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EP Aquarii:A new Picture of the Circumstellar Envelope

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Research in Astronomy and Astrophysics 2024年第3期24卷 83-105页

作者： pham t.nhung do t.Hoai Pierre darriulat pham tuan-Anh pham n.diep nguyen B.ngoc tran t.thai department of Astrophysics Vietnam National Space CenterVietnam Academy of Science and Technology18Hoang Quoc VietNghia DoCau GiayHa Noivietnam

new analyses of earlier ALMA observations of oxygen-rich AGB star EP Aquarii are presented,which complete a previously published analysis and offer a different interpretation of the morpho-kinematics of the circumstellar *** birth of the equatorial density enhancement(EdE)is shown to occur very close to the star where evidence for rotation has been *** to the star and where outflows have been observed:their interaction with the gas of the nascent EdE is seen to play an important role in the development of the wind and the evolution of its radial velocity from 8 to 10 km s^(-1) on the polar symmetry axis to~2 km s^(-1) at the *** implies complex morpho-kinematics:making reliable interpretations with reasonable confidence is *** particular,it questions an earlier interpretation implying the presence of a white dwarf companion orbiting the star at an angular distance of -0″4 from its *** proposes instead an interpretation in terms of a standard mass ejection associated with a shock wave leaving a void of emission in its *** doppler velocity wings are seen to consist of two components,the upper velocity end of the global wind,reaching above±12 km s^(-1),and an effective line broadening,confined within 200 mas from the center of the star,reaching above±20 km s^(-1) and interpreted as caused by the pattern of shock waves resulting from the interaction between stellar pulsation and convective cell partition.

关键词： stars AGB and post-AGB-(stars) circumstellar matter-radio lines stars

A concise review on surface and structural modification of porous zeolite scaffold for enhanced hydrogen storage

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Chinese Journal of Chemical Engineering 2024年第6期70卷 33-53页

作者： B.A.Abdulkadir R.S.R.Mohd Zaki A.t.Abd Wahab S.n.Miskan Anh-tam nguyen dai-Viet n.Vo H.d.Setiabudi Centre for Research in Advanced Fluid&Processes Universiti Malaysia Pahang Al-Sultan AbdullahLebuh Persiaran Tun Khalil YaakobGambangPahang 26300Malaysia Faculty of Chemical&Process Engineering technology Universiti Malaysia Pahang Al-Sultan AbdullahLebuh Persiaran Tun Khalil YaakobGambangPahang 26300Malaysia Center of Excellence for Green Energy and Environmental nanomaterials(CE@GrEEn) Nguyen Tat Thanh University300A Nguyen Tat ThanhDistrict 4Ho Chi Minh City 755414Viet Nam

Investigating zeolites as hydrogen storage scaffolds is imperative due to their porous nature and favorable physicochemical ***,the storage capacity of the unmodified zeolites has been rather unsatisfactory(0.224%-1.082%(mass))compared to its modified ***,the contemporary focus on enhancing hydrogen storage capacities has led to significant attention towards the utilization of modified zeolites,with studies exploring surface modifications through physical and chemical treatments,as well as the integration of various active *** enhanced hydrogen storage properties of zeolites are attributed to the presence of aluminosilicates from alkaline and alkaline-earth metals,resulting in increased storage capacity through interactions with the charge density of these ***,there is a great demand to critically review their role such as well-defined topology,pore structure,good thermal stability,and tunable hydrophilicity in enhanced hydrogen *** article aimed to critically review the recent research findings based on modified zeolite performance for enhanced hydrogen *** of the factors affecting the hydrogen storage capacities of zeolites that can affect the rate of reaction and the stability of the adsorbent,like pressure,structure,and morphology were studied,and ***,future perspectives,recommendations,and directions for modified zeolites were discussed.

