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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    

Engineering Management to Serve All Human Beings

Yong-fu Sun

《工程管理前沿(英文)》 2014年 第1卷 第3期   页码 231-231 doi: 10.15302/J-FEM-2014032

Enhanced charge extraction for all-inorganic perovskite solar cells by graphene oxide quantum dots modified

《化学科学与工程前沿(英文)》 2023年 第17卷 第5期   页码 516-524 doi: 10.1007/s11705-022-2238-z

摘要: All-inorganic cesium lead bromide (CsPbBr3) perovskite solar cells have been attracting growing interest due to superior performance stability and low cost. However, low light absorbance and large charge recombination at TiO2/CsPbBr3 interface or within CsPbBr3 film still prevent further performance improvement. Herein, we report devices with high power conversion efficiency (9.16%) by introducing graphene oxide quantum dots (GOQDs) between TiO2 and perovskite layers. The recombination of interfacial radiation can be effectively restrained due to enhanced charge transfer capability. GOQDs with C-rich active sites can involve in crystallization and fill within the CsPbBr3 perovskite film as functional semiconductor additives. This work provides a promising strategy to optimize the crystallization process and boost charge extraction at the surface/interface optoelectronic properties of perovskites for high efficient and low-cost solar cells.

关键词: all inorganic     perovskite solar cells     graphene oxide quantum dots     high performance     stability    

Renin--angiotensin system inhibitor is associated with the reduced risk of all-cause mortality in COVID

《医学前沿(英文)》 2022年 第16卷 第1期   页码 102-110 doi: 10.1007/s11684-021-0850-9

摘要: Consecutively hospitalized patients with confirmed coronavirus disease 2019 (COVID-19) in Wuhan, China were retrospectively enrolled from January 2020 to March 2020 to investigate the association between the use of renin–angiotensin system inhibitor (RAS-I) and the outcome of this disease. Associations between the use of RAS-I (angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB)), ACEI, and ARB and in-hospital mortality were analyzed using multivariate Cox proportional hazards regression models in overall and subgroup of hypertension status. A total of 2771 patients with COVID-19 were included, with moderate and severe cases accounting for 45.0% and 36.5%, respectively. A total of 195 (7.0%) patients died. RAS-I (hazard ratio (HR)=0.499, 95% confidence interval (CI) 0.325–0.767) and ARB (HR=0.410, 95% CI 0.240–0.700) use was associated with a reduced risk of all-cause mortality among patients with COVID-19. For patients with hypertension, RAS-I and ARB applications were also associated with a reduced risk of mortality with HR of 0.352 (95% CI 0.162–0.764) and 0.279 (95% CI 0.115–0.677), respectively. RAS-I exhibited protective effects on the survival outcome of COVID-19. ARB use was associated with a reduced risk of all-cause mortality among patients with COVID-19.

关键词: COVID-19     RAS inhibitor     hypertension     all-cause mortality    

Primary health care for all by 2020: The systematic reform of the medical and health system in China

《医学前沿(英文)》 2010年 第4卷 第1期   页码 3-7 doi: 10.1007/s11684-010-0024-7

用于超快电子器件的全通型波导 Article

Desong Wang, Ke Wu

《工程(英文)》 2023年 第30卷 第11期   页码 49-54 doi: 10.1016/j.eng.2023.04.005

摘要:

Ultrashort pulse transmission has been recognized as a primary problem that fundamentally hinders the development of ultrafast electronics beyond the current nanosecond timescale. This requires a transmission line or waveguide that exhibits an all-pass frequency behavior for the transmitted ultrashort pulse signals. However, this type of waveguiding structure has not yet been practically developed; groundbreaking innovations and advances in signal transmission technology are urgently required to address this scenario. Herein, we present a synthesized all-pass waveguide that demonstrates record guided-wave controlling capabilities, including eigenmode reshaping, polarization rotation, loss reduction, and dispersion improvement. We experimentally developed two waveguides for use in ultrabroad frequency ranges (direct current (DC)-to-millimeter-wave and DC-to-terahertz). Our results suggest that the waveguides can efficiently transmit picosecond electrical pulses while maintaining signal integrity. This waveguide technology is an important breakthrough in the evolution of ultrafast electronics, providing a path towards frequency-engineered ultrashort pulses for low-loss and low-dispersion transmissions.

