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地面仿真试验下的飞机倒飞故障分析研究

长沙航空职业技术学院学报 2024年第3期24卷 6-10页

作者：刘贤敏武颜俊国营芜湖机械厂安徽芜湖241007

针对地面仿真综合试验中飞机倒飞故障,对飞控联试环境、航电联试环境、仿真飞行机理进行了分析研究,并建立故障树。文章从通信协议、数据解析、信号干扰等方面开展了故障验证,并最终实现航电系统、飞控系统交联下的仿真飞行。该故障的... 详细信息

针对地面仿真综合试验中飞机倒飞故障,对飞控联试环境、航电联试环境、仿真飞行机理进行了分析研究,并建立故障树。文章从通信协议、数据解析、信号干扰等方面开展了故障验证,并最终实现航电系统、飞控系统交联下的仿真飞行。该故障的排除为后续跨系统综合试验平台的建设和运行提供了思路和建议。

关键词：飞机倒飞地面仿真交联故障

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潍坊市环境温度对人群非意外死亡风险的影响

环境与健康杂志 2024年第8期41卷 706-709页

作者：陈敏孟显峰金丽君刘娜郭明波潍坊市疾病预防控制中心慢性非传染性疾病防制科阳光融和医院关节外科

目的分析潍坊市2010—2022年环境温度与人群非意外死亡之间的关系，研究不适环境温度对人群死亡的影响。方法收集潍坊市2010—2022年气象数据与人群死亡数据，采用时间序列方法分析环境温度对该市非意外死亡风险的影响。结果 2010—2... 详细信息

目的分析潍坊市2010—2022年环境温度与人群非意外死亡之间的关系，研究不适环境温度对人群死亡的影响。方法收集潍坊市2010—2022年气象数据与人群死亡数据，采用时间序列方法分析环境温度对该市非意外死亡风险的影响。结果 2010—2022年潍坊市非意外死亡767 480例，其中慢性呼吸系统疾病死亡72 036例，心脑血管疾病死亡423 939例。2010—2022年潍坊市最适宜温度（即最低死亡率温度）为22.1℃。极低温对人群非意外死亡的风险累积效应值为1.285(95%CI:1.168～1.415)，极高温对人群非意外死亡的风险累积效应值为1.141(95%CI:1.076～1.209)；温度每升高1℃，非意外死亡的超额危险度为0.91%(95%CI:0.80%～1.02%)；温度对非意外总死亡的归因百分比为9.13%(95%CI:5.43%～12.92%)，其中低温对死亡的归因百分比高于高温，男性受温度影响的死亡效应低于女性，心脑血管疾病和慢性呼吸系统疾病受温度影响的死亡效应高于非意外总死亡。结论高温或低温均会增加人群非意外死亡风险，低温对于死亡的影响时间比高温长，应关注慢性呼吸系统疾病和心脑血管疾病等敏感人群。

关键词：非意外死亡不适环境温度最低死亡温度超额危险度

AN EXPERIMENTAL STUDY OF FLOW AROUND A BIO-INSPIRED AIRFOIL AT REYNOLDS NUMBER 2.0×10~3

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Journal of Hydrodynamics 2012年第3期24卷 410-419页

作者： SHI Sheng-xian LIU Ying-zheng CHEN Jian-min Key Laboratory of Education ministry for Power Machinery and Engineering School of Mechanical EngineeringShanghai Jiao Tong University Shanghai 200240 China

The fluid flow around a bio-inspired airfoil with corrugated surfaces and its smooth counterpart at chord Reynolds number Re = 2.0×10^3. and different Angle-Of-Attack （AOA = 0°, 4°, 8° and 12°） were measured by using Particle Image Velocimetry （PIV）. The global characteristics of the fluid flow around two airfoils were analyzed by ensemble-averaged velocity field, distribution of reverse flow intermittency, and time-series flow visualizations. At AOA = 0°, no significant variation of the global flow patterns was recognized for both configurations. The statistical results of reverse flow intermittency results demonstrated that the protruding peaks of the corrugated airfoil delay flow separation occur at AOA = 4°. At large AOAs （8° and 12°）, however, the flow is massively separated in both configurations, the combination of large separation bubble above the corrugated airfoil and small recirculation zones in the upstream upper valley results in earlier separation of the flow. At AOA=8°, the wake region behind the corrugated airfoil is considerably shortened in comparison to the smooth one, indicating a remarkable reduction of the time-mean lift and drag forces, however, at AOA - 12°, the wake region behind the corrugated one is slightly larger than that behind the smooth one. For the case of AOA = 8° and 12°, the time-series flow visualizations demonstrate the intensified vortex shedding process of the corrugated airfoil, which would give rise to enhanced dynamic loading. Due to the fact that dragonfly wing is practically flexible, it is speculated that the wing structure of a gliding dragonfly might be sophisticatedly deformed in response to the periodic loading to reduce the drag.

