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991.
De‐Feng Shen Shan‐Shan Wu Rui‐Rui Wang Qiang Zhang Zhong‐Juan Ren Hong Liu Hua‐Dong Guo Guang‐Gang Gao 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(44):6153-6159
A structure‐determined silver nanocluster of [Ag10(Eth)4(CF3COO)6(CH3OH)3]·3CH3OH (Eth = ethisterone) ( 1 ), is firstly demonstrated by self‐assembly of silver salt and ethisterone. Due to the thiophilicity of silver(I) ions, complex 1 shows reactivity with glutathione (GSH) molecules in solution and induces the fluorescence quenching behavior. Thus, complex 1 can be used as a fluorescent sensor for GSH. In consideration of the higher level of GSH in cancerous cells, complex 1 presents significant tumor suppression reactivity toward the human hepatocellular carcinoma (HepG2) cells with IC50 value of 165 × 10?9 m . Especially, complex 1 displays 3.4‐fold higher in vitro cytotoxicity to HepG2 cells than that of the normal CCC‐HEL‐1 cells, which makes complex 1 a potential targeting suppression agent for cancerous cells. The molecular design of complex 1 not only generates a new medicine‐silver(I) cluster family, but also opens a new avenue to the targeting anticancer organosilver(I) materials. 相似文献
992.
993.
Perovskite Solar Cells: Moth‐Eye TiO2 Layer for Improving Light Harvesting Efficiency in Perovskite Solar Cells (Small 18/2016)
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994.
采用金属有机化合物气相外延技术(MOCVD),在Ge衬底上生长Ga_xIn_(1-x)P外延层,探究不同生长温度对Ga_xIn_(1-x)P材料的无序生长特性的影响。为探究无序度随温度的变化规律,使用X射线衍射仪(XRD)与光致发光测试仪(PL)对外延材料进行测试,并修正由Ga_xIn_(1-x)P材料组分改变引起的带隙偏移。最终根据实验现象,对实际生产中的GaInP/GaInAs/Ge三结太阳能电池进行调试,通过提高Ga_xIn_(1-x)P材料的无序度,电池的Voc提高了34mV,转换效率提升0.5%。 相似文献
995.
Mohammad Taherdangkoo Mohammad Hadi Bagheri 《Engineering Applications of Artificial Intelligence》2013,26(5-6):1493-1502
One of the simple techniques for Data Clustering is based on Fuzzy C-means (FCM) clustering which describes the belongingness of each data to a cluster by a fuzzy membership function instead of a crisp value. However, the results of fuzzy clustering depend highly on the initial state selection and there is also a high risk for getting the best results when the datasets are large. In this paper, we present a hybrid algorithm based on FCM and modified stem cells algorithms, we called it SC-FCM algorithm, for optimum clustering of a dataset into K clusters. The experimental results obtained by using the new algorithm on different well-known datasets compared with those obtained by K-means algorithm, FCM, Genetic Algorithm (GA), Particle Swarm Optimization (PSO), Ant Colony Optimization (ACO), Artificial Bee Colony (ABC) Algorithm demonstrate the better performance of the new algorithm. 相似文献
996.
997.
研究白细胞图像分类识别中有效的图像分割与特征提取方法,以提高白细胞图像的正确识别率.由于某些白细胞(粒细胞)中颗粒的存在,严重影响细胞核与细胞质区域的正确分割,通过将空间信息与核函数融入模糊C-均值聚类(FCM)算法,提出一种改进的FCM算法.应用该算法对白细胞图像进行分割,并采用数学形态学方法对分割后的图像进行处理,获得了很好的分割效果,解决了粒细胞的质核分割难题.对于细胞的纹理特征提取,通过对局部二值模式(LBP)中阈值参数的模糊化,建立了基于局部模糊模式(LFP)的纹理特征提取算法.运用本文方法进行图像分割和纹理提取,以支持向量机作为分类器,对CellAtlas的100幅白细胞图像进行了分类识别的实验,结果表明白细胞的正确识别率达到93%. 相似文献
998.
999.
Conventional flat plate Proton Exchange Membrane fuel cell (PEMFC) designs have been under investigation for the last five decades with the majority of the research being conducted in fluid dynamics of the reactants, membrane chemistry, thermal characteristics, stacking, and electrical properties. By rigidly adhering to design characteristics and material choices (graphite flow plates and metal end plates), conventional fuel cell designs have become bulky, fastener intense designs that have a high degree of manufacturing and assembly complexity. The department of energy has recognized the need for economical and efficient manufacturing practices to further the market penetration and end user adoption of fuel cells. Therefore this paper analyzes air-breathing PEMFC's from the perspective of reducing manufacturing complexity, assembly complexity, and costs. Areas of complexity like the flow plates, end plates, sealing methods have been reassessed and this paper proposes alternatives to component functions, and the commonly employed materials along with an alternate assembly strategy. Prototypes built using the new design strategy achieved about 90% reduction in weight and number of components while enjoying an 80% reduction in costs. The new prototypes also possess a superior form factor, along with a 10-fold increase in power density as compared to conventional designs. 相似文献
1000.
Ilia Platzman Jan-Willi Janiesch Jovana Matić Joachim P. Spatz 《Israel journal of chemistry》2013,53(9-10):655-669
While the beneficial impact of modifying and/or targeting T lymphocytes is becoming increasingly accepted in the treatment of different diseases, the road towards cell-based immunotherapy is still long and winding. Major challenges that remain include, amongst others, the guidance and exquisite regulation of immune processes ex vivo. In part, this is due to the difficulties of simulating ex vivo the intimate cellular interactions that occur between T cells and antigen-presenting cells (APCs). The fate of T cells is not solely regulated by the presence of certain molecules on the surface of APCs but also by their density and spatial distribution on the micro- and nanometric scale. Moreover, mechanical properties of APCs and force-dependent conformational changes during the formation of an immunological synapse (IS; a highly organized supramolecular complex at the T cell APC interface), play a crucial role in T cell fate regulation. Various different technical means have been developed to create APC substitutes that are able to simulate ex vivo signals originating from naturally occurring APCs. Here, we review the performance of APC surrogates and discuss their contribution to understanding mechanisms underlying the ability of T cells to perform the “intelligent” mission of acquiring, processing and responding to environmental information. 相似文献