关键词: All-pass waveguide     Ultrashort pulse     Picosecond transmission     Ultrafast electronics     Terahertz technology     Mode-selective transmission line    

统一集论与人工智能

张江,林华,贺仲雄

《中国工程科学》 2002年 第4卷 第3期   页码 40-47

摘要:

通过综合经典集合、模糊集合、可拓集合、Vague集合、粗糙集合、集对分析、FHW(模糊灰色物元空间)、FEEC(模糊可拓经济控制)等多种理论,提出了统一集概念,并详细讨论统一集的各种运算以及相关性质。从分析集合理论和人类思维形式之间的关系人手,把统一集理论初步应用到模式识别、聚类分析、逻辑推理、机器学习、智能决策等多种人工智能领域,指出了集合论及其运算系统与逻辑推理系统的等价关系。统一集能对现有的理论进行总结、统一,还为开辟崭新的集合论、逻辑推理方法提供很好的理论基础。

关键词: 统一集     人工智能     集合     运算     逻辑推理    

Thanks to all medical workers fighting against COVID-19

Xiao-ping Chen

《医学前沿(英文)》 2020年 第14卷 第2期   页码 249-250 doi: 10.1007/s11684-020-0789-2

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    

Yellow fever and Hajj: with all eyes on Zika, a familiar flavivirus remains a threat

null

《医学前沿(英文)》 2016年 第10卷 第4期   页码 527-530 doi: 10.1007/s11684-016-0487-2

摘要:

Hajj is among the world’s largest mass gatherings, drawing between 2 and 3.5 million Muslims from 183 nations annually to perform pilgrimage in Mecca, Saudi Arabia. Infectious disease outbreaks can be imported both into the Hajj population and exported internationally by returning pilgrims. The domestic Saudi population can also be at risk of outbreaks traveling amid this mass migration. With yellow fever reported for the first time in China following the infection of expatriate Chinese workers in Angola and a full blown outbreak underway in wider West Africa, the prospect of yellow fever outbreaks in Asia threatens to impact Saudi Arabia, both during and beyond the Hajj season. With global focus trained on Zika, the rising threat of yellow fever cannot be overlooked. Strategies to mitigate risk to Saudi Arabia and the global population are thereby suggested.

关键词: yellow fever     mass gathering     Saudi Arabia     Hajj     Zika virus    

全气候新能源汽车关键技术及展望

王文伟,孙逢春

《中国工程科学》 2019年 第21卷 第3期   页码 47-55 doi: 10.15302/J-SSCAE-2019.03.020

摘要:

全气候新能源汽车是指能够适应包括高温、高湿和极寒等各种气候环境的新能源汽车,相对于目前高温高湿环境下较为成熟的隔热散热与防护技术,新能源汽车在超过–30 ℃的极寒环境下存在无法启动、续驶里程锐减、充电困难等问题,是国际社会公认的制约新能源汽车全气候应用的难题。本文分析研究了动力电池自加热技术、高效冷暖一体化热泵空调技术、新型整车隔热保温技术等全气候新能源汽车技术体系,并进行了整车集成开发及极寒环境试验,最后分析了全气候新能源汽车的技术发展趋势。本文所述的研究成果将通过在2022 年北京冬季奥林匹克运动会上率先进行示范应用,从而推动我国乃至国际新能源汽车的全气候应用。

关键词: 全气候新能源汽车     电池自加热     热泵空调     隔热保温    

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    

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    

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    

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    

标题 作者 时间 类型 操作

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

Engineering Management to Serve All Human Beings

Yong-fu Sun

期刊论文

Enhanced charge extraction for all-inorganic perovskite solar cells by graphene oxide quantum dots modified

期刊论文

Renin--angiotensin system inhibitor is associated with the reduced risk of all-cause mortality in COVID

期刊论文

Primary health care for all by 2020: The systematic reform of the medical and health system in China

期刊论文

用于超快电子器件的全通型波导

Desong Wang, Ke Wu

期刊论文

统一集论与人工智能

张江,林华,贺仲雄

期刊论文

Thanks to all medical workers fighting against COVID-19

Xiao-ping Chen

期刊论文

Cell-free systems in the new age of synthetic biology

Fernando Villarreal,Cheemeng Tan

期刊论文

Yellow fever and Hajj: with all eyes on Zika, a familiar flavivirus remains a threat

null

期刊论文

全气候新能源汽车关键技术及展望

王文伟,孙逢春

期刊论文

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

期刊论文

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

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

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

期刊论文