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密闭输血器与开放输液器联置在手术室的应用
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作者 刘莹 陈晓梅 张雪梅 《内蒙古医学杂志》 1998年第6期383-383,共1页
密闭输血(或输液)方法简单、方便,有效的防止交叉感染及避免技术操作上的原因造成的液体污染,在临床上广泛应用。但密闭输血、输液在手术室内有其不便之处,在手术室单位时间中所用的药液种类较多,更换频繁,尤其在危重病人抢救时... 密闭输血(或输液)方法简单、方便,有效的防止交叉感染及避免技术操作上的原因造成的液体污染,在临床上广泛应用。但密闭输血、输液在手术室内有其不便之处,在手术室单位时间中所用的药液种类较多,更换频繁,尤其在危重病人抢救时,显示出密闭输液法的不灵活之处。开... 展开更多
关键词 输液器 密闭式 开放式 联置 手术室
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REVERSIBLE LOGIC GATE NETWORK CASCADE BASED ON PERMUTATION GROUP 被引量:1
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作者 管致锦 秦小麟 戴华 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第3期219-223,共5页
The cascade of reversible logic gate network with n inputs and n outputs forms a group isomorphic to the symmetric group S2^n. Characteristics of a number of gates from the set of all generalized Toffoli gates are stu... The cascade of reversible logic gate network with n inputs and n outputs forms a group isomorphic to the symmetric group S2^n. Characteristics of a number of gates from the set of all generalized Toffoli gates are studied. Any permutation Sn is proved to be generated by a n-cycle 9 and a permutation τ= (ij,ik) together. It shows that any neighboring 2-cycle permutation can be generated by at most two NOT gates without ancilla bit. Based on the above theory, a cascade algorithm for reversible logic gate networks is proposed. A reversible example of logic gate network cascade is given to show the correctness of the algorithm. 展开更多
关键词 logic gates cascade connection permutation group
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A 10Gb/s GaAs PHEMT High Gain Preamplifier for Optical Receivers
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作者 焦世龙 杨先明 +5 位作者 赵亮 李辉 陈镇龙 陈堂胜 邵凯 叶玉堂 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1902-1911,共10页
A high gain cascade connected preamplifier for optical receivers is developed with 0.5μm GaAs PHEMT technology from the Nanjing Electronic Devices Institute. To begin with, the transimpedance amplifier has a -3dB ban... A high gain cascade connected preamplifier for optical receivers is developed with 0.5μm GaAs PHEMT technology from the Nanjing Electronic Devices Institute. To begin with, the transimpedance amplifier has a -3dB bandwidth of 10GHz, with a small signal gain of around 9dB. The post-stage distributed amplifier (DA) has a -3dB bandwidth of close to 20GHz,with a small signal gain of around 12dB. As a whole,the cascade preamplifier has a measured small signal gain of 21.3dB and a transimpedance of 55.3dBΩ in a 50Ω system. With a higher signal-to-noise ratio than that of the TIA and a markedly improved waveform distortion compared with that of the DA, the measured output eye diagram for 10Gb/s NRZ pseudorandom binary sequence is clear and symmetric. 展开更多
关键词 GaAs PHEMT optical receiver PREAMPLIFIER eye diagram CASCADE
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Federated UKF algorithm for mobile location estimation with TDOA/Doppler measurements 被引量:1
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作者 蔡苗红 金乐 +1 位作者 何峰 吴乐南 《Journal of Southeast University(English Edition)》 EI CAS 2009年第3期294-298,共5页
In order to enhance the location estimation performance of mobile station(MS)tracking and positioning, a new method of mobile location optimal estimation based on the federated filtering structure and the simplified... In order to enhance the location estimation performance of mobile station(MS)tracking and positioning, a new method of mobile location optimal estimation based on the federated filtering structure and the simplified unscented Kalman filter (UKF) is presented. The proposed algorithm uses the Singer mobile statement model as the reference system, and the simplified UKF as the subfilters. The subfilters receive the two groups of independently detected time difference of arrival (TDOA) measurement inputs and Doppler measurement inputs, and produce local estimation outputs to the main estimator. Then the main estimator performs the optimal fusion of the local estimation outputs according to the scalar weighted rule, and a global optimal or suboptimal estimation result is achieved. Finally the main estimator gives feedback and reset information to the subfilters and the reference system for next step estimation. In the simulations, the estimation performance of the proposed algorithm is evaluated and compared with the simplified UKF method with TDOA or Doppler measurement alone. The simulation results demonstrate that the proposed algorithm can effectively reduce the location estimation error and variance of the MS, and has favorable performance in both root mean square error(RMSE) and mean error cumulative distribution function(CDF). 展开更多
关键词 data fusion mobile location estimation federated filtering unscented Kalman filter(UKF)
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pH Stability of Defibrase_ in Aqueous Solution Determined by En-zyme-linked Immunosorbent Assay
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作者 赵会英 郑俊民 +2 位作者 徐晖 魏刚 赵怀清 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第3期144-147,共4页
