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植保无人机雾滴飘移测试试验台设计及飘移性能分析

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农机化研究 2024年第5期46卷 175-181,196页

作者：杨晨升陈佳坪谢泽铭曹体智黑龙江科技大学机械工程学院哈尔滨150022 黑龙江省龙建路桥第一工程有限公司哈尔滨150028 黑龙江八一农垦大学工程学院黑龙江大庆163319

目前,我国对植保无人机研究主要集中在药液雾滴沉积、喷头结构分布及机具性能优化等方面。而对植保无人机施药技术更加透彻的理论分析还处于初级阶段,对精准施药方面如喷嘴技术参数、飞行作业最佳高度还没有统一参数标准,缺少标准的施... 详细信息

目前,我国对植保无人机研究主要集中在药液雾滴沉积、喷头结构分布及机具性能优化等方面。而对植保无人机施药技术更加透彻的理论分析还处于初级阶段,对精准施药方面如喷嘴技术参数、飞行作业最佳高度还没有统一参数标准,缺少标准的施药技术和作业规范,在不规范的作业参数下,喷雾质量极易受到影响、导致药液雾滴飘移并对周边作物生长环境造成破坏。针对上述问题,建立了植保无人机雾滴飘移测试试验台,研究植保无人机喷雾流场中不同旋翼转速下风场风速、喷雾压力对雾滴飘移运动的影响,并总结植保无人机喷雾施药作业中旋翼转速和喷雾压力的自身性能参数对雾滴飘移的影响规律。研究结果可为国内植保无人机喷雾施药技术优化发展提供基础理论参考。

关键词：植保无人机喷雾压力雾滴飘移规律旋翼转速

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石化污水处理场有机废气分类治理技术应用

炼油技术与工程 2024年第7期54卷 61-64页

作者：谢泽明许秋碧何晓礼廖昌建赵磊刘志禹中科(广东)炼化有限公司广东省湛江市524139 中石化(大连)石油化工研究院有限公司辽宁省大连市116045

根据不同废气源排放的废气流量与浓度的差异,将污水处理场有机废气分为5类,并采用低温柴油吸收-碱液吸收脱硫→脱硫及总烃浓度均化-催化氧化→洗涤-吸附→再生气催化氧化技术进行废气治理。废气1为中浓度VOCs(挥发性有机物)废气,密闭收... 详细信息

根据不同废气源排放的废气流量与浓度的差异,将污水处理场有机废气分为5类,并采用低温柴油吸收-碱液吸收脱硫→脱硫及总烃浓度均化-催化氧化→洗涤-吸附→再生气催化氧化技术进行废气治理。废气1为中浓度VOCs(挥发性有机物)废气,密闭收集后输送至脱硫及总烃浓度均化-催化氧化段处理;废气2和废气3为高浓度VOCs废气,需经过柴油吸收-碱液吸收脱硫预处理后再与废气1一同输送至催化氧化段处理;废气4和废气5为低浓度VOCs废气,送入洗涤-吸附处理,吸附尾气达标后排放,吸附剂饱和后使用催化氧化的高温净化气进行热再生,再生产生的高浓度尾气进入脱硫及总烃浓度均化-催化氧化单元进行处理。治理后净化气中非甲烷总烃质量浓度小于15 mg/m^(3),苯、甲苯与二甲苯浓度均满足排放限值要求,H_(2)S质量浓度低于10 mg/m^(3),净化气污染物排放浓度满足环保排放标准要求。

关键词：石化污水处理场有机废气低温柴油吸收碱液吸收脱硫总烃浓度均化催化氧化吸附

High Selectivity Cascaded Quadruplet Bandpass Filter with Three Pairs of Transmission Zeros

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Chinese Journal of Electronics 2017年第5期26卷 1101-1104页

作者： CHEN Jianfeng CHEN Fuchang LI Runshuo xie zeming CHU Qingxin School of Electronic and Information Engineering South China University of Technology

A novel microstrip Cascaded quadruplet(CQ) bandpass filter using quarter wavelength resonators and three-quarter wavelength resonators is *** on cross coupling and source-load coupling,three pairs of finite transmission zeros are generated at the *** a result,the out-of-band rejection can be enhanced and high selectivity is *** on the proposed structure,a cascaded quadruplet filter centering at 3.0GHz is designed and *** agreement between the measured and simulated data is obtained.

