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Investigation into the flow and heat transfer characteristics in liquid metal cooled narrow rectangular channel with rough surfaces

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Case Studies in Thermal engineering 2025年 72卷

作者： Xue Zhang Wenpei Feng Xiaolong Yang Hongxing Yu Jian Deng Sijia Du Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China Chengdu 610213 China College of Nuclear Technology and Automation Engineering Chengdu University of Technology Chengdu 610059 China

This study investigates the impact of roughness elements on fluid flow and heat transfer characteristics in narrow rectangular channels. The results show that when the fluid flows over roughness elements, it induces vortices near the wall, disturbing the flow and heat transfer boundary layers. This enhances heat transfer while simultaneously increasing flow resistance. Among different roughness types, cylindrical roughness elements demonstrate a more substantial improvement in both heat transfer efficiency and friction factor compared to cubic elements. The Nusselt number is found to be non-monotonic related to the height of the roughness elements, while the friction factor increases with height. Additionally, larger roughness element diameters lead to higher Nusselt numbers and friction factors. Further analysis reveals that under conditions where the spacing and height remain unchanged, an increase in the roughness elements quantity results in a diminished enhancement of heat transfer. The base edge length of the roughness elements has a more significant impact on heat transfer capacity than the additional heated area, while the additional area primarily affects the flow resistance, causing the friction factor to increase with the number of roughness elements.

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Frequency-modulated continuous-wave quantum interferometric lidar with enhanced accuracy and resolution

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Physical Review applied 2025年第3期23卷 034055-034055页

作者： Ming-Da Huang Zhan-Feng Jiang Hong-Yi Chen Ying Zuo Xiao-Peng Hu Hai-Dong Yuan Li-Jian Zhang Qi Qin College of Physics and Optical Engineering Shenzhen University Shenzhen 518060 China State Key Laboratory of Radio Frequency Heterogeneous Integration Shenzhen University Shenzhen 518060 China Institute of Intelligent Optical Measurement and Detection Shenzhen University Shenzhen 518060 China Shenzhen Institute for Quantum Science and Engineering Southern University of Science and Technology Shenzhen 518055 China International Quantum Academy Shenzhen 518048 China Guangdong Provincial Key Laboratory of Quantum Science and Engineering Southern University of Science and Technology Shenzhen 518055 China National Laboratory of Solid State Microstructures and College of Engineering and Applied Sciences Nanjing University Nanjing 210093 China Department of Mechanical and Automation Engineering The Chinese University of Hong Kong Shatin Hong Kong SAR China Quantum Science Center of Guangdong-HongKong-Macao Greater Bay Area (Guangdong) Shenzhen 518045 China

The range and velocity of a moving object can be ascertained using the sensing technique known as light detection and ranging (lidar). It has recently been suggested that quantum lidar, which uses entangled states of light, can enhance the capabilities of lidar. Entangled pulsed light is used in prior quantum lidar approaches to assess both range and velocity at the same time using the time of flight and Doppler shift. However, the detection of entangled pulsed light is often inefficient and constrained by the temporal resolution of the detectors. Here, we investigate a quantum lidar utilizing a linear interferometer operating on a frequency-modulated continuous wave (FMCW) instead of pulses. Our findings demonstrate that the quantum FMCW lidar enables simultaneous measurements of range and velocity with quantum-enhanced accuracy and resolution, as well as superresolution phase imaging. Through self-heterodyne detection with a linear optical design, the signals of the quantum FMCW lidar with entangled photon pair can be efficiently carried out electronically by down-converting the optical signal to the microwave region. As a result, it is better suited for practical implementations.

关键词： Frequency modulation

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Energy storage mechanism of high-loading MnO2 for aqueous ammonium-ion supercapacitor

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Journal of Energy Storage 2025年 117卷

作者： Huang, Zeyu Chen, Yuchen Luo, Jiaqi Gao, Jie Zhang, Yaxiong Tian, Guiying Yang, Guo Key Laboratory of Nuclear Physics and Ion-Beam Application Institute of Modern Physics Fudan University Shanghai200433 China School of Physical Science and Technology Lanzhou University Lanzhou730000 China Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai201800 China College of Chemical Engineering and Material Science Tianjin University of Science and Technology 13th Avenue 29 TEDA Tianjin300457 China

Supercapacitors, distinguished by the high power density, hold considerable promise for use in portable energy storage devices. However, their relatively low energy density remains a major barrier limiting their comprehensive application. Two potential strategies to overcome this limitation involve increasing the mass loading of electrode materials and adopting appropriate electrolytes. Herein, a novel aqueous ammonium-ion supercapacitor (AASC), featuring electrodes with an ultrahigh loading of MnO2 (> 50 mg cm−2) and utilizing an (NH4)2SO4 solution as the electrolyte, has been developed. The results indicate that an MnO2 electrode loaded up to 68 mg cm−2 exhibits an excellent capacitance of 18 F cm−2 in 1 M (NH4)2SO4 electrolyte at 1 mA cm−2, surpassing the areal capacitance of most reported MnO2 electrodes. Moreover, electrochemical impedance spectroscopy results suggest the formation of a solid electrolyte interface, which is an important factor in potentially enhancing the performance of supercapacitors. Density functional theory calculations reveal that Ε-MnO2 offers higher ammonium adsorption and improved conductivity compared to δ-MnO2, favouring the storage and migration of NH4+. These significant findings represent a major step forward in the development of supercapacitor technology. © 2025

