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Upper and Lower Bounds of the α-Universal Triple I Method for Unified Interval Implications
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作者 Yiming Tang Jianwei Gao Yifan Huang 《Computers, Materials & Continua》 SCIE EI 2024年第4期1063-1088,共26页
Theα-universal triple I(α-UTI)method is a recognized scheme in the field of fuzzy reasoning,whichwas proposed by our research group previously.The robustness of fuzzy reasoning determines the quality of reasoning al... Theα-universal triple I(α-UTI)method is a recognized scheme in the field of fuzzy reasoning,whichwas proposed by our research group previously.The robustness of fuzzy reasoning determines the quality of reasoning algorithms to a large extent,which is quantified by calculating the disparity between the output of fuzzy reasoning with interference and the output without interference.Therefore,in this study,the interval robustness(embodied as the interval stability)of theα-UTI method is explored in the interval-valued fuzzy environment.To begin with,the stability of theα-UTI method is explored for the case of an individual rule,and the upper and lower bounds of its results are estimated,using four kinds of unified interval implications(including the R-interval implication,the S-interval implication,the QL-interval implication and the interval t-norm implication).Through analysis,it is found that theα-UTI method exhibits good interval stability for an individual rule.Moreover,the stability of theα-UTI method is revealed in the case of multiple rules,and the upper and lower bounds of its outcomes are estimated.The results show that theα-UTI method is stable for multiple rules when four kinds of unified interval implications are used,respectively.Lastly,theα-UTI reasoning chain method is presented,which contains a chain structure with multiple layers.The corresponding solutions and their interval perturbations are investigated.It is found that theα-UTI reasoning chain method is stable in the case of chain reasoning.Two application examples in affective computing are given to verify the stability of theα-UTImethod.In summary,through theoretical proof and example verification,it is found that theα-UTImethod has good interval robustness with four kinds of unified interval implications aiming at the situations of an individual rule,multi-rule and reasoning chain. 展开更多
关键词 Fuzzy reasoning the CRI method the triple I method fuzzy implication interval robustness
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Depositional model of the Member Deng-2 marginal microbial mound-bank complex of the Dengying Formation in the southwestern Sichuan Basin, SW China: Implications for the Ediacaran microbial mound construction and hydrocarbon exploration
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作者 Jin-Min Song Xin Jin +10 位作者 Zhong Luo Shu-Gen Liu Shao-Bo Liu Xing-Zhi Ma Zhi-Wu Li Xue-Song Lu Ling-Li Zhao Ke-Ran Li Jia-Xin Ren Li-Zhou Tian Hao-Shuang Deng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期806-822,共17页
Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional p... Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional process is regarded confusing. The microfacies, construction types, and depositional model of the Member Deng-2 marginal microbial mound-bank complex have been investigated using unmanned aerial vehicle photography, outcrop section investigation, thin section identification,and seismic reflections in the southwestern Sichuan Basin. The microbialite lithologic textures in this region include thrombolite, dendrolite, stromatolite, fenestral stromatolite, spongiostromata stone,oncolite, aggregated grainstone, and botryoidal grapestone. Based on the comprehensive analysis of“depositional fabrics-lithology-microfacies”, an association between a fore mound, mound framework,and back mound subfacies has been proposed based on water depth, current direction, energy level and lithologic assemblages. The microfacies of the mound base, mound core, mound flank, mound cap, and mound flat could be recognized among the mound framework subfacies. Two construction types of marginal microbial mound-bank complex have been determined based on deposition location, mound scale, migration direction, and sedimentary facies association. Type Jinkouhe microbial mound constructions(TJMMCs) develop along the windward margin owing to their proximity to the seaward subfacies fore mound, with a northeastwardly migrated microbial mound on top of the mud mound,exhibiting the characteristics of large-sized mounds and small-sized banks in the surrounding area. Type E'bian microbial mound constructions(TEMMCs) primarily occur on the leeward margin, resulting from the presence of onshore back mound subfacies, with the smaller southwestward migrated microbial mounds existing on a thicker microbial flat. The platform margin microbial mound depositional model can be correlated with certain lateral comparison profile and seismic reflection structures in the 2D seismic section, which can provide references for future worldwide exploration. Microbial mounds with larger buildups and thicker vertical reservoirs are typically targeted on the windward margin, while small-sized microbial mounds and flats with better lateral connections are typically focused on the leeward margin. 展开更多
关键词 Sichuan Basin The Member Deng-2 Marginal microbial mound-bank complex Depositional model Exploration implications
