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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS Klein GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow ATTRACTION REPULSION Shell Theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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In situ atomic-scale observation of size-dependent (de) potassiation and reversible phase transformation in tetragonal FeSe anodes
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作者 Ran Cai Lixia Bao +12 位作者 Wenqi Zhang Weiwei Xia Chunhao Sun Weikang Dong Xiaoxue Chang Ze Hua Ruiwen Shao Toshio Fukuda Zhefei Sun Haodong Liu Qiaobao Zhang Feng Xu Lixin Dong 《InfoMat》 SCIE CAS CSCD 2023年第1期161-171,共11页
Potassium-ion batteries(PIBs)are considered promising alternatives to lithium-ion batteries owing to cost-effective potassium resources and a suitable redox potential of-2.93 V(vs.-3.04 V for Li+/Li).However,the explo... Potassium-ion batteries(PIBs)are considered promising alternatives to lithium-ion batteries owing to cost-effective potassium resources and a suitable redox potential of-2.93 V(vs.-3.04 V for Li+/Li).However,the exploration of appro-priate electrode materials with the correct size for reversibly accommodating large K+ions presents a significant challenge.In addition,the reaction mecha-nisms and origins of enhanced performance remain elusive.Here,tetragonal FeSe nanoflakes of different sizes are designed to serve as an anode for PIBs,and their live and atomic-scale potassiation/depotassiation mechanisms are revealed for the first time through in situ high-resolution transmission electron micros-copy.We found that FeSe undergoes two distinct structural evolutions,sequen-tially characterized by intercalation and conversion reactions,and the initial intercalation behavior is size-dependent.Apparent expansion induced by the intercalation of K+ions is observed in small-sized FeSe nanoflakes,whereas unexpected cracks are formed along the direction of ionic diffusion in large-sized nanoflakes.The significant stress generation and crack extension originating from the combined effect of mechanical and electrochemical interactions are elucidated by geometric phase analysis and finite-element analysis.Despite the different intercalation behaviors,the formed products of Fe and K_(2)Se after full potassiation can be converted back into the original FeSe phase upon depotassiation.In particular,small-sized nanoflakes exhibit better cycling perfor-mance with well-maintained structural integrity.This article presents the first successful demonstration of atomic-scale visualization that can reveal size-dependent potassiation dynamics.Moreover,it provides valuable guidelines for optimizing the dimensions of electrode materials for advanced PIBs. 展开更多
关键词 elucidated by geometric phase analysis and finite-element analysis. Despite the different intercalation behaviors the formed products of Fe and K 2 Se after full potassiation can be converted back into the original FESE phase upon depotassiation. In particular small-sized nanoflakes exhibit better cycling perfor- mance with well-maintained structural integrity. This article presents the first successful demonstration of ATOMIC-SCALE visualization that can reveal size- dependent potassiation dynamics. Moreover it provides valuable guidelines for optimizing the dimensions of electrode materials for advanced PIBs. KEYWOR DS in situ transmission electron microscopy potassium-ion batteries potassium-ion storage mechanism SIZE-DEPENDENT effects TETRAGONAL FESE
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Oxidation Kinetics of Aluminum Powders in a Gas Fluidized Bed Reactor in the Potential Application of Surge Arresting Materials
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作者 Hong Shih 《Materials Sciences and Applications》 2019年第3期253-292,共40页
In this technical paper, the oxidation mechanism and kinetics of aluminum powders are discussed in great details. The potential applications of spherical aluminum powders after oxidation to be part of the surging arre... In this technical paper, the oxidation mechanism and kinetics of aluminum powders are discussed in great details. The potential applications of spherical aluminum powders after oxidation to be part of the surging arresting materials are discussed. Theoretical calculations of oxidation of spherical aluminum powders in a typical gas fluidization bed are demonstrated. Computer software written by the author is used to carry out the basic calculations of important parameters of a gas fluidization bed at different temperatures. A mathematical model of the dynamic system in a gas fluidization bed is developed and the analytical solution is obtained. The mathematical model can be used to estimate aluminum oxide thickness at a defined temperature. The mathematical model created in this study is evaluated and confirmed consistently with the experimental results on a gas fluidization bed. Detail technical discussion of the oxidation mechanism of aluminum is carried out. The mathematical deviations of the mathematical modeling have demonstrated in great details. This mathematical model developed in this study and validated with experimental results can bring a great value for the quantitative analysis of a gas fluidization bed in general from a theoretical point of view. It can be applied for the oxidation not only for aluminum spherical powders, but also for other spherical metal powders. The mathematical model developed can further enhance the applications of gas fluidization technology. In addition to the development of mathematical modeling of a gas fluidization bed reactor, the formation of oxide film through diffusion on both planar and spherical aluminum surfaces is analyzed through a thorough mathematical deviation using diffusion theory and Laplace transformation. The dominant defects and their impact to oxidation of aluminum are also discussed in detail. The well-controlled oxidation film on spherical metal powders such as aluminum and other metal spherical powders can potentially become an important part of switch devices of surge arresting materials, in general. 展开更多
