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Reanalysis on the Spectral Characteristics and Materials of Jade Jue Unearthed from Lijiashan Ancient Tomb in Yunnan Province, China
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作者 Ting Fang Jifu Liu Mingxing Yang 《宝石和宝石学杂志(中英文)》 CAS 2024年第2期48-55,共8页
Jade ware Jue is one of the most fashionable ornament in ancient China from the Neolithic Age to the Han Dynasty.In this study,the remnants of jade ware Jue,from Lijiashan ancient tomb group have been tested and analy... Jade ware Jue is one of the most fashionable ornament in ancient China from the Neolithic Age to the Han Dynasty.In this study,the remnants of jade ware Jue,from Lijiashan ancient tomb group have been tested and analyzed respectively.The samples through a light etch surface showing glass luster and those with a severe etch surface showing earthen luster.With the aid of X-ray fluorescence Spectrometer(X-ray Fluorescence)test and X-ray diffraction(XRD)detection,the results show that tremolite is not the main mineral of the sample.The main components of the tested samples with light erosion are antigorite and talc,although the main components of the samples with severe erosion are calcite containing calcium carbonate barium.Furthermore,the research on jade ware Jue in Yunnan culture has not only contributed to our further understanding of the jade objects from Yunnan culture and the variety of jade material located in the Yunnan Province.It also provides a basis for the trace of the history and culture through the distribution and evolution of burial hierarchy laws.At the same time,the microscopic observation of the tested samples manifested a residual trace of“string”at the perforation,which has played a critical role in restoring the wearing of jade ware Jue from the tombs of the ancient Yunnan State and the handicraft skills at that time. 展开更多
关键词 Dian culture jade Jue corroded ancient jade XRD erosion mechanism yunnan China
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New and interesting diatoms from the Shimen Wetwalls,Yunnan Province,China.Ⅱ.The diatom genus Nupela Vyverman&Compère(Bacillariophyceae)
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作者 Qi LIU Xi LUO +1 位作者 Shulian XIE John Patrick KOCIOLEK 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第1期327-341,共15页
We detailed the valve morphology of five new species of diatom genus Nupela from wetwall communities in Yunnan Province,China,with light and scanning electron microscope.The five new species demonstrate great variabil... We detailed the valve morphology of five new species of diatom genus Nupela from wetwall communities in Yunnan Province,China,with light and scanning electron microscope.The five new species demonstrate great variability within the genus,as three of them are biraphid and two are monoraphid.In addition,variation was noted in the structure of internal proximal raphe ends,with some species having anchor-shaped ends and other species have hooked ends.The genus Nupela has grown considerably in 30years since it was first proposed,going from a monotypic genus to over 85 taxa.Diagnosis of the genus is based on the presence of an external covering over the areolae.We discussed the systematic placement of Nupela within the naviculoid diatoms.Yunnan Province appears to harbor many endemic diatom taxa,and many regions of the province have yet to be studied. 展开更多
关键词 Nupela scanning electron microscope(SEM) yunnan new species morphology China BACILLARIOPHYCEAE
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Epidemiological survey of cystic echinococcosis in southwest China:From the Qinghai-Tibet plateau to the area of Yunnan
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作者 Jin-Rong Zi Dan Xiao +8 位作者 Jia Peng Fang-Wei Wu Jian-Xiong Li Xin-Liu Yan Zheng-Qing Wang Xuan Cai Qian Xu Ben-Fu Li Ya-Ming Yang 《World Journal of Hepatology》 2024年第2期229-240,共12页
BACKGROUND Echinococcosis is prevalent in 9 provinces in Western and Northern China.An epidemiological survey of echinococcosis in 2012 and 2016 showed cases of echinococcosis in Yunnan Province.AIM To understand the ... BACKGROUND Echinococcosis is prevalent in 9 provinces in Western and Northern China.An epidemiological survey of echinococcosis in 2012 and 2016 showed cases of echinococcosis in Yunnan Province.AIM To understand the spatial distribution and epidemiological characteristics of echinococcosis in Yunnan for the prevention and control of echinococcosis and to reduce the risk of infection in Yunnan Province.METHODS Based on the China Information System for Disease Control and Prevention(CISDCP),echinococcosis cases reported from 36 hospitals and 34 Centers for Disease Control were investigated and epidemiologically analyzed from 2021 to 2022.The exclusion criteria included suspected cases,same case only counted once and cases not from Yunnan.A total of 705 cases were investigated,of which 397 cases were suitable for statistical analysis.In these 397 cases,epidemiological investigation was tracked in 187 cases.All data were inputted using double entry in the Excel database,with error correction by double-entry comparison.The data on echinococcosis cases in Yunnan Province were analyzed by ArcGIS 10.1 software to generate a density map of