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smILE soft X-ray Imager flight model CCd370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： s.Parsons d.J.Hall o.Hetherington T.W.Buggey T.Arnold m.W.J.Hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

Throughout the smILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their *** order to understand the changes of the CCd370s within the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance *** CCds have been characterised,the two flight devices and the flight spa *** has been carried out at the open University in a bespo ke cleanroom measure ment *** results show that there is a cluster of bright pixels in the flight spa re which increases in size with tempe *** at the nominal ope rating tempe rature(-120℃) it is within the procure ment ***,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science *** se rial charge transfer inefficiency degrades with temperature in full frame *** any charge losses are recovered when binning/frame transfer is implemented.

关键词： CCd soft X-ray imager characterisation smILE

The CCd instrument background of the smILE sXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： m.W.J.Hubbard o.Hetherington d.J.Hall T.W.Buggey s.Parsons T.Arnold A.Holland C.Pagani s.sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The EsA and CAs smILE mission orbit is highly elliptical and will pass through multiple radiation *** soft X-ray Imager(sXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCds(Charge-Coupled devices)that form the focal plane array of the sXI were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

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

Vanillylacetone attenuates cadmium chloride-induced hippocampal damage and memory loss through upregulation of nuclear factor erythroid 2-related factor 2 gene and protein expression

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Neural Regeneration Research 2024年第12期19卷 2750-2759页

作者： Fahaid H.A.L-Hashem salah o.Bashir Amal F.dawood moutasem s.Aboonq Ismaeel Bin-Jaliah Abdulaiziz m.Al-Garni mohamed d.morsy department of Physiology College of MedicineKing Khalid UniversityAbhaSaudi Arabia department of Basic medical sciences College of MedicinePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia department of Physiology College of MedicineTaibah UniversityAl-Madinah Al-MunawwarahSaudi Arabia department of medicine College of MedicineKing Khalid UniversityAbhaSaudi Arabia

memory loss and dementia are major public health concerns with a substantial economic *** stress has been shown to play a crucial role in the pathophysiology of hippocampal damage-induced memory *** investigate whether the antioxidant and anti-inflammatory compound vanillyla cetone(zingerone) can protect against hippocampal damage and memory loss induced by cadmium chloride(CdCl_(2)) administration in rats,we explo red the potential involvement of the nuclear factor erythroid 2-related factor 2(Nrf2) signaling pathway,which is known to modulate oxidative stress and *** healt hy male Wistar rats were divided into five groups:vehicle-treated(control),vanillylacetone,CdCl_(2),vanillylacetone+ CdCl_(2),vanillylacetone+ CdCl_(2)+ brusatol(a selective pharmacological N rf2inhibitor) *** effectively attenuated CdCl_(2)-induced damage in the dental gyrus of the hippocampus and improved the memory function assessed by the morris Water maze ***,vanillylacetone markedly decreased the hippocampal tissue levels of inflammatory biomarkers(interleukin-6,tumor necrosis factor-α,intracellular cell adhesive molecules) and apoptosis biomarkers(Bax and cleaved caspase-3).The control and CdCl_(2)-treated groups treated with va nillylacetone showed reduced generation of reactive oxygen species,decreased malondialdehyde levels,and increased superoxide dismutase and glutathione activities,along with significant elevation of nuclear Nrf2 mRNA and protein expression in hippocampal *** the protective effects of vanillylacetone we re substantially blocked by the co-administration of brusatol(a selective N rf2 inhibitor).Va nillylacetone mitigated hippocampal damage and memory loss induced by CdCl_(2),at least in part, by activating the nuclear transcription factor ***,vanillylacetone exerted its potent antioxidant and antiinflammatory actions.

关键词： hippocampus neuroprotective Nrf2 gene oxidative stress vanillylacetone

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.morassuti A.P.L silva L.A.o.Nunes s.m.Lima L.H.C.Andrade optical and Photothermal spectroscopy Group(GEoF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of são Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio optical thermometry Judd-ofelt Rare earths

Ion heat transport in electron cyclotron resonance heated L-mode plasma on the T-10 tokamak

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Plasma science and Technology 2024年第4期26卷 52-60页

作者： V.A.KRUPIN m.R.NURGALIEV A.R.NEmETs I.A.ZEmTsoV s.d.sUNTsoV T.B.mYALToN d.s.sERGEEV N.A.soLoVEV d.V.sARYCHEV d.V.RYJAKoV s.N.TUGARINoV N.N.NAUmENKo National Research Centre“Kurchatov Institute” Moscow 123182Russia Bauman moscow state Technical University Moscow 105005Russia Institution“Project Center ITER” Moscow 123098Russia JsC“soLAR” Minsk 220034Belarus

Anomalous ion heat transport is analyzed in the T-10 tokamak plasma heated with electron cyclotron resonance heating(ECRH) in second-harmonic extra-ordinary mode. Predictive modeling with empirical scaling for ohmical heat conductivity shows that in ECRH plasmas the calculated ion temperature could be overestimated, so an increase of anomalous ion heat transport is required. To study this effect two scans are presented: over the EC resonance position and over the ECRH power. The EC resonance position varies from the high-field side to the low-field side by variation of the toroidal magnetic field. The scan over the heating power is presented with on-axis and mixed ECRH regimes. discharges with high anomalous ion heat transport are obtained in all considered regimes. In these discharges the power balance ion heat conductivity exceeds the neoclassical level by up to 10 times. The high ion heat transport regimes are distinguished by three parameters: the ratio Te/Ti, the normalized electron density gradient R/■, and the ion–ion collisionality νii~*. The combination of high Te/Ti, high νii~*, and R/■=6-10 results in values of normalized anomalous ion heat fluxes up to 10 times higher than in the low transport scenario.

