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The effect of extracellular polymeric substances (EPS) of iron-oxidizing bacteria (Ochrobactrum EEELCW01) on mineral transformation and arsenic (As) fate

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Journal of Environmental Sciences 2023年第8期130卷 187-196页

作者： Chuan Wu Yueru chen Ziyan Qian hongren chen Waichin Li Qihou Li Shengguo Xue School of Metallurgy and Environment Central South UniversityChangsha 410083China Department of Science and Environmental Studies The Education University of Hong KongHong Kong 999077China Ministry of Scientific Research Central South UniversityChangsha 410083China

Extracellular polymeric substances(EPS)are an importantmedium for communication and material exchange between iron-oxidizing bacteria and the external environment and could induce the iron(oxyhydr)oxides production which reduced arsenic(As)*** main component of EPS secreted by iron-oxidizing bacteria(Ochrobactrum EEELCW01)was composed of polysaccharides(150.76-165.33 mg/g DW)followed by considerably smaller amounts of proteins(12.98–16.12 mg/g DW).Low concentrations of As(100 or 500μmol/L)promoted the amount of EPS *** results showed that EPS was composed of polysaccharides,proteins,and a miniscule amount of nucleic *** functional groups including-COOH,-OH,-NH,-C=O,and-C-O played an important role in the adsorption of *** results showed that As was bound to EPS in the form of As3+.With increasing As concentration,the proportion of As3+adsorbed on EPS *** with a weak crystalline state was only produced in the system at 6 hr during the mineralization process of Ochrobactrum *** day 8,the minerals were composed of goethite,galena,and *** the increasing mineralization time,the main mineral phases were transformed from weakly crystalline hydrous iron ore into higher crystallinity siderite(FeCO_(3))or goethite(α-FeOOH),and the specific surface area and active sites of minerals were *** can be seen from the distribution of As elements that As is preferentially adsorbed on the edges of iron *** study is potential to understand the biomineralizationmechanism of iron-oxidizing bacteria and As remediation in the environment.

关键词： Iron-oxidizing bacteria Extracellular polymeric substances (EPS) Arsenic(As) Biomineralization Mineral phases transformation

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Abrasion Resistance of Cement Paste with Granulated Blast Furnace Slag and Its Relations to Microhardness and Microstructure

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Journal of Wuhan University of Technology(Materials Science) 2022年第3期37卷 410-415页

作者： chen Xiaorun HE Zhen CAI Xinhua ZHAO Rixu HU Lingling chen hongren China West Construction Academy of Building Materials Chengdu 610015China China Construction Ready Mixed Concrete Co. Ltd.Wuhan 430205China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Shandong Chunhe New Material Research Institute Co. Ltd.Rizhao 276800China Hubei(Wuhan)Institute of Explosion Science and Blasting Technology Jianghan UniversityWuhan 430056China

The abrasion resistance of cement pastes with 30 wt%,40 wt%and 50 wt%granulated blast furnace slag(GBFS),and its relations to microhardness and microstructure like hydration products and pore structure were *** indicated that GBFS decreased the abrasion resistance of paste,and among the pastes with GBFS,the paste with 40 wt%GBFS showed the highest abrasion *** microhardness of GBFS was lower than that of the cement,and the microhardness of the hydration products in paste with GBFS was also lower than that of the hydration products in paste without GBFS,so that the abrasion resistance of paste decreased when GBFS was *** reason for the decrease of microhardness of pastes with GBFS was that the contents of Ca(OH)_(2)in pastes with GBFS was significantly lower than that in the paste without GBFS,while large amounts of calcium aluminate hydrates and hydrotalcite-like phases(HT)in pastes with GBFS were ***,among the pastes with GBFS,the paste with 40 wt%GBFS showed the lowest porosity which was the main reason for its highest abrasion resistance.

关键词： paste abrasion resistance granulated blast furnace slag microhardness microstructure

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Fluorocarbon and Hydrocarbon Benzodioxocycloalkane （C8-Cl0） End Groups： Effects on Mesomorphism

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Chinese Journal of Chemistry 2013年第7期31卷 933-938页

作者： Wanwan Cao Peilian Liu hongren chen Yaohang Zhu Rihao chen Qifang Zhou Zhuo Zeng College of Chemistry & Environment South China Normal University Guangzhou Guangdong 510006 China Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

A new class of benzodioxocycloalkane-based （C8-C10） liquid crystals were prepared. The impact of ring （C8- C10） as end group was investigated. The 8--9 membered ring derivatives, 3a--3b, exhibited the nematic phases （N） The mesomorphic behaviors were weakened with increasing the size of the ring. For the fluorinated medium ring （C8--C10） 3d--3f, it was found only the fluorinated ten membered ring 3f showed the LC phases behaviours. Modification of the ring size with different length alkyl groups and variation of the alkyl to polyfluoroalkyl markedly influenced the properties of these compounds.