关键词： Zeolites Hydrogen storage Surface modification Adsorption Active metal

detailed seismic zoning of the East Kazakhstan region in the Republic of Kazakhstan

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Geodesy and Geodynamics 2024年第2期15卷 156-165页

作者： natalya V.Silacheva n.P.Stepanenko O.K.Kurilova A.d.Kudabayeva A.t.danabayeva Institute of Seismology Ministry of Emergency SituationsAlmaty 050060Kazakhstan

Kazakhstan is currently drafting new construction regulations that comply with the major provisions of the *** regulations are created on the basis of seismic zoning maps of various degrees of detail,developed by our Institute of Seismology using a new methodological approach for *** article is about creating the first normative map of the detailed Seismic Zoning on a probabilistic foundation for the Republic of Kazakhstan’s East Kazakhstan *** carried out the probabilistic assessment of seismic hazard using a methodology consistent with the main provisions of Eurocode 8and updated compared with that used in developing maps of Kazakhstan’s General Seismic Zoning and seismic microzoning of *** most thorough and current data accessible for the area under consideration were combined with contemporary analytical *** have been done to not only the databases being used but also the way seismic sources were shown,including active faults *** a scale of 1:1000000,precise seismic zoning maps of the East Kazakhstan region were created for two probabilities of exceedance:10%and 2%in 50 years in terms of peak ground accelerations and macroseismic *** obtained seismic hazard distribution is generally consistent with the General Seismic Zoning of Kazakhstan’s previous ***,because active faults were included and a thoroughly revised catalog was used,there are more pronounced zones of increased danger along the fault in the western part of the *** the west of the territory,acceleration values also increased due to a more accurate consideration of seismotectonic *** maps are the basis for developing new state building regulations of the Republic of Kazakhstan.

关键词： Probabilistic seismic hazard assessment detailed seismic zoning Peak ground acceleration Microseismical intensity

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

排卵期女性用自然周期、改良自然周期或人工子宫内膜制剂进行一次冷冻胚胎移植后活产率的临床研究

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中国临床药理学杂志 2024年第16期40卷 2456-2456页

作者： HO V n A pham t d.nguyen n t 孟海峰

本研究为一项随机、开放标签研究,研究对象为18~45岁的排卵期女性,受试者按照1:1:1的比例被随机分为自然周期组、改良自然周期组或人工周期组。由于研究干预措施的性质特殊,故本试验不设盲。自然周期组不使用雌激素、孕酮或人绒毛膜促... 详细信息

本研究为一项随机、开放标签研究,研究对象为18~45岁的排卵期女性,受试者按照1:1:1的比例被随机分为自然周期组、改良自然周期组或人工周期组。由于研究干预措施的性质特殊,故本试验不设盲。自然周期组不使用雌激素、孕酮或人绒毛膜促性腺激素(hCG);改良自然周期组使用hCG来触发排卵;人工周期组使用口服戊酸雌二醇(从月经第2~4天开始,每天8mg)和阴道孕酮(从子宫内膜厚度≥7mm开始,每天800mg)。

关键词：人工周期戊酸雌二醇子宫内膜厚度活产率自然周期冷冻胚胎移植排卵期孕酮

Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu t.W.Huang K.Jiang C.n.Wu H.Peng P.C.hen R.Li H.B.Zhuo C.t.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

Measurement of yields and angular distributions ofγ-quanta from the interaction of 14.1 MeV neutrons with oxygen,phosphorus,and sulfur

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Chinese Physics C 2024年第3期48卷 79-92页

作者： d.n.Grozdanov n.A.Fedorov S.B.dabylova Yu.n.Kopatch I.n.Ruskov V.R.Skoy t.Yu.tretyakova C.Hramco P.I.Kharlamov G.V.Pampushik P.G.Filonchik A.V.Andreev Joint Institute for nuclear Research(JInR) DubnaRussia Institute for nuclear Research and nuclear Energy Bulgarian Academy of SciencesSofiaBulgaria Faculty of Physics Lomonosov Moscow State UniversityMoscowRussia L.n.Gumilyov Eurasian national University AstanaKazakhstan Skobeltsyn Institute of nuclear Physics Moscow State UniversityMoscowRussia Institute of Chemistry of Moldova ChisinauRepublic of Moldova Moscow Institute of Physics and technology MoscowRussia

A study of the inelastic scattering of neutrons with an energy of 14.1 MeV on the nuclei of oxygen,phosphorus,and sulfur was performed at the tAnGRA facility at JInR(dubna).the experiment aimed to refine existing data and obtain new data on the yields and angular distributions ofγ-quanta emitted by the studied nuclei due to neutron-induced nuclear reactions using the tagged neutron *** types of detector systems were used to registerγ-***γ-ray yields were measured using a high-purity germanium(HPGe)*** angular distributions ofγ-rays were obtained using a system of 18 scintillation detectors based on bismuth germanite Bi_(4)Ge_(3)O_(12)(BGO)located around the *** performed experiments measured the yields of two transitions for the reaction of tagged neutrons with 16O,nine transitions for the reaction with ^(31)P,and nine transitions for the reaction with ^(32)S for the first *** angular anisotropy of theγ-radiation accompanying the inelastic scattering of neutrons with an energy of 14.1 MeV on ^(31)P nuclei was also measured for the first time.

