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Numerical and theoretical investigations of heat transfer characteristics in helium-xenon cooled microreactor core

Nuclear Science and Techniques 2023年第11期34卷 1-19页

作者： Tian‑Shi Wang Xiang Chai Chao‑Ran guan Xin‑yue Liu Jiao‑Long Deng hui He Xiao‑Jing Liu School of Nuclear Science and Engineering Shanghai JiaoTong UniversityShanghai 200240China

Helium-xenon cooled microreactors are a vital technological solution for portable nuclear reactor power *** exam-ine the convective heat transfer behavior of helium-xenon gas mixtures in a core environment,numerical simulations are conducted on a cylindrical coolant channel and its surrounding solid *** numerical methods are used to determine the effect and mechanisms of power and its distribution,inlet temperature and velocity,and outlet pressure on the distribution and change trend of the axial Nusselt ***,a theoretical framework that can describe the effect of power variation on the evolution of the thermal boundary layer is employed to formulate an axial distribution cor-relation for the Nusselt number of the coolant channel,under the assumption of a cosine distribution for the axial *** on the simulation results,the correlation coefficients are determined,and a semi-empirical relationship is identified under the corresponding operating *** correlation derived in this study is consistent with the simulations,with an average relative error of 5.3%under the operating ***,to improve the accuracy of the predictions near the entrance,a segmented correlation is developed by combining the Kays correlation with the aforementioned *** new correlation reduces the average relative error to 2.9%and maintains satisfactory accuracy throughout the entire axial range of the channel,thereby demonstrating its applicability to turbulent heat transfer calculations for helium-xenon gas mixtures within the core *** findings provide valuable insights into the convective heat transfer behavior of a helium-xenon gas mixture in a core environment.

关键词： Helium-xenon gas mixture Convective heat transfer Power distribution Numerical simulation Nusselt number correlation

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Chronic Intermittent Hypobaric Hypoxia Ameliorates Renal Vascular Hypertension Through Up-regulating NOS in Nucleus Tractus Solitarii

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Neuroscience Bulletin 2019年第1期35卷 79-90页

作者： Na Li yue guan Yan-Ming Tian hui-Jie Ma Xiangjian Zhang Yi Zhang Sheng Wang Department of Physiology Hebei Medical UniversityShijiazhuang 050017China Department of Physiology Basic Medical CollegeHebei UniversityBaoding 071000China Hebei Collaborative Innovation Center for Cardio-cerebrovascular Disease Shijiazhuang 050000China

Chronic intermittent hypobaric hypoxia(CIHH)is known to have an anti-hypertensive effect, which might be related to modulation of the baroreflex in rats with renal vascular hypertension(RVH). In this study, RVH was induced by the 2-kidney-1-clip method(2 K1 C) in adult male Sprague-Dawley rats. The rats were then treated with hypobaric hypoxia simulating 5000 m altitude for 6 h/day for 28 days. The arterial blood pressure(ABP), heart rate(HR), and renal sympathetic nerve activity(RSNA) were measured before and after microinjection of L-arginine into the nucleus tractus solitarii(NTS) in anesthetized *** excitatory postsynaptic currents(eEPSCs) and spontaneous EPSCs(sEPSCs) were recorded in anterogradely-labeled NTS neurons receiving baroreceptor afferents. We measured the protein expression of neuronal nitric oxide synthase(nNOS) and endothelial NOS(eNOS) in the NTS. The results showed that the ABP in RVH rats was significantly lower after CIHH treatment. The inhibition of ABP, HR, and RSNA induced by L-arginine was less in RVH rats than in sham rats, and greater in the CIHHtreated RVH rats than the untreated RVH rats. The eEPSC amplitude in NTS neurons receiving baroreceptor afferents was lower in the RVH rats than in the sham rats and recovered after CIHH. The protein expression of nNOS and e NOS in the NTS was lower in the RVH rats than in the sham rats and this decrease was reversed by CIHH. In short, CIHH treatment decreases ABP in RVH rats via upregulating NOS expression in the NTS.

关键词： Chronic intermittent hypobaric hypoxia Renal vascular hypertension Nitric oxide Renal sympathetic nerve activity Excitatory postsynaptic current

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2.5-Dimensional modeling of EM logging-while-drilling tool in anisotropic medium on a Lebedev grid

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Petroleum Science 2023年第1期20卷 249-260页

作者： Zhen-guan Wu Hu Li Xi-Zhou yue School of Geoscience and Technology Southwest Petroleum UniversityChengduSichuan610500China Maxwell Dynamics Inc. HoustonTX77074USA Well-tech R&D Institute China Oilfield Services LimitedBeijing101149China

A 2.5D finite-difference(FD)algorithm for the modeling of the electromagnetic(EM)logging-whiledrilling(LWD)tool in anisotropic media is *** FD algorithm is based on the Lebedev grid,which allows for the discretization of the frequency-domain Maxwell's equations in the anisotropic media in 2.5D scenarios without *** leads to a system of linear equations that is solved using the multifrontal direct solver which enables the simulation of multi-sources at nearly the cost of simulating a single source for each *** addition,near-optimal quadrature derived from an optimized integration path in the complex plane is employed to implement the fast inverse Fourier Transform(IFT).The algorithm is then validated by both analytic and 3D *** results show that two Lebedev subgrid sets are sufficient for TI medium,which is common in geosteering *** number of quadrature points is greatly reduced by using the near-optimal quadrature method.

