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Interfacial engineering of Al-NH_(4)CoF_(3)@P(VDF-HFP)core-shell energetic composites via electrostatic spraying:Enhanced stability and combustion performance
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作者 Xiandie Zhang Zhijie Fan +4 位作者 Heng Xu Jinbin Zou Chongqing Deng Xiang Zhou Xiaode Guo 《Defence Technology(防务技术)》 2026年第1期210-223,共14页
Al/NH_(4)CoF_(3)-Φ(Φ=0.5,1.0,1.5,2.0,and 3.0)binary composites and Al-NH_(4)CoF_(3)@P(VDF-HFP)ternary composites are fabricated via ultrasonication-assisted blending and electrostatic spraying.The effect of equivale... Al/NH_(4)CoF_(3)-Φ(Φ=0.5,1.0,1.5,2.0,and 3.0)binary composites and Al-NH_(4)CoF_(3)@P(VDF-HFP)ternary composites are fabricated via ultrasonication-assisted blending and electrostatic spraying.The effect of equivalence ratio(Φ)on the reaction properties is systematically investigated in the binary Al/NH_(4)CoF_(3)system.For ternary systems,electrostatic spraying allows both components to be efficiently encapsulated by P(VDF-HFP)and to achieve structural stabilization and enhanced reactivity through synergistic interfacial interactions.Morphological analysis using SEM/TEM revealed that P(VDF-HFP)formed a protective layer on Al and NH_(4)CoF_(3)particles,improving dispersion,hydrophobicity(water contact angle increased by 80.5%compared to physically mixed composites),and corrosion resistance.Thermal decomposition of NH_(4)CoF_(3)occurred at 265℃,releasing NH_(3)and HF,which triggered exothermic reactions with Al.The ternary composites exhibited a narrowed main reaction temperature range and concentrated heat release,attributed to improved interfacial contact and polymer decomposition.Combustion tests demonstrated that Al-NH_(4)CoF_(3)@P(VDF-HFP)achieved self-sustaining combustion.In addition,a simple validation was done by replacing the Al component in the aluminium-containing propellant,demonstrating its potential application in the propellant field.This work establishes a novel strategy for designing stable,high-energy composites with potential applications in advanced propulsion systems. 展开更多
关键词 Anti-aging properties Low-temperature reaction Electrostatic spraying Gas generation Combustion performance
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Water Quality Assessment of the Owena Multi-Purpose Dam, Ondo State, Southwestern Nigeria 被引量:2
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作者 Oyhakilome Gloria Irenosen Aiyesanmi Ademola Festus Akharaiyi Fred Coolborn 《Journal of Environmental Protection》 2012年第1期14-25,共12页
