The motivation for this study is that the quality of deep fakes is constantly improving,which leads to the need to develop new methods for their detection.The proposed Customized Convolutional Neural Network method in...The motivation for this study is that the quality of deep fakes is constantly improving,which leads to the need to develop new methods for their detection.The proposed Customized Convolutional Neural Network method involves extracting structured data from video frames using facial landmark detection,which is then used as input to the CNN.The customized Convolutional Neural Network method is the date augmented-based CNN model to generate‘fake data’or‘fake images’.This study was carried out using Python and its libraries.We used 242 films from the dataset gathered by the Deep Fake Detection Challenge,of which 199 were made up and the remaining 53 were real.Ten seconds were allotted for each video.There were 318 videos used in all,199 of which were fake and 119 of which were real.Our proposedmethod achieved a testing accuracy of 91.47%,loss of 0.342,and AUC score of 0.92,outperforming two alternative approaches,CNN and MLP-CNN.Furthermore,our method succeeded in greater accuracy than contemporary models such as XceptionNet,Meso-4,EfficientNet-BO,MesoInception-4,VGG-16,and DST-Net.The novelty of this investigation is the development of a new Convolutional Neural Network(CNN)learning model that can accurately detect deep fake face photos.展开更多
The development of bioinspired gradient hydrogels with self-sensing actuated capabilities for remote interaction with soft-hard robots remains a challenging endeavor. Here, we propose a novel multifunctional self-sens...The development of bioinspired gradient hydrogels with self-sensing actuated capabilities for remote interaction with soft-hard robots remains a challenging endeavor. Here, we propose a novel multifunctional self-sensing actuated gradient hydrogel that combines ultrafast actuation and high sensitivity for remote interaction with robotic hand. The gradient network structure, achieved through a wettability difference method involving the rapid precipitation of MoO_(2) nanosheets, introduces hydrophilic disparities between two sides within hydrogel. This distinctive approach bestows the hydrogel with ultrafast thermo-responsive actuation(21° s^(-1)) and enhanced photothermal efficiency(increase by 3.7 ℃ s^(-1) under 808 nm near-infrared). Moreover, the local cross-linking of sodium alginate with Ca^(2+) endows the hydrogel with programmable deformability and information display capabilities. Additionally, the hydrogel exhibits high sensitivity(gauge factor 3.94 within a wide strain range of 600%), fast response times(140 ms) and good cycling stability. Leveraging these exceptional properties, we incorporate the hydrogel into various soft actuators, including soft gripper, artificial iris, and bioinspired jellyfish, as well as wearable electronics capable of precise human motion and physiological signal detection. Furthermore, through the synergistic combination of remarkable actuation and sensitivity, we realize a self-sensing touch bioinspired tongue. Notably, by employing quantitative analysis of actuation-sensing, we realize remote interaction between soft-hard robot via the Internet of Things. The multifunctional self-sensing actuated gradient hydrogel presented in this study provides a new insight for advanced somatosensory materials, self-feedback intelligent soft robots and human–machine interactions.展开更多
With the development of digital technology and new models of digital economy,innovation and entrepreneurship education in colleges and universities is facing a new development situation.New methods such as online cour...With the development of digital technology and new models of digital economy,innovation and entrepreneurship education in colleges and universities is facing a new development situation.New methods such as online courses,digital platforms,and value co-creation have brought new opportunities and challenges to the content,mode,and mechanism of innovation and entrepreneurship education.This paper discusses the content and new opportunities of digital entrepreneurship,analyzes the differences between traditional entrepreneurship and digital entrepreneurship,and puts forward the strategy path of entrepreneurship education under the digital economy.展开更多
STEAM(science,technology,engineering,arts,and mathematics)education aims to cultivate innovative talents with multidimensional literacy through interdisciplinary integration and innovative practice.However,lack of stu...STEAM(science,technology,engineering,arts,and mathematics)education aims to cultivate innovative talents with multidimensional literacy through interdisciplinary integration and innovative practice.However,lack of student motivation has emerged as a key factor hindering its effectiveness.This study explores the integrated application of positive emotions and flow experience in STEAM education from the perspective of positive psychology.It systematically explains how these factors enhance learning motivation and promote knowledge internalization,proposing feasible pathways for instructional design,resource provision,environment creation,and team building.The study provides theoretical insights and practical guidance for transforming STEAM education in the new era.展开更多
The support structure of a rotor system is subject to vibration excitation,which results in the stiffness of the support structure varying with the excitation frequency(i.e.,the dynamic stiffness).However,the dynamic ...The support structure of a rotor system is subject to vibration excitation,which results in the stiffness of the support structure varying with the excitation frequency(i.e.,the dynamic stiffness).However,the dynamic stiffness and its effect mechanism have been rarely incorporated in open studies of the rotor system.Therefore,this study theoretically reveals the effect mechanism of dynamic stiffness on the rotor system.Then,the numerical study and experimental verification are conducted on the dynamic stiffness characteristics of a squirrel cage,which is a common support structure for aero-engine.Moreover,the static stiffness experiment is also performed for comparison.Finally,a rotor system model considering the dynamic stiffness of the support structure is presented.The presented rotor model is used to validate the results of the theoretical analysis.The results illustrate that the dynamic stiffness reduces the critical speed of the rotor system and may lead to a new resonance.展开更多
