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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

Hydrogeochemical evaluation and statistical analysis of groundwater of Sylhet, north-eastern Bangladesh

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Acta Geochimica 2019年第3期38卷 440-455页

作者： Nasir Ahmed Md.Bodrud-Doza S.M.Didar-Ul Islam Manzoor Ahmad Choudhry Md.Iftakharul Muhib Anwar Zahid Shahadat Hossain Md.Moniruzzaman Nipa Deb Md.Abdul Quaiyum Bhuiyan isotope Hydrology division Institute of Nuclear Science and Technology Atomic Energy Research Establishment Department of Environmental Sciences Jahangirnagar University isotope Hydrology Section Department of Nuclear Sciences and Applications International Atomic Energy Agency Groundwater Hydrology Bangladesh Water Development Board

To investigate the hydrogeochemical characteristics of groundwater 23 shallow, 30 intermediate and 38 deep wells samples were collected from Sylhet district of Bangladesh, and analyzed for temperature, pH, Eh, EC,DO, DOC, Na^+, K^+, Ca^(2+), Mg^(2+), Cl^-, SO_4^(2-), NO_3^-,HCO_3^-, SiO_2^-, Fe, Mn and As. Besides, 12 surface water samples from Surma and Kushiyara Rivers were also collected and analyzed to understand the influence into aquifers. Results revealed that, most of the groundwater samples are acidic in nature, and Na–HCO_3 is the dominant groundwater type. The mean value of temperature, EC,Na^+, K^+, Ca^(2+), Mg^(2+), Cl^-, NO_3^- and SO_4^(2-) were found within the range of permissible limits, while most of the samples exceeds the allowable limits of Fe, Mn and As concentrations. However, relatively higher concentration of Fe and Mn were found in deep water samples and reverse trend was found in case of As. The mean concentrations of As in shallow, intermediate and deep wells were 39.3, 25.3and 21.4 lg/L respectively, which varied from 0.03 to148 lg/L. From spatial distribution, it was found that Fe,Mn and As concentrations are high but patchy in northern,north-western, and south-western part of Sylhet region. The most influential geochemical process in study area were identified as silicate weathering, characterized by active cation exchange process and carbonate weathering, which thereby can enhance the elemental concentrations in groundwater. Pearson's correlation matrix, principal component analysis and cluster analysis were also employed to evaluate the controlling factors, and it was found that, both natural and anthropogenic sources were influencing the groundwater chemistry of the aquifers. However, surface water has no significant role to contaminate the aquifers,rather geogenic factors affecting the trace elemental contamination. Thus it is expected that, outcomes of this study will provide useful insights for future groundwater monitoring and

关键词： Arsenic Groundwater Hydrogeochemistry Multivariate statistics Spatial distribution

INTEGRATED VEGETATION CLASSIFICATION AND MAPPINGUSING REMOTE SENSING AND GIS TECHNIQUES

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Chinese Geographical Science 1999年第1期9卷 49-56页

作者：庄大方凌扬荣 Institute of Remote Sensing applications the Chinese Academy of Sciences Beijing P. R. China Forest and Forestry production Research Institute Japan

NOAA-AVHRR data have been more and more used by scientists because of its short temporal resolution,large scope, inexpensive cost and broad wave bands. On macro and middle scale of vegetation remote sensing, NOAAAVHRR possesses an advantage when compared with other satellites. However, because NOAA-AVHRR also problem of low resolution, data distortion and geometrical distortion, in the area of application of NOAA-AVHRR in largescale vegetation - mapping, the accuracy of vegetation classification should be improved. This paper discuss the feasibilityof integrating the geographic data in GIS(Geographical Information System) and remotely sensed data in GIS. Under theenvironment of GIS, temperature, precipitation and elevation, which serve as main factors affecting vegetation growth,were processed by a mathematical model and qualified into geographic image under a certain grid system. The geographicimage were overlaid to the NOAA-AVHRR data which had been compressed and processed. In order to evaluate the usefulness of geographic data for vegetation classification, the area under study was digitally classified by two groups of interpreter: the proposed methodology using maximum likelihood classification assisted by the geographic database and a conventional maximum likelihood classification only. Both result were compared using Kappa statistics. The indices to both theproposed and the conventional digital classification methodology were 0. 668(yew good) and 0. 563(good), *** geographic database rendered an improvement over the conventional digital classification. Furthermore, in this study,some problems related to multi-sources data integration are also discussed.

