Several media report highlight on that the pharmaceutical companies require ultra-low temperatures -80<span style="white-space:nowrap;">°</span>C to transport and store its COVID-19 vaccines...Several media report highlight on that the pharmaceutical companies require ultra-low temperatures -80<span style="white-space:nowrap;">°</span>C to transport and store its COVID-19 vaccines. This research presents the thermodynamic analysis on cascade refrigeration system (CRS) with several refrigerant pairs which are R32/R170, R123/R170, R134a/R170, R404A/R170, R407c/R170, R410/R170, and the hydrocarbon (HC) refrigerant pair Propane/Ethane, namely R290/R170. Besides, the results of R22/R170 pair, which is not recommended to be used due to phase out of R22 as per Montréal Protocol, are included as base case to compare the novel hydrocarbon pairs in CRS and the old trend of refrigerant pairs. Thermodynamic properties of all these pairs were investigated and compared under different intermediate temperature used in CRS heat exchanger, which thermally connected both the Low and High temperature cycles (LTC) and (HTC). By applying the first law of thermodynamics, the coefficients of performance (COPs) and the specific power consumptions (SPC) in kW/TR are presented and compared. In addition, by applying the second law of thermodynamics the exergetic efficiencies were estimated. The results reveal the promising opportunity of using the HC pair (R290/R170). The minimum SPC in kW/TR is recorded for the pair R123/R170. One the other hand, the highest exegetic efficiency values are observed to be 40%, 38%, and 35% for the pairs R123/R170, R290/R170, and R134/R170, respectively. This research concludes that the HC pair (R290/R170) is highly recommended for CRS applications either to transport the COVID-19 or store it in cold storage rooms in hospitals and clinics. All precautionary measures should be carefully applied in design and operation of HC pair (R290/R170) due to its flammability hazard.展开更多
The rapid expansion of human resources has caused damage to our living environment. The concept of green economy with low power consumption and low pollution is becoming the focus of global attention. This article rev...The rapid expansion of human resources has caused damage to our living environment. The concept of green economy with low power consumption and low pollution is becoming the focus of global attention. This article reviews the development of green supply chain management （GSCM）, and briefly introduces the current methods of GSCM. In order to implement GSCM in the round, this paper recommends the life-cycle analysis, and proposed GSCM methods which the different types of companies should adopt.展开更多
Organic agriculture is one of successful models of low-carbon agriculture, and plays an important role in alleviating and adapting to climate change. However, the development of supply chain of organic agricultural pr...Organic agriculture is one of successful models of low-carbon agriculture, and plays an important role in alleviating and adapting to climate change. However, the development of supply chain of organic agricultural products lags behind, which seriously restricts development of organic agricultural product market. In this paper, major models and bottleneck of supply chain of organic agricultural products are analyzed, and finally countermeasures are put forward.展开更多
The optimal decision-making of the low-carbon supply chain incorporating fairness concerns, such as the effort of reducing carbon emissions, the whole sale price and retail price, is analyzed by taking the Nash bargai...The optimal decision-making of the low-carbon supply chain incorporating fairness concerns, such as the effort of reducing carbon emissions, the whole sale price and retail price, is analyzed by taking the Nash bargaining solution as the fairness reference point. The following conclusions are found. Firstly, the wholesale price is strongly influenced by the fairness concern of the manufacturer but weakly influenced by that of the retailer, although both statistically significantly. Secondly, both the manufacturer’s and retailer’s fairness concerns reduce carbon emissions dramatically to nearly the same extent. Thirdly, the effect of the manufacturer’s fairness concern on the retail price is so tiny that it can almost be ignored, while the retailer’s fairness concern changes the retail price remarkably.展开更多
