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1.
Mineralogy, physical characterization and magnetic separation performance were investigated for purification of a raw ilmenite concentrate. With the aid of mineral liberation analyzer (MLA) and optical microscope, it was found that (1) most of heavy minerals were distributed in the narrow size fraction, (2) clays and Ti-bearing magnetite needed to be separated prior to magnetic separation, (3) harmful elements such as Ca, P, 232Th and except Mg would’t be enriched in ilmenite concentrate, but enrichment of Mg could’t affect the concentrate quality, (4) Monazite was the main carrier mineral of Th, Ca and P. In addition, the expected yield of rejection and theoretical magnetic inductions were determined by separation tests of heavy minerals and magnetic analysis, respectively. Both the wet and dry magnetic separations were performed focusing on the examination of magnetic induction and it was found that the dry separator has an excellent selectivity against radionuclide bearing minerals. Finally, the dry magnetic separation as a core process technology was proposed to purify the raw concentrate.  相似文献   
2.
Polymetallic ores always contain precious rare metals which have high economic value. There is a large-scale copper (Cu)–zinc (Zn)–stannum (Sn) polymetallic ore deposit in Dulong, Yunnan Province, China. The polymetallic ore deposit contains a lot of silver (Ag) and indium (In). In this paper, the polymetallic ore is investigated to explore the characteristics of its process mineralogy by X-ray diffraction (XRD), X-ray fluorescence (XRF), optical microscopy (OM), and electron probe micro-analyser (EMPA). The contents of the main valuable elements in the ore are Cu 0.20%, Zn 3.93%, Sn 0.47%, Fe 22.70% and S 9.90%. Cu, Zn, Sn, and Fe mainly occur in chalcopyrite, marmatite, cassiterite and magnetite, respectively. In addition, as rare metal elements, there are also Ag 4.9 g/t and In 90.50 g/t in the ore. Ag mainly occurs in matildite and an unknown mineral (Ag0.75(Zn, Fe)0.25S) and these two minerals are all enclosed and disseminated in marmatite. In does not form an independent mineral, but an isomorphism element which mainly occurs in marmatite. Based on the results of the process mineralogy and actual conditions, a feasible flowsheet for this polymetallic ore is designed and optimized. The industrial experimental results show that processing capacity of the plant and the indexes of the concentrates are improved.  相似文献   
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This paper proposes a new technique for preparation of high-grade titanium slag from Panzhihua vanadium titanomagnetite concentrate by reduction–melting–magnetic separation processing. Chemical analysis, x-ray diffraction, and scanning electron microscopy in conjunction with energy-dispersive spectroscopy were used to characterize the samples. The effective separation of iron and titanium slag could be realized by melting metallized pellets at 1550°C for 60 min with the addition of 1% CaO (basicity of 1.1) and 2% graphite powder. The small iron particles embedded in the slag could be removed by fine grinding and magnetic separation process. The grade of TiO2 in the obtained high-grade titanium slag reached 60.68% and the total recovery of TiO2 was 91.25%, which could be directly applied for producing titanium white by the sulfuric acid process. This technique provides an alternative method to use vanadium titanomagnetite concentrate of the Panzhihua area in China.  相似文献   
6.
裴旭  施昆  曾政祥 《工程勘察》2015,(5):49-54,68
机载激光雷达测量系统受到多种误差源的影响,其系统由GPS接收机、激光测量单元系统(IMU)、激光测距仪等组合而成,所以可以将误差来源分为单机误差和集成误差两部分。本文主要对集成误差中影响较大的安置角误差作了分析,定性和定量地分析了安置角误差对激光脚点坐标的影响。同时,描述了一种安置角检校方法,并用算例详述了检校场选取与航线设计以及安置角检校步骤,对其作了精度评定,分析了误差原因。  相似文献   
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根据拉格朗日原理提出了线性模型的总体最小二乘新算法。通过重构矩阵运算推导了算法的迭代公式,该算法推导过程简单且易于程序实现。通过实例分析并与几种总体最小二乘解算方法相比较,结果表明,该文算法正确合理。  相似文献   
8.
晏玲 《软件》2020,(2):218-223
针对重曝光过程中欠曝光像素点对周围像素点产生干扰,导致高动态范围(High dynamic range,HDR)图像产生伪影的现象,提出顾及欠曝光的亮度映射HDR图像生成方法。具体步骤为:(1)欠曝光分类。利用L2正则化逻辑非线性回归算法训练出欠曝光像素点的分类器。(2)对图像进行重曝光。非欠曝光区域使用线性拟合得到的亮度映射函数重新曝光,欠曝光区域利用长曝光区域进行补偿。(3)生成HDR图像。利用重曝光后图像的饱和度,对比度,曝光度和亮度信息生成权重图,再加权融合生成HDR图像。实验表明,该方法有效抑制合成图像的伪影,与已有方法相比,在清晰度、颜色协调性、边缘保持以及运行时间上都有较大提高。  相似文献   
9.
云南曲靖盆地地下水脆弱性模糊评价   总被引:2,自引:0,他引:2       下载免费PDF全文
在DRASTIC指标的基础上,运用层次分析法构建了云南省曲靖盆地地下水脆弱性指标体系,并采用多级二层模糊评价方法进行脆弱性评价。结果表明:曲靖盆地地下水脆弱性分区为四级,西部基岩地下水和孔隙水脆弱性高,东部的孔隙水及少量岩溶水处于脆弱性中等。评价结果有利于地下水环境的保护。  相似文献   
10.
A new synthetic reagent DPTUHP [diphenyl α-(3-phenylthioureido) hexylpbosphonate] containing a hydrocarbon chain nonpolar group, a thioureido, and a phosphonate easter chelating group, has proven to be an effective collector for the flotation of cerussite mineral. The synthetic method utilized the Mannich-type reaction of an N-monosubstituted thiourea, an aldehyde, and triphenyl phosphate in glacial acetic acid solution. The experimental results of flotation of the cerussite mineral show that the collector has stronger collecting ability and higher selectivity in a neutral and a slightly alkaline medium, especially in the pulp of pH=8. Using the measurements by infrared spectroscopy (IR) and X-ray photoelectron spectroscopy (XPS) of the cerussite mineral, the collector, as well as the cerussite treated with the collector, the flotation mechanism of cerussite has been discussed. It is concluded that the adsorption of collector on cerussite is a chemical adsorption through the electron donor atoms of the collector chelating the Pb ( Ⅱ ) of cerussite to form chelate.  相似文献   
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