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基于Hatch滤波的改进矩阵变换法在BDS多频模糊度解算中的应用
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作者 刘国超 姜凯华 +1 位作者 黄文嘉 张莹 《工程勘察》 2024年第7期49-54,共6页
长基线条件下,空间相关性弱,电离层延迟残差和噪声影响变大,致使矩阵变换法模糊度解算过程中,窄巷组合受噪声影响大,单历元模糊度解算成功率低。因此,削弱电离层残差及噪声影响可以一定程度提高模糊度解算成功率。本文在分析矩阵变换算... 长基线条件下,空间相关性弱,电离层延迟残差和噪声影响变大,致使矩阵变换法模糊度解算过程中,窄巷组合受噪声影响大,单历元模糊度解算成功率低。因此,削弱电离层残差及噪声影响可以一定程度提高模糊度解算成功率。本文在分析矩阵变换算法基础上,利用Hatch滤波有效抑制伪距测量噪声和多径效应特点,结合弱电离层、低噪声的载波组合,通过相位平滑伪距代替组合伪距值参与解算,从而削弱电离层残差及观测噪声影响。通过实测数据分析,本文算法可有效提高矩阵变换法模糊度解算成功率。 展开更多
关键词 模糊度 BDS hatch滤波 矩阵变换 载波相位平滑伪距
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tRNA^(Glu)-derived fragments from embryonic extracellular vesicles modulate bovine embryo hatching
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作者 Yuan Fan Krishna Chaitanya Pavani +2 位作者 Katrien Smits Ann Van Soom Luc Peelman 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1559-1566,共8页
Transfer RNA-derived small RNAs(tsRNAs)have been shown to be involved in early embryo development and repression of endogenous retroelements in embryos and stem cells.However,it is unknown whether tsRNAs also regulate... Transfer RNA-derived small RNAs(tsRNAs)have been shown to be involved in early embryo development and repression of endogenous retroelements in embryos and stem cells.However,it is unknown whether tsRNAs also regulate embryo hatching.In this study,we mined the sequencing data of a previous experiment in which we demonstrated that the microRNA(miRNA)cargo of preimplantation embryonic extracellular vesicles(EVs)influences embryo development.We thus profiled the tsRNA cargo of EVs secreted by blastocysts and non-blastocysts.The majority of tsRNAs was identified as tRNA halves originating from the 5'ends of tRNAs.Among the 148 differentially expressed tsRNAs,the 19 nt tRNA fragment(tRF)tDR-14:32-Glu-CTC-1 was found to be significantly up-regulated in EVs derived from non-blastocysts.RT-qPCR assays confirmed its significant up-regulation in non-blastocyst embryos and their conditioned medium compared to the blastocyst group(P<0.05).Inhibition of tDR-14:32-Glu-CTC-1 by supplementing antagomirs to the conditioned medium improved embryo hatching(P<0.05).Transcriptomic analysis of embryos treated with tDR-14:32-Glu-CTC-1 antagomirs further showed differential expression of genes that are associated with embryo hatching and implantation.In summary,tDR-14:32-Glu-CTC-1 is up-regulated in non-blastocyst embryos and their secretions,and inhibition of tDR-14:32-Glu-CTC-1 promotes embryo hatching,while influencing embryo implantation-related genes and pathways.These results indicate that embryonic EVs containing specific tRFs may regulate preimplantation embryo development. 展开更多
关键词 EMBRYO Extracellular vesicles hatchING tRNA fragments ts RNAs
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HATCH评分、APPLE评分在心房颤动患者射频消融术后复发的预测价值研究
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作者 李晓刚 于颖慧 +2 位作者 李小伟 张璐 何健 《中国循证心血管医学杂志》 2023年第7期843-846,共4页
目的探讨HATCH评分、APPLE评分在心房颤动(房颤)患者射频消融术后复发的预测价值。方法选取2018年5月至2020年6月于秦皇岛市第一医院心血管内科行射频消融术治疗的105例房颤患者的临床资料进行回顾性分析,观察手术时间、X线曝光时间、... 目的探讨HATCH评分、APPLE评分在心房颤动(房颤)患者射频消融术后复发的预测价值。方法选取2018年5月至2020年6月于秦皇岛市第一医院心血管内科行射频消融术治疗的105例房颤患者的临床资料进行回顾性分析,观察手术时间、X线曝光时间、消融成功率及复发率;且根据术后3个月后是否出现持续时间≥30 s的快速性房性心律失常分为复发组(n=36)和未复发组(n=69),分析影响复发的危险因素,评估HATCH评分、APPLE评分及两项联合评估房颤患者术后复发的AUC值、敏感度、特异度。结果105例房颤患者均顺利完成射频消融术,消融成功率为65.71%,复发率为34.29%。复发组与未复发组在性别、年龄、病程、合并高血压、糖尿病、心力衰竭、估算的肾小球滤过率(eGFR)、持续性房颤、左心室大小、左室射血分数(LVEF)、右室前后径、升主动脉内径、肺动脉主干内径、室内隔厚度、左室后壁厚度、主动脉瓣口血流速度、肌酐等资料比较中,差异均无统计学意义(P>0.05);而在左心房大小、E峰、HATCH评分、APPLE评分等比较中,差异具有统计学意义(P<0.05)。二元Logistic回归分析显示,左心房大小、E峰、HATCH评分、APPLE评分是影响手术治疗后复发的独立危险因素(P<0.001)。ROC曲线分析显示,HATCH评分、APPLE评分及两项联合评估房颤患者术后复发的AUC值分别为(0.747、0.807、0.927,P<0.05);敏感度分别为44.40%、69.40%、94.40;特异度分别为91.30%、85.50%、84.10%。结论HATCH评分、APPLE评分预测房颤患者射频消融术后复发具有一定价值,且两项联合有利于提高敏感度,能为识别术后复发提供指导。 展开更多
关键词 hatch评分 APPLE评分 射频消融术 心房颤动 复发
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A super-large graphite deposit discovered in granite rocks at Huangyangshan, Xinjiang,China 被引量:9
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作者 Jiang Ai Xin-biao Lu +1 位作者 Zuo-wu Li Ya-lun Wu 《China Geology》 2018年第1期164-166,共3页
