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Study on the effect of thermal deformation on the liquid seal of high-temperature molten salt pump in molten salt reactor

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Nuclear Science and Techniques 2023年第2期34卷 128-138页

作者： xing‑Chao shen Yuan Fu Jian‑Yu Zhang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

The high-temperature molten salt pump is the core equipment in a molten salt reactor that drives the flow of the molten salt *** stability is key to the continuous and reliable operation of the molten salt pump,and the liquid seal at the wear ring can affect the dynamic characteristics of the rotor *** the molten salt pump is operated in the hightemperature molten salt medium,thermal deformation of the submerged parts inevitably occurs,changing clearance between the stator and rotor,affecting the leakage and dynamic characteristics of the *** this study,the seal leakage,seal dynamic characteristics,and rotor system dynamic characteristics are simulated and analyzed using finite element simulation software based on two cases of considering the effect of seal thermal deformation effect or *** results show a significant difference in the leakage characteristics and dynamic characteristics of the seal obtained by considering the effect of seal thermal deformation and neglecting the effect of thermal *** leakage flow rate decreases,and the first-order critical speed of the seal-bearing-rotor system decrease after considering the seal’s thermal deformation.

关键词： High-temperature molten salt pump Seal thermal deformation Leakage characteristics Seal dynamic characteristics Critical speed

Effect of Grain Size on the Precipitation Behaviour in Super-Ferritic Stainless Steels During a Long-Term Ageing

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Acta Metallurgica Sinica(English Letters) 2021年第9期34卷 1285-1295页

作者： Hui-Hu Lu xing-Quan shen Wei Liang School of Mechanical Engineering North University of ChinaTaiyuan 030051China College of Materials Science and Engineering Taiyuan University of Technology3 Xueyuan RoadTaiyuan 030024China

A 27.6Cr-3.6Mo-2Ni alloy was solution treated and then aged for a long time to study the effect of grain size on precipitation behaviour by using X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The experimental results demonstrated that the average grain size increased from 46.3 ± 6.2 to 101.8 ± 13.5 μm and the grain boundary length per unit area decreased from 3.3 × 10^(4) to 1.7 × 10^(4) m/m^(2) with an increasing annealing temperature from 1100 to 1200 ℃. After ageing at 800 ℃, the σ-phase,χ-phase and Laves phase were observed. As the ageing time increased, the σ-phase notably increased, while the χ-phase and Laves phase gradually decreased before finally vanishing after ageing for 400 h. The σ-phase precipitation kinetics curves consisted of two parts, and the grain size had a significant effect on the first stage of the precipitation curves due to the abundance of nucleation sites in the specimens with finer grains. The Laves phase was transformed from Nb(C,N) particles by Nb diffusion. As the ageing time increased, the ferrite phase decreased due to the transformation of the ferrite phase to the σ-phase, and then C was expelled into the untransformed ferrite grains. Moreover, new Nb(C,N) particles were formed by Nb diffusion from the Laves phase, resulting in the absence of the Laves phase.

关键词： Ferritic stainless steel Grain size Ageing treatment σ-phase precipitation kinetics Laves phase transformation

Multiscale description of molecular packing and electronic processes in small-molecule organic solar cells

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Chinese Chemical Letters 2016年第8期27卷 1453-1463,1471页

作者： xing-xing shen Guang-Chao Han Yuan-Ping Yi Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

This paper summarizes our recent works on theoretical modelling of molecular packing and electronic processes in small-molecule organic solar ***,we used quantum-chemical calculations to illustrate exciton-dissociation and charge-recombination processes at the DTDCTB/C_（60） interface and particularly emphasized the major role of hot charge-transfer states in the exciton-dissociation ***,we systematically analyzed the influence of DTDCTB surfaces with different features on the vacuum vapor deposition growth and packing morphologies of C_（60） via atomistic molecular dynamics simulations,and found that the formation of crystalline fullerene is the result of an integrated impact of stability,landscape,and molecular orientation of the substrate ***,we investigated the impact of different film-processing conditions,such as solvent evaporation rates and thermal annealing,on molecular packing configurations in a neat small-molecule donor material,DPP（TBFu）_2,and discussed the correlation between charge mobility and molecular packing via atomistic simulations in combination with electronic-structure calculations and kinetic Monte Carlo simulations.

