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An assessment of China-Japan-Korea Free Trade Agreement’s economic and environmental impacts on China

Zhaoyang LIU, Xianqiang MAO, Wei TANG, Tao HU, Peng SONG

《环境科学与工程前沿（英文）》 2012年第6卷第6期页码 849-859 doi: 10.1007/s11783-012-0432-9

摘要： Recently, China, Japan, and the Republic of Korea (Korea) are conducting a government-commissioned feasibility study on the Free Trade Agreement among the three countries (CJKFTA) to form a regional free trade zone in East Asia. Considering that freer trade can cause unexpected impact on domestic environment, there is a need to evaluate the environmental impact of such a trade policy. This move should be made to help negotiators understand and pay more attention to environmental issues during CJKFTA negotiations, and to help lobby with the government to carry out appropriate policy instruments for adaptation or mitigation. Following the Chain Reaction Assessment Method that integrates and links the elements of trade, production, and environment, the present research aims to quantitatively assess CJKFTA’s possible impact on China’s environment. This is done by estimating the variations of China’s major conventional pollutants and greenhouse gases (GHGs) emission in two policy scenarios to represent CJKFTA’s scale and composition effects on China’s environment. Estimating the variations is based on a static Computable General Equilibrium model, working with Global Trade Analysis Project (GTAP) 7 database and China’s energy-environment statistics. Based on these assessments, CJKFTA is predicted to lead to notable environmental impact, including increased emissions of agricultural total nitrogen, agricultural total phosphorus, chemical oxygen demand, and GHGs. On the other hand, decreased emissions of industrial SO and dust are also expected to happen. Suitable policies need to be made to combat negative effects and amplify positive ones, while aiming at a more sustainable regional freer trade system.

关键词： Free Trade Agreement Strategic Environmental Assessment Chain Reaction Assessment Method Computable General Equilibrium model Global Trade Analysis Project

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2016—2035年中国经济总量及其结构分析预测

李平,娄峰,王宏伟

《中国工程科学》 2017年第19卷第1期页码 13-20 doi: 10.15302/J-SSCAE-2017.01.003

摘要：

本文综合考虑了未来影响中国潜在经济增长的若干主要因素及其传导机制，构建了经济系统模型，预测了未来20年中国的经济规模及其结构变化。在基准情景下，2016—2020、2021—2025、2026—2030和2031—2035年四个时期我国国内生产总值（GDP）增长率分别为6.4 %、5.6 %、4.9 %和4.5 %。2035年中国不变价GDP规模将为2000年的10.06倍、2010年的3.99倍、2020年的2.02倍。未来20年内，以投资拉动为主的经济增长模式将逐步转变为以消费需求为主导的发展新模式。面对发达经济体可能低速增长的国际环境以及国内新增劳动力逐渐减少的情况，中国经济需要加强研发和教育投入，提高投入效率和全要素生产率，推进技术进步和制造业的转型与升级；加快推动财税金融体制改革和收入分配体制改革，推进城镇化和第三产业发展。

关键词：经济预测经济增长结构分析可计算一般均衡

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Non-equilibrium model for catalytic distillation process

WANG Feng, ZHAO Ning, LI Junping, XIAO Fukui, WEI Wei, SUN Yuhan

《化学科学与工程前沿（英文）》 2008年第2卷第4期页码 379-384 doi: 10.1007/s11705-008-0071-7

摘要： A new improved tri-diagonal method was developed for the non-equilibrium stage model of the catalytic distillation by coupling consumptive reaction coefficient. The reactions in the distillation column were divided into generative reaction and consumptive reaction. The non-equilibrium stage model was introduced for the catalytic distillation process of the dimethyl carbonate (DMC) synthesis by urea methanolysis over solid based catalyst, and the improved tri-diagonal method was used to solve the model equations. Comparison of predicted results with experiment data shows that the mean relative error of the yield of DMC was 3.78% under different conditions such as different operating pressures and reaction temperatures. The improved tri-diagonal matrix method could avoid the negative values of the liquid compositions during the calculations and restrain the fluctuation of compositions by slowing down the variations of the values in the iteration. The modeling results show that the improved tri-diagonal method was appropriate for system containing a wide range of boiling point components and a different rate of reactions.

