes,thoughts and emotions,language skills,as well as in artistic images and expression methods,it has shown the great achievements of China’s earliest poetry works and has produced a profound influence on Chinese culture and literature.It not only has recorded the various aspects of the society of that time,but also opens the door to many literary studies.There is no need to argue about its status and significance.In the West,about twelve centuries after the creation of the first poem collected in The Book of Songs,there lived a literary theorist who has performed a great influence on western literature.He was Longinus,the author of On the Sublime.By comparing the aesthetic ideas of Longinus and the artistic characteristics of The Book of Songs,we are surprised to find that The Book of Songs is a paragon of the sublime described by Longinus.
