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101.
信息分类编码系统是CIMS各有关环节集成的纽带。本文针对NGC-CIMS对信息分类编码系统的需求,提出了一种面向CIMS各环节、分级、分段和柔性的信息分类编码系统的结构模型,在开发初期提出了基于OO的编码模型;在系统实现时,采用了码位依赖关系和基于元数据及码位模式分解的解决方法;在译码系统实现时,提出了基于总控元关系的译码方法;在基于编码的检索上,提出了不完全码的思想。目前该系统已成功得到了厂方应用。 相似文献
102.
在对可视化程序设计实现机制研究的基础上,结合面向对象程序设计提出了一种可扩展对象程序设计方法。以窗体对象研究为出发点,叙述了采用复杂对象模块以及存储管理器实现子复杂对象生成的方法,对大型系统的开发具有一定的现实指导意义。 相似文献
103.
104.
PI Ramzy DN Herndon SE Wolf O Irtun JP Barret RJ Ramirez JP Heggers 《Canadian Metallurgical Quarterly》1998,133(12):1275-1280
BACKGROUND: The relationship of the burn wound flora to microbial pathogens in the tracheobronchial tree has important implications for antimicrobial therapy in the severely burned patient. Management of septic complications is bolstered by surveillance quantitative wound cultures (QWC) and bronchial lavage fluid (BLF) cultures. OBJECTIVES: To compare the organisms present in BLF with those found in QWC and to determine if QWC can predict BLF results. DESIGN: Results of BLF cultures from all patients who underwent bronchial lavage from January 1, 1996, to December 31, 1996, at our institution were compared with QWC data from the same date. Criteria for a positive match included an identical antibiotic susceptibility pattern and biotype. Match rates were calculated qualitatively and quantitatively. RESULTS: In 30 (48%) of the 62 BLF cultures, there was a match between the organism identified in the BLF and the QWC. When strict quantitative criteria were applied, the match rate was only 9 (14%) of 62. Burn size and inhalation injury had no significant effect on match rate. CONCLUSIONS: Whereas the microbial pathogens were similar in the QWC and BLF, linear regression showed no value of QWC in predicting BLF culture results. The difference between qualitative and quantitative match rates suggests cross-colonization between the burn wound and tracheobronchial tree, but little to no cross-infection. The QWC and BLF cultures must be performed independently in determining antimicrobial specificity in the burned patient. 相似文献
105.
Plasma-chemical etching of silicon and silicon compounds is reviewed. It is shown that present data indicates that fluorine atoms and molecules are the main particles responsible for etching of silicon and that atomic fluorine is the main active particle for etching of silicon dioxide. Insufficient data exists to establish the contribution of charged and excited states to the etching of silicon and its compounds but oxygen atoms and molecules are seen to have a strong influence and fluorocarbon radicals can passivate the surface by forming polymer films. 相似文献
106.
It is shown in this paper that under appropriate circumstances it is possible to overcome the difficulties associated with the solution of the equations expressing the antireflection for an inhomogeneous dielectric thin layer. The relations obtained for the indices and the phase can be used to design films with a low reflectance in the neighbourhood of a selected wavelength. Some examples are given. 相似文献
107.
Marcello Sammarra Jean-François Cordeau Gilbert Laporte M. Flavia Monaco 《Journal of Scheduling》2007,10(4-5):327-336
This paper proposes a tabu search heuristic for the Quay Crane Scheduling Problem (QCSP), the problem of scheduling a fixed number of quay cranes in order to load and unload containers into and from a ship.
The optimality criterion considered is the minimum completion time. Precedence and non-simultaneity constraints between tasks
are taken into account. The former originate from the different kind of operations that each crane has to perform; the latter
are needed in order to avoid interferences between the cranes. The QCSP is decomposed into a routing problem and a scheduling
problem. The routing problem is solved by a tabu search heuristic, while a local search technique is used to generate the
solution of the scheduling problem. This is done by minimizing the longest path length in a disjunctive graph. The effectiveness
of our algorithm is assessed by comparing it to a branch-and-cut algorithm and to a Greedy Randomized Adaptive Search Procedure
(GRASP). 相似文献
108.
本文采用一种简单而有效的电化学方法在硫酸铵体系中利用氧化铝模板(AAO)成功制备出规则有序的Ni的管状纳米阵列.使用这种方法可获得外径约为70nm,内径约为50nm的Ni纳米管.对所得的Ni纳米管进行了扫描电镜(SEM)、透射电镜(TEM)、选区电子衍射图(SAED)和X射线衍射(XRD)分析,结果表明:该方法制备的Ni纳米管高度有序,大小均一,其形貌受控于氧化铝模板的结构,外径与模板的孔径相等. 相似文献
109.
110.
在电力电子技术课程教学中,有许多电路需要画波形图进行分析,而这些波形图往往非常复杂,只靠板书既费时费力,图形不够规范,又看不到动态情况,教学效果非常不理想.Matlab/Simulink动态仿真工具为解决此类问题提供了一个很好的的途径.本文介绍了MATLAB/Simulink仿真软件的特点和功能,并以三相桥式全控整流电路为例对其进行了建模和仿真分析.结果表明,利用该软件辅助电力电子教学,不仅建模简单、直观,更改参数方便,交互性较强,能动态显示仿真波形,节约课堂时间,而且可提高学生学习的兴趣,增强学生对相关理论知识的理解. 相似文献