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The Supply Chain Contract Design under Cap-and-Trade Mechanism with Free Riding

Fu-qiang Wang,Jun Liu

《工程管理前沿(英文)》 2015年 第2卷 第3期   页码 277-286 doi: 10.15302/J-FEM-2015049

摘要: This paper studies the influence of free riding on enterprise product pricing and carbon emissions reduction investment, as well as the contract design to achieve supply chain coordination under the carbon trading mechanism. First, we discuss the situation where carbon emissions reduction investment affects the product price and income. It demonstrates that the optimal investment of the upstream manufacturer increases with the degree of the free riding of the downstream manufacturer. The upstream manufacturer can improve their carbon reduction investment and the whole supply chain achieves Pareto improvement when the investment cost sharing contract is introduced. Nevertheless, under the cost-sharing contract the optimal investment of the decentralized supply chain is still lower than that of the centralized supply chain, and only in some particular cases can the two types of supply chain achieve equal total profits. Then, we preliminarily explore the situation where the product price and income is influenced by carbon emissions reduction investment. The consequences indicate that the optimal investment of the upstream manufacturers in this situation is less than the former one’s, and the transfer payment mechanism is able to improve the level of the supply chain overall carbon emissions-reduction. Moreover, compared to the former situation, the effects of free riding of the downstream manufacturer are even more serious. The conclusions can provide some intellectual support for manufacturing enterprises to make reasonable emissions reduction strategies and coordinate the supply chain existing in free riding.

关键词: carbon emissions reduction     free riding     supply chain contract design     cap-and-trade    

Pathways toward a pollution-free planet and challenges

《环境科学与工程前沿(英文)》 2024年 第18卷 第6期 doi: 10.1007/s11783-024-1827-0

摘要:

● Zero pollution does not mean no discharge of pollutants.

关键词: Wastewater treatment     Resources     Recovery     Greenhouse gases     Energy     Pollution-free    

Cell-free systems in the new age of synthetic biology

Fernando Villarreal,Cheemeng Tan

《化学科学与工程前沿(英文)》 2017年 第11卷 第1期   页码 58-65 doi: 10.1007/s11705-017-1610-x

摘要: The advent of synthetic biology has ushered in new applications of cell-free transcription-translation systems. These cell-free systems are reconstituted using cellular proteins, and are amenable to modular control of their composition. Here, we discuss the historical advancement of cell-free systems, as well as their new applications in the rapid design of synthetic genetic circuits and components, directed evolution of biomolecules, diagnosis of infectious diseases, and synthesis of vaccines. Finally, we present our vision on the future direction of cell-free synthetic biology.

关键词: cell-free system     application    

Decontamination of Cr(VI) facilitated formation of persistent free radicals on rice husk derived biochar

Kaikai Zhang, Peng Sun, Yanrong Zhang

《环境科学与工程前沿(英文)》 2019年 第13卷 第2期 doi: 10.1007/s11783-019-1106-7

摘要:

PFRs were produced on biochar during Cr(VI) decontamination.

PFRs formation on biochar was owing to the oxidization of phenolic-OH by Cr(VI).

Appearance of excessive oxidant led to the consumption of PFRs on biochar.

Biochar charred at high temperature possessed great performance to Cr(VI) removal.

关键词: Biochar     Persistent free radicals     Phenolic hydroxyl groups     Cr(VI) reduction    

Recent advances in cycloaddition of CO with epoxides: halogen-free catalysis and mechanistic insights

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 1879-1894 doi: 10.1007/s11705-023-2354-4

摘要: The atom-economical cycloaddition of CO2 with epoxides to synthesize cyclic carbonates is a promising route for valuable utilization of CO2. Halogenide such as alkali metal halides and quaternary ammonium salt have been developed as the efficient catalysts. However, the spilled halogen causes equipment corrosion and affects the product purity. To address these concerns, the halogen-free cycloaddition of CO2 with epoxides has always been desired. In this review, we systematically discussed the halogen-free catalysis for cycloaddition of CO2 with epoxides from the mechanistic insights, aiming to promote the development of efficient halogen-free catalysts. Two types of catalysts, i.e., alternatives of halogen nucleophiles for epoxide activation, and bifunctional catalysts with Lewis acid-base sites for synergistic activation of CO2 and epoxides are summarized and emphasized. Specially, metal oxides as the potential halogen-free catalysts are highlighted due to their flexible acid-base sites for synergistic activation of CO2 and epoxides, facile preparation, and low cost.

