Research purpose:This study implemented somatosensory music therapy on patients with depressive disorders,and explored the effects of somatosensory music therapy on the degree of depression,positive and negative emoti...Research purpose:This study implemented somatosensory music therapy on patients with depressive disorders,and explored the effects of somatosensory music therapy on the degree of depression,positive and negative emotions,intuitive stress and autonomic nervous function of patients.Research method:We collected 66 patients diagnosed with depression from the Department of Psychological Medicine of Henan Provincial People’s Hospital,and divided them into a control group and an intervention group according to the random number table,with 33 people in each group.The control group received routine psychiatric treatment and nursing.On the basis of the control group,the intervention group received somatosensory music therapy 3 times a week,30 min each time,for 4 consecutive weeks.The Hamilton Depression Scale,Positive and Negative Emotion Scale,Perceived Stress Scale,and Heart Rate Variability Index were collected and analyzed at baseline(T0),2 weeks after treatment(T1)and 4 weeks after treatment(T2).Research results:After 4 weeks of treatment,the HAMD scores of the two groups decreased to varying degrees,and the difference between the groups was statistically significant(p<0.05).After 4 weeks of treatment,the scores of positive emotions in both groups increased to varying degrees,and the scores of negative emotions increased to varying degrees.The scores decreased to varying degrees,and there were statistically significant differences between the positive and negative emotion groups(p<0.05).After 4 weeks of treatment,the CPSS scores of the two groups decreased to varying degrees,and the difference between the two groups was statistically significant(p<0.05).Analyzing the main effect of intervention factors alone,after 4 weeks of treatment,SDNN and RMSSD indexes all increased to varying degrees,and the degree of increase in the intervention group was greater than that in the control group,and the difference between the groups was statistically significant(p<0.05).Research conclusion:assisting somatosensory music therapy for patients with depressive disorders can improve depressive symptoms,increase positive emotions,reduce negative emotions,and reduce perceived stress.These are beneficial to restore the balance of autonomic nervous system,and are effective for the treatment of depression.展开更多
Starting from the purpose and current situation of the implementation of action of "Xuchang being full of green",this study analyzed the problems existing in the implementation of action of "Xuchang bei...Starting from the purpose and current situation of the implementation of action of "Xuchang being full of green",this study analyzed the problems existing in the implementation of action of "Xuchang being full of green" and discussed the implementation plan of action of "Xuchang being full of green" from two aspects of macro strategy and node promotion strategy,hoping to promote the construction of ecological garden cities in Xuchang and other cities in China.展开更多
Urban functional area(UFA)is a core scientific issue affecting urban sustainability.The current knowledge gap is mainly reflected in the lack of multi-scale quantitative interpretation methods from the perspective of ...Urban functional area(UFA)is a core scientific issue affecting urban sustainability.The current knowledge gap is mainly reflected in the lack of multi-scale quantitative interpretation methods from the perspective of human-land interaction.In this paper,based on multi-source big data include 250 m×250 m resolution cell phone data,1.81×105 Points of Interest(POI)data and administrative boundary data,we built a UFA identification method and demonstrated empirically in Shenyang City,China.We argue that the method we built can effectively identify multi-scale multi-type UFAs based on human activity and further reveal the spatial correlation between urban facilities and human activity.The empirical study suggests that the employment functional zones in Shenyang City are more concentrated in central cities than other single functional zones.There are more mix functional areas in the central city areas,while the planned industrial new cities need to develop comprehensive functions in Shenyang.UFAs have scale effects and human-land interaction patterns.We suggest that city decision makers should apply multi-sources big data to measure urban functional service in a more refined manner from a supply-demand perspective.展开更多
Non-Hermitian dissipation dynamics,capable of turning the conventionally detrimental decoherence effects to useful resources for state engineering,is highly attractive to quantum information processing.In this work,an...Non-Hermitian dissipation dynamics,capable of turning the conventionally detrimental decoherence effects to useful resources for state engineering,is highly attractive to quantum information processing.In this work,an effective scheme is developed for implementing fast population transfer with a superconducting qutrit via the non-Hermitian shortcut to adiabaticity(STA).We first deal with aΛ-configuration interaction between the qutrit and microwave drivings,in which the dephasing-assisted qubit state inversion requiring an overlarge dephasing rate is constructed non-adiabatically.After introducing a feasible ancillary driving that directly acts upon the qubit states,the target state transfer can be well realized but with an accessible qubit dephasing rate.Moreover,a high fidelity could be numerically obtained in the considered system.The strategy could provide a new route towards the non-Hermitian shortcut operations on superconducting quantum circuits.展开更多
