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皖南解带山铅锌矿成矿岩体锆石U-Pb年代学研究及地质意义
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作者 白茹玉 黄永海 《四川有色金属》 2024年第3期55-58,共4页
解带山铅锌矿位于皖南铅锌成矿区,本文对解带山花岗闪长斑岩含矿岩体开展了岩相学和锆石U-Pb年代学研究,获得锆石U-Pb年龄为136.4±1.4 Ma,形成于早白垩世,属燕山晚期岩浆活动产物,花岗闪长斑岩相对较低的结晶温度和相对中等的氧逸... 解带山铅锌矿位于皖南铅锌成矿区,本文对解带山花岗闪长斑岩含矿岩体开展了岩相学和锆石U-Pb年代学研究,获得锆石U-Pb年龄为136.4±1.4 Ma,形成于早白垩世,属燕山晚期岩浆活动产物,花岗闪长斑岩相对较低的结晶温度和相对中等的氧逸度有利于铅锌沉淀成矿。 展开更多
关键词 皖南 铅锌矿 成矿岩体 年代学
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磷灰石ID-TIMS高精度U-Pb定年方法
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作者 涂家润 周红英 +3 位作者 崔玉荣 李国占 耿建珍 张健 《岩矿测试》 CAS CSCD 北大核心 2024年第4期533-545,共13页
磷灰石晶体结构呈六方晶系,具有相对高的封闭温度(350~550℃),能够容纳多种元素置换进入晶格内部,是火成岩、沉积岩、变质岩和矿床研究的重要定年矿物。然而,由于磷灰石通常具有较低铀含量和高普通铅含量,精准测定其年龄仍是当前U-Pb测... 磷灰石晶体结构呈六方晶系,具有相对高的封闭温度(350~550℃),能够容纳多种元素置换进入晶格内部,是火成岩、沉积岩、变质岩和矿床研究的重要定年矿物。然而,由于磷灰石通常具有较低铀含量和高普通铅含量,精准测定其年龄仍是当前U-Pb测年技术的一大挑战。本文基于^(208)Pb-^(235)U混合稀释剂,通过优化样品清洗、溶解以及柱色谱分离纯化U和Pb等化学前处理流程,建立了磷灰石同位素稀释-热电离质谱(ID-TIMS)高精度U-Pb定年方法,并准确测定了磷灰石标样MAD2和MAP-3的年龄,其^(206)Pb/^(238)U年龄加权平均值分别为474.6±1.7Ma和800.7±1.2Ma,单点定年精度优于0.4%,为磷灰石微区原位标样研发以及样品年龄精准测定提供技术支撑。采用MAP-3作为微区原位校正标样,对磷灰石Durango和Otter Lake进行LA-ICP-MS U-Pb测年分析,通过Tera-Wasserburg谐和图图解法扣除普通铅,获得下交点年龄分别为32.1±0.6Ma(MSWD=1.3,n=36)和910±13Ma(MSWD=1.6,n=36),与前人研究结果在误差范围内一致,进一步证实普通铅含量极低的MAP-3,是一个理想的磷灰石微区原位测年标样。与高普通铅的磷灰石标样相比,使用MAP-3作为外标能直接在数据处理软件中进行数据校正,有效地简化了数据处理过程,提高磷灰石微区原位U-Pb测年结果的可靠性。 展开更多
关键词 同位素稀释-热电离质谱法 U-pb定年 稀释剂 普通铅 标样
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水相单层氨基改性二氧化硅的制备及Pb^(2+)吸附效果
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作者 韩璐 叶杰铭 +2 位作者 杨玉琼 王景元 肖海成 《石化技术与应用》 CAS 2024年第5期324-329,共6页
采用硅烷偶联剂γ-氨丙基三乙氧硅烷(APTES)和(β-氨乙基)-γ-氨丙基三甲氧基硅烷(AEAPTMS),通过水相工艺分别制备出单层氨基改性二氧化硅(SiO_(2)-APTES和SiO_(2)-AEAPTMS,用作吸附剂),采用透射电子显微镜、红外光谱分析仪、热重-差热... 采用硅烷偶联剂γ-氨丙基三乙氧硅烷(APTES)和(β-氨乙基)-γ-氨丙基三甲氧基硅烷(AEAPTMS),通过水相工艺分别制备出单层氨基改性二氧化硅(SiO_(2)-APTES和SiO_(2)-AEAPTMS,用作吸附剂),采用透射电子显微镜、红外光谱分析仪、热重-差热分析仪、元素分析仪等仪器对其进行了表征,考察了Pb^(2+)吸附效果的影响因素,确定了最佳吸附条件。结果表明:当偶联剂添加量(质量分数)小于15%时,可实现二氧化硅的单层氨基改性;在初始Pb^(2+)质量浓度为200 mg/L,pH值为6,吸附时间为60 min的优化条件下,SiO_(2)-APTES和SiO_(2)-AEAPTMS对Pb^(2+)的最大吸附量分别达到18.48,34.75 mg/g;吸附过程均符合拟二级动力学模型和Langmuir吸附模型,均为单分子层的化学吸附过程;吸附剂重复使用5次后,Pb^(2+)吸附量仍超过最大吸附量的90%,具有良好的循环使用性能。 展开更多
关键词 二氧化硅 硅烷偶联剂 氨基改性 铅离子(pb^(2+)) 吸附效果
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Pb-Ca合金板栅电池早期容量衰减的原因
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作者 谭晓波 李江 +3 位作者 王杜友 郭志刚 卢晓华 杨建芬 《电池》 CAS 北大核心 2024年第4期525-528,共4页
Pb-Ca合金在阀控式铅酸(VRLA)电池中应用广泛。针对Pb-Ca合金浇铸板栅电池的早期容量衰减问题进行研究。用同批次Pb-Ca合金极板,制作不同加酸化成工艺的电池,进行循环测试。充电电流小的电池发生了早期容量衰减,而大电流充电的电池循环... Pb-Ca合金在阀控式铅酸(VRLA)电池中应用广泛。针对Pb-Ca合金浇铸板栅电池的早期容量衰减问题进行研究。用同批次Pb-Ca合金极板,制作不同加酸化成工艺的电池,进行循环测试。充电电流小的电池发生了早期容量衰减,而大电流充电的电池循环性能正常。对发生早期容量衰减的电池进行分析,发现板栅腐蚀界面生成的硫酸铅晶体阻挡层是导致电池发生早期容量衰减的主要原因。提高电池的充电效率,如添加电解液添加剂、化成前对电池反充、增大充电电流等,可以使硫酸铅得以转化,能较好地避免电池发生早期容量衰减。 展开更多
关键词 阀控式铅酸(VRLA)电池 早期容量衰减 pb-Ca合金 板栅 硫酸铅 电解液添加剂 循环性能
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蒙古国查夫铅锌矿锆石U-Pb年代学、岩石地球化学及构造意义
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作者 王宏明 《资源信息与工程》 2024年第1期22-25,29,共5页
通过岩石地球化学研究,蒙古国查夫铅锌矿侵入岩石体为过铝质、高钾钙碱性系列,主体为S型花岗岩,且存在I型花岗岩,反映了岩浆活动的多样性。同时,成矿岩体富集Rb、Ba、Th、U、K和Pb等大离子亲石元素(LILE),亏损Nb、Ta、Ti等高场强元素(HF... 通过岩石地球化学研究,蒙古国查夫铅锌矿侵入岩石体为过铝质、高钾钙碱性系列,主体为S型花岗岩,且存在I型花岗岩,反映了岩浆活动的多样性。同时,成矿岩体富集Rb、Ba、Th、U、K和Pb等大离子亲石元素(LILE),亏损Nb、Ta、Ti等高场强元素(HFSE),显示出岛弧岩浆作用的特征。构造识别认为研究区内花岗岩形成于岛弧、陆缘弧环境,与大陆碰撞造山、后造山构造作用相关,形成年龄为(238±4)Ma(MSWD=3.8),形成时代属中三叠世。 展开更多
关键词 蒙古国查夫铅锌矿 U-pb年代学 地球化学 构造环境
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石榴子石的LA-ICP-MS面扫描U-Th-Pb定年——以铜绿山大型Cu-Fe-Au矽卡岩矿床为例 被引量:1
