In this study,the micro-failure process and failure mechanism of a typical brittle rock under uniaxial compression are investigated via continuous real-time measurement of wave velocities.The experimental results indi...In this study,the micro-failure process and failure mechanism of a typical brittle rock under uniaxial compression are investigated via continuous real-time measurement of wave velocities.The experimental results indicate that the evolutions of wave velocities became progressively anisotropic under uniaxial loading due to the direction-dependent development of micro-damage.A wave velocity model considering the inner anisotropic crack evolution is proposed to accurately describe the variations of wave velocities during uniaxial compression testing.Based on which,the effective elastic parameters are inferred by a transverse isotropic constitutive model,and the evolutions of the crack density are inversed using a self-consistent damage model.It is found that the propagation of axial cracks dominates the failure process of brittle rock under uniaxial loading and oblique shear cracks develop with the appearance of macrocrack.展开更多
Observing the effects brought by the universal and individual features of the schema inbred in the different languages and cultures, the author touches on the domesticating and foreignizing methods in the process of t...Observing the effects brought by the universal and individual features of the schema inbred in the different languages and cultures, the author touches on the domesticating and foreignizing methods in the process of translation in cultural background from the perspective of schema theory.展开更多
Two spherically symmetric non-singular black hole solutions in Moiler tetrad theory of gravitation have been obtained. Although the two solutions have the same form of metric (spherically symmetric nonsingular black ...Two spherically symmetric non-singular black hole solutions in Moiler tetrad theory of gravitation have been obtained. Although the two solutions have the same form of metric (spherically symmetric nonsingular black hole), their energy contents are different. We use another method given by Gibbons and Hawking to calculate the energy content of these solutions. We also obtained different value of energy. Study the requirements of a satisfactory energymomentum complex given by Moiler we find that the second solution, which behaves as 1/√r, is not transformed as a four-vector under Lorentz transformation.展开更多
Industrial upgrading and transformation is important for China to transform its way of development. To accomplish this task effectively, we need to identify industries with potential comparative advantage. Using the l...Industrial upgrading and transformation is important for China to transform its way of development. To accomplish this task effectively, we need to identify industries with potential comparative advantage. Using the latest data on international trade of products, this paper verifies the premise of heterogeneity of product space of the evolutionary theory of comparative advantage, and analyses the evolution of product space of China and most countries in the world. The paper makes predictions on China "s industries with potential comparative advantage in near terms using the product space theory, and carries out thorough discussion on the evolutionary track of industries under different proximity thresholds. The basic conclusion is that even as China's number of industries with comparative advantage is larger than the global average, its industrial upgrading capacity is limited, as it has fewer industries with potential comparative advantage and lower sustainability in the current sectors than the world average. China faces a dilemma in the process of industrial upgrading, as a rapid upgrading would cause a shock to current economic growth, and a slow one would not maintain sustainable growth. With limited industrial upgrading capacity, the best structure adjustment and upgrading strategy is to give full play to the advantage of China's industrial diversification and combination to achieve an inclusive upgrading.展开更多
Alienated labor, also known as labor alienation, was a concept with historical creativity, which was first raised in Marx' s Economic and Philosophical Manuscripts of 1844. The Manuscripts was important works of Marx...Alienated labor, also known as labor alienation, was a concept with historical creativity, which was first raised in Marx' s Economic and Philosophical Manuscripts of 1844. The Manuscripts was important works of Marx, in which the social relations of capitalism private ownership were analyzed by Marx using the concept of alienated labor. A deep analysis was conducted by Marx from the specific historical facts, in which the rational kernel of the alienated problem in the social relations of capitalism was mentioned. Specifically, the alienated labor theory was analyzed from the relationship of laborers with their labor products and labor itself, human' s essence, and other people under the condition of the capitalist private ownership; the "ought to be" ethical characteristics of labors were expounded from the perspective of ethics, and the abnormal labor relations in the process of capitalist production were ethically reviewed and criticized. Therefore, rich economic ethics thoughts were contained in Marx' s analysis of the alienated labor theory.展开更多