Exploring materials with high electrochemical activity is of keen interest for electrochemistry-controlled optical and energy storage devices.However,it remains a great challenge for transition metal oxides to meet th...Exploring materials with high electrochemical activity is of keen interest for electrochemistry-controlled optical and energy storage devices.However,it remains a great challenge for transition metal oxides to meet this feature due to their low electron conductivity and insufficient reaction sites.Here,we propose a type of transition metal phosphate(NiHPO_(4)·3H_(2)O,NHP)by a facile and scalable electrodeposition method,which can achieve the capability of efficient ion accommodation and injection/extraction for electrochromic energy storage applications.Specifically,the NHP film with an ultra-high transmittance(approach to 100%)achieves a large optical modulation(90.8%at 500 nm),high coloration efficiency(75.4 cm^(2)C^(-1)at 500 nm),and a high specific capacity of 47.8 mAh g^(-1)at 0.4 A g^(-1).Furthermore,the transformation mechanism of NHP upon electrochemical reaction is systematically elucidated using in situ and ex situ techniques.Ultimately,a large-area electrochromic smart window with 100 cm^(2)is constructed based on the NHP electrode,displaying superior electrochromic energy storage performance in regulating natural light and storing electrical charges.Our findings may open up new strategies for developing advanced electrochromic energy storage materials and smart windows.展开更多
With rapid developments in the field of very large-scale integrated circuits,heat dissipation has emerged as a significant factor that restricts the high-density integration of chips.Due to their high thermal conducti...With rapid developments in the field of very large-scale integrated circuits,heat dissipation has emerged as a significant factor that restricts the high-density integration of chips.Due to their high thermal conductivity and low thermal expansion coefficient,diamond/Cu composites have attracted considerable attention as a promising thermal management material.In this study,a surface tungsten carbide gradient layer coating of diamond particles has been realized using comprehensive magnetron sputtering technology and a heat treatment process.Diamond/Cu composites were prepared using high-temperature and high-pressure technology.The results show that,by adjusting the heat treatment process,tungsten carbide and di-tungsten carbide are generated by an in situ reaction at the tungsten–diamond interface,and W–WC–W_(2)C gradient layer-coated diamond particles were obtained.The diamond/Cu composites were sintered by high-temperature and high-pressure technology,and the density of surface-modified diamond/Cu composites was less than 4 g cm^(-3).The W–WC–W_(2)C@diamond/Cu composites have a thermal diffusivity as high as 331 mm^(2)s^(-1),and their thermal expansion coefficient is as low as 1.76×10^(-6)K^(-1).The interface coherent structure of the gradient layer-coated diamond/copper composite can effectively improve the interface heat transport efficiency.展开更多
The electrode material is regarded as one of the key factors that determine the performance of lithium-ion batteries(LIBs).However,it is still a challenge to search for an anode material with large capacity,low diffus...The electrode material is regarded as one of the key factors that determine the performance of lithium-ion batteries(LIBs).However,it is still a challenge to search for an anode material with large capacity,low diffusion barrier,and good stability.In the present work,two new CrP_(2) monolayers(Pmmn-CrP_(2) and Pmma-CrP_(2)) are predicted by means of first principles swarm structure search.Our study shows that both the two CrP_(2) monolayers have high dynamical and thermal stability,as well as excellent electron conductivity.Additionally,Pmmn-CrP_(2) exhibits a remarkably high storage capacity of 705 mA·h·g^(-1) for Li,meanwhile the diffusion energy barrier of Li on the surface of this monolayer is 0.21 eV,ensuring it as a high-performance anode material for LIBs.We hope that our study will inspire researchers to search for new-type two-dimensional(2D) transition metal phosphides for the electrode materials of LIB s.展开更多
Wheat embryo globulin(WEG)has been proven to possess multiple biological activities,including antioxidative properties,immunomodulatory,and so on.Aged mouse model were established by subcutaneous injection of D-galact...Wheat embryo globulin(WEG)has been proven to possess multiple biological activities,including antioxidative properties,immunomodulatory,and so on.Aged mouse model were established by subcutaneous injection of D-galactose(D-gal),and the effects of WEG on learning,memory,and antioxidant capacity in aging mice were explored through behavioural tests and antioxidant enzyme activities determination.Compared with the Model group,WEG improved the percentage of the platform quadrant,increased the number of crossing platforms,and enhanced the identification indexs.WEG also increased total antioxidant capacity(T-AOC),superoxide dismutase(SOD),and glutathione peroxidase(GSH-Px)activities in the liver and brains of aging mice,and reduced malondialdehyde(MDA)content.Pathological observations indicated that WEG protected against damage to brain in D-gal-induced aging mice.These results effectively revealed that WEG not only improved the abilities of learning and memory,and the cognitive impairment,but also delayed the aging process of the D-gal-induced mice.展开更多
The properties of droplets produced by existing on-demand injection systems are typically determined by the nozzle diameter,i.e.,only droplets with size larger than this diameter can be obtained.To solve this problem,...The properties of droplets produced by existing on-demand injection systems are typically determined by the nozzle diameter,i.e.,only droplets with size larger than this diameter can be obtained.To solve this problem,a system for electricfield-driven droplet injection and deposition was developed,and the related performances were compared with those of a standard pneumatic system.The results show that the diameter of droplets gen-erated accordingly can be significantly smaller than the nozzle diameter.In particular,the effects of frequency and duty ratio on the number of droplets were studied by assuming microcrystalline wax as work material.A deposi-tion matrix was obtained by using a nozzle with a diameter of 200μm.The average diameter of the matrix was 80.17μm with a standard deviation of 2.65μm and the average spacing was 301.25μm with a standard deviation of 6.80μm.Four deposition states after droplet injection were considered and verified under different velocities of F60,F10,F3,and F0.We also provide an explanation for the existence of a series of inclined columns showing up during the deposition processs.展开更多
