2023 Vol. 40, No. 2
Display Method:
2023, 40(2): 141-180.
doi: 10.11804/NuclPhysRev.40.2022098
Abstract:
The nuclear mass(or binding energy) and charge radius are fundamental physical quantities of an atomic nucleus, which can provide important information for nuclear physics and astrophysics. This paper discusses the systematics of nuclear mass and its related physical quantities(such as neutron-proton interaction, pairing interaction, separation energy, α-decay energy and Coulomb energy), as well as nuclear charge radius and so on. These systematics are not only practical methods for predicting unknown physical quantities such as nuclear masses and charge radii with high precision, but also provide effective constraints on the coefficients of nuclear symmetry energy and Wigner energy, and give a simple way to study the evolution of collective motion of low-lying states of nuclei. As a Supplemental Material of this paper(see Science Data Bank), a TABLE including predicted physical quantities such as atomic mass excesses(or binding energies) and nuclear charge radii is provided.
The nuclear mass(or binding energy) and charge radius are fundamental physical quantities of an atomic nucleus, which can provide important information for nuclear physics and astrophysics. This paper discusses the systematics of nuclear mass and its related physical quantities(such as neutron-proton interaction, pairing interaction, separation energy, α-decay energy and Coulomb energy), as well as nuclear charge radius and so on. These systematics are not only practical methods for predicting unknown physical quantities such as nuclear masses and charge radii with high precision, but also provide effective constraints on the coefficients of nuclear symmetry energy and Wigner energy, and give a simple way to study the evolution of collective motion of low-lying states of nuclei. As a Supplemental Material of this paper(see Science Data Bank), a TABLE including predicted physical quantities such as atomic mass excesses(or binding energies) and nuclear charge radii is provided.
2023, 40(2): 181-187.
doi: 10.11804/NuclPhysRev.40.2022078
Abstract:
Storage-ring-based isochronous mass spectrometry(IMS) is an effective tool for mass measurements of nuclei far from stability line. However, in the mass measurements of neutron-deficient nuclei with conventional IMS, systematic deviation of mass determination was observed when nuclei with\begin{document}$T_z^{}=-1/2$\end{document} ![]()
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Storage-ring-based isochronous mass spectrometry(IMS) is an effective tool for mass measurements of nuclei far from stability line. However, in the mass measurements of neutron-deficient nuclei with conventional IMS, systematic deviation of mass determination was observed when nuclei with
2023, 40(2): 188-192.
doi: 10.11804/NuclPhysRev.40.2023089
Abstract:
The study of the exotic structure of nuclei in the island of inversion has always been a hot topic in modern nuclear physics. In this paper, we apply the Complex Momentum Representation(CMR) method to study the resonant states of nuclei. We calculate the single particle bound and resonant energies of 33Mg and their variation with the deformation parameter β2. The occupancy probabilities of the main configurations are tested at the energy level occupied by the last valence neutron and the radial density distributions are calculated. The results show that the ground state of 33Mg has undergone a p-f inversion of the single particle level, and its last valence neutron occupies the intruder energy level. Meanwhile, the deformation range of 33Mg is about 0.49≤β2≤0.55, which is similar to the deformation values of isotopes around 33Mg.
The study of the exotic structure of nuclei in the island of inversion has always been a hot topic in modern nuclear physics. In this paper, we apply the Complex Momentum Representation(CMR) method to study the resonant states of nuclei. We calculate the single particle bound and resonant energies of 33Mg and their variation with the deformation parameter β2. The occupancy probabilities of the main configurations are tested at the energy level occupied by the last valence neutron and the radial density distributions are calculated. The results show that the ground state of 33Mg has undergone a p-f inversion of the single particle level, and its last valence neutron occupies the intruder energy level. Meanwhile, the deformation range of 33Mg is about 0.49≤β2≤0.55, which is similar to the deformation values of isotopes around 33Mg.
2023, 40(2): 193-197.
doi: 10.11804/NuclPhysRev.40.2023021
Abstract:
Lifetimes of nuclear excited states are related to its internal structure, and considered as one of most important values in the nuclear property studies. In this paper, we report the first lifetime measurements of nuclear excited states at the HIRFL facility via Doppler Shift Attenuation Method(DSAM). The excited states of\begin{document}$_{}^{46}{\rm{Ti}}$\end{document} ![]()
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Lifetimes of nuclear excited states are related to its internal structure, and considered as one of most important values in the nuclear property studies. In this paper, we report the first lifetime measurements of nuclear excited states at the HIRFL facility via Doppler Shift Attenuation Method(DSAM). The excited states of
2023, 40(2): 198-206.
