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Transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 177-192页

作者： m.NAVEED m.ImRAN T.ASGHAR z.ABBAS Department of mathematics Division of Science and TechnologyUniversity of Education Department of mathematics The Islamia University of Bahawalpur

This paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. The influence of magnetic fields is also inspected in terms of their physical characteristics. To depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAm).The effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

关键词： hybrid nanofluid oscillating curved stretchable sheet gyrotactic microorganism Cattaneo-Christov heat and mass flux chemical reaction analytical solution O368

Impact of ocean data assimilation on the seasonal forecast of the 2014/15 marine heatwave in the Northeast Pacific Ocean

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 24-31页

作者： Tiantian tang Jiaying He Huihang Sun Jingjia Luo Institute for Climate and Application Research(ICAR)/Key Laboratory of meteorological Disaster Nanjing University of Information Science and TechnologyNanjingChina

A remarkable marine heatwave,known as the“Blob”,occurred in the Northeast Pacific Ocean from late 2013 to early 2016,which displayed strong warm anomalies extending from the surface to a depth of 300 *** study employed two assimilation schemes based on the global Climate Forecast System of Nanjing University of Information Science(NUIST-CFS 1.0)to investigate the impact of ocean data assimilation on the seasonal prediction of this extreme marine *** sea surface temperature(SST)nudging scheme assimilates SST only,while the deterministic ensemble Kalman filter(EnKF)scheme assimilates observations from the surface to the deep *** latter notably improves the forecasting skill for subsurface temperature anomalies,especially at the depth of 100-300 m(the lower layer),outperforming the SST nudging *** excels in predicting both horizontal and vertical heat transport in the lower layer,contributing to improved forecasts of the lower-layer warming during the *** improvements stem from the assimilation of subsurface observational data,which are important in predicting the upper-ocean *** results suggest that assimilating ocean data with the EnKF scheme significantly enhances the accuracy in predicting subsurface temperature anomalies during the Blob and offers better understanding of its underlying mechanisms.

关键词： Seasonal forecast Ocean data assimilation marine heatwave Subsurface temperature

Infrared, Diffuse Reflectance and Dielectric Studies ofAntimony Trisulphide

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Journal of materials Science & Technology 1998年第4期14卷 344-348页

作者： Hanafi, z.m. Ismail, F.m. Khalil, m.Sh. Inorganic Chemistry Dept. National Research Centre Dokki Cairo Egypt

Infrared absorption spectra of orange, black and transferred Sb//2S//3 samples have been studied in the spectral range 200-4000 cm** minus **1. The pronounced difference between the different samples is the appearance of excess sulphur present in the orange and transferred samples except those of transferred at 543 K and the black Sb//2S//3. The change of sharpness of some IR peaks reveals the amorphous/crystalline change. The effect of the degree of crystallinity and stoichiometry on the energy gap values was investigated by using optical method. The obtained dielectric parameters epsilon prime and epsilon double prime of the different samples are thoroughly affected by the degree of crystallinity and smoothly affected by either the frequency or the temperature or both, except at lower frequencies. (Edited author abstract) 26 Refs.

关键词： Antimony compounds

Residual Strains in a Nanometer Thick Cr Film measured on micromachined Beams

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Journal of materials Science & Technology 2009年第1期25卷 77-80页

作者： z.m. zhou Yong zhou Ying Cao Haiping mao Key Laboratory for Thin Film and microfabrication Technology of ministry of Education Research Institute of Micro/Nano Science and Technology Shanghai Jiao Tong University Shanghai 200030 China

A Cr film with a 75 nm thickness sputtered on a Si substrate was used to fabricate microbridge and microcantilever samples with the mEmS （microelectromechanical system） technique. The profile of the buckled beams was measured by using the interference technique with white light and fitted with a theoretical result. The uniform residual strain in the bridge samples was deduced from the variation of buckling amplitude with the beam length. On the other hand, the gradient residual strain was determined from the deflection profile of the cantilever. The residual uniform and gradient strain in the Cr film are about 4.96×10^-3 and 4.2967×10^-5, respectively.

