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Spraying Arginine at 5 Days before Harvest Delays Postharvest Broccoli Senescence via Nutrient Accumulation
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作者 SUN Yupeng CHEN Ying +4 位作者 SHANG Qingwen GUO Yanyin ZHANG Yuxiao WANG Yunqiao XUE Qingyue 《食品科学》 EI CAS 北大核心 2025年第1期131-141,共11页
To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conduct... To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conducted at 0,1,3,and 5 days before harvest.The appearance,respiration rate,mass-loss rate,electrolyte leakage,glucosinolate,ascorbic acid,total phenol,total flavonoid,total sugar and sucrose contents,and sucrose phosphate synthase(SPS),invertase(INV),sucrose synthase synthesis(SSS)and cleavage(SSC)activities of broccoli samples were observed after 0,2,4,6,8,and 10 days of storage.The results showed that spraying arginine at 5 days preharvest(5-ARG)helped to inhibit broccoli respiration during storage,delay electrolyte leakage,and maintain broccoli color.Furthermore,during the growth stage,total sugar accumulation was higher in the 5-ARG group.In addition,during the storage period,sucrose synthesis was accelerated,while sucrose cleavage was inhibited,resulting in more sucrose retention in postharvest broccoli.In conclusion,5-ARG resulted in the accumulation of more nutrients during the growth process and effectively delayed the quality decline during storage,thereby prolonging the shelf life of broccoli.Therefore,this study provides a theoretical basis for improving postharvest storage characteristics of broccoli through preharvest treatments. 展开更多
关键词 ARGININE BROCCOLI preharvest spraying nutrient accumulation storage quality postharvest senescence
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Preparation of Si/NC/CL-20 Composite Explosives by Electrostatic Spraying Method and Its Performance Characterization
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作者 DUAN Yi-long WANG Ling-xin +3 位作者 DONG Jun LI Xiu-long HE Xi JI Wei 《火炸药学报》 北大核心 2025年第5期424-429,I0001,共7页
To study the influence of silicon(Si)on 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20),NC/CL-20 composite explosives and Si/NC/CL-20 composite explosives were prepared by the electrostatic spraying ... To study the influence of silicon(Si)on 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20),NC/CL-20 composite explosives and Si/NC/CL-20 composite explosives were prepared by the electrostatic spraying method.The morphology,structure and thermal decomposition properties of the samples were analyzed using scanning electron microscopy(SEM),X-ray energy spectroscopy(EDS),infrared spectroscopy(FT-IR),and simultaneous thermal analyzer(TG-DSC).Additionally,the combustion process of the samples was tested using a high-speed camera.The results show that the addition of nano-Si contributes to the formation of composite explosives with regular morphology and smaller particle size.The Si/NC/CL-20 composite explosive has better and more uniform sphericity,with an average particle size of 73.4 nm,compared to the NC/CL-20 composite explosive.The Si/NC/CL-20 composite explosive which produced by the electrostatic spraying method,achieves physically uniform distribution of the components including NC,CL-20,Si.The addition of Si promotes