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Development of an ultrathin liquid sheet target for laser ion acceleration at high repetition rates in the kilohertz range

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High Power Laser science and Engineering 2024年第3期12卷 134-145页

作者： M.Füle A.P.kovács T.Gilinger M.karnok P.Gaál s.Figul G.Marowsky k.Osvay National Laser-Initiated Transmutation Laboratory University of SzegedSzegedHungary Department of Experimental Physics University of SzegedSzegedHungary ELI ALPs ELI-HU Non-Profit Ltd.SzegedHungary Department of Optics and Quantum Electronics University of SzegedSzegedHungary Advanced Microfluidic systems GmbH GöttingenGermany

A colliding microjet liquid sheet target system was developed and tested for pairs of round nozzles of 10,11 and 18μm in *** sheet's position stability was found to be better than a few *** interaction with 50 mJ laser pulses,the 18μm jet has a resonance amplitude of 16μm at a repetition rate of 33 Hz,while towards 100 Hz it converges to 10μm for all nozzles.A white-light interferometric system was developed to measure the liquid sheet thickness in the target chamber both in air and in vacuum,with a measurement range of 182 nm±1μm and an accuracy of±3%.The overall shape and 3D shape of the sheet follow the Hasson±Peck model in *** vacuum versus air,the sheet gradually loses 10%of its thickness,so the thinnest sheet achieved was below 200 nm at a vacuum level of 10±4mbar,and remained stable for several hours of operation.

关键词： diagnostics laser ion acceleration nanometric liquid sheet targets vacuum test

Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： s.W.Wi Y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil University

We investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence sensitizer Rare earths

MDCN:Modified Dense Convolution Network Based Disease Classification in Mango Leaves

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Computers, Materials & Continua 2024年第2期78卷 2511-2533页

作者： Chirag Chandrashekar k.P.Vijayakumar k.Pradeep A.Balasundaram school of Computer science and Engineering Vellore Institute of Technology(VIT)ChennaiIndia Center for Cyber Physical systems School of Computer Science and EngineeringVellore Institute of Technology(VIT)ChennaiIndia

The most widely farmed fruit in the world is *** the production and quality of the mangoes are hampered by many *** diseases need to be effectively controlled and ***,a quick and accurate diagnosis of the disorders is *** convolutional neural networks,renowned for their independence in feature extraction,have established their value in numerous detection and classification ***,it requires large training datasets and several parameters that need careful *** proposed Modified Dense Convolutional Network(MDCN)provides a successful classification scheme for plant diseases affecting mango *** model employs the strength of pre-trained networks and modifies them for the particular context of mango leaf diseases by incorporating transfer learning *** data loader also builds mini-batches for training the models to reduce training ***,optimization approaches help increase the overall model’s efficiency and lower computing *** employed on the MangoLeafBD Dataset consists of a total of 4,000 *** the experimental results,the proposed system is compared with existing techniques and it is clear that the proposed algorithm surpasses the existing algorithms by achieving high performance and overall throughput.

关键词： Leaf disease detection deep convolutional neural networks transfer learning optimization MangoLeafBD Dataset

Long Term X-Ray spectral Variations of the seyfert-1 Galaxy Mrk 279

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Research in Astronomy and Astrophysics 2024年第6期24卷 307-314页

作者： k.Akhila Ranjeev Misra savithri H.Ezhikode k.Jeena Department of Physics Providence Women’s CollegeUniversity of CalicutKerala 673009India Inter-University Centre for Astronomy and Astrophysics(IUCAA) PB No.4GaneshkhindPune 411007India Department of Physics and Electronics CHRIST(Deemed to be University)Hosur Main RoadBangalore 560029India

We present the results from a long term X-ray analysis of Mrk 279 during the period 2018–*** use data from multiple missions–Astrosat,NusTAR and XMM-Newton,for the *** X-ray spectrum can be modeled as a double Comptonization along with the presence of neutral Fe kαline emission,at all *** determined the source’s X-ray flux and luminosity at these different *** find significant variations in the source’s flux *** also investigate the variations in the source’s spectral components during the observation *** find that the photon index and hence the spectral shape follow the variations only over longer time *** probe the correlations between fluxes of different bands and their photon indices,and found no significant correlations between the parameters.