Lead-free inorganic copper-silver-bismuth-halide materials have attracted more and more attention due to their environmental friendliness,high element abundance,and low cost.Here,we developed a strategy of one-step ga...Lead-free inorganic copper-silver-bismuth-halide materials have attracted more and more attention due to their environmental friendliness,high element abundance,and low cost.Here,we developed a strategy of one-step gas-solid-phase diffusioninduced reaction to fabricate a series of bandgap-tunable Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI bilayer films due to the atomic diffusion effect for the first time.By designing and regulating the sputtered Cu/Ag/Bi metal film thickness,the bandgap of Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI could be reduced from 2.06 to 1.78 eV.Solar cells with the structure of FTO/TiO_(2)/Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI/carbon were constructed,yielding a champion power conversion efficiency of 2.76%,which is the highest reported for this class of materials owing to the bandgap reduction and the peculiar bilayer structure.The current work provides a practical path for developing the next generation of efficient,stable,and environmentally friendly photovoltaic materials.展开更多
The asymptotic stability of two species stochastic Lotka-Volterra model is explored in this paper. Firstly, the Lotka-Volterra model with random parameter is built and reduced into the equivalent deterministic system ...The asymptotic stability of two species stochastic Lotka-Volterra model is explored in this paper. Firstly, the Lotka-Volterra model with random parameter is built and reduced into the equivalent deterministic system by orthogonal polynomial approximation. Then, the linear stability theory and Routh-Hurwitz criterion for nonlinear deterministic systems are applied to the equivalent one. At last, at the aid of Lyapunov second method, we obtain that as the random intensity or statistical parameter of random variable is changed, the stability about stochastic Lotka-Volterra model is different from the deterministic system.展开更多
In this article, a partially linear single-index model /or longitudinal data is investigated. The generalized penalized spline least squares estimates of the unknown parameters are suggested. All parameters can be est...In this article, a partially linear single-index model /or longitudinal data is investigated. The generalized penalized spline least squares estimates of the unknown parameters are suggested. All parameters can be estimated simultaneously by the proposed method while the feature of longitudinal data is considered. The existence, strong consistency and asymptotic normality of the estimators are proved under suitable conditions. A simulation study is conducted to investigate the finite sample performance of the proposed method. Our approach can also be used to study the pure single-index model for longitudinal data.展开更多
In this paper, we investigate the well-known problem of a finite width strip with a single edge crack, which is useful in basic engineering and material science. By extending the configuration to a two-dimensional dec...In this paper, we investigate the well-known problem of a finite width strip with a single edge crack, which is useful in basic engineering and material science. By extending the configuration to a two-dimensional decagonal quasicrystal, we obtain the analytic solutions of modesⅠand Ⅱ using the transcendental function conformal mapping technique. Our calculation results provide an accurate estimate of the stress intensity factors K_Ⅰ and K_Ⅱ, which can be expressed in a quite simple form and are essential in the fracture theory of quasicrystals. Meanwhile, we suggest a generalized cohesive force model for the configuration to a two-dimensional decagonal quasicrystal. The results may provide theoretical guidance for the fracture theory of two-dimensional decagonal quasicrystals.展开更多
The carbon isotopic composition of organic matter from lake sediments has been extensively used to infer variations in productivity. In this paper, based on the study of the contents and δ13C values of organic matter...The carbon isotopic composition of organic matter from lake sediments has been extensively used to infer variations in productivity. In this paper, based on the study of the contents and δ13C values of organic matter in different types of lakes, it has been found that δ13C values of organic matter have different responses to lake productivity in different lakes. As to the lakes dominated by aqutic macrophytes such as Lake Caohai, organic matter becomes enriched in 13C with increasing productivity. As to the lakes dominated by aquatic algae such as Lake Chenghai, δ13C values of organic matter decrease with increasing productivity, and the degradation of aquatic algae is the main factor leading to the decrease of δ13C values of organic matter with increasing productivity. Therefore, we should be cautious to use the carbon isotopic composition of organic matter to deduce lake productivity.展开更多
In this paper, the extended finite element method (XFEM) is adopted to analyze the interaction between a single macroscopic inclusion and a single macroscopic crack as well as that between multiple macroscopic or micr...In this paper, the extended finite element method (XFEM) is adopted to analyze the interaction between a single macroscopic inclusion and a single macroscopic crack as well as that between multiple macroscopic or microscopic defects under thermal/mechanical load. The effects of different shapes of multiple inclusions on the material thermomechanical response are investigated, and the level set method is coupled with XFEM to analyze the interaction of multiple defects. Further, the discretized extended finite element approximations in relation to thermoelastic problems of multiple defects under displacement or temperature field are given. Also, the interfaces of cracks or materials are represented by level set functions, which allow the mesh assignment not to conform to crack or material interfaces. Moreover, stress intensity factors of cracks are obtained by the interaction integral method or the M-integral method, and the stress/strain/stiffness fields are simulated in the case of multiple cracks or multiple inclusions. Finally, some numerical examples are provided to demonstrate the accuracy of our proposed method.展开更多
