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Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

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Optoelectronics Letters 2008年第4期4卷 299-301页

作者： SHI Jun XIAO Sha-li WANG Hong-jian TANG Chang-huan liu shen-ye The Key Laboratory of Optoelectronic Technology and System Ministry of Education Chongqing University Chongqing 400030 China Research Center of Laser Fusion China Academy of Engineering Physics Mianyang 621900 China

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200）（2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S^1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.

关键词：弯晶分光计 X射线激光等离子体测量方法

Locating Sources of Oscillations Induced by Control of Voltage Source Converters Based on Energy Structure and Nonlinearity Detection

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1285-1294页

作者： Zetian Zheng Shaowei Huang Jun Yan Qiangsheng Bu Chen shen Mingzhong Zheng ye liu State Key Laboratory of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China State Grid Jiangsu Electric Power Co. Ltd.Research InstituteNanjing 211103China

The oscillation phenomena associated with the con-trol of voltage source converters(VSCs)are concerning,mak-ing it crucial to locate the sources of such oscillations and sup-press the ***,this paper presents a location scheme based on the energy structure and nonlinearity *** energy structure,which conforms to the principle of the energy-based method and dissipativity theory,is developed to describe the transient energy flow for VSCs,based on which a defined characteristic quantity is implemented to narrow the scope for locating the sources of ***,based on the self-sustained oscillation characteristics of VsCs,an in-dex for nonlinearity detection is applied to locate the VSCs that produce the oscillation *** combination of the energy structure and nonlinearity detection distinguishes the contribu-tions of different VSCs to the *** results of a case study implemented by the PSCAD/EMTDC simulation validate theproposed scheme.

关键词： Double-loop proportional-integral(PI)control energy structure Hamiltonian model nonlinearity detection oscillation source location(OSL) voltage source converter(VSC)

SCIRD: Revealing Infection of Malicious Software in Edge Computing-Enabled IoT Networks

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Computers, Materials & Continua 2024年第5期79卷 2743-2769页

作者： Jiehao ye Wen Cheng Xiaolong liu Wenyi Zhu Xuan’ang Wu Shigen shen School of Information Engineering Huzhou UniversityHuzhou313000China

The Internet of Things(IoT)has characteristics such as node mobility,node heterogeneity,link heterogeneity,and topology *** the face of the IoT characteristics and the explosive growth of IoT nodes,which brings about large-scale data processing requirements,edge computing architecture has become an emerging network architecture to support IoT applications due to its ability to provide powerful computing capabilities and good service ***,the defense mechanism of Edge Computing-enabled IoT Nodes(ECIoTNs)is still weak due to their limited resources,so that they are susceptible to malicious software spread,which can compromise data confidentiality and network service *** this situation,we put forward an epidemiology-based susceptible-curb-infectious-removed-dead(SCIRD)***,we analyze the dynamics of ECIoTNs with different infection levels under different initial conditions to obtain the dynamic differential ***,we establish the presence of equilibrium states in the SCIRD ***,we conduct an analysis of the model’s stability and examine the conditions under which malicious software will either spread or disappear within Edge Computing-enabled IoT(ECIoT)***,we validate the efficacy and superiority of the SCIRD model through MATLAB *** research findings offer a theoretical foundation for suppressing the propagation of malicious software in ECIoT *** experimental results indicate that the theoretical SCIRD model has instructive significance,deeply revealing the principles of malicious software propagation in ECIoT *** study solves a challenging security problem of ECIoT networks by determining the malicious software propagation threshold,which lays the foundation for buildingmore secure and reliable ECIoT networks.

关键词： Edge computing Internet of Things malicious software propagation model heterogeneity

Identifying the enhancement mechanism of Al/MoO_(3) reactive multilayered films on the ignition ability of semiconductor bridge using a one-dimensional gas-solid two-phase flow model

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Defence Technology（防务技术） 2024年第3期33卷 168-179页

作者： Jianbing Xu Yuxuan Zhou Yun shen Yueting Wang Yinghua ye Ruiqi shen School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China Micro-Nano Energetic Devices Key Laboratory of MIIT Nanjing 210094China Institute of Space Propulsion Nanjing University of Science and TechnologyNanjing 210094China

Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics *** the ignition enhancement mechanism of RMFs on semiconductor bridge(SCB)during the ignition process is crucial for the engineering and practical application of advanced initiator and pyrotechnics *** this study,a one-dimensional(1D)gas-solid two-phase flow ignition model was established to study the ignition process of ESCB to charge particles based on the reactivity of Al/MoO_(3) *** order to fully consider the coupled exothermic between the RMFs and the SCB plasma during the ignition process,the heat release of chemical reaction in RMFs was used as an internal heat source in this *** is found that the exothermal reaction in RMFs improved the ignition performance of *** the process of plasma rapid condensation with heat release,the product of RMFs enhanced the heat transfer process between the gas phase and the solid charge particle,which accelerated the expansion of hot plasma,and heated the solid charge particle as well as gas phase region with low *** addition,it made up for pressure loss in the gas *** the plasma dissipation process,the exothermal chemical reaction in RMFs acted as the main heating source to heat the charge particle,making the surface temperature of the charge particle,gas pressure,and gas temperature rise *** result may yield significant advantages in providing a universal ignition model for miniaturized ignition devices.

