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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKHARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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A modification of Extended Homoclinic Test Approach to Solve the(3+1)-Dimensional Potential-YTSF Equation

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Chinese Physics Letters 2011年第4期28卷 4-7页

作者： m.T.Darvishi mohammad Najafi Department of mathematics Razi UniversityKermanshah 67149Iran

By means of the extended homoclinic test approach(EHTA)one can solve some nonlinear partial differential equations(NLPDEs)in their bilinear *** an NLPDE has no bilinear closed form we can not use this *** modify the idea of EHTA to obtain some analytic solutions for the(3+1)-dimensional potential-Yu-Toda-Sasa-Fukuyama(YTSF)equation by obtaining a bilinear closed form for *** comparison of this method and other analytic methods,like HAm,HTA and three-wave methods,we can see that the new idea is very easy and straightforward.

关键词： method bilinear analytic

Prediction of Turbulent Flow Structure in a Fully Developed Rib-Roughened Narrow Rectangular Channel

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Journal of Thermal Science 2009年第2期18卷 126-136页

作者： md.Shafiqul islam m.Kaminaga R.Hino m.monde Atomic Energy Research Establishment Japan Atomic Energy Agency (JAEA) Department of mechanical Engineering Saga University

Fully developed turbulent water-flow structure over one-side repeated-ribs in narrow two-dimensional rectangular channels was investigated experimentally by Particle Image Velocimetry （PIV） and analytically by the standard k-ε and nonlinear k-ε turbulent models. Two rib-pitch to height ratios （p/k） of 10 and 20 were investigated while the rib height was held constant at 4 mm. The rib height-to-channel equivalent diameter ratio （k/De） was 0.1. The streamwise mean velocity and turbulent kinetic energy distributions at six selected axial stations from the center rib for the two Reynolds number （Re） of 7,000 and 20,000 were obtained and compared with the predicted one. The performance ability in predicting separating and reattaching turbulent water-flow between the standard K-ε and nonlinear k-ε models had yielded no clear conclusion. A large-scale turbulent eddy was generated by the rib promoter and then propagated into the mainstream flow, which led to the deformation of the velocity profile. The turbulent kinetic energy was increased about two times higher at p/k = 20 than that at p/k =10 under the two Reynolds numbers. The effect of the p/k value and the Reynolds number （Re） on reattachment length （XR） was investigated and showed that the p/k and Re had no significant effect on the reattachment length beyond a critical value of Re = 15,000 where XR was found to be approximately 4 times of the rib height under water-flow condition.

关键词： Turbulent water-flow structure repeated-ribs narrow rectangular channels two-dimensional analysis reattachment length

Effects of loading rate and hydraulic residence time on anoxic sulfide biooxidation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第7期8卷 1149-1156页

作者： mAHmOOD Qaisar islam Ejazul Department of Environmental Engineering Zhejiang University

The optimal operation conditions in an anoxic sulfide oxidizing (ASO) bioreactor were investigated. The maximal removal rates for sulfide and nitrate were found to be 4.18 kg/(m3·d) and 1.73 kg/(m3·d), respectively. The volumetrical volumetric loading rates (LRs) observed through decreasing hydraulic retention time (HRT) at fixed substrate concentration are higher than those by increasing substrate concentration at fixed HRT. The sulfide oxidation in ASO reactor was partially producing both sulfate and sulfur; but the amount of sulfate produced was approximately one third that of sulfur. The process was able to tolerate high sulfide concentration, as the sulfide removal percentage always remained near 99% when influent concentration was up to 580 mg/L. It tolerated relatively lower nitrate concentration because the removal percentage dropped to 85% when influent con- centration was increased above 110 mg/L. The process can tolerate shorter HRT but careful operation is needed. Nitrate conversion was more sensitive to HRT than sulfide conversion since the process performance deteriorated abruptly when HRT was decreased from 3.12 h to 2.88 h. In order to avoid nitrite accumulation in the reactor, the influent sulfide and nitrate concentrations should be kept at 280 mg/L and 67.5 mg/L respectively. Present biotechnology is useful for removing sulfides from sewers and crude oil.