Stability of Defibrase in various pH buffer solutions was investigated. Enzyme-linked immuno-sorbent assay (ELISA) and coagulating time method were used to assess antigenic stability and coagulating stability, respect... Stability of Defibrase in various pH buffer solutions was investigated. Enzyme-linked immuno-sorbent assay (ELISA) and coagulating time method were used to assess antigenic stability and coagulating stability, respectively. The change of antigenic activities and coagulating activities of Defibrase in the same buffer solutions (pH 6, 7 and 8, with the exception of pH 3.6) showed similar tendency to decline with the time. Concentrated Defi-brase was relatively stable at neutral pH 6~7, more than 95% of its initial activities (100BUmL-1) was kept after a 10-day storage at 40 oC, whereas in pH 3.6 and pH 9 buffer solutions, diluted Defibrase was very labile. Addition of Triton X-100 or bovine serum albumin could effectively prevent loss of Defibrase by minimizing adsorption of De-fibrase to plastic surface (P<0.005). Concentration of Defibrase could also affect its stability in aqueous solutions. 展开更多
关键词 STABILITY DEFIBRASE ELISA
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TCP-Rab: a receiver advertisement based TCP protocol 被引量:4
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作者 汤旭红 刘正蓝 朱淼良 《Journal of Zhejiang University Science》 EI CSCD 2004年第11期1352-1360,共9页
With the evolution of network technologies, the deficiencies of TCP protocol are becoming more and more distinct. The new TCP implementation, called Receiver Advertisement Based TCP (TCP-Rab) proposed here to eliminat... With the evolution of network technologies, the deficiencies of TCP protocol are becoming more and more distinct. The new TCP implementation, called Receiver Advertisement Based TCP (TCP-Rab) proposed here to eliminate these deficiencies, adopts two basic mechanisms: (1) Bandwidth Estimation and (2) Immediate Recovery. Bandwidth estimation is carried out at the receiver, and the result is sent back to the sender via the acknowledgments. Immediate Recovery guarantees high performance even in lossy link. Rab can distinguish the reason for packet loss, and thus adopt appropriate recovery strategy. For loss by network congestion, it will back off its congestion window, and for loss by link errors, it will recover the congestion window immediately. Simulations indicated that Rab has superiority over other TCP implementations. 展开更多
关键词 Bandwidth Estimation Immediate Recovery TCP protocol
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Comparison of Biotribology of Swine Compact Bone Against UHMWPE 被引量:3
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作者 WANG Qing-liang GE Shi-rong 《Journal of China University of Mining and Technology》 EI 2007年第1期133-137,共5页
A pin-on-disk tribometer was used, in a comparative test to observe the tribological behavior of the swine femoral bone against UHMWPE with dry friction, physiological water and human plasma lubrication. The wear mech... A pin-on-disk tribometer was used, in a comparative test to observe the tribological behavior of the swine femoral bone against UHMWPE with dry friction, physiological water and human plasma lubrication. The wear mechanisms of swine bones and UHMWPE were investigated by SEM. The experimental results of these wear tests demon- strated that both the friction coefficient and wear rate of UHMWPE were the lowest when human plasma lubrication was used. The wear mechanism of the compact bone was mainly fatigue wear with dry friction, corrosive wear under physiological water lubrication and abrasive wear with human plasma lubrication. For UHMWPE, the wear mecha- nism was adhesive wear and plastic deformation with dry friction, serious ploughing and fatigue fracture wear under physiological water lubrication, fine ploughing and plastic deformation with human plasma lubrication. An analysis of nitrogen elements on the wear surface of UHMWPE indicated that the content of nitrogen in worn areas was 16 times higher than that in unworn areas, which proved that serum protein deposition occurred on worn areas. 展开更多
关键词 swine bone UHMWPE friction and wear wear mechanism
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An Approach to Reasoning Topological Relations Between Areal Objects Under Randomness
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作者 DENGMin ZHANGXuesong LIUWenbao 《Geo-Spatial Information Science》 2004年第4期255-261,278,共8页
This paper describes the geometric and statistical properties of areal object under randomness. In order to describe formally such a uncertain topological relation, a new formal model (i.e. 4ID model) is proposed. On ... This paper describes the geometric and statistical properties of areal object under randomness. In order to describe formally such a uncertain topological relation, a new formal model (i.e. 4ID model) is proposed. On the basis of this, the effects of positional uncertainty on topological relations between areal objects are investigated in detail. Some possibility functions for the determination of relations are constructed based on the assumption that randomness of point location complies with a normal distribution, and the concept of uncertain sets of topological relations under randomness is introduced. 展开更多
关键词 topological relations RANDOMNESS positional error
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Low power implementation of datapath using regularity
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作者 赖莉雅 刘鹏 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第6期596-600,共5页
