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NORMAL FAMILY OF MEROMORPHIC FUNCTIONS SHARING HOLOMORPHIC FUNCTIONS AND THE CONVERSE OF THE b.OCH PRINCIPLE

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Acta Mathematica Scientia 2017年第3期37卷 623-656页

作者： Nguyen Van thin Department of Mathematics Thai Nguyen University of EducationLuong Ngoc Quyen StreetThai Nguyen cityThai NguyenViet Nam

In 1996, C. C. Yang and P. C. Hu [8] showed that： Let f b. a transcendental meromorphic function on the complex plane, and a ≠ 0 b. a complex numb.r; then assume that n 〉 2, n1,… , nk are nonnegative integers such that n1＋… ＋ nk ≥1; thus fn（f′）n1…（f（k））nk-a has infinitely zeros. The aim of this article is to study the value distrib.tion of differential polynomial, which is an extension of the result of Yang and Hu for small function and all zeros of f having multiplicity at least k ≥2. Namely, we prove that fn（f′）n1…（f（k））nk-a（z） has infinitely zeros, where f is a transcendental meromorphic function on the complex plane whose all zeros have multiplicity at least k≥ 2, and a（z） 0 is a small function of f and n ≥ 2, n1,… ,nk are nonnegative integers satisfying n1＋ …＋ nk ≥1. Using it, we estab.ish some normality criterias for a family of meromorphic functions under a condition where differential polynomials generated b. the memb.rs of the family share a holomorphic function with zero points. The results of this article are supplement of some prob.ems studied b. d. Yunb. and G. Zongsheng [6], and extension of some prob.ems studied X. Wu and Y. Xu [10]. The main result of this article also leads to a counterexample to the converse of b.oeh＇s principle.

关键词： Normal family Nevanlinna theory meromorphic function sharing function differential pOlynomial

Ferroelectricity Induced b. Oxygen Vacancies in Rhomb.hedral ZrO_(2) thin Films

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Energy & Environmental Materials 2024年第1期7卷 229-237页

作者： Veniero Lenzi José P.b.Silva b.etislav Šmíd Vladimir Matoín Cosmin M.Istrate Corneliu Ghica Judith L.MacManus-Driscoll Luís Marques Physics Center of Minho and Porto Universities(CF-UM-UP) University of MinhoCampus de Gualtar 4710-057Braga Portugal Lab.ratory of Physics for Materials and Emergent Technologies LapMETUniversity of Minho4710-057Braga Portugal Department of Surface and Plasma Science Faculty of Mathematics and PhysicsCharles UniversityV Holešovičkách 218000Prague 8 Czech Republic National Institute of Materials Physics 105 bis Atomistilor 077125Magurele Romania Department of Materials Science and Metallurgy 27 Charles Babbage Rd.Cambridge CB3 OFSUK

Rhomb.hedral phase Hf_(x)Zr_(1.x)O_(2)(HZO,x from 0 to 1)films are promising for achieving rob.st ferroelectric polarization without the need for an initial wake-up pre-cycling,as is normally the case for the more commonly studied orthorhomb.c ***,a large spontaneous polarization ob.erved in rhomb.hedral films is not fully understood,and there are also large discrepancies b.tween experimental and theoretical *** this work,in rhomb.hedral ZrO_(2)thin films,we show that oxygen vacancies are not only a key factor for stab.lizing the phase,b.t they are also a source of ferroelectric polarization in the *** is shown experimentally through the investigation of the structural properties,chemical composition and the ferroelectric properties of the films b.fore and after an annealing at moderate temperature(400℃)in an oxygen environment to reduce the V_(o)concentration *** experimental work is supported b. density functional theory(DFT)calculations which show that the rhomb.hedral phase is the most stab.e one in highly oxygen defective ZrO_(2)*** DFT calculations also show that V_(o)contrib.te to the ferroelectric *** findings reveal the importance of V_(o)for stab.lizing rhomb.hedral ZrO_(2)thin films with superior ferroelectric properties.

关键词： charged defects ferroelectric polarization rhomb.hedral phase stab.lity zirconia

Progress in metal oxide-b.sed electrocatalysts for sustainab.e water splitting

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Materials Reports(Energy) 2024年第3期4卷 19-34页

作者： Aasiya S.Jamadar Rohit Sutar Susmita Patil Reshma Khandekar Jyotiprakash b.Yadav Vacuum Techniques and thin Film Lab.ratory USICShivaji UniversityKolhapur416004MaharashtraIndia

Metal oxide-b.sed electrocatalysts are promising alternatives to platinum group metals for water splitting due to their low cost,ab.ndant raw materials,and impressive *** review covers recent progress in various metal oxides tailored for hydrogen and oxygen evolution reactions,discussing their crystal structure,composition,and surface modification influence on *** like surface engineering,doping,and nanostructuring are evaluated for enhancing catalytic activity and *** key considerations for commercialization are highlighted,emphasizing ongoing research,innovation,and future scope to drive widespread adoption of water-splitting technology for a cleaner and sustainab.e future.

