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The mathematical model of wetting angle of heterogeneous nucleation

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Science China(Technological Sciences) 2004年第4期47卷 391-397页

作者： HUANG Cheng1, SONG Bo1, MAO Jinghong2 & ZHAO Pei3.1. School of Metallurgical and Ecological engineering, university of Science and Technology Beijing, Beijing 100083. China 2. School of Material Science, university of Science and Technology Beijing, Beijing 100083. China 3. Central Iron and Steel {3. institute, Beijing 100081, China 1. School of Metallurgical and Ecological engineering University of Science and Technology Beijing 100083 Beijing China 2. School of Material Science University of Science and Technology Beijing 100083 Beijing China 3. Central Iron and Steel research institute 100081 Beijing China

The heterogeneous nucleation has been analyzed in terms of the thermodynamic theory, and the mathematical model of wetting angle of heterogeneous nucleation has been developed based on the dynamic requirements of hetero- and homogeneous nucleation. With the wetting angel model, the wetting angles of different catalysts in liquid iron have been calculated. The result shows that the wetting angle of most catalysts is smaller than 40, and the value of f() is far less than 1. The wetting angles of TiN, TiC and RE2O3.are smaller, while the wetting angle of MnO is bigger among the ordinary nucleation catalysts. The wetting angles calculated by this model are in agreement with the results of other research work.

关键词： heterogeneous nucleation, mathematical model, wetting angle, undercooling.

景德镇艺术职业大学山谷学生公寓,景德镇,江西,中国

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世界建筑 2024年第4期 82-85页

作者： Architectural Design & research institute of Tsinghua university Co., Ltd. 清华大学建筑设计研究院有限公司

景德镇艺术职业大学山谷学生公寓项目核心理念是用最低介入的方式最大程度地保留场地内的自然山水要素,创造低成本的、促进学生社交的立体聚落艺术社区。项目位于校园美丽的茶园和茂密的松林之间,跨越在山谷湿地和小溪之上。从尊重场地... 详细信息

景德镇艺术职业大学山谷学生公寓项目核心理念是用最低介入的方式最大程度地保留场地内的自然山水要素,创造低成本的、促进学生社交的立体聚落艺术社区。项目位于校园美丽的茶园和茂密的松林之间,跨越在山谷湿地和小溪之上。从尊重场地精神的角度出发,景德镇的市井烟火气息、千年茶园的独特风貌,都对设计产生了影响。建筑底层架空,尊重场地自然要素特征。悬挑、斜柱、架空、跨越等低环境影响度的设计方式,解决地形高差、减少土方工程,并最大化保留低洼处的湿地作为整个区域的泄洪通道。

关键词：学生公寓土方工程底层架空尊重要素特征景德镇

Development and Application of High Performance X80 Line Pipe for the 2^(nd) West-East Gas Pipeline

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Journal of Iron and Steel research International 2011年第S1期18卷 39-48页

作者： LI He-lin 1 , HUO Chun-yong 1 , JI Ling-kang 1, 2 , LI Yang 1, 3.(1. CNPC Tubular Goods research institute, Xi’an 710065, China 2. . School of Material Science and engineering, Xi’an Jiaotong {3., Xi’an 710049, China 3. School of Material Science and engineering, {3. of Science and Technology Beijing, Beijing 100083. China) CNPC Tubular Goods Res Inst Xian 710065 Peoples R China Xi An Jiao Tong Univ Sch Mat Sci & Engn Xian 710049 Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

It is the development tendency of gas pipeline to improve strength of line pipe and transmission pressure, which is an important symbol of the progress of gas pipeline technology. The 2nd West-East Gas Pipeline (the 2 nd WEGP) is the largest-scale X80 high pressure gas pipeline project in the world. Through the joint development project by Pipeline Company, research institute, and steel company, a series of achievements of technology have been obtained, which makes it possible to apply pressure of 12 MPa and X80 LSAW and HSAW pipe for the 2 nd WEGP. Specifications of X80 steel and pipe have been issued based on API 5L. High performance X80 steel and pipe have been developed and meets the Specification. General design conception of applying HSAW pipe and LSAW pipe on gas transmission trunk line with large diameter and high pressure has been established. Failure control of the 2 nd WEGP has been carried out to avoid failure and reduce the lost which based on analysis of pipeline failure mode. In this paper, research and development of high performance X80 welded pipe, establishment of technical route of joint application of HSAW and LSAW steel pipe and key technology of failure control are emphatically discussed.

