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Metastable noble gas atoms in strong-field ionization experiments

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High Power Laser Science and engineering 2016年第3期4卷 74-100页

作者： j.e.Calvert A.j.Palmer I.V.Litvinyuk R.T.Sang Australian Attosecond Science Facility Center for Quantum Dynamics School of Natural Sciences Griffith University

The interactions of strong-field few-cycle laser pulses with metastable states of noble gas atoms are examined. Metastable noble gas atoms offer a combination of low ionization potential and a relatively simple atomic structure, making them excellent targets for examining ionization dynamics in varying experimental conditions. A review of the current work performed on metastable noble gas atoms is presented.

关键词： COLTRIMS electron holography high power lasers ionization regime metastable atoms spin polarized targets

An Application of Prony’s Sum of exponentials Method to Pharmacokinetic Data Analysis

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Communications in Computational Physics 2007年第1期2卷 87-98页

作者： j.Fuite R.e.Marsh j.A.Tuszynski Department of Physics University of AlbertaEdmontonAlbertaT6G 2J1Canada.

We discuss the basic concept of compartmental modelling in pharmacokinetics and demonstrate that all the solutions admitted by multi-compartment models of classical pharmacokinetics are expressed as linear combinations of exponential functions of *** lends itself to data analysis that depends on fitting exponential functions to finite size sets.A mathematical method developed a long time ago to deal with this type of problem is called Prony’s *** discuss the usefulness of this method in pharmacokinetic modeling and apply it to a particular data set obtained for the drug *** spite of the method’s power in dealing with well-behaved data sets,we indicate the existence of severe limitations since real concentration curves coming from pharmacokinetic data are seldom purely exponential.

关键词： Data analysis pharmacokinetics modelling Prony’s method.

Prediction of protein and amino acid composition and digestibility in individual feedstuffs and mixed diets for pigs using near-infrared spectroscopy

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Animal Nutrition 2021年第4期7卷 1242-1252页

作者： Samantha j.Noel Henry j.Høgh jørgensen Knud e.Bach Knudsen Department of Animal Science AU FoulumAarhus UniversityDK 8830TjeleDenmark

Knowledge of the amounts and digestibility of amino acids in pig feedstuffs is essential for calculating the appropriate inclusion level in a complete *** chemical analysis and in vivo digestibility trials are time-consuming and costly and cannot be used for routine ***-infrared spectroscopy(NIRS)offers a rapid,cost effective and environmentally friendly method for evaluating *** models were developed using NIRS to predict the content of crude protein and 18 amino acids from a wide range of feedstuffs used in pig production(n=607).The samples ranged from single feed ingredients(containing amino acids from 0.3 to 129.8 g/kg of dry matter)to feed mixtures(containing amino acids from 1.2 to 53.2 g/kg of dry matter).The predictive ability of the calibrations was tested with an independent dataset(n=150)and with ***,we compare these calibrations with calibrations developed on more narrowly defined groups of samples and with predictions from regression analysis of crude *** models were able to predict the concentrations of crude protein and 18 amino acids with good levels of precision and high coefficients of determination for calibration(RSQ^(CAL))from 0.91 to 0.99 and validation(RSQ^(VAL))from 0.87 to *** models were able to predict all amino acids except tryptophan and valine with greater accuracy than those from protein *** also developed calibration models to predict the apparent ileal and total tract digestibility of protein and amino *** the exception of tryptophan,RSQ values(>0.7)and standard error of cross validation(SeCV)values(ere obtained for the digestibility of most of the amino *** conclusion,NIRS can be used to predict crude protein and amino acid concentrations from a wide range of single ingredients and feed mixtures used for pig diets without separate models for each *** digestibility of protein and amino acids can be predicted with an

关键词： Near-infrared spectroscopy Amino acids Protein Apparent ileal digestibility Total tract digestibility Swine

Challenges and prospects of plastic waste management in Nigeria

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Waste Disposal and Sustainable energy 2019年第2期1卷 117-126页

作者： R.U.Duru e.e.Ikpeama j.A.Ibekwe Department of Pure and Industrial Chemistry University of Port HarcourtPort HarcourtNigeria 15791 Pebblebrook Drive BellevilleMI 48111USA Department of Oil and Gas Chemistry University of AberdeenAberdeenScotlandUK

The combined properties of low cost,lightweight,and resistance to chemicals and corrosion has increased the use of plastic materials for packaging and storage purposes in preference to other ***,there is a continued increase in their proportion in domestic solid wastes worldwide as well as the concern of their impacts on the *** developed and developing countries have put in place and continue to improve their plastic waste disposal,collection,and recycling methods to reduce these *** Nigeria with a population of about 186 million,there are little or no available data on the use of plastic materials in relation to city populations,their disposal,collection,and recycling *** are a few numbers of plastic waste recycling companies in a fewer number of cities and disposal practices for the greater percentage of the plastic wastes that are not captured for recycling possess immediate and future danger for the *** work reviews the consumption of plastics,its waste generation,collection,and treatment in Nigeria and a few selected *** problems associated with inadequate management of the wastes were emphasized and recommendations were proffered to not only highlight research and investment opportunities that are inherent in plastic waste management in Nigeria,but also provide a background for the formulation of sustainable regulatory policies by the government to address the problems.

