The diffusion and thermite reaction process of Al/NiO nanothermite composed of Al nanofilm and NiO nano honeycomb are investigated by molecular dynamics simulations in combination with the Reax FF. The diffusion and t...The diffusion and thermite reaction process of Al/NiO nanothermite composed of Al nanofilm and NiO nano honeycomb are investigated by molecular dynamics simulations in combination with the Reax FF. The diffusion and thermite reaction are characterized by measuring energy release, adiabatic reaction temperature, and activation energy. Based on time evolution of atomic configuration and mean square displacement, the initialization of the thermite reaction process of Al/NiO nanothermite results from the diffusion of Al atoms. Under the microcanonical ensemble, it is found that the adiabatic reaction temperature of the thermite reaction process of Al/NiO nanothermite reaches over 5500 K, and activation energy is 8.43 k J/mol. The release energy of the thermite reaction process of Al/NiO nanothermite is 2.2 k J/g, which is in accordance with the available experimental value. With the same initial temperature, the adiabatic reaction temperature of the thermite reaction process of Al/NiO nanothermite has a tendency to decrease dramatically as the equivalence ratio increases. On the basis of chemical bond analysis, the initial temperature and equivalence ratio have great effects on the thermite reaction process, but do not significantly affect the average length of Al–Ni nor Al–O bond. Overall, the thermite reaction of film-honeycomb Al/NiO nanothermite is a complicated process instead of a theoretical equation.展开更多
The geometry,stability,binding energy and electronic properties of(SiO2)n and Ge(SiO2)n clusters(n = 7) have been investigated by Density functional theory(DFT).The results show that the lowest energy structures of Ge...The geometry,stability,binding energy and electronic properties of(SiO2)n and Ge(SiO2)n clusters(n = 7) have been investigated by Density functional theory(DFT).The results show that the lowest energy structures of Ge(SiO2)n are obtained by adding one Ge on the end site of the O atom or the Si near end site of the O atom in(SiO2)n.The chemical activation of Ge-(SiO2)n is improved compared with(SiO2)n.The calculated second-order difference of energies and fragmentation energies show that the Ge(SiO2)n clusters with n = 2 or 5 are stable.展开更多
A dark matter mechanism within the framework of the standard model (SM) of particle physics is proposed in this article that the essence of dark matter may be the excited virtual particle field by the gravitational fi...A dark matter mechanism within the framework of the standard model (SM) of particle physics is proposed in this article that the essence of dark matter may be the excited virtual particle field by the gravitational field of ordinary matter, which contains virtual photons, virtual positive and negative electron pairs, virtual gluons, virtual positive and negative quark pairs, virtual neutrinos etc. In this mechanism, there are two basic assumptions: 1) the stronger the gravitational field of ordinary matter, the greater the excited energy (mass) density of virtual particle field;2) The excited virtual particle field is generally very weak in self-interaction. The virtual particle field excited by gravity can exhibit the properties of dark matter and may become a dark matter candidate. Based on this new dark matter mechanism, the hydrodynamic equations and cosmic perturbation equations describing cosmic matter are improved, and this may be meaningful for solving the challenges faced by the standard cosmological model (Lambda-CDM or LCDM) and developing and perfecting LCDM model.展开更多
We propose a catalytically activated duplication model to mimic the coagulation and duplication of the DNA polymer system under the catalysis of the primer RNA.In the model,two aggregates of the same species can coagu...We propose a catalytically activated duplication model to mimic the coagulation and duplication of the DNA polymer system under the catalysis of the primer RNA.In the model,two aggregates of the same species can coagulate themselves and a DNA aggregate of any size can yield a new monomer or double itself with the help of RNA aggregates.By employing the mean-field rate equation approach we analytically investigate the evolution behaviour of the system.For the system with catalysis-driven monomer duplications,the aggregate size distribution of DNA polymers a k (t) always follows a power law in size in the long-time limit,and it decreases with time or approaches a time-independent steady-state form in the case of the duplication rate independent of the size of the mother aggregates,while it increases with time increasing in the case of the duplication rate proportional to the size of the mother aggregates.For the system with complete catalysis-driven duplications,the aggregate size distribution a k (t) approaches a generalized or modified scaling form.展开更多
