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NUMERICAL ANALYSIS OF LARGE TURBINE ROTOR SYSTEM UNDER THENONLINEAR OIL-FILM FORCE AND ALFORD FORCE

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NUMERICAL ANALYSIS OF LARGE TURBINE ROTOR SYSTEM UNDER THENO...

The Seco.d International co.ference on Dynamics Vibration and co.trol

作者： Shuqian Cao, Xiaohui Xin and Qian Ding School of Mechanical Engineering, tianjin University, tianjin 300072, China Offshore Oil Engineering co. ltd., CNOOC,tianjin 300452,China

＜正＞The steam-excited vibration of rotors for supercritical and ultra supercritical steam turbines is one of the main problems in the industry of turbomachinery. The problem of instability as a result of the effect of both nonlinear airflow exciting-vibration force （Alford force） and nonlinear oil-film force have not been studied thoroughly up to now. The stability of a rigid unbalanced Jeffco.t rotor supported by two short journal bearings was

关键词： turbine rotor nonlinear oil-film force Alford force bifurcation chaos

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能量三定律的基础研究

天津科技 2018年第2期45卷 28-30页

作者：陈春祥天津宏能科技有限公司天津301700

基于力学基本原理和应用基本原理,提出能量转换的物理属性定律,重力能量定律和轴﹑轮﹑质点三力结构能量效应定律3条能量定律,证实了这些定律的客观存在。描述了其基础原理与定律普适特性,重大物理突破点、展望,它有望使人类进入对能量... 详细信息

基于力学基本原理和应用基本原理,提出能量转换的物理属性定律,重力能量定律和轴﹑轮﹑质点三力结构能量效应定律3条能量定律,证实了这些定律的客观存在。描述了其基础原理与定律普适特性,重大物理突破点、展望,它有望使人类进入对能量和动力利用的时代成为现实。

关键词：能量三定律重力能量定律能量转换物理属性定律轴、轮、质点三力结构能量效应定律

Polycistronic strategy for cyanobacterial expression vector co.struction: co.transcription of a human gene and a selective marker gene

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Progress in Natural science:Materials International 2005年第9期15卷 798-803页

作者： ZHANG Yukun1, SHI Dingji2, ZHAO Feifei1, YU Meimin1 and RU Binggen1(1. co.lege of Life science, Peking University, Beijing 100871, China 2. co.lege of Marine sciences & Engineering, tianjin University of science & technology, tianjin 300450, China) co.lege of Life science Peking University Beijing 100871 China. co.lege of Marine sciences & Engineering Tianjin University of Science & Technology Tianjin 300450 China

A polycistronic expression vector, pKGA-NTF1, was co.structed for the cyanobacterium. Within this vector, the spectinomycin/streptomycin resistance gene (aadA) facilitated the selection of transformants when co.transcribed with favorite genes. A natural glnA gene was selected as the platform to introduce the plasmid into a neutral site of the Synechoco.cus sp. PCC 7002 chromosome. Function of the vector was demonstrated by the insertion of a modified human Trefoil factor 3 gene (NTF1) to upstream of the aadA gene and by the analyses of the transformed strains. Antibiotics resistance assays showed that the dicistronic expression cassette co.ferred high spectinomycin resistance to both the E. co.i cells and the Synechoco.cus cells. PCR analysis and Western-blot analysis were carried out to co.firm the integration and expression of the NTF1 gene, respectively. Through simple molecular manipulations, the artificial polycistronic structure described here can be co.veniently used to express other favorable genes or operons in cyanobacteria, and to study the cyanobacterial gene expression as well.

关键词： cyanobacterial transformation human Trefoil factor 3 polycistronic expression Synechoco.cus sp. PCC 7002 vector co.struction.

企业免费实现ORACLE Web方式信息发布的技术方法

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计算机工程与应用 2004年第17期40卷 190-194,221页

作者：张云飞中铁十三局集团电务工程有限公司天津300232

利用GNU免费的ApacheWebServer1.3.27版本软件提供www服务,采用GCC编译标准C程序,运用OCI接口,通过CGI方式,在Oracle8iForSolaris2.7工作站环境下访问后台数据库,以B/S(浏览器/服务器)方式,动态发布企业生产和管理信息,量化实现企业管... 详细信息

利用GNU免费的ApacheWebServer1.3.27版本软件提供www服务,采用GCC编译标准C程序,运用OCI接口,通过CGI方式,在Oracle8iForSolaris2.7工作站环境下访问后台数据库,以B/S(浏览器/服务器)方式,动态发布企业生产和管理信息,量化实现企业管理业务规则。

关键词： UNIX Free Web Apache CGI OCI oracle

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中升挑战肉鸡行业高峰论坛

中升挑战肉鸡行业高峰论坛

Seasonal variation analysis of atmospheric CH_4,N_2O and co.2 in tianjin offshore area

第五届（2018）全球肉鸡产业研讨会暨第六届中国白羽肉鸡产业发展大会

作者： tianjin SPEERISE CHALLENGE BIOtechnology co.,ltd. 天津市中升挑战生物科技有限公司

中国肉鸡行业高峰论坛是由天津市中升挑战生物科技有限公司承办的行业高端技术交流平台。自2010年始,在中国畜牧业协会的支持和论坛组委会的努力下至今已成功举办四届,每届论坛都会邀请到行业主管领导、全国知名行业专家、大型养殖企业...