关键词： Cascaded quadruplet(CQ) Bandpass filter Cross coupling Transmission zeros Microstrip

用于抛物柱面空间功率合成天线的功分喇叭阵列

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强激光与粒子束 2011年第2期23卷 463-466页

作者：谢泽明张荣幸熊尚书华南理工大学电子与信息学院广州510640

提出了一种用于偏馈抛物柱面反射天线的功分喇叭。由于改善了口面上的电磁分布,该功分喇叭可以让馈源阵列的栅瓣电平抑制到-28 dB。用FEKO进行仿真发现,与传统用角锥喇叭阵列作为馈源的抛物柱面反射天线相比,使用功分喇叭直线阵列可以... 详细信息

提出了一种用于偏馈抛物柱面反射天线的功分喇叭。由于改善了口面上的电磁分布,该功分喇叭可以让馈源阵列的栅瓣电平抑制到-28 dB。用FEKO进行仿真发现,与传统用角锥喇叭阵列作为馈源的抛物柱面反射天线相比,使用功分喇叭直线阵列可以使空间功率合成天线的效率从68%提高到80%,同时天线的增益也能增加0.7 dB。

关键词：空间功率合成功分喇叭角锥喇叭偏馈抛物柱面天线口面利用效率

Bioinspired Scraper-File Type Frequency-Doubling Ultrasonic Exciter

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Journal of Bionic Engineering 2024年第4期21卷 1801-1816页

作者： Wenshuai Wu Mingshuo Zhang zeming Li Guang Yao Xinggang Jiang Deyuan Zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing100191China Institute of Bionic and Micro-Nano Systems Beihang UniversityBeijing100191China Guangdong Provincial Key Laboratory of Minimally Invasive Surgical Instruments and Manufacturing Technology Guangdong University of TechnologyGuangzhou510006China

In the natural world,leaf-cutting ants cause vibrations through their mutual scraping of file-scraper *** this study,we designed a Biomimetic Ultrasonic Exciter(BUE)that imitates leaf-cutting *** operating characteristics of the BUE were studied through experimental testing and finite element *** results showed that the BUE could generate stable ultrasonic vibrations,and that the excitation frequency only needed to be half the Output Frequency(OF).This frequency-doubling phenomenon was conducive to achieving BUE *** further explore the phenomenon of frequency-doubling vibration output,this study designed scrapers of five different sizes,conducted excitation and first-order natural frequency measurement tests,and the corresponding finite element *** was found that each scraper could operate in frequency-doubling mode,but the operating frequency and natural mode frequencies did not correspond with one *** further explicate experimental and simulation results,a two-degrees-of-freedom vibration model was *** was evident that the contact relationship between the dentate disc and scraper introduced strong nonlinear factors into the system,accounting for the frequency-doubling phenomenon and the difference between the BUE’s operating and mode *** BUE could be expected to facilitate the production of high-power micro-ultrasonic generators and has potential application value in the fields of mechanical processing,industrial production,and medical health.

关键词： Leaf-cutting ants Power ultrasound Nonlinear vibration Ultrasonic scalpel Micro vibrator

Improving hydrogen storage thermodynamics and kinetics of Ce-Mg-Ni-based alloy by mechanical milling with TiF_(3)

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Journal of Magnesium and Alloys 2024年第4期12卷 1593-1607页

作者： Hongwei Shang Wei Zhang Xin Wei Yaqin Li zeming Yuan Jun Li Yanghuan Zhang School of Mechanical and Electrical Engineering Chuzhou UniversityChuzhou 239000China Department of Functional Material Research Central Iron and Steel Research InstituteNo.76 Xueyuannan RoadHaidian DistrictBeijing 100081China Key Laboratory of Integrated Exploitation of Bayan-Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010China China Rare Earth New Material(Weishan)Co. Ltd.Jining 277600China

