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Mixing Intensification for Advanced Materials Manufacturing 被引量:1
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作者 Chao Yang Guang-Wen Chu +5 位作者 Xin Feng Yan-Bin Li Jie Chen Dan Wang Xiaoxia Duan Jian-Feng Chen 《Engineering》 2025年第1期135-144,共10页
The mixing process plays a pivotal role in the design,optimization,and scale-up of chemical reactors.For most chemical reactions,achieving uniform and rapid contact between reactants at the molecular level is crucial.... The mixing process plays a pivotal role in the design,optimization,and scale-up of chemical reactors.For most chemical reactions,achieving uniform and rapid contact between reactants at the molecular level is crucial.Mixing intensification encompasses innovative methods and tools that address the limitations of inadequate mixing within reactors,enabling efficient reaction scaling and boosting the productivity of industrial processes.This review provides a concise introduction to the fundamentals of multiphase mixing,followed by case studies highlighting the application of mixing intensification in the production of energy-storage materials,advanced optical materials,and nanopesticides.These examples illustrate the significance of theoretical analysis in informing and advancing engineering practices within the chemical industry.We also explore the challenges and opportunities in this field,offering insights based on our current understanding. 展开更多
关键词 Mixing intensification Chemical reaction Advanced materials High-end manufacturing
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Multi-Scale Influencing Factors and Prediction of Interannual Variability in Rapid Intensification Magnitude of Northwest Pacific Tropical Cyclones
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作者 LI Yu-meng ZHAN Rui-fen DING Yi-hui 《Journal of Tropical Meteorology》 2025年第1期75-86,共12页
The rapid intensification(RI)magnitude of tropical cyclones(TCs)over the western North Pacific(WNP)exhibits significant interannual variability and is influenced by multiple factors across various scales.These factors... The rapid intensification(RI)magnitude of tropical cyclones(TCs)over the western North Pacific(WNP)exhibits significant interannual variability and is influenced by multiple factors across various scales.These factors primarily include:interannual factors—sea surface temperature(SST)in key regions of the WNP,eastern Indian Ocean SST,El Niño-Southern Oscillation(ENSO),South Pacific Subtropical Dipole(SPSD),and western Pacific teleconnection;decadal factors—Atlantic Multidecadal Oscillation(AMO)and Pacific Decadal Oscillation(PDO);and longer-term factor—global warming.This study systematically analyzes these factors and their potential impacts,quantitatively assessing their relative importance.A statistical prediction model for the WNP TC-RI magnitude is developed based on ridge regression methods.The results indicate that the influence of these factors on the RI magnitude is closely related to the large-scale thermodynamic and dynamic conditions.Among them,the SPSD plays the most critical role in the interannual variability of the RI magnitude,followed by global warming and the AMO.Further analysis reveals that the statistical prediction model based on multiple factors demonstrates good predictive skill for the interannual variability of the TC RI magnitude. 展开更多
关键词 western North Pacific tropical cyclone rapid intensification interannual variability multis-cale factors
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Understanding the initial conditions contributing to the rapid intensification of typhoons through ensemble sensitivity analysis
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作者 Yixuan Ren Lili Lei +2 位作者 Jian-Feng Gu Zhe-Min Tan Yi Zhang 《Atmospheric and Oceanic Science Letters》 2025年第2期36-42,共7页
While steady improvements have been achieved for the track forecasts of typhoons,there has been a lack of improvement for intensity forecasts.One challenge for intensity forecasts is to capture the rapid intensificati... While steady improvements have been achieved for the track forecasts of typhoons,there has been a lack of improvement for intensity forecasts.One challenge for intensity forecasts is to capture the rapid intensification(RI),whose nonlinear characteristics impose great difficulties for numerical models.The ensemble sensitivity analysis(ESA)method is used here to analyze the initial conditions that contribute to typhoon intensity forecasts,especially with RI.Six RI processes from five typhoons(Chaba,Haima,Meranti,Sarika,and Songda)in 2016,are applied with ESA,which also gives a composite initial condition that favors subsequent RI.Results from individual cases have generally similar patterns of ESA,but with different magnitudes,when various cumulus parameterization schemes are applied.To draw the initial conditions with statistical significance,sample-mean azimuthal components of ESA are obtained.Results of the composite sensitivity show that typhoons that experience RI in 24 h favor enhanced primary circulation from low to high levels,intensified secondary circulation with increased radial inflow at lower levels and increased radial outflow at upper levels,a prominent warm core at around 300 hPa,and increased humidity at low levels.As the forecast lead time increases,the patterns of ESA are retained,while the sensitivity magnitudes decay.Given the general and quantitative composite sensitivity along with associated uncertainties for different cumulus parameterization schemes,appropriate sampling of the composite sensitivity in numerical models could be beneficial to capturing the RI and improving the forecasting of typhoon intensity. 展开更多