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作者 葛粲 汤笑伟 +5 位作者 汪方跃 李修钰 孙贺 顾海欧 袁峰 郑辉 《岩石学报》 SCIE EI CAS CSCD 北大核心 2023年第10期2879-2894,共16页
矽卡岩矿床的年代学信息对研究矽卡岩矿床的矿床成因、演变过程、成矿规律和找矿勘查具有重要的指示意义。石榴子石是矽卡岩矿床中的常见矿物,它具有一定的U含量,但是由于其普通铅高以及铀分布不均一的原因,导致激光剥蚀电感耦合等离子... 矽卡岩矿床的年代学信息对研究矽卡岩矿床的矿床成因、演变过程、成矿规律和找矿勘查具有重要的指示意义。石榴子石是矽卡岩矿床中的常见矿物,它具有一定的U含量,但是由于其普通铅高以及铀分布不均一的原因,导致激光剥蚀电感耦合等离子体质谱仪(LA-ICP-MS)点分析获得年龄成功率不高。针对点分析定年遇到的深度分馏和剥蚀点选取、普通铅校正等问题,本文提出一种利用LA-ICP-MS面扫描分析数据的虚拟点构建技术,在Tera-Wasserburg(TW)图中实现普通铅校正来确定含普通铅石榴子石年龄。通过理论推导、数值模拟和实验分析研究发现,利用相关联的^(208)Pb、^(232)Th、^(238)U测量数据校正生成^(208)Pb_(c)/^(238)U指标并据此对TW图中的数据进行数据分组抽样构造虚拟测量点,可以有效地把面扫描测量数据转换为与点分析测量类似但放射母子比例展布更优的数据。利用此方法对长江中下游成矿带鄂东矿区铜绿山大型Cu-Fe-Au矽卡岩矿床石榴子石进行面扫描分析。仅使用15min的样品面扫描数据,在获得了微量元素含量分布的同时,也获得了同位素比值虚拟点,交点年龄为139.2±2.9Ma(MSWD=0.7,n=126),与前人矿床研究结果相一致,验证了此方法的可行性。利用LA-ICP-MS面扫描定年技术不仅可以获得样品元素含量的二维分布图,有利于对样品期次的筛选,剔除包裹体等异常数据;还可以避免点分析中深度分馏和繁复的选点流程及二次分析等步骤,在获得样品元素含量分布的同时获得矿物年龄,为当前矽卡岩型矿床相关的关键金属研究提供了更为便捷的方法。 展开更多
关键词 含普通铅矿物U-Th-pb定年 LA-ICP-MS面扫描技术 关键金属 石榴子石年代学 矽卡岩 铜绿山
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Toxicity threshold of lead(Pb) to nitrifying microorganisms in soils determined by substrate-induced nitrification assay and prediction model 被引量:2
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作者 ZHENG Han CHEN Li +4 位作者 LI Ning LIU Bin MENG Nan WANG Meng CHEN Shi-bao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第8期1832-1840,共9页
Lead (Pb) contamination has often been recorded in Chinese field soils. In recent years, efforts have been made to inves- tigate Pb toxicity thresholds in soils with plant growth and microbial assays. However, the i... Lead (Pb) contamination has often been recorded in Chinese field soils. In recent years, efforts have been made to inves- tigate Pb toxicity thresholds in soils with plant growth and microbial assays. However, the influence of soil properties on Pb toxicity impacts on soil microbial processes is poorly understood. In this study ten soils with different properties were collected in China to investigate the relationships between thresholds of Pb toxicity to soil microbes and soil properties. The effect of soil leaching on Pb toxicity was also investigated to determine the possible influence of added anions on Pb toxicity during dose-response tests. Toxicity was inferred by measuring substrate-induced nitrification in leached and non-leached soils after Pb addition. We found that soil microbe Pb toxicity thresholds (ECx, x=10, 50) differed significantly between the soils; the 10% inhibition ratio values (ECI0) ranged from 86 to 218 mg kg-1 in non-leached soils and from 101 to 313 mg kg in leached soils. The 50% inhibition ratio values (EC50) ranged from 403 to 969 mg kg^-1 in non-leached soils and from 494 to 1 603 mg kg^-1 in leached soils. Soil leaching increased EC50 and EC50 values by an average leaching factor (LF) of 1.46 and 1.33, respectively. Stepwise multiple regression models predicting Pb toxicity to soil microbes were developed based on ECx and soil properties. Based on these models, soil pH and organic carbon are the most important soil properties af- fecting Pb toxicity thresholds (R2〉0.60). The quantitative relationship between Pb toxicity and soil properties will be helpful for developing soil-specific guidance on Pb toxicity thresholds in Chinese field soils. 展开更多
关键词 DOSE-RESPONSE lead pb polluted soil substrate-induced nitrification
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Effects of lead(Pb)-induced oxidative stress on morphological and physio-biochemical properties of rice 被引量:1
