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白肋烟新品种云白2号的选育及其特征特性 被引量:13
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作者 柴家荣 《中国烟草科学》 CSCD 北大核心 2011年第2期1-5,共5页
云白2号是以Kentucky14为母本、Burley64为父本杂交选育的白肋烟新品种。该品种遗传性状稳定,田间生长整齐,长势较强。打顶后平均株高152.7 cm,茎围12.2 cm,节距5.0 cm。有效叶25片,比对照多1~3片。平均腰叶长73.5 cm,宽34.1 cm,顶叶长... 云白2号是以Kentucky14为母本、Burley64为父本杂交选育的白肋烟新品种。该品种遗传性状稳定,田间生长整齐,长势较强。打顶后平均株高152.7 cm,茎围12.2 cm,节距5.0 cm。有效叶25片,比对照多1~3片。平均腰叶长73.5 cm,宽34.1 cm,顶叶长55.6 cm,宽26.0 cm。叶形长椭圆,叶尖渐尖,叶耳中等,茎叶角度适中。叶色黄绿,叶面较平,主脉粗细中等,花序稍密,花冠红色。苗期55~60 d,大田生育期90 d左右,成熟集中。较耐肥,适应性较强。抗黑胫病,中抗TMV,感赤星病。示范区平均产量及上中等烟比例与对照相当,产值增加4.22%~10.66%,均价提高0.38~0.46元/kg,主要经济性状良好。外观质量较好,化学成分适宜,比例较协调,风格特征较明显,香味较丰富,透发性好,刺激性略大,杂气略重,吸食品质整体优于对照。 展开更多
关键词 白肋烟 品种 选育 特征特性 云白2号
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白肋烟新品种云白3号的选育及其特征特性 被引量:2
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作者 柴家荣 管仕军 +3 位作者 字萍 张晨东 轩书章 王涵 《中国烟草科学》 CSCD 2014年第4期1-5,共5页
云白3号是采用常规杂交选择途径而育成的白肋烟新品种,2010年经全国烟草新品种农业评审,2012年通过全国烟草新品种审定。该品种生长整齐,长势强,有效叶较多,农艺性状表现较好。较耐肥,适应性较强。高抗TMV,中抗黑胫病,中感南方根结线虫... 云白3号是采用常规杂交选择途径而育成的白肋烟新品种,2010年经全国烟草新品种农业评审,2012年通过全国烟草新品种审定。该品种生长整齐,长势强,有效叶较多,农艺性状表现较好。较耐肥,适应性较强。高抗TMV,中抗黑胫病,中感南方根结线虫病,感赤星病。主要经济性状表现较优。全国品种区域试验结果表明,产量、产值在4省区具有良好的稳定性和丰产性。烟叶总体外观质量、物理特性略优于对照,化学成分协调性、感官质量与对照相当。 展开更多
关键词 白肋烟 云白3号 选育 特征特性 Yunbai3
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“云白一号”大白菜的选育 被引量:1
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作者 肖祥 严家芸 《长江蔬菜》 北大核心 1993年第2期30-31,共2页
大白菜是云南省中部和南部一年四季栽培的主要蔬菜。由于长期以来品种单一,而引进的早熟品种多不适应,又常因种子质量和数量不能满足需要。
关键词 大白菜 云白一号 品种 育种
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玉米杂交新品种云白3号的选育 被引量:1
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作者 江兵 高志宏 +2 位作者 郭贵敏 田飞 李荣 《耕作与栽培》 2021年第4期101-102,共2页
云白3号是云南霖鹏农业科技有限公司和贵州禾睦福种子有限公司用外引自育自交系SC 234作父本(水白玉1号母本,品种审定编号:黔审玉2017013),自育自交系2162作母本组配的杂交玉米新品种。于2015冬在海南组配成功,2018年参加贵州省高山组... 云白3号是云南霖鹏农业科技有限公司和贵州禾睦福种子有限公司用外引自育自交系SC 234作父本(水白玉1号母本,品种审定编号:黔审玉2017013),自育自交系2162作母本组配的杂交玉米新品种。于2015冬在海南组配成功,2018年参加贵州省高山组绿色通道玉米区域试验,2020年通过贵州省农作物品种审定委员会审定,审定编号:黔审玉202013。 展开更多
关键词 云白3号 选育 玉米杂交种
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Mechanism of extracting magenesium from mixture of calcined magnesite and calcined dolomite by vacuum aluminothermic reduction 被引量:6
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作者 傅大学 王耀武 +3 位作者 彭建平 狄跃忠 陶绍虎 冯乃祥 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第8期2677-2686,共10页
The process of aluminothermic reduction of a mixture of calcined dolomite and calcined magnesite had been developed. The mechanism of the process was studied by SEM and EDS. The reduction process was divided into thre... The process of aluminothermic reduction of a mixture of calcined dolomite and calcined magnesite had been developed. The mechanism of the process was studied by SEM and EDS. The reduction process was divided into three stages:0≤ηt/ηf≤0.43±0.06, 0.43±0.06≤ηt/ηf≤0.9±0.02 and 0.9±0.02≤ηt/ηf<1, whereηt andηf are the reduction ratio at time t and the final reduction ratio obtained in the experiment at temperature T, respectively. The first stage included the direct reaction between calcined dolomite or calcined magnesite and Al with 12CaO·7Al2O3 and MgO·Al2O3 as products. The reaction rate depended on the chemical reaction. The CA phase was mainly produced in the second stage and the overall reaction rate was determined by both the diffusion of Ca2+ with molten Al and the chemical reaction. The CA2 phase was mainly produced in the third stage and the reaction process was controlled by the diffusion of Ca2+. 展开更多
关键词 magnesium aluminothermic reduction MAGNESITE DOLOMITE MECHANISM
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Kinetics of extracting magnesium from mixture of calcined magnesite and calcined dolomite by vacuum aluminothermic reduction 被引量:7
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作者 傅大学 冯乃祥 +2 位作者 王耀武 彭建平 狄跃忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期839-847,共9页