In this paper,microwave sterilization craft of solid culture medium in fungus growth is studied.The results show that microwave not only can be used to sterilize the micro-organisms which is useless for fungus growth ...In this paper,microwave sterilization craft of solid culture medium in fungus growth is studied.The results show that microwave not only can be used to sterilize the micro-organisms which is useless for fungus growth in the solid culture medium,but also has positive effect on fungus growth;and the sterilization process is featured with shorter time and higher efficiency compared with the traditional method.展开更多
The environmentally friendly Cu_(2)ZnSn(S,Se)_(4)(CZTSSe) compounds are promising direct bandgap materials for application in thin film solar cells, but the spontaneous surface defects disordering would lead to large ...The environmentally friendly Cu_(2)ZnSn(S,Se)_(4)(CZTSSe) compounds are promising direct bandgap materials for application in thin film solar cells, but the spontaneous surface defects disordering would lead to large open-circuit voltage deficit(V_(oc,deficit)) and significantly limit kesterite photovoltaics performance,primarily arising from the generated more recombination centers and insufficient p to n conversion at p-n junction. Herein, we establish a surface defects ordering structure in CZTSSe system via local substitution of Cu by Ag to suppress disordered Cu_(Zn) defects and generate benign n-type Zn_(Ag) donors. Taking advantage of the decreased annealing temperature of Ag F post deposition treatment(PDT), the high concentration of Ag incorporated into surface absorber facilitates the formation of surface ordered defect environment similar to that of efficient CIGS PV. The manipulation of highly doped surface structure could effectively reduce recombination centers, increase depletion region width and enlarge the band bending near p-n junction. As a result, the Ag F-PDT device finally achieves maximum efficiency of 12.34% with enhanced V_(oc) of 0.496 V. These results offer a new solution route in surface defects and energy-level engineering, and open the way to build up high quality p-n junction for future development of kesterite technology.展开更多
In this paper, Pt-Co_3O_4 nanocomposite was synthesized by a sol gel process combined with electrodeposition method. Its electrocatalytic activity towards methanol oxidation was investigated at room temperature using ...In this paper, Pt-Co_3O_4 nanocomposite was synthesized by a sol gel process combined with electrodeposition method. Its electrocatalytic activity towards methanol oxidation was investigated at room temperature using cyclic voltammetry(CV), electrochemical impedance spectroscopy(EIS) and current density time curve. It is found that the resultant Pt-Co_3O_4 catalysts with minute amount of Pt exhibite attractive electrocatalytic activity for methanol oxidation reaction(MOR) but with a high resistance CO poisoning due to the synergistic effects from Pt and Co_3O_4. Together with the low manufacturing cost of Co_3O_4, the reported nanostructured Pt-Co_3O_4 catalyst is expected to be a promising electrode material for direct methanol fuel cells(DMFC).展开更多
文摘Research purpose:This study implemented somatosensory music therapy on patients with depressive disorders,and explored the effects of somatosensory music therapy on the degree of depression,positive and negative emotions,intuitive stress and autonomic nervous function of patients.Research method:We collected 66 patients diagnosed with depression from the Department of Psychological Medicine of Henan Provincial People’s Hospital,and divided them into a control group and an intervention group according to the random number table,with 33 people in each group.The control group received routine psychiatric treatment and nursing.On the basis of the control group,the intervention group received somatosensory music therapy 3 times a week,30 min each time,for 4 consecutive weeks.The Hamilton Depression Scale,Positive and Negative Emotion Scale,Perceived Stress Scale,and Heart Rate Variability Index were collected and analyzed at baseline(T0),2 weeks after treatment(T1)and 4 weeks after treatment(T2).Research results:After 4 weeks of treatment,the HAMD scores of the two groups decreased to varying degrees,and the difference between the groups was statistically significant(p<0.05).After 4 weeks of treatment,the scores of positive emotions in both groups increased to varying degrees,and the scores of negative emotions increased to varying degrees.The scores decreased to varying degrees,and there were statistically significant differences between the positive and negative emotion groups(p<0.05).After 4 weeks of treatment,the CPSS scores of the two groups decreased to varying degrees,and the difference between the two groups was statistically significant(p<0.05).Analyzing the main effect of intervention factors alone,after 4 weeks of treatment,SDNN and RMSSD indexes all increased to varying degrees,and the degree of increase in the intervention group was greater than that in the control group,and the difference between the groups was statistically significant(p<0.05).Research conclusion:assisting somatosensory music therapy for patients with depressive disorders can improve depressive symptoms,increase positive emotions,reduce negative emotions,and reduce perceived stress.These are beneficial to restore the balance of autonomic nervous system,and are effective for the treatment of depression.
