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Characteristics and Significance of Carbon and Oxygen Isotopic Compositions of the PTB Boundary in Haidai Section,Xuanwei Area of China
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作者 Chenming Liu Demin Yang Zhengqin Na 《Journal of Environmental & Earth Sciences》 2025年第5期203-214,共12页
The End-Permian mass extinction(EPME),Earth’s most severe biocrisis,occurred proximal to the Permian-Triassic Boundary(PTB),with marine ecosystems experiencing catastrophic collapse.This study employs stable carbon(... The End-Permian mass extinction(EPME),Earth’s most severe biocrisis,occurred proximal to the Permian-Triassic Boundary(PTB),with marine ecosystems experiencing catastrophic collapse.This study employs stable carbon(δ^(13)C)and oxygen isotopes from marine carbonates in the Haidai Section(Xuanwei,northeastern Yunnan)to decipher paleoenvironmental drivers.The well-preserved stratigraphic sequence encompasses the Upper Permian(Yangxin and Xuanwei Formations)transitioning into the Lower Triassic(Feixianguan and Jialingjiang Formations),providing a continuous marine sedimentary archive.A marked negativeδ^(13)C excursion(-9.66‰V-PDB)occurs at the PTB,initiating from+0.82‰with subsequent gradual recovery.This geochemical signature correlates with:90%reduction in primary productivity Biodiversity collapse exhibiting cluster extinction patterns Prolonged suppression of ecological recovery Concurrently,reconstructed seawater temperatures reveal extreme thermal fluctuations,surging from 23℃to 32℃at the PTB before precipitously declining to 16℃.These perturbations demonstrate coupled biogeochemical dynamics wherein:•Carbon cycle destabilization disrupted nutrient fluxes.•Temperature oscillations exceeded marine taxa thermal tolerances.•Synergistic environmental stresses amplified extinction selectivity.Theδ^(13)C-temperature covariance(r^(2)=0.085)establishes mechanistic linkages between physicochemical perturbations and biotic responses.Our findings demonstrate that the EPME was driven by positive feedback loops in which:Volcanic CO₂emissions triggered carbonate saturation decline Thermal stratification exacerbated anoxia Biogeochemical cycling perturbations suppressed primary producers This integrated geochemical record from the Haidai Section provides critical insights into environment-organism coevolution during Phanerozoic Earth’s most profound mass extinction. 展开更多
关键词 Carbon and Oxygen Isotope Northeastern Yunnan xuanwei PTB ELIP Mass Extinction
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Changes of Intramuscular Fat Composition,Lipid Oxidation and Lipase Activity in Biceps femoris and Semimembranosus of Xuanwei Ham During Controlled Salting Stages 被引量:5
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作者 WANG Zhen-yu GAO Xiao-guang +2 位作者 ZHANG Ji-hong ZHANG De-quan MA Chang-wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第11期1993-2001,共9页
Fatty acid composition of neutral lipids (NLs), phospholipids (PLs) and free fatty acids (FFAs) from intramuscular fat (IMF), lipid oxidation and lipase activity in muscle Semimembranosus (SM) and msucle Bic... Fatty acid composition of neutral lipids (NLs), phospholipids (PLs) and free fatty acids (FFAs) from intramuscular fat (IMF), lipid oxidation and lipase activity in muscle Semimembranosus (SM) and msucle Biceps femoris (BF) of dry-cured Xuanwei ham during the 90-d salting stages were analysed. The salt content increased