This paper solves numerically the full time-dependent Schrdinger equation based on the rigid rotor model, and proposes a novel strategy to determine the optimal time delay of the two laser pulses to manipulate the m...This paper solves numerically the full time-dependent Schrdinger equation based on the rigid rotor model, and proposes a novel strategy to determine the optimal time delay of the two laser pulses to manipulate the molecular selective alignment. The results illustrate that the molecular alignment generated by the first pulse can be suppressed or enhanced selectively, the relative populations of even and odd rotational states in the final rotational wave packet can be manipulated selectively by precisely inserting the peak of the second laser pulse at the time when the slope for the alignment parameter by the first laser locates a local maximum for the even rotational states and a local minimum for the odds, and vice versa. The selective alignment can be further optimised by selecting the intensity ratio of the two laser pulses on the condition that the total laser intensity and pulse duration are kept constant.展开更多
We propose a catalytically activated replication-decline model of three species, in which two aggregates of the same species can coagulate themselves, an A aggregate of any size can replicate itself with the help of B...We propose a catalytically activated replication-decline model of three species, in which two aggregates of the same species can coagulate themselves, an A aggregate of any size can replicate itself with the help of B aggregates, and the decline of A aggregate occurs under the catalysis of C aggregates. By means of mean-field rate equations, we derive the asymptotic solutions of the aggregate size distribution ak(t) of species A, which is found to depend strongly on the competition among three mechanisms: the self-coagulation of species A, the replication of species A catalyzed by species B, and the decline of species A catalyzed by species C. When the self-coagulation of species A dominates the system, the aggregate size distribution ak(t) satisfies the conventional scaling form. When the catalyzed replication process dominates the system, ak(t) takes the generalized scaling form. When the catalyzed decline process dominates the system, ak(t) approaches the modified scaling form.展开更多
We propose a catalytically activated aggregation-fragmentation model of three species,in which two clusters of species A can coagulate into a larger one under the catalysis of B clusters;otherwise,one cluster of speci...We propose a catalytically activated aggregation-fragmentation model of three species,in which two clusters of species A can coagulate into a larger one under the catalysis of B clusters;otherwise,one cluster of species A will fragment into two smaller clusters under the catalysis of C clusters.By means of mean-field rate equations,we derive the asymptotic solutions of the cluster-mass distributions a k (t) of species A,which is found to depend strongly on the competition between the catalyzed aggregation process and the catalyzed fragmentation process.When the catalyzed aggregation process dominates the system,the cluster-mass distribution a k (t) satisfies the conventional scaling form.When the catalyzed fragmentation process dominates the system,the scaling description of a k (t) breaks down completely and the monodisperse initial condition of species A would not be changed in the long-time limit.In the marginal case when the effects of catalyzed aggregation and catalyzed fragmentation counteract each other,a k (t) takes the modified scaling form and the system can eventually evolve to a steady state.展开更多
二很少周期脉搏导致的 D <SUB>2</SUB> 的动态排列被基于一个僵硬转子模型数字地解决时间依赖者 Schrodinger 方程调查。只要在二之间的时间延期搏动, D <SUB>2</SUB>的排列能被二很少周期脉搏与由单个很少周...二很少周期脉搏导致的 D <SUB>2</SUB> 的动态排列被基于一个僵硬转子模型数字地解决时间依赖者 Schrodinger 方程调查。只要在二之间的时间延期搏动, D <SUB>2</SUB>的排列能被二很少周期脉搏与由单个很少周期脉搏可完成的水平相比提高的结果表演适当地被选择,并且二激光的脉搏持续时间在 D <SUB>2</SUB>分子的排列过程起一个重要作用。展开更多
