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高功率密度无刷直流电动机设计研究

现代机械 2019年第3期 35-38页

作者：谭耳赵飞覃万健贵州航天林泉电机有限公司贵州贵阳550081 国家精密微特电机工程技术研究中心贵州贵阳550081

本文提出了一种高功率密度无刷直流电动机,介绍了高功率密度无刷直流电动机的应用前景,阐述了该电机电磁场和应力场设计的基本要点,并对其进行了电磁场和应力场仿真。仿真结果表明,电机各个工作点满足技术性能要求,整机结构强度和转子... 详细信息

本文提出了一种高功率密度无刷直流电动机,介绍了高功率密度无刷直流电动机的应用前景,阐述了该电机电磁场和应力场设计的基本要点,并对其进行了电磁场和应力场仿真。仿真结果表明,电机各个工作点满足技术性能要求,整机结构强度和转子共振频率设计合理。试验结果验证了该电机设计的正确性。

关键词：高功率密度无刷直流电动机电磁场应力场共振频率

Subpopulations of regulatory T cells are associated with subclinical atherosclerotic plaques,levels of LDL,and cardiorespiratory fitness in the elderly

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Journal of Sport and Health Science 2024年第3期13卷 288-296,I0002页

作者： Tim Böttrich Pascal Bauer Vincent Gröβer Magdalena Huber Hartmann Raifer Torsten Frech Svenja Nolte Theresa Dombrowski Franz Cemic Natascha Sommer Robert Ringseis Klaus Eder Karsten Krüger Christopher Weyh Department of Exercise Physiology and Sports Therapy Institute of Sports ScienceJustus-Liebig-UniversityGiessen 35394Germany Department of Cardiology and Angiology Justus-Liebig-University GiessenGiessen 35392Germany Institute for Systems Immunology Center for Tumor und ImmunologyMarburg 35032Germany TH Mittelhessen Department of Computer ScienceUniversity of Applied Sciences GiessenGiessen 35390Germany Department of Internal Medicine Universities of Giessen and Marburg Lung Center(UGMLC)Member of the German Center for Lung Research(DZL)Giessen 35394Germany Excellence Cluster Cardio-Pulmonary Institute(CPI) Justus-Liebig UniversityGiessen 35394Germany Institute of Animal Nutrition and Nutrition Physiology Justus-Liebig-University GiessenGiessen 35390Germany

Background:Atherosclerosis forms the pathological basis for the development of cardiovascular *** pathological processes initially develop without clinically relevant symptoms,the identification of early markers in the subclinical stage plays an important role for initiating early *** is evidence that regulatory T cells(Tregs)are involved in the development of ***,the present study aimed to identify and investigate associations with Tregs and their subsets in a cohort of healthy elderly individuals with and without subclinical atherosclerotic plaques(SAP).In addition,various lifestyle and risk factors,such as cardiorespiratory fitness,were investigated as associated ***:A cross-sectional study was performed in 79 participants(male:n=50;age=63.6±3.7 years;body mass index=24.9±3.1 kg/m2;mean±SD)who had no previous diagnosis of chronic disease and were not taking *** of the carotids to identify SAP,cardiovascular function measurement for vascular assessment and a cardiorespiratory fitness test to determine peak oxygen uptake were ***,tests were conducted to assess blood lipids and determine glucose *** of Tregs and their subtypes(resting(rTregs)and effector/memory(mTregs))was performed by 8-chanel flow *** were categorized according to atherosclerotic plaque *** and logistic regression models were used to analyze associations between ***:SAP was detected in a total of 29 *** participants with plaque were older(64.8±3.6 years vs.62.9±3.5 years)and had higher peripheral systolic blood pressure(133.8±14.7 mmHg vs.125.8±10.9 mmHg).The participants with SAP were characterized by a lower percentage of rTregs(28.8%±10.7%vs.34.6%±10.7%)and a higher percentage of mTregs(40.3%±14.7%vs.30.0%±11.9%).Multiple logistic regression identified age(odds ratio(OR)=1.20(95%confidence interval(95%CI):1.011.42))and

关键词： Cardiorespiratory fitness Elderly Regulatory T cells Subclinical atherosclerosis

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高分辨率罗兰圆光学系统的色差校正方法研究

光谱学与光谱分析 2024年第7期44卷 2011-2017页

作者：陈吉文陈作儿北方工业大学电气与控制工程学院北京100144

罗兰圆光学系统优点众多,但系统中因平凸透镜的使用,导致各特征波长色散后的成像点在罗兰圆附近产生了一定量的偏移量,使得各波长成像点依次排列在一条曲面上。由于目前新型采集器件线阵CMOS或CCD的使用,而这类传感器的感光面是一个平面... 详细信息

