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Journal of Wuhan University of Technology(Materials Science) 2005年第B12期20卷 7-9页

作者： Esenwein Stefan A Bogdanski Denise Prymak Oleg Epple Matthias Muhr Gert kller manfred Department of Surgery BG Trauma Center Bergmannsheil University Hospital Buerkle-de-la-Camp-Platz 1 D-44789 Bochum Germany Department for Surgical Research BG Trauma Center Bergmannsheil Ruhr-University Bochum Buerkle-de-la-Camp-Platz 1 D-44789 Bochum Germany Institute for Inorganic Chemistry University of Duisburg-Essen Universitaetsstr. 5-7 D-45117 Essen Germany

The influence of different surface coatings of NiTi shape memory allays was examined using in vitro testing methods. Plates of superelastic nickel-titanium shape memory allay （ NiTi ） were coated with calcium phosphates （ hydroxyapatite ） by high-temperature plasma-spraying or by dip-coating. The biocompatibility was tested in vitro by cultivation of isolated human granulocytes and whole blood cells. As substrates, pure NiTi, plasma-spray-coated NiTi and dip-coated NiTi were used. Isolated granulocytes showed an increased adhesion to both calcium phosphate-coated NiTi samples. Compared to non-coated NiTi or dip-coated NiTi, the number of dead granulocytes adherent to plasma-sprayed surfaces was significantly increased （ p 〈 0.01 ）. Whether the d/f- ferences in apoptosis of granulocytes on dip-coated vs plasma-sprayed coatings observed are due to differences in material surface morphologies has to be analyzed in further studies. Because of the cellular interactions with the coating layers, h is likely that the results obtained are not caused by the underlying NiTi but due to the coating itself.

关键词： shape memory alloys nitinol biomaterials testing calcium phosphate coating biocompatibility surface coating implant testing

Identifying suitable areas for plenter forest management

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FOREST ECOSYSTEMS 2025年第1期12卷 83-92页

作者： Leiter, Mathias Pucher, Christoph kessler, Michael Hoeuronigsberger, Ferdinand Lexer, manfred J. Vacik, Harald Hasenauer, Hubert Univ Nat Resources & Life Sci BOkU Inst Silviculture Peter Jordan Str 82 A-1190 Vienna Austria Univ Nat Resources & Life Sci BOkU Inst Forest Engn Peter Jordan Str 82 A-1190 Vienna Austria

关键词： Plenter forest Uneven-aged forest management Tree species suitability Tree harvesting Transformation

Spherical quantum dot described by a scalar exponential potential under the influence of a linear electric field

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Communications in Theoretical Physics 2025年第2期77卷 172-175页

作者： k Bakke Departamento de Física Universidade Federal da Paraíba

We study the confinement of a spinless charged particle to a spherical quantum dot under the influence of a linear electric field. The spherical quantum dot is described by a short-range potential given by the power-exponential potential. Then, by analysing the region near the spherical quantum dot centre, we discuss two cases where the energy levels can be obtained for s-waves and how the linear electric field modifies the spectrum of energy of the spherical quantum dot.

关键词： spherical quantum dot power-exponential potential short-range potential linear electric field

Regression analysis of squeezing-induced hybrid nanofluid flow in Darcy-Forchheimer porous medium

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 193-208页

作者： k.MUHAMMAD M.SARFRAZ Department of Humanities and Sciences School of Electrical Engineering and Computer Science National University of Sciences and Technology Department of Mathematics Quaid-i-Azam University

This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing velocity. The space between these plates contains a Darcy-Forchheimer porous medium. A mixture of water-based fluid with gold(Au) and silicon dioxide(Si O2) nanoparticles is formulated. In contrast to the conventional Fourier's heat flux equation, this study employs the Cattaneo-Christov heat flux equation. A uniform magnetic field is applied perpendicular to the flow direction, invoking magnetohydrodynamic(MHD) effects. Further, the model accounts for Joule heating, which is the heat generated when an electric current passes through the fluid. The problem is solved via NDSolve in MATHEMATICA. Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow, energy transport, and skin *** findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies. It is observed that the squeezing motion generates additional pressure gradients within the fluid, which enhances the flow rate but reduces the frictional drag. Consequently, the fluid is pushed more vigorously between the plates, increasing the flow velocity. As the fluid experiences higher flow rates due to the increased squeezing effect, it spends less time in the region between the plates. The thermal relaxation, however, abruptly changes the temperature, leading to a decrease in the temperature fluctuations.