The vacuum aluminothermic reduction of the mixture of calcined magnesite and calcined dolomite was studied. An isothermal reduction method satisfying the vacuum aluminothermic reduction was proposed. The experiments w... The vacuum aluminothermic reduction of the mixture of calcined magnesite and calcined dolomite was studied. An isothermal reduction method satisfying the vacuum aluminothermic reduction was proposed. The experiments were carried out at 4 Pa. The results indicate that the reduction rate is increased with increasing temperature, content of aluminum and pellet forming pressure. The XRD patterns of pellets at different reduction stages confirm that the reduction process can be roughly classified into three stages:the formation of MgAl2O4, and Ca12Al14O33 phases;the phase transformation from MgAl2O4 and C12A7 to CaAl2O4;the formation of CaAl4O7 phase. The experimental data were divided into three parts according to the kinetic models. The apparent activation energies of the three parts were determined to be 98.2, 133.0 and 223.3 kJ/mol, respectively. 展开更多
关键词 Amagnesium KINETICS aluminothermic reduction MAGNESITE DOLOMITE
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高校研讨型智慧教室的构建与应用 被引量:8
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作者 吕恋生 杨再明 张凯 《中国教育信息化》 2019年第21期69-72,共4页
随着高校智慧校园建设步伐的加快,功能多样的智慧教室相继建成,在完善教学功能的同时,教学设备数量也成倍增长,系统集成越来越复杂,管理维护量激增,加之大多数高校需要承担考试任务,平衡教学个性化与考场标准化之间的关系,所以此类智慧... 随着高校智慧校园建设步伐的加快,功能多样的智慧教室相继建成,在完善教学功能的同时,教学设备数量也成倍增长,系统集成越来越复杂,管理维护量激增,加之大多数高校需要承担考试任务,平衡教学个性化与考场标准化之间的关系,所以此类智慧教室较难实现大批量建设。同时,传统教室无法满足教育现代化发展趋势,难以融入智慧校园建设整体框架,教室的智慧化改造又势在必行。因此,中国矿业大学设计构建了研讨型智慧教室,该类教室以简捷高效为设计理念,以人性化为设计宗旨,既方便教师使用又利于管理维护,同时满足考试需求,以一键式、自动化、远程控制为技术基础,利用软件平台实现互动式、个性化教学。 展开更多
关键词 智慧教室 研讨型教室 双屏教学 云白
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Molecular Detection of Resistance Genes to Stripe Rust and Powdery Mildew in Common Wheat Cultivar Yunmai52 被引量:1
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作者 李宏生 谭丽明 +7 位作者 赵红 吴绍柱 杨素梅 张志强 丁明亮 顾坚 杨木军 李绍祥 《Agricultural Science & Technology》 CAS 2016年第4期801-803,809,共4页
Yunmai52, developed by crossing with common wheat-Haynaldia villosa6AL/6VS translocation line 92R149 as a resistant parent in 1992, was a common wheat cultivar approved and released in 2007 in Yunnan Province, China, ... Yunmai52, developed by crossing with common wheat-Haynaldia villosa6AL/6VS translocation line 92R149 as a resistant parent in 1992, was a common wheat cultivar approved and released in 2007 in Yunnan Province, China, which is characterized by high resistance to powdery mildew and stripe rust. In this study,an F_2 population derived from a cross K78S/Yunmai52 was constructed to investigate the resistance genes, where K78 S is a wheat male sterile line susceptible to powdery mildew and stripe rust. Phenotypic identification of the parents, F_1 and F_2 populations and chi-square analyses showed that F_1 population was immune to stripe rust and powdery mildew; the segregation ratio of resistance and susceptibility to powdery mildew(χ~2=1.10χ~2_(1,0.05)=3.84) and stripe rust(χ~2=0.15χ~2_(1,0.05)=3.84) fit to a 3:1 ratio in F_2 population, indicating that Yunmai52 harbors a dominant stripe rust resistance gene and a dominant powdery mildew resistance gene. The individuals were further detected with a marker co-segregated with Pm21(SCAR_(1400)) and two markers closely linked with Yr26(XWe173 and Xbarc181). The results showed that polymorphic bands could be amplified between the parents and between resistance and susceptibility gene pools at the same locus. Randomly 96 individuals of F_2 population were selected for verification. The results showed that the phenotype was significantly correlated with the genotype. The detection accuracy of markers SCAR_(1400), XWe173 and Xbarc181 was 100%, 97.91% and 92.70%, respectively.Yunmai52 harbored powdery mildew resistance gene Pm21 and stripe rust resistance gene Yr26, which were both derived from 6AL/6VS translocation line 92R149.In addition, the results also demonstrate that Pm21 and Yr26 are two genes conferring durable resistance to powdery mildew and stripe rust in wheat. 展开更多