<正>This paper discusses the masses and possible members of 2~1S_0 and 2~3S_1 meson multiplets in the framework of meson-meson mixing and Regge phenomenology.For the 2~1S_0 meson nonet,K~*(1460) may be the obser...<正>This paper discusses the masses and possible members of 2~1S_0 and 2~3S_1 meson multiplets in the framework of meson-meson mixing and Regge phenomenology.For the 2~1S_0 meson nonet,K~*(1460) may be the observed state of the 2~1S_0 isodoublet with a mass of 1400 MeV and the mass ofω(1420) is 1412 MeV.For the 2~3S_1 meson nonet,K~*(1410) seems too light to be the 2~3S_1 ns member.The fact that the agreement between the present findings and those given by experiments and other different approaches is satisfactory implies that the assignments in this paper may be reasonable.展开更多
Zinc telluride/reduced graphene oxide(ZnTe/RGO) nanocomposites are synthesized by a one-pot, facile,solvothermal process using hydrazine hydrate as the reducing agent. Hydrazine hydrate not only promoted the formation...Zinc telluride/reduced graphene oxide(ZnTe/RGO) nanocomposites are synthesized by a one-pot, facile,solvothermal process using hydrazine hydrate as the reducing agent. Hydrazine hydrate not only promoted the formation of ZnTe nanoparticles but also reduced GO to RGO. The formation of ZnTe/RGO is demonstrated by different techniques. In addition, the experimental results suggest a possible formation mechanism of these nanocomposites. Finally, due to the transfer of the photo-generated electrons between ZnTe and RGO resulting in low electrons/holes recombination, the as-prepared nanocomposites of ZnTe/RGO exhibited strongly enhanced photocatalytic activity for the bleaching of methyl blue(MB)dye under visible light irradiation.展开更多
Au-Ag alloy nanoparticles with different cavity sizes have great potential for improving photocatalytic performance due to their tunable plasmon effect.In this study,galvanic replacement was combined with co-reduction...Au-Ag alloy nanoparticles with different cavity sizes have great potential for improving photocatalytic performance due to their tunable plasmon effect.In this study,galvanic replacement was combined with co-reduction with the reaction kinetics processes regulated to rapidly synthesize Au-Ag hollow alloy nanoparticles with tunable cavity sizes.The position of the localized surface plasmon resonance(LSPR)peak could be effectively adjusted between 490 nm and 713 nm by decreasing the cavity size of the Au-Ag hollow nanoparticles from 35 nm to 20 nm.The plasmon-enhanced photocatalytic H2 evolution of alloy nanoparticles with different cavity sizes was investigated.Compared with pure P25(TiO2),intact and thin-shelled Au-Ag hollow nanoparticles(HNPs)-supported photocatalyst exhibited an increase in the photocatalytic H2 evolution rate from 0.48μmol h^−1 to 4μmol h^−1 under full-spectrum irradiation.This improved photocatalytic performance was likely due to the plasmon-induced electromagnetic field effect,which caused strong photogenerated charge separation,rather than the generation of hot electrons.展开更多
Using the reductive perturbation method,we investigate the small amplitude nonlinear acoustic wave in a collisional self-gravitating dusty plasma.The result shows that the small amplitude dust acoustic wave can be exp...Using the reductive perturbation method,we investigate the small amplitude nonlinear acoustic wave in a collisional self-gravitating dusty plasma.The result shows that the small amplitude dust acoustic wave can be expressed by a modified Korteweg-de Vries equation,and the nonlinear wave is instable because of the collisions between the neutral gas molecules and the charged particles.展开更多
Single molecule magnets(SMMs) with large magnetic anisotropy energy(MAE) have great potential applications in magnetic recording.Using the first-principles calculations,we investigate the MAE of 5 d transition metal-p...Single molecule magnets(SMMs) with large magnetic anisotropy energy(MAE) have great potential applications in magnetic recording.Using the first-principles calculations,we investigate the MAE of 5 d transition metal-porphyrin-based SMMs by using the PBE and PBE+U with different U values,respectively.The results indicate that W-P,Re-P,Os-P,and Ir-P possess the considerably large MAE among 5 d TM-P SMMs.Furthermore,the MAE of 5 d TM-P can be facilely manipulated by tensile strain.The reduction of the absolute value of MAE for Ir-P molecule caused by tensile strain makes it easier to implement the writing operation.The decreasing of the occupation number of minority-spin channels of Ir-d_(x^(2)-y^(2)) orbital leads the MAE to decrease when the tensile strain increases.展开更多