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作者 MURTAZA KHAN IBA NAZAR IBRAHIM AL AZZAWI +4 位作者 MUHAMMAD IMRAN ADIL HUSSAIN BONG-GYU MUN ANJALI PANDE BYUNG-WOOK YUN 《BIOCELL》 SCIE 2021年第5期1413-1423,共11页
In rice,high concentration of lead(Pb)can cause phyto-toxicity affecting several physiological functions.Cultivation of rice varieties that are resistant to Pb-induced oxidative stress is an important management strat... In rice,high concentration of lead(Pb)can cause phyto-toxicity affecting several physiological functions.Cultivation of rice varieties that are resistant to Pb-induced oxidative stress is an important management strategy in Pb-contaminated soils.In the current study,we evaluated four different rice cultivars for their response to Pb-induced stress.Three japonica type cultivars X-Jigna,Ediget,and Furat,and one Indica type cultivar Amber 33 were grown in soil containing different Pb concentrations(0 mM,0.6 mM,and 1.2 mM).The soil was treated with 0 mM or 0.6 mM or 1.2 mM Pb solution one month prior to rice seedling transplantation.Thereafter,four-week-old rice seedlings were transplanted into the treated soil and their responses were observed until maturity.The data revealed that a highest concentration of Pb(1.2 mM)induced significant reduction in agronomic traits such as plant height,number of tillers per plant,number of panicles per plant,and number of spikelets per panicle in all the rice cultivars.However,least reduction in the agronomic traits was observed in X-Jigna,whereas the highest reduction in the agronomic traits was observed in Ediget.Antioxidant activity of catalase(CAT),peroxidase(POD),polyphenol oxidase(PPO),and superoxide dismutase(SOD),was evaluated along with the accumulation of superoxide ions(O2.-),protein,proline,chlorophyll,sucrose,glucose,and fructose contents in all the rice cultivars.A significant increase in antioxidant activity and in the accumulation of proline and sucrose contents with the least reduction in the chlorophyll and protein contents was observed in X-Jigna suggesting that X-Jigna is the most tolerant among all the rice cultivars tested against Pb-stress.On the other hand,non-significant and slightly significant increase in the antioxidant activity,less accumulation of proline and sucrose contents,and higher reduction in the chlorophyll and protein contents was observed in Ediget,which further suggest that Ediget is the most susceptible rice cultivar to Pb-stress.In addition,the other rice cultivars Furat and Amber 33,were found to be moderately tolerant to Pb-induced oxidative stress.In summary,our results suggest that tolerance to Pb-induced oxidative stress would be a result of a synergetic action of both enzymatic and non-enzymatic antioxidant systems,leading to a balanced redox status in rice. 展开更多
关键词 lead(pb)toxicity Oxidative stress Morphological and physio-biochemical properties of rice
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Lead isotope geochemical characteristics of Pb-Zn-Cu deposits on the southwestern margin of Tarim,and their significance 被引量:3
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作者 SHEN Nengping ZHANG Zhengwei +3 位作者 YOU Fuhua PENG Jiantang ZHU Xiaoqing XIAO Jiafei 《Chinese Journal Of Geochemistry》 EI CAS 2012年第4期362-375,共14页