Datapath accounts for a considerable part of power consumption in VLSI circuit design. This paper presents a method for physical implementation of datapath to achieve low power consumption. Regularity is a characteris... Datapath accounts for a considerable part of power consumption in VLSI circuit design. This paper presents a method for physical implementation of datapath to achieve low power consumption. Regularity is a characteristic of datapath and the key of the proposed method, where synthesis is tightly combined with placement to make full use of regularity, so that low power consumption is achieved. In This paper, a new concept of Synthesis In Relative Placement (SIRP) is given to deal with the semi-regularity in some datapath. Experimental results of a sample circuit validated the proposed method. 展开更多
关键词 Datapath Low power REGULARITY Relative placement
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Hierarchical On-line Scheduling of Multiproduct Batch Plants with a Combined Approach of Mathematical Programming and Genetic Algorithm 被引量:1
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作者 陈理 王克峰 +1 位作者 徐霄羽 姚平经 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第1期78-84,共7页
In this contribution we present an online scheduling algorithm for a real world multiproduct batch plant. The overall mixed integer nonlinear programming (MINLP) problem is hierarchically structured into a mixed integ... In this contribution we present an online scheduling algorithm for a real world multiproduct batch plant. The overall mixed integer nonlinear programming (MINLP) problem is hierarchically structured into a mixed integer linear programming (MILP) problem first and then a reduced dimensional MINLP problem, which are optimized by mathematical programming (MP) and genetic algorithm (GA) respectively. The basis idea relies on combining MP with GA to exploit their complementary capacity. The key features of the hierarchical model are explained and illustrated with some real world cases from the multiproduct batch plants. 展开更多
关键词 online scheduling multiproduct batch plant mixed integer nonlinear programming mathematical programming genetic algorithm
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Design of multi-module experiment-rig of vessel electrical propulsion prime mover
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作者 XIEChun-ling WANGYuan-hui 《Journal of Marine Science and Application》 2005年第1期26-29,共4页
Combined power plant is widely used in large or medium surface vessel for its predominant performance. It is important to research on using combined power plant as electrical propulsion prime mover for developing the ... Combined power plant is widely used in large or medium surface vessel for its predominant performance. It is important to research on using combined power plant as electrical propulsion prime mover for developing the electric propulsion warship.This paper, designs a multi-module experiment-rig and introduces its composition, working principle and disposition scheme,and carried out the dynamic characteristic experiment of the GTD350 gas turbine. 展开更多
关键词 electrical propulsion modular composition combined power plant
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English Connector as Binding Term for Conjunction and Relative Pronoun
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作者 Japen Sarage 《Sino-US English Teaching》 2015年第9期660-666,共7页
As grammatical words, conjunction and relative pronoun play a similar role. They join clauses, phrases, and even words. The terms independent and dependent clauses have become popular for quite a long time. When the c... As grammatical words, conjunction and relative pronoun play a similar role. They join clauses, phrases, and even words. The terms independent and dependent clauses have become popular for quite a long time. When the concept of clause and sentence meets at the presence of NP (Noun Phrase) and VP (Verb Phrase), there is a right to consider construction as an S or a sentence leaving the conjunction and relative pronoun as means of uniting device and leaving every NP-VP construction as equal units. By employing an embedding theory, we can see hidden parts of a sentence and their roles in other sentences. This article tries to see if it is still necessary to distinguish between dependent and independent clauses. 展开更多
关键词 CONNECTOR CONJUNCTION relative pronoun
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Pinch Location of the Hydrogen Network with Purification Reuse 被引量:7
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作者 刘桂莲 黎浩 +1 位作者 冯霄 邓春 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第12期1332-1340,共9页
In the hydrogen network with the minimum hydrogen utility flow rate,the pinch appears at the point with zero hydrogen surplus,while the hydrogen surpluses of all the other points are positive.In the hydrogen purity pr... In the hydrogen network with the minimum hydrogen utility flow rate,the pinch appears at the point with zero hydrogen surplus,while the hydrogen surpluses of all the other points are positive.In the hydrogen purity profiles,the pinch can only lie at the sink-tie-line intersecting the source purity profile.According to the alternative distribution of the negative and positive regions,the effect of the purification to the hydrogen surplus is analyzed.The results show that when the purification is applied,the pinch point will appear neither above the purification feed nor between the initial pinch point and the purification feed,no matter the purification feed lies above or below the initial pinch point.This is validated by two case studies. 展开更多
