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The Separation of Powers from Functions and the Establishment of a New Structure of Management and Operation of State-owned Assets
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作者 Zhou Li-qun Ph. D. of Economics. Associate Professor of Institute of Economics of NANKAI UNIVERSITY. Deputy Dean of College of Economics, NANKAI UNIVERSITY 《南开经济研究》 CSSCI 北大核心 1994年第S3期13-18,共6页
The development of the socialist market economy demands the furtherintensification of the reform of the management operating system (MOS)of the state-owned assets, the strengthening of the efficiency in the man-agemen... The development of the socialist market economy demands the furtherintensification of the reform of the management operating system (MOS)of the state-owned assets, the strengthening of the efficiency in the man-agement of state-owned assets,and the improvement of the operating bene- 展开更多
关键词 the separation of Powers from Functions and the Establishment of a New Structure of Management and operation of State-owned Assets
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Fuzzy self-tuning PID control of the operation temperatures in a two-staged membrane separation process 被引量:8
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作者 Lei Wang Wencai Du +1 位作者 Hai Wang Hong Wu 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第4期409-414,共6页
A two-staged membrane separation process for hydrogen recovery from refinery gases is introduced. The principle of the gas membrane separation process and the influence of the operation temperatures are analyzed. As t... A two-staged membrane separation process for hydrogen recovery from refinery gases is introduced. The principle of the gas membrane separation process and the influence of the operation temperatures are analyzed. As the conventional PID controller is difficult to make the operation temperatures steady, a fuzzy self-tuning PID control algorithm is proposed. The application shows that the algorithm is effective, the operation temperatures of both stages can be controlled steadily, and the operation flexibility and adaptability of the hydrogen recovery unit are enhanced with safety. This study lays a foundation to optimize the control of the membrane separation process and thus ensure the membrane performance. 展开更多
关键词 membrane separation hydrogen recovery operation temperature fuzzy self-tuning PID control
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Radial Basis Function Neural Networks-Based Modeling of the Membrane Separation Process: Hydrogen Recovery from Refinery Gases 被引量:6
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作者 Lei Wang Cheng Shao +1 位作者 Hai Wang Hong Wu 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2006年第3期230-234,共5页
Membrane technology has found wide applications in the petrochemical industry, mainly in the purification and recovery of the hydrogen resources. Accurate prediction of the membrane separation performance plays an imp... Membrane technology has found wide applications in the petrochemical industry, mainly in the purification and recovery of the hydrogen resources. Accurate prediction of the membrane separation performance plays an important role in carrying out advanced process control (APC). For the first time, a soft-sensor model for the membrane separation process has been established based on the radial basis function (RBF) neural networks. The main performance parameters, i.e, permeate hydrogen concentration, permeate gas flux, and residue hydrogen concentration, are estimated quantitatively by measuring the operating temperature, feed-side pressure, permeate-side pressure, residue-side pressure, feed-gas flux, and feed-hydrogen concentration excluding flow structure, membrane parameters, and other compositions. The predicted results can gain the desired effects. The effectiveness of this novel approach lays a foundation for integrating control technology and optimizing the operation of the gas membrane separation process. 展开更多
关键词 membrane separation hydrogen recovery soft sensor RBF neural networks REFINERY operation optimization
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A review of state-of-the-art processing operations in coal preparation 被引量:7
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作者 Noble Aaron Luttrell Gerald H. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第4期511-521,共11页
