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Experimental and numerical investigation of liquid-solid binary fluidized beds： Radioactive particle tracking technique and dense discrete phase model simulations

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Particuology 2017年第4期15卷 112-122页

作者： Varsha jain Lipika Kalo Deepak Kumar Harish j. Pant Rajesh K. Upadhyay Department of Chemical Engineering Indian Institute of Technology Guwahati Assam 781039 India Isotope Production and Applications Division Bhabha Atomic Research Centre Trombay Mumbai 400085 India

Liquid-solid binary fluidized beds are widely used in many industries. However, the flow behavior of such beds is not well understood due to the lack of accurate experimental and numerical data. In the current study, the behavior of monodisperse and binary liquid-solid fluidized beds of the same density but dif- ferent sizes is investigated using radioactive particle tracking （RPT） technique and a dense discrete phase model （DDPM）. Experiments and simulations are performed in monodisperse fluidized beds containing two different sizes of glass beads （0.6 and I mm） and a binary fluidized bed of the same particles for vari- ous bed compositions. The results show that both RPT and DDPM can predict the mixing and segregation pattern in liquid-solid binary fluidized beds. The mean velocity predictions of DDPM are in good agree- ment with the experimental findings for both monodisperse and binary fluidized beds. However, the axial root mean square velocity predictions are only reasonable for bigger particles. Particle-particle interac- tions are found to be critical for predicting the flow behavior of solids in liquid-solid binary fluidized beds.

关键词： Binary bed Liquid-solid flow Fluidized bed Radioactive particle tracking Dense discrete phase model

REHEATING TEMPERATURE CONTRAST AND MICROSTRUCTURES OF 7075 Al ALLOY CAST BY LIQUIDUS SEMI-CONTINUOUS CASTING

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Acta Metallurgica Sinica(English Letters) 2002年第6期15卷 551-555页

作者： j. Dong, G.M. Lu and j.Z. CuiThe Key Lab. of Electromagnetic Processing of Material, Ministry of Education, Northeastern University, Shenvane 110004, China The Key Lab. of Electromagnetic Processing of Material. Ministry of Education Northeastern University

In this study, reheating of liquidus semi-continuous cast billets of 7075 Al alloy was carried out in a resistance furnace, and the temperature contrast of the outer and the center of the reheated billets was investigated, then the reheating microstructures were investigated. Results show that: the difference of temperature between the outer and center is small and the difference of their microstructures are also small. During reheating at 576℃ the spheroidization of grains is significant after 5min and no rosettes are visible after 20min by optical microscopy. Similar observations were madeon materials reheated at 596℃, but the ripening process is faster. The grains growup to 30-60μm, fine enough for thixoforming.

关键词： reheating 7075 Al alloy liquidus casting micro structure

Forensic Science and its Limitations in Rape and Murder Cases in India

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journal of Forensic Science and Medicine 2023年第1期9卷 91-97页

作者： j Lakshmi Charan K Sita Manikyam Dr.B.R.Ambedkar College of Law Andhra UniversityVisakhapatnamAndhra PradeshIndia

Forensic science plays a significant role in crime scene analysis and other evidence collection(such as clothes,cigarette butts,blood,semen,hair,etc.,)to scientifically establish the accused’s *** rape and murder cases,DNA tests confirm the victim’s *** provides certain evidence that is helpful in the speedy investigation and conclusion of a ***,it is not a foolproof science and it has certain ***,the first responders,such as the Crime Laboratory Ultimate Evidence System team and the forensic experts,must keep these limitations in mind during sample collection and examination,otherwise,it may lead to incorrect *** incorrect results may be obtained due to insufficient sample quantity,improper collection methods,or delay in an *** is highly recommended to implement standard operating procedure guidelines,failing which the admissibility of such forensic evidence to prove beyond all reasonable doubts is at ***,the court shall acquit the accused giving him the benefit of *** article focuses on the applicability and limitations of forensic science in the Indian Criminal justice System and the need to adopt due protocols to yield viable results.

