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Evolution based on genome structure: the “diagonal genome universe” 被引量:2
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作者 Kenji Sorimachi 《Natural Science》 2010年第10期1104-1112,共9页
The ratios of amino acid to the total amino acids and those of nucleotides to the total nucleotides in genes or genomes are suitable indexes to compare whole gene or genome characteristics based on the large number of... The ratios of amino acid to the total amino acids and those of nucleotides to the total nucleotides in genes or genomes are suitable indexes to compare whole gene or genome characteristics based on the large number of nucleotides rather than their sequences. As these ratios are strictly calculated from nucleotide sequences, the values are independent of experimental errors. In the present mini-review, the following themes are approached according to the ratios of amino acids and nucleotides to their total numbers in the genome: prebiotic evolution, the chronological precedence of protein and codon formations, genome evolution, Chargaff’s second pa- rity rule, and the origins of life. Amino acid formation might have initially occurred during pre- biotic evolution, the “amino acid world”, and amino acid polymerization might chronologically precede codon formation at the end of prebiotic evolution. All nucleotide alterations occurred synchronously over the genome during biolo- gical evolution. After establishing primitive lives, all nucleotide alterations have been governed by linear formulae in nuclear and organelle genomes consisting of the double-stranded DNA. When the four nucleotide contents against each individual nucleotide content in organelles are expressed by four linear regression lines representing the diagonal lines of a 0.5 square – the “Diagonal Genome Universe”, evolution obeys Chargaff’s second parity rule. The fact that linear regression lines intersect at a single point su- ggests that all species originated from a single life source. 展开更多
关键词 evolution (Prebiotic and Biological) GENOME Origin of Life Chargaffs Parity Rules ORGANELLE Double- and SINGLE-STRAND DNA Amino Acid NUCLEOTIDE Linear Formula
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Diagenesis-porosity evolution and“sweet spot”distribution of low permeability reservoirs:A case study from Oligocene Zhuhai Formation in Wenchang A sag,Pear River Mouth Basin,northern South China Sea 被引量:2
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作者 YOU Li XU Shouli +3 位作者 LI Cai ZHANG Yingzhao ZHAO Zhanjie ZHU Peiyuan 《Petroleum Exploration and Development》 2018年第2期251-263,共13页
The characteristics of low permeability reservoirs and distribution of sweet spots in the Oligocene Zhuhai Formation of Wenchang A sag, Pearl River Basin were investigated by core observation and thin section analysis... The characteristics of low permeability reservoirs and distribution of sweet spots in the Oligocene Zhuhai Formation of Wenchang A sag, Pearl River Basin were investigated by core observation and thin section analysis. The study results show that there develop the fine, medium and coarse sandstone reservoirs of tidal flat–fan delta facies, which are of mostly low permeability and locally medium permeability. There are two kinds of pore evolution patterns: oil charging first and densification later, the reservoirs featuring this pattern are mainly in the third member of Zhuhai Formation between the south fault zone and the sixth fault zone, and the pattern of densification first and gas charging later is widespread across the study area. Strong compaction and local calcium cementation are the key factors causing low permeability of the reservoirs in the Zhuhai Formation. Thick and coarse grain sand sedimentary body is the precondition to form "sweet spot" reservoirs. Weak compaction and cementation, dissolution, early hydrocarbon filling and authigenic chlorite coating are the main factors controlling formation of "sweet spot" reservoir. It is predicted that there develop between the south fault and sixth fault zones the Class Ⅰ "sweet spot" in medium compaction zone, Class Ⅱ "sweet spot" in nearly strong compaction zone, Class Ⅲ "sweet spot" reservoir in the nearly strong to strong compaction zone with oil charging at early stage, and Class IV "sweet spot" reservoir in the strong compaction and authigenic chlorite coating protection zone in the sixth fault zone. 展开更多
关键词 low permeability reservoir pore evolution hydrocarbon charging 'sweet spot' DISTRIBUTION Zhuhai Formation OLIGOCENE Wenchang A SAG northern South China Sea
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"universe collapse model"and its roles in the unification of four fundamental forces and the origin and the evolution of the universe 被引量:1