from 0.34 to 3.52%in BF and from 0.10 to 5.42%in SM during the 90 d salting stage, respectively. PLs of IMF in both BF and SM decreased 54.70%(P〈0.001) and 34.64%(P〈0.05), furthermore, the saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) of PLs in both muscles were hydrolysed almost isochronously. FFAs were increased from 0.46 g 100 g-1 lipids to 2.92 g 100 g-1 lipids in BF at the end of salting, which was lower than SM (from 1.29 g 100 g-1 lipids to 9.70 g 100 g-1 lipids). The activities of acid lipase, neutral lipase and acid phospholipase all remained active in the 90 d. The thiobarbituric acid reactive substances (TBARS) was slowly increased to 1.34 mg kg-1 muscle in BF and to 2.44 mg kg-1 muscle in SM during the salting stage. In conclusion, the controlled salting process prompted the hydrolysis of PLs of IMF notably and increased the lipid oxidation of muscles within some limits. 展开更多
关键词 xuanwei ham intramuscular fat lipid oxidation fatty acid composition SALTING
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Provenance of the Late Permian Xuanwei Formation in the Upper Yangtze Block: Constraints from the Sedimentary Record and Tectonic Implications 被引量:5
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作者 ZHANG Yingli JIA Xiaotong WANG Zongqi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第6期1673-1686,共14页
Xuanwei Formation is composed of mudstone,siltstone,and sandstone,with local conglomerate.However,its provenance and tectonic setting have been scarcely studied.In this paper,we use sedimentology,electron probe microa... Xuanwei Formation is composed of mudstone,siltstone,and sandstone,with local conglomerate.However,its provenance and tectonic setting have been scarcely studied.In this paper,we use sedimentology,electron probe microanalysis(EPMA),and detrital zircon dating to investigate its source area and depositional tectonic setting.The facies assemblages indicate that it formed in alluvial fan and fluvial river sedimentary environments.The strata thicknesses and facies distribution indicate that the sediment supply was from the west.The results of EPMA show that chromian spinels within the sediments are characterized by high Cr#and varying Mg#.Discrimination plots suggest that these spinels were sourced from large igneous province(LIP)magmatic rocks.The laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS)U–Pb chronology of detrital zircons suggests that the sediments were derived from intermediate–acid igneous rocks dating back to 251–260?Ma.We could,therefore,conclude that the provenance of the Xuanwei Formation is from Emeishan basalt and synchronous felsic igneous rocks,which is consistent with the composition of the detrital framework.The detrital zircon dates also suggest that felsic magmatism occurred during the Late Permian,not after the eruption of the Emeishan basalt.Based on the sedimentary successions and provenance analysis,the tectonic setting for Xuanwei Formation deposition was a volcanic rifted margin. 展开更多
关键词 xuanwei Formation provenance analysis chromian spinel detrital zircon geochronology volcanic rifted margin
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Risk Factors for Lung Cancer in Non-smokers in Xuanwei County of China 被引量:13
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作者 LAN QING, CHEN WEI, CHEN HONG, AND HE XING-ZHOUInstitute of Environmental Health and Engineering, Chinese Academy of Preventive Medicine 29 Nan Wei Road, Beijing 100050, China 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1993年第2期112-118,共7页