关键词 Aluminum Spherical Power GAS FLUIDIZATION Bed Oxidation mechanism Oxide Growth Rate Gibbs Free Energy Ellingham Diagram Mathematical Modeling Dynamic System Plasma DIFFUSION DIFFUSION Coefficient Crystallographic Defect Vacancy Pressure Temperature Flow Laplace Transform Equation Boundary Condition Ficks Second Law Software Experimental Theoretical SURGE ARRESTING MATERIALS Analytical Solution
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A retrospective view on the history of natural sciences in XX-XXI
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作者 Vladislav Sergeyevich Olkhovsky 《Natural Science》 2010年第3期228-245,共18页
The presented paper is dedicated to a new ret-rospective view on the history of natural sci-ences in XX-XXI cc, partially including the sci-ence philosophy (mainly, the problems of the scientific realism, i.e. the cor... The presented paper is dedicated to a new ret-rospective view on the history of natural sci-ences in XX-XXI cc, partially including the sci-ence philosophy (mainly, the problems of the scientific realism, i.e. the correspondence of science to reality) and also a novel scheme for different classes of sciences with different ob-jects and paradigms. There are analyzed the chosen “great” and “grand” problems of phys-ics (including the comprehension of quantum mechanics, with a recently elaborated new chapter, connected with time as a quantum obs- ervable and time analysis of quantum processes) and also of natural sciences as a whole. The particular attention is paid to the interpretation questions and slightly to the aspects, inevitably connected with the world- views of the res- earchers (which do often constitute a part of the interpretation questions). 展开更多
关键词 SCIENCE history SCIENCE realism paradigm PROBLEM of interpretation and comprehension of QUANTUM mechanics the WAVE-FUNCTION collapse the Einstein-Podolsky-Rosen paradox TIME as a QUANTUM observable canonically conjugated to energy maximal hermitian TIME operator TIME analysis of QUANTUM processes relationship be-tween physics and biology PROBLEM of origin of biologic life REDUCTIONISM cosmologic PROBLEM Big Bang anthropic principle
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Exploring mechanism of hidden,steep obliquely inclined bedding landslides using a 3DEC model:A case study of the Shanyang landslide in Shaanxi Province,China
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作者 Jia-yun Wang Zi-long Wu +3 位作者 Xiao-ya Shi Long-wei Yang Rui-ping Liu Na Lu 《China Geology》 CAS CSCD 2024年第2期303-314,I0001-I0003,共15页
Catastrophic geological disasters frequently occur on slopes with obliquely inclined bedding structures(also referred to as obliquely inclined bedding slopes),where the apparent dip sliding is not readily visible.This... Catastrophic geological disasters frequently occur on slopes with obliquely inclined bedding structures(also referred to as obliquely inclined bedding slopes),where the apparent dip sliding is not readily visible.This phenomenon has become a focal point in landslide research.Yet,there is a lack of studies on the failure modes and mechanisms of hidden,steep obliquely inclined bedding slopes.This study investigated the Shanyang landslide in Shaanxi Province,China.Using field investigations,laboratory tests of geotechnical parameters,and the 3DEC software,this study developed a numerical model of the landslide to analyze the failure process of such slopes.The findings indicate that the Shanyang landslide primarily crept along a weak interlayer under the action of gravity.The landslide,initially following a dip angle with the support of a stable inclined rock mass,shifted direction under the influence of argillization in the weak interlayer,moving towards the apparent dip angle.The slide resistance effect of the karstic dissolution zone was increasingly significant during this process,with lateral friction being the primary resistance force.A reduction in the lateral friction due to karstic dissolution made the apparent dip sliding characteristics of the Shanyang landslide more pronounced.Notably,deformations such as bending and uplift at the slope’s foot suggest that the main slide resistance shifts from lateral friction within the karstic dissolution zone to the slope foot’s resistance force,leading to the eventual buckling failure of the landslide.This study unveils a novel failure mode of apparent dip creep-buckling in the Shanyang landslide,highlighting the critical role of lateral friction from the karstic dissolution zone in its failure mechanism.These insights offer a valuable reference for mitigating risks and preventing disasters related to obliquely inclined bedding landslides. 展开更多
关键词 LANDSLIDE Steep obliquely inclined bedding slope Failure mode Failure mechanism Apparent dip creep-buckling Lateral friction 3DEC model Landslide numerical model Geological hazards survey engineering
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Hydrocarbon generation and storage mechanisms of deepwater shelf shales of Ordovician Wufeng Formation–Silurian Longmaxi Formation in Sichuan Basin, China 被引量:10
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作者 GUO Xusheng LI Yuping +5 位作者 BORJIGEN Tenger WANG Qiang YUAN Tao SHEN Baojian MA Zhongliang WEI Fubin 《Petroleum Exploration and Development》 2020年第1期204-213,共10页
