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Scanning electron microscopy coupled with energydispersive X-ray spectrometry for quick detection of sulfuroxidizing bacteria in environmental water samples 被引量:1
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作者 孙承君 蒋凤华 +5 位作者 高伟 李小云 于延珍 尹晓斐 王勇 丁海兵 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第1期185-191,共7页
Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not mee... Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not meet the requirements of analysis for time-sensitive samples and/or complicated environmental samples. Since energy-dispersive X-ray spectrometry(EDS) can be used to simultaneously detect multiple elements in a sample, including sulfur, with minimal sample treatment, this technology was applied to detect sulfur-oxidizing bacteria using their high sulfur content within the cell. This article describes the application of scanning electron microscopy imaging coupled with EDS mapping for quick detection of sulfur oxidizers in contaminated environmental water samples, with minimal sample handling. Scanning electron microscopy imaging revealed the existence of dense granules within the bacterial cells, while EDS identified large amounts of sulfur within them. EDS mapping localized the sulfur to these granules. Subsequent 16S rRNA gene sequencing showed that the bacteria detected in our samples belonged to the genus Chromatium, which are sulfur oxidizers. Thus, EDS mapping made it possible to identify sulfur oxidizers in environmental samples based on localized sulfur within their cells, within a short time(within 24 h of sampling). This technique has wide ranging applications for detection of sulfur bacteria in environmental water samples. 展开更多
关键词 扫描电子显微镜 硫氧化细菌 快速检测 能量色散 环境水样 X射线光谱法 环境样品分析 基因测序技术
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Energy-dispersive X-ray Spectroscopy for the Quantitative Analysis of Pyrite Thin Specimens
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作者 LUO Tingting GUO Yi +4 位作者 DENG Zhao LIU Xiaoqing SUN Zhenya QI Yanyuan YANG Meijun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第6期1304-1310,共7页
To explore ways to improve the accuracy of quantitative analysis of samples in the micrometer to nanometer range of magnitudes,we adopted analytical transmission electron microscopy(AEM/EDS)for qualitative and quantit... To explore ways to improve the accuracy of quantitative analysis of samples in the micrometer to nanometer range of magnitudes,we adopted analytical transmission electron microscopy(AEM/EDS)for qualitative and quantitative analysis of pyrite materials.Additionally,the k factor of pyrite is calculated experimentally.To develop an appropriate non-standard quantitative analysis model for pyrite materials,the experimentally calculated k factor is compared with that estimated from the non-standard quantitative analytical model of the instrument software.The experimental findings demonstrate that the EDS attached to a TEM can be employed for precise quantitative analysis of micro-and nanoscale regions of pyrite materials.Furthermore,it serves as a reference for improving the results of the EDS quantitative analysis of other sulfides. 展开更多
