Influence of core property on multi-electron process in slow collisions of isocharged sequence ions with neon

Influence of core property on multi-electron process in the collisions of q = 6-9 and 11 isocharged sequence ions with Ne is investigated in the keV/u region. The cross-section ratios of double-, triple-, quadruple- and total multielectron processes to the single electron capture process as well as the partial ratios of different reaction channels to the relevant multi-electron process are measured by using position-sensitive and time-of-flight techniques. The experimental data are compared with the theoretical predictions including the extended classical over-barrier model, the molecular Columbic barrier model and the semi-empirical scaling law. Results show a core effect on multi-electron process of isocharge ions colliding with Neon, which is consistent with the results of Helium we obtained previously.

Analysis of application range of simplified models for field to thermo-field to thermionic emission processes from the cathode

Electron emission plays a dominant role in plasma-cathode interactions and is a key factor in many plasma phenomena and industrial applications.It is necessary to illustrate the various electron emission mechanisms and the corresponding applicable description models to evaluate their impacts on discharge properties.In this study,detailed expressions of the simplified formulas valid for field emission to thermo-field emission to thermionic emission typically used in the numerical simulation are proposed,and the corresponding application ranges are determined in the framework of the Murphy-Good theory,which is commonly regarded as the general model and to be accurate in the full range of conditions of the validity of the theory.Dimensionless parameterization was used to evaluate the emission current density of the Murphy-Good formula,and a deviation factor was defined to obtain the application ranges for different work functions(2.5‒5 eV),cathode temperatures(300‒6000 K),and emitted electric fields(10^(5) to 10^(10) V·m^(-1)).The deviation factor was shown to be a nonmonotonic function of the three parameters.A comparative study of particle number densities in atmospheric gas discharge with a tungsten cathode was performed based on the one-dimensional implicit particle-in-cell(PIC)with the Monte Carlo collision(MCC)method according to the aforementioned application ranges.It was found that small differences in emission current density can lead to variations in the distributions of particle number density due to changes in the collisional environment.This study provides a theoretical basis for selecting emission models for subsequent numerical simulations.

Corrosion behavior of electron beam processed AZ91 magnesium alloy

The increasing use of light alloys owing to their high performance makes magnesium alloys very attractive for the use in automotive and biomedical applications.However,it is well known that magnesium and its alloys have poor corrosion resistance in different atmospheric and aqueous environments.As a means of improving corrosion resistance through the microstructure modification,electron beam processing(EBP)was applied on the as-cast AZ91 magnesium alloy.To evaluate the microstructure influence on the corrosion-resistant,the EB processed samples underwent a solution heat treatment and an artificial aging heat treatment.Four different obtained microstructures were investigated by standard microscopy and electrochemical corrosion tests to evaluate the microstructure and its effects on the corrosion resistance of AZ91 alloy.The EBPed specimens show a significant microstructure refinement and homogenous distribution ofβ-phase at the grain boundaries surrounded by supersaturatedα-Mg which acts as a barrier against corrosion.The electrochemical corrosion test of the samples immersed in 3.5 wt%NaCl after 4 weeks indicates that the EBP improves the corrosion resistance of the alloy due to the nobler corrosion potential of supersaturated a-Mg and more stable protective hydroxide films compared to the heat-treated and as-cast conditions.

Nonadiabatic Effect on the Rescattering Trajectories of Electrons in Strong Laser Field Ionization Process

The important features of the rescattering trajectories in strong field ionization process such as the cutoff of the return energy at 3.17Up and that of the final energy at 10Up are obtained, based on the adiabatic approximation in which the initial momentum of the electron is assumed to be zero. We theoretically study the nonadiabatic effect by assuming a nonzero initial momentum on the rescattering trajectories based on the semiclassical simpleman model. We show that the nonzero initial momentum will modify both the maximal return energy at collision and the final energy after backward scattering, but in different ways for odd and even number of return trajectories. The energies are increased for even number of returns but are decreased for odd number of returns when the nonzero （positive or negative） initial momentum is applied.

