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Journal of Rare Earths 2024年第6期42卷 1020-1028,I0001页

作者： Yan Lei Guangzhi Zhang yitong yao Gaiqin Zhu Zhong Chen Jiangrong Dan Hua Liu Shuwang Duo School of Materials and Mechanical and Electrical EngineeringJiangxi Science and Technology Normal University Nanchang330013China

ZnS and ZnS:3.125%Ce^(3+)(ZSC)quantum dots(QDs)were synthesized by a low-temperature solid-phase *** crystal structure,photoluminescence(PL)properties of ZSC QDs,and their effects on the growth and kojic acid production of Aspergillus oryzae(***)were *** is found that both QDs have a cubic blend structure with the average particle size ranging of 2.75-6.14 ***^(3+)doping not only increases the band gap of ZnS QDs from 3.43 to 3.48 eV,but also increases the PL intensity by about 2.23 times,which is due to the fact that the electron carrier concentration is improved,and then the rate of radiative recombination is *** integral emission intensity,biomass,extracellular proteins yield,and kojic acid production of *** cultured with ZSC(ZnS)QDs are about 4.31(3.23),1.61(1.20),1.12(1.09),and 2.99(1.68)times higher than that of medium without QDs,respectively.

关键词： Zns Quantum dots Doping First-principles calculations Aspergllus oryzae Rare earths

Integrated modelling of vacuum flashover development: Above-surface processes and breakdown threshold analyses

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HIGH VOLTAGE 2024年第3期9卷 614-625页

作者： Sun, Guangyu yao, yitong Yang, Xiong Guo, Baohong Zhang, Shu Wang, Chao Lian, Ruhui Song, Baipeng Mu, Haibao Zhang, Guanjun Xi An Jiao Tong Univ Sch Elect Engn State Key Lab Elect Insulat & Power Equipment Xian Shaanxi Peoples R China

The flashover in vacuum is a rapid interfacial discharge across the insulator surface when subjected to high applied voltage. Here a theoretical model covering above-surface processes is introduced. The model calculates the flashover threshold in vacuum, with revised secondary electron emission avalanche theory and improved desorbed neutral transport model. The model serves as the first part of an integrated flashover model, aiming for consistent treatment of both above-surface and subsurface processes during the entire flashover development. The flashover threshold is obtained by combining the desorbed neutral pressure at given applied voltage and the gas breakdown criterion dictated by the Paschen's law. An analytical formula for threshold estimation containing physical parameters, and a simplified formula consisting of empirical coefficients are introduced, catering for both conceptual understanding and practical application. The derived formulae are validated by experimental data for a variety of insulator materials. The theory generalisation for non-uniform electric field distribution is further discussed.

关键词： SECONDARY ELECTRONS INSULATORS EMISSION VOLTAGE FIELD DC

中国肉鸭产业绿色全要素生产率测算及区域差异分析

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中国家禽 2024年第6期46卷 56-64页

作者：姚懿桐林昊刘灵芝唐山工业职业技术学院河北唐山063299 华中农业大学湖北武汉430070

为提高我国24个肉鸭主产省(市、区)的环境技术效率和绿色全要素生产率,研究基于2020和2021年我国24个肉鸭主产省(市、区)的肉鸭养殖投入产出数据,利用超效率SBM模型和ML指数,分别对我国肉鸭产业环境技术效率和绿色全要素生产率进行测算... 详细信息

为提高我国24个肉鸭主产省(市、区)的环境技术效率和绿色全要素生产率,研究基于2020和2021年我国24个肉鸭主产省(市、区)的肉鸭养殖投入产出数据,利用超效率SBM模型和ML指数,分别对我国肉鸭产业环境技术效率和绿色全要素生产率进行测算,将其与不考虑非期望产出的测算结果对比,分析肉鸭产业绿色发展总体情况及省际、区域差异。结果显示:①从环境技术效率来看,我国肉鸭养殖技术效率总体在改善,我国大部分肉鸭主产省(市、区)实现决策充分有效,但存在环境技术投入相对不足问题。环境技术效率呈现东中西递减趋势,北方高于南方,各区域内仍存在产业发展与环境不协调问题,忽视环境约束会使肉鸭养殖效率高估;②从绿色全要素生产率来看,我国肉鸭产业绿色全要素生产率出现增长但整体增长形势并不乐观,产业面临技术进步放缓,增长的动力主要依靠绿色技术效率改善,增长速度也呈现东中西递减趋势,北方高于南方,区域差距体现在绿色技术进步上。研究表明,我国肉鸭产业绿色全要素生产率存在很大提升空间,要从技术创新投入、技术推广入手,因地制宜制定绿色全要素生产率提升策略,发挥环境规制的作用。

关键词：肉鸭环境技术效率绿色全要素生产率超效率SBM 区域差异

Future biomass carbon sequestration capacity of Chinese forests

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Science Bulletin 2018年第17期63卷 1108-1117页

作者： yitong yao Shilong Piao Tao Wang Sino-French Institute for Earth System Science College of Urban and Environmental Sciences Peking University Beijing 100871 China Key Laboratory of Alpine Ecology and Biodiversity Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Center for Excellence in Tibetan Earth Science Chinese Academy of Sciences Beijing 100085. China

