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Numerical calculation of Z-scan measurements for nonlinear media with large phase shift

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Optoelectronics Letters 2024年第3期20卷 177-182页

作者： M.D.Zidan A.Allahham department of Physics Atomic Energy Commission of SyriaP.O.Box 6091DamascusSyria

We have reported the characteristics of a Z-scan for the poly(azaneylylidene-acylene)(DAZA) polymer, as nonlinear medium with a large nonlinear phase shift using continuous-wave(CW) laser beam. It has been verified that the Fresnel diffraction model is applicable for analyses of Z-scan measurements with DAZA polymer at high laser power. It was found that Z-scan curves with peak-to-valley features appear as the applied light intensity increases in the case of a large nonlinear phase shift. The Z-scan experiments were carried out using a CW laser to verify the theoretical calculations in the case of a large nonlinear phase shift model. Our results show good agreements between the experimental data and the proposed theoretical models.

关键词： nonlinear phase media

Evolution of Neoproterozoic siliciclastic Kerur Formation in the light of sequence stratigraphic framework: Badami Basin, Karnataka, India

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Journal of Palaeogeography 2024年第4期13卷 706-737页

作者： Soumik Mukhopadhyay Nipun Ghosh Pradip Samanta Arunava Sen Soumyadeep Bose department of Geological Sciences Jadavpur University atomic Minerals Directorate for Exploration and Research department of Geology University of North Bengal

Field-based sedimentology,state of the art facies analysis and sequence stratigraphic framework analysis have revealed the controls of local and global tectonics,basin-marginal slope,climate and changes in relative sea level （RSL） over the sedimentation pattern and evolution of a Neoproterozoic Kerur Formation within the Badami Group of Kaladgi Supergroup in *** entire succession shows three major cycles of *** study and fluvial architectural elemental analysis suggest considerable variations in depositional environments as well as palaeogeography.A transition from basin-margin alluvial cone deposits to braided system,initially with fluctuating ephemeral flows then to a steadier semi-perennial nature,is discernible within the 1stcycle,in response to decreasing depositional slope with rising water *** initial alluvial cone and braided ephemeral streams of high slope areas is designated as a product of low accommodation systems tract （LAST）,while the semi-perennial system with steadier flows,representing the axial river of the initial rift valley,appears to be a product of high-accommodation systems tract （HAST）.The 2ndcycle begins with a perennial and steady braided river system and grades upward to a shallow marine succession,comprising wave-dominated,well-sorted sandstone,with a granular transgressive lag at the ***,the bottommost fluvial interval of the 2ndcycle constitutes the lowstand systems tract （LST）.The marine succession represents deposits of outer shelf offshore to foreshore-beach settings and is composed of an initially deepening and fining upward transgressive systems tract （TST）,followed by a coarsening and shallowing upward highstand systems tract （HST） with a maximum marine flooding surface （MFS） in between,demarcated by a shale-rich condensed *** 3rdcycle,with its prograding alluvial fan and aggrading braided fluvial deposits and restricted occurrence,represents only the low accommodation systems tract（LAST） with

关键词： Neoproterozoic Kerur Formation Facies and architectural elemental analysis Palaeogeography Sequence stratigraphy Basin evolution

Study of plasma parameters of coaxial plasma source using triple Langmuir probe and Faraday cup diagnostics

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Plasma Science and Technology 2024年第4期26卷 94-100页

作者： Sunil KANCHI Rohit SHUKLA Archana SHARMA Pulsed Power and Electromagnetics Division Bhabha Atomic Research CentreVisakhapatnam 531011India Homi Bhabha National Institute Mumbai 400085India Beam Technology Development Group Bhabha Atomic Research CentreMumbai 400085India

Coaxial plasma guns are a type of plasma source that produces plasma which propagates radially and axially controlled by the shape of the ground electrode, which has attracted much interest in several applications. In this work, a 120° opening angle of CPG nozzle is used as a plasma gun configuration that operates at the energy of 150 J. The ionization of polyethylene insulator between the electrodes of the gun produces a cloud of hydrogen and carbon *** triple Langmuir probe and Faraday cup are used to measure plasma density and plasma temperature. These methods are used to measure the on-axis and off-axis plasma divergence of the coaxial plasma gun. The peak values of ion densities measured at a distance of 25 mm on-axis from the plasma gun are(1.6±0.5)×10^(19)m^(-3)and(2.8±0.6)×10^(19)m^(-3)for hydrogen and carbon plasma respectively and the peak temperature is 3.02±0.5 eV. The mean propagation velocity of plasma is calculated using the transit times of plasma at different distances from the plasma gun and is found to be 4.54±0.25 cm/μs and 1.81±0.18 cm/μs for hydrogen and carbon plasma respectively. The Debye radius is obtained from the measured experimental data that satisfies the thin sheath approximation. The shot-to-shot stability of plasma parameters facilitates the use of plasma guns in laboratory experiments. These types of plasma sources can be used in many applications like plasma opening switches, plasma devices, and as plasma sources.