As the hydrocarbon generation and storage mechanisms of high quality shales of Upper Ordovician Wufeng Formation– Lower Silurian Longmaxi Formation remain unclear, based on geological conditions and experimental mode... As the hydrocarbon generation and storage mechanisms of high quality shales of Upper Ordovician Wufeng Formation– Lower Silurian Longmaxi Formation remain unclear, based on geological conditions and experimental modelling of shale gas formation, the shale gas generation and accumulation mechanisms as well as their coupling relationships of deep-water shelf shales in Wufeng–Longmaxi Formation of Sichuan Basin were analyzed from petrology, mineralogy, and geochemistry. The high quality shales of Wufeng–Longmaxi Formation in Sichuan Basin are characterized by high thermal evolution, high hydrocarbon generation intensity, good material base, and good roof and floor conditions;the high quality deep-water shelf shale not only has high biogenic silicon content and organic carbon content, but also high porosity coupling. It is concluded that:(1) The shales had good preservation conditions and high retainment of crude oil in the early times, and the shale gas was mainly from cracking of crude oil.(2) The biogenic silicon(opal A) turned into crystal quartz in early times of burial diagenesis, lots of micro-size intergranular pores were produced in the same time;moreover, the biogenic silicon frame had high resistance to compaction, thus it provided the conditions not only for oil charge in the early stage, but also for formation and preservation of nanometer cellular-like pores, and was the key factor enabling the preservation of organic pores.(3) The high quality shale of Wufeng–Longmaxi Formation had high brittleness, strong homogeneity, siliceous intergranular micro-pores and nanometer organic pores, which were conducive to the formation of complicated fissure network connecting the siliceous intergranular nano-pores, and thus high and stable production of shale gas. 展开更多
关键词 hydrocarbon generation and STORAGE mechanism Upper ORDOVICIAN Wufeng FORMATION Lower SILURIAN Longmaxi FORMATION deep-water SHELF siliceous shale Sichuan Basin pore preservation
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Genomic Instability in Cancer II: 4N-Skewed (90°) Reductive Division via Fragile Sites to Fitness Increase for Solid and Hematological Cancer Beginnings 被引量:2
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作者 Kirsten H. Walen 《Journal of Cancer Therapy》 2019年第7期537-564,共28页
The objective herein was to connect the ontogeny process of diplochromosomal, amitotic, 4n-skewed division-system, to cytogenetic deficiency lesions in satellite, repetitive DNAs, especially in the chromosomal fragile... The objective herein was to connect the ontogeny process of diplochromosomal, amitotic, 4n-skewed division-system, to cytogenetic deficiency lesions in satellite, repetitive DNAs, especially in the chromosomal fragile sites, some 100 distributed over the genome. These latter studies had shown that chemical induced replication-stress led to un-replicated lesions in these fragile sites, which from inaccurate repair processes caused genomic instability. In the chain of events of the ontogeny process to the special tetraploidy, it was proposed that primary damaged human cells could undergo replication stress from repair-process present during cell replication, a suggestion verified by X-ray damaged cells producing the unstable fragile sites (see text). The cancer-importance for therapy is recognition of cell cycle change for the 4n derivative fitness-gained, diploid progeny cells. An open question is whether RB controlling G1 to S-period is mutated at this suggested tumorigenesis initiating phase, and if so, with what consequences for therapy. The fragile site studies further showed that repair of repetitive DNAs could produce two types of genomic changes: single gene mutations and CNVs, which were here shown to be chromosomally located on “borders” to repairing satellite lesions. This genomic placement was found to correspond to mutations identified in tumor sequencing (p53, Rb, MYC), favoring a bad luck location for their cancer “mutational nature”. The CNVs in cancers, are here seen as molecular expressions of long-known cytogenetic HSRs and DMs also with demonstrated origin from amplifications of single genes. Over-expression of oncogenes was hinted of being from duplications, but Drosophila genetics demonstrated the opposite, gene inactivation. The reduced eye-size from dominant, BAR-Ultra-Bar-eye phenotypes, was caused by duplications, inactivating the genetic system for eye-size. The finding of CNVs showing “evasion” of the immune system suggests, inactivation of immune-determining genetics. Since mutated genes on borders to satellite DNAs are a fact in hematological cancers, the 4n-skewed division-system is suggested to replace debated leukemogenesis with fitness-gain from molecular mutations. For these cancers the question is how normal bone marrow cells attain genomic damage for special tetraploidy, which was referred to studies of cells moving in artificial marrow-like substrate, needing serious attention. 展开更多
关键词 Centrifugal 90° Turn CENTROSOME Absence Mitotic Slippage Process Diplochromosomes Mutator mechanism Satellite DNA MUTATIONS Fragile Site Instability Repair MUTATIONS Copy Number Variants CHROMOSOME Nuclear Domains HEMATOLOGIC TRANSLOCATIONS Density Bone Marrow Substrate Abnormal Laminar Proteins Chromosome/Gene UPD Haplo-Insufficiency
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Pathological mechanism of immune disorders in diabetic kidney disease and intervention strategies
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作者 Tong Zhou Yi-Lin Fang +1 位作者 Tian-Tian Tian Gui-Xia Wang 《World Journal of Diabetes》 SCIE 2024年第6期1111-1121,共11页
Diabetic kidney disease is one of the most severe chronic microvascular complications of diabetes and a primary cause of end-stage renal disease.Clinical studies have shown that renal inflammation is a key factor dete... Diabetic kidney disease is one of the most severe chronic microvascular complications of diabetes and a primary cause of end-stage renal disease.Clinical studies have shown that renal inflammation is a key factor determining kidney damage during diabetes.With the development of immunological technology,many studies have shown that diabetic nephropathy is an immune complex disease,and that most patients have immune dysfunction.However,the immune response associated with diabetic nephropathy and autoimmune kidney disease,or caused by ischemia or infection with acute renal injury,is different,and has a complicated pathological mechanism.In this review,we discuss the pathogenesis of diabetic nephropathy in immune disorders and the intervention mechanism,to provide guidance and advice for early intervention and treatment of diabetic nephropathy. 展开更多