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作者 Jiapei Dai 《Natural Science》 2012年第4期199-203,共5页
To unify the four known fundamental forces and provide an explanation for the origin and the evolution of the universe are two long-term goals of theoretical physics. Here a “universe collapse model” has been propos... To unify the four known fundamental forces and provide an explanation for the origin and the evolution of the universe are two long-term goals of theoretical physics. Here a “universe collapse model” has been proposed. The universe consists of Matter and No-matter. No-matter is the universal energy that constructs a consistent universe field, presenting a spiral wave motion at the speed of light at the small scale. The partial collapse of the universal energy forms the particles of the universal energy in a variety of sizes, which are called as the elementary particles. These elementary particles form atom and matter, which construct the galaxies. The collapse of the universe field induces the formation of the universe collapse potential (UCP) and universe collapse force (UCF), and the later is represented by four different aspects of the fundamental forces at the large or small scales. The mathematical equation and the derivation of UCP and UCF are described, and possible experimental tests are also suggested. Therefore, this new model may give a novel explanation for the unification of four fundamental forces and the origin and the evolution of the universe. 展开更多
关键词 UNIVERSE COLLAPSE MODEL Field Theories Beyond Standard MODEL String Field Theory Grand Unification MODEL FUNDAMENTAL FORCES Elementary Particles The ORIGIN and evolution of UNIVERSE
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Entropy-enthalpy compensation reveals the crucial role of interfacial solvation in electrocatalytic oxygen evolution
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作者 Peimeng Qiu Lingtong Ji Shengli Chen 《Science China Chemistry》 2026年第2期529-530,共2页
The sluggish kinetics of oxygen evolution reaction(OER)is a significant bottleneck for green hydrogen production via water electrolysis[1].Despite intensive efforts to develop advanced OER electrocatalysts featuring l... The sluggish kinetics of oxygen evolution reaction(OER)is a significant bottleneck for green hydrogen production via water electrolysis[1].Despite intensive efforts to develop advanced OER electrocatalysts featuring low noble-metal content and high activity,high overpotential and rapid degradation at high potentials persist.This inherent trade-off between activity and stability underscores the importance of designing catalysts that can deliver high OER activity at lower operating potentials,thereby efficiently mitigating dissolution and extending durability. 展开更多
关键词 water electrolysis despite green hydrogen production oxygen evolution reaction oer ENTROPY SOLVATION INTERFACIAL oer electrocatalysts COMPENSATION
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Genetic Evolution Analysis of Rabies Virus in Jiangsu Province,China
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作者 Minghui Zhang Yuanfang Qin +8 位作者 Na zhang Yuqiao Liu Jun Yang Xiaonuo Xu Pengcheng Yu Shuqing Liu Qian Liu Xiaoyan Tao Wuyang Zhu 《Biomedical and Environmental Sciences》 2026年第2期245-250,共6页
Rabies is a zoonotic disease with an estimated global mortality of 59,000 people annually and a burden of more than 3.7 million disability-adjusted life years(DALYs)that is caused by a neurotropic lyssavirus[1].Dogs a... Rabies is a zoonotic disease with an estimated global mortality of 59,000 people annually and a burden of more than 3.7 million disability-adjusted life years(DALYs)that is caused by a neurotropic lyssavirus[1].Dogs are the primary source of human rabies,as more than 95%of human cases can be traced to dogs[2,3].China faces a substantial burden of rabies,having endured three major human rabies epidemics,which occurred in the 1950s,1981,and 2007[4].Implementation of various prevention and control measures has decreased the number of human rabies cases from 3,300 in 2007 to 167 in 2024.In China. 展开更多
关键词 rabies virus Jiangsu province neurotropic lyssavirus dogs neurotropic lyssavirus prevention control measures China genetic evolution zoonotic disease
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Evolutionary Origin of Religions and Religious Evolution: Religious Neurosociology
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作者 Dingyu Chung 《Journal of Behavioral and Brain Science》 2018年第9期485-511,共27页