基金Sponsored by Social Science Planning Project of Xuchang in 2018
文摘Starting from the purpose and current situation of the implementation of action of "Xuchang being full of green",this study analyzed the problems existing in the implementation of action of "Xuchang being full of green" and discussed the implementation plan of action of "Xuchang being full of green" from two aspects of macro strategy and node promotion strategy,hoping to promote the construction of ecological garden cities in Xuchang and other cities in China.
基金Under the auspices of Natural Science Foundation of China(No.41971166)。
文摘Urban functional area(UFA)is a core scientific issue affecting urban sustainability.The current knowledge gap is mainly reflected in the lack of multi-scale quantitative interpretation methods from the perspective of human-land interaction.In this paper,based on multi-source big data include 250 m×250 m resolution cell phone data,1.81×105 Points of Interest(POI)data and administrative boundary data,we built a UFA identification method and demonstrated empirically in Shenyang City,China.We argue that the method we built can effectively identify multi-scale multi-type UFAs based on human activity and further reveal the spatial correlation between urban facilities and human activity.The empirical study suggests that the employment functional zones in Shenyang City are more concentrated in central cities than other single functional zones.There are more mix functional areas in the central city areas,while the planned industrial new cities need to develop comprehensive functions in Shenyang.UFAs have scale effects and human-land interaction patterns.We suggest that city decision makers should apply multi-sources big data to measure urban functional service in a more refined manner from a supply-demand perspective.
基金the Natural Science Foundation of Henan Province(Grant Nos.212300410388 and 212300410238)the Scientific Research Innovation Team of Xuchang University(Grant No.2022CXTD005)+2 种基金the National Scientific Research Project Cultivation Fund of Xuchang University(Grant No.2022GJPY001)the Key Research Project in Universities of Henan Province(Grant No.23B140010)the“316"Project Plan of Xuchang University.
文摘Non-Hermitian dissipation dynamics,capable of turning the conventionally detrimental decoherence effects to useful resources for state engineering,is highly attractive to quantum information processing.In this work,an effective scheme is developed for implementing fast population transfer with a superconducting qutrit via the non-Hermitian shortcut to adiabaticity(STA).We first deal with aΛ-configuration interaction between the qutrit and microwave drivings,in which the dephasing-assisted qubit state inversion requiring an overlarge dephasing rate is constructed non-adiabatically.After introducing a feasible ancillary driving that directly acts upon the qubit states,the target state transfer can be well realized but with an accessible qubit dephasing rate.Moreover,a high fidelity could be numerically obtained in the considered system.The strategy could provide a new route towards the non-Hermitian shortcut operations on superconducting quantum circuits.
基金financially the National Natural Science Foundation of China(U2004175,51902086 and 62222402)China Postdoctoral Science Foundation(2022M711036)the Key Scientific Research Project plan of the University in Henan Province(22A430002)。
文摘Exploring materials with high electrochemical activity is of keen interest for electrochemistry-controlled optical and energy storage devices.However,it remains a great challenge for transition metal oxides to meet this feature due to their low electron conductivity and insufficient reaction sites.Here,we propose a type of transition metal phosphate(NiHPO_(4)·3H_(2)O,NHP)by a facile and scalable electrodeposition method,which can achieve the capability of efficient ion accommodation and injection/extraction for electrochromic energy storage applications.Specifically,the NHP film with an ultra-high transmittance(approach to 100%)achieves a large optical modulation(90.8%at 500 nm),high coloration efficiency(75.4 cm^(2)C^(-1)at 500 nm),and a high specific capacity of 47.8 mAh g^(-1)at 0.4 A g^(-1).Furthermore,the transformation mechanism of NHP upon electrochemical reaction is systematically elucidated using in situ and ex situ techniques.Ultimately,a large-area electrochromic smart window with 100 cm^(2)is constructed based on the NHP electrode,displaying superior electrochromic energy storage performance in regulating natural light and storing electrical charges.Our findings may open up new strategies for developing advanced electrochromic energy storage materials and smart windows.