关键词 Diabetic kidney disease Immune disorders Pathological mechanism Intervention strategy Kidney damage Diabetic nephropathy INFLAMMASOME IMMUNOGLOBULIN
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Plasticity of photorespiratory carbon concentration mechanism in Sedobassia sedoides(Pall.)Freitag&G.Kadereit under elevated CO_(2)concentration and salinity
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作者 Zulfira RAKHMANKULOVA Elena SHUYSKAYA +2 位作者 Maria PROKOFIEVA Kristina TODERICH Pavel VORONIN 《Journal of Arid Land》 SCIE CSCD 2024年第7期963-982,共20页
Rising atmospheric CO_(2)(carbon dioxide)concentrations and salinization are manifestations of climate change that affect plant growth and productivity.Species with an intermediate C_(3)-C_(4)type of photosynthesis li... Rising atmospheric CO_(2)(carbon dioxide)concentrations and salinization are manifestations of climate change that affect plant growth and productivity.Species with an intermediate C_(3)-C_(4)type of photosynthesis live in a wide range of precipitation,temperature,and soil quality,but are more often found in warm and dry habitats.One of the intermediate C_(3)-C_(4)photosynthetic type is C_(2)photosynthesis with a carbon concentration mechanism(CCM)that reassimilates CO_(2)released via photorespiration.However,the ecological significance under which C_(2)photosynthesis has advantages over C_(3)and C_(4)plants remains largely unexplored.Salt tolerance and functioning of CCM were studied in plants from two populations(P1 and P2)of Sedobassia sedoides(Pall.)Freitag&G.Kadereit Asch.species with C_(2)photosynthesis exposed to 4 d and 10 d salinity(200 mM NaCl)at ambient(785.7 mg/m^(3),aCO_(2)and elevated(1571.4 mg/m^(3),eCO_(2))CO_(2).On the fourth day of salinity,an increase in Na+content,activity catalase,and superoxide dismutase was observed in both populations.P2 plants showed an increase in proline content and a decrease in photosynthetic enzyme content:rubisco,phosphoenolpyruvate carboxylase(PEPC),and glycine decarboxylase(GDC),which indicated a weakening of C_(2)and C_(4)characteristics under salinity.Treatment under 10 d salinity led to an increased Na^(+)content and activity of cyclic electron flow around photosystem I(PSI CEF),a decreased content of K^(+)and GDC in both populations.P1 plants showed greater salt tolerance,which was assessed by the degree of reduction in photosynthetic enzyme content,PSI CEF activity,and changes in relative growth rate(RGR).Differences between populations were evident under the combination of eCO_(2)and salinity.Under long-term salinity and eCO_(2),more salt-tolerant P1 plants had a higher dry biomass(DW),which was positively correlated with PSI CEF activity.In less salt-tolerant P2 plants,DW correlated with transpiration and dark respiration.Thus,S.sedoides showed a high degree of photosynthetic plasticity under the influence of salinity and eCO_(2)through strengthening(P1 plants)and weakening C_(4)characteristics(P2 plants). 展开更多
关键词 photosystems I and II carbon-concentrating mechanism glycine decarboxylase RUBISCO phosphoenolpyruvate carboxylase(PEPC) cyclic electron flow salinity stress DRYLANDS
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One-Electron-Addition to Pentavalent Phosphorus with the Phosphorus-Chlorine Bond as Acceptor Introducing a Fundamental Distinction in Substitution Mechanism between S<sub>N</sub>2(P) and S<sub>N</sub>2(C)
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作者 Henk M.Buck 《Open Journal of Physical Chemistry》 2019年第3期182-191,共10页
An electron-addition, under single-crystal conditions, to pentavalent phosphorus compounds as Cl-P (=O, S) Y, Z with the P-Cl bond as electron-accepting group, is selected as an additional model for SN2(P) like reacti... An electron-addition, under single-crystal conditions, to pentavalent phosphorus compounds as Cl-P (=O, S) Y, Z with the P-Cl bond as electron-accepting group, is selected as an additional model for SN2(P) like reactions. It is demonstrated that the geometric information stored in the tetrahedral configuration (substrate) can be transmitted in the corresponding trigonal bipyramidal (TBP) state for nucleophilic substitution. In this article, we focus on these specific mechanistic aspects of carbon and phosphorus. We consider our study as a contribution to the significance of these (bio)chemical intermediates. 展开更多
关键词 Pentavalent PHOSPHORUS and Carbon Compounds σ%MUL%-Electron-Addition Single-Crystal Electron Spin Resonance (ESR) Model and Ab Initio Calculations Differences in SN2(C) vs. SN2(P) mechanism
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Numerical investigation on detonation cell evolution in a channel with area-changing cross section 被引量:1
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作者 DENG Bo,HU ZongMin,TENG HongHui & JIANG ZongLin Key Laboratory of High Temperature Gas Dynamics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100080,China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期797-808,共12页
The two-dimensional cellular detonation propagating in a channel with area-changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed chemical reaction model. Eff... The two-dimensional cellular detonation propagating in a channel with area-changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed chemical reaction model. Effects of the flow ex-pansion and compression on the cellular detonation cell were investigated to illus-trate the mechanism of the transverse wave development and the cellular detona-tion cell evolution. By examining gas composition variations behind the leading shock,the chemical reaction rate,the reaction zone length,and thermodynamic parameters,two kinds of the abnormal detonation waves were identified. To explore their development mechanism,chemical reactions,reflected shocks and rarefac-tion waves were discussed,which interact with each other and affect the cellular detonation in different ways. 展开更多