Composite water samples taken from Owena Multi-purpose Dam in six sampling campaigns covering the wet and dry seasons were analyzed for physico-chemical and microbial characteristics using standard methods for the exa... Composite water samples taken from Owena Multi-purpose Dam in six sampling campaigns covering the wet and dry seasons were analyzed for physico-chemical and microbial characteristics using standard methods for the examination of water and wastewater jointly published by the American Public Health Association, American Water Works Association and Water Pollution Control Federation. Results showed significant (p < 0.05) seasonal variations in most measured parameters with few showing significant spatial variation. The characteristics of the water from the dam lake revealed an acceptable quality for most measured parameters with low chemical pollutants burden when compared with drinking water standards and water quality for aquaculture. However, high values of turbidity, colour, iron, manganese and microbial load were recorded compared with drinking water standards, which call for proper treatment of the water before distribution for public consumption. 展开更多
关键词 Water PHYSICOCHEMICAL Characteristics Microbiology HEAVY Metals Owena multi-purpose DAM
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Using Stochastic Colored Petri nets for Designing Multi-Purpose Plants 被引量:2
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作者 Hasan Hosseini-Nasab Ali Sadri 《Engineering(科研)》 2012年第10期655-661,共7页
Designing of a multi-purpose plant as one of the well-known manufacturing systems is more challenging than other manufacturing systems. This paper applies a stochastic colored Petri net (CPN) to design and analyze mul... Designing of a multi-purpose plant as one of the well-known manufacturing systems is more challenging than other manufacturing systems. This paper applies a stochastic colored Petri net (CPN) to design and analyze multi-purpose plants. A simple approach is proposed to determine the utilization of shared resources and to reduce the equipment’s idle times. Three scenarios are presented to describe the proposed model. Generally, according to desire of a decision maker, different scenarios can be considered in the model to achieve to the expected design or plant configuration. The main characteristics of the proposed model are flexibility, the easiness of practical application and the simulation of the model in an easy way. 展开更多
关键词 multi-purpose Plant STOCHASTIC COLORED PETRI Net Simulation
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Bias Effects on the Reynolds Stress Using the Multi-Purpose Probe in IR-T1 Tokamak
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作者 M.Lafouti M.Ghoranneviss 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第1期88-91,共4页
