To decrease the metal losses of RF spiral inductor,a novel layout structure with gradually reduced metal line width and space from outside to inside is presented. This gradual changed inductor has less eddy-current ef...To decrease the metal losses of RF spiral inductor,a novel layout structure with gradually reduced metal line width and space from outside to inside is presented. This gradual changed inductor has less eddy-current effect than the conventional inductor of fixed metal width and space. So the series resistance can be reduced and the quality （Q） factor of the inductor relating to metal losses is increased. The obtained experimental results corroborate the validity of the proposed method. For a 6nH inductor on high-resistivity silicon at 2.46GHz,Q factor of 14.25 is 11.3% higher than the conventional inductor with the same layout size. This inductor can be integrated with radio frequency integrated circuits to gain better performance in RF front end of a wireless communication system.展开更多
储罐清洗是石油化工企业,尤其是油库和炼厂等企业的一项经常性的工作,主要有人工清罐和机械清罐两种方法,人工清罐方法由于存在巨大的安全隐患、能源浪费、环境污染等问题,正逐步被淘汰。目前采用的机械清罐方法大都是基于击碎溶解原理...储罐清洗是石油化工企业,尤其是油库和炼厂等企业的一项经常性的工作,主要有人工清罐和机械清罐两种方法,人工清罐方法由于存在巨大的安全隐患、能源浪费、环境污染等问题,正逐步被淘汰。目前采用的机械清罐方法大都是基于击碎溶解原理的COW方法,该法依靠在罐顶多点式均布的清洗机的射流来击碎、溶解、回收罐内积存的沉积物,从而达到消除罐底沉积物的目的,与人工清罐法相比,采用C O W机械清罐法具有一定的优点,但仍存在着清洗前临时管线安装工作量大、人员上下罐调节清洗机频繁、需要向罐内持续注入惰性气体等弊端,当采用该方法,对大型储罐,尤其是容积在5万m3以上的储罐进行清洗时,清洗工期一般都需两个月以上。本文提出了一种基于大流量扰动技术的新型储罐机械清洗方法,旨在解决大型原油储罐的安全、高效清洗难题,与现有清洗方法相比,具有无需注氮、安全性高、施工效率高、人工劳动强度低等显著优点。展开更多
We have theoretically studied the nucleation of superconductivity in doubly connected superconductors in the form of long superconducting cylinders. The giant vortex states are investigated with the nonlinear Ginzburg...We have theoretically studied the nucleation of superconductivity in doubly connected superconductors in the form of long superconducting cylinders. The giant vortex states are investigated with the nonlinear Ginzburg-Landau theory. The solutions of Ginzburg-Landau equations are solved numerically with relaxation method. The quantum size effect is clearly shown through the calculation of free energy.展开更多
文摘To decrease the metal losses of RF spiral inductor,a novel layout structure with gradually reduced metal line width and space from outside to inside is presented. This gradual changed inductor has less eddy-current effect than the conventional inductor of fixed metal width and space. So the series resistance can be reduced and the quality （Q） factor of the inductor relating to metal losses is increased. The obtained experimental results corroborate the validity of the proposed method. For a 6nH inductor on high-resistivity silicon at 2.46GHz,Q factor of 14.25 is 11.3% higher than the conventional inductor with the same layout size. This inductor can be integrated with radio frequency integrated circuits to gain better performance in RF front end of a wireless communication system.
文摘储罐清洗是石油化工企业,尤其是油库和炼厂等企业的一项经常性的工作,主要有人工清罐和机械清罐两种方法,人工清罐方法由于存在巨大的安全隐患、能源浪费、环境污染等问题,正逐步被淘汰。目前采用的机械清罐方法大都是基于击碎溶解原理的COW方法,该法依靠在罐顶多点式均布的清洗机的射流来击碎、溶解、回收罐内积存的沉积物,从而达到消除罐底沉积物的目的,与人工清罐法相比,采用C O W机械清罐法具有一定的优点,但仍存在着清洗前临时管线安装工作量大、人员上下罐调节清洗机频繁、需要向罐内持续注入惰性气体等弊端,当采用该方法,对大型储罐,尤其是容积在5万m3以上的储罐进行清洗时,清洗工期一般都需两个月以上。本文提出了一种基于大流量扰动技术的新型储罐机械清洗方法,旨在解决大型原油储罐的安全、高效清洗难题,与现有清洗方法相比,具有无需注氮、安全性高、施工效率高、人工劳动强度低等显著优点。
基金The project supported by Natural Science Foundation from Beijing Normal University.Acknowledgments H. Zhao wishes to thank Profs. Fang-Lin Peng, Jue- Lian Shen, and Jia-Cai Nie for helpful discussions
文摘We have theoretically studied the nucleation of superconductivity in doubly connected superconductors in the form of long superconducting cylinders. The giant vortex states are investigated with the nonlinear Ginzburg-Landau theory. The solutions of Ginzburg-Landau equations are solved numerically with relaxation method. The quantum size effect is clearly shown through the calculation of free energy.