关键词: carbon dioxide     halogen-free catalysis     cyclic carbonate     mechanistic insight    

Thermoresponsive block copolymer supported Pt nanocatalysts for base-free aerobic oxidation of 5-hydroxymethyl

《化学科学与工程前沿(英文)》 2021年 第15卷 第6期   页码 1514-1523 doi: 10.1007/s11705-021-2092-4

摘要: A base-free catalytic system for the aerobic oxidation of 5-hydroxymethyl-2-furfural was exploited by using Pt nanoparticles immobilized onto a thermoresponsive poly(acrylamide-co-acrylonitrile)-b-poly(N-vinylimidazole) block copolymer, with an upper critical solution temperature of about 45 °C. The Pt nanocatalysts were well-dispersed and highly active for the base-free oxidation of 5-hydroxymethyl-2-furfural by molecular oxygen in water, affording high yields of 2,5-furandicarboxylic acid (up to>99.9%). The imidazole groups in the block copolymer were conducive to the improvement of catalytic performance. Moreover, the catalysts could be easily separated and recovered based on their thermosensitivity by cooling the reaction system below the upper critical solution temperature. Good stability and reusability were observed over these copolymer-immobilized catalysts with no obvious decrease in catalytic activity in the five consecutive cycles.

关键词: aerobic oxidation     base-free     5-hydroxymethyl-2-furfural     Pt nanoparticle     thermoresponsive block copolymer    

Hollow carbon spheres and their noble metal-free hybrids in catalysis

《化学科学与工程前沿(英文)》 2021年 第15卷 第6期   页码 1380-1407 doi: 10.1007/s11705-021-2097-z

摘要: Hollow carbon spheres have garnered great interest owing to their high surface area, large surface-to-volume ratio and reduced transmission lengths. Herein, we overview hollow carbon sphere-based materials and their noble metal-free hybrids in catalysis. Firstly, we summarize the key fabrication techniques for various kinds of hollow carbon spheres, with a particular emphasis on controlling pore structure and surface morphology, and then heterogeneous doping as well as their metal-free/containing hybrids are presented; next, possible applications for non-noble metal/hollow carbon sphere hybrids in the area of energy-related catalysis, including oxygen reduction reaction, hydrogen evolution reaction, oxygen evolution reaction, water splitting, rechargeable Zn-air batteries and pollutant degradation are discussed; finally, we introduce the various challenges and opportunities offered by hollow carbon spheres from the perspective of synthesis and catalysis.

关键词: hollow carbon spheres     functionalization     noble metal-free     catalysis    

Together towards a pollution-free planet

《环境科学与工程前沿(英文)》 2024年 第18卷 第6期 doi: 10.1007/s11783-024-1826-1

Design and modeling of a free-piston engine generator

《能源前沿(英文)》 2023年 第17卷 第6期   页码 811-821 doi: 10.1007/s11708-022-0848-2

摘要: Free-piston engine generators (FPEGs) can be applied as decarbonized range extenders for electric vehicles because of their high thermal efficiency, low friction loss, and ultimate fuel flexibility. In this paper, a parameter-decoupling approach is proposed to model the design of an FPEG. The parameter-decoupling approach first divides the FPEG into three parts: a two-stroke engine, an integrated scavenging pump, and a linear permanent magnet synchronous machine (LPMSM). Then, each of these is designed according to predefined specifications and performance targets. Using this decoupling approach, a numerical model of the FPEG, including the three aforementioned parts, was developed. Empirical equations were adopted to design the engine and scavenging pump, while special considerations were applied for the LPMSM. A finite element model with a multi-objective genetic algorithm was adopted for its design. The finite element model results were fed back to the numerical model to update the LPMSM with increased fidelity. The designed FPEG produced 10.2 kW of electric power with an overall system efficiency of 38.5% in a stable manner. The model provides a solid foundation for the manufacturing of related FPEG prototypes.

