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Propulsion and Power Research 2024年第1期13卷 1-11页

作者： n.I.Cherkashina V.I.Pavlenko m.m.mikhailov A.n.Lapin S.A.yuriev R.V.Sidelnikov D.S.Romanyuk Belgorod State Technological University named after V.G.Shoukhov Kostyukov Str.46Belgorod 308012Russia Tomsk State University of Control Systems and Radioelectronics 40Prospect LeninaTomsk 634050Russia

This paper presents the results of studying the surface properties changes of a ther-moregulating coating based on polystyrene and silicaﬁller after proton irradiation with an en-ergy of 50 keV at afluence of 3�1015 cm�*** proton irradiation,the values of the contact angle of wetting with water increase by 3.5%and 14.9%for polystyrene and the coating,*** free surface energy(energy of the surface layer)of polystyrene and the coat-ings before and after proton irradiation was calculated using the Owens-Wendt-Rabel-Kaelble *** was a signiﬁcant increase in the polarity of the polystyrene surface(gp increased by a factor of 2.2)after proton *** the coating,an increase in gp by a factor of 3.89 was observed after proton *** changes in the coating were presented by IR Fourier spectroscopy.A slight decrease in the absorption intensity of all characteristic bands compared to the unirradiated sample was *** was found that the irradiation of the coating with protons led to the formation of macromolecules with hydroxyl,carbonyl,and carboxyl bonds,as well as the formation of dimeric and oligomeric siloxane *** was also found that after irradiation of a pure polystyrene sample with protons,the value of the solar absorption as increased by only 4.2%;whereas for the coating with silicaﬁller,the value of as increased by 28.6%.

关键词： Thermal control coating Proton irradiation Hydrophobicity Free surface energy Radiation crosslinking

Thermal performance of domed roof in air-conditioned spaces

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Energy and Built Environment 2024年第2期5卷 270-287页

作者： Ibrahim Reda Raouf n.Abdelmessih mohamed Steit Ehab m.mina mechanical Power Engineering Faculty of EngineeringAin Shams University1 El-Sarayat St.Cairo 11517Egypt Architectural Engineering Faculty of EngineeringAin Shams UniversityCairoEgypt

Due to their thermal performance,domed roofs are one of the passive solutions that affect energy consumption in *** thermal performance of domed roofs has been investigated in many naturally ventilated ***,few studies have discussed their performance in conditioned ***,this study introduces a computational comparison between domed and flat roofs to investigate their impact on thermal comfort inside a conditioned *** an earlier stage,field measurements were carried out inside a Bahraini mosque to acquire its indoor air conditions during the summer period of 2021,in addition to validating the computational *** findings of this study confirm that,under mechanical cooling conditions,the flat roof offers a lower indoor temperature than the domed roof by 0.4℃and 0.1℃for open and closed doors,***,the air velocity is lower by approximately 0.01 m/s for both door *** overall PmV values of the flat roof are also lower by 0.07 and 0.01,while the PPD values are lower by 0.20,and 0.34 for open and closed doors,*** on these small differences,it can be concluded that the thermal performance of both roofing systems behaves equally in conditioned ***,the air patterns are substantially different,the overall thermal performance is *** similarity drives building designers to rethink the thermal performance of the domed roofs in air-conditioned spaces with such a hot climate,regardless of their aesthetic and acoustical behaviour.

关键词： Thermal comfort Computational fluid dynamics(CFD) Predicted mean vote(PmV)and predicted percentage dissatisfied(PPD) Domed roof Flat roof

Biosynthesized CS-mgO/zeolite hybrid material:An efficient adsorbent for chlorpyrifos removal-Kinetic studies and response surface methodology

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Emerging Contaminants 2024年第3期10卷 304-317页

作者： mohammed T.m.H.Hamad Belal n.A.mahran Central Laboratory for Environmental Quality monitoring National Water Research CenterEgypt