1.Objective A graphite deposit has been discovered in Sujiquan, Xinjiang in 1980s,which provides detailed geological settings for the super-large graphite deposit discovered in Huangyangshan pluton with total reserves... 1.Objective A graphite deposit has been discovered in Sujiquan, Xinjiang in 1980s,which provides detailed geological settings for the super-large graphite deposit discovered in Huangyangshan pluton with total reserves up to 7.264×10^9 t in 2017.Outcrops of igneous rocks in the study area include Middle Devonian plagioclase granite and Late Carboniferous alkali feldspar granite that is referred to the Huangyangshan pluton,which includes the Lower Carboniferous Heishantou Formation and Jiangbasi Formation,both of which consist of volcanic-sedimentary rocks (Fig.1).Sujiquan fault provided passage for the migration of volcanic intrusions.Graphite deposits are usually hosted by metamorphic rocks,but Huangyanshan deposits are hosted by granite rocks,which are rarely known.The Huangyangshan graphite deposit hosted by granite pluton at Huangyangshan area was discovered by Xinjiang Branch of China National Geological Exploration Center of Building Materials Industry since 2015. 展开更多
关键词 super-large GRAPHITE DEPOSIT GRANITE ROCKS Huangyangshan
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Numerical simulation research on response characteristics of surrounding rock for deep super-large section chamber under dynamic and static combined loading condition 被引量:13
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作者 FAN De-yuan LIU Xue-sheng +3 位作者 TAN Yun-liang SONG Shi-lin NING Jian-guo MA Qing 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第12期3544-3566,共23页
The stability control of surrounding rock for large or super-large section chamber is a difficult technical problem in deep mining condition.Based on the in-site geological conditions of Longgu coal mine,this paper us... The stability control of surrounding rock for large or super-large section chamber is a difficult technical problem in deep mining condition.Based on the in-site geological conditions of Longgu coal mine,this paper used the dynamic module of FLAC3D to study the response characteristics of deep super-large section chamber under dynamic and static combined loading condition.Results showed that under the static loading condition,the maximum vertical stress,deformation and failure range are large,where the stress concentration coefficient is 1.64.The maximum roof-to-floor and two-sides deformations are 54.6 mm and 53.1 mm,respectively.Then,under the dynamic and static combined loading condition:(1)The influence of dynamic load frequency on the two-sides is more obvious;(2)The dynamic load amplitude has the greatest influence on the stress concentration degree,and the plastic failure tends to develop to the deeper;(3)With the dynamic load source distance increase,the response of surrounding rock is gradually attenuated.On this basis,empirical equations for each dynamic load conditions were obtained by using regression analysis method,and all correlation coefficients are greater than 0.99.This research provided reference for the supporting design of deep super-large section chamber under same or similar conditions. 展开更多
关键词 deep mining super-larger section chamber static load dynamic load frequency dynamic load amplitude dynamic load source distance
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Bainiuchang super-large silver-polymetallic ore deposit related to granitic magmatism in Mengzi, Yunnan 被引量:4
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作者 刘继顺 张洪培 +1 位作者 欧阳玉飞 张彩华 《Journal of Central South University of Technology》 EI 2007年第4期568-574,共7页
