Utilizing the acoustic emission(AE) technique, an experimental investigation into the damage evolution for steel strand under axial tension was described. The damage evolution model for steel stand relating the damage...Utilizing the acoustic emission(AE) technique, an experimental investigation into the damage evolution for steel strand under axial tension was described. The damage evolution model for steel stand relating the damage evolution to acoustic emission parameters was proposed by incorporating the AE rate process theory. The AE monitoring results indicate that damages occur in both elastic and plastic phases of steel strand. In elastic phase, AE signals are mainly sent out from the micro damage due to the surface friction among the wires of steel strand, while in plastic phase, AE signals emitted from the plastic deformation of wires. In addition, the AE cumulative parameters curves closely resemble the loading curve. The AE cumulative parameters curves can well describe the damage evolution process including the damage occurrence and damage development for steel strands. It is concluded that the AE technique is an effective and useful nondestructive technique for evaluating the damage characteristics of steel strand.展开更多
Despite almost half a century of research for theory of mind, its evolutionary origin is largely unknown. This paper proposes that the evolutionary origin of theory of mind starts from the beginning of the human evolu...Despite almost half a century of research for theory of mind, its evolutionary origin is largely unknown. This paper proposes that the evolutionary origin of theory of mind starts from the beginning of the human evolution to form hominins through bipedalism and the mixed habitat. The feet of the early hominins were still adapted for grasping trees rather than walking for long distances and running fast on the ground. The early hominins lived in the mixed habitat of grassy woodland with patches of denser forest, and freshwater springs. The difficulty of walking in the mixed habitat leads to division of labor for the home specialist group (small children, old people, and mothers with small children, and pregnant women) in the safe forest area and the exploration specialist group (young people without the care of small children) in the dangerous open area. The different tasks, attitudes, and mentalities in different specialist groups produce theory of mind as the ability to attribute different mental states to different specialist groups. (Uniformity of mind instead of theory of mind is for generalists without division of labor). The early Homo species with the open habitat developed theory of mind for hunter specialist group and gatherer specialist group. The middle Homo species with complex stone tools developed theory of mind for the cooperative specialist groups in the large production of complex stone tools. The late Homo species with complex social interaction developed theory of mind for mind reading to enhance cooperation and to detect cheaters in complex social interaction. For religion, the unusually harsh Upper Paleolithic Period developed theory of mind for imaginary specialists in terms of supernatural power, guidance, and comfort. Therefore, the three general types of theory of mind are for specialists in division of labor, mind reading in complex social interaction, and imaginary specialists in imaginary division of labor under harsh conditions. Self-awareness in the mirror self-recognition test is also explained.展开更多
Density functional theory(DFT)is used to calculate the most stable structures of Zr_(n)(n=2-5)clusters as well as the adsorption energy values of Zr_(n)(n=2-5)clusters after adsorbing single water molecule.The results...Density functional theory(DFT)is used to calculate the most stable structures of Zr_(n)(n=2-5)clusters as well as the adsorption energy values of Zr_(n)(n=2-5)clusters after adsorbing single water molecule.The results reveal that there is a significant linear relationship between the adsorption energy values and the energy gaps of the Zr_(n)(n=2-5)clusters.Furthermore,the calculations of the reaction paths between Zr_(n)(n=2-5)and single water molecule show that water molecule can react with Zr_(n)(n=2-5)clusters to dissociate,producing hydrogen,and O atoms mix with the clusters to generate Zr_(n)O(n=2-5),all of which are exothermic reactions.According to the released energy,the Zr4 cluster is the most efficient in Zr_(n)(n=2-5)clusters reacting with single water molecule.The natural population analysis(NPA)and density of states(DOS)demonstrate the production of hydrogen and orbital properties in different energy ranges,respectively,jointly forecasting that Zr_(n)O(n=2-5)will probably continue to react with more water molecules.Our findings contribute to better understanding of Zr's chemical reactivity,which can conduce to the development of effective Zr-based catalysts and hydrogen-production methods.展开更多
It is generally cousidered that the mantle creep-flow eurtent is the most important internal cause for erustobody evolution. In fact, the Cause, mantle creep-now current takes place just beneath erustobody. Aeeording ...It is generally cousidered that the mantle creep-flow eurtent is the most important internal cause for erustobody evolution. In fact, the Cause, mantle creep-now current takes place just beneath erustobody. Aeeording to the principle that internal causes of a tning determine its development and evolution, a special attetion should be paid to the basic causea of crustobody evolution. Vnder the guidance of the unbalanced self-organization theory, the authors elueidate that the crustobody system is a far-away thermal balaneed system and an open system, and thete are nonlinear interactions between the essentials, positive feedbacks and frequent fluetuation in the erustobody system. Finally, the following conelusions are drawn: the nonlinear interactions in the erustobody system are the basic formation (main internal cause) for erustobody evolution ; Substance and energy gained from surroundings are the basic conditions (main external cause) of crustobody evolution;and the fluctuations theide the erustobody system are the direct induetive cause of its evolution.展开更多
The purpose of the paper civilization is to provide a is to show violence as the integral property of any live being. One of the aims of controlled portion of violence to the community members. If the portions are too...The purpose of the paper civilization is to provide a is to show violence as the integral property of any live being. One of the aims of controlled portion of violence to the community members. If the portions are too small then uncontrolled violence appears in different forms of criminality and self-destruction. In countries without virtual violence the terrorism and "suicide" bombers are born. For the male the aim of violence is a feeling of victory. In the nature only the winner has the right to reproduction. In a civilized society each male has the right to reproduction and the necessity to feel himself as a winner. Survival means right for reproduction. Civilization has turned the bite between men into a kiss between men (men winner) and women (men defeated), the kick between men--into a caress between men (men winner) and women (men defeated) and, finally, the violence between men into love/eros between men (men winner) and women (men vanquished) and violence between men into homosexuality/eros between men winner and men vanquished. In the civilization, the male is winner and the female simulates the defeated male, homo or animals. We can define eros as a substitute of violence in civilization like the metamorphose of violence.展开更多