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Statics of levitated vehicle model with hybrid magnets

Desheng LI, Zhiyuan LU, Tianwu DONG

《机械工程前沿（英文）》 2009年第4卷第1期页码 35-39 doi: 10.1007/s11465-009-0002-4

摘要： By studying the special characteristics of permanent and electronic magnets, a levitated vehicle model with hybrid magnets is established. The mathematical model of the vehicle is built based on its dynamics equation by studying its machine structure and working principle. Based on the model, the basic characteristics and the effect between the excluding forces from permanent magnets in three different spatial directions are analyzed, statics characteristics of the interference forces in three different spatial directions are studied, and self-adjusting equilibrium characteristics and stabilization are analyzed. Based on the structure above, the vehicle can levitate steadily by control system adjustment.

关键词： magnetic levitation permanent magnet modeling equilibrium

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Thermodynamic analysis of reaction pathways and equilibrium yields for catalytic pyrolysis of naphtha

《化学科学与工程前沿（英文）》 2022年第16卷第12期页码 1700-1712 doi: 10.1007/s11705-022-2207-6

摘要： The chain length and hydrocarbon type significantly affect the production of light olefins during the catalytic pyrolysis of naphtha. Herein, for a better catalyst design and operation parameters optimization, the reaction pathways and equilibrium yields for the catalytic pyrolysis of C_5–8 n/iso/cyclo-paraffins were analyzed thermodynamically. The results revealed that the thermodynamically favorable reaction pathways for n/iso-paraffins and cyclo-paraffins were the protolytic and hydrogen transfer cracking pathways, respectively. However, the formation of light paraffin severely limits the maximum selectivity toward light olefins. The dehydrogenation cracking pathway of n/iso-paraffins and the protolytic cracking pathway of cyclo-paraffins demonstrated significantly improved selectivity for light olefins. The results are thus useful as a direction for future catalyst improvements, facilitating superior reaction pathways to enhance light olefins. In addition, the equilibrium yield of light olefins increased with increasing the chain length, and the introduction of cyclo-paraffin inhibits the formation of light olefins. High temperatures and low pressures favor the formation of ethylene, and moderate temperatures and low pressures favor the formation of propylene. n-Hexane and cyclohexane mixtures gave maximum ethylene and propylene yield of approximately 49.90% and 55.77%, respectively. This work provides theoretical guidance for the development of superior catalysts and the selection of proper operation parameters for the catalytic pyrolysis of C_5–8 n/iso/cyclo-paraffins from a thermodynamic point of view.

关键词： naphtha catalytic pyrolysis reaction pathway equilibrium yield

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矿物浮选吸附平衡模型构建与应用：精准解析矿物表面离子 / 药剂特征吸附

高雅,付心壮,韩海生,王丽,岳彤,孙伟

《中国工程科学》 2023年第25卷第6期页码 248-258 doi: 10.15302/J-SSCAE-2023.07.020

摘要：

矿物浮选吸附平衡模型是准确描述矿物浮选过程中所涉及的矿物表面离子 / 药剂吸附平衡的数学模型，首次实现了矿物表面位点与浮选药剂吸附作用亲和性的量化解析。传统浮选理论对矿物表面作用位点缺乏科学描述，难以阐明浮选药剂的吸附作用能力及平衡状态，新浮选药剂体系开发多以“试错法”“复配法”等经验性方法为主。药剂选择性吸附作为浮选作业的核心机制，若不能准确预测其在各矿物表面的吸附行为，将严重限制浮选工艺智能化控制的发展。本文详细论述了矿物浮选吸附平衡模型的构建原理，以赤铁矿 ‒ 石英和一水硬铝石 ‒ 高岭石两个浮选体系为例，通过对少量实验数据的拟合计算，解析出矿物表面活性位点密度Ns、加 / 去质子反应常数Kt1/Kt2、药剂吸附常数Kf等矿物浮选特征常数。将解析的矿物浮选特征常数代入到平衡模型中，预测出各条件下矿物表面电性、离子及浮选药剂的吸附量，通过零电点、实验及测试等方法验证了可靠性，形成了矿物浮选过程预测系统的内核算法。该算法对各条件下每种矿物药剂吸附的初步准确预测，可在一定程度上反映其可浮性趋势，有助于缩短浮选工艺开发周期，对矿物表面药剂吸附机理研究、浮选药剂分子设计、浮选工艺流程优化及智能控制等具有重要意义。

关键词：矿物加工；浮选机理；矿物浮选吸附平衡模型；可浮性预测；矿物浮选特征常数

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General expression for linear and nonlinear time series models

Ren HUANG, Feiyun XU, Ruwen CHEN

《机械工程前沿（英文）》 2009年第4卷第1期页码 15-24 doi: 10.1007/s11465-009-0015-z

摘要： The typical time series models such as ARMA, AR, and MA are founded on the normality and stationarity of a system and expressed by a linear difference equation; therefore, they are strictly limited to the linear system. However, some nonlinear factors are within the practical system; thus, it is difficult to fit the model for real systems with the above models. This paper proposes a general expression for linear and nonlinear auto-regressive time series models (GNAR). With the gradient optimization method and modified AIC information criteria integrated with the prediction error, the parameter estimation and order determination are achieved. The model simulation and experiments show that the GNAR model can accurately approximate to the dynamic characteristics of the most nonlinear models applied in academics and engineering. The modeling and prediction accuracy of the GNAR model is superior to the classical time series models. The proposed GNAR model is flexible and effective.