关键词 TYPHOON Rapid intensification Ensemble sensitivity analysis Composite sensitivity
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Analysis of the Rapid Intensification Mechanism for a Super Arctic Cyclone Based on a New Surface Pressure Tendency Equation
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作者 Wei ZHONG Qian QIAN +3 位作者 Yao YAO Deyuan ZHANG Yuan SUN Huadong DU 《Advances in Atmospheric Sciences》 2025年第5期842-854,共13页
The synoptic process of a super Arctic cyclone in August 2016(AC16)is investigated based on the Weather Research and Forecasting(WRF)model,and the key factors affecting the rapid intensification(RI)of AC16 and their r... The synoptic process of a super Arctic cyclone in August 2016(AC16)is investigated based on the Weather Research and Forecasting(WRF)model,and the key factors affecting the rapid intensification(RI)of AC16 and their relative contributions are analyzed by diagnosing a new surface pressure tendency equation(SPTE).The major physical mechanisms behind the two RI stages of AC16 are revealed.The trajectory,intensity changes,and structural characteristics of AC16 are well simulated by the WRF model.A diagnosis based on the SPTE promisingly reproduces the two RI stages of AC16.The leading factor that influenced the intensity of AC16 was identified to be the air-column potential temperature tendency,while the pressure change at the upper boundary had less of an impact.Further analysis reveals that the horizontal potential temperature advection was the decisive factor in a warming of the air column.Specifically,the upper-level warm advection generated by the strong wind field of the upper-level jet played a dominant role in warming the air column,which caused the initial RI of AC16.The AC16 movement into a strong potential temperature gradient generated by tropopause polar vortices increased the upper-level warm advection,which warmed the air column and thereby induced the second RI of AC16.However,the net effect of vertical potential temperature advection and latent heating,as well as radiation processes,caused a cooling of the air column and thereby negatively contributed to the RI of AC16. 展开更多
关键词 Arctic cyclone rapid intensification surface pressure tendency equation tropopause polar vortices
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Sustainable intensification for land space utilization system:Theoretical construction and application implications
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作者 XU Weiyi LIU Jing 《Journal of Geographical Sciences》 2025年第12期2511-2535,共25页
Existing studies have mostly focused on sustainable intensification(SI)in agricultural systems,while neglecting the integrated analysis of SI for the land space utilization system(LSUS).This has resulted in a lack of ... Existing studies have mostly focused on sustainable intensification(SI)in agricultural systems,while neglecting the integrated analysis of SI for the land space utilization system(LSUS).This has resulted in a lack of systematic solutions in balancing sustainable resource utilization and environmental protection.This study reviewed SI's conceptual framework and evaluation,identified the gaps,and proposed an analytical framework of SI with clear logic and modeling processes for LSUS.Key findings include:(1)Resource competition and ecosystem pressures have highlighted the need to extend traditional agriculture-focused SI to LSUS and establish a clear quantitative evaluation framework for SI;(2)SI for LSUS refers to a system state in which a specific sub-system produces its dominant functions with resource savings,reduced environmental impact,efficient function output,and stable/enhanced function provision,while sub-systems evolve in a coordinated and orderly manner;(3)The assessment framework of SI for LSUS clarifies modeling processes,suggested indicators,methods and scale hierarchy system to help policymakers identify SI priorities across scales,informing strategies to balance agricultural,socioeconomic,and ecosystem goals.This study overcomes the limitations of traditional SI,providing crucial insights for tracking SI performance and identifying barriers in LSUS to enlighten the sustainable land use and management practices. 展开更多
关键词 sustainable intensification land space utilization system agriculture-economy-ecology ecosystem services and functions supply efficiency of functions and services
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Science and Technology Backyard: A novel approach to empower smallholder farmers for sustainable intensification of agriculture in China 被引量:20
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作者 JIAO Xiao-qiang ZHANG Hong-yan +3 位作者 MA Wen-qi WANG Chong LI Xiao-lin ZHANG Fu-suo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第8期1657-1666,共10页
