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本文以红柱石绢云母千枚岩、NH4Al(SO4)2.12H2O、NaH2PO4.2H2O等为原料,分别在1200℃、1300℃和1400℃下制备莫来石晶须。运用X射线粉末衍射(XRD)和扫描电子显微镜(SEM)等手段,分析了莫来石晶须的形成过程和微观形貌。结果表明,当Al2O3/SiO2(摩尔比)为0.32,烧结温度1400℃,保温时间6 h,可获得长约13~20μm,长径比大于20的莫来石晶须。实验表明,只要条件控制得当,低品位的红柱石矿石也可以制取高质量的莫来石晶须。 相似文献
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利用高铝粉煤灰制备莫来石微晶玻璃的实验研究 总被引：1，自引：0，他引：1
以高铝粉煤灰为主要原料,采用粉末烧结法制备出莫来石微晶玻璃。X射线衍射分析显示,经1350~1550℃热处理后,制得的微晶玻璃的主晶相均为莫来石。扫描电镜分析表明,较高的温度下热处理有利于晶体的生长。微晶玻璃的理化性能如吸水率、气孔率、体积密度、抗折强度和化学稳定性,随热处理温度的不同而发生相应的变化。1500℃热处理2 h制得的微晶玻璃具有优良的理化性能,在工程和结构领域具有潜在的应用前景。 相似文献
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利用高铝粉煤灰制备堇青石微晶玻璃的实验研究 总被引：1，自引：0，他引：1
以高铝粉煤灰为主要原料，制备了堇青石微晶玻璃。通过差热分析（DTA）和X射线粉末衍射分析（XRD）确定了合适的热处理条件：核化温度807℃，核化时间2h，晶化温度960℃，晶化时间3h。XRD分析显示，制得微晶玻璃的主晶相为堇青石。SEM分析表明，基础玻璃晶化完全，微晶玻璃中微晶体呈不规则柱状、棒状，微晶体长度为5～15μm，长径比为5～10。 相似文献
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采用无机盐溶胶-凝胶法制备了颗粒均匀的形态为针状的(Eu2+,Dy3+)SrAl2O4纳米粉体.通过TG-DTA分析和X射线衍射和扫描电镜分析方法,对样品进行了微观结构和表面形态的表征.研究了纳米(Eu2+,Dy3+)SrAl2O4粉体在不同烧结温度下固相反应过程和成相规律.实验结果表明,当样品的烧结温度为500 ℃时是单一的Sr(NO3)2晶相;750 ℃左右生成了Sr3Al2O6,并伴有少量SrAl2O4晶体;1 100 ℃是生成了结晶度良好的针状纳米(Eu2+,Dy3+)SrAl2O4粉体.通过计算,样品粉体晶粒平均为80～100 nm.该晶体粒度随烧结温度升高而逐渐变大. 相似文献
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为综合利用固体废弃物,本文以电石渣和铁尾矿为主要原料,铝粉膏作为发气剂开展制备加气混凝土的实验研究,探讨电石渣的粒度、掺量和静停养护温度对加气混凝土物理力学性能的影响,并利用XRD分析了加气混凝土的水化产物。结果表明:当电石渣比表面积为320 m2/kg,掺量为26%(质量百分数),静停养护温度为70℃时,可以制备出绝干密度为579 kg/m3,抗压强度为4.47 MPa加气混凝土制品。电石渣中Ca(OH)2溶于水后,放热量低,不能满足加气混凝土生产的需求,需要提高外部静停养护温度,满足加气混凝土热值需要。XRD分析显示,所制备的加气混凝土中主要结晶相是0.9 nm托贝莫来石、1.1 nm托贝莫来石和1.4 nm托贝莫来石。 相似文献
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矽线石莫来石化的X射线定量分析 总被引：2，自引：0，他引：2
本文介绍用X射线粉晶衍射分析方法对夕线石在不同温度的烧制品中的莫来石进行定量分析;指出莫来石和矽线石的(220)峰可作为特征峰,并发现莫来石起始生成和完全莫来石化的温度随原料杂质和粒度因素而变化;认为d(020)=0.383 7nm,d(040)=0.191 7nm是矽线石JCPDS卡片中不曾标定的衍射峰,d(020)=0.3845nm是莫来石不曾标定的衍射峰,它们的强度变化是莫来石化行为特征之一。 相似文献
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在37℃时,配制了与人体血液等钙磷比的模拟体液(SBF),在不同pH值下合成了含钙磷酸盐。通过X射线电子衍射(XRD)、傅立叶红外吸收光谱(FTIR)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)对磷酸盐的物相组成、微观形貌进行了表征。结果表明,pH=5.9时,能生成晶型较完好的磷酸氢钙(DCPD)、磷酸八钙(OCP)和羟磷灰石(HA)的混合物,其中DCPD片状晶体长约10μm,宽约3μm;OCP片状晶体长约200 nm,宽50~100 nm;HA棒状晶体长约200 nm,宽约10 nm,HA柱状晶体长40~50 nm,宽约20 nm。pH=5.9~6.4时,HA晶体的长径比随pH值增加而增大,晶体沿c轴生长。pH6.4时,产物为HA,且其长径比随pH值的增加而减小。pH=5.9~8.9时,HA的结晶度随pH值增加而降低。实验时空气中的CO2溶入矿化液,形成的CO2-3能进入HA晶格,形成与生物成因成分特征相符的碳羟磷灰石。 相似文献
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以水镁石为原料,与盐酸反应制得氯化镁,然后将氯化镁和氨水碱溶液在室温下反应得到氢氧化镁,再通过水热处理制备出了超细、高纯的氢氧化镁颗粒,通过利用X射线衍射仪(XRD)和扫描电子显微镜(SEM)对所制得氢氧化镁颗粒的晶相、形貌和颗粒尺寸进行了表征。实验结果表明水热处理温度、填充度和搅拌速度对氢氧化镁晶体的晶相和颗粒尺寸有显著的影响,升高温度有助于改善颗粒的晶形和分散性、并减小颗粒的尺寸,较高的填充度有利于六方片状颗粒的生成,当填充度为40%,搅拌速度为400 r/min,水热处理温度为150℃时,制备出了半径约100~250 nm,厚度为10~100 nm,晶形完整,分散性好、大小均一的六方片状超细、高纯的氢氧化镁颗粒。 相似文献
