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Insect Science 2011年第5期18卷 583-589页

作者： m. j. Lopez-Rodriguez j. m. Tierno de Figueroa j. Alba-Tercedor Departamento de Biologia Animal Facultad de Ciencias Universidad de Granada Granada Spain

The nymphal biology of a population of Torleya major （Klapalek） in southem Iberian Peninsula was studied. An atypical life cycle pattern is described, with eggs hatching in August producing a fast-developing cohort with adults emerging in autumn and a second slow-developing cohort with adults emerging in spring of the following year. Nymphal growth occurred primarily in summer-autumn （in the first cohort） and in spring （in the second）. The origin of such a life history is discussed. Nymphs were collector-gatherers, consuming mainly detritus. Although ontogenetic shifts on the use of trophic resources were detected, similar food was utilized during the months when both cohorts cohabited, eliminating the possibility that the rapid growth of the first cohort could be related to the utilization of different food resources.

关键词： collector-gatherer life cycle mayfly nymphal feeding southern Iberian Peninsula

Distributed DC-Bus Signaling Control of Photovoltaic Systems in Islanded DC microgrid

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CSEE journal of Power and Energy Systems 2022年第6期8卷 1741-1750页

作者： Noushin Poursafar m.j.Hossain Seyedfoad Taghizadeh macquarie University SydneyNew South WalesAustralia

The stability of an islanded DC microgrid(DCmG)is highly dependent on the presence and performance of the backup energy storage system(BESS),due to the lack of main grid *** condition makes the DCmG vulnerable to the critical situation of absence of the BESS,which could be caused by a fault or being fully charged or *** paper presents an enhanced distributed DC-bus signaling control strategy for converters of photovoltaic systems(PVs)to make the islanded DCmG less dependent on the *** a conventional control approach that utilizes PVs to operate in maximum power point tracking(mPPT)mode and the BESS solely regulating DC-bus voltage,the proposed control method maintains DC-bus voltage via intelligently managing output powers of the *** proposed control method continuously monitors DC-bus voltage and regulates the output powers of all the PVs via switching between mPPT mode and voltage regulating ***,if the DC-bus voltage level is less than a predefined maximum level,the PVs work in mPPT mode;otherwise,the PVs work in voltage regulating mode to maintain DC-bus voltage at an acceptable *** switching between mPPT and voltage regulating control operations results in protecting the DCmG from unavoidable shutdowns conventionally necessary during the absence of the BESS ***,the proposed control method reduces oscillations on the DC-bus voltage during existence of the *** performance and effectiveness of the proposed control strategy are validated through different case studies in mATLAB/Simulink.

关键词： DC microgrid voltage stability islanding mode distributed control distributed generator(DG)

Thermal analysis in swirl motion of maxwell nanofluid over a rotating circular cylinder

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Applied mathematics and mechanics(English Edition) 2020年第9期41卷 1417-1430页

作者： A.AHmED m.KHAN j.AHmED Department of mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

In this paper,the mechanism of thermal energy transport in swirling flow of the maxwell nanofluid induced by a stretchable rotating cylinder is *** rotation of the cylinder is kept constant in order to avoid the induced axially secondary ***,the novel features of heat generation/absorption,thermal radiation,and joule heating are studied to control the rate of heat *** effects of Brownian and thermophoretic forces exerted by the maxwell nanofluid to the transport of thermal energy are investigated by utilizing an effective model for the nanofluid proposed by *** whole physical problem of fluid flow and thermal energy transport is modelled in the form of partial differential equations(PDEs)and transformed into nonlinear ordinary differential equations(ODEs)with the help of the suitable flow *** acquired results through the technique bvp4c are reported graphically with physical *** analysis reveals that there is higher transport of heat energy in the maxwell nanoliquid for a constant wall temperature(CWT)as compared with the prescribed surface temperature(PST).Both thermophoretic and Brownian forces enhance the thermal energy transport in the flowing maxwell ***,the temperature distribution increases with increasing values of the radiation parameter and the Eckert *** is also noted that an increase in Reynolds number reduces the penetration depth,and as a result the flow and transport of energy occur only near the surface of the cylinder.

