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Time and Space Efficient Multi-Model Convolution Vision Transformer for Tomato Disease Detection from Leaf Images with Varied Backgrounds
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作者 Ankita Gangwar Vijaypal Singh Dhaka +3 位作者 Geeta Rani Shrey Khandelwal Ester Zumpano Eugenio Vocaturo 《Computers, Materials & Continua》 SCIE EI 2024年第4期117-142,共26页
A consumption of 46.9 million tons of processed tomatoes was reported in 2022 which is merely 20%of the total consumption.An increase of 3.3%in consumption is predicted from 2024 to 2032.Tomatoes are also rich in iron... A consumption of 46.9 million tons of processed tomatoes was reported in 2022 which is merely 20%of the total consumption.An increase of 3.3%in consumption is predicted from 2024 to 2032.Tomatoes are also rich in iron,potassium,antioxidant lycopene,vitamins A,C and K which are important for preventing cancer,and maintaining blood pressure and glucose levels.Thus,tomatoes are globally important due to their widespread usage and nutritional value.To face the high demand for tomatoes,it is mandatory to investigate the causes of crop loss and minimize them.Diseases are one of the major causes that adversely affect crop yield and degrade the quality of the tomato fruit.This leads to financial losses and affects the livelihood of farmers.Therefore,automatic disease detection at any stage of the tomato plant is a critical issue.Deep learning models introduced in the literature show promising results,but the models are difficult to implement on handheld devices such as mobile phones due to high computational costs and a large number of parameters.Also,most of the models proposed so far work efficiently for images with plain backgrounds where a clear demarcation exists between the background and leaf region.Moreover,the existing techniques lack in recognizing multiple diseases on the same leaf.To address these concerns,we introduce a customized deep learning-based convolution vision transformer model.Themodel achieves an accuracy of 93.51%for classifying tomato leaf images with plain as well as complex backgrounds into 13 categories.It requires a space storage of merely 5.8 MB which is 98.93%,98.33%,and 92.64%less than stateof-the-art visual geometry group,vision transformers,and convolution vision transformermodels,respectively.Its training time of 44 min is 51.12%,74.12%,and 57.7%lower than the above-mentioned models.Thus,it can be deployed on(Internet of Things)IoT-enabled devices,drones,or mobile devices to assist farmers in the real-time monitoring of tomato crops.The periodicmonitoring promotes timely action to prevent the spread of diseases and reduce crop loss. 展开更多
关键词 TOMATO disease TRANSFORMER deep learning mobile devices
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煤油基Fe_3O_4磁性流体制备及表征 被引量:1
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作者 任志强 洪若瑜 +1 位作者 B. Xu 李洪钟 《化工新型材料》 CAS CSCD 北大核心 2008年第9期47-48,59,共3页
以FeCl3和FeSO4为铁源,以煤油为载液,用油酸为表面改性剂,采用一步法制备煤油基Fe3O4磁性流体。研究发现油酸可以成功地包覆在磁性颗粒表面,Fe3O4磁性颗粒平均粒径为10~20nm,晶型为反尖晶石型;磁性流体磁化率为6.53×10^-4,磁化强度... 以FeCl3和FeSO4为铁源,以煤油为载液,用油酸为表面改性剂,采用一步法制备煤油基Fe3O4磁性流体。研究发现油酸可以成功地包覆在磁性颗粒表面,Fe3O4磁性颗粒平均粒径为10~20nm,晶型为反尖晶石型;磁性流体磁化率为6.53×10^-4,磁化强度为20.9emu/g,可以长期稳定存在。 展开更多
关键词 磁性流体 纳米粒子 表面改性
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PMMA/石墨导电复合材料的制备与表征 被引量:4
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作者 黄光平 洪若瑜 +2 位作者 B.Xu 李洪钟 尉东光 《化学研究与应用》 CAS CSCD 北大核心 2008年第7期848-853,共6页
以可膨化石墨为原料,高温处理得到膨化石墨,再经过超声处理,得到纳米薄片石墨。将得到的纳米薄片石墨与甲基丙烯酸甲酯单体在超声作用下预聚,灌模,得到块状的聚甲基丙烯酸甲酯(PMMA)/石墨复合材料。用扫描电子显微镜(SEM)、透射电子显微... 以可膨化石墨为原料,高温处理得到膨化石墨,再经过超声处理,得到纳米薄片石墨。将得到的纳米薄片石墨与甲基丙烯酸甲酯单体在超声作用下预聚,灌模,得到块状的聚甲基丙烯酸甲酯(PMMA)/石墨复合材料。用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、选区电子衍射SAD、红外、热重等分析仪器表征了纳米石墨薄片及PMMA/石墨复合材料。测试了复合材料的力学、电学性能,发现在室温下该复合材料的渗滤阀值为1.3%(wt),且保证石墨含量在1.4%(wt)时,即可保证复合材料具有良好的电学和力学性能。 展开更多
关键词 石墨 插层反应 原位聚合 聚甲基丙烯酸甲酯
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Highly Ordered Thermoplastic Polyurethane/Aramid Nanofiber Conductive Foams Modulated by Kevlar Polyanion for Piezoresistive Sensing and Electromagnetic Interference Shielding 被引量:8
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作者 Kunpeng Qian Jianyu Zhou +4 位作者 Miao Miao Hongmin Wu Sineenat Thaiboonrod Jianhui Fang Xin Feng 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第6期335-352,共18页
