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Study on reformulation of fluid catalytic cracking gasoline and increasing production of light olefins

YAN Pingxiang, MENG Xianghai, GAO Jinsen, XU Chunming, SUI Zhiyu

《化学科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 74-79 doi: 10.1007/s11705-008-0016-1

摘要： The effects of reaction temperature, mass ratio of catalyst to oil, space velocity, and mass ratio of water to oil on the product distribution, the yields of light olefins (light olefins including ethylene, propylene and butylene) and the composition of the fluid catalytic cracking (FCC) gasoline upgraded over the self-made catalyst GL in a confined fluidized bed reactor were investigated. The experimental results showed that FCC gasoline was obviously reformulated under appropriate reaction conditions. The olefins (olefins with C atom number above 4) content of FCC gasoline was markedly reduced, and the aromatics content and octane number were increased. The upgraded gasoline met the new standard of gasoline, and meanwhile, higher yields of light olefins were obtained. Furthermore, higher reaction temperature, higher mass ratio of catalyst to oil, higher mass ratio of water to oil, and lower space velocity were found to be beneficial to FCC gasoline reformulation and light olefins production.
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A 14-year measurement of toxic elements in atmospheric particulates in Hong Kong from 1995 to 2008

Wei NIE,Tao WANG,Aijun DING,Xuehua ZHOU,Wenxing WANG

《环境科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 553-560 doi: 10.1007/s11783-013-0523-2

摘要： Toxic elements in the atmosphere can enter and accumulate in the human body, seriously impacting human health. In this study, we analyzed a 14-year (1995–2008) measurement of three toxic elements (As, Cd and Cr) in PM in Hong Kong, China. The pollution of these toxic elements in Hong Kong was not serious. The trend analysis showed that As and Cr in PM increased at a statistically significant level ( <0.05) during the 14-year period, while the Cd in PM did not change significantly. Typical seasonal variations were observed for all three toxic elements, largely in relation to the Asian monsoon. Hourly 10-day backward trajectories were computed and categorised into four groups. The continental air masses showed much higher concentrations of the three toxic elements than the marine air masses. The abundances of As and Cd in the PM were much higher in the continental air masses than those in the marine air masses, while the abundances of Cr showed an opposite pattern. The trends of the three toxic elements in East China’s air mass were consistent with those in the overall data set of Hong Kong. Examination of the toxic element data recorded at urban sites and a roadside site also indicated a large contribution of external air masses to particulate As and Cd in Hong Kong. These results suggest that the long-range transport from the mainland of China is the dominant contributor to particulate As and Cd, while both local and long-distance sources determine the particulate Cr in Hong Kong.

关键词： toxic elements     increasing trends     seasonal variations     air masses     long-distance sources    

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Influence of increasing numbers of RE-inverters on the power quality in the distribution grids: A PQ

Przemyslaw JANIK, Grzegorz KOSOBUDZKI, Harald SCHWARZ

《能源前沿（英文）》 2017年 第11卷 第2期   页码 155-167 doi: 10.1007/s11708-017-0469-3

摘要： This paper presents the selected power quality (PQ) indicia of a wind generator and a photovoltaic installation considered to be the representative of medium voltage and low voltage distribution grids. The analysis of measured values suggests that the decrease in PQ is a case of specific combination of distributed generation, grid parameters and load behaviour. Modern generators have a limited impact on PQ. On the other hand, fluctuations in power generation are regarded as an emerging PQ indicator. The growing number of distributed renewable installations causes stochastic, variable, and hardly predictable power flows in the distribution grid. The nature of fluctuations in wind and solar generation is different. In both cases, new indexes for the quantification of fluctuations are needed and are yet not standardised. Proper assessment of these fluctuations enables definition of useful fluctuation limits and rules for optimal storage system integration.

关键词： power quality     harmonics     sags     photovoltaic(PV) system     doubly feed induction generator (DFIG)     inverters    

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Breeding strategies for increasing yield potential in super hybrid rice

Shihua CHENG,Xiaodeng ZHAN,Liyong CAO

《农业科学与工程前沿（英文）》 2015年 第2卷 第4期   页码 277-282 doi: 10.15302/J-FASE-2015081

摘要： Super hybrid rice breeding is a new breeding method combining semi-dwarf breeding and heterosis breeding using germplasm and gene-environment interactions. This paper reviews the breeding strategies of super hybrid rice breeding in China, focusing on the utilization of heterosis of indica and japonica subspecies, construction of ideal plant architecture and pyramiding of disease resistant genes in restorer lines. To develop super hybrid rice, considerable effort should be made to explore genes related with high yield, good quality, resistance to pests and diseases, tolerance to stresses. Molecular breeding methods in combination with crossing techniques should be adopted in super hybrid rice breeding.