关键词： linear and nonlinear autoregressive model system identification time series analysis

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基于正定约束广义秩信号模型的低复杂度稳健自适应算法 Article

Yu-tang ZHU,Yong-bo ZHAO,Jun LIU,Peng-lang SHUI

《信息与电子工程前沿（英文）》 2016年第17卷第11期页码 1245-1252 doi: 10.1631/FITEE.1601112

摘要：本文针对广义秩信号模型提出一种低复杂度的稳健自适应波束形成算法，用来抑制期望信号的阵列响应失配和接收信号的协方差矩阵失配。该波束形成算法不仅考虑期望信号以及接收信号协方差矩阵不确定集的范数有界性，还保证期望信号协方差矩阵的正定性。最终，本文在最差性能优化准则下推出一个计算简单的闭式加权矢量。计算机仿真结果验证了所提波束形成算法的有效性和稳健性。

关键词：波束形成；广义秩；低复杂度；正定约束；模型失配

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Measurement and correlation of the solid-liquid equilibrium of 2-(

Yanhong SUN, Zhiyong LI, Chuang XIE, Wei CHEN, Cui ZHANG

《化学科学与工程前沿（英文）》 2013年第7卷第1期页码 110-115 doi: 10.1007/s11705-013-1316-7

摘要： In this work, the enthalpy of fusion and melting points of 2-( -butyl)-5-methylphenol (2B5MP) and 2-( -butyl)-4-methylphenol (2B4MP) were measured by differential scanning calorimetry (DSC). The binary solid-liquid equilibrium (SLE) of both compounds were predicted by integrated computer aided system (ICAS) and measured by DSC. The corresponding eutectic molar composition is 0.6998 and the eutectic temperature is 281.96 K. The quasi-static heat capacities of 2B5MP and 2B4MP were evaluated by stochastic temperature modulation DSC technique (TOPEM). The SLE experimental data were correlated using the Margules, Wilson, and non-random two liquid (NRTL) equations and a good agreement between measurement and calculation could be obtained.

关键词： solid-liquid equilibrium (SLE) eutectic integrated computer aided system (ICAS) TOPEM correlation

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A novel intravenous general anesthetic--- emulsified isoflurane: from bench to bedside

null

《医学前沿（英文）》 2012年第6卷第4期页码 381-387 doi: 10.1007/s11684-012-0229-z

摘要：

Application of volatile anesthetics greatly alters modern medicine. There are obvious advantages of volatile anesthetics such as strong anesthetic potency, rapid onset and elimination through respiration system. Isoflurane is one of the most widely used volatile anesthetics in clinic. Emulsified isoflurane, the emulsion of isoflurane, is a novel intravenous general anesthetic. With the development of emulsified isoflurane in the past fifteen years, its utility has spread from intravenous general anesthesia to various fields including regional anesthesia, organ protection, as well as anesthetic pharmacological study. In this review, we will summarize literatures of emulsified isoflurane about its history, clinical application and future potential utility in the above mentioned fields.

关键词： emulsified isoflurane (EI) general anesthesia regional anesthesia organ protection anesthetic pharmacological study

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Brown marine algae turbinaria conoides as biosorbent for Malachite green removal: Equilibrium and kinetic

R. RAJESH KANNAN, M. RAJASIMMAN, N. RAJAMOHAN, B. SIVAPRAKASH,

《环境科学与工程前沿（英文）》 2010年第4卷第1期页码 116-122 doi: 10.1007/s11783-010-0006-7

摘要： In this study, the biosorption of Malachite green (MG) onto Turbinaria conoides, brown marine algae, was studied with respect to initial pH, temperature, initial dye concentration, and sorbent dosage. The optimum initial pH and temperature values for MG removal were found to be 8.0 and 30°C, respectively. Sorbent dosage was found to strongly influence the removal of MG. Equilibrium studies were carried out to test the validity of the Langmuir ( = 66.6 mg/g and = 0.526 mL mol/L) and the Freundlich ( = 1.826 and = 3.751 mg/g) isotherms. The kinetic studies indicated the validity of the pseudo first-order and second-order equation.

