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铜 基 催 化 剂 上 甲 醇 水 蒸 汽 重 整 制 氢Ⅰ. 催 化 剂 组 成 的 影 响  [PDF]
赵 宁,尹燕华,王新喜,牛成德
分子催化 , 2009,
Abstract: 在 H2 O / CH3 OH 摩 尔 比 为 1. 3、 液 空 速 为 1. 5 h- 1 、 反 应 温 度 为 220 ℃ 条 件 下 , 对 甲 醇 水 蒸 汽 重 整 制 氢 Cu /Zn / ( Fe, Mn, Cr) / AlO 催 化 剂 性 能 进 行 了 考 察 . 研 究 表 明 , Cr 的 加 入 可 以 显 著 提 高 甲 醇 的 转 化 率 , 降 低 出 口 气 体中 的 CO 含 量 . 与 Cu60 Zn30 Al10 催 化 剂 相 比 , Cu30 Zn15 Cr45 Al10 催 化 剂 出 口 气 体 中 CO 的 含 量 降 低 54% , 甲 醇 的 转 化 率 提 高 约 20% .
Petrology and P-T condition of white mica-chlorite schists from Vlasina series - Surdulica, SE Serbia
Vaskovi? Nada J.
Geolo?ki Anali Balkanskog Poluostrva , 2002, DOI: 10.2298/gabp0264199v
Abstract: This paper reports structural, textural, petrological and metamorphic data from Vlasina Series of greenschists rocks (as part of the Upper Complex of the Serbo-Macedonian Massif) within which group of white mica-chlorite schist are extensively developed. This group of rocks made the ground of series in which various types of green rocks appear as a lenses and small irregular mass, rarely as dykes. Other features, that characterize these rocks, are the common occurrence of albite and garnet (subordinate) porphyroblasts, as well as development of quartz segregation. Group of white mica-chlorite schist makes about 75 vol. % of Series. Among them, according to mode and mineral composition, the following schist varieties are distinguished: albite-white mica-chlorite (±garnet), white mica-chlorite (±garnet), albite-white mica, sericite-chlorite (±albite), graphite-sericite as well as phyllites and calcshists. Their metamorphic evolution is characterized by the development of a metamorphic episode during Carboniferous - c. 350-330 Ma (Milovanovi et al., 1988) of low to medium P and T. The mineral assemblages of first phase (low PT) is preserved as a very thin Si=S1 foliation included in albite porphyroblast or as small polygonal arcs of S1 in S2 foliation. Textural, mineralogical and petrological data indicate that original volcanoclastic-sedimentary series was transformed during three phase of deformation and metamorphism in the temperature range from 320-415°C, locally 450-500°C and pressures 3 to 5 kbar.
Mineralogical and Geochemical Characterization of Gold Bearing Quartz Veins and Soils in Parts of Maru Schist Belt Area, Northwestern Nigeria  [PDF]
Samson Adeleke Oke,Akinlolu Festus Abimbola,Dieter Rammlmair
Journal of Geological Research , 2014, DOI: 10.1155/2014/314214
Abstract: Epigenetic, N-S, NNE-SSW quartz veins crosscut metapelites and metagabbro in Maru area. The objectives of this work were to study field, mineralogy, and geochemical characteristics of gold bearing quartz veins and soils. Euhedral and polygonal magnetite with hematite constituted the major ore minerals. Quartz occurred as main gangue phase with appreciable sericite and chlorite. The mineralogy of soil retrieved from twelve minor gold fields examined with X-ray diffraction is quartz ± albite ± microcline ± muscovite ± hornblende ± magnetite ± illite ± kaolinite ± halloysite ± smectite ± goethite ± vermiculite ± chlorite. The concentration of gold in quartz vein varies from 10.0 to 6280.0?ppb with appreciable Pb (3.5–157.0?ppm) and ΣREE (3.6 to 82.9?ppm). Gold content in soil varies from < to 5700.0?ppb. The soil is characterized by As ± Sb gold’s pathfinder geochemical association. Multidata set analysis revealed most favourable areas for gold. Possibility of magmatic fluids as part of ore constituents is feasible due to presence of several intrusions close to quartz veins. Based on field, mineralogical, and geochemical evidences, ore fluids may have been derived from fracturing, metamorphic dewatering, crustal devolatilization of sedimentary, gabbroic protoliths, and emplaced in an orogenic setting. 