the thermal decomposition of CL-20.In comparison to the NC/CL-20 composite explosive,the activation energy of the Si/NC/CL-20 composite explosive decreases by 16.78 kJ/mol,and the self-accelerated decomposition temperature and the critical temperature of thermal explosion decreases by 3.12 K and 2.61 K,respectively.Furthermore,Si/NC/CL-20 composite explosive has shorter ignition delay time and faster combustion rate compared to the NC/CL-20 composite explosive,which shows that Si can improve the combustion performance of CL-20. 展开更多
关键词 applied chemistry electrostatic spraying method SI Si/NC/CL-20 thermal decomposition performance combustion performance
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Overview of Automatic Spraying Technology for Building Exterior Walls
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作者 Jianheng Chen 《Journal of Electronic Research and Application》 2025年第1期100-105,共6页
The spraying robot for building exterior walls is an innovative technology in the field of modern construction.This paper discusses its design structure,application cases,technical benefits,and industrial impacts.Rese... The spraying robot for building exterior walls is an innovative technology in the field of modern construction.This paper discusses its design structure,application cases,technical benefits,and industrial impacts.Research shows that this type of robot improves the efficiency and quality of exterior wall construction.Its intelligent design enhances operation accuracy and safety,reduces costs and risks,and strengthens application ability in complex environments,showing broad application prospects and symbolizing the development trend of intelligence and automation in the industry.In the future,it is necessary to strengthen its intelligence and adaptive ability further,explore multi-function design,promote automation technology,and ensure construction safety and economic benefits. 展开更多
关键词 BUILDING Exterior walls spraying ROBOT AUTOMATION
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Microstructure,mechanical property,reciprocating sliding wear and electrochemical corrosion of AlCoCrFeNi high entropy alloy coatings with Si addition prepared by HVOF spraying
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作者 Qiang Da Jia-jie Kang +6 位作者 Guo-zheng Ma Yong-kuan Zhou Zhi-qiang Fu Li-na Zhu Ding-shun She Jian Liang Hai-dou Wang 《Journal of Iron and Steel Research International》 2025年第5期1302-1319,共18页
AlCoCrFeNi and AlCoCrFeNiSi high entropy alloy(HEA)coatings have been prepared by high velocity oxygen fuel spraying,and the microstructure,mechanical properties as well as wear behaviors of the two HEA coatings were ... AlCoCrFeNi and AlCoCrFeNiSi high entropy alloy(HEA)coatings have been prepared by high velocity oxygen fuel spraying,and the microstructure,mechanical properties as well as wear behaviors of the two HEA coatings were studied.With Si element addition,the surface and cross-sectional microstructure of HEA coating are refined,and it was found that both HEA coatings have a body-centered cubic structure,and the X-ray diffraction peaks of AlCoCrFeNiSi HEA coating deviate to the right.The microhardness,bonding strength nanohardness and elastic modulus of AlCoCrFeNi HEA coating increased with addition of Si element due to the fact that Si