关键词： Electrochemical electrodes

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Physical design of positronium time of f light spectroscopy apparatus

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Chinese Physics C 2010年第12期34卷 1890-1894页

作者：姜小盼张子良秦秀波于润升王宝义 Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics CAS Graduate University of Chinese Academy of Sciences College of Applied Nuclear Technology & Automation Engineering Chengdu University of Technology

Positronium time of flight spectroscopy（Ps-TOF）is an effective technique for porous material *** has advantages over other techniques for analyzing the porosity and pore tortuosity of *** paper describes a design for Ps-TOF apparatus based on the Beijing intense slow positron beam,supplying a new material characterization *** order to improve the time resolution and increase the count rate of the apparatus,the detector system is *** 3 eV o-Ps,the time broadening is 7.66 ns and the count rate is 3 cps after correction.

关键词： positronium time of flight spectroscopy （Ps-TOF） positron annihilation plastic scintillator timebroadening count rate

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Temperature Field Simulation and Experimental Study of Anti‑backlash Single‑Roller Enveloping Hourglass Worm Gear

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Chinese Journal of Mechanical engineering 2020年第4期33卷 77-86页

作者： Shisong Wang Shike Wang Jie Wang Xingqiao Deng School of Mechanical Engineering Xihua UniversityChengdu 611730China College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China

In gear transmission,temperature rise has a non-negligible impact on the accuracy,noise and transmission ***,there is no relevant research on the temperature rise of the anti-backlash single-roller enveloping hourglass worm(ASEHW)*** solve this problem,based on tribology principle and Hertz contact theory,the thermal power calculation method of the ASEHW gear was proposed for the first time and thermal analysis was carried out by Ansys *** bulk temperature of the ASEHW gear under four different rotating speed(300 r/min,600 r/min,900 r/min,1200 r/min)is *** main factors causing temperature rise of the ASEHW gear are analyzed ***,an experimental study is performed to verify the simulation results and validate the theory *** theory presented in this paper provides a solution for the thermal power calculation of ASEHW *** research provides a theoretical basis for further optimization of ASEHW gear.

关键词： Roller enveloping hourglass worm gear Finite element analysis Temperature field

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The neutron energy spectrum obtained using energy spectrum superposition method for boron neutron capture therapy

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IEEE Transactions on nuclear Science 2025年

作者： Yang, Junkai Deng, Haopeng Wang, Pingquan Zhang, Hui Hu, Zhimeng Guo, Likai Peng, Min Zeng, Junmei Chu, Chungming Paul Xiao, Lin Guo, Hongyu Gorini, Giuseppe Nanjing University College of Engineering and Applied Sciences Nanjing 210093 China National Institute of Metrology Beijing 100029 China Nanjing University of Aeronautics and Astronautics Department of Nuclear Science and Technology Nanjing 210093 China Department of Physics University of Milan Bicocca Milan 20126 Italy

The neutron energy spectrum and fluence rate constitute critical determinants of tumor absorbed dose and therapeutic efficacy in the Neutron Capture Therapy (NCT). Variations in tumor depth and morphology, combined with accelerator beam intensity fluctuations, make it challenging to quickly obtain an accurate neutron energy spectrum. This study develops an Energy Spectrum Superposition Method (ESSM) that enables rapid neutron spectrum reconstruction through parameter retrieval from precomputed neutron transport databases. The methodology is validated using a Beam Shape Assembly (BSA) with three-layer moderator of AlF₃-32.5cm, CaF₂-22.5cm and TiF₃-2cm. Compared to the traditional simulation-based method, the energy spectrum obtained by ESSM demonstrates improved smoothness and superior statistical quality. For the two physical processes—proton bombardment on the target and neutron injection into the BSA—the neutron fluence rate ratios relative to the ESSM and the traditional simulation-based method were 0.958 and 0.996, respectively. After integrating the two physical processes, the BSA's emission window demonstrated a fluence rate ratio of 0.977. Furthermore, when the number of calculated particles is 3×10⁸, the equivalent computation efficiency is a 16,500-fold enhancement, which can significantly reduce the time needed to calculate. The achieved rapid calculation demonstrates clinical viability for real-time TPS (treatment planning system) operation during image-guided BNCT procedures. © 1963-2012 IEEE.