The polymetallic(Pb,Zn,Cu,etc) ore belt on the southwestern margin of Tarim is one of the major regions with the greatest prospecting potential in Xinjiang.Reported in this paper are the lead isotope data for 66 sulfi... The polymetallic(Pb,Zn,Cu,etc) ore belt on the southwestern margin of Tarim is one of the major regions with the greatest prospecting potential in Xinjiang.Reported in this paper are the lead isotope data for 66 sulfide samples(including 50 galena samples,15 chalcopyrite samples and 1 pyrite sample) collected from such representative deposits as Tamu,Tiekelike,Kalangu,Abalieke,etc.in this ore belt.The Pb isotopic ratios of 206 Pb/204 Pb,207 Pb/204 Pb and 208 Pb/204 Pb in the galena samples range from 17.931 to 18.176,15.609 to 15.818 and 38.197 to 38.944,with the average values of 18.017,15.684 and 38.462,respectively.Those in the chalcopyrite samples range from 17.926 to 18.144,15.598 to 15.628 and 38.171 to 38.583,with the average values of 18.020,15.606 and 38.262,respectively.The pyrite sample has the Pb isotopic ratios of 206 Pb/204 Pb,207 Pb/204 Pb and 208 Pb/204 Pb to be 17.980,15.604 and 38.145,respectively.In combination with the previous Pb isotope data for sulfides,it is found that there is only a slight variation in the Pb isotopic composition of galena,chalcopyrite,sphalerite and pyrite in the ore belt.However,there is some difference in Pb isotopic characteristics between galena and chalcopyrite,especially the Pb isotopic composition of galena shows an obvious linear correlation with some other relevant parameters(e.g.β and γ).The comprehensive analysis suggested that lead in galena(maybe including sphalerite and pyrite) was derived principally from wall rocks and underlying basement,and that in chalcopyrite only originated from the basement.The single-stage model ages of these sulfides couldn't indicate the time limit of metallogenesis(Pb,Zn,Cu,etc.),and the positive linear correlations for the Pb isotopic composition of galena are of no single-stage and two-stage Pb-Pb isochron significance.Furthermore,there are significant differences in Pb isotopic composition characteristics between the genetic type of deposits in this polymetallic ore belt and the Mississippi Valley type(MVT).In addition,the authors also pointed out that there is a phenomenon of differentiation(not paragenesis) for lead and copper elements during the process of metallogenesis in this ore belt. 展开更多
关键词 同位素地球化学特征 塔里木盆地 方铅矿 闪锌矿 铜沉积 南缘 多金属成矿带 铅同位素比值
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Lead Isotopic Composition and Lead Source of the Huogeqi Cu-Pb-Zn Deposit,Inner Mongolia,China 被引量:5
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作者 ZHU Xiaoqing ZHANG Qian +1 位作者 HE Yuliang ZHU Chaohui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第4期528-539,共12页
The Huogeqi orefield located on the northern side of Mt. Langshan, Inner Mongolia occurs in the Middle Proterozoic Langshan Group metamorphic rocks, and the orebodies arc stratiform. In the past twenty years, many Chi... The Huogeqi orefield located on the northern side of Mt. Langshan, Inner Mongolia occurs in the Middle Proterozoic Langshan Group metamorphic rocks, and the orebodies arc stratiform. In the past twenty years, many Chinese geologists have conducted researches on the Huogeqi Cu-Pb-Zn deposit, but there has been still a controversy on its origin. Some advocate that the deposit is of sedimentary-metamorphic rcworking origin, some hold that it is of sea-floor SEDEX origin, and others have a preference for magmatic superimposition origin. The crux of the controversy is that there is no common understanding about the source of ore-forming materials. In this paper, the Pb isotopic