关键词： coaxial plasma source triple Langmuir probe Faraday cup plasma density plasma temperature

Flavone improves liver damage in nicotine-exposed rats via the Nrf2/HO-1 pathway

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Asian Pacific Journal of Tropical Biomedicine 2024年第8期14卷 341-349页

作者： Nora A.Elsayed Fatma SM Moawed Esraa SA Ahmed Ahmed Hammad Omayma AR Abo-Zaid Biochemistry and Molecular Biology department Faculty of Vet.Med.Benha UniversityBenha cityEgypt Health Radiation Research National Center for Radiation Research and TechnologyEgyptian Atomic Energy AuthorityCairoEgypt Radiation Biology department National Center for Radiation Research and TechnologyEgyptian Atomic Energy AuthorityCairoEgypt

Objective:To assess the hepatoprotective effects of flavone on nicotine-induced liver ***:Thirty-six rats were allocated into six groups:the control group,the nicotine group,the flavone alone groups(10 and 25 mg/kg/body weight),and the nicotine groups treated with flavone(10 and 25 mg/kg/body weight).Liver function,oxidative stress,Nrf2 pathway(HO-1,Nrf2,and Keap-1),and inflammatory markers(IL-17,TNF-α,and NF-κB)were ***,a histopathological examination of liver tissues was ***:Nicotine increased liver damage,inflammation,and oxidative ***,flavone suppressed nicotine-induced liver enzymes,oxidative stress,and inflammation,as manifested by increased antioxidants and decreased malondialdehyde level,liver enzymatic activities,and inflammatory ***(10 and 25 mg/kg/body weight)also reduced the level of Keap-1 and increased HO-1 and Nrf2 levels in the liver of nicotine-exposed ***:Flavone has hepatoprotective properties and may slow the progression of liver injury by reducing oxidative stress,liver enzymes,and inflammation possibly via the Nrf2 pathway.

关键词： Flavone Nicotine Liver Nrf2 HO-1 NF-κB

Earth's core-mantle boundary shaped by the crystallization of a hydrous terrestrial magma ocean

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National Science Review 2024年第7期11卷 73-75页

作者： Qingyang Hu Jie Deng Yukai Zhuang Zhenzhong Yang Rong Huang Center for High Pressure Science and Technology Advanced Research(HPSTAR) Shanghai Advanced Research in Physical Sciences(SHARPS) department of Geosciences Princeton University Institute of atomic and Molecular Physics Sichuan University Key Laboratory of Polar Materials and Devices Department of Electronics East China Normal University

A water-rich global magma ocean(MO)likely existed in the early Hadean eon and subsequently cooled and *** water is an oxidant and is known to fundamentally affect liquid crystallization, the role of primordial water d... 详细信息

关键词： CROSSOVER MELT

Rationally construction of atomic-precise interfacial charge transfer channel and strong build-in electric field in nanocluster-based Zscheme heterojunctions with enhanced photocatalytic hydrogen production

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Nano Research 2024年第6期17卷 5002-5010页

作者： Qingtao Zhu Honglei Shen Chao Han Liu Huang Yanting Zhou Yuanxin Du Xi Kang Manzhou Zhu department of Materials Science and Engineering Centre for Atomic Engineering of Advanced MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationKey Laboratory of Functional Inorganic Material Chemistry of Anhui ProvinceAnhui UniversityHefei 230601China

The lack of effective charge transfer driving force and channel limits the electron directional migration in nanoclusters(NC)-based heterostructures,resulting in poor photocatalytic ***,a Z-scheme NC-based heterojunction(Pt1Ag28-BTT/CoP,BTT=1,3,5-benzenetrithiol)with strong internal electric field is constructed via interfacial Co-S bond,which exhibits an absolutely superiority in photocatalytic performance with 24.89 mmol·h^(−1)·g−1 H_(2)production rate,25.77%apparent quantum yield at 420 nm,and~100%activity retention in stability,compared with Pt1Ag28-BDT/CoP(BDT=1,3-benzenedithiol),Ag29-BDT/CoP,and *** enhanced catalytic performance is contributed by the dual modulation strategy of inner core and outer shell of NC,wherein,the center Pt single atom doping regulates the band structure of NC to match well with CoP,builds internal electric field,and then drives photogenerated electrons steering;the accurate surface S modification promotes the formation of Co-S atomic-precise interface channel for further high-efficient Z-scheme charge directional *** work opens a new avenue for designing NC-based heterojunction with matchable band structure and valid interfacial charge transfer.