promotes uniformly distribution of other elements.In terms of wear properties,coefficient of friction and the wear rate were reduced with Si element addition,and the two HEA coatings have similar wear mechanism at the same loads.And at lower loads,the wear mechanism is abrasive wear,adhesive and slight oxidative wear,it is turn to oxidative wear and severe abrasive wear while the load is increased.The AlCoCrFeNiSi HEA coating has a higher corrosion potential and a lower corrosion current density,indicating improved corrosion resistance.This enhancement is attributed to the presence of Si,which reduces interatomic spacing and results in a more compact atomic arrangement.Consequently,element migration and chemical reactions are reduced,leading to the formation of a denser and more uniform passivation film. 展开更多
关键词 High entropy alloy coating AlCoCrFeNi alloy Wear mechanism High velocity oxygen fuel spraying Corrosion
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无人机施药雾滴粒径与喷液量对稻飞虱防治的影响
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作者 曾文 李子睿 +3 位作者 尹佳林 丁家浩 饶余斌 邓继忠 《中国农机化学报》 北大核心 2026年第1期153-159,共7页
为分析植保无人机(UAV)施药时,雾滴粒径和喷液量对水稻冠层的雾滴沉积及防治稻飞虱效果的影响,采用P40型植保无人机在水稻分蘖末期喷施吡蚜酮防治稻飞虱,开展2种喷液量(15 L/hm^(2)和22.5 L/hm^(2))、3种雾滴粒径(105μm、135μm和150... 为分析植保无人机(UAV)施药时,雾滴粒径和喷液量对水稻冠层的雾滴沉积及防治稻飞虱效果的影响,采用P40型植保无人机在水稻分蘖末期喷施吡蚜酮防治稻飞虱,开展2种喷液量(15 L/hm^(2)和22.5 L/hm^(2))、3种雾滴粒径(105μm、135μm和150μm)的水稻冠层雾滴沉积试验及田间药效试验,并与背负式电动喷雾器(KES)人工施药的常规防治方法进行施药效果对比。雾滴沉积试验结果表明,雾滴粒径对冠层底部的雾滴沉积量有显著影响,雾滴粒径越大,雾滴沉积量越大;15 L/hm^(2)和22.5 L/hm^(2)两种喷液量下,冠层底部的雾滴沉积量没有显著差异。药效试验结果表明,施药后1天和7天,雾滴粒径对稻飞虱防治效果有显著影响,雾滴粒径越大,防治效果越好;施药后14天,3种雾滴粒径的防治效果没有显著差异;15 L/hm^(2)和22.5 L/hm^(2)两种喷液量的防治效果在施药后1天、7天和14天差异均不显著。采用植保无人机施药防治稻飞虱,增大雾滴粒径有利于水稻冠层底部的雾滴沉积,并提高稻飞虱防治效果;低容量喷雾时,增加喷液量对水稻冠层底部的雾滴沉积和稻飞虱防治效果没有显著影响。 展开更多
关键词 无人机 喷雾 雾滴粒径 雾滴沉积 喷液量 稻飞虱
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基于点云的复杂工件机器人喷涂方法
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作者 王化明 沈颖 +1 位作者 姜少华 徐轲 《江苏大学学报(自然科学版)》 北大核心 2026年第1期25-30,共6页
针对示教喷涂机器人在面对多品种小批量工件时适应性差的问题,研究一种基于3D点云模型参数化重建的复杂工件机器人喷涂方法.采用线激光视觉传感器扫描工件得到其3D点云,去除点云中背景及挂钩以分割工件点云,在工件点云主矢量方向投影并... 针对示教喷涂机器人在面对多品种小批量工件时适应性差的问题,研究一种基于3D点云模型参数化重建的复杂工件机器人喷涂方法.采用线激光视觉传感器扫描工件得到其3D点云,去除点云中背景及挂钩以分割工件点云,在工件点云主矢量方向投影并切片以获得工件尺寸,进行工件的参数化建模.根据工件特征表面的类型,将凹面和具有复连通区域的面分解为封闭的凸面,采用扫描线法生成喷涂路径并进行机器人轨迹规划.构建机器人喷涂系统,多次测试表明:系统能基于工件点云进行三维模型重建及机器人轨迹规划,机器人能沿规划轨迹运动,对工件悬挂位姿要求不敏感,满足工件喷涂的实际需求. 展开更多
关键词 机器人 点云 参数化建模 轨迹规划 喷涂系统
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Corrosion resistance of Fe-based amorphous metallic matrix coating fabricated by HVOF thermal spraying 被引量:17
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作者 王善林 成京昌 +1 位作者 李承勋 柯黎明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第1期146-151,共6页
The Fe-based amorphous metallic matrix coating (Fe-AMMC) was fabricated with the powder mixtures of Fe-based metallic glass synthesized with industrial raw materials, NiCr alloy and WC particle by high velocity oxy-... The Fe-based amorphous metallic matrix coating (Fe-AMMC) was fabricated with the powder mixtures of Fe-based metallic glass synthesized with industrial raw materials, NiCr alloy and WC particle by high velocity oxy-fuel (HVOF) spraying. The corrosion resistance of Fe-AMMC was investigated by potentiodynamic polarization tests in 1 mol/L HCl, NaCl, H2SO4 and NaOH solutions, respectively. The