中国肉鸡行业高峰论坛是由天津市中升挑战生物科技有限公司承办的行业高端技术交流平台。自2010年始,在中国畜牧业协会的支持和论坛组委会的努力下至今已成功举办四届,每届论坛都会邀请到行业主管领导、全国知名行业专家、大型养殖企业高管等高端领军人物为主讲嘉宾,分享他们的研究成果,让广大同行能够及时汲取先进的权威理论指导,共同促进行业的持续高速发展,提升整个行业的科技含量和影响力。并作为交流平台分享行业资讯,研讨禽业发展趋势。经过多年努力,肉鸡行业高峰论坛在业内已形成广泛影响,吸引了大批行业专家以及大型养殖企业参与。

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science China Earth sciences 2010年第8期53卷 1205-1215页

作者： KONG ShaoFei, LU Bing, HAN Bin, BAI ZhiPeng, XU Zhun, YOU Yan, JIN LiangMao, GUO XiaoYang & WANG Rui State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and co.trol, co.lege of Environmental science and Engineering, Nankai University, tianjin 300071, China 1. State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and co.trol College of Environmental Science and Engineering Nankai University Tianjin 300071 China

The co.centrations of CH4, N2O and co. at the sea level were observed from November 2007 to August 2008 in order to study the greenhouse gases in the tianjin offshore area of Bohai Sea. CH4 co.centrations varied from 1.87 to 2.61 ppm with the highest value appearing in summer and the lowest in winter. The co.centration range of N2O was 319.3 to 347.7 ppb, with the maximal value appearing in winter. co. was higher in the heating season than in non-heating season in this area. co.centrations of the three greenhouse gases in the study area exceeded the 2005 global background values. Backward trajectory model was used to analyze the sources. All three gases were influenced evidently by co.tinental sources in the inshore area during the sampling periods. Every gas was co.pared with each other by co.relation analysis, showing that the co.relation of co. and N2O was more significant than to CH4 and their relationship with meteorological factors was co.sistent. It can be co.cluded these three greenhouse gases may be influenced by some similar sources, especially for co. and N2O.

关键词： Bohai Sea greenhouse gas offshore observation backward trajectory model sources

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浅谈多层建筑排水工程设计施工要点

施工技术 2009年第S1期38卷 609-612页

作者：李秀珠天津城市道路管网配套建设投资有限公司天津300384

排水工程是建筑安装工程的重要组成部分,也是影响建筑质量的重要因素。针对多层住宅排水系统安装使用过程中出现的问题,对其产生的原因做出分析,并提出改进措施,提高建筑排水工程的施工质量,保证其使用的安全性和稳定性。

关键词：多层建筑排水工程管材防漏

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我国咸味香精风味化发展方向和研发新思路

食品科技 2010年第5期35卷 281-283页

作者：马长明天津春发食品配料有限公司天津300300

咸味食品香精是食品行业领域一个新兴的产业,经过20多年的发展,2009年产销量达到70多亿元。咸味香精是以美拉德反应产物为主要成分的反应基料复配而成,属于天然、安全的食品添加剂,适应我国食品行业快速发展的大工业化生产中确保食品风... 详细信息

咸味食品香精是食品行业领域一个新兴的产业,经过20多年的发展,2009年产销量达到70多亿元。咸味香精是以美拉德反应产物为主要成分的反应基料复配而成,属于天然、安全的食品添加剂,适应我国食品行业快速发展的大工业化生产中确保食品风味的一致性和质量稳定的需求。据预测,未来10~20年咸味香精行业还将会保持15%~20%的年增长速度。咸味香精行业的发展将不可避免的面临越来越激烈的市场竞争,在香味香精生产企业品牌化、高科技化的竞争格局下,咸味香精产品研发个性化、风味化必将成为企业市场竞争的制高点。

关键词：咸味香精市场竞争风味化

Artificial Neural Network for co.bining Forecasts

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Journal of Systems Engineering and Electronics 1995年第2期6卷 58-64页

作者： Shanming Shi, Li D. Xu & Bao Liu(Department of co.puter science, University of co.orado at Boulder, Boulder, co.80309, USA)(Department of MSIS, Wright State University, Dayton, OH 45435,USA)(Institute of Systems Engineering, tianjin University, tianjin 30 Department of co.puter science University of Colorado at Boulder CO 80309 USA Department of MSIS Wright State University Dayton OH 45435 USA Institute of Systems Engineering Tianjin University Tianjin 300072 China

This paper proposes artificial neural networks (ANN) as a tool for nonlinear co.bination of forecasts. In this study, three forecasting models are used for individual forecasts, and then two linear co.bining methods are used to co.pare with the ANN co.bining method. The co.parative experiment using real--world data shows that the prediction by the ANN method outperforms those by linear co.bining methods. The paper suggests that the ANN co.bining method can be used as- an alternative to co.ventional linear co.bining methods to achieve greater forecasting accuracy.

关键词： Artificial neural network,Forecasting co.bined forecasts Nonlinear systems.