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Discussion on the Implications of Expansion in Postgraduate Education
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作者 Jingyu Zhu 《Journal of Contemporary Educational Research》 2024年第6期128-134,共7页
This paper explores the development of postgraduate education in China,including the overall situation of postgraduate education,the trend in enrollment expansion in professional degrees as well as in various academic... This paper explores the development of postgraduate education in China,including the overall situation of postgraduate education,the trend in enrollment expansion in professional degrees as well as in various academic fields;it also triggers the impact and discussion about the postgraduate enrollment expansion,such as over-education and credential inflation,as well as the concerns about the quality of education and talent cultivation and so forth.Although the expansion brings various problems,the challenges may also become new opportunities for higher education reform,this paper also provides some suggestions on the expansion of postgraduate education. 展开更多
关键词 Expansion of postgraduate education OVER-EDUCATION Credential inflation implications Employment crisis Education quality
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An Analysis of the Requesting Performance by an EFL Student and Its Pedagogical Implications
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作者 唐磊 江晓敏 《海外英语》 2013年第15期93-94,共2页
The present study investigated one Chinese college learner's requesting performance by analyzing the DCT data produced in four different situations.The results indicated that the learner favored the indirect strat... The present study investigated one Chinese college learner's requesting performance by analyzing the DCT data produced in four different situations.The results indicated that the learner favored the indirect strategy in all four situations,and was able to produce longer requests with a large portion of external modification.However,the learner lacked sufficient knowledge and ability to control over a wide range of internal modification,relied heavily on external modification,produced lengthy grounders,and failed to show enough sensitivity to imposition variation. 展开更多
关键词 requesting PERFORMANCE EFL LEARNER ANALYSIS implic
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On the Principal Constructions to Express the Future Time and Their Implications
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作者 朱虹 《海外英语》 2019年第13期256-257,共2页
According to the definition of tense,English has no actual future tense.The ways to express future time in English vary with the specific situation.We should avoid frequently using the same way to express the future.I... According to the definition of tense,English has no actual future tense.The ways to express future time in English vary with the specific situation.We should avoid frequently using the same way to express the future.It is important to study the different construction of the future time in English and its implications in order to make it clear that the appropriate construction to cope with the specific situation should be noticed. 展开更多
关键词 FUTURE CONSTRUCTIONS implicATION of FUTURE CONSTRUCTIONS
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Determination of the Neoproterozoic Shicaogou Syn-collisional Granite in the Eastern Qinling Mountains and Its Geological Implications 被引量:21
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作者 CHENDanling LIULiang +4 位作者 SUNYong ZHANGAnda ZHANGChengli LIUXiaoming LUOJinhai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期73-82,共10页
The Shicaogou granite has been identified as a magnesian (Fe-number=0.71-0.76), calcic to calc-alkalic (MALI=3.84-5.76) and peraluminous (ASI=1.06-1.13) granite of the syn-collisional S-type, with high SiO2(>71%), ... The Shicaogou granite has been identified as a magnesian (Fe-number=0.71-0.76), calcic to calc-alkalic (MALI=3.84-5.76) and peraluminous (ASI=1.06-1.13) granite of the syn-collisional S-type, with high SiO2(>71%), A12O3 (>13%) and Na2O+K2O (6.28%-7.33%, equal for NaO2 and K2O). Trace element and REE analyses show that the granite is rich in LILE such as of Rb, Sr, Ba and Th, and poor in HFSE like Yb, Y, Zr and Hf. Its Rb/Sr ratio is greater than 1; the contents of Nb and Ta, and the ratio of Nb/Ta as well as the REE geochemical features (e.g. REE abundance, visible fractionation of LREE and HREE and medium to pronounced negative Eu anomalies) are all similar to those of crust-origin, continent-continent syn-collisional granite. Moreover, the granite exhibits almost the same pattern as that of the typical continent-continent syn-collisional granite on the spider diagram and all samples fall within the syn-collisional granite field.The cathodoluminescence (CL) investigations have revealed that the zircon from the Shicaogou granite represents a typical magmatic product characterized by its colorless, transparent and euhedral crystals, and distinct zoning of oscillatory bands. Residual cores of irregular zircon can be found in a few enhedral grains. Trace element studies of the zircon grains, with high contents of P, Y, Hf, Th, U and REE and high ratios of Th/U, obviously positive Ce anomalies and HREE enrichment compared to LREE, also result in the same conclusion.The LA-ICP-MS U-Pb isotopic data from 24 spots of 21 zircon grains demonstrate that 20 spots in the oscillatory zone yield an average weighted 206Pb/238U age of 925±11 Ma, indicating that the Shicaogou granite was formed in the Neoproterozoic. Combined with other Neoproterozoic syn-collisional granites found in the study area, the present geochronological determination can further reveal that collision-amalgamation events could have occurred among some continental blocks in the Qinling orogenic belt during the Neoproterozoic. This in turn provides an accurate chronological constraint on the Neoproterozoic break-up and convergence in the belt. 展开更多