surface morphologies corroded were observed by SEM. The results indicate that Fe-AMMC exhibits excellent corrosion resistance, higher corrosion resistance than 304L stainless steel in the chloride solutions. The low corrosion current density and passive current density of Fe-AMMC with a wide spontaneous passivation region are about 132.0μA/cm2 and 9.0 mA/cm2 in HCl solution, and about 2.5 μA/cm2 and 2.3 mA/cm2 in NaCl solution. The excellent corrosion resistance demonstrates that Fe-based amorphous metallic matrix powder is a viable engineering material in practical anti-corrosion and anti-wear coating applications. 展开更多
关键词 Fe-based metallic glass COATING corrosion resistance HVOF spraying
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Effects of Spraying Nitrogen and Zinc Fertilizers after Flowering on Grain Weight and Nutritional Quality of Winter Wheat 被引量:2
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作者 左毅 马冬云 +2 位作者 马英 张斌 郭天财 《Agricultural Science & Technology》 CAS 2013年第4期630-634,650,共6页
In order to explore the effect of spraying fertilizers after flowering on grain weight and nutritional quality of different winter wheat cultivars, twenty wheat culti- vars in wheat zones along Yellow River and Huai R... In order to explore the effect of spraying fertilizers after flowering on grain weight and nutritional quality of different winter wheat cultivars, twenty wheat culti- vars in wheat zones along Yellow River and Huai River, were used to investigate the change of thousand kernel weight (TKW), phytic acid content (PAC), contents of Fe, Zn and Mg and bioavailability by spraying zinc and nitrogen fertilizers after flowering. The results showed that both of TKW and protein content in grains in- creased by spraying Zn and N fertilizers, and the effect of N fertilizer proved more significant. The PAC decreased significantly after Zn treatment, for example, PAC of "955159", a wheat cultivar, decreased by 27.95%. However, PAC was in- significantly influenced by N fertilizer. On the other hand, Zn content in wheat grains were improved after spraying Zn fertilizer and the increase aveaged 54.38%. Furthermore, Fe and Zn contents grew significantly after spraying N fertilizer, and the increase averaged 36.88% and 11.25% respectively. However, Mg content in grains declined by N fertilizer. Still, the bioavailability of zinc in grains was enhanced after spraying Zn fertilizer, and of Fe was also increased greatly after spraying N fertilizer. In conclusion, grain weight, and content and effectiveness of mineral ele-ments can be improved simultaneously by rational spraying of N and Zn fertilizers to improve quality of grains. 展开更多
关键词 Winter wheat spraying fertilizer after flowering Nitrogen and zinc fertil- izers Grain weight Nutrient elements
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Application of New Slope Greening Technology——Reinforced Organic-Material and Plant Seeds Spraying 被引量:1
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作者 李国庆 阴磊 吴云天 《Agricultural Science & Technology》 CAS 2014年第1期152-154,共3页