The paper proposes that the evolutionary origin of religions is based on theory of mind as the product of interdependent division of labor between the forest specialist group (women and small children) and the woodlan... The paper proposes that the evolutionary origin of religions is based on theory of mind as the product of interdependent division of labor between the forest specialist group (women and small children) and the woodland specialist group (men) in early hominins who lived in the mixed forest-woodland habitat. To complement each other’s work without interfering each other’s work, one specialist group had to recognize (imagine) that the other specialist group existed to think for themselves and to do different works. The result was theory of mind which is to recognize (imagine) that the others exist to think for themselves. (The forest-woodland groups became the hunter-gatherer groups for the Homo species in the savanna habitat.) Under existential pressure, hominins invented imaginary specialists as imaginary agents who existed to think for themselves and to do different works in imaginary division of labor to enhance survival chance. The result was religion with imaginary behaviors. Therefore, religion is defined as a set of beliefs and behaviors based on theory of mind that produces a shared imagination to enhance survival chance under existential pressure. This paper proposes that the religious evolution consists of the premodern imaginative religion for local society habitat starting from bipedalism, the modern rational imaginative religion for regional society habitat starting from the Axial Age, and the postmodern diverse rational imaginative religion for global society habitat starting from the Information Revolution. In conclusion, the religious brain is the imaginative brain, and the religious social behaviors are imaginary social behaviors. The religious evolution is the evolution of human imagination to enhance survival chance under existential pressure, such as the religious reinforcement of social bonds to enhance the survival chance of social group and the religious relief of stress and anxiety to enhance the survival chance of individuals. 展开更多
关键词 RELIGIOUS Neurosociology evolutionary Origin of RELIGIONS RELIGIOUS evolution Neuroscience Theory of Mind Mental IMMUNE System INGROUP Social RELIGION IMMUNE RELIGION Premodern RELIGION Modern RELIGION Postmodern RELIGION
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Mapping editorial identity and thematic evolution in the Journal of Psychology in Africa(2008-2024):A meta-editorial framework analysis
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作者 Joon-ho Kim 《Journal of Psychology in Africa》 2026年第1期117-130,共14页
This study presents a reflective bibliometric review of 1457 peer-reviewed articles published in the Journal of Psychology in Africa(2008-2024,17 years),using a Meta-Editorial Mapping Framework(MEMF)analysis.The MEMF ... This study presents a reflective bibliometric review of 1457 peer-reviewed articles published in the Journal of Psychology in Africa(2008-2024,17 years),using a Meta-Editorial Mapping Framework(MEMF)analysis.The MEMF integrates citation metrics,keyword novelty ratios,TF-IDF weighting,and cluster-based topic modeling to trace long-term thematic trends and editorial evolution.Findings reveal sustained attention to foundational domains such as mental health,education,and identity,alongside a gradual integration of emergent themes including digital well-being,organizational behavior,and post-pandemic adaptation.Articles with moderate topical novelty(40%-60% new keywords)achieved the highest citation and usage metrics,suggesting that integrative innovation enhances scholarly impact.Clustering analyses indicate that the journal’s content forms overlapping conceptual domains rather than isolated silos.These insights contribute to editorial strategy,authorial positioning,and the future design of regional academic platforms.Moreover,the findings provide evidence supporting the use of the MEMF as a replicable tool for meta-editorial analysis across disciplinary and geographic boundaries. 展开更多
关键词 meta-editorial mapping framework(MEMF) topic evolution keyword novelty bibliometric analysis editorial strategy scholarly engagement Journal of Psychology in Africa
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Analytical Treatment of the Evolutionary (1 + 1)-Dimensional Combined KdV-mKdV Equation via the Novel (G'/G)-Expansion Method 被引量:1
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作者 Md. Nur Alam Fethi Bin Muhammad Belgacem M. Ali Akbar 《Journal of Applied Mathematics and Physics》 2015年第12期1571-1579,共9页
The novel (G'/G)-expansion method is a powerful and simple technique for finding exact traveling wave solutions to nonlinear evolution equations (NLEEs). In this article, we study explicit exact traveling wave sol... The novel (G'/G)-expansion method is a powerful and simple technique for finding exact traveling wave solutions to nonlinear evolution equations (NLEEs). In this article, we study explicit exact traveling wave solutions for the (1 + 1)-dimensional combined KdV-mKdV equation by using the novel (G'/G)-expansion method. Consequently, various traveling wave solutions patterns including solitary wave solutions, periodic solutions, and kinks are detected and exhibited. 展开更多