Chinese forests, characterized by relatively young stand age, represent a significant biomass carbon （C） sink over the past several decades. Nevertheless, it is unclear how forest biomass C sequestration capacity in China will evolve as forest age, climate and atmospheric CO2 concentration change continuously. Here, we present a semi-empirical model that incorporates forest age and climatic factors for each lbrest type to estimate the effects of forest age and climate change on total forest biomass, under three different sce-narios based on the fifth phase of the Coupled Model Intercomparison Project （CMIPS）. We estimate that age-related forest biomass C sequestration to be 6.69 Pg C （~0.17 Pg C a^-1） from the 2000s to the 2040s. Climate change induces a rather weak increase in total forest biomass C sequestration （0.52-0.60 Pg C by tile 2040s）. We show that rising CO2 concentrations could further increase tile total forest biomass C sequestration by 1.68-3.12 Pg C in the 2040s across all three scenarios. Overall, the total forest biomass in China would increase by 8.89-10.37 Pg C by the end of 2040s. Our findings highlight the benefits of Chinese afforestation programs, continued climate change and increasing CO2. concentration in sustaining the forest biomass C sink in the near future, and could therefore be useful for designing more realistic climate change mitigation policies such as continuous forestation programs and careful choice of tree species.

关键词： Forest biomass Carbon sequestration Forest age Climate change Rising C02 concentration

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打印微结构对表面电荷积聚特性的影响

高电压技术 2024年第5期50卷 2237-2246页

作者：姚亦桐杨洋牛广乾钱志源刘承山穆海宝西安交通大学电工材料电气绝缘全国重点实验室西安710049 上海宇航系统工程研究所上海201109

航天器等真空设备面临着高电压、小型化的发展需求,但其中的固体-真空绝缘界面容易发生真空沿面闪络。为了提升真空绝缘的沿面耐电性能,通过3D打印技术在绝缘介质表面构建了微刻槽和打印金属两种微结构,并通过电荷积聚实验研究发现了打... 详细信息

航天器等真空设备面临着高电压、小型化的发展需求,但其中的固体-真空绝缘界面容易发生真空沿面闪络。为了提升真空绝缘的沿面耐电性能,通过3D打印技术在绝缘介质表面构建了微刻槽和打印金属两种微结构,并通过电荷积聚实验研究发现了打印微结构能有效抑制表面电荷积聚过程;同时,改变微刻槽数量以及金属的宽度和数量,进一步通过实验对比研究了参数不同时的情况,发现增加微结构的数量和宽度均有利于提升其对电荷积聚的抑制效果;最后,构建真空沿面闪络粒子仿真模型,通过研究电子运动和二次电子崩的发展,并结合实验结果发现微结构能够散射电子,从而产生抑制电荷积聚、提升沿面耐电强度的效果。

关键词：真空沿面闪络 3D打印打印微结构电荷积聚二次电子崩耐电强度

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县级医院高质量发展评价系统建设实践与探索

中国卫生产业 2024年第9期21卷 44-47,52页

作者：顾华姚宜彤杨忠慧李美芳太仓市第一人民医院质量管理处江苏太仓215400 太仓市第一人民医院党政办公室江苏太仓215400 太仓市第一人民医院院长办公室江苏太仓215400

本文主要针对县级医院构建高质量发展评价体系,集成院内病历系统、医疗质量管理系统、运营系统、人力资源系统、科教管理系统、满意度调查等多个业务系统数据结果,搭建县级医院高质量发展评价系统,定量数据收集、汇总和质控,实现结果的... 详细信息

本文主要针对县级医院构建高质量发展评价体系,集成院内病历系统、医疗质量管理系统、运营系统、人力资源系统、科教管理系统、满意度调查等多个业务系统数据结果,搭建县级医院高质量发展评价系统,定量数据收集、汇总和质控,实现结果的可视化、可比性,对提升科室能力、可持续发展、科室运营、满意度评价等指标进行实时数据展示、预警,按月、季度、年进行评分、院内排名,实现院、科两级高质量发展评价体系,全面评价各科室发展情况,掌握其服务能力水平,更好地协助科室进行自身管理、明确发展优势和短板,通过院内专科排名,促进良性竞争,为各科室发展提出可行性建议,进一步推动医院全面实现高质量发展。

关键词：县级医院高质量发展评价体系

Stacked arrangement of substrate integrated waveguide cavity-backed semicircle patches for wideband circular polarization with filtering effect

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Frontiers of Information Technology & Electronic Engineering 2023年第5期24卷 759-766页

作者： yitong yao Gang DONG Zhangming ZHU Yintang YANG School of Microelectronics Xidian UniversityXi’an 710071China

We present a novel broadband circularly polarized(CP)antenna with filtering effect for X-and Kuband satellite wireless *** structure comprises a driven layer(also a filtering layer)and a stacked layer(also a CP layer).The bandpass filtering response consists of two radiation nulls,which is the combined effect of a substrate integrated waveguide(SIW)cavity-backed aperture and embedded driven patch.