echinococcosis distribution.All statistical analyses were conducted using SPSS 17.0,including the chi-square test,linear regression test and logistic univariate and multivariate regression analyses.RESULTS A total of 397 cases were found in 89 counties in Yunnan Province.The number of cases in the top three prefectures were Dali(38.1%),Diqing(10.1%),and Kunming(8.3%),and the top five counties were Jianchuan(9.1%),Shangri La(8.3%),Eryuan(7.6%),Heqing(6.9%),and Dali Districts(5.0%).There were significant differences between the different areas.The case reporting rate by CISDCP(33.8%)was low;the first case was reported by CISDCP in 2002,and the highest number of cases was 50(2017).Confirmed and clinical cases accounted for 62.5%and 37.5%,respectively.However,90.9%of the cases of hydatid disease were reported by the hospital system,and only 9.1%of the cases of hydatid disease were found in the community through active screening.The difference between the two methods of case detection was statistically significant.Most of the cases of echinococcosis were found in farmers/herdsmen(75.1%)and students(9.1%).In addition,Han(43.6%)and Bai(26.2%)had a higher incidence of infection than other nationalities,and the liver(87.7%)and lung(6.8%)were the most common sites of cyst formation.Among the analyzed cases,187 were epidemiologically analyzed and the clinical symptoms were not obvious in the early stage in 47.1%of cases.The results of logistic regression analysis showed that the age group,education level,presence of dogs in the family(either previously or currently),and handwashing(occasionally or not)were factors related to echinococcosis infection.55.6%of cases were in endemic areas,and 44.4%of cases were in non-endemic areas.Among 83 cases in non-endemic areas,only 4 cases had been to endemic areas and had a history of living,working,travelling,or hunting in echinococcosis epidemic areas.CONCLUSION Cases of echinococcosis were reported throughout the entire Yunnan province,with the majority distributed in Western Yunnan,suggesting that echinococcosis control should be strengthened in this area.We suggest that an epidemiological investigation should be carried out in the future,based on the clues from newly discovered cases in hospitals or from the CISDCP.The newly discovered cases in the hospital provided clues to comprehensively determine the location of cases and where epidemic spot investigation should be conducted. 展开更多
关键词 ECHINOCOCCOSIS CASES Epidemiological analysis yunnan province
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Geology and Geochemistry of K-feldspar Veins in Lamprophyre at the Zhenyuan Gold Deposit,Yunnan,Southwest China:Implications for Gold Mineralization
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作者 ZHANG Huichao CHAI Peng +2 位作者 ZHANG Hongrui ZHOU Limin HOU Zengqian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期104-116,共13页
Lamprophyres typically appear in hydrothermal gold deposits.The relationship between lamprophyres and gold deposits is investigated widely.Some researchers suggest that the emplacement of lamprophyres triggers gold mi... Lamprophyres typically appear in hydrothermal gold deposits.The relationship between lamprophyres and gold deposits is investigated widely.Some researchers suggest that the emplacement of lamprophyres triggers gold mineralization,whereas others hypothesize that the formation of lamprophyres increases the fertility of mantle sources and ore-forming fluids.K-feldspar veins,with ages between those of lamprophyres and gold deposits,appear in lamprophyres in Zhenyuan.Therefore,K-feldspar veins are ideal for investigating the relationship between lamprophyres and gold deposits.Phlogopite in K-feldspar veins has lower Mg#,Ni,and Cr contents and higher TiO2,Li,Ba,Sr,Sc,Zr,Nb,and Cs contents than phlogopite in lamprophyres.The in-situ Sr isotopic values of apatites(0.7063–0.7066)in K-feldspar veins are within the range for apatites(0.7064–0.7078)from lamprophyres.High large-ion lithophile element concentrations and low Nb and Ta concentrations in phlogopite from lamprophyres,in addition to high(87Sr/86Sr)i values of apatite(0.7064–0.7078),indicate that the magma parental to these phlogopite and apatite crystals is derived from an enriched mantle.Kfeldspar veins are genetically correlated with lamprophyres,whereas sulfide mineral assemblage and trace element compositions of pyrite in K-feldspar veins suggest that K-feldspar veins in lamprophyres are not directly related to gold mineralization of the Zhenyuan deposit. 展开更多
关键词 LAMPROPHYRE K-feldspar vein apatite Sr isotope gold Zhenyuan deposit yunnan
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Geological characterization and exploration potential of shale gas in the Carboniferous Jiusi Formation,northern Guizhou and Yunnan provinces,SW China
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作者 Weiming Feng Rong Li +3 位作者 Zhan Zhao Qian Yu Wei Liu Junfeng Cao 《Energy Geoscience》 2023年第3期169-181,共13页
