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Decay rates and electromagnetic transitions of heavy quarkonia

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Chinese Physics C 2015年第12期39卷 19-24页

作者： j.n.Pandya n.R.Soni n.Devlani A.K.Rai Applied Physics Department Faculty of Technology & Engineeringthe M S University of Baroda Applied Physics Department Polytechnicthe M S University of Baroda Department of Applied Physics Sardar Vallabhbhai National Institute of Technology

The electromagnetic radiative transition widths for heavy quarkonia, as well as digamma and digluon decay widths, are computed in the framework of the extended harmonic confinement model （ERHM） and Coulomb plus power potential （CPP,） with varying potential index v. The outcome is compared with the values obtained from other theoretical models and experimental results. While the mass spectra, digamma and digluon widths from ERHM as well as CPP v=1 are in good agreement with experimental data, the electromagnetic transition widths span over a wide range for the potential models considered here making it difficult to prefer a particular model over the others because of the lack of experimental data for most transition widths.

关键词： heavy quarkonia radiative decays electromagnetic transitions

Water Resource Management in the Intermountain Izeh Plain,Southwest of Iran

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journal of Mountain Science 2009年第1期6卷 25-41页

作者： Kalantari.n Pawar.n.j Keshavarzi.M.R Geology Department Shahid Chamran UniversityAhvazIran Geology Department University of PunePune-411 007India

Ever growing demand for water for agricultural activities in the Izeh Plain has enhanced the use of groundwater. Due to enormous groundwater abstraction since 1985, the overall static water level has receded by more than 5 meters reflecting that the aquifer is under stress condition. As a result, interest is focused on application of artificial recharge as an option for groundwater management to augment water supply in this area. Therefore, in the present investigations, suitable sites for artificial recharge were selected by an integrated surface and sub-surface assessment of the area. On the basis of the data collected from four target points, it was realized that the selected sites for artificial recharge could not meet water demand of the area. In this study attention was also paid to utilization of the existing Miangran Lake water as an alternative to combat water shortage for irrigation. The study further indicated that the available Miangran Lake water could be used for irrigation of the reclaimed agricultural land and enabling to convert 20o0 hectares of rain-fed land into irrigation. The total cost to utilize lake water is US$ 2,756,729 and it was estimated that the project could recoup the investment within 5 years which is quite reasonable in this water scarcity prone area.

关键词： Artificial recharge stream MiangranLake groundwater Izeh Plain

Kinetics of Hydrogen Molecules in MAGnUM-PSI

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Plasma Science and Technology 2008年第2期10卷 162-169页

作者： M.BAEVA W.j.GOEDHEER n.j.LOPES CARDOZO Leibniz Institute for Plasma Science and Technology Felix-Hausdorf-Str. 2 D-17489 Greifswald Germany FOM-Institute for Plasma Physics Rijnhuizen Association EURATOM-FOM Trilateral Euregio Cluster P. O. Box 1207 3430 BE Nieuwegein The Netherlands

Results from simulations of plasma and neutrals under conditions predictively characterizing the detached plasma regime in the linear machine MAGnUM-PSI are presented. The relaxation of the vibrationally excited hydrogen molecules is investigated in order to establish a relation between their relaxation and dwell times, and the role of the varions mechanisms of the molecular vibrational kinetics. Tile results obtained show that the individual vibrational states have to be inclllded in the transport code for neutrals as distinct species, since the relaxation time of tile vibrational states is sufficiently longer than the typical dwell time of hydrogen molecules in the detached plasma region. The parameters of plasma and neutrals are affected by the transport of the vibrationally excited hydrogen lnolecnles. Furthermore. the rate of molecular reconlbination is overestimated by a factor of - 5 provided that the transport of ilydrogen molecules only in their ground vibrational state is considered. The role of the various processes of vibrational kinetics is studied. The vibrational excitation through singlet electronic states ires a strong influence on the molecular densities for levels with vibrational quantum numbers v≥ 5. Vibration-vibration （V-V） collisions between vibrationally excited hydrogen molecules and vibration-translation （V-T） collisions between vibrationally excited hydrogen molecules and ground state molecules and atoms are of nlinor importance in MAGnUM-PSI.