Earth abundant O3-type NaFe_(0.5)Mn_(0.5)O_(2)layered oxide is regarded as one of the most promising cathodes for sodium ion batteries due to its low cost and high energy density.However,its poor structural stability ...Earth abundant O3-type NaFe_(0.5)Mn_(0.5)O_(2)layered oxide is regarded as one of the most promising cathodes for sodium ion batteries due to its low cost and high energy density.However,its poor structural stability and cycle life strongly impede the practical application.Herein,the dynamic phase evolution as well as charge compensation mechanism of O3-type NaFe_(0.5)Mn_(0.5)O_(2)cathode during sodiation/desodiation are revealed by a systemic study with operando X-ray diffraction and X-ray absorption spectroscopy,high resolution neutron powder diffraction and neutron pair distribution functions.The layered structure experiences a phase transition of O3→P3→OP2→ramsdellite during the desodiation,and a new O3’phase is observed at the end of the discharge state(1.5 V).The density functional theory(DFT)calculations and nPDF results suggest that depletion of Na^(+)ions induces the movement of Fe into Na layer resulting the formation of an inert ramsdellite phase thus causing the loss of capacity and structural integrity.Meanwhile,the operando XAS clarified the voltage regions for active Mn^(3+)/Mn^(4+)and Fe^(3+)/Fe^(4+)redox couples.This work points out the universal underneath problem for Fe-based layered oxide cathodes when cycled at high voltage and highlights the importance to suppress Fe migration regarding the design of high energy O3-type cathodes for sodium ion batteries.展开更多
The similitude theory helps to understand the physical behaviors of large structures through scaled models. Several papers have studied the similitude of shock issues. However, the dynamic similitude for shock respons...The similitude theory helps to understand the physical behaviors of large structures through scaled models. Several papers have studied the similitude of shock issues. However, the dynamic similitude for shock responses of coupled structures is rarely incorporated in open studies. In this paper, scaling laws are derived for the shock responses and spectra of coupled structures. In the presented scaling laws, the geometric distortion and energy loss are considered. The ability of the proposed scaling laws is demonstrated in the simulation and experimental cases. In both cases, the similitude prediction for the prototype's time-domain waveform and spectrum is conducted with the scaled model and scaling laws. The simulation and experimental cases indicate that the predicted shock responses and spectra agree well with those of the prototype, which verifies the proposed scaling laws for predicting shock responses.展开更多
1.Introduction The decarbonization of the energy sector,which greatly relies on fossil-fuel energy,requires urgent action on a global scale to reduce carbon emissions to a net-zero state and to mitigate the effects of...1.Introduction The decarbonization of the energy sector,which greatly relies on fossil-fuel energy,requires urgent action on a global scale to reduce carbon emissions to a net-zero state and to mitigate the effects of climate change[1,2].With a multi-level global energy transition already underway,there is an inevitable trend to use renewable energy to replace traditional fossil-fuel energy.展开更多
In this work,the microstructure,hydrogen storage properties,anti-oxide ability and rate limiting step of Zr(Cr_(1−x)Co_(x))_(2)(x=0,0.2,0.4 and 0.6)alloys have been investigated.After studying the crystal structure,we...In this work,the microstructure,hydrogen storage properties,anti-oxide ability and rate limiting step of Zr(Cr_(1−x)Co_(x))_(2)(x=0,0.2,0.4 and 0.6)alloys have been investigated.After studying the crystal structure,we found that all alloy samples could show C14-type phase but the alloy sample x=0 could also show a small amount of Cr phase.Rietveld fitting showed that lattice parameter and unit cell volume of C14-type phase decreased with increasing x.After further research,it was clear that the first hydrogen absorption capacity decreased with increasing x.But introducing more Co content had a positive influence on the effective hydrogen storage capacity and cyclic hydrogen absorption and desorption properties of the alloy sample.We also found that adding Co to ZrCr_(2)alloy could improve its anti-oxide ability.In addition to this,the rate limiting step model was also studied.展开更多
Li metal batteries using high-voltage layered oxides cathodes are of particular interest due to their high energy density.However,they suffer from short lifespan and extreme safety concerns,which are attributed to the...Li metal batteries using high-voltage layered oxides cathodes are of particular interest due to their high energy density.However,they suffer from short lifespan and extreme safety concerns,which are attributed to the degradation of layered oxides and the decomposition of electrolyte at high voltage,as well as the high reactivity of metallic Li.The key is the development of stable electrolytes against both highvoltage cathodes and Li with the formation of robust interphase films on the surfaces.Herein,we report a highly fluorinated ether,1,1,1-trifluoro-2-[(2,2,2-trifluoroethoxy)methoxy]ethane(TTME),as a cosolvent,which not only functions as a diluent forming a localized high concentration electrolyte(LHCE),but also participates in the construction of the inner solvation structure.The TTME-based electrolyte is stable itself at high voltage and induces the formation of a unique double-layer solid electrolyte interphase(SEI)film,which is embodied as one layer rich in crystalline structural components for enhanced mechanical strength and another amorphous layer with a higher concentration of organic components for enhanced flexibility.The Li||Cu cells display a noticeably high Coulombic efficiency of 99.28%after 300 cycles and Li symmetric cells maintain stable cycling more than 3200 h at 0.5 mA/cm^(2) and 1.0m Ah/cm^(2).In addition,lithium metal cells using LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) and Li CoO_(2) cathodes(both loadings~3.0 m Ah/cm^(2))realize capacity retentions of>85%over 240 cycles with a charge cut-off voltage of 4.4 V and 90%for 170 cycles with a charge cut-off voltage of 4.5 V,respectively.This study offers a bifunctional ether-based electrolyte solvent beneficial for high-voltage Li metal batteries.展开更多