compositions of regional Achaean-Early Proterozoic basement rocks, various types of sedimentary- metamorphic rocks and volcanic rocks in the mining district, Late Proterozoic and Hercynian magmatic rocks arc introduced and compared with the orc-lead composition, so as to constrain the source of the ore lead. The result indicates that (1) sulfides in the ores have homogeneous Pb isotopic compositions, showing a narrow variation range. Their ^206pb/^204pb ratios arc within a range of 17.027- 17.317; ^207Pb/^204pb ratios, 15.451-15.786 and ^208Pb/^204pb ratios, 36.747-37.669; (2) the Pb isotopic compositions of the regional Achaean-Early Proterozoic basement rocks arc characteristic of the old Pb isotopic composition at the early-stage evolution of the Earth, which varies over a wider range, reflecting significant differences in Pb isotopic compositions of the ores. All this indicates that the source of ore lead has no bearing on the basement rocks; (3) the sedimentary-metamorphic rocks in the mining district arc characterized by highly variable and more radiogenic Pb isotopic compositions and their Pb isotopic ratios arc obviously higher than those of ores, demonstrating that ore lead did not result from metamorphic rcworking of these rocks; (4) Pb isotopic compositions of Late Proterozoic diorite-gabbro and Hercynian granite are higher than those of ores. Meanwhile, the Pb isotopic compositions of sulfides in the small-sized strata-penetrating mineralized veinlets formed at later stages arc completely consistent with that of sulfides in stratiform-banded ores, suggesting that these veiniets arc the product of autochthonous rcworking of the stratiform-banded ores during the period of metamorphism and the late magmatic superimposition-mineralization can be excluded; (5) amphibolite, whose protolith is basic volcanic rocks, has the same Pb isotopic compositions as ores, implying that ore lead was derived probably from basic volcanism. So, the source of ore-forming materials for the Huogeqi deposit is like that of the volcanic massive sulfide (VMS) deposits. However, the orebodies do not occur directly within the volcanic rocks, and instead they overlie the volcanic rocks, showing some differences from those typical VMS-type deposits. 展开更多
关键词 pb isotopic composition ore lead source Huogeqi Cu-pb-Zn deposit Inner Mongolia
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Residual Regularity in Tissues of Layer after Combined Exposure to Lead(Pb)and Cadmium(Cd)
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作者 Chen Dawei Liu Yinyin +5 位作者 Wang Qianqian Pu Junhua Ma Lina Ge Qinglian Tang Xiujun Gao Yushi 《Animal Husbandry and Feed Science》 CAS 2016年第5期255-256,263,共3页
[ Objective] The study was to investigate residual regularity in tissues of layer after combined exposure to lead (Pb) and/or cadmium ( Cd ). [ Method] I.aad acetate (100 mg/L) and/or cadmium chloride (50 mg/L... [ Objective] The study was to investigate residual regularity in tissues of layer after combined exposure to lead (Pb) and/or cadmium ( Cd ). [ Method] I.aad acetate (100 mg/L) and/or cadmium chloride (50 mg/L) were administered in drinking water to 120 individuals of 40 -week -old hyline layers for 8 weeks. [ Result] Compared with the Cd group, the Cd content in various tissues, except kidney and femur, in Cd + Pb group all increased, but the difference was not significant (P 〉 0.05 ). The Cd contents in kidney and femur in Cd group were significantly higher than that in Cd + Pb group. Compared