关键词 WHEAT Yunmai52 Powdery mildew Stripe rust Resistance gene
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试探《穆天子传》传入日本的时间及途径 被引量:1
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作者 刘伏玲 王齐洲 《华中师范大学学报(人文社会科学版)》 CSSCI 北大核心 2015年第4期98-104,共7页
伊与部马养在《从驾应诏》诗中提到"瑶池"和"白云篇",而"瑶池"与"白云谣"典故出自《穆天子传》,明示他受到《穆天子传》影响。伊与部马养是有文献可证的《穆天子传》在日本的早期接受者,其接... 伊与部马养在《从驾应诏》诗中提到"瑶池"和"白云篇",而"瑶池"与"白云谣"典故出自《穆天子传》,明示他受到《穆天子传》影响。伊与部马养是有文献可证的《穆天子传》在日本的早期接受者,其接受时间在持统天皇702年逝世之前。731年葛井连广成奉试对策提到了"黄竹"和"白云","黄竹"典故也出自《穆天子传》,说明日本上层对《穆天子传》已很熟悉。日本学者在诗文中引用《穆天子传》,既与他们注意学习《昭明文选》和李善注有关,也与他们直接阅读《穆天子传》有关。《文选》李善注本可能不是直接从唐朝传入日本,而是通过新罗间接传入。《穆天子传》则更有可能是由日本遣隋使团、遣唐使团中的学问僧与留学生带回日本。基于此,笔者将《穆天子传》传至日本的时间上限定为隋文帝开皇二十年(600年),日本圣德太子初次派遣留学生到中国留学;下限则为日本持统天皇逝世之年,即武则天长安二年(702年)。具体时间难以确考。 展开更多
关键词 《穆天子传》 伊与部马养 《从驾应诏》 葛井连广成 白云谣 黄竹诗
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Innovative Practice of Science and Technology Supported Western Village Public Cultural Services in China
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作者 于开锋 金颖若 《Agricultural Science & Technology》 CAS 2017年第12期2628-2632,共5页
The shortage and inefficiency of public cultural services are common problems in China, especially in the western regions. Baiyun District has made use- ful exploration to the construction of rural public cultural ser... The shortage and inefficiency of public cultural services are common problems in China, especially in the western regions. Baiyun District has made use- ful exploration to the construction of rural public cultural service system, network system, resource system, management system and service system. 展开更多
关键词 Public cultural service Western villages Science and technology Baiyun District
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两种去白膜法制备的洗涤红细胞结果对比
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作者 周国芳 《交通医学》 2000年第3期271-271,共1页
关键词 云白膜法 制备 洗涤红细胞 输血反应
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Mineral Elements in Different Varieties of Camellia sinensis 被引量:15
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作者 李春华 王云 《Agricultural Science & Technology》 CAS 2009年第1期105-107,共3页
To understand the mineral elements in different varieties of tea ( Camellia sinensis), 17 mineral elements in eight tea varieties including Yunnan Dayezhong, No. 43 Longjing and No. 6 Zaobaijian, were measured. The ... To understand the mineral elements in different varieties of tea ( Camellia sinensis), 17 mineral elements in eight tea varieties including Yunnan Dayezhong, No. 43 Longjing and No. 6 Zaobaijian, were measured. The results showed that nine elements, such as P, K, Ba, Mn, Cu, were significantly different among varieties, others did not. Black tea varieties usually contain high contents of Cu and K. As a conclusion, mineral elements should be extensively considered in breeding tea varieties. 展开更多
关键词 Camellia sinensis BREEDING Mineral element
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Selective flotation of smithsonite from dolomite by using novel mixed collector system 被引量:9
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作者 Li WANG Guang-yan HU +3 位作者 Wei SUN SultanAhmed KHOSO Run-qing LIU Xiang-feng ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第5期1082-1089,共8页