关键词 DETONATION cells transverse waves detailed CHEMICAL REACTION model numerical simulation The two-dimensional CELLULAR DETONATION propagating in a channel with area- changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed CHEMICAL REACTION model. Effects of the flow expansion and compression on the CELLULAR DETONATION CELL were investigated to illustrate the mechanism of the transverse wave development and the CELLULAR DETONATION CELL evolution. By examining gas composition variations behind the leading shock the CHEMICAL REACTION rate the REACTION zone length and thermodynamic parameters two kinds of the abnormal DETONATION WAVES were identified. To explore their development mechanism CHEMICAL reactions reflected shocks and rarefaction WAVES were discussed which interact with each other and affect the CELLULAR DETONATION in different ways.
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Multiscale Characteristics and Connection Mechanisms of Attraction Networks:A Trajectory Data Mining Approach Leveraging Geotagged Data
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作者 JIANG Hongqiang WEI Ye +1 位作者 MEI Lin WANG Zhaobo 《Chinese Geographical Science》 SCIE CSCD 2024年第3期533-547,共15页
Urban tourism is considered a complex system,and multiscale exploration of the organizational patterns of attraction networks has become a topical issue in urban tourism,so exploring the multiscale characteristics and... Urban tourism is considered a complex system,and multiscale exploration of the organizational patterns of attraction networks has become a topical issue in urban tourism,so exploring the multiscale characteristics and connection mechanisms of attraction networks is important for understanding the linkages between attractions and even the future destination planning.This paper uses geotagging data to compare the links between attractions in Beijing,China during four different periods:the pre-Olympic period(2004–2007),the Olympic Games and subsequent‘heat period’(2008–2013),the post-Olympic period(2014–2019),and the COVID-19(Corona Virus Disease 2019)pandemic period(2020–2021).The aim is to better understand the evolution and patterns of attraction networks at different scales in Beijing and to provide insights for tourism planning in the destination.The results show that the macro,meso-,and microscales network characteristics of attraction networks have inherent logical relationships that can explain the commonalities and differences in the development process of tourism networks.The macroscale attraction network degree Matthew effect is significant in the four different periods and exhibits a morphological monocentric structure,suggesting that new entrants are more likely to be associated with attractions that already have high value.The mesoscale links attractions according to the common purpose of tourists,and the results of the community segmentation of the attraction networks in the four different periods suggest that the functional polycentric structure describes their clustering effect,and the weak links between clusters result from attractions bound by incomplete information and distance,and the functional polycentric structure with a generally more efficient network of clusters.The pattern structure at the microscale reveals the topological transformation relationship of the regional collaboration pattern,and the attraction network structure in the four different periods has a very similar importance profile structure suggesting that the attraction network has the same construction rules and evolution mechanism,which aids in understanding the attraction network pattern at both macro and micro scales.Important approaches and practical implications for planners and managers are presented. 展开更多
关键词 attraction network travel mobility polycentric structure network motif connectivity mechanism destination management organization(DMO) destination planning Beijing China
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On the Isotope-Like Effect for High-T<sub>c</sub>Superconductors in the Scenario of 2-Phonon Exchange Mechanism for Pairing
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作者 G. P. Malik 《World Journal of Condensed Matter Physics》 2018年第3期109-114,共6页
By generalizing the isotope effect for elemental superconductors (SCs) to the case of pairing in the 2-phonon exchange mechanism for composite SCs, we give here an explanation of the well-known increase in the critica... By generalizing the isotope effect for elemental superconductors (SCs) to the case of pairing in the 2-phonon exchange mechanism for composite SCs, we give here an explanation of the well-known increase in the critical temperature (Tc) of Bi2Sr2CaCu2O8 from 95 K to 110 K and of Bi2Sr2Ca2Cu3O10 from 105 to 115 - 125 K when Bi and Sr in these are replaced by Tl and Ba, respectively. On this basis, we also give the estimated Tcs of some hypothetical SCs, assuming that they may be fabricated by substitutions similar to Bi → Tl and Sr → Ba. 展开更多
关键词 Isotope-Like EFFECT 2-Phonon Exchange mechanism Bi- and Tl-Based High-Tc SCS Suggestions for New Substitutions for Further Enhancement of Tc of the Bi-Based SCS
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The genetic environmental transformation mechanism of coal and oil shale deposits in eastern China’s continental fault basins and the developmental characteristics of the area’s symbiotic assemblages——taking Huangxian Basin as an example 被引量:6