关键词： NOAA-AVHRR NDVI(Normal division Vegetation Index) geographic image integrated image remote sensing supervised classification GIS

Decoupling of Currents in Travelling Wave Induction Heating

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Journal of Electromagnetic Analysis and applications 2014年第7期6卷 193-202页

作者： Kenneth Frogner Tord Cedell Mats Andersson division of production and Materials Engineering Lund University Lund Sweden

Travelling wave induction heating (TWIH) suffers from severe interference between the coils, which significantly reduces its efficiency. A strategy for decoupling the currents in TWIH is presented, based on the anti-series or anti-parallel connection of several inductors. The study investigates the coupling effect in terms of amplitude and phase shift as functions of current and frequency, respectively, including resonance behavior. In addition, the effects of deviations of the inductor properties are analyzed. Measurements indicate that the strategy produces very good results, almost eliminating the coupling effect, increasing the efficiency, and simplifying control. Simulated and measured results of the heating pattern are compared and efficiency values and power densities are presented.

关键词： Induction Heating Inductive Coupling Decoupling Travelling Wave Uniform Heating

Investigation of Thermal Losses in a Soft Magnetic Composite Using Multiphysics Modelling and Coupled Material Properties in an Induction Heating Cell

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Journal of Electromagnetic Analysis and applications 2016年第9期8卷 182-196页

作者： Leif Siesing Kenneth Frogner Tord Cedell Mats Andersson division of production and Materials Engineering Lund University Lund Sweden

The complex interaction between material properties in an induction heating circuit was studied by multi physics simulation and by experimental verification in a full-scale laboratory heater. The work aims to illustrate the complexity of the system of interacting materials, but also to propose a method to verify properties of soft magnetic composite materials in an integrated system and to identify which properties are the most critical under different circumstances and load cases. Heat losses at different loads were primarily studied, from DC currents to AC currents at 15, 20 and 25 kHz, respectively. A FE model for magnetic simulation was correlated with a corresponding model for heat simulation. The numerical model, as well as the established input material data, could be verified through the experimental measurements. In this particular study, the current loss in the litz wire was the dominant heat source, thus making the thermal conductivity of the SMC the most important property in this material.

关键词： Soft Magnetic Moldable Composite Multiphysics Litz Induction Heating Thermal Losses Coupled Material Properties

Analytical and computational modelling for wave energy systems：the example of oscillating wave surge converters

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Acta Mechanica Sinica 2017年第4期33卷 647-662页

作者： Frédéric Dias Emiliano Renzi Sarah Gallagher Dripta Sarkar Yanji Wei Thomas Abadie Cathal Cummins Ashkan Rafiee School of Mathematics and Statistics University College Dublin MaREI Centre Belfield Dublin 4 Ireland Department of Mathematical Sciences Loughborough University Leicestershire LE11 3TU UK Research Environment and Applications Division Met Eireann Glasnevin Dublin 9 Ireland Department of Engineering Sciences University of OxfordOxford UK Advanced production Engineering University of GroningenGroningen The Netherlands Dublin City University Glasnevin Dublin 9 Ireland School of Engineering University of Edinburgh EdinburghUK Carnegie Clean Energy Limited Northam Australia

The development of new wave energy converters has shed light on a number of unanswered questions in fluid mechanics, but has also identified a number of new issues of importance for their future deployment. The main concerns relevant to the practical use of wave energy converters are sustainability, survivability, and maintainability. Of course,it is also necessary to maximize the capture per unit area of the structure as well as to minimize the cost. In this review, we consider some of the questions related to the topics of sustainability, survivability, and maintenance access, with respect to sea conditions, for generic wave energy converters with an emphasis on the oscillating wave surge converter. New analytical models that have been developed are a topic of particular discussion. It is also shown how existing numerical models have been pushed to their limits to provide answers to open questions relating to the operation and characteristics of wave energy converters.

关键词： surge oscillating survivability ocean maintenance modelling capture deployment maximize converter

Ultrasonic tomography and its applications in oilfield

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第12期6卷 1420-1423页

作者：钟兴福吴应湘李东晖李强王兴国 Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China China Petroleum Logging Co. Ltd. Changqing Business division Changqing 710021 China Daqing production Well Logging Institute Daqing 163453 China

UTT （Ultrasonic Tomography Tool） is widely used in the oil industry and can be used to inspect corrosion, casing wall damage, casing breakoff, and casing distortion in the well borehole with the maximum environment temperature being 125 ℃, and the pressure being 60 MPa. UTT consists of tool head, upper centralization, electronic section, lower centralization, transmitters, and receivers. Its outer diameter is 4.6 cm and length is 320 cm. The measured casing diameter ranges from 60 mm to 254 mm. The tomography resolution is 512×512. The borehole measurement accuracy is 2 mm. It can supply 3D pipe tomography, including horizontal and vertical profile. This paper introduces its specification, measurement principle, and applications in oilfield.