关键词： atomically precise metal nanocluster Z-scheme heterojunction interfacial charge transfer build-in electric field photocatalytic hydrogen production

Optimization of extreme ultraviolet vortex beam based on high harmonic generation

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Chinese Physics B 2024年第5期33卷 459-464页

作者：肖礴赵逸文程方晶王革文姜威王一琛胡杰梁红静马日 Institute of atomic and Molecular Physics Jilin UniversityChangchun 130012China College of Science Jilin Institute of Chemical TechnologyJilin 132022China

In high harmonic generation(HHG),Laguerre–Gaussian(LG) beams are used to generate extreme ultraviolet(XUV)vortices with well-defined orbital angular momentum(OAM),which have potential applications in fields such as microscopy and *** experimental study on the HHG driven by vortex and Gaussian beams is conducted in this *** is found that the intensity of vortex harmonics is positively correlated with the laser energy and gas *** structure and intensity distribution of the vortex harmonics exhibit significant dependence on the relative position between the gas jet and the laser *** ring-like structures observed in the vortex harmonics,and the interference of quantum paths provide an explanation for the distinct structural ***,by adjusting the relative position between the jet and laser focus,it is possible to discern the contributions from different quantum *** optimization of the HH vortex field is applicable to the XUV,which opens up a new way for exploiting the potential in optical spin or manipulating electrons by using the photon with tunable orbital angular momentum.

关键词： high harmonic generation phase matching extreme ultraviolet vortex beam quantum path interference

Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.Sardar M.D.Hossain M.S.Sikder M.N.I.Khan M.R.Rahman Physics Discipline Khulna UniversityKhulna9208Bangladesh department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh department ofComputer Science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh Material Science Division Atomic Energy CentreDhaka1000Bangladesh

Spinel cubic ferrites have huge applications in me mory and high frequency *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscopy(FESEM),energy dispersive X-ray(EDX),vibrating sample magnetometer(VSM),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XRD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTIR analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FESEM images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EDX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Permeability EDX Resistivity

Heavy metal contamination and health risk assessment of road dust from landfills in Dhaka-Narayanganj, Bangladesh

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Emerging Contaminants 2024年第1期10卷 117-125页

作者： Mrittika Chakraborty Md Masudur Rahman Rahat Tasrina Rabia Choudhury Refayat Nigar Guorui Liu Ahsan Habib department of Chemistry University of DhakaDhaka1000Bangladesh Analytical Chemistry Laboratory Chemistry DivisionAtomic Energy Centre Dhaka Bangladesh Atomic Energy CommissionDhaka1000Bangladesh State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental ScienecsChinese Academy of SciencesBeijing100085China

In the recent years,air pollution has become an alarming issue for human health in many rapidly growing megacities including Dhaka and ***,pollution status and health risk have been assessed by the road dusts collected from landfills in Dhaka and Narayanganj through determination of heavy metals including Pb,Cd,Cr,As,Cu,Ni,Zn and Mn using atomic absorption *** collected dust samples have been grouped into three sizes,for example,150,75 and<75μm,to assess the degree of heavy metal accumulation in the dust *** dust particles were accumulated with high concentrations of Pb and As at Matuail landfills,whereas Cd,Cr,Zn,and Mn concentrations were highest at Narayanganj *** finer particles,for example 75μm,accumulated substantial concentrations of heavy *** index and pollution load index(PLI)results revealed that all of the sites were deteriorated by Pb,Cd,Cu,Zn and *** results exhibited that the quality of the Matuail landfill area was severely *** terms of non-carcinogenic health risk,the values of hazard quotient for ingestion were greater than those for inhalation and dermal *** adult groups,hazard index values for the Matuail landfills and medical waste incineration sites were greater than 1,while for the children groups,the values for the same areas,including the Narayanganj landfills,were also larger than *** values were at least one order of magnitude higher for the children groups than for the adult *** the results,it would be reasonable to draw the conclusion that non-carcinogenic health risks for children may be more prevalent in the relevant areas.

关键词： Road dusts Heavy metals Landfills Bangladesh Degree of accumulation Health risk assessment