To improve acoustic performance of an air cleaner system,both experimental and theoretical studies were carried out.The air cleaner's acoustic numerical model was built by finite element methods(FEM).Acoustic param...To improve acoustic performance of an air cleaner system,both experimental and theoretical studies were carried out.The air cleaner's acoustic numerical model was built by finite element methods(FEM).Acoustic parameters of filter paper imported in the FEM model were calculated according to experiential formulas.Based on the models,the cleaner's acoustic character of transmission loss(TL) was computed.To verify the numerical results,TL results of the real air cleaner with or without filter paper were tested by four-microphone transferring function method.The experimental results show that the filter paper influence acoustic performance of the air cleaner significantly,especially in mid and high frequency band,and should be considered in numerical simulation.Comparisons between experimental and numerical results show that the numerical model is accurate enough to be used in multi-scheme acoustic optimization.Based on our study,TL results of two schemes were calculated and analyzed,which is useful to the air cleaner's final design decision.展开更多
In the study,the connotation and objectives of agricultural cleaner production were introduced firstly,and then the development status of agricultural cleaner production in China was analyzed,and the problems existing...In the study,the connotation and objectives of agricultural cleaner production were introduced firstly,and then the development status of agricultural cleaner production in China was analyzed,and the problems existing in the development of agricultural cleaner production were pointed out.From the strategy of agricultural sustainable development,the necessity and feasibility of implementing agricultural cleaner production in China were discussed.Finally,some related countermeasures were put forward according to the problems existing in the development of agricultural cleaner production,so as to provide theoretical references for the realization of agricultural sustainable development in China.展开更多
Curved coils constructed by flexible printed circuit board (PCB) or hand-wound Litz-wire have been steadily becoming popular due to its applicable potential on devices that have a curved body. Inductive Power Transfer...Curved coils constructed by flexible printed circuit board (PCB) or hand-wound Litz-wire have been steadily becoming popular due to its applicable potential on devices that have a curved body. Inductive Power Transfer (IPT) systems based on curved coils and flexible ferrite sheets may provide more flexible charging solutions for various electronic devices such as rice cookers and robot vacuum cleaners. Power repeaters are also used in IPT systems to extend wireless charging range by guiding magnetic fields to the receiving coil. The interaction of these three topics could be inspiring. In this paper, two adjustable power repeaters are applied to an IPT charging system with various curved receiving coils designed for vacuum cleaners. Two power repeaters share the identical structure as the Tx coil and could be rotated to mirror symmetrically. The input and output power are calculated by analyzing the equivalent circuit model. The self-inductance, mutual inductance, and coupling coefficient of the proposed system are obtained via finite element method simulation with variable rotating angles. Three typical IPT designs have also been simulated in ANSYS Maxwell and compared with the proposed magnetic design. The comparison indicates the enhancing feature of the passive power repeaters on coupling performance and the ability to guide the magnetic flux for better magnetic field coupling. Furthermore, two types of co-simulations defined by the power source via Simplorer are conducted to explore how much power could be transferred. The tuned system is shown to be able to provide about 32 W under 100 kHz operating frequency for charging the battery of a robot vacuum cleaner. The results from theoretical calculation and simulation align well with each other.展开更多
China National Petroleum Corporation(CNPC),Asia’s biggest oil and gas producer,will increase its investment in natural gas exploration and production,pipeline construction and gas sales in the coming decade,betting b...China National Petroleum Corporation(CNPC),Asia’s biggest oil and gas producer,will increase its investment in natural gas exploration and production,pipeline construction and gas sales in the coming decade,betting big on the country’s thirst for the clean fuel.The stateowned company,which currently allocates 70展开更多
Reporter: Deputy Director-General Mr. Zhang, I heard that the Motion Picture Association of America (MPAA) recently presented a complementary wood board to the Ministry of Culture of China. Could you tell the inside s...Reporter: Deputy Director-General Mr. Zhang, I heard that the Motion Picture Association of America (MPAA) recently presented a complementary wood board to the Ministry of Culture of China. Could you tell the inside story about it to our readers?Zhang Xinjian: On May 30, a delegation from MPAA led by its vice president paid a visit to my ministry and I had a talk with them on behalf of the Department of Cultural Market. During展开更多