The research introduced the flowchart of organic-material and plant seeds spraying and a case of &quot;Dasi&quot; Highway, the highway from Daxing to Sinan in Guizhou Province, a part of a National Highway from Hang... The research introduced the flowchart of organic-material and plant seeds spraying and a case of &quot;Dasi&quot; Highway, the highway from Daxing to Sinan in Guizhou Province, a part of a National Highway from Hangzhou to Ruili, cal ed Hangrui Highway, slope protection. The flowchart included slope cleaning, net preparation, anchor fixation, adding vegetation-growth plate, spraying organic materi-als, coverage of non-woven fabrics, and maintenance. The technique is proved much efficient in protecting and greening road sideslopes consisting of weathered rocks or hard rocks, which provides a solution for abrupt slope greening technology. 展开更多
关键词 SLOPE GREENING Organic materials Reinforced and plant seeds spraying
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Studies on GA_3 Spraying Dosage for eui TGMS Rice Changxuan 3S in Its Hybrid Seed Production 被引量:2
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作者 肖辉海 王文龙 郝小花 《Agricultural Science & Technology》 CAS 2010年第6期61-64,共4页
[Objective] Changxuan 3S was thermo-sensitive genicmale sterile(TGMS)rice selected from irradiated seeds of Peiai 64S by 350 Gy^(60)Coγ-ray.The aim of the study was to confirm GA3 spraying dosage of Changxuan 3S ... [Objective] Changxuan 3S was thermo-sensitive genicmale sterile(TGMS)rice selected from irradiated seeds of Peiai 64S by 350 Gy^(60)Coγ-ray.The aim of the study was to confirm GA3 spraying dosage of Changxuan 3S with eui gene in its hybrid seed production.[Method] Changxuan 3S possessing eui gene and its parent Peiai 64S were chosen as materials.Comparison studies on sensitivity to GA3 in their hybrid seed production were carried out.[Result] The suitable stage for spraying GA3 in the hybrid seed production of Changxuan 3S was at 10% of panicles headed;The optimal dosage was 90 g/hm2 with 2 split sprayings,the first spraying of 45 g/hm2 at heading of 10% panicles and the second one of 45 g/hm2 on the following day.Under the condition of spraying GA3 at the rate of 90 g/hm2,the panicle neck exsertions of Changxuan 3S was +1.78 cm,and exserted stigma rate and seed setting rate of Changxuan 3S were 96.87% and 36.44%,being 21.46% and 16.33% more than those of Peiai 64S,respectively.The theoretical yield of "Changxuan 3S/9311" reached 2 931.90 kg/hm2,which was increased by 1 259.40 kg/hm2 comparing with "Peiai 64S/9311".[Conclusion] Compared with Peiai 64S,Changxuan 3S is more sensitive to GA3,which results in no or little using GA3 in seed production of Changxuan 3S.Moreover,Changxuan 3S showed higher yield potential than Peiai 64S. 展开更多
关键词 Rice(Oryza sativa L.) Thermo-sensitive genic male sterile(TGMS)line Elongayed uppermost internode(eui) Changxuan 3S GA3 spraying dosage
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植保无人机核心技术研究现状与发展趋势
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作者 尹园 张燕梁 +4 位作者 张庆柱 马永财 孙锦秀 李尧 李菁 《农机化研究》 北大核心 2026年第4期284-292,共9页
随着我国农业航空技术的不断进步,植保无人机凭借其广泛的适用性、高效的作业能力、安全的施药方式,已广泛应用于大田作物、经济作物和林业等领域的农药喷施,并在病虫害防治工作中逐渐成为农业航空产业的重要组成部分。然而,实际作业时... 随着我国农业航空技术的不断进步,植保无人机凭借其广泛的适用性、高效的作业能力、安全的施药方式,已广泛应用于大田作物、经济作物和林业等领域的农药喷施,并在病虫害防治工作中逐渐成为农业航空产业的重要组成部分。然而,实际作业时植保无人机需应对复杂的飞行和喷施任务,为确保高质量、精准地完成任务,对其核心技术提出了更高的要求。为此,深入探讨了植保无人机的核心技术(包括导航系统、姿态控制方法、路径规划方法、雾滴沉积、雾滴漂移和变量喷施技术等)的研究现状与发展趋势,旨在为植保无人机的研发提供有益参考,并助力农业装备的智能化发展。 展开更多
关键词 植保无人机 病虫害防治 农药喷施 核心技术