Dark mudstones and shales of the Carboniferous Jiusi Formation are widely developed in northern Guizhou and Yunnan provinces, SW China. However, the distribution, reservoir characterization, and exploration potential ... Dark mudstones and shales of the Carboniferous Jiusi Formation are widely developed in northern Guizhou and Yunnan provinces, SW China. However, the distribution, reservoir characterization, and exploration potential of organic-rich shales in this area are yet to be quantified, thus limiting the prospect of shale gas in this area. This study investigates the basic geological conditions of Jiusi shale gas, using core data, well-logs, and some other test data, obtaining the following results. The organic-rich shales are mainly composed of deltaic-to-shallow-shelf deposits, with thickness ranging from 0 to 450 m, and above 350 m around the subsidence center. The organic matter is mainly type Ⅱ kerogen with TOC content of mostly 1%–2%, indicating a moderate maturity. The argillaceous shale reservoirs are indicative of strong heterogeneity, high clay minerals content, low porosity, low permeability, high specific surface area, and relatively developed secondary porosity. The gas-log anomaly intervals obtained from the survey wells have a cumulative thickness that is apparently greater than 200 m, and a few shale intervals showing high desorbed and adsorbed gas contents. Due to complex structures in the study area, conditions responsible for shale gas occurrence and trapping are generally moderate. However, areas having wide and gentle folds with moderate depth of burial reveals relatively favorable conditions of hydrocarbon traps. In contrast with typical marine-continental transitional shales, the Jiusi shale have better geological conditions for shale gas preservation. The analysis of the geological framework and hydrocarbon potential of Carboniferous Jiusi Formation provide more insight for the exploration of Carboniferous shale gas in southern China. 展开更多
关键词 Marine-continental tansitional fades 0rganic-nich shale Shale gas Exploration potential CARBONIFEROUS Northem border area between Guizhou and yunnan China
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A Brief Discussion on the Development of the Silk-Weaving Industry Along the “Southern Silk Road” in Yunnan
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作者 Lin Kaiqiang 《Contemporary Social Sciences》 2024年第1期18-33,共16页
Ancient Yunnan was one of the most significant regions along China’s ancient“Southern Silk Road.”During the Nanzhao period(738–902)of the late Tang Dynasty,Yunnan’s silk-weaving industry underwent a qualitative l... Ancient Yunnan was one of the most significant regions along China’s ancient“Southern Silk Road.”During the Nanzhao period(738–902)of the late Tang Dynasty,Yunnan’s silk-weaving industry underwent a qualitative leap as skilled silk craftsmen from the Bashu area migrated to Yunnan and introduced mulberry planting,silkworm breeding,and advanced silk-weaving techniques from Sichuan to the region.Consequently,people in Yunnan gradually acquired expertise in brocade weaving and embroidery.Many even mastered complex silk-weaving techniques.The development and progress of the silk-weaving industry in the ancient Yunnan region were intricately linked to the economic function and value of silk as both a commodity and currency along the“Southern Silk Road.”The local government in ancient Yunnan was greatly motivated by the economic interests brought by the development of silk-related industries and recognized the significance of developing the local silk industry.They even initiated a campaign to capture skilled silk craftsmen from Sichuan,aiming to foster the growth of the silk-weaving industry in Yunnan.After years of dedicated efforts from the local government in ancient Yunnan,the region emerged as a significant hub for silk production along China’s ancient“Southern Silk Road.”Despite the devastation caused by the wars in other parts of the country,Yunnan’s silk industry continued to thrive and provide ample silk products to sustain trade along this renowned route.In the contemporary era,amidst the decline of the silk-weaving industry in eastern China,Yunnan has proposed an industrial development strategy known as“relocating the silk-weaving industry from east to west.”This involves introducing advanced silk production techniques from the eastern regions into Yunnan to enhance and enrich its local silk industry,thereby establishing it as a traditional national sector and securing a competitive position within the global silk market.The historical experience of Yunnan’s silk industry demonstrated that economic development opportunities can only be seized through proactive endeavors rather than passive anticipation.The modern Yunnan silk industry,which upholds its historical traditions,continues to actively engage in international high-end technical cooperation,thus ensuring the enduring vitality of the ancient“Southern Silk Road.” 展开更多
关键词 Southern Silk Road Bashu area yunnan silk-weaving technique
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Exploring Paths for the High-Quality Development of Forest-Based Wel ness Industry:A Case Study of Sichuan Province
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作者 Jin Xiaoqin Li Jing 《Contemporary Social Sciences》 2024年第3期77-91,共15页
