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Origin of the Dashuigou independent tellurium deposit at Qinghai–Xizang Plateau: constraints from the light stable isotopes C, O, and H
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作者 Jianzhao Yin Yuhong Chao +2 位作者 Haoyu Yin Hongyun Shi Shoupu Xiang 《Acta Geochimica》 EI CAS CSCD 2024年第2期385-398,共14页
By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)... By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)O and δ^(13)C isotope signatures of dolomite samples vary between 10.2 and 13.0‰,and between−7.2 and−5.2‰,respectively,implying that the carbon derives from the upper mantle.δD and δ^(18) O of quartz,biotite,and muscovite from diff erent ore veins of the deposit vary between−82 and−59‰,and between 11.6 and 12.4‰,respectively,implying that the metallogenic solutions are mainly magmatic.According to the relevant research results of many isotope geologists,the fractionation degree of hydrogen isotopes increases as the depth to the Earth’s core increases,and the more diff erentiated the hydrogen isotopes are,the lower their values will be.In other words,mantle-derived solutions can have extremely low hydrogen isotope values.This means that the δD‰ value−134 of the pyrrhotite sample numbered SD-34 in this article may indicate mantle-derived oreforming fl uid of the deposit.The formation of the Dashuigou tellurium deposit occurred between 91.71 and 80.19 Ma. 展开更多
关键词 Carbon oxygen and hydrogen isotopes origin Independent tellurium deposit the Qinghai–Xizang Plateau
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The telomere-to-telomere genome of Fragaria vesca reveals the genomic evolution of Fragaria and the origin of cultivated octoploid strawberry 被引量:10
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作者 Yuhan Zhou Jinsong Xiong +10 位作者 Ziqiang Shu Chao Dong Tingting Gu Pengchuan Sun Shuang He Mian Jiang Zhiqiang Xia Jiayu Xue Wasi Ullah Khan Fei Chen Zong-Ming Cheng 《Horticulture Research》 SCIE CSCD 2023年第4期101-109,共9页
Fragaria vesca,commonly known as wild or woodland strawberry,is the most widely distributed diploid Fragaria species and is native to Europe and Asia.Because of its small plant size,low heterozygosity,and relative eas... Fragaria vesca,commonly known as wild or woodland strawberry,is the most widely distributed diploid Fragaria species and is native to Europe and Asia.Because of its small plant size,low heterozygosity,and relative ease of genetic transformation,F.vesca has been a model plant for fruit research since the publication of its Illumina-based genome in 2011.However,its genomic contribution to octoploid cultivated strawberry remains a long-standing question.Here,we de novo assembled and annotated a telomere-to-telomere,gap-free genome of F.vesca‘Hawaii 4’,with all seven chromosomes assembled into single contigs,providing the highest completeness and assembly quality to date.The gap-free genome is 220785082 bp in length and encodes 36173 protein-coding gene models,including 1153 newly annotated genes.All 14 telomeres and seven centromeres were annotated within the seven chromosomes.Among the three previously recognized wild diploid strawberry ancestors,F.vesca,F.iinumae,and F.viridis,phylogenomic analysis showed that F.vesca and F.viridis are the ancestors of the cultivated octoploid strawberry F.×ananassa,and F.vesca is its closest relative.Three subgenomes of F.×ananassa belong to the F.vesca group,and one is sister to F.viridis.We anticipate that this high-quality,telomere-to-telomere,gap-free F.vesca genome,combined with our phylogenomic inference of the origin of cultivated strawberry,will provide insight into the genomic evolution of Fragaria and facilitate strawberry genetics and molecular breeding. 展开更多
关键词 STRAW FRAGARIA origin
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Dose reconstruction with Compton camera during proton therapy via subset-driven origin ensemble and double evolutionary algorithm 被引量:1
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作者 Zhi-Yang Yao Yong-Shun Xiao Ji-Zhong Zhao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第4期135-148,共14页
Compton camera-based prompt gamma(PG) imaging has been proposed for range verification during proton therapy. However, a deviation between the PG and dose distributions, as well as the difference between the reconstru... Compton camera-based prompt gamma(PG) imaging has been proposed for range verification during proton therapy. However, a deviation between the PG and dose distributions, as well as the difference between the reconstructed PG and exact values, limit the effectiveness of the approach in accurate range monitoring during clinical applications. The aim of the study was to realize a PG-based dose reconstruction with a Compton camera, thereby further improving the prediction accuracy of in vivo range verification and providing a novel method for beam monitoring during proton therapy. In this paper, we present an approach based on