关键词： super hybrid rice     breeding strategies     yield potential    

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Catalysis of semihydrogenation of acetylene to ethylene: current trends, challenges, and outlook

《化学科学与工程前沿（英文）》 2022年 第16卷 第7期   页码 1031-1059 doi: 10.1007/s11705-021-2113-3

摘要： Ethylene is an important feedstock for various industrial processes, particularly in the polymer industry. Unfortunately, during naphtha cracking to produce ethylene, there are instances of acetylene presence in the product stream, which poisons the Ziegler–Natta polymerization catalysts. Thus, appropriate process modification, optimization, and in particular, catalyst design are essential to ensure the production of highly pure ethylene that is suitable as a feedstock in polymerization reactions. Accordingly, carefully selected process parameters and the application of various catalyst systems have been optimized for this purpose. This review provides a holistic view of the recent reports on the selective hydrogenation of acetylene. Previously published reviews were limited to Pd catalysts. However, effective new metal and non-metal catalysts have been explored for selective acetylene hydrogenation. Updates on this recent progress and more comprehensive computational studies that are now available for the reaction are described herein. In addition to the favored Pd catalysts, other catalyst systems including mono, bimetallic, trimetallic, and ionic catalysts are presented. The specific role(s) that each process parameter plays to achieve high acetylene conversion and ethylene selectivity is discussed. Attempts have been made to elucidate the possible catalyst deactivation mechanisms involved in the reaction. Extensive reports suggest that acetylene adsorption occurs through an active single-site mechanism rather than via dual active sites. An increase in the reaction temperature affords high acetylene conversion and ethylene selectivity to obtain reactant streams free of ethylene. Conflicting findings to this trend have reported the presence of ethylene in the feed stream. This review will serve as a useful resource of condensed information for researchers in the field of acetylene-selective hydrogenation.

关键词： selectivity     hydrogenation     acetylene     ethylene     palladium    

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Mapping the trends and prospects of battery cathode materials based on patent landscape

《能源前沿（英文）》   页码 822-832 doi: 10.1007/s11708-023-0900-x

摘要： Advancing portable electronics and electric vehicles is heavily dependent on the cutting-edge lithium-ion (Li-ion) battery technology, which is closely linked to the properties of cathode materials. Identifying trends and prospects of cathode materials based on patent analysis is considered a kernel to optimize and refine battery related markets. In this paper, a patent analysis is performed on 6 popular cathode materials by comprehensively considering performance comparison, development trend, annual installed capacity, technology life cycle, and distribution among regions and patent assignees. In the technology life cycle, the cathode materials majorly used in electric vehicle have entered maturity stage, while the lithium cobalt oxide (LCO) cathode that is widely used in portable electronics is still in the growth stage. In global patent distributions, China holds more than 50% of total patents. In the top 10 patent assignees of 6 cathode materials, 2 institutes are from China with the rest being Japan (6) and Republic of Korea (2), indicating that the technology of cathode materials in China is relatively scattered while cathode research is highly concentrated in Japan and Republic of Korea. Moreover, the patent distribution has to consider practical issues as well as the impacts of core patents. For example, the high cost discourages the intention of applying international patents. This paper is expected to stimulate battery research, understand technical layout of various countries, and probably forecast innovative technology breakthroughs.

关键词： patent analysis     cathode     batteries     technology life cycle    

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Trends of environmental accidents and impact factors in China