1. Introduction Precambrian rocks within and around Maru Schist belt host some quartz veins that are gold bearing. The gold deposits were heavily mined during the colonial era approximately before 1960 and after that period by artisanal miners. General descriptive information on gold mineralization in Maru schist belt has been documented [1–3]. Gold occurs primarily in quartz veins and as placers in soil (eluvial) and stream sediments (alluvial). The quartz veins containing gold occur in association with metamorphosed rocks ranging in composition from semipelitic to pelitic and mafic. Primary gold mineralization produced chemical signature in the overburden and surrounding soil probably through weathering processes. Weathering processes provide samples (soils and stream sediments) that yield data on local hidden mineralization or on the potential existence of major or minor mineralization in a wide region. The residual soil is the geochemical sample that is often used to detect the location of hidden mineralization once a zone of economic interest is localized [4]. Migration of groundwater provided chemical response at the surface. This process produces elemental dispersion pattern [5]. Most of these dispersed elements (e.g., Cu, Ag, Zn, Cd, As, Bi, Pb, Sb,
Coesite in the eclogite and schist of the Atantayi Valley, southwestern Tianshan, China
Zeng Lü,LiFei Zhang
Chinese Science Bulletin , 2012, DOI: 10.1007/s11434-012-4979-4
Abstract: Coesite is an indicator mineral of ultra-high-pressure metamorphism. Since coesite was reported in the Habutengsu Valley, we have also found it in eclogite and schist from the Atantayi Valley in the southwestern Tianshan, China. Petrographic and micro-Raman analyses were carried out for the Atantayi metamorphic rocks and coesite was recognized in the predominant rock types, i.e. schist and eclogite, from three sections. The coesite-bearing schist consists mainly of garnet, Na-Ca amphibole, quartz, white mica and albite; the coesite-bearing eclogite is mainly composed of omphacite, garnet, glaucophane and zoisite. The coesite occurs as various mineral inclusions within porphyroblastic garnet. Findings of coesite in eclogite and associated schist indicate not only the regional in situ formation of the Atantayi ultra-high-pressure eclogite, but also the large areal extent of ultra-high-pressure metamorphism in southwestern Tianshan, extending up to 10 km north-south and 60–80 km east-west.
响叶杨(populusadenopoda)种子的形成及其寿命  [PDF]
南京林业大学学报(自然科学版) , 1984, DOI: 10.3969/j.jssn.1000-2006.1984.01.014
Abstract: <正>用显微技术及软x射线摄影,定位观察响叶杨种子发育过程中的形态变化与胚胎发育的对应关系。根据观察、试验的结果,讨论了环境条件与种子寿命的关系;还测定了响叶杨种子寿命的变化规律及其影响因素,探索延长这种子寿命的方法。
动物学研究 , 1995,
Abstract: 1994年10月15日马中翼等人在云南省泸水县的老窝捕获到1只雄鸟,经中国科学院昆明动物研究所鉴定为黄腰响蜜lie,为我国鸟类科的新记录。标本保存在中国科学院昆明动物研究所鸟类标本室。科的特征体形较小。嘴形似雀,短而粗实,上嘴稍弯曲;尾羽12枚;翅形长而尖,仅具9枚初级飞羽;脚呈对趾型,第2、3趾向前,第1、4趾向后,似啄木鸟。
响蜜lie科的新记录  [PDF]
动物学研究 , 1995,
Abstract: 1994年10月15日马中翼等人在云南省泸水县的老窝捕获到1只雄鸟,经中国科学院昆明动物研究所鉴定为黄腰响蜜lie,为我国鸟类科的新记录。标本保存在中国科学院昆明动物研究所鸟类标本室。科的特征体形较小。嘴形似雀,短而粗实,上嘴稍弯曲;尾羽12枚;翅形长而尖,仅具9枚初级飞羽;脚呈对趾型,第2、3趾向前,第1、4趾向后,似啄木鸟。
不同基质对“珍珠”南瓜叶绿素及NR 和 POD 活 性 的 影 响  [PDF]
武英霞,沈 军,杨和连,李新峥,刘振威
北方园艺 , 2010,
不 同 种 植 密 度 对 蕨 麻 块 根 的 影 响  [PDF]
马国良1,沈宁东1,李军乔2,李 宁1,汤青川1,韦梅琴1
北方园艺 , 2010, DOI: 10.11937/bfyy.201017087
温 度 对 设 施 桃 花 器 官 发 育 的 影 响  [PDF]
北方园艺 , 2010, DOI: 10.11937/bfyy.201020033
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