关键词 analytical transmission electron microscopy(AEM) energy dispersive x-ray spectroscopy(EDS) PYRITE thin specimen quantitative analysis
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Phase Identification Using Series of Selected Area Diffraction Patterns and Energy Dispersive Spectrometry within TEM
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作者 Kun-Lin Lin 《Microscopy Research》 2014年第4期57-66,共10页
Transmission electron microscopy (TEM) is a very powerful technique for materials characteriza-tion, providing information relating to morphology, composition, and crystal structure. Selected area diffraction patterns... Transmission electron microscopy (TEM) is a very powerful technique for materials characteriza-tion, providing information relating to morphology, composition, and crystal structure. Selected area diffraction patterns (SADPs) are crystallographic data that can be obtained using a TEM in-strument. Conventional identification through SADP/TEM is tricky and tedious, thereby increasing the difficulty of phase identification. To establish a procedure for phase identification of known and unknown phases, in this study we examined two samples: one, a known phase, was Si with alignment;the other, unknown, was the TixOy phase at the 96.4Au-3Ni-0.6Ti interlayer/ yttria-stabilized zirconia (YSZ) interface of a steel/96.4Au-3Ni-0.6Ti interlayer/YSZ joint. The procedures for phase identification of the known and unknown phases are described herein using a series of SADPs and energy dispersive spectrometry within TEM that would be useful for general researchers. 展开更多
关键词 Phase Identification Transmission electron microscopy SELECTED Area DIFFRACTION Pattern energy dispersive Spectroscopy
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Application of Electron Microscopic on the Sources of PM_(10) in the Atmosphere
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作者 WANG Ju YANG Meng-yao +3 位作者 WEI Qiang FANG Chun-sheng CHEN Ke-hua XIAO Zhong-shen 《Meteorological and Environmental Research》 CAS 2012年第1期8-13,共6页
[ Objective] The aim was to study the application of scanning electron microscopy(SEM) on the physical property and ideological distri- bution of partials. [ Method] By dint of scanning electron microscopy, the morp... [ Objective] The aim was to study the application of scanning electron microscopy(SEM) on the physical property and ideological distri- bution of partials. [ Method] By dint of scanning electron microscopy, the morphological property of each source and main elements were analyzed. Compared with morphological property of sampling point, the source of particles was determined. [ Result] The results were consistent