基金National Natural Science Foundation of China(Grant No.52072327)the China National Key R&D Program(2021YFB3701802)+6 种基金Scientific and Technological Projects of Henan Province(No.232102231050)the Higher Education and Teaching Reformation Project(2014SJGLX064)the Project for Work-station of Zhongyuan scholars of Henan Province(Nos.214400510002,224400510023)the Science and Technology Major Project of Henan Province(No.221100230300)the Postgraduate Education Reform and QualityAcademic Degrees&Graduate Education Reform Project of Henan Province(No.2021SJGLX060Y)the Postgraduate Education Reform and Quality Improvement Project of Henan Province(No.YJS2022JD34)the Science and Technology on Plasma Physics Laboratory(Grant No.JCKYS2021212010).
文摘With rapid developments in the field of very large-scale integrated circuits,heat dissipation has emerged as a significant factor that restricts the high-density integration of chips.Due to their high thermal conductivity and low thermal expansion coefficient,diamond/Cu composites have attracted considerable attention as a promising thermal management material.In this study,a surface tungsten carbide gradient layer coating of diamond particles has been realized using comprehensive magnetron sputtering technology and a heat treatment process.Diamond/Cu composites were prepared using high-temperature and high-pressure technology.The results show that,by adjusting the heat treatment process,tungsten carbide and di-tungsten carbide are generated by an in situ reaction at the tungsten–diamond interface,and W–WC–W_(2)C gradient layer-coated diamond particles were obtained.The diamond/Cu composites were sintered by high-temperature and high-pressure technology,and the density of surface-modified diamond/Cu composites was less than 4 g cm^(-3).The W–WC–W_(2)C@diamond/Cu composites have a thermal diffusivity as high as 331 mm^(2)s^(-1),and their thermal expansion coefficient is as low as 1.76×10^(-6)K^(-1).The interface coherent structure of the gradient layer-coated diamond/copper composite can effectively improve the interface heat transport efficiency.
基金Project supported by the National Natural Science Foundation of China(Grant No.11964006)the Science and Technology Foundation of Kaili University(Grant No.2022ZD06)the Specialized Research Fund for the Doctoral Program of Kaili University(Grant Nos.BS201601 and BS201702)。
文摘The electrode material is regarded as one of the key factors that determine the performance of lithium-ion batteries(LIBs).However,it is still a challenge to search for an anode material with large capacity,low diffusion barrier,and good stability.In the present work,two new CrP_(2) monolayers(Pmmn-CrP_(2) and Pmma-CrP_(2)) are predicted by means of first principles swarm structure search.Our study shows that both the two CrP_(2) monolayers have high dynamical and thermal stability,as well as excellent electron conductivity.Additionally,Pmmn-CrP_(2) exhibits a remarkably high storage capacity of 705 mA·h·g^(-1) for Li,meanwhile the diffusion energy barrier of Li on the surface of this monolayer is 0.21 eV,ensuring it as a high-performance anode material for LIBs.We hope that our study will inspire researchers to search for new-type two-dimensional(2D) transition metal phosphides for the electrode materials of LIB s.
基金funded by Zhongyuan Scholars in Henan Province(192101510004)Major Science and Technology Projects for Public Welfare of Henan Province(201300110300)+2 种基金Innovation Demonstration Special Project of Henan Province(201111110100)financially supported by Key Project Foundation of Natural Science Research of Universities of Henan Province in China(20A550004)Fundamental Research Funds for the Henan Provincial Colleges and Universities in Henan University of Technology(HAUT)and High-Level Talents Research Fund of HAUT(2018QNJH13,and 2018BS012)。
文摘Wheat embryo globulin(WEG)has been proven to possess multiple biological activities,including antioxidative properties,immunomodulatory,and so on.Aged mouse model were established by subcutaneous injection of D-galactose(D-gal),and the effects of WEG on learning,memory,and antioxidant capacity in aging mice were explored through behavioural tests and antioxidant enzyme activities determination.Compared with the Model group,WEG improved the percentage of the platform quadrant,increased the number of crossing platforms,and enhanced the identification indexs.WEG also increased total antioxidant capacity(T-AOC),superoxide dismutase(SOD),and glutathione peroxidase(GSH-Px)activities in the liver and brains of aging mice,and reduced malondialdehyde(MDA)content.Pathological observations indicated that WEG protected against damage to brain in D-gal-induced aging mice.These results effectively revealed that WEG not only improved the abilities of learning and memory,and the cognitive impairment,but also delayed the aging process of the D-gal-induced mice.