The forest-based wellness industry,as a rapidly growing sector that integrates various business forms with extensive coverage and an extended industrial chain,is undergoing rapid development due to the increasing agin... The forest-based wellness industry,as a rapidly growing sector that integrates various business forms with extensive coverage and an extended industrial chain,is undergoing rapid development due to the increasing aging population and people's suboptimal health conditions.As a forerunner in developing the forest-based wellness industry,Sichuan province is known for its early development,proactive efforts,diverse models,and significant impact in this industry.It has achieved certain milestones in terms of top-level design,pilot demonstration,standardized guidance,and public awareness campaigns to promote the development of this industry.Therefore,this paper utilizes Sichuan as a case study to systematically summarize and analyze the key practices made by the province in promoting the rapid development of the industry by investigating the development trajectory of the forest-based wellness industry.Additionally,it examines the development trends of this industry from the perspectives of supply,demand,and consumption.Finally,this paper proposes several measures to facilitate the high-quality development of the forest-based wellness industry.These measures encompass nurturing specialized talent in forest-based wellness,enhancing market players'capabilities in this domain,conducting extensive research on technologies that promote this industry,actively seeking support from relevant policies,and promoting integrated development across diverse sectors. 展开更多
关键词 forest-based wellness industry high-quality development Sichuan province
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Major Diseases and Pests of Blueberry in Guizhou Province and Progress in Their Prevention and Control
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作者 Yanling REN Shoumei WAN +10 位作者 Tao WANG Min ZHANG Lidan MA Zhi LI Youwen TIAN Haibin FU Xingning WANG Jing PENG Lingling XIAO Dandan LU Jinyu ZHAO 《Plant Diseases and Pests》 2024年第3期1-4,7,共5页
As the blueberry industry continues to evolve,the effective control of its diseases and pests has become an essential component of local agricultural development.This paper provides a comprehensive overview of the pri... As the blueberry industry continues to evolve,the effective control of its diseases and pests has become an essential component of local agricultural development.This paper provides a comprehensive overview of the principal types of blueberry diseases and pests in Guizhou Province,along with the corresponding control measures,in order to serve as a valuable reference for blueberry growers. 展开更多
关键词 BLUEBERRIES Diseases and pests Prevention and control Guizhou province
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Origin of the Yueguang gold deposit in Xinhua, Hunan Province, South China: insights from fl uid inclusion and hydrogen–oxygen stable isotope analysis
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作者 Hongxin Fan Qiang Wang +2 位作者 Yulong Yang Yao Tang Hao Zou 《Acta Geochimica》 EI CAS CSCD 2024年第2期235-254,共20页
The Yueguang gold deposit is located in Fengjia,Xinhua County,Hunan Province,South China.It represents a recently discovered small-scale gold deposit situated in the southwestern region of the Jiangnan Orogenic Belt,w... The Yueguang gold deposit is located in Fengjia,Xinhua County,Hunan Province,South China.It represents a recently discovered small-scale gold deposit situated in the southwestern region of the Jiangnan Orogenic Belt,west of the Baimashan granitic batholith.In order to discern the characteristics of the ore-formingfluids,the underlying mineralization processes,and establish a foundation for the origin of the Yueguang gold depositfluid inclusion micro-thermometry,as well as quartz hydrogen and oxygen isotope analysis,have been carried out on samples obtained from various stages of mineralization.The hydrothermal miner-alization stages within the Yueguang gold deposit can be categorized into three stages:(i)the barren,pre-ore quartz-pyrite stage(Stage Ⅰ),the quartz-pyrite-gold stage(Stage Ⅱ),and the post-ore quartz-carbonate stage(Stage Ⅲ),with the second stage being the main mineralization stage.Thefluid inclusions identified in samples from the main min-eralization stage can predominantly be described with the NaCl–H_(2)O and CO_(2)–NaCl–H_(2)O systems.These inclusions display homogenization temperatures ranging from 158.8 to 334.9℃,and thefluid salinity ranges from 0.3%to 4.0%(wt.%NaCl equiv.).Laser Raman spectroscopy analysis of individual inclusions further reveals the presence of gas-phases such as CO_(2),CH_(4),and N_(2).Isotopic analysis indicatesδ^(18)Ofluid values ranging from 3.95 to 6.7‰ and δDH_(2)O values ranging from-71.9 to-55.7‰.These results indi-cate that the ore-formingfluid of the Yueguang gold deposit belongs to metamorphic hydrothermalfluids of middle-low temperature and low salinity.In the process of ore formation,gold is transported in the form of Au(HS)2-complexes,with gold deposition being driven byfluid immiscibility.Therefore,the Yueguang gold deposit is categorized as an orogenic gold deposit dominated by metamorphic hydrother-malfluid.It may become a new target for gold exploration in the Baimashan region,central Hunan Province. 展开更多
关键词 Hunan province Yueguang gold deposit Fluid inclusions Hydrogen–oxygen isotopes Laser Raman Fluid immiscibility Orogenic gold deposit