with the analysis of CMB8.2 chemical mass balance receptor model. Taking the four detection stations in Longyan Normal Training College, Minxi Vocational & Technical College, Longyan University, and Longyan Environment Monitoring Station as examples, the major air pollutants respectively were soil sand, dust of burning coal, second fugitive dust; soil sand, second fugitive dust, vehicle exhausts; second fugitive dust, soil; and second fugitive dust, vehicle exhausts, dust of burning coal. [ Conclusion] The study result had certain guiding significance to the analysis of sources of particles in the atmosphere and atmosphere environment treatment. 展开更多
关键词 PM10 Scanning electron microscopy x-ray energy dispersive spectrum CMB receptor model China
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Mineral Particles Found on the Hairs of Holy Maria-Magdalena Studied by Scanning Electron Microscopy and Elemental Analysis
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作者 Gérard Lucotte 《Open Journal of Applied Sciences》 2020年第3期41-59,共19页
The presumed hairs of Holy Maria-Magdalena are studied here for mineral particles found on their surfaces, by the techniques of scanning electron microscopy coupled with energy dispersive X-ray. Exploration by these t... The presumed hairs of Holy Maria-Magdalena are studied here for mineral particles found on their surfaces, by the techniques of scanning electron microscopy coupled with energy dispersive X-ray. Exploration by these techniques of the hair surfaces allows us to observe and study some marble fragments that can originate from the walls of the sarcophagus in which Maria-Magdalena’s remains were kept. These new findings support the authenticity of the hair as traditionally reported in the French “tradition des Saints de Provence”. 展开更多
关键词 Maria-Magdalena’s HAIR Scanning electron microscopy energy Disper-sive x-ray MARBLE FRAGMENTS MINERAL Particles
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Neutron Activation Analysis and Scanning Electron Microscopy of Phytoplankton in the Coastal Zone of Crimea (The Black Sea)
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作者 P. S. Nekhoroshkov A. V. Kravtsova +1 位作者 M. V. Frontasyeva Yu. N. Tokarev 《American Journal of Analytical Chemistry》 2014年第5期323-334,共12页
The physiology and ecology of planktonic organisms are influenced by the concentration, chemical speciation and resulting bioavailability of some trace metals. The determination of the elemental structure of phytoplan... The physiology and ecology of planktonic organisms are influenced by the concentration, chemical speciation and resulting bioavailability of some trace metals. The determination of the elemental structure of phytoplankton is important for interpretation of physiological and functional states of coastal ecosystems. The present study is focused on the structure and elemental composition of the phytoplankton assemblages from the different coastal