Effect of Valence Electron Structure on Temper Process and Hardness of the Supersaturated Carburized Layer

By measuring the hardness of carburized layer of a new type supersaturated carburizing steel （35Cr3SiMnMoV） at different temper temperature for 2 h, the relationship curve between the carburized layer hardness and the temper temperature is established. The result indicates that the hardness goes down firstly, then up and down, just like a wave consistent with the temperature increase. A secondary hardening peak appears at 570 ℃ or so. Based on Empirical Election Theory （EET） of Solids and Molecules, the valence electron structures （VESs） containing α-Fe-C, α-Fe-C-Me segregation structure units and carbide are calculated. The laws of temper process and hardness change with the temper temperature are explained, and the fact that reconstruction of θ-Fe3C is prior to that of special carbide at high tempering is analyzed with the phase structure formation factor, S, being taken into consideration. Therefore, the laws of temper process and hardness change of supersaturated carburized layer at different temper temperature can be traced back to valence electron structure （VES） level of alloy phase.

Investigation of the degradation rate of electron beam processed and friction stir processed biocompatible ZKX50 magnesium alloy

Together with the mechanical properties,the degradation rate is an important factor for biodegradable implants.The ZKX50 Mg alloy is a suitable candidate to be used as a biodegradable implant due to its favorable biocompatibility and mechanical properties.Current research investigates the degradation rate and corrosion behavior of the ZKX50 as a function of the microstructure constituents and their morphology.Since grain refinement is the main strengthening mechanism for the ZKX50,the effect of the microstructure refinement on the corrosion rate was studied by applying electron beam processing(EBP)and friction stir processing(FSP)on the ZKX50 cast alloy.To study the effect of the microstructure constituents and their morphology a subsequent solution heat treatment(HT)was applied to the processed samples.The results show that the EBP and FSP lead to a uniform and remarkably refined microstructure of the ZKX50 alloy and homogeneous distribution of the intermetallic phases.The results of electrochemical corrosion tests together with the microstructure characterization show that microgalvanic corrosion is the predominant mechanism that occurs between the Ca2Mg6Zn3 intermetallic phase andα-Mg matrix.According to the results attained through the electrochemical tests,the EBPed-HT ZKX50 alloy shows higher corrosion resistance compared to all other conditions immersed in 0.5 wt.%NaCl solution.The dissolution and spheroidizing of Ca2Mg6Zn3 particles during the solution heat treatment provides higher corrosion resistance mainly by decreasing the microgalvanic corrosion.The microstructure of the heat-treated samples does not show a significant grain coarsening which can degrade the enhancement of the mechanical properties achieved by the EBP and FSP.

Laser/Electron Beam Processing of As-cast Nd_2Fe_(14)B Alloy

It was found that the free Fe in the melted zone of the as—cast Nd_2Fe_(14)B alloy could be dissolved by Iaser/electron beam.The growth direction of Nd_2Fe_(14)B grains is nearly perpendicular to the sur- face of the samples.EDX examination showed that Fe element was homogeneously distributed in the melted zone.Results presented in this paper have giv- en hint to remove free Fe in as—cast Nd_2Fe_(14)B alloy.

Electron excitation processes in low energy collisions of hydrogen-helium atoms

The electron excitation processes of H(1s)+He(1s^(2))→H(2s/2p)+He(1s^(2))are studied in impact energy range of 20-2000 e V/u by using the quantum-mechanical molecular orbital close-coupling(QMOCC)method.Total and state-selective cross sections have been obtained and compared with the available theoretical and experimental results.The results agree well with available measurements in the overlapping energy regions overall.The comparison of our results with other theoretical calculations further demonstrates the importance of considering a sufficient number of channels.The datasets presented in this paper,including the excitation cross sections,are openly available at https://www.doi.org/10.57760/sciencedb.j00113.00083.

Experimental observations of the characteristics of hot electron and nonlinear processesproduced in special material

Making use of disk targets composed of several peculiar materials (foamAn, foam C8H8) and hohlraum with a special structure, experiments have been doneat "Xing Guang - II" laser facility, which study the characteristics of hot electronsand the related nonlinear processes such as Stimulated airman Scattering (SRS), TwoPlasma Decay (TPD), Stimulated Brillouin Scattering (SBS), etc.

Detection and processing of molten-pool image of electron-beam deep-penetration welding based on visual sensing

A visual sensing system was developed. The system is suitable for titanium-alloy electron-beam welding, and senses and detects molten-pool dynamic processes. A suite of processing programs for colored molten-pool images in titanium-alloy electron-beam welding was developed using Matlab software; molten-pool edge images are completely obtained using the program. The Matlab software was used to write a program which could extract the molten-pool width. The functional relationship between the molten-pool width and penetration under the experimental conditions was obtained by a curve-fitting method, and provided the theoretical basis for further penetration control.