关键词： Plastic waste Disposal Recycling environment Investment Waste management

enslaved Phase-Separation Fronts and Liesegang Pattern Formation

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Communications in Computational Physics 2011年第5期9卷 1081-1093页

作者： e.M.Foard A.j.Wagner Department of Physics North Dakota State UniversityFargoND 58105USA

We show that an enslaved phase-separation front moving with diffusive speeds U=C/√T can leave alternating domains of increasing size in their *** find the size and spacing of these domains is identical to Liesegang *** equal composition of the components we are able to predict the exact form of the pattern *** our knowledge this is the first fully analytical derivation of the Liesegang *** also show that there is a critical value for C below which only two domains are *** analytical predictions are verified by numerical simulations using a lattice Boltzmann method.

关键词： Liesegang phase separation front reaction diffusion pattern formation lattice Boltzmann Matalon-Packter

Benchmark for scale-resolving simulation with curved walls: the Taylor Couette flow

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Advances in Aerodynamics 2021年第1期3卷 281-298页

作者： Z.j.Wang e.jourdan Department of Aerospace engineering University of KansasLawrenceKS 66045USA

Flow between rotating concentric cylinders,or the Taylor Couette flow,has been studied extensively because of its rich physics,ranging from axisymmetric steady laminar flow,to fully developed turbulent *** the present study,we advocate the use of this problem as a benchmark case for scale-resolving simulation,such as large eddy simulation(LeS)and direct numerical simulation(DNS).The problem is attractive because of its simple geometry,simple boundary conditions,and complex physics involving wall-shear induced and centrifugal *** the wellknown fully developed channel flow,this problem has a curved wall boundary,and it is unnecessary to add a source term to the governing equations to sustain the fully developed turbulent flow.A p-refinement study for Re=4000 is performed first to establish DNS data,including the time history of enstrophy,which can be used as an accuracy and resolution indicator to evaluate numerical methods,and is orders of magnitude faster than using the mean flow quantities and Reynolds stresses to evaluate solution ***,an hp-refinement study is performed to establish the relative accuracy and efficiency of high-order schemes of various accuracy.

关键词： Large eddy simulation Direct numerical simulation High-order methods Navier-Stokes Taylor Couette flow

A vestigial pathway for sex differences in immune regulation

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Cellular & Molecular Immunology 2017年第7期14卷 578-580页

作者： Yun Liang j Michelle Kahlenberg johann e Gudjonsson Department of Dermatology University of MichiganAnn ArborMI 48109USA Division of Rheumatology Department of Internal MedicineUniversity of MichiganAnn ArborMI 48109USA

Autoimmune diseases have a strikingly higher prevalence in women compared to men,with approximately 80%of individuals affected with autoimmune diseases being *** nature of this sex-bias has remained unclear,but sex hormones have previously been implicated as the leading underlying *** this research highlight,we discuss a recently identified transcription factor。

关键词： diseases autoimmune prevalence

Measurement and analysis technologies for magnetic pulse welding： established methods and new strategies

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Advances in Manufacturing 2016年第4期4卷 322-339页

作者： j. Bellmann j. Lueg-Althoff S. Schulze S. Gies e. Beyer A. e. Tekkaya Institute of Manufacturing Science and engineering TUDresden 01062 Dresden Germany Fraunhofer Institute for Material and Beam Technology Winterbergstrasse 28 01277 Dresden Germany Institute of Forming Technology and LightweightConstruction TU Dortmund Baroper Strasse 30344227 Dortmund Germany

Magnetic pulse welding （MPW） is a fast and clean joining technique that offers the possibility to weld dissimilar metals, e.g., aluminum and steel. The high-speed collision of the joining partners is used to generate strong atomic bonded areas. Critical brittle intermetallic phases can be avoided due to the absence of external heat. These features attract the notice of industries performing large scale productions of dissimilar metal joints, like automo- tive and plant engineering. The most important issue is to guarantee a proper weld quality. Numerical simulations are often used to predict the welding result a priori. Nevertheless, experiments and the measurement of process parameters are needed for the validation of these data. Sensors nearby the joining zone are exposed to high pressures and intense magnetic fields which hinder the evaluation of the electrical output signals. In this paper, existing analysis tools for process development and quality assurance in MPW are reviewed. New methods for the process monitoring and weld characterization during and after MPW are introduced, which help to overcome the mentioned drawbacks of established technologies. These methods are based on optical and mechanical measuring technologies taking advantage of the hypervelocity impact flash, the impact pressure and the deformation necessary for the weld formation.

关键词： Magnetic pulse welding (MPW) Processmonitoring Collision conditions Dissimilar metaljoining Materials testing

New multi-phonon gamma vibrational bands in A～110 neutron-rich nuclei

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Science China(Physics,Mechanics & Astronomy) 2011年第S1期54卷 44-48页

作者： HAMILTON j H RAMAYYA A V RASMUSSeN j O HWANG j K YeOH e Y Department of Physics Vanderbilt University Nashville TN 37235 USA Lawrence Berkeley National Laboratory Berkeley CA 94720 USA Department of Physics Tsinghua University Beijing 100084 China

The high spin states of neutron-rich 103Nb, 107Tc and 109Tc nuclei in A^110 region have been investigated by measuring prompt γ-γ-γ coincident measurements populated with the spontaneous fission of 252Cf with the Gammasphere detector array. In 103Nb, one-phonon K = 9/2 and two-phonon K = 13/2 γ-vibrational bands have been identified. In 107Tc and 109Tc, one-phonon K = 11/2 and two-phonon K = 15/2 γ-vibrational bands, in which the zero-phonon bands are based on K=7/2 excited states, have also been identified. The two-phonon bands are first observed in odd-Z nuclei. The characteristics for these band structures have been discussed.

关键词： high spin states neutron-rich nucleus γ-vibrational bands