关键词 Novel (G'/G)-Expansion Method (1 %PLUS% 1)-Dimensional COMBINED KdV-mKdV EQUATION Kink Patterns Nonlinear evolution EQUATION Solitary WAVE SOLUTIONS Traveling WAVE SOLUTIONS
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Thoughts of a Medical Doctor about the Life Periods of Our Earth and the Evolution 被引量:1
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作者 Béla Ralovich 《Open Journal of Applied Sciences》 2018年第9期411-421,共11页
The author thinks that the endless and timeless Universe is a permanent substance and energy flow as well as motion of celestial systems and bodies. Celestial bodies may have physical and biological life. Our Earth ha... The author thinks that the endless and timeless Universe is a permanent substance and energy flow as well as motion of celestial systems and bodies. Celestial bodies may have physical and biological life. Our Earth has both lives which can be divided into different periods of time. Its physical life can mainly be characterized by the atomic evolution, sterility, appearance of water and abiotic chemical reactions. Essence of the biological life is the existence of the living unit. Biological life of our Globe started with the first living unit/microorganism which began to influence on its environment which is a closed system for substance, flora, creature and man but not for hit of celestial bodies and for arrival of different kinds of energy from the space as well as for radiation of heat. The biological life of our Earth can be divided into four parts: before photosynthesis, before mankind, before 1778 and after the industrial revolution. 展开更多
关键词 Energy and Substance Flow Physical LIFE Atomic evolution STERILITY Closed System BIOLOGICAL LIFE and Its Effects on the Environment BIOLOGICAL evolution
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Cultural evolution and spatial-temporal distribution of archaeological sites from 9.5–2.3 ka BP in the Yan-Liao region, China 被引量:3
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作者 YUAN Yuying 《Journal of Geographical Sciences》 SCIE CSCD 2019年第3期449-464,共16页
With basic information from 8353 archaeological sites, this study describes a holistic spatial-temporal distribution pattern of archaeological sites of the prehistoric culture sequence from 9.5 ka BP (ka BP = thousand... With basic information from 8353 archaeological sites, this study describes a holistic spatial-temporal distribution pattern of archaeological sites of the prehistoric culture sequence from 9.5 ka BP (ka BP = thousands of years before 0 BP, where "0 BP" is defined as the year AD 1950) to 2.3 ka BP in the region that extends from the Yanshan Mountains to the Liaohe River Plain(i.e., the Yan-Liao region) in northern China. Based on spatial statistics analysis – including the spatial density of the sites and Geographic Information System nearest-neighbour analysis, combined with a review of environmental and climatic data – this paper analyses cultural evolution, the spatial-temporal features of the archaeological sites and human activities against the backdrop of climatic and environmental changes in this region. The results reveal that prehistoric cultural evolution in the Yan-Liao region is extensively influenced by climatic and environmental changes. The Xinglongwa, Zhaobaogou and Fuhe cultures, which primarily developed during a habitable period from 8.5 ka BP to 6.0 ka BP with strong summer monsoons, have similar maximum density values, spatial patterns and subsistence strategies dominated by hunting-gathering. Significant changes occurred in the Hongshan and Lower Xiajiadian cultures, with a significant increase in numbers and densities of sites and a slump in average nearest-neighbour ratio when the environment began to deteriorate starting in 6.0 ka BP. Additionally, with the onset of a weak summer monsoon and the predominance of primitive agriculture, sites of these two cultures present a different type of concentric circle-shaped pattern in space. As the environment continuously deteriorated with increasing aridity and the spread of steppe, more sites were distributed towards the south, and primitive agriculture was replaced by livestock husbandry in the Upper Xiajiadian culture. The most densely populated areas of the studied cultures are centralized within a limited area. The Laohahe River and Jiaolaihe River basins formed the core area in which most archaeological sites were distributed during the strong summer monsoon period and the first few thousand years of the weak summer monsoon period. 展开更多
关键词 PREHISTORIC CULTURAL evolution archaeological site spatial-temporal distribution climate and environmental change Yanshan MOUNTAINS Liaohe River PLAIN