A novel mixed collector (BHOA) was prepared by mixing benzohydroxamic acid (BHA) and sodium oleate (NaOL) and applied to the flotation separation of smithsonite from dolomite. Flotation results showed that NaOL alone ... A novel mixed collector (BHOA) was prepared by mixing benzohydroxamic acid (BHA) and sodium oleate (NaOL) and applied to the flotation separation of smithsonite from dolomite. Flotation results showed that NaOL alone had good collecting performance on smithsonite and common gangue mineral dolomite but had poor selectivity. By using a BHA/NaOL mixed system with a molar ratio of 2:1, the recoveries of smithsonite and dolomite reached approximately 90% and 5%, respectively. Surface tension analysis showed that the surface activity of BHOA was a little higher than that of a single NaOL because of synergistic effects. Zeta potential and X-ray photoelectron spectroscopy measurements indicated that surfactants BHA and NaOL co-absorbed on the smithsonite surface and only NaOL was present on the dolomite surface in the presence of BHOA. 展开更多
关键词 FLOTATION SMITHSONITE DOLOMITE sodium oleate benzohydroxamic acid SULFURATION
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Potassium recovery from muscovite using NaCl-roasting followed by H_(2)SO_(4)-leaching 被引量:3
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作者 Sandeep Kumar JENA Baijayantimala MOHANTY +2 位作者 Geetikamayee PADHY Jogeshwara SAHU Sapan Kumar KANDI 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第6期1881-1894,共14页
The present study aims at the recovery of potassium from muscovite mica(which contains K_(2)O;~10 wt%)using NaCl-roasting coupled with H_(2)SO_(4)-leaching process.The preliminary acid leaching studies applying differ... The present study aims at the recovery of potassium from muscovite mica(which contains K_(2)O;~10 wt%)using NaCl-roasting coupled with H_(2)SO_(4)-leaching process.The preliminary acid leaching studies applying different mineral acids resulted in a potassium recovery of 8%−18%.The optimum leaching conditions for the maximum recovery were 4 mol/L H_(2)SO_(4),60 min leaching time and liquid-solid ratio 4 mL/g at 90℃.However,the roasting of muscovite with additive NaCl(muscovite:NaCl mass ratio of 1:1.00,900℃,45 min)followed by H_(2)SO_(4)-leaching(95℃,60 min)extracted potassium to the tune of 98%.Under similar roasting conditions,the H_(2)O-leaching process extracted only 60%of potassium.The effects of various roasting and leaching parameters such as temperature,time,NaCl concentration,acid concentration,liquid-solid ratio on potassium extraction were evaluated.The appearance of the sylvite(KCl)mineral phase in the NaCl-roasted muscovite and its disappearance in the acid/water leached residue confirmed the physical and chemical distortions of the muscovite crystal structure.The possible mechanism of potassium release from the complex muscovite structure was elucidated based on available literature substantiated by characterizations using X-ray diffraction(XRD)and scanning electron microscopy with energy dispersive X-rays spectroscopy(SEM-EDX). 展开更多
关键词 MUSCOVITE ROASTING acid leaching potassium recovery SYLVITE
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Muscovite 40Ar-39Ar age and its geological significance in Zhuxi W(Cu) deposit, northeastern Jiangxi 被引量:9
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作者 OUYANG Yong-peng WEI Jin +5 位作者 LU Yi ZHANG Wei YAO Zai-yu RAO Jian-feng CHEN Guo-hua PAN Xiao-fei 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第12期3488-3501,共14页
The Zhuxi W(Cu)skarn deposit,the world’s largest tungsten deposit is newly discovered in Jingdezhen city,northeastern Jiangxi province,China.It mainly occurs near the contact zone between the Yanshanian granites and ... The Zhuxi W(Cu)skarn deposit,the world’s largest tungsten deposit is newly discovered in Jingdezhen city,northeastern Jiangxi province,China.It mainly occurs near the contact zone between the Yanshanian granites and the Late Paleozoic carbonate rocks.Three types of mineralization including skarn type,altered granite type and quartz vein veinlet type orebodies have been observed.In this study,the 40Ar 39Ar age of hydrothermal muscovite coexisting with copper mineralization in the altered granite type orebody formed near the unconformity interface is determined by step-heating technology using CO2 laser.The plateau age,isochron age,and inverse isochron age of muscovite are(147.39±0.94)Ma,(147.2±1.5)Ma,and(147.1±1.5)Ma,respectively.These ages are almost identical to the ages of ore-related granite and other mineralization types in the Zhuxi W(Cu)deposit,indicating that the Cu mineralizations occurred at the shallow depth and near the unconformity interface are contemporaneous during the Late Jurassic.This further suggested that the acompanied W and Cu mineralization in the Zhuxi W(Cu)deposit which may be controlled by the magma source is enriched in both W and Cu. 展开更多