关键词： fluorine heterocycles liquid crystals mesophases phase transitions

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Exploring a particle-size-reduction strategy of YAG:Ce phosphor via a chemical breakdown method

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Journal of Rare Earths 2021年第8期39卷 938-945页

作者： hongren chen Licheng Ju Li Zhang Xin Wang Linbo Zhang Xin Xu Lin Gao Kehui Qiu Liangjun Yin School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China College of Materials and Chemistry&Chemical Engineering Chengdu University of TechnologyChengdu 610059China Department of Materials Science and Engineering University of Central FloridaOrlando 32816USA National Engineering Research Center of Electromagnetic Radiation Control Materials University of Electronic Science and Technology of ChinaChengdu 6U731China Laboratory of Materials for Energy Conversion Department of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China CNBM(Hefei)Powder Technology Equipment CO. Ltd.Hefei Cement Research&Design InstituteHefei 230026China

Particle size reduction of Y_(3)Al_(5)O_(12):Ce(YAG:Ce) phosphor is highly needed for micro-LED display *** this work,size control of YAG:Ce phosphor particles is achieved via carbon coating and further heat treatment.A thin layer of carbon is deposited on the surface of YAG:Ce by chemical vapor *** the heat treatment,carbon reacts with oxygen element in the phosphor and escapes from phosphor *** reaction results in the phosphor breaking into smaller *** phosphors were characterized by laser light scattering for particle size distribution,scanning electron microscopy(SEM),transmission electron microscopy for morphologies,X-ray diffraction refinements for crystal structure and electron energy-loss spectroscopy for elemental *** is demonstrated that the median diameter(D_(50)) of the phosphor particle size is significantly reduced from 19.1 to 0.96 μm yet the photoluminescent properties have little *** carbon coating and further heat treatment method show potential application in size control of phosphors.

关键词： Y_(3)Al_(5)O_(12):Ce phosphor Particle size reduction Carbon coating Rare earths

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Multiple cycles of glacier advance and retreat during the Nantuo （Marinoan） glacial termination in the Three Gorges area

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Frontiers of Earth Science 2012年第1期6卷 101-108页

作者： Jun HU Jiasheng WANG hongren chen Zhou WANG Lei XIE Qi LIN State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430073China Faculty of Earth Sciences China University of GeosciencesWuhan 430073China

The Snowball Earth hypothesis suggests that the sea water had totally been kept frozen for millions of years in Neoproterozoic glaciation, followed by a rapid and catastrophic deglaciation resulting from the elevated concentration of atmospheric CO〉 However, the sedimen- tary records are not consistent with the Snowball Earth hypothesis. The Nantuo Formation in Three Gorges area is composed of diamictites, sandstones and siltstones. The geochronology and the unconformity with underlying Liantuo Formation indicate that the Nantuo Formation in Three Gorges area may be the partial record （i.e., the final stage） of the Nantuo glaciation. Our studies on sedimentary successions of the Nantuo Formation convince the stepwise transition from the Cryogenia icehouse to the Ediacaran greenhouse, in which multiple glacier advance- retreat cycles rather than a catastrophic termination could be identified.

关键词： multiple glacier advance-retreat cycles Neo-proterozoic Three Gorges area glaciomarine environment,Snowball Earth hypothesis

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Characteristics of authigenic pyrites in shallow core sediments in the Shenhu area of the northern South China Sea: Implications for a possible mud volcano environment

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Science China Earth Sciences 2013年第3期56卷 541-548页

作者： XIE Lei WANG JiaSheng WU NengYou WU DaiDai WANG Zhou ZHU XiaoWei HU Jun chen hongren LIN Qi State Key Laboratory of Biogeology and Environmental Geology (China University of Geosciences) Faculty of Earth Science China University of Geosciences Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Guangzhou Center for Gas Hydrate Research Chinese Academy of Sciences Guangzhou Institute of Geochemistry Chinese Academy of Sciences

Distinct pyrites have been recovered from a shallow sediment core from Site 4B in the Shenhu area of the northern South China Sea. Based on the lithology, texture and structure of sediments, the stable sulfur isotope of pyrite and the total organic carbon (TOC) concentration of the sediments, a distinctive sediment interface is identified at a depth of about 1 m below the seafloor in the core sediments. The pyrites only accumulate in the lower part of the core as rods and foraminifera-infillings, and mainly within three intervals marked by high pyrite concentrations. The amount of pyrite in the sediments shows no remarkable correlation with TOC in the Site 4B core sediments. The stable sulfur isotopes of the pyrite have extremely negative values ranging from 41.69‰ to 49.16‰. They are considered to be the mutual product of sulfate bacterial reduction and sulfur bacterial disproportionation. Our research proposes that Site 4B might be located in or near a possible mud volcano sedimentary environment; a large amount of methane could migrate from deep to shallow sediments in an active mud volcano and thereby play a key role in the intensity of sulfate bacterial reduction and the amount of pyrite formed at Site 4B. Further, the variation in flux of deep methane fluid by intermittent mud volcanic eruptions might result in the deposition of authigenic pyrite intervals.