Coal preparation is an integral part of the coal commodity supply chain. This stage of post-mining, pre-utilization beneficiation uses low-cost separation technologies to remove unwanted mineral matter and moisture wh... Coal preparation is an integral part of the coal commodity supply chain. This stage of post-mining, pre-utilization beneficiation uses low-cost separation technologies to remove unwanted mineral matter and moisture which hinder the value of the coal product. Coal preparation plants typically employ several parallel circuits of cleaning and dewatering operations, with each circuit designed to optimally treat a specific size range of coal. Recent innovations in coal preparation have increased the efficiency and capac- ity of individual unit operations while reinforcing the standard parallel cleaning approach. This article, which describes the historical influences and state-of-the-art design for the various coal preparation unit operations, is organized to distinguish between coarse/intermediate coal cleaning and fine/ultrafine coal cleaning. Size reduction, screening, classification, cleaning, dewatering, waste disposal unit operations are particularly highlighted, with a special focus on the LI.S. design philosophy. Notable differences between the U.S. and international operations are described as appropriate. 展开更多
关键词 Coal preparation Coal supply chain Unit operations Particulate separations Tailings disposal
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Separation process study of liquid phase catalytic exchange reaction based on the Pt/C/PTFE catalysts 被引量:2
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作者 Peilong Li Li Guo +7 位作者 Renjin Xiong Junhong Luo Ming Wen Yong Yao Zhi Zhang Jiangfeng Song Yan Shi Tao Tang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第8期1837-1845,共9页
The liquid phase catalytic exchange(LPCE) reaction is an effective process for heavy water detritiation and production of deuterium-depleted potable water. In the current study, hydrophobic carbon-supported platinum c... The liquid phase catalytic exchange(LPCE) reaction is an effective process for heavy water detritiation and production of deuterium-depleted potable water. In the current study, hydrophobic carbon-supported platinum catalysts(Pt/C/PTFE) with high efficiency as reported previously for LPCE were prepared and comprehensive performance evaluation method is applied to evaluate the separation behaviors of LPCE systematically. Experimental results indicate that the optimum reaction temperature of 60–80℃ and the molar feed ratio G/L of 1.5–2.5 would lead to higher separation efficiencies. As to the packing method, a random packing mode with a packing ratio of hydrophobic catalysts 0.25 is recommended. In addition, thermodynamic analysis corresponds well with experimental results under lower temperature and G/L, while the suppression of kinetic factors should not be neglected when T > 80℃ and G/L > 1.5. 展开更多
关键词 Liquid phase CATALYTIC exchange(LPCE) HYDROPHOBIC carbon-supported PLATINUM CATALYSTS separation behaviors Optimal operating condition Water DETRITIATION
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Remarks on the Riesz Separation Property of the Linear Span of Positive Compact Operators 被引量:1
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作者 陈滋利 《Journal of Southwest Jiaotong University(English Edition)》 2005年第2期182-184,共3页
It is proven that there exists a Dedekind complete Banach lattice E such that the linear spans/f (E) and IV (E) of positive compact and positive weakly compact operators on E fails to possess the Riesz separation ... It is proven that there exists a Dedekind complete Banach lattice E such that the linear spans/f (E) and IV (E) of positive compact and positive weakly compact operators on E fails to possess the Riesz separation property. 展开更多
关键词 Banach lattice Dcdekind complete Compact operator Riesz separation property
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Industrial Progress:New Energy-Efficient Absorbents for the CO_(2) Separation from Natural Gas,Syngas and Flue Gas 被引量:1
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作者 Jorn Rolker Matthias Seiler 《Advances in Chemical Engineering and Science》 2011年第4期280-288,共9页
The CO2 separation from natural gas, syngas or flue gas represents an important industrial field of applications. An economic and energy-efficient CO2 separation from these gas streams is a prerequisite for sustainabl... The CO2 separation from natural gas, syngas or flue gas represents an important industrial field of applications. An economic and energy-efficient CO2 separation from these gas streams is a prerequisite for sustainable industry contributions to the megatrends resource efficiency and globalization of technologies. One way of reducing operational expenditure for these separation processes is the development of better performing CO2 absorbents. Although a number of absorbents for the separation of CO2 from process gas streams exist, the need for the development