Dendrites growth,chemical corrosion,and hydrogen evolution reaction(HER)on zinc anodes are the main barriers for the development of aqueous zinc-ion batteries(AZIBs).Constructing interfacial protec-tive layer is an ef...Dendrites growth,chemical corrosion,and hydrogen evolution reaction(HER)on zinc anodes are the main barriers for the development of aqueous zinc-ion batteries(AZIBs).Constructing interfacial protec-tive layer is an effective way to alleviate the side reactions on the anodes.Herein,Cu/Ti_(3)C_(2)Cl_(2)MXene(CMX)with high zincophilic and hydrophobic property is prepared by the lewis molten salts etching method,and the CMX interface protection layer is constructed by a simple spin coating.The CMX coat-ing layer can provide abundant nucleation sites and uniformize the charge distribution through the zin-cophilic Ti_(3)C_(2)Cl_(2)MXene matrix,leading to homogenous Zn deposition.In addition,the hydrophobic coat-ing contained anti-corrosive Cu nanoparticles can prevent the Zn anode from the electrolyte,beneficial for suppressing the chemical corrosion and HER.Therefore,the stable and reversible Zn plating/stripping is achieved for the Zn anode coated by the CMX,which exhibits the lifespan of over 1400 h at 0.5 mA cm^(−2),and even can steadily run for 700 h with 65 mV at 10 mA cm^(−2).Furthermore,CMX@Zn shows a high coulombic efficiency of over 100%for 3800 cycles,which indicates that the CMX@Zn electrode has excellent stability and reversibility of Zn stripping/plating.The full batteries assembled with ZnCoMnO/C(ZCM)cathodes also exhibits higher capacity(450.6 mAh g^(−1)at 0.1 A g^(−1))and cycle stability(capacity retention of 70%after 1500 cycles).This work enhanced the lifespan of AZIBs and broaden the research of multifunctional coating layer to other secondary batteries based on metal anodes.展开更多
For zinc air batteries,a non-noble metal-based electrocatalyst with a high performance and stability in oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)is imperative in application.Herein,a catalyst ba...For zinc air batteries,a non-noble metal-based electrocatalyst with a high performance and stability in oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)is imperative in application.Herein,a catalyst based on FeCo-N encapsuled in nitrogen-doped carbon nanotubes has been prepared,which provides an implementable method to design controlled structures with excellent bifunction al electrocatalytic activities.By adjusting the molar ratio of two metals,the synthesized FeCo-N-C catalyst delivers a competitive ORR and OER performance compared with commercial Pt/C and IrO_(2),performing a low overvoltage gap between ORR(E_(1/2))and OER(E_(j=10))of 0.8 V.Moreover,as a promising cathode in zinc air battery,the FeCo-N-C catalyst possesses an affirmative stability of over 100 h and large power density(129 mW·cm^(-2)).This work demonstrates that FeCo-N-C is one of the most promising catalysts for zinc air batteries and provides a possibility for exploration of batteries with high stability by adjusting the molar ratio of metals in the catalysts.展开更多
ZnO nanocone arrays(NCAs)decorated with black TiO2 nanoparticles(BTiO2 NPs)were uniformly anchored on the surface of carbon cloth(CC)directly by a simply electrochemical deposition method.Thus a novel B-TiO2 NPs/ZnO N...ZnO nanocone arrays(NCAs)decorated with black TiO2 nanoparticles(BTiO2 NPs)were uniformly anchored on the surface of carbon cloth(CC)directly by a simply electrochemical deposition method.Thus a novel B-TiO2 NPs/ZnO NCAs-CC hierarchical heterostructure was formed.It displayed superior performance and achieved a higher photocurrent over 0.4 mA·cm^-2 before the onset of the dark current,attributed to the separation of the photogenerated electron-hole pair.Based on the B-TiO2 NPs/ZnO NCAs-CC heterostructure,the catalyst was fabricated for promoting the separation of charge carriers.Moreover,the introduction of Ti^3+ and oxygen vacancies on the surface of TiO2 NPs expanded the absorption band edge and enhanced the electrical conductivity as well as the charge transportation on the catalytic surface.It indicates that the B-TiO2 NPs/ZnO NCAs-CC composite is beneficial to the improvement of the photoelectrochemical(PEC)activity.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11374217 and 21363019)
