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Exploration and Sources of Bauxite Deposit in the Boloven Plateau, Southern Laos

Journal of Earth Science 2019年第1期30卷 121-130页

作者： yongzhen long Xiaoyong Yang Mu Yang Dexian Zhang Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationCentral South University School of Geosciences and Info-Physics Central South University CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of China

The Boloven bauxite deposit occurs either in the weathered basalt(alkali basalt and tholeiite), or in the Cretaceous sandstone. It is generally agreed that the bauxite deposits/laterites overlying the alkali basalt and tholeiite were derived from weathering of underlying basalt, however, the origin of bauxite deposit overlying the sandstone remains controversial. Chondrite-normalized REE patterns show that the bauxite ores/laterites overlying the sandstone exhibit quite similar chondrite-normalized REE patterns to those overlying the alkali basalt. Diagram of Al-Ti-Zr shows that the bauxite ores/laterites overlying the sandstone, tholeiite and alkali basalt are close to each other and to the calc-alkaline suite, however, significantly different from the sandstone and shales. Binary diagram of log Nb/Y vs log Zr/Ti further indicates that the parent rocks of bauxite ores/laterites overlying the sandstone belong to the suit of ultra-alkali to alkali basalt. Multivariate statistical analysis of geochemical data exhibit that the geochemical characteristics of HREE, Y, LREE and Al_2O_3 for bauxite ores/laterites overlying the sandstone are similar to those overlying the alkali basalt(15.7 Ma), obviously different from those overlying the tholeiite(1.2 to 0.5 Ma). Consequently, it can be inferred that the bauxite deposits/laterites overlying the sandstone were derived from the alkali basalt.

关键词： late ritic-type bauxite XRD datum processing exploration sources Boloven Plateau Laos

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Sources of Polycyclic Aromatic Hydrocarbons in Street Dust from the Chang-Zhu-Tan Region, Hunan, China

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Journal of Environmental Protection 2011年第10期2卷 1331-1340页

作者： yongzhen long Guoxiang Chi Hairuo Qing Tagen Dai Qianhong Wu 不详

Street dusts collected from 20 sites as well as three special dust samples collected from chimney of coal-fired plant, smelter and refinery of nonferrous metals and automobile exhaust, respectively, in the Chang-Zhu-Tan (Changsha, Zhuzhou and Xiangtan) urban region, Hunan, China, in May to August 2009, were investigated for sources of polycylic aromatic hydrocarbons (PAHs). The ΣPAHs16 levels were in the range of 3515 - 24488 ng/g, with a mean of 8760 ng/g. The sources of PAH inputs to street dusts were determined by isomer ratios, principal components analysis and REE geochemical analysis. The isomer ratios suggested a rather uniform mixture of coal combustion and petroleum PAH sources. Factor analysis indicated that the main sources of 16 PAHs were coal combustion/vehicle exhaust and coking/ petroleum. Rare earth elements (REE) and Factor score analysis further indicated the possible dust sources were from background soil, coal or coking combustion, nonferrous metal factories, traffic exhaust.

关键词： Street Dust Polycclic Aromatic Hydrocarbons Rare Earth Element Sources of Pollution

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Enrichment of anammox biomass during mainstream wastewater treatment driven by achievement of partial denitrification through the addition of bio-carriers

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Journal of Environmental Sciences 2024年第3期137卷 181-194页

作者： Yuqing Ma Bo Wang Xiaodi Li Shuo Wang Wen Wang yongzhen Peng National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology Engineering Research Center of BeijingBeijing University of TechnologyBeijing 100124China

Anammox is widely considered as the most cost-effective and sustainable process for nitrogen removal.However,how to achieve the enrichment of anammox biomass remains a challenge for its large-scale application,especially in mainstream wastewater treatment.In this study,the feasibility of enrichment of anammox biomass was explored through the realization of partial denitrification and the addition of bio-carriers.By using ordinary activated sludge,a sequencing batch reactor(SBR)followed by an up-fow anaerobic sludge bed(UASB)was operated at 25±2℃ for 214 days.The long-term operation was divided into five phases,in which SBR and UASB were started-up in Phases I and II,respectively.By eliminating oxygen and adjusting the infow ratios in Phases III-V,advanced nitrogen removal was achieved with the effuent total nitrogen being 4.7 mg/L and the nitrogen removal efficiency being 90.5%in Phase V.Both in-situ and ex-situ activity tests demonstrated the occurrence of partial denitrification and anammox.Moreover,16S rRNA high-throughput sequencing analysis revealed that Candidatus Brocadia was enriched from below the detection limit to in biofilms(0.4%in SBR,2.2%in UASB)and the foc sludge(0.2%in SBR,1.3%in UASB),while Thauera was mainly detected in the foc sludge(8.1%in SBR,8.8%in UASB),which might play a key role in partial denitrification.Overall,this study provides a novel strategy to enrich anammox biomass driven by rapid achievement of partial denitrification through the addition of bio-carriers,which will improve large-scale application of anammox processes in mainstream wastewater treatment.