of CO2 absorbents with an improved absorption performance, less corrosion and foaming, no nitrosamine formation, lower energy requirement and therefore less operational expenditure remains. Recent industrial activities have led to the development of novel high-performance CO2 scrubbing agents that can be employed in numerous industrial processes such as natural gas treatment, purification of syngas and the scrubbing of flue gas. The objective of this paper is to introduce these new high-performance scrubbing agents and to compare their performance with other state-of-the-art absorbents. It turned out, that the evaluated absorbents offer high cyclic capacities in the range of 2.4 to 2.6 mol CO2/kg absorbent and low absorption enthalpies (–30 kJ/mol) allowing for distinctive savings in the regeneration energy of the absorbent. Calculations with the modified Kremser model resulted in a reduction of the specific reboiler heat duty of 55%. Furthermore, the absorbents are less corrosive than standard amines as indicated by the measured corrosion rates of 0.21 mm/y versus 1.18 mm/y for a piperazine/methyldiethanolamine mixture. Based on new experimental results it is shown how substantial savings in operational and capital expenditure can be realized due to favorable absorbent properties. The novel high-performance CO2 system solutions meet recent industrial absorbent requirements and allow for more efficient or new CO2 separation processes. 展开更多
关键词 ABSORBENT CO_(2) Energy Efficiency Sustainability operational Expenditure separation Capture
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The Second Separation Test of LM-5B Payload Fairing Completed
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作者 QIN Jianli 《Aerospace China》 2015年第2期64-64,共1页
The Beijing Institute of Structural and Environmental Engineering has completed the second separation test of LM-5B payload fairing in Tianjin successfully.The fairing separated perfectly and was recovered safely and ... The Beijing Institute of Structural and Environmental Engineering has completed the second separation test of LM-5B payload fairing in Tianjin successfully.The fairing separated perfectly and was recovered safely and stably.The control and measurement system for testing operated normally during the test. 展开更多
关键词 PAYLOAD perfectly completed safely TIANJIN operated recovered normally SEPARATED COMPLETION
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Accuracy analysis of the optimal separable approximation method of one-way wave migration
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作者 杜淑媛 陈景波 刘洪 《Applied Geophysics》 SCIE CSCD 2011年第4期328-336,371,372,共11页
An approximation for the one-way wave operator takes the form of separated space and wave-number variables and makes it possible to use the FFT, which results in a great improvement in the computational efficiency. Fr... An approximation for the one-way wave operator takes the form of separated space and wave-number variables and makes it possible to use the FFT, which results in a great improvement in the computational efficiency. From the function approximation perspective, the OSA method shares the same separable approximation format to the one-way wave operator as other separable approximation methods but it is the only global function approximation among these methods. This leads to a difference in the phase error curve, impulse response, and migration result from other separable approximation methods. The difference is that the OSA method has higher accuracy, and the sensitivity to the velocity variation declines with increasing order. 展开更多
关键词 one-way wave operator MIGRATION separable approximation optimal separable approximation
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Experimental Study on Three-phase Separation of Oily Sludge 被引量:2
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作者 Jia Min Wang Lei +2 位作者 Zhang Xu Wang Hui Si Huanhuan 《Meteorological and Environmental Research》 CAS 2017年第6期47-49,共3页
Three-phase centrifuge was used to process oily sludge,and the requirement of mud,oil and water three-phase separation was satisfied through the optimization of parameters. The results showed that when the input quant... Three-phase centrifuge was used to process oily sludge,and the requirement of mud,oil and water three-phase separation was satisfied through the optimization of parameters. The results showed that when the input quantity was lower than 5 m^3/h,the optimal operation parameters of the three-phase centrifuge are shown as follows: the frequency of the main motor and vice motor was 33 and 30 Hz respectively,and the flocculant flow was 0. 7 m^3/h,while the oily sludge temperature was 55 ℃. Water content in the separated sludge decreased from 98% to lower than 70%,and the goal of reduction and harmless treatment of oily sludge could be achieved,which could provide essential conditions for subsequent resource utilization and could be used to guide industrial production. 展开更多