关键词： tokamak L-mode electron cyclotron resonance heating ion heat transport

Interfacial stress engineering toward enhancement of ferroelectricity in Al doped Hfo_(2)thin films

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Chinese Physics B 2024年第9期33卷 637-643页

作者： s X Chen m m Chen Y Liu d W Cao G J Chen department of microelectronics Jiangsu UniversityZhenjiang 212013China department of Physics Jiangsu UniversityZhenjiang 212013China Guangdong–Hong Kong–macao Joint Laboratory for Intelligent micro-Nano optoelectronic Technology Foshan UniversityFoshan 528225China

Ferroelectric Hfo_(2)has attracted much attention owing to its superior ferroelectricity at an ultra-thin thickness and good compatibility with si-based complementary metal-oxide-semiconductor(Cmos)***,the crystallization of polar orthorhombic phase(o-phase)Hfo_(2)is less competitive,which greatly limits the ferroelectricity of the as-obtained ferroelectric Hfo_(2)thin ***,the crystallization of o-phase Hfo_(2)can be thermodynamically modulated via interfacial stress *** this paper,the growth of improved ferroelectric Al doped Hfo_(2)(Hfo_(2):Al)thin films on(111)-oriented si substrate has been *** analysis has suggested that nonpolar monoclinic Hfo_(2):Al grown on(111)-oriented si substrate suffered from a strong compressive strain,which promoted the crystallization of(111)-oriented o-phase Hfo_(2)in the as-grown Hfo_(2):Al thin *** addition,the in-plane lattice of(111)-oriented si substrate matches well with that of(111)-oriented o-phase Hfo_(2),which further thermally stabilizes the o-phase Hfo_(2).Accordingly,an improved ferroelectricity with a remnant polarization(2P_(r))of 26.7C/cm^(2) has been *** results shown in this work provide a simple way toward the preparation of improved ferroelectric Hfo_(2)thin films.

关键词： improved ferroelectricity interfacial stress engineering compressive strain Hfo_(2)

Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)o_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： s.m.Yakout A.m.Youssef Inorganic Chemistry department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount *** the current study, we report the photocatalytic characteristics of four compositions composed of Tio_(2),Ti_(0.97)Cu_(0.03)o_(2), Ti_(0.965)Cu_(0.03)La_(0.005)o_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)o_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure Tio_(2)and Ti_(0.97)Cu_(0.03)o_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)o_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)o_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of Tio_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in Tio_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)o_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)o_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on sEm images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of Tio_(2). The resulting Ti_(0.97)Cu_(0.03)o_(2), Ti_(0.965)Cu_(0.03)La_(0.005)o_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)o_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)o_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)o_(2)catalyst can be clarified in terms of higher ch

关键词： semiconductor Tio_(2) Rare earths Congo red methylene blue solar spectrum Photodegradation

structural effects induced by dialysis-based purification of carbon nanomaterials

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Nano materials science 2024年第4期6卷 475-483页

作者： A.d.Veloso A.m.Ferraria A.m.Botelho do Rego A.s.Viana A.J.s.Fernandes A.J.Fielding R.A.Videira m.C.oliveira CQ-VR and Chemistry department University of Trás-os-Montes e Alto Douro BsIRG iBB-Institute for Bioengineering and BiosciencesDepartment of Chemical Engineeringand Associate Laboratory i4HB-Institute for Health and BioeconomyInstituto Superior TécnicoUniversidade de Lisboa Centro de Química Estrutural Institute of Molecular SciencesDepartamento de Química e BioquímicaFaculdade de CiênciasUniversidade de Lisboa I3N and Physics department University of AveiroCampus de Santiago Faculty of science Pharmacy and Biomolecular SchoolLiverpool John Moores University REQUImTE/LAQV Laborat orio de FarmacognosiaDepartamento de QuímicaFaculdade de Farm aciaUniversidade do Porto

dialysis plays a crucial role in the purification of nanomaterials but its impact on the structural properties of carbon nanomaterials was never ***,a carbon-based nanomaterial generated electrochemically in potassium phosphate buffer,was characterized before and after dialysis against pure *** is shown that dialysis affects the size of the carbon domains,structural organization,surface functionalization,oxidation degree of carbon,and grade of ***,dialysis drives the nanomaterial organization from discrete roundish carbon domains,with sizes ranging from 70 to 160 nm,towards linear stacking structures of small nanoparticles （m）.In parallel,alcohol and ether （epoxide） surface groups evolve into more oxidized carbon groups （e.g.,ketone and ester groups）.Investigation of the as-prepared nanomaterial by electron paramagnetic resonance （EPR） revealed a resonance signal consistent with carbon-oxygen centred ***,this study brings to light the selective affinity of the carbon nanomaterial under study to capture Na+ions,a property greatly enhanced by the dialysis process,and its high ability to trap oxygen,particularly before *** findings open new perspectives for the application of carbon-based nanomaterials and raise awareness of the importance of structural changes that can occur during the purification of carbon-based nanomaterials.

关键词： Nanocarbon surface functionalization NmR XPs Hydrophilic carbon Paramagnetic