with the group Pb, the Pb contents in breast muscle and kidney in Cd + Pb group decreased significantly ( P 〈 0.05 ) ; the Pb contents in femur decreased extremely ( P 〈 0.01 ) ; while the Pb contents in leg muscle, heart and spleen increased significantly ( P 〈 0.05 ) ; the Pb contents in liver and glandular stomach were almost the same. Compared with the control group, the Cd content in various tissues in Pb group increased significantly ( P 〈 0.05 ) ; no significant changes were observed for Pb content in Cd group. [ Conclusion] Deposit of Pb and Cd in poultry body had complex interaction. 展开更多
关键词 lead pb Cadmium (Cd) LAYER Residue
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Biosorptive Removal of Lead Ions from Aqeuous Stream by Using Leaves, Stems and Roots of Momordica charantia Biomass
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作者 Badar Khan Afifah Jabeen Khan 《Journal of Geoscience and Environment Protection》 2023年第12期28-57,共30页
Water pollution is one of the most important issues of the 21<sup>st</sup> century. It takes place when the pollutants are being entered into a water reservoir without any treatment. Heavy metals are one o... Water pollution is one of the most important issues of the 21<sup>st</sup> century. It takes place when the pollutants are being entered into a water reservoir without any treatment. Heavy metals are one of the major harmful pollutants that exist in the water;therefore, it is necessary to remove these toxic metals to keep our environment safe. Biosorption is an ecofriendly and economical technique for the elimination of these toxic metals from polluted water. In this research work roots, stems, and leaves of Momordica charantia (Bitter gourd) were used as biosorbent for the elimination of Pb (II) ions from aqueous solution. Many different parameters such as metal ion solution pH, biomass dosage, initial metal ions concentration and contact time were optimized in the batch experiments. The calculated results revealed that biosorption of Pb (II) was maximum at solution pH 5, biosorbent dosage of 0.1 g and 100 ppm of initial metal ions concentration within 240 minutes of contact time. M. charantia’s leaves showed the highest level of lead biosorption capacity (47.62%), followed by stems (42.36%) and roots (38.47%). The Freundlich isotherm and pseudo-second order kinetics model fitted well for the analytical data. The results indicated that Momordica charantia is an effective biosorbent for Pb (II) ions elimination from wastewater. 展开更多
关键词 BIOSORPTION lead (pb) Heavy Metal Environment Protection Wastewater Treatment Momordica charantia Biomass
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LA-ICP-MS U-Pb定年技术相关问题探讨 被引量:13
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作者 李艳广 靳梦琪 +1 位作者 汪双双 吕鹏瑞 《西北地质》 CAS CSCD 北大核心 2023年第4期274-282,共9页
LA-ICP-MS U-Pb定年技术是地质科学中被广泛应用的重要手段。发展至今,该技术已相对成熟,但在实际工作中仍需要注意一些关键问题。笔者就该技术的样品准备、定年结果的取舍、铅丢失问题、普通铅问题和定年结果投图与解释等5个方面进行... LA-ICP-MS U-Pb定年技术是地质科学中被广泛应用的重要手段。发展至今,该技术已相对成熟,但在实际工作中仍需要注意一些关键问题。笔者就该技术的样品准备、定年结果的取舍、铅丢失问题、普通铅问题和定年结果投图与解释等5个方面进行简要探讨。研究认为,对于复杂矿物进行U-Pb定年研究建议不分选出单矿物,而是采用矿物识别定位手段和LA-ICP-MS仪器相结合的技术手段,直接在岩石光片或探针片上进行原地原位微区定年分析,但要注意样品准备过程中可能存在的铅污染问题。在碎屑矿物定年结果选择方面,对于大于1.5Ga的定年测点,笔者建议采用207Pb/206Pb年龄代表该颗粒的结晶年龄,而对于小于1.5 Ga的定年测点则应采用206Pb/238U年龄。对沉积岩最大沉积年龄的判断和选择主要依靠统计学方法,必要时需要结合地球化学数据和地质背景信息作为辅助判断依据。对于连续分布在谐和线上的年轻样品要提高警惕,需要采用谐和图、加权平均图、CL图像和元素含量等多种手段识别是否存在铅丢失不一致线。针对普通铅校正问题,笔者重点介绍了一种专用于碎屑矿物U-Pb定年的普通铅校正方法,并给出了计算过程。关于对矿物U-Pb定年结果加权平均值数据质量的评价,笔者着重讨论MSWD越接近于1表示数据质量越高的理论基础。总之,应用LA-ICP-MS技术对矿物进行U-Pb定年研究需要综合考虑多个因素,才能得出准确、可靠和地质意义明确的定年结果。 展开更多