关键词 Oily SLUDGE THREE-PHASE separation operation PARAMETERS Reduction HARMLESS RECLAMATION
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Evolutionary Computation for Realizing Distillation Separation Sequence Optimization Synthesis 被引量:2
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作者 Dong Hongguang Qin Limin Wang Kefeng Yao Pingjing 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2005年第4期52-59,共8页
Evolutionary algorithm is applied for distillation separation sequence optimization synthesis problems with combination explosion. The binary tree data structure is used to describe the distillation separation sequenc... Evolutionary algorithm is applied for distillation separation sequence optimization synthesis problems with combination explosion. The binary tree data structure is used to describe the distillation separation sequence, and it is directly applied as the coding method. Genetic operators, which ensure to prohibit illegal filial generations completely, are designed by using the method of graph theory. The crossover operator based on a single parent or two parents is designed successfully. The example shows that the average ratio of search space from evolutionary algorithm with two-parent genetic operation is lower, whereas the rate of successful minimizations from evolutionary algorithm with single parent genetic operation is higher. 展开更多
关键词 evolutionary algorithm coding method based on the binary tree crossover operator mutation operator distillation separation sequence optimization synthesis
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THE EXTENSION THEOREMS OF CONE LINEAR OPERATORS
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作者 盛宝怀 刘三阳 毛华 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第1期71-78,共8页
A kind of cone separation theorems is established, by which the extension theorems for cone linear continuous operators are developed. As an application, the extension theorem for positive linear continuous operators ... A kind of cone separation theorems is established, by which the extension theorems for cone linear continuous operators are developed. As an application, the extension theorem for positive linear continuous operators is given. 展开更多
关键词 cone separation theorem cone linear operator extension theorem separation theorems
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Separation of Waves by Interpolation Method
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作者 孙鹤泉 王永学 《海洋工程:英文版》 2003年第1期123-132,共10页
The separation of waves by an interpolation method is presented in detail. The composite wave sequences measured with two wave gauges in the wave flume are separated very quickly into two series of incident and reflec... The separation of waves by an interpolation method is presented in detail. The composite wave sequences measured with two wave gauges in the wave flume are separated very quickly into two series of incident and reflected waves in time domain via the simple interpolation and difference operations. Then, the reflection coefficient can be estimated easily and accurately without calculation of wave heights and phases. The intial phase of reflection can also be detected easily for improvement of the accuracy of calculation. The present method is applicable to both regular and irregular trains of waves based on the linear wave theory which are proved to be accurate through numerical sample tests. Physical experiments are conducted and compared with Goda′s method and analytical method with satisfactory results. Furthermore, the present method can be used for the absorbing wave maker to extract reflected waves in real time. 展开更多
关键词 separation of waves reflection coefficient INTERPOLATION difference operation
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A Novel Operation Policy for Dilute Component Separation-Quasi-batch Distillation
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作者 罗祎青 袁希钢 +1 位作者 杨祖杰 刘春江 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第3期338-342,共5页
