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1.
Surface passivation treatment is a widely used strategy to resolve trap-mediated nonradiative recombination toward high-efficiency metal-halide perovskite photovoltaics. However, a lack of passivation with mixture treatment has been investigated, as well as an in-depth understanding of its passivation mechanism. Here, a systematic study on a mixed-salt passivation strategy of formamidinium bromide (FABr) coupled with different F-substituted alkyl lengths of ammonium iodide is demonstrated. It is obtained better device performance with decreasing chain length of the F-substituted alkyl ammonium iodide in the presence of FABr. Moreover, they unraveled a synergistic passivation mechanism of the mixed-salt treatment through surface reconstruction engineering, where FABr dominates the reformation of the perovskite surface via reacting with the excess PbI2. Meanwhile, ammonium iodide passivates the perovskite grain boundaries both on the surface and top perovskite bulk through penetration. This synergistic passivation engineer results in a high-quality perovskite surface with fewer defects and suppressed ion migration, leading to a champion efficiency of 23.5% with mixed-salt treatment. In addition, the introduction of the moisture resisted F-substituted groups presents a more hydrophobic perovskite surface, thus enabling the decorated devices with excellent long-term stability under a high humid atmosphere as well as operational conditions.  相似文献   
2.
The design of highly stable and efficient porous materials is essential for developing breakthrough hydrocarbon separation methods based on physisorption to replace currently used energy-intensive distillation/absorption technologies. Efforts to develop advanced porous materials such as zeolites, coordination frameworks, and organic polymers have met with limited success. Here, a new class of ionic ultramicroporous polymers (IUPs) with high-density inorganic anions and narrowly distributed ultramicroporosity is reported, which are synthesized by a facile free-radical polymerization using branched and amphiphilic ionic compounds as reactive monomers. A covalent and ionic dual-crosslinking strategy is proposed to manipulate the pore structure of amorphous polymers at the ultramicroporous scale. The IUPs exhibit exceptional selectivity (286.1–474.4) for separating acetylene from ethylene along with high thermal and water stability, collaboratively demonstrated by gas adsorption isotherms and experimental breakthrough curves. Modeling studies unveil the specific binding sites for acetylene capture as well as the interconnected ultramicroporosity for size sieving. The porosity-engineering protocol used in this work can also be extended to the design of other ultramicroporous materials for the challenging separation of other key gas constituents.  相似文献   
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为了避免回收单一钕铁硼废料中有价元素带来的操作复杂和资源浪费等问题,本研究采用共沉淀法共沉淀出钕铁硼废料中的有价元素Me(Nd,Pr,Co,Fe),制备可用于生产再生钕铁硼的原料;根据质量守恒和同时平衡原理,采用MATLAB软件建立Me(Nd,Pr,Co,Fe)-OH--NH3热力学模型,绘制lg[Me]-p H曲线模拟共沉淀工艺,并根据模拟结果确立了共沉淀工艺;模拟和实验的结果表明:根据lg[Me]-p H模拟结果可以确立一步共沉淀法的p H:6~10,Fe3+比Fe2+更易于沉淀完全;在上述条件下获得的共沉淀粉末主相均为Nd,Pr,Co,Fe的化合物,且有价元素的百分比含量均大于99.4%;其中,当p H值在8左右时回收率最高,在该条件下金属元素Me(Nd,Pr,Co,Fe)的沉淀效率分别为:98.7%,99.9%,93.6%,99.9%。该结果也表明共沉淀法工艺不仅高效,而且所制备的共沉淀粉末可以满足制备二次钕铁硼的需要。  相似文献   
5.