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Analysis on the Development Model of Relic and Museum Tourism Products Based on ERP Analysis:A Case Study on Shandong Province
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作者 WANG Xia 《Journal of Landscape Research》 2024年第1期77-82,共6页
In recent years, the trend of people choosing relic and museum tourism during their vacationand leisure time is growing day by day, mainly because it touches people's feelings about historical relicsand cultural h... In recent years, the trend of people choosing relic and museum tourism during their vacationand leisure time is growing day by day, mainly because it touches people's feelings about historical relicsand cultural heritage. The development of relic and museum tourism products is not only the inheritanceof culture and the protection of cultural relics, but also the promotion of tourism consumption under thebackground of cultural tourism integration, which has promoted the development of regional economy.With the relic and museum tourism resources in Shandong Province as the research object, through theanalysis of its resources, market and products, this paper put forward three applicable modes of relic andmuseum tourism product development, including independent development, joint development, and artauthorization, and proposed specific suggestions around the three modes. 展开更多
关键词 ERP analysis Relic and museum tourism Product development Shandong province
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Problems and Development Suggestions of Nature Education in Jiangxi Province
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作者 Hua LI Shinan XIANG Feiping CHEN 《Meteorological and Environmental Research》 2024年第1期46-47,56,共3页
The forest coverage rate of Jiangxi Province ranks second in China.It has rich natural resources,a long history of ancient color culture and rich red culture.In the development of nature education,Jiangxi Province has... The forest coverage rate of Jiangxi Province ranks second in China.It has rich natural resources,a long history of ancient color culture and rich red culture.In the development of nature education,Jiangxi Province has great potential and advantages.This paper introduces the development conditions of nature education in Jiangxi Province,summarizes the problems existing in the development of nature education in Jiangxi Province from the aspects of the types of nature education and the construction of nature education base,such as simple content and single form,imperfect infrastructure and lack of professionals,and puts forward some suggestions on the development of nature education in Jiangxi Province. 展开更多
关键词 Jiangxi province Nature education PROBLEM Development suggestion
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Plume-lithosphere interaction in the Comei Large Igneous Province: Evidence from two types of mafic dykes in Gyangze, south Tibet, China
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作者 Ya-ying Wang Ling-sen Zeng +6 位作者 Li-e Gao Li-long Yan Ling-hao Zhao Jia-hao Gao Ying-long Di Guang-xu Li Yi-hong Tian 《China Geology》 CAS CSCD 2024年第1期80-90,共11页
Two suites of mafic dykes,T1193-A and T1194-A,outcrop in Gyangze area,southeast Tibet.They are in the area of Comei LIP and have indistinguishable field occurrences with two other dykes in Gyangze,T0902 dyke with 137.... Two suites of mafic dykes,T1193-A and T1194-A,outcrop in Gyangze area,southeast Tibet.They are in the area of Comei LIP and have indistinguishable field occurrences with two other dykes in Gyangze,T0902 dyke with 137.7±1.3 Ma zircon age and T0907 dyke with 142±1.4 Ma zircon age reported by Wang YY et al.(2016),indicating coeval formation time.Taking all the four diabase dykes into consideration,two different types,OIB-type and weak enriched-type,can be summarized.The“OIB-type”samples,including T1193-A and T0907 dykes,show OIB-like geochemical features and have initial Sr-Nd isotopic values similar with most mafic products in Comei Large Igneous Provinces(LIP),suggesting that they represent melts directly generated from the Kerguelen mantle plume.The“weak enriched-type”samples,including T1194-A and T0902 dykes,have REEs and trace element patterns showing withinplate affinity but have obvious Nb-Ta-Ti negative anomalies.They show uniform lowerεNd(t)values(−6‒−2)and higher 87Sr/86Sr(t)values(0.706‒0.709)independent of their MgO variation,indicating one enriched mantle source.Considering their closely spatial and temporal relationship with the widespread Comei LIP magmatic products in Tethyan Himalaya,these“weak enriched-type”samples are consistent with mixing of melts from mantle plume and the above ancient Tethyan Himalaya subcontinental lithospheric mantle(SCLM)in different proportions.These weak enriched mafic rocks in Comei LIP form one special rock group and most likely suggest large scale hot mantle plume-continental lithosphere interaction.This process may lead to strong modification of the Tethyan Himalaya lithosphere in the Early Cretaceous. 展开更多
关键词 OIB type diabase Comei Large Igneous province Weakly enriched diabase Plume-lithosphere interaction Nb-Ta-Ti negative anomaly Kerguelen plume Geological survey engineering Tibet Plateau