关键词 LA-ICP-MS U-Pb dating ZIRCON syn-collisional S-type granite geological implication Shicaogou eastern Qinling Mountains
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2.7 Ga Monzogranite on the Songnen Massif and Its Geological Implications 被引量:13
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作者 WU Xinwei ZHANG Chao +6 位作者 ZHANG Yujin GUO Wei ZHANG Chao CUI Tianri YANG Yajun HU Jianfei SONG Wanbing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第3期1265-1266,共2页
Objective The formation and evolution of Songnen massif has always been a hot topic,and the presence of Precambrian basement on the Songnen massif is still controversial:(1)Lacking of Pre-Paleozoic dating results,the ... Objective The formation and evolution of Songnen massif has always been a hot topic,and the presence of Precambrian basement on the Songnen massif is still controversial:(1)Lacking of Pre-Paleozoic dating results,the Precambrian basement on Songnen massif does not extend largely according to the isotopic dating results of core from basement,(2)the existence of gneiss from deep drill holes 展开更多
关键词 the Songnen Massif Its Geological implications Ga Monzogranite
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Chemical and Isotopic Characteristics of the Water and Suspended Particulate Materials in the Yangtze River and Their Geological and Environmental Implications 被引量:10
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作者 DING Tiping GAO Jianfei +5 位作者 TIAN Shihong SHI Guoyu CHEN Feng WANG Chengyu LUO Xurong HAN Dan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第1期276-360,共85页
The chemical and isotopic characteristics of the water and suspended particulate materials(SPM) in the Yangtze River were investigated on the samples collected from 25 hydrological monitoring stations in the mainste... The chemical and isotopic characteristics of the water and suspended particulate materials(SPM) in the Yangtze River were investigated on the samples collected from 25 hydrological monitoring stations in the mainsteam and 13 hydrological monitoring stations in the major tributaries during 2003 to 2007. The water samples show a large variation in both δD( 30‰ to 112‰) and δ18O( 3.8‰ to 15.4‰) values. Both δD and δ18O values show a decrease from the river head to the Jinsha Jiang section and then increase downstream to the river mouth. It is found that the oxygen and hydrogen isotopic compositions of the Yangtze water are controlled by meteoric precipitation, evaporation, ice(and snow) melting and dam building. The Yangtze SPM concentrations show a large variation and are well corresponded to the spatial and temporal changes of flow speed, runoff and SPM supply, which are affected by the slope of the river bed, local precipitation rate, weathering intensity, erosion condition and anthropogenic activity. The Yangtze SPM consists of clay minerals, clastic silicate and carbonate minerals, heavy minerals, iron hydroxide and organic compounds. From the upper to lower reaches, the clay and clastic silicate components in SPM increase gradually, but the carbonate components decrease gradually, which may reflect changes of climate and weathering intensity in the drainage area. Compared to those of the upper crust rocks, the Yangtze SPM has lower contents of SiO2, CaO, K2 O and Na2 O and higher contents of TFe2 O3 and trace metals of Co, Ni, Cu, Zn, Pb and Cd. The ΣREE in the Yangtze SPM is also slightly higher than that of the upper crust. From the upper to lower reaches, the CaO and MgO contents in SPM decrease gradually, but the SiO2 content increases gradually, corresponding to the increase of clay minerals and decrease of the carbonates. The δ30SiSPM values( 1.1‰ to 0.3‰) of the Yangtze SPM are similar to those of the average shale, but lower than those of the granite rocks( 0.3‰ to 0.3‰), reflecting the effect of silicon isotope fractionation in silicate weathering process. The δ30SiSPM values of the Yangtze SPM show a decreasing trend from the upper to the middle and lower reaches, responding to the variation of the clay content. The major anions of the river water are HCO 3, SO 4 2, Cl, NO 3, SiO 4 4 and F and the major cations include Ca2+, Na+, Mg2+, K+ and Sr2+. The good correlation between HCO3-content and the content of Ca2+may suggest that carbonate dissolution is the dominate contributor to the total dissolved solid(TDS) of the Yangtze River. Very good correlations are also found among contents of Cl, SO4 2, Na+, Mg2+, K+and Sr2+, indicating the important contribution of evaporite dissolution to the TDS of the Yangtze River. High TDS contents are generally found in the head water, reflecting a strong effect of evaporation in the Qinghai-Tibet Plateau. A small increase of the TDS is generally observed in