zones by instrumental neutron activation analysis (INAA), scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry (EDS). For the first time these complementary techniques were simultaneously applied to study the Black Sea phytoplankton. The concentrations of 45 elements in the coastal phytoplankton communities used as bioindicator of inorganic contamination of the Black Sea coastal area near Sevastopol, Ukraine, were determined. Phytoplankton samples were collected by total tows of the plankton net with 35 μm pore size at 3 stations situated in polluted and relatively pristine water areas of the Sevastopol coastal zone during autumn period of the phytoplankton growth. The concentration of Mg, Al, Sc, Ti, V, Mn, As, Rb, Ba, Th and Fe, Cr increases exponentially from relatively pristine station to more polluted station and 10-times and 3-times greater, respectively, in the phytoplankton of the Sevastopol Bay. The rare-earth elements have relatively the same concentration values less than 1 μg/g and tend to accumulate in the phytoplankton from the polluted station in the Sevastopol Bay. The obtained results are in a good agreement with the elemental concentration data in the oceanic plankton, plankton communities from the White Sea and the Black Sea. Using energy-dispersive X-ray spectrometry the mineral particles of unknown origin and impurities of copper (0.42% by weight) in the phytoplankton at the polluted station and zinc (0.57% by weight) at the relatively pristine station were determined. 展开更多
关键词 Black Sea PHYTOPLANKTON Scanning electron microscopy NEUTRON Activation Analysis energy-dispersive x-ray SPECTROMETRY TRACE Elements
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馆藏汉代瓦当表面可溶盐的化学组成分析
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作者 荆海燕 马芬 +2 位作者 郑丽珍 白璐 付文斌 《分析科学学报》 CAS CSCD 北大核心 2024年第2期244-248,共5页
采用离子色谱仪(IC),扫描电子显微镜-能谱仪(SEM-EDS),X射线衍射仪(XRD)和傅里叶变化显微红外光谱仪(FTIR)等现代分析仪器,对陕西历史博物馆馆藏的汉代瓦当表面可溶盐进行了鉴定,并分析了相关的化学组成。结果表明,瓦当表面可溶盐含有石... 采用离子色谱仪(IC),扫描电子显微镜-能谱仪(SEM-EDS),X射线衍射仪(XRD)和傅里叶变化显微红外光谱仪(FTIR)等现代分析仪器,对陕西历史博物馆馆藏的汉代瓦当表面可溶盐进行了鉴定,并分析了相关的化学组成。结果表明,瓦当表面可溶盐含有石膏(Ca SO_(4)·2H_(2)O)和有机酸钙盐[Ca_(3)(CH_(3)COO)_(3)Cl(NO_(3))_(2)·6H_(2)O]等成分。 展开更多
关键词 瓦当 可溶盐 扫描电子显微镜-能谱 X射线衍射 离子色谱
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扫描电子显微镜和能谱仪在玻璃结石成分分析中的应用 被引量:1
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作者 李总盛 杨启乐 +3 位作者 张海翔 李从英 赵仔叶 穆树兰 《玻璃搪瓷与眼镜》 CAS 2024年第2期7-12,23,共7页
玻璃中常见各种结石缺陷,利用透反偏光显微镜可以初步判定玻璃结石的种类,但无法分析结石的成分,且处理样品效率较低。以硅质析晶结石、铝质耐火材料结石、锆质耐火材料结石为例,利用扫描电子显微镜和能谱仪分析结石,可以快速测定结石成... 玻璃中常见各种结石缺陷,利用透反偏光显微镜可以初步判定玻璃结石的种类,但无法分析结石的成分,且处理样品效率较低。以硅质析晶结石、铝质耐火材料结石、锆质耐火材料结石为例,利用扫描电子显微镜和能谱仪分析结石,可以快速测定结石成分,辨别结石种类,进而推断结石形成的原因。采用该方法可及时准确调整生产,解决玻璃生产中产生结石问题。 展开更多
关键词 玻璃结石 扫描电子显微镜 能谱仪 透反偏光显微镜
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金属物证检验及其在法庭科学领域中的应用
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作者 周正 李光耀 +7 位作者 孙振文 刘占芳 张冠男 李亚军 郑继利 李鹏 朱军 蔡金 《刑事技术》 2024年第3期304-312,共9页