基于加速退化试验的漏电信号调理电路性能退化及可靠性研究

在电子电路服役过程中,元器件退化会引起电路输出特性变化,降低电子电路的可靠性。漏电信号调理电路作为一种电子电路,其可靠性直接决定了漏电断路器的可靠性。以漏电信号调理电路为研究对象,首先基于灵敏度分析方法确定影响电路性能退化的关键元器件,并对漏电信号调理电路进行了以温度为加速应力、动作电流值为退化特征量的恒定应力加速退化试验;其次根据不同温度应力下的试验数据建立基于Wiener过程的漏电信号调理电路性能退化模型,并利用极大似然估计法求取退化模型的未知参数,进而得出寿命预测的概率密度函数和可靠度函数;最后利用阿伦尼斯(Arrhenius)方程外推出正常应力下漏电信号调理电路的预测寿命。相关结论可为不同电子电路的寿命预测及可靠度分析提供支撑。

IgM沉积强度对原发性IgA肾病患者肾小球超微结构及临床病理的影响

目的探讨原发性IgA肾病(IgA nephropathy,IgAN)患者不同IgM沉积强度与肾小球超微结构病变及临床病理的关系。方法收集155例IgAN患者的临床病理资料。分为IgM阴性(51例)、轻度(89例)和中度及以上沉积(15例)3组。比较3组间肾小球超微特征性结构、临床指标、MEST-C评分差异并分析与IgM沉积强度的影响因素。结果与IgM阴性、IgM轻度沉积组相比,IgM中度及以上沉积组24 h尿蛋白水平、IgG沉积、肾小管萎缩/间质纤维化(T)评分、足突融合(foot process effacement,FPE)程度更高,血白蛋白水平、淋巴细胞计数更低(P<0.05)。logistic结果显示FPE程度、T评分是IgM沉积强度的独立影响因素。结论IgM沉积强度与原发性IgAN患者FPE程度相关。FPE程度可协同临床病理评分更精准评估肾组织损伤及制定治疗方案。

“亮码办”在不动产登记平台中的设计与实现

身份证明是不动产登记受理的必要材料。为深化落实广州市优化营商环境5.0的要求,解决企业或个人未携带实体身份证明造成的困扰和不便等问题,广州市不动产登记率先提出应用电子身份证“亮码办”。平台采用人脸识别和电子身份二维码二次加解密技术,实现了申请人持手机出具身份证明二维码以代替实体身份证明并办理不动产登记业务,达到了政务服务减材料的成效,为企业和群众带来了良好的体验感,同时也为其他地区不动产统一登记平台建设以及推广电子身份证应用提供借鉴。

公立医院政府采购组织与管理现状调研

目的:调研公立医院政府采购现状与组织管理政策,以提高政府采购规范化管理水平。方法:采用电子问卷调查方式收集到全国216所公立医院(涉及28个省市自治区)的政府采购组织与管理现状信息进行调研,分析公立医院政府采购管理的组织结构管理体系、工作模式、监督评价、预算立项、招标采购、合同签订、验收流程、付款管理等现状。结果:调查问卷共回收216份(216所医院)有效问卷,其中综合医院、专科医院和中医医院分别为165、37和13所,分别占76.39%、17.13%和6.02%;医院级别中三级医院202所(占93.52%)。被调查公立医院政府采购管理机构中采购管理委员会、采购管理办公室、采购中心和业务及行政后勤部门4层组织机构分别为112、103、110和112个,分别占51.85%、47.69%、50.93%和51.85%;所有医院政府采购公开招标限额标准均符合国家法规要求;各医院付款必须条件的资金审批情况均符合要求;医院风险防控管理效果中非常好、良好、一般和不到位4种情况分别为48、125、34和9所,分别占22.22%、57.87%、15.74%、4.17%。结论:公立医院政府采购的组织框架与管理体系日趋规范,不同医院政府采购工作模式与流程存在一定差异,监管评价相对薄弱值得关注和加强管理。