罗兰圆光学系统优点众多,但系统中因平凸透镜的使用,导致各特征波长色散后的成像点在罗兰圆附近产生了一定量的偏移量,使得各波长成像点依次排列在一条曲面上。由于目前新型采集器件线阵CMOS或CCD的使用,而这类传感器的感光面是一个平面,因此导致结果产生较严重的色差。提出了一种使用加权最小二乘法拟合像面的色差校正方法,并计算出系统像面的中心偏移距和偏移倾斜角这两个校正参数,将其引入原本罗兰圆光学系统进行色差校正,从而确定线阵光电传感器像面的最佳位置,实现高分辨率。此外在真空紫外光谱中C、P和S等元素非常重要,可使用本文提出的基于加权最小二乘法的色差校正方法,通过增加这类元素权值占比,实现最优分辨率。最后通过Zemax软件进行光学仿真,完成了罗兰圆光学系统的仿真以及优化。并给出170~410 nm波段点列图的成像宽度仿真以及各元素特征波长在CMOS传感器上所采集到的光谱图,推算出其实际应用中的分辨率,其照度光谱图显示其分辨率均可保持在0.02 nm,接近系统理论最佳分辨率。研究结果表明基于加权最小二乘法拟合像面的方法,可实现罗兰圆光学系统的色差校正,实现高分辨率。

关键词：罗兰圆光学系统平凸透镜色差校正高分辨率加权最小二乘法

无电荷层InGaAs/Si雪崩光电探测器的优化设计

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光学学报 2024年第5期44卷 19-28页

作者：张娟姚儿柯少颖闽南师范大学物理与信息工程学院光场调控及其系统集成应用福建省高校重点实验室福建漳州363000

目前,在近红外波段中普遍采用InGaAs/InP雪崩光电二极管(APD),但这类APD存在增益带宽积小和等效噪声高等问题,而InGaAs/Si APD采用电子、空穴离化系数极低的Si材料作为倍增层,在一定程度解决了上述问题,但其制造过程涉及Si电荷层的离子... 详细信息

目前,在近红外波段中普遍采用InGaAs/InP雪崩光电二极管(APD),但这类APD存在增益带宽积小和等效噪声高等问题,而InGaAs/Si APD采用电子、空穴离化系数极低的Si材料作为倍增层,在一定程度解决了上述问题,但其制造过程涉及Si电荷层的离子注入和高温退火激活,该过程工艺复杂、杂质分布不均匀、成本高。因此,本研究采用刻蚀技术在Si倍增层内制备凹槽环,并在凹槽环内填充不同介质对InGaAs层及Si层内的电场进行调控,构建无电荷层InGaAs/Si APD器件模型。结果表明,在凹槽环内填充空气或SiO2可获得高性能的InGaAs/Si APD。该研究结果可为后续研制工艺简单、性能稳定、低噪声的InGaAs/Si APD提供理论指导。

关键词：探测器雪崩光电二极管增益带宽积电荷层凹槽环

Influence of Lightning Disaster on Cities and Lightning Defense Measures

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Meteorological and Environmental Research 2024年第3期15卷 65-67页

作者： Pei WANG Tao ZHANG Tengge'er WU Xiangjun ZHANG Ulanqab Meteorological Bureau Ulanqab 012000China Huade Meteorological Bureau Ulanqab 013350China Xilinhot Meteorological Bureau Xilinhot 026000China

Under the influence of special terrain and climatic conditions,lightning weather in Ulanqab City is more frequent from June to August,and lightning disaster has become one of the important tasks of disaster prevention and *** this paper,based on the characteristics of lightning weather in Ulanqab City,the impact of lightning disaster on the city was analyzed,and lightning protection measures,such as strengthening supervision of lightning protection safety,establishing a long-term lightning protection mechanism,doing a good job in lightning protection construction and detection in key places,and further improving public awareness of lightning protection,were put forward to reduce and avoid urban lightning disasters as much as possible and ensure urban safety.

关键词： Lightning characteristics Disaster impact City Lightning protection measures

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试论中国大运河世界遗产的系列扩展

东南文化 2024年第2期 15-24页

作者：李尔吾西北大学文化遗产学院陕西西安710119

中国大运河世界遗产符合世界文化遗产中的遗产运河、文化景观、文化线路类型。中国大运河基于工程技术类线形遗产的扩展应完善水工遗存的系列完整性并扩大遗产时空范围;基于文化景观的扩展应将沿线展现人们生产生活的各种景观组成大运... 详细信息

中国大运河世界遗产符合世界文化遗产中的遗产运河、文化景观、文化线路类型。中国大运河基于工程技术类线形遗产的扩展应完善水工遗存的系列完整性并扩大遗产时空范围;基于文化景观的扩展应将沿线展现人们生产生活的各种景观组成大运河文化景观群;基于文化线路的扩展应构建大运河水陆遗产综合体,并强调运河与城镇、城镇与城镇间的动态演化关系。

