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Valorization of Camellia oleifera oil processing byproducts to value-added chemicals and biobased materials: A critical review 被引量:1
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作者 Xudong Liu Yiying Wu +11 位作者 Yang Gao Zhicheng Jiang Zicheng Zhao Wenquan Zeng Mingyu Xie Sisi Liu Rukuan Liu Yan Chao Suli Nie Aihua Zhang Changzhu Li Zhihong Xiao 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期28-53,共26页
The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,bi... The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,birch,etc.),Camellia wastes contain diverse bioactive substances in addition to the abundant lignocellulosic components,and thus,the biorefinery utilization of C.oleifera processing byproducts involves complicated processing technologies.This reviewfirst summarizes various technologies for extracting and converting the main components in C.oleifera oil processing byproducts into value-added chemicals and biobased materials,as well as their potential applications.Microwave,ultrasound,and Soxhlet extractions are compared for the extraction of functional bioactive components(tannin,flavonoid,saponin,etc.),while solvothermal conversion and pyrolysis are discussed for the conversion of lignocellulosic components into value-added chemicals.The application areas of these chemicals according to their properties are introduced in detail,including utilizing antioxidant and anti-in-flammatory properties of the bioactive substances for the specific application,as well as drop-in chemicals for the substitution of unrenewable fossil fuel-derived products.In addition to chemical production,biochar fabricated from COS and its applications in thefields of adsorption,supercapacitor,soil remediation and wood composites are comprehensively reviewed and discussed.Finally,based on the compositions and structural characteristics of C.oleifera byproducts,the development of full-component valorization strategies and the expansion of the appli-cationfields are proposed. 展开更多
关键词 Camellia oleifera shell Camellia oleifera cake value-added chemicals Bioactive components Biobased materials
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Upcycling plastic wastes into value-added products via electrocatalysis and photoelectrocatalysis
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作者 Sungsoon Kim Dongjae Kong +1 位作者 Xiaolin Zheng Jong Hyeok Park 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期522-541,共20页
Plastic,renowned for its versatility,durability,and cost-effectiveness,is indispensable in modern society.Nevertheless,the annual production of nearly 400 million tons of plastic,coupled with a recycling rate of only ... Plastic,renowned for its versatility,durability,and cost-effectiveness,is indispensable in modern society.Nevertheless,the annual production of nearly 400 million tons of plastic,coupled with a recycling rate of only 9%,has led to a monumental environmental crisis.Plastic recycling has emerged as a vital response to this crisis,offering sustainable solutions to mitigate its environmental impact.Among these recycling efforts,plastic upcycling has garnered attention,which elevates discarded plastics into higher-value products.Here,electrocatalytic and photoelectrocatalytic treatments stand at the forefront of advanced plastic upcycling.Electrocatalytic or photoelectrocatalytic treatments involve chemical reactions that facilitate electron transfer through the electrode/electrolyte interface,driven by electrical or solar energy,respectively.These methods enable precise control of chemical reactions,harnessing potential,current density,or light to yield valuable chemical products.This review explores recent progress in plastic upcycling through electrocatalytic and photoelectrocatalytic pathways,offering promising solutions to the plastic waste crisis and advancing sustainability in the plastics industry. 展开更多
关键词 Plastic upcycling Electrocatalytic reaction Photoelectrocatalytic reaction value-added product