The problem of human language, arithmetic, and art was studied in the context of the definition "civilization" on the basis of Darwin's theory. The author defines civilization as "survival of the weak". The autho...The problem of human language, arithmetic, and art was studied in the context of the definition "civilization" on the basis of Darwin's theory. The author defines civilization as "survival of the weak". The author supposes that language and art were invented by the men to describe their heroic deeds for the women in order to be selected by them for reproduction. In other words, language and art became a selection criterions together with beauty and presents. Finally, the author defines language and art.展开更多
This paper modifies the Farnes’ unifying theory of dark energy and dark matter which are negative-mass, created continuously from the negative-mass universe in the positive-negative mass universe pair. The first modi...This paper modifies the Farnes’ unifying theory of dark energy and dark matter which are negative-mass, created continuously from the negative-mass universe in the positive-negative mass universe pair. The first modification explains that observed dark energy is 68.6%, greater than 50% for the symmetrical positive-negative mass universe pair. This paper starts with the proposed positive-negative-mass 11D universe pair (without kinetic energy) which is transformed into the positive-negative mass 10D universe pair and the external dual gravities as in the Randall-Sundrum model, resulting in the four equal and separate universes consisting of the positive-mass 10D universe, the positive-mass massive external gravity, the negative-mass 10D universe and the negative-mass massive external gravity. The positive-mass 10D universe is transformed into 4D universe (home universe) with kinetic energy through the inflation and the Big Bang to create positive-mass dark matter which is five times of positive-mass baryonic matter. The other three universes without kinetic energy oscillate between 10D and 10D through 4D, resulting in the hidden universes when D > 4 and dark energy when D = 4, which is created continuously to our 4D home universe with the maximum dark energy = 3/4 = 75%. In the second modification to explain dark matter in the CMB, dark matter initially is not repulsive. The condensed baryonic gas at the critical surface density induces dark matter repulsive force to transform dark matter in the region into repulsive dark matter repulsing one another. The calculated percentages of dark energy, dark matter, and baryonic matter are 68.6 (as an input from the observation), 26 and 5.2, respectively, in agreement with observed 68.6, 26.5 and 4.9, respectively, and dark energy started in 4.33 billion years ago in agreement with the observed 4.71 <span style="white-space:nowrap;">±</span> 0.98 billion years ago. In conclusion, the modified Farnes’ unifying theory reinterprets the Farnes’ equations, and is a unifying theory of dark energy, dark matter, and baryonic matter in the positive-negative mass universe pair. The unifying theory explains protogalaxy and galaxy evolutions in agreement with the observations.展开更多
Through rock mechanics test, similar simulation experiment, borehole photographic observation of rock fissure, numerical simulation calculation of plastic zone distribution and deformation monitoring of rock mass duri...Through rock mechanics test, similar simulation experiment, borehole photographic observation of rock fissure, numerical simulation calculation of plastic zone distribution and deformation monitoring of rock mass during undersea mining, the fractal evolution mechanisms of rock fracture in undersea metallic deposits of Sanshandao Gold Mine were studied by fractal theory. The experimental researches on granite mechanics test in undersea deposit indicate that with the increase of load, the granite deformation energy and the fractal dimension of acoustic emission(FDAE) increase gradually. However, after reaching the peak stress of specimen, the fractal dimensions of acoustic emission(FDAEs) decrease and the granite specimen fails. Therefore, the fractal dimension evolution of rock failure can be divided into four stages, which are fissure inoculation stage, fissure growth stage, fissure expansion stage and fracture instability stage, respectively. By calculating and analyzing the damage photographs of rock specimens in Sanshandao Gold Mine, the fractal dimension of rock fissure is 1.4514, which is close to the average value of FDAE during granite destruction, i.e., 1.4693. Similar simulation experiments of undersea mining show that with the excavation proceeding, the FDAE in rock stratum increases gradually, and when the thickness of the isolation roof is less than 40 m, the FDAE begins to decrease, and meanwhile the sign of water inrush emerges. The numerical simulation researches on the plastic zone distribution of undersea mining in Sanshandao Gold Mine indicate that the fractal dimension of plastic zone(FDPZ) where the failure characteristics occur is 1.4598, close to the result of similar simulation experiment of 1.4364, which shows the sign of water inrush. Meanwhile, the thickness of the isolation roof for undersea mining should be more than 40 m, which is consistent with the results of similar simulation experiment. In Sanshandao Gold Mine, the rock fissures in undersea mining were observed by borehole photography and the rock mass deformation was monitored by multi-point displacement meters, and at the same time the fractal dimensions of strata borehole fissure distribution and energy release ratio(ERR) of rock mass were calculated by fractal principle, which are 1.2328 and 1.2685, respectively. The results demonstrate that rock deformation and fissure propagation are both in the second stage of fissure growth, and have not reached the fourth stage of fracture instability. Therefore, the conclusion can be obtained that the undersea mining in Sanshandao Gold Mine is safe at present.展开更多
The ferrocene(Fc)-based metal-organic frameworks(MOFs)are regarded as compelling platforms for the construction of efficient and robust oxygen evolution reaction(OER)electrocatalysts due to their superior conductivity...The ferrocene(Fc)-based metal-organic frameworks(MOFs)are regarded as compelling platforms for the construction of efficient and robust oxygen evolution reaction(OER)electrocatalysts due to their superior conductivity and flexible electronic structure.Herein,density functional theory simulations were addressed to predict the electronic structure regulations of CoFc-MOF by nickel doping,which demonstrated that the well-proposed CoNiFc-MOFs delivered a small energy barrier,promoted conductivity,and well-regulated d-band center.Inspired by these,a series of sea-urchin-like CoNiFc-MOFs were successfully synthesized via a facile solvothermal method.Moreover,the synchrotron X-ray and X-ray photoelectron spectroscopy measurements manifested that the introduction of nickel could tailor the electronic structure of the catalyst and induce the directional transfer of electrons,thus optimizing the rate-determining step of^(*)O→^(*)OOH during the OER process and yielding decent overpotentials of 209 and 252 mV at 10 and 200 mA cm^(−2),respectively,with a small Tafel slope of 39 mV dec^(−1).This work presents a new paradigm for developing highly efficient and durable MOF-based electrocatalysts for OER.展开更多