金属物证在法庭科学领域的应用由来已久,其检验通常归于微量物证的检验范畴。金属物证通常以金属颗粒、附着物或熔融态出现在杀人、盗窃、枪击、电气火灾等多种类型的案事件中,检验方法通常包括扫描电镜–能谱法、金相检验法、X射线荧... 金属物证在法庭科学领域的应用由来已久,其检验通常归于微量物证的检验范畴。金属物证通常以金属颗粒、附着物或熔融态出现在杀人、盗窃、枪击、电气火灾等多种类型的案事件中,检验方法通常包括扫描电镜–能谱法、金相检验法、X射线荧光光谱法、电感耦合等离子体质谱法等多种方法。通过金属物证的检验,可以起到确定案事件性质、提供侦查线索以及完善证据链的作用。本文通过对近年来国内法庭科学领域金属物证检验文献进行提取,以知识图谱分析工具VOSviewer进行分析,就金属物证的多种检验方法进行综述,了解其在法庭科学领域的应用现状,旨在为涉案金属物证的提取和检验提供借鉴作用。 展开更多
关键词 法庭科学 微量物证 金属物证 扫描电镜–能谱法 金相法 X射线荧光光谱法 电感耦合等离子体质谱法
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Hematite, Biotite and Cinnabar on the Face of the Turin Shroud: Microscopy and SEM-EDX Analysis
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作者 Gérard Lucotte Thierry Derouin Thierry Thomasset 《Open Journal of Applied Sciences》 2016年第9期601-625,共26页
The Turin Shroud, recently accessible for hands-on scientific research, is now extensively investigated. Its pinkish red blood stains that seem anomalous ones are studied by modern techniques (notably by resolute opti... The Turin Shroud, recently accessible for hands-on scientific research, is now extensively investigated. Its pinkish red blood stains that seem anomalous ones are studied by modern techniques (notably by resolute optical microscopy and scanning electron microscopy coupled with energy dispersive X-ray). Exploration by these techniques of a blood stain located on the face permits us to discover some red-colour particles (hematite, biotite and cinnabar) of exogenous material in this stain. We finally characterize these red-colour particles and try to explain their presences in the blood stain. Globally, all these red-colour particles cannot explain all of the reddish appearance of the area under study. 展开更多
关键词 Turin Shroud Blood Stains Face Area HEMATITE BIOTITE CINNABAR Optical microscopy Scanning electron microscopy energy dispersive x-ray
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南海海泥中甲烷水合物的形貌及赋存特性 被引量:2
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作者 张凯 吕秋楠 +2 位作者 李刚 李小森 莫家媚 《化工进展》 EI CAS CSCD 北大核心 2023年第7期3865-3874,共10页
水合物表观形貌受水合物的生长方式影响,能够反映水合物在沉积物中的分布以及与沉积物的空间关系,进而对含水合物沉积物的物理特性产生影响。本文通过在实际钻采的南海神狐海域水深2713m的海泥中生成甲烷水合物,利用冷冻扫描电子显微镜(... 水合物表观形貌受水合物的生长方式影响,能够反映水合物在沉积物中的分布以及与沉积物的空间关系,进而对含水合物沉积物的物理特性产生影响。本文通过在实际钻采的南海神狐海域水深2713m的海泥中生成甲烷水合物,利用冷冻扫描电子显微镜(Cryo-SEM)和能谱仪(EDS)对合成水合物的微观形貌、元素组成进行表征。结果表明,与冰相比,纯水体系下的甲烷水合物形貌单一且容易分解。纯水体系生成的水合物与海泥体系生成的水合物形貌相似,均呈颗粒胶结状,微量纳米级别的颗粒冰分布在表面。元素分析表明相较于纯水体系,海泥中生成的水合物C元素含量更高,水合物笼子占有率也越高。海泥中含有微量的C元素,通过C元素含量增加及C、Si比提高确定了表面颗粒胶结状为水合物。本研究为辨别沉积物中的水合物提供了新思路,为研究水合物的表观形貌及赋存提供了重要方法。 展开更多
关键词 海泥 甲烷 水合物 表面形貌 扫描电镜和能谱仪
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偏硼酸锂熔融-电感耦合等离子体发射光谱法结合扫描电镜-能谱测定锡矿石中锡钨锌铜铁锰 被引量:3
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作者 王冠 董俊 +1 位作者 徐国栋 胡志中 《岩矿测试》 CAS CSCD 北大核心 2023年第1期114-124,共11页