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ICU患者置入Power PICC导管特殊异位原因分析
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作者 莫春玲 屈盈莹 李宝琪 《岭南急诊医学杂志》 2024年第1期58-60,共3页
目的:探讨ICU患者置入Power PICC导管后头端反折向上至同侧和对侧锁骨下静脉、头臂静脉等特殊异位的相关因素。方法:回顾性分析2021年9月至2022年9月某三甲医院ICU 520例PICC置管患者,通过胸部X线确定PICC导管头端反折向上至对侧和同侧... 目的:探讨ICU患者置入Power PICC导管后头端反折向上至同侧和对侧锁骨下静脉、头臂静脉等特殊异位的相关因素。方法:回顾性分析2021年9月至2022年9月某三甲医院ICU 520例PICC置管患者,通过胸部X线确定PICC导管头端反折向上至对侧和同侧锁骨下静脉、头臂静脉的患者,分析其特殊异位发生因素。结果:胸部X线结果显示25例患者PICC管头端反折向上异位至对侧和同侧锁骨下静脉、头臂静脉或颈内静脉,异位发生率4.8%,不同静脉置管反折异位发生率相比差异无统计学意义,P>0.05。结论:ICU患者PICC置入发生导管头端反折向上至同侧和对侧锁骨下静脉、头臂静脉等特殊异位的发生因素较多,包括同时留置CVC或血透管、正在滴注或泵入多种药物、PICC管头端异位的隐匿性、导管材质、自身疾病及机械通气等危险因素。 展开更多
关键词 ICU患者 power PICC 异位 原因分析
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Power-V诱导的钻柱黏滑振动特征分析
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作者 王文昌 段浩宇 +2 位作者 李宁 王孝亮 狄勤丰 《上海大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期299-307,共9页
黏滑是石油钻井过程中影响钻井效率和井下钻柱安全的一种振动形式.垂直钻井系统Power-V在提供有效控斜力的同时,还会诱导钻柱黏滑振动.通过研究垂直钻井系统Power-V与井壁的接触作用及钻头与地层的相互作用模型,基于钻柱动力学有限元方... 黏滑是石油钻井过程中影响钻井效率和井下钻柱安全的一种振动形式.垂直钻井系统Power-V在提供有效控斜力的同时,还会诱导钻柱黏滑振动.通过研究垂直钻井系统Power-V与井壁的接触作用及钻头与地层的相互作用模型,基于钻柱动力学有限元方法,深入分析Power-V的作用机理,研究其对扭转振动的影响,指出Power-V和井壁间的相互作用会导致钻柱与井壁的摩阻显著增加,进而引起摩阻扭矩的增大,诱导井下黏滑振动.实测振动数据证实,Power-V与井壁间的相互作用是引起钻柱黏滑振动的关键因素.这对于揭示黏滑振动的成因和更好地发挥Power-V的作用具有重要意义. 展开更多
关键词 黏滑振动 钻柱动力学 振动信号测量 power-V
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基于调和概率语言术语集的Power平均算子
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作者 辛树琦 王兴 郑小建 《福建师范大学学报(自然科学版)》 CAS 北大核心 2024年第2期1-13,共13页
实践发现现存概率语言Power平均算子在应用中存在概率信息丢失、计算过于繁琐等问题,针对这些问题,提出一种基于调和概率语言术语集的Power平均算子。结合新的基本运算法则与新的支撑度,给出新的概率语言Power平均算子、概率语言Power... 实践发现现存概率语言Power平均算子在应用中存在概率信息丢失、计算过于繁琐等问题,针对这些问题,提出一种基于调和概率语言术语集的Power平均算子。结合新的基本运算法则与新的支撑度,给出新的概率语言Power平均算子、概率语言Power几何平均算子、概率语言Power加权平均算子、概率语言Power加权几何平均算子,同时论证分析了这几类新型算子的性质。最后通过实验数据,将提出的算子与现存算子进行对比分析,验证了所提算子的有效性与可行性。 展开更多
关键词 概率语言术语集 概率语言power平均算子 决策
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Power BI在我院药品数据可视化中的应用
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作者 宋树杰 许桂媛 +2 位作者 马先杰 李祥鹏 刘建芳 《海峡药学》 2024年第8期121-127,共7页
目的加强医院药品精细化管理,提升药师对药品的数据分析能力,实现数据分析自动化及查询功能,为集采药品、麻精药品的动态监管提供数据支撑。方法使用数据可视化工具Power BI搭建服务,制作报表,能够查询药品使用情况和对比情况,实现各科... 目的加强医院药品精细化管理,提升药师对药品的数据分析能力,实现数据分析自动化及查询功能,为集采药品、麻精药品的动态监管提供数据支撑。方法使用数据可视化工具Power BI搭建服务,制作报表,能够查询药品使用情况和对比情况,实现各科室药品使用情况的可视化管理。结果通过该软件,药师可以精确查询任意时间维度下药品的使用数量、金额等情况,实现数据分析自动化。结论借助数据管理工具能够帮助药师提升数据分析能力和工作效率,有助于加强医院药品的精细化管控。 展开更多
关键词 power BI 药品集采 数据分析 药师
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Carbon emission reduction:Contribution of photovoltaic power and practice in China 被引量:1
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作者 Liang Wang Li-qiong Jia +2 位作者 Geng Xie Xi-jie Chen Yang Liu 《China Geology》 CAS CSCD 2024年第2期371-376,共6页
As a clean and renewable form of energy,photovoltaic(PV)power generation converts solar energy into electrical energy,reducing the consumption of fossil fuels and significantly lowering greenhouse gas emissions.Amidst... As a clean and renewable form of energy,photovoltaic(PV)power generation converts solar energy into electrical energy,reducing the consumption of fossil fuels and significantly lowering greenhouse gas emissions.Amidst the global transition towards cleaner forms of energy,countries all around the world are vigorously developing PV technology. 展开更多
关键词 CONVERT power EMISSIONS
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Traction power systems for electrified railways:evolution,state of the art,and future trends 被引量:1
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作者 Haitao Hu Yunjiang Liu +4 位作者 Yong Li Zhengyou He Shibin Gao Xiaojuan Zhu Haidong Tao 《Railway Engineering Science》 EI 2024年第1期1-19,共19页