In this study,we investigated the hydrogen evolution reaction(HER)on the(101)facet of pristine and W-doped CoP using the density functional theory.Two types of Co atoms are identified on the catalyst surface:the Co at...In this study,we investigated the hydrogen evolution reaction(HER)on the(101)facet of pristine and W-doped CoP using the density functional theory.Two types of Co atoms are identified on the catalyst surface:the Co atoms that present the higher d band center are marked as valid sites,whereas the others are marked as invalid sites owing to their weaker H adsorption ability.It is further revealed that W-doping can decrease the d band center of the surface Co atoms,which is beneficial for the HER;however the exposure to W weakens the desorption of H.To address the strong adsorption effect of W,the doping sites and dopant content are analyzed,and the results indicate that 8.4 wt%W doping at the invalid surface Co sites is preferred;moreover,the optimal W content increases to 16.8 wt%when W is inserted into the subsurface.The effect of W doping is weakened when the doping site is far away from the surface.展开更多
Electrocatalytic oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER)in acidic media are vital for the applications of renewable energy electrolyzers.However,the low mass activity of noble Pt urgently ne...Electrocatalytic oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER)in acidic media are vital for the applications of renewable energy electrolyzers.However,the low mass activity of noble Pt urgently needs to be improved due to the strong binding energetics of oxygen species(*O)with Pt sites.Here we report fine PtxSr alloy(-2 nm)supported on N-doped carb on(NC)pyrolyzing from ZIF-8 as bifunctional electrocatalysts toward ORR and HER in acidic media.The representative Pt_(2)Sr/NC exhibits an onset potential of 0.94 V vs.RHE and half-wave potential of 0.84 V toward ORR,and a low over-potential of 27 mV(10 mA cm^(-2))toward HER,respectively.Significantly,the mass activities of Pt_(2)Sr/NC are 6.2 and 2.6 times higher than that of Pt/C toward ORR(at 0.9 V)and HER(at-30 mV),respectively.Simultaneously,Pt_(2)Sr/NC possesses a retention rate of 90.97%toward acidic ORR after 35000 s of continuous operation.Through density functional theory(DFT)calculations and X-ray photoelectron spectroscopy analysis,the incorporation of Sr into Pt forming Pt_(2)Sr alloy redistributes the electronic structures of Pt-Pt bonds,changing the rate-determining step for the ORR on Pt sites from the formation of*OH from*O to the generation of*OOH along with decreasing the energy barrier,which is also confirmed by the downshift of d band center.Meanwhile,the downshift of d band center also leads to the optimization of the adsorption energy(H*)with Pt,significantly improving Pt_(2)Sr/NC toward HER.展开更多
Nickel molybdate(NiMoO_(4))attracts superior hydrogen desorption behavior but noticeably poor for efficiently driving the hydrogen evolution reaction(HER)in alkaline media due to the sluggish water dissociation step.H...Nickel molybdate(NiMoO_(4))attracts superior hydrogen desorption behavior but noticeably poor for efficiently driving the hydrogen evolution reaction(HER)in alkaline media due to the sluggish water dissociation step.Herein,we successfully accelerate the water dissociation kinetics of NiMoO_(4)for prominent HER catalytic properties via simultaneous in situ interfacial engineering with molybdenum dioxide(MoO_(2))and doping with phosphorus(P).The as-synthesized P-doped NiMoO_(4)/MoO_(2)heterostructure nanorods exhibit outstanding HER performance with an extraordinary low overpotential of-23 m V at a current density of 10 m A cm^(-2),which is highly comparable to the performance of the state-of-art Pt/C coated on nickel foam(NF)catalyst.The density functional theory(DFT)analysis reveals the enhanced performance is attributed to the formation of MoO_(2)during the in situ epitaxial growth that substantially reduces the energy barrier of the Volmer pathway,and the introduction of P that provides efficient hydrogen desorption of Ni MoO_(2).This present work creates valuable insight into the utilization of interfacial and doping systems for hydrogen evolution catalysis and beyond.展开更多
Oxygen evolution reaction(OER)is the dominant step for plenty of energy conversion and storage technologies.However,the OER suffers from sluggish kinetics and high overpotential due to its complex 4‐electron/proton t...Oxygen evolution reaction(OER)is the dominant step for plenty of energy conversion and storage technologies.However,the OER suffers from sluggish kinetics and high overpotential due to its complex 4‐electron/proton transfer mechanism.Thus,developing efficient electrocatalysts is particularly urgent to accelerate OER catalysis but still remains a great challenge.Herein,we have synthesized the novel cobalt molybdate nanoflakes(CoMoO_(4)‐O_(v)‐n@GF)with adjustable oxygen vacancies contents by in situ constructing CoMoO_(4) nanoflakes on graphite felt(GF)and annealing treatment under the reduction atmosphere.The best‐performing CoMoO_(4)‐O_(v)‐2@GF with optimal oxygen vacancies content shows splendid electrocatalytic performance with the low overpotential(296 mV at 10 mA cm^(‒2))and also small Tafel slope(62.4 mV dec^(‒1))in alkaline solution,which are comparable to those of the RuO_(2)@GF.The experimental and the density functional theory calculations results reveal that the construction of optimal oxygen vacancies in CoMoO_(4) can expose more active sites,narrow the band‐gap to increase the electrical conductivity,and modulate the free energy of the OER‐related intermediates to accelerate OER kinetics,thus improving its intrinsic activity.展开更多
Rational design of high-performance electrocatalysts for hydrogen evolution reaction(HER)is vital for future renewable energy systems.The incorporation of foreign metal ions into catalysts can be an effective approach...Rational design of high-performance electrocatalysts for hydrogen evolution reaction(HER)is vital for future renewable energy systems.The incorporation of foreign metal ions into catalysts can be an effective approach to optimize its performance.However,there is a lack of systematic theoretical studies to reveal the quantitative relationships at the electronic level.Here,we develop a multi-level screening methodology to search for highly stable and active dopants for CoP catalysts.The density functional theory(DFT)calculations and symbolic regression(SR)were performed to investigate the relationship between the adsorption free energy(ΔG_(H^(*)))and 10 electronic parameters.The mathematic formulas derived from SR indicate that the difference of work function(ΔΦ)between doped metal and the acceptor plays the most important role in regulatingΔG_(H^(*)),followed by the d-band center(d-BC)of doped system.The descriptor of HER can be expressed asΔG_(H^(*))=1.59×√|0.188ΔΦ+d BC+0.120|1/2-0.166 with a high determination coefficient(R^(2)=0.807).Consistent with the theoretical prediction,experimental results show that the Al-CoP delivers superior electrocatalytic HER activity with a low overpotential of75 m V to drive a current density of 10 mA cm^(-2),while the overpotentials for undoped CoP,Mo-CoP,and V-CoP are 206,134,and 83 m V,respectively.The current work proves that theΔΦis the most significant regulatory parameter ofΔG_(H^(*))for ion-doped electrocatalysts.This finding can drive the discovery of high-performance ion-doped electrocatalysts,which is crucial for electrocatalytic water splitting.展开更多
“= everything flows”, Eraclitus, (Ephesus, 535-475 B.C.). If really in Nature everything changes and progresses, then at least two questions arise: 1) how can be these changes entropic but nonetheless somehow predic...“= everything flows”, Eraclitus, (Ephesus, 535-475 B.C.). If really in Nature everything changes and progresses, then at least two questions arise: 1) how can be these changes entropic but nonetheless somehow predictable without risk of oxymoronic behavior;2) how can Science conform itself to follow this requirement of the Nature. To attempt an answer to these questions, the present paper introduces an ab initio theoretical model aimed to show that physical information is actually nothing else but straightforward quantum and relativistic implication of the concept of evolution.展开更多