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Corrigendum to “Optimizing the evolution of strength for lime-stabilized rammed soil” [J Rock Mech Geotech Eng 11(2019)882-891]
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作者 Jair de Jesús Arrieta Baldovino Ronaldo Luis dos Santos Izzo +1 位作者 Eclesielter Batista Moreira Juliana Lundgren Rose 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2020年第1期212-212,共1页
The authors regret that in the paper of Baldovino et al.(2019),published in Journal of Rock Mechanics and Geotechnical Engineering(JRMGE),Eq.(2)must be corrected.Eq.(2)in the original paper describes a formula to calc... The authors regret that in the paper of Baldovino et al.(2019),published in Journal of Rock Mechanics and Geotechnical Engineering(JRMGE),Eq.(2)must be corrected.Eq.(2)in the original paper describes a formula to calculate the unconfined compressive strength(q_u).But Authors wrote it as if it were the formula for calculating the split tensile strength(qt).To amend this error,Eq.(1)and Eq.(2)are the correct expressions for q_u and q_t measurements,respectively. 展开更多
关键词 CORRIGENDUM to J ROCK Mech Geotech ENG 11 Optimizing the evolution of strength for lime-stabilized rammed SOIL
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Evolutionary innovations and genetic diversity in angiosperm centromeres
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作者 Yuhong Huang Chuanye Chen +5 位作者 Xin Wang Yiqian Chen Jingwei Zhou Jianwei Zhang Martin A.Lysak Handong Su 《Molecular Plant》 2026年第2期364-382,共19页
Centromeres are indispensable for accurate chromosome segregation,but are subject to rapid sequence turnover while maintaining conserved functions--a paradox in genome evolution.To unravel this paradox,we integrated o... Centromeres are indispensable for accurate chromosome segregation,but are subject to rapid sequence turnover while maintaining conserved functions--a paradox in genome evolution.To unravel this paradox,we integrated over 400 fully resolved centromeres from 17 diploid angiosperms spanning 180 million years of divergence,along with 1,000+pan-genomic assemblies,resequencing datasets,and congeneric wholegenome sequences.We showed that angiosperm centromere organization is determined by lineagespecific combinations of satellite repeats and transposable elements(TEs),which,in turn,shape distinct epigenetic landscapes and evolutionary trajectories within centromeres.In particular,TE insertion patterns were found to be key drivers of structural diversification and positional shift of centromeres in angiosperms.Intriguingly,population-level analyses revealed considerable plasticity in centromere sequences across species,with satellite repeats serving as focal points of evolutionary change and exhibiting species-specific heterogeneity patterns.Temporal reconstructions across congeneric species revealed the emergence and subsequent differentiation of centromeric repeats,outlining a dynamic continuum from gradual sequence diversification to complete turnover during speciation,often accompanied by karyotype reorganization.By integrating intra-and inter-species comparisons,we propose a unifying framework in which centromere innovation is governed by a delicate interplay between genome evolution,chromosomal shuffling,and selection constraints,resulting in phylogenomic signatures of centromeredriven speciation. 展开更多
关键词 centromere evolution ANGIOSPERMS CENH3 satellite repeats transposable elements SPECIATION
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Damage evolution and constitutive model of limestone with horizontal fissure under the coupled effects of dry-wet cycling and precompression stress
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作者 Shunbo Zhang Zhongping Yang +2 位作者 Yang Gao Miao Liu Shanmeng Hou 《International Journal of Mining Science and Technology》 2026年第1期205-228,共24页
To reveal the influence of coupled effects of dry-wet cycling and precompression stress(CEDWCPS)on the damage evolution of limestone with horizontal fissure(LHF),a series of degradation and uniaxial compression tests ... To reveal the influence of coupled effects of dry-wet cycling and precompression stress(CEDWCPS)on the damage evolution of limestone with horizontal fissure(LHF),a series of degradation and uniaxial compression tests were conducted,and a corresponding piecewise damage constitutive model(PDCM)was established.We found that both dry-wet cycling and precompression stress deteriorate the physical properties,alter the microscopic characteristics,and reduce the mechanical properties of the LHF.These degradations are particularly pronounced under the CEDWCPS,although the magnitude of these changes gradually diminishes with the progression of dry-wet cycling.Meanwhile,they also reduce the deformation degree,prolong the micropore compaction stage,shorten the unstable crack propagation stage,lower the frequency and intensity of AE events,decrease the high-amplitude and high-frequency AE signals,enlarge crack scales,and shorten the crack initiation time.Among the changes of these indicators,the dry-wet cycling plays a dominant role.The crack types of LHF under the CEDWCPS(LHFCEDWCPS)are predominantly tensile cracks,supplemented by shear cracks.The failure mode can be defined as tensileshear composite failure.Finally,the established PDCM effectively captures the nonlinear deformation of micropore and the linear deformation of the matrix in LHFCEDWCPS,with all corresponding R^(2) consistently exceeding 0.97. 展开更多