关键词 PURIFICATION PINCH hydrogen network hydrogen surplus hydrogen utility flow rate
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Nonlinear cascade control of single-rod pneumatic actuator based on an extended disturbance observer 被引量:1
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作者 LI Ai-min MENG De-yuan +1 位作者 LU Bo LI Qing-yang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第6期1637-1648,共12页
Precise position tracking control of the single-rod pneumatic actuator is considered and a nonlinear cascade controller is developed.The proposed controller comprises an extended disturbance observer(EDOB)and a nonlin... Precise position tracking control of the single-rod pneumatic actuator is considered and a nonlinear cascade controller is developed.The proposed controller comprises an extended disturbance observer(EDOB)and a nonlinear robust control law synthesized by the backstepping method.The EDOB is designed to estimate not only the influence of disturbances but also the parameter uncertainties.With the use of parameter and disturbance estimates,the nonlinear cascade controller,which consists of an outer position tracking loop and an inner load pressure loop,is further designed to attenuate the effects of parameter and disturbance estimation errors.The stability of the closed-loop system is proven by means of Lyapunov theory.Extensive comparative experimental results obtained verify the effectiveness of the proposed nonlinear cascade controller and its performance robustness to parameter and external disturbance variations in practical implementation. 展开更多
关键词 electro-pneumatic servo system extended disturbance observer cascade control robust control position tracking
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Political Advertising and Propaganda Within Spiral of Silence-Agenda Setting Theory
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作者 Hakan ALP 《Journalism and Mass Communication》 2016年第1期12-18,共7页
Political communication is an interactive process by which politicians transmit information and political discourse to voters and receive feedback through media. This communication process is a two way process of comm... Political communication is an interactive process by which politicians transmit information and political discourse to voters and receive feedback through media. This communication process is a two way process of communication between politicians and voters by which, on the one hand, politicians transmit their thoughts and wills to voters, and on the other hand voters communicate their opinions to politicians, after interpreting, in different ways, the messages that they received. The key objective of political communication is to persuade or influence and cause voters, who are the target audience, to vote for a particular party by convincing them. In order to ensure the smooth operation of political communication processes it is essential that the parliament, government, political parties, non-governmental organizations, environmentalist groups and pressure groups also actually take part in this process The decisive and transformative power of mass media and advertising phenomenon on the political systems has grown to become more and more influential in the recent years. The use of information considerably increases in line with the increase in the use of propaganda. No doubL this information age has turned the world into "a universal village". On the one hand, the concentration in media and on the other hand rapid developments in Internet technologies expose societies to the bombardment of messages. Being exposed to or bombarded by numerous varieties of messages in their daily lives lead to the creation of variabilities and instabilities in individual's behaviors. Accordingly, political organizations while trying to convey messages to masses through political communication and advertising have to deliver systematic, comprehensible and influential messages by taking the advantage of visualization as much as possible. 展开更多
关键词 political advertising spiral of silence agenda setting COMMUNICATION
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Media Agenda and Citizen Perceptions About the Economic Crisis in Mexico: The Case of South-Center Area
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作者 Jose Antonio Meyer Rodriguez 《Journalism and Mass Communication》 2011年第1期68-78,共11页
This paper reports the role of national newspapers in the agenda setting process about the economical crisis in Mexico and its impact, as important mediators, in the public opinion, in a context of high social uncerta... This paper reports the role of national newspapers in the agenda setting process about the economical crisis in Mexico and its impact, as important mediators, in the public opinion, in a context of high social uncertainty. It has sought to know whether the responses of federal government economic policy have influenced the presidential level of acceptance and whether the adverse outcomes in federal elections intermediate reveal significant aspects in the electoral behavior of the population for presidential succession 2012. This involved measuring citizens perceptions and decisions before the reforms and their consequences, analyze government communication strategies to the crisis and assess the treatment and approaches news from three newspapers about the events concerning the public agenda. The analysis has focused on three states of the central-south of Mexico. 展开更多