A new operation policy--quasi-batch distillation for recovering infinitesimal amounts species existing in a mixture is presented. In quasi-batch distillation operation, feed is introduced with a constant flow rate ont... A new operation policy--quasi-batch distillation for recovering infinitesimal amounts species existing in a mixture is presented. In quasi-batch distillation operation, feed is introduced with a constant flow rate onto the feed stage of the column, and the flow rate of the distillate is the same as that of the feed, whereas the bottom product is withdrawn periodically. The behavior of quasi-batch distillation is simulated and analyzed through an example on heavy water separation. Comparing with continuous or batch distillation, the new operation policy is more reliable and efficient to achieve higher recovery of dilute component. This is especially suitable for separating small amount of precious species from large amount of raw material. 展开更多
关键词 quasi-batch distillation isotope separation operation policy
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Necessary and Sufficient Conditions for the Separability and the R-Separability of the Irrotational Stokes Equation and Applications
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作者 Eleftherios Protopapas Maria Hadjinicolaou 《Journal of Applied Mathematics and Physics》 2020年第11期2379-2401,共23页
In the present manuscript, we formulate and prove rigorously, necessary and sufficient conditions for all kinds of separation of variables that a solution of the irrotational Stokes equation may exhibit, in any orthog... In the present manuscript, we formulate and prove rigorously, necessary and sufficient conditions for all kinds of separation of variables that a solution of the irrotational Stokes equation may exhibit, in any orthogonal axisymmetric system, namely: simple separation and R-separation. These conditions may serve as a road map for obtaining the corresponding solution space of the irrotational Stokes equation, in any orthogonal axisymmetric coordinate system. Additionally, we investigate how the inversion of the coordinate system, with respect to a sphere, affects the type of separation. Specifically, we prove that if the irrotational Stokes equation separates variables in an axisymmetric coordinate system, then it R-separates variables in the corresponding inverted coordinate system. This is a quite useful outcome since it allows the derivation of solutions for a problem, from the knowledge of the solution of the same problem in the inverted geometry and vice-versa. Furthermore, as an illustration, we derive the eigenfunctions of the irrotational Stokes equation governing the flow past oblate spheroid particles and inverted oblate spheroidal particles. 展开更多
关键词 Axisymmetric Flow Stokes Operator Analytical Solution separation and R-separation of Variables Axisymmetric Orthogonal Coordinate Systems
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Devolution of Sta. Ana Davao Port: Then and Now
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作者 Saidamin P. Bagolong Neil John T. Audan Angelica Faye G. Cameguing Sunshine B. Cordero 《International Relations and Diplomacy》 2014年第10期691-696,共6页
Better seaport operation is one of the indicators that a city is achieving its goals towards progress and development. The Sta. Ana Davao Port for example is one of the many seaports in Region XI that caters to thousa... Better seaport operation is one of the indicators that a city is achieving its goals towards progress and development. The Sta. Ana Davao Port for example is one of the many seaports in Region XI that caters to thousands of passengers going from one terminal to another and from one island to another. In this study, it will revisit the status of Sta. Davao Port from the time when it was devolved from the national goverrmaent under Philippine Ports Authority (PPA) to local government of Davao City. The devolution was in accordance with the Memorandum of Agreement by two parties, which clearly stipulates the full-control of operation of the local government of Davao City with an end view of bringing more investors, tourist hubs and other business related concerns. This study utilized descriptive-evaluative method using interview guide question as a qualitative approach in gathering data. The participants were the former employees of the PPA and the current management of Sta. Ana Davao Port under the local government. Data gathered were analyzed using Nvivo software for qualitative research and content analysis to obtain factual information direct from the participants. It was found out that most of the employees agreed that the office needs improvement in terms of physical, financial and human aspects. For several years, the passengers of both local and foreign shipping lines were complaining on its limited berthing capacities, saturated container yards and even worse the collapse of the berthing area which resulted to the delay of transactions in the operation of the vessels. In spite of employees claimed that prior to devolution of Sta. Ana Davao Port to the local government of Davao City, the operation was well-managed and maintained, thereby resulted to passengers' satisfaction. Thus, the researchers aimed to provide an action plan as basis by the management of the Sta. Davao Port to achieve its vision, missions and goals. 展开更多