关键词： maxwell nanofluid rotating cylinder heat source/sink joule heating convective condition numerical solution

Effect of periodic heat transfer on the transient thermal behavior of a convective-radiative fully wet porous moving trapezoidal fin

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Applied mathematics and mechanics(English Edition) 2023年第4期44卷 653-668页

作者： B.j.GIREESHA m.L.KEERTHI Department of PG Studies and Research in mathematics Kuvempu UniversityShankaraghatta 577451India

A moving trapezoidal profiled convective-radiative porous longitudinal fin wetted in a single-phase fluid is considered in the current *** periodic variation in the fin base temperature is taken into account along with the temperature sensitive thermal conductivity and convective heat transfer *** modeled problem,which is resolved into a non-linear partial differential equation(PDE),is made dimensionless and solved by employing the finite difference method(FDm).The results are displayed through graphs and *** effects of amplitude,frequency of oscillation,wet nature,Peclet number,and other relevant quantities on the distribution of temperature through the fin length and with the dimensionless time are *** is deciphered that the periodic heat transfer gives rise to the wavy nature of the fin thermal profile against *** analysis is beneficial in the design of fin structures for applications like solar collectors,space/airborne applications,and refrigeration industries.

关键词： convection fully wet porous fin trapezoidal profile moving fin unsteady periodic thermal condition

Transport model for shale gas well leakage through the surrounding fractured zones of a longwall mine

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International journal of mining Science and Technology 2020年第5期30卷 635-641页

作者： Kayode m.Ajayi Steven j.Schatzel Centers for Disease Control and Prevention National Institute for Occupational Safety and HealthPittsburghPA 15236USA

The environmental risks associated with casing deformation in unconventional(shale)gas wells positioned in abutment pillars of longwall mines is a concern to many in the mining and gas well *** the recent interest in shale exploration and the proximity to longwall mining in Southwestern Pennsylvania,the risk to mine workers could be catastrophic as fractures in surrounding strata create pathways for transport of leaked ***,this research by the National Institute for Occupational Safety and Health(NIOSH)presents an analytical model of the gas transport through fractures in a low permeable *** derived equations are used to conduct parametric studies of specific transport conditions to understand the influence of stratum geology,fracture lengths,and the leaked gas properties on subsurface *** results indicated that the prediction that the subsurface gas flux decreases with an increase in fracture length is specifically for a non-gassy *** sub-transport trend could be significantly impacted by the stratum gas generation rate within specific fracture lengths,which emphasized the importance of the stratum *** findings provide new insights for improved understanding of subsurface gas transport to ensure mine safety.

关键词： Subsurface gas transport Longwall mining Shale gas well Analytical modeling Environmental risk Shale gas casing failure

Potential Contribution of Combined Atmospheric Ca^(2+) and mg^(2+) Wet Deposition Within the Continental U.S. to Soil Inorganic Carbon Sequestration

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Pedosphere 2013年第6期23卷 808-814页

作者： E.A.mIKHAILOVA m.A.GODDARD C.j.POST m.A.SCHLAUTmAN j.m.GALBRAITH School of Agricultural Forestand Environmental SciencesClemson University Department of Environmental Engineering and Earth Sciences Clemson University Department of Crop and Soil Environmental Sciences Virginia Tech