doi: 10.11804/NuclPhysRev.40.2022094
Abstract:
The study of glueballs is an important topic in hadron physics, and the search for glueball states is one of the major goal of the Beijing Spectrometer III(BESIII) experiment. Lattice quantum chromodynamics, as a first-principle approach to examine the non-perturbative characteristics of the strong interaction, is an essential theoretical tool to investigate the glueball problem. Recent development of lattice studies on glueballs and possible experimental candidates are reviewed in this article. In addition, the topological charge density of the gauge field can be used as an interpolation field operator to study the properties of pure-gauge pseudoscalar glueball, but only the contributions of the light pseudoscalar mesons\begin{document}$\eta$\end{document} ![]()
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The study of glueballs is an important topic in hadron physics, and the search for glueball states is one of the major goal of the Beijing Spectrometer III(BESIII) experiment. Lattice quantum chromodynamics, as a first-principle approach to examine the non-perturbative characteristics of the strong interaction, is an essential theoretical tool to investigate the glueball problem. Recent development of lattice studies on glueballs and possible experimental candidates are reviewed in this article. In addition, the topological charge density of the gauge field can be used as an interpolation field operator to study the properties of pure-gauge pseudoscalar glueball, but only the contributions of the light pseudoscalar mesons
2023, 40(2): 207-213.
doi: 10.11804/NuclPhysRev.40.2022050
Abstract:
The 300 MeV proton and heavy ion accelerator is an important component of the SESRI(Space Environment Simulation and Research Infrastructure), and the study on slow extraction dynamics is the key part of the accelerator. The third order resonance and RF-Knockout(RF-KO) scheme is adopted to provide quasi-continuous beam in 2~8 s for slow extraction system. 3-bump are used to adjust the spiral step and extraction angle at the electrostatic septum. However, the horizontal tune can be reduced due to the bump orbit, and the stable area in the phase space is shrunk during the extraction flattop. Simulation results show that the bump orbit produced in the dipole and sextupole magnet will reduce the horizontal tune, and a large number of particles are extracted at the initial extraction stage. Therefore, the spill structure should be analyzed and optimized based on the self-written particle tracking program SESP. The extracted beam uniformity is improved by modulating the amplitude of the extraction exciter.
The 300 MeV proton and heavy ion accelerator is an important component of the SESRI(Space Environment Simulation and Research Infrastructure), and the study on slow extraction dynamics is the key part of the accelerator. The third order resonance and RF-Knockout(RF-KO) scheme is adopted to provide quasi-continuous beam in 2~8 s for slow extraction system. 3-bump are used to adjust the spiral step and extraction angle at the electrostatic septum. However, the horizontal tune can be reduced due to the bump orbit, and the stable area in the phase space is shrunk during the extraction flattop. Simulation results show that the bump orbit produced in the dipole and sextupole magnet will reduce the horizontal tune, and a large number of particles are extracted at the initial extraction stage. Therefore, the spill structure should be analyzed and optimized based on the self-written particle tracking program SESP. The extracted beam uniformity is improved by modulating the amplitude of the extraction exciter.
2023, 40(2): 214-220.
doi: 10.11804/NuclPhysRev.40.2022064
Abstract:
The China Spallation Neutron Source(CSNS) has experienced a growing demand for increased beam power, necessitating the replacement of their previous Panning H-ion source with an external antenna RF driven H-ion source. This paper outlines the design and implementation of the control system for this new ion source based on EPICS and PLC. To ensure a stable and reliable operation, solutions were developed to optimize to optimize electromagnetic interference and prevent equipment damage caused by high voltage platform ignition. Additionally, operational assistance programs were designed to improve the long-term stability of the ion source. The control system has been successfully implemented, it has been stable and reliable, providing strong support for the efficient operation of the ion source.
The China Spallation Neutron Source(CSNS) has experienced a growing demand for increased beam power, necessitating the replacement of their previous Panning H-ion source with an external antenna RF driven H-ion source. This paper outlines the design and implementation of the control system for this new ion source based on EPICS and PLC. To ensure a stable and reliable operation, solutions were developed to optimize to optimize electromagnetic interference and prevent equipment damage caused by high voltage platform ignition. Additionally, operational assistance programs were designed to improve the long-term stability of the ion source. The control system has been successfully implemented, it has been stable and reliable, providing strong support for the efficient operation of the ion source.
2023, 40(2): 221-228.
doi: 10.11804/NuclPhysRev.40.2022035
Abstract:
Aiming at the requirement for cosmic ray detection in Imaging Atmospheric Cherenkov Telescopes(IACT) using silicon photomultiplier(SiPM) detectors, a prototype of readout electronics is designed based on waveform digitization using the Switched Capacitor Array(SCA) ASIC. The prototype is able to read out SiPM detector signals with a wide dynamic range and then calculate the time and charge information of the input signal. The design scheme and structure of the readout electronics prototype are presented in this paper, and a series of tests are conducted to verify its performance. The preliminary results show that the time resolution of the readout system prototype is better than 800 ps RMS within the full dynamic range. The charge resolution is better than 30% at 5 P.E. and is better than 3% at 8 000 P.E.. The test results indicate that the readout system prototype meets the design requirements.