Although there are diverse bond features of Ti and O atoms,so far only several isomers have been reported for each(TiO_(2))n cluster.Instead of the widely used global optimization,in this work,we search for the low-ly...Although there are diverse bond features of Ti and O atoms,so far only several isomers have been reported for each(TiO_(2))n cluster.Instead of the widely used global optimization,in this work,we search for the low-lying isomers of(TiO_(2))_(n)(n=2-8)clusters with up to 10000 random sampling initial structures.These structures were optimized by the PM6 method,followed by density functional theory calculations.With this strategy,we have located many more low-lying isomers than thosereported previously.The number of isomers increases dramatically with the size of the cluster,and about 50 isomers were found for(TiO_(2))_(7) and(TiO_(2))_(8) with the energy within 30 kcal/mol.Furthermore,new lowest isomers have been located for(TiO_(2))_(5) and(TiO_(2))_(8),and isomers with three terminal oxygen atoms,five coordinated oxygen atoms as well as six coordinated titanium atoms have been located.Our work highlights the diverse structural features and a large number of isomers of small TiO_(2) clusters.展开更多
The potential energy landscape of the neutral Ni_(2)(CO)_(5) complex was re-examined.A new C_(2v) structure with double bridging carbonyls is found to compete with the previously proposed triply carbonyl-bridged D_(3h...The potential energy landscape of the neutral Ni_(2)(CO)_(5) complex was re-examined.A new C_(2v) structure with double bridging carbonyls is found to compete with the previously proposed triply carbonyl-bridged D_(3h) isomer for the global minimum of Ni_(2)(CO)_(5).Despite that the tri-bridged isomer possesses the more favored(18,18)configuration,where both metal centers satisfy the 18-electron rule,the neutral Ni_(2)(CO)_(5) complex prefers the di-bridged geometry with(18,16)configuration.The isomerization energy decomposition analysis reveals that the structural preference is a consequence of the maximization of electrostatic and orbital interactions.展开更多
According to the Geological settings and the distributed laws of ore bodies and previous research re- suits, combining with latest theories and new methods of geological prospecting, the authors proposed prospec- ting...According to the Geological settings and the distributed laws of ore bodies and previous research re- suits, combining with latest theories and new methods of geological prospecting, the authors proposed prospec- ting thoughts for substituted resources in Laozuoshan gold deposit. After ore prospecting in two years, nine new blind ore bodies were found, among which four ore bodies contain 4218. 1 kg inferred intrinsic economic re- sources ( 333 ), and mitigate the crisis situation of mine reserves. At the same time, lots of significant geophysi- cal and geochemical anomalies were found in the peripheral, which provide a basis for further prospecting.展开更多
Within the bonded tableau unitary group approach (BTUGA), a scheme, combined with Pauling’s resonance theory to select the predominant valence bond structures for VB calculations, is proposed. This scheme ensures a r...Within the bonded tableau unitary group approach (BTUGA), a scheme, combined with Pauling’s resonance theory to select the predominant valence bond structures for VB calculations, is proposed. This scheme ensures a reliable and illustrative bonding picture in the description of chemical reactions, as exemplified by the isomerization reaction HNC?HCN. The computation results account for important bonding features about this isomerization at the ab initio level and explore the mechanism of phenomena such as (i) HCN is more stable than HNC; (ii) the C-N bond first lengthens and then shortens in the vicinity of the transition state; (iii) only H-atom migration is observed in the isomerization process, without the breaking of the CN bond. Our results demonstrate that only a few bonded tableau functions are sufficient enough to provide a visual and reliable bonding picture.展开更多
Heterogeneous molecular catalysts,such as metal phthalocyanines,are efficient electrocatalysts for CO_(2) reduction reaction(CO_(2)RR).However,the rational design and synthesis of a molecular catalyst-based heterostru...Heterogeneous molecular catalysts,such as metal phthalocyanines,are efficient electrocatalysts for CO_(2) reduction reaction(CO_(2)RR).However,the rational design and synthesis of a molecular catalyst-based heterostructure for CO_(2)RR remains challenging.Herein,we developed a crystalline bimetallic phthalocyanine heterostructure electrocatalyst(CoPc/FePc HS),which achieved an excellent CO_(2)-to-CO conversion efficiency(99%)and outstanding long-term stability after 10 h of electrocatalysis.Density functional theory calculations revealed that the enhancement of CO_(2)RR performance could be attributed to the distinct electron transfer pattern between FePc and CoPc.The heterostructural engineering in molecular catalysts would inspire a unique approach for improving CO_(2)RR performance.展开更多