基金supported by the National Science Foundation of China(Grant Nos.51305128,52005059)Open Research Fund of State Key Laboratory of High-Performance Complex Manufacturing,and Central South University(Grant No.Kfkt2020-10)Key Scientific Research Project of Xuchang University(No.2023ZD001).
文摘The properties of droplets produced by existing on-demand injection systems are typically determined by the nozzle diameter,i.e.,only droplets with size larger than this diameter can be obtained.To solve this problem,a system for electricfield-driven droplet injection and deposition was developed,and the related performances were compared with those of a standard pneumatic system.The results show that the diameter of droplets gen-erated accordingly can be significantly smaller than the nozzle diameter.In particular,the effects of frequency and duty ratio on the number of droplets were studied by assuming microcrystalline wax as work material.A deposi-tion matrix was obtained by using a nozzle with a diameter of 200μm.The average diameter of the matrix was 80.17μm with a standard deviation of 2.65μm and the average spacing was 301.25μm with a standard deviation of 6.80μm.Four deposition states after droplet injection were considered and verified under different velocities of F60,F10,F3,and F0.We also provide an explanation for the existence of a series of inclined columns showing up during the deposition processs.
基金supported by National Natural Science Foundation of China(Grant No.52072327,62074052,61874159)Zhongyuan Thousand Talents(Zhongyuan Scholars)Program of Henan Province(202101510004)+6 种基金Higher Education and Teaching Reformation Project(2014SJGLX064)Academic Degrees&Graduate Education Reform Project of Henan Province(2021SJGLX060Y)Key research and development projects of Universities in Henan Province(20A140026)the Scientific Research Innovation Team of Xuchang University(2022CXTD008)Science and Technology Project of Henan Province(222102230009).L.Ding thanks the National Key Research and Development Program of China(2022YFB3803300)the open research fund of Songshan Lake Materials Laboratory(2021SLABFK02)the National Natural Science Foundation of China(21961160720).
文摘Lead-free inorganic copper-silver-bismuth-halide materials have attracted more and more attention due to their environmental friendliness,high element abundance,and low cost.Here,we developed a strategy of one-step gas-solid-phase diffusioninduced reaction to fabricate a series of bandgap-tunable Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI bilayer films due to the atomic diffusion effect for the first time.By designing and regulating the sputtered Cu/Ag/Bi metal film thickness,the bandgap of Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI could be reduced from 2.06 to 1.78 eV.Solar cells with the structure of FTO/TiO_(2)/Cu_(a)Agm_(1)Bim_(2)I_(n)/CuI/carbon were constructed,yielding a champion power conversion efficiency of 2.76%,which is the highest reported for this class of materials owing to the bandgap reduction and the peculiar bilayer structure.The current work provides a practical path for developing the next generation of efficient,stable,and environmentally friendly photovoltaic materials.
文摘The asymptotic stability of two species stochastic Lotka-Volterra model is explored in this paper. Firstly, the Lotka-Volterra model with random parameter is built and reduced into the equivalent deterministic system by orthogonal polynomial approximation. Then, the linear stability theory and Routh-Hurwitz criterion for nonlinear deterministic systems are applied to the equivalent one. At last, at the aid of Lyapunov second method, we obtain that as the random intensity or statistical parameter of random variable is changed, the stability about stochastic Lotka-Volterra model is different from the deterministic system.
基金Supported by the National Natural Science Foundation of China (10571008)the Natural Science Foundation of Henan (092300410149)the Core Teacher Foundationof Henan (2006141)
文摘In this article, a partially linear single-index model /or longitudinal data is investigated. The generalized penalized spline least squares estimates of the unknown parameters are suggested. All parameters can be estimated simultaneously by the proposed method while the feature of longitudinal data is considered. The existence, strong consistency and asymptotic normality of the estimators are proved under suitable conditions. A simulation study is conducted to investigate the finite sample performance of the proposed method. Our approach can also be used to study the pure single-index model for longitudinal data.
基金supported by the National Natural Science Foundation of China(Grant No.10802043)
文摘In this paper, we investigate the well-known problem of a finite width strip with a single edge crack, which is useful in basic engineering and material science. By extending the configuration to a two-dimensional decagonal quasicrystal, we obtain the analytic solutions of modesⅠand Ⅱ using the transcendental function conformal mapping technique. Our calculation results provide an accurate estimate of the stress intensity factors K_Ⅰ and K_Ⅱ, which can be expressed in a quite simple form and are essential in the fracture theory of quasicrystals. Meanwhile, we suggest a generalized cohesive force model for the configuration to a two-dimensional decagonal quasicrystal. The results may provide theoretical guidance for the fracture theory of two-dimensional decagonal quasicrystals.