the river mouth, indicating the influence of tidal intrusion. The F and NO3 contents show a clear increase trend from the upstream to downstream, reflecting the contribution of pesticides and fertilizers in the Chuan Jiang section and the middle and lower reaches. The DSi shows a decrease trend from the upstream to downstream, reflecting the effect of rice and grass growth along the Chuan Jiang section and the middle and lower reaches. The dissolved Cu, Zn and Cd in the Yangtze water are all higher than those in world large rivers, reflecting the effect of intensive mining activity along the Yangtze drainage area. The Yangtze water generally shows similar REE distribution pattern to the global shale. The δ30SiDiss values of the dissolved silicon vary from 0.5‰ to 3.7‰, which is the highest among those of the rivers studied. The δ30SiDiss values of the water in the Yangtze mainsteam show an increase trend from the upper stream to downstream. Its DSi and δ30SiDiss are influenced by multiple processes, such as weathering process, phytolith growth in plants, evaporation, phytolith dissolution, growth of fresh water diatom, adsorption and desorption of aqueous monosilicic acid on iron oxide, precipitation of silcretes and formation of clays coatings in aquifers, and human activity. The δ34SSO4 values of the Yangtze water range from 1.7‰ to 9.0‰. The SO4 in the Yangtze water are mainly from the SO4 in meteoric water, the dissolved sulfate from evaporite, and oxidation of sulfide in rocks, coal and ore deposits. The sulfate reduction and precipitation process can also affect the sulfur isotope composition of the Yangtze water. The87Sr/86Sr ratios of the Yangtze water range from 0.70823 to 0.71590, with an average value of 0.71084. The87Sr/86Sr ratio and Sr concentration are primary controlled by mixing of various sources with different87Sr/86Sr ratios and Sr contents, including the limestone, evaporite and the silicate rocks. The atmospheric precipitation and anthropogenic inputs can also contribute some Sr to the river. The δ11B values of the dissolved B in the Yangtze water range from 2.0‰ to 18.3‰, which is affected by multifactors, such as silicate weathering, carbonate weathering, evaporite dissolution, atmospheric deposition, and anthropogenic inputs. 展开更多
关键词 Yangtze River stable isotopes water chemistry Suspended Particulate Materials(SPM) HYDROLOGY environmental implication
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Implications of periostin in the development of subarachnoid hemorrhage-induced brain injuries 被引量:9
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作者 Hirofumi Nishikawa Hidenori Suzuki 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第12期1982-1984,共3页
Target of research in subarachnoid hemorrhage(SAH):The outcome of aneurysmal SAH remains poor despite advances in the diagnosis and treatment.Although many factors related to patients,aneurysms,and institutions,as ... Target of research in subarachnoid hemorrhage(SAH):The outcome of aneurysmal SAH remains poor despite advances in the diagnosis and treatment.Although many factors related to patients,aneurysms,and institutions,as well as physiological parameters and medical complications were reported as prognostic factors, 展开更多
关键词 implications of periostin the development subarachnoid hemorrhage-induced brain injuries
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Molar-Tooth Structure from the Mesoproterozoic Wumishan Formation in Lingyuan,Yanshan Region,North China,and Geological Implications 被引量:6
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作者 KUANG Hongwei LIU Yongqing +4 位作者 PENG Nan LUO Shunshe LI Jiahua CEN Chao CHEN Mingpei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第1期85-95,共11页
Although its origin has not yet reached a consensus so far, MTS (Molar-Tooth Structure) has been documented for more than 100 years. Current study reports a discovery of MTS from the Mesoproterozoic Wumishan Formati... Although its origin has not yet reached a consensus so far, MTS (Molar-Tooth Structure) has been documented for more than 100 years. Current study reports a discovery of MTS from the Mesoproterozoic Wumishan Formation, Lingyuan, Yanshan Region, North China, and the features and geological implications of MTS are further discussed. Here, straitigraphic horizons of MTS's occurrences show that it was mainly located within the top part of the Wumishan Formation, i.e., limestone unit. Four kinds of morphology of MTS, i.e., fine fusiform, debris, ribbon, ptigmatic and nodular (irregular), were recognized and thought to be highly related to the sedimentary environments and facies. Geochemistry of MTS including oxides, trace elements and C, O and Sr isotopes indicates that the horizons of MTS-bearing is of higher Sr/Ba and Ca/Mg ratios, lower positive ~13C and highly negative 3180 values than the adjacent stratigraphic levels of rare MTS. Lithology, morphology and geochemistry of MTS in the Wumishan Formation suggest that MTS occurs mainly in shallow subtidal near the storm wave base, which is typically characterized by warm temperature, oversaturated calcium carbonate seawater and high organic productivity. Furthermore, occasional enrichment of algae bacteria here is more favorable for the calcification of calcium oozes and catalytic for MTS. C isotope composition of the Wumishan Formation and MTS of this study is well correlated with that of the Mesoproterozoic Belt Supergroup, North America and Riphean, Siberia, suggesting that MTS acts as a sedimentary record responding to global changes and is a perfect indicator in Precambrian stratigraphic correlation worldwide. 展开更多