关键词：中国大运河世界遗产系列扩展遗产运河文化景观文化线路价值特征文化价值

Unlocking the sun’s potential:Vitamin D’s role in battling colorectal cancer

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Journal of Nutritional Oncology 2024年第1期9卷 1-9页

作者： Qing-er Ling Si-Qi Ni Yi Jiao Ling-Xiang Liu Department of Oncology Jiangsu Province HospitalNanjing 210000JiangsuChina

Vitamin D,a fat-soluble hormone precursor primarily derived from sunlight exposure,exerts pleiotropic effects within the body,including anticancer *** has demonstrated an association between vitamin D and colorectal cancer(CRC)from both geoecological and epidemiological perspectives,wherein vitamin D intake and circulating levels have clinical significance for the development of CRC and confer a protective effect against the *** such,a sensible increase in sunlight exposure may be an accessible approach to reducing cancer risk and a low-cost treatment when used in conjunction with vitamin D *** article comprehensively explores the established and emerging mechanisms thought to underlie the impact of vitamin D on *** encompasses recent insights from clinical trials and epidemiological studies,along with recommendations,diverse viewpoints,and future prospects regarding the utilization of vitamin D in the management of CRC.

关键词： Colorectal cancer Vitamin D Calcitriol

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藏药康定乌头质量标准研究

中药材 2014年第6期37卷 977-980页

作者：周礼仕王毓杰杜蕾蕾谭尔泽翁拥忠降拥四郎张艺成都中医药大学民族医药学院四川成都611137

目的：建立康定乌头的质量标准。方法：以滇乌头碱、塔拉萨敏为对照品进行康定乌头的薄层鉴别；采用HPLC法测定康定乌头中滇乌头碱的含量。对康定乌头水分、总灰分、酸不溶性灰分、醇溶性浸出物及显微特征进行检测。结果：康定乌头的显... 详细信息

目的：建立康定乌头的质量标准。方法：以滇乌头碱、塔拉萨敏为对照品进行康定乌头的薄层鉴别；采用HPLC法测定康定乌头中滇乌头碱的含量。对康定乌头水分、总灰分、酸不溶性灰分、醇溶性浸出物及显微特征进行检测。结果：康定乌头的显微特征性强；薄层色谱分离度好，斑点清晰；水分为10．89％～12．07％（平均值11．48％），总灰分为4．81％～5．00％（平均值4．83％），酸不溶性灰分为1．08％-3．27％（平均值1．81％）；浸出物为18．03％～28．27％（平均值20．46％）；滇乌头碱的含量为0．18％～0．35％（平均值0．23％）。结论：所建方法操作简单，准确可靠，可用于评价康定乌头的质量。

关键词：康定乌头质量标准薄层鉴别含量测定滇乌头碱塔拉萨敏

Gentiana macrophylla Pall.:a review of the basic source,traditional use,chemical components,pharmacological activities and quality control

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Traditional Medicine Research 2024年第12期9卷 13-30页

作者： Qi-er Mu Yi-Sa A Yan-Qiu Bai Chu-La Sa College of Mongolian Medicine Inner Mongolian Medical UniversityJinshan Economic and Technological Development ZoneTumote Left BannerHohhot 010110China

Gentiana macrophylla Pall.(***),whose genus and family belong to the Gentianaceae and *** main distribution centers of *** resources were the Loess Plateau and the eastern Qinghai-Tibet Plateau in ***,as a traditional medicine,has a long history and was used in different ethnic *** roots were used in traditional Chinese medicine,which had the effect of anti-inflammatory,anti-rheumatism,antiviral,promote blood circulation,eliminate swelling and pain,while its flowers were used in traditional Mongolian medicine,which had the effect of removing“Xieriwusu”(“Xieriwusu”means rheumatism),antiviral,reducing *** previous studies,it could be found that there were more than forty components isolated and identified from *** main chemical components were iridoids,flavonoids,triterpenoids,steroids,phenylpropanoids,and *** terpenoid components represented by gentiopicroside and Loganic acid were the main components of the root of ***,which had anti-inflammatory,antioxidant,hepatoprotective,analgesic,antibacterial and promote gastrointestinal tract *** flower mainly contains isoorientin and isovitexin as the representative of *** have anti-tumor,liver protection,heart protection,inhibition of acetylcholinesterase and inhibition of *** could be seen from previous studies that the research on *** was mainly focused on the root,and the flower was rarely *** was reported that the experimental data of the anti-inflammatory and anti-tumor effects of *** flowers show that its curative effect was very ***,the flowers of the flower of *** can be used as potential medicinal parts for *** that flavonoids are mostly found in flowers and exhibit a range of functions,it is possible to investigate the flowers in order to learn more about ***’s potential medical *** on botanical books,Chi

关键词： Gentiana macrophylla Pall basic source chemical component pharmacological activity quality control