Tobacco smoking and some types of occupational exposures have consistently been considered as important etiologic factors of lung cancer in industrial countries. At the First World Conference of Lung Cancer (Wyndwer, ... Tobacco smoking and some types of occupational exposures have consistently been considered as important etiologic factors of lung cancer in industrial countries. At the First World Conference of Lung Cancer (Wyndwer, 1983), it was stressed that more attention should be paid to finding out the causes of lung cancer in non-smokers.In Xuanwei County, Yunnan Province, annual lung cancer death rate was 27.7 per 100,000 in males, among China's highest, and 25.3 per 100,000 in females, the China's highest. The female's lung cancer death rate in Xuanwei County was even much higher than that of the same period in USA white women (ECACM, 1979; Mulvihill, 1976). Marked district variation in cancer mortality exists within Xuanwei County. The county can be divided into high-, medium- and low-mortality areas. Over 90% of the population arc farmers. The local residents traditionally burned three major kinds of fuels: 'smoky' coal, 'smokeless' coal and 'wood', for heating and cooking. The three lung cancer high mortality areas, including 'Chengguan', 'Rongcheng' and 'Laibin' communes, mainly burned the 'smoky' coal from Laibin smoky-coal mine. The fuel was burned in a shallow, unventilated fire pit in the floor of the dwelling. Fuel burning in shallow unventilated pits has resulted in high indoor air pollution levels. The concentrations of airborne particles (pm 10) inside houses during smoky coal and wood combustion were very high. Indoor concentration of suspended particulates and dichloromethane extractable organics were 24.4mg/m3 and 17.6mg/m3 in burning of 'smoky' coal; 22.3mg/m3, 12.3mg/m3 for burning wood; and 1.8mg/m3, O.Smg/m-1 for burning of smokeless coals. Levels of individual polycyclic aromatic hydrocarbons, including benzo(a)pyrene, were generally highest during burning of smoky coal, intermediate in burning wood, and least in smokeless coal. Women did most household chores, which include starting fire and cooking. Less than 0.2% of females smoked tobacco. The population-based case-control study presented here is to evaluate the influence of factors on the occurrence of lung cancer in non-smoking women in Xuanwei County and to supplement the etiologic factors of lung cancer in Xuanwei County. 展开更多
关键词 LUNG Risk Factors for Lung Cancer in Non-smokers in xuanwei County of China
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The expression of PAH-DNA adducts in lung tissues of Xuanwei female lung cancer patients 被引量:3
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作者 Kaiyun Yang Yunchao Huang Guangqiang Zhao Yujie Lei Kun Wang 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第9期497-501,共5页
Objective:The coal-fired pollution in Xuanwei area has been considered to be local main reason for high incidence of female lung cancers.The aim of the study was to investigate the expression of PAH-DNA adducts in lun... Objective:The coal-fired pollution in Xuanwei area has been considered to be local main reason for high incidence of female lung cancers.The aim of the study was to investigate the expression of PAH-DNA adducts in lung tissues of Xuanwei female lung cancer patients, and to explore the relationship between the large number of