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排序方式: 共有1470条查询结果,搜索用时 125 毫秒
1.
Fiber-optic reflex sensor for in-line production measurement   总被引:1,自引:0,他引:1  
The paper describes experiments concerning distance measurement with fiber-optic sensor and improvement of the measurement principle. The sensor probe was well-designed with a small structure and multi-function. The novel optical fiber probe arrangement as well as the possibilities of use for complex measurement problems are explained using the measurement of an internal screw thread as an example. The experimental results show that the measurement uncertainty of the thread minor diameter can reach ±10 μm, and the stability of the measurement system is better than 0.07%.  相似文献   
2.
揭示了城市技术创新系统和城乡统筹发展的内涵,并在技术创新、增长极和区域经济等理论框架下阐述了城市技术创新与城乡统筹发展的关系,进而提出城市技术创新促进城乡统筹的路径。  相似文献   
3.
InthepastsixyearsChinawasoccupyingthefirstpositionintheamountoffashionmanufactureandexport.Atthesametime,theamountoftextile&fashionproductionaccountsfor 15 %ofGDPandexportamountaccountsfor1/ 4ofGEP .However,Chi nadoesnotplayaleadingroleinglobalfashionindust…  相似文献   
4.
本文运用五种竞争作用力理论,具体分析了中国电子工业的微观环境,通过分析可以看出中国电子工业的外部微观环境主要就是电信运营企业和自身合资企业中中外双方的股东企业。这种结果对分析中国电子工业企业的发展简化了环境。  相似文献   
5.
介绍20世纪90年代以来中国服装业经营模式的发展变化,分析我国服装业虚拟经营的现状和利弊,并对如何有效地发展这种模式提出一些看法和建议。  相似文献   
6.
本文从探究式学习的定义和特征出发,反对不分教学对象差异的"唯探究主义",在大学《现代教育技术》课程的教学中倡导面向全体学生,开展多样化的探究式学习。这就要求在教学过程中,辩证地处理学生自主与教师指导的关系,强调教师与学生的相互倾听,珍视探究中学生的个人观念、独特感受和体验,并引导学生积极反思。  相似文献   
7.
I survey highlights of the practice of physics and allied sciences in Melbourne,Australia, from the 1850s, soon after Europeans first settled in the area, to the present. I note recognizable sites of past and current physical-science activity that may be visited, as well as exhibits of historic items of physics apparatus. I trace the role of physics, in the course of a century and a half, in the evolution of a pioneering settlement into a large city embedded in a modern industrial economy.  相似文献   
8.
The previously synthesised (1–37), (38–75), (76–93), (94–104), (105–117) and (118–129) fragments of the analogue were combined making extensive use of the DCCI/HONSu method. The final coupling involved the (1–75) and (76–129) sub-fragments. Aggregation of the latter fragment caused problems in purification by routine gel filtration methods employing Enzacryl K2 or Sephadex LH60. The fully protected (1–129) product was partially purified by washing, then deprotectcd and purified by gel filtration and ion exchange chromatography. Satisfactory removal of the acetamidomethyl group used for cysteine protection could not be achieved.  相似文献   
9.
Based on the development prospect of cosmetics industry, the advantage of light industry characteristic and the foundation of applied chemistry in Jiangnan University, a systematic upgrading of applied chemistry was carried out through "emerging engineering education (3E)" project "upgrade and practice of chemistry-related majors of local and/or trade university responding to the social developments" supported by the Ministry of Education. On the basis of investigation and analysis, the orientation and training goal of applied chemistry were updated first, and then the curriculum system was determined and the curriculum construction is strengthened, so as to achieve more distinctive characteristics, more solid foundation and more comprehensive quality. In view of the new requirements of the 3E for talent training, some practices have been formed in the aspects of multi-disciplinary integration, multi-angle coordination and close integration to industry. Contributing the development of cosmetics industry and seizing the commanding point of science and technology from the perspective of talent training, will play a unique role in human social progress.  相似文献   
10.
Kullberg N  Vilén M  Sund P  Talaslahti M  Sara R 《Talanta》1999,49(5):234-968
A number of sequential injection analysis (SIA) measurement methods have been developed during the last years. Almost all have been used in laboratory conditions with good results, but very few have been implemented as on-line methods, applied to non-stop measurements, producing immediate results for process control. The transfer of an SIA system from laboratory to an industrial facility [J. Ruzicka, Anal. Chim. Acta 261 (1992) 3] requires a whole new range of details to be taken into account. Some SIA platform related topics will be discussed. There are numerous ways of building an SIA system that meets the needs of the industry. One alternative, SIAmate, is presented.  相似文献   
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