关键词： pyrite distribution sulfur isotope shallow sediment Shenhu area

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Research About the Method of Sensitivity Analysis and Quality Control Based on LS-SVM

Research About the Method of Sensitivity Analysis and Qualit...

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2015年中国智能自动化学术会议

作者： Yiyong Yao hongren chen Liping Zhao Guangzhou Diao School of Mechanical Engineering Xi’an Jiaotong University State Key Laboratory for Manufacturing Systems Engineering Xi’an Jiaotong University

Focusing on the real-time quality control in machining process, sensitivity analysis method based on LS-SVM was proposed in this paper to control the quality of products. The relationship between machining quality and influence factors is built by LS-SVM(least squares support vector machine). Sensitivity and contribution rate are calculated in sensitivity analysis. The quality of products can be controlled by controllable factors according to the result of sensitivity analysis,and the control effect can be evaluated by quality loss function. The method verification was conducted by a simulation example. At the end of this paper, a case about globoidal cam was presented to verify the feasibility and accuracy.

关键词： LS-SVM Machining quality Sensitivity analysis Quality control

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YAG:Ce3+荧光粉性能优化与颗粒细化研究

YAG:Ce3+荧光粉性能优化与颗粒细化研究

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作者：陈泓任成都理工大学

学位级别：硕士

掺杂稀土元素Ce的钇铝石榴石荧光粉(YAG:Ce)在蓝光激发下能发出明亮的黄光,是一种成熟的商用荧光材料。由YAG:Ce荧光粉和发射蓝光的In Ga N芯片组合制成的白光LED器件广泛应用于照明、显示等领域,具有节能、高光效、使用寿命长等优点。Y... 详细信息

掺杂稀土元素Ce的钇铝石榴石荧光粉(YAG:Ce)在蓝光激发下能发出明亮的黄光,是一种成熟的商用荧光材料。由YAG:Ce荧光粉和发射蓝光的In Ga N芯片组合制成的白光LED器件广泛应用于照明、显示等领域,具有节能、高光效、使用寿命长等优点。YAG:Ce荧光粉的发光性能会直接影响白光LED的亮度、色温、色坐标等性能参数。提高现有YAG:Ce荧光粉的性能可以有效提高白光LED的光效,对于制备高效光源和减少能源消耗有重要意义。除了发光性能,粒径对荧光粉的应用也有重要影响。由于新一代显示技术Micro-LED中LED芯片尺寸已减小至50μm以内,荧光粉尺寸也必须相应减小才能与之配合,而传统高温固相法制备的荧光粉粒径在10μm以上,不能满足Micro-LED技术的要求。探索减小YAG:Ce荧光粉粒径的方法也就成为了Micro-LED技术发展的技术难点之一。另外,即使在普通白光LED中,粒径小、分布窄的荧光粉在封装后亦可获得更优的发光效果。本文聚焦于石墨相氮化碳(g-CN)表面包覆增强YAG:Ce荧光粉发光效率和碳包覆热处理细化颗粒以拓展其应用领域两方面进行研究。采用石墨相氮化碳(g-CN)对YAG:Ce进行表面包覆以优化提高荧光粉的发光性能。石墨相氮化碳是一种新型聚合物半导体材料,具有高效吸收可见光、制备简便、原料易得以及电子性能可控等优点,可作为发光材料和光催化材料。石墨相氮化碳能在紫外-可见光激发下发出460 nm蓝光,发射波长与YAG:Ce激发波长(约460 nm)一致。我们首先在YAG:Ce荧光粉表面包覆g-CN,制备出具有核壳结构的YAG@CN,随后对包覆g-CN的YAG:Ce进行热处理以进一步优化其性能。研究了g-CN包覆对YAG:Ce荧光粉发光性能的提升作用,并对样品的晶体结构、表面形貌、元素分布进行了分析。结果表明,通过液相法可在YAG:Ce荧光粉颗粒的表面上成功包覆g-CN,包覆后g-CN与YAG:Ce之间产生协同效应有利于提高YAG:Ce发光性能。对包覆后的样品进行热处理可以提高包覆层的结晶度,消除部分缺陷,从而增强协同效应的作用,最终使YAG:Ce荧光粉发光强度提高26%。包覆及热处理过程中没有引入杂相,YAG晶体结构也并未改变。此外,由于包覆层减弱了Ce在高温下的氧化,经过包覆处理的荧光粉热稳定性也有提高。采用碳包覆并热处理的方法对商业YAG:Ce荧光粉进行改性,减小荧光粉的粒径。以乙炔为碳源,使用化学气相沉积(CVD)对YAG:Ce荧光粉进行碳包覆,接着进行热处理除去碳层。热处理过程中碳与荧光粉内氧结合生成CO或CO,反应过程中荧光粉颗粒被割裂造成粒径减小。粒度测试结果表明荧光粉的中值粒径(D50)经包覆和热处理后由19.1μm下降到1.44μm。改性后的荧光粉颗粒出现了一定团聚现象,而用硝酸加热洗涤可以明显改善团聚。酸洗后荧光粉中值粒径进一步减小为0.96μm。荧光光谱表征说明改性后YAG:Ce发光性能基本不变,保证了其应用价值。这种碳包覆热处理的荧光粉颗粒细化方法有望应用于Micro-LED显示技术中。