Bainiuchang silver-polymetallic ore deposit is located in the southeast Yunnan tin-polymetallic metallogenic belt.The probable reserves and inferred resources of the deposit are of 6 470 t Ag and 1.10 Mt Pb and 1.72 M... Bainiuchang silver-polymetallic ore deposit is located in the southeast Yunnan tin-polymetallic metallogenic belt.The probable reserves and inferred resources of the deposit are of 6 470 t Ag and 1.10 Mt Pb and 1.72 Mt Zn and 86 kt Sn.Orebodies of the deposit occur in clastic-carbonate rocks of Tianpeng Formation and Longha Formation of the middle Cambrian System above the Bainiuchang concealed granite of the late Yanshan period.The concealed granite has the characteristics of tin-bearing granites.Abundance of the mineralization elements Sn,Cu,Zn,Pb,Ag and Sb is high in the granitic rocks.Sulphur isotope data of the metal sulphides indicate that most sulphur is derived from the magmas.The ores are similar in rare earth element(REE)patterns to the granitic rocks.The granitic magma activity results in ore-bearing structures.Rocks of the Middle Cambrian System above the concealed intrusion suffer from skarnization,hornfelsing,marbleization,siliconizing and carbonatization.The mineralization elements Sn,Cu,Zn,Pb,Ag and Sb successively appear from the top of the granite to surrounding rocks.These evidences indicate that the granitic magmatism is the principal mineralization factor.The opinion that the south Bainiuchang ore field and the north Awei ore block are tin and copper potential exploration areas was put forward and was verified by drilling tests. 展开更多
关键词 BAINIUCHANG super-large silver-polymetallic deposit granite granitic-porphyry tin ore
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Instability energy mechanism of super-large section crossing chambers in deep coal mines 被引量:3
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作者 Deyuan Fan Xuesheng Liu +2 位作者 Yunliang Tan Xuebin Li Purev Lkhamsuren 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第5期1075-1086,共12页
The stress concentration and failure at chamber intersections in coal mine are intense,especially in deepburied,super-large section conditions.In this paper,the plastic radius of super-large section chamber under uneq... The stress concentration and failure at chamber intersections in coal mine are intense,especially in deepburied,super-large section conditions.In this paper,the plastic radius of super-large section chamber under unequal pressure was corrected on the basis of the size effect.Then,stress and failure evolution of intersections under different crossing angles and equivalent angular bisectors were revealed.Furthermore,2 trajectory curves of failure and stress were analytically expressed,which divided the intersection into 5 influencing zones in the light of stress superposition degree.After determining instability trigger point and instability path,instability energy criterion of intersection can be obtained as K>1,which means that the external energy is greater than the sum of energy consumed by surrounding rock instability and supporting structure failure.Taking coal-gangue separation system of Longgu Coal Mine as example,it was found that there was instability risk under original parameters.For long-term stability,an optimization design method was proposed by considering safety factor,and optimal support scheme was obtained.Field monitoring showed intersections deformations were relatively small with the maximum of 125 mm,which verified the rationality of theoretical analysis.This study provides guidance for the stability control of the intersections under the same or similar conditions. 展开更多
关键词 super-large section INTERSECTION Instability energy mechanism Optimization design Field monitoring
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New Zircon U-Pb Age of the Super-Large Lijiagou Spodumene Deposit in Songpan Garze Fold Belt, Eastern Tibet: Implications for Early Jurassic Rare-Metal Polymetallic Event 被引量:8
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作者 FEI Guangchun TIAN Jingjing +4 位作者 YANG Jiyi GAO Jianguo TANG Wenchun LI Jian GU Chenghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第3期1274-1275,共2页
Objective The Songpan-Garze Fold Belt(SGFB),located in the eastern part of the Tibet Plateau and west of the Sichuan Basin,is an important pegmatite province in China.Some famous pegmatite type deposits occur in the S... Objective The Songpan-Garze Fold Belt(SGFB),located in the eastern part of the Tibet Plateau and west of the Sichuan Basin,is an important pegmatite province in China.Some famous pegmatite type deposits occur in the SGFB,including the Xuebaoding,Jiajika,Keeryin rare metal deposits and Danba muscovite deposit(Li Jiankang et al.,2015).The newly discovered super-large Lijiagou 展开更多
关键词 New Zircon U-Pb Age of the super-large Lijiagou Jurassic Rare-Metal Polymetallic Event