In order to improve the flocculation efficiency of polydiallyldimethylammonium chloride(PDADMAC), high molecular weight PDADMAC should be prepared from high purity diallyldimethylammonium chloride(DADMAC) monomers...In order to improve the flocculation efficiency of polydiallyldimethylammonium chloride(PDADMAC), high molecular weight PDADMAC should be prepared from high purity diallyldimethylammonium chloride(DADMAC) monomers. In this paper, a cleaner method with microwave irradiation and alkali solidification was proposed for preparing high pure DADMAC by selective heating under low temperature, and the prepared high purity DADMAC is characterized using FTIR and atomic absorption spectrometry. The new method provides a solution to the key technical problem of PDADMAC synthesis. Comparing with the conventional methods, the results showed that the advantages of the novel synthesis include: (a) high purity DADMAC is improved from 57% to 71% ; (b) reaction time of tertiary amine preparation is shortened from 6 h to 7 min; (c) water instead of acetone was used as reaction medium; (d) toxic by-products, wastewater and waste gas are eliminated. Flocculant made from the synthesized high purity DADMAC monomers was proved more efficient in flocculation tests.展开更多
This paper reports results of the authors’ studies on the virtual design method used in the development of low noise intake system of I.C. engine. The resulting high pass-by noise at level above the legislative targe...This paper reports results of the authors’ studies on the virtual design method used in the development of low noise intake system of I.C. engine. The resulting high pass-by noise at level above the legislative target at full throttle when engine speed was around 5200 r/min necessitated a BEM-aided redesign task, following the typical process of design and development of an intake system. During the initial design, based on the acoustic theory and the requirements (1. The air flux of the redesigned should equal to or exceed the value of the original flux; 2. The filtering area must not be degraded), and considering the constraint of space in the engine compartment, total volume and rough internal dimensions were determined. During the detailed design, the exact internal dimensions of the air cleaner were determined, and an effective method was applied to improve the acoustic performance at low frequency. The predicted sound power of the intake system indicated that the objective of reducing the overall engine noise by minimizing intake system noise was achieved.展开更多
In order to promote cleaner production in China, a package of policy options was presented based on the identification of the barriers encountered in the CP demonstration project and the effectiveness and feasibility ...In order to promote cleaner production in China, a package of policy options was presented based on the identification of the barriers encountered in the CP demonstration project and the effectiveness and feasibility of policy options for the CP implementation were analyzed. Furthermore, the policy mechanism framework was given, which composes of compulsory, economic incentive, social pressure and supportive function. Finally, the implementation strategy of the policy mechanism, in which the emphasis will be changed from compulsory policy options towards economic and social pressure policy options, was proposed.展开更多
Based on systematical research on the conception evolution of ecological enterprise, theoretical and practical development of constructing ecological enterprise, the paper makes conclusion that ecological enterprises ...Based on systematical research on the conception evolution of ecological enterprise, theoretical and practical development of constructing ecological enterprise, the paper makes conclusion that ecological enterprises are developing into a new stage in which governments are launching some pilot projects about constructing ecological enterprises. And after that, governments should make policies to spread construction of ecological enterprises, to construct ecological enterprises in legal system and conforming to the standard as soon as possibly. 5o that, the basic units of ecological economy that fit to the conditions of China will be set up.展开更多
It is necessary for the sintering process to carry out cleaner production, which is also of great significance to the iron and steel enterprises of a long-flow process. According to the cleaner production standard rec...It is necessary for the sintering process to carry out cleaner production, which is also of great significance to the iron and steel enterprises of a long-flow process. According to the cleaner production standard recently issued by China' s Ministry of Environmental Protection, the research detailed in this study has analyzed and estimated the level of cleaner production at Baosteel in the aspects of technical equipment, resource and energy utilization, product quality, emissions, recycling and environmental management, etc. The research also expatiated some effective measures with which cleaner production can be carried out in Baosteel's sintering process, and discovered some potential opportunities of cleaner production.展开更多