关键词： galaxies:seyfert galaxies:individual(Mrk 335) X-rays:galaxies

Direct-seeded Rice: Genetic Improvement of Game-Changing Traits for Better Adaption

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Rice science 2024年第4期31卷 417-433页

作者： Priyanka NEGI Jagadish RANE Rajendra sadashiv WAGH Tukaram Jayaram BHOR Dipti Digambar GODsE Priyanka JADHAV C.ANILkUMAR Dasari sREEkANTH k.sAMMI REDDY sharad Ramrao GADAkH k.M.BORAIH C.B.HARIsHA P.s.BAsAVARAJ Indian Council of Agricultural Research(ICAR)-National Institute of Abiotic stress Management Baramati 413115India Mahatma Phule krishi Vidyapeeth Rahuri 413722India ICAR-Central Institute for Arid Horticulture Bikaner 334006India ICAR-National Rice Research Institute Cuttack 753006India ICAR-Directorate of Weed Research Jabalpur 482004India Dr.Panjabrao Deshmukh krishi Vidyapeeth Akola 444104India

The sustainability of rice production continues to be a subject of uncertainty and inquiry attributed to shifts in climatic conditions. In light of the impending climate change crisis and the high labor and water costs accompanying it, direct-seeded rice(DsR) is unquestionably one of the most practical solutions. Despite its resource and climate-friendly advantages, early maturing rice faces weed competitiveness and seedling establishment challenges. Resolving these issues is crucial for promoting its wider adoption among farmers, presenting it as a more effective sustainable rice cultivation method globally. Diverse traditional and contemporary breeding methods are employed to mitigate the limitations of the DsR approach, leveraging advanced techniques such as speed breeding and genome editing. Focusing on key traits like mesocotyl length elongation, early seedling vigor, root system architecture, and weed competitiveness holds promise for transformative improvements in DsR adaptation at a broader scale within farming communities. This review aims to summarize how these features contribute to increased crop production in DsR conditions and explore the research efforts focusing on enhancing DsR adaptation through these traits. Emphasizing the pivotal role of these game-changing traits in DsR adaptation, our analysis sheds light on their potential transformative impact and offers valuable insights for advancing DsR practices.

关键词： climate change direct-seeded rice aerobic rice early vigor trait

First evidence for chiral wobbling of triaxial nuclei

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Nuclear science and Techniques 2024年第7期35卷 4-7页

作者： s.Frauendorf Department of Physics and Astronomy University of Notre DameNotre DameIN 46556USA

Chirality(Greek“handiness”)is a property of many com-plex *** molecules exist in two forms,one being the mirror image of the *** for our hands,it is impossible to make the images identical by a suitable *** two forms are called left-handed and *** have the same binding energy,because the electro-magnetic interaction,which holds the molecule together,does not change under a *** properties that are insensitive to the geometry are also the *** different geometry is the reason why the left-handed form turns the polarization plane of transmitted light in one direction by some angle while the right-handed form turns it in the oppo-site direction by the same ***,the geometrical differences between the two species may have other *** two species of the carvon molecule shown in Fig.1 taste quite differently.

关键词： turns Chiral mirror

Tribological behavior of lubricant-impregnated porous polyimide

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Friction 2024年第4期12卷 711-725页

作者： Jinbang LI Ningning ZHOU Janet s.s.WONG school of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China Beijing key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of Control EngineeringBeijing 100029China Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK

Porous materials impregnated with lubricants can be used in conditions where limited lubricant is *** this work,three porous polyimides(PPI)with different densities were ***(PAO)impregnated PPI(iPPI)discs were rubbed against steel and sapphire *** operando observations of the iPPI-sapphire contacts show that oil is released under an applied load,forming a meniscus around *** at the outlet is created at high sliding *** amount of released oil increases with increasing PPI *** moduli,E*,estimated based on the actual contact size show that trapped oil in iPPIs contributes to load *** higher speeds,tribological rehydration of the contact occurs in low density iPPI,with that E*rises with *** high density PPIs,high speeds give a constantly high E*which is limited by the viscoelastic properties of the PPI network and possibly the rate of oil *** of iPPI-steel contacts is governed by the mechanical properties of the PPI,the flow of the lubricant,and the roughness of the PPI *** low-and medium-density(highly porous,high roughness)PPIs,large amount of oil is released,and lubrication is mainly via lubricant restricted in the contact in the pores and possibly tribological *** high density(low porosity)PPI,with lower roughness,hydrodynamic lubrication is achieved which gives the lowest *** results show that polymeric porous materials for effective lubrication require the optimization of its surface roughness,stiffness,oil flow,and oil retentions.