关键词： Molecular packing Molecular self-assembly Photo-induced charge transfer Hot charge transfer state Charge transport Organic photovoltaics

A novel algorithm to counter cross-eye jamming based on a multi-target model

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Frontiers of Information Technology & Electronic Engineering 2019年第7期20卷 988-1002页

作者： Zhi-yong SONG xing-lin shen Qiang FU National Key Laboratory of Science and Technology on ATR National University of Defense Technology

Cross-eye jamming is an electronic attack technique that induces an angular error in the monopulse radar by artificially creating a false target and deceiving the radar into detecting and tracking ***,there is no effective anti-jamming method to counteract cross-eye *** our study,through detailed analysis of the jamming mechanism,a multi-target model for a cross-eye jamming scenario is established within a random finite set framework.A novel anti-jamming method based on multitarget tracking using probability hypothesis density filters is subsequently developed by combining the characteristic differences between target and jamming with the releasing process of *** characteristic differences between target and jamming and the releasing process of jamming are used to optimize particle *** identity labels that represent the properties of target and jamming are introduced into the detection and tracking *** release of cross-eye jamming is detected by estimating the number of targets in the beam,and the distinction between true targets and false jamming is realized through correlation and transmission between labels and estimated ***,accurate tracking of the true targets is achieved under severe jamming *** results showed that the proposed method achieves a minimum delay in detection of cross-eye jamming and an accurate estimation of the target state.

关键词： Particle identity labels Probability hypothesis density Cross-eye jamming Anti-jamming Random finite set Monopulse radar

Nonlinear hysteresis identification and compensation based on the discrete Preisach model of an aircraft morphing wing device manipulated by an SMA actuator

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Chinese Journal of Aeronautics 2019年第4期32卷 1040-1050页

作者： Yuchen CHEN xing shen Jiefeng LI Jinjin CHEN State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics

The conception of aircraft morphing wings thrives in aeronautics since the appearance of shape memory alloys(SMAs). An aircraft morphing wing device, manipulated by an SMA actuator, inherits the intrinsic nonlinear hysteresis from the SMA actuator, ending up with control disadvantages. Conventionally, systems with SMA actuators are constrained to bi-stable states to bypass the hysteresis region. Rather than retreating a morphing wing device to bi-stable states, this paper is dedicated to transcend the morphing wing device beyond the customary limit. A methodology of discrete Preisach modeling, which identifies the hysteresis of the morphing wing device, is proposed herein. An array of discrete equal-distance points is applied to the Preisach plane in order to derive the Preisach density over the partitioned unit of the Preisach plane. Discrete Preisach modeling is fulfilled by the discrete first-order reversible curve(DFORC). By utilizing the discrete Preisach model, the aircraft morphing wing device is simulated; the validity and accuracy of discrete Preisach modeling are demonstrated by contrasting the simulated outcome with experimental data of the major hysteretic loop and the wingspan-wise displacement over time; a comparison between simulation and experimental results exhibits consistency. Afterwards, a hysteresis compensation strategy put forward in this paper is implemented for quasi-linear control of the aircraft morphing wing device, which manifests a compensated shrinking hysteresis loop and attains the initiative of extending the morphing range to the intrinsic hysteretic region.

关键词： Actuator Compensation Hysteresis Morphing wing Preisach model Shape memory effect

重组荔枝类甜蛋白的高效表达、纯化及活性鉴定

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食品与发酵工业 2024年第9期50卷 92-98页

作者：曹琳彩文舜华王凯刘旭炜胡卓炎赵雷沈兴华南农业大学食品学院广东广州510642

荔枝类甜蛋白(litchi thaumatin-like protein,LcTLP)是导致部分人群过量食用荔枝引起机体炎症反应的主要原因之一,为深入探究其引起的机体炎症机制,揭示其晶体结构与促炎活性位点等生物学特性,需获得大量高纯度LcTLP。然而现有报道中... 详细信息

荔枝类甜蛋白(litchi thaumatin-like protein,LcTLP)是导致部分人群过量食用荔枝引起机体炎症反应的主要原因之一,为深入探究其引起的机体炎症机制,揭示其晶体结构与促炎活性位点等生物学特性,需获得大量高纯度LcTLP。然而现有报道中鲜见大量获取高纯度可溶性LcTLP的提取方法,因此该研究对LcTLP基因进行密码子优化后构建了表达载体pCold-NusA-LcTLP,并成功表达了可溶重组蛋白NusA-LcTLP。通过亲和层析与凝胶过滤层析两步纯化法,最终得到的重组蛋白产量可达36.26 mg/L,纯度达90%以上,表明该纯化方案可高效制得高纯度重组LcTLP。经RAW264.7细胞炎症活性验证,重组LcTLP在1、2μg/mL时刺激细胞NO分泌量分别为12.75、14.68μmol/L,为空白组的2.91、3.36倍,验证了重组LcTLP具有一定的促炎活性。该表达载体与纯化方案高效表达得到了可溶性重组LcTLP,为后续深入研究LcTLP在细胞生命活动中的功能机制奠定了基础。

