1,062 research outputs found

    Estimate of the rate of charged particle vertical transfer in the outer part of the ionosphere F2-region

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    Estimates of charged particle vertical transfer rates in F 2 regio

    Higher Twist Effects in Proton-Proton Collisions

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    In this article, we investigate the contribution of the high twist Feynman diagrams to the large-pTp_T pion production cross section in proton-proton collisions and we present the general formulae for the high and leading twist differential cross sections. The pion wave function where two non-trivial Gegenbauer coefficients a2a_2 and a4a_4 have been extracted from the CLEO data, two other pion model wave functions, P2P_2, P3P_3, the asymptotic and the Chernyak-Zhitnitsky wave functions are used in the calculations. The results of all the calculations reveal that the high twist cross sections, the ratios RR, rr, the dependence transverse momentum pTp_T and the rapidity yy of pion in the ΦCLEO(x,Q2)\Phi_{CLEO}(x,Q^2) wave function case is very close to the Φasy(x)\Phi_{asy}(x) asymptotic wave function case. It is shown that the high twist contribution to the cross section depends on the choice of the meson wave functions.Comment: 28 pages 18 figures RevTex

    Investigation of the nuetralino pair production at LHC

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    In this article, we investigate the Drell-Yan process of the light neutralino pair χ~i0χ~j0\widetilde{\chi}_{i}^{0}\widetilde{\chi}_{j}^{0} (i,j=1,2i,j=1,2) productions at proton-proton collisions and we present the general formulate for the differential cross sections. We conduct an extensive examination of the dependence of the total cross section of the subprocesses qqˉ→χ~i0χ~j0q \bar q \to \widetilde \chi_{i}^{0}\widetilde\chi_{j}^{0} on the beam energy, on the mass of the squarks and also on the M2M_2 gaugino for the three extremely different scenarios. For all three cases, the outcomes are as follows. The dependence of the total cross section of the subprocesses qqˉ→χ~i0χ~j0q \bar q \to \widetilde \chi_{i}^{0} \widetilde \chi_{j}^{0} on the beam energy is dominated by one of the subprocesses, qqˉ→χ~10χ~20q \bar q \to \widetilde \chi_{1}^{0} \widetilde \chi_{2}^{0}. On the other hand, the dependence of the total cross section of the subprocesses qqˉ→χ~i0χ~j0q \bar q \to \widetilde \chi_{i}^{0} \widetilde \chi_{j}^{0} on the mass of the squarks is dominated by one of the subprocesses, qqˉ→χ~10χ~20q \bar q \to \widetilde \chi_{1}^{0} \widetilde \chi_{2}^{0}. We derive there from that our findings may lead to new insights relating to experimental investigations and these dependencies may be used as bases of an experimental research for the neutralino pair at LHC.Comment: 38pp, 22 figures, ReVTeX4, (Baku State University, Azerbaijan, and Erciyes University, Kayseri, Turkey

    Thermocatalytic CO2-Free Production of Hydrogen and Carbon from Hydrocarbons.

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    This invention relates to a novel process for sustainable CO.sub.2-free production of hydrogen and carbon by thermocatalytic decomposition (or dissociation, pyrolysis, cracking) of hydrocarbon fuels over carbon-based catalysts in the absence of air and/or water. The process is applicable to any hydrocarbon fuel, including sulfurous fuels. Combination of a catalytic reactor with a gas separation unit allows to produce high purity hydrogen (at least, 99.0 v%) completely free of carbon oxides. In a preferred embodiment, sustainable continuous production of hydrogen and carbon is achieved by both internal and external activation of carbon catalysts. Internal activation of carbon catalyst is accomplished by recycling of hydrogen-depleted gas containing unsaturated and aromatic hydrocarbons back to the reactor. External activation can be achieved via surface gasification of carbon catalysts by hot combustion gases during catalyst heating. The process can conveniently be integrated with any

    Thermocatalytic CO2-Free Production of Hydrogen and Carbon from Hydrocarbons. DIV

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    A novel process and apparatus are disclosed for sustainable CO.sub.2-free production of hydrogen and carbon by thermocatalytic decomposition (dissociation, pyrolysis, cracking) of hydrocarbon fuels over carbon-based catalysts in the absence of air and/or water. The apparatus and thermocatalytic process improve the activity and stability of carbon catalysts during the thermocatalytic process and produce both high purity hydrogen (at least, 99.0 volume %) and carbon, from any hydrocarbon fuel, including sulfurous fuels. In a preferred embodiment, production of hydrogen and carbon is achieved by both internal and external activation of carbon catalysts. Internal activation of carbon catalyst is accomplished by recycling of hydrogen-depleted gas containing unsaturated and aromatic hydrocarbons back to the reactor. External activation of the catalyst can be achieved via surface gasification with hot combustion gases during catalyst heating. The process and apparatus can be conveniently int

    Mobile Car Rental System

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    This paper gives an overview of "M-commerce" approaches that allow car-rental companies in Malaysia to upgrade and optimize their business processes. First it addresses issues that are found in traditional car rental sector like slow turnaround and large amount of time needed to do reservation. Later it describes how these issues are solved using new mobile technology that provides true mobility, instant information and better customer service over traditional manual and wired online car rental business. To achieve a positive result author applied prototyping methodology tliroughout this project that quickly provides a system for the users to interact with. The successful result in the end of this project proved that mobile technology can easily and efficiently be applied to businesses that provide services, such as car rental companies. However drawbacks were also found, which are small memory, limited functionality and limited content of mobile devices that can be eliminated in future with new developments of wireless devices and communication infrastructures. Finally this project paper highlights the result of research and development activity that was carried out to develop new system, which will benefit car-rental companies in a way increasing number of customers, reducing operating cost and finally making them more competitive in our rushing world

    Filamentous Carbon Particles for Cleaning Oil Spills and Method of production. DIV.B

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    A compact hydrogen generator is coupled to or integrated with a fuel cell for portable power applications. Hydrogen is produced via thermocatalytic decomposition (cracking, pyrolysis) of hydrocarbon fuels in oxidant-free environment. The apparatus can utilize a variety of hydrocarbon fuels, including natural gas, propane, gasoline, kerosene, diesel fuel, crude oil (including sulfurous fuels). The hydrogen-rich gas produced is free of carbon oxides or other reactive impurities, so it could be directly fed to any type of a fuel cell. The catalysts for hydrogen production in the apparatus are carbon-based or metal-based materials and doped if necessary, with a sulfur-capturing agent. Additionally disclosed are two novel processes for the production of two types of carbon filaments, and a novel filamentous carbon product. The hydrogen generator can be conveniently integrated with high temperature fuel cells to produce an efficient and self-contained source of electrical power

    Shot noise of Coulomb drag current

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    We work out a theory of shot noise in a special case. This is a noise of the Coulomb drag current excited under the ballistic transport regime in a one-dimensional nanowire by a ballistic non-Ohmic current in a nearby parallel nanowire. We predict sharp oscillation of the noise power as a function of gate voltage or the chemical potential of electrons. We also study dependence of the noise on the voltage V across the driving wire. For relatively large values of V the noise power is proportional to V^2.Comment: 9 pages, 2 figure
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