关键词： Residual Strain microelectromechanical system (mEmS) microbridge microcantilever

mICROSTRUCTURE OF mg-6.4zn-1.1Y ALLOY FABRICATED BY RAPID SOLIDIFICATION AND RECIPROCATING EXTRUSION

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Acta metallurgica Sinica(English Letters) 2008年第1期21卷 30-36页

作者： z.m. zhang C.J. Xu X.F. Guo School of materials Science ＆ Engineering Xi＇an University of Technology Xi＇an 710048 China

In order to explore the methods to prepare high-strength quasicrystal-reinforced magnesium alloys, the flakes of rapidly solidified mg-6.4zn-1.1 Y magnesium alloy with a thickness of 50-60μm were obtained by a melt spinning single-roller device, and the flakes were then processed into rods by reciprocating extrusion and direct extrusion. The microstructure of the alloy was analyzed by optical microscope and SEm, and the constituent phases were identified by XRD. Phase transformation and its onset temperature were determined by differential thermal analyzer （DTA）. The analysis result shows that rapid solidification for *** alloy can inhibit the eutectic reactions, broaden the solid solubility of zn in α-mg solute solution, and impede the formation of mg3 Y2zn3 and mgzn2 compounds, and thus help the icosahedral mg3 Yzn6 quasicrystal formed directly from the melt. The microstructure of the flakes consists of the α-mg solid solution and icosahedral mg3 Yzn6 quasicrystal. Dense rods can be made from the flakes by two-pass reciprocating extrusion and direct extrusion. The interfaces between flakes in the rods can be welded and jointed perfectly. During the reciprocating extrusion and direct extrusion process, more mg3 Yzn6 compounds are precipitated and distributed uniformly, whereas the rods possess fine microstructures inherited from rapidly solidified flakes. The rods contain only two phases： α- magnesium solid solution as matrix and fine icosahedral mg3 Yzn6 quasicrystal which disperses uniformly in the matrix.

关键词： magnesium alloy Rapid solidification Reciprocating extrusion Quasicrystal

mICROSTRUCTURES AND PROPERTIES OF RECIPROCATINGLY EXTRUDED mg-6.4zn-1.1Y ALLOYS

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Acta metallurgica Sinica(English Letters) 2008年第1期21卷 37-42页

作者： z.m. zhang C.J. Xu X.F. Guo School of materials Science ＆ Engineering Xi＇an University of Technology Xi＇an 710048 China

An icosahedral mg3 Yzn6 quasicrystalline phase can be produced in mg-zn- Y system alloys when a proper amount of zn and Y is contained, and it is feasible to prepare the quasicrystal phase-reinforced low-density magnesium alloy. In this article, phase constituents and the effect of reciprocating extrusion on microstructures and properties of the as-cast mg-6.4zn-1.1 Y alloy are analyzed. The microstructure of the as-cast mg-6.4zn-1.1 Y alloy consists of the α-mg solid solution, icosahedral mg3Yzn6 quasicrystal, and mg3 Y2zn3 and mgzn2 compounds. After the alloy was reciprocatingly extruded for four passes, grains were refined, mg3 Y2 zn3 and mgzn2 phases dissolved into the matrix, whereas, mg3 Yzn6 precipitated and distributed uniformly. The alloy possesses the best performance at this state; the tensile strength, yield strength, and elongation are 323.4 mPa, 258.2 mPa, and 19.7%, respectively. In comparison with that of the as-cast alloy, the tensile strength, yield strength, and elongation of the reciprocatingly extruded alloy increase by 258.3%, 397.5%, and 18 times, respectively. It is concluded that reciprocating extrusion can substantially improve the properties of the as-cast mg-6.4zn-1.1 Y alloy, particularly for elongation. The high performance of the mg-6.4zn-1.1 Y alloy after reciprocating extrusion can be attributed to dispersion strengthening and grain-refined microstructures.

关键词： Reciprocating extrusion mg-zn- Y alloy Icosahedral quasicrystal

Catalyst–Support Interaction in Polyaniline‑Supported Ni_(3)Fe Oxide to Boost Oxygen Evolution Activities for Rechargeable zn‑Air Batteries

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Nano-micro Letters 2025年第1期17卷 176-190页

作者： Xiaohong zou Qian Lu mingcong tang Jie Wu Kouer zhang Wenzhi Li Yunxia Hu Xiaomin Xu Xiao zhang zongping Shao Liang An Department of mechanical Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China Jiangsu Key Laboratory of Atmospheric Environment monitoring and Pollution Control Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and TechnologyNanjing University of Information Science and TechnologyNanjing 210044People’s Republic of China Department of Chemistry The Chinese University of Hong KongMa Lin BuildingShatinHong Kong SAR 999077People’s Republic of China WA School of mines:minerals Energy and Chemical Engineering(WASM‑MECE)Curtin UniversityPerthWA 6102Australia Research Institute for Advanced manufacturing The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China Research Institute for Smart Energy The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China

Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3)Fe oxide/PANI)with a robust hetero-interface,which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm^(-2)and specific activity of 2.08 mA cm_(ECSA)^(-2)at overpotential of 300 mV,3.84-fold that of Ni_(3)Fe *** is revealed that the catalyst–support interaction between Ni_(3)Fe oxide and PANI support enhances the Ni–O covalency via the interfacial Ni–N bond,thus promoting the charge and mass transfer on Ni_(3)Fe *** the excellent activity and stability,rechargeable zn-air batteries with optimum Ni_(3)Fe oxide/PANI are assembled,delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm^(-2).The regulation of the effect of catalyst–support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts.