Aiming at the requirement for cosmic ray detection in Imaging Atmospheric Cherenkov Telescopes(IACT) using silicon photomultiplier(SiPM) detectors, a prototype of readout electronics is designed based on waveform digitization using the Switched Capacitor Array(SCA) ASIC. The prototype is able to read out SiPM detector signals with a wide dynamic range and then calculate the time and charge information of the input signal. The design scheme and structure of the readout electronics prototype are presented in this paper, and a series of tests are conducted to verify its performance. The preliminary results show that the time resolution of the readout system prototype is better than 800 ps RMS within the full dynamic range. The charge resolution is better than 30% at 5 P.E. and is better than 3% at 8 000 P.E.. The test results indicate that the readout system prototype meets the design requirements.
2023, 40(2): 229-236.
doi: 10.11804/NuclPhysRev.40.2022058
Abstract:
China Space X-Ray Polarization Detection System(CXPD) is dedicated to detecting space X-ray polarization, energy spectrum and other information for understanding astrophysical phenomena. In order to meet the storage requirements of small satellite payloads with strong security, low power consumption and low cost, this paper selects embedded multimedia memory cards with functions of error checking and correction, power-down saving and bad block management as storage media. For the power-up operation of satellite payloads in the special environment of space and the data throughput requirements of satellite payload devices, combined with the eMMC5.0 protocol, this paper studies an on-satellite storage system based on field-programmable gate array(FPGA) control. The system can operate stably in high and low temperature test tests, vibration tests and long time alpha source irradiation tests.
China Space X-Ray Polarization Detection System(CXPD) is dedicated to detecting space X-ray polarization, energy spectrum and other information for understanding astrophysical phenomena. In order to meet the storage requirements of small satellite payloads with strong security, low power consumption and low cost, this paper selects embedded multimedia memory cards with functions of error checking and correction, power-down saving and bad block management as storage media. For the power-up operation of satellite payloads in the special environment of space and the data throughput requirements of satellite payload devices, combined with the eMMC5.0 protocol, this paper studies an on-satellite storage system based on field-programmable gate array(FPGA) control. The system can operate stably in high and low temperature test tests, vibration tests and long time alpha source irradiation tests.
2023, 40(2): 237-243.
doi: 10.11804/NuclPhysRev.40.2022092
Abstract:
Waveform digitization technology based on Switched Capacitor Array(SCA) is one of the important development fields of front-end readout electronics for future physical experiment facilities. In this paper, an ultra-high-speed waveform digital data acquisition circuit based on SCA chip DRS4(Domino Ring Sampler 4) is designed. A single channel of the DRS4 can sample the full waveform of the detector output signal at a sampling rate of up to 5 GHz. The circuit is mainly composed of analog conditioning circuit, a DRS4 circuit, ADC(Analog-to-Digital Converter) circuit, FPGA(Field-Programmable Gate Array), DAC (Digital-to-Analog Converter) circuit, a trigger circuit, an interface circuit, etc. Performance tests show that the circuit's noise is less than 0.5 mV, and the Integral Non-Linearity (INL) is better than 1%. In addition, the analog input bandwidth of this circuit is very high, the sampling rate is adjustable from 700 MHz to 5 GHz, and it has good nonlinearity. Therefore, the data acquisition circuit is versatile and suitable for detector readout in various physical experiment facilities.
Waveform digitization technology based on Switched Capacitor Array(SCA) is one of the important development fields of front-end readout electronics for future physical experiment facilities. In this paper, an ultra-high-speed waveform digital data acquisition circuit based on SCA chip DRS4(Domino Ring Sampler 4) is designed. A single channel of the DRS4 can sample the full waveform of the detector output signal at a sampling rate of up to 5 GHz. The circuit is mainly composed of analog conditioning circuit, a DRS4 circuit, ADC(Analog-to-Digital Converter) circuit, FPGA(Field-Programmable Gate Array), DAC (Digital-to-Analog Converter) circuit, a trigger circuit, an interface circuit, etc. Performance tests show that the circuit's noise is less than 0.5 mV, and the Integral Non-Linearity (INL) is better than 1%. In addition, the analog input bandwidth of this circuit is very high, the sampling rate is adjustable from 700 MHz to 5 GHz, and it has good nonlinearity. Therefore, the data acquisition circuit is versatile and suitable for detector readout in various physical experiment facilities.