Sustainable feeding of the growing population in China without ecological destabilization is a grand challenge. In this populous country where agriculture is dominated by smallholder farming, developing innovative tec... Sustainable feeding of the growing population in China without ecological destabilization is a grand challenge. In this populous country where agriculture is dominated by smallholder farming, developing innovative technology and translating scientific knowledge into action for smallholder farmers is a crucial step in addressing this challenge. Here, we present a novel approach for technology innovation and dissemination to achieve sustainable intensification in the fields of smallholder farmers. The Science and Technology Backyard(STB) is a hub in a rural area that links knowledge with practices to promote technology innovation and exchange. In this study, the framework and functions of STB are introduced, and the key implications for sustainable intensification across millions of smallholder farmers are explicitly stated:(i) develop innovative technology based on stated demands of farmers;(ii) disseminate technology by innovative social service models though combined top-down approaches with bottom-up measures to enable smallholders in rural areas. This paper provides a perspective on transformation of small-scale agriculture toward sustainable intensification in China and useful knowledge applicable to other developing countries. 展开更多
关键词 SMALLHOLDER FARMERS SUSTAINABLE intensification TECHNOLOGY innovation TECHNOLOGY transfer Science and TECHNOLOGY BACKYARD
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Dynamic trends and driving forces of land use intensification of cultivated land in China 被引量:25
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作者 WANG Guogang LIU Yansui +1 位作者 LI Yurui CHEN Yangfen 《Journal of Geographical Sciences》 SCIE CSCD 2015年第1期45-57,共13页
The aim of this study is to establish several important factors representing land use intensification in cultivated land (denoted by ClI), using a multi-dimensional approach to achieve realistic and practical cultiv... The aim of this study is to establish several important factors representing land use intensification in cultivated land (denoted by ClI), using a multi-dimensional approach to achieve realistic and practical cultivated land use policies in China. For this reason, the theoretical framework was first built to explain the changes of land use intensification in the cultivated land, and then the variables and index were further developed for the purpose of characterizing the dynamic trends and driving forces of the land use intensification in the cultivated land at the provincial level. The study results indicate that the extent of Cll significantly increased during the period of 1996 to 2008, due to the extensive use of fertilizers, machinery and pesticide, increased labor and capital input, and intensified land use. Moreover, the principal component regression results show that the productivity of cultivated land, economic benefits of cultivated land, labor productivity, and land use conversion are the main factors affecting the village development. The first three factors play a positive role, while the last one has a negative effect on the land use intensification in the cultivated land. According to these results, the main policies for sustainable intensification in cultivated land are proposed. First, the sustainable pathways for intensification should be adopted to reduce the unsustainable uses of chemical fertilizer, agricultural chemicals, etc. Second, the conditions for agricultural production should be further improved to increase the cultivated land productivity. Third, it is very necessary and helpful for improving labor productivity and land use efficiency from the viewpoint of accelerated the cultivated land circulation. The last step is to positively affect the production activities of peasants by means of reforming the subsidy standards. 展开更多
关键词 cultivated land land use intensification spatial pattern FACTORS China
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Impacts of the Diurnal Cycle of Radiation on Tropical Cyclone Intensification and Structure 被引量:11
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作者 GE Xuyang MA Yue +1 位作者 ZHOU Shunwu Tim LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第6期1377-1385,共9页
To investigate the impacts of the diurnal cycle on tropical cyclones (TCs),a set of idealized simulations were conducted by specifying different radiation (i.e.,nighttime-only,daytime-only,full diurnal cycle).It w... To investigate the impacts of the diurnal cycle on tropical cyclones (TCs),a set of idealized simulations were conducted by specifying different radiation (i.e.,nighttime-only,daytime-only,full diurnal cycle).It was found that,for an initially weak storm,it developed faster during nighttime than daytime.The impacts of radiation were not only on TC intensification,but also on TC structure and size.The nighttime storm tended to have a larger size than its daytime counterparts.During nighttime,the radiative cooling steepened the lapse rate and thus reduced the static stability in cloudy regions,enhancing convection.Diabatic heating associated with outer convection induced boundary layer inflows,which led to outward expansion of tangential winds and thus increased the storm size. 展开更多