适用于共晶焊的肖特基二极管背面金属化工艺优化

[目的]为了降低成本,减少污染,提高工艺效率,对肖特基二极管背面金属化工艺进行研究,探索锡锑合金替代金系合金的最佳不持温镀膜金属化工艺.[方法]通过持温镀膜与不持温镀膜对比实验,分析电子束蒸发镀膜基片温度对阴极金属层间黏附性和导电性,以及薄膜厚度对空洞率的影响,得到适用于批量共晶焊的肖特基二极管背面金属化最优工艺参数.[结果]当基片温度为180℃时,不持温镀膜的剪切力为64.53 N,高于持温镀膜的剪切力;当金属化锡锑合金膜厚为3μm时,共晶焊的空洞率低于5%,符合共晶焊要求;电子束蒸发镀膜背面金属层方块电阻随基片温度升高先减小后增大,温度在180~240℃之间,方块电阻随基片温度的变化不大.[结论]用于共晶焊的肖特基二极管背面金属化的最优工艺为基底温度升到180℃后在自然降温的同时进行多层金属镀膜,锡锑合金镀膜厚度为3μm.

基于熵权法-AHP法的高能电子束辐照对生附片品质影响分析

为探究高能电子束辐照对生附片灭菌效果及药材品质的影响,本试验采用0、1、3、5、7、10、13、15和25 kGy剂量的电子束对生附片进行辐照处理,分析贮藏期内微生物数量和理化指标的变化。结果表明,辐照剂量为1 kGy可将微生物负载超标样品中的需氧菌总数、霉菌和酵母菌总数降至标准规定以下。不同辐照剂量下的水分、总灰分和浸出物含量均无显著差异(P>0.05);总色差值(ΔE)随辐照剂量的增加而显著增加。经7、10、13 kGy高能电子束辐照处理后,总生物碱、单双酯型生物碱含量总和低于未辐照组。1,1-二苯基-2-三硝基苯肼(DPPH)清除率随辐照剂量增加整体显著下降(P<0.05)。高效液相色谱(HPLC)指纹图谱显示,不同辐照剂量高能电子束处理样品的相似度大于0.97,质量较稳定。熵权法结合层次分析法(AHP)综合评价表明,5 kGy辐照组的品质综合评分最高,1 kGy辐照组的品质综合评分最低。本研究结果可为高能电子束辐照技术在生附片及其加工品贮藏中的应用提供理论参考。

三极管共射放大实验电路频率特性的测试与分析

三极管共射放大电路实验是模拟电子技术基本实验之一,实验前基于Multisim波特图得到幅频特性及相频特性曲线。经与理论分析对照,有两个现象:一是上限截止频率远大于理论估算值;二是相频特性曲线在中频段某频率点发生-180°到180°相位跳变。针对第一个现象,实验后对测试数据利用Python进行处理,表明幅频特性下限频率点理论值、仿真值与测试值基本一致;上限频率点介于理论值与仿真值之间。针对第二个现象,经Python绘制了理论相频特性曲线,用示波器实测输入、输出信号的李莎如图形,表明没有相位的跳变。

基于NLP构建病历后结构化专病数据库探索与实践

目的/意义建设基于结构化电子病历的专病数据库,提高专病数据库规范性和可用性,提高临床科研工作效率。方法/过程采用模板化输入、自然语言处理等技术,将非结构化电子病历转化为结构化电子病历,基于结构化电子病历构建专病数据库。结果/结论龙华医院基于结构化电子病历建设的银屑病专病数据库分中心,为临床科研人员提供结构化科研数据源,辅助提升分析效率;同时有效支撑上海申康“基于多中心的银屑病专病大数据临床科研随访一体化平台”建设,有助于专病数据库高质量、规模化发展。

人工智能驱动档案数据智治探索——基于智慧医疗档案管理“提智增效”的考察

在数字化、网络化日益普及的今天,档案数据已不再是孤立、静态的信息孤岛,而是需要与其他数据资源进行整合、关联和共享的重要资产。本研究将关注人工智能技术在实现医疗档案数据与其他数据资源的互联互通、共建共享方面的作用和价值,探索构建基于人工智能的档案数据智治新模式。对人工智能在档案数据管理和应用中可能带来的挑战和风险进行深入剖析,并提出相应的应对策略和解决方案。

数字信号处理技术在电子信息工程中的应用

随着信息技术的快速发展和应用领域的不断扩展,数字信号处理技术在电子信息工程中的应用越来越广泛。例如,在人工智能、机器学习、深度学习和计算机视觉等领域。文中首先介绍了数字信号处理技术的优点,包括高效的数据处理能力、可控的实现过程和高度集成的特点。接着,阐述了数字控制系统的设计和实现过程。最后,分析了基于DSP控制器架构下PWM整流数字信号的仿真控制。