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Spatio-temporal Evaluation of Multi-scale Cultivated Land System Resilience in Black Soil Region from 2000 to 2019:A Case Study of Liaoning Province,Northeast China
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作者 WANG Yue JIANG Yuting ZHU Guoxu 《Chinese Geographical Science》 SCIE CSCD 2024年第1期168-180,共13页
It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food security.The CLSR is impacted by planting structure adjustment and cult... It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food security.The CLSR is impacted by planting structure adjustment and cultivated land quality decline,posing major hidden dangers to food security.It is urgent to evaluate the CLSR at multiple spatio-temporal scales.This study took Liaoning Province in the black soil region of Northeast China as an example.Based on the resilience theory,this study constructed the CLSR evaluation system from the input-feedback perspective at the provincial-scale and the city-scale,and used the rank-sum ratio comprehensive evaluation method(RSR) to analyze the key influencing factors of CLSR in Liaoning Province and its 14 cities from 2000 to 2019.The results showed that:1) the time series changes of CLSR at the provincial-scale and the city-scale in Liaoning Province were similar,both showing an increasing trend.2) The CLSR in Liaoning Province presented a spatial pattern of ‘high in the west and low in the east’ at the city-scale.3) There were seven and six main influencing factors of CLSR at the provincial-scale and the city-scale,respectively.In addition to the net income per capita of rural households,other influencing factors of CLSR were different at the provincial-scale and the city-scale.The feedback factors were dominant at the provincial-scale,and the input factors and feedback factors were dominant at the city-scale.The results could provide a reference for the utilization of black soil and draw on the experience of regional agricultural planning and adjustment. 展开更多
关键词 cultivated land system resilience(CLSR) rank-sum ratio comprehensive evaluation(RSR) multi-scales influencing factors black soil region Liaoning province China
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Shape Analysis of Agricultural Parcels for Land Consolidation Priorities in Tekirdag Province,Turkey
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作者 Bahadir ALTURK 《Chinese Geographical Science》 SCIE CSCD 2024年第1期93-105,共13页
Shape irregularity,a sub-factor of parcel fragmentation is a problem that hinders sustainable agriculture and is solved using land consolidation projects.Determination of the parcel shape degree contributes significan... Shape irregularity,a sub-factor of parcel fragmentation is a problem that hinders sustainable agriculture and is solved using land consolidation projects.Determination of the parcel shape degree contributes significantly to spatial prioritization where there is also a high probability of achieving positive effects of consolidation projects.This study aims to determine the shape degree of the agricultural parcels both at singular and rural county scales in Tekirdag Province,Turkey in 2020 by combining the parcel shape index(PSI) with the minimum bounding geometry index(MBG) to improve parcel scores.Hot-spot zones of the highly irregular and near optimum parcels were also determined using Getis-Ord G_(i)^(*) statistic.The parcel degrees were classified into four categories,namely highly irregular,irregular,regular and near optimum.The obtained unweighted scores of the parameters exhibit deviations from the expected values.After weighting by pairwise comparison,the values approached ideal scores.Among 346 740 parcels,53% were highly irregular and irregular and 47% were regular and near optimum shapes after weighting whereas these were 70% and 30%,respectively before weighting.The average parcel degree of 63 rural counties was regular while the average parcel degree of the remaining 264 rural counties was irregular.The combined use of PSI and MBG index improved the correctness of the parcel shape score.It could be suggested to use as a tool in land consolidation prioritization. 展开更多
关键词 land consolidation priority parcel shape index(PSI) minimum bounding geometry(MBG) sustainable rural development hot-spot analysis Tekirdag province TURKEY
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Investigation and analysis of vascular plant resources and diversity in Wuyi Mountain,Fujian Province
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作者 Peiying Chen Ruru Xiong +14 位作者 Jun Yuan Minglong Huang Zhuo Tao Bowen Zhang Fanglin Luo Lisha Liu Qian Wang You Zhou Haofan Zhang Zijie Wei Jie Yang Jiangang Chen Kui Wu Anhua Wang Jingming Jia 《Asian Journal of Traditional Medicines》 2024年第1期26-33,共8页