Traction power systems(TPSs)play a vital role in the operation of electrified railways.The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified ... Traction power systems(TPSs)play a vital role in the operation of electrified railways.The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified railways toward high-efficiency and resilience but also an inevitable requirement to achieve carbon neutrality target.On the basis of sorting out the power supply structures of conventional AC and DC modes,this paper first reviews the characteristics of the existing TPSs,such as weak power supply flexibility and low-energy efficiency.Furthermore,the power supply structures of various TPSs for future electrified railways are described in detail,which satisfy longer distance,low-carbon,high-efficiency,high-reliability and high-quality power supply requirements.Meanwhile,the application prospects of different traction modes are discussed from both technical and economic aspects.Eventually,this paper introduces the research progress of mixed-system electrified railways and traction power supply technologies without catenary system,speculates on the future development trends and challenges of TPSs and predicts that TPSs will be based on the continuous power supply mode,employing power electronic equipment and intelligent information technology to construct a railway comprehensive energy system with renewable energy. 展开更多
关键词 Railway traction power system Future electrified railway Flexible continuous power supply Renewable energy Integrated energy system
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基于Power BI的DRGs数据分析方法 被引量:1
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作者 李昕昊 曾少婷 +3 位作者 叶丽娴 陈沛琳 陈润斐 潘宗林 《中国数字医学》 2024年第1期83-88,共6页
目的:探讨利用Power BI工具对DRGs数据进行有效分析,揭示潜在的数据特征和规律。方法:运用Power BI工具对2017年―2021年DRGs数据进行数据连接、数据清洗和处理等操作,提取和计算相关DRGs评价指标,最后通过可视化展示的方式对DRGs数据... 目的:探讨利用Power BI工具对DRGs数据进行有效分析,揭示潜在的数据特征和规律。方法:运用Power BI工具对2017年―2021年DRGs数据进行数据连接、数据清洗和处理等操作,提取和计算相关DRGs评价指标,最后通过可视化展示的方式对DRGs数据进行分析和呈现,从不同维度和角度深入研究DRGs数据特征和规律。结果:通过对2017年―2021年DRGs数据处理和可视化展示,能直观了解出院患者疾病构成、医疗资源利用、临床质量评估和医疗成本效益等总体情况,为提高医疗服务质量和资源利用效率等提供可行的解决方案。结论:基于Power BI的DRGs数据分析方法能够有效地帮助医院进行医疗费用控制和资源配置,并提高医疗服务的质量和效率。此方法为优化DRGs数据管理和医疗资源配置提供了重要的参考和借鉴价值。 展开更多
关键词 DRGS 数据可视化 智能报表 power BI
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Reactive ball-milling synthesis of Co-Fe bimetallic catalyst for efficient hydrogenation of carbon dioxide to value-added hydrocarbons
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作者 Haipeng Chen Chenwei Wang +5 位作者 Mengyang Zheng Chenlei Liu Wenqiang Li Qingfeng Yang Shixue Zhou Xun Feng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第9期210-218,共9页
Catalytic hydrogenation of CO_(2) using renewable hydrogen not only reduces greenhouse gas emissions,but also provides industrial chemicals.Herein,a Co-Fe bimetallic catalyst was developed by a facile reactive ball-mi... Catalytic hydrogenation of CO_(2) using renewable hydrogen not only reduces greenhouse gas emissions,but also provides industrial chemicals.Herein,a Co-Fe bimetallic catalyst was developed by a facile reactive ball-milling method for highly active and selective hydrogenation of CO_(2) to value-added hydrocarbons.When reacted at 320℃,1.0 MPa and 9600 mL h^(-1) g_(cat)^(-1),the selectivity to light olefin(C_(2)^(=)-C_(4)^(=)) and C_(5)+ species achieves 57.3% and 22.3%,respectively,at a CO_(2) co nversion of 31.4%,which is superior to previous Fe-based catalysts.The CO_(2) activation can be promoted by the CoFe phase formed by reactive ball milling of the Fe-Co_(3)O_(4) mixture,and the in-situ Co_(2)C and Fe_(5)C_(2) formed during hydrogenation are beneficial for the C-C coupling reaction.The initial C-C coupling is related to the combination of CO species with the surface carbon of Fe/Co carbides,and the sustained C-C coupling is maintained by self-recovery of defective carbides.This new strategy contributes to the development of efficient catalysts for the hydrogenation of CO_(2) to value-added hydrocarbons. 展开更多
关键词 Reactive ball milling Co-Fe bimetallic catalyst Carbon dioxide value-added hydrocarbon C–C coupling reaction
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Power BI在移民信息管理中的应用研究