2023, 40(2): 244-250.
doi: 10.11804/NuclPhysRev.40.2022083
Abstract:
The detection system designed in this paper is a set of high-efficiency detector system based on the research requirements of the Radioactive Ion Beams physics and the Radioactive Ion Beam Line in Lanzhou(RIBLL) at the Heavy Ion Research Facility in Lanzhou(HIRFL). The detector system consists of six sets of telescopes, each composed of a three-layer structure DSSD+PSD+CSI(Tl). After using Geant4 simulation to obtain the geometric efficiency, the best design of the detection system is given. Then the elastic scattering and breakup reactions of\begin{document}$^{7}\rm{Be}$\end{document} ![]()
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The detection system designed in this paper is a set of high-efficiency detector system based on the research requirements of the Radioactive Ion Beams physics and the Radioactive Ion Beam Line in Lanzhou(RIBLL) at the Heavy Ion Research Facility in Lanzhou(HIRFL). The detector system consists of six sets of telescopes, each composed of a three-layer structure DSSD+PSD+CSI(Tl). After using Geant4 simulation to obtain the geometric efficiency, the best design of the detection system is given. Then the elastic scattering and breakup reactions of
2023, 40(2): 251-256.
doi: 10.11804/NuclPhysRev.40.2022072
Abstract:
Thermal neutron radiography is a powerful nondestructive detecting technique as an important complement to X-ray radiography. The miniaturized thermal neutron radiography system holds great potential in research and industrial applications. Based on the compact D-D neutron generator, a neutron moderator-collimator for thermal neutron radiography was designed and simulated by using Monte Carlo N-Particle Transport Code(MCNP-4C) to track neutrons and γ-rays. The aspect ratio of the moderator-collimator was about 3.58. The simulation results showed that the thermal neutron flux rate could reach and exceed 103 n/(cm2 · s) in the sample plane when the neutron yield of D-D neutron generator is greater than 5×108 n/s. The proportion of thermal neutron in the collimated neutron beam was found to be over 74%. In a irradiation field with a diameter of 70 mm, the non-uniformity of thermal neutron flux was kept at 7.3%, which meets the imaging criteria of thermal neutron radiography.
Thermal neutron radiography is a powerful nondestructive detecting technique as an important complement to X-ray radiography. The miniaturized thermal neutron radiography system holds great potential in research and industrial applications. Based on the compact D-D neutron generator, a neutron moderator-collimator for thermal neutron radiography was designed and simulated by using Monte Carlo N-Particle Transport Code(MCNP-4C) to track neutrons and γ-rays. The aspect ratio of the moderator-collimator was about 3.58. The simulation results showed that the thermal neutron flux rate could reach and exceed 103 n/(cm2 · s) in the sample plane when the neutron yield of D-D neutron generator is greater than 5×108 n/s. The proportion of thermal neutron in the collimated neutron beam was found to be over 74%. In a irradiation field with a diameter of 70 mm, the non-uniformity of thermal neutron flux was kept at 7.3%, which meets the imaging criteria of thermal neutron radiography.
2023, 40(2): 257-263.
doi: 10.11804/NuclPhysRev.40.2022082
Abstract:
The Accelerator Mass Spectrometry System of Guangxi Normal University(GXNU-AMS) was successfully installed and operated in 2017. It is the first homemade single-stage AMS system facility and one of the lowest-energy AMS systems in China. The system adopts 150 kV terminal voltage, helium stripping, and +1 charge state in measurements. During several years of operation, its performance has been improved continuously. The measured abundance sensitivity of 14C and 3H has reached (3.14±0.05)×10−15 and (1.23±0.17)×10−16, respectively, and the application research has been carried out in multidisciplinary field. The performance characteristics, operation, and application of AMS are briefly introduced to provide experimental data for the miniaturization and industrialization of AMS in China and to provide technical tools for the application research of low-energy AMS in nuclear physics, geological science, environmental science, and biomedicine.
The Accelerator Mass Spectrometry System of Guangxi Normal University(GXNU-AMS) was successfully installed and operated in 2017. It is the first homemade single-stage AMS system facility and one of the lowest-energy AMS systems in China. The system adopts 150 kV terminal voltage, helium stripping, and +1 charge state in measurements. During several years of operation, its performance has been improved continuously. The measured abundance sensitivity of 14C and 3H has reached (3.14±0.05)×10−15 and (1.23±0.17)×10−16, respectively, and the application research has been carried out in multidisciplinary field. The performance characteristics, operation, and application of AMS are briefly introduced to provide experimental data for the miniaturization and industrialization of AMS in China and to provide technical tools for the application research of low-energy AMS in nuclear physics, geological science, environmental science, and biomedicine.
2023, 40(2): 264-272.
doi: 10.11804/NuclPhysRev.40.2022028
Abstract:
The components of Chinese medicine water extract are complex. With the development of traditional Chinese medicine pharmacy, it is urgent to establish a simple and effective separation and purification method for traditional Chinese medicine. Membrane separation technology, as a simple, direct and efficient material separation method, is widely used in the separation and purification of traditional Chinese medicine because of its low energy consumption and no secondary pollution. Using the ion-track etched membrane with different pore diameters to filter the Chinese medicine water extract in multiple steps, and characterizing the filtrate. The impurities above 1 μm can be removed through microfiltration without changing the properties of water extract. Besides, the proteins and starches can also be removed through ultrafiltration. After modification, the active components of traditional Chinese medicine, like paeoniflorin and chlorogenic acid, can be separated by the ion-track etched membrane. The results show that the ion-track etched membrane can be applied to the process of separation and purification of Chinese medicine water extract, which proves that the ion-track etched membrane can be used for the separation and purification of Chinese medicine water extract.