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Wind-induced responses of super-large cooling towers 被引量:3
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作者 柯世堂 葛耀君 +2 位作者 赵林 陈少林 Y.Tamura 《Journal of Central South University》 SCIE EI CAS 2013年第11期3216-3228,共13页
Traditional gust load factor(GLF)method,inertial wind load(IWL)method and tri-component method(LRC+IWL)cannot accurately analyze the wind-induced responses of super-large cooling towers,so the real combination formula... Traditional gust load factor(GLF)method,inertial wind load(IWL)method and tri-component method(LRC+IWL)cannot accurately analyze the wind-induced responses of super-large cooling towers,so the real combination formulas of fluctuating wind-induced responses and equivalent static wind loads(ESWLSs)were derived based on structural dynamics and random vibration theory.The consistent coupled method(CCM)was presented to compensate the coupled term between background and resonant response.Taking the super-large cooling tower(H=215 m)of nuclear power plant in Jiangxi Province,China,which is the highest and largest in China,as the example,based on modified equivalent beam-net design method,the aero-elastic model for simultaneous pressure and vibration measurement of super-large cooling tower is firstly carried out.Then,combining wind tunnel test and CCM,the effects of self-excited force on the surface pressures and wind-induced responses are discussed,and the wind-induced response characteristics of background component,resonant component,coupled term between background and resonant response,fluctuating responses,and wind vibration coefficients are discussed.It can be concluded that wind-induced response mechanism must be understood to direct the wind resistant design for super-large cooling towers. 展开更多
关键词 super-large cooling towers wind-induced responses wind vibration coefficients aero-elastic model consistent coupled method
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A Super-Large Rb-Nb Rare Metal Deposit has been Discovered in Huashi Village of Xinglong County, Hebei Province 被引量:2
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作者 LI Yujing XIE Wu +3 位作者 QI Yunfei MIAO Qunfeng XIONG Chao GONG Chuanwei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期2344-2345,共2页
Objective The Huashi Village in Xinglong County of Hebei Province is located in the Yanshan subsidence zone in the central eastern North China Plate, which is 137 km away from Beijing City (Fig. la). This area has ... Objective The Huashi Village in Xinglong County of Hebei Province is located in the Yanshan subsidence zone in the central eastern North China Plate, which is 137 km away from Beijing City (Fig. la). This area has undergone large -scale magmatic intrusion affected by the tectonic compression of the Pacific Plate in the Mesozoic (known as the Yanshanian movement) to form many alkaline rocks such as the Wulingshan rock mass. Previous studies have conducted petrological research and reconnaissance survey of rare metal ores in this area (Tian Shuzhang and Guo Zongshan, 1981; Xu Baoling et al., 1996). In 2016, the Qinhuangdao Mineral and Hydrology Engineering Geological Brigade of Hebei Bureau of Geology and Mineral Resources Exploration implemented the project of Reconnaissance of Rare Metal Ores Including Rubidium in Huashi Village of Xinglong County, Hebei Province, and discovered super-large rare metal deposits of rubidium and biobium in the Madi alkali feldspar granite bodies in the Huashi Village to achieve great breakthrough of rare metal ore prospecting. 展开更多
关键词 A super-large Rb-Nb Rare Metal Deposit Huashi
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Two Super-Large Gold Deposits Have Been Discovered in Jiaodong Peninsula of China 被引量:3
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作者 HAO Ziguo FEI Hongcai +1 位作者 HAO Qingqing LIU Lian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期368-369,共2页