Highly ordered and uniformly porous structure of conductive foams is a vital issue for various functional purposes such as piezoresistive sensing and electromagnetic interference(EMI) shielding. With the aids of Kevla... Highly ordered and uniformly porous structure of conductive foams is a vital issue for various functional purposes such as piezoresistive sensing and electromagnetic interference(EMI) shielding. With the aids of Kevlar polyanionic chains, thermoplastic polyurethane(TPU) foams reinforced by aramid nanofibers(ANF) with adjustable pore-size distribution were successfully obtained via a nonsolvent-induced phase separation. In this regard, the most outstanding result is the in situ formation of ANF in TPU foams after protonation of Kevlar polyanion during the NIPS process. Furthermore, in situ growth of copper nanoparticles(Cu NPs) on TPU/ANF foams was performed according to the electroless deposition by using the tiny amount of pre-blended Ti_(3)C_(2)T_(x) MXene as reducing agents. Particularly, the existence of Cu NPs layers significantly promoted the storage modulus in 2,932% increments, and the well-designed TPU/ANF/Ti_(3)C_(2)T_(x) MXene(PAM-Cu) composite foams showed distinguished compressive cycle stability. Taking virtues of the highly ordered and elastic porous architectures, the PAM-Cu foams were utilized as piezoresistive sensor exhibiting board compressive interval of 0–344.5 kPa(50% strain) with good sensitivity at 0.46 kPa^(-1). Meanwhile,the PAM-Cu foams displayed remarkable EMI shielding effectiveness at 79.09 dB in X band. This work provides an ideal strategy to fabricate highly ordered TPU foams with outstanding elastic recovery and excellent EMI shielding performance, which can be used as a promising candidate in integration of satisfactory piezoresistive sensor and EMI shielding applications for human–machine interfaces. 展开更多
关键词 Highly ordered conductive foams MXene NANOFIBER Thermoplastic Kevlar polyanion Piezoresistive sensing Electromagnetic interference shielding
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New redox-mediating polymer binder for enhancing performance of Li-S batteries 被引量:1
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作者 Soochan Kim Misuk Cho +1 位作者 Chalathorn Chanthad Youngkwan Lee 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第5期154-161,共8页
Lithium-sulfur(Li-S)batteries are promising energy storage devices owing to their high energy density and the low cost of sulfur.However,they are still far from being applied commercially because of the detrimental ca... Lithium-sulfur(Li-S)batteries are promising energy storage devices owing to their high energy density and the low cost of sulfur.However,they are still far from being applied commercially because of the detrimental capacity fade caused by the dissolution of lithium polysulfide(LPS)in liquid electrolyte.In this study,we introduced a new polymer binder having a redox-mediating function that assists in the reduction of soluble LPS to Li2S at the cathode to suppress the shuttle effect as well as enhance sulfur utilization.An amine group containing benzo(ghi)perylene imide(BPI)was synthesized and grafted onto poly(acrylic acid)to produce a redox-mediating polymer binder.An Li-S cell fabricated using the new redox-mediating polymer binder demonstrated a capacity decay retention of 0.036%per cycle up to 500 cycles at 0.5 C with a coulombic efficiency of 98%. 展开更多
关键词 Lithium-sulfur battery Redox MEDIATOR BPI BINDER CYCLIC stability
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Quantum cascade superluminescent light emitters with high power and compact structure 被引量:1
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作者 Jialin Sun Chuncai Hou +7 位作者 Hongmei Chen Jinchuan Zhang Ning Zhuo Jiqiang Ning Changcheng Zheng Zhanguo Wang Fengqi Liu Ziyang Zhang 《Journal of Semiconductors》 EI CAS CSCD 2020年第1期78-82,共5页
Quantum cascade(QC)superluminescent light emitters(SLEs)have emerged as desirable broadband mid-infrared(MIR)light sources for growing number of applications in areas like medical imaging,gas sensing and national defe... Quantum cascade(QC)superluminescent light emitters(SLEs)have emerged as desirable broadband mid-infrared(MIR)light sources for growing number of applications in areas like medical imaging,gas sensing and national defense.However,it is challenging to obtain a practical high-power device due to the very low efficiency of spontaneous emission in the intersubband transitions in QC structures.Herein a design of^5μm SLEs is demonstrated with a two-phonon resonancebased QC active structure coupled with a compact combinatorial waveguide structure which comprises a short straight part adjacent to a tilted stripe and to a J-shaped waveguide.The as-fabricated SLEs achieve a high output power of 1.8 mW,exhibiting the potential to be integrated into array devices without taking up too much chip space.These results may facilitate the realization of SLE arrays to attain larger output power and pave the pathway towards the practical applications of broadband MIR light sources. 展开更多
关键词 quantum cascade superluminescent diode mid-wave infrared