Carbon nitrides with two-dimensional layered structures and high theoretical capacities are attractive as anode materials for sodium-ion batteries while their low crystallinity and insufficient structural stability st...Carbon nitrides with two-dimensional layered structures and high theoretical capacities are attractive as anode materials for sodium-ion batteries while their low crystallinity and insufficient structural stability strongly restrict their practical applications.Coupling carbon nitrides with conductive carbon may relieve these issues.However,little is known about the influence of nitrogen(N)configurations on the interactions between carbon and C_(3)N_(4),which is fundamentally critical for guiding the precise design of advanced C_(3)N_(4)-related electrodes.Herein,highly crystalline C_(3)N_(4)(poly(triazine imide),PTI)based all-carbon composites were developed by molten salt strategy.More importantly,the vital role of pyrrolic-N for enhancing charge transfer and boosting Na+storage of C_(3)N_(4)-based composites,which was confirmed by both theoretical and experimental evidence,was spot-highlighted for the first time.By elaborately controlling the salt composition,the composite with high pyrrolic-N and minimized graphitic-N content was obtained.Profiting from the formation of highly crystalline PTI and electrochemically favorable pyrrolic-N configurations,the composite delivered an unusual reverse growth and record-level cycling stability even after 5000 cycles along with high reversible capacity and outstanding full-cell capacity retention.This work broadens the energy storage applications of C_(3)N_(4) and provides new prospects for the design of advanced all-carbon electrodes.展开更多
Maximum power point tracking(MPPT)technology plays a key role in improving the energy conversion efficiency of photovoltaic(PV)systems,especially when multiple local maximum power points(LMPPs)occur under partial shad...Maximum power point tracking(MPPT)technology plays a key role in improving the energy conversion efficiency of photovoltaic(PV)systems,especially when multiple local maximum power points(LMPPs)occur under partial shading conditions(PSC).It is necessary to modify the operating point efficiently and accurately with the help of MPPT technology to maximize the collected power.Even though a lot of research has been carried out and impressive progress achieved for MPPT technology,it still faces some challenges and dilemmas.Firstly,the mathematical model established for PV cells is not precise enough.Second,the existing algorithms are often optimized for specific conditions and lack comprehensive adaptability to the actual operating environment.Besides,a single algorithm may not be able to give full play to its advantages.In the end,the selection criteria for choosing the suitable MPPT algorithm/converter combination to achieve better performance in a given scenario is very limited.Therefore,this paper systematically discusses the current research status and challenges faced by PV MPPT technology around the three aspects of MPPT models,algorithms,and hardware implementation.Through in-depth thinking and discussion,it also puts forward positive perspectives on future development,and five forward-looking solutions to improve the performance of PV systems MPPT are suggested.展开更多
In order to improve the through-thickness homogeneity and properties of aviation aluminum alloy thick plate.The effect of heating-cooling retrogression and re-ageing on the performance of Al-8Zn-2Mg-2Cu alloy thick pl...In order to improve the through-thickness homogeneity and properties of aviation aluminum alloy thick plate.The effect of heating-cooling retrogression and re-ageing on the performance of Al-8Zn-2Mg-2Cu alloy thick plate was investigated by hardness tests, electrical conductivity tests and transmission electron microscopy(TEM) observation.Results revealed that, during retrogression heating, the fine pre-precipitates in surface layer dissolve more and the undissolved η′ or η phases are more coarsened than that of center layer. During slow cooling after retrogression,precipitates continue coarsening but with a lower rate and the secondary precipitation occurs in both layers. Finer precipitates resulting from the secondary precipitation are more in surface. However, the coarsening and secondary precipitation behaviors are restrained in both layers under quick cooling condition. The electrical conductivity and through-thickness homogeneity of precipitates increases while the hardness decreases with cooling rate decreasing. After the optimized non-isothermal retrogression and re-ageing(NRRA) including air-cooling retrogression, the throughthickness homogeneity which is evaluated by integrated retrogression effects has been improved to 94%. The tensile strength, fracture toughness and exfoliation corrosion grade of Al-8Zn-2Mg-2Cu alloy plate is 619 MPa, 24.7 MPa·m^(1/2)and EB, respectively, which indicates that the non-isothermal retrogression and re-aging(NRRA) could improve the mechanical properties and corrosion resistance with higher through-thickness homogeneity.展开更多
An inexpensive coordinated ionic liquid NMP-0.5ZnCl_(2) was synthesized by reacting N-methyl-pyrrolidone with anhydrous ZnCl_(2),and its structure was characterized with FT-IR spectroscopy.The performance of IL for re...An inexpensive coordinated ionic liquid NMP-0.5ZnCl_(2) was synthesized by reacting N-methyl-pyrrolidone with anhydrous ZnCl_(2),and its structure was characterized with FT-IR spectroscopy.The performance of IL for removing basic nitrogen compounds from model oil containing quinoline and actual coker diesel was studied.Experimental results showed that the IL,NMP-0.5ZnCl_(2),exhibited a good denitrogenation performance,which can be attributed to its low viscosity and unoccupied orbitals of Zn ion,while obtaining a 99.68%quinoline removal efficiency under conditions covering a temperature of 50℃,an IL/model oil mass ratio of 1:2,and a reaction time of 30 min.In the case of coker diesel,above a 91%basic N-removal efficiency(with N-content reduced from 536μg/g to 47μg/g)was realized by the IL after 5-stage extraction.Moreover,the quinoline extraction efficiency could still reach 96.73%during four recycles of the IL.展开更多
Deep eutectic solvents(DESs)1-butyl-3-methylimidazolium bromide-polyalcohol([Bmim]Br-polyalcohol)were synthesized from[Bmim]Br and polyalcohol such as ethylene glycol(EG),propylene glycol(PG),glycerol(GL)at a molar ra...Deep eutectic solvents(DESs)1-butyl-3-methylimidazolium bromide-polyalcohol([Bmim]Br-polyalcohol)were synthesized from[Bmim]Br and polyalcohol such as ethylene glycol(EG),propylene glycol(PG),glycerol(GL)at a molar ratio of 1:2.[Bmim]Br-2propylene glycol([Bmim]Br-2PG)was characterized with FT-IR spectroscopy and 1H NMR.The removal of benzothiophene(BT)from model oil was investigated by extraction with DES[Bmim]Br-2PG.The results showed that an extraction efficiency as high as 54.1%could be achieved with the solvent in one-stage extraction at 30℃in 30 min with a DES/oil mass ratio of 1:1.Deep desulfurization was realized after five-stage extraction,and sulfur content in model oil was reduced to less than 10μg/g.The used[Bmim]Br-2PG DES was regenerated and showed an extraction efficiency of 50.5%within four recycles.展开更多