文摘The diffusion and thermite reaction process of Al/NiO nanothermite composed of Al nanofilm and NiO nano honeycomb are investigated by molecular dynamics simulations in combination with the Reax FF. The diffusion and thermite reaction are characterized by measuring energy release, adiabatic reaction temperature, and activation energy. Based on time evolution of atomic configuration and mean square displacement, the initialization of the thermite reaction process of Al/NiO nanothermite results from the diffusion of Al atoms. Under the microcanonical ensemble, it is found that the adiabatic reaction temperature of the thermite reaction process of Al/NiO nanothermite reaches over 5500 K, and activation energy is 8.43 k J/mol. The release energy of the thermite reaction process of Al/NiO nanothermite is 2.2 k J/g, which is in accordance with the available experimental value. With the same initial temperature, the adiabatic reaction temperature of the thermite reaction process of Al/NiO nanothermite has a tendency to decrease dramatically as the equivalence ratio increases. On the basis of chemical bond analysis, the initial temperature and equivalence ratio have great effects on the thermite reaction process, but do not significantly affect the average length of Al–Ni nor Al–O bond. Overall, the thermite reaction of film-honeycomb Al/NiO nanothermite is a complicated process instead of a theoretical equation.
基金Project supported by the foundation start up for high level talents of Shihezi university (No. RCZX200747)
文摘The geometry,stability,binding energy and electronic properties of(SiO2)n and Ge(SiO2)n clusters(n = 7) have been investigated by Density functional theory(DFT).The results show that the lowest energy structures of Ge(SiO2)n are obtained by adding one Ge on the end site of the O atom or the Si near end site of the O atom in(SiO2)n.The chemical activation of Ge-(SiO2)n is improved compared with(SiO2)n.The calculated second-order difference of energies and fragmentation energies show that the Ge(SiO2)n clusters with n = 2 or 5 are stable.
文摘A dark matter mechanism within the framework of the standard model (SM) of particle physics is proposed in this article that the essence of dark matter may be the excited virtual particle field by the gravitational field of ordinary matter, which contains virtual photons, virtual positive and negative electron pairs, virtual gluons, virtual positive and negative quark pairs, virtual neutrinos etc. In this mechanism, there are two basic assumptions: 1) the stronger the gravitational field of ordinary matter, the greater the excited energy (mass) density of virtual particle field;2) The excited virtual particle field is generally very weak in self-interaction. The virtual particle field excited by gravity can exhibit the properties of dark matter and may become a dark matter candidate. Based on this new dark matter mechanism, the hydrodynamic equations and cosmic perturbation equations describing cosmic matter are improved, and this may be meaningful for solving the challenges faced by the standard cosmological model (Lambda-CDM or LCDM) and developing and perfecting LCDM model.
基金supported by the National Natural Science Foundation of China (Grant Nos 10275048,10305009 and 10875086)by the Zhejiang Provincial Natural Science Foundation of China (Grant No 102067)
文摘We propose a catalytically activated duplication model to mimic the coagulation and duplication of the DNA polymer system under the catalysis of the primer RNA.In the model,two aggregates of the same species can coagulate themselves and a DNA aggregate of any size can yield a new monomer or double itself with the help of RNA aggregates.By employing the mean-field rate equation approach we analytically investigate the evolution behaviour of the system.For the system with catalysis-driven monomer duplications,the aggregate size distribution of DNA polymers a k (t) always follows a power law in size in the long-time limit,and it decreases with time or approaches a time-independent steady-state form in the case of the duplication rate independent of the size of the mother aggregates,while it increases with time increasing in the case of the duplication rate proportional to the size of the mother aggregates.For the system with complete catalysis-driven duplications,the aggregate size distribution a k (t) approaches a generalized or modified scaling form.