关键词 solar shortwave radiation tropical cyclone STRUCTURE intensification diurnal cycle
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Process intensification and energy saving of reactive distillation for production of ester compounds 被引量:8
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作者 Chunli Li Cong Duan +1 位作者 Jing Fang Hongshi Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第6期1307-1323,共17页
Reactive distillation(RD) process is an innovative hybrid process combining reaction with distillation, which has recently come into sharp focus as a successful case of process intensification. Considered as the most ... Reactive distillation(RD) process is an innovative hybrid process combining reaction with distillation, which has recently come into sharp focus as a successful case of process intensification. Considered as the most representative case of process intensification, it has been applied for many productions, especially for production of ester compounds. However, such problems existing in the RD system for ester productions are still hard to solve,as the removal of the water which comes from the esterification, and the separation of the azeotropes of ester–alcohol(–water). Many methods have been studying on the process to solve the problems resulting in further intensification and energy saving. In this paper, azeotropic–reactive distillation or entrainer enhanced reactive distillation(ERD) process, reactive extractive distillation(RED) process, the method of co-production in RD process, pressure-swing reactive distillation(PSRD) process, reactive distillation–pervaporation coupled process(RD–PV), are introduced to solve the problems above, so the product(s) can be separated efficiently and the chemical equilibrium can be shifted. Dividing-wall column(DWC) structure and novel methods of loading catalyst are also introduced as the measures to intensify the process and save energy. 展开更多
关键词 REACTIVE DISTILLATION PROCESS intensification PROCESS COUPLING THERMAL COUPLING
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A Review of Techniques for the Process Intensification of Fluidized Bed Reactors 被引量:12
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作者 张维 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第4期688-702,共15页
Fluidized beds enable good solids mixing,high rates of heat and mass transfer,and large throughputs,but there remain issues related to fluidization quality and scale-up.In this work I review modification techniques fo... Fluidized beds enable good solids mixing,high rates of heat and mass transfer,and large throughputs,but there remain issues related to fluidization quality and scale-up.In this work I review modification techniques for fluidized beds from the perspective of the principles of process intensification(PI),that is,effective bubbling suppression and elutriation control.These techniques are further refined into(1)design factors,e.g.modifying the bed configuration,or the application of internal and external forces,and(2)operational factors,including altering the particle properties(e.g.size,density,surface area)and fluidizing gas properties(e.g.density,viscosity,or velocity).As far as two proposed PI principles are concerned,our review suggests that it ought to be possible to gain improvements of between 2 and 4 times over conventional fluidized bed designs by the application of these techniques. 展开更多
关键词 process intensification FLUIDIZATION fluidized bed reactor
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Process Intensification in Pneumatically Agitated Slurry Reactors 被引量:8
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作者 Shujun Geng Zai-Sha Mao +1 位作者 Qingshan Huang Chao Yang 《Engineering》 SCIE EI 2021年第3期304-325,共22页
Pneumatically agitated slurry reactors,including bubble column reactors and airlift loop reactors(ALRs),are important gas-liquid-solid multiphase reactors.These reactors have been widely applied in many processes,espe... Pneumatically agitated slurry reactors,including bubble column reactors and airlift loop reactors(ALRs),are important gas-liquid-solid multiphase reactors.These reactors have been widely applied in many processes,especially in the biological fermentation and energy chemical industry,due to their low shear stress,good mixing,perfect mass-/heat-transfer properties,and relatively low costs.To further improve the performance of slurry reactors(i.e.,mixing and mass/heat transfer)and to satisfy industrial require-ments(e.g.,temperature control,reduction of back-mixing,and product separation),the process intensi-fication of slurry reactors is essential.This article starts by reviewing the latest advancements in the intensification of mixing and mass/heat transfer in these two types of reactors.It then summarizes process-intensification methods for mixing and separation that allow continuous production in these slurry reactors.Process-intensification technology that integrates directional flow in an ALR with simple solid-liquid separation in a hydrocyclone is recommended for its high efficiency and low costs.This arti-cle also systematically addresses vital considerations and challenges,including flow regime discrimina-tion,gas spargers,solid particle effects,and other concerns in slurry reactors.It introduces the progress of numerical simulation using computational fluid dynamics(CFD)for the rational design of slurry reactors and discusses difficulties in modeling.Finally,it presents conclusions and perspectives on the design of industrial slurry reactors. 展开更多
