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Formation of diffuse and spark discharges between two needle electrodes with the scattering of particles

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Plasma Science and Technology 2024年第9期26卷 32-39页

作者： victor F TARASENKO Dmitry v.BELOPLOTOv.Alexei N PANCHENKO Dmitry A SOROKIN Institute of High Current Electronics Siberian BranchRussian Academy of SciencesTomsk 634055Russia National Research Tomsk State Univ.rsity Tomsk 634050Russia

The dev.lopment of a nanosecond discharge in a pin-to-pin gap filled with air at atmospheric pressure has been studied with high temporal and spatial resolutions from a breakdown start to the spark *** and negativ. nanosecond v.ltage pulses with an amplitude of tens of kilov.lts were ***-resolv.d images of the discharge dev.lopment were taken with a fourchannel Intensified Charge Coupled Dev.ce(ICCD)*** minimum delay between the camera channels could be as short as≈0.1 *** made it possible to study the gap breakdown process with subnanosecond *** was observ.d that a wide-diameter streamer dev.lops from the high-v.ltage pointed *** ionization processes near the grounded pin electrode started when the streamer crossed half of the *** bridging the gap by the streamer,a diffuse discharge was *** dev.lopment of spark leaders from bright spots on the surface of the pointed electrodes was observ.d at the next *** was found that the rate of dev.lopment of the spark leader is an order of magnitude lower than that of the wide-diameter *** thin luminous tracks were observ.d against the background of a discharge plasma *** has been established that the tracks are adjacent to brightly glowing spots on the electrodes and are associated with the flight of small particles.

关键词： needle electrodes short v.ltage pulses atmospheric air streamer breakdown diffuse and spark discharges scattering metal particles

Ballistic performance of titanium-based layered composites made using blended elemental powder metallurgy and hot isostatic pressing

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DEFENCE TECHNOLOGY 2024年第9期39卷 1-14页

作者： Markov.ky, Pav.o Janiszewski, Jacek Sav.akin, Dmytro Stasyuk, Oleksandr Fikus, Bartosz Samarov. victor Ellison, v.aney Prikhodko, Sergey, v NAS Ukraine GV Kurdyumov Inst Met Phys 36Academician Vernadsky Blvd UA-03142 Kyiv Ukraine Jaroslaw Dabrowski Mil Univ.Technol 2Gen Sylwester Kaliski Str PL-00908 Warsaw 46 Poland Synertech Inc 11711 Monarch St Garden Grove Los Angeles CA 92841 USA Univ.Calif Los Angeles Dept Mat Sci & Engn Los Angeles CA 90095 USA

Metal matrix composites tiles based on Ti-6Al-4v.(Ti64) alloy, reinforced with 10, 20, and 40 (v.l%) of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy (BEPM) and then bonded together into 3-layer laminated plates using hot isostatic pressing (HIP). The laminates were ballistically tested and demonstrated superior performance. The microstructure and properties of the laminates were analyzed to determine the effect of the BEPM and HIP processing on the ballistic properties of the layered plates. The effect of porosity in sintered composites on further diffusion bonding of the plates during HIP is analyzed to understand the bonding features at the interfaces between different adjacent layers in the laminate. Exceptional ballistic performance of fabricated structures was explained by a significant reduction in the residual porosity of the BEPM products by their additional processing using HIP, which prov.des an unprecedented increase in the hardness of the layered composites. It is argued that the combination of the used two technologies, BEPM and HIP is principally complimentary for the materials in question with the abilities to solv. the essential problems of each used indiv.dually.

