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Existence for positive steady states of an eco-epidemiological model
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作者 王雅萍 陈文彦 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期119-122,共4页
An eco-epidemiological model with an epidemic in the predator and with a Holling type Ⅱ function is considered.A system with diffusion under the homogeneous Neumann boundary condition is studied.The existence for a p... An eco-epidemiological model with an epidemic in the predator and with a Holling type Ⅱ function is considered.A system with diffusion under the homogeneous Neumann boundary condition is studied.The existence for a positive solution of the corresponding steady state problem is mainly discussed.First,a prior estimates(positive upper and lower bounds) of the positive steady states of the reaction-diffusion system is given by the maximum principle and the Harnack inequation.Then,the non-existence of non-constant positive steady states by using the energy method is given.Finally,the existence of non-constant positive steady states is obtained by using the topological degree. 展开更多
关键词 eco-epidemiological model existence positive steady states
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A study on the distribution characteristics and existing states of cadmium in the Jinding Pb-Zn deposit,Yunnan Province,China 被引量:2
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作者 YE Lin CHENG Zengtao +2 位作者 PAN Ziping LIU Tiegeng GAO Wei 《Chinese Journal Of Geochemistry》 EI CAS 2010年第3期319-325,共7页
The distribution characteristics and existing state of cadmium in the Jinding Pb-Zn deposit were studied. It was discovered that Cd was mainly distributed in sphalerite as an isomorphic impurity. There was a good corr... The distribution characteristics and existing state of cadmium in the Jinding Pb-Zn deposit were studied. It was discovered that Cd was mainly distributed in sphalerite as an isomorphic impurity. There was a good correlation between Cd and Zn in the primary ore. With the oxidation and resolution of pyrite, sphalerite, sulfide, and etc., many secondary minerals, such as colloform sphalerite and smithsonite, were formed. The distribution of Cd is not symmetrical, and enrichment and dilution were observed in partial area of the oxidation zone in the deposit. Cd, except in external pore space or cracks of secondary minerals as independent minerals, such as greenockite, was mainly distributed in sphalerite as an isomorphic impurity in the secondary sphalerate and smithsonite in the oxidation zone. The research showed that Cd showed a very strong active transfer ability in the oxidation process, not only indicating that supergene leaching might be the main reason for Cd enrichment in some Pb-Zn deposits, but also reflecting that Cd was easily mobilizeed and transferred to pollute ore areas in the oxidation process. Furthermore, Cd in oxidation ore was more easily mobilized and transferred to induce bad hazards for ore areas with the effect from AMD which was produced from oxidation of sulfides. 展开更多
关键词 金顶铅锌矿 氧化镉 特征 作者 云南 中国 次生矿物 氧化过程
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EFFECT OF THE EXISTING STATES OF CHROMIUM ION ON THE COLOR CHARACTERISTICS OF DOPED β-C_2S
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作者 冯修吉 阎培玉 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1990年第2期1-8,共8页
According to the theory of crystal field, the existing state of chromium ions in β-C_2S was studied with optical spectra and EPR. The energy levels of chromium ions were calculated. Chromium ions exist in form of Cr^... According to the theory of crystal field, the existing state of chromium ions in β-C_2S was studied with optical spectra and EPR. The energy levels of chromium ions were calculated. Chromium ions exist in form of Cr^(4+) and Cr^(5+) coordinated with distorted octahedra. The reason of fading of β-C_2S hydrate is that the strength of light absorption declines be- cause of the valence change of chromium ions and chroninm dissolves out and loses in water. 展开更多
关键词 Doped 6-C_2S Color characteristics Existing state Chromium ion
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Effect of existence state of asphaltenes on the asphaltenes-wax interaction in wax deposition
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作者 Yun Lei Han Wang +5 位作者 Shuang-Shuang Li Xue-Qian Liu Hao-Ran Zhu Yu-Ming Gao Hao-Ping Peng Peng-Fei Yu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期507-514,共8页