关键词 Slurry reactors Pneumatic agitation Bubble column Airlift loop reactor Process intensification Solid particles
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Influence of intensification pressures on pores in die-cast ADC12 alloys 被引量:5
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作者 Chun-tao Wang Jie Yao +1 位作者 Hai-dong Zhao Run-sheng Yang 《China Foundry》 SCIE 2019年第3期184-189,共6页
Die casting process is widely applied in making Al parts. However, due to high speed of liquid metal flow in the die cavity, gases are prone to be entrapped in the filling, resulting in porosity defects. The X-ray com... Die casting process is widely applied in making Al parts. However, due to high speed of liquid metal flow in the die cavity, gases are prone to be entrapped in the filling, resulting in porosity defects. The X-ray computed tomography scanning technique was used to detect the pores in die-cast ADC12 alloys with different intensification pressures. The three-dimensional features of pores including pore size, number, sphericity have been obtained. The effect of different intensification pressures on two different kinds of pores, namely gas-pores and shrinkage pores, was analyzed. The results show that with increasing the pressure, the pore fractions and quantity gradually decrease. When the pressure increased to 85 MPa, the pores from gas entrapment during the mold filling were compressed, leading to a lower porosity fraction. The pressure cannot affect the pores in the samples with a thin wall (2 mm) due to a great solidification rate. 展开更多
关键词 die CASTING intensification pressure POROSITY X-ray COMPUTED tomography
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Microinterface intensification in hydrogenation and air oxidation processes 被引量:5
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作者 Hongliang Qian Hongzhou Tian +7 位作者 Guoqiang Yang Gaodong Yang Lei Li Feng Zhang Zheng Zhou Weihua Huang Yufu Chen Zhibing Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第10期292-300,共9页
Hydrogenations and air oxidations usually have low apparent reaction rate,generally controlled by mass transfer rate,and widely exist in the modern chemical manufacturing process.The key to increase the mass transfer ... Hydrogenations and air oxidations usually have low apparent reaction rate,generally controlled by mass transfer rate,and widely exist in the modern chemical manufacturing process.The key to increase the mass transfer rate is the reduction of the liquid film resistance 1/kLa.In this work,the original concept of microinterface intensification for mass transfer and then for these reactions has been proposed.We derived the regulation model and set up the mathematical calculation method of micron-scale gas-liquid interface structure on mass transfer and reaction,designed the mechanical energy exchange device that can produce gas-liquid microinterface system on a large scale,and established the OMIS system which is able on line to measure the diameter and distribution of millions of microbubbles,interface area a and mass transfer film thicknessδM,as well as developed a series of microinterface intensified reactor systems(MIRs)for the applications of hydrogenation and air oxidation processes.It is believed that this research will provide an up-to-date development for the intensification of hydrogenation and air oxidation reactions. 展开更多
关键词 Hydrogenation andoxidation Microinterface intensification Mass transfercoefficient Structure-effect regulation Online measurement
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Sustainable Intensification of Cultivated Land Use and Its Influencing Factors at the Farming Household Scale: A Case Study of Shandong Province, China 被引量:6
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作者 NIU Shandong LYU Xiao +2 位作者 GU Guozheng ZHOU Xiaoping PENG Wenlong 《Chinese Geographical Science》 SCIE CSCD 2021年第1期109-125,共17页
Promoting the sustainable intensification of cultivated land use(SICL) has become crucial for ensuring a sufficient supply of grain and important agricultural products, as well as for the sustainable use of resources.... Promoting the sustainable intensification of cultivated land use(SICL) has become crucial for ensuring a sufficient supply of grain and important agricultural products, as well as for the sustainable use of resources. Taking widely used areas of Shandong Province in China as examples, an analytical scale and level framework for SICL is constructed in this study. It measures the level of SICL through material flow analysis, constructs Tobit models to analyze the influencing factors of SICL at the farming household scale,and analyzes the transition mechanisms of SICL. The results show that the overall level of SICL in Shandong Province is