关键词： Enrichment Anammox biomass Bio-carriers Partial denitrification Mainstream wastewater

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Recent advances in solving Li_(2)CO_(3) problems in garnet-based solid-state battery: A systematic review(2020-2023)

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Journal of Energy Chemistry 2024年第3期90卷 58-76,I0004页

作者： Shaoxiong Han Ziqi Wang Yue Ma Yanlan Zhang yongzhen Wang Xiaomin Wang College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Shanxi Joint Laboratory of Coal based Solid Waste Resource Utilization and Green Ecological Development Taiyuan 030024ShanxiChina

Garnet solid electrolytes are one of the most promising electrolytes for solid-state batteries.However,Li_(2)CO_(3) is a critical issue that hinders the practical application of garnet-based solid-state lithium-ion batteries.There are two sources of Li_(2)CO_(3) contamination.The main one is the aging of garnet electrolytes in the *** electrolytes can react with H_(2)O and CO_(2) in the air to form Li_(2)CO_(3),which reduces ion conductivity,increases electrode/garnet electrolyte interface resistance,and deteriorates the electrochemical performance of the battery.Various strategies,such as elemental doping,grain boundary manipulation,and interface engineering,have been suggested to address these issues.The other is the passivation layer(Li_(2)CO_(3),Li_3N,LiOH,Li_(2)O) formed on the surface of the lithium foil after long-term storage,which is ignored by most researchers.To better understand the current strategies and future trends to address the Li_(2)CO_(3) problem,this perspective provides a systematic review of journals published in this field from 2020-2023.

关键词： Solid-state batteries Garnet electrolytes Air stability Interface engineering Lithium foil contamination

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贵州云峰铝土矿中铀矿物的发现

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矿床地质 2019年第1期38卷 170-180页

作者：龙永珍池国祥谷湘平戴塔根中南大学有色金属成矿预测与地质环境监测教育部重点实验室湖南长沙410083 中南大学地球科学与信息物理学院湖南长沙410083 Department of Geology University of Regina

有关铝土矿中铀富集的报道很多,但至今未见独立铀矿物存在的相关文献。本次研究采用岩相学观察、X衍射(XRD)、ICP-MS、电子探针(EPMA)、拉曼光谱分析等手段,对黔中典型的铝土矿——云峰铝土矿中的晶质铀矿进行了研究。研究发现该铝土矿... 详细信息

有关铝土矿中铀富集的报道很多,但至今未见独立铀矿物存在的相关文献。本次研究采用岩相学观察、X衍射(XRD)、ICP-MS、电子探针(EPMA)、拉曼光谱分析等手段,对黔中典型的铝土矿——云峰铝土矿中的晶质铀矿进行了研究。研究发现该铝土矿床中,铀富集明显(w(U)(18×10^(-6)～62×10^(-6)),平均值35×10^(-6)),铀矿物大小呈微米至亚微米级,围绕锐钛矿边缘生长、或充填于高岭石微裂隙中、或散布于与黄铁矿密切相关的高岭石或硬水铝石中。铀矿物的主要组分为UO_2(w(UO_2)为52.2%～80.88%)和TiO_2(w(TiO_2)为1.85%～14.98%);电子探针面扫描显示铀矿物中钛分布不均匀;铀矿物的拉曼特征波长为442 cm^(-1)和454 cm^(-1),因此,初步推测铀矿物为晶质铀矿和含钛晶质铀矿。其形成过程大致如下,来源于下寒武统牛蹄塘组黑色岩系中的铀(U^(4+))在风化过程中氧化为U^(6+)、析出、被Al^-, Fe^-氧化物/氢氧化物吸附;在沉积和成岩过程中,随着三水铝石转变为勃姆石和硬水铝石、铁氧化/氢氧化物转变为黄铁矿,吸附的铀解吸、还原(U^(6+)至U^(4+))、最后形成铀矿物。

关键词：地球化学铀矿物铝土矿电子探针拉曼光谱云峰贵州

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亚抑制浓度庆大霉素通过抑制ATP的产生降低大肠杆菌丛动能力的机制