Firstly, the construction background and basic connotations of CNOOC's Green Supply Chain was presented in this paper. Then, a detailed introduction to CNOOC's good practices for building green oil and gas fie...Firstly, the construction background and basic connotations of CNOOC's Green Supply Chain was presented in this paper. Then, a detailed introduction to CNOOC's good practices for building green oil and gas fields, green power plants, green refineries and green chemical plants was given with respect to the establishment of a green production construction and assessment system as well as green exploration, green manufacturing,green products, green sales, green recovery and other aspects. Finally, the effects of the Green Supply Chain established by CNOOC were summarized.展开更多
文摘Several media report highlight on that the pharmaceutical companies require ultra-low temperatures -80<span style="white-space:nowrap;">°</span>C to transport and store its COVID-19 vaccines. This research presents the thermodynamic analysis on cascade refrigeration system (CRS) with several refrigerant pairs which are R32/R170, R123/R170, R134a/R170, R404A/R170, R407c/R170, R410/R170, and the hydrocarbon (HC) refrigerant pair Propane/Ethane, namely R290/R170. Besides, the results of R22/R170 pair, which is not recommended to be used due to phase out of R22 as per Montréal Protocol, are included as base case to compare the novel hydrocarbon pairs in CRS and the old trend of refrigerant pairs. Thermodynamic properties of all these pairs were investigated and compared under different intermediate temperature used in CRS heat exchanger, which thermally connected both the Low and High temperature cycles (LTC) and (HTC). By applying the first law of thermodynamics, the coefficients of performance (COPs) and the specific power consumptions (SPC) in kW/TR are presented and compared. In addition, by applying the second law of thermodynamics the exergetic efficiencies were estimated. The results reveal the promising opportunity of using the HC pair (R290/R170). The minimum SPC in kW/TR is recorded for the pair R123/R170. One the other hand, the highest exegetic efficiency values are observed to be 40%, 38%, and 35% for the pairs R123/R170, R290/R170, and R134/R170, respectively. This research concludes that the HC pair (R290/R170) is highly recommended for CRS applications either to transport the COVID-19 or store it in cold storage rooms in hospitals and clinics. All precautionary measures should be carefully applied in design and operation of HC pair (R290/R170) due to its flammability hazard.
文摘The rapid expansion of human resources has caused damage to our living environment. The concept of green economy with low power consumption and low pollution is becoming the focus of global attention. This article reviews the development of green supply chain management （GSCM）, and briefly introduces the current methods of GSCM. In order to implement GSCM in the round, this paper recommends the life-cycle analysis, and proposed GSCM methods which the different types of companies should adopt.
基金Supported by Beijing Philosophy and Social Science Planning Project(No.:11JGB035)Henan Province Soft Science Project of 2011(112400430012)
文摘Organic agriculture is one of successful models of low-carbon agriculture, and plays an important role in alleviating and adapting to climate change. However, the development of supply chain of organic agricultural products lags behind, which seriously restricts development of organic agricultural product market. In this paper, major models and bottleneck of supply chain of organic agricultural products are analyzed, and finally countermeasures are put forward.
基金Supported by National Social Science Foundation of China(16CGL017)
文摘The optimal decision-making of the low-carbon supply chain incorporating fairness concerns, such as the effort of reducing carbon emissions, the whole sale price and retail price, is analyzed by taking the Nash bargaining solution as the fairness reference point. The following conclusions are found. Firstly, the wholesale price is strongly influenced by the fairness concern of the manufacturer but weakly influenced by that of the retailer, although both statistically significantly. Secondly, both the manufacturer’s and retailer’s fairness concerns reduce carbon emissions dramatically to nearly the same extent. Thirdly, the effect of the manufacturer’s fairness concern on the retail price is so tiny that it can almost be ignored, while the retailer’s fairness concern changes the retail price remarkably.
文摘Firstly, the construction background and basic connotations of CNOOC's Green Supply Chain was presented in this paper. Then, a detailed introduction to CNOOC's good practices for building green oil and gas fields, green power plants, green refineries and green chemical plants was given with respect to the establishment of a green production construction and assessment system as well as green exploration, green manufacturing,green products, green sales, green recovery and other aspects. Finally, the effects of the Green Supply Chain established by CNOOC were summarized.