关键词： 2.5D modeling Electromagnetic logging-while-drilling Anisotropic medium Lebedev grid

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Syntheses,Crystal Structures and DNA-Binding Properties of Zn(Ⅱ)and Mn(Ⅱ)Complexes Based on Imidazole Derivatives and Carboxylic Acid

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Chinese Journal of Structural Chemistry 2022年第3期41卷 260-269,I0014页

作者： guan hui-Chao SONG Xiao-Tong LIU Gui-Bao yue Shu-Mei College of Chemistry Changchun Normal UniversityChangchun 130032China

Complexes[Zn(pbm)(5-hip)_(3)](1),[Zn(pbm)(5-nip)3](2),[Mn(pbm)(H_(3)btc)_(2)(H_(2)O)](3)and[Mn(pbm)(5-nip)_(3)](4),where H2HIPA=5-hydroxyisophthalic acid,H2nip=5-nitroisophthalic acid,H3btc=tri-mesic acid and pbm(pyridine benzene chelate material)=2-(2-pyridyl)benzimidazole,were identified via sin-gle-crystal XRD analyses.1,2 and 4 pertain to the monoclinic space group C2/c,while 3 belongs to the triclinic space group *** interplay of CT-DNA with those complexes was delineated using ultraviolet,fluorescence,and circular dichroism(CD)spectroscopy and viscosity *** 1,2,3 and 4 interact with CT-DNA in an electrostatic or grooving *** wish to offer a theory-wise foundation for developing anti-tumor medi-cines.

关键词： single-crystal structures spectroscopy CT-DNA binding 2-(2-pyridyl)benzimidazole

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Adhesion Performances Between Two Orthotropic Solids Influenced by Temperature Increment

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Acta Mechanica Solida Sinica 2024年第3期37卷 430-443页

作者： Qing-hui Luo yue-Ting Zhou School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai200092China

The classical adhesive contact models belong to isothermal adhesion theories,where the effect of temperature on adhesion was ***,a number of experimental results indicated that the adhesion behaviors can be significantly affected by *** this paper,the two-dimensional non-slipping anisothermal adhesion behaviors between two orthotropic elastic cylinders are investigated within the framework of the Johnson-Kendall-Roberts *** stated problem is reduced to the coupled singular integral equations by virtue of the Fourier integral transform,which are solved analytically with the analytical function *** closed-form solutions for the stress fields in the presence of thermoelastic effect are *** stable equilibrium state of contact system is determined by virtue of the Griffith energy *** effect of temperature difference on adhesion behaviors between orthotropic solids is *** is found that the difference between the oscillatory and non-oscillatory solutions increases with increasing the degree of anisotropy of orthotropic *** oscillatory solution cannot be well approximated by the non-oscillatory solution for the orthotropic materials with relatively high anisotropy.

关键词： Adhesive contact Non-slipping JKR model Temperature Griffith energy balance

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Expression of cell cycle regulator p57^(kip2), cyclinE protein and proliferating cell nuclear antigen in human pancreatic cancer: An immunohistochemical study

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World Journal of Gastroenterology 2005年第32期11卷 5057-5060页

作者： hui yue hui-Yong Jiang Institute for Digestive Medicine Nanfang Hospital Southern Medical University Guangzhou 510515 Guangdong Province China Department of Pathology Nanfang Hospital Southern Medical University Guangzhou 510515 Guangdong Province China

AIM： To investigate the effects of p57^kip2, cyclinE protein and proliferating cell nuclear antigen （PCNA） on occurrence and progression of human pancreatic cancer. METHODS： The expression of p57^kip2, cyclinE protein and PCNA in tumor tissues and adjacent tissues from 32 patients with pancreatic cancer was detected by SP immunohistochemical technique. RESULTS： The positive expression rate of p57^kip2 protein in tumor tissues was 46.9%, which was lower than that in adjacent pancreatic tissues （χ^2 = 5.317, P〈0.05）. p57^kip2 protein positive expression remarkably correlated with tumor cell differentiation （P〈0.05）, but not with lymph node metastasis （P〉0.05）. The positive expression rate of cyclinE protein in tumor tissues was 68.8%, which was higher than that in adjacent pancreatic tissues （χ^2 = 4.063, P〈0.05）. CyclinE protein positive expression significantly correlated with tumor cell differentiation and lymph node metastasis （P〈0.05）. The positive expression rate of PCNA in the tumor tissues was 71.9%, which was higher than that in adjacent pancreatic tissues （χ^2 = 5.189, P〈0.05）. PCNA positive expression remarkably correlated with tumor cell differentiation and lymph node metastasis （P〈0.05）. CONCLUSION： The decreased expression of p57^kip2 and/or overexpression of cyclinE protein and PCNA may contribute to the occurrence and progression of pancreatic cancer. p57^kip2, cyclinE protein, and PCNA play an important role in occurrence and progression of pancreatic cancer.