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实用医学杂志 2022年第3期38卷 306-310页

作者：祝晓娟龙永珍陈晓玲张莹彭青周树勤喀什地区第一人民医院麻醉科新疆喀什844000 南方医科大学珠江医院再生医学研究所广州510280 广州市红十字会医院儿科广州510220 南方医科大学珠江医院麻醉科广州510280

目的前期研究发现,大肠杆菌经亚抑制浓度的庆大霉素预处理后,丛动性可显著降低,本研究将基于前期的工作基础,探讨亚抑制浓度的庆大霉素对大肠杆菌丛动性的抑制作用的相关机制。方法确认亚抑制浓度庆大霉素预处理对大肠杆菌ATCC25922丛... 详细信息

目的前期研究发现,大肠杆菌经亚抑制浓度的庆大霉素预处理后,丛动性可显著降低,本研究将基于前期的工作基础,探讨亚抑制浓度的庆大霉素对大肠杆菌丛动性的抑制作用的相关机制。方法确认亚抑制浓度庆大霉素预处理对大肠杆菌ATCC25922丛动性的抑制作用,Real-timePCR测定庆大霉素对三羧酸循环(TCA)相关基因的表达水平的影响,ATP检测试剂盒检测庆大霉素对ATP产生的影响,并观察在丛动平板中补充ATP对庆大霉素预处理大肠杆菌丛动性的逆转作用。结果1/2 MIC庆大霉素预处理可显著抑制大肠杆菌ATCC25922的丛动能力,Real-time PCR结果提示经庆大霉素处理的大肠杆菌TCA相关基因,poxB、aceE、gltA、sdhD、sdhC、sucC、fumA及icd基因表达均下调,细菌ATP产生减少,在丛动平板中补充ATP可逆转庆大霉素对大肠杆菌丛动性的抑制作用。结论亚抑制浓度庆大霉素可通过下调TCA相关基因,减少细菌ATP的产生,抑制大肠杆菌的丛动能力。该结果为进一步揭示庆大霉素的抗生素后效应发生机制提供了新的理论依据。

关键词：庆大霉素大肠杆菌丛动三羧酸循环 ATP

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水循环荷载作用下高面板堆石坝长期变形特性研究

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岩土工程学报 2024年第6期46卷 1339-1346页

作者：杨启贵王艳丽左永振长江设计集团有限公司湖北武汉430010 长江科学院水利部岩土力学与工程重点实验室湖北武汉430010

高面板堆石坝的长期变形是面板坝建设中的关键技术问题之一,已有研究大多将长期变形归结为堆石体蠕变的结果,但某些高面板堆石坝的变形原型监测资料显示,仅从堆石体蠕变角度难以解释高面板堆石坝长期变形的机理。通过水布垭面板堆石坝17... 详细信息

高面板堆石坝的长期变形是面板坝建设中的关键技术问题之一,已有研究大多将长期变形归结为堆石体蠕变的结果,但某些高面板堆石坝的变形原型监测资料显示,仅从堆石体蠕变角度难以解释高面板堆石坝长期变形的机理。通过水布垭面板堆石坝17a的变形监测资料分析和室内低频循环荷载作用下堆石料变形特性试验,探讨了实际运行中库水位周期性变化形成的循环荷载对高面板堆石坝长期变形特性的影响。结果表明:(1)坝体填筑和初次蓄水引起堆石体的瞬时变形和蠕变,堆石体的后期变形主要是水循环荷载长期作用的结果。(2)水循环荷载作用下,堆石体的变形表现为两种形式,其一为不可恢复的永久变形(亦称为残余变形),其二为可恢复的弹性变形。(3)室内低频循环荷载作用试验得到的堆石料变形及其增长规律很好地验证了水循环荷载与堆石坝后期变形的相互关系以及后期变形的力学意义。研究成果为高面板堆石坝长期变形特性研究提供了新的思路,并为具有往复大消落特点的高面板堆石坝变形及安全控制提供借鉴。

关键词：水循环荷载面板堆石坝长期变形实测资料周期性小主应力低频

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Insights into the mechanism of the deterioration of mainstream partial nitritation/anammox under low residual ammonium

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Journal of Environmental Sciences 2023年第4期126卷 29-39页

作者： Yandong Yang Yiming Jiang Yanan long Jiarui Xu Changqing Liu Liang Zhang yongzhen Peng School of Environmental and Municipal Engineering Qingdao University of TechnologyQingdao 266033China National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery EngineeringBeijing University of TechnologyBeijing 100124China