关键词： 2 nd WEGP acicular ferrite failure control arrest toughness strain-based design

Adsorption of surfactants onto acrylic ester resins with different pore size distribution

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Science China Chemistry 2006年第5期49卷 445-453页

作者： YANG Weiben1,2,3.LI Aimin1,3.CAI Jianguo1,3.MENG Guanhua1,3.& ZHANG Quanxing1,3.1. State Key Laboratory of Pollution Control and Resource Reuse,School of the Environment,Nanjing university,Nanjing 210093.China 2. Nanjing College of Chemical Technology,Nanjing 210048,China 3. Jiangsu engineering & Technology research Center for Organic Toxicant Control and Resource Reuse,Nanjing 21003.,China 1. State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China 2. Nanjing College of Chemical Technology Nanjing 210048 China 3. Jiangsu engineering & Technology research Center for Organic Toxicant Control and Resource Reuse Nanjing 210038 China

In this study, a series of acrylic ester resins with different pore size distribution were prepared successfully by varying the type and the amount of pore-forming agents. In order to inves-tigate the adsorption behavior and mechanism of surfactants on acrylic ester resins, three kinds of surfactants were utilized as adsorbates that were sodium 6-dodecyl benzenesulfonate (6-NaDBS), sodium 1-dodecyl benzene sulfonate (1-NaDBS) and sodium 1-dodecyl sulfonate, respectively. It was observed that the surface area was available in a particular pore size and an appropriate pore size of resins appeared to be more important for the adsorption of surfactants. As compared to commercial acrylic ester resins XAD-7 and HP2MG, 50# and 3.# resins exhibited more excellent adsorption properties toward 1-NaDBS and 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir, and double-Langmuir models. Two models provided very good fittings for all resins over the temperature range studied. The investigation indicated that electrostatic attraction and hydrogen bond between resins and surfactants were the main forces and had an obvious effect on adsorption proc-ess.

关键词： acrylic ester resin, surfactant, adsorption, pore size distribution, isotherm.

Multi-channel neural mass modelling and analyzing

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Science China(Information Sciences) 2011年第6期54卷 1283-1292页

作者： CUI Dong 1 , LI XiaoLi 2 , JI XueQing 3.& LIU LanXiang 3.1 institute of Information Science and engineering, Yanshan university, Qinhuangdao 066004, China 2 institute of Electrical engineering, Yanshan university, Qinhuangdao 066004, China 3.The No.1 Hospital of Qinhuangdao, Qinhuangdao 066000, China 1. institute of Information Science and engineering Yanshan University Qinhuangdao 066004 China2. Institute of Electrical Engineering Yanshan University Qinhuangdao 066004 China3. The No.1 Hospital of Qinhuangdao Qinhuangdao 066000 China

Multi-channel neural signals generated by a computational model can help understand the mechanism of EEG rhythms, analyze brain functional connectivity and evaluate neural signal processing methods. In this study, a two-kinetics lumped-parameter neural mass model is extended to a multi-kinetics and multi-channel coupled model. This new model can effectively simulate the coupled dynamics activities between different areas in the brain. The simulation results show that the proposed model can generate neural signals with various frequency bands, from delta wave (1-4 Hz) to gamma wave (3.-70 Hz), and the dynamics of the simulated neural signals is more complicated. The simulation analysis can also reveal the relationship between the coupled neural networks and the rhythm of neural populations, and the simulated neural signals can present the bi-modal and uni-modal phenomenon in the frequency domain when the coupling strength of models increases. Finally, analysis of an epileptic EEG signal from a rat demonstrates that the coupling among the neural populations can induce a large-scale seizure.

关键词： multi-channel neural mass model coupling spectrum synchronization epilepsy

Approximation of dense-n/2-subgraph and table compression problems

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Science China Mathematics 2005年第9期48卷 1223-1233页

作者： XU Dachuan~1 HAN Jiye~2 & DU Dongle~3.1. College of Applied Sciences,Beijing university of Technology,Beijing 100022,China 2. institute of Applied Mathematics,Academy of Mathematics and systems Science,Chinese Academy of Sciences,Beijing 100080,China 3. Faculty of Administration,university of New Brunswick,P.O.Box 4400,Fredericton,NB E3. 5A3.Canada College of Applied Sciences Beijing University of Technology Beijing 100022 China institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China Faculty of Administration University of New Brunswick P.O. Box 4400 Fredericton NB E3B 5A3 Canada

We develop improved approximation algorithms for two NP-hard problems: the dense-n/2-subgraph and table *** on SDP relaxation and advanced rounding techniques,we first propose 0. 5982 and 0. 5970-approximation algorithms respec- tively for the dense-n/2-subgraph problem (DSP) and the table compression problem (TCP). Then we improve these bounds to 0. 6243.and 0. 6708 respectively for DSP and TCP by adding triangle inequalities to strengthen the SDP *** results for TCP beat the 0. 5 bound of a simple greedy algorithm on this problem,and hence answer an open question of Anderson in an affirmative way.

