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modelling mechanical Properties in Native and Biomimetically Formed Vascular Grafts

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Journal of Bionic Engineering 2009年第4期6卷 371-377页

作者： m.mandru c.Ionescu m.chirita University of medicine and Pharmacy Faculty of Biomedical EngineeringUniversity street 16700115 IasiRomania Ghent University Department of Electrical energySystems and AutomationTechnologiepark 913B9052GentBelgium

The paper presents a detailed analysis of experimental data in order to characterize the elastic properties of *** analysis would provide a good basis for evaluation of biomimetic vascular *** the latter needs to exhibit similar properties of native tissue,it is important to accurately characterize the biomimetic sample in a large range of applied stresses. The stress-strain properties vary according to the specific pathology(***,aneurism)and the tissue graft must be chosen *** models are proposed in this paper on the stress-strain *** extension for frequency-domain analysis is provided for one of the *** c.m.a.ison between vascular grafts and native tissue for carotid and thoracic arteries in pigs are in good agreement with results from *** proposed experimental method offers suitable parameters for identifying models which characterize both elasticity and stiffness properties of the analyzed tissues(stress-strain).The proposed models show good performance in characterizing the intrinsic material properties.

关键词： biomimetic biomaterials vascular graft native and artificial tissues stress-strain modeling

Analysis of Differences in Productivity,Profitability and Soil Fertility Between Organic and conventional cropping Systems in the Tropics and Sub-tropics

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Journal of Integrative Agriculture 2014年第10期13卷 2299-2310页

作者： Te Pas c m Rees R m School of GeoSciences University of Edinburgh carbon management centre Scotland's Rural College

Organic farming aims to stimulate soil fertility by avoiding the use of synthetic fertiliser inputs, relying instead on locally available natural resources. It is regarded by many as a sustainable alternative to conventional fanning because it ensures higher biodiversity, restricts environmental pollution, prevents land degradation and is easy to apply for smallholder and subsistence farmers. Although widely practiced and studied in temperate regions, little is known about the potential overall benefits of organic farming in the tropics and subtropics. This paper addresses this gap by undertaking an analysis of the differences between organic and conventional agriculture in the tropics and sub-tropics based on an extensive literature review including 88 papers with 458 data pairs. The c.m.a.ison is based on three main indicators： yield, gross margin and soil organic carbon （SOc）. The differences between the organic and conventional systems for each of these main indicators is represented by the ratio of the value of the indicator in the organic system divided by the corresponding value in the conventional system. This was initially calculated for each data pair individually, and grouped by a variety of explanatory factors, such as precipitation, human development level, soil texture, crop type, organic input type, time after conversion and certification. The results demonstrate that under organic management, yields were on average 26% higher, gross margins 51% higher and soil organic carbon 53% higher than under conventional management. The highest yield increases in organic cropping systems were achieved in the least developed countries, in arid regions and on coarse soils. For gross margins, certification was the main reason for differences between organic and conventional systems. certified farmers, mostly located in developed countries, receive significantly higher prices. Furthermore, organic farming in the driest regions results in higher profits than in other

关键词： organic farming conventional fanning tropics subtropics carbon sequestration yield soil quality soil organic carbon

Role of Ag microalloying on glass forming ability and crystallization kinetics of ZrcoAgAlNi amorphous alloy

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chinese Physics B 2021年第1期30卷 471-476页

作者： A Surendar K Geetha c Rajan m Alaazim Department of Pharmacology Saveetha Dental College and HospitalSaveetha Institute of Medical and Technical SciencesChennaiIndia cSE Excel Engineering CollegePallakapalayamKomarapalayam637303India IT K S Rangasamy College of Technology TiruchengodeNamakkalTamil Nadu 637215India Faculty of Engineering Universitas Muhammadiyah Surakarta(UMS)Indonesia

Bulk metallic glasses(BmGs) with new chemical compositions(ZrcoAgAlNi) were fabricated and the effects of Ag minor addition on the glass forming ability(GFA) and crystallization kinetics were studied. The x-ray diffraction(XRD) test was applied to identify the amorphousness of BmGs or possible crystalline phases. Using differential scanning calorimeter(DSc), the thermal stability and crystallization kinetics under a non-isothermal condition at the different heating rates were studied. considering the heating rate dependency of glass transition and crystallization kinetics, the activation energy was evaluated and measured for the mentioned processes. It was revealed that the rise in Ag content led to the decrease in activation energy for glass transition, while the activation energy for crystallization increased. The thermal stability and GFA were also studied and it was found that the Ag addition strongly affected the inherent features of BmGs. With the increase in Ag content, the atomic mobility and structural rearrangement changed in the material and consequently, the GFA and thermal stability were significantly improved.