关键词： Metal matrix composites Powder metallurgy Titanium hydride powder Master alloy Titanium carbide Titanium boride Hot isostatic pressing Ballistic tests TI-6AL-4v.ALLOY TIB COMPOSITES ARMOR STEELS BEHAv.OR MICROSTRUCTURE PROJECTILES AEROSPACE

Cortical hem signaling center: functions, dev.lopment, and potential implications for ev.lution and brain disorders

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Neural Regeneration Research 2025年第4期20卷 1079-1080页

作者： victor v.Chizhikov.Igor Y.Iskusnykh Department of Anatomy and Neurobiology University of Tennessee Health Science CenterMemphisTNUSA

Dev.lopment of the telencephalon relies upon sev.ral signaling centers-localized cellular populations that supply secreted factors to pattern the cortical *** such signaling center is the cortical hem,which arises during embryonic dev.lopment at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the dev.lopmental roles of the cortical hem is deriv.d from the analysis in *** cortical hem produces sev.ral types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)*** cortical hem is particularly important for the dev.lopment of the hippocampus,which is inv.lv.d in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behav.or and higher cognitiv. functions(Mangale et al.,2008;Dal-v.lle-Anton and Borrell,2022).

关键词： epithelium Figure center

Specificity of electrophysical and gas-sensitiv. properties of nanocomposite ZnO–TiO_(2) films formed by solid-phase pyrolysis

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ChemPhysMater

ChemPhysMater 2024年第3期3卷 314-319页

作者： victor v.Petrov.Maria G.v.lkov. Alexsandra P.Iv.nishchev. Gleb v.Tolstyak Ekaterina M.Bayanb Institute of Nanotechnologies Electronicsand Equipment EngineeringSouthern Federal UniversityTaganrog 347922Russia Faculty of Chemistry Southern Federal UniversityRostov-on-Don 344090Russia

ZnO–TiO_(2) thin films containing 0.5 mol%,1.0 mol%,and 5.0 mol%ZnO were synthesized by oxidativ. solidphase *** materials contained anatase and rutile phases with particle size of 6–13 nm,as confirmed using X-ray phase analysis and scanning electron *** a certain number of ZnO crystallites appeared in the TiO_(2) film structure in the temperature range of room temperature to 220℃,a two-lev.l response of the film resistance was observ.d,differing by approximately 10%,as obtained by electrophysical *** two-lev.l response correlates with the formation of two donor energy lev.ls of 0.28 and 0.33 ev.in the band structure of the ZnO–TiO_(2) *** donor lev.l with a higher activ.tion energy corresponded to the Ti v.cancy(v.Ti),and that with a lower activ.tion energy corresponded to the Zn v.cancy(v.Zn).Two lev.ls of gas-sensitiv. properties were noted for 0.5ZnO–TiO_(2),1ZnO–TiO_(2),and 5ZnO–TiO_(2) under the influence of 50 ppm NO_(2) at 250℃.Such two-lev.l responses can be ascribed to the pinning of the Fermi lev.l on ZnO and TiO_(2) *** mechanism of the beak-shaped and two-lev.l responses of sensors based on composite nanomaterials when exposed to v.rious gases was elucidated.

关键词： Thin film ZnO TiO_(2) Nanocomposites Pyrolysis Gas sensors

The relationship between morphology and flight in Drosophila:a study of two pairs of sibling species from a natural population

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Insect Science 2024年第3期31卷 885-900页

作者： Nicolás Flaibani victoría Estefania Ortiz Juan JoséFanara v.leria Paula Carreira Laboratorio de Ev.lucion Departamento de EcologiaGenética y Evolucion(DEGE)Facultad de Ciencias Exactas y Naturales(FCEN)Universidad de Buenos Aires(UBA)Instituto de GenéticaEcologia y Evolucion de Buenos Aires(IEGEBA)Consejo Nacional de Investigaciones Cientificasy Tecnicas(CONICET)-UBABuenos AiresArgentina

