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Research on Identification Method of Apple Diseases in Southern Xinjiang Based on Deep Learning and Its System Implementation
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作者 Peng QIN Nannan ZHANG +1 位作者 Rong WU Lijun GAO 《Agricultural Biotechnology》 CAS 2023年第5期78-82,共5页
Apple disease samples were collected from the southern Xinjiang and annotated to design a convolutional neural network model based on deep learning.The accuracy and robustness of the model was improved through trainin... Apple disease samples were collected from the southern Xinjiang and annotated to design a convolutional neural network model based on deep learning.The accuracy and robustness of the model was improved through training and optimization algorithms,and a complete apple disease identification system was developed with the model as the core,and evaluated for its performance in terms of accuracy,recall rate and speed.This study provides a reliable AI-based apple disease diagnosis solution for the apple planting industry in the southern Xinjiang,hoping to help farmers better manage and protect crop health. 展开更多
关键词 Deep learning Convolutional neural network Apple disease identification southern xinjiang System implementation
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Exploration on Ideological and Political Construction of Higher Vocational English Course in Southern Xinjiang from the Perspective of "Cultural Confidence"
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作者 Huiqin LIU Maierhaba·Ababake +1 位作者 Lilian YANG Lidan HE 《Asian Agricultural Research》 2023年第3期66-69,共4页
At present,the lack of Chinese culture in higher vocational English teaching in southern Xinjiang is serious.The existing English curriculum system is not enough to support the goal of cultivating ethnic minority coll... At present,the lack of Chinese culture in higher vocational English teaching in southern Xinjiang is serious.The existing English curriculum system is not enough to support the goal of cultivating ethnic minority college students cultural confidence,and its curriculum ideological and political construction is still in the initial stage of exploration.The combination of the Chinese national culture and the ethnic culture of Xinjiang and the ideological and political elements organically integrated into cultural confidence have endowed the vocational English education in Xinjiang with the characteristics of the times.In this paper,from the perspective of China s"cultural confidence",ideological and political elements were explored,and the background of ideological and political construction in higher vocational English teaching course in southern Xinjiang was analyzed;it is expounded that the ideological and political construction is an inevitable requirement for the high-quality development of vocational English education in southern Xinjiang,and the content design and implementation path of higher vocational English course was explored to provide new ideas and new ways for the curriculum ideological and political construction of higher vocational English teaching in southern Xinjiang. 展开更多
关键词 Cultural confidence southern xinjiang Vocational English Ideological and political construction
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Effects of irrigation on precipitation in the arid regions of Xinjiang,China 被引量:4
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作者 Yong ZHAO YongJie FANG +1 位作者 CaiXia CUI AnNing HUANG 《Journal of Arid Land》 SCIE 2012年第2期132-139,共8页
Soil moisture is an important parameter for the interaction between soil and atmosphere. It is the sec- ond important factor that influences climate change, next to sea surface temperature (SST). Most previous studi... Soil moisture is an important parameter for the interaction between soil and atmosphere. It is the sec- ond important factor that influences climate change, next to sea surface temperature (SST). Most previous studies focused on the monsoon regions in East China, and only a few laid emphases on arid environments. In Xinjiang, which is located in Northwest China, the climate is typically arid and semi-arid. During the past 20 years, the pre- cipitation in Xinjiang has shown a significant increasing trend, and it is closely related to oasis irrigation. This paper aims at discussing whether abnormal soil moisture in spring can be the signal to forecast summer precipitation. The effects of abnormal soil moisture due to farm irrigation in spring in arid environments on regional climate are inves- tigated by using a regional climate model (RegCM3). The results indicate that positive soil moisture anomaly in irrigated cropland surface in May led to an increase in precipitation in spring as well as across the whole summer. The impact could last for about four months. The effects of soil moisture on the surface air temperature showed a time-lagging trend. The summer air temperature declined by a maximum amplitude of 0.8℃. The increased soil moisture could enhance evaporation and ascending motion in the low troposphere, which brought in more precipi- tation. The soil moisture affected regional weather and climate mainly by altering the surface sensible and latent heat fluxes. 展开更多
