This paper examines project⁃based policies and regulations implemented globally to control and mitigate emissions from diesel⁃powered construction equipment.This study systematically reviews and analyzes various manag...This paper examines project⁃based policies and regulations implemented globally to control and mitigate emissions from diesel⁃powered construction equipment.This study systematically reviews and analyzes various managerial,regulatory,and technical measures adopted across countries and regions,mostly of advanced economy.Key strategies of control include setting emission thresholds,idling restrictions,perform remote online monitoring,operational time limits,setting low emission zones,and enforced registration systems.The review highlights the rationale,implementation details,and experiences gained from these localized approaches,reduces localized emission sources,improve urban air quality and environmental management efficiency.展开更多
An improved numerical simulation method is presented to calculate the downhole temperature distribution for multiple pay zones in producing oil wells. Based on hydrodynamics and heat transfer theory, a 2-D temperature...An improved numerical simulation method is presented to calculate the downhole temperature distribution for multiple pay zones in producing oil wells. Based on hydrodynamics and heat transfer theory, a 2-D temperature field model in cylindrical coordinates is developed. In the model, we considered general heat conduction as well as the heat convection due to fluid flow from porous formation to the borehole. We also take into account the fluid velocity variation in the wellbore due to multiple pay zones. We present coupled boundary conditions at the interfaces between the wellbore and adjacent formation, the wellbore and pay zone, and the pay zone and adjacent formation. Finally, an alternating direction implicit difference method （ADI） is used to solve the temperature model for the downhole temperature distribution. The comparison of modeled temperature curve with actual temperature log indicates that simulation result is in general quite similar to the actual temperature log. We found that the total production rate, production time, porosity, thickness of pay zones, and geothermal gradient, all have effects on the downhole temperature distribution.展开更多
The processes of flooding—water flooding, polymer flooding and ternary combination flooding—were simulated respectively on a 2-D positive rhythm profile geological model by using the ASP numerical modeling softw...The processes of flooding—water flooding, polymer flooding and ternary combination flooding—were simulated respectively on a 2-D positive rhythm profile geological model by using the ASP numerical modeling software developed by RIPED (Yuan, et al. 1995). The recovery coefficient, remaining oil saturation, sweep efficiency and displacement efficiency were calculated and correlated layer by layer. The results show that the sweep efficiency and displacement efficiency work different effects on different layers in the severely heterogeneous reservoir. The study shows that the displacement efficiency and sweep efficiency play different roles in different layers for severely heterogeneous reservoirs. The displacement efficiency contributes mainly to the high permeability zones, the sweep efficiency to the low permeability zones, both of which contribute to the middle permeable zones. To improve the sweep efficiency in the low permeability zones is of significance for enhancing the whole recovery of the reservoir. It is an important path for improving the effectiveness of chemical flooding in the severely heterogeneous reservoirs to inject ternary combination slug after profile control.展开更多
The research explored the extraction techniques of organic solvents of Antarctic kril oil and the effects of freezing temperature, extractant proportion, ex-traction time, drying temperature and ratio of material and ...The research explored the extraction techniques of organic solvents of Antarctic kril oil and the effects of freezing temperature, extractant proportion, ex-traction time, drying temperature and ratio of material and liquid on extraction ratio of Antarctic kril oil. Based on single-factor experiments, optimal extraction conditions were concluded as per response surface methodology, as fol ows： freezing tempera-ture at -38.5 ℃, the ratio of material and liquid at 1 g：6.7 ml, and drying tempera-ture at 66.8 ℃, where the yield rate of crude oil reached 13.71%.展开更多
Highly acidic crude oil is thermally soaked to investigate how the temperature and time involved affect the removal of organic acid in feedstock. Experimental results indicate that thermal treatment is an effective a...Highly acidic crude oil is thermally soaked to investigate how the temperature and time involved affect the removal of organic acid in feedstock. Experimental results indicate that thermal treatment is an effective approach to decreasing acidity and the acid removal rate reaches 80%. Temperature is one of the main factors that determine the acid removal reaction. When the temperature ranges from 420oC to 440oC, the acid removal rate increases with the rise of the reaction temperature, but the increase slows down gradually. At the reaction temperature below 440oC, the long reaction time favors the acid removal. The cracking and polymerization of hydrocarbon molecules take place so that the properties of the crude oil change at the same time when the highly acidic crude is thermally treated.展开更多