关键词: free-piston engine generator     linear permanent magnet synchronous machine     system design     numerical model     finite element method    

Influence of the filler materials on flux-free brazing of pure aluminium (1050)

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA,

《机械工程前沿(英文)》 2010年 第5卷 第1期   页码 47-51 doi: 10.1007/s11465-009-0079-9

摘要: In the present study, samples of pure aluminium (1050) were deposited by cold spraying with filler materials such as Al12Si, Al7Si, Al12Si-4%Cu, and the Al-Si-based filler material A, which was especially developed for flux-free brazing by the Surface Engineering Institute. Besides, pure Si powder was also sprayed. The coated samples were heat-treated under different conditions and were brazed under an argon atmosphere without fluxes or with the flux Nokolok by an induction heating system. The shear strength of the brazed joints was determined. The results show that the filler materials could be well deposited by cold spraying. A thin layer of brittle Si could also form due to the strong deformation of the substrate surface. The heat treatments showed that a very good metallurgical bond between the filler materials and the substrate could be realized by the deposition by cold spraying. The Al7Si deposited samples could not be brazed without fluxes under the given conditions. The samples deposited with other filler materials could be brazed without fluxes. The in-situ diffusion process made it possible to braze the Si-deposited samples at 580°C. The joints of the samples deposited with the filler material showed the highest shear strength of 41 MPa, whereas the values of the Al12Si and Si deposited samples were less than 20 MPa. The employment of the flux Nikolok significantly increased the shear strength of the Al12Si deposited samples to more than 53 MPa.

关键词: aluminium     flux-free brazing     cold spraying     shear strength    

Highly selective detection of copper(II) by a “ligand-free” conjugated copolymer in nucleophilic solvents

Weixing Deng, Pengfei Sun, Quli Fan, Lei Zhang, Tsuyoshi Minami

《化学科学与工程前沿(英文)》 2020年 第14卷 第1期   页码 105-111 doi: 10.1007/s11705-019-1791-6

摘要: The synthesis of -cyclohexyl carbamate-attached fluorene- -phenylene copolymer (PFPNCC) and the use of PFPNCC as a “ligand-free” fluorescent chemosensor for Cu(II) are described. Addition of Cu(II) can efficiently quench the fluorescence of PFPNCC in nucleophilic solvents such as DMF and DMSO, but not in low nucleophilic solvents such as 1,4-dioxane and THF. Ultraviolet-visible spectra of the mixture of the conjugated polymer and Cu(II) indicate the presence of a reduced Cu(I) ion in the solution. Furthermore, fluorescence recovery of PFPNCC observed at low temperature suggests that the quenching and reducing mechanism is most probably due to a photo-induced electron transfer from excited PFPNCC to Cu(II). Our findings provide a novel strategy for highly selective conjugated polymer-based chemosensors for various target analytes, albeit “ligand-free”.

关键词: ligand-free     fluorescent chemosensor     copper     photo-induced electron transfer    

New perspectives in free nitrous acid (FNA) uses for sustainable wastewater management

《环境科学与工程前沿(英文)》 2024年 第18卷 第2期 doi: 10.1007/s11783-024-1786-5

摘要:

● The historical development of free nitrous acid (FNA) technologies is reviewed.

关键词: Free nitrous acid     Acid-tolerant ammonia oxidizer     In situ generation     Wastewater management    

Solvent-free mechanochemical mild oxidation method to enhance adsorption properties of chitosan

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1416-4

摘要:

• Solvent-free chitosan oxidation is obtained by rapid mechanochemical reaction.