Numerous studies evaluated the effects of end-of-pipe control environmental regulations(EER).However,few scholars discussed the effects of process management environmental regulations(PER),such as the China Cleaner Pr...Numerous studies evaluated the effects of end-of-pipe control environmental regulations(EER).However,few scholars discussed the effects of process management environmental regulations(PER),such as the China Cleaner Production Standards(CCPS)implemented by the country's Ministry of Ecology and Environment.Using data on China's manufacturing enterprises,this paper adopts the CCPS policies as quasi-natural experiments and uses differences-in-differences(DID)methods to analyze their effects on enterprise profitability and profit quality,respectively.The results show that:first,the CCPS significantly improve both profitability and profit quality;that is,the implementation of the environmental regulation policy plays a significant role in improving enterprise profit rates and cash flows.Second,for the profitability mediator effects,the short-term Porter effect of CCPS is not significant but shows the opposite during the lag period and significantly reduces the management cost and wage levels,comprehensively promoting enterprise profitability.Third,for the profit quality meditator effects,environmental regulations improve the enterprises'cash flow by reducing management costs and increasing government subsidies;however,its effect on bank credit subsidies is not significant.Fourth,for the moderator effects,the environmental regulations'effect on enterprises profitability and profit quality depends on the strategic interaction among local governments,the scale and ownership of the enterprise,and regional differences.That is,the strategic interaction weakens the effect of environmental regulations on enterprise performance.Environmental regulations have a stronger influence on profitability and profit quality for large-scale,state-owned,and coastal enterprises.展开更多
It is important to establish the evaluation system of the cleaner production of the mining enterprise, which canprovide the technical support and guidance for the cleaner production evaluation and facilitating the pro...It is important to establish the evaluation system of the cleaner production of the mining enterprise, which canprovide the technical support and guidance for the cleaner production evaluation and facilitating the promotion ofcleaner productive techniques so as to realize the integration of economic development and environmental protection.This paper, according to the characteristic of mining and Analytic Hierarchy Process (AHP), establishes the evaluationindex system, puts forward the overall quantitative evaluation method based on Fuzzy Mathematics and the experts’experience, and establishes the evaluation system of cleaner production. The main problems in cleaner production of themine are analyzed by calculation, and some countermeasures and suggestions are proposed.展开更多
Rapid urbanization and growing size of cities will have an increasing impact on the global environment in the 21st century. As an engine of urban development to drive economic growth and technological innovations, ind...Rapid urbanization and growing size of cities will have an increasing impact on the global environment in the 21st century. As an engine of urban development to drive economic growth and technological innovations, industry has moved its focus from controlling environmental hazards to stimulating sustainable industrial development throughout the entire product lifecycle. These process- and technology-driven innovations for industrial production are prerequisites for enhancement of urban environment and sustainable development of cities. In this review, problems of environment and resources scarcity associated with rapid urbanization are demonstrated. And, on the basis of expatiations on the concepts and policies of the cleaner production(CP) and other similar initiatives with the goal of preventing pollution at the source and of managing the raw material more efficiently, two different ways to link the practice of cleaner production in industrial sector with performance of urban environment are discussed in detail. Then, the introduction, practice and legislation of CP strategies in China are outlined, and possibility for China to develop CPC (Cleaner Practices for Cities) approaches in the demonstration cities is discussed. Finally, some suggestions on implementation of CPC strategies are put forward.展开更多
Wise Disk Cleaner是一款完全免费、非常傻瓜化的系统清理工具,该工具使用操作非常简单,可以帮助大家快速找出电脑内无用文件并将它们快速删除以释放更多空间,即便是菜鸟用户也可以通过该工具轻松胜任系统清理操作!安装完成后,选择...Wise Disk Cleaner是一款完全免费、非常傻瓜化的系统清理工具,该工具使用操作非常简单,可以帮助大家快速找出电脑内无用文件并将它们快速删除以释放更多空间,即便是菜鸟用户也可以通过该工具轻松胜任系统清理操作!安装完成后,选择立即启动Wise Disk CleanerFree,用户可以看到初始显示的主程序界面是英文显示。展开更多
The formation of kitchen greasy dirt was expounded, and the different types of kitchen cleaner and common products were introduced. At last, the development trend for kitchen cleaner was prospected.