关键词： vibrational relaxation hydrogen molecules. B2-Eirene simulation detached plasma

Strategies towards robust interpretations of in situ zircon Lu-Hf isotope analyses

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Geoscience Frontiers 2020年第3期11卷 843-853页

作者： C.j.Spencer C.L.Kirkland n.M.W.Roberts n.j.Evans j.Liebmann School of Earth and Planetary Sciences The Institute for Geoscience Research(TIGeR)Curtin UniversityPerthAustralia Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonCanada Centre for Exploration Targeting-Curtin node The Institute for Geoscience ResearchSchool of Earth and Planetary SciencesCurtin UniversityPerthAustrali Geochronology and Tracers Facility British Geological SurveyNottinghamUK john de Laeter Centre GeoHistory Facility School of Earth and Planetary SciencesCurtin UniversityPerthAustralia

The combination of U-Pb and Lu-Hf compositions measured in zircon crystals is a remarkably powerful isotopic couplet that provides measures on both the timing of mineral growth and the radiogenic enrichment of the source from which the zircon *** U-Pb age documents the timing of zircon crystallization/recrystallization and Hf isotopes inform on the degree to which the host melt was derived from a radiogenic reservoir(*** mantle) versus an unradiogenic reservoir(*** continental crust),or some mixture of these *** ease of generating large quantities of zircon U-Pb and Lu-Hf data has been in large part facilitated by instrument ***,the dramatic increase in time constrained zircon Lu-Hf analyses in the Earth science community has brought to the fore the importance of careful data collection and reduction workflows,onto which robust geological interpretations may be *** this work,we discuss the fundamentals of Lu-Hf isotopes in zircon,which then allows us to provide a robust,accessible,methodology for the assessment of data ***,we discuss some novel techniques for:data visualization—that facilitates better transparency of data interpretation;integration of geographic information—that may reveal spatial trends where temporal trends were only apparent before;and some novel statistical evaluation tools—that may provide more rigorous interand intra-sample comparisons.

关键词： Zircon Geochronology Isotope geochemistry Lu-Hf isotopes Geostatistics Data visualization

Effect of null aether field on weak deflection angle of black holes

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Chinese Physics C 2020年第12期44卷 234-239页

作者： A.Övgün İ.Sakallı j.Saavedra Physics Department Faculty of Arts and SciencesEastern Mediterranean University99628 FamagustaNorth Cyprusvia Mersin 10Turkey Instituto de Física Pontificia Universidad Católica de ValparaísoCasilla 4950ValparaísoChile

We study light rays in the static and spherically symmetric gravitational field of the null aether theory(nAT).To this end,we employ the Gauss-Bonnet theorem to compute the deflection angle formed by a nAT black hole in the weak limit *** the optical metrics of the nAT black hole,we first obtain the Gaussian curvature and then calculate the leading terms of the deflection *** calculations indicate how gravitational lensing is affected by the nAT *** also illustrate that the bending of light stems from global and topological effects.

关键词： deflection of light Gauss-Bonnet theorem gravitational lensing black hole null aether theory

Deep convolutional Ritz method: parametric PDE surrogates without labeled data

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Applied Mathematics and Mechanics(English Edition) 2023年第7期44卷 1151-1174页

作者： j.n.FUHG A.KARMARKAR T.KADEETHUM H.YOOn n.BOUKLAS Sibley School of Mechanical and Aerospace Engineering Cornell UniversityNew York 14853U.S.A Geomechanics Department Sandia National LaboratoriesAlbuquerque 87123U.S.A.

The parametric surrogate models for partial differential equations(PDEs)are a necessary component for many applications in computational sciences,and the convolutional neural networks(Cnns)have proven to be an excellent tool to generate these surrogates when parametric fields are *** are commonly trained on labeled data based on one-to-one sets of parameter-input and PDE-output ***,residual-based deep convolutional physics-informed neural network(DCPInn)solvers for parametric PDEs have been proposed to build surrogates without the need for labeled *** allow for the generation of surrogates without an expensive *** this work,we present an alternative formulation termed deep convolutional Ritz method(DCRM)as a parametric PDE *** approach is based on the minimization of energy functionals,which lowers the order of the differential operators compared to residualbased *** on studies involving the Poisson equation with a spatially parameterized source term and boundary conditions,we find that Cnns trained on labeled data outperform DCPInns in convergence speed and generalization *** surrogates generated from the DCRM,however,converge significantly faster than their DCPInn counterparts,and prove to generalize faster and better than the surrogates obtained from both Cnns trained on labeled data and *** hints that the DCRM could make PDE solution surrogates trained without labeled data possibly.