关键词： corrugated airfoil separated flow Particle Image Velocimetry (PIV) dragonfly gliding flight

“一带一路”沿线省份绿色物流效率及影响因素研究

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供应链管理 2024年第2期5卷 58-70页

作者：贾县民徐蓉谭佳信西安财经大学管理学院陕西西安710100

“一带一路”倡议推动了我国与沿线各国之间贸易的飞速发展。物流业虽然是“一带一路”沿线国家(地区)互联互通的支柱力量,但同时也是高污染、高耗能、高排放行业,影响我国“一带一路”高质量发展。提升“一带一路”沿线省份绿色物流效... 详细信息

“一带一路”倡议推动了我国与沿线各国之间贸易的飞速发展。物流业虽然是“一带一路”沿线国家(地区)互联互通的支柱力量,但同时也是高污染、高耗能、高排放行业,影响我国“一带一路”高质量发展。提升“一带一路”沿线省份绿色物流效率势在必行。文章基于“一带一路”沿线省份2011年至2020年数据,运用超效率SBM模型与Malmquist指数模型对绿色物流效率进行测度,并选用Tobit回归模型对其影响因素进行分析。“一带一路”沿线省份绿色物流发展仍存在区域发展不平衡等问题;东南区域静态效率最高,西南区域动态改善情况最好;经济水平、物流资源利用率、产业结构及物流业劳动生产率积极影响沿线省份绿色物流效率的提高,能源结构、物流业集聚水平则起到抑制作用。提出调整能源消费结构、搭建物流信息化平台、加强“碳引导”和政策激励力度、推动区域物流协调发展等建议。

关键词：一带一路绿色物流效率超效率SBM Malmquist指数 Tobit模型

Effect of Microstructures on Elevated-Temperature Wear Resistance of a Hot Working Die Steel

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Journal of Iron and Steel Research International 2011年第10期18卷 47-53页

作者： WEI min-xian WANG Shu-qi WANG Lan CHEN Kang-min School of Materials Science and Engineering Jiangsu University Zhenjiang 212013 Jiangsu China

Elevated-temperature wear tests under atmospheric conditions at 400 ℃ were performed for a hot working die steel H21 on a pin-on-disk wear tester. The phase and morphology of worn surfaces were examined using XRD and SEM, and the relation of wear resistance to tempered microstructures was studied for H21 steel. XRD patterns exhibit that oxidative wear is a predominated wear mechanism with Fe3O4 and Fe2O3 on worn surfaces. It is found that with increasing normal load, obvious plastic deformation of substrate appears on worn surfaces. Microstructures start to affect apparently wear resistance of the steel with an increase of load. Under loads of 50--100 N, wear losses of steel retain low values and relatively approach for steels with various microstructures. As loads are increased to 150--200 N, wear losses of steel start to increase obviously and present apparent difference for steel with various microstructures. Wear resistance is found to increase in the sequence as follows., tempered sorbite, tempered martensite, tempered troostite without secondary hardening and tempered troostite with secondary hardening or upcoming one. Higher strength and microstructural stability are required for steels with excellent wear resistance.

关键词： steel heat treatment microstructure wear wear resistance

黄毛耳草中东莨菪内酯的HPLC含量测定及提取工艺优化研究

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宜春学院学报 2024年第6期46卷 17-20,125页

作者：金贤武周燕霞上饶市检验检测认证院药品检测分院江西上饶334000 江西医学高等专科学校药学院江西上饶334000

目的:建立黄毛耳草中东莨菪内酯的HPLC含量测定方法,并优化其提取工艺。方法:色谱柱waters symmetry C_(18)(4.6 mm×250 mm,5μm),流动相乙腈0.1%磷酸水,检测波长345 nm,流速0.8 mL/min,进样量10μL,测定东莨菪内酯含量。采用超声提取... 详细信息