关键词 IRRIGATION abnormal soil moisture weather and climate effects PRECIPITATION arid region xinjiang
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Current Status of Greenhouse Tomato Production in Aksu Area of Southern Xinjiang 被引量:1
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作者 Chunling WANG Weitang SONG 《Agricultural Biotechnology》 CAS 2019年第2期59-62,共4页
With the implementation of the "13^(th) Five-Year Plan" to promote the border area and raise rural living standards, the Xinjiang Production and Construction Corps has paid more and more attention to the dev... With the implementation of the "13^(th) Five-Year Plan" to promote the border area and raise rural living standards, the Xinjiang Production and Construction Corps has paid more and more attention to the development of protected agriculture, which is needed for the comprehensive development and stability of the border groups. In this paper, the current status of greenhouse tomato production in Aksu of southern Xinjiang is analyzed and summarized, finding the following: the structure is not reasonable with poor performance; the soilless cultivation mode is gradually developed, and there are innovative forms; the fertilization structure is not reasonable and needs improvement; the technical level is low, and it needs to be upgraded. Therefore, to solve the various problems that exist at present, some efforts are needed achieve a better production model. 展开更多
关键词 GREENHOUSE TOMATO PRODUCTION southern xinjiang DEVELOPMENT
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Adjusted Nutrition Solution Formula Improves the Growth and Yield of Soilless Tomato Culture in Southern Xinjiang 被引量:1
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作者 Chunling WANG Deshuai WANG 《Agricultural Biotechnology》 CAS 2022年第6期158-162,166,共6页
The tomato production facilities in southern Xinjiang have unique climatic conditions.However,due to the high salinity and degree of mineralization of the soil and the extensive management of irrigation water sources,... The tomato production facilities in southern Xinjiang have unique climatic conditions.However,due to the high salinity and degree of mineralization of the soil and the extensive management of irrigation water sources,the tomato production efficiency is low,and there is still much room for improvement.In this study,the formulas of tomato nutrient solutions were adjusted according to the local irrigation water quality characteristics,and tomato was grown in a greenhouse using sand cultivation.To select a nutrient solution formula suitable for the tomato cultivated in the local facilities,various parameters of tomato treated with different formulas were compared.The results showed the following:①Adjusting the nutrient solution formula could effectively improve the vegetative and reproductive growth indexes of tomato.②Properly decreasing the nutrient solution concentration could improve the growth indexes of tomato.③Decreases in Ca^(2+) and Mg^(2+) in the nutrient solution did not affect the growth and yield of tomato.The possible reason for the third result was that excessive cations in the water inhibited the absorption of Ca^(2+) and Mg^(2+) in the nutrient solution and had antagonistic effects.Therefore,a high nutrient solution concentration does not necessarily promote the growth of tomatoes.In summary,this study will improve the production conditions of protected tomato in the southern Xinjiang area by supporting tomato nutrient solution adjustments according to actual conditions in combination with reasonable irrigation systems and scientific management. 展开更多
关键词 Nutrition Solution Tomato Growth Yield southern xinjiang
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Comparative Research on the Economic Development of Xinjiang i n the Perspective of Development of the West Regions
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作者 Xuehelaiti.Mahemuti 《Asian Agricultural Research》 2011年第6期35-42,共8页
In the context of Development of the West Regions, by using the annual data from 1999 to 2009 in whole China and 12 provinces of the western regions, we analyze the achievements of socio-economic development of Xinjia... In the context of Development of the West Regions, by using the annual data from 1999 to 2009 in whole China and 12 provinces of the western regions, we analyze the achievements of socio-economic development of Xinjiang Uygur Autonomous Region from 1999 to 2009 as follows: the economic aggregate has increased prominently and the growth rate is increasing ceaselessly; the primary industry, secondary industry and tertiary industry develop evenly, and the industrial structure is incessantly optimized; the quality of economic growth is promoted increasingly and the living standard of people is improved greatly; the primary industry, secondary