Mg-based hydrides are too stable and the kinetics of hydrogen absorption and desorption is not *** efficient way to improve these shortcomings is to employ reactive ball milling to synthesize the nanocomposite materials of Mg and *** this experiment,TiF_(3)was selected as an additive,and the mechanical milling method was employed to prepare the experimental *** alloys used in this experiment were the as-cast Ce_(5)Mg_(85)Ni_(10),as-milled Ce_(5)Mg_(85)Ni_(10)and Ce_(5)Mg_(85)Ni_(10)+3 wt.%*** phase transformation,structural evolution,isothermal and non-isothermal hydrogenation and dehydrogenation performances of the alloys were inspected by XRD,SEM,TEM,Sievert apparatus,DSC and *** revealed that nanocrystalline appeared in the as-milled *** with the as-cast alloy,ball milling made the particle dimension and grain size decrease dramatically and the defect density increase *** addition of TiF_(3)made the surface of ball milling alloy particles markedly coarser and more *** milling and adding TiF_(3)distinctly improved the activation and kinetics of the ***,ball milling along with TiF_(3)can decrease the onset dehydrogenation temperature of Mg-based hydrides and slightly ameliorate their thermodynamics.

关键词： Mg-based hydrides TiF_(3) Ball milling Thermodynamics Kinetics

Effect of Ball Milling Time on Microstructure and Hydrogen Storage Properties of Nd_(5)Mg_(41)Ni Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1201-1214页

作者： zeming Yuan Chenxu Liu Xiaoming Li Yongqi Sui Zhonggang Han Tingting Zhai Dianchen Feng Yanghuan Zhang Instrumental Analysis Center Inner Mongolia University of Science and TechnologyBaotou014010China Department of Functional Material Research Central Iron and Steel Research InstituteBeijing100081China

Mg-based alloys must be dehydrogenated at high pressure and temperatures, limiting their practical application. In this paper, Nd_(5)Mg_(41)Ni alloy was prepared by vacuum melting, and the as-cast alloy was ball milled for 5 h, 10 h, 15 h, and 20 h. The effect of ball milling time on the microstructure and hydrogen storage properties of the alloy was systematically studied. The alloy comprises Nd_(5)Mg_(41), NdMg_(12), NdMg_(3), and Mg_(2)Ni phases. The Nd_(5)Mg_(41)Ni alloy milling for 10 h can reach 95% of the saturated hydrogen absorption at 553 K by 40 s, and the alloy can desorb hydrogen only by 20 min. The dehydrogenation activation energy is only 99.9 kJ/mol H_(2). Ball milling makes the alloy produce many nanocrystalline and amorphous structures. The nano-grain boundary provides a channel for the diffusion of hydrogen atoms, and the high energy at the grain boundary provides energy for the phase deformation nucleus. Ball milling leads to the refinement of alloy particles and shortens the diffusion distance of hydrogen atoms to the interior of alloy particles. Defects such as twins and dislocations generated by milling provide energy for the phase deformation nucleus during the hydrogen absorption and desorption.

关键词： Hydrogen storage materials Magnesium-base alloy Ball milling Nanocrystal Kinetics

Effects of coal-fired power plants on soil microbial diversity and community structures

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Journal of Environmental Sciences 2024年第3期137卷 206-223页

作者： Bowen Sun Renbin Zhu Yu Shi Wanying Zhang zeming Zhou Dawei Ma Runfang Wang Haitao Dai Chenshuai Che Institute of Polar Environment&Anhui Key Laboratory of Polar Environment and Global Change School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China State Key Laboratory of Crop Stress Adaptation and Improvement School of Life SciencesHenan UniversityKaifeng 450046China State Grid Anhui Electric Power Research Institute Hefei 230601China

Long-term deposition of atmospheric pollutants emitted from coal combustion and their effects on the eco-environment have been extensively studied around coal-fired power ***,the effects of coal-fired power plants on soil microbial communities have received little attention through atmospheric pollutant deposition and ***,we collected the samples of power plant soils(PS),coal-stacking soils(CSS)and agricultural soils(AS)around three coal-fired power plants and background control soils(BG)in Huainan,a typical mineral resource-based city in East China,and investigated the microbial diversity and community structures through a high-throughput sequencing ***-stacking significantly increased(p<0.05)the contents of total carbon,total nitrogen,total sulfur and Mo in the soils,whereas the deposition of atmospheric pollutants enhanced the levels of V,Cu,Zn and ***,Actinobacteria,Thaumarchaeota,Thermoplasmata,Ascomycota and Basidiomycota were the dominant taxa in all *** bacterial community showed significant differences(p<0.05)among PS,CSS,AS and BG,whereas archaeal and fungal communities showed significant differences(p<0.01)according to soil samples around three coal-fired power *** predominant environmental variables affecting soil bacterial,archaeal and fungal communities were Mo-TN-TS,Cu-V-Mo,and organic matter(OM)-Mo,*** soil microbial genera were closely related to multiple key factors associated with stacking coal and heavy metal deposition from power *** study provided useful insight into better understanding of the relationships between soil microbial communities and long-term disturbances from coal-fired power plants.