关键词 Dry-wet cycling Precompression stress Coupled effect Fractured limestone Damage evolution Damage constitutive model
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Sedimentary Characteristics and Evolution of the High-resolution Sequence Stratigraphic Framework of the Taiyuan Formation in the Hangjinqi Area,Northern Ordos Basin
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作者 ZHAO Mingsheng TIAN Jingchun +1 位作者 SU Bingrui ZHANG Xiang 《Acta Geologica Sinica(English Edition)》 2026年第1期54-68,共15页
The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theor... The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theoretical and practical significance for guiding oil and gas exploration.The sedimentary facies and sedimentary evolution of the high-resolution sequence framework of the Carboniferous Taiyuan Formation in the Hangjinqi area have been systematically analyzed for the first time by drilling,logging and seismic data.The results show that four types of sequence interfaces can be identified in the Taiyuan Formation:regional unconformity surfaces,scour surfaces,lithologic-lithofacies transformation surfaces and flooding surfaces.According to the sedimentary response caused by the upward and downward movements of the base level at different levels,the Taiyuan Formation can be divided into 2 long-term cycles(LSC_(1)-LSC_(2)),4 mid-term cycles(MSC_(1)-MSC4)and 7 short-term cycles(SSC_(1)-SSC7).The long-and mid-term cycles correspond to members T_(1)and T_(2)and layers T_(1)-1,T_(1-2),T_(2-1),and T_(2)-2,respectively.Long-term cycles are dominated by C_(1);mid-term cycles are dominated by C_(1)and C_(2),followed by A2;and short-term cycles are dominated by C_(1),C_(2),A1 and A2.Under the high-resolution sequence stratigraphic framework,the Hangjinqi area underwent a transformation of fan delta and tidal flat depositional systems during the Taiyuan Formation sedimentary period.In the MSC_(1)-MSC_(2)stage,owing to a large-scale paleocontinent,the fan delta sedimentary body,which was limited in scale and scope,developed only in the southeastern corner and gradually transitioned basinward to tidal flat facies.In the MSC3-MSC4 stage,as the paleocontinent continuously decreased and the sedimentary range expanded,fan-delta plain sedimentation began in the study area.Several braided distributary channels with poor connectivity developed on the fan-delta plain,and between them were floodplains and peat swamps. 展开更多
关键词 high-resolution sequence framework sedimentary characteristics sedimentary evolution Taiyuan Formation Hangjinqi area northern Ordos Basin
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谁会爱上本土的Evolution?写在布勒集团压铸有限公司中国生产基地落成典礼之后
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作者 王杰 《铸造》 CAS CSCD 北大核心 2005年第4期413-414,共2页
1927年,第一台布勒公司制造的压铸机诞生。1989年,布勒开发出了数字压射端实时控制压铸机。1994年,基于压射端实时控制的大吨位压铸机在瑞士乌兹维尔布勒总部诞生。1998年,大吨位压铸机系列扩展至美国生产。2005年,EvolutionB压铸... 1927年,第一台布勒公司制造的压铸机诞生。1989年,布勒开发出了数字压射端实时控制压铸机。1994年,基于压射端实时控制的大吨位压铸机在瑞士乌兹维尔布勒总部诞生。1998年,大吨位压铸机系列扩展至美国生产。2005年,EvolutionB压铸机在中国无锡组装生产成功。这是布勒公司——以全球压铸行业的领导地位为目标的国际性企业的坚实足迹。 展开更多
关键词 evolution 1989 1994 1998 2005
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Carbon sequestration amount evolution characteristics and reaction mechanisms in coal-based solid waste backfill:A new whole-process carbon sequestration technique
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作者 Nan Zhou Jixiong Zhang +1 位作者 Yuzhe Zhang Hao Yan 《International Journal of Mining Science and Technology》 2026年第1期43-55,共13页