industry and tertiary industry stride in tandem, and the momentum of growth is strong. We conduct horizontal comparison on the main economic indicators of Xinjiang, 12 provinces of the western regions and whole China, which include GDP and its growth rate, investment of fixed assets, structure of the primary industry, secondary industry and tertiary industry, the industrial added value, GDP per capita, gross retail sales of social consumption, export and import trade, net income per capita of peasants and herdsmen, and general budget revenue. The result shows that although the implementation of the strategy of Development of the West Regions and the economic development of Xinjiang have achieved some remarkable results, there is a conspicuous gap in comparison with the expected effect. The problems existing in the operation of Xinjiang's economy are analyzed as follows: the industrial level is low, and the economic growth mode is yet to be transformed; the disposable income per capita of urban residents grows slowly, and the increasing gap between the urban areas and rural areas has no trend of dwindling; the investment aggregate is very low, and the momentum of economic growth is short. In order to make the central government and 19 provinces and cities offer pointed aid for Xinjiang, promote the implementation of new strategic development of Western China, and promote the better economic development of Xinjiang in the period of the Twelfth Five-Year Plan, we put forward some feasible suggestions as follows: Xinjiang should grasp favorable opportunities and quicken the pace of industrial structural adjustment; continue to open up to the outside world unswervingly, and improve investment environment ceaselessly; strive to maintain the continuous and rapid development of economy, and improve the living standard of people. 展开更多
关键词 DEVELOPMENT of the WEST regions xinjiang ECONOMIC
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Helicobacter pylori infection in Xinjiang Uyghur Autonomous Region:Prevalence and analysis of related factors 被引量:1
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作者 Yu-Hua Peng Xue Feng +2 位作者 Zhong Zhou Lei Yang Yun-Fei Shi 《World Journal of Gastroenterology》 SCIE CAS 2023年第43期5834-5847,共14页
BACKGROUND^(14)C urea breath test(^(14)C UBT)and immunohistochemical staining(IHC)are widely used for detection Helicobacter pylori(H.pylori)infection with different sensitivity,and there is a difference in H.pylori i... BACKGROUND^(14)C urea breath test(^(14)C UBT)and immunohistochemical staining(IHC)are widely used for detection Helicobacter pylori(H.pylori)infection with different sensitivity,and there is a difference in H.pylori infection rate in Uyghur and Han ethnic groups.Both need large cohort studies to evaluate the differences more accurately.AIM To analyze the difference between^(14)C UBT and IHC for H.pylori detection in Xinjiang Uyghur Autonomous Region and the difference between Uyghur and Han populations.METHODS There were 3944 cases of H.pylori infection detected by both IHC and^(14)C UBT at the same time(interval<1 wk,with sampling site including gastric antrum,selected from 5747 patients).We compared the sensitivity of^(14)C UBT and IHC.We also compared 555 pairs of Han/Uyghur cases(completely matched for gender and age)for their H.pylori infection rates.The overall H.pylori infection rate of all 5747 cases and the correlation with other clinicopathological data were also further analyzed.SPSS V23.0 software was used for statistical analysis.RESULTS The sensitivity was 94.9%for^(14)C UBT and 65.1%for IHC,which was a significant difference(n=3944,P<0.001).However,among those cases negative for H.pylori by^(14)C UBT(detection value≤100),4.8%were positive by IHC.Combining both methods,the overall H.pylori infection rate was 48.6%(n=5747),and differences in gender,age group,ethnicity and region of residence significantly affected the H.pylori positive rates.According to age group(Han/Uyghur),the positive rates were≤30 years(62.2%/100.0%),31-40 years(45.2%/85.7%),41-50 years(47.2%/79.2%),51-60 years(44.6%/76.1%),61-70 years(40.9%/68.2%),71-80 years(41.7%/54.1%)and≥81 years(42.9%/NA).The H.pylori infection rates of Han/Uyghur paired cases were 41.4%and 73.3%,which was a significant difference(P<0.001)(555 pairs).H.pylori positivity was significantly related to moderate-severe grade 2-3 chronic/active gastritis and intestinal metaplasia(all P<0.05).CONCLUSION The sensitivity of^(14)C UBT was significantly higher,but combined application can still increase the accuracy.The prevention H.pylori should be emphasized for Uygur and young people. 展开更多
关键词 Helicobacter pylori IMMUNOHISTOCHEMISTRY 14C urea breath test HAN UYGHUR xinjiang Uyghur Autonomous Region
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SHRIMP U-Pb Zircon Age of the Ka'erjiao Intrusion in the Sawur Region in West Junggar,Xinjiang 被引量:9
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作者 ZHOU Taofa TAN Lugui +4 位作者 FAN Yu YUAN Feng YANG Wenping HE Lixin YUE Shucang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第2期322-329,共8页