关键词 public agenda public opinion economical policy presidential acceptation south-center area
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Research on Optimizing Numerical Calculation of Posture Equations based on Six DOF Stewart Platform
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作者 Yinmu Wei 《International Journal of Technology Management》 2014年第8期27-29,共3页
The paper study position positive solution method based on 6-TPS parallel mechanism, and establish general kinematics model of 6-TPS parallel mechanism, gives the numerical method of positive solution based on a kind ... The paper study position positive solution method based on 6-TPS parallel mechanism, and establish general kinematics model of 6-TPS parallel mechanism, gives the numerical method of positive solution based on a kind of position, deduced the forward position solution iteration format, and use MATLAB for the 6-TPS parallel mechanism kinematics to simulation, results show that solving program has stability, fast. effective. 展开更多
关键词 Parallel mechanism KINEMATICS forward kinematics numerical simulation
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Unit Commitment with Production Cost Uncertainty: A Recourse Programming Method
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作者 H. Borsenberger Ph. Dessante G. Sandou 《Journal of Energy and Power Engineering》 2011年第2期164-172,共9页
Many studies have considered the solution of Unit Commitment problems for the management of energy networks. In this field, earlier work addressed the problem in determinist cases and in cases dealing with demand unce... Many studies have considered the solution of Unit Commitment problems for the management of energy networks. In this field, earlier work addressed the problem in determinist cases and in cases dealing with demand uncertainties. In this paper, the authors develop a method to deal with uncertainties related to the cost function. Indeed, such uncertainties often occur in energy networks (waste incinerator with a priori unknown waste amounts, cogeneration plant with uncertainty of the sold electricity price...). The corresponding optimization problems are large scale stochastic non-linear mixed integer problems. The developed solution method is a recourse based programming one. The main idea is to consider that amounts of energy to produce can be slightly adapted in real time, whereas the on/off statuses of units have to be decided very early in the management procedure. Results show that the proposed approach remains compatible with existing Unit Commitment programming methods and presents an obvious interest with reasonable computing loads. 展开更多
关键词 Unit Commitment dynamic programming stochastic programming UNCERTAINTY energy management systems RECOURSE Lagrangian relaxation.
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The Environmental Factors and Strategic Priorities in Northwest Power Development
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《Electricity》 2003年第4期3-6,共4页
Based on the energy distribution and economy status In the Northwest Region in China, this paper analyzes the probability of power sources complementation between Northwest Power Grid and the adjacent regional power g... Based on the energy distribution and economy status In the Northwest Region in China, this paper analyzes the probability of power sources complementation between Northwest Power Grid and the adjacent regional power grids, and points out that the strategic emphases for Northwest power development are to speed up 750 kV transmis-sion system construction, expand the Regional power market, rolling-develop hydrdpower stations on the Upper Yellow River, speed up thermal power bases construction and boost the interconnection between Northwest and North China, etc. 展开更多
关键词 energy distribution power sources disposition regional power market INTERCONNECTION
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Optimization of coproduction of ethyl acetate and n-butyl acetate by reactive distillation 被引量:1
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作者 田晖 赵素英 +1 位作者 郑辉东 黄智贤 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第4期667-674,共8页
Based on a previous investigation,a simulation model was used for optimization of coproduction of ethyl acetate and n-butyl acetate by reactive distillation.An experimental setup was established to verify the simulate... Based on a previous investigation,a simulation model was used for optimization of coproduction of ethyl acetate and n-butyl acetate by reactive distillation.An experimental setup was established to verify the simulated results.The effects of various operating variables,such as ethanol feed location,acetic acid feed location,feed stage of reaction mixture of acetic acid and n-butanol,reflux ratio of ethyl acetate reactive distillation column,and distillate to feed ratio of n-butyl acetate column,on the ethanol/n-butanol conversions,ethyl acetate/n-butyl acetate purity,and energy consumption were investigated.The optimal results in the simulation study are as follows:ethanol feed location,15th stage;acetic acid feed location,eighth stage;feed location of reaction mixture of acetic acid and n-butanol,eighth stage;reflux ratio of ethyl acetate reactive distillation column,2.0;and distillate to feed ratio of n-butyl acetate,0.6. 展开更多
关键词 Reactive distillationEthyl acetaten-Butyl acetateCoproductionSimulationOptimization
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