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Propulsion and Power Research 2019年第3期8卷 234-242页

作者： m.i.Afridi m.Qasim Department of mathematics COMSATS Institute of Information TechnologyIslamabad45550Pakistan

in the present article,we perform the second law analysis of classical Blasius flow accounting the effects of nonlinear radiation and frictional *** two-dimensional boundary layer momentum and energy equations are converted to self-similar equations using similarity *** set of resultant ordinary differential equations are solved *** numerical results obtained from solutions of dimensionless momentum and energy equations are used to calculate the entropy generation number and Bejan *** velocity profile f'(ξ),temperature distributionθ(ξ),entropy production number Ns and Bejan number Be are plotted against the physical flow parameters and are discussed in ***,for the sake of validation of our numerical code,the obtained results are reproduced using matlab built-in boundary value solver bvp4c resulting in an excellent *** is observed that entropy generation is increasing function of heating parameter,Prandtl number,Eckert number and radiation ***,it is observed that entropy generation can be minimized by reducing the operating temperatureΔT=T_(w)−T_(∞).

关键词： Second law analysis Boundary layer Nonlinear Rosseland thermal radiation Energy dissipation bvp4c

An ultraviolet to visible scheme to estimate chromophoric dissolved organic matter absorption in a Case-2 water from remote sensing reflectance

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Frontiers of Earth Science 2020年第2期14卷 384-400页

作者： Xia LEi Jiayi PAN adam DEVLiN institute of Space and Earth information Science The Chinese University of Hong KongHong KongChina School of Geography and Environment Jiangxi Normal UniversityNanchang 330022China

in a typical Case-2 coastal water environment(here,the Pearl River Estuary(PRE),China),chromophoric dissolved organic matter(CDOm)and suspended particulates dominate the water optical properties,and CDOm fluorescence contributes considerably to surface water *** this paper,an ultraviolet(UV)to visible scheme to retrieve CDOm absorption(ag)is developed based on a set of in situ ***,the CDOm UV absorption and spectral slope(Sg)are derived directly from the visible remote sensing reflectance;then the Sg is extrapolated to obtain the spectrum from UV to visible spectral *** algorithm performs well,with an overall mean absolute percent difference(mAPD)of^30%,~5%and^6%for the estimation of ag in 250–450 nm,Sg over 250–400 nm,and 250–700 nm,*** effectiveness and stability of the algorithm is further demonstrated in capturing the distribution pattern of CDOm absorption in the PRE from satellite ocean color imagery with multiple spatial and spectral resolution,namely:the Visible infrared imaging Radiometer Suite(ViiRS)(750 m/multispectral),the Ocean and Land Color instrument(OLCi)(300 m/multispectral),the Hyperspectral imager for the Coastal Ocean(HiCO)(100 m/Hyperspectral),and the Landsat 8 Operational Land imager(OLi)(30 m/multispectral).The UV to visible scheme can benefit the CDOm absorption estimation in two aspects:1)it is free from the disturbance of suspended matter;2)it avoids uncertainties caused by the low signalto-noise ratio(SNR)of ag measurements in the visible *** algorithm is effective in revealing multiple scales of variation of CDOm absorption from ocean color observations.

关键词： Chromophoric dissolved organic matter ocean color remote sensing Pearl River Estuary ultraviolet

B(E2) value of even-even ^(108-112)Pd isotopes by interacting boson model-1

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Chinese Physics C 2014年第2期38卷 24-28页

作者： i.Hossain H.Y.Abdullah i.m.Ahmad m.A.Saeed Department of Physics Rabigh College of Science and Arts King Abdulaziz University Department of Physics College of Education Scientific Department Salahaddin University Department of Physics College of Education Mosul University Department of Physics Faculty of Science Universiti Teknologi Malaysia

This work studies the systematic reduced transition probabilities B（E2）↓, intrinsic quadrupole moments and deformation parameters of Pd isotopes with even neutrons from N =62 to 66. The downward reduced transition probabilities B（E2）↓from gamma transition 8^＋to 6^＋, 6^＋ to 4^＋, 4^＋ to 2^＋ and 2^＋ to 0＋states of even-even108 112Pd isotopes were calculated by the interacting Boson model（iBm-1） and compared with the available previous experimental results. The ratio of the excitation energies of the first 4＋and the first 2＋excited states, R4/2, is also studied for the classification of symmetry of these nuclei. Furthermore we have studied systematically the transition rate R = B（E2： L＋ →（L 2）＋）/B（E2 ： 2＋ →0＋） of some of the low-lying quadrupole collective states in comparison with the available experimental data. The associated quadrupole moments and deformation parameters have been calculated. The results of this calculation are in good agreement with the corresponding available experimental data. The108 112Pd isotopes show the O（6） symmetry.