The prevalence of organophosphate pesticides in aquatic environments raises severe concerns on a global ***,an insecticide,is included in a class of organophosphate *** is widely used on agricultural lands to control pests in cotton,fruit,and *** acute toxicity of chlorpyrifos is still dangerous to all aquatic living *** the treatment of water contaminated with chlorpyrifos is an important *** recent decade has witnessed adsorption technology emerging as an advanced organophosphate pesticide wastewater treatment with great potential and a grand blueprint,in which the specific surface area and active sites of the adsorbent are considered to be the two most important characteristics largely impacting the adsorption *** this study,a CS-mgO/Zeolite composite was prepared by the microbial method as an effective adsorbent for the removal of chlorpyrifos from an aqueous *** adsorbent's properties were carefully characterized using Xray diffraction,scanning electron microscopy,and Fourier-transform infrared *** refinement of experimental conditions,encompassing variations in adsorbent dosage,contact time,and chlorpyrifos concentration at five discrete levels,was systematically undertaken through the utilization of a composite central design rooted in response surface *** solution pH played a key role in chlorpyrifos removal,and a pH of 7.0 was selected according to its high adsorption *** highest removal(80.9%)of chlorpyrifos by CS-mgO/Zeolite was obtained at an optimum pH of 7,a contact time of 40 min,an adsorbent dosage of 0.4 g/L,and a chlorpyrifos concentration of 5 mg/L^(-1).The adsorption results were highly fitted with the Freundlich adsorption isotherm model,and the maximum adsorption was 83.3 mg/*** studies indicate that the removal of chlorpyrifos followed the pseudo-secondorder model of adsorption(0.994).The thermodynamic parameters indicate the sponta

关键词： Chlorpyrifos adsorption CS-mgO/Zeolite Response surface methodology

Dust particle surface potential in an argonhelium plasma using the(r,q)-distribution function

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Communications in Theoretical Physics 2024年第9期76卷 141-148页

作者： Bahaaudin m Raffah A A Abid Abdullah Khan Amin Esmaeili yas Al-Hadeethi m n S Qureshi Department of Physics Faculty of SciencesKing Abdulaziz UniversityJeddah 21589Saudi Arabia Lithography in Devices Fabrication and Development Research Group Deanship of Scientific ResearchKing Abdulaziz UniversityJeddah 21589Saudi Arabia Joint Laboratory of Plasma Application Technology Institute of Advanced TechnologyUniversity of Science and Technology of ChinaHefei230026China CAS Key Laboratory of Geospace Environment University of Science and Technology of ChinaHefei230026China Department of Physics Zhejiang Normal UniversityJinhua321005China Department of Physics Graduate School of ScienceTokyo Metropolitan UniversityMinami-Osawa 1-1Hachioji City192-0397Japan Department of Physics GC UniversityLahore 54000Pakistan

In this paper,the dust particle surface potential for argon-helium plasma is evaluated analytically and numerically in the context of negatively charged dust particles by employing a power-law(r,q)-distribution *** studies have reported the argon-helium plasma and conducted a brief theoretical and experimental *** deepen our understanding further,this study aims to analyze the argon-helium plasma comprehensively using the same pattern but with the(r,q)-distribution *** this purpose,the current balance equations are derived for electron,helium and argon ions,when these charge species attain the quasineutrality *** numerically examined the currents of plasma species for a broad range of effective distribution function parameters r and *** is revealed that the surface potential of dust particles is significantly affected by the parameters r and q,helium ion-to-electron temperature ratio,argon ion-to-electron temperature ratio,and helium ion to argon ion number density *** incorporating the multi-ion(argon-helium)species,the significance of low-temperature nonmaxwellian dusty(complex)plasma is briefly examined.

关键词： dusty plasma dust charge potential plasma physics helium argon plasma r q distribution function non-maxwellian distribution

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On thermoelastic problem based on four theories with the efficiency of the magnetic field and gravity

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Journal of Ocean Engineering and Science 2024年第4期9卷 338-347页

作者： A.A.Kilany A.n.Abd-alla A.m.Abd-Alla S.m.Abo-Dahab Department of mathematics Faculty of ScienceSohag UniversitySohag 82524 Egypt Department of Computer Science Faculty of Computers and InformationLuxor UniversityEgypt Department of mathematics Faculty of ScienceSouth Valley UniversityQena 83523Egypt

The fundamental objective of this paper is to study the effectiveness of magnetic field and gravity on an isotropic homogeneous thermoelastic structure based on four theories of generalized *** another meaning,the models of coupled dynamic theory(CDT),Lord-Shulman(LS),Green-Lindsay(GL)as well as Green-naghdi(Gn II)will be taken in the ***,applying the harmonic method(normal mode technique),the solution of the governing equations and the expressions for the components of the displacement,temperature and(mechanical and maxwell’s)stresses is taken into account and calculated *** impacts of the gravity and magnetic field are illustrated graphically which are pronounced on the different physical ***,the results of some research that others have previously obtained may be found some or all of them as special cases from this study.