Comelina sotivo is an oil seed crop which can be grown on marginal lands. Camelina seed oil is rich in omega-3 fatty acids (〉35%) and y-tocopherol but is also high in erucic acid and glucosinolates. Camelina meal, ...Comelina sotivo is an oil seed crop which can be grown on marginal lands. Camelina seed oil is rich in omega-3 fatty acids (〉35%) and y-tocopherol but is also high in erucic acid and glucosinolates. Camelina meal, is the by-product after the oil has been extracted. Camelina meal was fed to 28 d old weaned pigs at 3.7% and 7.4% unt age 56 d. The camelina meal supplements in the soy based diets, improved feed efficiency but also significantly increased the liver weights. Gene expression analyses of the livers, using intra-species microarrays, identified increased expression of phase 1 and phase 2 drug metabolism enzymes. The porcine versions of the enzymes were confirmed by real time PCR. Cytochrome 8b1 (CYPSB1), aldehyde dehydrogenase 2 (Aldh2), and thiosulfate transferase (TST) were all significantly stimulated. Collectively, these genes implicate the camelina glucosinolate metabolite, methyl-sulfinyldecyl isothiocyanate, as the main xeniobiotic, causing increased hepatic metabolism and increased liver weight.展开更多
The stress corrosion of S355 steel in 3.5% NaCl solution under the different strain rates was analyzed with the slow strain rate test(SSRT), the stress corrosion cracking(SCC) behaviors of S355 steel under the dif...The stress corrosion of S355 steel in 3.5% NaCl solution under the different strain rates was analyzed with the slow strain rate test(SSRT), the stress corrosion cracking(SCC) behaviors of S355 steel under the different strain rates in the solution were investigated, and the fracture morphologies and compositions of corrosion products under the different strain rates were analyzed with scanning electron microscopy(SEM) and energy dispersive spectrometerry(EDS), respectively. The experimental results show that the SCC sensitivity index is the highest when the strain rate is 2×10-6, and the medium corrosion is the main reason resulting in the highest SCC sensitivity index. The SCC sensitivity index is the least when the strain rate is 5×10-6, and the stress is the main reason resulting in the stress corrosion. The SCC sensitivity index is the middle when the strain rate is 9×10-6, the interaction of stress and medium is the stress corrosion fracture mechanism.展开更多
In the global competition for talents,the massive inflow of Chinese students into the UK has drawn great attention.However,only a few studies examine students’interactions with socioeconomic structures in their study...In the global competition for talents,the massive inflow of Chinese students into the UK has drawn great attention.However,only a few studies examine students’interactions with socioeconomic structures in their study-to-work transition.This study used Higher Education Statistics AgencyHESA,22data and interview data collected from Chinese postgraduate students,and it aims to:investigate structural factors that influence post-study migration patterns of Chinese students;and explore how Chinese students interact with wider social structures.This study found that different configurations between students"goals,""actions,"and"reflexivity"would lead to different employment outcomes.Three different study-to-work transition strategies were identified:"proceeding without a fixed plan";"reaching a compromise";and"knowing goals and approaching goals".Findings suggest that the transition between study and work is more complex than what is described in human capital and push-pull approaches.A better understanding of students’decision-making processes would help higher education institutions in preparing graduates for careers in the global labour market.展开更多
Financial quotient education has become an inevitable requirement of quality education in China,with vital practical significance.By investigating the current financial education situation for teenagers in Banan Distr...Financial quotient education has become an inevitable requirement of quality education in China,with vital practical significance.By investigating the current financial education situation for teenagers in Banan District,Chongqing,we find some problems such as parents'weak awareness of financial education,lack of financial education in schools,and lack of professional teachers.This paper proposes the"three-in-one"financial quotient education implementation path of family,school,and government,hoping to explore the construction of a youth financial quotient education system and provide a reference for various subjects to carry out financial quotient education for young people.Further,enrich the achievements of characteristic education and promote the development of quality education in primary and secondary schools.展开更多
Deepening the integration of industryand educationand school-enterprise cooperation are effective waysto cultivate high-quality applied talents.It has become an essentialdemand for social and economic development and ...Deepening the integration of industryand educationand school-enterprise cooperation are effective waysto cultivate high-quality applied talents.It has become an essentialdemand for social and economic development and an inevitable trend for applied undergraduatescolleges.In view of this,based on the development strategy of national and local integration of industry and education and the demand for talents in the human resources industry,this article takes human resource management as an example,combined with the current situation of industry and education integration of applied undergraduate human resource management,and explores its products from the perspective of one course and two teachers.It also proposes a guarantee mechanism for integratingindustryand education from the aspects of top-level guarantee,multiple evaluations,teaching co-management,and teacher incentives.It is hoped to establishan application-oriented undergraduate human resource management professional industryand education implementation systemand promote the deep integration of applied undergraduate industry and education.展开更多
基金Science and Technology Funds from the Liaoning Education Department(Serial Number:LJKZ0104).