关键词 Molar-tooth Structure Wumishan Formation MESOPROTEROZOIC implications Lingyuan Yanshan Region
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基于QL-蕴涵的Min-implication模糊关系方程的分解与求解
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作者 罗艳斌 李永明 《陕西师范大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第2期13-17,共5页
在有限论域上首先给出θFuzzy关系方程的分解,然后针对NQL 蕴涵θ探讨了θFuzzy关系方程的求解问题.基于解矩阵给出了解存在性的几个新判据.在θFuzzy关系方程A θr=b的解集ζ(A,b)非空时,证明了对每一个r∈ζ(A,b),存在ζ(A,b)中的极大... 在有限论域上首先给出θFuzzy关系方程的分解,然后针对NQL 蕴涵θ探讨了θFuzzy关系方程的求解问题.基于解矩阵给出了解存在性的几个新判据.在θFuzzy关系方程A θr=b的解集ζ(A,b)非空时,证明了对每一个r∈ζ(A,b),存在ζ(A,b)中的极大元r ,使得r ≥r. 展开更多
关键词 θ-Fuzzy关系方程 ql-蕴涵 Nql-蕴涵 极大解 平均解
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The Differences between Chinese and American Language and Culture and Its Implications for College Language Teaching and Learning
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作者 王斌花 《海外英语》 2013年第16期86-88,共3页
Chinese and American language and culture differ from each other in five ways as Hypotactic language vs. Paratactic language, Analytical thinking vs. Synthetic thinking, Direct thinking vs. Indirect thinking, Individu... Chinese and American language and culture differ from each other in five ways as Hypotactic language vs. Paratactic language, Analytical thinking vs. Synthetic thinking, Direct thinking vs. Indirect thinking, Individualism vs. Collectivism and Ethics-based vs. Legislation-based. Their implications for college language teaching and learning are worth our attention. 展开更多
关键词 LANGUAGE culture DIFFERENCES COLLEGE teaching and
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Xiba Granitic Pluton in the Qinling Orogenic Belt, Central China: Its Petrogenesis and Tectonic Implications 被引量:14
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作者 ZHANG Fan LIU Shuwen +5 位作者 CHEN Xu LI Qiugen DAI Junzhi YANG Kai WU Fenghui CHEN Youzhang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第5期1128-1142,共15页
Xiba granitic pluton is located in South Qinling tectonic domain of the Qinling orogenic belt and consists mainly of granodiorite and monzogranite with significant number of microgranular quartz dioritic enclaves. SHR... Xiba granitic pluton is located in South Qinling tectonic domain of the Qinling orogenic belt and consists mainly of granodiorite and monzogranite with significant number of microgranular quartz dioritic enclaves. SHRIMP zircon U-Pb isotopic dating reveals that the quartz dioritic enclaves formed at 214±3 Ma, which is similar to the age of their host monzogranite (218±1 Ma). The granitoids belong to high-K calc-alkaline series, and are characterized by enriched LILEs relative to HFSEs with negative Nb, Ta and Ti anomalies, and right-declined REE patterns with (La/Yb) N ratios ranging from 15.83 to 26.47 and δEu values from 0.78 to 1.22 (mean= 0.97). Most of these samples from Xiba granitic pluton exhibit εNd(t) values of 8.79 to 5.38, depleted mantle Nd model ages (T DM ) between 1.1 Ga and 1.7 Ga, and initial Sr isotopic ratios ( 87 Sr/ 86 Sr) i from 0.7061 to 0.7082, indicating a possible Meso-to Paleoproterozoic lower crust source region, with exception of samples XB01-2-1 and XB10-1 displaying higher ( 87 Sr/ 86 Sr) i values of 0.779 and 0.735, respectively, which suggests a contamination of the upper crustal materials. Quartz dioritic enclaves are interpreted as the result of rapid crystallization fractionation during the parent magmatic emplacement, as evidenced by similar age, texture, geochemical, and Sr-Nd isotopic features with their host rocks. Characteristics of the petrological and geochemical data reveal that the parent magma of Xiba granitoids was produced by a magma mingling process. The upwelling asthenosphere caused a high heat flow and the mafic magma was underplated into the bottom of the lower continent crust, which caused the partial melting of the lower continent crustal materials. This geodynamic process generated the mixing parent magma between mafic magma from depleted mantle and felsic magma derived from the lower continent crust. Integrated petrogenesis and tectonic discrimination with regional tectonic evolution of the Qinling orogen, it is suggested that the granitoids are most likely products in a post-collision tectonic setting. 展开更多
关键词 Xiba granitoids SHRIMP U-Pb ages geochemistry and Sr-Nd isotopic systematics petrogenesis and tectonic implication Qinling orogenic belt
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Chemical and Isotopic Characters of the Water and Suspended Particulate Materials in the Yellow River and Their Geological and Environmental Implications 被引量:5
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作者 DING Tiping GAO Jianfei +5 位作者 TIAN Shihong WANG Huaibai LI Ming WANG Chengyu LUO Xurong HANG Dan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期285-351,共67页