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Low and High-Loaded Electroactive Polyvinylidene Fluoride Polymers
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作者 Prissana Rakbamrung Nantakan Muensit 《材料科学与工程(中英文版)》 2010年第6期23-31,共9页
关键词 聚偏氟乙烯 电活性聚合物 高负载 聚合物复合材料 填充复合材料 表面活性剂 传感器应用 聚合物分散剂
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Silicon Nanocrystals on the Surface of Standard Si Wafers: A Micro-Raman Investigation
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作者 Mohammed S. G. Mohammed Enzo Cazzanelli +1 位作者 Angela Fasanella Marco Castriota 《Journal of Materials Science and Chemical Engineering》 2018年第7期104-116,共13页
The presence of silicon nanocrystals on the surface of standard wafer samples of Si, conserved under “usual” laboratory conditions, has been investigated by micro-Raman analysis, performed for increasing intensity o... The presence of silicon nanocrystals on the surface of standard wafer samples of Si, conserved under “usual” laboratory conditions, has been investigated by micro-Raman analysis, performed for increasing intensity of laser irradiation. The poor thermal connection of such small crystals to the Si wafer bulk allows for the appearance of two well distinct Raman bands in the spectra, with a different evolution for increasing irradiance levels: the first, expected, due to bulk silicon response, the other one assignable to the silicon nanocrystals. A careful analysis of peak position and linewidth has been carried out, both for the Raman contribution from the nanocrystals, reaching high temperatures under irradiation (up to 1400 K), and for the one from the “bulk” Si, which remains practically at room temperature. The analysis of the spectra and the comparison with previous studies on nc-Si suggest that such nanocrystals do not have a very small size, so that the observed changes of spectral parameters are mainly due to laser heating, rather than quantum confinement effects. In any case, we performed also an independent size deter-mination by AFM mapping, confirming a size distribution well peaked be-tween 50 and 100 nm. As a corollary from this analysis, we get the indication that apparent linewidths and positions, at low laser irradiation levels, can be slightly changed in the presence of nc-Si on the surface. It is due to the differ-ent thermal responses of bulk and nanocrystalline components, inducing un-resolved separate components;this hypothesis suggests reanalysing some previous experimental data, in particular for many Raman spectra of Si col-lected at “room temperature”. 展开更多
关键词 Silicon NANOCRYSTALS Laser Heating RAMAN LINEWIDTH AFM Measurement
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Synchronous deprotonation–protonation for mechanically robust chitin/aramid nanofibers conductive aerogel with excellent pressure sensing, thermal management, and electromagnetic interference shielding 被引量:3
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作者 Xinxin Zhang Kunpeng Qian +3 位作者 Jianhui Fang Sineenat Thaiboonrod Miao Miao Xin Feng 《Nano Research》 SCIE EI CSCD 2024年第3期2038-2049,共12页
Aerogels with regularly porous structure and uniformly distributed conductive networks have received extensive attention in wearable electronic sensors,electromagnetic shielding,and so on.However,the poor mechanical p... Aerogels with regularly porous structure and uniformly distributed conductive networks have received extensive attention in wearable electronic sensors,electromagnetic shielding,and so on.However,the poor mechanical properties of the emerging nanofibers-based aerogels are limited in practical applications.In this work,we developed a synchronous deprotonation–protonation method in the KOH/dimethyl sulfoxide(DMSO)system at room temperature for achieving chitin cross-linked aramid nanofibers(CANFs)rather than chitin nanofibers(ChNFs)and aramid nanofibers(ANFs)separately by using chitin and aramid pulp as raw materials.After freeze-drying process,the cross-linked chitin/aramid nanofibers(CA)aerogel exhibited the synergetic properties of ChNF and ANF by the dual-nanofiber compensation strategy.The mechanical stress of CA aerogel was 170 kPa at 80%compressive strain,increased by 750%compared with pure ChNF aerogel.Similarly,the compressibility of CA aerogel was somewhat improved compared to ANF aerogel.The enhancement verified that the crosslinking reaction between ANF and ChNF during the synchronous deprotonation process was formed.Afterwards,the conductive aerogels with uniform porous structure(CA-M)were successfully obtained by vacuum impregnating CA aerogels in Ti_(3)C_(2)T_(x) MXene solution,displaying low thermal conductivity(0.01 W/(m·K)),high electromagnetic interference(EMI)shielding effectiveness(SE)(75 dB),flame retardant,and heat insulation.Meanwhile,the as-obtained CA-M aerogels were also applied as a pressure sensor with excellent compression cycle stability and superior human motion monitoring capabilities.As a result,the dual-nanofiber based conductive aerogels have great potentials in flexible/wearable electronics,EMI shielding,flame retardant,and heat insulation. 展开更多