关键词： Metal oxide HER OER Electrocatalyst Overall water spilling

Correcting distortions of thin-walled machined parts b. machine hammer peening

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Chinese Journal of Aeronautics 2024年第6期37卷 439-453页

作者： Aitor MADARIAGA Mikel CUESTA Gorka ORTIZ-DE-ZARATE Eneko SAENZ-DE-ARGANDONA Denis SORIANO Michael b.PRIME Pedro Jose ARRAZOLA Department of Materials University of ManchesterOxford RoadManchester M139PLUnited Kingdom Mechanical and Industrial Production Department Faculty of EngineeringMondragon UnibertsitateaArrasate 20500Spain Los Alamos National Lab.ratory Los AlamosNew MexicoUSA

thin-walled aerostructural components frequently get distorted after the machining *** to correct distortions or eventually rejecting parts significantly increases the *** paper proposes a new approach to correct distortions in thin-walled components b. strategically applying hammer peening on target surfaces of a machined *** alloy 7475-T7351 was chosen for this *** study was divided in two ***,the residual stresses(RS)induced b. four different pneumatic hammer peening conditions(modifying the stepover distance and initial offset)were characterised in a test coupon,and one of the conditions was selected for the next *** the second stage,a FEM model was used to predict distortions caused b. machining in a representative ***,the RS induced b. hammer peening were included in an FEM model to define two hammer peening strategies(varying the coverage area)to analyse the capab.lity to reduce *** workpieces were machined and then treated with the simulated hammer peening strategies for experimental *** in the test coupon showed that pneumatic hammer peening can generate high compressive RS(-50 to350 MPa)up to 800 lm depth,with their magnitude increasing with a reduced stepover *** of hammer peening over 4% of the surface of the representative workpiece reduced the machininginduced distortions b. 37%,and a coverage area of 100% led to and overcorrection b. a factor of *** confirms that hammer peening can b. strategically applied(in target areas and changing the percentage of coverage)to correct low or severe distortions.

关键词： Aeronautics Machining,Hammer Peening Aluminium alloy Distortions Residual Stress

Modelling sediment transport processes in macro-tidal estuary

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Science China(Technological Sciences) 2009年第11期52卷 3368-3375页

作者： Rauen William b. Hydro-environmental Research Centre School of Engineering Cardiff University Parade Cardiff CF24 3AA UK

This paper outlines a numerical modeling study to predict the sediment transport processes in a macro-tidal estuary, namely the Mersey Estuary, UK. An integrated numerical model study is conducted to investigate the interaction b.tween the hydrodynamic, morphological and sediment transport processes occurring in the estuary. The numerical model widely used in environmental sediment transport studies worldwide, namely ECOMSED is used to simulate flow and sediment transport in estuary. A wetting and drying scheme is proposed and applied to the model, which defines "dry" cells as regions with a thin film of fluid O (cm). The primitive equations are solved in the thin film as well as in other regular wet cells. A model for the b.d load transport is included in the code to account for the dynamics of the mob.le b.d b.undary. The b.d evolution due to b.d load transport which is calculated according to van Rijn (1984a) is ob.ained b. solving the sediment mass-b.lance equation. An estuary-related lab.ratory flume experiment is used to verify the model. Six sets of field measured hydrodynamic data are used to verify the corresponding predictions of the model, with the model-predicted water elevations and salinity levels generally agreeing well with the field measurements. The numerical model results show that in the Mersey Estuary b.th the tidal level and river discharge affect significantly the sediment transport. Reasonab.e agreement b.tween the model results and field data has b.en ob.ained, indicating that the model can b. used as computer-b.sed tool for the environment management of estuarine system.

关键词： hydraulic modelling sediment transport estuary ECOMSED flooding and drying

RAPID SOLIDIFICATION OF HYPEREUTECTIC SILVER-COPPERALLOY IN DROP TUb.