In this paper,we report,for the first time,on the electrochemical catalytic activity of 2D titanium carbonitride MXene for hydrogen evolution reaction(HER).According to our study,2D titanium carbonitride exhibited muc...In this paper,we report,for the first time,on the electrochemical catalytic activity of 2D titanium carbonitride MXene for hydrogen evolution reaction(HER).According to our study,2D titanium carbonitride exhibited much higher electrocatalytic activity than its carbide analogues,achieving an onset overpotential of 53 mV and Tafel slope of 86 mV dec^(-1),superior to the titanium carbide with onset overpotential of 649 mV and Tafel slope of 303 mV dec^(-1).The obtained onset overpotential for 2D titanium carbonitride is lower than those of all the reported transition metal carbides MXene catalysts without additives,so far.Density functional theory calculations were conducted to further understand the electrochemical performance.The calculation results show that a greater number of occupied states are active for Ti_(3)CNO_(2),revealing free energy for the adsorption of atomic hydrogen closer to 0 than that of Ti_(3)C_(2)O_(2).Both experimental and calculation studies demonstrate the excellent electrocatalytic behavior of titanium carbonitride.The investigation of 2D titanium carbonitride opens up a promising paradigm for the conscious design of high-performance non-precious metal catalyst for hydrogen generation.展开更多
In the semiconductor-based photocatalysts for overall water splitting, loading proper cocatalysts play a crucial role in enhancing the photocatalytic activity. In this work, we have chosen Ni_n/α-Ga_2O_3 as a model a...In the semiconductor-based photocatalysts for overall water splitting, loading proper cocatalysts play a crucial role in enhancing the photocatalytic activity. In this work, we have chosen Ni_n/α-Ga_2O_3 as a model and provided detailed density functional theory calculations to investigate the function of cocatalysts in hydrogen evolution reaction(HER). We have studied the formation and stability of Ni_n(n = 1–4) cluster on two stable surfaces of α-Ga_2O_3(001) and(012). In a Ni_n/α-Ga_2O_3 system, as the Ni 3d states well overlap with O and Ga states, the excited electrons transferred from Ga to Ni may participate in HER. We theoretically predict that introduction of Nincluster on(012) surface can elevate the Fermi level toward the conduction band, which is favorable for the occurrence of HER. Electrochemical computations are used to explore the mechanism of HER. It is found that, in most of Ni_n/α-Ga_2O_3 systems, the active sites of HER are on Ni_n clusters. Loading Ni_n clusters not only importantly reduces the Gibbs free energy of HER but also improves the reaction activity of surface O and Ga sites in HER. Our calculations reasonably explain the experimental observation on significant enhancement of activity for generating hydrogen after loading nickel oxide cocatalysts.展开更多
The paper proposes that the four-component structure of political order consists of state, imagination, rule, and accountability whose mental origins are the social brain, theory of mind, the rational brain, and the e...The paper proposes that the four-component structure of political order consists of state, imagination, rule, and accountability whose mental origins are the social brain, theory of mind, the rational brain, and the empirical brain, respectively. The rational brain and the empirical brain are from the thinking brain. This paper posits that in the evolution of political order, the main function of political order is to pacify changed social structure derived from technological revolution. Therefore, the four technological revolutions (the Upper Paleolithic, Agricultural-Bronze, Iron, and Industrial Revolutions) produce the four changed social structures (linked bands, tribe, mega empire, and modern nation, respectively) whose internal conflicts are pacified by the four political revolutions (the imaginative, hierarchical, thinking, bottom-up political revolutions, respectively) to form the four politics (the imaginative egalitarianism, decentralized hierarchical tribalism, centralized top-down thinking, and multilateral bottom-up thinking politics, respectively). In the competitive West originated from Greece and Middle East, the rule of law is the rational rule of competition among competitors, and the accountability of election is the empirical accountability of competition among competitors. In the cooperative East originated from India and China, the rule of relation is the rational rule of cooperation among kin-friends, and the accountability of professional qualification is the empirical accountability of cooperation among kin-friends. For political order, the two viable politics are competitive liberal democracy based on liberty and cooperative well-off democracy (well-off socialism) based on wellbeing. The direction of political order is middle democracy between liberal democracy and well-off democracy based on the multilateral bottom-up thinking politics.展开更多
A common problem in molecular comparative geno- mics is the identification of genes that are under positive, adaptive selection [1]. Such genes are likely to be crucial for speciation, species differentiation, and fun...A common problem in molecular comparative geno- mics is the identification of genes that are under positive, adaptive selection [1]. Such genes are likely to be crucial for speciation, species differentiation, and func- tional specialization. However, discerning the difference between positive selection and relaxation of func- tional constraint can be difficult using current methods. Both processes generally increase the rate of ami- no acid change relative to synonymous changes within coding regions, and unless the amino acid rate is over- whelmingly high across an entire gene, the signature of positive selection can be obscured [2]. Some methodologies do not explicitly determine the difference be- tween a relaxation of functional constraint and positive selection, leaving researchers to determine via other means whether the trajectory of a gene has been specialization or creation of a new function, or removal from the genome via a process of degeneration.展开更多
基金Projects(51308073,51378081)supported by the National Natural Science Foundation of ChinaProject(20124316120002)supported by PhD Programs Foundation of Ministry of Education of China+1 种基金Project(12KB02)supported by the Key Laboratory for Safety Control of Bridge Engineering of Ministry of Education of ChinaProject(14JJ3087)supported by the Science Foundation of Hunan Province,China
文摘Utilizing the acoustic emission(AE) technique, an experimental investigation into the damage evolution for steel strand under axial tension was described. The damage evolution model for steel stand relating the damage evolution to acoustic emission parameters was proposed by incorporating the AE rate process theory. The AE monitoring results indicate that damages occur in both elastic and plastic phases of steel strand. In elastic phase, AE signals are mainly sent out from the micro damage due to the surface friction among the wires of steel strand, while in plastic phase, AE signals emitted from the plastic deformation of wires. In addition, the AE cumulative parameters curves closely resemble the loading curve. The AE cumulative parameters curves can well describe the damage evolution process including the damage occurrence and damage development for steel strands. It is concluded that the AE technique is an effective and useful nondestructive technique for evaluating the damage characteristics of steel strand.