Acid intrusions are widespread in the Sawur region, Xinjiang. The Ka'erjiao intrusion is mainly composed of albite granite porphyry, K-feldspar granite porphyry, ivernlte and granite porphyry. Being a transitional pr... Acid intrusions are widespread in the Sawur region, Xinjiang. The Ka'erjiao intrusion is mainly composed of albite granite porphyry, K-feldspar granite porphyry, ivernlte and granite porphyry. Being a transitional product between magma intrusion and eruption in the Sawur region, the Ka'erjiao intrusion was formed at the telophase of the late Carboniferous to the begining of early Permian as determined by the SHRIMP U-Pb zircon dating, with an age of 302.6±7.6 Ma (1 σ). The intrusion consists of alkali-enriched rock, whose REE distribution patterns are of the LREE enrichment type, the δEu value is low and Nd, St, Pb isotopes reflect its mantle source characteristics. The δ^18O value of intrusion is low as a result of isotope exchange with meteoric water. The geochemical characteristics show that it was formed in a post-collisional tectonic setting. Taking combined considerations of current studies of A-type granites and Permian volcanic rocks, we think that in the telophase of the late Carboniferous to the beginning of the early Permian, the Sawur region was within the extension or compressional to extensional period of a post-collisionai stage. The Ka'erjiao intrusion from mantle sources can confirm the vertical continental crust growth in the late Paleozoic. The Sawur region in west Junggar is consistent with east Junggar in post-collisionai tectonic evolution process. 展开更多
关键词 granite ZIRCON SHRIMP data POST-COLLISION Sawur region xinjiang
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Re-Os Isotopic Dating of a W-Be Polymetallic Deposit in the Southern Qinling Region, China 被引量:5
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作者 DAI Hongzhang WANG Denghong +1 位作者 WANG Chenghui HUANG Fan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第1期414-415,共2页
Objective In recent years, a series of tungsten prospecting breakthroughs have been made in the southern Qinling Mountains. Especially, a new deposit type with a scheelite -beryl-molybdenite assemblage in the Zhen'a... Objective In recent years, a series of tungsten prospecting breakthroughs have been made in the southern Qinling Mountains. Especially, a new deposit type with a scheelite -beryl-molybdenite assemblage in the Zhen'an area of Shaanxi Province was firstly discovered. This deposit is currently in a detailed investigation stage, and no detailed study has been yet conducted. This work selected one molybdenite sample from the Be (W) ores in this deposit for Re-Os isotope measurements to define the time limit of tungsten and beryllium mineralization, and to further reveal the ore-forming geological setting of rare metals in the southern Qinling region. 展开更多
关键词 Re-Os Isotopic Dating Re-Os Isotopic Dating of a W-Be Polymetallic Deposit the southern Qinling Region
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Response of Artificial Grassland Carbon Stock to Management in Mountain Region of Southern Ningxia, China 被引量:7
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作者 TANG Long DANG Xiaohu +2 位作者 LIU Guobin SHAO Chuanke XUE Sha 《Chinese Geographical Science》 SCIE CSCD 2014年第4期436-443,共8页
Grassland is a major carbon sink in the terrestrial ecosystem. The dynamics of grassland carbon stock profoundly influence the global carbon cycle. In the published literatures so far, however, there are limited studi... Grassland is a major carbon sink in the terrestrial ecosystem. The dynamics of grassland carbon stock profoundly influence the global carbon cycle. In the published literatures so far, however, there are limited studies on the long-term dynamics and influential factors of grassland carbon stock, including soil organic carbon. In this study, spatial-temporal substitution method was applied to explore the characteristics of Medicago sativa L. (alfalfa) grassland biomass carbon and soil organic carbon density (SOCD) in a loess hilly region with different growing years and management patterns. The results demonstrated that alfalfa was the mono-dominant community during the cutting period (viz. 0-10 year). Community succession began after the abandonment of alfalfa grassland and then the important value of alfalfa in the community declined. The artificial alfalfa community abandoned for 30 years was replaced by the S. bungeana community. Accordingly, the biomass carbon density of the clipped alfalfa showed a significant increase over the time during 0-10 year. During 0-30 year, the SOCD from 0-100 cm of the soil layer of all 5 management patterns increased over time with a range between 5.300 ± 0.981 kg/m2 and 12.578 ± 0.863 kg/m2. The sloping croplands had the lowest SOCD at 5.300 ± 0.981 kg/m2 which was quite different from the abandoned grasslands growing for 30 years which exhibited the highest SOCD with 12.578 ± 0.863 kg/m2. The ecosystem carbon density of the grassland clipped for 2 years increased 0.1 kg/m2 compared with the sloping cropland, while that of the grassland clipped for 10 years substantially increased to 10.30 ± 1.26 kg/m2. Moreover, the ecosystem carbon density for abandoned grassland became 12.62± 0.50 kg/m2 at 30 years. The carbon density of the grassland undisturbed for l0 years was similar to that of the sloping cropland and the grassland clipped for 2 years. Different management patterns imposed great different effects on the accumulation of biomass carbon on artificial grasslands, whereas the ecosystem carbon density of the grassland showed a slight increase from the clipping to abandonment of grassland in general. 展开更多