目的:建立黄毛耳草中东莨菪内酯的HPLC含量测定方法,并优化其提取工艺。方法:色谱柱waters symmetry C_(18)(4.6 mm×250 mm,5μm),流动相乙腈0.1%磷酸水,检测波长345 nm,流速0.8 mL/min,进样量10μL,测定东莨菪内酯含量。采用超声提取法,以乙醇浓度、超声时间、超声功率和料液比为考察因素,以东莨菪内酯含量为评价指标,优化其提取工艺。结果:最佳提取工艺为乙醇浓度74%、提取时间45 min、超声功率250 W、液料比25∶1。精密称取3份黄毛耳草样品,每份2.0 g,此条件下东莨菪内酯的提取含量为为81.97μg/g,与预测值81.41μg/g无显著性差异。结论:本试验建立的HPLC法可用于黄毛耳草中东莨菪内酯的含量测定,所优化的提取工艺稳定可靠、简便可行。

关键词： HPLC Box Behnken响应面黄毛耳草东莨菪内酯工艺优化

All-Optical Cesium Atomic Magnetometer with High Sensitivity

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Chinese Physics Letters 2012年第6期29卷 280-282页

作者： ZHANG Jun-Hai LIU Qiang ZENG xian-jin LI Jiu-Xing SUN Wei-min Science School Harbin Engineering UniversityHarbin 150001 Colleges of Electronic Science Northeast Petroleum UniversityDaqing 163318

An all-optical cesium magnetometer with high sensitivity based on absorptive detection is *** experiment achieves a polarized rotational spectrum of the probe light which is induced by circular dichroism and a quarter wave plate *** frequency response of the rotational spectrum is 1.8mrad/Hz at Larmor precession *** the signal-to-noise ratio from the experimentally observed spectrum,we predict that the magnetic measurement sensitivity of 0.3pT/Hz^(1/2) would be obtained in the responsive range from 20nT to 2000nT.

关键词： spectrum magnetometer polarized

Electrochemical regioselective synthesis of N-substituted/unsubstituted 4-selanylisoquinolin-1(2H)-ones

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Chinese Chemical Letters 2022年第3期33卷 1501-1504页

作者： Zhi-Lin Wu jin-Yang Chen xian-Zhi Tian Wen-Tao Ouyang Zhuo-Tao Zhang Wei-min He School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China

A novel and efficient electro-chemical initiated radical strategy was developed for the preparation of both N-substituted and N-unsubstituted 4-selanylisoquinolin-1(2H)-ones through selenylation of isoquinolin-1(2H)-o... 详细信息

关键词： Organodiselenide Electrochemistry Radical Atom economy Additives-free

超细铂纳米催化剂的光化学合成及其催化还原硝基苯酚的应用

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中山大学学报（自然科学版）（中英文） 2024年第3期63卷 137-146页

作者：鲜亮田小霞马婧李伟西北民族大学化工学院甘肃兰州730030 甘肃省高校环境友好复合材料及生物质利用省级重点实验室甘肃兰州730030

以乙二醇(EG)为还原剂,通过波长为395 nm近紫外光和450、650 nm的可见光照射C_(60)及K_(2)[PtCl_(4)]混合液,制备了超细铂纳米颗粒(Pt/C_(60)-E)。利用X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、X射线光电子能谱(XPS)以及高分辨率透... 详细信息

以乙二醇(EG)为还原剂,通过波长为395 nm近紫外光和450、650 nm的可见光照射C_(60)及K_(2)[PtCl_(4)]混合液,制备了超细铂纳米颗粒(Pt/C_(60)-E)。利用X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、X射线光电子能谱(XPS)以及高分辨率透射电子显微镜(HR-TEM)等表征手段对Pt/C_(60)催化剂的组成及形貌进行了研究,结果表明,铂纳米颗粒在C_(60)表面分散良好,平均粒径约为2.6 nm。在催化p-NP还原实验中,在近紫外光(395 nm)照射下所制备催化剂(Pt/C_(60)-E3)表现出最高的催化活性,其速率常数k=0.12 min^(-1)。在催化剂循环实验中,多次循环催化剂仍具有较高的活性,实验证明光化学法对前驱体铂催化剂制备起到良好的作用。

关键词：超细铂纳米颗粒富勒烯光化学法降解p-硝基苯酚