Pengli XUE, Weihua ZENG

《环境科学与工程前沿（英文）》 2011年 第5卷 第2期   页码 266-276 doi: 10.1007/s11783-010-0267-1

摘要： An overview of the spatial and temporal variations of the environmental accidents in China in recent years was presented in this paper using available data. The results showed that the frequency of pollution accidents was significantly decreased, from 3462 in 1990 to 462 in 2007. The water and air pollution accidents were found to be the dominant types, accounting for more than 80% of the total accidents. Considering the classification of environmental accidents at 4 scales, the general environmental accident, i.e., the least serious type, was the most frequent event, taking up 58.98% of the total pollution accidents. In addition, the distribution of environmental accidents was generally in accordance with the industrial layout in the country during the past decade. It is very important to note that the extraordinarily severe environmental accidents showed an increasing trend in underdeveloped regions, which was caused by the transfer and the development of heavy polluted industry in these areas. As to the losses of environmental accidents, the casualties presented an obvious reduction tendency, while the direct economic loss per accident tended to climb up. Furthermore, some key factors that affect the spatial and temporal tendencies of environmental accidents in China were discussed and some suggestions were put forward, hoping to shed light on environmental risk management and emergency plans making associated with environmental accidents in China.

关键词： environmental accidents     spatial and temporal trends     environmental risk    

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Study of mechanism of activating flux increasing weld penetration of AC A-TIG welding for aluminum alloy

HUANG Yong, FAN Ding, FAN Qinghua

《机械工程前沿（英文）》 2007年 第2卷 第4期   页码 442-447 doi: 10.1007/s11465-007-0076-9

摘要： When multi-component flux AF305 is used as surface activating flux for an aluminum alloy, the weld pene tration of activating flux-tungsten inert-gas (A-TIG) welding is over two times more than that of conventional TIG welding. Using A-TIG welding with the modes of alternating current (AC), direct current electrode negative (DCEN) and direct current electrode positive (DCEP), respectively, the flux differently affects weld penetration when the polarity is different. After studied the effect of compelled arc con striction on weld penetration of AC welding, it is believed that the constriction of the whole arc root is not the main mechanism that flux AF305 dramatically improves weld penetration. The penetration has a relationship with the separate distribution of slag on the weld surface. Then, an observation of scanning electron microscopy (SEM) and an electronic data systems (EDS) analysis of slag were performed respectively. The separate distribution of slag on the weld pool during welding and the great constriction of arc spots were confirmed by TIG welding with helium shielding gas. The relationship between slag distribution and weld penetration was studied by adding aluminum powder into flux AF305 to change the distribution of slag. During welding, the separate distribution of slag on the weld pool results in the great constriction of arc spots, an increase in arc spot force, and an increase in Lorentz force within the arc and weld pool. Finally, the weld penetration is increased.

关键词： A-TIG welding     surface     DCEN     electrode negative     increase    

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Emerging trends in self-healable nanomaterials for triboelectric nanogenerators: A comprehensive review

《能源前沿（英文）》   页码 727-750 doi: 10.1007/s11708-023-0896-2

摘要： A thorough analysis of triboelectric nanogenerators (TENGs) that make use of self-healable nanomaterials is presented in this review. These TENGs have shown promise as independent energy sources that do not require an external power source to function. TENGs are developing into a viable choice for powering numerous applications as low-power electronics technology advances. Despite having less power than conventional energy sources, TENGs do not directly compete with these. TENGs, on the other hand, provide unique opportunities for future self-powered systems and might encourage advancements in energy and sensor technologies. Examining the many approaches used to improve nanogenerators by employing materials with shape memory and self-healable characteristics is the main goal of this review. The findings of this comprehensive review provide valuable information on the advancements and possibilities of TENGs, which opens the way for further research and advancement in this field. The discussion of life cycle evaluations of TENGs provides details on how well they perform in terms of the environment and identifies potential improvement areas. Additionally, the cost-effectiveness, social acceptability, and regulatory implications of self-healing TENGs are examined, as well as their economic and societal ramifications.

关键词： triboelectric nanogenerator (TENG)     self-healable nanomaterials     self-powered devices     energy    

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Increasing significance of advanced physical/chemical processes in the development and application of

RULKENS Wim

《环境科学与工程前沿（英文）》 2008年 第2卷 第4期   页码 385-396 doi: 10.1007/s11783-008-0073-1

摘要： The awareness of the problem of the scarcity of water of high quality has strongly changed the approach of wastewater treatment. Currently, there is an increasing need for the beneficial reuse of treated wastewater and to recover valuable products and energy from the wastewater. Because microbiological treatment methods are, only to a limited part, able to satisfy these needs, the role and significance of physical/chemical processes in wastewater treatment are gaining more and more interest. The specific future role and aim of the various physical/chemical treatment processes can be categorized in five groups: improvement of the performance of microbiological treatment processes, achievement of the high quality required for reuse of the effluent, recovery of valuable components and energy from the wastewater for beneficial reuse, desalination of brackish water and seawater, and treatment of concentrated liquid or solid waste residues produced in a wastewater treatment process. Development of more environmentally sustainable wastewater treatment chains in which physical/chemical processes play a crucial role, also requires application of process control and modeling strategies. This is briefly introduced by the elaboration of treatment scenarios for three specific wastewaters.