The effect of the positive bias on Reynolds stress (RS) and its effect on the radial turbulent transport at the edge plasma (r/a =0.9) and scrape-off layer (SOL) region of plasma in tokamak are investigated. The... The effect of the positive bias on Reynolds stress (RS) and its effect on the radial turbulent transport at the edge plasma (r/a =0.9) and scrape-off layer (SOL) region of plasma in tokamak are investigated. The radial and poloidal electric fields (Sr, Ep) and ion saturation current (Is) are measured by multi-purpose probe (MPP). This probe is fabricated and constructed for the first time in the IR-T1 tokamak. The most advantage of this probe is that the variations of Er and Ep can be measured in different radii at the single shot. Thus the information of different radii can be compared with high precision. The bias voltage is fixed at Vbias = 200 V and it has been applied with the limiter bias that is fixed in r/a = 0.9. Moreover, the phase difference between radial and poloidal electric fields, and temporal evolution of the RS .spectrum detected by MPP are calculated. RS magnitude on the edge (r/a = 0.9) is more than its value in the SOL (r/a = 1.02). With the applied bias 200 V, ItS and the magnitude of the phase difference between Er and Ep are increased, while the radial turbulent transport is decreased simultaneously. Thus it can be concluded that RS affects radial turbulence. Temporal evolution of the RS spectrum shows that the frequency of RS is increased and reaches its highest value at r/a=0.9 in the presence of bias. 展开更多
关键词 of is RS been in Bias Effects on the Reynolds Stress Using the multi-purpose Probe in IR-T1 Tokamak on IR
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Kill probability modeling of multi-purpose guided missile against gunship and its application
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作者 DU Zheng CHEN Wan-chun 《Journal of Measurement Science and Instrumentation》 CAS 2014年第2期9-18,共10页
Aimed at current deficiencies of multi-purpose guided missile kill probability model against gunship, the concept of the important coefficient of vulnerability blade unit is proposed in this paper. Laser fuze actuatio... Aimed at current deficiencies of multi-purpose guided missile kill probability model against gunship, the concept of the important coefficient of vulnerability blade unit is proposed in this paper. Laser fuze actuation model and warhead condition kill probability model of rotor blades are established by Monte Carlo method and kinetics theory with new ideas. Based on limited data, armor thickness of gunship is estimated, and a complete multi-purpose guided missile kill probability mathematical model is established, which provides necessary mathematical tool for the accurate and objective analysis of multi-purpose guided missile kill probability against gunship. Based on the establishment of the model, sensitivity analysis and optimal design of the main factors of multi-purpose guided missile kill probability are conducted, and the results show that the single multi-purpose guided missile lethality performance can be improved significantly by sensitivity analysis and optimization. 展开更多