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Growth of CuI buffer layer prepared by spraying method
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作者 阎有花 刘迎春 +3 位作者 方玲 卢志超 李正邦 周少雄 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第2期359-363,共5页
CuI thin films with nano-scale grains of about 35nm were deposited via spraying method with using acetonitrile as solvent. The influence of iodine doping concentration in acetonitrile solution on the structure, topogr... CuI thin films with nano-scale grains of about 35nm were deposited via spraying method with using acetonitrile as solvent. The influence of iodine doping concentration in acetonitrile solution on the structure, topographic and optical properties of CuI thin films was investigated. X-ray diffraction results showed that CuI iodine-doped films doped CuI:I2 were in γ-phase of zinc blende structure with (111) preferential plane. Scanning electron microscopy revealed that the microstructure of CuI films depended on the relative amount of doping iodine in the solution. When the iodine doping amount in acetonitrile solution was 0.025 g, the film was uniform and compact, the optical transmittance was 75.4% in the part of visible region and the energy band gap was close to 2.96 eV. 展开更多
关键词 CuI thin film buffer layer spraying method iodine doping
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我国果园施药技术与配套地面装备研究进展
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作者 肖文 徐陶 +3 位作者 祁雁楠 李雪 赵志国 吕晓兰 《中国农机化学报》 北大核心 2026年第1期258-265,共8页
果园施药装备是植保机械中的重要分支,其性能和作业质量直接影响果园病虫害防治效果。综合分析我国果园施药技术的研究进展,包括气流辅助喷雾技术、静电喷雾技术、循环喷雾技术和精准变量施药技术,分别对其工作原理、存在问题等进行阐述... 果园施药装备是植保机械中的重要分支,其性能和作业质量直接影响果园病虫害防治效果。综合分析我国果园施药技术的研究进展,包括气流辅助喷雾技术、静电喷雾技术、循环喷雾技术和精准变量施药技术,分别对其工作原理、存在问题等进行阐述;并以果园风送喷雾机为主,按照动力供给方式将其分为自走式、牵引式和悬挂式,分析我国果园施药装备的研究进展,深入探讨我国喷雾机关键部件的研究现状。指出我国果园施药技术、农机农艺融合程度、推广研发力度和适应性等方面存在的问题,提出未来我国果园植保喷雾机在施药技术创新、果园宜机化改造及装备智能化发展方面的研发思路,为我国果园施药装备智能化、精细化、高效绿色作业的发展提供参考。 展开更多
关键词 果园 施药技术 喷雾机 地面装备 精准施药
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SIMULATION OF FLUIDIZED BED WITH TOP LIQUID SPRAYING
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作者 王春艳 马国平 许锡恩 《Transactions of Tianjin University》 EI CAS 1999年第2期83-87,共5页
Simulation of the drying process in a top spraying fluidized bed is conducted.A wetting coefficient describing the wetted part of the particle surface is introduced.Using experimental data and the data regression met... Simulation of the drying process in a top spraying fluidized bed is conducted.A wetting coefficient describing the wetted part of the particle surface is introduced.Using experimental data and the data regression method,the modified function of the wetting coefficient is calculated.And this function is introduced to the mathematical model,which describes the heat and mass transfer process in a liquid sprayed gas fluidized bed.Through modeling,the gas humidity and temperature profiles as well as the particle temperature profile can be obtained.Compared with the experimental results,the wetting coefficient and the mathematical model are verified. 展开更多
关键词 fluidized bed with top spraying wetting coefficient particle coating
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环境温度与压力对HFE7100制冷剂单液滴蒸发特性的影响机制研究
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作者 印晶 刘艺 +2 位作者 Leslie K.NORVIHOHO 陈斌 周致富 《西安交通大学学报》 北大核心 2026年第1期107-116,共10页