Asphaltenes are the most elusive substances in waxy crude oil,especially the complex structures,which leads to significant precipitation and aggregation characteristics of asphaltenes,and affects the asphaltenes-wax i... Asphaltenes are the most elusive substances in waxy crude oil,especially the complex structures,which leads to significant precipitation and aggregation characteristics of asphaltenes,and affects the asphaltenes-wax interaction.In this study,the concept of the existence state of asphaltenes was introduced to semi-quantitatively investigate the precipitation and aggregation characteristics of asphaltenes.On this basis,the influence of the existence state of asphaltenes on wax deposition was studied by coldfinger device and high-temperature gas chromatography,and the composition and properties of the deposits were analyzed.Four main findings were made:(1)As the asphaltene concentration increases,the existence state of asphaltenes gradually transitions from dispersed state to aggregated state,and the asphaltene concentration of 0.30 wt%in this study is the starting point of the transition.(2)The existence state of asphaltenes in crude oil does affect the process of wax deposition,as shown in the fact that the dispersed asphaltenes promote the occurrence of wax deposition,while the aggregated asphaltenes can inhibit wax deposition.(3)In the presence of the aggregated asphaltenes,that is,when the asphaltene concentration is higher than 0.30 wt%,the shedding phenomenon of deposit layer was observed,and with the increase of aggregated asphaltenes,the deposit layer fell off earlier.(4)With the increase of the dispersed asphaltenes,the wax appearance temperature(WAT)and wax content of the deposits all showed an increasing trend,while with the appearance of the aggregated asphaltenes,the above situation was reversed.The findings of this study can help for better understanding of the interaction between the asphaltenes and wax in wax deposition. 展开更多
关键词 ASPHALTENES Precipitation/aggregation existence state of asphaltenes Deposition
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Existing State and Partitioning of Rare Earth on Weathered Ores 被引量:55
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作者 池汝安 田君 +5 位作者 李中军 彭翠 吴元欣 李世荣 王存文 周志昂 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第6期756-759,共4页
The existing state and partitioning of rare earth (RE) on weathered ores in Longnan County(LN), Xingfeng County(XF) and Ninghua County(NH) were characterized systematically by standard geological analytical me... The existing state and partitioning of rare earth (RE) on weathered ores in Longnan County(LN), Xingfeng County(XF) and Ninghua County(NH) were characterized systematically by standard geological analytical methods. It is found that RE in the weathered rare earth ores exist as four phases: (a) water soluble, (b) ion-exchangeable, (c) colloidal sediment (oxides), (d) minerals, in which mainly as ion exchangeable phase, accounting for nearly 80% of total RE, with about 20% in the form of colloid sediment phase and mineral phase, but very little as aqueous soluble phase. These rare earth partitioning were mainly chosen mid-heavy RE elements, occupying above 60%, but not equal in the four phases. The mid-heavy RE elements were primarily enriched in the ion exchangeable phase up to 40%, while the containment of cerium dioxide is below 2 %. The cerium deficiency occurs in the ion exchangeable phase in weathered ore. It results from that the Ce^3+ is oxidized into Ce^4+ and changes into CeO2. For LN ore, the containment of Y is high in weathered ore because Y-minerals are abundant in original rock. 展开更多
关键词 weathered existing state partitioning rare earths
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State of rare earth elements in the rare earth deposits of Northwest Guizhou,China 被引量:3
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作者 Peinan He Mingyou He Hai Zhang 《Acta Geochimica》 EI CAS CSCD 2018年第6期867-874,共8页
We studied the states of rare earth elements in ore of the Xianglushan rare earth deposit. Rare earth ore samples were tested and examined by scanning electron microscope, electron probe, and chemical leaching. No ind... We studied the states of rare earth elements in ore of the Xianglushan rare earth deposit. Rare earth ore samples were tested and examined by scanning electron microscope, electron probe, and chemical leaching. No independent rare earth minerals were detected by scanning electron microscope. Elements detected by the electronic probe for the in situ micro-zone of the sample included: O,Al, Si, Ca, Mg, Fe, Ti, K, Na, S, Cl, C, Cu, Cr, V, and Pt.Rare earth elements were not detected by electron probe.(NH_4)_2 SO_4,(NH_4)Cl, NaCl, and H_2 SO_4 were used as reagents in chemical leaching experiments that easily leached out rare earth elements under the action of 10%reagent, indicating that the rare earth elements in ore are mainly in the ionic state rather than present as rare earth minerals. 展开更多
关键词 KAOLINITE Clay rocks Rare earth DEPOSITS Element existence STATE Information extraction NORTHWEST GUIZHOU Province
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Heavy Metal Pollution Along the Yangtze River Stretches of Urban Area in Major Cities 被引量:1
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作者 ZHU Sheng-qingSenior Engineer, Water Resources Protection Bureau of Yangtze valley, Wuhan 430051, China ZANG Xiao-pingSenior Engineer, Water Resources Protection Bureau of Yangtze valley, Wuhan 430051, China 《人民长江》 北大核心 2002年第S1期58-62,共5页