文摘Despite almost half a century of research for theory of mind, its evolutionary origin is largely unknown. This paper proposes that the evolutionary origin of theory of mind starts from the beginning of the human evolution to form hominins through bipedalism and the mixed habitat. The feet of the early hominins were still adapted for grasping trees rather than walking for long distances and running fast on the ground. The early hominins lived in the mixed habitat of grassy woodland with patches of denser forest, and freshwater springs. The difficulty of walking in the mixed habitat leads to division of labor for the home specialist group (small children, old people, and mothers with small children, and pregnant women) in the safe forest area and the exploration specialist group (young people without the care of small children) in the dangerous open area. The different tasks, attitudes, and mentalities in different specialist groups produce theory of mind as the ability to attribute different mental states to different specialist groups. (Uniformity of mind instead of theory of mind is for generalists without division of labor). The early Homo species with the open habitat developed theory of mind for hunter specialist group and gatherer specialist group. The middle Homo species with complex stone tools developed theory of mind for the cooperative specialist groups in the large production of complex stone tools. The late Homo species with complex social interaction developed theory of mind for mind reading to enhance cooperation and to detect cheaters in complex social interaction. For religion, the unusually harsh Upper Paleolithic Period developed theory of mind for imaginary specialists in terms of supernatural power, guidance, and comfort. Therefore, the three general types of theory of mind are for specialists in division of labor, mind reading in complex social interaction, and imaginary specialists in imaginary division of labor under harsh conditions. Self-awareness in the mirror self-recognition test is also explained.
基金Project supported by the Open Research Fund of Computational Physics Key Laboratory of Sichuan Province,Yibin University,China(Grant No.YBXYJSWL-ZD-2020-005)the Student’s Platform for Innovation and Entrepreneurship Training Program,China(Grant No.S202110616084)。
文摘Density functional theory(DFT)is used to calculate the most stable structures of Zr_(n)(n=2-5)clusters as well as the adsorption energy values of Zr_(n)(n=2-5)clusters after adsorbing single water molecule.The results reveal that there is a significant linear relationship between the adsorption energy values and the energy gaps of the Zr_(n)(n=2-5)clusters.Furthermore,the calculations of the reaction paths between Zr_(n)(n=2-5)and single water molecule show that water molecule can react with Zr_(n)(n=2-5)clusters to dissociate,producing hydrogen,and O atoms mix with the clusters to generate Zr_(n)O(n=2-5),all of which are exothermic reactions.According to the released energy,the Zr4 cluster is the most efficient in Zr_(n)(n=2-5)clusters reacting with single water molecule.The natural population analysis(NPA)and density of states(DOS)demonstrate the production of hydrogen and orbital properties in different energy ranges,respectively,jointly forecasting that Zr_(n)O(n=2-5)will probably continue to react with more water molecules.Our findings contribute to better understanding of Zr's chemical reactivity,which can conduce to the development of effective Zr-based catalysts and hydrogen-production methods.
文摘It is generally cousidered that the mantle creep-flow eurtent is the most important internal cause for erustobody evolution. In fact, the Cause, mantle creep-now current takes place just beneath erustobody. Aeeording to the principle that internal causes of a tning determine its development and evolution, a special attetion should be paid to the basic causea of crustobody evolution. Vnder the guidance of the unbalanced self-organization theory, the authors elueidate that the crustobody system is a far-away thermal balaneed system and an open system, and thete are nonlinear interactions between the essentials, positive feedbacks and frequent fluetuation in the erustobody system. Finally, the following conelusions are drawn: the nonlinear interactions in the erustobody system are the basic formation (main internal cause) for erustobody evolution ; Substance and energy gained from surroundings are the basic conditions (main external cause) of crustobody evolution;and the fluctuations theide the erustobody system are the direct induetive cause of its evolution.
文摘The purpose of the paper civilization is to provide a is to show violence as the integral property of any live being. One of the aims of controlled portion of violence to the community members. If the portions are too small then uncontrolled violence appears in different forms of criminality and self-destruction. In countries without virtual violence the terrorism and "suicide" bombers are born. For the male the aim of violence is a feeling of victory. In the nature only the winner has the right to reproduction. In a civilized society each male has the right to reproduction and the necessity to feel himself as a winner. Survival means right for reproduction. Civilization has turned the bite between men into a kiss between men (men winner) and women (men defeated), the kick between men--into a caress between men (men winner) and women (men defeated) and, finally, the violence between men into love/eros between men (men winner) and women (men vanquished) and violence between men into homosexuality/eros between men winner and men vanquished. In the civilization, the male is winner and the female simulates the defeated male, homo or animals. We can define eros as a substitute of violence in civilization like the metamorphose of violence.
