PEST MANAGEMENT SCIENCE
·
2021
·Vol. 78
·期 1
·43-51
·
IF 4.845
Xiaojing Yan,Huizhu Yuan,Yixuan Chen,Xin Shi,Xiaohui Liu,Zhenying Wang,Yue Liu,Daibin Yang
BACKGROUND The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), is an invasive pest. Maize is one of its preferred host plants. The traditional application of granules has been effective for the control of FAW. Nevertheless, the challenge is to develop an application method that is less labor-intensive and also efficient. RESULTS Tiny granules in the size range of 0.38–0.55 mm were prepared by the centrifugal granulation method for drone application. The in-swath distribution patterns of granules deposited on sticky tapes were similar to the distribution of aqueous droplets through drone spraying. In the range of 1.5–3.5 m, a relatively higher aircraft height of flight can provide a more uniform distribution pattern of deposited granules, but resulted in less deposit of tiny granules in the whorl of maize plants. Similarly, the deposit of granules in the whorl of maize plants significantly decreased when the flight speed increased from 4 to 6 m s −1 . Granules gathered in the whorl accounted for 50.8–58.7% of total granules deposited in the maize canopy. The field experiment demonstrates granular formulations (containing 0.25% chlorantraniliprole + 0.15% emamectin benzoate, or higher concentrations) can provide better and longer duration of FAW control than the aqueous spray formulation at the whorl stage of maize plants. CONCLUSION Broadcasting of tiny granules by drone can provide better FAW control than liquid spray. The architecture of the maize plant and the downward airstream of the drone create favorable conditions for the deposition of granules in whorls. © 2021 Society of Chemical Industry.
研究领域:
农业昆虫学
·
害虫防治
✓ 已验证
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2018
·
IF 5.123
Hao Sun,Yuan Jia,Hui Dong,Longxiang Fan,Jianping Zheng
On-site spatial variation study of airborne trace metals has been known to be the key to providing a comprehensive evaluation of air pollution information at any targeted location. However, the existing portable approaches either do not allow sample analysis in the longitudinal direction or is not yet practically applicable due to due to the lack of a portable detection method. In this paper, by integrating paper based colorimetric detection via cellphone and unmanned aerial vehicle (UAV) in-air sampling, we present an approach for on-site multiaxial quantification of airborne trace metals in an arrayed format. Using a self-built sampler mounting on a UAV, our approach enables automatic, multiaxial air PM sampling. In addition, by relying only on a cellphone and a custom-made field reaction kit, samples collected in-air can be readily processed, detected in an arrayed format and interpreted on-site within 30 min. Finally, an ultrafast batch-to-batch paper microfluidic chip fabrication protocol enables 48 chips to be fabricated under 30 s at a cost of 1.92 $, making the approach well-suited for disposable on-site use. Our system was first calibrated for 6 metals commonly found in airborne PM (i.e. Co, Cu, Fe, Mn, Cr and Ni), and the corresponding metals detection limits were found to be 8.16, 45.84, 1.86 × 10 2 , 10.08, 1.52 × 10 2 and 80.40 ng. The validity of our approach was then demonstrated by characterizing 6 metals commonly found in air PM using a certified ash sample, and the experimentally determined metal weight percentage showed a good agreement with the manufacture certified value. Finally, the approach was used for on-site airborne trace metals spatial variation study at 4 difference locations in Fuzhou City (China), thus demonstrating the significance of our approach in supplementing air pollution information gathering and progressing rapid, on-site air toxicity assessment research.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Plant Science
·
2022
·
IF 6.627
Li Longlong,Hu Zhihong,Liu Qingju,Yi Tongchuan,Han Ping,Zhang Ruirui,Pan Ligang
Extensive research has been conducted on plant protection unmanned aerial vehicle (UAV) chemical application technology in recent years owing to its importance as a means of pest and disease control. UAV spraying in orchards faces the drawback of drift risk and can be hazardous to non-targeted crops, humans, and the environment. A detailed and systematic analysis must be performed to determine the uniformity and drift risk of plant UAV sprays. In this study, a peach orchard is sprayed with a plant-protection UAV at three different flight velocities and we evaluate the combined pesticide deposition performance of the canopy, ground loss, downwind ground drift, and airborne drift. Additionally, the droplet size and coverage rate in the canopy are calculated by using water-sensitive paper. The results demonstrate that there is significant difference in the droplet size at flight velocities of 1–3 m/s. The droplet size in the lower canopy is slightly smaller than those in the middle and upper parts. Increasing the flight velocity helps the pesticide droplets to spread and penetrate the canopy. However, it also causes a non-uniform pesticide deposition, reduced effective coverage ratio and effective density ratio. Among the three pesticides used in the experiment, imidacloprid exhibits the best deposition efficiency. The deposition amount and normalized deposition amount in the canopy were the highest at a flight velocity of 2 m/s, accompanied by a lower ground loss under the canopy. The highest near-field ground drift is observed at a velocity of 1 m/s, and the far-field airborne drift is highest at 3 m/s. Lastly, this study provides a reference for the commercial application of plant-protection UAVs.