During 2015, gold prospecting in Laizhou City of Shandong Peninsula in China has achieved a major breakthrough. Deposits containing 470 and 389 tons of gold metal were discovered in the northern sea area of Sanshandao... During 2015, gold prospecting in Laizhou City of Shandong Peninsula in China has achieved a major breakthrough. Deposits containing 470 and 389 tons of gold metal were discovered in the northern sea area of Sanshandao and the Shaling area, respectively. As a result, the gold prospective resources in the entire Jiaodong Peninsula have now exceeded 4000 tons, fully indicative of the super-large prospecting potential of the Jiaojia-type deposits. 展开更多
关键词 GOLD Two super-large Gold Deposits Have Been Discovered in Jiaodong Peninsula of China
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Magmatic Evolution and Mineralization Process of the Super-Large Shihuiyao Rb–Nb–Ta Deposit,Southern Great Xing'an Range,China 被引量:3
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作者 ZHOU Zhenhua CHE Hewei +1 位作者 MA Xinghua GAO Xu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第6期2275-2276,共2页
Rare metal ore reserves are an important strategic resource, and their metallogenic mechanism and mineralization studies have also been received widespread international attention.
关键词 In Nb Magmatic Evolution and Mineralization Process of the super-large Shihuiyao Rb Ta Deposit Southern Great Xing’an Range China
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The Major Ore Clusters of Super-Large Iron Deposits in the World, Present Situation of Iron Resources in China, and Prospect 被引量:2
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作者 ZHAO Yiming FENG Chengyou LI Daxin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第6期1895-1915,共21页
The metamorphosed sedimentary type of iron deposits(BIF) is the most important type of iron deposits in the world, and super-large iron ore clusters of this type include the Quadrilatero Ferrifero district and Caraj... The metamorphosed sedimentary type of iron deposits(BIF) is the most important type of iron deposits in the world, and super-large iron ore clusters of this type include the Quadrilatero Ferrifero district and Carajas in Brazil, Hamersley in Australia, Kursk in Russia, Central Province of India and Anshan-Benxi in China. Subordinated types of iron deposits are magmatic, volcanic-hosted and sedimentary ones. This paper briefly introduces the geological characteristics of major super-large iron ore clusters in the world. The proven reserves of iron ores in China are relatively abundant, but they are mainly low-grade ores. Moreover, a considerate part of iron ores are difficult to utilize for their difficult ore dressing, deep burial or other reasons. Iron ore deposits are relatively concentrated in 11 metallogenic provinces(belts), such as the Anshan-Benxi, eastern Hebei, Xichang-Central Yunnan Province and middle-lower reaches of Yangtze River. The main minerogenetic epoches vary widely from the Archean to Quaternary, and are mainly the Late Archean to Middle Proterozoic, Variscan, and Yanshanian periods. The main 7 genetic types of iron deposits in China are metamorphosed sedimentary type(BIF), magmatic type, volcanic-hosted type, skarn type, hydrothermal type, sedimentary type and weathered leaching type. The iron-rich ores occur predominantly in the skarn and marine volcanic-hosted iron deposits, locally in the metamorphosed sedimentary type(BIF) as hydrothermal reformation products. The theory of minerogenetic series of mineral deposits and minerogenic models has applied in investigation and prospecting of iron ore deposits. A combination of deep analyses of aeromagnetic anomalies and geomagnetic anomalies, with gravity anomalies are an effective method to seeking large and deep-buried iron deposits. China has a relatively great oresearching potential of iron ores, especially for metamorphosed sedimentary, skarn, and marine volcanic-hosted iron deposits. For the lower guarantee degree of iron and steel industry, China should give a trading and open the foreign mining markets. 展开更多
关键词 major ore clusters of super-large iron deposits present situation of iron ore resources in China genetic type temporal-spatial distribution ore-searching potential
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Application of Tectono Geochemical Study in Deep Concealed Ore Body Exploration--As the Huize Super-Large Lead-Zinc Deposit an exemple 被引量:1