Wuyi Mountain,located in the north of Fujian Province,China,is renowned for its abundant medicinal plant resources.In July 2014,the 8th(second team)of Shenyang Pharmaceutical University’s Chinese Medicine Resources S... Wuyi Mountain,located in the north of Fujian Province,China,is renowned for its abundant medicinal plant resources.In July 2014,the 8th(second team)of Shenyang Pharmaceutical University’s Chinese Medicine Resources Scientific Expedition Team conducted field investigation in the area.Through specimen collection and extensive literature review,the team identified and analyzed 223 vascular plant species from 175 genera and 85 families.The most dominant families were Compositae and Rosaceae,and perennial herbs were the predominant species,accounting for 44.39%of the total species identified.Notably,we documented five precious and rare medicinal plants unique to Wuyi Mountain.This study updates the database of plant resources and diversity in the region,providing a valuable reference for future studies.Finally,we put forward some suggestions to enhance the conservation and sustainable utilization of Wuyi Mountain’s plant resources. 展开更多
关键词 plant resources BIODIVERSITY MEDICINAL protection and utilization resource survey Fujian province
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The Spatial-Temporal Characteristics of Meteorological Disasters in the Southwest Region of Zhejiang Province during 1953-2022
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作者 Qi Zhang Yifan Wang +3 位作者 Zhidan Zhu Hongxia Shi Wenhao Yang Shujie Yuan 《Journal of Geoscience and Environment Protection》 2024年第3期16-27,共12页
Meteorological disasters are some of the most serious and costly natural disasters, which have larger effects on economic and social activity. Liuchun Lake is an ecotourism area in the southwest region of Zhejiang pro... Meteorological disasters are some of the most serious and costly natural disasters, which have larger effects on economic and social activity. Liuchun Lake is an ecotourism area in the southwest region of Zhejiang province, where also has experienced meteorological disasters including rainstorm and cold wave. Understanding the temporal-spatial characteristics of meteorological disasters is important for the local tourism and economic development. Based on the daily temperature and precipitation from 18 meteorological stations in the southwest of Zhejiang province during 1953-2022 and some statistical approaches, the temporal and spatial characteristics of meteorological disasters (Freezing, Rainstorm, Cold wave) are analyzed. The results indicate that 1) Rainstorm occurred frequently around the Liuchun lake, the frequency was about 8 times/a, it can also reach about 3 times/a in the other region. Freezing and cold wave (including strong cold wave and extremely cold wave) had the same spatial distribution as rainstorm, however, except for Liuchun lake, they occurred less than one time in the other regions;2) The trend of rainstorm had larger spatial difference, it increased in all the study area, but it increased more significantly around the study area than around Liuchun lake. Freezing was on the downtrend in the whole region, with 93.3% of the stations passed the 95% significant level. Cold wave also showed a declined trend, but it was insignificantly at most of the stations, only 33% of the stations passed the 90% significant level. Compared with cold wave, strong cold wave and extremely strong cold wave had weaker decline in all the regions. In general, from 1953 to 2022 rainstorm showed an increasing trend, it was the main meteorological disaster in the study area, cold wave displayed a decreasing trend, but it still occurred about 2 - 3 times/a in most regions. 展开更多
关键词 Southwest of Zhejiang province RAINSTORM Cold Wave Spatial Distribution Trend Analysis
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Winter Wheat Yield Estimation Based on Sparrow Search Algorithm Combined with Random Forest:A Case Study in Henan Province,China
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作者 SHI Xiaoliang CHEN Jiajun +2 位作者 DING Hao YANG Yuanqi ZHANG Yan 《Chinese Geographical Science》 SCIE CSCD 2024年第2期342-356,共15页
Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous r... Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous research has paid relatively little attention to the interference of environmental factors and drought on the growth of winter wheat.Therefore,there is an urgent need for more effective methods to explore the inherent relationship between these factors and crop yield,making precise yield prediction increasingly important.This study was based on four type of indicators including meteorological,crop growth status,environmental,and drought index,from October 2003 to June 2019 in Henan Province as the basic data for predicting winter wheat yield.Using the sparrow search al-gorithm combined with random forest(SSA-RF)under different input indicators,accuracy of winter wheat yield estimation was calcu-lated.The estimation accuracy of SSA-RF was compared with partial least squares regression(PLSR),extreme gradient boosting(XG-Boost),and random forest(RF)models.Finally,the determined optimal yield estimation method was used to predict winter wheat yield in three typical years.Following are the findings:1)the SSA-RF demonstrates superior performance in estimating winter wheat yield compared to other algorithms.The best yield estimation method is achieved by four types indicators’composition with SSA-RF)(R^(2)=0.805,RRMSE=9.9%.2)Crops growth status and environmental indicators play significant roles in wheat yield estimation,accounting for 46%and 22%of the yield importance among all indicators,respectively.3)Selecting indicators from October to April of the follow-ing year yielded the highest accuracy in winter wheat yield estimation,with an R^(2)of 0.826 and an RMSE of 9.0%.Yield estimates can be completed two months before the winter wheat harvest in June.4)The predicted performance will be slightly affected by severe drought.Compared with severe drought year(2011)(R^(2)=0.680)and normal year(2017)(R^(2)=0.790),the SSA-RF model has higher prediction accuracy for wet year(2018)(R^(2)=0.820).This study could provide an innovative approach for remote sensing estimation of winter wheat yield.yield. 展开更多