关键词： Generalized thermoelasticity Gravity magnetic field Green and naghdi TheoryⅡ normal mode approach

Long-term monitoring reveals the effect of precipitation and silviculture on nothofagus regeneration in northern Patagonia mixed forests

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Ecological Processes 2024年第2期13卷 103-117页

作者： Georgina Sola Camila mateo Alejandro Dezzotti Paula marchelli Hernán Attis Beltrán Renato Sbrancia Luis Chauchard marcelo González Pe?alba martín Lara Verónica El mujtar Consejo nacional de Investigaciones Científicas y Técnicas (COnICET ) Asentamiento Universitario San martín de los Andes (AUSmA-UnCo) Instituto de Investigaciones Forestales y Agropecuarias Bariloche (IFAB) Instituto Nacional de Tecnología Agropecuaria (INTA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Departamento de Conservación y manejo Parque Nacional Lanín- Administración de Parques Nacionales (PNL-APN)

Background Tree regeneration is a key component of resilience because it promotes post-disturbance recovery of forests. northwestern Patagonia from Argentina is occupied by nothofagus alpina（na）, n. obliqua（no）, and n. dombeyi（nd） forests that grow along an intense precipitation gradient, managed throughout shelterwood silvicultural system by technicians of the Lanin natural Reserve. The objective of this study was to evaluate the influence of seeding cuttings over the dynamics of nothofagus mixed forests across landscape（precipitation gradient） based mainly on the composition and abundance of tree regeneration, permanent sampling plots and generalized linear mixed models. In particular, we analysed:（i） the structure of sexual and asexual regeneration during nd > 20 years after harvest（the dynamics of managed forests）, and（ii） the structure of sexual regeneration in primary and managed forests after > 20 years of harvest（the effect of silviculture）.Results nd was the most abundant species in the regeneration of managed forests during all periods in both sites despite its lower contribution to the adult cohort. During the 10–20 years period after harvest, the humid site exhibited higher regeneration density than the mesic site(120,000 and 6000 ind ha-1, respectively), and it decreased afterwards. The number of established regeneration（> 2 m height） was lower for na in the mesic site and for no in the humid site(0 and 57 ind ha-1, respectively). However, in comparison to no, na showed a higher number of sprouted stumps and sprouts per stump, and a higher sprout height in the mesic site. no exhibited higher sprout mortality in the humid site. Finally, the regeneration of primary forests showed lower density and height, and a more balanced composition than that of managed *** The silvicultural effects on the mixed forest regeneration dynamics was strongly influenced by the condition of sites. Therefore, management prescriptions should be adj

关键词： nothofagus alpina nothofagus obliqua nothofagus dombeyi Basal sprouting Shelterwood silvicultural system Ecological resilience

Fuel cell stack design and modelling with a double-stage boost converter coupled to a single-phase inverter

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Clean Energy 2024年第1期8卷 188-196页

作者： Basem E.Elnagi Ahmed m.Ismaiel Hany S.E.mansour m.n.Abd-Alwahab Electrical Engineering Department Faculty of EngineeringSuez Canal UniversityIsmailia 41522Egypt

A comprehensive proton-exchange membrane fuel cell stack model was developed and integrated with a two-stage DC/DC boost *** was directly coupled to a single-phase(two levels-four pulses)inverter without a *** pulse-width modu-lation signal was used to independently regulate every converter *** converter was modelled using a mATLAB®/Simulink®environment and an appropriate voltage control *** analysis features of the suggested circuit were created and,through established experiments,the simulation results were verified.A single-phase(two levels-four pulses)inverter control circuit was tested and it produced a pure sinusoidal waveform with voltage *** matches the voltage of the network in terms of amplitude and frequency.A sinusoidal pulse-width modulation approach was performed using a single-phase(two levels-four pulses)pulse-width modulation *** results demonstrated an enhancement in the standard of the output wave and tuned the dead time with a reduction of 63μs compared with 180μs in conventional techniques.