关键词： BNCT BSA Database ESSM Neutron energy spectrum

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Estimation method for parameters of overlapping nuclear pulse signal

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nuclear Science and Techniques 2017年第1期28卷 80-87页

作者： Hong-Quan Huang Xiao-Feng Yang Wei-Cheng Ding Fang Fang College of Nuclear Technology and Automation Engineering Chengdu University of Technology Fundamental Science on Radioactive Geology and Exploration Technology Laboratory East China Institute of Technology

Identification of nuclear pulse signal is of importance in radioactive measurements,especially in recognizing adjacent overlapping nuclear *** this article,we propose an estimation method for parameters of typical overlapping nuclear pulse ***,the nuclear pulses are regarded as individual genes and the norm is set as the fitness ***,the global optimal solution is found by searching the population of genetic algorithm,so as to estimate the parameters of nuclear *** high precision,this method can identify parameters of overlapping nuclear pulses in the Sallen-Key Gaussian signal decomposition *** pulse recognition method is of great significance to improve the precision of radioactive measurement and is suitable for serious overlap of nuclear pluses.

关键词： nuclear pulse Overlapping Parameter identification

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Retraction Notice: A Novel Radio Frequency Identification Collision Resolution Method Based on Statistical Learning

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IEEE Access 2025年 13卷 31658-31658页

作者： Zhong Dongbo School of Automation Nanjing University of Science and Technology Nanjing China School of Information Engineering Jiangxi College of Applied Technology Ganzhou China

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Method for rapid warning and activity concentration estimates in online waterγ-spectrometry systems

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nuclear Science and Techniques 2024年第3期35卷 1-12页

作者： Meng Wang Yi Gu Mao-Lin Xiong Liang-Quan Ge Qing-Xian Zhang Guo-Qiang Zeng Heng Lu Sheng-Liang Guo College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province (Chengdu University of Technology)Chengdu 610059China Chengdu New Ray Technology Co.Ltd Chengdu 610052China

Onlineγ-spectrometry systems for inland waters,most of which extract samples in situ and in real time,are able to produce reliable activity concentration measurements for waterborne radionuclides only when they are distributed relatively uniformly and enter into a steady-state diffusion regime in the measurement *** protect residents’health and ensure the safety of the living environment,better timeliness is required for this measurement *** address this issue,this study established a mathematical model of the online waterγ-spectrometry system so that rapid warning and activity estimates can be obtained for water under non-steady-state(NSS)*** addition,the detection efficiency of the detector for radionuclides during the NSS diffusion process was determined by applying the computational fluid dynamics technique in conjunction with Monte Carlo *** this basis,a method was developed that allowed the online waterγ-spectrometry system to provide rapid warning and activity concentration estimates for radionuclides in *** analysis of the NSS-mode measurements of^(40)K radioactive solutions with different activity concentrations determined the optimum warning threshold and measurement time for producing accurate activity concentration estimates for *** experimental results show that the proposed NSS measurement method is able to give warning and yield accurate activity concentration estimates for radionuclides 55.42 and 69.42 min after the entry of a 10 Bq/L^(40)K radioactive solution into the measurement chamber,*** times are much shorter than the 90 min required by the conventional measurement ***,the NSS measurement method allows the measurement system to give rapid(within approximately 15 min)warning when the activity concentrations of some radionuclides reach their respective limits stipulated in the Guidelines for Drinking-water Quality of the WHO,suggesting that this method con

关键词： Water radioactivity monitoring Dynamic detection efficiency Rapid warning Activity estimation

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Renewable energy education in Middle Eastern and North African universities

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Social Sciences and Humanities Open 2025年 11卷

作者： Alemam, Asem Khasawneh, Mohammad A.S. Altawil, Muthana Afgan, Imran Mechanical & Nuclear Engineering Department Khalifa University of Science and Technology Abu Dhabi United Arab Emirates Department of Mechanical Engineering Jordan University of Science and Technology Irbid 22110 Jordan Mechanical Engineering Department Al-Huson University College Al-Balqa Applied University Al-Huson Irbid Jordan Department of Mechanical Engineering Faculty of Engineering University of Debrecen H4028 Debrecen Ótemető U. 2-4. Hungary

This study examines renewable energy education at 29 universities across 9 MENA countries via questionnaires sent to engineering faculties. Results indicate that such courses are mainly concentrated in mechanical, electrical, and energy engineering departments, predominantly taught by Ph.D. holders, with a focus on solar and wind energy. Motivations for teaching include knowledge acquisition, opportunity exploration, and employment prospects. Predominantly master's and bachelor's level courses are offered, with few doctoral programs. Assessment is primarily through written exams, supported by textbooks and research articles. Recommendations include enhancing laboratories, fostering academic collaboration, expanding courses, and increasing practical projects. The MENA educational model aligns more with North American than European standards. © 2025 The Authors

关键词： engineering education Graduate programs Renewable energy Undergraduate programs

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