锡石不溶于盐酸、硝酸及王水,测定其中元素含量时通常采用碱熔融分解样品,电感耦合等离子体发射光谱法(ICP-OES)测定。而传统的过氧化钠或其他氧化性熔剂会引入大量的盐类,酸化提取后的溶液需要进一步分离或稀释,这样不仅影响分析的准... 锡石不溶于盐酸、硝酸及王水,测定其中元素含量时通常采用碱熔融分解样品,电感耦合等离子体发射光谱法(ICP-OES)测定。而传统的过氧化钠或其他氧化性熔剂会引入大量的盐类,酸化提取后的溶液需要进一步分离或稀释,这样不仅影响分析的准确度及较低含量元素的测定限,长时间测定还会引起等离子体信号降低,造成仪器损伤。本文将锡矿石经偏硼酸锂熔融,超声波水浴处理,用ICP-OES法同时测定锡、钨、铁、锰、铜、锌元素含量,在标准溶液中匹配等量锂盐,各待测元素之间无明显干扰,操作简单快捷,环境污染小。实验过程中结合扫描电镜-能谱(SEM-EDX)微区分析技术,观察和分析不同熔剂量下样品熔珠的形貌特征和成分差异,发现随着熔剂与样品比例从小至大,熔珠表面结构呈现由松散、易碎向细粒、致密均匀的规律性变化,当熔剂与样品的比例达到7∶1后,熔珠表面形态无明显变化,当熔剂与样品的比例为8∶1时,熔珠表面能明显检测出硼元素的存在,说明此时的熔剂过量,从而实现了应用SEM-EDX技术来确定ICP-OES法分析中熔剂与样品的最佳配比。本研究还探讨了锡矿石样品的熔融温度和时间、介质酸度,对锡矿石标准物质GBW07281进行分析测定,方法精密度(RSD)为1.20%~8.06%,方法检出限为0.0012%~0.0098%,满足了样品中元素定量分析的要求。 展开更多
关键词 锡矿石 金属元素 偏硼酸锂熔融 电感耦合等离子体发射光谱法 扫描电镜-能谱
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故宫奉先殿后殿神龛营缮历史与髹饰工艺考 被引量:1
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作者 刘梦雨 卓媛媛 《建筑史学刊》 2023年第1期77-96,共20页
奉先殿是紫禁城内皇室祭祀祖先的家庙,重建于顺治年间,后殿内原设11座神龛,供奉清朝历代帝后神位,20世纪60年代因展览改造,神龛拆卸解体,收归库房保存。各座神龛为清朝历代依次修造,形制与装饰做法高度相近。科学检测表明,神龛表面装饰... 奉先殿是紫禁城内皇室祭祀祖先的家庙,重建于顺治年间,后殿内原设11座神龛,供奉清朝历代帝后神位,20世纪60年代因展览改造,神龛拆卸解体,收归库房保存。各座神龛为清朝历代依次修造,形制与装饰做法高度相近。科学检测表明,神龛表面装饰层均以传统大漆髹饰,露明位置满贴金箔,不露明位置或使用单漆做法。各时期的髹饰做法大体遵循同一套规范工序:在木基层上依次做捎当灰—布漆—漆灰—糙漆(垫光漆)—朱漆,而后在朱漆表面贴金,最后涂刷掺有桐油的透明罩漆。这与《髹饰录》和清代漆作则例等文献记载高度吻合。综合比对检测结果与文献史料,可以确认,神龛装饰层在清代共经历两次有据可查的修缮,一次是道光元年(1821)孝淑睿皇后神龛的赔修,简单修补了表面漆饰;一次是道光二年(1822)前七座神龛的全面大修,修改了木胎尺寸,并将漆饰整体见新。另外,第四座神龛在雍正至嘉庆年间还有过一次针对漆饰的零修。道光及道光之后所修造的末四座神龛,在落成后未再经历任何修缮。不同时期的金箔成色有别,导致各座神龛的金饰色调并不完全相同。 展开更多
关键词 清代 奉先殿 神龛 大漆 贴金 光学显微分析 扫描电镜-X射线能谱(SEM-EDS)分析
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Possible Relevance of the Allende Meteorite Conditions in Prebiotic Chemistry: An Insight into the Chondrules and Organic Compounds
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作者 Alejandro Heredia Barbero Héctor G. Vázquez López +8 位作者 Adriana L. Meléndez López Jorge A. Cruz Castañeda Daniel Luna Laviada Karina E. Cervantes de la Cruz Victor Meza Laguna Vladimir A. Basiuk Ivonne Rosales Chávez Alicia Negrón Mendoza Sergio Ramos Bernal 《Advances in Biological Chemistry》 2023年第3期82-99,共18页
The study of the mineral and organic content of the Allende meteorite is important for our understanding of the molecular evolution of the universe as well as the ancient Earth. Previous studies have characterized the... The study of the mineral and organic content of the Allende meteorite is important for our understanding of the molecular evolution of the universe as well as the ancient Earth. Previous studies have characterized the magnetic minerals present in ordinary and carbonaceous chondrites, providing information on the evolution of magnetic fields. The interaction of organic compounds with magnetic minerals is a possible source of chemical diversity, which is crucial for molecular evolution. Carbon compounds in meteorites are of great scientific interest for a variety of reasons, such as their relevance to the origins of chirality in living organisms. This study presents the characterization of organic and mineral compounds in the Allende meteorite. The structural and physicochemical characterization of the Allende meteorite was accomplished through light microscopy, powder X-ray