关键词 synchronous deprotonation–protonation electromagnetic interference(EMI)shielding flame retardant heat insulation pressure sensing
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Strong light-matter coupling in van der Waals materials
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作者 Yuan Luo Jiaxin Zhao +10 位作者 Antonio Fieramosca Quanbing Guo Haifeng Kang Xiaoze Liu Timothy C.H.Liew Daniele Sanvitto Zhiyuan An Sanjib Ghosh Ziyu Wang Hongxing Xu Qihua Xiong 《Light(Science & Applications)》 SCIE EI CSCD 2024年第10期2009-2026,共18页
In recent years,two-dimensional(2D)van der Waals materials have emerged as a focal point in materials research,drawing increasing attention due to their potential for isolating and synergistically combining diverse at... In recent years,two-dimensional(2D)van der Waals materials have emerged as a focal point in materials research,drawing increasing attention due to their potential for isolating and synergistically combining diverse atomic layers.Atomically thin transition metal dichalcogenides(TMDs)are one of the most alluring van der Waals materials owing to their exceptional electronic and optical properties.The tightly bound excitons with giant oscillator strength render TMDs an ideal platform to investigate strong light-matter coupling when they are integrated with optical cavities,providing a wide range of possibilities for exploring novel polaritonic physics and devices.In this review,we focused on recent advances in TMD-based strong light-matter coupling.In the foremost position,we discuss the various optical structures strongly coupled to TMD materials,such as Fabry-Perot cavities,photonic crystals,and plasmonic nanocavities.We then present several intriguing properties and relevant device applications of TMD polaritons.In the end,we delineate promising future directions for the study of strong light-matter coupling in van der Waals materials. 展开更多
关键词 COUPLING LIGHT RENDER
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Review:Development of SARS-CoV-2 immuno-enhanced COVID-19 vaccines with nano-platform 被引量:2
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作者 Nawamin Sa-nguanmoo Katawut Namdee +3 位作者 Mattaka Khongkow Uracha Ruktanonchai YongXiang Zhao Xing-Jie Liang 《Nano Research》 SCIE EI CSCD 2022年第3期2196-2225,共30页
Vaccination is the most effective way to prevent coronavirus disease 2019(COVID-19).Vaccine development approaches consist of viral vector vaccines,DNA vaccine,RNA vaccine,live attenuated virus,and recombinant protein... Vaccination is the most effective way to prevent coronavirus disease 2019(COVID-19).Vaccine development approaches consist of viral vector vaccines,DNA vaccine,RNA vaccine,live attenuated virus,and recombinant proteins,which elicit a specific immune response.The use of nanoparticles displaying antigen is one of the alternative approaches to conventional vaccines.This is due to the fact that nano-based vaccines are stable,able to target,form images,and offer an opportunity to enhance the immune responses.The diameters of ultrafine nanoparticles are in the range of 1–100 nm.The application of nanotechnology on vaccine design provides precise fabrication of nanomaterials with desirable properties and ability to eliminate undesirable features.To be successful,nanomaterials must be uptaken into the cell,especially into the target and able to modulate cellular functions at the subcellular levels.The advantages of nano-based vaccines are the ability to protect a cargo such as RNA,DNA,protein,or synthesis substance and have enhanced stability in a broad range of pH,ambient temperatures,and humidity for long-term storage.Moreover,nano-based vaccines can be engineered to overcome biological barriers such as nonspecific distribution in order to elicit functions in antigen presenting cells.In this review,we will summarize on the developing COVID-19 vaccine strategies and how the nanotechnology can enhance antigen presentation and strong immunogenicity using advanced technology in nanocarrier to deliver antigens.The discussion about their safe,effective,and affordable vaccines to immunize against COVID-19 will be highlighted. 展开更多
关键词 COVID-19 SARS-CoV-2 VACCINE NANOTECHNOLOGY antigen presenting cells(APCs)
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In-situ growth of polypyrrole on aramid nanofibers for electromagnetic interference shielding films with high stability 被引量:4