文摘The problem of human language, arithmetic, and art was studied in the context of the definition "civilization" on the basis of Darwin's theory. The author defines civilization as "survival of the weak". The author supposes that language and art were invented by the men to describe their heroic deeds for the women in order to be selected by them for reproduction. In other words, language and art became a selection criterions together with beauty and presents. Finally, the author defines language and art.
文摘This paper modifies the Farnes’ unifying theory of dark energy and dark matter which are negative-mass, created continuously from the negative-mass universe in the positive-negative mass universe pair. The first modification explains that observed dark energy is 68.6%, greater than 50% for the symmetrical positive-negative mass universe pair. This paper starts with the proposed positive-negative-mass 11D universe pair (without kinetic energy) which is transformed into the positive-negative mass 10D universe pair and the external dual gravities as in the Randall-Sundrum model, resulting in the four equal and separate universes consisting of the positive-mass 10D universe, the positive-mass massive external gravity, the negative-mass 10D universe and the negative-mass massive external gravity. The positive-mass 10D universe is transformed into 4D universe (home universe) with kinetic energy through the inflation and the Big Bang to create positive-mass dark matter which is five times of positive-mass baryonic matter. The other three universes without kinetic energy oscillate between 10D and 10D through 4D, resulting in the hidden universes when D > 4 and dark energy when D = 4, which is created continuously to our 4D home universe with the maximum dark energy = 3/4 = 75%. In the second modification to explain dark matter in the CMB, dark matter initially is not repulsive. The condensed baryonic gas at the critical surface density induces dark matter repulsive force to transform dark matter in the region into repulsive dark matter repulsing one another. The calculated percentages of dark energy, dark matter, and baryonic matter are 68.6 (as an input from the observation), 26 and 5.2, respectively, in agreement with observed 68.6, 26.5 and 4.9, respectively, and dark energy started in 4.33 billion years ago in agreement with the observed 4.71 <span style="white-space:nowrap;">±</span> 0.98 billion years ago. In conclusion, the modified Farnes’ unifying theory reinterprets the Farnes’ equations, and is a unifying theory of dark energy, dark matter, and baryonic matter in the positive-negative mass universe pair. The unifying theory explains protogalaxy and galaxy evolutions in agreement with the observations.
基金Project(2019sdzy05)supported by the Major Scientific and Technological Innovation Project of Shandong Province,ChinaProjects(51674288,51974359)supported by the National Natural Science Foundation of China。
文摘Through rock mechanics test, similar simulation experiment, borehole photographic observation of rock fissure, numerical simulation calculation of plastic zone distribution and deformation monitoring of rock mass during undersea mining, the fractal evolution mechanisms of rock fracture in undersea metallic deposits of Sanshandao Gold Mine were studied by fractal theory. The experimental researches on granite mechanics test in undersea deposit indicate that with the increase of load, the granite deformation energy and the fractal dimension of acoustic emission(FDAE) increase gradually. However, after reaching the peak stress of specimen, the fractal dimensions of acoustic emission(FDAEs) decrease and the granite specimen fails. Therefore, the fractal dimension evolution of rock failure can be divided into four stages, which are fissure inoculation stage, fissure growth stage, fissure expansion stage and fracture instability stage, respectively. By calculating and analyzing the damage photographs of rock specimens in Sanshandao Gold Mine, the fractal dimension of rock fissure is 1.4514, which is close to the average value of FDAE during granite destruction, i.e., 1.4693. Similar simulation experiments of undersea mining show that with the excavation proceeding, the FDAE in rock stratum increases gradually, and when the thickness of the isolation roof is less than 40 m, the FDAE begins to decrease, and meanwhile the sign of water inrush emerges. The numerical simulation researches on the plastic zone distribution of undersea mining in Sanshandao Gold Mine indicate that the fractal dimension of plastic zone(FDPZ) where the failure characteristics occur is 1.4598, close to the result of similar simulation experiment of 1.4364, which shows the sign of water inrush. Meanwhile, the thickness of the isolation roof for undersea mining should be more than 40 m, which is consistent with the results of similar simulation experiment. In Sanshandao Gold Mine, the rock fissures in undersea mining were observed by borehole photography and the rock mass deformation was monitored by multi-point displacement meters, and at the same time the fractal dimensions of strata borehole fissure distribution and energy release ratio(ERR) of rock mass were calculated by fractal principle, which are 1.2328 and 1.2685, respectively. The results demonstrate that rock deformation and fissure propagation are both in the second stage of fissure growth, and have not reached the fourth stage of fracture instability. Therefore, the conclusion can be obtained that the undersea mining in Sanshandao Gold Mine is safe at present.
基金Changjiang Scholars Program of the Ministry of Education,Grant/Award Number:Q2018270Outstanding Youth Funding of Anhui Province,Grant/Award Number:OUFAH 1908085J10+2 种基金Jiangsu Students'Innovation and Entrepreneurship Training Program,Grant/Award Number:202111117079YNatural Science Foundation of Jiangsu Province,Grant/Award Number:BK20200044National Natural Science Foundation of China,Grant/Award Numbers:NSFC 21671004,NSFC 21975001,NSFC U1904215。
文摘The ferrocene(Fc)-based metal-organic frameworks(MOFs)are regarded as compelling platforms for the construction of efficient and robust oxygen evolution reaction(OER)electrocatalysts due to their superior conductivity and flexible electronic structure.Herein,density functional theory simulations were addressed to predict the electronic structure regulations of CoFc-MOF by nickel doping,which demonstrated that the well-proposed CoNiFc-MOFs delivered a small energy barrier,promoted conductivity,and well-regulated d-band center.Inspired by these,a series of sea-urchin-like CoNiFc-MOFs were successfully synthesized via a facile solvothermal method.Moreover,the synchrotron X-ray and X-ray photoelectron spectroscopy measurements manifested that the introduction of nickel could tailor the electronic structure of the catalyst and induce the directional transfer of electrons,thus optimizing the rate-determining step of^(*)O→^(*)OOH during the OER process and yielding decent overpotentials of 209 and 252 mV at 10 and 200 mA cm^(−2),respectively,with a small Tafel slope of 39 mV dec^(−1).This work presents a new paradigm for developing highly efficient and durable MOF-based electrocatalysts for OER.