The chemical and isotopic characteristics of the water and suspended particulate materials (SPM) in the Yellow River were investigated on the samples collected from 29 hydrological monitoring stations in the mainste... The chemical and isotopic characteristics of the water and suspended particulate materials (SPM) in the Yellow River were investigated on the samples collected from 29 hydrological monitoring stations in the mainstem and several major tributaries during 2004 to 2007. The JD and δ^18O values of the Yellow River water vary in large ranges from -32%0 to -91‰ and from -3.1‰ to -12.5‰, respectively. The characters of H and O isotope variations indicate that the major sources of the Yellow River water are meteoric water and snow melting water, and water cycle in the Yellow River basin is affected strongly by evaporation process and human activity. The average SPM content (9.635 g/L) of the Yellow River is the highest among the world large rivers. Compared with the Yangtze River, the Yellow River SPM has much lower clay content and significantly higher contents of clastic silicates and carbonates. In comparison to the upper crust rocks, the Yellow River SPM contains less SiO2, CaO, K2O and Na2O, but more TFe203, Co, Ni, Cu, Zn, Pb and Cd. The abnormal high Cd contents found in some sample may be related to local industrial activity. The REE contents and distribution pattern of the Yellow River SPM are very close to the average value of the global shale. The average δ^30Sisp in the Yellow River (-0.11‰) is slightly higher than the average value (-0.22‰) of the Yangtze River SPM. The major factors controlling the δ^30Si SPM of the Yellow River are the soil supply, the isotopic composition of the soil and the climate conditions. The TDS in the Yellow River are the highest among those of world large rivers. Fair correlations are observed among Cl, Na^+, K^+, and Mg^2+ contents of the Yellow River water, indicating the effect of evaporation. The Ca^2+ and Sr^2+ concentrations show good correlation to the SO42 concentration rather than HCO3-concentration, reflecting its origin from evaporates. The NO3-contents are affected by farmland fertilization. The Cu, Zn and Cd contents in dissolved load of the Yellow River water are all higher than those of average world large rivers, reflecting the effect of human activity. The dissolved load in the Yellow River water generally shows a REE distribution pattern parallel to those for the Yangtze River and the Xijiang River. The δ^30Si values of the dissolved silicon vary in a range from 0.4%0 to 2.9%0, averaging 1.34%o. The major processes controlling the Dsi weathering process of silicate rocks, growth of and δ^30SiDiss of the Yellow River water are the phytolith in plants, evaporation, dissolution of phytolith in soil, growth of fresh water diatom, adsorption and desorption of aqueous monosilicic acid on iron oxide and human activities. The average δ^30^SiDiss value of the Yellow River is significantly lower than that of the Nile River, Yangtze River and Siberia rivers, but higher than those of other rivers, reflecting their differences in chemical weathering and biological activity. The δ^34SSO4 values of the Yellow River water range from -3.8%0 to 14.1%o, averaging 7.97%0. There is some correlation between SO4^2- content and δ^34SSO4. The factors controlling the δ^34SSO4 of the Yellow River water are the SO4 in the meteoric water, the SO4 from gypsum or anhydrite in evaporite rocks, oxidation and dissolution of sulfides in the mineral deposits, magmatic rocks and sedimentary rocks, the sulfate reduction and precipitation process and the sulfate from fertilizer. The ^87Sr/^86Sr ratios of all samples range from 0.71041 to 0.71237, averaging 0.71128. The variations in the ^87Sr/^86Sr ratio and Sr concentration of river water are primarily caused by mixing of waters of various origins with different 87Sr/S6Sr ratios and Sr contents resulting from water-rock interaction with different rock types. 展开更多
关键词 Yellow River stable isotopes water chemistry suspended particulate materials (SPM) HYDROLOGY environmental implication
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The first mitochondrial genome for the butterfly family Riodinidae(Abisara fylloides) and its systematic implications 被引量:3
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作者 Fang ZHAO Dun-Yuan HUANG +4 位作者 Xiao-Yan SUN Qing-Hui SHI Jia-Sheng HAO Lan-Lan ZHANG Qun YANG 《Zoological Research》 CAS CSCD 北大核心 2013年第5期I0001-I0011,共11页
The Riodinidae is one of the lepidopteran butterfly families. This study describes the complete mitochondrial genome of the butterfly species Abisara fylloides, the first mitochondrial genome of the Riodinidae family.... The Riodinidae is one of the lepidopteran butterfly families. This study describes the complete mitochondrial genome of the butterfly species Abisara fylloides, the first mitochondrial genome of the Riodinidae family. The results show that the entire mitochondrial genome of A. fylloides is 15301 bp in length, and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and a 423 bp A+T-rich region. The gene content, orientation and order are identical to the majority of other lepidopteran insects. Phylogenetic reconstruction was conducted using the concatenated 13 protein-coding gene (PCG) sequences of 19 available butterfly species covering all the five butterfly families (Papilionidae, Nymphalidae, Peridae, Lycaenidae and Riodinidae). Both maximum likelihood and Bayesian inference analyses highly supported the monophyly of Lycaenidae+Riodinidae, which was standing as the sister of Nymphalidae. In addition, we propose that the riodinids be categorized into the family Lycaenidae as a subfamilial taxon. 展开更多
关键词 Abisarafylloides Mitochondrial genome Riodinidae Systematic implication