Since the 1970s, Water Environment Monitoring Center of Yangtze valley has been carrying out the monitoring and research work on deposit material in the main stream of Yangtze and finished significant monitoring and r... Since the 1970s, Water Environment Monitoring Center of Yangtze valley has been carrying out the monitoring and research work on deposit material in the main stream of Yangtze and finished significant monitoring and research work on the deposit materials in river sections of urban districts for 21 main cities, such as Panzhihua, Chongqing, Wuhan, Shanghai etc. Based on the monitoring and research results, this paper describes the basic characteristics of deposit materials, the content, distribution and existing state, transfer and transformation characteristics of heavy metal pollutants. The results demonstrate that the heavy metal content in suspended load is higher than that in deposited material for main stream of the Yangtze, the alongshore water zone has been polluted in different degree. Among the 21 main cities on the Yangtze river, the river water pollution along the six cities,i.e. Panzhihua, Yichang, Nanjing, Wuhan, Shanghai, Chongqing, is more serious. 展开更多
关键词 depositd materials heavy metal content level existence state research method stem STREAM of YANGTZE
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Distribution and existing state of indium in the Gejiu Tin polymetallic deposit, Yunnan Province, SW China 被引量:9
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作者 Yubang Li Yan Tao +3 位作者 Feilin Zhu Mingyang Liao Feng Xiong Xianze Deng 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2015年第4期469-483,共15页
The Gejiu tin polymetallic deposit, located in the southwest margin of the South China Belt bordering on the Yangtze Block, is hosted in Triassic carbonates. This study shows that there is an indium enrichment in the ... The Gejiu tin polymetallic deposit, located in the southwest margin of the South China Belt bordering on the Yangtze Block, is hosted in Triassic carbonates. This study shows that there is an indium enrichment in the ores.Indium mainly exists in sphalerite-rich massive sulfide ores with a concentration of 198.3–1570 ppm; the indium concentration in sphalerite ranges from 493.3 up to4781 ppm. The inferred indium reserve in the Gejiu Sn deposit is over 4000 t, indicating that the Gejiu tin deposit is a giant In-bearing Sn-polymetallic deposit, similar to the Dachang and Dulong in southwest China. Sphalerite with a high Fe value(8.05–13.27 wt%) is the predominant indium carrier mineral; meanwhile chalcopyrite plays the secondary indium carrier role. EPMA mapping result shows that indium is likely distributed homogeneously and presented as a substitution for Zn in sphalerite. 展开更多
关键词 锡多金属矿床 个旧锡矿 赋存状态 云南省 高铁闪锌矿 硫化物矿石 电子探针分析
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Mathematical Analysis of Nipah Virus Infections Using Optimal Control Theory 被引量:1
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作者 Jakia Sultana Chandra N. Podder 《Journal of Applied Mathematics and Physics》 2016年第6期1099-1111,共13页
The optimal use of intervention strategies to mitigate the spread of Nipah Virus (NiV) using optimal control technique is studied in this paper. First of all we formulate a dynamic model of NiV infections with variabl... The optimal use of intervention strategies to mitigate the spread of Nipah Virus (NiV) using optimal control technique is studied in this paper. First of all we formulate a dynamic model of NiV infections with variable size population and two control strategies where creating awareness and treatment are considered as controls. We intend to find the optimal combination of these two control strategies that will minimize the cost of the two control measures and as a result the number of infectious individuals will decrease. We establish the existence for the optimal controls and Pontryagin’s maximum principle is used to characterize the optimal controls. The numerical simulation suggests that optimal control technique is much more effective to minimize the infected individuals and the corresponding cost of the two controls. It is also monitored that in the case of high contact rate, controls have to work for longer period of time to get the desired result. Numerical simulation reveals that the spread of Nipah virus can be controlled effectively if we apply control strategy at early stage. 展开更多
关键词 Nipah Virus (NiV) Optimal Control existence of the State existence of the Objective Functional Pontryagin’s Maximum Principle Transversality Condition Optimality Condition Hamiltonian (H)
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States of graphene oxide and surface functional groups amid adsorption of dyes and heavy metal ions
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作者 Zhaoyang Han Ling Sun +6 位作者 Yingying Chu Jing Wang Chenyu Wei Qianlei Jiang Changbao Han Hui Yan Xuemei Song 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第11期197-208,共12页