关键词： Ignition enhancement mechanism 1D gas-solid two-phase flow Al/MoO_(3)reactive multilayered films Semiconductor bridge Miniaturized ignition device

Upconversion luminescence and temperature sensing performance of Er^(3+) ions doped self-activated KYb(MoO_(4))_(2) phosphors

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Journal of Rare Earths 2024年第8期42卷 1507-1513,I0004页

作者： ye Tong Wenpeng liu Shoujun Ding School of Microelectronics and Data Science Anhui University of TechnologyMaanshan243002China Advanced Laser Technology Laboratory of Anhui Province Hefei230037China Anhui Institute of Optics and Fine Mechanics Chinese Academy of SciencesHefei230031China

In this work,a series of self-activated KYb(MoO_(4))_(2) phosphors with various x at% Er^(3+) doping concentrations(x=0.5,1,3,5,8,10,15) was synthesized by the solid-state reaction *** phase structure of the as-prepared samples was analyzed by X-ray diffraction(XRD),XRD Rietveld refinement and Fourier transform infrared(FT-IR) *** as-prepared samples retain the orthorhombic structure with space group of Pbcn even Er^(3+) doping concentration up to 15 at%.High-purity upconversion(UC) green emission with green to red intensity ratio of 55 is observed from the as-prepared samples upon the excitation of 980 nm semiconductor laser and the optimum doping concentration of Er^(3+) ions in the self-activated KYb(MoO_(4))_(2) host is revealed as 3 at%.The strong green UC emission is confirmed as a two-photon process based on the power-dependent UC *** addition,the fluorescence intensity ratios(FIRs) of the two thermally-coupled energy levels,namely ^(2)H_(11/2) and ^(4)S_(3/2).of Er^(3+) ions were investigated in the temperature region 300-570 K to evaluate the optical temperature sensor behavior of the *** maximum relative sensitivity(S_(R)) is determined to be 0.0069 K^(-1) at300 K and the absolute sensitivity(S_(A)) is determined to be 0.0126 K^(-1) at 300 *** S_(A) of self-activated KYb(MoO_(4))2:Er^(3+)is almost twice that of traditional KY(MoO_(4))2:Er^(3+)/Yb^(3+)codoping *** results demonstrate that Er^(3+) ions doped self-activated KYb(MoO_(4))2 phosphor has promising application in visible display,trademark security and optical temperature sensors.

关键词： Er^(3+)ions doped KYb(MoO_(4))_(2) Self-activated phosphors Upconversion luminescence Solid-state reaction method Optical temperature sensors Rare earths

Intravitreal conbercept injection with panretinal photocoagulation for high-risk proliferative diabetic retinopathy with vitreous hemorrhage

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1066-1072页

作者： Yao Xu Qing ye Wei shen Department of Ophthalmology the Fourth Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina Department of Ophthalmology Suzhou Kowloon HospitalShanghai Jiao Tong University School of MedcineSuzhou 215000Jiangsu ProvinceChina Department of Ophthalmology the First Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina

AIM:To assess the clinical efficacy and safety of combining panretinal photocoagulation(PRP)with intravitreal conbercept(IVC)injections for patients with high-risk proliferative diabetic retinopathy(HR-PDR)complicated by mild or moderate vitreous hemorrhage(VH),with or without diabetic macular edema(DME).METHODS:Patients diagnosed with VH with/without DME secondary to HR-PDR and received PRP combined with IVC injections were recruited in this retrospective *** establishing the patient’s diagnosis,an initial IVC was performed,followed by prompt administration of *** cases who significant bleeding persisted and impeded the laser operation,IVC was sustained before supplementing with *** the completion of PRP,patients were meticulously monitored for a minimum of six *** therapy and IVC injections were judiciously adjusted based on fundus fluorescein angiography(FFA)*** effect and the incidence of adverse events were ***:Out of 42 patients(74 eyes),29 were male and 13 were female,with a mean age of 59.17±12.74y(33-84y).The diabetic history was between 1wk and 26y,and the interval between the onset of visual symptoms and diagnosis of HR-PDR was *** affected eye received 2.59±1.87(1-10)IVC injections and underwent 5.5±1.02(4-8)sessions of *** these,68 eyes received PRP following 1 IVC injection,5 eyes after 2 IVC injections,and 1 eye after 3 IVC *** absorption of VH was observed in all 74 eyes 5-50wk after initial treatment,with resolution of DME in 51 eyes 3-48wk after initial treatment.A newly developed epiretinal membrane was noted in one *** acuity significantly improved in 25 *** complications such as glaucoma,retinal detachment,or endophthalmitis were ***:The study suggests that the combination of PRP with IVC injections is an effective and safe modality for treating diabetic VH in patients with HR-PDR.