Using molecular dynamics with embedded-atom-type interatomicpotentials, we simulated the melting behavior of a spherical Ag3055 cluster coated with Ni. The semi-coherent Ag/Ni interface formed at low temperatures acts...Using molecular dynamics with embedded-atom-type interatomicpotentials, we simulated the melting behavior of a spherical Ag3055 cluster coated with Ni. The semi-coherent Ag/Ni interface formed at low temperatures acts as an effective barrier against the surface melting and leads to a substantial superheating of the Ag cluster. The melting point was found to be about 100 K above the equilibrium melting point of the bulk Ag crystal (1230 K±15 K) and about 290 K above that (1040 K) of the free Ag3055 cluster. A superheating of 70 K was observed in the high-temperature differential scanning calorimetry measurement for Ag particles with a mean size of 30 nm embedded in Ni matrix prepared by means of melt-spinning. Melting is initiated locally at the defective interfacial area and then propagates inwards, suggesting a heterogeneously nucleated melting event at the Ag/Ni interface.展开更多
Identifying the causes of diversification is central to evolutionary biology. The ecological theory of adaptive diversi- fication holds that the evolution of phenotypic differences between populations and species--and...Identifying the causes of diversification is central to evolutionary biology. The ecological theory of adaptive diversi- fication holds that the evolution of phenotypic differences between populations and species--and the formation of new spe- cies-stems from divergent natural selection, often arising from competitive interactions. Although increasing evidence suggests that phenotypic plasticity can facilitate this process, it is not generally appreciated that competitively mediated selection often also provides ideal conditions for phenotypic plasticity to evolve in the first place. Here, we discuss how competition plays at least two key roles in adaptive diversification depending on its pattern. First, heterogenous competition initially generates heterogeneity in resource use that favors adaptive plasticity in the form of "inducible competitors". Second, once such competitively induced plas- ticity evolves, its capacity to rapidly generate phenotypic variation and expose phenotypes to alternate selective regimes allows populations to respond readily to selection favoring diversification, as may occur when competition generates steady diversifying selection that permanently drives the evolutionary divergence of populations that use different resources. Thus, competition plays two important roles in adaptive diversification---one well-known and the other only now emerging--mediated through its effect on the evolution ofphenotypic plasticity展开更多
基金Projects(41502283,41772309)supported by the National Natural Science Foundation of ChinaProject(2017YFC1501302)supported by the National Key Research and Development Program of ChinaProject(2017ACA102)supported by the Major Program of Technological Innovation of Hubei Province,China。
文摘In this study,the micro-failure process and failure mechanism of a typical brittle rock under uniaxial compression are investigated via continuous real-time measurement of wave velocities.The experimental results indicate that the evolutions of wave velocities became progressively anisotropic under uniaxial loading due to the direction-dependent development of micro-damage.A wave velocity model considering the inner anisotropic crack evolution is proposed to accurately describe the variations of wave velocities during uniaxial compression testing.Based on which,the effective elastic parameters are inferred by a transverse isotropic constitutive model,and the evolutions of the crack density are inversed using a self-consistent damage model.It is found that the propagation of axial cracks dominates the failure process of brittle rock under uniaxial loading and oblique shear cracks develop with the appearance of macrocrack.
文摘Observing the effects brought by the universal and individual features of the schema inbred in the different languages and cultures, the author touches on the domesticating and foreignizing methods in the process of translation in cultural background from the perspective of schema theory.
文摘Two spherically symmetric non-singular black hole solutions in Moiler tetrad theory of gravitation have been obtained. Although the two solutions have the same form of metric (spherically symmetric nonsingular black hole), their energy contents are different. We use another method given by Gibbons and Hawking to calculate the energy content of these solutions. We also obtained different value of energy. Study the requirements of a satisfactory energymomentum complex given by Moiler we find that the second solution, which behaves as 1/√r, is not transformed as a four-vector under Lorentz transformation.
基金Studies on Monitoring and Risk Assessment of Industrial and Economic Operation, Innovation Project of the Chinese Academy of Social Sciences, Transformation Strategy of Industrial Competitive Advantage and Evolution of Global Division of Labor, Major Fund Program of National Natural Science Foundation of China (Grant No. 098-ZD035).
