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1.
胡衍芝  顾德英 《中国激光》1990,17(12):721-725
本文报道了CSP Al_xGa_(1-x)As单模激光器的性能及其制造技术.  相似文献   
2.
Three kinds of specimens were produced from hot strips of similar composition and same thickness (nominal gauge 4.0 mm) but produced using different technologies, and the dislocation density of these strips was quantitatively measured by positron annihilation technique test. The dislocation morphology and evolution in microstructure of each pass for producing the 1.9 mm hot strip using CSP (compact strip production) technology were observed under an H-800 transmission electron microscope; its density was also quantitatively measured using the positron annihilation technique test, and the factors influencing the dislocation density during the production process were analyzed. The experimental results show that the dislocation density in the microstructure produced using CSP technology is higher than that in the microstructure produced using conventional technology. This result was discussed and confirmed on the basis of the finite element simulation and the theory relevant to dislocations.  相似文献   
3.
CSP生产低碳钢的组织演变和析出物研究   总被引:10,自引:0,他引:10  
为了阐明EAF-LF-CSP工艺生产的低碳钢组织细化机理,在薄板坯和不同道次变形后的同一轧件上取样,利用金相、SEM、TEM、XEDS等技术研究了连轧过程中显微组织演变和钢中第二相析出物.结果表明:与普通连铸板坯相比薄板坯的凝固组织更加细小;随轧制道次增加,薄板坯表面和心部的组织差异逐渐减小,轧后室温组织细化;CSP生产的低碳钢中存在大量纳米尺寸的氧化物和硫化物,起到细化晶粒的作用.CSP生产中采用快速冷却和凝固工艺、单道次大压下连轧工艺和层流冷却工艺,是成品组织细化的主要原因.  相似文献   
4.
Based on experimental data of positron annihilation technology, electrolytic dissolution technique, electron back-scattered pattern, etc. and by analysis the strengthening factors, the strengthening mechanism of ultra-thin hot strip of low carbon steel produced by CSP (Compact Strip Production) technique was investigated. The value of each strengthening mechanism and its contribution percentage to yield strength were achieved. The results show that refinement strengthening is the predominant strengthening mode; precipitation strengthening and dislocation strengthening are second to it, their contributions to yield strength are almost equal.  相似文献   
5.
CSP板坯(Q235B)高温力学性能试验研究   总被引:3,自引:1,他引:2  
采用Gleeble1500对CSP连铸坯(Q235B)进行了热模拟研究;分析了试验温度为800、900、1100℃的横、纵向试样的组织和断口形貌及晶界的元素偏析和夹杂物.结果表明:CSP生产的Q235B连铸坯在600~1 320℃间存在2个脆性温度区,即1 320~1 200℃的第Ⅰ脆性温度区域和600~1 000℃的第Ⅲ脆性温度区域;在1 000~1 200℃温度范围内,Q235B钢具有良好的塑性.而在800℃时试样的Z值为8.46%.Q235B钢的第Ⅲ类脆性区的脆化原因:一方面是形变诱导铁素体呈网状析出,产生应力集中;另一方面是奥氏体低温区域发生的氮化物(AlN)析出产生的晶界脆化.AlN在奥氏体晶界的析出,在拉伸力的作用下易形成应力集中源,使空洞形成、长大并聚集,是铸坯裂纹源.  相似文献   
6.
To simulate more realistically the effects of strains and stresses on the reliability of portable electronic products, lead-free test assemblies were thermally cycled (−45°C/+125°C, 15-min. dwell time, 750 cycles) or isothermally annealed (125°C, 500 h) before the standard drop test. The average number of drops to failure increased when the thermal cycling was performed before the drop test (1,500 G deceleration, 0.5 ms half-sine pulse). However, the difference was not statistically significant due to the large dispersion in the number of drops to failure of the assemblies drop tested after the thermal cycling. On the other hand, the average number of drops to failure decreased significantly when the isothermal annealing was carried out before the drop test. The failure analysis revealed four different failure modes: (1) cracking of the reaction layers on either side of the interconnections, (2) cracking of the bulk solder, (3) mixed mode of component-side intermetallic and bulk solder cracking, and (4) voidassisted cracking of the component-side Cu3Sn layer. The assemblies that were not thermally cycled or annealed exhibited only type (1) failure mode. The interconnections that were thermally cycled before the drop test failed by mode (2) or mode (3). The drop test reliability of the thermally cycled interconnections was found to depend on the extent of recrystallization generated during the thermal cycling. This also explains the observed wide dispersion in the number of drops to failure. On the other hand, the test boards that were isothermally annealed before the drop testing failed by mode (4).  相似文献   
7.
This paper defines a new denotational semantics for the language of Communicating Sequential Processes (CSP). The semantics lies between the existing traces and failures models of CSP, providing a treatment of non-determinism in terms of singleton failures. Although the semantics does not represent a congruence upon the full language, it is adequate for sequential tests of non-deterministic processes. This semantics corresponds exactly to a commonly used notion of data refinement in Z and Object-Z: an abstract data type is refined when the corresponding process is refined in terms of singleton failures. The semantics is used to explore the relationship between data refinement and process refinement, and to derive a rule for data refinement that is both sound and complete. Received October 2001 Revised September 2002, February 2003, June 2004 and October 2005 Accepted November 2005 by I. J. Hayes  相似文献   
8.
CSP线生产C-Mn系热轧双相钢的工业试验   总被引:9,自引:4,他引:5  
介绍了在CSP生产线上利用普通C-Mn钢生产热轧双相钢的工业试验情况,试验研究了该钢的化学成分、试验工艺、成品力学性能和微观组织。试验得出,该钢的力学性能已达到汽车大梁用钢BG510L的水平;与此同时,提出了生产过程中控制铁素体析出量和促进马氏体形成的具体措施。  相似文献   
9.
We show that wide-ranging classes of predicates on the failures-divergences model for CSP can be represented by refinement checks in a general form. These are predicates of a process P expressible as F(P)⊏G(P), where F and G are CSP contexts and ⊏ is refinement. We use ideas similar to full abstraction, but achieve a stronger property than that. Our main result is that topologically-closed predicates are precisely those representable when F and G are both uniformly continuous. We show that sub-classes of predicates such as refinement-closed and distributive ones are represented by special forms of this check.Received November 2003Revised July 2004Accepted December 2004 by M. Leuschel and D. J. Cooke  相似文献   
10.
In this paper a file transmission protocol specification is developed using the combination of two formal methods: CSP and B. The aim is to demonstrate that it is possible to integrate two well established formal methods whilst maintaining their individual advantages. We discuss how to compositionally verify the specification and ensure that it preserves some abstract properties. We also discuss how the structure of the specification follows a particular style which may be generally applicable when modelling other protocols using this combination .  相似文献   
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