关键词 multi-purpose guided missile gunship rotor blade the important coefficient of vulnerability blade unit armorthickness kill probability
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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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基于深度学习的设施蔬菜精准施药装置设计与试验
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作者 缪宏 周涛 戴敏 《中国农机化学报》 北大核心 2026年第4期102-107,共6页
我国是设施蔬菜生产和消费大国,但是,当前的施药作业依旧主要为人工连续施药,存在设备适配性差、农药浪费率高的问题。为解决这些问题,针对设施蔬菜环境设计基于深度学习的精准施药装置。首先,进行田间参数调研,并以此建立施药机架模型... 我国是设施蔬菜生产和消费大国,但是,当前的施药作业依旧主要为人工连续施药,存在设备适配性差、农药浪费率高的问题。为解决这些问题,针对设施蔬菜环境设计基于深度学习的精准施药装置。首先,进行田间参数调研,并以此建立施药机架模型。通过仿真分析,验证施药装置结构的可靠性和稳定性。其次,针对精准施药的实时性要求和复杂的田间环境背景,对YOLOv5目标检测算法进行改进。将原有的C3模块替换成FasterNet模块,减少浮点运算量和内存访问次数。将头部网络的Conv模块替换成GSConv,进一步减少计算资源的消耗。将头部网络中的Upsample模块替换成超轻量化的上采样模块DySample,确保信息有效传递。经过消融和对比试验,验证检测模型的高效性。再次,在施药系统设计方面,完成整体系统设计,并将从目标检测算法得到的像素坐标转换为三维坐标。最后,通过设计正交试验优化施药参数。当施药高度设定为419 mm、电磁阀占空比为91%、行驶速度为0.32 m/s时,雾滴沉积的变异系数降至最低,为12.5%。此外,评估在精准施药模式下的农药节约率。结果表明,作物株距越大,精准施药时农药节约率越高。 展开更多
关键词 设施蔬菜 施药装置 深度学习 施药系统 精准施药
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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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影响冷喷涂粒子沉积的关键因素:粉末表面氧化综述
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作者 李文亚 杨景文 +2 位作者 雒晓涛 殷硕 徐雅欣 《金属学报》 北大核心 2026年第1期17-28,共12页
冷喷涂技术因具有低温固态沉积特性,在高性能金属或金属基复合涂层制备、修复及增材制造领域已有重要应用。然而,原始喷涂粉末的表面氧化状态对冷喷涂粒子沉积过程及所制备涂层或沉积体的微观组织、界面结合质量和力学性能具有重要影响... 冷喷涂技术因具有低温固态沉积特性,在高性能金属或金属基复合涂层制备、修复及增材制造领域已有重要应用。然而,原始喷涂粉末的表面氧化状态对冷喷涂粒子沉积过程及所制备涂层或沉积体的微观组织、界面结合质量和力学性能具有重要影响。一般来说,粒子表面氧化膜的存在增加了粉末的临界沉积速率,降低了粒子塑性变形能力,并在界面处形成未结合区或脆性夹杂,从而显著影响粉末的沉积效率和沉积体的力学性能。然而,在特定条件下,粉末表面的氧化膜经过碰撞作用而破碎,不连续的氧化膜均匀分布在涂层中,通过弥散强化能够提高涂层的硬度。本文主要综述了粉末表面氧化膜在喷涂沉积过程中的破碎行为及其对涂层微观组织和性能的影响,重点探讨了氧化膜对界面结合、涂层组织及性能的影响机制。此外,本文还提出了高强塑性沉积体对粉末低O含量的严格要求,为优化冷喷涂材料性能提供理论指导。最后,对粉末表面氧化膜在冷喷涂增材制造中的影响及未来研究方向进行了展望。 展开更多
关键词 冷喷涂 冷喷涂增材制造 氧化膜 O含量 粒子变形 界面结合
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不同蛋白及其添加量对喷雾干燥香菇多糖粉末特性的影响
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作者 王岸娜 王慧 +1 位作者 马琳肸 朱俊友 《中国调味品》 北大核心 2026年第3期228-233,共6页
香菇多糖是一种从香菇中提取的具有多种功能的生物活性成分。喷雾干燥香菇多糖粉末极易吸潮,吸湿性大,流动性小。为改善喷雾干燥香菇多糖粉末的性能,添加不同浓度的酪蛋白酸钠、乳清分离蛋白和大豆分离蛋白,采用喷雾干燥制取香菇多糖粉... 香菇多糖是一种从香菇中提取的具有多种功能的生物活性成分。喷雾干燥香菇多糖粉末极易吸潮,吸湿性大,流动性小。为改善喷雾干燥香菇多糖粉末的性能,添加不同浓度的酪蛋白酸钠、乳清分离蛋白和大豆分离蛋白,采用喷雾干燥制取香菇多糖粉末。喷雾干燥进口温度为170℃,风机风量为90 m^(3)/h,进料量为200 mL/h,喷嘴孔径为1 mm。结果表明,以上3种蛋白都可以有效提高香菇多糖粉末的得率,降低粉末的休止角、压缩度和含水量,减弱香菇多糖粉末的吸湿性,但粉末的溶解度减小(>90%),酪蛋白酸钠与乳清分离蛋白效果显著优于大豆分离蛋白。综合分析,添加10%的乳清蛋白效果最佳,与不添加蛋白质的香菇多糖粉末相比,得率提高了18%,休止角减小了30%,压缩度降低了11%,水分含量减小了32%,吸湿率减小了15%。 展开更多