文摘Industrial upgrading and transformation is important for China to transform its way of development. To accomplish this task effectively, we need to identify industries with potential comparative advantage. Using the latest data on international trade of products, this paper verifies the premise of heterogeneity of product space of the evolutionary theory of comparative advantage, and analyses the evolution of product space of China and most countries in the world. The paper makes predictions on China "s industries with potential comparative advantage in near terms using the product space theory, and carries out thorough discussion on the evolutionary track of industries under different proximity thresholds. The basic conclusion is that even as China's number of industries with comparative advantage is larger than the global average, its industrial upgrading capacity is limited, as it has fewer industries with potential comparative advantage and lower sustainability in the current sectors than the world average. China faces a dilemma in the process of industrial upgrading, as a rapid upgrading would cause a shock to current economic growth, and a slow one would not maintain sustainable growth. With limited industrial upgrading capacity, the best structure adjustment and upgrading strategy is to give full play to the advantage of China's industrial diversification and combination to achieve an inclusive upgrading.
文摘Alienated labor, also known as labor alienation, was a concept with historical creativity, which was first raised in Marx' s Economic and Philosophical Manuscripts of 1844. The Manuscripts was important works of Marx, in which the social relations of capitalism private ownership were analyzed by Marx using the concept of alienated labor. A deep analysis was conducted by Marx from the specific historical facts, in which the rational kernel of the alienated problem in the social relations of capitalism was mentioned. Specifically, the alienated labor theory was analyzed from the relationship of laborers with their labor products and labor itself, human' s essence, and other people under the condition of the capitalist private ownership; the "ought to be" ethical characteristics of labors were expounded from the perspective of ethics, and the abnormal labor relations in the process of capitalist production were ethically reviewed and criticized. Therefore, rich economic ethics thoughts were contained in Marx' s analysis of the alienated labor theory.
基金supported by the National Natural Science Foundation of China(No.92061114 and No.21873096)the Chinese Academy of Sciences(XDB17010200)。
文摘Although there are diverse bond features of Ti and O atoms,so far only several isomers have been reported for each(TiO_(2))n cluster.Instead of the widely used global optimization,in this work,we search for the low-lying isomers of(TiO_(2))_(n)(n=2-8)clusters with up to 10000 random sampling initial structures.These structures were optimized by the PM6 method,followed by density functional theory calculations.With this strategy,we have located many more low-lying isomers than thosereported previously.The number of isomers increases dramatically with the size of the cluster,and about 50 isomers were found for(TiO_(2))_(7) and(TiO_(2))_(8) with the energy within 30 kcal/mol.Furthermore,new lowest isomers have been located for(TiO_(2))_(5) and(TiO_(2))_(8),and isomers with three terminal oxygen atoms,five coordinated oxygen atoms as well as six coordinated titanium atoms have been located.Our work highlights the diverse structural features and a large number of isomers of small TiO_(2) clusters.
基金supported by the National Natural Science Foundation of China(No.21571119 and No.21603130)the Shanxi Province Science Foundation for Youths(No.201901D211395)+1 种基金the 1331 Engineering of Shanxi Provincethe Start-up fund from Shanxi Normal University。
文摘The potential energy landscape of the neutral Ni_(2)(CO)_(5) complex was re-examined.A new C_(2v) structure with double bridging carbonyls is found to compete with the previously proposed triply carbonyl-bridged D_(3h) isomer for the global minimum of Ni_(2)(CO)_(5).Despite that the tri-bridged isomer possesses the more favored(18,18)configuration,where both metal centers satisfy the 18-electron rule,the neutral Ni_(2)(CO)_(5) complex prefers the di-bridged geometry with(18,16)configuration.The isomerization energy decomposition analysis reveals that the structural preference is a consequence of the maximization of electrostatic and orbital interactions.
文摘According to the Geological settings and the distributed laws of ore bodies and previous research re- suits, combining with latest theories and new methods of geological prospecting, the authors proposed prospec- ting thoughts for substituted resources in Laozuoshan gold deposit. After ore prospecting in two years, nine new blind ore bodies were found, among which four ore bodies contain 4218. 1 kg inferred intrinsic economic re- sources ( 333 ), and mitigate the crisis situation of mine reserves. At the same time, lots of significant geophysi- cal and geochemical anomalies were found in the peripheral, which provide a basis for further prospecting.
基金supported by the Key Project of Ministry of Education for Science and Technology(Grant No.20021002)the Major Key Project of Natural Science Foundation of Fujian Province(Grant No.2002F010).