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作者 孙圆亮 罗勇 +2 位作者 唐志坚 李俊峰 丁紫玉 《水利水电快报》 2024年第8期124-129,共6页
信息技术的应用是提高水利工程移民信息化水平的重要手段,针对现有移民信息管理系统灵活性和通用性低的问题,分析了微软Power BI系列软件实现移民信息管理的可行性。以山东省老岚水库移民项目为例,使用该软件依次快捷完成移民信息的收... 信息技术的应用是提高水利工程移民信息化水平的重要手段,针对现有移民信息管理系统灵活性和通用性低的问题,分析了微软Power BI系列软件实现移民信息管理的可行性。以山东省老岚水库移民项目为例,使用该软件依次快捷完成移民信息的收集、整理和分析工作,并设计出交互式可视化界面,从多个维度展示和查询各类移民信息以及实现移民数据的多端实时共享。研究表明:运用Power BI系列软件虽然在结合地理信息方面仍存在不足,但能够以较低的使用难度和投入成本完成移民信息管理及可视化工作,提高工作效率。验证了其在移民信息管理方面的实用性和适用性,具备一定的推广价值。 展开更多
关键词 移民信息管理 信息化 power BI 水利工程
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Field test of high-power microwave-assisted mechanical excavation for deep hard iron ore 被引量:1
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作者 Feng Lin Xia-Ting Feng +5 位作者 Shiping Li Xiao Hai Jiuyu Zhang Xiangxin Su Tianyang Tong Jianchun Song 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期1922-1935,共14页
Microwave-assisted mechanical excavation has great application prospects in mines and tunnels,but there are few field experiments on microwave-assisted rock breaking.This paper takes the Sishanling iron mine as the re... Microwave-assisted mechanical excavation has great application prospects in mines and tunnels,but there are few field experiments on microwave-assisted rock breaking.This paper takes the Sishanling iron mine as the research object and adopts the self-developed high-power microwave-induced fracturing test system for hard rock to conduct field experiments of microwave-induced fracturing of iron ore.The heating and reflection evolution characteristics of ore under different microwave parameters(antenna type,power,and working distance)were studied,and the optimal microwave parameters were obtained.Subsequently,the ore was irradiated with the optimal microwave parameters,and the cracking effect of the ore under the action of the high-power open microwave was analyzed.The results show that the reflection coefficient(standing wave ratio)can be rapidly(<5 s)and automatically adjusted below the preset threshold value(1.6)as microwave irradiation is performed.When using a right-angle horn antenna with a working distance of 5 cm,the effect of automatic reflection adjustment reaches the best among other antenna types and working distances.When the working distance is the same,the average temperature of the irradiation surface and the area of the high-temperature area under the action of the two antennas(right-angled and equal-angled horn antenna)are basically the same and decrease with the increase of working distance.The optimal microwave parameters are:a right-angle horn antenna with a working distance of 5 cm.Subsequently,in further experiments,the optimal parameters were used to irradiate for 20 s and 40 s at a microwave power of 60 kW,respectively.The surface damage extended 38 cm×30 cm and 53 cm×30 cm,respectively,and the damage extended to a depth of about 50 cm.The drilling speed was increased by 56.2%and 66.5%,respectively,compared to the case when microwaves were not used. 展开更多
关键词 Microwave parameters High power Field experiment Mechanical mining
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A Novel Multiple DBC-staked units Package to Parallel More Chips for SiC Power Module 被引量:1
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作者 Xiaoshuang Hui Puqi Ning +4 位作者 Tao Fan Yuhui Kang Kai Wang Yunhui Mei Guangyin Lei 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期72-79,共8页