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作者 Jianyu Zhou Sineenat Thaiboonrod +3 位作者 Jianhui Fang Shaomei Cao Miao Miao Xin Feng 《Nano Research》 SCIE EI CSCD 2022年第9期8536-8545,共10页
Flexible electromagnetic interference(EMI)shielding films with high stability have shown promising prospect in harsh working conditions such as military,communication,and special protection fields.Herein,flexible aram... Flexible electromagnetic interference(EMI)shielding films with high stability have shown promising prospect in harsh working conditions such as military,communication,and special protection fields.Herein,flexible aramid nanofibers@polypyrrole(ANF@PPy)films with high stability were easily achieved by the in-situ growth of PPy on the surface of ANF and the subsequent pressured-filtration film-forming process.When the amount of pyrrole(Py)monomer is 40μL,the ANF@PPy(AP40)film exhibited excellent EMI shielding performance with shielding effectiveness(SE)of 41.69 dB,tensile strength of 96.01 MPa,and fracture strain of 21.95%at the thickness of 75.76μm.Particularly,the anticipated EMI shielding performance can be maintained even after being heated at 200℃in air,soaked in 3.5%NaCl solution,repeated folding for one million times,or burned directly,indicating superior environmental durability in harsh conditions.Therefore,it is believed that the ANF@PPy films with high stability offer a facile solution for practical protection for high-performance EMI shielding applications. 展开更多
关键词 in-situ growth of polypyrrole(PPy)on aramid nanofibers(ANF) electromagnetic interference(EMI)shielding films high stability WATER-RESISTANCE thermal mechanical properties
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Bio-inspired Surface Structure for Slow-release of Urea Fertilizer 被引量:1
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作者 Methus Charoenchai Panida Prompinit +1 位作者 Wiyong Kangwansupamonkon Lapporn Vayachuta 《Journal of Bionic Engineering》 SCIE EI CSCD 2020年第2期335-344,共10页
In this work,bio-inspired concepts,including a Self-Healing(SH)and super hydrophobic structure,were used to produce slow-release of urea fertilizer.Following a bottom-up process,an SH layer on the urea granule was pro... In this work,bio-inspired concepts,including a Self-Healing(SH)and super hydrophobic structure,were used to produce slow-release of urea fertilizer.Following a bottom-up process,an SH layer on the urea granule was produced from a combination of two natural waxes,palm and carnauba,and fabricated by a hot-melt coating process in a pan coater.Another layer for super hydrophobicity was formed by a deposition of submicron-wax and carbon black particles on the SH layer to create a micro-nanostructure during coating.After the heat treatment,a smooth coating and even deposition of waxes throughout the urea surfaces were obtained.The properties of the waxes,a healing mechanism,and releasing profiles were examined using an optical microscope.After cracking of the coated urea surface,the intrinsic self-healing behavior was stimulated by heating the samples above 45℃C,corresponding to high ambient daytime temperatures.Air-trapping behavior was observed at the interphase of the water and coated urea,creating super hydrophobic granule surfaces which act as an invisible layer for water-penetration protection.The releasing profiles of the coated urea in soil revealed that the releasing periods could be significantly extended to four-times longer than those of the uncoated urea. 展开更多
关键词 bio-inspiration slow-release nitrogen FERTILIZER SELF-HEALING super HYDROPHOBICITY
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An analysis of F-doping in Li-rich cathodes 被引量:4
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作者 Trent Seaby Tong-En Lin +2 位作者 Yu-Xiang Hu Qing-Hong Yuan Lian-Zhou Wang 《Rare Metals》 SCIE EI CAS CSCD 2022年第6期1771-1796,共26页
Li-rich materials,due to their high capacity(>250 mAh·g^(-1)),have recently been considered as an alternative to the current generation of cathode materials for Li-ion batteries(LIBs).However,their inferior cy... Li-rich materials,due to their high capacity(>250 mAh·g^(-1)),have recently been considered as an alternative to the current generation of cathode materials for Li-ion batteries(LIBs).However,their inferior cycling stability limits their practical applicability.Doping is a common technique to solve this problem.However,anion doping remains relatively underexplored.Fluorine(F)is one of the most effective anion dopants owning to the improved capacity,cycling stability,and rate performance in batteries.The explanations and experimental results,however,vary significantly from study to study.Herein,we find that bulk F-doping significantly improves both rate performance and cycling stability,likely driven by charge compensation and greater electronegativity.Additionally,bulk F-doping occasionally improves capacity via enhanced activation and occasionally decreases capacity by preventing activation from occurring.Surface F-doping has similar effects to bulk F-doping on capacity and stability,while significantly hindering the rate performance.Furthermore,the improvements in surface-doped materials do not appear to be a result of specific surface modification,and instead can be ascribed to the effect of fluorine on the near-surface bulk material.Greater understanding of fluo-rine's influence on activation,in particular,is required to unlock the full potential of synergistic cation/anion co-doping. 展开更多
