Graphite is applied to many applications in the field of atomic energy. In the design of nuclear reactors, such as ADS, HTGRs and fusion reactors, graphite is among the primary candidate materials for a reflector zone...Graphite is applied to many applications in the field of atomic energy. In the design of nuclear reactors, such as ADS, HTGRs and fusion reactors, graphite is among the primary candidate materials for a reflector zone to soften the neutron spectrum. Moreover, the accurate prediction of tritium breeding ratio and nuclear heating rate sets the necessity of using adequate nuclear data for carbon since they have strong influence on the feasibility of the overall design of fusion reactors.展开更多
A new concept of the Gravity-driven dense granular flow spallation target for ADS was proposed. The target material is discrete Tungsten-based alloys solid particles. The neutron transport behavior in granular Tungste...A new concept of the Gravity-driven dense granular flow spallation target for ADS was proposed. The target material is discrete Tungsten-based alloys solid particles. The neutron transport behavior in granular Tungsten is very important for the design of spallation target.The neutron transport behavior in granular Tungsten target was studied in detail.展开更多
The design of ADS spallation target requires precise and reliable nuclear data. ADS research team of Chinese Academy of Sciences (CAS) proposed a new concept for a Gravity-driven dense granular flow spallation target[...The design of ADS spallation target requires precise and reliable nuclear data. ADS research team of Chinese Academy of Sciences (CAS) proposed a new concept for a Gravity-driven dense granular flow spallation target[1].The target material is Tungsten-based alloys solid particles. The neutron nuclear data of granular Tungsten is very important for the design of spallation target.展开更多
The Accelerator-Driven Systems (ADS) is mainly used for nuclear transmutation of long-lived fission products, fuel breeding and energy production. China has started to develop the ADS project and is now underway vigor...The Accelerator-Driven Systems (ADS) is mainly used for nuclear transmutation of long-lived fission products, fuel breeding and energy production. China has started to develop the ADS project and is now underway vigorously.The combination of nuclear data with a Monte Carlo transportation code like MCNP-4C is widely applied to design such kind of nuclear engineering facilities. The integral experiment is conducted to benchmark the nuclear data, involved in design calculations, both with regard to the activation and the particle transport behavior.展开更多
According to the interplay model proposed in Ref. [1], an improved model, Collective-thermal Competition(Percolation) Model (CTCPM) is developed. The improvements are made by adding the momentum conservationinto the i...According to the interplay model proposed in Ref. [1], an improved model, Collective-thermal Competition(Percolation) Model (CTCPM) is developed. The improvements are made by adding the momentum conservationinto the interplay of the thermal motion and the collective motion and limiting the emitting system to be finite.For a nuclear system at a thermal equilibrium, the momentum of the thermal motion distributes isotropically in x,y, z directions (z is the beam direction) and make no effect on the flow (Px) in average.展开更多
China has started to develop the Chinese Initiative Accelerator Driven Systems (C-ADS) project which is nowunderway vigorously. This project mainly aims at high radioactive nuclear waste transmutation, fuel breeding a...China has started to develop the Chinese Initiative Accelerator Driven Systems (C-ADS) project which is nowunderway vigorously. This project mainly aims at high radioactive nuclear waste transmutation, fuel breeding andclean energy production. In the design of C-ADS, 1 GeV high intensity proton beam bombards on heavy metalspallation target inside the subcritical reactor, and provides external neutron source for the subcritical reactor. Thecombination of evaluated nuclear data with a Monte Carlo transportation code like MCNP is widely utilized fordesigning such kind of nuclear engineering facilities. However, the transportation codes and evaluated nuclear dataused need to be validated through integral experiments[1?5].展开更多
The combination of nuclear models with a Monte Carlo transportation code like MCNP, GEANT4 and FLUKA,nucleon meson transport codes (NMTC) are widely utilized for designing of Accelerator Driven Systems (ADS).However, ...The combination of nuclear models with a Monte Carlo transportation code like MCNP, GEANT4 and FLUKA,nucleon meson transport codes (NMTC) are widely utilized for designing of Accelerator Driven Systems (ADS).However, the nuclear models embedded into transportation codes need to be validated by experimental measure-ments. A Neutron Time-of-Flight (NTOF) spectrometer, which is based on Heavy Ion Research Facility in Lanzhou(HIRFL), is designed for further investigations of reaction mechanisms and neutron productions of proton inducedspallation reactions related to the ADS project. The NTOF spectrometer is capable of measuring neutrons in awide energy and angular ranges. It consists of a beam pick-up detector and 10 individual neutron detection modules.The schematic view of the NTOF spectrometer is shown in Fig. 1.展开更多
Previous experimental work[1] has shown that a Phase Transition (PT) in C60 multifragmentation induced bynanosecond laser occurs at almost constant temperature covering a wide range of laser fluency. However, up tonow...Previous experimental work[1] has shown that a Phase Transition (PT) in C60 multifragmentation induced bynanosecond laser occurs at almost constant temperature covering a wide range of laser fluency. However, up tonow, to the phase transition occurring in C60 systems much uncertainty remains regarding its nature. In particular,whether it, like those occurring in other finite systems such as nuclei[2], is also related to a liquid-to-gas phasetransition. If so, at the critical temperature, the size distributions of primary intermediate-mass fragments in themultifragmentation regime should obey power law with a particular scaling exponent[3].展开更多