关键词： Crime scene forensic science Indian criminal justice system rape standard operating procedure

Adaptive green traffic signal controlling using vehicular communication

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Frontiers of Information Technology & Electronic Engineering 2017年第3期18卷 373-393页

作者： Erfan SHAGHAGHI Mohammad Reza jABBARPOUR Rafidah MD NOOR Hwasoo YEO jason j.jUNG Department of Computer Systems and Technology University of Malaya Department of Computer Engineering Islamic Azad UniversityNorth Tehran Branch Department of Civil and Environmental Engineering Korea Advanced Institute of Science and Technology Department of Computer Engineering Chung-Ang University

The importance of using adaptive traffic signal control for figuring out the unpredictable traffic congestion in today's metropolitan life cannot be overemphasized. The vehicular ad hoc network(VANET), as an integral component of intelligent transportation systems(ITSs), is a new potent technology that has recently gained the attention of academics to replace traditional instruments for providing information for adaptive traffic signal controlling systems(TSCSs). Meanwhile, the suggestions of VANET-based TSCS approaches have some weaknesses:(1) imperfect compatibility of signal timing algorithms with the obtained VANET-based data types, and(2) inefficient process of gathering and transmitting vehicle density information from the perspective of network quality of service(Qo S). This paper proposes an approach that reduces the aforementioned problems and improves the performance of TSCS by decreasing the vehicle waiting time, and subsequently their pollutant emissions at intersections. To achieve these goals, a combination of vehicle-to-vehicle(V2V) and vehicle-to-infrastructure(V2I) communications is used. The V2 V communication scheme incorporates the procedure of density calculation of vehicles in clusters, and V2 I communication is employed to transfer the computed density information and prioritized movements information to the road side traffic controller. The main traffic input for applying traffic assessment in this approach is the queue length of vehicle clusters at the intersections. The proposed approach is compared with one of the popular VANET-based related approaches called MC-DRIVE in addition to the traditional simple adaptive TSCS that uses the Webster method. The evaluation results show the superiority of the proposed approach based on both traffic and network Qo S criteria.

关键词： Vehicular ad hoc network(VANET) Intelligent transportation systems(ITSs) Clustering Adaptive traffic signal control Traffic controller Fuel consumption

Deficit Irrigation as a Strategy to Save Water:Physiology and Potential Application to Horticulture

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journal of Integrative Plant Biology 2007年第10期49卷 1421-1434页

作者： j.Miguel Costa Maria F.Ortuo M.Manuela Chaves InstitutoSuperior de Agronomia Universidade Técnica de LisboaTapada da Ajuda1349-017 LisboaPortugal Laboratório de Ecofisiologia MolecularInstituto de Tecnologia Química e BiológicaApartado 1272780-901 OeirasPortugal Instituto

Water is an increasingly scarce resource worldwide and irrigated agriculture remains one of the largest and most inefficient users of this resource. Low water use efficiency （WUE） together with an increased competition for water resources with other sectors （e.g. tourism or industry） are forcing growers to adopt new irrigation and cultivation practices that use water more judiciously. In areas with dry and hot climates, drip irrigation and protected cultivation have improved WUE mainly by reducing runoff and evapotranspiration losses. However, complementary approaches are still needed to increase WUE in irrigated agriculture. Deficit irrigation strategies like regulated deficit irrigation or partial root drying have emerged as potential ways to increase water savings in agriculture by allowing crops to withstand mild water stress with no or only marginal decreases of yield and quality. Grapevine and several fruit tree crops seem to be well adapted to deficit irrigation, but other crops like vegetables tend not to cope so well due to losses in yield and quality. This paper aims at providing an overview of the physiological basis of deficit irrigation strategies and their potential for horticulture by describing the major consequences of their use to vegetative growth, yield and quality of different crops （fruits, vegetables and ornamentals）.

关键词： deficit irrigation horticulture partial rootzone drying regulated deficit irrigation water saving.

From Slater to Mott physics by epitaxially engineering electronic correlations in oxide interfaces

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npj Computational Materials 2021年第1期7卷 846-851页

作者： Carla Lupo Evan Sheridan Edoardo Fertitta David Dubbink Chris j.Pickard Cedric Weber Theory and Simulation of Condensed Matter King’s College LondonLondonUK Happy Electron Ltd LondonUK Department of Materials Science and Metallurgy University of CambridgeCambridgeUK Advanced Institute for Materials Research Tohoku UniversitySendaiJapan

Using spin-assisted ab initio random structure searches,we explore an exhaustive quantum phase diagram of archetypal interfaced Mott insulators,***-iron and lanthanum-titanium *** particular,we report that the charge transfer induced by the interfacial electronic reconstruction stabilises a high-spin ferrous Fe2+*** provide a pathway to control the strength of correlation in this electronic state by tuning the epitaxial strain,yielding a manifold of quantum electronic phases,***-Hubbard,charge transfer and Slater insulating ***,we report that the electronic correlations are closely related to the structural oxygen octahedral rotations,whose control is able to stabilise the low-spin state of Fe2+at low pressure previously observed only under the extreme high pressure conditions in the Earth’s lower ***,we provide avenues for magnetic switching via THz radiations which have crucial implications for next generation of spintronics technologies.

