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  • 2025

    Abstract

    In response to the nuclear material accounting and control system, uranium or plutonium mass and also the isotope abundance should be quantified comprehensively. Commonly, in nuclear safeguards and nuclear security field, active mode is most reasonable for nuclides with low spontaneous rates like uranium measuring for neutron accounting equipment. The spatial detection efficiency and the number of induced fission neutrons are researched in the paper by Monte Carlo simulation and laboratory experiments. A geometric model is built for Monte Carlo simulation to symbolize the measurement of neutrons. The data are assayed with the fission time randomly generated by matlab that conforms to the Poisson distribution to obtain the neutron pulse sequence. The multiplicity shift register (MSR) simulation program performs statistical analysis on the neutron pulse sequence to obtain the corresponding count rates. After that, U3O8 standard source was placed at more than 50 positions, and the comprehensive simulations were conducted. Spatial detection efficiency is practically consistent in the measurement cavity, which proves that the main influencing factors of the neutron measurement results are the spatial distribution of the induction source and the sample. The spatial distribution curves obtained in the fitting results can be used to correct the spatial effect of neutron measurement in the active mode of this device and provide a reference for the subsequent optimization of active neutron measurement equipment and the application of different measurement scenarios.


    • Book : 11(2)
    • Pub. Date : 2025
    • Page : pp.024501
    • Keyword :
  • 2025

    Abstract

    Niobium as refractory element holds ability to arrest the primary radiation damage in reactor's fissionable conditions and can withstand high-temperature applications. We have inclined the investigation of irradiated Nb Σ 5 symmetric-tilt angled grain boundary (STGB) models at two high-angled grain boundary misorientation: 53.13 deg (Σ 5(2-10)/(120)) and 36.87 deg (Σ 5(3-10)/(130)), respectively. A hybrid of Ziegler-Biersack-Littmark (ZBL) and embedded atom method (EAM) potentials were superimposed to simulate radiation damage. Statistical averaging of the displacement cascades was conducted to study the dynamic evolution of the point defects and interstitial clusters at varying magnitudes of primary knock-on atom (PKA) energies, irradiation temperatures, and PKA directions. The irradiated grain bounary (GB) models were compared with an irradiated bulk Nb specimen, and the results of the study indicate that the irradiated Nb system with greater misorientation angle, i.e., Nb Σ 5 (ɵ = 53.13 deg) survived with lower number Frenkel pair defects as well as the population small-sized interstitial clusters. The point defect cluster analysis indicated the highest population of interstitial clusters survived in Nb STGB models were irradiated along <1 3 5> PKA direction and 100 keV recoil energies respectively.


    • Book : 147(3)
    • Pub. Date : 2025
    • Page : pp.031002
    • Keyword :
  • 2025

    Abstract

    The need for the replacement of cadmium, indium, and tellurium in their compounds for sensor applications is a novel study. The copper zinc tin sulfide (Cu2ZnSnS4) thin films were synthesized from Cu (99.99%), Sn (99.99%), and Zn (99.99%) using the thermal evaporation method. The same volumetric parameters were maintained throughout the synthesis process. The films were further irradiated using an isotope of cesium-137 (Cs-137) from a gamma source at different doses (0-0.6 kGy) and dose rates of 0.1007 Gy/h at room temperature. Both the pristine (0 kGy) and irradiated (0.1, 0.3, and 0.6 kGy) films were characterized with a Raman spectroscope, a field emission scanning electron microscope (FESEM) with the JEOL JSM-7600F model, energy dispersive X-rays (EDX), an ultraviolet-visible-near infrared (UV-Vis-NIR) spectroscope, and four-point probe techniques. The Raman results confirmed that all the films for both pristine and irradiated films have a main and secondary phases. The EDX results showed that the pristine and 0.1 kGy films were Cu-rich films, while the 0.3 kGy and 0.6 kGy films turned out to be Zn-rich films with an increase in gamma radiation dose. The optical properties of all the films showed also that the band gap decreased from 1.6 to 1.48±0.03 eV for the pristine and irradiated films, while the electrical resistivity results decreased as the gamma radiation dose increased. However, as the structural, optical, and electrical properties of the Cu2ZnSnS4 thin films responded linearly with the increasing gamma radiation dose, this suggests the usefulness and possibility of designing a new solid-state sensor for dosimetry applications to replace cadmium telluride (CdTe) and copper indium gallium sulfide (CIGS) thin films.


    • Book : 11(2)
    • Pub. Date : 2025
    • Page : pp.022002
    • Keyword :
  • 2025

    Abstract

    In indirect-drive inertial confinement fusion (ICF) research, the meticulous design and optimization of laser parameters are crucial for achieving high-gain ignition. The intensity of the toe laser, used for ablating the hohlraum sealing membrane, is a subtle but equally critical parameter. This study introduces a novel experimental approach using the Velocity Interferometer System for Any Reflector (VISAR) to assess the impact of toe laser intensity on the compression of fusion capsules. By tracking the reflectivity of tracer layers and shock velocities in liquid deuterium, the adverse effects of insufficient toe laser intensity on capsule compression have been unveiled for the first time. From a comparison with hydrodynamic simulations, we show that below a critical threshold of 0.23 × 1014 W cm−2, the adiabat, a measure of the fuel’s compression efficiency, increases markedly with the toe laser intensity decreases, whereas it remains stable within the range of (0.23 ∼ 7) × 1014 W cm−2. Our findings provide critical insights on toe laser parameter design, enhancing our understanding of the role of toe laser intensity in ICF experiments. This research not only refines the parameters for laser operation but also underscores the importance of precision in achieving the desired implosion efficiency, contributing to the development of nuclear fusion as a clean energy source.