coal-fired pollution PAHs materials and the high incidence of Xuanwei female lung cancers.Methods:We totally collected each 20 cases of Xuanwei female lung cancer patients, Xuanwei male lung cancer patients, non-Xuanwei female lung cancer patients and collected each 10 cases of Xuanwei, non-Xuanwei female patients with benign lung lesions.The cancer tissues, adjacent cancer tissues and normal lung tissues were collected in lung cancer patients and only the normal tissues were collected in benign lung lesion patients.There were total 80 cases and 200 tissues.Using immunofluorescence, we detected the expression of PAH-DNA adducts in each group.Image pro-plus 6.0 software was used to analyze the images and did part quantified analysis.SPSS 13.0 statistical software was used to analyze the data.Results:The positive expressions of PAH-DNA adducts in lung cancer tissues, adjacent cancer tissues and normal lung tissues of Xuanwei female lung cancer patients were 90%, 80% and 65%, respectively.They were higher than the positive expressions of PAH-DNA adducts in Xuanwei male lung cancer patients (35%, 30% and 30%) and non-Xuanwei female lung cancer patients (20%, 15% and 10%; P<0.01).The expression of PAH-DNA adducts in lung tissues of Xuanwei female benign lung lesion patients (70%) was higher than that in non-Xuanwei female benign lung lesion patients (10%).With the direction changing from cancer tissues, adjacent cancer tissues to normal lung tissues, the expression of PAH-DNA adducts was decreased but had no statistical difference (P>0.05).Conclusion:The expression of PAH-DNA adducts in lung tissues of Xuanwei females was higher than that in Xuanwei males and non-Xuanwei females. 展开更多
关键词 polycylic aromatic hydrocarbons (PAHs) adduct IMMUNOFLUORESCENCE xuanwei female lung cancers
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The expression of Survivin in lung adenocarcinoma:a comparative study in Xuanwei and Kunming
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作者 Weiwei Wang Gaofeng Li +4 位作者 Zhipeng Hong Shaojia Wang Ruibing Cheng Shoujun Deng Jupeng Zhang 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第11期625-627,共3页
Objective: The aim of our study was to investigate the expression of Survivin in lung adenocarcinoma of Xuanwei and Kunming patients. Methods: Twenty-five specimens of Xuanwei patients and 28 specimens of Kunming pati... Objective: The aim of our study was to investigate the expression of Survivin in lung adenocarcinoma of Xuanwei and Kunming patients. Methods: Twenty-five specimens of Xuanwei patients and 28 specimens of Kunming patients were observed and analyzed. The Survivin expression was detected by immunohistochemistry. The results were quantitatively analyzed by image analysis system. Results: There were significant differences in Survivin expression (P < 0.01) between Xuanwei patients and Kunming patients. Conclusion: Survivin expression in lung adenocarcinoma of Xuanwei patients was significantly higher than that of Kunming patients. The pathogenesis of lung adenocarcinoma might be different between Xuanwei patients and Kunming patients. High Survivin expression might be one of the reasons to explain high incidence of lung cancer in Xuanwei. 展开更多
关键词 lung adenocarcinoma SURVIVIN xuanwei Kunming
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Xuanwei Power Plant 5th Phase Project was completely built up
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《Electricity》 2001年第4期51-51,共1页