Water pollution regarding dyes and heavy metal ions is crucial facing the world.How to effectively separate these contaminants from water has been a key issue.Graphene oxide(GO)promises the greenwater world as a long-... Water pollution regarding dyes and heavy metal ions is crucial facing the world.How to effectively separate these contaminants from water has been a key issue.Graphene oxide(GO)promises the greenwater world as a long-lasting spotlight adsorbent material and therefore,harnessing GO has been the research hotspot for over a decade.The state of GO as well as its surface functional groups plays an important role in adsorption.And the way of preparation and structural modification matters to the performance of GO.In this review,the significance of the state of existence of stock GO and surface functional groups is explored in terms of preparation,structural modification,and adsorption.Besides,various adsorbates for GO adsorption are also involved,the discussion of which is rarely established elsewhere. 展开更多
关键词 Stock graphene oxide Surface functional groups existence state ADSORBATES Enhanced adsorption DYES
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EXISTENCE AND CONCENTRATION BEHAVIOR OF GROUND STATE SOLUTIONS FOR A CLASS OF GENERALIZED QUASILINEAR SCHRODINGER EQUATIONS IN R^N
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作者 Jianhua CHEN Xianjiu HUANG +1 位作者 Bitao CHENG Xianhua TANG 《Acta Mathematica Scientia》 SCIE CSCD 2020年第5期1495-1524,共30页
In this article,we study the generalized quasilinear Schrodinger equation-div(ε^2g^2(u)▽u)+ε^2g(u)g′(u)|▽u|^2+V(x)u=K(x)|u|^p-2u,x∈R^N where A≥3,e>0,4<p<,22*,g∈C 1(R,R+),V∈C(R^N)∩L∞(R^N)has a posit... In this article,we study the generalized quasilinear Schrodinger equation-div(ε^2g^2(u)▽u)+ε^2g(u)g′(u)|▽u|^2+V(x)u=K(x)|u|^p-2u,x∈R^N where A≥3,e>0,4<p<,22*,g∈C 1(R,R+),V∈C(R^N)∩L∞(R^N)has a positive global minimum,and K∈C(R^N)∩L∞(R^N)has a positive global maximum.By using a change of variable,we obtain the existence and concentration behavior of ground state solutions for this problem and establish a phenomenon of exponential decay. 展开更多
关键词 generalized quasilinear Schrodinger equation ground state solutions existence concentration behavior
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General Philosophy of Relationism and Its Application to the Political Theory of State and Society and Implications on Natural Sciences
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作者 Igor Janev 《Journal of Philosophy Study》 2020年第8期455-471,共17页
In the examination and study of the general methodology of science and philosophy,we have discovered a common fundamental problem of the“paradox of the basic element”that creates inconsistencies in social and natura... In the examination and study of the general methodology of science and philosophy,we have discovered a common fundamental problem of the“paradox of the basic element”that creates inconsistencies in social and natural theory and general ontology and epistemology.Our study of the interactions of states as major international actors leads us to the conclusion that the unsolved“paradox of the basic element”of the general systems theory(GST)applied in the neorealist doctrine of international relations generates apparent fundamental theoretical weaknesses that have to be resolved.Therefore,herein we propose a solution to the paradox of the basic element on an ontological level by showing that not the element,but rather the relation is the basic“entity”of the system.Such an approach,where the relationship is the most fundamental category and plays a primary role in the system,transforms the GST into a relationist theory(systemic relationism)that includes the relevant systemic variables both in the system as a whole and in its subsystems(or elements).At the same time,due to the equivalence of the“paradox of the basic element”with the paradox of existence of anything or everything(usually formulated as“Why everything[that is]exists”[and not just nothing]),our relationist approach proves to be a good methodological tool for resolving this fundamental question of the general ontology.In addition,this new approach seems to resolve even the basic problem of natural philosophy formulated as the origin of natural force(F).The relationism formulated in our study provides an answer for the existence of anything(E)in relation to nothingness(N),and then through equivalence of basic relation and interaction explains natural force(s)(F)studied in physics.The basic relation in form of irreducible and inseparable{E,N}system or{E}<->{N},(where E—everything,N—nothingness),represents in the physical world a basic irreducible interaction,e.g.,a category of force defined in physics(as intensity of interaction).Thus,by applying the same relationist methodology for understanding the physics of force,we provide a fundamental answer related to the origin of force(in the universe).However,besides natural and social applications,in the present article,we discuss how relationism can be used to resolve controversies in the mainstream political theories of state and to provide new original explanation of the origin of state and causes of social development and change.One of our basic conclusions related to the genesis of state is that this supreme institution was historically(systemically)created as a result of struggle for the monopoly of force when the legal idea of titulus(a title of leader/ruler that could be subject of inheritance)emerged.Rulers(i.e.,first kings,as successor of primitive tribal chiefs)developed and established legitimacy and appropriate binding rules or laws related to that supreme title to justify their special status(titulus). 展开更多