关键词： waveguide polarization antenna

Memristive oscillator to memristive map,energy characteristic

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Science China(Technological Sciences) 2024年第5期67卷 1567-1578页

作者： GUO yitong MA Jun ZHANG XiaoFeng HU XiKui College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou730050China Department of Physics Lanzhou University of TechnologyLanzhou730050China School of Science Chongqing University of Posts and TelecommunicationsChongqing400065China

Most of nonlinear oscillators composed of capacitive and inductive variables can obtain the Hamilton energy by using the Helmholtz theorem when the models are rewritten in equivalent vector *** energy functions for biophysical neurons can be obtained by applying scale transformation on the physical field energy in their equivalent neural *** dynamical systems often have exact energy functions,while some mathematical models just suggest generic Lyapunov functions,and the energy function is effective to predict mode *** this paper,a memristive oscillator is approached by two kinds of memristor-based nonlinear circuits,and the energy functions are defined to predict the dependence of oscillatory modes on energy *** absence of capacitive variable for capacitor,the physical time t and charge q are converted into dimensionless variables by using combination of resistance and inductance(L,R),e.g.,τ=t×R/*** energy function for each memristive map is proposed by applying the similar weights as energy function for the memristive *** example,energy function for the map is obtained by replacing the variables and parameters of the memristive oscillator with corresponding variables and parameters for the memristive *** memristive map prefers to keep lower average energy than the memristive oscillator,and chaos is generated in a discrete system with two *** scheme is helpful for energy definition in maps,and it provides possible guidance for verifying the reliability of maps by considering the energy characteristic.

关键词： Hamilton energy memristor Helmholtz theorem scale transformation memristive circuit

Gender and Race Differences in Mental Health and Well-Being Among Older Americans During the COVID-19 Pandemic

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International Journal of Disaster Risk Science 2024年第2期15卷 239-250页

作者： Dongjuan Xu Nasreen Lalani yitong Wang School of Nursing Purdue UniversityWest LafayetteIN 47907USA Center on Aging and the Life Course Purdue UniversityWest LafayetteIN 47907USA

The objectives of this study were to investigate(1) gender and race differences in mental health and psychological wellbeing among older adults during the COVID-19 pandemic and(2) whether there were significant interaction effects between gender and race. This study used the National Health and Aging Trends Study(NHATS) and COVID-19 public use data files. It focused on mental health and psychological well-being, including loneliness, no time to yourself, poor sleep quality, anxiety, depression, and post-traumatic stress disorder(PTSD). The sample consisted of 2465 older adults, and multivariate logistic and linear regression models were adopted for the analysis. The results show that approximately two out of five older people(43%) experienced poor sleep, followed by loneliness(35%), anxiety(30%), depression(23%), and no time to themselves(11%). The average PTSD score was 11. Mental health and psychological well-being varied by gender and race. There were significant interaction effects on anxiety and depression between females and Black older adults. Black females reported lower levels of anxiety and depressive symptoms than Black males, although the differences were not statistically significant. Black older adults were more likely to experience PTSD but less likely to feel lonely and have poorer sleep than their White counterparts. Female older adults reported poorer mental health and psychological well-being than males, except for Black females. Black females had the lowest levels of anxiety, depression, loneliness, and highest quality of sleep among all females of different ethnic and racial origins.

关键词： COVID-19 Gender Mental health Older adults Psychological well-being Race and ethnicity United States

Modular Soft Robotic Crawlers Based on Fluidic Prestressed Composite Actuators

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Journal of Bionic Engineering 2024年第2期21卷 694-706页

作者： Zefeng Xu Linkai Hu Longya Xiao Hongjie Jiang yitong Zhou Shien-Ming Wu School of Intelligent Engineering South China University of TechnologyGuangzhou511442China School of Mechanical and Electrical Engineering Guangzhou UniversityGuangzhou510006China

Soft robotic crawlers have limited payload capacity and crawling *** study proposes a high-performance inchworm-like modular robotic crawler based on fluidic prestressed composite(FPC)*** FPC actuator is precurved and a pneumatic source is used to flatten it,requiring no energy cost to maintain the equilibrium curved *** and depressurizing the actuators generate alternating stretching and bending motions of the actuators,achieving the crawling motion of the robotic ***-modal locomotion(crawling,turning,and pipe climbing)is achieved by modular reconfiguration and gait *** analytical kinematic model is proposed to characterize the quasi-static curvature and step size of a single-module *** configurations of robotic crawlers are fabricated to demonstrate the crawling ability of the proposed design.A set of systematic experiments are set up and conducted to understand how crawler responses vary as a function of FPC prestrains,input pressures,and actuation *** per the experiments,the maximum carrying load ratio(carrying load divided by robot weight)is found to be 22.32,and the highest crawling velocity is 3.02 body length(BL)per second(392 mm/s).Multi-modal capabilities are demonstrated by reconfiguring three soft crawlers,including a matrix crawler robot crawling in amphibious environments,and an inching crawler turning at an angular velocity of 2/s,as well as earthworm-like crawling robots climbing a 20 inclination slope and pipe.

关键词： Soft robot Soft crawler Fluidic prestressed composite Kinematic model Enhanced loading Multi-modal capability