关键词： polyimide porous material friction mechanism polymer limited lubrication

Prevalence and associated factors of clubfoot in the eastern province of saudi Arabia: A hospital-based study

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World Journal of Orthopedics 2024年第7期15卷 635-641页

作者： Ammar k Alomran Bandar A Alzahrani Bader s Alanazi Mohammed A Alharbi Loay M Bojubara Eman M Alyaseen Department of Orthopedic College of MedicineImam Abdulrahman bin Faisal UniversityDammam 34212Saudi Arabia College of Medicine Imam Abdulrahman bin Faisal UniversityDammam 34212Saudi Arabia College of Medicine Arabian Gulf UniversityManama 329Bahrain

BACkGROUND Clubfoot,or congenital talipes equinovarus,is a widely recognized cause of disability and congenital deformity worldwide,which significantly impacts the quality of *** management of clubfoot requires long-term,multidiscip-linary *** is important to understand how common this condition is in order to assess its impact on the ***,few studies have investigated the prevalence of clubfoot in saudi *** To determine the prevalence of clubfoot in saudi Arabia via the patient population at king Fahad University Hospital(kFUH).METHODs This was a retrospective study conducted at one of the largest hospitals in the country and located in one of the most densely populated of the administrative *** Of the 7792 births between 2015 to 2023 that were included in the analysis,42 patients were diagnosed with clubfoot,resulting in a prevalence of 5.3 per 1000 live births at *** The observed prevalence of clubfoot was significantly higher than both global and local estimates,indicating a substantial burden in the study population.

关键词： Clubfoot Talipes equinovarus Congenital talipes equinovarus Prevalence saudi Arabia

Metrology for sub-Rayleigh-length target positioning in~10^(22)W/cm^(2)laser-plasma experiments

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High Power Laser science and Engineering 2024年第3期12卷 90-105页

作者： E.A.Vishnyakov A.sagisaka k.Ogura T.Zh.Esirkepov B.Gonzalez-Izquierdo C.D.Armstrong T.A.Pikuz s.A.Pikuz W.Yan T.M.Jeong s.singh P.Hadjisolomou O.Finke G.M.Grittani M.Nevrkla C.M.Lazzarini A.Velyhan T.Hayakawa Y.Fukuda J.k.koga M.Ishino k.kondo Y.Miyasaka A.kon M.Nishikino Y.V.Nosach D.khikhlukha I.P.Tsygvintsev D.kumar J.Nejdl D.Margarone P.V.sasorov s.Weber M.kando H.kiriyama Y.kato G.korn k.kondo s.V.Bulanov T.kawachi A.s.Pirozhkov ELI Beamlines Facility The Extreme Light Infrastructure ERICDolníBrežanyCzech Republic kansai Institute for Photon science(kPsI) QSTKyotoJapan Central Laser Facility Rutherford Appleton LaboratorySTFCHarwell OxfordDidcotUK Institute for Open and Transdisciplinary Research Initiatives Osaka UniversityOsakaJapan HB11 Energy Holdings FreshwaterAustralia key Laboratory for Laser Plasmas(Ministry of Education) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFsA Shanghai Jiao Tong UniversityShanghaiChina Institute of Plasma Physics AsCR PragueCzech Republic FZU-Institute of Physics AsCR PragueCzech Republic Czech Technical University in Prague FNSPEPragueCzech Republic Institute of Laser Engineering Osaka UniversityOsakaJapan Institute of Physics National Academy of Sciences of UkraineKyivUkraine IsTEQ AR YerevanArmenia

Tight focusing with very small f-numbers is necessary to achieve the highest at-focus ***,tight focusing imposes strong demands on precise target positioning in-focus to achieve the highest on-target irradiance We describe several near-infrared,visible,ultraviolet and soft and hard X-ray diagnostics employed in a~10^(22)W/cm^(2)laser±plasma *** used nearly 10 J total energy femtosecond laser pulses focused into an approximately1.3-μm focal spot on 5±20μm thick stainless-steel *** discuss the applicability of these diagnostics to determine the best in-focus target position with approximately 5μm accuracy(i.e.,around half of the short Rayleigh length)and show that several diagnostics(in particular,3ωreflection and on-axis hard X-rays)can ensure this *** demonstrated target positioning within several micrometers from the focus,ensuring over 80%of the ideal peak laser intensity *** approach is relatively fast(it requires 10±20 laser shots)and does not rely on the coincidence of low-power and high-power focal planes.

关键词： laser-plasma interaction precise target positioning spectroscopy ultra-high intensity X-rays