关键词： control     beneficial     valuable     scarcity     Development    

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CONCENTRATIONS AND FLUXES OF DISSOLVED NUTRIENTS IN THE YANGTZE RIVER: LONG-TERM TRENDS AND ECOLOGICAL

《农业科学与工程前沿（英文）》 2021年 第8卷 第4期   页码 559-567 doi: 10.15302/J-FASE -2020344

摘要：

Intensifying human activity in the Yangtze River basin has substantially increased nutrient concentrations in the Yangtze River Estuary, leading to degradation of the coastal environment. Analysis of nutrient determinations published over the past 50 years reveals a gradual decreasing trend in the concentrations and fluxes of dissolved silicate (DSi). However, both dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphate (DIP) concentrations have increased significantly since the 1970s. The frequency of and area covered by red tide outbreaks have increased greatly during this period, mainly due to changes in nutrient supply ratios [i.e., N/P (DIN/DIP), N/Si (DIN/DSi), P/Si (DIP/DSi)]. A strong correlation was found between the riverine DIN fluxes and the estimated DIN inputs from the major N sources, particularly fertilizers and atmospheric deposition. The data provide a comprehensive assessment of nutrients in the Yangtze River basin and their ecological impacts and indicate a potentially significant influence of atmospheric deposition on DIN loadings and fluxes.

 

关键词： atmospheric deposition / ecological impacts / nitrogen sources / nutrients / Yangtze delta    

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Research Trends in Information Technology Applications in Construction Safety Engineering and Management

Mirosɬaw J. Skibniewski

《工程管理前沿（英文）》 2014年 第1卷 第3期   页码 246-259 doi: 10.15302/J-FEM-2014034

摘要： Through analysis of articles published from 2000 to March 2014 in Automaton in Construction (AUTCON), an international research journal published by Elsevier, this paper summarizes the topics of research and the institutions worldwide where research was conducted in construction safety engineering and management. Seventy-one articles published during this time focused on Information Technology (IT) applications in this field were selected for analysis. The underlying research topics and their related IT implementations are discussed, and research trends in allied specialties are identified.

关键词： automation     international research journal     research trends     industrial safety engineering and management     construction technology     building engineering     information technology    

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Emergency strategies and trends in the management of liver trauma

null

《医学前沿（英文）》 2012年 第6卷 第3期   页码 225-233 doi: 10.1007/s11684-012-0186-6

摘要：

The liver is the most frequently injured organ during abdominal trauma. The management of hepatic trauma has undergone a paradigm shift over the past several decades, with mandatory operation giving way to nonoperative treatment. Better understanding of the mechanisms and grade of liver injury aids in the initial assessment and establishment of a management strategy. Hemodynamically unstable patients should undergo focused abdominal sonography for trauma, whereas stable patients may undergo computed tomography, the standard examination protocol. The grade of liver injury alone does not accurately predict the need for operation, and nonoperative management is rapidly becoming popular for high-grade injuries. Hemodynamic instability with positive focused abdominal sonography for trauma and peritonitis is an indicator of the need for emergent operative intervention. The damage control concept is appropriate for the treatment of major liver injuries and is associated with significant survival advantages compared with traditional prolonged surgical techniques. Although surgical intervention for hepatic trauma is not as common now as it was in the past, current trauma surgeons should be familiar with the emergency surgical skills necessary to manage complex hepatic injuries, such as packing, Pringle maneuver, selective vessel ligation, resectional debridement, and parenchymal sutures. The present review presents emergency strategies and trends in the management of liver trauma.

关键词： liver trauma     nonoperative management     operative management    

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LAND-USE INTENSIFICATION TRENDS IN THE RIO DE LA PLATA REGION OF SOUTH AMERICA: TOWARD SPECIALIZATION

《农业科学与工程前沿（英文）》 2021年 第8卷 第1期

摘要：

• Current intensification trends in the Rio de la Plata need urgent re-direction.