关键词： tagged neutron method yields of gamma-quanta high-resolution gamma-spectrometry neutron-nuclear reactions neutron scattering

Highly defective dark tiO_(2) Modified with Pt: Effects of Precursor nature and Preparation Method on Photocatalytic Properties

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transactions of tianjin University 2024年第2期30卷 198-209页

作者： E.d.Fakhrutdinova O.A.Reutova t.A.Bugrova I.Yu.Ovsyuk L.S.Kibis O.A.Stonkus d.B.Vasilchenko O.V.Vodyankina V.A.Svetlychnyi national Research tomsk State University TomskRussia 634050 novosibirsk State University NovosibirskRussia 630090 Boreskov Institute of Catalysis NovosibirskRussia 630090 nikolaev Institute of Inorganic Chemistry NovosibirskRussia 630090

the study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed CO adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) n) _(2) [Pt _(2) (OH) _(2) (nO _(3) ) _(8) ] were used. the sample featured a high content of single-atom species and subnano-sized Pt clusters. the X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (SMSI) eff ect of the transfer of electron density from the electron-saturated defects on the tiO _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the SMSI eff ect, exhibited the highest photocatalytic activity. the 0.5Pt(C)/tiO_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation.

关键词： dark(black)tiO_(2) Pulsed laser ablation Platinum reduction method Precursor type Photocatalysis Hydrogen evolution reaction

Boosting the catalytic activity toward oxygen reduction via a heterostructure of porous iron oxide-decorated 2d niO/nG nanosheets

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Journal of Energy Chemistry 2024年第6期93卷 669-681,I0016页

作者： Kakali Maiti Matthew t.Curnan Hyung Jun Kim Kyeounghak Kim Jeong Woo Han department of Chemical Engineering Pohang University of Science and Technology(POSTECH)PohangGyeongbuk 37673Republic of Korea department of Materials Science and Engineering Research Institute of Advanced MaterialsSeoul National UniversitySeoul 08826Republic of Korea department of Chemical Engineering Clean-Energy Research InstituteHanyang UniversitySeoul 04763Republic of Korea CSIR-Institute of Minerals and Materials technology RRL CampusAcharya ViharBhubaneswarOdisha 751013India

As a noble metal substitute,two-dimensional(2d)hierarchical nano-frame structures have attracted great interest as candidate catalysts due to their remarkable advantages-high intrinsic activity,high electron mobility,and straightforward surface ***,they may replace Pt-based catalysts in oxygen reduction reaction(ORR)***,a simple method is developed to design hierarchical nano-frame structures assembled via 2d niO and n-doped graphene(nG)*** procedure can yield nanostructures that satisfy the criteria correlated with improved electrocatalytic performance,such as large surface area,numerous undercoordinated atoms,and high defect ***,porous nG nanosheet architectures,featuring niO nanosheets densely coordinated with accessible holey Fe_(2)O_(3) moieties,can enhance mesoporosity and balance *** improvements can facilitate charge transport and expose formerly inaccessible reaction sites,maximizing active site density *** functional theory(dFt)calculations reveal favored O_(2) adsorption and dissociation on Fe_(2)O_(3) hybrid structures when supported by 2d niO and nG nanomaterials,given 2d materials donated charge to Fe_(2)O_(3) active *** systematic studies reveal that synergistic contributions are responsible for enriching the catalytic activity of Fe_(2)O_(3)@niO/nG in alkaline media-encompassing internal voids and pores,unique hierarchical support structures,and concentrated n-dopant and bimetallic atomic ***,this work expands the toolbox for designing and synthesizing highly efficient 2d/2d shelled functional nanomaterials with transition metals,endeavoring to benefit energy conversion and related ORR applications.

关键词： n-doped graphene Holey Fe_(2)O_(3)nanocrystals niO nanosheets High catalytic performance ORR