We investigate the neutron induced reactions on gallium sample, and its experimental neutron leakage spectra at the neutron incident energy of 14.8 MeV are comparedwith the Talys1.6[1] calculated results at 60? and1...We investigate the neutron induced reactions on gallium sample, and its experimental neutron leakage spectra at the neutron incident energy of 14.8 MeV are comparedwith the Talys1.6[1] calculated results at 60? and120?. In the Talys code, the neutron-induced reactionis divided in three physical processes, e.g., direct, preequilibriumand compound nucleus reactions. Calculatedtotal neutron leakage energy spectrum and thecontributions from three processes are shown in Fig. 1(a). Natural Ga (60.11% 69Ga and 39.89% 71Ga) sampleswere used in the plots. The calculated total crosssection shows three characteristic features, an elasticpeak, an inelastic peak and a broad bump in the lowenergy side. The elastic and inelastic peaks are generatedby the direct process. The broad bump at thelow energy is dominated by the compound nucleus process.展开更多
In general, the definition of the transverse flow can be classified into the slope flow[1] and the average flow[2]in the certain mid-rapidity region. For a given type of isotope with mass number A, these two definitio...In general, the definition of the transverse flow can be classified into the slope flow[1] and the average flow[2]in the certain mid-rapidity region. For a given type of isotope with mass number A, these two definitions are,respectively, expressed展开更多
Imaging detector is an increasingly popular tool for measuring kinetic energy distributions of photoelectrons orions from photoionization and photodissociation[1;2]. An important advance in imaging is Velocity Map Ima...Imaging detector is an increasingly popular tool for measuring kinetic energy distributions of photoelectrons orions from photoionization and photodissociation[1;2]. An important advance in imaging is Velocity Map Imaging(VMI)[3], where the electron/ion optics consists of a lens, which signicantly reduces the sensitivity of the positionof impact on detector on the position of creation of the ion or electron, while maintaining the dependence of theposition of impact on the initial velocity.展开更多
Zinc is important in reactor to decrease the radiation elds and primary water stress corrosion cracking^([1]).Therapeutic radionuclides ^(64)Cu and^(67)Cu can be potentially produced by neutron induced reactions on zi...Zinc is important in reactor to decrease the radiation elds and primary water stress corrosion cracking^([1]).Therapeutic radionuclides ^(64)Cu and^(67)Cu can be potentially produced by neutron induced reactions on zinc.Light charged particles produced via neutron induced reactions can lead to material damage of reactor and accelerator.展开更多
Effects of cluster correlations on fragments emission in ^(12)C+^(12)C at 50 MeV/u are studied with the antisymmetrized molecular dynamics(AMD)and an extended version of AMD,which has introduced cluster correlation ba...Effects of cluster correlations on fragments emission in ^(12)C+^(12)C at 50 MeV/u are studied with the antisymmetrized molecular dynamics(AMD)and an extended version of AMD,which has introduced cluster correlation based on the original AMD version(AMD-cluster).For the simulations,AMD model contains no effects of cluster correlations.The experimental data are well reproduced by the AMD-cluster calculations for light charged particles with Z≤2(LCPs).The angle distributions of isotopes with Z>2(IMFs)are reproduced reasonably well by the AMD-cluster calculations.But the yields of ^(8)B,^(10)Be,^(10)C and ^(12)C do not improve.展开更多
文摘Graphite is applied to many applications in the field of atomic energy. In the design of nuclear reactors, such as ADS, HTGRs and fusion reactors, graphite is among the primary candidate materials for a reflector zone to soften the neutron spectrum. Moreover, the accurate prediction of tritium breeding ratio and nuclear heating rate sets the necessity of using adequate nuclear data for carbon since they have strong influence on the feasibility of the overall design of fusion reactors.
文摘A new concept of the Gravity-driven dense granular flow spallation target for ADS was proposed. The target material is discrete Tungsten-based alloys solid particles. The neutron transport behavior in granular Tungsten is very important for the design of spallation target.The neutron transport behavior in granular Tungsten target was studied in detail.
文摘The design of ADS spallation target requires precise and reliable nuclear data. ADS research team of Chinese Academy of Sciences (CAS) proposed a new concept for a Gravity-driven dense granular flow spallation target[1].The target material is Tungsten-based alloys solid particles. The neutron nuclear data of granular Tungsten is very important for the design of spallation target.
文摘The Accelerator-Driven Systems (ADS) is mainly used for nuclear transmutation of long-lived fission products, fuel breeding and energy production. China has started to develop the ADS project and is now underway vigorously.The combination of nuclear data with a Monte Carlo transportation code like MCNP-4C is widely applied to design such kind of nuclear engineering facilities. The integral experiment is conducted to benchmark the nuclear data, involved in design calculations, both with regard to the activation and the particle transport behavior.