关键词 PROJECT xuanwei Power Plant 5th Phase Project was completely built up
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Geochemical characteristics of the Xuanwei Formation in West Guizhou:Significance of sedimentary environment and mineralization 被引量:11
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作者 ZHANG Zhengwei YANG Xiaoyong +1 位作者 LI Shuang ZHANG Zhongshan 《Chinese Journal Of Geochemistry》 EI CAS 2010年第4期355-364,共10页
The Upper Permian Xuanwei Formation widely occurs in western Guizhou,unconformably overlying the Emeishan basalts,and mainly consists of black shales.It is~170 m thick at Cuyudong Village,Weining County,West Guizhou,... The Upper Permian Xuanwei Formation widely occurs in western Guizhou,unconformably overlying the Emeishan basalts,and mainly consists of black shales.It is~170 m thick at Cuyudong Village,Weining County,West Guizhou,China,where the samples of black shale and sandy shale were collected and analyzed.The shales mainly contain SiO2,18.9%?44.1%,Al2O3,14.8%?52.8%,Fe2O3,1.0%?41.2%,LOI,3.2%?21.1%,TiO2,1.0%-6.7%,and MgO,0.2%?2.5%.The contents of all other major elements are lower than 1.0%.It is shown that the black shales have higher contents of Fe2O3 and LOI than normal shales.The siderites occurred in the black shales with higher contents of Fe2O3,which may be attributed to hydrothermal activities on seafloor.All analyzed shale samples have extremely high Ga,47.8×10-6-109.9×10-6(70.5×10-6 on average),higher than the industrial mining standard of Ga Resource Industry Standard.The total contents of rare-earth elements(REE) of 9 black shale samples vary from 213×10-6 to 1460×10-6,suggesting that these black shales are enriched in REE.The shale-normalized REE patterns display both positive and negative Ce anomalies(Ce/Ce* from 0.5 to 1.7),revealing that the Xuanwei shales were precipitated under oxic and anoxic conditions.The Rb-Sr chronological diagram of 6 shale samples in the Xuanwei Formation shows an age of 255±12 Ma.Strontium isotopic ratios(87Sr/86Sr)t0 range from 0.70635 to 0.70711,suggesting that these Xuanwei black shales might be derived from chemical weathering of the Emeishan basalts. 展开更多
关键词 贵州西部 地球化学特征 宣威组 成矿作用 沉积环境 峨眉山玄武岩 黑色页岩 稀土元素
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The characteristics of minerals in civil coal and its combustion products in Xuanwei County, Yunnan, China
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作者 Mingyuan WU Yuegang TANG Xiaole SHI 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期50-50,共1页
关键词 肺癌 燃烧产物 原煤 颗粒
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Temporal trend of mortality from major cancers in Xuanwei, China
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作者 Hualiang Lin Bofu Ning +3 位作者 Jihua Li Guangqiang Zhao Yunchao Huang Linwei Tian 《Frontiers of Medicine》 SCIE CAS CSCD 2015年第4期487-495,共9页
Although a number of studies have examined the etiology of lung cancer in Xuanwei County, China, other types of cancer in this county have not been reported systematically. This study aimed to investigate the temporal... Although a number of studies have examined the etiology of lung cancer in Xuanwei County, China, other types of cancer in this county have not been reported systematically. This study aimed to investigate the temporal trend of eight major cancers in Xuanwei County using data from three mortality surveys (1973-1975, 1990-1992, and 2004-2005). The Chinese population in 1990 was used as a standard