关键词： Catalyst-support interaction Supported catalysts Heterointerface Oxygen evolution reaction zn-air batteries

Preparation of modified Composite Nanofiltration membrane Synergistically Using Carboxylic multi- walled Carbon Nanotube and β-cyclodextrin

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Journal of Wuhan University of Technology(materials Science) 2025年第1期40卷 232-239页

作者： LIU Peng mAO Junpeng FANG Yanfeng YU Yunwu CHEN Changxiu tang Ning WAN Ye GU Yaxin LIU Yunxue WANG Lihua School of materials Science and Engineering Shenyang Jianzhu UniversityShenyang 110168China

A new modified blend ultrafiltration(UF)membrane with good hydrophilicity,high porosity and excellent anti-fouling performance was developed by using carboxylic multi-walled carbon nanotube(CmWCNT)as casting solution ***,a composite nanofiltration(NF)membrane with large water flux and good retention rate was fabricated by using the PVDF/CmWCNT blend UF membrane as the substrate,and polyvinyl alcohol(PVA),β-cyclodextrin(β-CD)and polyethylenimine(PEI)as the coating *** results show that with the appropriate addition of CmWCNT in the casting solution,the surface roughness,porosity and recovery rate of the PVDF/CmWCNT blend UF membrane is obviously *** water flux of blend UF membrane is significantly improved when the CmWCNT content increases from 0 wt%to 0.2 wt%.The water flux of blend UF membrane with 0.2 wt%CmWCNT is 162.7 L/(m^(2)·h),which is 44.3%higher than that of the pure PVDF ***β-CD content is 0.8 wt%,the retention rate of Congo red by PVDF/CmWCNT/β-CD composite NF membrane reaches 98.7%,which is 28.3%higher than that of single PVA/PEI modified *** research will provide a new idea and simple method for developing novel high-performance composite NF membranes.

关键词： CmWCNT cyclodextrin nanofiltration membrane

RECIPROCATING EXTRUSION OF IN SITU mg_2Si REINFORCED mg-Al BASED COmPOSITE

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Acta metallurgica Sinica(English Letters) 2008年第3期21卷 169-177页

作者： z.m. zhang C.J. Xu X.F. Guo S.z. Jia School of materials Science ＆ Engineering Xi＇an University of Technology Xi＇an 710048 China

m92Si reinforced mg-Al based composite with high amount o/silicon was prepared by permanent mould casting, and then extruded by reciprocating extrusion （RE） after the composite was processed by homogenization heat treatment. The effect of RE processing on the morphology and size of m92Si and the mechanical properties of the com- posite were investigated, to develop new ways to refine the m928i phase and improve its shape. The result showed that RE was very useful in refining the m92Si phase. The more the RE processing passes, the better the refining effect would be. moreover, the uniform distribution of m928i phases would be more in the composite. After the composite was processed by RE for 12 passes, most m92Si phases were equiaxed, with granular diameter below 20 μm, and distributed uniformly in the matrix of the composite. The mechanical properties of the composite could be increased prominently by RE processing, and were much higher than that in the as-cast state. As the temperature rises, the tensile strength is reduced. For the composite RE processed for 12 passes, the tensile strength, yield strength, and elongation are 325.9 mPa, 211.4 mPa, and 3.3% at room temperature, whereas, 288.2 mPa, ,207.7 mPa, and 7.8%, respectively, at 150℃. In comparison with the properties at room temperature, the tensile strength and yield strength are high and only decrease by 11.6% and 1.8% at 150℃. The m928i reinforced mg-Al based composite possesses good heat resistance at 150℃. The excellent resistance to effect of heat is attributed to the high melting tempera- ture and good thermal stability of fine mg2Si phases, which are distributed uniformly in the composite, and effectively hinder the grain boundary gliding and dislocation movement.

关键词： Reciprocating extrusion magnesium alloy In situ composite Elevated temperature property