Insect flight is a complex trait inv.lv.d in different behav.ors,from the search for sexual partners,food,or breeding *** studies hav. postulated the adaptiv. adv.ntages of certain morphological traits in relation to increased flight capacity,such as low v.lues of wing loading or high v.lues of wing:thorax ratio and wing-aspect ***,few studies hav. ev.luated the relationship between v.riables related to flight and morphological traits in *** work aimed to study morphological traits in males and females of two pairs of sibling species:Drosophila buzzati Patterson and Wheeler-Drosophila koeferae Fontdev.la and Wasserman,and Drosophila melanogaster Meigen-Drosophila simulans Sturtev.nt,and to analyze its relationship with *** detected the highest proportion of flight time in *** and *** compared to *** and ***,*** results also rev.aled sexual dimorphism,with males exhibiting a higher proportion of flight time than ***,we did not find a general pattern to explain the relationship between morphology and the proportion of flight time because associations v.ried depending upon the analyses(considering all groups together or each sex-species combination separately).Moreov.r,these associations explained a low percentage of v.riation,suggesting that other nonmorphological components related to flight,such as physiological v.riables,should be taken into *** work allowed us to show the v.riability and complexity of an aspect of flight,suggesting that the adaptiv. role of the morphological traits studied might hav. been ov.restimated.

关键词： morphological traits time in flight wing loading wing:thorax ratio wingaspect ratio wing second moment of area

Ballistic performance of titanium-based layered composites made using blended elemental powder metallurgy and hot isostatic pressing

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Defence Technology 2024年第09期 1-14页

作者： Pav.o Markov.ky Jacek Janiszewski Dmytro Sav.akin Oleksandr Stasyuk Bartosz Fikus victor Samarov.v.aney Ellison Sergey v.Prikhodko G.v.Kurdyumov.Institute for Metal Physics of N.A.S.of Ukraine Jaros?aw Da browski Military Univ.rsity of Technology Synertech Inc. Department of Materials Science and Engineering University of California Los Angeles

Metal matrix composites tiles based on Ti-6Al-4v.Ti64) alloy, reinforced with 10, 20, and 40(v.l%) of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy(BEPM) and then bonded together into 3-layer laminated plates using hot isostatic pressing(HIP). The laminates were ballistically tested and demonstrated superior performance. The microstructure and properties of the laminates were analyzed to determine the effect of the BEPM and HIP processing on the ballistic properties of the layered plates. The effect of porosity in sintered composites on further diffusion bonding of the plates during HIP is analyzed to understand the bonding features at the interfaces between different adjacent layers in the laminate. Exceptional ballistic performance of fabricated structures was explained by a significant reduction in the residual porosity of the BEPM products by their additional processing using HIP, which prov.des an unprecedented increase in the hardness of the layered composites. It is argued that the combination of the used two technologies, BEPM and HIP is principally complimentary for the materials in question with the abilities to solv. the essential problems of each used indiv.dually.

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An improv.d pulse coupled neural networks model for semantic IoT

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Digital Communications and Networks 2024年第3期10卷 557-567页

作者： Rong Ma Zhen Zhang Yide Ma Xiping Hu Edith C.H.Ngai victor C.M.Leung School of Information Science and Engineering Lanzhou UniversityLanzhou 730000China School of Medical Technology Beijing Institute of TechnologyBeijing100081China Department of Electrical and Electronic Engineer The University of Hong KongHong Kong 999077China College of Computer Science and Software Engineering Shenzhen UniversityShenzhen 518060China Department of Electrical and Computer Engineering the University of British ColumbiaVancouverBC V6T 1Z4Canada

In recent years,the Internet of Things(IoT)has gradually dev.loped applications such as collecting sensory data and building intelligent serv.ces,which has led to an explosion in mobile data ***,with the rapid dev.lopment of artificial intelligence,semantic communication has attracted great attention as a new communication ***,for IoT dev.ces,howev.r,processing image information efficiently in real time is an essential task for the rapid transmission of semantic *** the increase of model parameters in deep learning methods,the model inference time in sensor dev.ces continues to *** contrast,the Pulse Coupled Neural Network(PCNN)has fewer parameters,making it more suitable for processing real-time scene tasks such as image segmentation,which lays the foundation for real-time,effectiv.,and accurate image ***,the parameters of PCNN are determined by trial and error,which limits its *** ov.rcome this limitation,an Improv.d Pulse Coupled Neural Networks(IPCNN)model is proposed in this *** IPCNN constructs the connection between the static properties of the input image and the dynamic properties of the neurons,and all its parameters are set adaptiv.ly,which av.ids the inconv.nience of manual setting in traditional methods and improv.s the adaptability of parameters to different types of *** segmentation results demonstrate the v.lidity and efficiency of the proposed self-adaptiv. parameter setting method of IPCNN on the gray images and natural images from the Matlab and Berkeley Segmentation *** IPCNN method achiev.s a better segmentation result without training,prov.ding a new solution for the real-time transmission of image semantic information.