关键词： Coal-fired power plants Soil microbial communities Coal-stacking Heavy metals Environmental variables

高原涡和西南涡影响的两次四川暴雨过程的对比分析

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大气科学 2019年第4期43卷 813-830页

作者：周玉淑颜玲吴天贻谢泽明中国科学院大气物理研究所云降水物理与强风暴重点实验室(LACS) 北京100029 高原大气与环境四川省重点实验室成都610225 南京信息工程大学气象灾害教育部重点实验室/气候与环境变化国际合作联合实验室/气象灾害预报预警与评估协同创新中心南京210044 金华市气象局浙江金华321000 中国科学院寒区旱区环境与工程研究所兰州730000

为了进一步研究高原涡、西南涡对西南地区暴雨的影响,本文用中国气象局自动站与CMORPH降水数据融合的逐时降水资料、国家卫星气象中心的逐时FY-2E卫星的云顶亮温(TBB)资料、欧洲气象资料中心(ERA-interim)的再分析资料,通过天气学诊断... 详细信息

为了进一步研究高原涡、西南涡对西南地区暴雨的影响,本文用中国气象局自动站与CMORPH降水数据融合的逐时降水资料、国家卫星气象中心的逐时FY-2E卫星的云顶亮温(TBB)资料、欧洲气象资料中心(ERA-interim)的再分析资料,通过天气学诊断分析方法以及拉格朗日轨迹模式HYSPLITv4.9,对发生在四川盆地的有高原涡东移影响西南涡发展引发暴雨的两次过程进行对比分析,发现:(1)两次暴雨过程的降水强度和分布有明显区别,并且TBB活动特征显示在过程一中有MCC(Mesoscale Convective Complex)的产生和发展,过程二则没有。(2)对于过程一,500 hPa上,高原涡逐渐减弱为高原槽并伸展到四川盆地上空,850 hPa上,在鞍型场附近有MCC的产生和发展,200 hPa上,高原涡在南亚高压北部偏西风急流下方的强辐散区内,位于南亚高压东南侧急流区下方稳定少动,偏东风急流北部有辐散中心,有利于西南涡的加强。对于过程二,500 hPa高原涡东移在四川盆地上空与西南涡耦合,形成一个稳定且深厚的系统,这也是过程二的暴雨强度比过程一强的最主要原因。200 hPa上,四川盆地始终位于南亚高压东侧的西北气流中,"抽吸作用"明显。(3)在过程一中,位涡逐渐东传且位涡增加的地方对应强降水区与MCC发展区,反映了暴雨和位涡的发展基本一致。在过程二中,中层位涡高值区从高原上东移并下传至盆地上空,两涡耦合使得上下层打通,位涡值比耦合之前单独的两涡强度更强。MCC产生的必要条件是中层大气要有强正涡度、强辐合和强上升运动,在未产生MCC前,过程一与过程二在盆地上空的动力条件甚至是相反的;从热力条件看,过程一中有明显的干冷空气入侵,增强不稳定条件,有利于MCC的产生并引发强降水;另一方面,本文也应证了二阶位涡的水平分布与暴雨落区有较好的对应关系。(4)通过拉格朗日方法的水汽轨迹追踪模式和聚类分析方法分析可得两次暴雨过程的水汽输送源地和通道也有明显区别,过程一主要有两条水汽通道,通道一来自阿拉伯海和孟加拉湾洋面的底层,通道二来自四川南部750 m以下高度;而过程二的主要水汽输送通道有三条,通道一来自西方地中海、黑海和里海上空1500~2500 m高度附近,通道二来自阿拉伯海和印度洋的底层,通道三的水汽从孟加拉湾低层绕过云贵高原直接输送到四川盆地。

关键词：高原涡西南涡四川盆地暴雨对比分析中尺度对流复合体(MCC) 水汽源