文摘The motivation for this study is that the quality of deep fakes is constantly improving,which leads to the need to develop new methods for their detection.The proposed Customized Convolutional Neural Network method involves extracting structured data from video frames using facial landmark detection,which is then used as input to the CNN.The customized Convolutional Neural Network method is the date augmented-based CNN model to generate‘fake data’or‘fake images’.This study was carried out using Python and its libraries.We used 242 films from the dataset gathered by the Deep Fake Detection Challenge,of which 199 were made up and the remaining 53 were real.Ten seconds were allotted for each video.There were 318 videos used in all,199 of which were fake and 119 of which were real.Our proposedmethod achieved a testing accuracy of 91.47%,loss of 0.342,and AUC score of 0.92,outperforming two alternative approaches,CNN and MLP-CNN.Furthermore,our method succeeded in greater accuracy than contemporary models such as XceptionNet,Meso-4,EfficientNet-BO,MesoInception-4,VGG-16,and DST-Net.The novelty of this investigation is the development of a new Convolutional Neural Network(CNN)learning model that can accurately detect deep fake face photos.
基金The financial support from the National Natural Science Foundation of China (32201179)Guangdong Basic and Applied Basic Research Foundation (2020A1515110126 and 2021A1515010130)+1 种基金the Fundamental Research Funds for the Central Universities (N2319005)Ningbo Science and Technology Major Project (2021Z027) is gratefully acknowledged。
文摘The development of bioinspired gradient hydrogels with self-sensing actuated capabilities for remote interaction with soft-hard robots remains a challenging endeavor. Here, we propose a novel multifunctional self-sensing actuated gradient hydrogel that combines ultrafast actuation and high sensitivity for remote interaction with robotic hand. The gradient network structure, achieved through a wettability difference method involving the rapid precipitation of MoO_(2) nanosheets, introduces hydrophilic disparities between two sides within hydrogel. This distinctive approach bestows the hydrogel with ultrafast thermo-responsive actuation(21° s^(-1)) and enhanced photothermal efficiency(increase by 3.7 ℃ s^(-1) under 808 nm near-infrared). Moreover, the local cross-linking of sodium alginate with Ca^(2+) endows the hydrogel with programmable deformability and information display capabilities. Additionally, the hydrogel exhibits high sensitivity(gauge factor 3.94 within a wide strain range of 600%), fast response times(140 ms) and good cycling stability. Leveraging these exceptional properties, we incorporate the hydrogel into various soft actuators, including soft gripper, artificial iris, and bioinspired jellyfish, as well as wearable electronics capable of precise human motion and physiological signal detection. Furthermore, through the synergistic combination of remarkable actuation and sensitivity, we realize a self-sensing touch bioinspired tongue. Notably, by employing quantitative analysis of actuation-sensing, we realize remote interaction between soft-hard robot via the Internet of Things. The multifunctional self-sensing actuated gradient hydrogel presented in this study provides a new insight for advanced somatosensory materials, self-feedback intelligent soft robots and human–machine interactions.
基金supported by project fund support Key Project of Philosophy and Social Sciences of Anhui Province,China(2022AH051929)Analysis on the Construction of College Students’Innovation and Entrepreneurship Education System under the Digital Economy Environment(2021jyxm1404)+1 种基金Innovation and Entrepreneurship Training Program for College Students(Inspiration from the Development of Huizhou Salt Merchants in Ming and Qing Dynasties to the Production and Management of Modern Enterprises,2210375144)Exploration of Collaborative Education Path between Labor Education and Innovation and Entrepreneurship Education in Colleges and Universities in the New Era(2021jyxm1392).
文摘With the development of digital technology and new models of digital economy,innovation and entrepreneurship education in colleges and universities is facing a new development situation.New methods such as online courses,digital platforms,and value co-creation have brought new opportunities and challenges to the content,mode,and mechanism of innovation and entrepreneurship education.This paper discusses the content and new opportunities of digital entrepreneurship,analyzes the differences between traditional entrepreneurship and digital entrepreneurship,and puts forward the strategy path of entrepreneurship education under the digital economy.
基金Key Scientific Research Project of Henan Provincial Colleges and Universities“Construction of an Innovation and Entrepreneurship Education Ecosystem Model in Colleges and Universities Based on Ecological Theory”(24B880048)Research and Practice Project on Education and Teaching Reform in Henan Provincial Colleges and Universities(Employment and Innovation and Entrepreneurship Education)“Construction and Practice of a‘3+N’Practical Education System Based on Employment and Education Orientation”(2024SJGLX1083)+1 种基金Research and Practice Project on Teaching Reform in Higher Education in Henan Province“Practical Exploration of the‘3+3+X’Collaborative Education Model for Mental Health Education in Medical Schools”(2024SJGLX0142)Research and Practice Project on Education and Teaching Reform at Xinxiang Medical University“Practical Exploration of Conflicts and Countermeasures in Medical Students’Internships,Postgraduate Entrance Exams,and Employment from the Perspective of the Conflict Between Work and Study”(2021-XYJG-98)。
文摘STEAM(science,technology,engineering,arts,and mathematics)education aims to cultivate innovative talents with multidimensional literacy through interdisciplinary integration and innovative practice.However,lack of student motivation has emerged as a key factor hindering its effectiveness.This study explores the integrated application of positive emotions and flow experience in STEAM education from the perspective of positive psychology.It systematically explains how these factors enhance learning motivation and promote knowledge internalization,proposing feasible pathways for instructional design,resource provision,environment creation,and team building.The study provides theoretical insights and practical guidance for transforming STEAM education in the new era.
基金the National Natural Science Foundation of China(Nos.11872148 and U1908217)the Fundamental Research Funds for the Central Universities of China(Nos.N2224001-4 and N2003013)the Basic and Applied Basic Research Foundation of Guangdong Province of China(No.2020B1515120015)。
文摘The support structure of a rotor system is subject to vibration excitation,which results in the stiffness of the support structure varying with the excitation frequency(i.e.,the dynamic stiffness).However,the dynamic stiffness and its effect mechanism have been rarely incorporated in open studies of the rotor system.Therefore,this study theoretically reveals the effect mechanism of dynamic stiffness on the rotor system.Then,the numerical study and experimental verification are conducted on the dynamic stiffness characteristics of a squirrel cage,which is a common support structure for aero-engine.Moreover,the static stiffness experiment is also performed for comparison.Finally,a rotor system model considering the dynamic stiffness of the support structure is presented.The presented rotor model is used to validate the results of the theoretical analysis.The results illustrate that the dynamic stiffness reduces the critical speed of the rotor system and may lead to a new resonance.