基金supported by the initial research fund for High Level Talents of Shihezi University,China (Grant No.RCZX200743)
文摘This paper solves numerically the full time-dependent Schrdinger equation based on the rigid rotor model, and proposes a novel strategy to determine the optimal time delay of the two laser pulses to manipulate the molecular selective alignment. The results illustrate that the molecular alignment generated by the first pulse can be suppressed or enhanced selectively, the relative populations of even and odd rotational states in the final rotational wave packet can be manipulated selectively by precisely inserting the peak of the second laser pulse at the time when the slope for the alignment parameter by the first laser locates a local maximum for the even rotational states and a local minimum for the odds, and vice versa. The selective alignment can be further optimised by selecting the intensity ratio of the two laser pulses on the condition that the total laser intensity and pulse duration are kept constant.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10875086 and 11145004)
文摘We propose a catalytically activated replication-decline model of three species, in which two aggregates of the same species can coagulate themselves, an A aggregate of any size can replicate itself with the help of B aggregates, and the decline of A aggregate occurs under the catalysis of C aggregates. By means of mean-field rate equations, we derive the asymptotic solutions of the aggregate size distribution ak(t) of species A, which is found to depend strongly on the competition among three mechanisms: the self-coagulation of species A, the replication of species A catalyzed by species B, and the decline of species A catalyzed by species C. When the self-coagulation of species A dominates the system, the aggregate size distribution ak(t) satisfies the conventional scaling form. When the catalyzed replication process dominates the system, ak(t) takes the generalized scaling form. When the catalyzed decline process dominates the system, ak(t) approaches the modified scaling form.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.10275048 and 10875086)by the Science Foundation of Shihezi University (Grant No.RCZX200745)
文摘We propose a catalytically activated aggregation-fragmentation model of three species,in which two clusters of species A can coagulate into a larger one under the catalysis of B clusters;otherwise,one cluster of species A will fragment into two smaller clusters under the catalysis of C clusters.By means of mean-field rate equations,we derive the asymptotic solutions of the cluster-mass distributions a k (t) of species A,which is found to depend strongly on the competition between the catalyzed aggregation process and the catalyzed fragmentation process.When the catalyzed aggregation process dominates the system,the cluster-mass distribution a k (t) satisfies the conventional scaling form.When the catalyzed fragmentation process dominates the system,the scaling description of a k (t) breaks down completely and the monodisperse initial condition of species A would not be changed in the long-time limit.In the marginal case when the effects of catalyzed aggregation and catalyzed fragmentation counteract each other,a k (t) takes the modified scaling form and the system can eventually evolve to a steady state.
文摘二很少周期脉搏导致的 D <SUB>2</SUB> 的动态排列被基于一个僵硬转子模型数字地解决时间依赖者 Schrodinger 方程调查。只要在二之间的时间延期搏动, D <SUB>2</SUB>的排列能被二很少周期脉搏与由单个很少周期脉搏可完成的水平相比提高的结果表演适当地被选择,并且二激光的脉搏持续时间在 D <SUB>2</SUB>分子的排列过程起一个重要作用。
文摘<正>This paper discusses the masses and possible members of 2~1S_0 and 2~3S_1 meson multiplets in the framework of meson-meson mixing and Regge phenomenology.For the 2~1S_0 meson nonet,K~*(1460) may be the observed state of the 2~1S_0 isodoublet with a mass of 1400 MeV and the mass ofω(1420) is 1412 MeV.For the 2~3S_1 meson nonet,K~*(1410) seems too light to be the 2~3S_1 ns member.The fact that the agreement between the present findings and those given by experiments and other different approaches is satisfactory implies that the assignments in this paper may be reasonable.
基金financially supported by the National Natural Science Foundation of China (Nos. 11164026, 51172193, 11504313, 51362026)the Natural Science Foundation for Distinguished Young Scholars of Xinjiang (No. 2013711007)
文摘Zinc telluride/reduced graphene oxide(ZnTe/RGO) nanocomposites are synthesized by a one-pot, facile,solvothermal process using hydrazine hydrate as the reducing agent. Hydrazine hydrate not only promoted the formation of ZnTe nanoparticles but also reduced GO to RGO. The formation of ZnTe/RGO is demonstrated by different techniques. In addition, the experimental results suggest a possible formation mechanism of these nanocomposites. Finally, due to the transfer of the photo-generated electrons between ZnTe and RGO resulting in low electrons/holes recombination, the as-prepared nanocomposites of ZnTe/RGO exhibited strongly enhanced photocatalytic activity for the bleaching of methyl blue(MB)dye under visible light irradiation.