关键词： p57^kip2 CyclinE PCNA Human pancreatic cancer

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Automatic Requirement Dependency Extraction Based on Integrated Active Learning Strategies

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Machine Intelligence Research 2024年第5期21卷 993-1010页

作者： hui guan Guorong Cai Hang Xu Department of Computer Science and Technology Shenyang University of Chemical TechnologyShenyang110142China Key Laboratory of Industrial Intelligence Technology on Chemical Process Shenyang110142China

Since requirement dependency extraction is a cognitively challenging and error-prone task,this paper proposes an automatic requirement dependency extraction method based on integrated active learning *** this paper,the coefficient of variation method was used to determine the corresponding weight of the impact factors from three different angles:uncertainty probability,text similarity difference degree and active learning variant prediction divergence *** combining the three factors with the proposed calculation formula to measure the information value of dependency pairs,the top K dependency pairs with the highest comprehensive evaluation value are selected as the optimal *** the optimal samples are continuously added into the initial training set,the performance of the active learning model using different dependency features for requirement dependency extraction is rapidly ***,compared with other active learning strategies,a higher evaluation measure of requirement dependency extraction can be achieved by using the same number of ***,the proposed method using the PV-DM dependency feature improves the weight-F1 by 2.71%,the weight-recall by 2.45%,and the weight-precision by 2.64%in comparison with other strategies,saving approximately 46%of the labelled data compared with the machine learning approach.

关键词： Requirement dependency dependency extraction dependency features integrated active learning strategies coefficient of variation

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Review on synergistic damage effect of irradiation and corrosion on reactor structural alloys

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Nuclear Science and Techniques 2024年第3期35卷 109-141页

作者： hui Liu guan-Hong Lei He-Fei Huang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research *** paper provides a comprehensive review of the synergistic effects on the third-and fourth-generation fission nuclear energy structural materials used in pressurized water reactors and molten salt *** competitive mechanisms of multiple influencing factors,such as the irradiation dose,corrosion type,and environmental temperature,are summarized in this *** approaches are proposed to alleviate the synergistic damage caused by irradiation and corrosion,thereby promoting in-depth research in the future and solving this key challenge for the structural materials used in reactors.

关键词： Irradiation and corrosion Synergistic effect Austenitic stainless steels Nickel-based alloys Reactors

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Multi-area detection sensitivity calculation model and detection blind areas influence analysis of photoelectric detection target

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Defence Technology（防务技术） 2022年第4期18卷 547-556页

作者： Han-shan Li Xiao-qian Zhang hui guan School of Electronic and Information Engineering Xi’an Technological UniversityXi’an710021China

Multi-element array photoelectric detector is the core devices to form a photoelectric detection target with a large field of *** photoelectric detection target brings about the problem of uneven detection sensitivity distribution in the detection *** improve the uneven detection sensitivity of this photoelectric detection target,this paper analyzes the distribution law of the uneven detection sensitivity of the photoelectric detection target using the multi-element array photoelectric detector,dissects the main factors affecting the detection sensitivity according to the photoelectric detection principle,establishes the calculation model of detection sensitivity of the photoelectric detection target in the different detection areas and proposes a method to improve the detection sensitivity by compensating the gain of each unit photoelectric *** analysis of simulation and experimental results show that the proposed method of photoelectric detection target can effectively improve the output signal amplitude of the projectile under the certain detection distance,in particular,the output signal amplitude of the projectile is significantly increased when the projectile passes through the detection blind *** experimental results are consistent with the simulation results,which verify the effectiveness of the proposed improvement method.

关键词： Projectile Photoelectric detection target Multi-element array photoelectric detector Detection sensitivity Detection screen

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Heteroscedastic regression analysis method for mixed data

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航空动力学报 2011年第4期26卷 721-726页

作者： FU hui-min yue Xiao-rui Research Center of Small Sample Technology Beijing University of Aeronautics and Astronautics Beijing 100191 China

The heteroscedastic regression model was established and the heteroscedastic regression analysis method was presented for mixed data composed of complete data,type-Ⅰ censored data and type-Ⅱ censored data from the location-scale *** best unbiased estimations of regression coefficients,as well as the confidence limits of the location parameter and scale parameter were ***,the point estimations and confidence limits of percentiles were ***,the traditional multiple regression analysis method which is only suitable to the complete data from normal distribution can be extended to the cases of heteroscedastic mixed data and the location-scale *** the presented method has a broad range of promising applications.

关键词： heteroscedastic regression analysis censored data performance test life prediction reliability analysis

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