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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.
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   
4.
薄板坯连铸连轧半无头轧制工艺   总被引:12,自引:1,他引:11  
毛新平 《钢铁》2003,38(7):23-27
针对薄板坯连铸连轧工艺,从工艺、设备、布置等各方面探讨了实现连续化生产的相关技术问题,在薄板坯连铸连轧工艺中采用半无头轧制工艺,一方面避免了常规热连轧机组无头轧制工艺的投资和焊接质量的问题,另一方面避免了单坯轧制工艺存在的问题,是高效经济地生产薄且宽热轧薄板的一种很有发展前途的工艺。  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.
从热轧润滑机理和现场技术改进等方面,分析了辊缝润滑在CSP生产线上的应用情况。结果表明,在热轧精轧机使用辊缝润滑技术,优化了轧制工艺条件,提高了轧辊的性能及轧制公里数,降低了辊耗,改善了成品带钢的表面质量。  相似文献   
7.
A mathematical model has been built to numerically predict the thermal history of thin slab during CSP (compact strip process) rolling. To estimate the temperature distribution in the slab mare accurately, the mathematical model combines heat transfer in the slab, in the roll, and at the roll-slab interface during bite. The numerical results agree with on-site running data, which proves the reliabili~, of the mathematical model. The results show that roll chilling has a significant effect on the temperature distribution in the slab.  相似文献   
8.
曹峥 《电力建设》2005,26(2):65-0
从Windows2000的安全体系结构介绍着手,描述了CSP(加密服务提供者)在整个体系结构中的地位和作用,并分析了CSP自身的安全性,提出了通过开发客户端专用CSP增强Windows操作系统安全性的思想,最后从软件和硬件2种途径,提出开发客户端专用CSP的方法。  相似文献   
9.
A Conceptual Model of Service Customization and Its Implementation   总被引:2,自引:0,他引:2       下载免费PDF全文
With the development of Internet and next generation networks in telecommunications, more and more new services are required to be introduced into networks. Introducing new services into traditional network is always associated with standardizing new protocols. The progress of protocol standardization usually takes several years, which cannot meet the increasing demands of the applications in Internet and next generation networks. Service customization in network systems may be one possible solution to cope with this problem. Based on the principle that network service is provided by interactions among protocol entities, this paper proposes a conceptual model of service customization (SECUM) by separating the service logic from protocol interactive logic within existing network architecture. The theory of Communicating Sequential Processes (CSP) is used to formalize the SECUM in order to locate exactly the service logic and to define precisely the SECUM. For validating the SECUM‘s usability in practical network systems, this paper also proposes an implementation model for SECUM: a component-based protocol implementation model (CPIM). CPIM discomposes protocol entity into application component, service component, message component and communication component. Service component associates application component with message component. Users or network managers can customize network services by configuring service component. The paper shows respectively the applications of SECUM and CPIM by proposing a customizable IP service model based on SECUM and describing an implementation of Session Initiation Protocol (SIP) based on CPIM. Compared with the existing service-customization techniques, SECUM is a service customization model internal to network system and may provide more powerful capabilities of service customization.  相似文献   
10.
当操作CSP器件不小心掉片时,应力会使CSP焊点破裂或至少引起开裂,这将导致以后的失效。采用底部填充工艺将CSP粘接到基板,有助于分散这一应力,不像倒装片,底部填充的目的是改善热性能,CSP的目的是提高抗冲击和抗震动能力,目前底部填充工艺有多种方法,但怎样才能使成本最低,周期最短,操作最方便呢,本文从底部填充点涂技术, 流出量涌塞,双路点涂、温度控制等方面详细介绍了CSP底部填充工艺。  相似文献   
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