基金Supported by Ministerial Level Advanced Research Foundation(1030021200706)
文摘To improve acoustic performance of an air cleaner system,both experimental and theoretical studies were carried out.The air cleaner's acoustic numerical model was built by finite element methods(FEM).Acoustic parameters of filter paper imported in the FEM model were calculated according to experiential formulas.Based on the models,the cleaner's acoustic character of transmission loss(TL) was computed.To verify the numerical results,TL results of the real air cleaner with or without filter paper were tested by four-microphone transferring function method.The experimental results show that the filter paper influence acoustic performance of the air cleaner significantly,especially in mid and high frequency band,and should be considered in numerical simulation.Comparisons between experimental and numerical results show that the numerical model is accurate enough to be used in multi-scheme acoustic optimization.Based on our study,TL results of two schemes were calculated and analyzed,which is useful to the air cleaner's final design decision.
基金Supported by Natural Science Foundation of Hainan Province (40879)Key Subject "Cartography and Geographic Information System"and "Natural Geography" of Hainan Normal University
文摘In the study,the connotation and objectives of agricultural cleaner production were introduced firstly,and then the development status of agricultural cleaner production in China was analyzed,and the problems existing in the development of agricultural cleaner production were pointed out.From the strategy of agricultural sustainable development,the necessity and feasibility of implementing agricultural cleaner production in China were discussed.Finally,some related countermeasures were put forward according to the problems existing in the development of agricultural cleaner production,so as to provide theoretical references for the realization of agricultural sustainable development in China.
文摘Curved coils constructed by flexible printed circuit board (PCB) or hand-wound Litz-wire have been steadily becoming popular due to its applicable potential on devices that have a curved body. Inductive Power Transfer (IPT) systems based on curved coils and flexible ferrite sheets may provide more flexible charging solutions for various electronic devices such as rice cookers and robot vacuum cleaners. Power repeaters are also used in IPT systems to extend wireless charging range by guiding magnetic fields to the receiving coil. The interaction of these three topics could be inspiring. In this paper, two adjustable power repeaters are applied to an IPT charging system with various curved receiving coils designed for vacuum cleaners. Two power repeaters share the identical structure as the Tx coil and could be rotated to mirror symmetrically. The input and output power are calculated by analyzing the equivalent circuit model. The self-inductance, mutual inductance, and coupling coefficient of the proposed system are obtained via finite element method simulation with variable rotating angles. Three typical IPT designs have also been simulated in ANSYS Maxwell and compared with the proposed magnetic design. The comparison indicates the enhancing feature of the passive power repeaters on coupling performance and the ability to guide the magnetic flux for better magnetic field coupling. Furthermore, two types of co-simulations defined by the power source via Simplorer are conducted to explore how much power could be transferred. The tuned system is shown to be able to provide about 32 W under 100 kHz operating frequency for charging the battery of a robot vacuum cleaner. The results from theoretical calculation and simulation align well with each other.