low, and the spatial distribution is uneven. There are relatively more farmers participating in unsustainable intensification than in medium or low levels of SICL, with farmers working at a high level of SICL making up the smallest proportion. The factors that determine the level of SICL at which farmers work vary significantly. More male farmers operate at a low SICL level than female farmers, while females outnumber males at a high SICL level. This is mainly related to the regional distribution of age and population. Meanwhile, with larger cultivated land areas, there is a lower degree of land fragmentation, with a higher level of SICL corresponding to a smaller distance to the nearest town closer within 1–5 km from the town center. We can see the level of SICL and its processes themselves are closely related to time and space scales. Based on the above analysis, it is necessary to clarify the standard processes of SICL to adapt them to local conditions. This includes instructing managers on how to improve resource utilization, increase the sustainable development of cultivated land and establish a comprehensively efficient and functional SICL mechanism. The sustainable intensification of cultivated land use and its specific application in the new era are conducive to enriching the frontier theories and methodology of sustainable development, and are of great significance to the advancement of green agriculture and the decision-making of rural high-quality development. 展开更多
关键词 cultivated land use sustainable intensification farming household scale material flow analysis
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Intensification of adsorption process by using the pyrolytic char from waste tires to remove chromium(Ⅵ) from wastewater 被引量:4
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作者 ZHOUJie YANGYong-rong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第6期1016-1019,共4页
Pyrolysis has the potential of transforming waste into valuable recyclable products. Pyrolytic char(PC) is one of the most important products from the pyrolysis of used tires. One of the most significant applications ... Pyrolysis has the potential of transforming waste into valuable recyclable products. Pyrolytic char(PC) is one of the most important products from the pyrolysis of used tires. One of the most significant applications for pyrolytic char recovered is used for the removal of Cr(Ⅵ) in the wastewater effluent to control waste by waste. The surface chemistry properties of surface element distribution / concentration and chemical structure were examined for the pyrolytic char and the commercial activated carbon(CAC) respectively. The results showed that surfaces of PC possesses a large amount of ester and hydrocarbon graft, whereas there are mainly carbon functional components of C—OH, C O and COOH on the surface of CAC. Therefore the surface electronegativity of PC is lower than that of CAC in the water. The repulsive interactions between the surfaces of PC and the negatively charged Cr(Ⅵ) ion are weaker than that of CAC, which results in an intensification of the adsorption process by the utilization of PC. The adsorption isotherms of Cr(Ⅵ) ion on the two kinds of carbons were determined experimentally. The larger adsorption amount on the PC in the case of Cr(Ⅵ) may be attributed mainly to its special surface micro-chemical environment. The mechanism of the removal Cr(Ⅵ) from aqueous solution was assumed to be the integration of adsorption and redox reaction. The adsorption was the rate-controlled step for Cr(Ⅵ) removal. The adsorption of Cr(Ⅵ) was identified as pseudo-second-order kinetics. The rate constants of adsorption were evaluated. 展开更多
关键词 waste tire pyrolytic char surface chemistry properties Cr(Ⅵ) wastewater treatment kinetics intensification
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Improving the phenotypic expression of rice genotypes:Rethinking “intensification” for production systems and selection practices for rice breeding 被引量:3
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作者 Norman Uphoff Vasilia Fasoula +2 位作者 Anas Iswandi Amir Kassam Amod K.Thakur 《The Crop Journal》 SCIE CAS CSCD 2015年第3期174-189,共16页
Intensification in rice crop production is generally understood as requiring increased use of material inputs: water, inorganic fertilizers, and agrochemicals. However, this is not the only kind of intensification ava... Intensification in rice crop production is generally understood as requiring increased use of material inputs: water, inorganic fertilizers, and agrochemicals. However, this is not the only kind of intensification available. More productive crop phenotypes, with traits such as more resistance to biotic and abiotic stresses and shorter crop cycles, are possible through modifications in the management of rice plants, soil, water, and nutrients, reducing rather than increasing material inputs. Greater factor productivity can be achieved through the application of new knowledge and more skill, and(initially) more labor, as seen from the System of Rice Intensification(SRI), whose practices are used in various combinations by as many as 10 million farmers on about 4 million hectares in over 50 countries. The highest yields achieved with these