a subset-driven origin ensemble with resolution recovery and a double evolutionary algorithm to reconstruct the dose depth profile(DDP) from the gamma events obtained by a cadmium-zinc-telluride Compton camera with limited position and energy resolution. Simulations of proton pencil beams with clinical particle rate irradiating phantoms made of different materials and the CT-based thoracic phantom were used to evaluate the feasibility of the proposed method. The results show that for the monoenergetic proton pencil beam irradiating homogeneous-material box phantom,the accuracy of the reconstructed DDP was within 0.3 mm for range prediction and within 5.2% for dose prediction. In particular, for 1.6-Gy irradiation in the therapy simulation of thoracic tumors, the range deviation of the reconstructed spreadout Bragg peak was within 0.8 mm, and the relative dose deviation in the peak area was less than 7% compared to the exact values. The results demonstrate the potential and feasibility of the proposed method in future Compton-based accurate dose reconstruction and range verification during proton therapy. 展开更多
关键词 Prompt gamma imaging Dose reconstruction Range verification origin ensemble Compton camera Evolutionary algorithm
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Correction:Geochronology and origin of Paleoproterozoic charnockites with old crustal signature in the Haisyn block of the Ukrainian shield
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《Acta Geochimica》 EI CAS CSCD 2023年第3期583-583,共1页
In the original publication of the article,Pbr should be replaced with Pb in Table 2.The correct Table 2 is provided in this article.
关键词 CRUSTAL origin Paleo
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Origin软件在“微生物学”实验教学中的应用——以细菌生长曲线的测定实验为例
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作者 郭佳 唐雅丽 +1 位作者 雷腊梅 许德麟 《教育教学论坛》 2024年第11期21-24,共4页
针对高校本科“微生物学”实验教学中遇到的数据处理问题,以细菌生长曲线测定的实验为例,使用Origin 2022软件进行数据导入、数据计算、图形绘制及插入误差棒等操作,完成细菌生长曲线的绘制。结果表明,利用Origin软件可以快速对实验数... 针对高校本科“微生物学”实验教学中遇到的数据处理问题,以细菌生长曲线测定的实验为例,使用Origin 2022软件进行数据导入、数据计算、图形绘制及插入误差棒等操作,完成细菌生长曲线的绘制。结果表明,利用Origin软件可以快速对实验数据进行批量处理,操作简捷并可避免人工计算的误差,对实验得到的非线性数据通过软件可以拟合出美观的图形,将实验结果可视化。在教学中通过引入Origin软件,可以在讲授具体微生物知识的同时,让本科生掌握一款专业的数据分析处理软件,有助于培养本科生的数据处理能力,提高综合科研素养,为后续实验课程和科研工作的数据处理工作打好基础。 展开更多
关键词 微生物学实验 origin 数据处理 生长曲线 实验教学改革
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Overpressure origins and evolution in deep-buried strata:A case study of the Jurassic Formation,central Junggar Basin,western China
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作者 Qiao-Chu Wang Dong-Xia Chen +7 位作者 Xian-Zhi Gao Mei-Jun Li Xue-Bin Shi Fu-Wei Wang Si-Yuan Chang Dong-Sheng Yao Sha Li Shu-Min Chen 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1429-1445,共17页
Overpressure is significant to the exploration and exploitation of petroleum due to its influence on hydrocarbon accumulation and drilling strategies.The deep-burial hydrocarbon reservoirs of Jurassic strata in the ce... Overpressure is significant to the exploration and exploitation of petroleum due to its influence on hydrocarbon accumulation and drilling strategies.The deep-burial hydrocarbon reservoirs of Jurassic strata in the central Junggar Basin are characterized by intensive overpressure,whose origins are complex and still unclear.In this study,Bowers'method and sonic velocity-density crossplot method based on well logging data were used as a combination for overpressure judgements in geophysics.Furthermore,the corresponding geological processes were analysed in quality and quantity to provide a rational comprehension of the overpressure origins and the model of overpressure evolution and hy-drocarbon accumulation processes.The results showed that hydrocarbon generation in the Jurassic source rocks led to overpressure in the mudstones,while hydrocarbon generation in Permian source rocks led to overpressure in the sandstone reservoirs in Jurassic strata by vertical pressure transfer.The burial and thermal history indicated that the aquathermal effect of pore fluids by temperature increase in deep strata is also an important origin of overpressure,while disequilibrium compaction may not be the dominant cause for the overpressure in deep-buried strata.Furthermore,the continuous tectonic compression in both the north-south and west-east trends from the Jurassic period to the present may also have enhanced the overpressure in deep strata.Meanwhile,the developed faults formed by intensive tectonic compression led to pressure transfer from source rocks to the Jurassic reservoirs.Overpressured geofluids with hydrocarbons migrated to sandstone reservoirs and aggravated the over-pressure in the Jurassic strata.To conclude,the intensive overpressure in the central Junggar Basin is attributed to the combination of multiple mechanisms,including hydrocarbon generation,the aqua-thermal effect,tectonic compression and pressure transfer.Furthermore,the developed overpressure indicated hydrocarbon migration and accumulation processes and the potential of oil and gas reservoirs in deeply buried strata.We hope this study will provide a systematic research concept for overpressure origin analysis and provide guidance for petroleum exploration and exploitation in deep-buried strata. 展开更多
