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31.
32.
对近年来国内外盐湖资源开发利用的进展情况加以介绍 ,也涉及到国外钾、锂、镁、硼、碘等相关产品的生产、消费、价格等情况。还对资源开发的可持续发展以及我国盐湖及相关资源开发的某些问题加以讨论。 相似文献
33.
青海盐湖锂资源开发现状及对提锂产业发展建议 总被引:4,自引:4,他引:0
中国正处在环境污染治理和产业结构调整的关键时期,发展新能源产业是应对能源和环境危机的必然选择;同时,锂资源储备和提锂技术直接影响到国家能源战略安全。中国科学院青海盐湖所经过二十年开发,目前已形成一套成熟的选择性离子迁移分离提锂技术,并经过了产业化和工业应用验证,核心技术达到国际领先水平。该产业化具有绿色、高效、低能耗、低物耗、低产品成本、高纯度等特点,技术通用性好,可推广应用到青海、西藏高海拔生态脆弱地区以及南美玻利维亚、阿根廷、智利等高镁锂比盐湖中锂的分离提取,在高钙镁地热水、油(气)田水提锂方面也有一定的应用潜力。 相似文献
34.
Hamdy H. Abd El-Naby 《Mineralium Deposita》2008,43(8):933-944
Uranium mineralization in the El Erediya area, Egyptian Eastern Desert, has been affected by both high temperature and low
temperature fluids. Mineralization is structurally controlled and is associated with jasperoid veins that are hosted by a
granitic pluton. This granite exhibits extensive alteration, including silicification, argillization, sericitization, chloritization,
carbonatization, and hematization. The primary uranium mineral is pitchblende, whereas uranpyrochlore, uranophane, kasolite,
and an unidentified hydrated uranium niobate mineral are the most abundant secondary uranium minerals. Uranpyrochlore and
the unidentified hydrated uranium niobate mineral are interpreted as alteration products of petscheckite. The chemical formula
of the uranpyrochlore based upon the Electron Probe Micro Analyzer (EPMA) is . It is characterized by a relatively high Zr content (average ZrO2 = 6.6 wt%). The average composition of the unidentified hydrated uranium niobate mineral is , where U and Nb represent the dominant cations in the U and Nb site, respectively. Uranophane is the dominant U6+ silicate phase in oxidized zones of the jasperoid veins. Kasolite is less abundant than uranophane and contains major U,
Pb, and Si but only minor Ca, Fe, P, and Zr. A two-stage metallogenetic model is proposed for the alteration processes and
uranium mineralization at El Erediya. The primary uranium minerals were formed during the first stage of the hydrothermal
activity that formed jasperoid veins in El Eradiya granite (130–160 Ma). This stage is related to the Late Jurassic–Early
Cretaceous phase of the final Pan-African tectono-thermal event in Egypt. After initial formation of El Erediya jasperoid
veins, a late stage of hydrothermal alteration includes argillization, dissolution of iron-bearing sulfide minerals, formation
of iron-oxy hydroxides, and corrosion of primary uranium minerals, resulting in enrichment of U, Ca, Pb, Zr, and Si. During
this stage, petscheckite was altered to uranpyrochlore and oxy-petscheckite. Uranium was likely transported as uranyl carbonate
and uranyl fluoride complexes. With change of temperature and pH, these complexes became unstable and combined with silica,
calcium, and lead to form uranophane and kasolite. Finally, at a later stage of low-temperature supergene alteration, oxy-petscheckite
was altered to an unidentified hydrated uranium niobate mineral by removal of Fe. 相似文献
35.
用二氧化锰做吸附剂,进行了吸附法盐湖卤水提锂工艺试验,取得了全流程工艺操作条件和技术数据,可做为更大规模试验设计和操作依据。 相似文献
36.
37.
Distinguishing between natural and aquaculture-derived sediment concentrations of heavy metals in the Broughton Archipelago, British Columbia 总被引:5,自引:0,他引:5
Marine sediment samples were collected in the Broughton Archipelago, British Columbia, to assess the use of a geochemical normalization technique in the identification of a chemical tracer of aquaculture waste material. Zinc and copper were suggested as tracers of feed pellets, while copper was considered an indicator of anti-foulant agents used on netpen systems. The sediment samples were analyzed for carbon, nitrogen, organic matter, water, trace-element, and free sulfide concentrations, and sediment grain-size distribution. Sediment texture analysis revealed a wide range of substrate types from sand to silty loam categories. Strong relationships between sediment texture, sediment porosity, and organic content were observed across both near-field and far-field stations. Excess zinc and copper sediment concentrations, identified using a lithium-normalization technique, were restricted to near-field sampling stations (0 and 30m from netpen systems). The relationships between these metal tracers and organic content and sulfur concentrations were explored to account for variations in sediment concentrations of zinc and copper. 相似文献
38.
青藏高原是我国富 L i盐湖的主要分布区域 ,这些富 L i盐湖主要分布在柴达木盆地中部和西藏的中、西部地区。北部柴达木盆地盐湖 L i的储量大、Mg/ L i比值高、卤水 L i含量较高 ,南部西藏盐湖 L i的储量较大、Mg/L i比值低 ,L i含量很高。青藏高原富 L i盐湖主要分布在氯化物型—硫酸盐型过渡区内 ,其 L i含量在 12 0~ 2 6 0 m g/L之间 ;西藏富 L i盐湖主要分布在碳酸盐型—硫酸盐型过渡区内 ,其 L i含量在 2 5 0~ 6 6 0 m g/ L之间。在西藏各类盐湖中碳酸盐型盐湖含 L i较低 ,这很可能与其参加到早期沉淀的碳酸盐矿物晶格中有关。盐湖卤水中 L i的空间分布与其水源补给方向和蒸发环境紧密相关。Mg/ L i比值研究表明 ,盐湖中 Mg和 L i的含量成反比关系 ,即高 Mg环境不利于 L i的富集 相似文献
39.
40.