Underground carbon sequestration(CS)by solid waste backfill(SWB)offers an effective pathway for collaborative disposal of coal-based solid waste and CO_(2),where the amount of carbon sequestration is an important eval... Underground carbon sequestration(CS)by solid waste backfill(SWB)offers an effective pathway for collaborative disposal of coal-based solid waste and CO_(2),where the amount of carbon sequestration is an important evaluation parameter.In this study,the concept of whole-process carbon sequestration using coal-based solid waste and CO_(2),including sequential stirring and curing stages,was proposed to evaluate the performance evolution of CS.The results showed that CO_(2) pressure and ambient temperature positively correlated with the CS amount from coal-based SWB.In particular,CO_(2) pressure prevailed in the stirring stage,while the ambient temperature effect was more significant in the curing stage.The CS amounts obtained during the stirring stage alone,the curing stage alone,and two sequential stages ranged from 0.66%–3.10%,3.53%–5.09%,and 5.12%–6.02%,respectively.The functional group and micromorphology analyses revealed that the prevailing mechanism at the CS stirring stage was the stirringdriven gas dissolution-leaching-mineralization reaction,while that at the curing stage was the hydration-driven gas permeation-dissociation-CS reaction.Both were essentially solid-liquid-gas multiphase chemical reactions.The results are instrumental in substantiating the coal-based SWB carbon sequestration evolution patterns and mechanisms and providing data support for waste disposal and carbon emission reduction in the coal industry. 展开更多
关键词 Whole-process carbon sequestration Stirring stage Curing stage Carbon sequestration performance evolution Ambient temperature CO_(2)pressure
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Evolution from Primitive Life to Homo sapiens Based on Visible Genome Structures: The Amino Acid World 被引量:3
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作者 Kenji Sorimachi 《Natural Science》 2009年第2期107-119,共13页
It is not too much to say that molecular biology, including genome research, has progressed based on the determination of nucleotide or amino acid sequences. However, these ap-proaches are limited to the analysis of r... It is not too much to say that molecular biology, including genome research, has progressed based on the determination of nucleotide or amino acid sequences. However, these ap-proaches are limited to the analysis of relatively small numbers of the same genes among spe-cies. On the other hand, by graphical presenta-tion of the ratios of the numbers of amino acids present to the total numbers of amino acids presumed from the target gene(s) or genome or those of the numbers of nucleotides present to the total numbers of nucleotides calculated from the target gene(s) or genome, we can readily draw conclusions from extraordinarily huge data sets integrated by human intelli-gence. 1) Assuming polymerization of amino acids or nucleotides in a simulation analysis based on a random choice, proteins were formed by simple amino acid polymerization, while nucleotide polymerization to form nucleic acids encoding specific proteins needed certain specific control. These results proposed that protein formation chronologically preceded codon formation during the establishment of primitive life forms. In the prebiotic phase, amino acid composition was a dominant factor that determined protein characteristics;the “Amino Acid World”. 2) The genome is constructed homogeneou- sly from putative small units displaying similar codon usages and coding for similar amino acid compositions;the unit is a gene assembly en-coding 3,000 - 7,000 amino acid residues and this unit size is independent not only of genome size, but also of species. 3) In codon evolution, all nucleotide alterna-tions are correlated, not only in coding regions, but also in non-coding regions;the correlations can be expressed by linear formulas;y = ax + b, where “y” and “x” represent nucleotide con-tents, and “a” and “b” are constant. 4) The basic pattern of cellular amino acid compositions obtained from whole cell lysates is conserved from bacteria to Homo sapiens, and resembles that calculated from complete genomes. This basic pattern is characterized by a “star-shape” that changes slightly among species, and changes in amino acid composi-tion seem to reflect biological evolution. 5) Organisms can essentially be classified according to two codon patterns. Biological evolution due to nucleotide sub-stitutions can be expressed by simple linear formulas based on mathematical principles, while natural selection must affect species pre- servation after nucleotide alternations. There-fore, although Darwin’s natural selection is not directly involved in nucleotide alternations, it contributes obviously to the selection of nu-cleotide alternations. Thus, Darwin’s natural selection is doubtless an important factor in biological evolution. 展开更多
关键词 evolution PRIMITIVE LIFE Form Genome NUCLEOTIDE Content Chargaffs PARITY Rules CODON Amino Acids Linear Formula Classification
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Mesozoic multi-direction collision tectonic evolution of the Ordos Basin, China: Insights from the detrital zircon and apatite (U-Th)/He analyses 被引量:1
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作者 Yin Chen Jian-guo Li +1 位作者 Lu-lu Chen Hua-lei Zhao 《China Geology》 2025年第1期141-158,共18页