关键词： physics-informed constraint physics-informed neural network(PInn) deep energy network convolutional neural network(Cnn)

A review of the effects of dietary organic acids fed to swine

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journal of Animal Science and Biotechnology 2016年第1期7卷 67-77页

作者： Mocherla V A n Suiryanrayna j V Ramana Livestock Research Station Sri Venkateswara Veterinary University

Animal production depends on nutrient utilization and if done there is an accelerated momentum towards growth with a low cost to feed ratio Public concern over the consumption of pork with antibiotic residues of the animals fed with antibiotic growth promoters （AGP） has paved the way to use other additives like herbs and their products, probiotics, prebiotics etc. numerous feed additives are in vogue for achieving this target and one such classical example is the usage of organic acids and their salts. Usage of organic acids was in progress for over four decades. Early weaned piglets are （3-4 weeks age） exposed to stress with a reduced feed intake, little or no weight gain. This post weaning lag period is due to a limited digestive and absorptive capacity due to insufficient production of hydrochloric acid, pancreatic enzymes and sudden changes in feed consistency and intake. Lowering dietary pH by weak organic acids was found to overcome these problems. The main activity of organic acids is associated with a reduction in gastric pH converting the inactive pepsinogen to active pepsin for effective protein hydrolysis. Organic acids are both bacteriostatic and bactericidal. Lactic acid has been reported to reduce gastric pH and delay the multiplication of an enterotoxigenic E. coil These acids are the intermediary products in Kreb＇s cycle and thus act as an energy source preventing the tissue breakdown resulting from gluconeogenesis and lipolysis. Excretion of supplemental minerals and nitrogen are minimized with organic acids as these form complexes with minerals and aids for their bio-availability. Short chain fatty cids like acetic, propionic and n-butyric acid produced by microbial fermentation of dietary fibre in the large intestines may increase the proliferation of epithelial cells and have stimulatory effects on both endocrine and exocrine pancreatic secretions in pigs. Organic acids also enhances apparent total tract digestibility and improves growth performa

关键词： Chelation Improved productivity Organic acids Pathogen inhibition Protein utility Swine

A review of development of better prediction equations for blast fragmentation

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journal of Rock Mechanics and Geotechnical Engineering 2019年第5期11卷 1094-1109页

作者： F.Ouchterlony j.A. Sanchidrián Department of Mining Engineering and Mineral Economics Montanuniversitaet Leoben Leoben Austria ETSI Minas Universidad Politécnica de Madrid Madrid Spain

The paper reviews the development of prediction formulas for the fragmentation from bench *** attention has been paid to the Kuz-Ram model,its development and errors,and the mean *** *** work by the US Bureau of Mines(USBM)and Chung and Katsabanis are also reviewed,as well as the two julius Kruttschnitt Mineral Research Centre(jKMRC)models,*** crush zone model(CZM)and the two-component model(TCM),which were developed to cope with the underestimation of blasting *** change brought by the Swebrec distribution and the associated Kuznetsov-Cunningham-Ouchterlony(KCO)model is *** distribution-free fragment sizes xP for an arbitrary mass passing P led to the discovery of the fragmentation-energy fan,and with the help of dimensional analysis,to the new fragmentation prediction model xP-frag,which has much lower errors than those of the Kuz-Ram and CZM models.

关键词： Bench blasting Rock fragmentation Fragmentation model Size distribution Swebrec function Fragmentation-energy fan

An ethnobotanical study of medicinal plants in Güce district,north-eastern Turkey

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Plant Diversity 2022年第6期44卷 577-597页

作者： Mustafa Karakose Giresun University Espiye Vocational SchoolProgramme of Medicinal and Aromatic PlantsEspiyeGiresun28600Turkey

This study aims to identify medicinal plants traditionally used to treat diseases by local people living in Güce district,north-eastern *** study was carried out between 2018 and 2021 using a two-part semi-structured,open-ended questionnaire with 165 local *** were analysed using use-report,frequency of citation,and informant consensus *** identified 128 vascular medicinal plant taxa belonging to 54 families and 106 *** most common plant taxa belong to Rosaceae(16 taxa/12.5%),Asteraceae(12 taxa/9.4%),and Lamiaceae(9 taxa/7%)*** most frequently used preparation method reported was decoction(39.8%);the most commonly utilized plant parts were leaves(40.3%).Statistical analysis reveals that women in Güce district(df?163,p?0.043sess the most traditional *** highest frequency of citation(61)and use report(92)were recorded for Tilia rubra ***,and the highest informant consensus factors were cited for respiratory system disorders(0.86),digestive system disorders(0.73),and skin disorders(0.71).This study reported nine plant taxa as medicinal plants for the first time,and documented a total of 293 new therapeutic ***,the study indicates that the transfer of traditional knowledge to future generations is limited(F?3.355,p?0.020).Action should be taken as soon as possible to preserve existing traditional knowledge and to ensure its transfer to future generations.

关键词： Colchic Ethnobotany Informant consensus factor Frequency of citation Traditional medicine Use-record