关键词： Slater lanthanum quantum

A new technique for islanding operation of distribution network connected with mini hydro

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Frontiers of Information Technology & Electronic Engineering 2015年第5期16卷 418-427页

作者： j.A.LAGHARI H.MOKHLIS M.KARIMI A.H.A.BAKAR Hasmaini MOHAMAD Department of Electrical Engineering Faculty of Engineering University of Malaya Department of Electrical Engineering Quaid-e-Awam University of Engineering Science & Technology University of Malaya Power Energy Dedicated Advanced Centre (UMPEDAC) University of Malaya Faculty of Electrical Engineering University of Technology MARA (UiTM)

An islanding operation of a distribution network is a topic of interest due to the significant penetration of distributed generation(DG) in a power system network. However, controlling the frequency of an islanded distribution system remains an unresolved issue, especially when the load exceeds the generation. This paper presents a new technique for a successful islanding operation of a distribution network connected with multiple mini hydro based DGs. The proposed technique is based on three main parts. The first part uses an islanding detection technique to detect the islanding event correctly. The second part consists of a power imbalance estimation module(PIEM), which determines the power imbalance between the generation and load demand. The third part consists of a load shedding controller, which receives the power imbalance value and performs load shedding according to load priority. The proposed technique is validated on an 11 k V existing Malaysia distribution network. The simulation results show that the proposed technique is effective in performing a successful islanding operation by shedding a significant number of loads.

关键词： Islanding operation Mini hydro Distributed generation(DG) Islanding detection Load shedding

Phosphogypsum stabilization of bauxite residue:Conversion of its alkaline characteristics

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journal of Environmental Sciences 2019年第3期31卷 1-10页

作者： Shengguo Xue Meng Li jun jiang Graeme j.Millar Chuxuan Li Xiangfeng Kong School of Metallurgy and Environment Central South University Institute for Future Environments Science and Engineering Faculty Queensland University of Technology

Reduction of the high alkalinity of bauxite residue is a key problem to solve to make it suitable for plant growth and comprehensive utilization. In this study, phosphogypsum, a waste product from the phosphate fertilizer industry, was used to drive the alkaline transformation of the bauxite residue. Under optimal water washing conditions(liquid/solid ratio of 2 mL/g, 30°C, 24 hr), the impact of quantity added, reaction time and reaction mechanism during phosphogypsum application were investigated. Phosphogypsum addition effectively lowered p H levels and reduced the soluble alkalinity by 92.2%. It was found that the concentration of soluble Na and Ca ions in the supernatant increased gradually, whilst the exchangeable Na+and Ca^(2+)in solid phase changed 112 mg/kg and 259 mg/kg, respectively. Ca^(2+)became the dominant element in the solid phase(phosphogypsum addition of 2%, liquid/solid ratio of 2 mL/g, 30°C, 12 hr). X-ray diffraction data indicated that cancrinite and hydrogarnet were the primary alkaline minerals. SEM images suggested that phosphogypsum could promote the formation of stable macroaggregates, whilst the content of Ca^(2+)increased from 5.6% to 18.2% and Na reduced from 6.8% to 2.4%. Treatment with phosphogypsum could significantly promote the transformation of alkalinity cations by neutralization, precipitation and replacement *** research provided a feasible method to promote soil formation of bauxite residue by phosphogypsum amendment.

关键词： Bauxite residue Phosphogypsum Alkaline ions Alkaline transformation Soil formation

Discussion of the feasibility of air injection for enhanced oil recovery in shale oil reservoirs

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Petroleum 2017年第2期3卷 249-257页

作者： Hu jia james j.Sheng State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduSichuan610500China Bob L.Herd Department of Petroleum Engineering Texas Tech UniversityLubbockTX 79409USA

Air injection in light oil reservoirs has received considerable attention as an effective,improved oil recovery process,based primarily on the success of several projects within the Williston Basin in the United *** main mechanism of air injection is the oxidation behavior between oxygen and crude oil in the *** injection is a good option because of its wide availability and low *** air injection can be applied to shale is an interesting topic from both economic and technical *** paper initiates a comprehensive discussion on the feasibility and potential of air injection in shale oil reservoirs based on state-of-the-art literature *** and unfavorable effects of using air injection are discussed in an analogy analysis on geology,reservoir features,temperature,pressure,and petrophysical,mineral and crude oil properties of shale oil *** available data comparison of the historically successful air injection projects with typical shale oil reservoirs in the *** summarized in this *** operation methods to improve air injection performance are *** paper provides an avenue for us to make use of many of the favorable conditions of shale oil reservoirs for implementing air injection,or air huff‘n’puff injection,and the low cost of air has the potential to improve oil recovery in shale oil *** analysis may stimulate further investigation.

关键词： shale reservoirs reservoir