关键词： dense-n/2-subgraph problem(DSP) table compression problem(TCP) SDP approximation ratio

Detection of water in petroleum inclusions and its implications

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Science Bulletin 2006年第12期51卷 1501-1507页

作者： CAO Jian1, YAO Suping1, HU Wenxuan1, ZHANG Yijie2, WANG Xulong3. ZHANG Yueqian3.& TANG Yong3.1. State Key Laboratory for Mineral Deposit research, Department of Earth Sciences, Nanjing university, Nanjing 210093. China 2. research {3. of Exploration and Development, PetroChina, Bei- jing 100083. China 3. research {3. of Exploration and Development, Xinjiang Oilfield Company, PetroChina, Karamay 83.000, China State Key Laboratory for Mineral Deposit research Department of Earth Sciences Nanjing University Nanjing 210093 China research institute of Exploration and Development PetroChina Beijing 100083 China research institute of Exploration and Development Xinjiang Oilfield Company PetroChina Karamay 834000 China

FTIR spectra of inclusions sampled from fault-zone reservoirs of the northwestern Junggar Basin show that water, with different abundances, does exist in petroleum inclusions. It is thus implied that petroleum inclusions can seldom form without water. Different inclusions hosted in one single grain, and formed in one oil charging phase, have a largely varied ratio of water to oil and slightly changed CH3.CH2 ratio. This likely provides evidence for fault-related episodic migration and accumulation of hydrocarbons.

关键词： water in petroleum inclusions forming mechanism of inclusions episodic migration and accumulation of hydrocarbons FTIR microspectroscopy Junggar Basin.

Theory of truth degrees of propositions in the logic system Ln^＊

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Science in China(Series F) 2006年第4期49卷 471-483页

作者： LI Jun1,2 & WANG Guojun1,3.1. institute of Mathematics, Shaanxi Normal university, Xi’an 710062, China 2. School of Sciences, Lanzhou university of Technology, Lanzhou 73.050, China 3. {3. Center for Science, Xi’an Jiaotong university, Xi’an 710049, China 1. institute of Mathematics Shaanxi Normal University Xi’an 710062 China 2. School of Sciences Lanzhou University of Technology Lanzhou 730050 China 3. research Center for Science Xi’an Jiaotong University Xi’an 710049 China

By means of infinite product of uniformly distributed probability spaces of cardinal n the concept of truth degrees of propositions in the n-valued generalized Lu- kasiewicz propositional logic system Ln^＊ is introduced in the present paper. It is proved that the set consisting of truth degrees of all formulas is dense in [0,1], and a general expres- sion of truth degrees of formulas as well as a deduction rule of truth degrees is then obtained. Moreover, similarity degrees among formulas are proposed and a pseudo-metric is defined therefrom on the set of formulas, and hence a possible framework suitable for developing approximate reasoning theory in n-valued generalized Lukasiewicz propositional logic is established.

关键词： truth degree similarity degree approximate reasoning.

Parameter identification theory of a complex model based on global optimization method

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Science China(Physics,Mechanics & Astronomy) 2008年第11期51卷 1722-1732页

作者： QU Jie1, JIN QuanLin2 & XU BingYe3.1 College of Automotive engineering, South China university of Technology, Guangzhou 510640, China 2 Beijing research {3. of Mechanical and Electrical Technology, Beijing 100083. China 3.Department of engineering Mechanics, Tsinghua university, Beijing 100084, China 1. College of Automotive engineering South China University of Technology Guangzhou 510640 China 2. Beijing research institute of Mechanical and Electrical Technology Beijing 100083 China 3. Department of engineering Mechanics Tsinghua University Beijing 100084 China

With the development of computer technology and numerical simulation technology, computer aided engineering (CAE) technology has been widely applied to many fields. One of the main obstacles, which hinder the further application of CAE technology, is how to successfully identify the parameters of the selected model. An elementary framework for parameter identification of a complex model is provided in this paper. The framework includes the construction of objective function, the design of the optimization method and the evaluation of the identified results, etc. The parameter identification process is described in this framework, taking the parameter identification of the superplastic constitutive model considering grain growth for Ti-6Al-4V at 927°C as an example. The objective function is the weighted quadratic sums of the difference between the experimental and computational data for the stress-strain relationship and the grain growth relationship; the designed optimization method is a hybrid global optimization method, which is based on the feature of the objective function and incorporates the strengths of genetic algorithm (GA), the Levenberg-Marquardt algorithm and the augmented Gauss-Newton algorithm. The reliability evaluation of parameter identification result is made through the comparison between the calculated and experimental results and between the theoretical values of the parameters and the identified ones.

关键词： constitutive model parameter identification theory inverse analysis global optimization