文摘In this study,we investigated the hydrogen evolution reaction(HER)on the(101)facet of pristine and W-doped CoP using the density functional theory.Two types of Co atoms are identified on the catalyst surface:the Co atoms that present the higher d band center are marked as valid sites,whereas the others are marked as invalid sites owing to their weaker H adsorption ability.It is further revealed that W-doping can decrease the d band center of the surface Co atoms,which is beneficial for the HER;however the exposure to W weakens the desorption of H.To address the strong adsorption effect of W,the doping sites and dopant content are analyzed,and the results indicate that 8.4 wt%W doping at the invalid surface Co sites is preferred;moreover,the optimal W content increases to 16.8 wt%when W is inserted into the subsurface.The effect of W doping is weakened when the doping site is far away from the surface.
基金supported by the Fundamental Research Funds for the Central Universities (2020XZZX002-07)the National Natural Science Foundation of China (21776248, 21676246)supported by Major Scientific Project of Zhejiang Lab, Grant/Award Numbers: 2020MC0AD01.
文摘Electrocatalytic oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER)in acidic media are vital for the applications of renewable energy electrolyzers.However,the low mass activity of noble Pt urgently needs to be improved due to the strong binding energetics of oxygen species(*O)with Pt sites.Here we report fine PtxSr alloy(-2 nm)supported on N-doped carb on(NC)pyrolyzing from ZIF-8 as bifunctional electrocatalysts toward ORR and HER in acidic media.The representative Pt_(2)Sr/NC exhibits an onset potential of 0.94 V vs.RHE and half-wave potential of 0.84 V toward ORR,and a low over-potential of 27 mV(10 mA cm^(-2))toward HER,respectively.Significantly,the mass activities of Pt_(2)Sr/NC are 6.2 and 2.6 times higher than that of Pt/C toward ORR(at 0.9 V)and HER(at-30 mV),respectively.Simultaneously,Pt_(2)Sr/NC possesses a retention rate of 90.97%toward acidic ORR after 35000 s of continuous operation.Through density functional theory(DFT)calculations and X-ray photoelectron spectroscopy analysis,the incorporation of Sr into Pt forming Pt_(2)Sr alloy redistributes the electronic structures of Pt-Pt bonds,changing the rate-determining step for the ORR on Pt sites from the formation of*OH from*O to the generation of*OOH along with decreasing the energy barrier,which is also confirmed by the downshift of d band center.Meanwhile,the downshift of d band center also leads to the optimization of the adsorption energy(H*)with Pt,significantly improving Pt_(2)Sr/NC toward HER.
基金supported by the National Natural Science Foundation of China(21875292 and 51902103)Hunan Provincial Natural Science Foundation(2019JJ50037 and 2021JJ30087)+1 种基金Natural Science Foundation of Guangdong Province(2020A1515010798)the Hunan Joint International Laboratory of Advanced Materials and Technology for Clean Energy(2020CB1007)。
文摘Nickel molybdate(NiMoO_(4))attracts superior hydrogen desorption behavior but noticeably poor for efficiently driving the hydrogen evolution reaction(HER)in alkaline media due to the sluggish water dissociation step.Herein,we successfully accelerate the water dissociation kinetics of NiMoO_(4)for prominent HER catalytic properties via simultaneous in situ interfacial engineering with molybdenum dioxide(MoO_(2))and doping with phosphorus(P).The as-synthesized P-doped NiMoO_(4)/MoO_(2)heterostructure nanorods exhibit outstanding HER performance with an extraordinary low overpotential of-23 m V at a current density of 10 m A cm^(-2),which is highly comparable to the performance of the state-of-art Pt/C coated on nickel foam(NF)catalyst.The density functional theory(DFT)analysis reveals the enhanced performance is attributed to the formation of MoO_(2)during the in situ epitaxial growth that substantially reduces the energy barrier of the Volmer pathway,and the introduction of P that provides efficient hydrogen desorption of Ni MoO_(2).This present work creates valuable insight into the utilization of interfacial and doping systems for hydrogen evolution catalysis and beyond.
文摘Oxygen evolution reaction(OER)is the dominant step for plenty of energy conversion and storage technologies.However,the OER suffers from sluggish kinetics and high overpotential due to its complex 4‐electron/proton transfer mechanism.Thus,developing efficient electrocatalysts is particularly urgent to accelerate OER catalysis but still remains a great challenge.Herein,we have synthesized the novel cobalt molybdate nanoflakes(CoMoO_(4)‐O_(v)‐n@GF)with adjustable oxygen vacancies contents by in situ constructing CoMoO_(4) nanoflakes on graphite felt(GF)and annealing treatment under the reduction atmosphere.The best‐performing CoMoO_(4)‐O_(v)‐2@GF with optimal oxygen vacancies content shows splendid electrocatalytic performance with the low overpotential(296 mV at 10 mA cm^(‒2))and also small Tafel slope(62.4 mV dec^(‒1))in alkaline solution,which are comparable to those of the RuO_(2)@GF.The experimental and the density functional theory calculations results reveal that the construction of optimal oxygen vacancies in CoMoO_(4) can expose more active sites,narrow the band‐gap to increase the electrical conductivity,and modulate the free energy of the OER‐related intermediates to accelerate OER kinetics,thus improving its intrinsic activity.
