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Probing multi-mobility edges in quasiperiodic mosaic lattices

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Science Bulletin 2025年第1期70卷 58-63页

作者： Jun Gao Ivan M.Khaymovich Xiao-Wei Wang Ze-Sheng Xu Adrian Iovan Govind Krishna Jiayidaer Jieensi Andrea Cataldo Alexander V.Balatsky Val Zwiller ali W.Elshaari Department of Applied Physics KTH Royal Institute of TechnologyAlbanova University CentreStockholm SE-10691Sweden Nordita Stockholm University and KTH Royal Institute of TechnologyStockholm SE-10691Sweden Institute for Physics of Microstructures Russian Academy of SciencesNizhny Novgorod 603950Russia Center for Integrated Quantum Information Technologies(IQIT) School of Physics and Astronomy and State Key Laboratory of Advanced Optical Communication Systems and NetworksShanghai Jiao Tong UniversityShanghai 200240China Department of Physics University of ConnecticutStorrsConnecticut 06269USA

The mobility edge(ME)is a crucial concept in understanding localization physics,marking the critical transition between extended and localized states in the energy *** localization scaling theory predicts the absence of ME in lower dimensional ***,the search for exact MEs,particularly for single particles in lower dimensions,has recently garnered significant interest in both theoretical and experimental studies,resulting in notable ***,several open questions remain,including the possibility of a single system exhibiting multiple MEs and the continual existence of extended states,even within the strong disorder ***,we provide experimental evidence to address these questions by utilizing a quasiperiodic mosaic lattice with meticulously designed nanophotonic *** observations demonstrate the coexistence of both extended and localized states in lattices with broken duality symmetry and varying modulation *** single-site injection and scanning the disorder level,we could approximately probe the ME of the modulated *** results corroborate recent theoretical predictions,introduce a new avenue for investigating ME physics,and offer inspiration for further exploration of ME physics in the quantum regime using hybrid integrated photonic devices.

关键词： Mobility edge Localization physics Mosaic lattice Nanophotonics

NOx emissions of turbofan powered unmanned aerial vehicle for complete flight cycle

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Chinese Journal of Aeronautics 2020年第6期33卷 1683-1691页

作者： ali DINC College of Engineering and Technology American University of the Middle EastKuwait

Unmanned Aerial Vehicles(UAVs) have been getting more and more popular in both civil and military arena. Similar to manned aircraft, their propulsion systems or engines emit harmful gases such as nitrogen oxides. Since UAVs have different mission profiles and operational parameters than manned aircraft, it is worthy to investigate their NOx emissions. Therefore, in this study, NOx emissions of a turbofan powered UAV for complete flight cycle was calculated and optimized within a range of altitude and speed parameters. NOx emissions were calculated based on ICAO ground test data and corrected to any speed and altitude during flight legs using both Boeing Fuel Flow Method 2 and DLR Fuel Flow Method. Total NOx emissions were calculated for complete flight cycles for different altitude and speed parameters. Numerical results were presented graphically and additionally optimization studies were conducted. Optimization studies include determination and comparison of speed and altitude for minimum NOx emissions by the two fuel flow methods and maximum loiter time achievable by UAV.

关键词： Aircraft performance Cycle analysis NOv emissions Optimization Turbofan cnlgine UAV

Genuine entanglement under squeezed generalized amplitude damping channels with memory

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Chinese Physics B 2024年第2期33卷 158-163页

作者： Mazhar ali Department of Electrical Engineering Faculty of EngineeringIslamic University MadinahMadinah 107Saudi Arabia

We study genuine entanglement among three qubits undergoing a noisy process that includes dissipation, squeezing,and decoherence. We obtain a general solution and analyze the asymptotic quantum states. We find that most of these asymptotic states can be genuinely entangled depending upon the parameters of the channel, memory parameter, and the parameters of the initial states. We study Greenberger–Horne–Zeilinger(GHZ) states and W states, mixed with white noise,and determine the conditions for them to be genuinely entangled at infinity. We find that for these mixtures, it is possible to start with a bi-separable state(with a specific mixture of white noise) and end with genuine entangled states. However, the memory parameter μ must be very high. We find that in contrast to the two-qubit case, none of the three-qubit asymptotic states for n → ∞ are genuinely entangled.

关键词： genuine entanglement squeezed thermal baths multipartite states

Flow Confinement Effects on the Wake Structure behind a Pitching Airfoil： A Numerical Study Using an Immersed Boundary Method

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Journal of Bionic Engineering 2017年第1期14卷 88-98页

作者： ali Akbar Hosseinjani ali Ashrafizadeh Faculty of Mechanical Engineering K. N. Toosi University of Technology Tehran P.O.B. 19395-1999 Iran

The flow patterns and wake structures behind a pitching airfoil in an un-bounded domain have been studied extensively. In contrast, the flow phenomena associated with a pitching airfoil near a solid boundary have not been adequately studied or reported. This paper aims at filling this research gap by considering the flow confinement effects on the flow pattern around a pitching airfoil. To achieve this goal, the flow fields around a flapping airfoil in un-bounded, bounded and semi-bounded domains are studied and compared. Numerical simulations are carried out at a fixed Reynolds number, Re = 255, and at a fixed oscillation frequency corresponding to St = 0.22. An accurate immersed boundary method is employed to calculate the unsteady flow fields around the airfoil at various flapping amplitudes. It is argued that two flow mechanisms, here called ＂the interaction effect＂ and ＂the induced reverse flow effect＂ are responsible for the variations of the flow field due to the presence of a nearby solid boundary.