关键词： bulk metallic glass materials design crystallization kinetics glass forming ability

combining material characterization with single and multi-oxyanion adsorption for mechanistic study of chromate removal by cationic hydrogel

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Journal of Environmental Sciences 2011年第6期23卷 1004-1010页

作者： Irene m.c.Lo Samuel c.N.Tang Department of civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong KongChina

cationic hydrogel with magnetic property was synthesized via radical polymerization and its removal capacity of chromate from contaminated water was found to be 200 mg/*** Fourier transform infrared spectroscopy（FT-IR） study,the mechanism of chromate removal by hydrogel was found to be non-specific adsorption,mainly due to ion exchange,as evidenced by the positively charged functional group,trimethyl ammonium-N＋（cH3）3,in the *** were accordingly determined by testing di？erent oxyanion adsorption onto the *** results of the chromate adsorption experiments illustrated that the amount of chromate adsorbed was nearly equal to that of the chloride released from the hydrogel,which is part of the evidence for ion *** and multi-oxyanion adsorption experiments were also performed,and it was demonstrated that ion removal was species independent,but charge dependent,another characteristic of the ion exchange *** was found that the same Langmuir model can be applied to best fit the findings of single and multi-oxyanion adsorption,which further indicates the mechanism of chromate removal is attributed to ion *** view of the above,the background anions compete for adsorption sites with chromate,evidenced by inhibitive chromate removal in the presence of background electrolytes in the batch studies,further echoing the ion exchange mechanism.

关键词： adsorption magnetic hydrogel mechanism ion exchange oxyanion

Preliminary performance analysis and optimization based on 1D neutronics model for Indian DEmO HccB blanket

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Plasma Science and Technology 2020年第8期22卷 184-191页

作者： D AGGARWAL c DANANI m Z YOUSSEF Institute for Plasma Research GandhinagarGujarat 382428India Homi Bhabha National Institute(HBNI) AnushaktinagarMumbai 400094India University of california-Los Angeles Los AngelesCA 90095United States of America

India,under its breeding blanket R&D program for DEmO,is focusing on the development of two tritium breeding blanket concepts;namely the lead-lithium-cooled ceramic breeder and the helium-cooled ceramic breeder(HccB).The study presented in this paper focuses on the neutronic design analysis and optimization from the tritium breeding perspective of the HccB *** Indian concept has an edge-on configuration and is one of the variants of the helium-cooled solid breeder blanket concepts proposed by several partner countries in *** Indian HccB blanket having lithium titanate(Li2TiO3)as the tritium breeder and beryllium(Be)as the neutron multiplier with reduced-activation ferritic/martensitic steel structure aims at utilizing the low-energy neutrons at the rear part of the *** aim of the optimization study is to minimize the radial blanket thickness while ensuring tritium self-sufficiency and provide data for further neutronic design and thermal-hydraulic layout of the HccB *** is found that inboard and outboard blanket thicknesses of 40 cm and 60 cm,respectively,can give a tritium breeding ratio(TBR)>1.3,with 60%6Li enrichment,which is assumed to be sufficient to cover potential tritium losses and associated *** results also demonstrated that the Be packing fraction(PF)has a more profound impact on the TBR as c.m.a.ed to 6Li enrichment and the PF of Li2TiO3.

关键词： DEmO helium-cooled ceramic breeder blanket neutronic optimization study tritium breeding ratio

Interplay of parallel electric field and trapped electrons in kappa-maxwellian auroral plasma for EmEc instability

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communications in Theoretical Physics 2021年第1期73卷 78-86页

作者： m Nazeer m N S Qureshi c Shen Department of Physics GC UniversityLahore(54000)Pakistan Shenzhen Graduate School HIT CampusUniversity Town of ShenzhenShenzhen 518055China

In this paper,propagation characteristics of electromagnetic electron cyclotron(EmEc)waves based on kappa-maxwellian distribution have been investigated to invoke the interplay of the electric field parallel to the Earth’s magnetic field and auroral trapped *** dispersion relation for EmEc waves in kappa-maxwellian distributed plasma has been derived using the contribution of the parallel electric field and trapped electron *** results show that the presence of the electric field has a stimulating effect on growth rate,which is more pronounced at low values of wave *** is also observed that as the threshold value of trapped electron speed is surpassed,it dominates the effect of the parallel electric field and EmEc instability is enhanced *** electric field acts as another source of free energy,and growth can be obtained even in the absence of trapped electron drift speed and for very small values of temperature *** the present study reveals the interplay of the parallel electric field and trapped electron speed on the excitation of EmEc waves in the auroral region.