关键词 MUSCOVITE 40Ar 39Ar age altered granite-type orebody Zhuxi W(Cu)deposit northeastern Jiangxi
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Matrix porosity calculation in volcanic and dolomite reservoirs and its application 被引量:7
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作者 Li Ning Wu Hongliang +4 位作者 Feng Qingfu Wang Kewen Shi Yujiang Li Qingfeng Luo Xinping 《Applied Geophysics》 SCIE CSCD 2009年第3期287-298,301,共13页
Matrix porosity calculations of fractured and vuggy reservoirs, such as volcanics and weathered dolomite, are one of the problems urgently needed to solve in well-log evaluation. In this paper, we first compare the an... Matrix porosity calculations of fractured and vuggy reservoirs, such as volcanics and weathered dolomite, are one of the problems urgently needed to solve in well-log evaluation. In this paper, we first compare the an empirical formula for porosity calculation from full diameter rhyolite core experiments with the matrix porosity formulas commonly used. We discuss the applicability of the empirical formula in fractured and vuggy reservoirs, such as intermediate-basic volcanics and weathered dolomite. Based on core analysis data, the error distribution of the calculated porosity of our empirical formula and the other porosity formulas in these reservoirs are given. The statistical error analysis indicates that the our empirical formula provides a higher precision than the other porosity formulas. When the porosity is between 1.5% and 15%, the acoustic experiment formula can be used not only for acidic volcanics but also in other fractured and vuggy reservoirs, such as intermediate-basic volcanics and weathered dolomite. Moreover, the formula can reduce the effects of borehole enlargement and rock alteration on porosity computation. 展开更多
关键词 POROSITY acoustic slowness VOLCANICS CARBONATES
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Focused fluid flow in the Baiyun Sag, northern South China Sea: implications for the source of gas in hydrate reservoirs 被引量:11
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作者 陈端新 吴时国 +3 位作者 董冬冬 米立军 付少英 施和生 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期178-189,共12页
The origin and migration of natural gas and the accumulation of gas hydrates within the Pearl River Mouth Basin of the northern South China Sea are poorly understood. Based on high-resolution 2D/3D seismic data, three... The origin and migration of natural gas and the accumulation of gas hydrates within the Pearl River Mouth Basin of the northern South China Sea are poorly understood. Based on high-resolution 2D/3D seismic data, three environments of focused fluid flow: gas chimneys, mud diapirs and active faults have been identified. Widespread gas chimneys that act as important conduits for fluid flow are located below bottom simulating reflections and above basal uplifts. The occurrence and evolution of gas chimneys can be divided into a violent eruptive stage and a quiet seepage stage. For most gas chimneys, the strong eruptions are deduced to have happened during the Dongsha Movement in the latest Miocene, which are observed below Pliocene strata and few active faults develop above the top of the Miocene. The formation pressures of the Baiyun Sag currently are considered to be normal, based on these terms: 1) Borehole pressure tests with pressure coefficients of 1.043-l.047; 2) The