Residual ammonium is a critical parameter affecting the stability of mainstream partial nitritation/anammox(PN/A), but the underlying mechanism remains unclear. In this study,mainstream PN/A was established and operated with progressively decreasing residual ammonium. PN/A deteriorated as the residual ammonium decreased to below 5 mg/L, and this was paralleled by a significant loss in anammox activity in situ and an increasing nitrite oxidation rate. Further analysis revealed that the low-ammonium condition directly decreased anammox activity in situ via two distinct mechanisms. First, anammox bacteria were located in the inner layer of the granular sludge, and thus were disadvantageous when competing for ammonium with ammonium-oxidizing bacteria(AOB) in the outer layer. Second, the complete ammonia oxidizer(comammox) was enriched at low residual ammonium concentrations because of its high ammonium affinity. Both AOB and comammox presented kinetic advantages over anammox bacteria. At high residual ammonium concentrations,nitrite-oxidizing bacteria(NOB) were effectively suppressed, even when their maximum activity was high due to competition for nitrite with anammox bacteria. At low residual ammonium concentrations, the decrease in anammox activity in situ led to an increase in nitrite availability for nitrite oxidation, facilitating the activation of NOB despite the dissolved oxygen limitation(0.15–0.35 mg/L) for NOB persisting throughout the operation. Therefore, the deterioration of mainstream PN/A at low residual ammonium was primarily triggered by a decline in anammox activity in situ. This study provides novel insights into the optimized design of mainstream PN/As in engineering applications.

关键词： Mainstream partial nitritation/anammox Residual ammonium Granular sludge Comammox

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湘东金管冲铀矿床地球化学特征及其成因分析

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矿产与地质 2016年第4期30卷 542-549页

作者：谢玉华龙永珍湖南省核工业地质局三〇一大队湖南长沙410114 中南大学有色金属成矿预测教育部重点实验室地球科学与信息物理学院湖南长沙410083

湘东金管冲铀矿床位于区域性NNE―NE主干断裂附近,主要赋存于丫江桥复式花岗岩岩体的内外接触带中。对矿区的岩体、岩脉、矿石进行主量、微量元素,硫、氢和氧稳定同位素分析,以及流体包体分析。研究表明:成矿物质主要来源于地幔,其次有... 详细信息

湘东金管冲铀矿床位于区域性NNE―NE主干断裂附近,主要赋存于丫江桥复式花岗岩岩体的内外接触带中。对矿区的岩体、岩脉、矿石进行主量、微量元素,硫、氢和氧稳定同位素分析,以及流体包体分析。研究表明:成矿物质主要来源于地幔,其次有部分源自岩体或地层;成矿流体富碱(Ca^(2+)、Na^+、K^+)和富挥发分(CO_2、H_2O)具有极强的渗透能力、萃取能力;铀沉淀于中—低温、弱碱偏中性、强还原的环境。铀矿的形成与定位与晚燕山期华南陆块拉张作用所形成的岩浆岩密切相关。

关键词：金管冲铀矿地球化学特征物质来源成因机制

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模拟酸雨对冶炼厂土壤中Cd释放行为影响的研究

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广东微量元素科学 2009年第5期16卷 39-46页

作者：龙永珍戴塔根吴堑虹中南大学地学与环境工程学院湖南长沙410083

模拟株洲地区降水酸度及离子组成,用pH 3.5、pH 4.5、pH 5.6的模拟酸雨对株洲冶炼厂土壤样品(S1)进行了Cd动态淋溶试验。结果表明,酸雨加速了土壤中Cd的释放,表现为模拟酸雨pH值越低Cd释放量越大;且在pH 3.5、pH 4.5的平均释放水平是对... 详细信息

模拟株洲地区降水酸度及离子组成,用pH 3.5、pH 4.5、pH 5.6的模拟酸雨对株洲冶炼厂土壤样品(S1)进行了Cd动态淋溶试验。结果表明,酸雨加速了土壤中Cd的释放,表现为模拟酸雨pH值越低Cd释放量越大;且在pH 3.5、pH 4.5的平均释放水平是对照组(pH 5.6)的3.97和2.94倍;其释放量与土壤中Cd的原始含量、赋存形态关系密切;淋出液中Cd与Zn呈显著的正相关关系,相关系数均大于0.94;与Pb呈负相关关系,冶炼厂Cd的来源应与工厂Zn的生产关系密切,在pH 3.5、pH 4.5的模拟酸雨作用下分别是国家饮用水源水质标准值的1 037倍、768倍。随着淋溶的进行,酸雨可加速工厂土壤中Cd的释放,对人类存在着直接或潜在的危害性。

关键词：酸雨冶炼厂土壤 Cd 释放行为

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