关键词： B(E2) ground-states Pd isotopes.quadrupole moments deformation parameter

High-temperature deformation behaviour of duplex stainless steel with hard boronised layer

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Journal of iron and Steel Research international 2021年第2期28卷 244-253页

作者： N.m.Sultan i.Jauhari R.Saidan m.F.m.Sabri Department of mechanical Engineering Faculty of EngineeringUniversity MalayaKuala Lumpur 50603Malaysia

in order to understand the high-temperature deformation behaviour of alloy having hard surface layer,thermo-mechanically treated duplex stainless steel(DSS)is boronised for 0.75-6 h at 1223 K and subsequently deformed under compression mode at the same temperature under strain rate condition of 1×10^(-3),2×10^(-4) and 6×10^(-5) s^(-1) until strain of *** substrate microstructure is almost isotropic with grain size after boronising with layer thickness between 1.61 and 2.74μm.X-ray diffraction results confirm the formation of boride on DSS *** surface hardness of DSS increases from 387 to 1000-2400 HV after *** boronised layer with thickness of 20-40μm is formed at DSS *** results show that the flow stress of the deformation increases with the strain rate and boronising *** the boronised samples,the flow stress range is between 5 and 89 *** determine the actual effect of the boronised layer on the flow stress,the results are also compared with those from un-boronised samples having similar *** results suggest that at a constant grain size,even with the hardest layer,the effect of hard surface layer on the flow stress almost could be negligible when the deformation rate is slow,but at faster deformation rate,even in the layer with the least hardness,the flow stress shows a significant *** is also observed that the hard boride surface disintegration could be avoided at a sufficiently low deformation flow stress that could be attributed to superplasticity.

关键词： High-temperature deformation Superplasticity Duplex stainless steel Hard boride layer Surface integrity Grain size effect Strain rate effect

Environmental variation shifts the relationship between trees and scatterhoarders along the continuum from mutualism to antagonism

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integrative Zoology 2018年第3期13卷 319-330页

作者： Gina m.SAWAYA adam S.GOLDBERG michael A.STEELE Harmony J.DALGLEiSH Department of Biology College of William and MaryWilliamsburgVirginiaUSA Department of Biology Wilkes UniversityWilkes-BarrePennsylvaniaUSA

The conditional mutualism between scatterhoarders and trees varies on a continuum from mutualism to antagonism and can change across time and space,and among *** examined 4 tree species(red oak[Quercus rubra],white oak[Quercus alba],American chestnut[Castanea dentata]and hybrid chestnut[***×Castanea] mollissima)across 5 sites and 3 years to quantify the variability in this conditional *** used a published model to compare the rates of seed emergence with and without burial to the probability that seeds will be cached and left uneaten by scatterhoarders to quantify variation in the conditional mutualism that can be explained by environmental variation among sites,years,species,and seed provenance within *** species tested had increased emergence when ***,comparing benefits of burial to the probability of caching by scatterhoarders indicated a mutualism in red oak,while white oak was nearly always *** was variable around the boundary between mutualism and antagonism,indicating a high degree of context dependence in the relationship with *** found that different seed provenances did not vary in their potential for *** did not explain microsite differences in seed emergence in any of the species *** hybrid chestnut only,emergence on the surface declined with soil moisture in the *** quantifying the variation in the conditional mutualism that was not caused by changes in scatterhoarder behavior,we show that environmental conditions and seed traits are an important and underappreciated component of the variation in the relationship between trees and scatterhoarders.