研究领域:
农业科学
·
植物保护
✓ 已验证
DOI
PubMed
高影响因子
Applied Sciences-Basel
·
2021
·Vol. 11
·期 16
·7258
·
IF 2.679
Qi Liu,Shengde Chen,Guobin Wang,Yubin Lan
Background: Unmanned Aerial Vehicles (UAVs) applied to agricultural plant protection is widely used, and the field of operation is expanding due to their high efficiency and pesticide application reduction. However, the work on pesticide drift lags behind the development of the UAV spraying device. Methods: We compared the spray drift potential at four liquid pressures of 2, 3, 4, and 5 bar ejected from the hydraulic nozzles mounted on a UAV test platform exposed to different wind speeds of 2, 4, and 6 m/s produced by a wind tunnel. The combination of the wind tunnel and the UAV test platform was used to obtain strict test conditions. The droplet size distribution under spray drift pressures was measured by a laser diffraction instrument. Results: Increasing the pressure leads to smaller droplet volume diameters and produced fine droplets of less than 100 µm. The deposition in the drift area was elevated at most of the sampling locations by setting higher pressure and faster wind speed. The deposition ratios were all higher than the flow ratios under three wind speeds after the adjustment of pressures. For most samples within a short drift distance (2–8 m), the drift with the rotor motor off was more than an order of magnitude higher than that with the rotor motor on at a pressure of 3 bar. Conclusions: In this study, the wind speed and liquid pressure all had a significant effect on the UAV spray drift, and the rotor wind significantly inhibited a large number of droplets from drifting further.Keywords:unmanned aerial vehicle;liquid pressure;drift deposition;wind speed;rotor wind field;droplet size
研究领域:
农业工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2023
·Vol. 19
·期 36
·2300286
·
IF 13.3
Jianpeng Liu,Chang Cheng,Tianle Wang,Juncheng Zhu,Zhong Li,Guang Ao,Wenliang Zhu,Giuseppe Pezzotti,Jiliang Zhu
Lithium–sulfur (Li–S) battery has been considered as a strong contender for commercial aerospace battery, but the commercialization requires Ah-level pouch cells with both efficient discharge at high rates and ultra-high energy density. In this paper, the application of lithium–sulfur batteries for powering drones by using the cathode of highly dispersed sulfur nanoparticles with well-controlled particle sizes have been realized. The sulfur nanoparticles are prepared by a precipitation method in an eco-friendly and efficient way, and loaded on graphene oxide-cetyltrimethylammonium bromide by molecular grafting to realize a large-scale fabrication of sulfur-based cathodes with superior electrochemical performance. A button cell based on the cathode exhibits an excellent discharge capacity of 62.8 mAh cm −2 at a high sulfur loading of 60 mg cm −2 (i.e., 1046.7 mAh g −1 ). The assembled miniature pouch cell (PCmini) shows a discharge capacity of 130 mAh g −1 , while the formed Ah-level pouch cell (PCAh) achieves energy density of 307 Wh kg −1 at 0.3C and 92 Wh kg −1 at 4C. Especially, a four-axis propeller drone powered by the PC has successfully completed a long flight (>3 min) at high altitudes, demonstrating the practical applicability as aviation batteries.
研究领域:
材料科学
·
能源工程
·
航空航天工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Omega
·
2020
·
IF 2.87
Kun Wei,Weiming Xu,Qin Liu,Liyun Yang,Zhuo Chen
Traditional pesticide spraying methods such as knapsack sprayers are inefficient. Ground application equipment is restricted by the terrain and damages the crops. Pesticides cannot be sprayed over a large area in a short time; thus, when there are concentrated outbreaks of pests with strong migration capacity, such as Spodoptera frugiperda, pests could not be controlled in a small area. Therefore, it is difficult to achieve a satisfactory control effect. Plant protection unmanned aerial vehicles (UAVs) have high efficiency and spray pesticides at low altitude and can suitably prevent and control the outbreak of pests. However, pesticide formulations suitable for UAVs are rare. In this study, we developed ultralow-volume (ULV) sprays suitable for plant protection UAVs. We studied their properties and found that the ULV sprays have good wettability and can be fully spread. The minimum contact angle on corn leaves is up to 19°, and the maximum retention is 2.7 times that of the reference product. They also have superior resistance to rain washout and can effectively extend the duration and utilization of pesticides. When sprayed by plant protection UAVs, the decrease rate of the ULV spray at 3 L/ha to S. frugiperda larvae is 81.31% and the control effect is 83.01%, both higher than those of the reference product 40% chlorantraniliprole–thiamethoxam water-dispersible granules (decrease rate 67.39%, control effect 70.35%), sprayed with a knapsack sprayer.