关键词 origin of overpressure Hydrocarbon generation Tectonic compression Overpressure transfer Junggar Basin
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Textual Research on Name, Variety and Property of the Multi-origin Tibetan Herb "Azhong"
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作者 Zhuomacuomao Suolanglazong Cairangnanjia 《Agricultural Biotechnology》 CAS 2023年第4期52-57,共6页
By consulting ancient Tibetan medical literature such as books of materia medica,medical works,and prescription books,as well as modern and contemporary literature and materials,and in combination with the interview a... By consulting ancient Tibetan medical literature such as books of materia medica,medical works,and prescription books,as well as modern and contemporary literature and materials,and in combination with the interview and investigation of clinical use and expert consultation,we collated and verified the name,variety classification,plant origin,application and other recorded information of Tibetan herb"Azhong",and summarized and analyzed the phenomenon of mixed use or substitution of medicinal plants.According to textual research,it first appeared in the Four Medical Tantras.The Tibetan herb"Azhong"is simply recorded in the ancient books and Materia Medica,which are collectively called"Azhong".Since the 15 th century,there have been varieties such as Za Azhong,Kan Azhong,Xing Azhong,Pumou Azhong,Zha Azhong,Bang Azhong,and the top grade is called Azhong Nabu and Nacang Azhong,and the bottom grade is Azhong Gabu.According to modern literature,the origin of"Azhong"involves 12 species of plants belonging to 8 genera,5 families.At present,Arenaria kansuensis Maxim,Ajania purpurea Shih.and Thalictrum squamiferum Lecoy are the mainstream medicinal materials of"Azhong".There is a certain basis for clinical application and theoretical records in the literature in terms of the mutual alternative use of Tibetan medicinal materials such as"Azhong"and traditional medicinal materials in different regions.Therefore,it is necessary to use modern chemical technology and pharmacological experiments to conduct a comparative study on the material basis and biological activity of different varieties of medicinal materials,and carry out a survey on resources and use status,so as to standardize the use of their varieties and origins and improve the safety of clinical medication. 展开更多
关键词 Tibetan medicine Azhong origin Drug property
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The Origin and Preservation of Suspended Barites near the 90°E Ridge in the Northeastern Indian Ocean
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作者 BU Xuejiao LIU Ming +5 位作者 DING Yi YANG Yadi HUANG Mu SUN Xiaoxia FAN Dejiang YANG Zuosheng 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第1期88-98,共11页
Suspended particulate barite crystals were detected in the water columns at four different stations near the 90°E ridge in the Indian Ocean.Four distinct morphological types of marine barites were distinguished:e... Suspended particulate barite crystals were detected in the water columns at four different stations near the 90°E ridge in the Indian Ocean.Four distinct morphological types of marine barites were distinguished:euhedral-subhedral crystals,oval or round crystals,rhombic crystals,and irregular crystals.The barite crystals in the study area are typically fine,with a dominant size of 1–3μm.The vertical distribution of barites is significantly affected by the formation and sedimentation processes.Barites begin to appear at a depth of 30 m and are formed primarily from the surface to the depth of 2000m with a concentration peak at the depth of 200m,where particles are coarser than those in the other layers.The barites begin to settle and dissolve once formed in the water column,resulting in finer barite particles and lower particle concentrations.The formation of barite crystals is related to biological processes associated with the decomposition of barium-rich skeletons in the microenvironment of decaying organic matter that is affected by the primary productivity and dissolved oxygen content in the water column.The dissolving process of barite crystals showed similar variation with the concentration of dissolved barium in ocean water,and the substitution of strontium for barite in crystals promotes the selective dissolution of barite and exerts an important impact on its morphology.It is approximately 33%of barites in the amount and 22%in the concentration to settle to the bottom of the water column compared to that observed in the main barite formation zone. 展开更多
关键词 marine barite Indian Ocean origin and sedimentation process dissolution and preservation