The components of Chinese medicine water extract are complex. With the development of traditional Chinese medicine pharmacy, it is urgent to establish a simple and effective separation and purification method for traditional Chinese medicine. Membrane separation technology, as a simple, direct and efficient material separation method, is widely used in the separation and purification of traditional Chinese medicine because of its low energy consumption and no secondary pollution. Using the ion-track etched membrane with different pore diameters to filter the Chinese medicine water extract in multiple steps, and characterizing the filtrate. The impurities above 1 μm can be removed through microfiltration without changing the properties of water extract. Besides, the proteins and starches can also be removed through ultrafiltration. After modification, the active components of traditional Chinese medicine, like paeoniflorin and chlorogenic acid, can be separated by the ion-track etched membrane. The results show that the ion-track etched membrane can be applied to the process of separation and purification of Chinese medicine water extract, which proves that the ion-track etched membrane can be used for the separation and purification of Chinese medicine water extract.
2023, 40(2): 273-279.
doi: 10.11804/NuclPhysRev.40.2022055
Abstract:
Due to the limited irradiation zone, development of small-scale test technology is of significant importance for the investigation of irradiation damage in nuclear materials. Micro-indentation tests and small punch tests(SPT) can efficiently evaluate irradiation hardening and embrittlement. However, the influence of the introduced indents by the micro-indentation tests to the SPT investigation need to be clarified and investigated. In the present study, the A508-3, a Chinese reactor pressure vessel(RPV) steel, and its model alloy (Fe-1.35Mn-0.75Ni) were used to investigate the effect of arbitrarily introduced indents on the SPT. Firstly, both micro-indentation tests and SPT indicate that hardness of A508-3 is significantly greater than the model alloy, accompanied by improved ductility. Electron backscattered diffraction(EBSD) results indicate that a quasi-uniform distribution of grains was observed in both specimens and the grains in A508-3 were obviously smaller than the model alloy. The strengthening of A508-3 was mainly ascribed to the refined grain strengthening and the solution strengthening. The improved ductility was possibly due to the increasing grain numbers or the density of grain boundaries. Secondly, SPT results indicate that, the obtained maximum load, Pmax was obviously influenced by the introduced indents in softer specimen (the model alloy). The obtained ductility was hardly influenced by the introduced indents. For the practical materials, the introduced indents are expected to have minor influence on the data obtained by SPT.
Due to the limited irradiation zone, development of small-scale test technology is of significant importance for the investigation of irradiation damage in nuclear materials. Micro-indentation tests and small punch tests(SPT) can efficiently evaluate irradiation hardening and embrittlement. However, the influence of the introduced indents by the micro-indentation tests to the SPT investigation need to be clarified and investigated. In the present study, the A508-3, a Chinese reactor pressure vessel(RPV) steel, and its model alloy (Fe-1.35Mn-0.75Ni) were used to investigate the effect of arbitrarily introduced indents on the SPT. Firstly, both micro-indentation tests and SPT indicate that hardness of A508-3 is significantly greater than the model alloy, accompanied by improved ductility. Electron backscattered diffraction(EBSD) results indicate that a quasi-uniform distribution of grains was observed in both specimens and the grains in A508-3 were obviously smaller than the model alloy. The strengthening of A508-3 was mainly ascribed to the refined grain strengthening and the solution strengthening. The improved ductility was possibly due to the increasing grain numbers or the density of grain boundaries. Secondly, SPT results indicate that, the obtained maximum load, Pmax was obviously influenced by the introduced indents in softer specimen (the model alloy). The obtained ductility was hardly influenced by the introduced indents. For the practical materials, the introduced indents are expected to have minor influence on the data obtained by SPT.
2023, 40(2): 280-286.
doi: 10.11804/NuclPhysRev.40.2022060
Abstract:
DNA damage response (DDR) is one of the main mechanisms, by which life counters against exogenous and endogenous oxidative stress induced DNA damage. In an organism, the DDR in different cells and tissues has various levels of activation. . Using the model organism Caenorhabditis elegans as experimental objects, we constructed a transgenic line for the pharynx-specific expression of hus-1 gene, upstream of the DDR pathway, and then introduced into hus-1 mutation background, generating DDR pharynx-specific rescue lines BPL1121, BPL1122 and BPL1123 . The experimental system was used to detect the effect of DDR pharynx rescue on the embryos lethality of γ radiation induced and investigate the effects of heterogeneous activation of DDR on radiation biological effects and its underlying mechanisms. Results showed that the embryonic lethality of irradiated BPL1121 worms increased from 24.72 ± 1.77 to 42.66 ± 1.18 (P < 0.01) compared with hus-1 mutant worms, this enhancement continued up to the intact F1 progeny of non-irradiated worms (P < 0.01), although F2 progeny return to background levels (P > 0.05). The insulin-like pathway in nematodes is closely related to the growth, development and reproduction behaviors of nematodes, and daf-2 is a key gene in this signaling pathway. Introducing BPL1121 into the background of daf-2 mutation, it was found that DAF-2 functional loss significantly inhibited the embryonic radiation lethality of BPL1121 worms. The heterogeneous activation of DDR in pharynx increases the radiation sensitivity of germ cells, and the insulin-like pathway participates in the remote regulation of pharyngeal DDR to radio-sensitivity of germ cells.