关键词： Anaerobic processes Anoxic nitrate removal Biodesulfurization Biotransformation Fluidized bed bioreactors Hydraulic residence time (HRT)

Facile synthesis of ironenickelecobalt ternary oxide(FNCO)mesoporous nanowires as electrode material for supercapacitor application

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Journal of materiomics 2022年第1期8卷 221-228页

作者： muhammad Usman muhammad Tayyab Ahsan Sofia Javed Zeeshan Ali Yiqiang Zhan Irfan Ahmed Sajid Butt mohammad islam Asif mahmood m.Aftab Akram School of Chemical and materials Engineering National University of Sciences and Technology(NUST)Sector H-12Islamabad44000Pakistan Department of materials Science and Engineering College of EngineeringPeking University100871BeijingChina State Key Laboratory of ASIC and System Center of Micro-Nano SystemSISTFudan UniversityShanghai200433China Department of materials Science and Engineering Institute of Space TechnologyIslamabad44000Pakistan New mexcico Institute of mining&Technology SocorroNM 87801USA School of Chemical and Biomolecular Engineering The University of Sydney2006SydneyAustralia

Transition metal Oxides have drawn significant attention due to their reversible chemical redox reaction and long-life *** agglomeration and shrinkage/expansion of transition metal oxides in the nanosize regime have a noticeable effect on their electrochemical *** in this work,mesoporous nanowires(NWs)with a typical composition of iron-nickel-cobalt ternary oxide(FNCO)are synthesized using a simple,facile and cost-effective hydrothermal process followed by furnace *** NWs are then extensively investigated as an electrode material for supercapacitor *** compare the electrochemical properties,nanowires of nickel-cobalt oxide(NCO),iron-cobalt oxide(FCO)and cobalt oxide(CO)were also produced by following the same *** FNCO NWs are found to overcome the shortcomings in the electrochemical energy storage devices by exhibiting higher values of specific capacitance(2197 Fg^(-1))and energy density(109 Whkg^(-1))at 1 Ag^(-1) current ***,the FNCO NWs also showed a cyclic charge/discharge stability of 96%even up to 20,000 ***,a FNCO//graphene asymmetric device,fabricated with FNCO NWs and graphene as positive and negative electrodes,respectively,which exhibit high energy density(47 Whkg^(-1)),power density(375 Wkg^(-1))and excellent capacitance retention(86%)after 15,000 cycles.

关键词： Electrochemistry Hydrothermal synthesis Nanowires Supercapacitor Transition metal oxides

Artificial Neural Network modeling for Predicting Thermal Conductivity of EG/Water-Based CNC Nanofluid for Engine Cooling Using Different Activation Functions

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Frontiers in Heat and mass Transfer 2024年第2期22卷 537-556页

作者： mdmunirul Hasan mdmustafizur Rahman mohammad Saiful islam Wong Hung Chan Yasser m.Alginahi muhammad Nomani Kabir Suraya Abu Bakar Devarajan Ramasamy Faculty of Computing Universiti Malaysia Pahang Al-Sultan AbdullahPekanPahang26600Malaysia Faculty of mechanical and Automotive Engineering Technology Universiti Malaysia Pahang Al-Sultan AbdullahPekanPahang26600Malaysia Department of management and Information Technology St.Francis College179 Livingston StBrooklynNY11201USA Dell Technologies Data Analyticsand AutomationBukit TengahBukit Mertajam14000Malaysia Department of Computer Science Adrian CollegeAdrianMIUSA Department of Computer Science&Engineering United International University BangladeshUnited CityMadani AvenueBaddaDhaka1212Bangladesh