population to calculate age- standardized mortality rates. Cancers of lung, liver, breast, brain, esophagus, leukemia, rectum, and stomach were identified as the leading cancers in this county in terms of mortality rate. During the three time periods, lung cancer remained as the most common type of cancer. The mortality rates for all other types of cancer were lower than those of the national average, but an increasing trend was observed for all the cancers, particularly from 1990-1992 to 2004-2005. The temporal trend could be party explained by changes in risk factors, but it also may be due to the improvement in cancer diagnosis and screening. Further epidemiological studies are warranted to systematically examine the underlying reasons for the temporal trend of the major cancers in Xuanwei County. 展开更多
关键词 CANCER MORTALITY xuanwei temporal trend
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Xuanwei ham derived peptides exert the anti-inflammatory effect in the dextran sulfate sodium-induced C57BL/6 mice model
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作者 Lujuan Xing Lijuan Fu +2 位作者 Yuejing Hao Yujia Miao Wangang Zhang 《Food Bioscience》 SCIE 2022年第4期530-540,共11页
The dry-cured hams are produced by a long-term fermentation along with amounts of bioactive peptides are generated.Previously,the bioactive peptides in ham have been reported with antioxidant,antihypertensive,and anti... The dry-cured hams are produced by a long-term fermentation along with amounts of bioactive peptides are generated.Previously,the bioactive peptides in ham have been reported with antioxidant,antihypertensive,and anti-inflammatory effects.Currently,the Xuanwei ham peptides(XP)were evaluated in dextran sodium sulfate(DSS)-induced C57BL/6 mice trial to investigate their effects on inflammatory bowel disease(IBD)symptoms.As result,the IBD symptoms of colon shorten,tissue damage,and colonic tissue inflammation were all ameliorated in the supplement of XP.The inflammatory cytokines(TNF-α,IL-6,MCP-1)in the colon were also suppressed by XP intervention compared to DSS-induced treatment.In addition,the intake of XP was checked to modulate the gut microbiota structure,including increasing the relative abundances of Akkermansia,Parasutterella,Dorea,and decreasing the relative abundances of Saccharibacteria,Olsenella,Peptococcus.Generally,the results implied that XP could attenuate the DSS-induced colitis symptoms by regulating the secretion of inflammatory cytokines as well as regulating the gut microbiota. 展开更多
关键词 xuanwei ham peptides IBD COLITIS Inflammatory cytokines Gut microbiota
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Expression of PANDA, LincRNA-p21, PUMA in lung tissues of lung cancer patients in the Xuanwei and non-Xuanwei areas of Yunnan Province
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作者 Kai-Yun Yang Zhi-Qiang Shen +6 位作者 Yue-Feng He Kushal Rizal Hui Tan An-Ning Chen Yun-Chao Huang Guang-Qiang Zhao Yu-Jie Lei 《Journal of Cancer Metastasis and Treatment》 CAS 2017年第1期65-70,共6页