关键词： PEm fuel cell pulse-width modulation single-phase inverter and double-stage DC/DC boost converter

Soil organic carbon stocks in native forest of Argentina:a useful surrogate for mitigation and conservation planning under climate variability

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Ecological Processes 2024年第1期13卷 3-24页

作者： Pablo L.Peri Juan Gaitán matías mastrangelo marcelo nosetto Pablo E.Villagra Ezequiel Balducci martín Pinazo Roxana P.Eclesia Alejandra Von Wallis Sebastián Villarino Francisco Alaggia marina González Polo Silvina manrique Pablo A.meglioli Julián Rodríguez-Souilla martín mónaco Jimena E.Chaves Ariel medina Ignacio Gasparri Eugenio Alvarez Arnesi maría Paula Barral Axel von müller norberto m.Pahr Josefina Uribe Echevarria Pedro Fernández marina morsucci Dardo López Juan manuel Cellini Leandro Alvarez Ignacio Barberis Hernán Colomb Ludmila La manna Sebastián Barbaro Cecilia Blundo Ximena Sirimarco Laura Cavallero Gualberto Zalazar Guillermo martínez Pastur Instituto nacional de Tecnología Agropecuaria (InTA) Universidad nacional de la Patagonia Austral (UnPA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Universidad nacional de Luján Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Grupo de Estudio de Agroecosistemas y Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET ) CCT San Luis Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto Argentino de nivología Glaciología y Ciencias Ambientales (IANIGLA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Universidad Nacional de Cuyo Instituto de Investigaciones en Biodiversidad y medioambiente (InIBIOmA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto de Investigaciones en Energía no Convencional CCT Salta-JujuyConsejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de Recursos Agroforestales Centro Austral de Investigaciones Científicas (CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Dirección nacional de Bosques Ministerio de Ambiente y Desarrollo Sostenible de la Nación Instituto de Ecología Regional Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )Universidad Nacional de Tucumán Universidad nacional de Rosario Instituto de Investigaciones en Ciencias Agrarias de Rosario Centro Científico Tecnológico CONICET Grupo de Estudio de Agroecosistemas y Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de Investigaciones en maderas (LImAD) Universidad Nacional de La Plata (UNLP) Administración de Parques nacionales (APn) Parque Nacional Los Alerces Centro de Estudios Ambientales Integrados (CEAI) Universidad Nacional de la Patagonia San Juan Bosco (UNPASJB) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )

Background The nationally determined contribution（nDC） presented by Argentina within the framework of the Paris Agreement is aligned with the decisions made in the context of the United nations Framework Conven-tion on Climate Change（UnFCCC） on the reduction of emissions derived from deforestation and forest degradation, as well as forest carbon conservation（REDD+）. In addition, climate change constitutes one of the greatest threats to forest biodiversity and ecosystem services. However, the soil organic carbon（SOC） stocks of native forests have not been incorporated into the Forest Reference Emission Levels calculations and for conservation planning under cli-mate variability due to a lack of information. The objectives of this study were:（i） to model SOC stocks to 30 cm of native forests at a national scale using climatic, topographic and vegetation as predictor variables, and（ii） to relate SOC stocks with spatial–temporal remotely sensed indices to determine biodiversity conservation concerns due to threats from high inter-annual climate *** We used 1040 forest soil samples（0–30 cm） to generate spatially explicit estimates of SOC native forests in Argentina at a spatial resolution of approximately 200 m. We selected 52 potential predictive environmental covari-ates, which represent key factors for the spatial distribution of SOC. All covariate maps were uploaded to the Google Earth Engine cloud-based computing platform for subsequent modelling. To determine the biodiversity threats from high inter-annual climate variability, we employed the spatial–temporal satellite-derived indices based on Enhanced Vegetation Index（EVI） and land surface temperature（LST） images from Landsat *** SOC model（0–30 cm depth） prediction accounted for 69% of the variation of this soil property across the whole native forest coverage in Argentina. Total mean SOC stock reached 2.81 Pg C（2.71–2.84 Pg C with a probability of 90%） for a total area of 460,790 km2,