关键词: Chitosan     High energy ball milling     Mechanochemistry     Oxidation    

Design approach for single piston hydraulic free piston diesel engines

Wei WU, Shihua YUAN, Jibin HU, Chongbo JING,

《机械工程前沿(英文)》 2009年 第4卷 第4期   页码 371-378 doi: 10.1007/s11465-009-0069-y

摘要: The operating characteristics of a single piston hydraulic free piston diesel engine differ significantly from conventional diesel engines and this provides a theoretical basis for controlling and optimizing the design of the engine. The design of the proposed engine intended as a power supply for a hydraulic propulsion vehicle is presented. An engine performance forecast model was generated in AMESim. The performance of the prototype engine is predicted and the predictive results are verified with experiments. The particular features of the engine are discussed. The dynamic characteristics of the prototype engine are analyzed and the results indicate the rationality and feasibility of the engine design parameters. The features of the controllable working frequency and the intermittence output flows are provided. The flow capacity characteristics of the hydraulic valves on the prototype engine are offered. The methods for starting and the operation after misfire are presented.

关键词: free piston engine (FPE)     diesel engine     hydraulic equipment     simulation     experiment    

“ALL FREE” — a novel design concept of applying partial oxidation process to vehicle

Ling LIN, Wenshuang LIN, Qingbiao LI, Yao ZHOU,

《化学科学与工程前沿(英文)》 2010年 第4卷 第2期   页码 207-212 doi: 10.1007/s11705-009-0240-3

摘要: With the rapid expansion of the global motor vehicle population, the transportation sector has taken up a growing proportion among all the carbon dioxide emission-related sectors. To contribute to solutions of the carbon dioxide-oriented problem in transportation, this paper proposes the “ALL FREE” concept that applies partial oxidation process instead of the conventional complete oxidation to vehicle engines. In such an engine, the fuels are partially oxidized into corresponding chemical products, which, as a result, enable the process to be theoretically free of CO, while the heat output of the partial oxidation could drive the vehicle. On the other hand, the resulting products are of great value, which could decrease or even counteract the cost of fuels in transportation. In this paper, the thermodynamic and kinetic data (e.g., the heat output and heat release rate) of five selected partial oxidation reactions were calculated at length to demonstrate and exemplify the theoretical feasibility of the “ALL FREE” concept. It turned out that the partial oxidation of -butane to maleic anhydride has the most potential to meet the basic requirements of this concept. To sum up, this design concept is of significant application potential for the reduction of CO emissions in the transportation industry, although there remain many technical challenges.

关键词: oxidation process     CO     complete oxidation     ALL FREE     -butane    

标题 作者 时间 类型 操作

The Supply Chain Contract Design under Cap-and-Trade Mechanism with Free Riding

Fu-qiang Wang,Jun Liu

期刊论文

Pathways toward a pollution-free planet and challenges

期刊论文

Cell-free systems in the new age of synthetic biology

Fernando Villarreal,Cheemeng Tan

期刊论文

Decontamination of Cr(VI) facilitated formation of persistent free radicals on rice husk derived biochar

Kaikai Zhang, Peng Sun, Yanrong Zhang

期刊论文

Recent advances in cycloaddition of CO with epoxides: halogen-free catalysis and mechanistic insights

期刊论文

Thermoresponsive block copolymer supported Pt nanocatalysts for base-free aerobic oxidation of 5-hydroxymethyl

期刊论文

Hollow carbon spheres and their noble metal-free hybrids in catalysis

期刊论文

Together towards a pollution-free planet

期刊论文

Design and modeling of a free-piston engine generator

期刊论文

Influence of the filler materials on flux-free brazing of pure aluminium (1050)

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA,

期刊论文

Highly selective detection of copper(II) by a “ligand-free” conjugated copolymer in nucleophilic solvents

Weixing Deng, Pengfei Sun, Quli Fan, Lei Zhang, Tsuyoshi Minami

期刊论文

New perspectives in free nitrous acid (FNA) uses for sustainable wastewater management

期刊论文

Solvent-free mechanochemical mild oxidation method to enhance adsorption properties of chitosan

期刊论文

Design approach for single piston hydraulic free piston diesel engines

Wei WU, Shihua YUAN, Jibin HU, Chongbo JING,

期刊论文

“ALL FREE” — a novel design concept of applying partial oxidation process to vehicle

Ling LIN, Wenshuang LIN, Qingbiao LI, Yao ZHOU,

期刊论文