研究领域:
农业科学
·
害虫防治
✓ 已验证
DOI
高影响因子
Nano Energy
·
2024
·
IF 16.8
He Liu,Deliang Li,Haoxiang Chu,Yong Ding,Zhiwei Fu,Xinan Yao,Jiayi Zhu,Jiaqi Yang,Ruonan Liu,Tao Xu,Simian Fu,Yiying Liu,Yixuan Han,Yanpeng Wang,Yue Zhao,Xiaoyu Cui,Ye Tian
Touch pad based on triboelectric nanogenerator are attracting attention in the field of wearable electronics and human-machine interaction. However, it is still a challenge to realize touch pads combining large-area metamorphic stretchability, high power triboelectric sensing, intelligent free-sliding recognition and availability in extreme environments. Here, we fabricate an ultra-stretchable triboelectric touch pad by integrating liquid metal and high performance hydrogel-based triboelectric sensor arrays, which achieves Transformer-assisted gesture recognition for drone flight direction control. The internal hydrogel electrode has great stretchability, electrical conductivity and anti-freeze properties. Encapsulated in Ecoflex with sandpaper micro-surfaces, it endows high triboelectric power density and pressure sensitivity. With screen-printed liquid metal, the integrated touch pad is fully ultra-stretchable and large-area strain stability. Combining Internet of Things, we build a Transformer-assisted human machine interface. Notably, slide gesture signal peak deviation is reduced by integral processing. The random free-sliding gesture signals are parsed by the Transformer algorithm with 96.83 % accuracy. Multi-threaded signal processing improves the response speed and throughput of the system. The accurate real-time gesture recognition for drone flight direction control in extreme environment is realized. This human machine interface can facilitate development of next generation intelligent remote interactive platforms.
研究领域:
可穿戴电子设备
·
人机交互
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
npj Flexible Electronics
·
2025
·Vol. 9
·期 1
·1-9
·
IF 15.5
Xu Sijia,Li Ruiqi,Tian Shu,Yu Junyu,An Chengtao,Yang Kai,Yang Jing,Zhang Lei
In-flight icing is a common hazard in unmanned aerial vehicles (UAVs), accounting for 25% of drone accidents due to their sensitivity to weight increase. Anti-icing technology for UAVs remains challenging because of their limited payload capacity and insufficient power to support electrothermal deicing systems. In this study, a self-healing intelligent skin was developed for small-size smart devices, such as UAVs. It provides anti-icing and icephobic capabilities in addition to real-time monitoring of in-flight icing. This skin consists of five layers, including self-healing supramolecular elastomers and electrodes, with an encapsulation layer composed of a specially designed fluoropolymer to decrease the ice nucleation temperature (−28.4 °C) and ice adhesion strength (33.0 kPa). Notably, this skin can monitor ice accretion on the UAV surface in real time, and its sensing performance undergoes complete self-recovery after damage. This study paves the way for intelligent UAVs to operate safely under extreme weather conditions.
研究领域:
航空宇航科学与技术
·
材料科学
·
智能材料
·
传感器技术
·
机器人学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2025
·
IF 5.1
Li Zeng,Yuan Li,Qichao Li,Yiping Guo
Polyvinylidene fluoride (PVDF) has attracted extensive attention for flexible piezoelectric strain sensors due to its piezoelectric activity and mechanical robustness. However, practical application in small-strain monitoring occasions remains restricted by limitations such as low intrinsic piezoelectricity. Inspired by the mechanical structure of Venus flytrap's trigger hairs, this study synergistically combines modulus differentiation mechanisms with a coaxial architecture to develop core–shell nanofibers. The fiber structure comprises a rigid Polyamide 66 (PA66) core, a flexible PVDF sensing layer as the outer shell, and polydopamine-modified BaTiO3 nanoparticles (PBTO) distributed within the outer sheath. These bioinspired fibers feature a radial stiffness-flexibility combination to achieve directional stress transmission. The modified nanofiber membrane achieves an 840% enhancement in voltage output compared to pure PVDF, demonstrating bending sensitivity of Gauge Factor (GF) 221.4 and only 0.67% signal attenuation over 12 000 cyclic tests. Leveraging this amplification mechanism, the core–shell nanofibers have been engineered into bending vector sensors capable of discerning wind velocity magnitude and directional parameters. This approach shows potential for optimizing unmanned aerial vehicle flight trajectories to enhance operational efficiency.