文摘Within the bonded tableau unitary group approach (BTUGA), a scheme, combined with Pauling’s resonance theory to select the predominant valence bond structures for VB calculations, is proposed. This scheme ensures a reliable and illustrative bonding picture in the description of chemical reactions, as exemplified by the isomerization reaction HNC?HCN. The computation results account for important bonding features about this isomerization at the ab initio level and explore the mechanism of phenomena such as (i) HCN is more stable than HNC; (ii) the C-N bond first lengthens and then shortens in the vicinity of the transition state; (iii) only H-atom migration is observed in the isomerization process, without the breaking of the CN bond. Our results demonstrate that only a few bonded tableau functions are sufficient enough to provide a visual and reliable bonding picture.
基金supported by the National Natural Science Foundation of China(22071172,91833306,21875158,51633006,and 51733004).
文摘Heterogeneous molecular catalysts,such as metal phthalocyanines,are efficient electrocatalysts for CO_(2) reduction reaction(CO_(2)RR).However,the rational design and synthesis of a molecular catalyst-based heterostructure for CO_(2)RR remains challenging.Herein,we developed a crystalline bimetallic phthalocyanine heterostructure electrocatalyst(CoPc/FePc HS),which achieved an excellent CO_(2)-to-CO conversion efficiency(99%)and outstanding long-term stability after 10 h of electrocatalysis.Density functional theory calculations revealed that the enhancement of CO_(2)RR performance could be attributed to the distinct electron transfer pattern between FePc and CoPc.The heterostructural engineering in molecular catalysts would inspire a unique approach for improving CO_(2)RR performance.
基金This work was supported by the Ministry of Science and Technology of China (Grant No. 1999064505)the National Natural Science Foundation of China (Grant Nos. 59801011, 59931030 and 59841004) the Max-Planck-Society of Germany.
文摘Using molecular dynamics with embedded-atom-type interatomicpotentials, we simulated the melting behavior of a spherical Ag3055 cluster coated with Ni. The semi-coherent Ag/Ni interface formed at low temperatures acts as an effective barrier against the surface melting and leads to a substantial superheating of the Ag cluster. The melting point was found to be about 100 K above the equilibrium melting point of the bulk Ag crystal (1230 K±15 K) and about 290 K above that (1040 K) of the free Ag3055 cluster. A superheating of 70 K was observed in the high-temperature differential scanning calorimetry measurement for Ag particles with a mean size of 30 nm embedded in Ni matrix prepared by means of melt-spinning. Melting is initiated locally at the defective interfacial area and then propagates inwards, suggesting a heterogeneously nucleated melting event at the Ag/Ni interface.
基金Acknowledgements We thank Zhi-Yun Jia for inviting us to submit this paper to a special column on phenotypic plasticity. Three anonymous reviewers provided valuable commentary that encouraged us to improve this work. We also wish to ac- knowledge the long term funding for plasticity research pro- vided by the U.S. National Science Foundation to DP, and the Natural Sciences and Engineering Research Council of Can- ada to BR. Finally, collaboration on this specific project was directly supported through a short-term fellowship to BR by the National Evolutionary Synthesis Center (NESCent funded by NSF #EF-0905606).
文摘Identifying the causes of diversification is central to evolutionary biology. The ecological theory of adaptive diversi- fication holds that the evolution of phenotypic differences between populations and species--and the formation of new spe- cies-stems from divergent natural selection, often arising from competitive interactions. Although increasing evidence suggests that phenotypic plasticity can facilitate this process, it is not generally appreciated that competitively mediated selection often also provides ideal conditions for phenotypic plasticity to evolve in the first place. Here, we discuss how competition plays at least two key roles in adaptive diversification depending on its pattern. First, heterogenous competition initially generates heterogeneity in resource use that favors adaptive plasticity in the form of "inducible competitors". Second, once such competitively induced plas- ticity evolves, its capacity to rapidly generate phenotypic variation and expose phenotypes to alternate selective regimes allows populations to respond readily to selection favoring diversification, as may occur when competition generates steady diversifying selection that permanently drives the evolutionary divergence of populations that use different resources. Thus, competition plays two important roles in adaptive diversification---one well-known and the other only now emerging--mediated through its effect on the evolution ofphenotypic plasticity