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Coal‐based graphene quantum dots (GQDs) were successfully produced via a one‐step chemical synthesis from six different coal ranks, from which two superhigh organic sulfur (SHOS) coals were selected as natural S‐doped carbon sources for the preparation of S‐doped GQDs. The effects of coal properties on coal‐based GQDs were analyzed by means of high‐resolution transmission electron microscopy (HRTEM), X‐ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X‐ray photoelectron spectroscopy (XPS), ultraviolet‐visible (UV‐Vis) absorption spectroscopy, and fluorescence emission spectra. It was shown that all coal samples can be used to prepare GQDs, which emit blue‐green and blue fluorescence under ultraviolet light. Anthracite‐based GQDs have a hexagonal crystal structure without defects, the largest size, and densely arranged carbon rings in their lamellae; the high‐rank bituminous coal‐based GQDs are relatively reduced in size, with their hexagonal crystal structure being only faintly visible; the low‐rank bituminous coal‐based GQDs are the smallest, with sparse lattice fringes and visible internal defects. As the metamorphism of raw coals increases, the yield decreases and the fluorescence quantum yield (QY) initially increases and then decreases. Additionally, the surface of GQDs that were prepared using high‐rank SHOS coal (high‐rank bituminous coal) preserves rich sulfur content even after strong oxidation, which effectively adjusts the bandgap and improves the fluorescence QY. Thus, high‐rank bituminous coal with SHOS content can be used as a natural S‐doped carbon source to prepare S‐doped GQDs, extending the clean utilization of low‐grade coal. 相似文献
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Jiangrong Xiao Tianyou Peng Dingning Ke Ling Zan Zhenghe Peng 《Physics and Chemistry of Minerals》2007,34(4):275-285
CdS/rectorite nanocomposite was synthesized via a cation-exchange reaction followed by a sulfurization process. The obtained
samples were characterized by using X-ray diffraction (XRD), fourier transform infrared spectra (FTIR), transmission electron
microscope (TEM), UV-Vis diffuse reflectance spectra (DRS), and thermal analysis. The measured results indicate that CdS species
in the composites exist in the form of pillars and nanoparticles, the crystallized CdS particles are in the hexagonal symmetry.