关键词： Castanea dentata conditional mutualism Quercus alba Quercus rubra temperate forest

Adenosine-treated bioprinted muscle constructs prolong cell survival and improve tissue formation

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Bio-Design and manufacturing 2021年第3期4卷 441-451页

作者： Dongxu Ke adam m.Jorgensen Sang J.Lee James J.Yoo Sean V.murphy Wake Forest institute for Regenerative medicine Wake Forest School of MedicineWinston-SalemNCUSA Novaprint Therapeutics Suzhou Co. LtdSuzhouJiangsuChina

it is crucial to maintaining the viability of biofabricated human-sized tissues to ensure their successful survival and function after *** is a purine nucleoside that has the function to suppress cellular metabolism and has been previously proposed as a method to prolong cell viability under *** this study,we optimized the dose concentration of adenosine for incorporation into bioprinted constructs to preserve long-term cell viability in *** results showed that muscle cells(C2C12)containing 6,7,or 8 mm adenosine maintained high cell viability for 20 days under hypoxic conditions(0.1%O2),whereas cells without adenosine treatment showed 100%cell death after 11 *** 20 days under hypoxic conditions,muscle cells treated with adenosine proliferated and differentiated when transferred to normoxic *** these adenosine concentrations,6 mm was picked as the optimized adenosine concentration for further investigations due to its most effective results on improving cell *** bioprinted muscle constructs containing adenosine(6 mm)maintained high cell viability for 11 days under hypoxic conditions,while the control constructs without adenosine had no live *** in vivo validation,the bioprinted constructs with adenosine implanted under the dorsal subcutaneous space in mice,showed the enhanced formation of muscle tissue with minimal central necrosis and apoptosis,when compared to the constructs without *** positive in vitro and in vivo results demonstrate that the use of adenosine is an effective approach to preventing the challenge of hypoxia-induced necrosis in bioprinted tissues for clinical translation.

关键词： Bioprinting Hypoxia Adenosine Cell viability in vivo

Effects of symmetric and asymmetric salt conditions on a selective solid-state nanopore assay

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Nano Research 2022年第11期15卷 9936-9942页

作者： ian D.Wadsworth adam R.Hall Virginia Tech-Wake Forest University School of Biomedical Engineering and Sciences Wake Forest School of MedicineWinston-SalemNC 27101USA Comprehensive Cancer Center Wake Forest School of MedicineWinston-SalemNC 27157USA

Conventional solid-state nanopore measurements sense all translocating entities,necessitating meticulous analysis to differentiate target *** address this,we have established a selective assay with the platform that has shown utility in quantifying several nucleic acid ***,limited detection efficiency and intrinsic noise have so far limited assay resolution to 10 *** in this value require manipulation of translocation ***,we report the effects of NaCl conditions on assay *** first investigate symmetric conditions,finding sensitivity increases with salt concentration but selectivity is maximized at 1.0 m *** then probe asymmetric conditions,showing a remarkable impact on assay sensitivity and selectivity when measurement buffer NaCl concentration in the reservoir with the translocating molecules is low and the opposite reservoir is *** optimum conditions,we demonstrate detection of target biomolecules down to a concentration of 100 pm which is an improvement of 2 orders of magnitude over past results.

关键词： solid-state nanopores biomarkers amplification-free detection salt gradient nucleic acids

The giant Jiaodong gold province： The key to a unified model for orogenic gold deposits？

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Geoscience Frontiers 2016年第3期7卷 409-417页

作者： David i.Groves m.Santosh Centre for Exploration Targeting UWA Cmwley 6009 WA Australia Centre for Tectonics Resources and Exploration Department of Earth Sciences University of Adelaicle SA 5005 Australia State Key Laboratory of Geological Processes and mineral Resources China University of Geosciences Beijing 100083 China Division of interdisciplinary Science Faculty of Science Kochi University Kochi 780-8520 Japan