基金supported by the National Basic Research Program of China (Grant No. 2006CB403201)the National Natural Science Foundation of China (Grant No. 40673068)
文摘The carbon isotopic composition of organic matter from lake sediments has been extensively used to infer variations in productivity. In this paper, based on the study of the contents and δ13C values of organic matter in different types of lakes, it has been found that δ13C values of organic matter have different responses to lake productivity in different lakes. As to the lakes dominated by aqutic macrophytes such as Lake Caohai, organic matter becomes enriched in 13C with increasing productivity. As to the lakes dominated by aquatic algae such as Lake Chenghai, δ13C values of organic matter decrease with increasing productivity, and the degradation of aquatic algae is the main factor leading to the decrease of δ13C values of organic matter with increasing productivity. Therefore, we should be cautious to use the carbon isotopic composition of organic matter to deduce lake productivity.
基金supported by the National Natural Science Foundation of China (Grants 11471262, 50976003, 51136005)
文摘In this paper, the extended finite element method (XFEM) is adopted to analyze the interaction between a single macroscopic inclusion and a single macroscopic crack as well as that between multiple macroscopic or microscopic defects under thermal/mechanical load. The effects of different shapes of multiple inclusions on the material thermomechanical response are investigated, and the level set method is coupled with XFEM to analyze the interaction of multiple defects. Further, the discretized extended finite element approximations in relation to thermoelastic problems of multiple defects under displacement or temperature field are given. Also, the interfaces of cracks or materials are represented by level set functions, which allow the mesh assignment not to conform to crack or material interfaces. Moreover, stress intensity factors of cracks are obtained by the interaction integral method or the M-integral method, and the stress/strain/stiffness fields are simulated in the case of multiple cracks or multiple inclusions. Finally, some numerical examples are provided to demonstrate the accuracy of our proposed method.
基金Supported by the Natural Science Research Project of the Education Department of Henan Province(No.2009B210023)~~
文摘In this paper,microwave sterilization craft of solid culture medium in fungus growth is studied.The results show that microwave not only can be used to sterilize the micro-organisms which is useless for fungus growth in the solid culture medium,but also has positive effect on fungus growth;and the sterilization process is featured with shorter time and higher efficiency compared with the traditional method.
基金supported by the National Natural Science Foundation of China(61874159,62074052,61974173,52072327,51702085 and 51802081)the Joint Talent Cultivation Funds of NSFC-HN(U1704151 and U1904192)+1 种基金the Zhongyuan Thousand Talents(Zhongyuan Scholars)Program of Henan Province(202101510004)the Science and Technology Innovation Talents in Universities of Henan Province(21HASTIT023)。
文摘The environmentally friendly Cu_(2)ZnSn(S,Se)_(4)(CZTSSe) compounds are promising direct bandgap materials for application in thin film solar cells, but the spontaneous surface defects disordering would lead to large open-circuit voltage deficit(V_(oc,deficit)) and significantly limit kesterite photovoltaics performance,primarily arising from the generated more recombination centers and insufficient p to n conversion at p-n junction. Herein, we establish a surface defects ordering structure in CZTSSe system via local substitution of Cu by Ag to suppress disordered Cu_(Zn) defects and generate benign n-type Zn_(Ag) donors. Taking advantage of the decreased annealing temperature of Ag F post deposition treatment(PDT), the high concentration of Ag incorporated into surface absorber facilitates the formation of surface ordered defect environment similar to that of efficient CIGS PV. The manipulation of highly doped surface structure could effectively reduce recombination centers, increase depletion region width and enlarge the band bending near p-n junction. As a result, the Ag F-PDT device finally achieves maximum efficiency of 12.34% with enhanced V_(oc) of 0.496 V. These results offer a new solution route in surface defects and energy-level engineering, and open the way to build up high quality p-n junction for future development of kesterite technology.
基金supported by National Natural Science Foundation of China (Grant No. 21273192, 91023010, 61204009, 21303153)Innovation Scientists and Technicians Troop Construction Projects of Henan Province (Grant No. 104100510001)+1 种基金the Program for Science & Technology Innovation Talents in Universities of Henan Province (2008 HASTIT016)Henan Province Science and Technology Key Project (Grant No. 082102230036 and 122102210479)
文摘In this paper, Pt-Co_3O_4 nanocomposite was synthesized by a sol gel process combined with electrodeposition method. Its electrocatalytic activity towards methanol oxidation was investigated at room temperature using cyclic voltammetry(CV), electrochemical impedance spectroscopy(EIS) and current density time curve. It is found that the resultant Pt-Co_3O_4 catalysts with minute amount of Pt exhibite attractive electrocatalytic activity for methanol oxidation reaction(MOR) but with a high resistance CO poisoning due to the synergistic effects from Pt and Co_3O_4. Together with the low manufacturing cost of Co_3O_4, the reported nanostructured Pt-Co_3O_4 catalyst is expected to be a promising electrode material for direct methanol fuel cells(DMFC).