为系统研究环境温度与压力对环保型制冷剂HFE7100单液滴蒸发特性的影响机制,基于挂滴法,结合高速摄像与热电偶测温技术,同步观测液滴形态与内部温度变化。试验结果表明,HFE7100单液滴蒸发特性受环境温度(50、100、150、200、250℃)与压... 为系统研究环境温度与压力对环保型制冷剂HFE7100单液滴蒸发特性的影响机制,基于挂滴法,结合高速摄像与热电偶测温技术,同步观测液滴形态与内部温度变化。试验结果表明,HFE7100单液滴蒸发特性受环境温度(50、100、150、200、250℃)与压力(1、10、20 bar)的显著影响。在高温(>100℃)下,液滴蒸发呈双阶段特征,即初始加热阶段和平衡蒸发阶段,而50℃低温下仅表现为单阶段平衡蒸发。在250℃时,因组分沸点差异较小可观察到气泡形成与破裂,但对蒸发的促进作用有限,且高压(10、20 bar)会显著减小气泡尺寸。高温通过提高气液相传热强度、饱和蒸气压及气相扩散系数,显著加速液滴升温与蒸发,导致初始加热阶段占比增加。此外,环境压力对蒸发特性的影响取决于环境温度。在50℃低温下,压力升高因抑制蒸汽扩散而降低蒸发速率常数;而在150、200、250℃高温下,压力通过降低气化潜热和增强对流传热加速液滴升温,反而提升蒸发速率常数。这些效应(促进液滴升温与抑制蒸汽扩散)相互竞争,最终决定了环境压力对液滴蒸发的影响。该发现为喷雾冷却技术的优化提供了重要的理论依据。 展开更多
关键词 HFE7100制冷剂 液滴蒸发 喷雾冷却 环境温度 环境压力
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太阳能光热发电吸热器管屏涂层检测攀爬机器人的设计与仿真
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作者 张虔 张星 +1 位作者 龚巍 程义 《锅炉制造》 2026年第1期40-43,46,共5页
针对太阳能光热发电吸热器管屏高空涂层检测和高空喷涂的难题,分析其需求,设计一种攀爬机器人和三段行程缩放机构;建立攀爬机器人的整体模型,并对攀爬步态进行规划;基于步态分析,对机器人夹持器的电机运行参数进行设定;利用Adams软件对... 针对太阳能光热发电吸热器管屏高空涂层检测和高空喷涂的难题,分析其需求,设计一种攀爬机器人和三段行程缩放机构;建立攀爬机器人的整体模型,并对攀爬步态进行规划;基于步态分析,对机器人夹持器的电机运行参数进行设定;利用Adams软件对夹持器进行运动学分析,研究夹持器的位移情况,验证夹持器电机运行参数的正确性。仿真结果表明,该涂层检测和喷涂机器人能够以拟定的步态实现攀爬过程,同时验证了所设定的电机运动参数是正确的。 展开更多
关键词 太阳能 吸热器管屏 喷涂机器人 仿真 步态分析
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基于改进YOLOv7的植保无人机精准喷洒系统
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作者 陈文彬 傅晓锦 +2 位作者 江志伟 王瑞 卢犇轶 《中国农机化学报》 北大核心 2026年第1期167-173,共7页
对于当前植保无人机喷洒存在重复喷洒、农药残留、缺少在线病虫害检测,且检测方法不易在嵌入式端部署等问题,提出一种植保无人机平台下基于改进YOLOv7的霜霉病与潜叶蝇检测农药喷洒系统。首先,采用渐进金字塔网络AFPN提升模型在特征融... 对于当前植保无人机喷洒存在重复喷洒、农药残留、缺少在线病虫害检测,且检测方法不易在嵌入式端部署等问题,提出一种植保无人机平台下基于改进YOLOv7的霜霉病与潜叶蝇检测农药喷洒系统。首先,采用渐进金字塔网络AFPN提升模型在特征融合区域的自适应特征融合能力。其次,引入EMA注意力机制模块,利用维度交互的方式来提升融合像素特征。试验结果表明,改进YOLOv7病虫害检测算法的平均精度均值mAP达到94.2%,相比于原始YOLOv7算法提高25.9%,每秒传输帧数FPS相比于原算法提高4.6%。最后,将YOLOv7—AFPN—EMA的病虫害识别模型部署到Jetson Orin Nano上进行验证性检测试验,对比模型改进前后的检测精度。验证结果表明,改进算法相比于原始算法,在线实时检测精度提升11.3%,病虫害检测成功率达89.7%。 展开更多
关键词 植保无人机 喷洒系统 改进YOLOv7 病虫害
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白藜芦醇洗脱支架的理化特性和体外生物学效应
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作者 李可韵 杨玉琪 +1 位作者 费莹莹 黄帅 《中国组织工程研究》 北大核心 2026年第20期5243-5256,共14页
背景:传统药物洗脱支架虽然已成为冠状动脉粥样硬化性心脏病介入治疗的主流选择,但仍存内皮修复延迟、晚期血栓风险及慢性炎症反应等问题,因此,开发具有选择性细胞调控功能和可降解载体的新型药物洗脱支架已成为当前研究的迫切需求。目... 背景:传统药物洗脱支架虽然已成为冠状动脉粥样硬化性心脏病介入治疗的主流选择,但仍存内皮修复延迟、晚期血栓风险及慢性炎症反应等问题,因此,开发具有选择性细胞调控功能和可降解载体的新型药物洗脱支架已成为当前研究的迫切需求。目的:制备负载白藜芦醇洗脱涂层的316L不锈钢支架,系统研究该涂层的理化性能、生物相容性以及对动脉粥样硬化病灶的治疗效果。方法:①配置白藜芦醇与聚乳酸-羟基乙酸共聚物质量比分别为0%,10%,20%,30%,40%的溶液,采用蒸发沉积法在316L不锈钢片材表面制备质量分数0%,10%,20%,30%,40%白藜芦醇洗脱涂层,表征5组涂层的水接触角、血液相容性、抗氧化特性以及对人脐静脉内皮细胞、人主动脉平滑肌细胞与巨噬细胞生长行为的影响,表征质量分数30%白藜芦醇洗脱涂层的药物释放动力学与机械性能;将巨噬细胞分别接种于316L不锈钢片材、负载聚乳酸-羟基乙酸共聚物涂层316L不锈钢片材与负载质量分数30%白藜芦醇洗脱涂层316L不锈钢片材表面,加入脂多糖刺激因子建立动脉粥样硬化模型,免疫荧光染色检测CD206(抗炎型巨噬细胞)、CD86(促炎型巨噬细胞)表达。②配置白藜芦醇与聚乳酸-羟基乙酸共聚物质量比分别为0%,30%的溶液作为喷涂液,采用超声雾化喷涂法在316L不锈钢支架表面制备质量分数0%,30%白藜芦醇洗脱涂层,通过球囊扩张实验评估涂层的机械性能。结果与结论:①负载涂层316L不锈钢片材表面的水接触角均大于316L不锈钢片材,并且随着涂层中白藜芦醇质量分数的增加,不锈钢片材表面的水接触角呈降低趋势。316L不锈钢片材与负载涂层316L不锈钢片材均具有较低的溶血率(溶血率<5%);体外血小板黏附与激活实验显示白藜芦醇洗脱涂层有效抑制了血小板的附着与活化,其中质量分数30%,40%白藜芦醇洗脱涂层的作用更显著。白藜芦醇洗脱涂层可抑制巨噬细胞的活性氧释放,发挥抗氧化特性。白藜芦醇洗脱涂层可促进人脐静脉内皮细胞的增殖、抑制人主动脉平滑肌细胞与巨噬细胞的增殖,其中质量分数30%,40%白藜芦醇洗脱涂层的作用更显著。因此,后续实验选择质量分数30%白藜芦醇洗脱涂层。白藜芦醇洗脱涂层能够实现至少30d的稳定可控药物释放。免疫荧光染色显示白藜芦醇洗脱涂层能够促进巨噬细胞向抗炎表型转化。②经球囊扩张后,不锈钢支架表面的白藜芦醇洗脱涂层未出现剥落、裂缝扩展等问题,具有良好的机械性能。 展开更多
关键词 白藜芦醇 洗脱支架 超声雾化喷涂 动脉粥样硬化 生物相容性 血液相容性 抗血栓 药物释放
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