关键词 LA-ICP-MS U-pb定年 最大沉积年龄 铅丢失 普通铅 MSWD
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微波消解-石墨炉原子吸收法测定复杂油脂样品中铅(Pb)含量
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作者 范宁伟 郝俊凯 +1 位作者 秦慧芳 翦英红 《吉林化工学院学报》 CAS 2023年第11期15-19,共5页
针对混合油脂成分较多、杂质干扰大的特点,新建了微波消解-石墨炉原子吸收光谱法测定混合型复杂油脂样品中铅(Pb)含量的方法。通过对石墨炉条件进行优化,获得其最佳条件:基体改进剂体系为3μL磷酸二氢铵(1%)/硝酸镁(0.05%)混合溶液,灰... 针对混合油脂成分较多、杂质干扰大的特点,新建了微波消解-石墨炉原子吸收光谱法测定混合型复杂油脂样品中铅(Pb)含量的方法。通过对石墨炉条件进行优化,获得其最佳条件:基体改进剂体系为3μL磷酸二氢铵(1%)/硝酸镁(0.05%)混合溶液,灰化温度550℃,原子化温度1700℃。方法性能考察结果:在0~80μg/L范围内,所建方法的线性方程为y=0.0028x-0.0002,相关系数r^(2)=0.9979,加标回收率范围为95.5%~103.4%,RSD%范围为0.31%~2.13%(n=5),表明方法的线性良好,具有较高的准确度和精密度。采用所建方法测定了8种油脂样品中Pb的含量,测定结果表明:所建方法可以准确测定复杂油脂样品中Pb元素的含量。 展开更多
关键词 微波消解 石墨炉原子吸收光谱 复杂油脂样品 铅(pb)
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Sedum alfredii : A New Lead-Accumulating Ecotype 被引量:24
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作者 何冰 杨肖娥 +3 位作者 倪吾钟 魏幼璋 龙新宪 叶正钱 《Acta Botanica Sinica》 CSCD 2002年第11期1365-1370,共6页
hi a survey of plant population, Sedum alfredii Hance, a new lead (Pb)-tolerant and lead (Pb)accumulating ecotype, was found in an old Pb/Zn mining area in Zhejiang Province of China. The growth and Pb content of plan... hi a survey of plant population, Sedum alfredii Hance, a new lead (Pb)-tolerant and lead (Pb)accumulating ecotype, was found in an old Pb/Zn mining area in Zhejiang Province of China. The growth and Pb content of plant ecotypes being able to and unable to accumulate Pb were studied by hydroponic culture with different concentrations of Pb(NO3)(2). Growth of shoots of accumulating ecotype was not affected by Ph treatments up to 320 mg/L, whereas that of non-accumulating ecotype was inhibited in all Ph treatments. The Ph concentrations in the roots and shoots of accumulating ecotype increased with increasing of Pb level in the nutrient solution. The maximum Ph concentrations in the shoots and roots of accumulating ecotype were 514 mg/kg and 13 922 mg/kg, 2.27 times and 2.62 times as much as that of non-accumulating ecotype, respectively. The highest rate of Pb accumulation of accumulating ecotype was 8.62 mug/plant/d, 7.16 times as much as that of non-accumulating ecotype. Due to its fast growth rate and high Pb-accumulating ability, from a phytoremediation perspective, accumulating ecotype of S. alfredii is a potential plant species for Pb removal from contaminated soils. 展开更多
关键词 lead (pb) POLLUTION Sedum alfredii
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广西刁江沿岸土壤As,Pb和Zn污染的分布规律差异 被引量:20
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作者 刘永轩 黄泽春 +2 位作者 蹇丽 杨子良 张增强 《环境科学研究》 EI CAS CSCD 北大核心 2010年第4期485-490,共6页
分析了刁江流域矿区尾砂和上、中、下游地区土壤剖面重金属的含量.结果表明:刁江流域上、中、下游地区都不同程度受到As,Pb和Zn的污染.上游(距污染源16 km)表层土壤中w(As),w(Pb)和w(Zn)与尾砂相当,分别高达2.4×104,5.6×103和... 分析了刁江流域矿区尾砂和上、中、下游地区土壤剖面重金属的含量.结果表明:刁江流域上、中、下游地区都不同程度受到As,Pb和Zn的污染.上游(距污染源16 km)表层土壤中w(As),w(Pb)和w(Zn)与尾砂相当,分别高达2.4×104,5.6×103和1.2×104mg/kg,下游拉烈和百旺(分别距污染源154和192 km)2个采样点表层土壤中w(As),w(Pb)和w(Zn)的平均值分别是《土壤环境质量标准》(GB15618—1995)三级标准的47.05,1.81和5.48倍.表层土壤中w(As)和w(Pb)随采样点距污染源的距离增加呈幂函数下降,w(Zn)呈线性下降,表明Zn在流域内的迁移能力大于Pb和As.土壤剖面中3种重金属的质量分数均随土层深度的增加呈降低趋势,在土壤剖面的迁移能力表现为Zn>Pb>As.总体上看,刁江流域土壤污染与尾砂中重金属的形态及其迁移特征密切相关,尾砂的排放控制和治理应该是刁江流域污染整治的关键. 展开更多
关键词 AS pb ZN 尾砂 刁江
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Pb污染对马蔺生长、体内重金属元素积累以及叶绿体超微结构的影响 被引量:22
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作者 原海燕 郭智 黄苏珍 《生态学报》 CAS CSCD 北大核心 2011年第12期3350-3357,共8页