关键词：荔枝重组类甜蛋白诱导表达纯化活性鉴定

Entanglement and Energy for Vibrationally Localized States in Molecule CS2

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Chinese Journal of Chemical Physics 2015年第3期28卷 295-298,I0001页

作者： Zi-xin Yang xing shen Xi-wen Hou Department of Physics Huazhong Normal University Wuhan 430079 China

The dynamics of quantum entanglement described by the yon Neumann entropy is studied for the localized states of Fermi-resonance coupling vibrations in molecule CS2, where the interacting energy between the stretching and the bending modes is considered to establish a connection between entanglement and energy. It is shown that entanglement reveals dominant anti-correlation with the interacting energy for the stretch-localized state, while that exhibits dominantly positive correlation for the bend-localized state. The entanglement and the energy for the dislocalized states are discussed as well. Those are useful for molecular quantum computing and quantum information in high dimensional states.

关键词： Entanglement Quantum entropy Vibrational analysis

Dynamical Running Mass of Quark in the Dyson-Schwinger Equation Approach

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Communications in Theoretical Physics 2002年第5期38卷 571-576页

作者： MA Wei-xing shen Peng-Nian ZHOU Li-Juan Institute of High Energy Physics the Chinese Academy of Sciences Beijing 100039 China Institute of Theoretical Physics the Chinese Academy of Sciences Beijing 100080 China Department of Information and Computing Science Guangxi University of Technology Liuzhou 545006 China Institute of High Energy Physics the Chinese Academy of Sciences Beijing 100039 China Institute of Theoretical Physics the Chinese Academy of Sciences Beijing 100080 China Department of Information and Computing Science Guangxi University of Technology Liuzhou 545006 China

Based on the Dyson-Schwinger equations of QCD in the "rainbow" approximation, the fully dressed quarkpropagator Sf(p) is investigated, and then an algebraic parametrization form of the propagator is obtained as a solutionof the equations. The dressed quark amplitudes Af and Bf built up the fully dressed quark propagator and the dynamicalrunning masses Mf defined by Af and Bf for light quarks u, d and s are calculated, respectively. Using the predictedrunning masses Mf, quark condensates = -(0.255 GeV)a for u, d quarks, and = 0.8<0|q(0)q(0)]0)for s quark, and experimental pion decay constant fπ = 0.093 GeV, the masses of Goldstone bosons K, π, and η are alsoevaluated. The numerical results show that the masses of quarks are dependent on their momentum p2. The fully dressedquark amplitudes Af and Bf have correct behaviors which can be used for many purposes in our future researches onnonperturbative QCD.

关键词： Dyson-Schwinger equations, quark propagator, quark mass, the masses of Goldstone bosons

U.S. national parks accessibility and visitation

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Journal of Mountain Science 2019年第12期16卷 2894-2906页

作者： shen xing-ju HUANG Rui-hong ZHANG Jin-shan College of Historical Culture&Tourism Southwest Minzu UniversityChengdu 610041China Department of Geography Planningand RecreationNorthern Arizona UniversityFlagstaffAZ 86011-5016USA Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Accessibility is a factor affecting national park ***,the effect of accessibility on national park visitation is not fully *** paper examines the relationship between *** park visitation and ***,the global and local accessibility indexes of each park unit are computed based on an accessibility model that takes into account the surrounding population and its proximity to the park *** in the model is a distance decay coefficient that is derived from *** park visitor surveys and therefore pertinent to the case of *** correlation analysis is performed between park visitation and accessibility based on park types,regions,and visitation *** show that total visitation is positively related to accessibility in National Memorials,Military Parks and Battlefield Parks/Sites but negatively related to accessibility in national parks and national ***,recreational overnight stay visits are commonly negatively correlated to accessibility for almost all park ***,local accessibility index displays enhanced correlation coefficients with improved significance levels in many categories of *** suggest that historical/cultural national parks which often show positive correlations tend to attract more local visitors,but nature-based parks which mainly show negative correlations tend to attract more distant visitors.

关键词： U.S.National Park Accessibility Visitation Distance decay GIS