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作者 ZHANG Quan GUO Yuxinyue +1 位作者 PU Chuanjie WANG Feng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期247-248,共2页
1 Geological Background of Minerlization or Geologic Setting The northeast of Yunnan1 Pb-Zn-Ag-Ge polymetallic ore district is an important part of the southwestern margin of the Yangtze block Sichuan-Yunnan-Guizhou
关键词 Application of Tectono Geochemical Study in Deep Concealed Ore Body Exploration NE As the Huize super-large Lead-Zinc Deposit an exemple MVT
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Source of the Ore-forming Adakitic Porphyry at the Beiya Super-large Au Deposit, Western Yangtze Craton: New Evidence from Zircon U-Pb Ages of the Amphibolite Xenoliths
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作者 LIU Siqi ZHENG Yuanchuan +3 位作者 SHEN Yang HOU Zengqian WANG Lu WANG Zixuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第1期208-209,共2页
Objective The Beiya super-large Au-rich porphyry deposit(304 t Au,2.4 g/t Au)is located within the western Yangtze craton,to the southeast of the Sanjiang Tethyan Orogen(Fig.1).The ore-forming porphyry is adakitic,cha... Objective The Beiya super-large Au-rich porphyry deposit(304 t Au,2.4 g/t Au)is located within the western Yangtze craton,to the southeast of the Sanjiang Tethyan Orogen(Fig.1).The ore-forming porphyry is adakitic,characterized by high Sr/Y and La/Yb ratios coupled with low Y and Yb contents,and is generally thought to be derived from partial melting of thickened mafic lower crust.The lower crust underneath the western Yangtze craton is mainly composed of ancient crust with Archean ages,juvenile crust resulting from the Neoproterozoic subduction(740–1000 Ma),and late Permian juvenile crust related to the Emeishan mantle plume.Which lower crustal end-member has played a critical role in genesis of the Beiya ore-forming porphyry can be constrained by zircon U-Pb ages of amphibolite xenoliths hosted in the ore-forming porphyry,because these xenoliths represent direct samples of the source.In this study,we present new zircon U-Pb ages of these amphibolite xenoliths to have insight into the nature of the Beiya adakitic porphyry source. 展开更多
关键词 Western Yangtze Craton New Evidence from Zircon U-Pb Ages of the AMPHIBOLITE XENOLITHS Source of the ORE-FORMING Adakitic PORPHYRY at the Beiya super-large Au DEPOSIT
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Super-Large Pb-Zn Deposits Discovered in Danaopo,Huayuan County,Hunan Province
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作者 HAO Ziguo FEI Hongcai +1 位作者 HAO Qingqing LIU Lian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第2期672-673,共2页
Geological Brigade 405 of Hunan Provincial Geology and Mineral Exploration and Development Bureau discovered the Danaopo and Yangjiazhai super-large Pb- Zn deposits through 5 years (2009-2014) of exploration in Huay... Geological Brigade 405 of Hunan Provincial Geology and Mineral Exploration and Development Bureau discovered the Danaopo and Yangjiazhai super-large Pb- Zn deposits through 5 years (2009-2014) of exploration in Huayuan County, Hunan Province. These deposits contain 208.4942 million tons of (332+333) class Pb+Zn ores and 4.8746 million tons of metal amounts, of which metal amounts of 333 class zinc are 4.1198 million tons and metal amounts of lead are 0.7548 million tons, associated with useful components of Cd, Ag and Se. In addition, the Limei, Qingshuitang and Yutang Pb-Zn deposits were proven betbre and this region has thus been ranked as a Pb-Zn ore resource base with a hundred-ton scale (Fig. 1). 展开更多
关键词 PB super-large Pb-Zn Deposits Discovered in Danaopo Huayuan County Hunan Province Zn
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Breeding of Super-large-grain Wheat Germplasms
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作者 Zhanliang YANG Xiaoli BAO +2 位作者 Yongshun XU Qiaoxu CHU Fangyun CHU 《Agricultural Biotechnology》 CAS 2022年第5期22-25,33,共5页