关键词 artificial Medicago sativa L. (alfalfa) grassland clipped grassland abandoned grassland carbon sink carbon density mountain region southern Ningxia
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Ambient tectonic shear stress field in Southern California and seismic hazard regions 被引量:1
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作者 陈培善 肖磊 +1 位作者 白彤霞 成瑾 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第2期20-29,共10页
ccording to the fracture mechanics rupture model of earthquakes put forward by us, several equations to compute tectonic ambient shear stress value τ0 have been derived [equations (1), (2), (3), (5)].τ0 values for i... ccording to the fracture mechanics rupture model of earthquakes put forward by us, several equations to compute tectonic ambient shear stress value τ0 have been derived [equations (1), (2), (3), (5)].τ0 values for intermediate and small earthquakes occurred in Chinese mainland and Southern California have been calculated by use of these equations. The results demonstrate that the level and distribution of τ0 are closely related to the location where large earthquakes will occur, i.e. the region with higher level of τ0 will be prone to occur large earthquakes and the region with lower level will usually occur small earthquakes. According to the spatial distribution of τ0 , the seismic hazard regions or the potential earthquake source regions can in some degree be determined. According to the variation of τ0 with time, the large earthquake occurrence time can be roughly estimated. According to the distribution of τ0 in Southern California and variation with time, three high stress level regions are determined, one (Goldfield area) of them is the present seismic hazard region. 展开更多
关键词 tectonic ambient shear stress field southern California seismic hazard region potential earthquake source region
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Dynamic Simulation of Land Use in the Southern Loess Plateau 被引量:1
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作者 Bin GUO 《Asian Agricultural Research》 2014年第5期52-54,59,共4页
To study the dynamic changes of land use and predict the future land use scenarios based on the current land use,this paper uses Cellular Automata- Markov( CA- Markov) model to simulate the landscape pattern in 2030. ... To study the dynamic changes of land use and predict the future land use scenarios based on the current land use,this paper uses Cellular Automata- Markov( CA- Markov) model to simulate the landscape pattern in 2030. The results show that in the study area during the period 1980- 2005,grassland and construction land increased,and woodland increased slightly; waters and unused land decreased,and arable land underwent dramatic changes. The simulation precision of CA- Markov model is 87. 28%,indicating that the use of it for simulation is reliable. The land use of the study area will be changed greatly in the future. This method provides a reference for the regions to carry out land prediction,and the research results can provide a basis for the study of optimization of land. 展开更多
关键词 LANDSCAPE PATTERN CA-Markov RS GIS southern REGION
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Climate-Driven Changes in Lake Areas for the Last Half Century in the Valley of Lakes, Govi Region, Southern Mongolia 被引量:1
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作者 Alexander Orkhonselenge Goro Komatsu Munkhjargal Uuganzaya 《Natural Science》 2018年第7期263-277,共15页
This study presents the changes in lake areas in the Valley of Lakes, the Govi region, southern Mongolia. The recent changes in lake areas show decreases depending on vulnerability of lake basins and response of Govi ... This study presents the changes in lake areas in the Valley of Lakes, the Govi region, southern Mongolia. The recent changes in lake areas show decreases depending on vulnerability of lake basins and response of Govi landscape to the present climatic warming. During the recent 44 - 45 years (from 1970 to 2014 or 2015), modern lakes have encountered the present rapid increase in temperature, water evaporation and drying up that induced the reduction in lake areas in the Valley of Lakes. The finding of the reduction in lake areas is consistent with the trends on increasing in temperature since 1995 and fluctuating precipitation since 1975. Investigations with detailed chronology of lake sediment are needed from the lakes to review a more complete evolution of lake basins during the Late Quaternary paleoclimatic history in Mongolia and Central Asia. 展开更多