关键词： convective boundary condition Darcy-Forchheimer medium hybrid nanofluid Joule heating magnetohydrodynamic (MHD) numerical solution O175.2 O361 regression analysis squeezing flow

An illustrated guide to:Distributed and integrated fibreoptic sensing in seismology

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Earthquake Science 2025年第1期38卷 67-77页

作者： Andreas Fichtner Fabian Walter Patrick Paitz Sara klaasen Daniel C.Bowden Sebastian Noe Nils Müller Dominik Husmann Jacques Morel Department of Earth Sciences ETH ZürichZürich 8049Switzerland Swiss Federal Institute for Forest Snow and Landscape ResearchBirmensdorf 8903Switzerland Swiss Federal Institute of Metrology METAS Bern 3003Switzerland

The properties of laser signals are affected by deformation of the optical fibre through which they are *** this deformation dependence is undesirable in telecommunication,it can be exploited for the construction of novel seismic sensors that fill a niche in data acquisition where traditional seismometer arrays would be difficult to *** includes densely populated urban centers,the oceans,volcanoes and the Earth’s polar *** notes complement a presentation on recent methodological developments and applications in fibre-optic *** first part is focused on the use of distributed fibreoptic sensing in cryosphere research,and specifically the investigation of the internal structure and seismicity of glaciers and ice *** second part is dedicated to recent advances in integrated fibre-optic sensing,with emphasis on novel measurement principles and sensitivity.

关键词： seismology fibre-optics cryosphere earthquakes

Photoluminescence upgradation of La_(2)MgTiO_(6):2%Dy^(3+) perovskite with monovalent(Li^(+)),divalent(Ba^(2+),Sr^(2+)) and trivalent(Bi^(3+),Sm^(3+))cation sensitization

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Journal of Rare Earths 2025年第1期43卷 47-56,I0002页

作者： V.P.Veena k.Arun C.k.Shilpa S.V.Jasira k.M.Nissamudeen School of Pure and Applied Physics Kannur UniversityPayyanur CampusEdatKannurKrala67 India Department of Nanoscience and Nanotechnology Kannur UniversityPayyanur CampusEdatkannurKerala670327India

Nano phosphors of 2%Dy^(3+)(wt%)doped La_(2)MgTiO_(6) and monovalent/divalent/trivalent co-doped La_(1.98)Dy_(0.02)MgTiO_(6):x%A^(y+)(A^(y+):Li+,Ba^(2+),Sr^(2+),Bi^(3+),and Sm^(3+);0≤x≤2 wt%)were synthesized by combustion *** the XRD data,it is deduced that an increase in the valency of co-dopant increases the crystallinity of the double perovskite orthorhombic nanocrystal *** an increase in co-dopant size,an elevation in optical bandgap is visible with the highest bandgap of 3.835 eV for Bi^(3+).The photo-absorption is monotonically broadened for Sr^(2+),Sm^(3+),and Li+around 200-450 ***351 nm,Dy^(3+)triggered lattice shows major characteristic emission peaks at 480 nm(^(4)F_(9/2)→^(6)H_(15/2)),574 nm(^(4)F_(9/2)→^(6)H_(13/2)),and 670 nm(^(4)F_(9/2)→^(6)H_(11/2)).leading to near white light emission with CIE coordinates(0.341,0.376).Upon co-doping,the PL intensity is significantly increased with maximum emission for trivalent Sm^(3+),followed by divalent Sr^(2+)and monovalent Li+*** increasing excitation wavelength,Sr^(2+)shows a dominated output and it is found that divalent Sr^(2+)is a potential codopant that could enhance luminescence intensity up to 6 times with a Sr^(2+)→Dy^(3+)energy transfer efficiency of 86%.It is specified that the CIE coordinates of Li+co-doped samples show ideal white emission with color coordinates(0.333,0.336).The concluding outcomes signify the noblest rare earth Sm^(3+)co-doping and thus Sm^(3+)→Dy^(3+)energy transfer mechanism is discussed in detail.

关键词： Photoluminescence Perovskite WLED Co-doping Rareearths

Identifying suitable areas for plenter forest management

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Forest Ecosystems 2025年第01期 83-92页

作者： Mathias Leiter Christoph Pucher Michael kessler Ferdinand H?nigsberger manfred J.Lexer Harald Vacik Hubert Hasenauer Institute of Silviculture University of Natural Resources and Life Sciences (BOKU) Institute of Forest Engineering University of Natural Resources and Life Sciences (BOKU)

Plenter forests, also known as uneven-aged or continuous cover forests enhance forest resilience and resistance against disturbances compared to even-aged forests. They are considered as an adaptation option to mitigate climate change effects. In this study, we present a conceptual approach to determine the potentially suitable area for plenter forest management within central European mixed species forests and apply our approach to the case study area in Styria, the south-eastern Province of Austria. The concept is based on ecological and technicaleconomic constraints and considers expected future climate conditions and its impact on plenter forest management. For each 1 ha forest pixel, we assess the ecological conditions for plenter forest management according to the autecological growth conditions of silver fir, and at least one additional shade tolerant tree species. The technical-economic constraints are defined by slope(≤30%) and distance to the next forest road(≤100 m) to ensure cost-efficient harvesting. The results show that under current climate conditions 28.1% or 305,349 ha of the forests in Styria are potentially suitable for plenter forest management. For the years 2071–2100 and under the climate change scenario RCP 4.5, the potential area decreases to 286,098 ha(26.3% of the total forest area)and for the scenario RCP 8.5 to 208,421 ha(19.1% of the total forest area). The main reason for these changes is the unfavourable growing conditions for silver fir in the lowlands, while in the higher elevations silver fir is likely to expand. Our results may serve forest managers to identify areas suitable for plenter forests and assist in the transformation of even-aged pure forests to uneven-aged forests to increase resistance, resilience, and biodiversity under climate change.

