FINITELY GENERATED COMMUTATIVE ARCHIMEDEAN SEMIGROUPS

In this work commutative Archimedean finitely generated semigroups are characterized in terms of ideal extensions.     

DRAG ON SUBMICRON NANOPARTICLE AGGREGATES

A new procedure was developed for estimating the effective collision diameter of an aggregate composed of primary particles of any size. The coagulation coefficient of two oppositely charged particles was measured experimentally and compared with classic Fuchs theory, including a new method to account for particle non-sphericity. A second set of experiments were performed on well-defined nanoparticle aggregates at different stages of sintering, i.e. from the aggregate to the fully sintered stage. Here, electrical mobility was used to characterize the particle drag. The aggregates are being built from two different size-fractionated nanoparticle aerosols, the non-aggregated particles are discarded by an electrofilter and then they are passed through a furnace at concentrations low enough not to induce coagulation.     

ON THE EXISTENCE OF POSITIVE ENTIRE SOLUTIONS FOR SINGULAR p-LAPLACE EQUATIONS

In this paper N-dimensional singular, p-Laplace equations of the following form are considered, where p ≥N, β > 0, and f : [0,∞)×(0,∞)×[0, ∞)→[0,∞) is a continuous function. Some sufficient conditions are obtained for the existence of infinitely many radially positive entire solutions of the equation which are asymptotic to positive constant multiples of |x|(p-N)/(p-1) for p > N or log|x| for N = p as |x|→∞.     

The PC—Based ATLAS Event Filter Prototype：Supervision Design,Implementation and Tests

The studies undertaken to prepare the Technical Design Report of the ATLAS 3^rd Level Trigger(Event Filter)are performed on different prototypes based on different technologies.we present here the most recent results obtained for the supervision of the prototype based on conventional,off-the-shelf PC machines and Java Moblie agent technology.     

MAXIMUM NORM ERROR ESTIMATES OF CROUZEIX-RAVIART NONCONFORMING FINITE ELEMENT APPROXIMATION OF NAVIER-STOKES PROBLEM

1. IntroductionThere are many research works on finite element approximation of Navier-Stokesproblem in the case of lower Reynold number, by using the so-called velocity--pressuremixed by Teman [26], the optimal results were also obtained. The other nonconforming finiteelement schemes for Navie--Stokes problem may be found in [4,8,9,14,15,23,26]. But sofar, maximum norm error estimates for any nonconforming finite element schemes werenot considered.Recently, the quasi--optimal maximum norm …     

MICROSTRUCTURAL CHARACTERIZATION OF SPIN—VALVE MULTILAYERS BY X—RAY ANOMALYOUS DIFFRACTION TECHNIQUE

It is impossible to directly analyze the microstructure of spin-valve multilayers based on Ni,F,Cu and Mn by a conventional X-ray diffraction technique because the lattice parameter and atomic sattering factor sof them are very close.To solve this problem, we use an x-ray anomalous diffraction technique to characterize the microstructures of the [Ni80Fe20/Fe50Mn50]15 and [Ni80Fe20/Cu]15 superlattice systems.The results show that more diffraction peaks and higher internsity in the reflectivety profile are observed when the incident energy is close to the absorption edge of the lighter element(Mn) in [Ni80Fe20/Fe50Mn50]15 multilayer systems and to the absorption edge of the heavier element (Cu) in the [Ni80Fe20/Cu]15 multilayer systems.The interface and periodic structure of [Ni80F20/Fe50Mn50]15 are more perfect than that of the [Ni80Fe20/Cu]15 superlattices.The above results are disussed in this paper.     

Study on mode-filtered light sensor for methane detection

A novel mode-filtered light gas sensor has been reported.It was constructed by inserting an optical fiber deposited by a thin silicone cladding of cryptophane A into a fused-silica capillary.When different concentration of methane gas was introduced to the sensor,the phenomenon that mode-filtered light intensity decreased with the increasing concentration of methane was observed. And a linear relationship was obtained within the methane concentration range of 0.0-16.0%(v/v).The detection limit was 0.06% ...     

RHIC能区Au+Au碰撞中集合径向流的研究

利用相对论量子分子动力学模型RQMD,对RHIC能区s=200A GeV Au+Au碰撞的集体膨胀效应进行了研究,对散射粒子的横质量谱进行了分析.研究表明,在RHIC能区的重离子反应中存在有强的集合径向流.对单粒子谱的拟合结果给出Au+Au的源冻结温度为160MeV,平均径向流速度为0.6c.     

CATALYTIC CRACKING OF LIGHT ALKANES IN THE PRESENCE OF O_2 AND SELECTIVE CONTROL OF OLEFIN PRODUCTS

lntroductionThesmallolefinslikeethylene,propeneandbutenearethec0mmerciallydesirablepetrochemicalfeedstocksandarefoundincreasingusageinchemicalindustry.Theyareusuallyobtainedfromthepyrolysis0fpetroleumhydrocarb0nswithsteaInatveryhightemPeratUreandarealsoavailablefromFCCprocess.TheimProvedFCCcatalystforeIhancingtheolefinproducthasbeenreportedll].However,FCCisalrnostimPossiblefortheshortchainalkanefeedstockscutfrompetroleum0robtuinedfromrefinerygasornatUralgassincecrackingofhydrocarbonsbeco…