关键词 relationism interaction system force ELEMENT state LAW existence everything
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Extract and Simple Explanation on the Principles of Taiji Studies
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作者 Feng Xu Bin Xiao Weili Qian 《Chinese Medicine and Culture》 2020年第1期29-32,共4页
Taiji studies are a field of study that has its roots in the philosophical thought of the Yi Jing or Book of changes.It integrates the self‑cultivation traditions of Confucianism,Buddhism,and Daoism,and centers its ac... Taiji studies are a field of study that has its roots in the philosophical thought of the Yi Jing or Book of changes.It integrates the self‑cultivation traditions of Confucianism,Buddhism,and Daoism,and centers its academic system mostly on the perspective of the“states view”(jing jie guan).From the standpoint of its philosophical theory,Taiji studies divide the understanding of Dao into three theoretical states:the state of existence(you jie),the state of existence‑nonexistence(you wu jie),and the state of nonexistence(wu jie).It also establishes a theoretical structure that mainly includes“three states and nine axioms,”“One Dao and Nine theory sections,”and“Three practice levels and Nine secrets.”Based on traditional Chinese culture and philosophy,Taiji studies are continuously integrating the essence of them for better understanding and raising,and finally set up a rational school of Taiji Da Dao。 展开更多
关键词 State of existence state of nonexistence Taiji studies Yi Jing(《易经》Book of Changes)
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Two Ways: Representations of the Holocaust in Israeli Art
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作者 Batya Brutin 《International Relations and Diplomacy》 2015年第5期357-368,共12页
The subject of the Holocaust appeared in Israeli art from the establishment of the State and onwards. The integration of the Holocaust in Israeli art through the years was influenced by Israeli society and the Israeli... The subject of the Holocaust appeared in Israeli art from the establishment of the State and onwards. The integration of the Holocaust in Israeli art through the years was influenced by Israeli society and the Israeli art institutional attitude towards the subject and by local historical events. As a result, we witness a development of two directions in Israeli art concerning the Holocaust. One of them has two facets: a massive use of images emphasizing the enormous personal as well as collective destruction of the Jewish nation as the ultimate victim that "the entire world is against us"; While the other facet is that despite the Jewish people emerge battered and humiliated from the Holocaust, they built a country to be an immovable, permanent and safe place for the Jewish nation since "there is no one else except for us to do it". The other direction regarding the Holocaust that developed in Israeli art, examining in an universal approach the Israeli response to the Holocaust through the prism of local historical events occurring since the establishment of the State. Therefore, we see imagery that examines the aggressive impression of the Israelis, as an internal as well as external criticism of what seems as aggression and violence against another nation. In Israel, as well as in other Modem states, art is used as a means for expression of different viewpoints. In this article, I am focusing on the artistic references to the above approaches to the Holocaust. 展开更多
关键词 Holocaust art Israeli art Holocaust and the existence of the State of Israel Moshe Bemstein Itzchak Belfer Naftali Bezem Pinchas Sha'ar Shraga Weil Nathan Rapoport P^I Fux Yaakov Gildor Avner Bar Hama
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Origin of Magnetic Fields of Stellar Objects in the Universe Based on the 5D Projection Theory
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作者 Peter C. W. Fung K. W. Wong 《Journal of Modern Physics》 2017年第4期668-746,共79页