基金Financial support from the National Natural Science Foundation of China(21676216)the Special project of Shaanxi Provincial Education Department(20JC034)+1 种基金GHfund B(202202022563)Hefei Advanced Computing Center。
文摘Rational design of high-performance electrocatalysts for hydrogen evolution reaction(HER)is vital for future renewable energy systems.The incorporation of foreign metal ions into catalysts can be an effective approach to optimize its performance.However,there is a lack of systematic theoretical studies to reveal the quantitative relationships at the electronic level.Here,we develop a multi-level screening methodology to search for highly stable and active dopants for CoP catalysts.The density functional theory(DFT)calculations and symbolic regression(SR)were performed to investigate the relationship between the adsorption free energy(ΔG_(H^(*)))and 10 electronic parameters.The mathematic formulas derived from SR indicate that the difference of work function(ΔΦ)between doped metal and the acceptor plays the most important role in regulatingΔG_(H^(*)),followed by the d-band center(d-BC)of doped system.The descriptor of HER can be expressed asΔG_(H^(*))=1.59×√|0.188ΔΦ+d BC+0.120|1/2-0.166 with a high determination coefficient(R^(2)=0.807).Consistent with the theoretical prediction,experimental results show that the Al-CoP delivers superior electrocatalytic HER activity with a low overpotential of75 m V to drive a current density of 10 mA cm^(-2),while the overpotentials for undoped CoP,Mo-CoP,and V-CoP are 206,134,and 83 m V,respectively.The current work proves that theΔΦis the most significant regulatory parameter ofΔG_(H^(*))for ion-doped electrocatalysts.This finding can drive the discovery of high-performance ion-doped electrocatalysts,which is crucial for electrocatalytic water splitting.
文摘“= everything flows”, Eraclitus, (Ephesus, 535-475 B.C.). If really in Nature everything changes and progresses, then at least two questions arise: 1) how can be these changes entropic but nonetheless somehow predictable without risk of oxymoronic behavior;2) how can Science conform itself to follow this requirement of the Nature. To attempt an answer to these questions, the present paper introduces an ab initio theoretical model aimed to show that physical information is actually nothing else but straightforward quantum and relativistic implication of the concept of evolution.
基金supported by Tulane University.M.K.acknowledges the support by the US Department of Energy under EPSCoR Grant No.DE-SC0012432 with additional support from the Louisiana Board of Regents.
文摘In this paper,we report,for the first time,on the electrochemical catalytic activity of 2D titanium carbonitride MXene for hydrogen evolution reaction(HER).According to our study,2D titanium carbonitride exhibited much higher electrocatalytic activity than its carbide analogues,achieving an onset overpotential of 53 mV and Tafel slope of 86 mV dec^(-1),superior to the titanium carbide with onset overpotential of 649 mV and Tafel slope of 303 mV dec^(-1).The obtained onset overpotential for 2D titanium carbonitride is lower than those of all the reported transition metal carbides MXene catalysts without additives,so far.Density functional theory calculations were conducted to further understand the electrochemical performance.The calculation results show that a greater number of occupied states are active for Ti_(3)CNO_(2),revealing free energy for the adsorption of atomic hydrogen closer to 0 than that of Ti_(3)C_(2)O_(2).Both experimental and calculation studies demonstrate the excellent electrocatalytic behavior of titanium carbonitride.The investigation of 2D titanium carbonitride opens up a promising paradigm for the conscious design of high-performance non-precious metal catalyst for hydrogen generation.
基金financially supported by the National Natural Science Foundation of China under Grants 21473183 and 21303079
文摘In the semiconductor-based photocatalysts for overall water splitting, loading proper cocatalysts play a crucial role in enhancing the photocatalytic activity. In this work, we have chosen Ni_n/α-Ga_2O_3 as a model and provided detailed density functional theory calculations to investigate the function of cocatalysts in hydrogen evolution reaction(HER). We have studied the formation and stability of Ni_n(n = 1–4) cluster on two stable surfaces of α-Ga_2O_3(001) and(012). In a Ni_n/α-Ga_2O_3 system, as the Ni 3d states well overlap with O and Ga states, the excited electrons transferred from Ga to Ni may participate in HER. We theoretically predict that introduction of Nincluster on(012) surface can elevate the Fermi level toward the conduction band, which is favorable for the occurrence of HER. Electrochemical computations are used to explore the mechanism of HER. It is found that, in most of Ni_n/α-Ga_2O_3 systems, the active sites of HER are on Ni_n clusters. Loading Ni_n clusters not only importantly reduces the Gibbs free energy of HER but also improves the reaction activity of surface O and Ga sites in HER. Our calculations reasonably explain the experimental observation on significant enhancement of activity for generating hydrogen after loading nickel oxide cocatalysts.
文摘The paper proposes that the four-component structure of political order consists of state, imagination, rule, and accountability whose mental origins are the social brain, theory of mind, the rational brain, and the empirical brain, respectively. The rational brain and the empirical brain are from the thinking brain. This paper posits that in the evolution of political order, the main function of political order is to pacify changed social structure derived from technological revolution. Therefore, the four technological revolutions (the Upper Paleolithic, Agricultural-Bronze, Iron, and Industrial Revolutions) produce the four changed social structures (linked bands, tribe, mega empire, and modern nation, respectively) whose internal conflicts are pacified by the four political revolutions (the imaginative, hierarchical, thinking, bottom-up political revolutions, respectively) to form the four politics (the imaginative egalitarianism, decentralized hierarchical tribalism, centralized top-down thinking, and multilateral bottom-up thinking politics, respectively). In the competitive West originated from Greece and Middle East, the rule of law is the rational rule of competition among competitors, and the accountability of election is the empirical accountability of competition among competitors. In the cooperative East originated from India and China, the rule of relation is the rational rule of cooperation among kin-friends, and the accountability of professional qualification is the empirical accountability of cooperation among kin-friends. For political order, the two viable politics are competitive liberal democracy based on liberty and cooperative well-off democracy (well-off socialism) based on wellbeing. The direction of political order is middle democracy between liberal democracy and well-off democracy based on the multilateral bottom-up thinking politics.
文摘A common problem in molecular comparative geno- mics is the identification of genes that are under positive, adaptive selection [1]. Such genes are likely to be crucial for speciation, species differentiation, and func- tional specialization. However, discerning the difference between positive selection and relaxation of func- tional constraint can be difficult using current methods. Both processes generally increase the rate of ami- no acid change relative to synonymous changes within coding regions, and unless the amino acid rate is over- whelmingly high across an entire gene, the signature of positive selection can be obscured [2]. Some methodologies do not explicitly determine the difference be- tween a relaxation of functional constraint and positive selection, leaving researchers to determine via other means whether the trajectory of a gene has been specialization or creation of a new function, or removal from the genome via a process of degeneration.