[Objective] The research aimed to optimize laboratory artificial rearing methods for Plutella xylostella L. and to select out effective insecticides against this pest species. [Method] Brassica chinensis seedlings wer...[Objective] The research aimed to optimize laboratory artificial rearing methods for Plutella xylostella L. and to select out effective insecticides against this pest species. [Method] Brassica chinensis seedlings were cultivated in the laboratory at （25±1）℃, 60-75% RH, and a photoperiod of 14：10 （L：D） h. The green blow molding papers were used to collect eggs, and Brassica oleracea seedlings were cultivated to breed Plutella xylostella L. until the insects were ready for use. Mean-while, the susceptibility of 3rd instar larvae of Plutella xylostella L. to five types of insecticides was tested by leaf-dipping method. [Result] Plutella xylostella L. larvae were found well-grown and uniform in developmental stages with average pupa weight of 5.4 mg, pupa emergence percentage of 94.0 % and egg number of 135.1 per female. The LCso values of 3rd instar Plutella xylostella L. larvae against 200 g/L chlorantraniliprole SC, 20% flubendiamide WG, 150 g/L indoxacarb EC, 200 g/L tebufenozide SC and 1.8% abamectin EC, were 0.152, 0.223, 1.151, 93.340 and 0.128 mg/L, respectively. [Conclusion] This rearing method is easy to be implemented and of great practicality, suitable for mass propagation of P. xylostella L. Abamectin, chlorantraniliprole and flubendiamide showed high insecticidal activities, so these three insecticides can be used alternately for the field prevention and control of Plutella xylostella L.展开更多
On July 8th, 2005, China＇s largest integrated oil refining and chemical joint-venture project was officially launched in Quanzhou, Fujian Province, indicating that another petrochemical base is growing up following S...On July 8th, 2005, China＇s largest integrated oil refining and chemical joint-venture project was officially launched in Quanzhou, Fujian Province, indicating that another petrochemical base is growing up following Sinopec Qilu Petrochemical Company, Sinopec Beijing Yanhua Petrochemical Co. Ltd,展开更多
E-commerce is known as the most advanced business mode, being the new point for global economic growth in 21 century. Comparing to the traditional purchase mode, E-commerce is available for reducing the purchasing cos...E-commerce is known as the most advanced business mode, being the new point for global economic growth in 21 century. Comparing to the traditional purchase mode, E-commerce is available for reducing the purchasing cost and improving the working efficiency, thus lifting the whole benefit for the company through centralized purchasing.展开更多
The trial of oil displacement driven by natural gas injection in China has been successfully accomplished recently for the first time in Zhongyuan Oilfield, Henan Province. This technology is ready for oilfield applic...The trial of oil displacement driven by natural gas injection in China has been successfully accomplished recently for the first time in Zhongyuan Oilfield, Henan Province. This technology is ready for oilfield application in July.展开更多
基金Research Grants Council of the Hong Kong Special Administrative Region,China(U15239024)。
文摘This paper examines project⁃based policies and regulations implemented globally to control and mitigate emissions from diesel⁃powered construction equipment.This study systematically reviews and analyzes various managerial,regulatory,and technical measures adopted across countries and regions,mostly of advanced economy.Key strategies of control include setting emission thresholds,idling restrictions,perform remote online monitoring,operational time limits,setting low emission zones,and enforced registration systems.The review highlights the rationale,implementation details,and experiences gained from these localized approaches,reduces localized emission sources,improve urban air quality and environmental management efficiency.
基金sponsored by the National Nature Science Foundation of China (Grant No. 40830424).
文摘An improved numerical simulation method is presented to calculate the downhole temperature distribution for multiple pay zones in producing oil wells. Based on hydrodynamics and heat transfer theory, a 2-D temperature field model in cylindrical coordinates is developed. In the model, we considered general heat conduction as well as the heat convection due to fluid flow from porous formation to the borehole. We also take into account the fluid velocity variation in the wellbore due to multiple pay zones. We present coupled boundary conditions at the interfaces between the wellbore and adjacent formation, the wellbore and pay zone, and the pay zone and adjacent formation. Finally, an alternating direction implicit difference method （ADI） is used to solve the temperature model for the downhole temperature distribution. The comparison of modeled temperature curve with actual temperature log indicates that simulation result is in general quite similar to the actual temperature log. We found that the total production rate, production time, porosity, thickness of pay zones, and geothermal gradient, all have effects on the downhole temperature distribution.