关键词 Li-rich materials Fluorine dopingi Normalization analysis Electrochemical performance
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Enhanced giant dielectric properties and improved nonlinear electrical response in acceptor-donor (Al^(3+), Ta^(5+))-substituted CaCu_(3)Ti_(4)0_(12) ceramics 被引量:2
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作者 Jakkree BOONLAKHORN Narong CHANLEK +3 位作者 Jedsada MANYAM Pornjuk SREPUSHARAWOOT Sriprajak KRONGSUK Prasit THONGBAI 《Journal of Advanced Ceramics》 SCIE CAS CSCD 2021年第6期1243-1255,共13页
The giant dielectric bchavior of CaCu_(3)Ti_(4)0_(12)(CCTO)has been widely investigated owing to its potential applications in electronics;however,the loss tangent(tan8)of this material is too large for many applicati... The giant dielectric bchavior of CaCu_(3)Ti_(4)0_(12)(CCTO)has been widely investigated owing to its potential applications in electronics;however,the loss tangent(tan8)of this material is too large for many applications.A partial substitution of CCTO ceramics with either Al^(3+) or Ta^(5+)-ions generally results in poorer nonlinear properties and an associated increase in tan8(to~0.29-1.15).However,first-principles calculations showed that self-charge compensation occurs between these two dopant ions when co-doped into Tit sites,which can improve the electrical properties of the grain boundary(GB).Surprisingly,in this study,a greatly enhanced breakdown electric field(~200--6588 V/cm)and nonlinear coefficient(-4.8-15.2)with a significantly reduced tan8(~0.010--0.036)were obtained by simultaneous partial substitution of CCTO with acceptor-donor(Al^(3+),Ta^(5+))dopants to produce(Al^(3+),Ta^(5+))-CCTO ceramics.The reduced tan8 and improved nonlinear properties were attributed to the synergistic effects of the co-dopants in the doped CCTO structure.The signifcant reduction in the mean grain size of the(Al^(3+),Ta^(5+))-CCTO ceramics compared to pure CCTO was mainly because of the Ta^(5+)-ions.Accordingly,the increased GB density due to the reduced grain size and the larger Schottky barrier height(Ф_(b))at the GBs of the co-doped CCTO ceramics were the main reasons for the greatly increased GB resistance,improved nonlinear properties,and reduced tan8 values compared to pure and single-doped CCTO.In addition,high dielectric constant values(ε'≈(0.52-2.7)×10^(4))were obtained.A fine-grained microstructure with highly insulating GBs was obtained by Ta doping,while co-doping with Ta^(5+) and Al^(3+ )resulted in a high Ф_(b).The obtained results are expected to provide useful guidelines for developing new giant dielectric ceramics with excellent dielectric properties. 展开更多
关键词 CaCu_(3)Ti_(4)0_(12)(CCTO) impedance spectroscopy nonlinear electrical properties dielectric constant loss tangent first-principles calculations
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Disease detection,severity prediction,and crop loss estimation in MaizeCrop using deep learning 被引量:1
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作者 Nidhi Kundu Geeta Rani +4 位作者 Vijaypal Singh Dhaka Kalpit Gupta Siddaiah Chandra Nayaka Eugenio Vocaturo Ester Zumpano 《Artificial Intelligence in Agriculture》 2022年第1期276-291,共16页
The increasing gap between the demand and productivity of maize crop is a point of concern for the food industry,and farmers.Its'susceptibility to diseases such as Turcicum Leaf Blight,and Rust is a major cause fo... The increasing gap between the demand and productivity of maize crop is a point of concern for the food industry,and farmers.Its'susceptibility to diseases such as Turcicum Leaf Blight,and Rust is a major cause for reducing its production.Manual detection,and classification of these diseases,calculation of disease severity,and crop loss estimation is a time-consuming task.Also,it requires expertise in disease detection.Thus,there is a need to find an alternative for automatic disease detection,severity prediction,and crop loss estimation.The promising results of machine learning,and deep learning algorithms in pattern recognition,object detection,and data