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A characterization study on perovskite X-ray detector performance based on a digital radiography system

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Nuclear Science and Techniques 2023年第5期34卷 56-66页

作者： Yang wang Qiong Zhang University of Electronic Science and Technology of china Chengdu 610000China

X-ray imaging technologies such as digital radiography(DR),is an important aspect of modern non-destructive testing and medical *** flexible X-ray detector technologies have recently been proposed and are now receiving increasing attention owing to their superior material flexibility compared with traditional flat-panel *** work aims to study these innovative flexible X-ray detectors in terms of their effectiveness in DR imaging,such as detection efficiency and spatial *** achieve this goal,first,a Monte Carlo model was developed and calibrated to an in-lab 150 kV DR imaging system containing a flat-panel X-ray ***,the validated model was updated with various types of flexible X-ray detectors to assess their performance in nearly realistic *** parameters such as the detection efficiency pertaining to the crystal material and thickness were studied and analyzed across a broader energy range up to 662 ***,the imaging performance of the different detectors was evaluated and compared to that of the flat-panel detector in the 150 kV DR imaging *** results show that the flexible detectors such as the CsPbBr3crystal detector deliver promising performance in X-ray imaging and can be applied to a wider range of application scenarios,especially those requiring accurate detection at challenging angles.

关键词： Flexible X-ray detector DR imaging system Monte Carlo simulation

International Meridian Circle Program

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空间科学学报 2020年第5期40卷 723-725页

作者： LIU William wang chi SHEN Xuhui WU Jian BLANC Michel YAN Yihua FU Suiyan YUE Xinan LEI Jiuhou GONG Wei ZHANG Shaodong ZHANG Qinghe wang Xin YANG Jing ZHANG Xiaoxin GAO Jing XU Jiyao YANG Guotao LI Hui REN Liwen YANG Fang National Space Science Center Chinese Academy of SciencesBeijing 100190 National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085 china Electronics Technology Group Corporation No.22 Research Institute Xinxiang 259008 National Astronomical Observatories Chinese Academy of SciencesBeijing 100101 School of Earth and Space Sciences Peking UniversityBeijing 100871 Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100083 School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026 School of Electronic Information Wuhan UniversityWuhan 430079 School of Space Science and Physics Shandong UniversityWeihai 264209 Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029 china Meteorological Administration Beijing 100089 Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101

The Earth is buffered from the ferocious onslaught of the solar wind by a thin layer of matter known as the atmosphere and *** layer absorbs energy from irradiance and outburst from the Sun,as well as from disasters,transient phenomena and anthropogenic emissions originated from *** complicated physics,the absorbed energy changes the atmospheric and geospace state and sometimes gets re-released to power extreme events such as space *** place globally,these complicated processes cannot be understood unless they are studied *** chinese scientists have proposed the International Meridian Circle Program(IMCP)to meet this *** operating nearly 1000 instruments encompassing all latitudes along with the 120°E–60°W longitudes,IMCP aims,for the first time,to construct comprehensive 3D data representation of the atmosphere and geospace on a global scale and empower interdisciplinary research to tackle key questions related to Earth’s environment and climate change.

关键词： International Meridian Circle Program chinese Meridian Project Ground-based observation Space weather Solar-terrestrial physics

Optimizing mechanical properties of magnesium alloys by philosophy of thermo-kinetic synergy:Review and outlook

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Journal of Magnesium and Alloys 2022年第2期10卷 346-383页

作者： Tianle wang Feng Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’anShaanxi 710072China Analytical&Testing Center Northwestern Polytechnical UniversityXi’anShaanxi 710072China

Although several strategies(including grain refinement,texture adjustment,precipitation hardening,etc.)have been verified to effectively improve the mechanical properties of lightweight magnesium(Mg)alloys,considerable efforts are still needed to be made to comprehensively understand the potential mechanisms controlling complex microstructures and deformation behaviors exhibited by the hexagonal close-packed host lattice of Mg,thus assisting the rational design of materials at a more physical *** the cornerstone of this review,a universal rule,the so-called synergy of thermodynamics and kinetics(i.e.,thermo-kinetic diversity,correlation and connectivity),including a recently proposed theory of generalized stability(GS),is introduced to deepen our understanding on common behaviors in Mg alloys(i.e.,deformations(slip and twining modes),phase transformations(especially for precipitations)and interactions in between)at a new *** by the GS theory,typical cases for Mg alloys design are qualitatively evaluated to reemphasize the traditional strengthening and toughening strategies mentioned above and to illuminate their exquisite coordination for breaking through the trade-off relationship between strength and ductility,corresponding to a typical thermo-kinetic pair(i.e.,high driving force(ΔG)-high GS).To produce the Mg alloys with superior strength-ductility balances,the potential capacity of this GS theory for guiding processing path design is discussed,finally。

关键词： Magnesium alloys Synergy of thermodynamics and kinetics Generalized stability Superior strength-ductility balance

Physical and Mechanical Properties of Catalpa bungei Clones and Estimation of the Properties by Near-Infrared Spectroscopy

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Journal of Renewable Materials 2022年第12期10卷 3285-3302页

作者： Rui wang Lanlan Shi Yurong wang Research Institute of Wood Industry Chinese Academy of ForestryBeijing100091China

Air-dry density,modulus of rupture(MOR),modulus of elasticity(MOE),compressive strength parallel to grain,and hardness of Catalpa bungei clones were investigated in this study with feasibility of predicting these properties by near infrared(NIR)*** best candidate Luoqiu 3'has been selected from three clones based on wood physical and mechanical property *** values of wood physical and mechanical properties have been found in the corewood compared to the *** were significant positive correlations between the air-dry density and mechanical *** from Cross section for air dry density,compressive strength parallel to grain,and hardness yielded prediction models with better effects,along with the best MOR and MOE modeling effects resulted from average sections'spectra *** scatter correction(MSC)+Savitzky-Golay(S-G)smoothing method has been proved to be the most applicable *** addition,the predictions from five point sampling method were slightly better than three point ***,results suggest NIR spectroscopy was viable to predict the physical and mechanical properties of C bungei dones with methods developed in this study proved effective in preliminary screening.