•Integrated crop-livestock systems reconcile food production with ecosystem services.

•Case studies validate recoupling as a sustainable way to ecological intensification.

 

The Rio de la Plata region comprises central Argentina, Uruguay, and southern Brazil. Modern agriculture developed around 1900 with recent decades being characterized by the advance of cropping areas over native grasslands. Highly specialized agriculture has decoupled crop and livestock production but has succeeded in intensifying yields. However, significant losses of ecosystem services have been reported. Thus, questions have been raised on the sustainability of this pathway. A glance at world regions that have experienced similar trends suggests that an urgent course correction is needed. A major concern has been the lack of diversity in regions with highly specialized agriculture, promoting renewed interest in integrated crop-livestock systems (ICLS), not only because ICLS are more diverse than specialized systems, but also because they are rare examples of reconciliation between agroecosystem intensification and environmental quality. Consequently, this paper discusses alternatives to redesign multifunctional landscapes based on ICLS. Recent data provide evidence that recoupling crop and animal production increases the resilience of nutrient cycling functions and economic indicators to external stressors, enabling these systems to face climate-market uncertainty and reconcile food production with the provision of diverse ecosystem services. Finally, these concepts are exemplified in case studies where this perspective has been successfully applied.

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From Green to Sustainability—Trends in the Assessment Methods of Green Buildings

Steve Hsueh-Ming Wang,Paula Williams,Jing Shi,Huojun Yang

《工程管理前沿（英文）》 2015年 第2卷 第2期   页码 114-121 doi: 10.15302/J-FEM-2015018

摘要： This research investigates recent developments in assessment methods of green buildings and compares the differences in rating systems among the United Kingdom, USA, and Germany. There are indications that the rating systems are moving from green buildings to sustainable buildings. In order to understand the recent research in academic areas, we survey the recent Ph.D. dissertations and literature related to green building assessment. Discussion is provided on the major research areas of green buildings, which cover accountability of life cycle cost, methodology for balancing the three pillars, and government vision and public policy.

关键词： green     sustainability     buildings     assessment     methods     rating systems    

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标题 作者 时间 类型 操作

Study on reformulation of fluid catalytic cracking gasoline and increasing production of light olefins

YAN Pingxiang, MENG Xianghai, GAO Jinsen, XU Chunming, SUI Zhiyu

期刊论文

A 14-year measurement of toxic elements in atmospheric particulates in Hong Kong from 1995 to 2008

Wei NIE,Tao WANG,Aijun DING,Xuehua ZHOU,Wenxing WANG

期刊论文

Influence of increasing numbers of RE-inverters on the power quality in the distribution grids: A PQ

Przemyslaw JANIK, Grzegorz KOSOBUDZKI, Harald SCHWARZ

期刊论文

Breeding strategies for increasing yield potential in super hybrid rice

Shihua CHENG,Xiaodeng ZHAN,Liyong CAO

期刊论文

Catalysis of semihydrogenation of acetylene to ethylene: current trends, challenges, and outlook

期刊论文

Mapping the trends and prospects of battery cathode materials based on patent landscape

期刊论文

Trends of environmental accidents and impact factors in China

Pengli XUE, Weihua ZENG

期刊论文

Study of mechanism of activating flux increasing weld penetration of AC A-TIG welding for aluminum alloy

HUANG Yong, FAN Ding, FAN Qinghua

期刊论文

Emerging trends in self-healable nanomaterials for triboelectric nanogenerators: A comprehensive review

期刊论文

Increasing significance of advanced physical/chemical processes in the development and application of

RULKENS Wim

期刊论文

CONCENTRATIONS AND FLUXES OF DISSOLVED NUTRIENTS IN THE YANGTZE RIVER: LONG-TERM TRENDS AND ECOLOGICAL

期刊论文

Research Trends in Information Technology Applications in Construction Safety Engineering and Management

Mirosɬaw J. Skibniewski

期刊论文

Emergency strategies and trends in the management of liver trauma

null

期刊论文

LAND-USE INTENSIFICATION TRENDS IN THE RIO DE LA PLATA REGION OF SOUTH AMERICA: TOWARD SPECIALIZATION

期刊论文

From Green to Sustainability—Trends in the Assessment Methods of Green Buildings

Steve Hsueh-Ming Wang,Paula Williams,Jing Shi,Huojun Yang

期刊论文