关键词： conbercept panretinal photocoagulation high-risk proliferative diabetic retinopathy vitreous hemorrhage

Highlights of mainstream solar cell efficiencies in 2023

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Frontiers in Energy 2024年第1期18卷 8-15页

作者： Wenzhong shen Yixin ZHAO Feng liu Institute of Solar Energy and Key Laboratory of Artificial Structures and Quantum Control(Ministry of Education)School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China School of Environmental Science and Engineering and Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China School of Chemistry and Chemical Engineering and Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China

This article continues our highlights last two years[1,2]on the highest independently confirmed mainstream(silicon,perovskite,and organic)solar cell efficiencies in *** world record power conversion efficiency(PCE)of the single-junction silicon and perovskite/silicon tandem solar cells has reached over 27%and close to 34%,respectively,in *** have also witnessed the rapid mass-production development of the silicon passivating contact and silicon back contact solar cells,as well as further progress with perovskite solar cells(PSCs).

关键词： perovskite mainstream fir

Effect of reduction pretreatment on the structure and catalytic performance of Ir-In_(2)O_(3)catalysts for CO_(2) hydrogenation to methanol

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Journal of Environmental Sciences 2024年第6期140卷 2-11页

作者： Changyu Ding Feifei Yang Xue ye Chongya Yang Xiaoyan liu Yuanlong Tan Zheng shen Hongmin Duan Xiong Su Yanqiang Huang CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

In_(2)O_(3)has been found a promising application in CO_(2)hydrogenation to methanol,which is beneficial to the utilization of CO_(2).The oxygen vacancy(O_(v))site is identified as the catalytic active center of this ***,there remains a great challenge to understand the relations between the state of oxygen species in In_(2)O_(3)and the catalytic performance for CO_(2)hydrogenation to *** the present work,we compare the properties of multiple In_(2)O_(3)and Ir-promoted In_(2)O_(3)(Ir-In_(2)O_(3))catalysts with different Ir loadings and after being pretreated under different reduction *** CO_(2)conversion rate of Ir-In_(2)O_(3)is more promoted than that of pure In_(2)O_(3).With only a small amount of Ir loading,the highly dispersed Ir species on In_(2)O_(3)increase the concentration of O_(v)sites and enhance the *** finely tuning the catalyst structure,Ir-In_(2)O_(3)with an Ir loading of 0.16 wt.%and pre-reduction treatment under 300℃exhibits the highest methanol yield of 146 mgCH_(3)OH/(gcat·hr).Characterizations of Raman,electron paramagnetic resonance,X-ray photoelectron spectroscopy,CO_(2)-temperature programmed desorption and CO_(2)-pulse adsorption for the catalysts confirm that more O_(v)sites can be generated under higher reduction temperature,which will induce a facile CO_(2)adsorption and desorption *** performance for methanol production requires an adequate dynamic balance among the surface oxygen atoms and vacancies,which guides us to find more suitable conditions for catalyst pretreatment and reaction.

关键词： Carbon dioxide Hydrogenation Methanol In_(2)O_(3) Fixed-bed Reduction temperature

Improved Double Deep Q Network-Based Task Scheduling Algorithm in Edge Computing for Makespan Optimization

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Tsinghua Science and Technology 2024年第3期29卷 806-817页

作者： Lei Zeng Qi liu Shigen shen Xiaodong liu School of Computer Science Nanjing University of Information Science and TechnologyNanjing 210044China School of Software Nanjing University of Information Science and TechnologyNanjing 210044China School of Information Engineering Huzhou UniversityHuzhou 313000China School of Computing Edinburgh Napier UniversityEdinburghEH105DTUK

Edge computing nodes undertake an increasing number of tasks with the rise of business ***,how to efficiently allocate large-scale and dynamic workloads to edge computing resources has become a critical *** study proposes an edge task scheduling approach based on an improved Double Deep Q Network(DQN),which is adopted to separate the calculations of target Q values and the selection of the action in two networks.A new reward function is designed,and a control unit is added to the experience replay unit of the *** management of experience data are also modified to fully utilize its value and improve learning *** learning agents usually learn from an ignorant state,which is *** such,this study proposes a novel particle swarm optimization algorithm with an improved fitness function,which can generate optimal solutions for task *** optimized solutions are provided for the agent to pre-train network parameters to obtain a better cognition *** proposed algorithm is compared with six other methods in simulation *** show that the proposed algorithm outperforms other benchmark methods regarding makespan.

关键词： edge computing task scheduling reinforcement learning makespan Double Deep Q Network(DQN)