基金financial support of the Guangdong Basic and Applied Basic Research Foundation(2019A1515110897 and 2019B1515120028)。
文摘Earth abundant O3-type NaFe_(0.5)Mn_(0.5)O_(2)layered oxide is regarded as one of the most promising cathodes for sodium ion batteries due to its low cost and high energy density.However,its poor structural stability and cycle life strongly impede the practical application.Herein,the dynamic phase evolution as well as charge compensation mechanism of O3-type NaFe_(0.5)Mn_(0.5)O_(2)cathode during sodiation/desodiation are revealed by a systemic study with operando X-ray diffraction and X-ray absorption spectroscopy,high resolution neutron powder diffraction and neutron pair distribution functions.The layered structure experiences a phase transition of O3→P3→OP2→ramsdellite during the desodiation,and a new O3’phase is observed at the end of the discharge state(1.5 V).The density functional theory(DFT)calculations and nPDF results suggest that depletion of Na^(+)ions induces the movement of Fe into Na layer resulting the formation of an inert ramsdellite phase thus causing the loss of capacity and structural integrity.Meanwhile,the operando XAS clarified the voltage regions for active Mn^(3+)/Mn^(4+)and Fe^(3+)/Fe^(4+)redox couples.This work points out the universal underneath problem for Fe-based layered oxide cathodes when cycled at high voltage and highlights the importance to suppress Fe migration regarding the design of high energy O3-type cathodes for sodium ion batteries.
基金Project supported by the National Natural Science Foundation of China (Nos. 12272089 and U1908217)the Fundamental Research Funds for the Central Universities of China (Nos. N2224001-4 and N2003013)the Basic and Applied Basic Research Foundation of Guangdong Province of China (No. 2020B1515120015)。
文摘The similitude theory helps to understand the physical behaviors of large structures through scaled models. Several papers have studied the similitude of shock issues. However, the dynamic similitude for shock responses of coupled structures is rarely incorporated in open studies. In this paper, scaling laws are derived for the shock responses and spectra of coupled structures. In the presented scaling laws, the geometric distortion and energy loss are considered. The ability of the proposed scaling laws is demonstrated in the simulation and experimental cases. In both cases, the similitude prediction for the prototype's time-domain waveform and spectrum is conducted with the scaled model and scaling laws. The simulation and experimental cases indicate that the predicted shock responses and spectra agree well with those of the prototype, which verifies the proposed scaling laws for predicting shock responses.
文摘1.Introduction The decarbonization of the energy sector,which greatly relies on fossil-fuel energy,requires urgent action on a global scale to reduce carbon emissions to a net-zero state and to mitigate the effects of climate change[1,2].With a multi-level global energy transition already underway,there is an inevitable trend to use renewable energy to replace traditional fossil-fuel energy.
基金supported by Natural Science Foundation of Jiangxi Province(20202BABL214003)Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation(JXMS202008 and JXMS202009)+4 种基金Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices(PMND201902)Engineering Research Center of Nuclear Technology Application(East China University of Technology)Ministry of Education(HJSJYB2019–5)Science and Technology Project Founded by Education Department of Jiangxi Province(GJJ190406)Research Foundation for Advanced Talents of East China University of Technology(DHBK2019091).
文摘In this work,the microstructure,hydrogen storage properties,anti-oxide ability and rate limiting step of Zr(Cr_(1−x)Co_(x))_(2)(x=0,0.2,0.4 and 0.6)alloys have been investigated.After studying the crystal structure,we found that all alloy samples could show C14-type phase but the alloy sample x=0 could also show a small amount of Cr phase.Rietveld fitting showed that lattice parameter and unit cell volume of C14-type phase decreased with increasing x.After further research,it was clear that the first hydrogen absorption capacity decreased with increasing x.But introducing more Co content had a positive influence on the effective hydrogen storage capacity and cyclic hydrogen absorption and desorption properties of the alloy sample.We also found that adding Co to ZrCr_(2)alloy could improve its anti-oxide ability.In addition to this,the rate limiting step model was also studied.
基金the financial supports from the KeyArea Research and Development Program of Guangdong Province (2020B090919001)the National Natural Science Foundation of China (22078144)the Guangdong Natural Science Foundation for Basic and Applied Basic Research (2021A1515010138 and 2023A1515010686)。
文摘Li metal batteries using high-voltage layered oxides cathodes are of particular interest due to their high energy density.However,they suffer from short lifespan and extreme safety concerns,which are attributed to the degradation of layered oxides and the decomposition of electrolyte at high voltage,as well as the high reactivity of metallic Li.The key is the development of stable electrolytes against both highvoltage cathodes and Li with the formation of robust interphase films on the surfaces.Herein,we report a highly fluorinated ether,1,1,1-trifluoro-2-[(2,2,2-trifluoroethoxy)methoxy]ethane(TTME),as a cosolvent,which not only functions as a diluent forming a localized high concentration electrolyte(LHCE),but also participates in the construction of the inner solvation structure.The TTME-based electrolyte is stable itself at high voltage and induces the formation of a unique double-layer solid electrolyte interphase(SEI)film,which is embodied as one layer rich in crystalline structural components for enhanced mechanical strength and another amorphous layer with a higher concentration of organic components for enhanced flexibility.The Li||Cu cells display a noticeably high Coulombic efficiency of 99.28%after 300 cycles and Li symmetric cells maintain stable cycling more than 3200 h at 0.5 mA/cm^(2) and 1.0m Ah/cm^(2).In addition,lithium metal cells using LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) and Li CoO_(2) cathodes(both loadings~3.0 m Ah/cm^(2))realize capacity retentions of>85%over 240 cycles with a charge cut-off voltage of 4.4 V and 90%for 170 cycles with a charge cut-off voltage of 4.5 V,respectively.This study offers a bifunctional ether-based electrolyte solvent beneficial for high-voltage Li metal batteries.