关键词 香菇多糖 蛋白质 喷雾干燥 粉末特性
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固定式管道高压喷雾系统雾滴在荔枝冠层的沉积分布
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作者 潘波 王冰洁 +4 位作者 刘丹 耿紫琼 李松刚 林勇 姜蕾 《中国南方果树》 北大核心 2026年第1期193-198,共6页
为了探究固定式管道高压喷雾系统雾滴在荔枝树冠层的沉积分布,设置施药压力8、9、10 Mpa,施药时长30、60、90s,向上向下安装喷头,环境温湿度和风速对雾滴分布效果的影响。结果表明,压力8MPa,喷雾时长60s,喷头向下安装时雾滴的沉积分布... 为了探究固定式管道高压喷雾系统雾滴在荔枝树冠层的沉积分布,设置施药压力8、9、10 Mpa,施药时长30、60、90s,向上向下安装喷头,环境温湿度和风速对雾滴分布效果的影响。结果表明,压力8MPa,喷雾时长60s,喷头向下安装时雾滴的沉积分布效果最好。固定式管道高压喷雾系统雾滴体积中值直径(VMD)60μm左右,易受环境因素影响而发生蒸发和飘移。当环境温度39.0℃、湿度45%时叶片正面雾滴密度较温度31.8℃和湿度68%时下降55.66%~68.61%,叶片背面雾滴密度下降28.37%~71.75%。说明环境温湿度和风速可能会对雾滴沉积产生影响,在高温低湿有风的环境条件下应谨慎使用固定式管道高压喷雾系统。 展开更多
关键词 荔枝 固定式树冠管道高压喷雾系统 冠层 雾滴 沉积分布
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喷射成形多喷嘴扫描沉积界面行为模型与智能调控方法
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作者 冷晟 黄海泽 +2 位作者 蒋增华 鹿华锐 马万太 《华南理工大学学报(自然科学版)》 北大核心 2026年第1期124-133,共10页
轻质高性能铝合金材料对航空航天装备轻量化具有重要意义,由此喷射成形快速凝固技术在高强铝合金制备方面的应用受到了越来越多的关注。为满足航空航天大尺寸构件的研制需求,需要采用多喷嘴协同工作方式以获得更大的锭坯直径。多个喷嘴... 轻质高性能铝合金材料对航空航天装备轻量化具有重要意义,由此喷射成形快速凝固技术在高强铝合金制备方面的应用受到了越来越多的关注。为满足航空航天大尺寸构件的研制需求,需要采用多喷嘴协同工作方式以获得更大的锭坯直径。多个喷嘴形成了多个雾化锥,以一定的倾角在沉积界面进行扫描。在此过程中,确保熔体物质分布均匀,以及锭坯顶部沉积界面平整且稳定生长,是获得高质量、组织致密均匀的沉积坯的关键。沉积过程中多喷嘴的相关工艺参数直接影响雾化熔滴在界面上的扫描轨迹与物质沉积状态,对锭坯生长起到决定性作用。因此,以形成形貌一致、沉积质量均匀的大规格锭坯为目标,基于微尺度扫描沉积高度,考虑多喷嘴雾化锥扫描过程中出现沉积区域交叉重叠的问题,建立多喷嘴沉积界面行为模型(DSBM模型)。选择喷嘴初始倾角、喷嘴偏心距、熔体质量流率为可调整参数,根据实际工况建立约束,形成基于DSBM的参数调控方法。以锭坯沉积面不平整度的高度差H为优化目标,利用沉积界面GA-DSBM智能调控方法对沉积过程中的相关工艺参数进行仿真计算与优化。通过4喷嘴喷射成形试验对寻优得到的工艺参数进行了验证,试验所得到的直径600 mm锭坯的表面不平整高度差为7.52 mm,符合工艺设计要求,同时锭坯顶部不平整度大大降低,沉积界面物质均匀性得到改善,有效降低了锭坯孔隙率。试验过程验证了智能调控与优化方法的可行性。 展开更多
关键词 喷射成形 多喷嘴 沉积界面 沉积均匀
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桦褐孔菌生物菌液不同施肥方式对水稻生长及产量的影响
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作者 韩增华 王玉霞 +1 位作者 姜威 王笑庸 《北方水稻》 2026年第2期56-59,67,共5页
通过应用提取液、发酵液在水稻田间分蘖期、孕穗期两个不同生长期的喷施及冲施,研究桦褐孔菌液对水稻生长及产量的影响,明确其在水稻上喷施、冲施的安全浓度及应用效果。结果显示:喷施、冲施两种生物菌液均能够促进水稻生长,提高水稻产... 通过应用提取液、发酵液在水稻田间分蘖期、孕穗期两个不同生长期的喷施及冲施,研究桦褐孔菌液对水稻生长及产量的影响,明确其在水稻上喷施、冲施的安全浓度及应用效果。结果显示:喷施、冲施两种生物菌液均能够促进水稻生长,提高水稻产量,但冲施的增产幅度好于喷施。喷施量为50~200 ml/667 m^(2)时,各处理均表现为增产,叶片未出现肥害现象,水稻增产幅度为1.07%~4.26%。冲施1号、2号生物菌液的水稻分别增产了10.62%和12.45%。 展开更多
关键词 桦褐孔菌 提取液 发酵液 喷施 冲施
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基于WEED-YOLOv10的玉米杂草检测方法与对靶喷药系统设计
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作者 赵建国 安美林 +5 位作者 赵学观 王雅雅 马志凯 李媛普 王博奥 郝建军 《农业工程学报》 北大核心 2026年第1期48-57,共10页