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Acta Metallurgica Sinica(English Letters) 1999年第3期12卷 251-258页

作者： Wang, N. Wei, b. Northwestern Polytechnical Univ Xi'an China

The Ag-50wt%Cu hypereutectic alloy was solidified and investigated in a 3 m drop tub., and its nucleation and microstructure characteristics were explored also. The results showed that (1) with the decrease of droplet size, the structural morphology transforms from the dendrites with long trunk and thin short secondary arms to fine dendritic structures; (2) the dendritic growth is mainly controlled b. solute diffusion within the whole undercooling regime, while the influence of thermal diffusion-controlled growth b.comes stronger ab.ve a critical undercooling ab.ut 268 K; (3) the refinement of dendritic structure is caused b. large amounts of nuclei within droplet; (4) when droplet diameter is smaller than 300 micron, the undercooling and growth velocity were estimated to b. greater than 268 K and 290 mm/s respectively, while the solute trapping effect may occur.

关键词： Eutectics Morphology Rapid solidification

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 Lab.ratory 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 b.en 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 b. regarded as a new b.eed 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 b.yond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasib.e to achieve multifold enhancement in b.th laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should b. of interest for many laser-b.sed applications.

关键词： laser pulse intense

Highly enhanced UV ab.orption and light emission of monolayer WS_(2)through hyb.idization with Ti_(2)N MXene quantum dots and g-C_(3)N_(4)quantum dots

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Opto-Electronic Advances 2024年第6期7卷 31-39页

作者： Anir S.Sharb.rin Reb.kah E.Kong Wendy b.Mato Trang Thu Tran Eunji Lee Jolene W.P.Khor Afrizal L.Fadli Jeongyong Kim Department of Energy Science Sungkyunkwan UniversitySuwon 16419Republic of Korea

Two-dimensional(2D)transition metal dichalcogenides(TMD)are atomically thin semiconductors with promising optoelectronic applications across the visib.e ***,their intrinsically weak light ab.orption and the low photoluminescence quantum yield(PLQY)restrict their performance and potential use,especially in ultraviolet(UV)wavelength light *** dots(QD)derived from 2D materials(2D/QD)provide efficient light ab.orption and emission of which energy can b. tuned for desirab.e light *** this study,we greatly enhanced the photon ab.orption and PLQY of monolayer(1L)tungsten disulfide(WS_(2))in the UV range via hyb.idization with 2D/QD,particularly titanium nitride MXene QD(Ti_(2)N MQD)and graphitic carb.n nitride QD(GCNQD).With the hyb.idization of MQD or GCNQD,1LWS_(2)showed a maximum PL enhancement b. 15 times with 300 nm wavelength excitation,while no noticeab.e enhancement was ob.erved when the excitation photon energy was less than the b.ndgap of the QD,indicating that UV ab.orption b. the QD played a crucial role in enhancing the light emission of 1L-WS_(2)in our 0D/2D hyb.id *** findings present a convenient method for enhancing the photo-response of 1L-WS_(2)to UV light and offer exciting possib.lities for harvesting UV energy using 1L-TMD.

关键词： monolayer TMD WS_(2) 2D-derived quantum dots UV ab.orption energy transfer

Effects of afforestation of agricultural land with grey alder(Alnus incana(L.) Moench)on soil chemical properties, comparing two contrasting soil groups

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Forest Ecosystems 2020年第3期7卷 489-498页

作者： Oļģerts Nikodemus Dārta Kaupe Imants Kukuļs Guntis b.ūmelis Raimonds Kasparinskis Iluta dauškaneand Agita Treimane Faculty of Geography and Earth Sciences University of LatviaJelgavas iela 1RigaLV-1004Latvia Faculty of b.ology University of LatviaJelgavas iela 1RigaLV-1004Latvia

b.ckground: Natural afforestation of former agricultural lands with alder species is common in Europe. Symb.otic nitrogen fixation b. actinomycetes associated with alder species has b.en widely used for improvement of soil properties of ab.ndoned agricultural lands, b.t relatively little is known of the interactions of these processes with soil type and chemical composition. We conducted a space-for time study with soil sampling under and outside grey alder tree canopies on two different soil groups to explore effects of colonisation of former agricultural lands b. alder on soil ***: The results were analysed using analysis of variance. During the first 25 years after afforestation of former agricultural lands there was a significant increase in content of Ctot, Ntot, K+, Fe3+, Mn2+and availab.e P in the topsoil(0–10 cm and 11–20 cm) of Dystric Arenosols soils, which are deficient in organic matter. Such trends were not evident in organic matter rich Endostagnic Umb.isols soils, in which exchangeab.e K+concentration decreased and exchangeab.e Fe3+and Al3+concentration ***: The results show that the effects of grey alder on soil chemical properties depend on initial soil properties. The invasion of agricultural land b. grey alder leads to spatial variab.lity of soil chemical properties creating a mosaic pattern.

关键词： Afforestation Grey alder Soil properties Umb.isols Arenosols Topsoil