基金supported by the National Natural Science Foundation of China(51904059)Applied Basic Research Program of Liaoning(2022JH2/101300200)+1 种基金Guangdong Basic and Applied Basic Research Foundation(2022A1515140188)Fundamental Research Funds for the Central Universities(N_(2)002005,N_(2)125004,N_(2)225044)。
文摘Carbon nitrides with two-dimensional layered structures and high theoretical capacities are attractive as anode materials for sodium-ion batteries while their low crystallinity and insufficient structural stability strongly restrict their practical applications.Coupling carbon nitrides with conductive carbon may relieve these issues.However,little is known about the influence of nitrogen(N)configurations on the interactions between carbon and C_(3)N_(4),which is fundamentally critical for guiding the precise design of advanced C_(3)N_(4)-related electrodes.Herein,highly crystalline C_(3)N_(4)(poly(triazine imide),PTI)based all-carbon composites were developed by molten salt strategy.More importantly,the vital role of pyrrolic-N for enhancing charge transfer and boosting Na+storage of C_(3)N_(4)-based composites,which was confirmed by both theoretical and experimental evidence,was spot-highlighted for the first time.By elaborately controlling the salt composition,the composite with high pyrrolic-N and minimized graphitic-N content was obtained.Profiting from the formation of highly crystalline PTI and electrochemically favorable pyrrolic-N configurations,the composite delivered an unusual reverse growth and record-level cycling stability even after 5000 cycles along with high reversible capacity and outstanding full-cell capacity retention.This work broadens the energy storage applications of C_(3)N_(4) and provides new prospects for the design of advanced all-carbon electrodes.
基金funding from the Open Fund Project of Intelligent Electric Power Grid Key Laboratory of Sichuan Province under Grant(2023-IEPGKLSP-KFYB03)Yunnan Provincial Basic Research Project(202301AT070443).
文摘Maximum power point tracking(MPPT)technology plays a key role in improving the energy conversion efficiency of photovoltaic(PV)systems,especially when multiple local maximum power points(LMPPs)occur under partial shading conditions(PSC).It is necessary to modify the operating point efficiently and accurately with the help of MPPT technology to maximize the collected power.Even though a lot of research has been carried out and impressive progress achieved for MPPT technology,it still faces some challenges and dilemmas.Firstly,the mathematical model established for PV cells is not precise enough.Second,the existing algorithms are often optimized for specific conditions and lack comprehensive adaptability to the actual operating environment.Besides,a single algorithm may not be able to give full play to its advantages.In the end,the selection criteria for choosing the suitable MPPT algorithm/converter combination to achieve better performance in a given scenario is very limited.Therefore,this paper systematically discusses the current research status and challenges faced by PV MPPT technology around the three aspects of MPPT models,algorithms,and hardware implementation.Through in-depth thinking and discussion,it also puts forward positive perspectives on future development,and five forward-looking solutions to improve the performance of PV systems MPPT are suggested.
基金Project(51801082) supported by National Natural Science Foundation of ChinaProjects(GY2021003, GY2021020)supported by the Key Research and Development Program of Zhenjiang City,China+1 种基金Project(KYCX21_3453) supported by Graduate Research and Innovation Projects in Jiangsu Province,ChinaProject(202110289002Z) supported by Undergraduate Innovation and Entrepreneurship Training Program of Jiangsu Province,China。
文摘In order to improve the through-thickness homogeneity and properties of aviation aluminum alloy thick plate.The effect of heating-cooling retrogression and re-ageing on the performance of Al-8Zn-2Mg-2Cu alloy thick plate was investigated by hardness tests, electrical conductivity tests and transmission electron microscopy(TEM) observation.Results revealed that, during retrogression heating, the fine pre-precipitates in surface layer dissolve more and the undissolved η′ or η phases are more coarsened than that of center layer. During slow cooling after retrogression,precipitates continue coarsening but with a lower rate and the secondary precipitation occurs in both layers. Finer precipitates resulting from the secondary precipitation are more in surface. However, the coarsening and secondary precipitation behaviors are restrained in both layers under quick cooling condition. The electrical conductivity and through-thickness homogeneity of precipitates increases while the hardness decreases with cooling rate decreasing. After the optimized non-isothermal retrogression and re-ageing(NRRA) including air-cooling retrogression, the throughthickness homogeneity which is evaluated by integrated retrogression effects has been improved to 94%. The tensile strength, fracture toughness and exfoliation corrosion grade of Al-8Zn-2Mg-2Cu alloy plate is 619 MPa, 24.7 MPa·m^(1/2)and EB, respectively, which indicates that the non-isothermal retrogression and re-aging(NRRA) could improve the mechanical properties and corrosion resistance with higher through-thickness homogeneity.
基金The authors are grateful for financial support from the Doctoral Funds of Liaoning Provincial Natural Science Foundation(201601323)the Research Startup Foundation of Liaoning Petrochemical University(2019xJJ-006).
文摘An inexpensive coordinated ionic liquid NMP-0.5ZnCl_(2) was synthesized by reacting N-methyl-pyrrolidone with anhydrous ZnCl_(2),and its structure was characterized with FT-IR spectroscopy.The performance of IL for removing basic nitrogen compounds from model oil containing quinoline and actual coker diesel was studied.Experimental results showed that the IL,NMP-0.5ZnCl_(2),exhibited a good denitrogenation performance,which can be attributed to its low viscosity and unoccupied orbitals of Zn ion,while obtaining a 99.68%quinoline removal efficiency under conditions covering a temperature of 50℃,an IL/model oil mass ratio of 1:2,and a reaction time of 30 min.In the case of coker diesel,above a 91%basic N-removal efficiency(with N-content reduced from 536μg/g to 47μg/g)was realized by the IL after 5-stage extraction.Moreover,the quinoline extraction efficiency could still reach 96.73%during four recycles of the IL.