Beginning with a 5D homogeneous universe [1], we have provided a plausible explanation of the self-rotation phenomenon of stellar objects previously with illustration of large number of star samples [2], via a 5D-4D p... Beginning with a 5D homogeneous universe [1], we have provided a plausible explanation of the self-rotation phenomenon of stellar objects previously with illustration of large number of star samples [2], via a 5D-4D projection. The origin of such rotation is the balance of the angular momenta of stars and that of positive and negative charged e-trino pairs, within a 3D &otimes;1D?void of the stellar object, the existence of which is based on conservation/parity laws in physics if one starts with homogeneous 5D universe. While the in-phase e-trino pairs are proposed to be responsible for the generation of angular momentum, the anti-phase but oppositely charge pairs necessarily produce currents. In the 5D to 4D projection, one space variable in the 5D manifold was compacted to zero in most other 5D theories (including theories of Kaluza-Klein and Einstein [3] [4]). We have demonstrated, using the Fermat’s Last Theorem [5], that for validity of gauge invariance at the 4D-5D boundary, the 4th space variable in the 5D manifold is mapped into two current rings at both magnetic poles as required by Perelman entropy mapping;these loops are the origin of the dipolar magnetic field. One conclusion we draw is that there is no gravitational singularity, and hence no black holes in the universe, a result strongly supported by the recent discovery of many stars with masses well greater than 100 solar mass [6] [7] [8], without trace of phenomena observed (such as strong gamma and X ray emissions), which are supposed to be associated with black holes. We analyze the properties of such loop currents on the 4D-5D boundary, where Maxwell equations are valid. We derive explicit expressions for the dipolar fields over the whole temperature range. We then compare our prediction with measured surface magnetic fields of many stars. Since there is coupling in distribution between the in-phase and anti-phase pairs of e-trinos, the generated mag-netic field is directly related to the angular momentum, leading to the result that the magnetic field can be expressible in terms of only the mechanical variables (mass M, radius R, rotation period P)of a star, as if Maxwell equations are “hidden”. An explanation for the occurrence of this “un-expected result” is provided in Section (7.6). Therefore we provide satisfactory answers to a number of “mysteries” of magnetism in astrophysics such as the “Magnetic Bode’s Relation/Law” [9] and the experimental finding that B-P graph in the log-log plot is linear. Moreover, we have developed a new method for studying the relations among the data (M, R, P) during stellar evolution. Ten groups of stellar objects, effectively over 2000 samples are used in various parts of the analysis. We also explain the emergence of huge magnetic field in very old stars like White Dwarfs in terms of formation of 2D Semion state on stellar surface and release of magnetic flux as magnetic storms upon changing the 2D state back to 3D structure. Moreover, we provide an explanation, on the ground of the 5D theory, for the detection of extremely weak fields in Venus and Mars and the asymmetric distribution of magnetic field on the Martian surface. We predict the equatorial fields B of the newly discovered Trappist-1 star and the 6 nearest planets. The log B?&minus;?log P graph for the 6 planets is linear and they satisfy the Magnetic Bode’s relation. Based on the above analysis, we have discovered several new laws of stellar magnetism, which are summarized in Section (7.6). 展开更多
关键词 5D Projection theory Fermat’s Last theorem Perelman’s Mappings Self-Rotation Dipolar MAGNETIC FIELD of Stars LAWS of STELLAR Magnetism LAWS of STELLAR Angular Momentum MAGNETIC Bode’s Law NON-existence of Gravitational Singularity Semion State of Atoms in STELLAR Surface MAGNETIC Storm Planetary MAGNETIC FIELD Maxwell Equations at 4D-5D Boundary MAGNETIC Fields of the Trappist-1 System
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On a class of quasilinear Schrdinger equations 被引量:1
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作者 舒级 张健 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第7期981-986,共6页
A type of quasilinear Schrodinger equations in two space dimensions which describe attractive Bose-Einstein condensates in physics is discussed. By establishing the property of the equation and applying the energy met... A type of quasilinear Schrodinger equations in two space dimensions which describe attractive Bose-Einstein condensates in physics is discussed. By establishing the property of the equation and applying the energy method, the blowup of solutions to the equation are proved under certain conditions. At the same time, by the variational method, a sutficient condition of global existence which is related to the ground state of a classical elliptic equation is obtained. 展开更多
关键词 quasilinear Schrodinger equations BLOWUP global existence ground state Bose-Einstein condensates
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Stability of Schrdinger-Poisson type equations
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作者 黄娟 张健 陈光淦 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第11期1469-1474,共6页