研究领域:
材料科学
·
纳米技术
·
传感器
·
生物力学
·
柔性电子
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2025
·
IF 26.8
Kaiyuan Zheng,Lili Wang,Xiaofan Zhang,Chunyu Zhou,Ming Yue,Xiaobiao Shan
Biomass-based triboelectric nanogenerators (TENGs) have attracted attention in the fields of biomedical and wearable electronics. This study formed three stable frictional electric films, namely chitosan quaternary ammonium salt(CQAS)/Sc 2 O 3 , CQAS/MnO 2 , and CQAS/ZnO, through electrostatic attraction between positively charged CQAS and electron-rich oxygen atoms in metal oxides. Molecular dynamics simulations show negative interfacial binding energy, indicating structural stability. Density functional theory confirms the accumulation of electrons near oxygen atoms, especially in ZnO, where the average oxygen electron is −0.89, forming a strong negative potential. The electric hysteresis loop of CQAS/ZnO exhibits the best closure, and its potential shift response is stable. The leakage current of CQAS/ZnO is the lowest, at 37.2 µA, indicating that ZnO easily forms a more stable structure with CQAS through electrostatic attraction. CQAS/ZnO exhibits the best triboelectric electrical performance, with an open circuit voltage of 1260 V and a transferred charge density of 11.50 nC cm −2 . This work proposes a theoretical model that supports the pairing of metal oxides and polymers, improving the triboelectric electrical performance and increasing the device quality factor of the TENGs from 0.26 for pure CQAS to 1.0, an increase of 3.85 times. Efficient energy conversion and human-machine interaction are achieved.
研究领域:
纳米技术
·
能源材料
·
可穿戴电子学
·
人机交互
·
计算材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Shengwen Zou,Guangxin Liu,Yi Xin,Jinlong Jin,Xiaojun Yan,Jianmei Huang
Antisolvents play a vital role in the one-step solution deposition method for fabricating efficient perovskite solar cells (PSCs). However, the widely used chlorobenzene (CB) antisolvent does not expel the residual host solvent dimethyl sulfoxide (DMSO) due to their weak interaction, leading to defects and voids in the perovskite films. Herein, ethyl acetate was strategically introduced into CB to modulate the donor number and coordination capacity of the antisolvent, enabling efficient extraction of residual DMSO and considerably reducing defects and voids in the films. Importantly, the optimized antisolvent adjusted the energy level of the perovskite films, thus reducing the energy barrier between the electron transport layer and the perovskite films. This energy-level alignment enhanced the electron extraction and suppressed nonradiative recombination. Consequently, an outstanding open-circuit voltage of 1.254 V was achieved, representing the highest reported value among the highly efficient PSCs (PCE > 23 %). The devices delivered efficiencies of 24.71 % and 20.05 % for the small-area device and module, respectively. A solar hybrid energy supply system comprising 16 interconnected modules was then successfully assembled and used to power a tilt-rotor drone, achieving a 10.45 % extension in flight time compared to the battery-only system.
研究领域:
可再生能源
·
材料科学
·
光伏技术
·
化学工程
·
航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2022
·
IF 18.027
Qingqing Cheng,Zhizhi Sheng,Yongfeng Wang,Jing Lyu,Xuetong Zhang
Aerogels represent a kind of nanoporous solid with immense importance for a plethora of diverse applications. However, on-demand conformal shaping capacity remains extremely challenging due to the strength unfavorable during aerogel processing. Herein, a universal microgel-directed suspended printing (MSP) strategy is developed for fabricating various mesoporous aerogels with spatially stereoscopic structures on-demand. As a proof-of-concept demonstration, through the rational design of the used microgel matrix and favorable printing of the Kevlar nanofiber inks, the Kevlar aerogels with arbitrary spatial structure have been fabricated, demonstrating excellent printability and programmability under a high-speed printing mode (up to 167 mm s–1). Furthermore, the custom-tailored Kevlar aerogel insulator possessing superior thermal insulation attribute has ensured normal discharge capacity of the drone even under a harsh environment (−30 °C). Finally, various types of spatial 3D aerogel architectures, including organic (cellulose, alginate, chitosan), inorganic (graphene, MXene, silica), and inorganic–organic (graphene/cellulose, MXene/alginate, silica/chitosan) hybrid aerogels, have been successfully fabricated, suggesting the universality of the MSP strategy. The strategy reported here proposes an alternative for the development of various customized aerogels and stimulates the inspiration to truly arbitrary architectures for wider applications.
研究领域:
材料科学
·
纳米技术
·
增材制造
·
热工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）