Aim:To study the expression of PANDA,LincRNA-p21,and PUMA in lung tissue of patients with lung cancer from Xuanwei of Yunnan Province.Methods:Forty-five cases of lung cancer patients from Xuanwei and 42 lung cancer ca... Aim:To study the expression of PANDA,LincRNA-p21,and PUMA in lung tissue of patients with lung cancer from Xuanwei of Yunnan Province.Methods:Forty-five cases of lung cancer patients from Xuanwei and 42 lung cancer cases from non-Xuanwei were enrolled.Extraction of RNA was done using the Trizol kit.Real-time fluorescence quantitative PCR assay was done to obtain the relative expression.Results:Expressions of PANDA,LincRNA-p21,and PUMA in male and female patients or in squamous cell carcinoma and adenocarcinoma were not significantly different(P>0.05).However,expression of LincRNA-p21 in Xuanwei patients was higher than non-Xuanwei patients(P<0.05).Expression of PUMA in tumor tissue was lower than that in normal lung tissue(P<0.05),and i n Xuanwei patients was lower than non-Xuanwei patients(P<0.05).In patients from non-Xuanwei regions,expression of LincRNA-p21 in patients with smoking index>400 was higher than in those<400 and non-smokers.Conclusion:Expressions of PANDA,LincRNA-p21,and PUMA in lung tissues have no gender differences or tissue specificity.High expression of LincRNA-p21 in Xuanwei patients may have relationship with cell damage caused by coal burning pollution in Xuanwei. 展开更多
关键词 Lung cancer PANDA LincRNA-p21 PUMA xuanwei area
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川南高县地区浅层煤体积压裂技术优化思路及应用
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作者 李炘潼 《能源与节能》 2026年第1期70-73,共4页
川南高县地区浅层煤以多薄煤层发育为特征,优质储层为上二叠统宣威组C_(6)、C_(7)、C_(8)煤层。经区块前期试验评价,目的储层割理发育,物性参数表现为低孔低渗特征,且含气性高、具异常高压属性,顶底板抗压强度与煤层差异显著,具备良好... 川南高县地区浅层煤以多薄煤层发育为特征,优质储层为上二叠统宣威组C_(6)、C_(7)、C_(8)煤层。经区块前期试验评价,目的储层割理发育,物性参数表现为低孔低渗特征,且含气性高、具异常高压属性,顶底板抗压强度与煤层差异显著,具备良好的煤层气区域封盖条件和压裂条件。结合邻近筠连区块压裂工艺、高县区块前期试验井压裂参数,从射孔参数、施工排量、支撑剂、压裂液、暂堵转向5个方向进行优化,并组织现场应用,最终微地震监测SRV(Stimulated Reservoir Volume,储层改造体积)为4.83×10^(5) m^(3),单井平均日产气量有所提升,储层改造效果明显,为高效、安全、经济开发目标区块浅层煤层气提供了有力的技术支撑。 展开更多
关键词 高县地区 浅层煤 宣威组 体积压裂技术 优化思路
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贵州清水江“凯-麻”中心城区防洪工程布局研究
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作者 张侨 黄晓彤 +1 位作者 郑晨晨 张孟丹 《黑龙江水利科技》 2026年第1期116-119,123,共5页
清水江“凯-麻”中心城区河段多次遭遇洪水灾害,对生命财产和生态环境造成严重威胁。为提升区域防洪能力,本文基于全流域视角,采用洪水频率分析、防洪库容测算、堤防布置优化和投资效益对比等方法,系统研究了防洪工程布局方案。结果表明... 清水江“凯-麻”中心城区河段多次遭遇洪水灾害,对生命财产和生态环境造成严重威胁。为提升区域防洪能力,本文基于全流域视角,采用洪水频率分析、防洪库容测算、堤防布置优化和投资效益对比等方法,系统研究了防洪工程布局方案。结果表明,推荐的“高堤小库”方案在保证防洪标准(下司30 a一遇、凯里50 a一遇)的同时,投资总额相对较低(14.70亿元),且对古镇景观影响较小、移民量可控。研究成果可为宣威水库及防洪堤规模的科学确定提供决策支撑,并对类似山区河流城市的防洪规划具有参考价值。 展开更多
关键词 宣威水库 凯-麻中心城区 防洪布局 防洪库容
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宣威地区土壤重金属潜在污染风险评价及影响因素解析 被引量:3
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作者 韩伟 宋云涛 +6 位作者 郭志娟 曾道明 贺灵 成晓梦 孙彬彬 张富贵 张利 《中国环境科学》 北大核心 2025年第5期2643-2653,共11页
我国西南生态功能保护区内存在土壤重金属高含量区,为探究其潜在污染风险及影响因素,选择云南省宣威地区土壤为研究对象,结合地理、地质、人类活动等相关资料,对区内表层组合土壤样品1487份、深层组合土壤样品374份中的8种重金属元素含... 我国西南生态功能保护区内存在土壤重金属高含量区,为探究其潜在污染风险及影响因素,选择云南省宣威地区土壤为研究对象,结合地理、地质、人类活动等相关资料,对区内表层组合土壤样品1487份、深层组合土壤样品374份中的8种重金属元素含量特征进行了分析,分别利用地累积指数法和潜在生态危害指数法评价了表层组合土壤的潜在污染风险,采用主成分分析法和地理探测器对其影响因素进行了解析.结果显示,相对于中国土壤A层、C层背景值研究区表、深层土壤中重金属均显示富集;相对于云南省A层、C层土壤背景值大部分重金属亦显示富集;Cd、Hg、Pb存在较高的潜在污染风险,Cu、Cr、Ni、Zn、As则潜在污染风险较低;地质背景、黏土矿物、有机质、矿业活动、地形地貌是土壤中重金属元素的主要影响因素,多影响因素的协同作用可能会使重金属富集加剧,pH值、CaO、Light(灯光指数)、WIG对重金属富集的影响则较小. 展开更多
关键词 宣威地区 土壤重金属 潜在生态危害指数 地累积指数 主成分分析
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华南西部晚二叠世玄武质源-汇沉积体系的侵蚀演变与成矿效应
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作者 杨江海 王彪 +5 位作者 黄庆 王茂德 陈波 周寅生 邓旭升 覃永军 《矿物岩石地球化学通报》 北大核心 2025年第5期1008-1022,I0003,共16页
源-汇沉积系统(S2S)通过沉积路径将侵蚀地貌区与沉积地貌区进行有机联系,通过沉积物从源到汇的传输和存储将侵蚀地貌演化转变为地质历史记录。本文在简述源-汇沉积体系地貌侵蚀研究的基础上,全面总结了华南西部晚二叠世的源-汇沉积体系... 源-汇沉积系统(S2S)通过沉积路径将侵蚀地貌区与沉积地貌区进行有机联系,通过沉积物从源到汇的传输和存储将侵蚀地貌演化转变为地质历史记录。本文在简述源-汇沉积体系地貌侵蚀研究的基础上,全面总结了华南西部晚二叠世的源-汇沉积体系研究进展。该源-汇沉积体系的沉积物来源于峨眉山大火成岩省的风化侵蚀,向东南输送并堆积于右江盆地的不同沉积环境,保存了完整的从陆相、滨-浅海相到深水盆地相的沉积序列。利用陆相宣威组的沉积学和沉积物源分析,完善了该源-汇沉积体系,进一步明确了吴家坪中期的华南西部侵蚀地貌演变及其驱动机制;通过宣威组下段含矿岩系的详细沉积学分析,建立了冲积扇-湿地沉积相组合模式,厘定了吴家坪早期的风化-沉积成矿效应。 展开更多