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作者 Dong-Dong Wang Zeng-Xue Li +2 位作者 Hai-Yan Liu Da-Wei Lyu Guo-Qi Dong 《Petroleum Science》 SCIE CAS CSCD 2019年第3期469-491,共23页
Coal and oil shale are two common sedimentary energy sources which are often symbiotically developed in M esozoic- Cenozoic continental fault basins. However, the mechanisms and characteristics of the symbiotic develo... Coal and oil shale are two common sedimentary energy sources which are often symbiotically developed in M esozoic- Cenozoic continental fault basins. However, the mechanisms and characteristics of the symbiotic development are not yet clearly known. In this research study, the typical continental fault basins of eastern China were chosen as examples for the purpose of conducting an examination of the coal and oil shale symbiotic assemblage types, genetic environmental differences, and transformation mechanisms, as well as the development and occurrence characteristics o f different assemblage types. Through a large number of investigations, systematic experimental testing, and sequence stratigraphy studies, the following conclusions were obtained:(1) There were five types of coal and oil shale symbiotic assemblages observed in the continental fault basins,(2) The development of coal and oil shale deposits requires a warm and humid climate, stable structure, abundant organic matter supply, a certain water depth, and a lower terrestrial source debris supply. The observed differences were that the water depth conditions were diversified in the study area, as well as the sources, types, and content of the organic matter.(3) The rapid transformations of the coal and oil shale genetic environments were mainly controlled by the tectonic settings and climatic conditions, which were determined to control the changes in the water depths, salinity,redox conditions, and lake productivity of the genetic environments. Also, in the symbiotic assemblages, genetic environment changes had induced the development of oil shale deposits, which gradually evolved into coal genetic environments.(4) In the isochronous sequence stratigraphic framework of the coal and oil shale symbiotic assemblages, the lake expansion system tracts (EST) were determined to be the most beneficial to the growth o f all the types of assemblages and were characterized by more assemblage development phases and smaller bed thicknesses. From the early to the late stages of the EST, and from the lakesides to lake centers, the thicknesses of the coal seams in the symbiotic assemblages showed trends of thinning, while the thicknesses of the oil shale deposits exhibited increasing trends. The early stages of high stand system tracts were found to be beneficial to the development of the symbiotic assemblages of coal seams overlying the oil shale. This tract type generally presented large bed thicknesses and distribution ranges. The low stand system tract and the late high stand system tract were determined to be unconducive to the development of the symbiotic assemblages. 展开更多
关键词 COAL and oil shale SYMBIOTIC ASSEMBLAGES Genetic environments Conversion mechanism Sequence stratigraphic framework Occurrence CHARACTERISTICS CONTINENTAL fault BASIN
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A fast method to diagnose phase transition from amorphous to microcrystalline silicon 被引量:4
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作者 HOU GuoFu1,2,3,XUE JunMing1,2,3,YUAN YuJie1,2,3,SUN Jian1,2,3,ZHAO Ying1,2,3 & GENG XinHua1,2,3 1 Institute of Photoelectronics,Nankai University,Tianjin 300071,China 2 Tianjin Key Laboratory of Photoelectronic Thin Film Devices and Technique,Tianjin 300071,China 3 Key Laboratory of Optoelectronic Information Science and Technology of Ministry of Education of China,Tianjin 300071,China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期731-736,共6页
A series of hydrogenated silicon thin films were prepared by the radio frequency plasma enhanced chemical vapor deposition method (RF-PECVD) with various si-lane concentrations. The influence of silane concentration o... A series of hydrogenated silicon thin films were prepared by the radio frequency plasma enhanced chemical vapor deposition method (RF-PECVD) with various si-lane concentrations. The influence of silane concentration on structural and elec-trical characteristics of these films was investigated to study the phase transition region from amorphous to microcrystalline phase. At the same time,optical emis-sion spectra (OES) from the plasma during the deposition process were monitored to get information about the plasma properties,Raman spectra were measured to study the structural characteristics of the deposited films. The combinatorial analysis of OES and Raman spectra results demonstrated that the OES can be used as a fast method to diagnose phase transition from amorphous to microcrystalline silicon. At last the physical mechanism,why both OES and Raman can be used to diagnose the phase transition,was analyzed theoretically. 展开更多
关键词 AMORPHOUS silicon MICROCRYSTALLINE silicon PHASE transition optical emission spectroscopy A series of hydrogenated silicon thin films were prepared by the radio frequency plasma enhanced chemical vapor deposition method (RF-PECVD) with various silane concentrations. The influence of silane concentration on structural and electrical characteristics of these films was investigated to study the PHASE TRANSITION region from AMORPHOUS to MICROCRYSTALLINE phase. At the same time optical emission spectra (OES) from the plasma during the deposition process were monitored to get information about the plasma properties Raman spectra were measured to study the structural characteristics of the deposited films. The combinatorial analysis of OES and Raman spectra results demonstrated that the OES can be used as a fast method to DIAGNOSE PHASE TRANSITION from AMORPHOUS to MICROCRYSTALLINE silicon. At last the physical mechanism why both OES and Raman can be used to DIAGNOSE the PHASE transition was analyzed theoretically.