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Pollen morphology of Rhododendron subgen. Tsutsusi and its systematic implications 被引量:4
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作者 Yue-Jiao ZHANG Xiao-Fen JIN +1 位作者 Bing-Yang DING Jing-Ping ZHU 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第2期123-138,共16页
Eighty-four pollen samples were obtained for 80 taxa, of which, 13 species and one variety are from sect. Brachycalyx Sweet, 58 species and two varieties from sect. Tsutsusi Sweet, and six species from subgen. Pentant... Eighty-four pollen samples were obtained for 80 taxa, of which, 13 species and one variety are from sect. Brachycalyx Sweet, 58 species and two varieties from sect. Tsutsusi Sweet, and six species from subgen. Pentanthera (G. Don) Pojarkova, respectively. Pollen morphology of all samples was observed using LM and SEM. Pollen grains are revealed to be spheroidal and tetrahedral with tricolporate apertures. Pollen sizes of subgen. Tsutsusi (Sweet) Pojarkova range from 37.67 μm to 61.06μm, and the exine sculptures are more or less compactly granulated. Pollen sizes are significantly different between sect. Brachycalyx and sect. Tsutsusi of subgen. Tsutsusi. Rhododendron tashiroi Maxim. of sect. Tsusiopsis Sleumer shows a close affinity to sect. Brachycalyx. Pollen size and exine are consistent with general morphology in differentiating species in sect. Tsutsusi. Rhododendron huadingense B. Y. Ding & Y. Y. Fang, once placed as a member of sect. Brachycalyx, should be considered as a species in subgen. Pentanthera. 展开更多
关键词 ERICACEAE Rhododendron subgen. Tsutsusi pollen morphology tetrahedral tetrads systematic implication.
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New Discovery of Molybdenite in the Dongping Gold Deposit, Hebei Province, China and its Re-Os Geochronological Implications 被引量:6
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作者 WANG Dazhao LIU Jiajun +3 位作者 ZHAI Degao ZHEN Shimin WANG Jiang YANG Xi'an 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第3期769-770,共2页
The Dongping gold deposit is located on the northern margin of the North China Craton,and is the largest alkaline pluton-related gold deposit in China(Bao et al.,2014),which is characterized by its large amounts of te... The Dongping gold deposit is located on the northern margin of the North China Craton,and is the largest alkaline pluton-related gold deposit in China(Bao et al.,2014),which is characterized by its large amounts of tellurides.The deposit is largely hosted in the Shuiquangou syenitic complex and consists of auriferous quartz veins and disseminated sulfide ores.It has been extensively studied since its discovery in the 1980s;however the geochronology and genesis of the deposit are still controversial.Nie(1998)considered that the deposit was formed in the Devonian. 展开更多
关键词 Gold DEPOSIT RE-OS GEOCHRONOLOGICAL implications
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CCA Inferred Environmental Implications of Common Ostracods on the Qinghai-Tibetan Plateau 被引量:4
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作者 SONG Gao WANG Hailei ZHENG Mianping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第2期585-597,共13页
103 surface sediment samples in 71 water bodies, such as lakes with different salinity, swamps, shallow puddles and rivers on the Qinghai-Tibetan Plateau (QTP), were collected to study the ecological distribution of... 103 surface sediment samples in 71 water bodies, such as lakes with different salinity, swamps, shallow puddles and rivers on the Qinghai-Tibetan Plateau (QTP), were collected to study the ecological distribution of living ostracods and their environmental implications. Total of 12 genus and 45 species living ostracods are identified. According to the frequencies and abundance of ostracods occurrence, Limnocythere dubiosa, Limnocytherellina kunlunensis, llyocypris bradyi, Candona candida, Eucypris rischtanica and Leucocythere dilatata are the common species on the QTP, with occurrence frequency of more than 8 and abundance of more than 570 in the 71 water bodies. Among them, L. dubiosa, occurring in 28 water bodies with 2177 shells, is the most widely distributed ostracod in this research. Canonical Correspondence Analysis (CCA) indicates high correlation between species and environmental variables, suggesting that the occurrence of species is strongly related to the changes in ecological conditions of habitats. Among eight environmental factors, salinity and pH value are the most affective variables that influence the species occurrence. L. kunlunensis is positively correlated with salinity while E. rischtanica is negatively correlated with salinity. C. candida has a positive correlation with salinity, as does I. bradyi although there is not such a strong correlation. L. dubiosa displays a positive correlation with pH value. Consequently, we discuss the environmental implications of the common living ostracods on the QTP based on the CCA as well as the distribution of ostracod species in different salinity and pH values water. L. dubiosa, L. kunlunensis and E. rischtanica are euryhaline species, among which, L. dubiosa is the most adaptable species on the QTP with large occurrence in sundry salinity water and the most widely adaptive range for pH values. L. kunlunensis prefers to saline water while E. rischtanica prefers to fresh water. Both L. kunlunensis and E. rischtanica can live in water from faintly acid to alkaline, in contrast, L. dubiosa only appears in neutral and alkaline water bodies. L bradyi only occurs in fresh water and oligohaline water with a large pH tolerance range tolerance range from weakly acidic water to alkaline water weakly acidic water to alkaline water. C. Candida lives in freshwater, with pH value above eight. The six common species reach maximum abundance in alkaline water (pH 8-10) except for llyocypris bradyi. 展开更多