distribution of gas chimneys is limited to strata older than the Pliocene; 3) Disseminated methane hydrates, rather than fractured hydrates, are found in the hydrate samples; 4) The gas hydrate is mainly charged with biogenic gas rather than thermogenic gas based on the chemical tests from gas hydrates cores. However, periods of quiet focused fluid flow also enable the establishment of good conduits for the migration of abundant biogenic gas and lesser volumes ofthermogenic gas. A geological model goveming fluid flow has been proposed to interpret the release of overpressure, the migration of fluids and the formation of gas hydrates, in an integrated manner. This model suggests that gas chimneys positioned above basal uplifts were caused by the Dongsha Movement at about 5.5 Ma. Biogenic gas occupies the strata above the base of the middle Miocene and migrates slowly into the gas chimney columns. Some of the biogenic gas and small volumes ofthermogenic gas eventually contribute to the formation of the gas hydrates. 展开更多
关键词 gas hydrate thermogenic gas biogenic gas Dongsha Movement focused fluid flow SouthChina Sea
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GRADIENT DISTRIBUTION OF ACID RAIN IN THE SCENIC RESORT OF THE BAIYUN MOUNTAIN IN GUANGZHOU 被引量:1
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作者 黄健 李福娇 +1 位作者 江奕光 李琼 《Journal of Tropical Meteorology》 SCIE 2004年第1期95-105,共11页
This paper analyzes the samples of rainwater from January to October 1999 at three monitoring sites of Baiyun Mountain and of aerosol composition in near-surface layer in January and June 1999 at two sites. The result... This paper analyzes the samples of rainwater from January to October 1999 at three monitoring sites of Baiyun Mountain and of aerosol composition in near-surface layer in January and June 1999 at two sites. The results suggest that (1) The pH value of rainwater is between 3.13 and 7.18, and the frequency of acid rain is more than 58 %. With the ascent of the monitoring sites, the pH value of rainwater decreases, and the frequency of acid rain increases. (2) In January, the chemical aerosol compositions at different altitudes are similar, but in June the acidity of aerosol rises at the higher site because of the increase of SO42-. (3) In rainwater, the proportion is such that SO42- is the most significant anion and Ca2+ is the most important cation, but both of them decrease as the altitude ascends. The proportion of NO3- and NH4+ rise at the higher site and have more contribution to the acidity of rainwater. (4) As the impact of automobile emissions around Baiyun Mountain, the proportion of NO3-/SO42-molecular concentration reaches 0.40, and NO3- is relatively more important to the rain acidity at the higher site. 展开更多
关键词 Baiyun Mountain RAINWATER aerosol chemical composition
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Element geochemical characteristics of a soil profile developed on dolostone in central Guizhou, southern China: implications for parent materials 被引量:5
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作者 Xingxing Cao Pan Wu Zhenxing Cao 《Acta Geochimica》 EI CAS CSCD 2016年第4期445-462,共18页
This study presents bulk chemical compositions of the Tongmuling soil profile, which developed on dolostone, and the overlying strata covering the bedrock in the central Guizhou province(southern China). The chemical ... This study presents bulk chemical compositions of the Tongmuling soil profile, which developed on dolostone, and the overlying strata covering the bedrock in the central Guizhou province(southern China). The chemical weathering characteristics of the studied profile were investigated and the inheritance relationships between the terra rossa and overlying strata were discussed. The results show that there is no remarkable variation in the major elements and weathering indices from the rock–soil interface to the topsoil, indicating