analysis motivate researchers to employ these techniques for disease detection,classification,and crop loss estimation in maize crop.The research works available in literature,have proven their potential in automatic disease detection using machine learning,and deep learning models.But,there is a lack none of these works a reliable and real-life labelled dataset for training these models.Also,none of the existing works focus on severity prediction,and crop loss estimation.The authors in this manuscript collect the real-life dataset labelled by plant pathologists.They propose a deep learning-based framework for pre-processing of dataset,automatic disease detection,severity prediction,and crop loss estimation.It uses the K-Means clustering algorithm for extracting the region of interest.Next,they employ the customized deep learning model‘MaizeNet’for disease detection,severity prediction,and crop loss estimation.The model reports the highest accuracy of 98.50%.Also,the authors perform the feature visualization using the Grad-CAM.Now,the proposed model is integrated with a web application to provide a userfriendly interface.The efficacy of the model in extracting the relevant features,a smaller number of parameters,low training time,high accuracy favors its importance as an assisting tool for plant pathology experts.The copyright for the associated web application‘Maize-Disease-Detector’is filed with diary number:17006/2021-CO/SW. 展开更多
关键词 Disease detection Crop loss SEVERITY Deep learning MAIZE
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Cationic liposome of hen egg white lysozyme for enhanced its stability,activity and accessibility in gastro-intestinal tract
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作者 Mattaka Khongkow Natchanon Rimsueb +4 位作者 Angkana Jantimaporn Thitiphorn Janyaphisan Weerapong Woraprayote Wonnop Visessanguan Uracha Rungsardthong Ruktanonchai 《Food Bioscience》 SCIE 2023年第3期704-714,共11页
Hen egg white lysozyme(HEWL)is a food-derived antimicrobial protein,exhibiting bacteriolytic activity against several bacteria including foodborne enteric pathogens.It has been approved for using in food,pharmacologic... Hen egg white lysozyme(HEWL)is a food-derived antimicrobial protein,exhibiting bacteriolytic activity against several bacteria including foodborne enteric pathogens.It has been approved for using in food,pharmacological and therapeutic applications.However,using HEWL through the ingestion is still a challenge due to its poor stability and low bioavailability in the gastro-intestinal tract(GIT).Herein,liposomes incorporating with dimethyl dioctadecyl ammonium bromide(DDAB)were fabricated to encapsulate HEWL(Lip_HEWL_DDAB)for oral delivery.Lip_HEWL_DDAB was spherical with an average diameter of 162.7±1.6 nm and zeta potential of 37.1±4.3 mV.The Lip_HEWL_DDAB had high entrapment efficiency of 80%and 11%loading efficiency of HEWL.The formulated Lip_HEWL_DDAB were highly physicochemical stable in both simulated gastric fluid(SGF)and simulated intestinal fluid(SIF)and capable of enhancing the intestinal absorption via their mucoadhesive property while retaining antimicrobial activity against enteric bacteria.HEWL was released from Lip_HEWL_DDAB via diffusion mechanism at higher extent than those without the DDAB.Additionally,the prepared Lip_HEWL_DDAB was non-toxic at below 6.25μg/ml to intestinal cells and was able to deliver HEWL across an in vitro intestinal epithelium model,resulting in enhanced anti-microbial/anti-inflammatory activities,compared to their free-and unmodified-liposomal forms.Together,our modified cationic liposome is a new and promising strategy for improving oral delivery of HEWL with enhanced nutraceutical functions. 展开更多
关键词 Cationic liposome LYSOZYME Oral delivery Dimethyl dioctadecyl ammonium bromide(DDAB) LIPOSOME
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Polarization shaping of Poincare´ beams by polariton oscillations 被引量:1
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作者 David Colas Lorenzo Dominici +11 位作者 Stefano Donati Anastasiia A Pervishko Timothy CH Liew Ivan A Shelykh Dario Ballarini Milena de Giorgi Alberto Bramati Giuseppe Gigli Elena del Valle Fabrice P Laussy Alexey V Kavokin Daniele Sanvitto 《Light(Science & Applications)》 SCIE EI CAS CSCD 2015年第1期122-128,共7页
