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Synthesis of ZrSiN composite films using a plasma focus device

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Chinese Physics B 2014年第6期23卷 381-386页

作者： r.Ahmad t.Hussain I.A.Khan r.S.rawat Center for Advanced Studies in Physics GC University Physics Department GC Universit National Institute of Education Nanyang Technological University

ZrSiN thin films are synthesized by using plasma focus through various numbers of focus shots （10, 20, and 30）, with samples placed at 9 cm away from the tip of the anode. Crystal structures, surface morphologies, and elemental compositions of ZrSiN films are characterized by an X-ray diffractometer （XrD） and scanning electron microscope （SEM） attached with energy dispersive X-ray spectroscopy （EDS）. XrD patterns confirm the formations of polycrystalline ZrSiN films. Crystallinity of nitride increases with the increase of focus shot number. the average crystallite size of zirconium nitride increases from 27 ± 3 nm to 73±8 nm and microstrain decreases from 2.28 to 1.0 with the increase of the focus shot number. SEM results exhibit the formations of granular and oval-shaped microstructures, depending on the number of focus shots. EDS results confirm the presences of silicon, zirconium, nitrogen, and oxygen in the composite films. the content values of Zr and N in the composite films increase with the increase of the focus shot number.

关键词： DPF ZrSiN thin films XrD SEM

Stochastic earthquake source model for ground motion simulation

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Earthquake Engineering and Engineering Vibration 2019年第1期18卷 1-34页

作者： P.r.Lekshmy S.t.G.raghukanth Department of Civil Engineering

In the analysis and design of important structures with relatively long life spans, there is a need to generate strong motion data for possible large events. the source of an earthquake is characterized by the spatial distribution of slip on the fault plane. For future events, this is unknown. In this paper, a stochastic earthquake source model is developed to address this issue. Here, 1D and 2D stochastic models for slip distribution developed by Lavallée et al.(2006) are used. the random field associated with the slip distribution is heavy-tailed stable distribution which can be used for large events. Using 236 past rupture models, the spectral scaling parameter and the four stable or Levy's parameters against empirical relationship for known quantities like magnitude or fault length are developed. the model is validated with data from 411 stations of 1999 Chi-Chi earthquake. the simulated response spectrum showed good agreement to actual data. Further the proposed model is used to generate ground motion for the 1993 Killari Earthquake where strong motion data is not available. the simulated mean peak ground velocity was in turn related to the intensity(MSK) and compared against values in the literature.

关键词： stochastic slip distribution ground motion Levy’s parameters Killari earthquake

Basis for the diversity and extent in loss of digestible nutrients created by dietary phytin:Emphasis on fowl and swine

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Animal Nutrition 2024年第1期16卷 422-428页

作者： Edwin t.Moran Michael r.Bedford Poultry Science Department Auburn UniversityAL36830-5416USA AB Vista Woodstock CourtBlenheim RoadMarlboroughWiltshireSN84ANUK

Phytin is the Ca^(2+)-Mg^(2+)-K^(+)salt of phytic acid that is created and deposited in the aleurone layer and/or germ of grains and *** high presence in feedstuffs for fowl and swine diets results in it being a universal and significant impediment to optimum *** impairs gastrointestinal recovery of a wide array of nutrients,the effect varying with the nutrient *** exposure to low pH during gastric digestion,phytin dissociates into phytic acid and solubilized Ca^(2+).Even at low gastric pH,phytic acid is negatively charged which forms the basis of its anti-nutritive *** has extensive basic amino acids on its activation peptide that are presented as cations at low pH which are targeted by pepsin for *** crystalized Ca^(2+)near the enzyme?s active site further stabilizes its newly formed ***,phytic acid appears to interfere with gastric digestion by several mechanisms;interfering with pepsinogen activation by binding to the polypeptide?s basic amino acids;coordinating free Ca^(2+),destabilizing pepsin;binding some dietary proteins directly,further compromising gastric *** digesta attaining neutrality in the duodenum,Ca^(2+)and other cations rebind with accessible anions,phytic acid being a significant *** not only binds free cations but can also strip them from enzymes(***^(2+),Zn2+)which reduces their structural resistance to autolysis and ability as co-factors(***2+)to increase enzyme *** cells initially employ Ca^(2+)as an electronic shield between mucin layers enabling granule formation and cell *** mucin granule release,Ca^(2+)is progressively displaced by Na^(+)to free the viscous mucins enabling its *** entangles with the glycocalyx of adjacent enterocytes thereby constructing the unstirred water layer(USWL).Excessive removal of Ca^(2+)from mucin by phytic acid increases its fluidity facilitating its loss from the US