that the studied profile was not typical for in situ crustal chemical weathering. The terra rossa were mainly composed of Si O_2, Al_2O_3 and Fe_2O_3. Compared with the insoluble residues and overlying strata, the terra rossa are characterized by an enrichment of Y and Cs and depletion of Ba and Sr. The subsoil shows a notable Ce negative anomaly, characterized by heavy rare earth element enrichment(L/H = 1.55–3.74), whereas the topsoil shows a positive Ce anomaly with light rare earth element enrichment(L/H = 5.93–9.14). According to Laterite-forming capacity estimates, the terra rossa could not have only been formed from acid-insoluble residues from the bedrock; Al_2O_3 versus Fe_2O_3and Nb plotted against Ta show significant positive correlations between the terra rossa and overlying strata. The Eu/Eu* versusGd_N/Yb_Nand ternary diagrams for Sc, Th, Zr, and Ta suggest that the overlying strata could also provide parent materials for the genesis of terra rossa. 展开更多
关键词 Terra rossa DOLOMITE Parent materials GUIZHOU China
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Formation mechanism of reservoir oolitic dolomite in Lower Triassic Feixianguan formation, northeastern Sichuan Basin, southwest China 被引量:5
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作者 陈培元 谭秀成 +5 位作者 刘宏 马腾 罗冰 姜兴福 于洋 靳秀菊 《Journal of Central South University》 SCIE EI CAS 2014年第8期3263-3274,共12页
A series of marine natural gas fields were recently discovered in oolitic dolomites of the Lower Triassic Feixianguan formation, northeastern Sichuan Basin, southwest China. The mechanism forming these reservoir dolom... A series of marine natural gas fields were recently discovered in oolitic dolomites of the Lower Triassic Feixianguan formation, northeastern Sichuan Basin, southwest China. The mechanism forming these reservoir dolomites is debatable, limiting the ability to characterize these reservoir successfully. Based on the investigation of the representative Dukouhe, Luojiazhai, and Puguang areas, this issue was addressed by examining the distribution, petrology, and geochemistry of the dolomites, the most comprehensive study to date was provided. Dolomitization occurred at a very early stage of diagenesis, as shown by the petrological features of the rock fabric. Vadose silt, which is composed primarily of dolomitic clasts, is found in the primary and secondary pores of the oolitic dolomite. This indicates that the overlying strata were subjected to dolomitization when the Feixianguan formation was located in the vadose zone. Therefore, it may be inferred that the dolomitization which occurred before the formation was exposed to meteoric conditions. The spatial distribution and geochemical characteristics of the dolomite indicate that dolomitization occurred as a result of seepage reflux. The degree of dolomitization decreases with increasing distance from the evaporative lagoon. Furthermore, the type and porosity of the dolomite vary in different zones of the upward-shoaling sequence, with the porosity gradually decreasing from the highest layer to the lowest layer. This reflects a close relationship between dolomitization and seawater evaporation during the formation of the dolomite. Geochemical analysis provided further evidence for the relationship between the dolomitization fluid and the coeval seawater. The 87Sr/86Sr and 813C isotopes, as well as the abundances of trace elements, Fe and Mn, indicate that seawater concentrated by evaporation acted as the dolomitization fluid. These results also show that dolomitization most likely occurred in a semi-closed diagenetic environment. Therefore, the main mechanism of oolitic dolomite formation is seepage reflux, which occurred at an early stage of diagenesis. 展开更多
关键词 Lower Triassic Feixianguan formation early exposure seepage reflux DOLOMITIZATION Sichuan Basin northeastern Sichuan
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