关键词： C.bungei wood density mechanical properties near-infrared spectroscopy

Modular Invariance and Anomaly Cancellation Formulas

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Acta Mathematica Sinica,English Series 2011年第7期27卷 1297-1304页

作者： Yong wang School of Mathematics and Statistics Northeast Normal University Changchun 130024 P. R. China

By studying modular invariance properties of some characteristic forms, we get some new anomaly cancellation formulas. As an application, we derive some results on divisibilities on spin manifolds and congruences on s... 详细信息

关键词： Modular invariance cancellation formulas divisibilities

Optimized transition metal-oxygen covalency promotes neutral-pH oxygen evolution catalysis

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Science china Materials 2022年第11期65卷 3182-3183页

作者： Xun wang Laboratory of Organic Optoelectronics and Molecular Engineering Department of ChemistryTsinghua UniversityBeijing 100084China

Water electrolysis using renewable electricity provides an emission-free route to produce hydrogen in a green manner[1].Neutral-pH water splitting could avoid the corrosion problem and offer a benign environment to expand the choice of catalysts and bipolar plates[2].However,a substantial overpotential is generally required due to the sluggish kinetic process for anodic oxygen evolution reaction(OER).Although Ru and Ir-based noble metals have fast OER kinetics,their high cost and limited resources impede their large-scale ***,developing more active catalysts with low cost for neutral-pHOER becomes important yet challenging.

关键词： neutral catalysis kinetics

A Machine Learning Method for Differentiating and Predicting Human-Infective Coronavirus Based on Physicochemical Features and Composition of the Spike Protein

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chinese Journal of Electronics 2021年第5期30卷 815-823页

作者： wang Chao ZOU Quan Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Hainan Key Laboratory for Computational Science and Application Hainan Normal University

Several Coronaviruses(CoVs) are epidemic pathogens that cause severe respiratory syndrome and are associated with significant morbidity and mortality. In this paper, a machine learning method was developed for predicting the risk of human infection posed by CoVs as an early warning system. The proposed Spike-SVM(Support vector machine) model achieved an accuracy of 97.36% for Human-infective CoV(HCoV) and Nonhuman-infective CoV(Non-HCoV) classification. The top informative features that discriminate HCoVs and Non-HCoVs were identified. Spike-SVM is anticipated to be a useful bioinformatics tool for predicting the infection risk posed by CoVs to humans.

关键词： Spike protein NonHCoVs genetics microorganisms Support vector machine mortality Spike-SVM model Human-infective CoV severe respiratory syndrome machine learning method biology computing predicting Human-infective coronavirus diseases proteins HCoV human infection differentiating Nonhuman-infective CoV infection risk CoVs discriminate HCoVs learning (artificial intelligence) bioinformatics support vector machines informative features significant morbidity molecular biophysics early warning system epidemic pathogens Coronaviruses

Research of Neural Network Structural Optimization Based on Information Entropy

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chinese Journal of Electronics 2020年第4期29卷 632-638页

作者： wang Danyang SHAO Fangming School of Science East China University of Science and Technology

In the application of deep learning, the depth and width of the neural network structure have a great influence on the learning performance of the neural *** paper focuses on structural optimization of depth and width, leveraging the information entropy model and decision tree strategy as feature selection and structural adjustment to optimize neural network ***, a decision tree-based heuristic optimization algorithm for neural network structural adjustment is ***, the proposed approach is applied to fully-connected neural networks trained on the Iris dataset, and the proposed approach is verified effective via experimental simulation.

关键词： Information entropy Decision tree Fully connected neural network Heuristic algorithm

Numerical study on the morphology of a liquid-liquid pintle injector element primary breakup spray

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2020年第8期21卷 684-694页

作者： Rui ZHOU chi-bing SHEN Xuan JIN Science and Technology on Scramjet Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

Primary breakup in a liquid-liquid pintle injector element at different radial jet velocities is investigated to elucidate the impingement morphology,the formation of primary breakup spray half cone angle,the pressure distribution,the liquid diameter distribution,and the liquid velocity *** a sufficient mesh resolution,the liquid morphology can be captured in a physically sound way.A mushroom tip is triggered by a larger radial jet velocity and breakup happens at the tip edge *** kinds of ligament breakup patterns due to aerodynamic force and surface tension are captured on the axial sheet.A high pressure core is spotted at the impinging point region.A larger radial jet velocity can feed more disturbances into the impinging point and the axial sheet,generate stronger vortices to promote the breakup process at a longer distance,and form a larger spray half cone *** of the re-collision phenomenon the axial sheet diameter does not decrease *** inner rim on the axial sheet shows a larger diameter magnitude and a lower velocity magnitude due to surface *** paper is expected to provide a reference for the optimum design of a liquid-liquid pintle injector.

关键词： Pintle injector element Liquid-liquid impingement Primary breakup Volume of fluid-to-discrete phase model(VOF-to-DPM)simulation Adaptive mesh refinement(AMR)method