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71.
通过对双王金矿床8号矿体厚度、品位的统计分析,以及对矿化强度指数的计算,试从勘探角度探讨矿体在走向上和垂向上的矿化规律,对于加深认识双王金矿床成矿规律有重要的理论意义,同时对指导该区找矿勘探有重要的实际意义。  相似文献   
72.
Chemical treatment was performed to modify the surfaces of the TiO2-based (TOB) film containing P for improving its bioactivity. The apatite-forming ability of the chemically treated TOB (C-TOB) film was enhanced due to the formation of hydroxyl-functionalized surface during the SBF immersion process. However, further heat treatment of the C-TOB films formed crystalline sodium titanate, showing poor ability to release Na+ ions, which does not facilitate the formation of hydroxyl-functionalized surface, thus lowering the apatite-forming ability. Firstly, amorphous Ca- and P-containing precipitates formed during the SBF immersion process, eventually transformed to crystalline biomimetic apatite, exhibiting a porous structure on two-scales of micron and nanometer levels. The preliminary cell experiment showed that the C-TOB film has good biocompatibility.  相似文献   
73.
Hualin Zhang 《Materials Letters》2009,63(27):2313-2316
Biomimetic mineralization is an effective method to improve the biocompatibility and bone inductivity of certain materials. In this study, composite scaffolds composed of poly(lactic-co-glycolic acid) (PLGA) and multi-walled carbon nanotubes (MWNTs) were prepared by electrospinning. Subsequently, the scaffolds were immersed in a simulated body fluid (1.5 × SBF) at 37 °C for 7, 14 and 21 days for biomimetic mineralization. Scanning electron microscopy, Raman spectroscopy, and X-ray diffraction were used for characterization. It was found that the electrospun scaffolds had extremely resemblant structural morphology to the natural extracellular matrix. After mineralization, apatite crystals were deposited on the PLGA/MWNTs composite scaffolds. The mineralized PLGA/MWNTs composites may be potentially useful in tissue engineering applications, particularly as scaffolds for bone tissue regeneration.  相似文献   
74.
Bioavailability of chlorobenzenes (CBs) in soils to microbial populations has implications for remediation of waste sites with long histories of contamination. Bioavailability of CB was assessed using mineralization assays for two types of wetland soils with contrasting properties. The rate and extent of CB mineralization were greater than predicted by mathematical models which assume instantaneous desorption followed by biodegradation. The freshly added CB was degraded with initial mineralization rates (IMRs) of 0.14microgL(-1)h(-1) and 1.92microgL(-1)h(-1) for marsh soil and wetland soil respectively. These values indicate that CB-degrading bacteria had an access to the sorbed CB. Mineralization assays were also performed for wetland soils after the CB was aged for 1, 7 and 31 days. The results revealed that even a desorption-resistant part of the sorbed CB was degraded although the degradation occurred at lower rates and to a lesser extent.  相似文献   
75.
红石泉铀矿床矿化特征及成因类型探讨   总被引:2,自引:1,他引:1       下载免费PDF全文
红石泉铀矿床位于古元古代基底褶皱带内侵入到龙首山群上部地层中的伟晶状钾质花岗岩中,矿床中铀的存在形式主要为晶质铀矿,其次为沥青铀矿、残余铀黑。通过化学全分析及相关矩阵分析得出,与铀正相关性较大的有P2O5、TiO2、MgO、Fe2O3、MnO、T失。采用三阶段规模式方法得出成矿年代复相关系数为0.9999,表明成矿与成岩时代接近,属于吕梁运动时期产物。黑云母化阶段是主要的矿化阶段,黑云母中能见到附生锆石包裹体及流线状的包裹体,结合成岩阶段(混合岩化主期)和黑云母化以后的矿化阶段,矿床成因应为与混合岩化有关的多阶段交代热液矿床,从矿床的形成过程可以看出,铀的来源主要由深部熔浆和钾硅质溶液带来。  相似文献   
76.