management methods have come from hybrids and improved rice varieties, confirming the importance of making genetic improvements. However,unimproved varieties are also responsive to these changes, which induce better growth and functioning of rice root systems and more abundance, diversity, and activity of beneficial soil organisms. Some of these organisms as symbiotic endophytes can affect and enhance the expression of rice plants' genetic potential as well as their phenotypic resilience to multiple stresses, including those of climate change. SRI experience and data suggest that decades of plant breeding have been selecting for the best crop genetic endowments under suboptimal growing conditions, with crowding of plants that impedes their photosynthesis and growth, flooding of rice paddies that causes roots to degenerate and forgoes benefits derived from aerobic soil organisms, and overuse of agrochemicals that adversely affect these organisms as well as soil and human health. This review paper reports evidence from research in India and Indonesia that changes in crop and water management can improve the expression of rice plants' genetic potential, thereby creating more productive and robustphenotypes from given rice genotypes. Data indicate that increased plant density does not necessarily enhance crop yield potential, as classical breeding methods suggest. Developing cultivars that can achieve their higher productivity under a wide range of plant densities—breeding for density-neutral cultivars using alternative selection strategies—will enable more effective exploitation of available crop growth resources. Density-neutral cultivars that achieve high productivity under ample environmental growth resources can also achieve optimal productivity under limited resources, where lower densities can avert crop failure due to overcrowding. This will become more important to the extent that climatic and other factors become more adverse to crop production. Focusing more on which management practices can evoke the most productive and robust phenotypes from given genotypes is important for rice breeding and improvement programs since it is phenotypes that feed our human populations. 展开更多
关键词 EXPRESSION of genetic potential RICE PHENOTYPES SELECTION criteria for plant breeding SELECTION efficiency System of RICE intensification
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Sensitivity of Tropical Cyclone Intensification to Inner-Core Structure 被引量:4
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作者 GE Xuyang XU Wei ZHOU Shunwu 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第10期1407-1418,共12页
In this study, the dependence of tropical cyclone (TC) development on the inner-core structure of the parent vortex is examined using a pair of idealized numerical simulations. It is found that the radial profile of... In this study, the dependence of tropical cyclone (TC) development on the inner-core structure of the parent vortex is examined using a pair of idealized numerical simulations. It is found that the radial profile of inner-core relative vorticity may have a great impact on its subsequent development. For a system with a larger inner-core relative vorticity/inertial stability, the conversion ratio of the diabatic heating to kinetic energy is greater. Furthermore, the behavior of the convective vorticity eddies is likely modulated by the system-scale circulation. For a parent vortex with a relatively higher inner-core vorticity and larger negative radial vorticity gradient, convective eddy formation and radially inward propagation is promoted through vorticity segregation. This provides a greater potential for these small-scale convective cells to self-organize into a mesoscale inner-core structure in the TC. In turn, convectively induced diabatic heating that is close to the center, along with higher inertial stability, efficiently enhances system-scale secondary circulation. This study provides a solid basis for further research into how the initial structure of a TC influences storm dynamics and thermodynamics. 展开更多
关键词 tropical cyclone intensification inner-core structure
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Luminescence intensification of lanthanide complexes by silver nanoparticles incorporated in sol-gel matrix 被引量:3
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作者 Renata Reisfeld Marek Pietraszkiewicz +1 位作者 Tsiala Saraidarov Viktoria Levchenko 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第4期544-549,共6页
We present how the luminescence of europium RR-2-P-oxides complexes can be increased by interaction of electronic levels of the complex with the radiation field of silver nanoparticles (NPs). The procedure by which ... We present how the luminescence of europium RR-2-P-oxides complexes can be increased by interaction of electronic levels of the complex with the radiation field of silver nanoparticles (NPs). The procedure by which silver NPs are formed in a sol-gel polyurethane matrix precursor was elaborated. The formed Ag NPs were combined with Eu complex incorporated in ormocer matrix. The emission spectra of the complexes without silver NPs were compared with spectra of the same complexes with addition of silver NPs. As the result of the interaction of the electronic levels of lanthaaide ligands with silver plasmons, dramatic increase of luminescence was observed. 展开更多