考察了双河油田双河联、江河联注入水堵塞地层的因素;膨胀性黏土,悬浮固体颗粒。细菌及悬浮污油。含膨胀性黏土的双河南、双河北及不含膨胀性黏土的双江岩心粉,在注入水中相对于地层水中的体积膨胀度分别为14.5%、11.1%及0.02%;注入100PV不含悬浮颗粒的等体积比地层水、注入水混合水使双河、双江岩心渗透率分别下降7%和4%、9%和7%。注入水中悬浮颗粒引起岩心渗透率下降,粒径越大、颗粒浓度越大、注入量越大,则渗透率越低。在粒径2.1μm或颗粒浓度3mg/L前后下降幅度变化较大。注入水中硫酸盐还原菌引起岩心渗透率下降,含菌量越大则渗透率开始下降时的注水量越小,注入含菌50个/L的水100PV使岩心渗透率下降7%。岩心对注水合油量敏感,注入含油量20mg/L的水50PV使岩心渗透率下降20%。在岩心注水实验中渗透率下降最严重的是双河南岩心,其次是双河北岩心.江河岩心较轻,注入精细过滤水的双河北岩心渗透率下降大大减少.说明悬浮固体是造成注水堵塞的主要因素。为了解除双河油田注水井的堵塞,研制了含黏土稳定剂、缓蚀剂、铁离子稳定剂、互溶剂的土酸液,与南阳油田使用的低伤害酸液一起,用于1口注水井的解堵,效果良好。图7表4参5。  相似文献   
6.
渣油中硫化物类型分布与化学转化性能   总被引:12,自引:0,他引:12  
用X射线光电子能谱(XPS)定量研究了Athabasca渣油及其加氢裂化渣油,流化焦化渣油中的硫化物类型,用超临界流体萃取分馏将3种渣油分别分离成9-14个窄馏分及残渣,测定其中的硫醚,噻吩,亚砜和砜类硫原子的分布,讨论了加氢裂化和热裂化反应脱除硫化物的反应性能。  相似文献   
7.
基于ISP技术的自动测试系统信号处理研究   总被引:5,自引:2,他引:3  
在VXI总线模块及GPIB仪器构成的自动测试系统中 ,利用ispLSI10 3 2实现了测试信号的动态分配和预处理 ,有效解决了测试平台对多种复杂被测对象的适配问题。  相似文献   
8.
《C语言程序设计》课堂教学方法的探讨   总被引:1,自引:0,他引:1  
王宏林 《数字社区&智能家居》2007,2(6):1440-1440,1455
《C语言程序设计》一直是计算机专业及相关专业的专业基础课。该课程既难教又难学。传统的教学方法往往过分注重语法形式的介绍,却忽视了算法的讲解,使得学生无法解决一些实际编程,也很容易挫伤学生的学习兴趣。为此应以算法教学为主。因材施教,合理使用教材,在改用多媒体教学的同时,适当配以板书。调动学生的主观能动性,提高其编程能力。  相似文献   
9.
Wang  Yantao  Wang  Quan  Suo  Daxiang  Wang  Tiezheng 《Neural computing & applications》2021,33(14):8107-8117

Traffic sign recognition and lane detection play an important role in traffic flow planning, avoiding traffic accidents, and alleviating traffic chaos. At present, the traffic intelligent recognition rate still needs to be improved. In view of this, based on the neural network algorithm, this study constructs an intelligent transportation system based on neural network algorithm, and combines machine vision technology to carry out intelligent monitoring and intelligent diagnosis of traffic system. In addition, this study discusses in detail the core of the monitoring system: multi-target tracking algorithm, and introduces the complete implementation process and details of the system, and highlights the implementation and tracking effect of the multi-target tracker. Finally, this study uses case identification to analyze the effectiveness of the algorithm proposed by this paper. The research results show that the proposed method has certain practical effects and can be used as a reference for subsequent system construction.

  相似文献   
10.
The decision making trial and evaluation laboratory (DEMATEL) method is a useful tool for analyzing correlations among factors using crisp values. However, the crisp values are inadequate to model real-life situations due to the fuzziness and uncertainty that are frequently involved in judgments of experts. The aim of this paper is to extend the DEMATEL method to an uncertain linguistic environment. In this paper, the correlation information among factors provided by experts is in the form of uncertain linguistic terms. A formula is first presented to transform correlation information from uncertain linguistic terms to trapezoidal fuzzy numbers. Then, we aggregate the transformed correlation information of each expert into group information using the operations of trapezoidal fuzzy numbers. The importance and classification of factors are determined via fuzzy matrix operations. Furthermore, a causal diagram is constructed to vividly show the different roles of factors. Finally, an example is used to illustrate the procedure of the proposed method.  相似文献   
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