关键词： Digestive enzyme Calcium Endogenous protein Mucin Phytin

Endogenous mucin conveyed to the mucosa with microbes can assure lumen fermentation and large intestinal security-swine versus fowl

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Animal Nutrition 2023年第3期14卷 403-410页

作者： Edwin t.Moran Michael r.Bedford Poultry Science Department Auburn UniversityAL 36849-5416USA AB Vista Woodstock CourtBlenheim RoadMarlborough RoadWiltshireSN84NAUK

Endogenous protein leaving the ileum largely consists of accrued mucins from the upper gastrointestinal tract(GIt)that had resisted *** amounts released rely on their mucosal generation during enteral feeding which vary with age as well as *** digestion resistant proteins of endogenous origin continue to be unavailable in the large intestine,whereas those of dietary origin provide amino acids that largely support the existing microbial population while denying limited amounts for *** mucins pre-exist within the large intestine as two layers at the lumen surface.A loose layer harboring a diverse microbial population is superimposed on the unstirred water layer(USWL)which simultaneously acts as an obstacle to microbes at the loose layer while performing as a molecular sieve for *** USWL is formed through interplay between enterocyte and goblet cells;however,the basis for presence of the loose layer is *** intestinal fermentation predominates within the colon of swine,whereas fowl employ their *** within the colon of swine segregates fine materials into haustrae out-pocketings that parallel their placement within the ceca of *** mucins from small intestinal endogenous losses may envelop microbes within the large intestinal lumen to present successive adherents on the USWL that assemble its loose *** loose layer continually functions as a microbial reservoir in support of lumen *** catabolism of mucin within the loose layer is known to be slow,but its proximity to the enterocyte is of advantage to enterocyte absorption with by-product amino acids fostering the USWL.

关键词： Endogenous protein Enterocyte Goblet cell Mucin Large intestine

An important criterion for reliable multi-monochromatic x-ray imager diagnostics and its impact on the reconstructed images

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High Power Laser Science and Engineering 2015年第3期3卷 59-65页

作者： t.Nagayama r.C.Mancini D.Mayes r.tommasini r.Florido Physics Department University of Nevada Lawrence Livermore National Laboratory Departamento de Física Universidad de Las Palmas de Gran Canaria

temperature and density asymmetry diagnosis is critical to advance inertial confinement fusion(ICF) science. A multimonochromatic x-ray imager, MMI, records the spectral signature from an ICF implosion core with time resolution, 2D spatial resolution and spectral resolution. While narrow-band images and 2D space-resolved spectra from the MMI data constrain the temperature and the density spatial structure of the core, the accuracy of the images and the spectra highly depends on the quality of the MMI data and the processing tools. Here, we synthetically investigate the criterion for reliable MMI diagnostics and its effects on the accuracy of the reconstructed images. the pinhole array tilt determines the object spatial sampling efficiency and the minimum reconstruction width, w. When the spectral width associated with w is significantly narrower than the spectral linewidth, the line images reconstructed from the MMI data become reliable. the MMI setup has to be optimized for every application to meet this criterion for reliable ICF diagnostics.

关键词： high power laser inertial confinement fusion monochromatic imager x-ray diagnostics

Mixed convection boundary layer flow past vertical flat plate in nanofluid: case of prescribed wall heat flux

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Applied Mathematics and Mechanics(English Edition) 2015年第8期36卷 1091-1104页

作者： r.trIMBItAS t.GrOSAN I.POP Department of Mathematics Babes-Bolyai University

An analysis is carried out to investigate the steady mixed convection bound- ary layer flow of a water based nanofluid past a vertical semi-infinite flat plate. Using an appropriate similarity transformation, the governing partial differential equations are transformed into the coupled, nonlinear ordinary （similar） differential equations, which are then solved numerically for the Prandtl number Pr = 6.2. the skin friction coeffi- cient, the local Nusselt number, and the velocity and temperature profiles are presented graphically and discussed. Effects of the solid volume fraction φ and the mixed convection parameter λ on the fluid flow and heat transfer characteristics are thoroughly examined. Different from an assisting flow, it is found that the solutions for an opposing flow are non-unique. In order to establish which solution branch is stable and physically realizable in practice, a stability analysis is performed.