关键词： EmEc waves kappa-maxwellian distribution trapped electrons parallel electric field in aurora

TRANSIENT ANALYSIS OF cOmPOSITE PLATES BY A LOcAL RADIAL BASIS FUNcTIONS-FINITE DIFFERENcE TEcHIQUE

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Acta mechanica Solida Sinica 2012年第1期25卷 22-36页

作者： c.m.c.Roque D.cunha A.J.m.Ferreira INEGI Faculdade de Engenharia da Universidade do PortoRua Dr.Roberto Frias Departamento de Engenharia mecnica Faculdade de Engenharia da Universidade do PortoRua Dr.Roberto Frias

The use of local numerical schemes,such as finite differences produces much better conditioned matrices than global collocation radial basis functions ***,finite differ-ence schemes are limited to special *** scattered points,a combination of finite differences and radial basis functions would be a possible *** this paper,we use a higher-order shear deformation plate theory and a radial basis function-finite difference technique for predicting the transient behavior of thin and thick composite *** numerical experiments on beams and composite plates,the accuracy and efficiency of this collocation technique is demonstrated.

关键词： meshless beam composite plate

A Dimension-Reduction Interval Analysis method for Uncertain Problems

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computer modeling in Engineering & Sciences 2017年第3期113卷 239-259页

作者： J.c.Tang c.m.Fu State Key Laboratory of Advanced Design and manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha City410082P.R.China college of mechanical Engineering University of South ChinaHengyang 421001P.R.China

In this paper,an efficient interval analysis method called dimension-reduction interval analysis(DRIA)method is proposed to calculate the bounds of response functions with interval variables,which provides a kind of solution method for uncertainty analysis problems of complex structures and ***,multi-dimensional function is transformed into multiple one-dimensional functions by extending dimension reduction method to the interval analysis ***,all the one-dimensional functions are transformed to standard quadratic form by second order Taylor expansion *** a result,the multi-dimensional function is approximately represented by the functions that each interval variable occurs once,and interval power arithmetic can be used to efficiently calculate the bounds of response functions in restricted ***,three numerical examples and an engineering application are investigated to demonstrate the validity of the proposed method.

关键词： Interval uncertainty interval analysis dimension-reduction method over estimation

Heavy metals and PAHs in Sewage Sludge from Twelve Wastewater Treatment Plants in Zhejiang Province

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Biomedical and Environmental Sciences 2008年第4期21卷 345-352页

作者： c. m. TIENTcHEN college of Environmental and Resource Sciences Zhejiang University

Objective To investigate the heavy metals （Hms） and polycyclic aromatic hydrocarbons （PAHs） in sludge of twelve wastewater treatment plants （WWTPs） in Zhejiang province of china, and to assess their potential for land application. methods Sludge was collected from 12 WWTPs within the province. Gc-mS and AAS were used to measure PAHs and Hms contents in sludge. Results concentrations of Hms in most of the sludge samples were below the regulatory limits for the sludge to be used in agriculture in china with the exception of Zn in 2 sludge samples and cd in 1 sample. All 16 PAHs, targeted by the USEPA agency, were found in the sludge from the twelve plants with a total concentration ranging from 33.73 mg kg^-1 to 82.58 mg kg^-1 （dry weight, d.w.）. The levels of Σ9 PAHs varied from 13.87 mg kg^-1 to 61.86 mg kg^-1 （d.w.） in the sludge, far exceeding the limitation value recommended by the Europe Union. The concentration and composition of PAHs in sewage sludge varied and depended mainly on the quantity and type of industrial wastewater accepted by the WWTPs. A significant relationship between the proportion of industrial wastewater received by WWTPs and the total content of 16 PAHs in the sludge was observed. conclusion PAHs have become one of the primary pollutants in sludge of Zhejiang WWTPs instead of Hms. It is, therefore, essential to reduce the contents of PAHs before the sludge can be used in agriculture through proper treatment.

关键词： Sludge Heavy metal chemical Fractions Polycyclic aromatic hydrocarbons contribution