关键词 LAKES Lake Areas CLIMATE Change Govi REGION southern Mongolia
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Planting Performance of Pennisetum purpureum Schumab cv.Purple in the Southern Region of China 被引量:1
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作者 易显凤 赖志强 +4 位作者 姚娜 蔡小艳 韦锦益 赖大伟 梁永良 《Agricultural Science & Technology》 CAS 2016年第3期667-671,共5页
[Objective] The present experiment was conducted to investigate the yield,adaptability and quality characteristics of Pennisetum purpureum Schumach cv. Purple to provide reference for the certification and development... [Objective] The present experiment was conducted to investigate the yield,adaptability and quality characteristics of Pennisetum purpureum Schumach cv. Purple to provide reference for the certification and development of new varieties.[Method] With P. purpureum Schumab cv. Purple as experimental material, the variety comparison tests were conducted in Nanning, Lingyun, and Tiandeng in Guangxi from 2007 to 2009, and variety regional trials were conducted in Danzhou of Hainan, Fuzhou of Fujian and Zhanjiang of Guangdong from 2011 to 2013. Its comprehensive characters of plant height, hay yield, stem-leaf ratio and nutritional components were determined, and were compared with those of P. purpureum × P.americanum cv. Reyan No.4 and P. purpureum Schum cv. Guiminyin. [Result] The average height of P. purpureum Schumach cv. Purple was 706.54 cm, which was5.92% and 8.44% lower than that of P. purpureum × P. americanum cv. Reyan No.4 and P. purpureum Schum cv. Guiminyin, respectively. The average hay yield of P. purpureum Schumach cv. Purple was 32.74 t/ha in Nanning, Lingyun, and Tiandeng of Guangxi from 2007 to 2009, and 22.41 t/ha in Danzhou of Hainan, Fuzhou of Fujian and Zhanjiang of Guangdong from 2011 to 2013. Although its hay yield was lower than two control varieties, the difference was not significant(P 0.05).The stem-leaf ratio of P. purpureum Schumach cv. Purple was 0.98:1. Moreover,the analysis on the nutritional components of dry matter showed that compared with P. purpureum × P. americanum cv. Reyan No.4 and P. purpureum Schum cv.Guiminvin, the crude fiber of P. purpureum Schumab cv. Purple was decreased by4.76% and 2.78%, respectively; the neutral detergent fiber decreased by 5.07% and2.22%, respectively; the acid detergent fiber was decreased by 2.54% and 1.99%,respectively; the crude fat was increased by 64.29% and 43.75%, respectively; the calcium content was increased by 28.00% and 33.33%, respectively; the phosphorus content was increased by 9.68% and 22.73%, respectively; the total content of amino acid was increased by 43.23% and 68.41%, respectively; the anthocyanin content of leaf was increased by 400.00% and 216.90%, respectively(P 0.05).[Conclusion] P. purpureum Schumach cv. Purple is a new high-quality forage variety with wide adaptability, high yield, rich nutrient and good palatability, which is appropriate for comprehensive exploitation and application in the southern region of China. 展开更多
关键词 P.purpureum Schumab cv.Purple Plant height Hay yield Stem-leaf ratio Nutritional component southern region of China
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Geochemistry of the Baishitouquan Amazonite-and Topaz-bearing Granite in the Mid-Tianshan Belt, Xinjiang, China 被引量:2
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作者 顾连兴 杨浩 +2 位作者 苟晓琴 郭继春 王金珠 《Chinese Journal Of Geochemistry》 EI CAS 1994年第4期289-304,共16页
The Baishitouopan amaznito and topazbearing granite is one of the typical high-rubidium andhigh-fluorine granites in the eastern paft of the Mid-Tianshan belt. This intrusion is in sharp contactwith Mid-Proterozoic sc... The Baishitouopan amaznito and topazbearing granite is one of the typical high-rubidium andhigh-fluorine granites in the eastern paft of the Mid-Tianshan belt. This intrusion is in sharp contactwith Mid-Proterozoic schists, gneisses and marbles, and is compond of four zones transihonal fromthe bottom upwards: leucogranite, amazonite granite, topaz-bearing amazonite granite and topazquartz albitite.The Baishitouquan granite contains highly ordered K-feldspar, Li-rich mica, Mn-rich gamet,a-quartz and low-temerature rircon and is chemically high in Si, K, Na, Al, Li, Rb, Cs and F,and low in Ti, Fe, Ch, Mg, P, Ch, Ni, Cr, V, Sr and Ba, with Na2O>K2O. Amazonite fromthe amazonite granite zone contains 1867 ppm Rb. The F contents of bulk rocks are 3040 and4597 for the amazonite granite and topazbearing amazonite granite zones, respectivel. These twozones have δ18O values of 8.97 - 9.85%, (SMOW) and show flat REE distribution patterns withstrong Eu depletion. KAr and Rb-Sr ages of this intrusion are 226. 6 Ma and 209. 6 Marespectively, with an initial 87Sr/86Sr ratio of 0.987±0.213.The Baishitouquan granite is the product of crystallization of a lowtemperature, and wther,rubidium. and fluorine-rich magma , which may have been derived from partial melting ofmuscoviterich crustal rocks. Consolidation of this granite involved two contrasting and successivestagst melt crystallization and hydrothermal metasomasm and pforitation. Various geological features of this granite were formed during the transition from the magmatic to the hydrothermal stage. 展开更多