A vehicle engine cooling system is of utmost importance to ensure that the engine operates in a safe temperature *** most radiators that are used to cool an engine,water serves as a cooling *** performance of a radiator in terms of heat transmission is significantly influenced by the incorporation of nanoparticles into the cooling *** and uniformity of nanoparticle distribution are the two major factors for the practical use of *** shape and size of nanoparticles also have a great impact on the performance of heat *** researchers are investigating the impact of nanoparticles on heat *** study aims to develop an artificial neural network(ANN)model for predicting the thermal conductivity of an ethylene glycol(EG)/waterbased crystalline nanocellulose(CNC)nanofluid for cooling internal combustion *** implementation of an artificial neural network considering different activation functions in the hidden layer is made to find the bestmodel for the cooling of an engine using the *** of the model with different activation functions in artificial neural networks are analyzed for different nanofluid concentrations and *** artificial neural networks,Levenberg–marquardt is an optimization approach used with activation functions,including Tansig and Logsig functions in the training *** findings of each training,testing,and validation phase are presented to demonstrate the network that provides the highest level of *** best result was obtained with Tansig,which has a correlation of 0.99903 and an error of 3.7959×10^(–8).It has also been noticed that the Logsig function can also be a good model due to its correlation of 0.99890 and an error of 4.9218×10^(–8).Thus ourANNwith Tansig and Logsig functions demonstrates a high correlation between the actual output and the predicted output.

关键词： Artificial neural network activation function thermal conductivity nanocellulose

mULTIPLE POINTS OF ImmERSIONS OF m^6■R^7

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Acta mathematica Scientia 2011年第1期31卷 259-267页

作者： mohammad A.Asadi-Golmankhaneh Department of mathematics University of Urmia

In this article, we determine the multiple point set of immersions of 6-dimensional manifolds into 7-dimensional Euclidean space R7. The method is to evaluate the characteristic numbers of these manifolds. By a certain method, these numbers can be read of from the Hurewicz image ofh ： π7QmO（1） → H7QmO（1）.In particular, we show that for any immersion of P 6 in R7 the double, 4-fold and 6-fold point manifolds are cobordant to boundaries and triple point manifolds cobordant to P 4, 5-fold point manifolds cobordant to P 2 and 7-fold point manifold are odd number.

关键词： Immersion Hurewicz homomorphism spherical classes Stiefel-Whitney number

Deposition behavior and tribological properties of diamond-like carbon coatings on stainless steels via chemical vapor deposition

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International Journal of minerals,metallurgy and materials 2018年第11期25卷 1335-1343页

作者： Labani mustafi m.m.Rahman mohammad Nur E Alam Al Nasim mohammad Asaduzzaman Chowdhury m.H.monir School of materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Engineering RMIT UniversityMelbourneVictoria 3001Australia Dhaka University of Engineering and Technology Gazipur 1707Bangladesh

A systematic investigation was carried out to observe the deposition rate of a diamond-like carbon(DLC) coating on two stainless steel substrates by chemical vapor deposition(CVD). The objective of this research is to study the deposition behavior of the DLC coating and its tribological properties in different combinations of methane(CH_4) and nitrogen, which were used as precursor gases. The results reveal that the deposition rate increases with increasing CH_4 content up to 50 vol%. The hardness of the DLC-deposited layer also increases while the friction coefficient decreases with increasing CH_4 gas content up to 50% in the precursor gas mixture.

关键词： diamond-like carbon chemical vapor deposition methane and nitrogen gas mixtures deposition rate hardness friction coefficient

In Silico Screening of Natural Products as Potential Inhibitors of SARS-CoV-2 Using molecular Docking Simulation

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Chinese Journal of Integrative medicine 2022年第3期28卷 249-256页

作者： Rajib Hossain Chandan Sarkar Shardar mohammad Hafiz Hassan Rasel Ahmed Khan mohammad Arman Pranta Ray muhammad Torequl islam Sevgi Durna Dastan Javad Sharifi-Rad Zainab m. Almarhoon miquel martorell William N. Setzer Daniela Calina Department of Pharmacy Life Science FacultyBangabandhu Sheikh Mujibur Rahman Science and Technology UniversityGopalganj(8100)Bangladesh Harmacy Discipline Life Science SchoolKhulna UniversityKhulna-9280Bangladesh Departme nt of Pharmacy In ternational Islamic UniversityChittagongBangladesh Department of Biomedical Engin eeri ng Huazho ng Un iversity of Science and Tech no logyWuhan(430074)China Department of Biology Faculty of ScienceSivas Cumhuriyet UniversitySivas(58140)Turkey Beekeeping Development Application and Research Center Sivas Cumhuriyet UniversitySivas(58140)Turkey School of medicine University of AzuayCuencaEcuador Department of Chemistry College of ScienceKing Saud UniversityRiyadh(11451)Saudi Arabia Department of Nutrition and Dietetics Faculty of Pharmacyand Centre for Healthy LivingUniversity of ConcepcionConcepcion(4070386)Chile Department of Chemistry University of Alabama in HuntsvilleHuntsvilleAL(35899)USA Aromatic Plant Research Center 230 N 1200 ESuite 100LehiUT(84043)USA Department of Clinical Pharmacy University of Medicine and Pharmacy of CraiovaCraiova(200349)Romania