Silicon carbide(SiC) power modules play an essential role in the electric vehicle drive system. To improve their performance, reduce their size, and increase production efficiency, this paper proposes a multiple stake... Silicon carbide(SiC) power modules play an essential role in the electric vehicle drive system. To improve their performance, reduce their size, and increase production efficiency, this paper proposes a multiple staked direct bonded copper(DBC) unit based power module packaging method to parallel more chips. This method utilizes mutual inductance cancellation effect to reduce parasitic inductance. Because the conduction area in the new package is doubled, the overall area of power module can be reduced. Entire power module is divided into smaller units to enhance manufacture yield, and improve design freedom. This paper provides a detailed design, analysis and fabrication procedure for the proposed package structure. Additionally, this paper offers several feasible solutions for the connection between power terminals and DBC untis. With the structure, 18dies were paralleled for each phase-leg in a econodual size power module. Both simulation and double pulse test results demonstrate that, compared to conventional layouts, the proposed package method has 74.8% smaller parasitic inductance and 34.9% lower footprint. 展开更多
关键词 Silicon carbide Electric vehicle power modules PACKAGE
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Demonstration of a small‐scale power generator using supercritical CO_(2) 被引量:1
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作者 Ligeng Li Hua Tian +7 位作者 Xin Lin Xianyu Zeng Yurong Wang Weilin Zhuge Lingfeng Shi Xuan Wang Xingyu Liang Gequn Shu 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期269-290,共22页
The supercritical CO_(2)(sCO_(2))power cycle could improve efficiencies for a wide range of thermal power plants.The sCO_(2)turbine generator plays an important role in the sCO_(2)power cycle by directly converting th... The supercritical CO_(2)(sCO_(2))power cycle could improve efficiencies for a wide range of thermal power plants.The sCO_(2)turbine generator plays an important role in the sCO_(2)power cycle by directly converting thermal energy into mechanical work and electric power.The operation of the generator encounters challenges,including high temperature,high pressure,high rotational speed,and other engineering problems,such as leakage.Experimental studies of sCO_(2)turbines are insufficient because of the significant difficulties in turbine manufacturing and system construction.Unlike most experimental investigations that primarily focus on 100 kW‐or MW‐scale power generation systems,we consider,for the first time,a small‐scale power generator using sCO_(2).A partial admission axial turbine was designed and manufactured with a rated rotational speed of 40,000 rpm,and a CO_(2)transcritical power cycle test loop was constructed to validate the performance of our manufactured generator.A resistant gas was proposed in the constructed turbine expander to solve the leakage issue.Both dynamic and steady performances were investigated.The results indicated that a peak electric power of 11.55 kW was achieved at 29,369 rpm.The maximum total efficiency of the turbo‐generator was 58.98%,which was affected by both the turbine rotational speed and pressure ratio,according to the proposed performance map. 展开更多
关键词 GENERATOR performance map power generation supercritical CO_(2) TURBINE
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基于Power BI的三级公立医院绩效考核病案首页指标数据分析与可视化展示 被引量:2
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作者 梁碧玉 张宇琼 +1 位作者 陈俊樱 何伟明 《中国医院统计》 2024年第1期72-76,共5页
目的在三级公立医院绩效考核背景下,探寻一种基于Power BI的数据统计分析及可视化展示方法,提高医院统计人员数据统计及分析效率。通过可视化助力日常指标监测,推动医疗管理的效率和质量提升,辅助管理决策。方法提取某三甲医院2022年1月... 目的在三级公立医院绩效考核背景下,探寻一种基于Power BI的数据统计分析及可视化展示方法,提高医院统计人员数据统计及分析效率。通过可视化助力日常指标监测,推动医疗管理的效率和质量提升,辅助管理决策。方法提取某三甲医院2022年1月1日至2023年6月30日的病案首页数据,根据三级公立医院绩效考核病案首页指标数据统计口径,建立基于Power BI的三级公立医院绩效考核病案首页指标数据查询系统,进行数据分析及可视化展示。结果基于Power BI的三级公立医院绩效考核病案首页指标数据查询系统可快速查询多维度、多场景的指标数据,具有实用性及易操作性。结论Power BI可作为医院统计工作人员进行数据分析及可视化展示的工具,值得推广使用。医院统计工作人员可结合本研究将Power BI运用于实际工作中,提高工作效率,助力日常统计工作。 展开更多
关键词 power BI 三级公立医院绩效考核 病案首页 数据分析 可视化
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A frequency servo SoC with output power stabilization loop technology for miniaturized atomic clocks 被引量:1
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作者 Hongyang Zhang Xinlin Geng +3 位作者 Zonglin Ye Kailei Wang Qian Xie Zheng Wang 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期13-22,共10页