The photocatalytic activities of the pillared nanocomposite were enhanced significantly comparing with the bare rectorite
and the pure CdS. Moreover, the photostabilities of the obtained nanocomposites are also better than that of the pure CdS
due to the hosts retard the photocorrosion of the CdS. 相似文献
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Further Information of the Associated Li Deposits in the No.6 Coal Seam at Jungar Coalfield,Inner Mongolia,Northern China 总被引：2，自引：0，他引：2
SUN Yuzhuang ZHAO Cunliang LI Yanheng WANG Jinxi ZHANG Jiany JIN Zhe LIN Mingyue Wolfgang KALKREUTH 《《地质学报》英文版》2013,87(4):1097-1108
Total 138 coal samples and 14 parting samples were taken from the No. 6 Seam of the Jungar Coalfield, Inner Mongolia. These samples were analysed by optical microscopy, sequential chemical extraction procedure (SCEP), inductively coupled plasma mass spectrometry (ICP-MS), X-ray powder diffraction (XRD), and scanning electron microscope in conjunction with an energy-dispersive X-ray spectrometer (SEM-EDX) analysis. The results indicate that the Li contents have reached the industrial grade of the coal associated Li deposit, and the total Li reserves have reached 2406600 tons, that is, 5157000 tons Li2O in the No. 6 seam in the Jungar Coalfield. The sequential chemical extraction procedure results suggest that the Li concentration is mainly related to inorganic matter. The minerals in the coals consist of kaolinite, boehmite, chlorite-group mineral, quartz, calcite, pyrite, siderite and amorphous clay material. Some Li could be absorbed by clay minerals in the Li-bearing coal seam. The chlorite phase?could be?most likely the host for a part of Li. The Yinshan Oldland should be the most possible source of Li of the coal. 相似文献
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贵州燃煤型地方性砷中毒地区煤的矿物组成 总被引：4，自引：0，他引：4
采用低温灰化（LTA）和X衍射粉晶分析（XRD）,结合带X光能谱的扫描电子显微镜（SEM—EDX）等方法研究了贵州燃煤型地方性砷中毒地区煤的矿物组成,计算了各矿物的相对含量,初步探讨了煤中主要的含砷矿物。 相似文献
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Ana L.Duarte Kátia DaBoit Marcos L.S.Oliveira Elba C.Teixeira Ismael L.Schneider Luis F.O.Silva 《地学前缘(英文版)》2019,10(3):927-939
In Brazil, intense coal exploitation activities have led to environmental deterioration, including soil mortification, water contamination, loss of ecosystem, and atmospheric contamination. In addition,considerable quantities of sulfur-rich residues are left behind in the mining area; these residues pose grave environmental issues as they undergo sulfide oxidation reactions. When sulfur oxides come in contact with water, extreme acid leachate is produced with great proportions of sulfate, and hazardous elements(HEs), which are identified as coal drainage(CMD). CMD is an environmental pollution challenge, particularly in countries with historic or active coal mines. To prevent CMD formation or its migration, the source must be controlled; however, this may not be feasible at many locations. In such scenarios, the mine water should be collected, treated, and discharged. In this study, data from 2005 to2010 was gathered on the geochemistry of 11 CMD discharges from ten different mines. There are several concerns and questions on the formation of nanominerals in mine acid drainage and on their reactions and interfaces. The detailed mineralogical and geochemical data