Variational methods are used to study the nonlinear SchrSdinger-Poisson type equations which model the electromagnetic wave propagating in the plasma in physics. By analyzing the Hamiltonian property to construct a co... Variational methods are used to study the nonlinear SchrSdinger-Poisson type equations which model the electromagnetic wave propagating in the plasma in physics. By analyzing the Hamiltonian property to construct a constrained variational problem, the existence of the ground state of the system is obtained. Furthermore, it is shown that the ground state is orbitally stable. 展开更多
关键词 Schrodinger-Poisson type equations ground state existence orbital stability
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The hydrocarbon generation mechanism and the threestage type model of hydrocarbon generation for carbonate source rocks 被引量:2
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作者 王兆云 程克明 《Science China Earth Sciences》 SCIE EI CAS 1997年第3期232-238,共7页
The diagenetic mechanism and process of carbonate rocks, which is different to that of clastic rocks, decides the existence of different existing state organic matters in carbonate rocks. This has been verified by bot... The diagenetic mechanism and process of carbonate rocks, which is different to that of clastic rocks, decides the existence of different existing state organic matters in carbonate rocks. This has been verified by both the microscopic observation of organic petrology and the analysis of organic geochemistry of many samples. Based on the hydrous pyrolysis simulation experiment of the low-mature carbonate rocks, the contrasting study on the yield and their geochemistry characteristics of different existing state soluble organic matters of a series of various maturity samples shows that the different existing state organic matters make different contributions to hydrocarbon generation during every evolution state. So that, the hydrocarbon generation process of carbonate rocks can be summarized as the following three stages; the first is the direct degradation of biogenic bitumen macromolecules during the immature stage, the second is the thermal degradation of a large amount of kerogen at the mature stage, the last stage is the expulsion or release of inclusion organic matter owing to the increased thermal expansion pressure during the high evolution stage. 展开更多
关键词 CARBONATE rocks existing state of organic matter HYDROCARBON GENERATION MECHANISM HYDROCARBON GENERATION model of three-stage type.
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An engineering classification system for the detached granite blocks distributed on slopes
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作者 ZHAO Xiu-cheng ZHAO Xiao-yan +1 位作者 SHEN Wei-gang LUO Gang 《Journal of Mountain Science》 SCIE CSCD 2023年第2期516-531,共16页
Gentle slopes with large amounts of granite blocks are widespread in granitic areas with warm and humid climate.These blocks pose a potential risk to the existing and planned infrastructure.The instability type and ge... Gentle slopes with large amounts of granite blocks are widespread in granitic areas with warm and humid climate.These blocks pose a potential risk to the existing and planned infrastructure.The instability type and geometry of these blocks will influence their motility and destructive power to some extent.This study aims at creating a classification system that can indicate both the shape and the instability type of these blocks and then developing a block removal scheme.The classification system was constructed based on the mechanical stability analysis of blocks on an inclined surface.This analysis identified key factors affecting stability,including block shape,block weathering roundness,the existing state of a block on a slope,and the friction between the block and the slope.The achieved work allowed the establishment of a direct correlation between block geometry and their instability types.The availability of this classification system was validated by field data and experimental data in the literature.The proposal to remove blocks identified as the toppling types,such as cylindrical-toppling types,cuboid-toppling types,cube-toppling types,was put forward to avoid the uneconomical problem of a complete clearance.Meanwhile,this classification provides a foundation for further research on the instability probability of each type of block and the development of a more refined blocks’removal scheme.The classification approach adopted in this paper can provide a reference for the classification of other lithological blocks under similar engineering geological conditions. 展开更多
关键词 South China Granite blocks Classification system Geometry characteristics Instability type Existing state
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再议量子理论的表述形式与诠释
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作者 汪克林 曹则贤 《物理》 CAS 北大核心 2024年第7期472-480,共9页
量子力学建立至今已达百年,关于量子力学仍存留许多困惑与争议。我们注意到可能的原因是状态矢量表示理念的不一致,以及混淆了不同的波函数概率诠释。我们认识到,坚持把状态矢量表示为无量纲的对象,认清波函数的薛定谔、玻恩和狄拉克各... 量子力学建立至今已达百年,关于量子力学仍存留许多困惑与争议。我们注意到可能的原因是状态矢量表示理念的不一致,以及混淆了不同的波函数概率诠释。我们认识到,坚持把状态矢量表示为无量纲的对象,认清波函数的薛定谔、玻恩和狄拉克各自诠释的不同以及薛定谔、玻恩的概率诠释可以经由狄拉克完备性关系联系起来,认识到概率行为出现在无量纲的态矢/波函数与决定性的状态方程之外,则可以消除不少关于量子力学的误解。 展开更多
关键词 状态矢量 波函数 表示理论 概率诠释 完备性关系 存在性 实在性 测量
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