Results 141 to 150 of about 10,558 (195)
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Viscosity of refrigerants R12, R113, and R114 and mixtures of R12 + R114 at high pressure
International Journal of Thermophysics, 1989New viscosity measurements for the gaseous and supercritical state of the halogenated hydrocarbons R12, R113, and R114 and binary mixtures of R12 + R114 of different compositions are presented. The measurements were carried out at superheated and supercritical temperatures from 30 to 200° C and in the pressure range from 1 to 80 bar.
H. Nabizadeh, F. Mayinger
exaly +2 more sources
New fluids as substitute refrigerants for R12
Solar Energy Materials and Solar Cells, 1997Abstract The aim of the present study is to suggest two new fluids as alternatives of R12 in a vapour compression cycle. These fluids are the methyl trifluoromethyl ether (E143a) and the hexafluorocyclopropane (C216), which belong to halogenated derivatives of dimethyl ether and cyclopropane, respectively.
T. Rachidi +3 more
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Metastable flow of R12 through capillary tubes
International Journal of Refrigeration, 1990Abstract The metastable flow phenomenon of R12 through two capillary tubes 0.66 and 1.17 mm i.d. and 1.5 m in length was investigated experimentally. The effects of the diameter of the capillary tube, the back pressure, the mass flow-rate and the inlet sub-cooling of the refrigerant on the delay of vaporization of the refrigerant inside the capillary
Sui Lin
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Extensions of r12 corrections to CC2-R12 for excited states
The Journal of Chemical Physics, 2006As known since about two decades, R12 methods, which include terms linear in the interelectronic distance r12 in the wave function, improve substantially the basis set convergence of the ground state correlation energy. In a previous study, however, it was found that the same approach does not give a similar systematic improvement if applied to excited
Christian, Neiss +2 more
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An investigation into the use of R12, R12 mixtures in air conditioners
International Journal of Refrigeration, 1980Abstract An appraisal of the use of mixed refrigerants is presented following an investigation on the performance of a window air conditioner. This system was chosen because the temperature changes are comparatively large. The important results of the study and proposals to reduce power consumption and achieve optimum performance are described.
P.L. Dhar, A.M.Bin Gadhi
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The Journal of Chemical Physics, 2006
Coupled-cluster response theory for vertical excitation energies within the second-order approximate coupled-cluster singles-and-doubles model CC2, including linear-r12 corrections, is derived and implemented for Ansätze 1 and 2 of R12 theory. An orthonormal auxiliary basis set is used for the resolution-of-the-identity approximation in order to ...
Heike, Fliegl +2 more
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Coupled-cluster response theory for vertical excitation energies within the second-order approximate coupled-cluster singles-and-doubles model CC2, including linear-r12 corrections, is derived and implemented for Ansätze 1 and 2 of R12 theory. An orthonormal auxiliary basis set is used for the resolution-of-the-identity approximation in order to ...
Heike, Fliegl +2 more
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Avoiding numerical instabilities in R12 calculations through universal R12 consistent basis sets
Chemical Physics Letters, 2003Abstract We show that the incidental numerical instabilities in explicitly correlated coupled cluster R12 (CC-R12) calculations can be a priori removed by using systematically developed R12 suited basis sets. Those are quite different from basis sets developed for conventional calculations mainly in polarization functions.
Pierre Valiron +2 more
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Quality of service in 3GPP R12 LTE-advanced
IEEE Communications Magazine, 2013Growing demand for mobile data traffic is challenging even the capacities of next generation wireless networks. In response, operators worldwide are expanding and updating their deployment. In turn, 3GPP continues to explore ways to empower operators with features for more capable, economic, and energy-efficient networks.
Najah A. Abu Ali +2 more
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Some investigations of the MP2-R12 method
Theoretica Chimica Acta, 1991The MP2-R12 method was introduced by Kutzelnigg and Klopper to overcome the problem caused by truncation of the one electron basis set in correlation energy calculations at the Moller-Plesset second order level of approximation. Here, we have evaluated the integrals required by their simplest scheme using the Rys-quadrature procedure.
Michael J. Bearpark +3 more
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Replacement of R12 in Refrigeration Systems
1993Three aspects of work relating to the replacement of R12 refrigeration and heat pump applications. In the first, the use of non-azeotropic fluid mixtures in a mixture cascade system is discussed and both theoretical and experimental results are presented.
J. T. McMullan +3 more
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