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A Study on the Origin and Binding Form of Printing Edition of Qing Guangxu’s“Shanxi Tongzhi”
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作者 LI Lei 《Journal of Literature and Art Studies》 2023年第1期36-46,共11页
Shanxi Tongzhi,written during the reign of Emperor Guangxu in the Qing Dynasty,is a typical example of the printed version of ancient Chinese books.Through the textual research of relevant cultural and historical mate... Shanxi Tongzhi,written during the reign of Emperor Guangxu in the Qing Dynasty,is a typical example of the printed version of ancient Chinese books.Through the textual research of relevant cultural and historical materials,combined with the research on the publishing background and the formal binding system,this paper shows that“Shanxi Tongzhi”during Qing Guangxu has four editions since the original edition was compiled and published in 1892.With development and changes,its content has been continuously deepened and expanded.The version inherits the ancient system and extensive collection,the printing form is rigorous,and the binding is simple and exquisite,which has essential historical research value.At the same time,the traditional and straightforward Chinese-style aesthetics of the ancient printed version of“Shanxi Tongzhi”published during Qing Guangxu has a very high reference value for the exploration and development of the new connotation of the modern book form. 展开更多
关键词 Shanxi Tongzhi original printed edition version origin binding form
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Petroleum geochemistry and origin of shallow-buried saline lacustrine oils in the slope zone of the Mahu sag, Junggar Basin, NW China
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作者 Dong-Yong Wang Mei-Jun Li +6 位作者 Yang Zhou Lu Yang Yuan-Feng Yang Er-Ting Li Jun Jin Xian-Li Zou Bo-Dong Xu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3363-3378,共16页
Recently, significant oil discoveries have been made in the shallower pay zones of the Jurassic Badaowan Formation (J_(1)b) in the Mahu Sag, Junggar Basin, Northwest China. However, little work has been done on the ge... Recently, significant oil discoveries have been made in the shallower pay zones of the Jurassic Badaowan Formation (J_(1)b) in the Mahu Sag, Junggar Basin, Northwest China. However, little work has been done on the geochemical characteristics and origins of the oil in the J_(1)b reservoir. This study analyzes 44 oil and 14 source rock samples from the area in order to reveal their organic geochemical characteristics and the origins of the oils. The J_(1)b oils are characterized by a low Pr/Ph ratio and high β-carotene and gammacerane indices, which indicate that they were mainly generated from source rocks deposited in a hypersaline environment. The oils are also extremely enhanced in C_(29) regular steranes, possibly derived from halophilic algae. Oil-source correlation shows that the oils were derived from the Lower Permian Fengcheng Formation (P_(1)f) source rocks, which were deposited in a strongly stratified and highly saline water column with a predominance of algal/bacterial input in the organic matter. The source rocks of the Middle Permian lower-Wuerhe Formation (P_(2)w), which were deposited in fresh to slightly saline water conditions with a greater input of terrigenous organic matter, make only a minor contribution to the J_(1)b oils. The reconstruction of the oil accumulation process shows that the J_(1)b oil reservoir may have been twice charged during Late Jurassic–Early Cretaceous and the Paleogene–Neogene, respectively. A large amount volume of hydrocarbons generated in the P_(1)f source rock and leaked from T_(1)b oil reservoirs migrated along faults connecting source beds and shallow-buried secondary faults into Jurassic traps, resulting in large-scale accumulations in J_(1)b. These results are crucial for understanding the petroleum system of the Mahu Sag and will provide valuable guidance for petroleum exploration in the shallower formations in the slope area of the sag. 展开更多
关键词 Molecular marker Saline lacustrine oil Petroleum origin Lower Permian Fengcheng Formation Shallow-buried reservoir Mahu Sag
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Origin of hydrocarbon fluids and discussion of abnormal carbon isotopic compositions in the Lishui-Jiaojiang Sag,East China Sea Shelf Basin
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作者 Jingqi Xu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第3期76-88,共13页