关键词 luminescence intensification Eu RR-2-P-oxides complexes silver nanoparticles silica-polyurethane zirconia-glymo particles size distribution rare earths
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Factors in fluencing farmers' participation in crop intensification program in Rwanda 被引量:3
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作者 Alphonse Nahayo Morris O.Omondi +3 位作者 ZHANG Xu-hui LI Lian-qing PAN Gen-xing Stephen Joseph 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第6期1406-1416,共11页
The crop intensification program(CIP)was introduced in Rwanda in 2007 by the Ministry of Agriculture and Animal Resources(MINAGRI),Rwanda,as a solution to the land fragmentation,low use of agricultural inputs and ... The crop intensification program(CIP)was introduced in Rwanda in 2007 by the Ministry of Agriculture and Animal Resources(MINAGRI),Rwanda,as a solution to the land fragmentation,low use of agricultural inputs and low access to extension services.However,due to the voluntary nature of farmers’participation and their reluctance to participate,this study aimed at assessing the factors that influence their participation.Data were collected from 340 respondents through a household survey in Mayange and Rusarabuye sectors.Descriptive statistics and binary logistic regression model were used to analyze the data.Results show that the factors that significantly influenced the farmers’participation in the CIP include gender,non-farm income,farmland size,farming experience,land acquisition means,market access,trust and agro-ecological conditions.In fact,the non-farm income significantly increased the farmers’decisions to participate in the CIP(P〈0.001)as it eases the financial capital needed to invest in the CIP activities.On the land acquisition means,the farmers who inherited or bought the land positively and significantly participated in the CIP(P〈0.05)because they had the land tenure security.However,the participation in the CIP was hindered by inadequate irrigation and mechanization facilities,lack of farmers’participation in the CIP planning process,inadequate extension services,inadequate agricultural inputs and inadequate post-harvest technologies.Closer collaboration between farmers,local leaders,extension agents and agricultural service providers as well as the farmers’practical skills in irrigation and mechanization could enhance the participation to the program.Therefore,there is a need on the part of policymakers to empower farmers with adequate knowledge on better cropping practices and agricultural technologies through appropriate extension services and bottom-up based program. 展开更多
关键词 chemical fertilizers crop intensification program extension services improved seeds post-harvest techniques institutional factors socio-economic factors constraints
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Impact of agricultural intensification on soil organic carbon" A study using DNDC in Huantai County, Shandong Province, China 被引量:3
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作者 LIAO Yan WU Wen-liang +1 位作者 MENG Fan-qiao LI Hu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第6期1364-1375,共12页
Using the biogeochemical model den itrification/decomposition (DN DC), the dynamic changes of soil organic carbon (SOC) of farmland from the 1980s to 2030s were investigated in Huantai County, a typical intensive ... Using the biogeochemical model den itrification/decomposition (DN DC), the dynamic changes of soil organic carbon (SOC) of farmland from the 1980s to 2030s were investigated in Huantai County, a typical intensive agricultural region in the Huang- Huai-Hai Plain of China. Prior to modelling, validation of the DNDC model against field data sets of SOC from Quzhou Experimental Station in the Huang-Huai-Hai Plain was conducted at the site scale. We compared the simulated results with the observed SOC in Huantai County during 1982-2011 under two different classification methods of simulation unit (the first method integrated soil type and land use of Huantai County to form the overlapped modeling units; the second selected the 11 administrative towns as the modeling units), and achieved a high accuracy in the model simulation with the improvement of the model parameters. Regional SOC (0-20 cm) density and stocks for Huantai County in the years 2012-2031 were predicted under different scenarios of farming management. Compared with current management practices, optimized fertilization (20% decrease of mineral N), crop straw incorporation (90%) and appropriate animal manure input (40 kg N ha-1 yr-1) could achieve the highest level of SOC density (56.8% higher than 2011) in the period of 2012-2031. The research highlighted the importance of crop straw incorporation, optimized N fertilization and integration of crop production with ani- mal husbandry on the farmland carbon sequestration for maintaining a high land productivity in the Huang-Huai-Hai Plain. 展开更多
关键词 agricultural intensification soil organic carbon DNDC nitrogen fertilizer straw incorporation animal manure
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