关键词 Qinghai-Tibetan Plateau common living ostracods environmental implications ecological distribution Canonical Correspondence Analysis (CCA)
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Depth and region dependence of b-value for micro-aftershocks of the May 12th,2008 Wenchuan earthquake and its tectonic implications 被引量:2
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作者 Mei Feng Meijian An Lin Zhao Jizhong Zhang 《Earthquake Science》 CSCD 2009年第6期589-594,共6页
Micro-aftershocks with magnitude range of 1.5--4 around the Wenchuan earthquake epicenter, the southern part of the Longmenshan fault zone, exhibit good frequency-magnitude linear relationships, thus enabling b-value ... Micro-aftershocks with magnitude range of 1.5--4 around the Wenchuan earthquake epicenter, the southern part of the Longmenshan fault zone, exhibit good frequency-magnitude linear relationships, thus enabling b-value analysis. The average b-value for micro-aflershocks of M1.5-4 from July to December of 2008 in our local study region is about 0.88, similar to the b-value for all aftershocks ofM3.0-5.5 from May, 2008 to May, 2009 along the whole Longmenshan fault zone. The similarity between the local and regional b-values possibly indicates that the southern part of the Longmenshan fault zone has similar seismogenic environment to the whole Longmenshan fault zone. Alternatively, it may also imply that b-values derived from all events without consideration of structural variation can not discriminate local-scale tectonic information. The present study shows that the b-value for the Wenchuan earthquake micro-aftershocks varies with different regions. The b-value in southwest of the Yingxiu town is higher than that in the northeast of the Yingxiu town. The high b-value in the southwest part where the Wenchuan earthquake main shock hypocenter located indicates that the current stress around the hypocenter region is much lower than its surrounding area. The b-values are also dependent on depth. At shallow depths of 〈5 km, the b-values are very small (-0.4), possibly being related to strong wave attenuation or strong heterogeneity in shallow layers with high content of porosity and fractures. At depths of-5-11 km, where most aftershocks concentrated, the b-values become as high as -0.9-1.0. At the depth below -11 km, the b-values decrease with the depth increasing, being consistent with increasing tectonic homogeneity and increasing stress with depth. 展开更多
关键词 micro-aftershocks frequency-magnitude relationship tectonic implication Wenchuan earthquake
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Environmental Implications of Excessive Selenium: A Review 被引量:10
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作者 A. DENNIS LEMLY(United States Forest Service, Southern Research Station, Coldwater Fisheries Research Unit, Department of Fisheries and Wildlife Sciences, Virginia Tech University, Blacksburg, VA 24061-0321, USA) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1997年第4期415-435,共21页
Selenium is a naturally occurring trace element that is nutritionally required in smallamounts but it can become toxic at concentrations only twice those required. The narrow mar-gin between beneficial and harmful lev... Selenium is a naturally occurring trace element that is nutritionally required in smallamounts but it can become toxic at concentrations only twice those required. The narrow mar-gin between beneficial and harmful levels has important implications for human activities thatincrease the amount of selenium in the environment. Two of these activities, disposal of fbssilfuel wastes and agricultural irrigation of arid, seleniferous soils, have poisoned fish andwildlife, and threatened public health at several locations in the United States. Research stud-ies of these episodes have generated a data base that clearly illustrates the environmental hazardof excessive selenium. It is strongly bioaccumulated by aquatic organisms and even slight in-creases in waterborne concentrations can quickly result in toxic effects such as deformed em-bryos and reproductive failure in wildlife. The selenium data base has been very beneficial indeveloping hazard assessment procedures and establishing environmentally sound water qualitycriteria. The two faces of selenium, required nutrient and Potent toxin, make it a particularlyimportant trace element in the health of both animals and man. Because of this paradox, envi-ronmental selenium in relation to agriculture, fisheries, and wildlife wiIl continue to raise im-POrtant land and water management issues for decades to come. If these issues are dealt withusing prudence and the available environmental selenium data base, adverse irnpacts to naturalresources andspublic health can be avoided 展开更多
关键词 In A Review Environmental implications of Excessive Selenium
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