presented in this paper were derived from previous studies on the coal mine areas in Brazil. Oxyhydroxides, sulfates, and nanoparticles in these areas possibly go through structural transformations depending on their size and formation conditions. The geochemistry of Fe-precipitates(such as jarosite, goethite, and hematite) existent in the CMD-generating coal areas and those that could be considered as a potential source of hazardous elements(HEs)(e.g., Cr) were also studied because these precipitates are relatively stable in extremely low pH conditions. To simplify and improve poorly ordered iron, strontium, and aluminum phase characterization, field emission scanning electron microscopy(FE-SEM), high-resolution transmission electron microscopy(HR-TEM), micro-Raman spectroscopy, and X-ray diffraction(XRD) and sequential extraction(SE) studies were executed on a set CMD samples from the Brazilian mines. This study aimed to investigate the role of both nanomineral and amorphous phase distribution throughout the reactive coal cleaning rejects profile and HEs removal from the water mine to provide holistic insights on the ecological risks posed by HEs, nanominerals, amorphous phases, and to assess sediments in complex environments such as estuaries. 相似文献
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鄂尔多斯盆地东北缘准格尔煤田煤中超常富集勃姆石的发现 总被引：10，自引：0，他引：10
运用X射线衍射分析(XRD)、带能谱仪的扫描电镜(SEM-EDX)和光学显微镜等技术,首次在鄂尔多斯盆地东北缘准格尔矿区6号巨厚煤层中发现了超常富集的勃姆石及其特殊的矿物组合,勃姆石含量可高达13.1%,与勃姆石伴生的矿物有磷锶铝石、锆石、金红石、菱铁矿、方铅矿、硒铅矿和硒方铅矿。重矿物的组合特征与华北地区本溪组铝土矿中的重矿物组合特征相似,高含量的勃姆石主要来源于聚煤盆地北偏东方向本溪组风化壳铝土矿,三水铝石以胶体溶液的形式从铝土矿中被短距离带入泥炭沼泽中,在泥炭聚积阶段和成岩作用早期经压实作用脱水凝聚而形成勃姆石。 相似文献
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P. K. Mukhopadhyay G. Lajeunesse A. L. Crandlemire 《International Journal of Coal Geology》1996,32(1-4)
Systematic changes in mineralogy, enrichment and depletion of selected elements, and mineralogical speciation of selected elements in fly ash and bottom ash samples from the Lingan Power Plant were compared to run-of-mine and pulverized feed coal from the Sydney coalfield, Nova Scotia, eastern Canada. The analytical techniques used were an electron microprobe equipped with energy and wavelength X-ray dispersive spectrometers, X-ray diffraction, neutron activation, scanning electron microscopy with energy dispersive X-ray and incident light petrography. Three types of glasses (Fe/O-rich, Fe/Al/Si/O-rich and or Al/Si/O-rich) were identified in the combustion residues; they were formed as a result of the interaction of melted pyrite and clay minerals. Compared to the feed coal, most elements were enriched 10 to20 times in the fly ash. The concentration of the elements in both the fly ash and bottom ash are comparable to coal ash that is generated by the low temperature asher in the laboratory. Some chalcophile elements such as arsenic and lead occurred as a solid solution in pyrite in the feed coal and were concentrated in the float fraction (density: <2.81 g/cm3) of the fly ash with non-crystalline Fe-oxides. X-ray mapping of arsenic in the fly ash and bottom ash indicates that arsenic was evenly distributed as oxide within the Fe/O- and Fe/Al/Si/O-rich glass and crystalline phases in the fly ash, possibly in solid solution. Arsenic is associated with Fe/O and Fe/S crystalline phases in the bottom ash. 相似文献