The Ordos Basin(OB)in the western part of the North China Craton(NCC),was located at the jointed area of multi-plates and has recorded the Mesozoic tectonic characteristics.Its tectonic evolution in the Mesozoic is si... The Ordos Basin(OB)in the western part of the North China Craton(NCC),was located at the jointed area of multi-plates and has recorded the Mesozoic tectonic characteristics.Its tectonic evolution in the Mesozoic is significant to understand the tectonic transformation of the northern margin of the NCC.In this work,the detrital zircon and apatite(U-Th)/He chronological system were analyzed in the northern part of the OB,and have provided new evidence for the regional tectonic evolution.The(U-Th)/He chronological data states the weighted ages of 240‒235 Ma,141 Ma with the peak distribution of 244 Ma,219 Ma,173 Ma,147‒132 Ma.The thermal evolution,geochronological data,and regional unconformities have proved four stages of regional tectonic evolution for the OB and its surroundings in the Mesozoic:(1)The Late Permian-Early Triassic;(2)the Late Triassic-Early Jurassic;(3)the Late Jurassic-Early Cretaceous;(4)the Late Cretaceous-Early Paleogene.It is indicated that the multi-directional convergence from the surrounding tectonic units has controlled the Mesozoic tectonic evolution of the OB.Four-stage tectonic evolution reflected the activation or end of different plate movements and provided new time constraints for the regional tectonic evolution of the NCC in the Mesozoic. 展开更多
关键词 Zircon and Apatite(U-Th)/He Tectonic evolution Geochronology Four stages of regional tectonic Ordos Basin Oil-gas-bearing basin Multi-direction collision Oil-gas exploration engineering MESOZOIC North China Craton
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Triassic Granitic Magmatism at the Northern Margin of the North China Craton: Implications of Geochronology and Geochemistry for the Tectonic Evolution of the Central Asian Orogenic Belt 被引量:7
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作者 CHEN Jingsheng TIAN Dexin +6 位作者 YANG Hao LI Weiwei LIU Miao LI Bin YANG Fan LI Wei WU Zhen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第5期1325-1353,共29页
The early Mesozoic marked an important transition from collisional orogeny to post-orogenic extension at the northern margin of the North China Craton(NCC). In this study, we undertook zircon U-Pb dating and whole-roc... The early Mesozoic marked an important transition from collisional orogeny to post-orogenic extension at the northern margin of the North China Craton(NCC). In this study, we undertook zircon U-Pb dating and whole-rock majorand trace-element geochemical analyses of early Mesozoic granitic rocks in the Chifeng area to establish their geochronological framework, petrogenesis, and implications for the tectonic evolution of the eastern Central Asia Orogenic Belt(CAOB). Zircon U-Pb dating results show that these rocks were emplaced in three stages during the Triassic:(1) syenogranites during 250-248 Ma,(2) granodiorites during 244-243 Ma, and(3) monzogranites and granodiorites during 232-230 Ma. These Triassic granitoids belong to the high-K calc-alkaline series and are evolved I-type granites. They have high SiO2 and low Mg O contents with enrichments in light rare-earth elements, Zr, Hf, Rb, Th, and U, and depletions in Ba, Nb, Ta, Sr, and Eu. These geochemical data indicate that the granitoids were derived from partial melting of a lower-crustal source under relatively low-pressure conditions and subsequently underwent extensive fractional crystallization. Considering both the geochemical data and regional geological information, we propose that the 250-248 Ma syenogranites were emplaced in an extensional environment linked to slab break-off after closure of the Paleo-Asian Ocean(PAO) along the Solonker-Xra Moron-Changchun suture zone. The 244-243 Ma granodiorites were formed in a compressional orogenic setting during collision between the Erguna-Xing’an-Songliao composite block and the NCC. The 232-230 Ma granodiorites and monzogranites were emplaced during the transition from compressional orogeny to post-orogenic extension. Overall, the early Mesozoic tectonic evolution of the Chifeng area can be divided into three main stages:(1) closure of the Paleo-Asian Ocean and extension related to slab break-off during the Early Triassic;(2) continuous collisional compression during the Middle Triassic after closure of the PAO;and(3) post-orogenic extension during the Late Triassic, most probably due to lithospheric delamination after amalgamation of the Erguna-Xing’an-Songliao composite block and the NCC. 展开更多
关键词 TRIASSIC GRANITOIDS zircon U-Pb GEOCHRONOLOGY GEOCHEMISTRY tectonic evolution northern margin of the North China CRATON
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