Soil inorganic carbon （SIC） stocks continuously change from the formation of pedogenic carbonates, a process requiring inputs of Ca2＋ and mg2＋ ions. This study ranked the soil orders in terms of potential inorganic carbon sequestration resulting from wet Ca2＋ and mg2＋ deposition from 1994 to 2003 within the continental United States. The analysis revealed that average annual atmospheric wet deposition of Ca2＋ and mg2＋ was the highest in the Central midwest-Great Plains region, likely due to soil particle input from loess-derived soils. The soil orders receiving the highest total average annual atmospheric wet Ca2＋ and mg2＋ deposition, expressed as potential inorganic carbon formation （barring losses from erosion and leaching）, were： 1） mollisols （1.1 × 10^8 kg C）, 2） Alfisols （8.4 × 10^7 kg C）, 3） Entisols （3.8 × 10^7 kg C）, and 4） Aridisols （2.8 × 10^7 kg C）. In terms of area-normalized result, the soil orders were ranked： 1） Histosols （73 kg C km-2）, 2） Alfisols and Vertisols （64 kg C km-2）, 3） mollisols （62 kg C km-2）, and 4） Spodosols （52 kg C kin-2）. The results of this study provide an estimate of potential soil inorganic carbon sequestration as a result of atmospheric wet Ca2＋ and mg2＋ deposition, and this information may be useful in assessing dynamic nature of soil inorganic carbon pools.

关键词： calcite carbon cycle dolomite pedogenic

Nanoparticles for targeted cancer radiotherapy

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Nano Research 2020年第11期13卷 2887-2897页

作者： Roger m.Pallares Rebecca j.Abergel Chemical Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA94720USA Department of Nuclear Engineering University of CaliforniaBerkeleyCA94720USA

Radiotherapy,where ionizing radiation is locally delivered either through an external beam or by surgically implanting radionuclide-based seeds in the tumor,is one of the gold standard treatments for *** to the non-selective nature of radiation,healthy tissue surrounding the cancerous region is usually affected by the ***,new strategies,including targeted alpha therapy,are being studied to improve the selectivity of the treatment and minimize side *** challenges,however,limit the current development of targeted radiotherapy,such as the functionalization of the therapeutic agent with targeting vectors and controlling the release of recoiling *** offer unique opportunities as drug delivery vehicles,since they are biocompatible,enhance the cellular uptake of drugs,and are easily functionalized with targeting *** this review,we examine how nanoparticles can be used for targeted radiotherapy,either as sensitizers of external beams or as delivery vehicles for therapeutic *** describe the clinical relevance of different types of nanoparticles,followed by an analysis of how these nanoconstructs can solve some of the main limitations of conventional ***,we critically discuss the current situation of nanoparticle-based radiotherapy in clinical settings and challenges that need to be overcome in the future for further development of the field.

关键词： radiotherapy targeted cancer radiotherapy nanoparticles cancer targeted alpha therapy external beam

Homogeneous Plastic Flow of Fully Amorphous and Partially Crystallized Zr_(41.2)Ti_(13.8)Cu_(12.5)Ni_(10)Be_(22.5) Bulk metallic Glass

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journal of materials Science & Technology 2003年第6期19卷 557-560页

作者： Q.WANG j.j.Blandin m.Suery B.Van de moortele j.m.Pelletier GPm2 ENSPG D.U. B.P.46 38042 Grenoble France Institute of Materials Shanghai University Shanghai 200072 ChinaGPM2 ENSPG D.U. B.P.46 38042 Grenoble FranceGPM2 ENSPG D.U. B.P.46 38042 Grenoble FranceGEMPPM Bat. B. PascalINSA 69621 Villeurbanne Cedex FranceGEMPPM Bat. B. PascalINSA 69621 Villeurbanne Cedex France

The homogeneous plastic flow of fully amorphous and partially crystallized Zr(41.2)Ti(13.8)Cu(12.5)Ni(10)Be(22.5) bulk metallic glass (Vitl) has been investigated by compression tests at high temperatures in supercooled liquid region. Experimental results show that at sufficiently low strain rates, the supercooled liquid of the fully amorphous alloy reveals Newtonian flow with a linear relationship between the flow stress and strain rate. As the strain rate is increased, a transition from linear Newtonian to nonlinear flow is detected, which can be explained by the transition state theory. Over the entire strain rate interval investigated, however, only nonlinear flow is present in the partially crystallized alloy, and the flow stress for each strain rate is much higher. It is found that the strain rate-stress relationship for the partially crystaltized alloy at the given temperature of 646 K also obeys the sinh law derived from the transition state theory, similar to that of the initial homogeneous amorphous alloy. Thus, it is proposed that the flow behavior of the nanocrystalline/amorphous composite at 646 K is mainly controlled by the viscous flow of the remaining supercooled liquid.