The hydrocarbon gases in the L1 gas field of the Lishui-Jiaojiang Sag have been commonly interpreted to be an accumulation of pure sapropelic-type thermogenic gas.In this study,chemical components,stable isotopic comp... The hydrocarbon gases in the L1 gas field of the Lishui-Jiaojiang Sag have been commonly interpreted to be an accumulation of pure sapropelic-type thermogenic gas.In this study,chemical components,stable isotopic compositions,and light hydrocarbons were utilized to shed light on the origins of the hydrocarbon fluids in the L1gas pool.The hydrocarbon fluids in the L1 gas pool are proposed to be a mixture of three unique components:mid-maturity oil from the middle Paleocene coastal marine Lingfeng source rock,oil-associated(late oil window)gas generated from the lower Paleocene lacustrine Yueguifeng source rock,and primary microbial gas from the paralic deposits of the upper Paleocene Mingyuefeng source rock.Here,for the first time,the hydrocarbon gases in the L1 gas pool are diagnosed as mixed oil-associated sapropelic-type gas and microbial gas via four pieces of principal evidence:(1)The abnormal carbon isotopic distributions of all methane homologues from C_(1)(CH_(4)or methane)to C_(5)(C_(5)H_(12)or pentane)shown in the Chung plot;(2)the diagnostic~(13)C-depleted C_(1)compared with the thermogenic sapropelic-type gas model,whileδ^(13)C_(2)(C_(2)H_(6)or ethane)andδ^(13)C_(3)(C_(3)H_(8)or propane)both fit perfectly;(3)the excellent agreement of the calculated carbon isotopic compositions of the pure thermogenic gas with the results of the thermal simulated gas from the type-II1 kerogen-rich Yueguifeng source rock;and(4)the oil-associated gas inferred from various binary genetic diagrams with an abnormally elevated gas oil ratio.Overall,the natural gases of the L1 gas pool were quantified in this study to comprise approximately 13%microbial gas,nearly 48%oil-associated sapropelic-type gas,and 39%of nonhydrocarbon gas.The microbial gas is interpreted to have been codeposited and entrained in the humic-kerogen-rich Mingyuefeng Formation under favorable lowtemperature conditions during the late Paleocene-middle Eocene.The microbial gas subsequently leaked into the structurally and stratigraphically complex L1 trap with oil-associated sapropelic-type gas from the Yueguifeng source rock during the late Eocene-Oligocene uplifting event.A small amount of humic-kerogen-generated oil in the L1 gas pool is most likely to be derived from the underlying Lingfeng source rock.The detailed geological and geochemical considerations of source rocks are discussed to explain the accumulation history of hydrocarbon fluids in the L1 gas pool.This paper,therefore,represents an effort to increase the awareness of the pitfalls of various genetic diagrams,and an integrated geochemical and geological approach is required for hydrocarbonsource correlation. 展开更多
关键词 origin of hydrocarbons carbon isotope hydrogen isotope light hydrocarbon East China Sea Shelf Basin Lishui-Jiaojiang Sag
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Hongshan Culture:Tracing The Origins of Chinese Civilization
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《China Report ASEAN》 2023年第8期36-37,共2页
The Liaohe River basin in northeastern China occupies an important geographical position connecting Northeast Asia and the Central Plains.Millennia ago,it witnessed the convergence of farming,fishing,hunting,and nomad... The Liaohe River basin in northeastern China occupies an important geographical position connecting Northeast Asia and the Central Plains.Millennia ago,it witnessed the convergence of farming,fishing,hunting,and nomadic cultures and the coexistence and flourishing of multiple peoples.Archaeological excavations and research on this area show that as early as the Neolithic period,the indigenous Hongshan Culture had already embraced the dawn of civilization.Traces of early city forms were discovered at the Niuheliang site dating from the late Hongshan period,providing archaeological evidence on the 5,000 years of history of Chinese civilization.In academic circles,Hongshan Culture is considered the“tap root”of Chinese civilization,from which the core traditions of Chinese civilization such as respecting heaven and ancestors and worshiping the dragon and jade originated.This issue’s“Focus”section is dedicated to tracing the origins of Chinese civilization by focusing on the origins and characteristics of Hongshan Culture as well as its fusion with other civilizations around the world.We hope to shed light on the far reaching,time-honored Chinese culture and provide a fresh perspective for readers to understand the development of human civilization. 展开更多
关键词 connecting originated DRAGON
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Cultural and Historical Origins of the Central Axis of Beijing
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作者 ZHANG HUI 《China Today》 2023年第1期24-27,共4页
The Central Axis of Beijing embodies the cultural spirit and urban planning ingenuity of an ancient nation.WITH the release of the Beijing Central Axis panoramic map by Beijing Municipal Cultural Heritage Bureau in la... The Central Axis of Beijing embodies the cultural spirit and urban planning ingenuity of an ancient nation.WITH the release of the Beijing Central Axis panoramic map by Beijing Municipal Cultural Heritage Bureau in late November,2022,together with the plan for its protection and management in the coming decade. 展开更多