关键词 port operation Sta. Ana Davao Port devolution public administration local government Davao Philippines
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Design and Operation of Municipal Rain and Sewage United Pumping Station
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作者 Ting Ting Liu 《Journal of Architectural Research and Development》 2023年第4期51-56,共6页
In the process of designing a municipal rainwater and sewage pumping station,it is necessary to accurately grasp the design points,reasonably determine the scale of the rainwater and sewage pumping station,scientifica... In the process of designing a municipal rainwater and sewage pumping station,it is necessary to accurately grasp the design points,reasonably determine the scale of the rainwater and sewage pumping station,scientifically select the location and layout,and select materials reasonably.After completing the process design of the municipal rainwater and sewage pumping station and putting it into operation,in order to ensure the normal and stable operation of the pumping station,it is necessary to focus on strengthening the operation and management of diving equipment,cleaning equipment,and electromechanical equipment.The author analyzes the key points and specific design path of the process design of municipal rainwater and sewage pumping stations,and puts forward effective strategies for operation management,hoping to contribute to the scientific design and stable operation of municipal rainwater and sewage pumping stations. 展开更多
关键词 Municipal administration Rainwater and sewage united pumping stations Design path operation management
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First membrane unit for separating CO_2 from natural gas operational
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《Bulletin of the Chinese Academy of Sciences》 2007年第1期57-57,共1页
After a more-than-two-week trial operation, a new membrane unit based on the technology developed by researchers from the CAS Dalian Institute of
关键词 CO First membrane unit for separating CO2 from natural gas operational
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CFD numerical simulation of flow velocity characteristics of hydrocyclone 被引量:9
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作者 高淑玲 魏德洲 +3 位作者 刘文刚 马龙秋 卢涛 张瑞洋 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2783-2789,共7页
A CFD based numerical simulation of flow velocity of hydrocyclone was conducted with different structural and operational parameters to investigate its distribution characteristics and influencing mechanism. The resul... A CFD based numerical simulation of flow velocity of hydrocyclone was conducted with different structural and operational parameters to investigate its distribution characteristics and influencing mechanism. The results show there exist several unsymmetrical envelopes of equal vertical velocities in both upward inner flows and downward outer flows in the hydrocyclone, and the cone angle and apex diameter have remarkable influence on the vertical location of the cone bottom of the envelope of zero vertical velocity. It is also found that the tangential velocity isolines exist in the horizontal planes located in the effective separation region of hydrocyclone. The increase of feed pressure has almost no effect on the distribution characteristics of both vertical velocity and tangential velocity in hydrocyclone, but the magnitude and gradient of tangential velocity are increased obviously to make the motion velocity of high density particles to the wall increased and to make the cyclonic separation effect improved. 展开更多
关键词 numerical simulation HYDROCYCLONE flow velocity characteristics structural parameter operational parameter cyclonic separation effect
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国有资产改革对自然资源资产“两权”分离的启示与借鉴
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作者 林霖 黄志豪 +4 位作者 康琴 陈丹 张敏 王珂 虞舟鲁 《生态经济》 北大核心 2025年第1期195-200,共6页
我国国有资产管理体制经过了从统一到分散再到统一的改革历程。在此过程中,国务院设立国有资产监督管理委员会,并逐步推动国有资产管理方式从以管企业为主向以管资本为主转变,探索了国有资产所有权与监管权“两权”分离的路径。鉴于自... 我国国有资产管理体制经过了从统一到分散再到统一的改革历程。在此过程中,国务院设立国有资产监督管理委员会,并逐步推动国有资产管理方式从以管企业为主向以管资本为主转变,探索了国有资产所有权与监管权“两权”分离的路径。鉴于自然资源资产管理与国有资产管理存在较强相似性,国有资产投资运营公司在促进国有资产“两权”分离中的关键作用,为自然资源资产所有权与监管权的分离提供了重要启示和借鉴。自然资源资产管理在完成委托代理机制试点后,建议管理方式由“资源管理”逐步转向“资产管理”,授权设立自然资源投资运营公司,以实现自然资源资产“两权”的有效分离,从“自然资源部门—自然资源资产”的二级管理体制转变为“自然资源部门—自然资源投资运营公司—自然资源资产”的三级管理体制,以期为推进自然资源资产的有效监管和资产增值提供改革思路与参考。 展开更多
关键词 国有资产改革 自然资源资产 “两权”分离 投资运营公司
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