关键词： YAG:Ce3+荧光粉性能优化颗粒细化 g-C3N4 Micro-LED

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自蔓延高温合成Ti_2SnC粉体及反应机理的研究

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材料导报 2016年第14期30卷 84-87页

作者：孙和鑫宋柏萱陈红任朱春城哈尔滨师范大学化学化工学院哈尔滨150025

采用自蔓延高温合成技术制备了Ti_2SnC粉体材料,利用XRD、SEM、EDS、TEM及DTA等分析手段对其形貌结构进行表征,在室温条件下其晶格参数a和c分别为3.186和13.630。分析了Ti2SnC的形成机制。在Ti-Sn-C反应体系中,Sn在232℃时熔化为液... 详细信息

采用自蔓延高温合成技术制备了Ti_2SnC粉体材料,利用XRD、SEM、EDS、TEM及DTA等分析手段对其形貌结构进行表征,在室温条件下其晶格参数a和c分别为3.186和13.630。分析了Ti2SnC的形成机制。在Ti-Sn-C反应体系中,Sn在232℃时熔化为液态,随着温度的升高,钛包裹在碳的外面形成钛碳层,继续加热Ti和Sn反应生成Ti-Sn金属间化合物TixSny,如Ti_6Sn_5和Ti_5Sn_3,在800℃左右钛碳层形成了TiC,在1100℃左右TiC与TixSny发生反应生成类盘状的Ti_2SnC。

关键词： Ti2SnC 自蔓延高温合成反应机理

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IODP311航次底栖有孔虫碳稳定同位素对天然气水合物地质系统的指示

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地球科学进展 2008年第11期23卷 1161-1166页

作者：李清王家生王晓芹陈祈陈洪仁中国地质大学生物地质与环境地质教育部重点实验室湖北武汉430074 中国地质大学地球科学学院湖北武汉430074 中石化江汉油田勘探开发研究院湖北潜江433124

为了探索海洋天然气水合物背景下有孔虫特征的响应,对综合大洋钻探计划(IODP)311航次岩芯沉积物中底栖有孔虫Uvigerina peregrina和Bulimina mexicana进行了初步研究。通过对冷泉站位U1328和毗邻的非冷泉站位U1327沉积物中底栖有孔虫Uvi... 详细信息

为了探索海洋天然气水合物背景下有孔虫特征的响应,对综合大洋钻探计划(IODP)311航次岩芯沉积物中底栖有孔虫Uvigerina peregrina和Bulimina mexicana进行了初步研究。通过对冷泉站位U1328和毗邻的非冷泉站位U1327沉积物中底栖有孔虫Uvigerina peregrina和Buliminamexicana的显微形貌特征和碳、氧稳定同位素测试等,证实有孔虫壳体未受到后期成岩作用的改造和自生碳酸盐岩的交代影响,有孔虫壳体的碳稳定同位素呈现明显的负偏。其中U1327站位中***δ13C为-0.67‰^-2.75‰(PDB),***δ13C为-0.51‰^-1.52‰(PDB);U1328站位中***δ13C为-0.72‰^-2.71‰(PDB),***δ13C为-0.58‰^-1.45‰(PDB)。底栖有孔虫壳体的碳稳定同位素负偏成因可能与水合物不稳定分解释放的甲烷厌氧氧化作用和食物源有关,因而可较好地指示海底天然气水合物系统地质背景。

关键词： IODP311 天然气水合物地质系统甲烷渗漏底栖有孔虫碳稳定同位素

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