关键词 CENTRAL AXIS origin
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Origin of dolomites in the Permian dolomitic reservoirs of Fengcheng Formation in Mahu Sag,Junggar Basin, NW China
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作者 TANG Yong LYU Zhengxiang +7 位作者 HE Wenjun QING Yuanhua LI Xiang SONG Xiuzhang YANG Sen CAO Qinming QIAN Yongxin ZHAO Xinmei 《Petroleum Exploration and Development》 2023年第1期43-56,共14页
Origin of authigenic dolomites in the dolomitic reservoir of the Permian Fengcheng Formation in the Mahu Sag of Junggar Basin is unclear.Occurrence and genetic evolution of the authigenic dolomites in dolomitic rock r... Origin of authigenic dolomites in the dolomitic reservoir of the Permian Fengcheng Formation in the Mahu Sag of Junggar Basin is unclear.Occurrence and genetic evolution of the authigenic dolomites in dolomitic rock reservoir of the Fengcheng Formation in the Mahu Sag were analyzed by polarized and fluorescence thin sections,scanning electron microscope(SEM),electron microprobe(EMP),C,O and Sr isotopes analysis,and other techniques.(1)Dolomites were mainly precipitated in three stages:penecontemporaneous-shallow burial stage(early stage of the Middle Permian),middle burial stage(middle stage of the Middle Permian),and middle-deep burial stage,with the former two stages in dominance.(2)Dolomitization fluid was high-salinity brine originating from alkaline lake.In the penecontemporaneous-shallow burial stage,Mg^(2+)was mainly supplied by alkaline-lake fluid and devitrification of volcanic glass.In the middle burial stage,Mg^(2+)mainly came from the transformation of clay minerals,devitrification of volcanic glass and dissolution of aluminosilicates such as feldspar.(3)Regular changes of Mg,Mn,Fe,Sr,Si and other elements during the growth of dolomite were mainly related to the alkaline-lake fluid,and to different influences of devitrification and diagenetic alteration of volcanic materials during the burial.(4)In the penecontemporaneous stage,induced by alkaline-lake microorganisms,the micritic-microcrystalline dolomites were formed by primary precipitation,replacement of aragonite and high-Mg calcite,and other processes;in the shallow burial stage,the silt-sized dolomites were formed by continuous growth of micritic-microcrystalline dolomite and replacement of calcites,tuffs and other substances;in the middle burial stage,the dolomites,mainly silt-and fine-sized,were formed by replacement of volcanic materials.The research results are referential for investigating the formation mechanism and distribution patterns of tight dolomitic reservoirs in the Mahu Sag and other similar oil and gas bearing areas. 展开更多
关键词 dolomitic rock dolomite origin tight oil reservoir Permian Fengcheng Formation Mahu Sag Junggar Basin fluid source fluid evolution isotopic composition
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Theory of the Origin of Terrestrial and Lunar Ores
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作者 Alexander N. Safronov 《International Journal of Geosciences》 2023年第6期547-583,共37页
In this study, the theory of ore formation on the Earth and the Moon was developed. It is shown that ore deposits on the Earth and the Moon were mainly formed simultaneously with the separation of the Moon from the pr... In this study, the theory of ore formation on the Earth and the Moon was developed. It is shown that ore deposits on the Earth and the Moon were mainly formed simultaneously with the separation of the Moon from the protoplanet and the formation of the oldest continents. The formation of terrestrial ores occurred as a result of the release of intermediate and heavy chemical elements from the deep layers of the protoplanet and the subsequent process of adhesion to old terrestrial geological faults. The time of terrestrial and lunar ores formations corresponds to the boundary between the Tonian and Cryogenian Periods (~720 Ma). Lunar ore formation processes are different on the near and far sides. The farside of the Moon is a single piece of the protoplanetary lithosphere, so ores there could be formed mainly due to the overflow of igneous rocks over the edge of the lunar continent. On the nearside, due to the rapid cooling, ores were formed in the area of navel-string during the drip-liquid separation of the Moon from the Earth. Due to the fact that the Moon separated at the first stage, the amount of water and methane on it is limited. In periods after the Cryogenian, volcanic, lava and sedimentary rocks on Earth could be enriched with intermediate elements due to the disruption of vertical stratification during galactic storms. To analyze this, a comparison of terrestrial volcanic and lunar pseudo-volcanic activity was carried out in the work. 展开更多
关键词 Comet Impact Galaxy Storm Galaxy Calm Elemental Buoyancy theory Mantle-Core Layers Ores origin
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Origin, Creation, and Splitting of the Electron