关键词： Malachite green (MG) Turbinaria conoides marine algae equilibrium studies biosorption

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Microenvironmental time-activity patterns in Chongqing, China

Yu ZHAO, Shuxiao WANG, Gangcai CHEN, Fei WANG, Kristin AUNAN, Jiming HAO

《环境科学与工程前沿（英文）》 2009年第3卷第2期页码 200-209 doi: 10.1007/s11783-009-0010-y

摘要： An investigation using recall questionnaires was conducted in winter and autumn 2006 to evaluate the time-activity patterns in Chongqing, China. The average time spent in seven microenvironments (MEs) including outdoors, transit, living room, bedroom, kitchen, classroom/office, and other indoors were found to be about 3.5, 1.1, 2.5, 9.7, 1.4, 4.2, and 1.7 h per day, respectively. According to the results of a nonparametric test, the sampling period and day of week were significant for the variation of the time spent in all MEs except for transit and outdoors. The time budget was analyzed using a general linear model (GLM), which exhibited significant variability by demographic factors such as gender, age, residence, education, and household income.

关键词： time-activity patterns microenvironment general linear model (GLM) Chongqing China

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Numerical investigation of circle defining curve for two-dimensional problem with general boundaries

Chung Nguyen VAN

《结构与土木工程前沿（英文）》 2019年第13卷第1期页码 92-102 doi: 10.1007/s11709-018-0472-8

摘要： The scaled boundary finite element method (SBFEM) is applied to the static analysis of two dimensional elasticity problem, boundary value problems domain with the domain completely described by a circular defining curve. The scaled boundary finite element equations is formulated within a general framework integrating the influence of the distributed body force, general boundary conditions, and bounded and unbounded domain. This paper investigates the possibility of using exact geometry to form the exact description of the circular defining curve and the standard finite element shape function to approximate the defining curve. Three linear elasticity problems are presented to verify the proposed method with the analytical solution. Numerical examples show the accuracy and efficiency of the proposed method, and the performance is found to be better than using standard linear element for the approximation defining curve on the scaled boundary method.

关键词： exact geometry circular defining curve general boundaries SBFEM

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coated on endotracheal tube with or without epidural lidocaine reduces isoflurane requirement during general

null

《医学前沿（英文）》 2012年第6卷第3期页码 302-306 doi: 10.1007/s11684-012-0194-6

摘要：

This study was designed to evaluate the effect of tracheal topical anesthesia using EMLA^? Cream (EC) coated on the endotracheal tube (ETT) with or without epidural anesthesia (EA) on isoflurane requirement during general anesthesia (GA) and investigate whether EC coated on the ETT with EA was associated with the additive effect compared with the effect when each anesthetic was administered independently. The prospective randomized, double-blinded, and controlled study included 60 ASA I–II patients scheduled for upper abdominal surgery requiring GA. Patients were randomly assigned to one of the following groups: group 1 received GA, group 2 received EC+ GA, group 3 received GA+ EA, and group 4 received EC+ GA+ EA. Isoflurane was administered at the required concentrations to maintain the mean arterial pressure at a level not exceeding 20% of preoperative values. The percentage mean expired concentration (%MEC) was used in calculating the isoflurane requirement. Emergence agitation, postoperative sore throat, and hoarseness were recorded. Groups 2, 3, and 4 exhibited a significant reduction on isoflurane requirement compared with group 1 (P<0.05). The isoflurane requirement evaluated by %MEC decreased by 12%, 38%, and 50% in groups 2, 3, and 4, respectively. The incidence of emergence agitation was significantly lower in groups 2 and 4 than those in groups 1 and 3 (P<0.05). Tracheal topical anesthesia using EC coated on ETT with or without EA reduced the isoflurane requirement during GA, indicating that EC combined with EA exhibited an additive effect on the requirement of general anesthetic.

关键词： EMLA? Cream epidural anesthesia general anesthesia isoflurane lidocaine

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The next step of community health construction: Training general practitioners and implementing health

Kan ZHANG MM, Wei DONG MM, Ying-Yao CHEN MD,

《医学前沿（英文）》 2010年第4卷第2期页码 134-138 doi: 10.1007/s11684-010-0041-6

摘要： This article discusses the concept of health management and stresses that community health management should be the starting point of community health service, necessitating a paradigm shift from observing the treatment-oriented medical model to observing the prevention-and-health management-based medical model. Community health construction has entered a new phase, one which highlights the need to train general practitioners in practice-based life cycle health management. In addition, general practitioners should assume the mission of implementing community health management.

关键词： community health general practitioners health management