基金This project is supported by the China National Key Basis Research Project (No: G1999022512)
文摘The processes of flooding—water flooding, polymer flooding and ternary combination flooding—were simulated respectively on a 2-D positive rhythm profile geological model by using the ASP numerical modeling software developed by RIPED (Yuan, et al. 1995). The recovery coefficient, remaining oil saturation, sweep efficiency and displacement efficiency were calculated and correlated layer by layer. The results show that the sweep efficiency and displacement efficiency work different effects on different layers in the severely heterogeneous reservoir. The study shows that the displacement efficiency and sweep efficiency play different roles in different layers for severely heterogeneous reservoirs. The displacement efficiency contributes mainly to the high permeability zones, the sweep efficiency to the low permeability zones, both of which contribute to the middle permeable zones. To improve the sweep efficiency in the low permeability zones is of significance for enhancing the whole recovery of the reservoir. It is an important path for improving the effectiveness of chemical flooding in the severely heterogeneous reservoirs to inject ternary combination slug after profile control.
基金Supported by Postgraduate Scientific Research Foundation(A-2500-11-0079)Shanghai Engineering Research Center of Aquatic-Product Processing&Preservation Foundation(11DZ2280300)Aquaculture Genetics and Breeding Technology Center in Shanghai Ocean University(ZF1206)~~
文摘The research explored the extraction techniques of organic solvents of Antarctic kril oil and the effects of freezing temperature, extractant proportion, ex-traction time, drying temperature and ratio of material and liquid on extraction ratio of Antarctic kril oil. Based on single-factor experiments, optimal extraction conditions were concluded as per response surface methodology, as fol ows： freezing tempera-ture at -38.5 ℃, the ratio of material and liquid at 1 g：6.7 ml, and drying tempera-ture at 66.8 ℃, where the yield rate of crude oil reached 13.71%.
文摘Highly acidic crude oil is thermally soaked to investigate how the temperature and time involved affect the removal of organic acid in feedstock. Experimental results indicate that thermal treatment is an effective approach to decreasing acidity and the acid removal rate reaches 80%. Temperature is one of the main factors that determine the acid removal reaction. When the temperature ranges from 420oC to 440oC, the acid removal rate increases with the rise of the reaction temperature, but the increase slows down gradually. At the reaction temperature below 440oC, the long reaction time favors the acid removal. The cracking and polymerization of hydrocarbon molecules take place so that the properties of the crude oil change at the same time when the highly acidic crude is thermally treated.
基金Supported by Key Technologies of R&D Program of Shanxi Province(20120311019-1)Research Project Supported by Shanxi Scholarship Council of China(2012-110)+1 种基金Doctoral Research Fund of Shanxi Academy of Agricultural Sciences(YBSJJ1006)Key Technologies of R&D Program of Shanxi Academy of Agricultural Sciences(2012ygg16)~~
文摘[Objective] The research aimed to optimize laboratory artificial rearing methods for Plutella xylostella L. and to select out effective insecticides against this pest species. [Method] Brassica chinensis seedlings were cultivated in the laboratory at （25±1）℃, 60-75% RH, and a photoperiod of 14：10 （L：D） h. The green blow molding papers were used to collect eggs, and Brassica oleracea seedlings were cultivated to breed Plutella xylostella L. until the insects were ready for use. Mean-while, the susceptibility of 3rd instar larvae of Plutella xylostella L. to five types of insecticides was tested by leaf-dipping method. [Result] Plutella xylostella L. larvae were found well-grown and uniform in developmental stages with average pupa weight of 5.4 mg, pupa emergence percentage of 94.0 % and egg number of 135.1 per female. The LCso values of 3rd instar Plutella xylostella L. larvae against 200 g/L chlorantraniliprole SC, 20% flubendiamide WG, 150 g/L indoxacarb EC, 200 g/L tebufenozide SC and 1.8% abamectin EC, were 0.152, 0.223, 1.151, 93.340 and 0.128 mg/L, respectively. [Conclusion] This rearing method is easy to be implemented and of great practicality, suitable for mass propagation of P. xylostella L. Abamectin, chlorantraniliprole and flubendiamide showed high insecticidal activities, so these three insecticides can be used alternately for the field prevention and control of Plutella xylostella L.
文摘On July 8th, 2005, China＇s largest integrated oil refining and chemical joint-venture project was officially launched in Quanzhou, Fujian Province, indicating that another petrochemical base is growing up following Sinopec Qilu Petrochemical Company, Sinopec Beijing Yanhua Petrochemical Co. Ltd,
文摘E-commerce is known as the most advanced business mode, being the new point for global economic growth in 21 century. Comparing to the traditional purchase mode, E-commerce is available for reducing the purchasing cost and improving the working efficiency, thus lifting the whole benefit for the company through centralized purchasing.
文摘The trial of oil displacement driven by natural gas injection in China has been successfully accomplished recently for the first time in Zhongyuan Oilfield, Henan Province. This technology is ready for oilfield application in July.