文摘China National Petroleum Corporation(CNPC),Asia’s biggest oil and gas producer,will increase its investment in natural gas exploration and production,pipeline construction and gas sales in the coming decade,betting big on the country’s thirst for the clean fuel.The stateowned company,which currently allocates 70
文摘Reporter: Deputy Director-General Mr. Zhang, I heard that the Motion Picture Association of America (MPAA) recently presented a complementary wood board to the Ministry of Culture of China. Could you tell the inside story about it to our readers?Zhang Xinjian: On May 30, a delegation from MPAA led by its vice president paid a visit to my ministry and I had a talk with them on behalf of the Department of Cultural Market. During
基金The National 10th Five-year Science and Technology Project of China(No.2002BA806b04-01B) and the Hi-Tech Research and Development Program(863) of China(No.2002AA601310)
文摘In order to improve the flocculation efficiency of polydiallyldimethylammonium chloride(PDADMAC), high molecular weight PDADMAC should be prepared from high purity diallyldimethylammonium chloride(DADMAC) monomers. In this paper, a cleaner method with microwave irradiation and alkali solidification was proposed for preparing high pure DADMAC by selective heating under low temperature, and the prepared high purity DADMAC is characterized using FTIR and atomic absorption spectrometry. The new method provides a solution to the key technical problem of PDADMAC synthesis. Comparing with the conventional methods, the results showed that the advantages of the novel synthesis include: (a) high purity DADMAC is improved from 57% to 71% ; (b) reaction time of tertiary amine preparation is shortened from 6 h to 7 min; (c) water instead of acetone was used as reaction medium; (d) toxic by-products, wastewater and waste gas are eliminated. Flocculant made from the synthesized high purity DADMAC monomers was proved more efficient in flocculation tests.
文摘This paper reports results of the authors’ studies on the virtual design method used in the development of low noise intake system of I.C. engine. The resulting high pass-by noise at level above the legislative target at full throttle when engine speed was around 5200 r/min necessitated a BEM-aided redesign task, following the typical process of design and development of an intake system. During the initial design, based on the acoustic theory and the requirements (1. The air flux of the redesigned should equal to or exceed the value of the original flux; 2. The filtering area must not be degraded), and considering the constraint of space in the engine compartment, total volume and rough internal dimensions were determined. During the detailed design, the exact internal dimensions of the air cleaner were determined, and an effective method was applied to improve the acoustic performance at low frequency. The predicted sound power of the intake system indicated that the objective of reducing the overall engine noise by minimizing intake system noise was achieved.
文摘In order to promote cleaner production in China, a package of policy options was presented based on the identification of the barriers encountered in the CP demonstration project and the effectiveness and feasibility of policy options for the CP implementation were analyzed. Furthermore, the policy mechanism framework was given, which composes of compulsory, economic incentive, social pressure and supportive function. Finally, the implementation strategy of the policy mechanism, in which the emphasis will be changed from compulsory policy options towards economic and social pressure policy options, was proposed.
文摘Based on systematical research on the conception evolution of ecological enterprise, theoretical and practical development of constructing ecological enterprise, the paper makes conclusion that ecological enterprises are developing into a new stage in which governments are launching some pilot projects about constructing ecological enterprises. And after that, governments should make policies to spread construction of ecological enterprises, to construct ecological enterprises in legal system and conforming to the standard as soon as possibly. 5o that, the basic units of ecological economy that fit to the conditions of China will be set up.
文摘It is necessary for the sintering process to carry out cleaner production, which is also of great significance to the iron and steel enterprises of a long-flow process. According to the cleaner production standard recently issued by China' s Ministry of Environmental Protection, the research detailed in this study has analyzed and estimated the level of cleaner production at Baosteel in the aspects of technical equipment, resource and energy utilization, product quality, emissions, recycling and environmental management, etc. The research also expatiated some effective measures with which cleaner production can be carried out in Baosteel's sintering process, and discovered some potential opportunities of cleaner production.
基金This study is supported by the Dengfeng Strategy of the key discipline construction project,“Environmental Technology Economics”,at the Chinese Academy of Social Sciences[Grant number.2017-ZXKHJ]the National Social Science Fund Youth Fund Project:“Research on the effect Mechanism and Heterogeneity of Environmental Regulation on the Formation of Zombie Enterprises”[Grant number.19CJY028]+1 种基金General Project funded by the National Social Science Foundation:Economic Mechanism Analysis and Management Innovation System Study in Rural Water Environment Issues[Grant Number.10BJY064]the project funded by the Basic Business Fund of High Learning Institutions of the Central Government:Obstacles and Countermeasures to Spatial Integration of Economic Growth:with Yangtze River Economic Belt as an example[Grant number.20156322020201].