文摘According to the interplay model proposed in Ref. [1], an improved model, Collective-thermal Competition(Percolation) Model (CTCPM) is developed. The improvements are made by adding the momentum conservationinto the interplay of the thermal motion and the collective motion and limiting the emitting system to be finite.For a nuclear system at a thermal equilibrium, the momentum of the thermal motion distributes isotropically in x,y, z directions (z is the beam direction) and make no effect on the flow (Px) in average.
文摘China has started to develop the Chinese Initiative Accelerator Driven Systems (C-ADS) project which is nowunderway vigorously. This project mainly aims at high radioactive nuclear waste transmutation, fuel breeding andclean energy production. In the design of C-ADS, 1 GeV high intensity proton beam bombards on heavy metalspallation target inside the subcritical reactor, and provides external neutron source for the subcritical reactor. Thecombination of evaluated nuclear data with a Monte Carlo transportation code like MCNP is widely utilized fordesigning such kind of nuclear engineering facilities. However, the transportation codes and evaluated nuclear dataused need to be validated through integral experiments[1?5].
文摘The combination of nuclear models with a Monte Carlo transportation code like MCNP, GEANT4 and FLUKA,nucleon meson transport codes (NMTC) are widely utilized for designing of Accelerator Driven Systems (ADS).However, the nuclear models embedded into transportation codes need to be validated by experimental measure-ments. A Neutron Time-of-Flight (NTOF) spectrometer, which is based on Heavy Ion Research Facility in Lanzhou(HIRFL), is designed for further investigations of reaction mechanisms and neutron productions of proton inducedspallation reactions related to the ADS project. The NTOF spectrometer is capable of measuring neutrons in awide energy and angular ranges. It consists of a beam pick-up detector and 10 individual neutron detection modules.The schematic view of the NTOF spectrometer is shown in Fig. 1.
基金National Natural Science Foundation of China (U1232122 and 10904152).
文摘Previous experimental work[1] has shown that a Phase Transition (PT) in C60 multifragmentation induced bynanosecond laser occurs at almost constant temperature covering a wide range of laser fluency. However, up tonow, to the phase transition occurring in C60 systems much uncertainty remains regarding its nature. In particular,whether it, like those occurring in other finite systems such as nuclei[2], is also related to a liquid-to-gas phasetransition. If so, at the critical temperature, the size distributions of primary intermediate-mass fragments in themultifragmentation regime should obey power law with a particular scaling exponent[3].
文摘We investigate the neutron induced reactions on gallium sample, and its experimental neutron leakage spectra at the neutron incident energy of 14.8 MeV are comparedwith the Talys1.6[1] calculated results at 60? and120?. In the Talys code, the neutron-induced reactionis divided in three physical processes, e.g., direct, preequilibriumand compound nucleus reactions. Calculatedtotal neutron leakage energy spectrum and thecontributions from three processes are shown in Fig. 1(a). Natural Ga (60.11% 69Ga and 39.89% 71Ga) sampleswere used in the plots. The calculated total crosssection shows three characteristic features, an elasticpeak, an inelastic peak and a broad bump in the lowenergy side. The elastic and inelastic peaks are generatedby the direct process. The broad bump at thelow energy is dominated by the compound nucleus process.
文摘In general, the definition of the transverse flow can be classified into the slope flow[1] and the average flow[2]in the certain mid-rapidity region. For a given type of isotope with mass number A, these two definitions are,respectively, expressed
基金National Natural Science Foundation of China (U1232122, 10904152)
文摘Imaging detector is an increasingly popular tool for measuring kinetic energy distributions of photoelectrons orions from photoionization and photodissociation[1;2]. An important advance in imaging is Velocity Map Imaging(VMI)[3], where the electron/ion optics consists of a lens, which signicantly reduces the sensitivity of the positionof impact on detector on the position of creation of the ion or electron, while maintaining the dependence of theposition of impact on the initial velocity.
文摘Zinc is important in reactor to decrease the radiation elds and primary water stress corrosion cracking^([1]).Therapeutic radionuclides ^(64)Cu and^(67)Cu can be potentially produced by neutron induced reactions on zinc.Light charged particles produced via neutron induced reactions can lead to material damage of reactor and accelerator.
文摘Effects of cluster correlations on fragments emission in ^(12)C+^(12)C at 50 MeV/u are studied with the antisymmetrized molecular dynamics(AMD)and an extended version of AMD,which has introduced cluster correlation based on the original AMD version(AMD-cluster).For the simulations,AMD model contains no effects of cluster correlations.The experimental data are well reproduced by the AMD-cluster calculations for light charged particles with Z≤2(LCPs).The angle distributions of isotopes with Z>2(IMFs)are reproduced reasonably well by the AMD-cluster calculations.But the yields of ^(8)B,^(10)Be,^(10)C and ^(12)C do not improve.