关键词： Ultrasonic tomography Downhole tool Casing hole

Prospecting microbial biofilms as climate smart strategies for improving plant and soil health: A review

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Pedosphere 2023年第1期33卷 129-152页

作者： Kulandaivelu VELMOUROUGANE Shobit THAPA Radha PRASANNA division of Crop production Indian Council of Agricultural Research-Central Institute for Cotton Research(CICR)Nagpur 440010India Indian Council of Agricultural Research-National Bureau of Agriculturally Important Microorganisms KushmaurMau Nath Bhanjan 275103India division of Microbiology Indian Council of Agricultural Research-Indian Agricultural Research InstituteNew Delhi 110012India

Microbes and their products play key roles in complementing chemical fertilizers and plant protection chemicals by eliciting defence mechanisms in crop plants,thereby providing immunity and resistance against diverse *** the different environmental technologies used to mitigate climate change,several microbiological interventions are promising,among which biofilms,both naturally-existing and laboratory-developed,and their application have gained momentum *** biofilms are aggregations of microbial cells in a self-generated polymeric matrix,which are produced by several genera of bacteria,yeasts,cyanobacteria,and fungi as a mode of reproductive fitness,thereby advantageous in successful proliferation,even in extreme *** propensity of microbial biofilms to grow in diverse niches and adapt to biotic and abiotic stresses illustrates their immense potential as biofertilizers and disease suppression options in various crops across diverse *** the inhospitable habitats of deserts and denudated land,biofilms play an important role in preventing soil erosion and sustaining vegetation,microflora,and *** represent a mode of growth for several microbes with plant growth-promoting and biocontrol potential,which are important in seed establishment and the facilitation of exchanging nutrients and metabolites from the *** this review,we discuss the prospects of microbial biofilms as a green option in agriculture in general and,more specifically,their potential in mitigating climate change.

关键词： biocontrol bioremediation climate change environmental stress nutrient sequestration plant growth promotion

Study on spatial pattern of land-use change in China during 1995—2000

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Science China Earth Sciences 2003年第4期46卷 373-384页

作者：刘纪远刘明亮庄大方张增祥邓祥征 Institute of Geographic Sciences of Natural Resources Research Chinese Academy of Sciences Institute of Remote Sensing applications Chinese Academy of Sciences

It is more and more acknowledged that land-use/cover dynamic change has become a key subject urgently to be dealt with in the study of global environmental change. Supported by the Landsat TM digital images, spatial patterns and temporal variation of land-use change during 1995—2000 are studied in the paper. According to the land-use dynamic degree model, supported by the 1km GRID data of land-use change and the comprehensive characters of physical, economic and social features, a dynamic regionalization of land-use change is designed to disclose the spa-tial pattern of land-use change processes. Generally speaking, in the traditional agricultural zones, e.g., Huang-Huai-Hai Plains, Yangtze River Delta and Sichuan Basin, the built-up and residential areas occupy a great proportion of arable land, and in the interlock area of farming and pasturing of northern China and the oases agricultural zones, the reclamation of arable land is conspicuously driven by changes of production conditions, economic benefits and climatic conditions. The im-plementation of returning arable land into woodland or grassland policies has won initial success in some areas, but it is too early to say that the trend of deforestation has been effectively reversed across China. In this paper, the division of dynamic regionalization of land-use change is designed, for the sake of revealing the temporal and spatial features of land-use change and laying the foundation for the study of regional scale land-use changes. Moreover, an integrated study, in-cluding studies of spatial pattern and temporal process of land-use change, is carried out in this paper, which is an interesting try on the comparative studies of spatial pattern on change process and the change process of spatial pattern of land-use change.

关键词： land-use change China spatial pattern regionalization. Land

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

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Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon C.Daeschler Katelyn J.W.So Konstantin Feinberg Marina Manoraj Jenny Cheung Jennifer Zhang Kaveh Mirmoeini JPaul Santerre Tessa Gordon Gregory HBorschel SickKids Research Institute Neuroscience and Mental Health ProgramTorontoONCanada Institute of Biomaterials and Biomedical Engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and Engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong ***,there are no FDA-approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve *** authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug *** is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible *** released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegradable local drug delivery nerve injury nerve regeneration nerve wrap tacrolimus