Objective:To explore potential natural products against severe acute respiratory syndrome coronavirus(SARS-CoV-2)via the study of structural and non-structural proteins of human ***:In this study,we performed an in-silico survey of 25 potential natural compounds acting against *** docking studies were carried out using compounds against 3-chymotrypsin-like protease(3 CL^(PHO)),papain-like protease(PL^(PRO)),RNA-dependent RNA polymerase(RdRp),non-structural protein(nsp),human angiotensin converting enzyme 2 receptor(hACE2 R),sapike glycoprotein(S protein),abelson murine leukemia viral oncogene homolog 1(ABL1),calcineurin-nuclear factor of activated T-cells(NFAT)and transmembrane protease serine ***:Among the screened compounds,amentoflavone showed the best binding affinity with the 3 CL^(PRO),RdRp,nsp13,nsp15,hACE2 R,ABL1 and calcineurin-NFAT;berbamine with hACE2 R and ABL1;cepharanthine with nsp10,nsp14,nsp16,S protein and ABL1;glucogallin with nsp15;and papyriflavonol A with PL^(PRO)*** good interacting compounds were juglanin,betulinic acid,betulonic acid,broussooflavan A,tomentin A,B and E,7-methoxycryptopleurine,aloe emodin,quercetin,tanshinone I,tylophorine and furruginol,which also showed excellent binding affinity towards a number of target *** of these compounds showed better binding affinities towards the target proteins than the standard drugs used in this ***:Natural products or their derivatives may be one of the potential targets to fight against SARS-CoV-2.

关键词： SARS-CoV-2 natural products-derived anti-SARS-CoV-2 candidates structural proteins nonstructural proteins molecular docking

Cardiac myxomas:A narrative review

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World Journal of Cardiology 2022年第4期14卷 206-219页

作者： A K m monwarul islam Department of Cardiology National Institute of Cardiovascular DiseasesDhaka 1207Bangladesh

Cardiac myxomas are common primary neoplasms of the *** are biologically benign but“functionally malignant”because of the potential for *** arise most commonly from the left atrium,but no chambers of the heart are *** may be sporadic in the majority but also familial as a part of the Carney *** morphological forms exist:polypoid and *** myxomas often present with obstructive features,while the papillary forms are more prone to *** is still controversial;the current view centres around origin from the primitive pluripotent mesenchymal *** may be of giant proportion,be calcified or get *** presentation typically involves the triad of intracardiac obstruction,embolic events and constitutional *** examination findings may simulate those of mitral or tricuspid *** presence of tumour plop and change of the physical findings with changing position may help differentiation between the *** is the investigation of *** polypoid or papillary mobile mass within the atrial cavity remaining attached to the interatrial septum through a stalk are the tell-tale echocardiographic *** magnetic resonance and computed tomographic scanning may have incremental diagnostic *** examination reveals abundant loose myxoid stroma with scattered round,polygonal or stellate cells with dense irregular *** testing may detect mutations in the PRKAR1A gene in the familial form of cardiac myxoma,*** Carney *** excision is the mainstay of treatment with low operative mortality,excellent postoperative survival and low recurrence *** current trend favours minimal-access surgery with or without robotic *** should have appropriate preparedness to make a timely diagnosis and enthusiastic treatment to avoid potentially fatal complications.

关键词： myxoma Cardiac Neoplasm Carney Complex Echocardiography Embolism