基金The authors are grateful for financial support from the Doctoral Scientific Research Foundation of Liaoning Shihua University(2019×JJ-006).
文摘Deep eutectic solvents(DESs)1-butyl-3-methylimidazolium bromide-polyalcohol([Bmim]Br-polyalcohol)were synthesized from[Bmim]Br and polyalcohol such as ethylene glycol(EG),propylene glycol(PG),glycerol(GL)at a molar ratio of 1:2.[Bmim]Br-2propylene glycol([Bmim]Br-2PG)was characterized with FT-IR spectroscopy and 1H NMR.The removal of benzothiophene(BT)from model oil was investigated by extraction with DES[Bmim]Br-2PG.The results showed that an extraction efficiency as high as 54.1%could be achieved with the solvent in one-stage extraction at 30℃in 30 min with a DES/oil mass ratio of 1:1.Deep desulfurization was realized after five-stage extraction,and sulfur content in model oil was reduced to less than 10μg/g.The used[Bmim]Br-2PG DES was regenerated and showed an extraction efficiency of 50.5%within four recycles.
文摘Comelina sotivo is an oil seed crop which can be grown on marginal lands. Camelina seed oil is rich in omega-3 fatty acids (〉35%) and y-tocopherol but is also high in erucic acid and glucosinolates. Camelina meal, is the by-product after the oil has been extracted. Camelina meal was fed to 28 d old weaned pigs at 3.7% and 7.4% unt age 56 d. The camelina meal supplements in the soy based diets, improved feed efficiency but also significantly increased the liver weights. Gene expression analyses of the livers, using intra-species microarrays, identified increased expression of phase 1 and phase 2 drug metabolism enzymes. The porcine versions of the enzymes were confirmed by real time PCR. Cytochrome 8b1 (CYPSB1), aldehyde dehydrogenase 2 (Aldh2), and thiosulfate transferase (TST) were all significantly stimulated. Collectively, these genes implicate the camelina glucosinolate metabolite, methyl-sulfinyldecyl isothiocyanate, as the main xeniobiotic, causing increased hepatic metabolism and increased liver weight.
基金Funded by the Key Research and Development Project of Jiangsu Province(BE2016052)
文摘The stress corrosion of S355 steel in 3.5% NaCl solution under the different strain rates was analyzed with the slow strain rate test(SSRT), the stress corrosion cracking(SCC) behaviors of S355 steel under the different strain rates in the solution were investigated, and the fracture morphologies and compositions of corrosion products under the different strain rates were analyzed with scanning electron microscopy(SEM) and energy dispersive spectrometerry(EDS), respectively. The experimental results show that the SCC sensitivity index is the highest when the strain rate is 2×10-6, and the medium corrosion is the main reason resulting in the highest SCC sensitivity index. The SCC sensitivity index is the least when the strain rate is 5×10-6, and the stress is the main reason resulting in the stress corrosion. The SCC sensitivity index is the middle when the strain rate is 9×10-6, the interaction of stress and medium is the stress corrosion fracture mechanism.
基金This research is supported by the Wenzhou Social Science Fund(Grant No.21JD10).
文摘In the global competition for talents,the massive inflow of Chinese students into the UK has drawn great attention.However,only a few studies examine students’interactions with socioeconomic structures in their study-to-work transition.This study used Higher Education Statistics AgencyHESA,22data and interview data collected from Chinese postgraduate students,and it aims to:investigate structural factors that influence post-study migration patterns of Chinese students;and explore how Chinese students interact with wider social structures.This study found that different configurations between students"goals,""actions,"and"reflexivity"would lead to different employment outcomes.Three different study-to-work transition strategies were identified:"proceeding without a fixed plan";"reaching a compromise";and"knowing goals and approaching goals".Findings suggest that the transition between study and work is more complex than what is described in human capital and push-pull approaches.A better understanding of students’decision-making processes would help higher education institutions in preparing graduates for careers in the global labour market.
文摘Financial quotient education has become an inevitable requirement of quality education in China,with vital practical significance.By investigating the current financial education situation for teenagers in Banan District,Chongqing,we find some problems such as parents'weak awareness of financial education,lack of financial education in schools,and lack of professional teachers.This paper proposes the"three-in-one"financial quotient education implementation path of family,school,and government,hoping to explore the construction of a youth financial quotient education system and provide a reference for various subjects to carry out financial quotient education for young people.Further,enrich the achievements of characteristic education and promote the development of quality education in primary and secondary schools.
基金This work is supported by the Chongqing Higher Education Teaching Reform Research Key Project(202128)Chongqing Institute of Technology Education and Teaching Reform Research Project(JY2019205).
文摘Deepening the integration of industryand educationand school-enterprise cooperation are effective waysto cultivate high-quality applied talents.It has become an essentialdemand for social and economic development and an inevitable trend for applied undergraduatescolleges.In view of this,based on the development strategy of national and local integration of industry and education and the demand for talents in the human resources industry,this article takes human resource management as an example,combined with the current situation of industry and education integration of applied undergraduate human resource management,and explores its products from the perspective of one course and two teachers.It also proposes a guarantee mechanism for integratingindustryand education from the aspects of top-level guarantee,multiple evaluations,teaching co-management,and teacher incentives.It is hoped to establishan application-oriented undergraduate human resource management professional industryand education implementation systemand promote the deep integration of applied undergraduate industry and education.