In this paper a set of methods identifying minijet from final state particles in the relativistic heavy ion collision events is established and the parameter dependence has been investigated in Au＋Au collisions at √...In this paper a set of methods identifying minijet from final state particles in the relativistic heavy ion collision events is established and the parameter dependence has been investigated in Au＋Au collisions at √s=200 GeV using a multiphase transport model （AMPT）. It is found that the number of minijets reduces with the increasing of collision parameter and raises with the increasing of c.m energy. Furthermore, we analyze the rapidity and momentum distribution inside minijets identified using this method.展开更多
This paper presents a study on ＇hard＇ and ＇soft＇ interactions in ^-pp （pp） collisions using a phenomenological model of HIJING, the jet-cone reconstruction method is employed to select the ＇hard＇ and ＇soft＇ ...This paper presents a study on ＇hard＇ and ＇soft＇ interactions in ^-pp （pp） collisions using a phenomenological model of HIJING, the jet-cone reconstruction method is employed to select the ＇hard＇ and ＇soft＇ event sub-samples from minimum bias events. It is found that the HIJING model can reproduce the energy scaling behaviour of mean transverse momentum （〈PT〉） distributions of charged hadrons versus multiplicity （Nch） in ＇soft＇ events. From the PYTHIA simulation comparing with the HIJING model, the enhancement of the kaon and proton yields from ＇hard＇ interactions comparing with ＇soft＇ interactions is observed to be due to the mini-jets effect. These mechanisms responsible for the increase of charged hadron＇s （PT） are different in ＇soft＇ and ＇hard＇ interactions.展开更多
Based on TOMS total ozone data and SCIAMACHY ozone profile data, climatology of the ozone minihole events over the Tibetan Plateau and ozone vertical structure variations during an ozone mini-hole event in December 20...Based on TOMS total ozone data and SCIAMACHY ozone profile data, climatology of the ozone minihole events over the Tibetan Plateau and ozone vertical structure variations during an ozone mini-hole event in December 2003 are analyzed. The analyses show that before 1990 ozone mini-hole events only occurred in November-December of 1987 but that the number of events increases after 1990. These events only occur from October through February, with maximum occurrence frequency in December. During the event in December 2003, the decrease in total ozone of over 20% is mainly caused by the ozone loss in the upper troposphere and lower stratosphere region due to the horizontal transport of low ozone from the lower latitude subtropics and the uplift of low ozone from the lower troposphere over the Tibetan Plateau.展开更多
An experimental investigation of the jet nanofluids impingement heat transfer characteristics of mini-channel heat sink for cooling computer processing unit of personal computer is performed. The experiments are teste...An experimental investigation of the jet nanofluids impingement heat transfer characteristics of mini-channel heat sink for cooling computer processing unit of personal computer is performed. The experiments are tested under the real personal computer operating conditions: no load and full load conditions. The experiments are performed for the following ranges of the parameters: coolant flow rate varies from 0.008 to 0.020 kg/s, the nozzle diameter is set to 1.00, 1.40, 1.80 mm, the distance nozzle-to-fins tip is 2.00 mm, the channel width of the mini-channel heat sink is 1.00 mm. The nanofluids with suspending of TiO2 particles in base fluid are used as a working fluids. It was observed that the average CPU temperatures obtained from the jet nanofluids impingement cooling system are 3.0%, 6.25% lower than those from the jet liquid impingement and from the conventional liquid cooling systems, respectively. However, this cooling system requires higher energy consumption.展开更多
基金Supported by National Natural Science Foundation of China (10775056)
文摘In this paper a set of methods identifying minijet from final state particles in the relativistic heavy ion collision events is established and the parameter dependence has been investigated in Au＋Au collisions at √s=200 GeV using a multiphase transport model （AMPT）. It is found that the number of minijets reduces with the increasing of collision parameter and raises with the increasing of c.m energy. Furthermore, we analyze the rapidity and momentum distribution inside minijets identified using this method.
基金Project supported by National Natural Science Foundation of China （Grant Nos 10275060 and 10475071）.
文摘This paper presents a study on ＇hard＇ and ＇soft＇ interactions in ^-pp （pp） collisions using a phenomenological model of HIJING, the jet-cone reconstruction method is employed to select the ＇hard＇ and ＇soft＇ event sub-samples from minimum bias events. It is found that the HIJING model can reproduce the energy scaling behaviour of mean transverse momentum （〈PT〉） distributions of charged hadrons versus multiplicity （Nch） in ＇soft＇ events. From the PYTHIA simulation comparing with the HIJING model, the enhancement of the kaon and proton yields from ＇hard＇ interactions comparing with ＇soft＇ interactions is observed to be due to the mini-jets effect. These mechanisms responsible for the increase of charged hadron＇s （PT） are different in ＇soft＇ and ＇hard＇ interactions.
基金supported by theNational Natural Science Foundation of China (NSFC) un-der Grant Nos. 40675021 and 40775030.
文摘Based on TOMS total ozone data and SCIAMACHY ozone profile data, climatology of the ozone minihole events over the Tibetan Plateau and ozone vertical structure variations during an ozone mini-hole event in December 2003 are analyzed. The analyses show that before 1990 ozone mini-hole events only occurred in November-December of 1987 but that the number of events increases after 1990. These events only occur from October through February, with maximum occurrence frequency in December. During the event in December 2003, the decrease in total ozone of over 20% is mainly caused by the ozone loss in the upper troposphere and lower stratosphere region due to the horizontal transport of low ozone from the lower latitude subtropics and the uplift of low ozone from the lower troposphere over the Tibetan Plateau.
文摘An experimental investigation of the jet nanofluids impingement heat transfer characteristics of mini-channel heat sink for cooling computer processing unit of personal computer is performed. The experiments are tested under the real personal computer operating conditions: no load and full load conditions. The experiments are performed for the following ranges of the parameters: coolant flow rate varies from 0.008 to 0.020 kg/s, the nozzle diameter is set to 1.00, 1.40, 1.80 mm, the distance nozzle-to-fins tip is 2.00 mm, the channel width of the mini-channel heat sink is 1.00 mm. The nanofluids with suspending of TiO2 particles in base fluid are used as a working fluids. It was observed that the average CPU temperatures obtained from the jet nanofluids impingement cooling system are 3.0%, 6.25% lower than those from the jet liquid impingement and from the conventional liquid cooling systems, respectively. However, this cooling system requires higher energy consumption.