基金supported by the National Natural Science Foundation of China(No.61704114)the Key areas of Science and Technology Program of Xinjiang Production and Construction Corps,China(No.2018AB004)the National Science Foundation(CBET-1803256).
文摘Au-Ag alloy nanoparticles with different cavity sizes have great potential for improving photocatalytic performance due to their tunable plasmon effect.In this study,galvanic replacement was combined with co-reduction with the reaction kinetics processes regulated to rapidly synthesize Au-Ag hollow alloy nanoparticles with tunable cavity sizes.The position of the localized surface plasmon resonance(LSPR)peak could be effectively adjusted between 490 nm and 713 nm by decreasing the cavity size of the Au-Ag hollow nanoparticles from 35 nm to 20 nm.The plasmon-enhanced photocatalytic H2 evolution of alloy nanoparticles with different cavity sizes was investigated.Compared with pure P25(TiO2),intact and thin-shelled Au-Ag hollow nanoparticles(HNPs)-supported photocatalyst exhibited an increase in the photocatalytic H2 evolution rate from 0.48μmol h^−1 to 4μmol h^−1 under full-spectrum irradiation.This improved photocatalytic performance was likely due to the plasmon-induced electromagnetic field effect,which caused strong photogenerated charge separation,rather than the generation of hot electrons.
基金Project supported by the Initial Research Fund of Shihezi University,China (Grant Nos. RCZX200742 and RCZX200743)
文摘Using the reductive perturbation method,we investigate the small amplitude nonlinear acoustic wave in a collisional self-gravitating dusty plasma.The result shows that the small amplitude dust acoustic wave can be expressed by a modified Korteweg-de Vries equation,and the nonlinear wave is instable because of the collisions between the neutral gas molecules and the charged particles.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.21403144,11464038,11134005,and 51472113)the National Key Project for Basic Research of China(Grant Nos.2013CB922103 and 2015CB921203)。
文摘Single molecule magnets(SMMs) with large magnetic anisotropy energy(MAE) have great potential applications in magnetic recording.Using the first-principles calculations,we investigate the MAE of 5 d transition metal-porphyrin-based SMMs by using the PBE and PBE+U with different U values,respectively.The results indicate that W-P,Re-P,Os-P,and Ir-P possess the considerably large MAE among 5 d TM-P SMMs.Furthermore,the MAE of 5 d TM-P can be facilely manipulated by tensile strain.The reduction of the absolute value of MAE for Ir-P molecule caused by tensile strain makes it easier to implement the writing operation.The decreasing of the occupation number of minority-spin channels of Ir-d_(x^(2)-y^(2)) orbital leads the MAE to decrease when the tensile strain increases.
基金supported by the Natural Science Foundation of China(No.51962032)the program for Strong Youth Technology Leading Talents in Bingtuan Technological Innovation Talents(No.2023CB008-11)+1 种基金the Youth Innovative Top Talents Fund,Shihezi University(No.CXBJ202203)Youth Science and Technology Innovation Leading Talent Fund,Bashi Shihezi(No.2023RC02).