关键词 源-汇沉积体系 侵蚀地貌 宣威组 晚二叠世 沉积矿床
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川滇黔地区晚二叠世碎屑-黏土岩系中稀土-钪多金属富集层研究进展、存在问题及展望
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作者 黄小文 王琪 +4 位作者 周美夫 杨志爽 孟郁苗 孔志岗 漆亮 《矿物学报》 北大核心 2025年第4期656-671,共16页
稀土-钪作为战略性关键金属,其成矿作用研究广受关注。在川滇黔地区晚二叠世碎屑-黏土岩系(如宣威组)中广泛发育稀土-钪多金属富集层,显示出较大的稀土及钪资源潜力。前人在稀土和钪的赋存状态、物质来源、迁移沉淀机制以及成矿模式等... 稀土-钪作为战略性关键金属,其成矿作用研究广受关注。在川滇黔地区晚二叠世碎屑-黏土岩系(如宣威组)中广泛发育稀土-钪多金属富集层,显示出较大的稀土及钪资源潜力。前人在稀土和钪的赋存状态、物质来源、迁移沉淀机制以及成矿模式等方面均取得了重要进展,但是由于该类型金属矿产具有“稀、伴、细”等特点,传统的结构和成分观测技术受到制约,无论是稀土和钪的赋存状态还是“源-运-聚”过程均存在较大争议,严重制约了宣威组稀土-钪多金属富集层的开发利用和找矿勘查。本文总结了前人已取得的重要成果,采用统计学方法对已报道的数据进行了进一步梳理,初步明确了稀土-钪的基本富集规律以及它们在岩浆-风化-沉积过程中的地球化学行为,并基于现有研究中存在的一些不足,提出了下一步的研究方向。 展开更多
关键词 稀土-钪 赋存状态 富集机制 宣威组
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宣威火腿发酵成熟过程中不同部位肌肉的品质变化及风味形成
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作者 梁伟 张璐 +2 位作者 汪雪娇 殷小钰 曹建新 《食品与发酵工业》 北大核心 2025年第23期267-276,I0011-I0016,共16页
脂质和蛋白质氧化对火腿品质和风味的形成具有重要的影响。该研究以宣威火腿不同部位的肌肉为对象,研究半膜肌和股二头肌发酵成熟过程中蛋白质与脂质氧化、基本理化指标以及挥发性化合物的变化。结果表明,随着发酵时间的延长,半膜肌与... 脂质和蛋白质氧化对火腿品质和风味的形成具有重要的影响。该研究以宣威火腿不同部位的肌肉为对象,研究半膜肌和股二头肌发酵成熟过程中蛋白质与脂质氧化、基本理化指标以及挥发性化合物的变化。结果表明,随着发酵时间的延长,半膜肌与股二头肌水分含量、过氧化值、亮度值、水分活度和活性巯基含量均呈显著下降趋势(P<0.05),硬度、咀嚼性、红度值、硫代巴比妥酸值、表面疏水性和羰基含量随着发酵时间的延长均显著增加(P<0.05),不同部位肌肉之间均具有显著性差异(P<0.05);对于整体气味感知,利用电子鼻可以分别区分不同发酵时间以及同一发酵时间的半膜肌和股二头肌之间的气味。醇类、醛类和酯类是宣威火腿主要的风味化合物,股二头肌的风味化合物种类多于半膜肌(P<0.05)。通过偏最小二乘法分析,19种挥发性化合物与宣威火腿发酵成熟过程中的蛋白质和脂质氧化存在显著相关性。 展开更多
关键词 宣威火腿 肌肉部位 蛋白质氧化 脂质氧化 电子鼻 挥发性化合物
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四川峨眉山地区晚二叠世—早三叠世古气候演变过程
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作者 周斌 胡作维 +1 位作者 李云 任柳洁 《地球科学与环境学报》 北大核心 2025年第2期230-247,共18页
在二叠纪—三叠纪之交,全球经历了重大的气候变化和生物更替,相关地质事件一直是地学领域的研究热点。四川峨眉山地区发育晚二叠世—早三叠世陆相沉积,其对二叠纪—三叠纪之交的古气候研究具有重要意义。通过野外剖面观察、薄片分析、... 在二叠纪—三叠纪之交,全球经历了重大的气候变化和生物更替,相关地质事件一直是地学领域的研究热点。四川峨眉山地区发育晚二叠世—早三叠世陆相沉积,其对二叠纪—三叠纪之交的古气候研究具有重要意义。通过野外剖面观察、薄片分析、主微量元素地球化学分析,认为晚二叠世—早三叠世以曲流河环境为主,在早三叠世河流规模变大。其中,晚二叠世(宣威组沉积时期)环境较为稳定,岩石中富含炭屑,长石体积分数低且具有较高的古风化特征相关指数,早三叠世(东川组沉积时期)总体化学风化强度较低,长石体积分数升高并伴随大量同生泥质角砾出现,反映该地区气候在二叠纪—三叠纪之交由潮湿炎热的陆相环境转变为干旱高温的过渡相环境,同时使水体盐度升高。气候的剧变可能由火山活动和不同规模的野火事件引起,同时受到早三叠世巨型季风的影响。 展开更多
关键词 古气候 晚二叠世—早三叠世 宣威组 东川组 沉积环境 元素地球化学 四川盆地
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峨眉山地幔柱上涌事件的成矿效应——研究进展与展望 被引量:1
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作者 刘治成 《地质论评》 北大核心 2025年第4期1325-1346,共22页
峨眉山地幔柱一直以来都是国内外学者的研究热点,但对峨眉山地幔柱的研究多集中于基础理论研究,与成矿效应有关的研究相对较少。为了补充和完善峨眉山地幔柱成矿系统,笔者等对近年来的研究成果进行了系统归纳,总结了各种矿床类型的特征... 峨眉山地幔柱一直以来都是国内外学者的研究热点,但对峨眉山地幔柱的研究多集中于基础理论研究,与成矿效应有关的研究相对较少。为了补充和完善峨眉山地幔柱成矿系统,笔者等对近年来的研究成果进行了系统归纳,总结了各种矿床类型的特征及成因。在此基础上,梳理了矿床时空分布规律和演化历史,并提出了未来峨眉山地幔柱成矿系统的研究重点和找矿方向。首先,按照成矿作用与峨眉山地幔柱上涌的时间关系,划分为两种类型:①伴随着峨眉山地幔柱上涌,在上涌过程中会发生岩浆成矿作用和热液成矿作用,最终分别形成了岩浆矿床和热液矿床,这些矿床称之为与峨眉山地幔柱直接相关的矿床类型;②在峨眉山地幔柱结束上涌后,并且间断一定时间之后,峨眉山地幔柱上涌事件为矿床提供成矿物质来源、运矿通道和成矿空间,这些矿床称之为与峨眉山地幔柱间接相关的矿床类型。其次,分析了矿床时空分布规律和演化历史;结果显示与峨眉山地幔柱直接相关的矿床的成矿时代集中在260 Ma附近;在空间上,主要分布在南北向断裂带上,与岩浆通道密切相关,且在岩浆通道垂向上具有成矿分带性;其演化历史与峨眉山地幔柱上涌过程中在岩浆通道中的不同空间位置发生的岩浆作用和热液作用密切相关。与峨眉山地幔柱间接相关的矿床的成矿时代较为分散;在空间上,主要分布在峨眉山大火成岩省中带和外带,并具有分散性、层位性特点;其演化历史与峨眉山大火成岩省形成之后提供的物源层或成矿元素初始富集层、古深大断裂和储矿空间息息相关,并且不同的矿床类型具有不同的演化特点。峨眉山地幔柱成矿系统孕育了丰富的稀有、稀土、稀散和稀贵金属等绝大部分关键矿产,矿床类型多样,成矿潜力大。建议加强峨眉山地幔柱成矿系统在成矿理论、成矿机制、成矿预测、综合回收利用技术和成矿元素多元化找矿等方面的研究,可大大提升中国关键矿产的保障能力。 展开更多
关键词 峨眉地幔柱 峨眉山大火成岩省 成矿系统 宣威组 成矿作用
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