Although the term orogenic gold deposit has been widely accepted for all gold-only lode-gold deposits,with the exception of Carlin-type deposits and rare intrusion-related gold systems,there has been continuing debate on their *** syngenetic models and hydrothermal models dominated by meteoric fluids are now clearly ***-hydrothermal models fail to explain the genesis of orogenic gold deposits because of the lack of consistent spatially- associated granitic intrusions and inconsistent temporal *** most plausible,and widely accepted,models involve metamorphic fluids,but the source of these fluids is hotly *** within deeper segments of the supracrustal successions hosting the deposits,the underlying continental crust,and subducted oceanic lithosphere and its overlying sediment wedge all have their *** orogenic gold deposits of the giant Jiaodong gold province of China,in the delaminated North China Craton,contain ca.120 ma gold deposits in Precambrian crust that was metamorphosed over 2000 million years prior to gold *** only realistic source of fluid and gold is a subducted oceanic slab with its overlying sulfide-rich sedimentary package,or the associated mantle *** could be viewed as an exception to a general metamorphic model where orogenic gold has been derived during greenschist- to amphibolite-facies metamorphism of supracrustal rocks：basaltic rocks in the Precambrian and sedimentary rocks in the ***,if a holistic view is taken,Jiaodong can be considered the key orogenic gold province for a unified model in which gold is derived from late-orogenic metamorphic devolatilization of stalled subduction slabs and oceanic sediments throughout Earth *** latter model satisfies all geological,geochronological,isotopic and geochemical constraints but the precise mechanisms of auriferous fluid release,like many other subduction-related processes,are model-driv

关键词： Jiaodong province Orogenic gold metamorphic fluids Subduction zones Tectonics

Province-scale commonalities of some world-class gold deposits:implications for mineral exploration

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Geoscience Frontiers 2015年第3期6卷 389-399页

作者： David i.Groves m.Santosh Centre for Exploration Targeting UWA State Key Laboratory of Geological Processes and mineral Resources China University of Geosciences Centre for Tectonics Resources and Exploration Dept.of Earth SciencesUniversity of Adelaide Division of interdisciplinary Science Faculty of ScienceKochi University

Discovery rates for all metals, including gold, are declining, the cost per significant discovery is increasing sharply, and the economic situation of the industry is one of low base rate. The current hierarchical structure of the exploration and mining industry makes this situation difficult to redress. Economic geologists can do little to influence the required changes to the overall structure and philosophy of an industry driven by business rather than geological principles, However, it should be possible to follow the lead of the oil industry and improve the success rate of greenfield exploration, necessary for the next group of lower-exploration-spend significant mineral deposit discoveries. Here we promote the concept that mineral explorers need to carefully consider the scale at which their exploration targets are viewed. it is necessary to carefully assess the potential of drill targets in terms of terrane to province to district scale, rather than deposit scale, where most current economic geology research and conceptual thinking is concentrated. if orogenic, iRGD, Carlin-style and iOCG gold-rich systems are viewed at the deposit scale, they appear quite different in terms of conventionally adop- ted research parameters. However, recent models for these deposit styles show increasingly similar source-region parameters when viewed at the lithosphere scale, suggesting common tectonic settings. it is only by assessing individual targets in their tectonic context that they can be more reliably ranked in terms of potential to provide a significant drill discovery. Targets adjacent to craton margins, other lithosphere boundaries, and suture zones are clearly favoured for all of these gold deposit styles, and such exploration could lead to incidental discovery of major deposits of other metals sited along the same tectonic boundaries.

关键词： mineral exploration Gold deposits Tectonic settings mining industry Discovery rate

Computer modelling of metal Dissolution in the Presence of Aqueous Electrolyte

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Chinese Physics Letters 2002年第3期19卷 389-390页

作者： R.i.Eglitis m.R.Philpott UniversitatOsnabruck FachbereichPhysikD-49069OsnabruckGermany DepartmentofmaterialsScience NationalUniversityofSingapore10KentRidgeCrescentSingapore119260

The semi-empirical Hartree-Fock intermediate neglect of differential overlap (iNDO) method was used to explore the potential energy surface of adsorbed water molecules and to speculate, using fairly simple cluster models, on the reaction path followed by metal ions leaving the surface. As an example, iNDO calculations were used to calculate the potential energy curve for a metal atom leaving the surface and entering into a solvation cage composed of tetrahedral arranged water molecules. The effect of adding a NaCl ion pair to the system with the halide ion above the dissolving atom was also explored.

关键词： metals