关键词 绿长石 黄玉 花岗岩 新疆 天山地区 地球化学 氧同位素 锶同位素
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Gravity and magnetic field characteristics and regional ore prospecting of the Yili ancient continent, West Tianshan, Xinjiang Uygur Autonomous Region, China 被引量:2
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作者 Xue-zhong Yu Yi-yuan He +3 位作者 Meng Wang Jian Zhang Xuan-jie Zhang Zheng-guo Fan 《China Geology》 2020年第1期104-112,共9页
Gold,iron,copper,lead-zinc and other mineral exploration in West Tianshan,Xinjiang Uygur Autonomous Region,has made remarkable progress in recent years.However,due to the dispute on the tectonic division of West Tians... Gold,iron,copper,lead-zinc and other mineral exploration in West Tianshan,Xinjiang Uygur Autonomous Region,has made remarkable progress in recent years.However,due to the dispute on the tectonic division of West Tianshan,the ore-controlling factors and the regional metallogenic laws are controversial.The authors analyze regional gravity data and notice that the high-value region corresponds to the Yili ancient continent,thus the southeastern boundary of the Yili ancient continent is delineated.Comparative analysis of gravity,aeromagnetic and geologic data reveals that the Tulasu basin,where some medium to large epithermal gold deposits locate,lies above the Yili ancient continent;the Yili Carboniferous-Permian rift extends in E-W direction,numbers of copper deposits have been found in the mid-west section of the rift which lies above the Yili ancient continent,whereas few copper deposits have been discovered in the east section which is outside the Yili ancient continent.Accordingly,the Yili ancient continent may be rich in gold,copper and other metal elements;the metal-bearing hydrothermal solution moves up with the activity of magmatism,and deposits in the favorable places(the Tulasu basin and the Yili Carboniferous-Permian rift),forming numerous small and medium gold,copper deposits,as well as some large and super-large gold deposits.Therefore,the tectonic-magmatic hydrothermal zone above the Yili ancient continent should be the prospective area for epithermal gold and copper polymetallic deposits. 展开更多
关键词 Yili ancient continent Yili Carboniferous-Permian rift Gravity field Epithermal gold deposit Copper polymetallic deposit Geophysical and remote sensing survey engineering xinjiang Uygur Autonomous Region China
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Zircon U-Pb Dating of Yushugou Terrain of High-Pressure Granulite Facies in Southern Tianshan Mountain and Its Geological Significance 被引量:1
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作者 王润三 王焰 +2 位作者 李惠民 周鼎武 王居里 《Chinese Journal Of Geochemistry》 EI CAS 2000年第1期23-28,共6页
The Yushugou terrain of high\|pressure granulite facies in southern Tianshan Mountain is composed mainly of an ophiolite suite. Most selected zircons are round or elliptical in shape, and some are of tetragonal prism ... The Yushugou terrain of high\|pressure granulite facies in southern Tianshan Mountain is composed mainly of an ophiolite suite. Most selected zircons are round or elliptical in shape, and some are of tetragonal prism with round edges. The granulometric analyses show that they are well sorted in sedimentation. ZrO\-2/HfO\-2 ratios in zircons range from 45 to 57. These characters, together with the petrologic and geochemical characters of plagioclase\|garnet\|orthopyroxenite bearing zircons, indicate that the protolith of plagioclase\|garnet\|orthopyroxenite may be derived mainly from volcanic base surge sedimentary debris in oceanic islands and from clays formed by seafloor weathering. Zircons are simply of pyroclastic debris. The ophiolite formation age of (440±18) Ma and the first\|stage metamorphic age (amphibolite or granulite facies) of (364±5) Ma were obtained with a method of multiple grains in different groups and a method of concordia plot. These ages provide important information on the temporal and spatial occurrence of southern Paleozoic Tianshan Ocean, the subduction rate of the oceanic crust and the formation mechanism of ophiolite of granulite facies. 展开更多
关键词 锆石 铀铅同位素年龄 麻粒岩 天山地区 新疆 地形 蛇绿岩 地质标志
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Xinjiang Opens Its Door to the World——An interview with Wang Lequan,Vice-Chairman of the Standing Committee of the Xinjiang Uygur Autonomous Region 被引量:1
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作者 Jiang Min 《China's Foreign Trade》 1995年第1期11-11,共1页
Xinjiang is a good place, with pastureland to the north and south of the Tianshan MountainThe Gobi Desert has been changed into fertile fields, irrigated by melting snows.