关键词： Nanofluid boundary layer mixed convection heat flux dual solution

Evaluation of unconstrained and constrained mathematical functions to model girth growth of rubber trees (Hevea brasiliensis) using young agemeasurements

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Journal of Forestry research 2012年第3期23卷 365-375页

作者： t.r.Chandrasekhar rubber research Institute of India Hevea Breeding Sub StationKadaba-574221DK DistrictKarnatakaIndia

No attempt has been made to date to model growth in girth of rubber tree （Hevea brasiliansis）. We evaluated the few widely used growth functions to identify the most parsimonious and biologically reasonable model for describing the girth growth of young rubber trees based on an incomplete set of young age measurements. Monthly data for girth of immature trees （age 2 to 12 yearsi from two locations were sub- jected to modelling. re-parameterized, unconstrained and constrained growth functions,of richards （rM）, Gompertz （GM） and the monomo- lecular ＇model ^（MM） were fitted to data. Duration of growth was the firsf constraint introduced. In the stagel We attempted a population aver- age （PA） model to capture the trend in growth. the best PA model was fitted as a subject specific （SS） model. We used appropriate error vari- ance-covariance structure to account for correlation due to repeated measurements over time. Unconstrainecl functions underestimated the asymptotic maximum that did not reflective carrying capacity of the locations. Underestimafions were attributed to the partial set＇ of meas- urements made during the early growth phase of the trees. MM proved superior to rM and GM. In the randomcoefficient models, both Gf and Go appeared to be influenced by tree level effects. Inclusion of diagonal definite positive matrix removed the correlation between random effects. the results were similar at both locations. In the overall assessment MM appeared as the candidate model for studying the girth-age relationships in Hevea trees. Based on the fitted model we conclude that, in Hevea trees, growth rate is maintained at maximum value at to, then decreases until the final state at dG/dt 〉 0, resulting in yield curve with no period of accelerating growth. One physiological explanation is that photosynthetic activity in Hevea trees decreases as girth increases and constructive metabolism is larger than destructive metabolism.

关键词： natural rubber Hevea Brasiliensis growth modelling un-constrained functions constrained functions mixed model

Effects of casting factors of cooling slope on semisolid condition

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中国有色金属学会会刊：英文版 2010年第S3期20卷 968-972页

作者： t.HAGA r.NAKAMUrA r.tAGO H.WAtArI Department of Mechanical Engineering Osaka Institute of Technology5-16-1 Omiya Asahi-kuOsaka City 535-8585Japan Department of Production Science and technology Gunma University Tenjin-choKiryu City 376-8515Japan

the effects of the casting factors such as nozzle size to pour the melt,nozzle height,tilt of the slope and slope length,of the cooling slope on the process to make semisolid slurry were *** results show that these factors affect the behaviors of the semisolid slurry on the cooling *** tilt of the slope is the factor that has major influence on the behavior of the semisolid *** cooling roll is developed from the result of the research of the cooling *** rotating cooling roll can improve the sticking of the semisolid slurry on the substrate and it is suitable for making the semisolid slurry.

关键词： casting factors cooling roll semisolid slurry cooling slope

Fuzzy Based Intelligent Monitoring of Critical Lines in the restructured Power Market

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Circuits and Systems 2016年第9期7卷 2196-2206页

作者： S. rajasekaran S. Sathiyamoorthy Department of Electrical & Electronics Engineering M.A.M College of Engineering and Technology Anna University Chennai India Department of Electronics & Instrumentation Engineering J.J College of Engineering and Technology Anna University Chennai India

restructured electric market environment allows the power wheeling transactions between the power producers and customers to meet the growing load demand. this will lead to the possible of congestion in the transmission lines. the possible contingencies of power components further worsen the scenario. this paper describes the methodology for the identification of critical transmission line by computing the real power and reactive power performance indices. It also demonstrates the importance of fuzzy logic technique used to rank the transmission lines according to the severity and demonstrated on IEEE-30 bus system.

关键词： Contingency Analysis Active Power Performance Index reactive Power Performance Index Fuzzy Logic Wheeling transaction