DNA damage response (DDR) is one of the main mechanisms, by which life counters against exogenous and endogenous oxidative stress induced DNA damage. In an organism, the DDR in different cells and tissues has various levels of activation. . Using the model organism Caenorhabditis elegans as experimental objects, we constructed a transgenic line for the pharynx-specific expression of hus-1 gene, upstream of the DDR pathway, and then introduced into hus-1 mutation background, generating DDR pharynx-specific rescue lines BPL1121, BPL1122 and BPL1123 . The experimental system was used to detect the effect of DDR pharynx rescue on the embryos lethality of γ radiation induced and investigate the effects of heterogeneous activation of DDR on radiation biological effects and its underlying mechanisms. Results showed that the embryonic lethality of irradiated BPL1121 worms increased from 24.72 ± 1.77 to 42.66 ± 1.18 (P < 0.01) compared with hus-1 mutant worms, this enhancement continued up to the intact F1 progeny of non-irradiated worms (P < 0.01), although F2 progeny return to background levels (P > 0.05). The insulin-like pathway in nematodes is closely related to the growth, development and reproduction behaviors of nematodes, and daf-2 is a key gene in this signaling pathway. Introducing BPL1121 into the background of daf-2 mutation, it was found that DAF-2 functional loss significantly inhibited the embryonic radiation lethality of BPL1121 worms. The heterogeneous activation of DDR in pharynx increases the radiation sensitivity of germ cells, and the insulin-like pathway participates in the remote regulation of pharyngeal DDR to radio-sensitivity of germ cells.
2023, 40(2): 287-293.
doi: 10.11804/NuclPhysRev.40.2022063
Abstract:
Comparative analysis of the dosimetric differences between Chinese-produced heavy ion accelerator uniform scanning and photon intensity-modulated radiotherapy(IMRT) treatment plans in the treatment of skull base malignancies. A retrospective analysis of the treatment plans for 8 patients with skull base malignancies treated with the domestic heavy ion equipment (Heavy Ion Medical Machine, HIMM) using uniform scanning, including 7 chordoma and 1 chondrosarcoma. Carbon ion radiotherapy(CIRT) plans were designed using the ciPlan planning system (V1.0) from Lanzhou Kejintaiji Company, with a prescription dose of 57.6~60.8 Gy (RBE) in the planning target volume, delivered in 16 fractions of 3.6~3.8 Gy (RBE) per fraction. The treatment used a multi-leaf collimator(MLC) to adjust beam conformity, a ridge filter(RF) to spread-out the Bragg peak, and a bolus to adjust beam conformity at the distal end. A fixed horizontal nozzle was used at a couch angle of 0°, and the couch rotated 90° or 180° to achieve two-field intersecting or opposing fields. The photon IMRT plan used the Eclipse planning system (V13.5) from Varian company to design a fixed 5-field IMRT plan, with the same prescription dose as the CIRT plan. All plans were evaluated for dosimetric parameters based on organ-at-risk(OAR) dose limits, including target coverage, conformity index(CI), homogeneity index(HI), and OAR dose. There was no statistically significant difference in PTV V95 between the two plans (P=0.106), but Dmean, CI, and HI were statistically different, with the IMRT plan superior to the CIRT plan (P values of 0.048, 0.031, and 0.024, respectively). Regarding OAR dose, most OAR doses in the CIRT plan were smaller than those in the IMRT plan, but there was no statistically significant difference. However, the maximum dose to the optic chiasm, left and right lenses, and the mean dose to the brainstem and right optic nerve differed significantly between the two plans (P values of 0.034, 0.000, 0.047, 0.008, and 0.030, respectively). The distance between OAR and target volume was described using the minimum Hausdorff distance(HDmin), and when HDmin was greater than 7.1 mm, the CIRT plan was significantly superior to the IMRT plan. The uniform scanning CIRT was inferior to the photon IMRT plan in terms of target uniformity and conformity, but superior to the IMRT plan in terms of OAR dose. Whether the dosimetric advantages can be translated into clinical benefits remains to be further validated by clinical studies.