关键词 An interview with Wang Lequan Vice-Chairman of the Standing Committee of the xinjiang Uygur Autonomous Region WANG xinjiang Opens Its Door to the World
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A New Species of Ginkgo with Male Cones and Pollen Grains in situ from the Middle Jurassic of Eastern Xinjiang,China
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作者 WANG Zixi SUN Fankai +5 位作者 JIN Peihong CHEN Yingquan CHEN Jingwei DENG Peng YANG Guolin SUN Bainian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第1期9-21,共13页
Well-preserved Ginkgo pollen organs are analyzed from the Middle Jurassic Xishanyao Formation of the Turpan–Hami Basin, Xinjiang Uygur Autonomous Region, northwestern China, and are described as a new species, Ginkgo... Well-preserved Ginkgo pollen organs are analyzed from the Middle Jurassic Xishanyao Formation of the Turpan–Hami Basin, Xinjiang Uygur Autonomous Region, northwestern China, and are described as a new species, Ginkgo hamiensis Z.X. Wang et B.N. Sun sp. nov. The immature male cones are cylindrical and catkin-like, with two longitudinal stripes on the stalk. The pollen sacs are shaped like a long oval with two pollen sacs fused together for each microsporophyll, and the microsporophyll tip is a triangular cystidium. The pollen grains are oblong or fusiform and monocolpate; both ends are blunt or sharp. By comparison with previously reported fossil records of Ginkgo plants, we determined that the current fossils are different from all other reported species; thus, the present fossil is referred to as a new species of Ginkgo. The reproductive organs of the Ginkgo fossils described herein can provide valuable information for the study of Ginkgo plants. Further, there are two probable evolutionary trends in the Ginkgo pollen cones. One trend is that the number of pollen sacs changed from three or four during the Jurassic and Cretaceous to two at the present day; the other is that the number of pollen sacs has remained two from the Middle Jurassic to the present day. In addition, the pollen cones described herein are similar to the pollen cones of the extant Ginkgo, which strongly indicates that the morphology of Ginkgo plants may have remained highly conserved over millions of years. 展开更多
关键词 Ginkgo hamiensis Pollen cones Middle Jurassic xinjiang Uygur Autonomous Region Systematic evolution
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Distribution of Lg coda Q in Xinjiang and its adjacent regions
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作者 徐彦 毛燕 +2 位作者 胡家富 苏有锦 丛连理 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2005年第2期162-170,254,共10页
In this study, we collected 1156 broadband vertical components records at 22 digital seismic stations in Xinjiang region, Urumqi station, and 7 stations in the adjacent regions during the period of 1999-2003. The reco... In this study, we collected 1156 broadband vertical components records at 22 digital seismic stations in Xinjiang region, Urumqi station, and 7 stations in the adjacent regions during the period of 1999-2003. The records were firstly processed by the stacked spectral ratio method to obtain Q0 (Q at 1 Hz) and the frequency correlation factor η corresponding to each path. Based on the results, the distribution images of Q0 and η in 1°×1° grids for Xinjiang region were gained by the back-projection technique. The results indicate that Q0 is high (300-450) in the Tarim platform and marginal Siberian platform, while Q0 is low (150-250) in the southern regions as west Kunlun fold system and Songpan-Ganzi fold system. In the northern regions as Junggar fold system and Tianshan fold system, Q0 is also low (250-300) and η varies between 0.5 and 0.9. 展开更多
关键词 Lg coda Q stacked spectral ratio method back-projection technique xinjiang region
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