A frequency servo system-on-chip(FS-SoC)featuring output power stabilization technology is introduced in this study for high-precision and miniaturized cesium(Cs)atomic clocks.The proposed power stabilization loop(PSL... A frequency servo system-on-chip(FS-SoC)featuring output power stabilization technology is introduced in this study for high-precision and miniaturized cesium(Cs)atomic clocks.The proposed power stabilization loop(PSL)technique,incorporating an off-chip power detector(PD),ensures that the output power of the FS-SoC remains stable,mitigating the impact of power fluctuations on the atomic clock's stability.Additionally,a one-pulse-per-second(1PPS)is employed to syn-chronize the clock with GPS.Fabricated using 65 nm CMOS technology,the measured phase noise of the FS-SoC stands at-69.5 dBc/Hz@100 Hz offset and-83.9 dBc/Hz@1 kHz offset,accompanied by a power dissipation of 19.7 mW.The Cs atomic clock employing the proposed FS-SoC and PSL obtains an Allan deviation of 1.7×10^(-11) with 1-s averaging time. 展开更多
关键词 CMOS technology atomic clock phase-locked loop output power stabilization 1PPS
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Effect of bubble morphology and behavior on power consumption in non-Newtonian fluids’aeration process 被引量:1
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作者 Xiemin Liu Jing Wan +5 位作者 Jinnan Sun Lin Zhang Feng Zhang Zhibing Zhang Xinyao Li Zheng Zhou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期243-254,共12页
Due to a prolonged operation time and low mass transfer efficiency, the primary challenge in the aeration process of non-Newtonian fluids is the high energy consumption, which is closely related to the form and rate o... Due to a prolonged operation time and low mass transfer efficiency, the primary challenge in the aeration process of non-Newtonian fluids is the high energy consumption, which is closely related to the form and rate of impeller, ventilation, rheological properties and bubble morphology in the reactor. In this perspective, through optimal computational fluid dynamics models and experiments, the relationship between power consumption, volumetric mass transfer rate(kLa) and initial bubble size(d0) was constructed to establish an efficient operation mode for the aeration process of non-Newtonian fluids. It was found that reducing the d0could significantly increase the oxygen mass transfer rate, resulting in an obvious decrease in the ventilation volume and impeller speed. When d0was regulated within 2-5 mm,an optimal kLa could be achieved, and 21% of power consumption could be saved, compared to the case of bubbles with a diameter of 10 mm. 展开更多
关键词 Non-Newtonian fluids aeration process power consumption Volumetric mass transfer rate Bubble size
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11.2 W/mm power density AlGaN/GaN high electron-mobility transistors on a GaN substrate 被引量:1
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作者 Yansheng Hu Yuangang Wang +11 位作者 Wei Wang Yuanjie Lv Hongyu Guo Zhirong Zhang Hao Yu Xubo Song Xingye zhou Tingting Han Shaobo Dun Hongyu Liu Aimin Bu Zhihong Feng 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期38-41,共4页
In this letter,high power density AlGaN/GaN high electron-mobility transistors(HEMTs)on a freestanding GaN substrate are reported.An asymmetricΓ-shaped 500-nm gate with a field plate of 650 nm is introduced to improv... In this letter,high power density AlGaN/GaN high electron-mobility transistors(HEMTs)on a freestanding GaN substrate are reported.An asymmetricΓ-shaped 500-nm gate with a field plate of 650 nm is introduced to improve microwave power performance.The breakdown voltage(BV)is increased to more than 200 V for the fabricated device with gate-to-source and gate-to-drain distances of 1.08 and 2.92μm.A record continuous-wave power density of 11.2 W/mm@10 GHz is realized with a drain bias of 70 V.The maximum oscillation frequency(f_(max))and unity current gain cut-off frequency(f_(t))of the AlGaN/GaN HEMTs exceed 30 and 20 GHz,respectively.The results demonstrate the potential of AlGaN/GaN HEMTs on freestanding GaN substrates for microwave power applications. 展开更多