diffraction with complementary Rietveld refinement, Raman and infrared spectroscopy, mass spectrometry, scanning electron microscopy, and atomic force microscopy using magnetic signal methods to determine the complex structure and the interaction of organic compounds with magnetic Ni-Fe minerals. The presence of Liesegang-like patterns of chondrules in fragments of the Allende structure may also be relevant to understanding how the meteorite was formed. Other observations include the presence of magnetic materials and nanorod-like solids with relatively similar sizes as well as the heterogeneous distribution of carbon in chondrules. Signals observed in the Raman and infrared spectra resemble organic compounds such as carbon nanotubes and peptide-like molecules that have been previously reported in other meteorites, making the Mexican Allende meteorite a feasible sample for the study of the early Earth and exoplanetary bodies. 展开更多
关键词 Allende Meteorite Carbonaceous Chondrite Light microscopy x-ray Diffraction with the Rietveld Method Raman Spectroscopy Attenuated Total Reflectance Infrared Spectroscopy Mass Spectrometry Scanning electron Mi-croscopy energy dispersive x-ray Spectroscopy Magnetic Force microscopy
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广西桂西地区沉积型铝土矿矿物特征研究
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作者 韦连军 陈燕清 +1 位作者 雷满奇 黄庆柒 《岩矿测试》 CAS CSCD 北大核心 2023年第6期1220-1229,共10页
随着中国铝土矿资源日益消耗,高硫铝土矿将成为重要的新型铝土矿资源。中国有大量品位较高的高硫型沉积型铝土矿,但这类矿石由于硫含量高(硫含量>0.7%),严重影响后续提铝工艺流程,因而一直未被工业化利用,在铝土矿资源日益紧缺之时,... 随着中国铝土矿资源日益消耗,高硫铝土矿将成为重要的新型铝土矿资源。中国有大量品位较高的高硫型沉积型铝土矿,但这类矿石由于硫含量高(硫含量>0.7%),严重影响后续提铝工艺流程,因而一直未被工业化利用,在铝土矿资源日益紧缺之时,若能开发利用,对中国铝工业发展具有重要意义。2020—2021年在广西桂西地区自平果—靖西一带铝土矿成矿带新探获得相当量的沉积型铝土矿,该沉积型铝土矿是堆积型铝土矿的矿源层,二者在空间分布上存在重叠,矿石多与黄铁矿密切共生,部分矿段的硫含量高出工业利用允许最高含量的数倍或数十倍,尽管矿石品位较高,但硫含量多在2%~8%,目前该铝土矿矿石性质及工业化技术指标尚不明确。因此,本文以广西桂西地区的沉积型铝土矿为研究对象,采用X射线荧光光谱、偏光显微镜、X射线衍射及扫描电镜-能谱等分析测试技术研究了铝土矿的矿石矿物组成特性,探究了沉积型铝土矿的矿石性质。分析结果表明,该矿石中Al2O3含量为64.21%,S含量为5.13%,属于高硫沉积型铝土矿;矿石中铝矿物主要为一水硬铝石、绿泥石;铁矿物主要有黄铁矿、赤铁矿及褐铁矿;一水硬铝石,其结晶粒度细,呈鲕状集合体形式,表面较光滑;黄铁矿中粗粒、中粒级黄铁矿多以半自形及他形存在,粒径较大。结合本项目组早前对高硫型铝土矿进行的大量试验研究认为,该沉积型铝土矿高硫问题可通过选矿技术方法分离黄铁矿,后续建议通过破碎磨矿手段使矿石矿物单体解离,再辅以合理的选矿药剂制度将黄铁矿浮选分离出来,从而使浮硫后的含铝矿物满足下一步的氧化铝提取入料要求。 展开更多
关键词 沉积型铝土矿 矿物特征 黄铁矿 X射线荧光光谱法 X射线衍射法 扫描电镜-能谱法
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单分散纳米SiO_2的制备及其作为润滑油添加剂的摩擦学性能研究 被引量:56
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作者 霍玉秋 闫玉涛 +3 位作者 刘晓霞 丁津原 翟玉春 田彦文 《摩擦学学报》 EI CAS CSCD 北大核心 2005年第1期34-38,共5页
以正硅酸乙酯为原料制备了单分散纳米SiO2并表征了其结构,利用四球摩擦磨损试验机测定了所制备的纳米SiO2作为500SN基础油添加剂的摩擦学性能.结果表明:所制备的SiO2为粒径60nm左右的球形微粒,其表面含有大量羟基,具有无定形晶体结构;纳... 以正硅酸乙酯为原料制备了单分散纳米SiO2并表征了其结构,利用四球摩擦磨损试验机测定了所制备的纳米SiO2作为500SN基础油添加剂的摩擦学性能.结果表明:所制备的SiO2为粒径60nm左右的球形微粒,其表面含有大量羟基,具有无定形晶体结构;纳米SiO2作为添加剂可以显著提高500SN基础油的承载能力和抗磨性能,当纳米SiO2的添加量为2.0%时,相应的pB值最高、磨斑直径最小、摩擦系数最低. 展开更多
关键词 纳米SIO2 添加剂 500SN基础油 摩擦学性能
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胞外聚合物对生物除磷效果影响研究 被引量:28