We propose theoretically and demonstrate experimentally the generation of light pulses whose polarization varies temporally to cover selected areas of the Poincare´sphere with both tunable swirling speed and tota... We propose theoretically and demonstrate experimentally the generation of light pulses whose polarization varies temporally to cover selected areas of the Poincare´sphere with both tunable swirling speed and total duration(1 ps and 10 ps,respectively,in our implementation).The effect relies on the Rabi oscillations of two polariton polarized fields excited by two counter-polarized and delayed pulses.The superposition of the oscillating fields result in the precession of the Stokes vector of the emitted light while polariton lifetime imbalance results in its drift from a circle of controllable radius on the Poincare´sphere to a single point at long times.The positioning of the initial circle and final point allows to engineer the type of polarization spanning,including a full sweeping of the Poincare´sphere.The universality and simplicity of the scheme should allow for the deployment of time-varying full-Poincare´polarization fields in a variety of platforms,timescales,and regimes. 展开更多
关键词 full Poincare beams POLARITONS POLARIZATION pulse shaping Rabi oscillations
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Microcavity exciton polaritons at room temperature 被引量:4
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作者 Sanjib Ghosh Rui Su +9 位作者 Jiaxin Zhao Antonio Fieramosca Jinqi Wu Tengfei Li Qing Zhang Feng Li Zhanghai Chen Timothy Liew Daniele Sanvitto Qihua Xiong 《Photonics Insights》 2022年第1期60-103,共44页
The quest for realizing novel fundamental physical effects and practical applications in ambient conditions has led to tremendous interest in microcavity exciton polaritons working in the strong coupling regime at roo... The quest for realizing novel fundamental physical effects and practical applications in ambient conditions has led to tremendous interest in microcavity exciton polaritons working in the strong coupling regime at room temperature.In the past few decades,a wide range of novel semiconductor systems supporting robust exciton polaritons have emerged,which has led to the realization of various fascinating phenomena and practical applications.This paper aims to review recent theoretical and experimental developments of exciton polaritons operating at room temperature,and includes a comprehensive theoretical background,descriptions of intriguing phenomena observed in various physical systems,as well as accounts of optoelectronic applications.Specifically,an in-depth review of physical systems achieving room temperature exciton polaritons will be presented,including the early development of ZnO and GaN microcavities and other emerging systems such as organics,halide perovskite semiconductors,carbon nanotubes,and transition metal dichalcogenides.Finally,a perspective of outlooking future developments will be elaborated. 展开更多
关键词 microcavity exciton polariton Bose-Einstein condensation exciton binding energy quantum simulation nonequilibrium dynamics
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Anisotropic robustness of talc particles after surface modifications probed by atomic force microscopy force spectroscopy
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作者 Vipada Dokmai Kitiphat Sinthiptharakoon +1 位作者 Witchukorn Phuthong Varong Pavarajarn 《Particuology》 SCIE EI CAS CSCD 2021年第5期308-315,共8页
As a versatile mineral,the crystalline hydrated magnesium silicate talcum,or talc,has been widely used in numerous industries from pharmaceutical formulations to composite material designs.Its efficient application as... As a versatile mineral,the crystalline hydrated magnesium silicate talcum,or talc,has been widely used in numerous industries from pharmaceutical formulations to composite material designs.Its efficient application as filler/additives incorporates the improvement in concomitant properties within materials,e.g.,strength,which involves interactions between talc particles and aqueous/nonaqueous matrices.Successful property enhancement imposes ideal mixing and homogenous adhesion within a talc particle,but they are limited by the coexistence of face and edge surfaces of talc,which exhibit different level of hydrophobicity.Here,using atomic force microscopy force spectroscopy,we showed that although hydrophilic talc particles obtained from acid treatment or aminosilanization better adhered with materials representing a matrix,the anisotropic characters of the two surface types persisted.Conversely,the degree of talc’s surface anisotropy reduced with the surface hydrophobization by aliphatic methylsilanization,but followed by the decrease in adhesion.With ten-fold difference in Hamaker constants of the probe/talc surface interacting pairs,we showed that the adhesions resulted from van der Waals interactions that suggested the influence of surface polarity.The insight from this work would provide grounds for strategies to modulate talc’s adhesion,hydrophobicity and surface uniformity. 展开更多
关键词 TALC Atomic force microscopy Force spectroscopy ADHESION Surface
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