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Honeycomb-spiderweb-inspired self-similar hybrid cellular structures for impact applications

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Defence Technology(防务技术) 2025年第1期43卷 182-200页

作者： k.Tewari M.k.Pandit M.M.Mahapatra P.R.Budarapu School of Mechanical Sciences Indian Institute of Technology BhubaneswarBhubaneswar752050India

Inspired by nature's self-similar designs,novel honeycomb-spiderweb based self-similar hybrid cellular structures are proposed here for efficient energy absorption in impact *** energy absorption is enhanced by optimizing the geometry and topology for a given *** proposed hybrid cellular structure is arrived after a thorough analysis of topologically enhanced self-similar *** optimized cell designs are rigorously tested considering dynamic loads involving crush and high-velocity bullet ***,the influence of thickness,radial connectivity,and order of patterning at the unit cell level are also *** maximum crushing efficiency attained is found to be more than 95%,which is significantly higher than most existing traditional *** on,the first and second-order hierarchical self-similar unit cell designs developed during crush analysis are used to prepare the cores for sandwich *** tests are performed on the developed sandwich structures using the standard 9-mm *** influence of multistaging on impact resistance is also investigated by maintaining a constant total thickness and mass of the sandwich ***,in order to avoid layer-wise weak zones and hence,attain a uniform out-of-plane impact strength,off-setting the designs in each stage is *** sandwich structures with first and second-order self-similar hybrid cores are observed to withstand impact velocities as high as 170 m/s and 270 m/s,respectively.

关键词： Sandwich structures Honeycomb-spider web inspired Self-similar hierarchy Crush analysis High-velocity impact Strong and weak zones Multistaging

Characterization and source apportionment of volatile organic compounds in Hong kong:A 5-year study for three different archetypical sites

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Journal of Environmental Sciences 2025年第5期151卷 424-440页

作者： Yuchen Mai Vincent Cheung Peter k.k.Louie kenneth Leung Jimmy C.H.Fung Alexis k.H.Lau Donald R.B.lake Dasa Gu Division of Environment and Sustainability The Hong Kong University of Science and TechnologyHong Kong 999077China Environmental Protection Department Hong Kong 999077China Environment and Ecology Bureau Hong Kong 999077China Department of Chemistry University of CaliforniaIrvine 92617USA

Initial success has been achieved in Hong kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three *** organic compounds(VOCs)are important for mitigating ozone pollution as its major *** study analyzed VOC characteristics of roadside,suburban,and rural sites in Hong kong to investigate their compositions,concentrations,and source *** showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,*** using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and OH reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and OH reactivity at the suburban and rural sites,*** findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas.

关键词： Volatile organic compounds Positive matrix factorization Source apportionment Ozone formation

Intrumer:A Multi Module Distributed Explainable IDS/IPS for Securing Cloud Environment

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Computers, Materials & Continua 2025年第1期82卷 579-607页

作者： Nazreen Banu A S.k.B.Sangeetha Department of Computer Science and Engineering SRM Institute of Science and TechnologyVadapalani CampusChennai600026Tamil NaduIndia

The increasing use of cloud-based devices has reached the critical point of cybersecurity and unwanted network *** environments pose significant challenges in maintaining privacy and *** approaches,such as IDS,have been developed to tackle these ***,most conventional Intrusion Detection System(IDS)models struggle with unseen cyberattacks and complex high-dimensional *** fact,this paper introduces the idea of a novel distributed explainable and heterogeneous transformer-based intrusion detection system,named INTRUMER,which offers balanced accuracy,reliability,and security in cloud settings bymultiplemodulesworking together within *** traffic captured from cloud devices is first passed to the TC&TM module in which the Falcon Optimization Algorithm optimizes the feature selection process,and Naie Bayes algorithm performs the classification of *** selected features are classified further and are forwarded to the Heterogeneous Attention Transformer(HAT)*** this module,the contextual interactions of the network traffic are taken into account to classify them as normal or malicious *** classified results are further analyzed by the Explainable Prevention Module(XPM)to ensure trustworthiness by providing interpretable *** the explanations fromthe classifier,emergency alarms are transmitted to nearby IDSmodules,servers,and underlying cloud devices for the enhancement of preventive *** experiments on benchmark IDS datasets CICIDS 2017,Honeypots,and NSL-kDD were conducted to demonstrate the efficiency of the INTRUMER model in detecting network trafficwith high accuracy for different *** outperforms state-of-the-art approaches,obtaining better performance metrics:98.7%accuracy,97.5%precision,96.3%recall,and 97.8%*** results validate the robustness and effectiveness of INTRUMER in securing diverse cloud environments against sophisticated cyber threats.

关键词： Cloud computing intrusion detection system transformers and explainable artificial intelligence(XAI)