[Objectives]This study was conducted to breed high-yielding wheat varieties. [Methods] A new breeding technology of "Artificial mutagenesis to increase genetic differences between parents and to enhance heterosis... [Objectives]This study was conducted to breed high-yielding wheat varieties. [Methods] A new breeding technology of "Artificial mutagenesis to increase genetic differences between parents and to enhance heterosis" was put forward. Longnan 71 a and Longnan 71 a mutants bred by this technology were crossed with other mutants and normal materials. [Results] In the Wudu experimental field of Longnan City, the traits of super-large grain appeared in the obverse and inverse cross with Longnan 71 a as parents. The trait of super-large grain was dominantly inherited. The traits of various combinations in the Fgeneration were segregated. In the Fgeneration, one super-large-grain low-stalk line and other lines with specific traits were selected. In the Fgeneration, two super-large-grain low-stalk large-ear lines were selected. These three super-large-grain low-stalk wheat lines had reduced plant height and good lodging resistance, and possessed two high-yielding characters among the three factors of yield, so they were expected to be further bred into high-yielding wheat varieties. One line with the largest grain length of 10.3 mm was selected in the Fgeneration. After two years of breeding, in 2022, the largest grain length was measured to be 10.6 mm, and the average 1 000-grain weight and the largest 1 000-grain weight were 75.8 and 100 g, respectively. [Conclusions] This study is about the major progress in artificial cultivation of super-large-grain wheat and has considerable practical value. 展开更多
关键词 Artificially induced mutation Malformed mutation Genetic difference HYBRIDIZATION super-large grain
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Super-Large Manganese Deposits Have Been Discovered at Pujue and Taoziping,Songtao County in Guizhou Province
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作者 HAO Ziguo FEI Hongcai +1 位作者 HAO Qingqing LIU Lian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第1期343-344,共2页
In 2016,the Geological Brigade No.103 of Guizhou Geology and Mineral Exploration and Development Bureau discovered two super-large manganese deposits at Pujue and Taoziping,in Songtao County,Guizhou Province(Fig.1).... In 2016,the Geological Brigade No.103 of Guizhou Geology and Mineral Exploration and Development Bureau discovered two super-large manganese deposits at Pujue and Taoziping,in Songtao County,Guizhou Province(Fig.1).The Pujue manganese deposit has191.59 million tons of proven(332+333)class ore reserves,including 35.54 million tons of 332 class and 展开更多
关键词 super-large Manganese Deposits Have Been Discovered at Pujue and Taoziping Songtao County in Guizhou Province
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The Newly Discovered Super-Large Wulashan-Hademengou Gold Metallogenic Belt in Inner Mongolia,China Has Gold Reserves of Over 100 Tons
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作者 HAO Ziguo FEI Hongcai +1 位作者 HAO Qingqing Susan TURNER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第4期1332-1333,共2页
The Wulashan-Hademengou gold ore district in Baotou city, Inner Mongolia, is a further newly discovered super-large gold metallogenic belt in northern China. The accumulated proven gold metal amount is 84.46 t, with a... The Wulashan-Hademengou gold ore district in Baotou city, Inner Mongolia, is a further newly discovered super-large gold metallogenic belt in northern China. The accumulated proven gold metal amount is 84.46 t, with an average grade of 3.53 g/t and a gold metal amount of 63.16 t, with an average grade of 3.30 g/t. The potential reserves are over 100 t. 展开更多
关键词 Gold The Newly Discovered super-large Wulashan-Hademengou Gold Metallogenic Belt in Inner Mongolia China Has Gold Reserves of Over 100 Tons
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基于Hatch载波相位平滑算法的Galileo双频精密单点定位性能研究
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作者 彭嘉浚 石迪迪 王沁 《测绘与空间地理信息》 2023年第3期138-141,共4页
为评估Hatch载波相位平滑算法对精密单点精度的影响,以多个MGEX跟踪站数据为解算数据,进行了滤波前后Galileo双频精密单点定位解算实验。实验结果表明,E1/E5a、E1/E5b双频组合精密单点定位精度可以达到厘米级,而E5a/E5b双频组合精密单... 为评估Hatch载波相位平滑算法对精密单点精度的影响,以多个MGEX跟踪站数据为解算数据,进行了滤波前后Galileo双频精密单点定位解算实验。实验结果表明,E1/E5a、E1/E5b双频组合精密单点定位精度可以达到厘米级,而E5a/E5b双频组合精密单点定位精度较差,不适合进行组合定位。Hatch载波相位平滑算法能在一定程度上提升Galileo双频精密单点定位精度,但提升程度较小,提升量都在10%以内。 展开更多
关键词 hatch载波相位平滑算法 GALILEO 双频 精密单点定位
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