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作者 Arlen Young 《Journal of Modern Physics》 2023年第12期1563-1577,共15页
The author’s earlier papers proposed a model of the electron’s internal structure comprised of both positive and negative masses and charges. Their relation to the fine structure constant a was calculated in the aut... The author’s earlier papers proposed a model of the electron’s internal structure comprised of both positive and negative masses and charges. Their relation to the fine structure constant a was calculated in the author’s previous paper. In this paper, more details of the model of the electron’s internal structure, in particular the thicknesses of its outer shell mass and charge, are calculated. Magnetostriction of the electron’s surface is generated by the electron’s spinning surface charge. It is calculated that this magnetostriction holds the electron together, counterbalancing the outward electrical and centrifugal forces. The results of these calculations enable the prediction that a sufficiently strong external magnetic field can split the electron into three equal pieces. The field strength would have to be on the order of at least 8% of the strength at the center of the electron. A model for the origin and creation of an electron from a gamma ray wave is proposed. Evidence is presented that, for certain transitions, mass might be quantized and that the quantum of mass would be 1/2a times the electron mass. 展开更多
关键词 Mass Quantization Electron Fractionalization Splitting the Electron Electron origin Electron Creation Electron Magnetostriction Electron Charge Inconsistency Electron Mass Inconsistency
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Identification of S-RNase genotype and analysis of its origin and evolutionary patterns in Malus plants
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作者 Zhao Liu Yuan Gao +10 位作者 Kun Wang Jianrong Feng Simiao Sun Xiang Lu Lin Wang Wen Tian Guangyi Wang Zichen Li Qingshan Li Lianwen Li Dajiang Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1205-1221,共17页
Identification of the S genotype of Malus plants will greatly promote the discovery of new genes,the cultivation and production of apple,the breeding of new varieties,and the origin and evolution of self-incompatibili... Identification of the S genotype of Malus plants will greatly promote the discovery of new genes,the cultivation and production of apple,the breeding of new varieties,and the origin and evolution of self-incompatibility in Malus plants.In this experiment,88 Malus germplasm resources,such as Aihuahong,Xishuhaitang,and Reguanzi,were used as materials.Seven gene-specific primer combinations were used in the genotype identification.PCR amplification using leaf DNA produced a single S-RNase gene fragment in all materials.The results revealed that 70 of the identified materials obtained a complete S-RNase genotype,while only one S-RNase gene was found in 18 of them.Through homology comparison and analysis,13 S-RNase genotypes were obtained:S_(1)S_(2)(Aihuahong,etc.),S_(1)S_(28)(Xixian Haitang,etc.),S_(1)S_(51)(Hebei Pingdinghaitang),S_(1)S_(3)(Xiangyangcun Daguo,etc.),S_(2)S_(3)(Zhaiyehaitang,etc.),S_(3)S_(51)(Xishan 1),S_(3)S_(28)(Huangselihaerde,etc.),S_(2)S_(28)(Honghaitang,etc.),S_(4)S_(28)(Bo 11),S_(7)S_(28)(Jiuquan Shaguo),S_(10)S_e(Dongchengguan 13),S_(10)S_(21)(Dongxiangjiao)and S_(3)S_(51)(Xiongyue Haitang).Simultaneously,the frequency of the S gene in the tested materials was analyzed.The findings revealed that different S genes had varying frequencies in Malus resources,as well as varying frequencies between intraspecific and interspecific.S_(3) had the highest frequency of 68.18%,followed by S_(1)(42.04%).In addition,the phylogenetic tree and origin evolution analysis revealed that the S gene differentiation was completed prior to the formation of various apple species,that cultivated species also evolved new S genes,and that the S_(50) gene is the oldest S allele in Malus plants.The S_(1),S_(29),and S_(33) genes in apple-cultivated species,on the other hand,may have originated in M.sieversii,M.hupehensis,and M.kansuensis,respectively.In addition to M.sieversii,M.kansuensis and M.sikkimensis may have also played a role in the origin and evolution of some Chinese apples. 展开更多
关键词 MALUS S-RNase genotype SELF-INCOMPATIBILITY origin and evolution
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Annelid functional genomics reveal the origins of bilaterian life cycles
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作者 Francisco M Martín-Zamora 《四川生理科学杂志》 2023年第2期344-344,共1页