Comparative analysis of the dosimetric differences between Chinese-produced heavy ion accelerator uniform scanning and photon intensity-modulated radiotherapy(IMRT) treatment plans in the treatment of skull base malignancies. A retrospective analysis of the treatment plans for 8 patients with skull base malignancies treated with the domestic heavy ion equipment (Heavy Ion Medical Machine, HIMM) using uniform scanning, including 7 chordoma and 1 chondrosarcoma. Carbon ion radiotherapy(CIRT) plans were designed using the ciPlan planning system (V1.0) from Lanzhou Kejintaiji Company, with a prescription dose of 57.6~60.8 Gy (RBE) in the planning target volume, delivered in 16 fractions of 3.6~3.8 Gy (RBE) per fraction. The treatment used a multi-leaf collimator(MLC) to adjust beam conformity, a ridge filter(RF) to spread-out the Bragg peak, and a bolus to adjust beam conformity at the distal end. A fixed horizontal nozzle was used at a couch angle of 0°, and the couch rotated 90° or 180° to achieve two-field intersecting or opposing fields. The photon IMRT plan used the Eclipse planning system (V13.5) from Varian company to design a fixed 5-field IMRT plan, with the same prescription dose as the CIRT plan. All plans were evaluated for dosimetric parameters based on organ-at-risk(OAR) dose limits, including target coverage, conformity index(CI), homogeneity index(HI), and OAR dose. There was no statistically significant difference in PTV V95 between the two plans (P=0.106), but Dmean, CI, and HI were statistically different, with the IMRT plan superior to the CIRT plan (P values of 0.048, 0.031, and 0.024, respectively). Regarding OAR dose, most OAR doses in the CIRT plan were smaller than those in the IMRT plan, but there was no statistically significant difference. However, the maximum dose to the optic chiasm, left and right lenses, and the mean dose to the brainstem and right optic nerve differed significantly between the two plans (P values of 0.034, 0.000, 0.047, 0.008, and 0.030, respectively). The distance between OAR and target volume was described using the minimum Hausdorff distance(HDmin), and when HDmin was greater than 7.1 mm, the CIRT plan was significantly superior to the IMRT plan. The uniform scanning CIRT was inferior to the photon IMRT plan in terms of target uniformity and conformity, but superior to the IMRT plan in terms of OAR dose. Whether the dosimetric advantages can be translated into clinical benefits remains to be further validated by clinical studies.
2023, 40(2): 294-302.
doi: 10.11804/NuclPhysRev.40.2022103
Abstract:
In order to recycle and utilize industrial waste sugarcane molasses, a green membrane treatment technology: heavy ion track etching membrane was selected to filter the pretreated waste sugarcane molasses and then used to synthesize butyric acid by Clostridium tyrobutyricum(C. tyrobutyricum). The particle size distribution and polyphenol content of waste sugarcane molasses were determined by Laser Particle Size Analyzer and Ultra Performance Liquid Chromatography — Tandem Mass Spectrometry. Results showed that the toxic substances such as colloid, ash and polyphenols in molasses can be filtered by etching membrane. The staining results of Propidium Iodide indicated that the survival rate of C. tyrobutyricum in the waste sugarcane molasses treated with membrane was as high as 98.30%. The yield of butyric acid produced from waste sugarcane molasses after membrane treatment was 39.08 g/L, which was detected by Gas Chromatography — Mass Spectrometer. Waste sugarcane molasses was successfully transformed from waste to treasure by heavy ion track etching membrane combined with chemical method, with no pollution and zero emission during whole process. It improved the utilization efficiency of waste sugarcane molasses and the production performance of butyric acid by C. tyrobutyricum scientifically and effectively.
In order to recycle and utilize industrial waste sugarcane molasses, a green membrane treatment technology: heavy ion track etching membrane was selected to filter the pretreated waste sugarcane molasses and then used to synthesize butyric acid by Clostridium tyrobutyricum(C. tyrobutyricum). The particle size distribution and polyphenol content of waste sugarcane molasses were determined by Laser Particle Size Analyzer and Ultra Performance Liquid Chromatography — Tandem Mass Spectrometry. Results showed that the toxic substances such as colloid, ash and polyphenols in molasses can be filtered by etching membrane. The staining results of Propidium Iodide indicated that the survival rate of C. tyrobutyricum in the waste sugarcane molasses treated with membrane was as high as 98.30%. The yield of butyric acid produced from waste sugarcane molasses after membrane treatment was 39.08 g/L, which was detected by Gas Chromatography — Mass Spectrometer. Waste sugarcane molasses was successfully transformed from waste to treasure by heavy ion track etching membrane combined with chemical method, with no pollution and zero emission during whole process. It improved the utilization efficiency of waste sugarcane molasses and the production performance of butyric acid by C. tyrobutyricum scientifically and effectively.