关键词 winter wheat yield estimation sparrow search algorithm combined with random forest(SSA-RF) machine learning multi-source indicator optimal lead time Henan province China
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Research on the Internal Talent Training Path and Performance Evaluation Mechanism of New R&D Institutions in Zhejiang Province
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作者 Xiangjiang Li 《Proceedings of Business and Economic Studies》 2024年第2期100-105,共6页
New research and development(R&D)institutions are an important part of the national innovation system,playing an important role in promoting the transformation of scientific and technological achievements.In recen... New research and development(R&D)institutions are an important part of the national innovation system,playing an important role in promoting the transformation of scientific and technological achievements.In recent years,new R&D institutions have gradually become the driving force of innovation-driven development in China.Taking new R&D institutions in Zhejiang Province as the research object,this paper studies the internal talent training path and performance evaluation mechanism of new R&D institutions in Zhejiang Province by using the literature research method,comparison method,case verification method,and other methods.The investigation results show that there are problems such as lack of material and spiritual support and neglect of the absorption of local talents in the internal talent training,and there are problems such as unclear standards,insufficient data,and opaque processes in the performance evaluation mechanism,which greatly affect the establishment and improvement of the performance evaluation mechanism.Given the above problems,this paper puts forward a forward-looking,oriented,flexible,and compatible talent training path and performance evaluation mechanism,hoping to optimize the effective internal talent training path of new R&D institutions,improve the evaluation performance,and promote healthy development of new R&D institutions in Zhejiang Province. 展开更多
关键词 INNOVATION New R&D institutions Zhejiang province Talent cultivation Performance evaluation mechanism
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Analysis of the Current Situation of Drug Clinical Trial Institutions in Shaanxi Province
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作者 Yurong Zhang Qi Zhang +4 位作者 Li Wang Rui Xu Lili Zhao Enze Li Xin Wang 《Journal of Clinical and Nursing Research》 2024年第1期78-87,共10页
To understand the current situation of institutional registration in Shaanxi Province after the implementation ofregistration system management in drug clinical trial institutions.Relevant information was collected on... To understand the current situation of institutional registration in Shaanxi Province after the implementation ofregistration system management in drug clinical trial institutions.Relevant information was collected on the“Announcement on the Accreditation of Drug Clinical Trial Institutions”issued by the National Medical Products Administration from 2005 to August 2022,the record management information system of drug and medical device clinical trial institutions,and the drug clinical trial registration and information publicity platform.A retrospective analysis was carried out in terms of institutional development,regional distribution,registered majors,principal investigators,and the number of drug clinical trials.After the implementation of institution registration,the number of drug clinical trial institutions in Shaanxi Province increased by 47.4%,884 principal investigators were registered,the number of registered majors expanded from 58 qualified to 117,and the professional scope increased by 50.4%.The policy of institution registration is conducive to promoting the rational use of medical resources and the development of drug clinical trial institutions and improving the healthy development of the pharmaceutical industry in Shaanxi Province. 展开更多
关键词 Drug clinical trial Institution registration Registered majors Current situation analysis Professional group Shaanxi province
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The coda attenuation of the Yao'an area in Yunnan Province 被引量:59
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作者 李白基 秦嘉政 +1 位作者 钱晓东 叶建庆 《地震学报》 CSCD 北大核心 2004年第1期47-52,共6页
2000年1月15日云南姚安发生了6.5级地震.震后围绕震中区架设了一个由6套拾震器-记录仪组成的临时数字地震台网.在所记录的余震中,有402次余震有较精确的定位.依照Sato的单散射模型分析观测的尾波短记录,获得了姚安地区地壳的尾波... 2000年1月15日云南姚安发生了6.5级地震.震后围绕震中区架设了一个由6套拾震器-记录仪组成的临时数字地震台网.在所记录的余震中,有402次余震有较精确的定位.依照Sato的单散射模型分析观测的尾波短记录,获得了姚安地区地壳的尾波平均品质因子Qc(f)=49f^0.95,f=1.5~20.0Hz,具有高构造活动性区域的衰减特征. 展开更多
关键词 Sato单散射模型 尾波衰减 地震定位 地震波 数字地震台网
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