Indirect development with an intermediate larva exists in all major animal lineages1, which makes larvae central to mostscenarios of animal evolution2-11. Yet how larvae evolved remains disputed. Here we show that tem... Indirect development with an intermediate larva exists in all major animal lineages1, which makes larvae central to mostscenarios of animal evolution2-11. Yet how larvae evolved remains disputed. Here we show that temporal shifts (that is,heterochronies) in trunk formation underpin the diversification of larvae and bilaterian life cycles. We performed chromosomescalegenome sequencing in the annelid Owenia fusiformis with transcriptomic and epigenomic profiling during the life cycles ofthis and two other annelids. We found that trunk development is deferred to pre-metamorphic stages in the feeding larva of O.fusiformis but starts after gastrulation in the non-feeding larva with gradual metamorphosis of Capitella teleta and the directdeveloping embryo of Dimorphilus gyrociliatus. Accordingly, the embryos of O. fusiformis develop first into an enlarged anteriordomain that forms larval tissues and the adult head12. Notably, this also occurs in the so-called 'head larvae' of other bilaterians13-17, with which the O. fusiformis larva shows extensive transcriptomic similarities. Together, our findings suggest that the temporaldecoupling of head and trunk formation, as maximally observed in head larvae, facilitated larval evolution in Bilateria. Thisdiverges from prevailing scenarios that propose either co-option9,10 or innovation11 of gene regulatory programmes to explainlarva and adult origins. 展开更多
关键词 LARVAL LIFE origin
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Geographical origin identification of winter jujube(Ziziphus jujuba Dongzao')by using multi-element fingerprinting with chemometrics
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作者 Xiabing Kong Qiusheng Chen +8 位作者 Min Xu Yihui Liu Xiaoming Li Lingxi Han Qiang Zhang Haoliang Wan Lu Liu Xubo Zhao Jiyun Nie 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1749-1762,共14页
Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 16... Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 167 winter jujube samples from the main winter jujube producing areas of China by inductively coupled plasma mass spectrometer(ICP-MS).As a result,16 elements(Mg,K,Mn,Cu,Zn,Mo,Ba,Be,As,Se,Cd,Sb,Ce,Er,Tl,and Pb)exhibited significant differences in samples from different producing areas.Supervised linear discriminant analysis(LDA)and orthogonal projection to latent structures discriminant analysis(OPLS-DA)showed better performance in identifying the origin of samples than unsupervised principal component analysis(PCA).LDA and OPLS-DA had a mean identification accuracy of 87.84 and 94.64%in the testing set,respectively.By using the multilayer perceptron(MLP)and C5.0,the prediction accuracy of the models could reach 96.36 and 91.06%,respectively.Based on the above four chemometric methods,Cd,Tl,Mo and Se were selected as the main variables and principal markers for the origin identification of winter jujube.Overall,this study demonstrates that it is practical and precise to identify the origin of winter jujube through multi-element fingerprint analysis with chemometrics,and may also provide reference for establishing the origin traceability system of other fruits. 展开更多
关键词 winter jujube multi-element fingerprint analysis CHEMOMETRICS origin traceability
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Management of retroperitoneal high-grade serous carcinoma of unknown origin:A case report
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作者 Wen-Lin Hsieh Dah-Ching Ding 《World Journal of Clinical Cases》 SCIE 2024年第6期1190-1195,共6页
BACKGROUND Retroperitoneal high-grade serous carcinoma(HGSC)of unknown origin is a sporadic tumor that can originate from ovarian cancer.Herein,we report the case of a woman with retroperitoneal HGSC of unknown origin... BACKGROUND Retroperitoneal high-grade serous carcinoma(HGSC)of unknown origin is a sporadic tumor that can originate from ovarian cancer.Herein,we report the case of a woman with retroperitoneal HGSC of unknown origin and describe how she was diagnosed and treated.CASE SUMMARY A 71-year-old female presented with the tumor marker CA125 elevated to 1041.9 U/mL upon a regular health examination.Computed tomography revealed retroperitoneal lymph node enlargement.Subsequently,positron emission tomography scanning revealed lesions with increased F-18 fluorodeoxyglucose uptake at the nodes.As a result,she underwent laparoscopic lymph node resection,and pathology revealed metastatic adenocarcinoma with CK7(+),PAX8(+),WT1(+),PR(-),and p53 mutational loss of expression,indicating that the origin may be from the adnexa.The patient was admitted to our ward and underwent laparoscopic staging;however,the pathological results were negative.Under the suspicion of retroperitoneal HGSC of unknown origin,chemotherapy and targeted therapy were initiated.Tumor marker levels decreased after treatment.CONCLUSION We present a case of HGSC of unknown origin managed using retroperitoneal lymphadenectomy,staging surgery,chemotherapy,and targeted therapy. 展开更多
关键词 High-grade serous carcinoma RETROPERITONEUM origin Chemotherapy Lymph node Case report
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