    • Book : 65(1)
    • Pub. Date : 2025
    • Page : pp.016032
    • Keyword :
  • 2025


    • Book : 1010()
    • Pub. Date : 2025
    • Page : pp.116751
    • Keyword :
  • 2025


    • Book : 1010()
    • Pub. Date : 2025
    • Page : pp.116753
    • Keyword :
  • 2025


    • Book : 217()
    • Pub. Date : 2025
    • Page : pp.111604
    • Keyword :
  • 2025

    Abstract

    Experiments are carried out in CIMPLE-PSI, to understand the recrystallization behavior of tungsten (W) exposed under very-high target temperature and ITER relevant long He+-fluence. The effect of helium bubbles on possible retardation of the recrystallization process is also studied. W samples were simultaneously exposed under He plasma and annealed by the plasma heat-load, in contrast to previously reported experiments in literature, which were carried out sequentially. Exposed samples are characterized by field emission scanning electron microscopy (FESEM), Vickers surface micro-hardness, nano-hardness and electron backscattered diffraction (EBSD). It is observed that the sample exposed to plasma under the highest temperature (1866 K) suffered acute retarded grain growth. This also contained small, unrecovered grains on the exposed surface. FESEM imaging of the cross-sections confirms that relatively smaller helium bubbles still form even at very high temperature conditions, which can impede the grain growth locally, whenever they are forming right on the grain boundaries. This results in an inhomogeneous mixture of surface grains with sizes ranging from a few micrometers to a few tens of micrometers. EBSD estimates that the plasma exposed surface was only 34% recrystallized. The second sample exposed at a lower temperature (1699 K) but for three times higher fluence (ion fluence: 1.19 × 1027 m−2) was almost fully recrystallized, which shows retardation diminishes very fast with the duration of the exposure. Hardness measurements were undertaken to understand the variation with plasma exposure/annealing temperature and the extent of recrystallization, with three different probing length scales, spanning from a few hundred nanometers to several micrometers. Both helium plasma exposed W samples are observed to undergo retarded softening up to a depth of a few hundred nanometers from the surface, compared to when the metal may be recrystallized by simple heating, without any plasma exposure.


    • Book : 65(1)
    • Pub. Date : 2025
    • Page : pp.016017
    • Keyword :
  • 2025

    Abstract

    Plasmablastic lymphoma (PBL) is an uncommon and aggressive large B‐cell lymphoma that affects immunocompromised individuals. The orofacial region is the most commonly affected site. The primary aim of the article was to review systematically, the cases of oral PBL and consolidate their clinic‐pathological, and molecular characteristics, rehabilitation, and outcome in Human immunodeficiency virus (HIV)‐infected individuals. An electronic literature search was done and 28 articles with a total of 32 cases, of which 27 patients were adults and 5 were pediatrics were included in the review based on the inclusion criteria. Oral PBL was found to be common in HIV‐affected males, frequently involving the gingiva. Histopathology revealed monomorphic neoplastic atypical cells with plasmablastic features and cohesive growth patterns. Immunohistochemistry revealed strong positivity for CD138, and CD 79a. The prognosis of oral PBL in patients with HIV was poor in both adult and pediatric age groups, however, pediatric age groups showed a worse prognosis. Hence, it is crucial to correctly diagnose oral PBL, surgically treat the patients along with chemotherapy and/or radiation therapy, and start ART in HIV‐positive individuals.


    • Book : 22(1)
    • Pub. Date : 2025
    • Page : pp.e1265
    • Keyword :
  • 2025

    This research paper monitors the patient’s health using sensor data, cloud, and big data Hadoop tools and used to predict heart attack and related results were discussed in detail. The integration of big data, and wearable sensors in pervasive computing has significantly enhanced healthcare services. This proposal focuses on developing an advanced healthcare monitoring system tailored for tracking the activities of elderly individuals. The wearable sensors are placed on humans at a right angle, left arm, right arm, and chest to collect the data. The large data are split into smaller segments using the map and reduce process of big data Hadoop tools. The intensity-modulated radiation therapy (IMRT) approach is used for the mapping phase and deep convolutional neural network (DCNN), deep belief network (DBN), and long short-term memory (LSTM) and proposed deep learning heart rate prediction (DLHRP) algorithms are used for the combiner/reduce phase. The reduction process combines similar segments of data to predict identical classes to predict the severity of human conditions. The proposed IMRT-DLHRP system has improved performance of 96.34% accuracy compared with 84.25%, 89.47%, and 91.58% compared to DCNN, DBN, and LSTM respectively, therefore proposed framework has significant improvement over existing approaches.


    • Book : 37(1)
    • Pub. Date : 2025
    • Page : pp.300
    • Keyword :