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Study on Sinking-Sliding Failure Mechanism of Perilous Rock at Wangxia in Three Gorges of the Yangtze River, China
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作者 Hong-Kai Chen Sheng-Juan Wang 《Journal of Geoscience and Environment Protection》 2017年第2期30-43,共14页
The giant perilous rock at Wangxia (named Wangxia perilous rock) is representative in Three Gorges of the Yangtze River, China, has threatened badly the navigation of the Yangtze River channel for a long period. The g... The giant perilous rock at Wangxia (named Wangxia perilous rock) is representative in Three Gorges of the Yangtze River, China, has threatened badly the navigation of the Yangtze River channel for a long period. The giant perilous rock is composed of siliceous limestone and argillaceous limestone, and includes two elements marking by W1 and W2, respectively. The W1 is an isolated pillar while the W2 is in clintheriform. The linking segment of dominant fissure in the W2 is composed by moniliform solution funnels at its back, and the locked segment of the dominant fissure at the base of the W2 is composed by two parts. For the locked part of the dominant fissure of the W2, the upper segment shows the same lithology with the perilous rock and it can be simplified as an elastic medium, for the lower segment composed by argillaceous shale and mudstone can be simplified as a strain-softening medium. Introducing the water-softened function, the constitutive curves with two kinds of medium materials for the locked segment in the dominant fissure of the W2 have been proposed. Based on energy principle, the cusp catastrophe model for perilous rock rupture is built and formulas for the transient elastic and impulsive acceleration and the elastic-impulsive velocity of perilous rock catastrophe rupture have been established. By the calculation, the elastic-impulsive acceleration for the catastrophe rupture of the W2 is 531.4 m/s2, while the average elastic-impulsive velocity is 2.608 m/s. Further, it is deduced that the elastic-impulsive velocity at the base of the W2 is about 5.2 m/s. For the transient ruture of the W2, there is a greater speed difference between the top and the base of the W2, which impels the giant perilous rock to be retroverted sliding rupture, coinciding with the fact. Undoubtedly, studies in this paper must play an important role to analyze the catastrophe rupture mechanism of giant perilous rocks at both banks in Three Gorges of the Yangtze River, China. 展开更多
关键词 Sinking-Sliding Failure mechanism Water-Softened Function CATASTROPHE Theory Energy Principle Giant Perilous Rock Three Gorges of the YANGTZE River China
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Fabrication of Silane and Desulfurization Ash Composite Modified Polyurethane and Its Interfacial Binding Mechanism
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作者 吴旺华 CHEN Shuichang +4 位作者 YE Haodong 李世迁 LIN Yuanzhi 陈庆华 XIAO Liren 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期288-297,共10页
Polyurethane/desulfurization ash(PU/DA)composites were synthesized using"one-pot method",with the incorporation of a silane coupling agent(KH550)as a"molecular bridge"to facilitate the integration ... Polyurethane/desulfurization ash(PU/DA)composites were synthesized using"one-pot method",with the incorporation of a silane coupling agent(KH550)as a"molecular bridge"to facilitate the integration of DA as hard segments into the PU molecular chain.The effects of DA content(φ)on the mechanical properties,thermal stability,and hydrophobicity of PU,both before and after the addition of KH550,were thoroughly examined.The results of microscopic mechanism analysis confirmed that KH550 chemically modified the surface of DA,facilitating its incorporation into the polyurethane molecular chain,thereby significantly enhancing the compatibility and dispersion of DA within the PU matrix.When the mass fraction of modified DA(MDA)reached 12%,the mechanical properties,thermal stability,and hydrophobicity of the composites were substantially improved,with the tensile strength reaching 14.9 MPa,and the contact angle measuring 100.6°. 展开更多
关键词 POLYURETHANE silane coupling agent desulfurization ash modification mechanical property HYDROPHOBICITY thermal stability
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Instability mechanism of mining roadway passing through fault at different angles in kilometre-deep mine and control measures of roof cutting and NPR cables
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作者 SUN Xiaoming WANG Jian +6 位作者 ZHAO Wenchao MING Jiang ZHANG Yong LI Zhihu MIAO Chengyu GUO Zhibiao HE Manchao 《Journal of Mountain Science》 SCIE CSCD 2024年第1期236-251,共16页
The angle α between the fault strike and the axial direction of the roadway produces different damage characteristics. In this paper, the research methodology includes theoretical analyses, numerical simulations and ... The angle α between the fault strike and the axial direction of the roadway produces different damage characteristics. In this paper, the research methodology includes theoretical analyses, numerical simulations and field experiments in the context of the Daqiang coal mine located in Shenyang, China. The stability control countermeasure of "pre-splitting cutting roof + NPR anchor cable"(PSCR-NPR) is simultaneously proposed. According to the different deformation characteristics of the roadway, the faults are innovatively classified into three types, with α of type I being 0°-30°, α of type II being 30°-60°, and α of type III being 60°-90°. The full-cycle stress evolution paths during mining roadway traverses across different types of faults are investigated by numerical simulation. Different pinch angles α lead to high stress concentration areas at different locations in the surrounding rock. The non-uniform stress field formed in the shallow surrounding rock is an important reason for the instability of the roadway. The pre-cracked cut top shifted the high stress region to the deep rock mass and formed a low stress region in the shallow rock mass. The high prestressing NPR anchor cable transforms the non-uniform stress field of the shallow surrounding rock into a uniform stress field. PSCR-NPR is applied in the fault-through roadway of Daqiang mine. The low stress area of the surrounding rock was enlarged by 3-7 times, and the cumulative convergence was reduced by 45%-50%. It provides a reference for the stability control of the deep fault-through mining roadway. 展开更多