关键词： Homogeneous plastic flow Zr41.2Ti13.8Cu12.5Ni10Be22.5 amorphous alloy,Partially crystallized amorphous alloy

Transient flow of magnetized maxwell nanofluid: Buongiorno model perspective of Cattaneo-Christov theory

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Applied mathematics and mechanics(English Edition) 2020年第4期41卷 655-666页

作者： m.KHAN A.AHmED j.AHmED Department of mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

The present research article is devoted to studying the characteristics of Cattaneo-Christov heat and mass fluxes in the maxwell nanofluid flow caused by a stretching sheet with the magnetic field *** maxwell nanofluid is investigated with the impact of the Lorentz force to examine the consequence of a magnetic field on the flow characteristics and the transport of *** heat and mass transport mechanisms in the current physical model are analyzed with the modified versions of Fourier’s and Fick’s laws,***,the well-known Buongiorno model for the nanofluids is first introduced together with the Cattaneo-Christov heat and mass fluxes during the transient motion of the maxwell *** governing partial differential equations(PDEs)for the flow and energy transport phenomena are obtained by using the maxwell model and the Cattaneo-Christov theory in addition to the laws of *** transformations are used to convert the PDEs into a system of nonlinear ordinary differential equations(ODEs).The homotopic solution methodology is applied to the nonlinear differential system for an analytic *** results for the time relaxation parameter in the flow,thermal energy,and mass transport equations are discussed *** is noted that higher values of the thermal and solutal relaxation time parameters in the Cattaneo-Christov heat and mass fluxes decline the thermal and concentration fields of the ***,larger values of the thermophoretic force enhance the heat and mass transport in the ***,the Brownian motion of the nanoparticles declines the concentration field and increases the temperature *** validation of the results is assured with the help of numerical tabular data for the surface velocity gradient.

关键词： transient flow Cattaneo-Christov theory maxwell nanofluid Buongiorno model homotopy analysis method (HAm) solution

Boundary layer flow of maxwell fluid due to torsional motion of cylinder: modeling and simulation

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Applied mathematics and mechanics(English Edition) 2020年第4期41卷 667-680页

作者： m.KHAN A.AHmED j.AHmED Department of mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

This paper investigates the boundary layer flow of the maxwell fluid around a stretchable horizontal rotating cylinder under the influence of a transverse magnetic *** constitutive flow equations for the current physical problem are modeled and analyzed for the first time in the *** torsional motion of the cylinder is considered with the constant azimuthal velocity *** partial differential equations(PDEs)governing the torsional motion of the maxwell fluid together with energy transport are simplified with the boundary layer *** current analysis is valid only for a certain range of the positive Reynolds ***,for very large Reynolds numbers,the flow becomes ***,the governing similarity equations are simplified through suitable transformations for the analysis of the large Reynolds *** numerical simulations for the flow,heat,and mass transport phenomena are carried out in view of the bvp4c scheme in *** outcomes reveal that the velocity decays exponentially faster and reduces for higher values of the Reynolds numbers and the flow penetrates shallower into the free stream *** is also noted that the phenomenon of stress relaxation,described by the Deborah number,causes to decline the flow fields and enhance the thermal and solutal energy transport during the fluid *** penetration depth decreases for the transport of heat and mass in the fluid with the higher Reynolds *** excellent validation of the numerical results is assured through tabular data with the existing literature.

关键词： torsional motion maxwell fluid magnetic field stretchable rotating cylinder bvp4c scheme