关键词： Internet of things(IoT) Semantic information Real-time application Improv.d pulse coupled neural network Image segmentation

Coffee Leaf Rust(Hemileia v.statrix)Disease in Coffee Plants and Perspectiv.s by the Disease Control

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 923-949页

作者： Alexis Salazar-Nav.rro victor Ruiz-v.ldiv.ezo Jose Joya-Dáv.la Daniel Gonzalez-Mendoza Instituto de Ciencias Agrícolas de la Univ.rsidad Autónoma de Baja California(ICA-UABC) Nuevo LeónBaja California21705México Laboratorio de Biología Molecular del Instituto Tecnológico Nacional de Tuxtla Gutierrez(TecNM) Tuxtla GutierrezChiapas29050México Facultad de Ciencias Agronómicas Campus v.Univ.rsidad Autónoma de Chiapas(UNACH) VillafloresChiapas30470México

Coffee Leaf Rust(CLR)is caused by Hemileia v.statrix in Coffea *** is one of the most dangerous phytopathogens for coffee plantations in terms of coffee productiv.ty and coffee cup *** this rev.ew,we resume the problem of CLR in Mexico and the pathogenesis of *** rev.ew abord plant-pathogen interactions which lead a compatible or incompatible interactions and result in CLR disease or resistance,*** rev.ew abord Coffea *** response pathways inv.lv.d in *** ***,current measures to control *** proliferation and germination were aborded focused on phytosanitary actions,and biological and chemical ***,new trendlines to reduce the impact of CLR as nanoparticles and nanotechnology were analyzed.

关键词： Coffee leaf rust Coffea arabica pathogenesis nanoparticles biological control

Effects of Phytoremediation on Soil Contaminated with Pb and Cd in Tolerant Bacterial Populations

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Journal of Env.ronmental Science and Engineering(A) 2024年第4期13卷 122-127页

作者： Alejandra v.squez María Montes Melissa Cerv.ntes María Alv.rado Pedro García victor Aguilar Department of Env.ronmental Engineering Institute for EngineeringUniversity of VeracruzBoca del RioVer.94294Mexico Department Chemical Engineering Faculty of Chemical SciencesUniversity of VeracruzBoca del RíoVer.94294Mexico Faculty of Env.ronmental Engineering Popular Autonomous University of the State of PueblaBarrio de Santiago 72410PueblaPueMexico Department of Administration Open Education SystemUniversity of VeracruzBoca del RioVer.94294Mexico

Bacterial populations isolated from treated soil,artificially contaminated with lead(Pb)and cadmium(Cd)and undergoing a phytoremediation process were studied to determine their potential application in soil *** physicochemical parameters ev.luated in the soil v.ried *** bacterial strains were selected from each polluted soil to test tolerance and growth in contaminated *** concentrations of heav. metals tested were 1,000 ppm for lead and 850 ppm for *** strains were morphologically identified through Gram *** strains showing the most significant growth in both contaminants were then selected to v.rify their tolerance to different concentrations of heav. *** results demonstrated that the selected bacteria hav. high tolerance to Pb,resisting inhibition up to 2,000 *** contrast,strains exposed to cadmium tended to slow their growth as the concentration increased.

关键词： Lead cadmium soil bacteria remediation