针对玉米杂草识别过程中因光照变化导致识别精确度低及漏检问题,该研究以幼苗期玉米及其伴生杂草为研究对象,设计一种基于WEED-YOLOv10的玉米杂草检测方法。首先,通过无人机快速采集田间高分辨率图像构建了玉米杂草数据集;其次,以YOLOv... 针对玉米杂草识别过程中因光照变化导致识别精确度低及漏检问题,该研究以幼苗期玉米及其伴生杂草为研究对象,设计一种基于WEED-YOLOv10的玉米杂草检测方法。首先,通过无人机快速采集田间高分辨率图像构建了玉米杂草数据集;其次,以YOLOv10n为基线网络,将骨干网络替换为ConvNeXtV2以增强特征提取能力;继而,为避免因模块拼接可能带来的信息冗余或丢失问题提升对光照干扰的鲁棒性,嵌入CBAM注意力机制;然后,引入SlimNeck结构优化网络计算效率,有效平衡了模型计算资源消耗与特征表征能力;最后,使用Focaler-EIoU损失函数进一步提高模型定位精度。试验结果表明,WEED-YOLOv10在精确率、召回率、mAP@50、mAP@50:95和F1分数上分别达到85.4%、88.1%、90.9%、48.5%和86.7%,较基准模型分别提升了2.4、2.9、3.5、7.0、2.6个百分点,各项精度指标均优于其他对比模型,部署在NVIDIA Jetson orin NX上的图片推理速度达到28.7帧/s,实现了检测速度与精度的平衡。进一步地,基于WEED-YOLOv10开发对靶喷药系统,该系统实时捕捉并解析来自模型的识别信号,实现对除草喷施装置的精准调控。田间试验结果显示,对靶喷药系统施药准确率为93.7%,喷洒覆盖率为90.5%,对靶偏差为1.45cm,杂草实时检测速度为20.1帧/s,实现了自动化的玉米田间除草作业。该研究为复杂光照场景下农田杂草治理提供了可靠的技术方案,对推动农业智能化作业具有重要意义。 展开更多
关键词 杂草识别 YOLOv10n 特征提取 注意力机制 SlimNeck 对靶喷药系统
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融合树干特征与回环优化的果园喷雾机器人同步定位与建图方法
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作者 刘慧 黄宇轩 +2 位作者 沈跃 沈亚运 吴瑞泽 《农业工程学报》 北大核心 2026年第3期46-55,共10页
针对复杂果园环境下实时动态差分(real-time kinematic,RTK)信号易丢失以及传统激光同步定位与建图(simultaneous localization and mapping,SLAM)方法在复杂果园中因几何特征离散不稳定及局部环境相似度高导致的定位精度偏低的问题,该... 针对复杂果园环境下实时动态差分(real-time kinematic,RTK)信号易丢失以及传统激光同步定位与建图(simultaneous localization and mapping,SLAM)方法在复杂果园中因几何特征离散不稳定及局部环境相似度高导致的定位精度偏低的问题,该研究提出了一种融合树干几何特征与改进回环描述子的果园喷雾机器人高精度激光惯性定位与建图方法。该方法引入树干几何特征提取算法,利用树干表面的高稳定性构建高置信度的点面约束,强化前端配准精度;后端利用果园树木空间分布特征,设计基于树干拓扑结构的回环描述子与双重判别机制,有效检测回环并消除累积误差。在BotanicGarden公有数据集和自制苗圃.数据集上的试验表明,该方法在复杂果园场景下的定位精度较FAST-LIO2和SC-LIO-SAM分别提升约42.4%和48.3%,可为果园喷雾机器人高精度自主作业提供可靠的定位支持。 展开更多
关键词 机器人 喷雾 果园 树干特征 SLAM 回环检测 精准定位
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叶面喷施碳量子点对玉米生长、产量及品质的影响
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作者 郑国保 李苗 +2 位作者 黄慧 康振辉 朱金霞 《农业科学研究(中英文)》 2026年第1期83-89,共7页
研究叶面喷施不同浓度碳量子点(CDs)对玉米生长、产量和品质的影响,明确叶面喷施CDs的适宜浓度。采用单因素随机区组试验设计,于玉米6叶期、大喇叭口期和吐丝期喷施浓度(w)分别为0(Y_(CK))、5.00%(Y_(C1))、10.00%(Y_(C2))、20.00%(Y_(C... 研究叶面喷施不同浓度碳量子点(CDs)对玉米生长、产量和品质的影响,明确叶面喷施CDs的适宜浓度。采用单因素随机区组试验设计,于玉米6叶期、大喇叭口期和吐丝期喷施浓度(w)分别为0(Y_(CK))、5.00%(Y_(C1))、10.00%(Y_(C2))、20.00%(Y_(C3))和40.00%(Y_(C4))的CDs。结果表明:前期喷施CDs对玉米生长的影响不明显,随着喷施次数增加可明显增加茎直径和干物质的积累量;Y_(C3)处理的叶绿素SPAD值、光合速率、蒸腾速率、气孔导度和胞间CO_(2)浓度与Y_(CK)的差异显著,在灌浆始期较Y_(CK)增加8.38%、801.15%、210.34%、254.13%和198.50%,在乳熟期较Y_(CK)增加6.36%、261.60%、103.33%、126.73%和185.09%;收获后Y_(C3)的穗行数、行粒数、百粒质量和产量较Y_(CK)增加4.81%、4.10%、5.21%和9.98%,籽粒粗蛋白质和粗脂肪含量较Y_(CK)增加6.54%和14.71%。因此,叶面喷施w(CDs)为20.00%时,能够增强玉米叶片光合能力,促进光合作用,对玉米产量和品质的提升具有明显的促进作用。 展开更多
关键词 叶面喷施 碳量子点 玉米 产量 品质
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过氧化氢气溶胶喷雾法对物体表面的消毒效果观察
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作者 刘天 朱佩峰 +4 位作者 任志华 王玉峰 纪雪可 田靓 潘引君 《中国消毒学杂志》 2026年第1期22-23,29,共3页
目的观察过氧化氢气溶胶喷雾法对物体表面的消毒效果。方法采用模拟现场和现场消毒试验法,对过氧化氢气溶胶喷雾法消毒物体表面的效果进行观察和评价。结果采用自然菌法评价非织物型物体表面时能够达到消毒效果,评价织物型物体表面时无... 目的观察过氧化氢气溶胶喷雾法对物体表面的消毒效果。方法采用模拟现场和现场消毒试验法,对过氧化氢气溶胶喷雾法消毒物体表面的效果进行观察和评价。结果采用自然菌法评价非织物型物体表面时能够达到消毒效果,评价织物型物体表面时无法达到消毒效果;采用指示菌片消毒法评价空间消毒对物体表面的消毒效果时无法达到消毒效果。结论本实验条件下,使用10~30 g/L过氧化氢气溶胶喷雾进行空间消毒无法确保物体表面达到消毒效果。 展开更多
关键词 过氧化氢 气溶胶喷雾 空间消毒 消毒效果
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