关键词 Kilometre-deep mine Fault Mining roadway Failure mechanism Pre-splitting cutting roof High pre-stress NPR anchor cable
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Experiments and analysis of gold disk targets irradiated by smoothing beams of Xingguang Ⅱ facilities with 350 nm wavelength
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作者 JIANG ShaoEn,ZHANG BaoHan,LIU ShenYe,YANG JiaMin,SUN KeXu,HUANG TianXuan,DING YongKun & ZHENG ZhiJian National Key Laboratory of Laser Fusion,Laser Fusion Research Center,Mianyang 621900,China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期716-730,共15页
Gold disk targets were irradiated using focusing and beam smoothing methods on Xingguang (XG-Ⅱ) laser facilities with 350 nm wavelength,0.6 ns pulse width and 20-80 Joules energies. Laser absorption,light scattering ... Gold disk targets were irradiated using focusing and beam smoothing methods on Xingguang (XG-Ⅱ) laser facilities with 350 nm wavelength,0.6 ns pulse width and 20-80 Joules energies. Laser absorption,light scattering and X-ray conversion were experimentally investigated. The experimental results showed that laser ab-sorption and scattered light were about 90% and 10%,respectively,under focusing irradiation,but the laser absorption increased 5%-10% and the scattered light about 1% under the condition of beam smoothing. Compared with the case of fo-cusing irradiation,the laser absorption was effectively improved and the scattered light remarkably dropped under uniform irradiation; then due to the decrease in laser intensity,X-ray conversion increased. This is highly advantageous to the in-ertial confinement fusion. However,X-ray conversion mechanism basically did not change and X-ray conversion efficiency under beam smoothing and focusing irra-diation was basically the same. 展开更多
关键词 beam smoothing lens array LASER absorption SCATTERED light X-RAY CONVERSION Gold disk targets were irradiated using focusing and beam SMOOTHING methods on Xingguang (XG-II) LASER facilities with 350 nm wavelength 0.6 ns pulse width and 20-80 Joules energies. LASER absorption light scattering and X-RAY CONVERSION were experimentally investigated. The experimental results showed that LASER ABSORPTION and SCATTERED light were about 90% and 10% respectively under focusing irradiation but the LASER ABSORPTION increased 5%-10% and the SCATTERED light about 1% under the condition of beam smoothing. Compared with the case of focusing irradiation the LASER ABSORPTION was effectively improved and the SCATTERED light remarkably dropped under uniform irradiation then due to the decrease in LASER intensity X-RAY CONVERSION increased. This is highly advantageous to the inertial confinement fusion. However X-RAY CONVERSION mechanism basically did not change and X-RAY CONVERSION efficiency under beam SMOOTHING and focusing irradiation was basically the same.
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Mass-to-Energy Conversion, the Astrophysical Mechanism 被引量:1
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作者 Conrad Ranzan 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第2期520-551,共32页
A new interpretation of the relativistic equation relating total-, momentum-, and mass-energies is presented. With the aid of the familiar energy-relationship triangle, old and new interpretations are compared. And th... A new interpretation of the relativistic equation relating total-, momentum-, and mass-energies is presented. With the aid of the familiar energy-relationship triangle, old and new interpretations are compared. And the key difference is emphasized—apparent relativity versus intrinsic relativity. Mass-to-energy conversion is then brought about by adopting a three-part strategy: 1) Make the motion relative to the universal space medium. This allows the introduction of the concept of intrinsic energy (total, kinetic, and mass energies) as counterpart to the apparent version. 2) Recognize that a particle’s mass property diminishes with increase in speed. This means introducing the concept of intrinsic mass (which varies with intrinsic speed). 3) Impose a change in the particle’s gravitational environment. Instead of applying an electromagnetic accelerating force or energy in order to alter the particle’s total energy, there will simply be an environmental change. Thus, it is shown how to use relativity equations and relativistic motion—in a way that exploits the distinction between apparent and innate levels of reality—to explain the mass-to-energy-conversion mechanism. Moreover, the mechanism explains the 100-percent conversion of mass to energy;which, in turn, leads to an explanation of the mechanism driving astrophysical jets. 展开更多
关键词 RELATIVISTIC MASS ENERGY Kinetic ENERGY MOMENTUM ENERGY Total ENERGY Mass-Energy Conversion INTRINSIC MASS Terminal Neutron Star ENERGY Emission mechanism Astrophysical Jets DSSU Theory
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