文摘Dendrites growth,chemical corrosion,and hydrogen evolution reaction(HER)on zinc anodes are the main barriers for the development of aqueous zinc-ion batteries(AZIBs).Constructing interfacial protec-tive layer is an effective way to alleviate the side reactions on the anodes.Herein,Cu/Ti_(3)C_(2)Cl_(2)MXene(CMX)with high zincophilic and hydrophobic property is prepared by the lewis molten salts etching method,and the CMX interface protection layer is constructed by a simple spin coating.The CMX coat-ing layer can provide abundant nucleation sites and uniformize the charge distribution through the zin-cophilic Ti_(3)C_(2)Cl_(2)MXene matrix,leading to homogenous Zn deposition.In addition,the hydrophobic coat-ing contained anti-corrosive Cu nanoparticles can prevent the Zn anode from the electrolyte,beneficial for suppressing the chemical corrosion and HER.Therefore,the stable and reversible Zn plating/stripping is achieved for the Zn anode coated by the CMX,which exhibits the lifespan of over 1400 h at 0.5 mA cm^(−2),and even can steadily run for 700 h with 65 mV at 10 mA cm^(−2).Furthermore,CMX@Zn shows a high coulombic efficiency of over 100%for 3800 cycles,which indicates that the CMX@Zn electrode has excellent stability and reversibility of Zn stripping/plating.The full batteries assembled with ZnCoMnO/C(ZCM)cathodes also exhibits higher capacity(450.6 mAh g^(−1)at 0.1 A g^(−1))and cycle stability(capacity retention of 70%after 1500 cycles).This work enhanced the lifespan of AZIBs and broaden the research of multifunctional coating layer to other secondary batteries based on metal anodes.
基金financially supported by Gansu Provincial Natural Science Foundation of China(Nos.17JR5RA198,2020HZ-2)the Cooperation project of Gansu Academy of Sciences(No.2020HZ-2)+1 种基金the Fundamental Research Funds for the Central Universities(Nos.lzujbky-2018-119,lzujbky-2018-ct08,lzujbky-2019-it23)the Key Areas Scientific and Technological Research Projects in Xinjiang Production and Construction Corps(No.2018AB004)。
文摘For zinc air batteries,a non-noble metal-based electrocatalyst with a high performance and stability in oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)is imperative in application.Herein,a catalyst based on FeCo-N encapsuled in nitrogen-doped carbon nanotubes has been prepared,which provides an implementable method to design controlled structures with excellent bifunction al electrocatalytic activities.By adjusting the molar ratio of two metals,the synthesized FeCo-N-C catalyst delivers a competitive ORR and OER performance compared with commercial Pt/C and IrO_(2),performing a low overvoltage gap between ORR(E_(1/2))and OER(E_(j=10))of 0.8 V.Moreover,as a promising cathode in zinc air battery,the FeCo-N-C catalyst possesses an affirmative stability of over 100 h and large power density(129 mW·cm^(-2)).This work demonstrates that FeCo-N-C is one of the most promising catalysts for zinc air batteries and provides a possibility for exploration of batteries with high stability by adjusting the molar ratio of metals in the catalysts.
基金the National Natural Science Foundation of China(Grant Nos.51662036 and 61704114)the Open Foundation of Engineering Research Center of Materials-Oriented Chemical Engineering of Xinjiang Bintuan(2016BTRC005)the Graduate Student Scientific Research Innovation Projects in Xinjiang Autonomous Region,China(XJGRI2017046).
文摘ZnO nanocone arrays(NCAs)decorated with black TiO2 nanoparticles(BTiO2 NPs)were uniformly anchored on the surface of carbon cloth(CC)directly by a simply electrochemical deposition method.Thus a novel B-TiO2 NPs/ZnO NCAs-CC hierarchical heterostructure was formed.It displayed superior performance and achieved a higher photocurrent over 0.4 mA·cm^-2 before the onset of the dark current,attributed to the separation of the photogenerated electron-hole pair.Based on the B-TiO2 NPs/ZnO NCAs-CC heterostructure,the catalyst was fabricated for promoting the separation of charge carriers.Moreover,the introduction of Ti^3+ and oxygen vacancies on the surface of TiO2 NPs expanded the absorption band edge and enhanced the electrical conductivity as well as the charge transportation on the catalytic surface.It indicates that the B-TiO2 NPs/ZnO NCAs-CC composite is beneficial to the improvement of the photoelectrochemical(PEC)activity.
基金supported by the National Natural Science Foundation of China(51362026)the Technological Innovation Youth Training Project of Xinjiang Uyghur Autonomous Region of China(QN2015YX004)+1 种基金Qun Jing would like to acknowledge the support from the Foundation for High-level Talents in Shihezi University(RCZX201511)the Applied Basic Research Foundation of Science and Technology in Shihezi University(2015ZRKXYQ07)