关键词 freestanding GaN substrates AlGaN/GaN HEMTs continuous-wave power density breakdown voltage Γ-shaped gate
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Multi-objective optimization and evaluation of supercritical CO_(2) Brayton cycle for nuclear power generation 被引量:1
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作者 Guo-Peng Yu Yong-Feng Cheng +1 位作者 Na Zhang Ping-Jian Ming 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期183-209,共27页
The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayto... The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear energy.Parametric analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic indexes.Results show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic performance.Among the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOE)of 0.012$/(kWh).The nuclear Brayton cycle system’s overall performance has been improved due to optimization.The performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,respectively.The performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited funds.For the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully. 展开更多
关键词 Supercritical CO_(2)Brayton cycle Nuclear power generation Thermo-economic analysis Multi-objective optimization Decision-making methods
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Waste Cotton-Derived Fiber-Based Thermoelectric Aerogel for Wearable and Self-Powered Temperature-Compression Strain Dual-Parameter Sensing
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作者 Xinyang He Mingyuan Liu +7 位作者 Jiaxin Cai Zhen Li Zhilin Teng Yunna Hao Yifan Cui Jianyong Yu Liming Wang Xiaohong Qin 《Engineering》 SCIE EI CAS CSCD 2024年第8期235-243,共9页
The rapid development of the global economy and population growth are accompanied by the production of numerous waste textiles.This leads to a waste of limited resources and serious environmental pollution problems ca... The rapid development of the global economy and population growth are accompanied by the production of numerous waste textiles.This leads to a waste of limited resources and serious environmental pollution problems caused by improper disposal.The rational recycling of wasted textiles and their transformation into high-value-added emerging products,such as smart wearable devices,is fascinating.Here,we propose a novel roadmap for turning waste cotton fabrics into three-dimensional elastic fiber-based thermoelectric aerogels by a one-step lyophilization process with decoupled self-powered temperature-compression strain dual-parameter sensing properties.The thermoelectric aerogel exhibits a fast compression response time of 0.2 s,a relatively high Seebeck coefficient of 43μV·K^(-1),and an ultralow thermal conductivity of less than 0.04 W·m^(-1)·K^(-1).The cross-linking of trimethoxy(methyl)silane(MTMS)and cellulose endowed the aerogel with excellent elasticity,allowing it to be used as a compressive strain sensor for guessing games and facial expression recognition.In addition,based on the thermoelectric effect,the aerogel can perform temperature detection and differentiation in self-powered mode with the output thermal voltage as the stimulus signal.Furthermore,the wearable system,prepared by connecting the aerogel-prepared array device with a wireless transmission module,allows for temperature alerts in a mobile phone application without signal interference due to the compressive strains generated during gripping.Hence,our strategy is significant for reducing global environmental pollution and provides a revelatory path for transforming waste textiles into high-value-added smart wearable devices. 展开更多
关键词 Waste textiles High value-added recycling THERMOELECTRICS ELASTICITY Decoupled sensing
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