文摘Numerous studies evaluated the effects of end-of-pipe control environmental regulations(EER).However,few scholars discussed the effects of process management environmental regulations(PER),such as the China Cleaner Production Standards(CCPS)implemented by the country's Ministry of Ecology and Environment.Using data on China's manufacturing enterprises,this paper adopts the CCPS policies as quasi-natural experiments and uses differences-in-differences(DID)methods to analyze their effects on enterprise profitability and profit quality,respectively.The results show that:first,the CCPS significantly improve both profitability and profit quality;that is,the implementation of the environmental regulation policy plays a significant role in improving enterprise profit rates and cash flows.Second,for the profitability mediator effects,the short-term Porter effect of CCPS is not significant but shows the opposite during the lag period and significantly reduces the management cost and wage levels,comprehensively promoting enterprise profitability.Third,for the profit quality meditator effects,environmental regulations improve the enterprises'cash flow by reducing management costs and increasing government subsidies;however,its effect on bank credit subsidies is not significant.Fourth,for the moderator effects,the environmental regulations'effect on enterprises profitability and profit quality depends on the strategic interaction among local governments,the scale and ownership of the enterprise,and regional differences.That is,the strategic interaction weakens the effect of environmental regulations on enterprise performance.Environmental regulations have a stronger influence on profitability and profit quality for large-scale,state-owned,and coastal enterprises.
文摘It is important to establish the evaluation system of the cleaner production of the mining enterprise, which canprovide the technical support and guidance for the cleaner production evaluation and facilitating the promotion ofcleaner productive techniques so as to realize the integration of economic development and environmental protection.This paper, according to the characteristic of mining and Analytic Hierarchy Process (AHP), establishes the evaluationindex system, puts forward the overall quantitative evaluation method based on Fuzzy Mathematics and the experts’experience, and establishes the evaluation system of cleaner production. The main problems in cleaner production of themine are analyzed by calculation, and some countermeasures and suggestions are proposed.
基金Under the auspices of Knowledge Innovation Project of Chinese Academy of Sciences (No. KZCX3-SW-427) Ma-jor State Basic Research Program of China (No. G1999045707)
文摘Rapid urbanization and growing size of cities will have an increasing impact on the global environment in the 21st century. As an engine of urban development to drive economic growth and technological innovations, industry has moved its focus from controlling environmental hazards to stimulating sustainable industrial development throughout the entire product lifecycle. These process- and technology-driven innovations for industrial production are prerequisites for enhancement of urban environment and sustainable development of cities. In this review, problems of environment and resources scarcity associated with rapid urbanization are demonstrated. And, on the basis of expatiations on the concepts and policies of the cleaner production(CP) and other similar initiatives with the goal of preventing pollution at the source and of managing the raw material more efficiently, two different ways to link the practice of cleaner production in industrial sector with performance of urban environment are discussed in detail. Then, the introduction, practice and legislation of CP strategies in China are outlined, and possibility for China to develop CPC (Cleaner Practices for Cities) approaches in the demonstration cities is discussed. Finally, some suggestions on implementation of CPC strategies are put forward.
文摘Wise Disk Cleaner是一款完全免费、非常傻瓜化的系统清理工具,该工具使用操作非常简单,可以帮助大家快速找出电脑内无用文件并将它们快速删除以释放更多空间,即便是菜鸟用户也可以通过该工具轻松胜任系统清理操作!安装完成后,选择立即启动Wise Disk CleanerFree,用户可以看到初始显示的主程序界面是英文显示。
基金National Natural Science Foundation of China(NSFC)(No.41171250)
文摘The formation of kitchen greasy dirt was expounded, and the different types of kitchen cleaner and common products were introduced. At last, the development trend for kitchen cleaner was prospected.