Evaluation Methods of Neutron-induced Atomic Displacement Damage Cross Section Based on Nuclear Data
2023, 40(2): 303-313.
doi: 10.11804/NuclPhysRev.40.2022079
Abstract:
Neutron-induced irradiation damage is a major challenge for nuclear energy systems. Neutron irradiation damage is initiated by neutron-induced nuclear reactions and often quantified by the displacement damage, of which the conventional unit is the number of Displacements per Atom(DPA). Displacement damage is a consequence of atomic collision cascades in materials induced by recoil nuclei, which are referred to Primary Knock-on Atoms(PKAs) in radiation damage. Therefore, nuclear reaction data or nuclear reaction models are required to evaluate the neutron-induced displacement damage. Due to the lack of complete recoil spectra in the current evaluated nuclear data files, the calculation of displacement damage cross section (and thus the subsequent evaluation of irradiation damage level) should be based on the available differential cross sections and conservation laws. After the presentation of the two paths for evaluating neutron-induced displacement damage, the present work thoroughly summarizes the methods for computing displacement damage cross sections induced by different nuclear reaction types, including discrete and continuum binary reactions, neutron capture reaction, and the detailed discussion on many-body reactions. Then, the DPA cross sections of potential accident tolerant cladding material FeCrAl are calculated for various Cr and Al contents based on the recently evaluated ENDF/B-VIII.0 nuclear data library. Preliminary results show that the evaluation of neutron irradiation-induced DPA for FeCrAl is not sensitive to the content of Cr and Al, whereas the DPA in FeCrAl should be about 3%~4% higher than that in pure iron. The former conclusion implies that the evaluation of neutron irradiation-induced displacement damage can be performed with “arbitrary” contents of Cr and Al. However, it should be noted that the content of Cr and Al may influence the threshold displacement energies or the damage energy.
Neutron-induced irradiation damage is a major challenge for nuclear energy systems. Neutron irradiation damage is initiated by neutron-induced nuclear reactions and often quantified by the displacement damage, of which the conventional unit is the number of Displacements per Atom(DPA). Displacement damage is a consequence of atomic collision cascades in materials induced by recoil nuclei, which are referred to Primary Knock-on Atoms(PKAs) in radiation damage. Therefore, nuclear reaction data or nuclear reaction models are required to evaluate the neutron-induced displacement damage. Due to the lack of complete recoil spectra in the current evaluated nuclear data files, the calculation of displacement damage cross section (and thus the subsequent evaluation of irradiation damage level) should be based on the available differential cross sections and conservation laws. After the presentation of the two paths for evaluating neutron-induced displacement damage, the present work thoroughly summarizes the methods for computing displacement damage cross sections induced by different nuclear reaction types, including discrete and continuum binary reactions, neutron capture reaction, and the detailed discussion on many-body reactions. Then, the DPA cross sections of potential accident tolerant cladding material FeCrAl are calculated for various Cr and Al contents based on the recently evaluated ENDF/B-VIII.0 nuclear data library. Preliminary results show that the evaluation of neutron irradiation-induced DPA for FeCrAl is not sensitive to the content of Cr and Al, whereas the DPA in FeCrAl should be about 3%~4% higher than that in pure iron. The former conclusion implies that the evaluation of neutron irradiation-induced displacement damage can be performed with “arbitrary” contents of Cr and Al. However, it should be noted that the content of Cr and Al may influence the threshold displacement energies or the damage energy.
2023, 40(2): 314-326.
doi: 10.11804/NuclPhysRev.40.2022062
Abstract:
Redundant pump groups are widely used in various critical parts of nuclear power plants and play a vital role in ensuring nuclear safety. To enhance their reliability, this study models and analyzes the reliability of digital control of redundant pump groups under different redundancy modes. Firstly, a dynamic fault tree model of pump group failure is established based on the different operation and control logic of the digital control system for redundant pump groups under three redundancy modes. Secondly, the minimum cut-set method is employed, and a Markov model is constructed to obtain the solution approach for the dynamic fault tree under three modes. Finally, taking the digital control system for charging pumps in the RCV system of a nuclear power plant as a case study, the reliability of the system is quantitatively analyzed under the three redundancy modes. The research results indicate that, under normal operating conditions, the double hot standby redundancy mode exhibits the highest reliability for the digital control of charging pumps, followed by the cold-hot standby redundancy mode, while the double cold standby redundancy mode shows the lowest reliability. The present study provides valuable insights for improving the reliability of digital control for redundant pump groups.
Redundant pump groups are widely used in various critical parts of nuclear power plants and play a vital role in ensuring nuclear safety. To enhance their reliability, this study models and analyzes the reliability of digital control of redundant pump groups under different redundancy modes. Firstly, a dynamic fault tree model of pump group failure is established based on the different operation and control logic of the digital control system for redundant pump groups under three redundancy modes. Secondly, the minimum cut-set method is employed, and a Markov model is constructed to obtain the solution approach for the dynamic fault tree under three modes. Finally, taking the digital control system for charging pumps in the RCV system of a nuclear power plant as a case study, the reliability of the system is quantitatively analyzed under the three redundancy modes. The research results indicate that, under normal operating conditions, the double hot standby redundancy mode exhibits the highest reliability for the digital control of charging pumps, followed by the cold-hot standby redundancy mode, while the double cold standby redundancy mode shows the lowest reliability. The present study provides valuable insights for improving the reliability of digital control for redundant pump groups.
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