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作者 刘亚男 于水利 +2 位作者 赵冰洁 郭思远 芮道强 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2005年第5期623-625,共3页
为考察3种不同碳源(乙酸钠、葡萄糖、脱脂乳和葡萄糖混合物)SBR生物除磷系统的除磷效果,用结合扫描电镜(SEM)的能谱(EDS)分析了胞外聚合物(EPS)的磷含量,并测定了污泥PHA(poly-β-hydroxyalkanoate)及磷含量.结果表明,PHA在厌氧结束时... 为考察3种不同碳源(乙酸钠、葡萄糖、脱脂乳和葡萄糖混合物)SBR生物除磷系统的除磷效果,用结合扫描电镜(SEM)的能谱(EDS)分析了胞外聚合物(EPS)的磷含量,并测定了污泥PHA(poly-β-hydroxyalkanoate)及磷含量.结果表明,PHA在厌氧结束时的量并不是后续好氧阶段吸磷效果好坏的决定性指标,EPS的生物吸附对磷也有一定程度的去除,并且这种生物吸附使葡萄糖碳源系统除磷效果好于其他两个系统. 展开更多
关键词 生物除磷 胞外聚合物 能谱 生物吸附
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不同污染程度下毛白杨叶表面PM_(2.5)颗粒的数量及性质和叶片气孔形态的比较研究 被引量:30
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作者 石婕 刘庆倩 +5 位作者 安海龙 曹学慧 刘超 尹伟伦 郭惠红 夏新莉 《生态学报》 CAS CSCD 北大核心 2015年第22期7522-7530,共9页
选择了北京市环境PM_(2.5)浓度不同的两个采样点的毛白杨(Populus tomentosa Carr.)作为研究对象,利用环境扫描电镜及X-射线能谱仪对杨树叶片表面滞留的PM_(2.5)颗粒进行了观察、统计和成分分析,并研究了叶片气孔对环境颗粒物污染的适... 选择了北京市环境PM_(2.5)浓度不同的两个采样点的毛白杨(Populus tomentosa Carr.)作为研究对象,利用环境扫描电镜及X-射线能谱仪对杨树叶片表面滞留的PM_(2.5)颗粒进行了观察、统计和成分分析,并研究了叶片气孔对环境颗粒物污染的适应性变化。结果表明:夏秋两季西直门叶片样品上下表面的PM_(2.5)数量均多于森林公园样品这说明环境PM_(2.5)浓度是影响叶片表面滞留颗粒物数量的主要原因;其中叶片上表面是滞留PM_(2.5)颗粒的主要区域。森林公园样品中PM_(2.5)颗粒性质比较单一,硅铝酸盐颗粒和石英颗粒占很大比例,二者的主要来源均为天然源,如土壤扬尘、矿物颗粒等;而西直门采样点叶片样品滞留的PM_(2.5)颗粒的元素组成更为复杂,其中50%以上的硅铝酸盐颗粒检测出了明显的铜、钾、氯、钠等元素的谱峰其来源主要是工业排放;西直门样品PM_(2.5)的含硫量高于森林公园样品,且夏季明显高于秋季。研究还发现有少数PM_(2.5)颗粒进入了毛白杨叶片的气孔而且不同污染程度下气孔的形态特征存在差异。与森林公园毛白杨叶片的气孔相比,西直门处的毛白杨叶片气孔的长度、宽度、面积和气孔密度均较小,说明较高的PM_(2.5)污染程度对毛白杨叶片的形态发育有一定影响。研究结果可以为揭示植物叶片阻滞、吸收大气颗粒污染物的机制、合理选择和优化城市绿化树种从而改善空气质量提供一定的科学理论依据。 展开更多
关键词 毛白杨 叶片 PM_(2.5) 气孔 环境扫描电镜 X-射线能谱分析
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用环境扫描电镜原位定量追踪K-PSDS型地聚合物混凝土界面区的水化过程 被引量:17
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作者 张云升 孙伟 +3 位作者 林玮 郑克仁 沙建芳 刘斯凤 《硅酸盐学报》 EI CAS CSCD 北大核心 2003年第8期806-810,共5页
应用环境扫描电镜(ESEM)原位定量追踪K-PSDS型(KOH激发合成的PSDS型)地聚合物水泥混凝土在相对湿度80%条件下界面区水化产物生成、发展和演化的过程。实验结果表明:界面区和基体区的ESEM形貌在水化早期差别较大,界面区存在许多大的空洞... 应用环境扫描电镜(ESEM)原位定量追踪K-PSDS型(KOH激发合成的PSDS型)地聚合物水泥混凝土在相对湿度80%条件下界面区水化产物生成、发展和演化的过程。实验结果表明:界面区和基体区的ESEM形貌在水化早期差别较大,界面区存在许多大的空洞(50μm),而基体区颗粒分布均匀、密实;随龄期的增长,凝胶状产物在界面区空洞周缘淀积,并向外伸展,空洞逐渐被填满、湮没;到后期二者形貌基本没有太大区别,但通过能量散射分析(EDXA)发现界面区n(K)/n(Al)和n(Si)/n(Al)高于基体区,表明K和Si在界面区富集,从而造成胶凝产物化学组成的差异。另外,界面区在任何龄期均未出现尺寸规则的结晶产物,而仅生成了海绵状胶凝体。 展开更多
关键词 地聚合物水泥 界面区 水化过程 原位定量追踪 偏高岭土
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木霉(Trichoderma sp.)HR-1活细胞吸附Pb(Ⅱ)的机理 被引量:36
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作者 沈薇 杨树林 +2 位作者 李校堃 袁辉 高力虎 《中国环境科学》 EI CAS CSCD 北大核心 2006年第1期101-105,共5页
从重金属废水中筛选得到一株能够吸附Pb(II)的丝状真菌,编号为HR-1,初步鉴定其为木霉属(Trichodermasp.).研究了pH值对活细胞吸附铅离子能力的影响及其对铅的耐受性,结果表明,该细胞对铅离子的最大吸附量为597mg/g;扫描电镜(SEM)显示细... 从重金属废水中筛选得到一株能够吸附Pb(II)的丝状真菌,编号为HR-1,初步鉴定其为木霉属(Trichodermasp.).研究了pH值对活细胞吸附铅离子能力的影响及其对铅的耐受性,结果表明,该细胞对铅离子的最大吸附量为597mg/g;扫描电镜(SEM)显示细胞吸附Pb(II)后发生明显的萎缩现象,在细胞表面存在大量的沉积物;X射线光散射能谱(EDX)验证了铅的吸附,同时吸附过程中存在离子交换作用.对比细胞吸附Pb(II)前后的傅立叶红外光谱(FTIR)图谱表明,葡聚糖或几丁质中的羟基和C-O-C、蛋白质的羧基是铅的主要吸附位点,与含氮官能团无关.XPS证实细胞吸附铅离子后生成PbO,XRD图谱得出其处于无定形和晶体之间. 展开更多
关键词 细胞 生物吸附 SEM/EDX FTIR 吸附机理
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