冠醚液晶具有液晶的有序性和冠醚络合金属离子的特性,采用单臂冠醚液晶成功地用粒模拟生物膜的离子传输,首次提出了冠醚液晶和PVC的二元复合膜,这种新的仿生膜模型种巧妙地模拟生物膜的温控传输,能更充分发挥膜传输中液晶的基本功能。因此,提出了冠醚液晶分子在液晶志时能自组装成离子通道传输离子。  相似文献   
77.
阳山金矿泥山矿段与花岗岩类有关的金矿化是该矿段重要的金矿化类型,通过对斜长花岗斑岩脉及其矿体的研究,探讨此类金矿的基本特征,得出该矿化类型受控于燕山期花岗岩体。区内岩体的分布与构造关系密切,并受断裂的控制,岩脉走向呈近EW向,产出规模一般较小,多呈脉状产出,少量为岩株。岩石类型为中酸性岩,岩性主要为斜长花岗斑岩。通过对斜长花岗斑岩脉的矿化蚀变特征及含金性进行分析研究,认为泥山矿段508号脉成矿过程为含矿物质迁移、富集过程。  相似文献   
78.
The center of excellence (COE) titled ‘The Creation of Nature-Guided Materials Processing’ has been established in Nagoya University as the 21st Century COE Program supported by Ministry of Education, Culture, Sports, Science and Technology. In the Nature COE, various activities on the education and research are being performed through learning the laws of nature, namely, methods of attaining ‘appearance of the maximum function under the minimum substance and energy consumption’, which the nature and living organisms have acquired through their evolution in long period. Together with such educational programs for PhD students as research incentive, oversea training, and external evaluation programs, an ‘Open-Cluster Program’ was originated for promoting researches proposed by research groups consisting of young researchers in and out of the university and also for fostering them.

The researches are being advanced on materials used for living bodies, mimicking structures which nature or living bodies are forming, and producing materials by mimicking processes to form the structures observed in the nature or the living bodies. In this COE, these researches are conducted by four groups to extend the processes observed in the natural world to a new type of processing, that is, thoroughly examined and rationalized by plunging a scalpel of engineering and to establish a new academic field of materials science and engineering.  相似文献   
79.
The decolourization and mineralization of a solution of an azo dye using a catalyst based on Fe(II) supported on Y Zeolite (Fe(II)-Y Zeolite) and adding hydrogen peroxide (heterogeneous Fenton process) have been studied. The catalyst was prepared by ion exchange, starting from a commercial ultra-stable Y Zeolite. All experiments were performed on a laboratory scale set-up. The effects of different parameters such as initial concentration of the dye, initial pH of the solution of the dye, H(2)O(2) concentration, temperature and ratio of amount of catalyst by amount of solution on the decolourization efficiency of the process were investigated. A percentage of colour removal of 99.3±0.2% and a mineralization degree of 84±5% of the solution of the dye were achieved in only 6 min of contact time between the catalyst and the solution, under the following conditions: initial concentration of the dye of 50 ppm, pH 5.96, 8.7 mM of H(2)O(2), T of 80°C and catalyst concentration of 15 g/L. Moreover, the catalyst Fe(II)-Y Zeolite can be easily filtered from the solution, does not leach any iron into the solution (avoiding any secondary contamination due to the metal) and its effectivity can be reproduced after consecutive experiments.  相似文献   
80.
王彦君 《矿冶》2020,29(4):23-28
通过对紫金山东南矿段铜钼(金)矿床地质矿化特征分析,指出铜钼矿化带主要赋存于花岗闪长斑岩的内外接触带,处于似斑状花岗闪长斑岩的上部,金矿化带赋存在表生氧化带的英安玢岩、隐爆角砾岩中。经过对矿石的组构特征、矿物生成顺序等特征分析,将矿床的成矿演化过程分为斑岩热液期、高硫化浅成低温热液期、表生氧化期三个主要矿化期次,进一步将斑岩热液期分为黑云母-钾长石化阶段、石英-绢云母化阶段、碳酸盐化阶段三个阶段;高硫化浅成低温热液期分为地开石化阶段、明矾石化阶段、硅化阶段三个阶段。研究结果为进一步研究矿床成因提供了依据。  相似文献   
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