关键词： Soil organic carbon Biodiversity native forest Climate change mitigation modelling Resilience

A folic acid-decorated nanoparticles loaded JQ1 for oral squamous cell carcinoma therapy

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Chinese Chemical Letters 2024年第3期35卷 332-336页

作者： Dequan Zeng Zhongkai ma Xin zan Ting Luo Xiang Wang Xiang Gao Xianghui Fu School of Health management Xihua UniversityChengdu 610039China State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesWest China College of StomatologySichuan UniversityChengdu 610041China Department of neurosurgery and Institute of neurosurgery State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalWest China Medical SchoolSichuan University and Collaborative Innovation Center for BiotherapyChengdu 610041China Breast Disease Center Cancer CenterWest China HospitalSichuan UniversityChengdu 610041China

Oral squamous cell carcinoma(OSCC)is known as one of the most malignant tumors with high recurrence and fatality *** poor tumor-targeting ability of traditional chemotherapeutic drugs has been a grand challenge for anti-OSCC *** that,a large quantity of tumor associated macrophages in OSCC tissues further diminish the anti-tumor effects of these ***,we produced a therapeutic nano drug delivery system(FA-PEG-PLA-JQ1)through encapsulating JQ1[a small-molecule inhibitor of bromodomain containing protein 4(BRD4)]into the folic acid(FA)-modified nanoparticle(PEG-PLA),which could prolong the half-life of JQ1 and target the tumor *** then,JQ1 released from this nanoparticle could prevent OSCC growth inducing tumor cell apoptosis,inhibiting tumor angiogenesis and the polarization of m2 type *** conclusion,our date demonstrated the therapeutic benefits of FA-PEG-PLA-JQ1 against OSCC in vivo or in vitro,which could be a novel treatment strategy for OSCC in coming days.

关键词： Folic acid nanoparticles JQ1 Oral squamous cell carcinoma macrophages

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The effectiveness of different wear indicators in quantifying wear on railway wheels of freight wagons

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Railway Engineering Science 2024年第3期32卷 307-323页

作者： Philipe Augusto de Paula Pacheco m.magelli matheus Valente Lopes Pedro Henrique Alves Correa n.Zampieri n.Bosso Auteliano Antunes dos Santos Federal Institute of the Southeast of minas Gerais(IF Sudeste mG) Técnico PanamáStreet 45Santos DumontMG 36246-311Brazil Railway Laboratory(Lafer) Universidade Estadual de Campinas(UNICAMP)Mendeleyev Street 200CampinasSP 13083-872Brazil Department of mechanical and Aerospace Engineering Politecnico Di TorinoC.so Duca degli Abruzzi 2410129 TurinItaly

Railway infrastructure relies on the dynamic interaction between wheels and rails;thus,assessing wheel wear is a critical aspect of maintenance and *** paper focuses on the wheel-rail wear indicator T-gamma(Tγ).Amidst its use,it becomes apparent that Tγ,while valuable,fails to provide a comprehensive reflection of the actual material removal and actual contact format,which means that using only Tγas a target for optimization of profiles is not *** this work,three different freight wagons are evaluated:a meter-gauge and a broad-gauge heavy haul vehicles from South American railways,and a standard-gauge freight vehicle operated in Europe,with different axle loads and dissimilar new wheel/rail *** vehicles are subjected to comprehensive multibody simulations on various *** simulations aimed to elucidate the intricate relationship between different wear indicators:Tγ,wear index,material removal,and maximum wear depth,under diverse curves,non-compensated lateral accelerations(A_(nc)),and *** findings showed a correlation of 0.96 between Tγand wear depth and 0.82 between wear index and material removed for the outer *** the results,the Tγis better than the wear index to be used when analyzing wear depth while the wear index is more suited to foresee the material *** results also show the low influence of A_(nc)on wear index and Tγ.By considering these factors together,the study aims to improve the understanding of wheel-rail wear by selecting the best wear analysis approaches based on the effectiveness of each parameter.

关键词： Wear index Wear volume Wear modeling Dynamic simulation

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