通过土壤单因子Pb胁迫盆栽试验和铅锌尾矿污染土壤掺比试验研究了不同土培条件下Pb对马蔺(Iris lacteavarchinensis)生长、体内重金属元素积累以及叶绿体超微结构的影响。结果表明:2种不同土壤Pb胁迫下马蔺株高、根长、叶数以及地上、... 通过土壤单因子Pb胁迫盆栽试验和铅锌尾矿污染土壤掺比试验研究了不同土培条件下Pb对马蔺(Iris lacteavarchinensis)生长、体内重金属元素积累以及叶绿体超微结构的影响。结果表明:2种不同土壤Pb胁迫下马蔺株高、根长、叶数以及地上、地下部生物量均随Pb浓度的增加呈先增后降的趋势,其中,土壤单Pb胁迫下,低于500 mg/kg Pb胁迫(T1—T3)均增加了马蔺的株高和根长,仅800mg/kg高Pb浓度处理时马蔺生物量才出现轻微下降(P>0.05);与单一土壤Pb胁迫相比,铅锌尾矿污染土壤掺比试验中铅锌尾矿含量低于一定浓度下对马蔺株高、根长生长同样也具有促进效应,只有100%尾矿污染土壤处理下马蔺地上部和根系生物量下降显著(P<0.05)。马蔺地上部和根系Pb含量均随土壤中Pb浓度和尾矿含量的增加而增加,800mg/kg土壤单Pb胁迫下为340.6、1700.02 mg/kg,100%尾矿污染土壤处理下为126.9、1725 mg/kg。Pb单独胁迫下马蔺地上部Zn含量随Pb含量的增加逐渐下降,Zn和Pb的吸收表现出一定的拮抗效应;而不同掺比污染土壤胁迫下马蔺地上部和根系Zn积累同Pb一样,均随土壤中Pb、Zn浓度的增加而增加,Zn和Pb的吸收表现为一种协同效应。而2种不同土壤Pb胁迫下马蔺对Cu、Cd的吸收均相对较少。研究中,800mg/kg Pb胁迫处理和50%尾砂土壤胁迫处理下马蔺叶片叶绿体双层被膜及内部基粒和类囊体结构与对照相比变化不大。综上表明,马蔺对重金属Pb有较强的耐受性,具备修复Pb污染土壤的潜在能力。 展开更多
关键词 pb污染 马蔺 积累 叶绿体超微结构
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湘江入湖河段沉积物重金属污染及其Pb同位素地球化学示踪 被引量:75
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作者 彭渤 唐晓燕 +6 位作者 余昌训 谭长银 涂湘林 刘茜 杨克苏 肖敏 徐婧喆 《地质学报》 EI CAS CSCD 北大核心 2011年第2期282-299,共18页
湘江是我国重金属污染最严重的河流之一。本次工作利用等离子质谱(ICP-MS)和多接收同位素质谱(MC-ICP-MS)等技术,对湘江入湖河段沉积物进行了系统的重金属微量元素和Pb同位素分析。结果表明,湘江河床沉积物明显富集Bi、Sc、V、Mn、Ni、C... 湘江是我国重金属污染最严重的河流之一。本次工作利用等离子质谱(ICP-MS)和多接收同位素质谱(MC-ICP-MS)等技术,对湘江入湖河段沉积物进行了系统的重金属微量元素和Pb同位素分析。结果表明,湘江河床沉积物明显富集Bi、Sc、V、Mn、Ni、Cu、Zn、Pb、Cd、Sn、Sb等多种重金属微量元素,而湖盆沉积物重金属微量元素的富集程度明显降低。地累积指数(Igeo)评价显示,河床沉积物存在Cd、Sb、Bi、Sn、Pb、Zn、U、Tl、Th、Mn、Cu等重金属污染,其中Cd达严重污染程度,Sb、Bi、Sn、Pb等达到中度至重度污染程度,而Zn、U、Tl、Th、Mn、Cu等达中度或轻度污染程度。湖盆沉积物除存在中度的Cd、Sb污染外,其余多数重金属未达到污染水平。铅同位素示踪分析表明,河床沉积物的铅是来自流域上游花岗岩风化的自然源Pb,和流域上游Pb-Zn矿床的矿石铅与燃煤烟尘带入的铅等人为源Pb组成的多元混合铅。且河床沉积物中人为源Pb占80%的比例。湖盆沉积物中的铅则以人为源Pb为主,受上游岩石风化影响较小,为来自流域Pb-Zn矿床的矿石铅和燃煤烟尘带入的铅组成的二元混合铅。河床沉积物存在的Sc、Cd、Bi、Cu、Zn、Sn、Sb等重金属污染与Pb一样,为自然来源和人为来源重金属组成的多元混合重金属污染。 展开更多
关键词 重金属污染 铅同位素 人为源pb 自然源pb 沉积物 湘江
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模拟酸雨条件下改性沸石对污染土Pb、Zn的淋溶效应 被引量:7
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作者 陶权 姚景 +3 位作者 何树福 杨毅 李跃 梁英 《水土保持学报》 CSCD 北大核心 2015年第5期304-308,共5页
通过室内模拟土柱淋溶实验,研究了不同pH值(3.1,4.1,6.5)的酸雨下,改性沸石用于控制污染土重金属Pb、Zn的淋溶效果。结果表明,淋溶过程中,酸雨pH值越小,改性沸石剂量越高,淋滤液的pH值相对越大,且酸雨pH值的降低并没有引起Pb、Zn淋溶总... 通过室内模拟土柱淋溶实验,研究了不同pH值(3.1,4.1,6.5)的酸雨下,改性沸石用于控制污染土重金属Pb、Zn的淋溶效果。结果表明,淋溶过程中,酸雨pH值越小,改性沸石剂量越高,淋滤液的pH值相对越大,且酸雨pH值的降低并没有引起Pb、Zn淋溶总量的显著增加;不同pH和不同剂量改性沸石下,Pb的淋溶总量要明显大于Zn的淋溶总量;相比于空白剂量(0g/kg)沸石,高剂量(100g/kg)改性沸石和低剂量(20g/kg)改性沸石均能显著降低Pb和Zn的淋溶总量,且两者所起效果相差不大,其中,酸雨pH值为3.1,4.1和6.5时,对添加低剂量沸石,Pb的淋溶总量分别降低28.7%,34.8%和40%,而Zn的淋溶总量分别降低48.5%,53.9%和45.5%。研究结果表明,天然沸石经过一定方法改性后,可以有效防止酸雨条件下污染土壤重金属Pb和Zn的淋溶流失。 展开更多
关键词 土壤 沸石 酸雨 淋溶
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Pb胁迫对香豌豆幼苗部分生长和生理生化指标的影响 被引量:14
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作者 司卫静 原海燕 +1 位作者 韩玉林 许敏 《植物资源与环境学报》 CAS CSCD 北大核心 2013年第2期86-91,共6页
采用盆栽方法研究了土壤中0(CK)、150、300、450和600 mg.kg-1铅(Pb)对香豌豆(Lathyrus odoratus Linn.)幼苗部分生长和生理生化指标的影响。结果表明:随Pb质量浓度的提高,香豌豆株高、根长以及地上和地下部分的干质量均呈逐渐下降趋势... 采用盆栽方法研究了土壤中0(CK)、150、300、450和600 mg.kg-1铅(Pb)对香豌豆(Lathyrus odoratus Linn.)幼苗部分生长和生理生化指标的影响。结果表明:随Pb质量浓度的提高,香豌豆株高、根长以及地上和地下部分的干质量均呈逐渐下降趋势,耐性指数呈低质量浓度条件下升高、高质量浓度条件下降低的趋势;其中,在450和600 mg.kg-1Pb胁迫条件下,香豌豆幼苗根长以及地上部分和地下部分的干质量均显著低于对照(P<0.05),说明植株的生长受到明显抑制。随Pb质量浓度的提高,幼苗地上和地下部分的相对电导率和SOD活性呈逐渐增加的趋势,其中,在600 mg.kg-1Pb胁迫条件下相对电导率和SOD活性均最高。各处理组地上和地下部分的脯氨酸(Pro)含量呈低质量浓度条件下降低、高质量浓度条件下增加的趋势,而POD活性、谷胱甘肽(GSH)和抗坏血酸(AsA)含量则呈现低质量浓度条件下增加、高质量浓度条件下降低的趋势。其中,在300 mg.kg-1Pb胁迫条件下Pro含量最低且显著低于对照;在450 mg.kg-1Pb胁迫条件下POD活性最高;在150 mg.kg-1Pb胁迫条下GSH含量最高,且各处理组间POD活性和GSH含量有显著差异;但各处理组AsA含量均与对照无显著差异。研究结果表明:香豌豆对Pb胁迫具有一定的耐性,可用于轻度Pb污染环境的修复。 展开更多
关键词 香豌豆 铅(pb)胁迫 生长指标 生理生化指标
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