关键词： immersed boundary method pitching airfoil vortex street induced momentum aligned vortex

An extended iterative direct-forcing immersed boundary method in thermo-fluid problems with Dirichlet or Neumann boundary conditions

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Journal of Central South University 2017年第1期24卷 137-154页

作者： ali Akbar Hosseinjani ali Ashrafizadeh Faculty of Mechanical Engineering K.N.Toosi University of TechnologyP.O.B.19395-1999 TehranIran

An iterative direct-forcing immersed boundary method is extended and used to solve convection heat transfer *** pressure,momentum source,and heat source at immersed boundary points are calculated simultaneously to achieve the best *** of convection heat transfer problems with both Dirichlet and Neumann boundary conditions are *** approaches for the implementation of Neumann boundary condition,*** and indirect methods,are introduced and compared in terms of accuracy and computational *** test cases include forced convection on a heated cylinder in an unbounded flow field and mixed convection around a circular body in a lid-driven ***,the proposed method is applied to study the mixed convection around a heated rotating cylinder in a square enclosure with both iso-heat flux and iso-thermal boundary *** results show that the order of accuracy of the indirect method is less than the direct ***,the indirect method takes less computational time both in terms of the implementation of the boundary condition and the post processing time required to compute the heat transfer variables such as the Nusselt *** is concluded that the iterative direct-forcing immersed boundary method is a powerful technique for the solution of convection heat transfer problems with stationary/moving boundaries and various boundary conditions.

关键词： immersed boundary method direct forcing thermo-fluid problems neumann boundary condition

Effects of different friction stir welding conditions on the microstructure and mechanical properties of copper plates

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International Journal of Minerals,Metallurgy and Materials 2016年第7期23卷 799-809页

作者： ali Alavi Nia ali Shirazi Department of Mechanical Engineering Bu-Ali Sina University

Friction stir welding is a new and innovative welding method used to fuse materials. In this welding method, the heat generated by friction and plastic flow causes significant changes in the microstructure of the material, which leads to local changes in the mechanical properties of the weld. In this study, the effects of various welding parameters such as the rotational and traverse speeds of the tool on the microstructural and mechanical properties of copper plates were investigated; additionally, Charpy tests were performed on copper plates for the first time. Also, the effect of the number of welding passes on the aforementioned properties has not been investigated in previous studies. The results indicated that better welds with superior properties are produced when less heat is transferred to the workpiece during the welding process. It was also found that although the properties of the stir zone improved with an increasing number of weld passes, the properties of its weakest zone, the heat-affected zone, deteriorated.

关键词： copper friction stir welding mechanical properties microstructure

Sero-Prevalence of Peste des Petits Ruminants Virus Antibodies in Sudanese Sheep and Goats before and after Vaccination

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Journal of Biosciences and Medicines 2025年第1期13卷 21-40页

作者： Omer Algezoli Selma Kamal Yazeed Raouf Alamin Mozdalifa Hiba ali Mohamed Aljameel Salih Sir Elkhatim Sulieman Ahmed Ibtesam Fadul Elsied Tageldin Nour Mohamed Abdalla Viral Vaccine Production Department Central Veterinary Research Laboratory Khartoum Sudan College of Veterinary Medicine Sudan University of Science and Technology Khartoum-North Sudan Epidemiology Department Central Veterinary Research Laboratory Khartoum Sudan Foot and Mouth Disease Department Central Veterinary Research Laboratory Khartoum Sudan Virology Department Central Veterinary Research Laboratory Khartoum Sudan Nyala Veterinary Research Laboratory Nyala Sudan Damazine Veterinary Research Laboratory Damazine Sudan Al Obeid Veterinary Research Laboratory Al Obeid Sudan

Peste des petits ruminants virus (PPRV) antibodies were studied in Sudanese sheep and goats (n = 855) before and after vaccination with a locally produced Nigeria 75/1 vaccine using a commercial competitive ELISA (cELISA) kit. Animals were kept healthy under field conditions, in four states: Blue Nile (n = 250), North Kordofan (n = 189), South Darfur (n = 225) and the Northern State (n = 191). Before vaccination, the overall sero-prevalence of PPRV antibodies was 54.6% (53.2% - 56%, 95% CI);high (64.8% - 76.4%, 95% CI) in Blue Nile State, medium (50.5% - 61.9%, 95% CI) in North Kordofan State and South Darfur State and low (28.6% - 35.2% 95%, CI) in Northern State. In high-risk areas (high sero-prevalence), Blue Nile (70.4%) and North Kordofan (57.7%), middle age groups (7 - 12 and 13 - 18 months) were identified as high-risk age. Middle age groups showed lower sero-prevalence than preceding (3 - 6 months) and subsequent (>18 months) age groups while the risk of exposure increased with age. Current and previous findings suggested a transmission pathway of PPRV involving the South Eastern border (Blue Nile) and neighbouring Central Sudan to North Kordofan. One month after vaccination 88.4% (343/388) of sero-negative animals were sero-converted suggesting the efficacy of the locally produced Nigeria 75/1 vaccine. Even if only individuals in the high-risk age group (7 - 18 months) were vaccinated, the overall population immunity (OPI) in high-risk areas (the Blue Nile and North Kordofan) would have surpassed the threshold of 70%, which is indicated for blocking PPRV transmission. However, lower vaccination coverage is expected in wider vaccination programmes. These findings primarily justified the targeting of PPR control in Sudan through the vaccination of high-risk age groups in high-risk areas.

关键词： Peste des Petits Ruminants (PPR) Vaccination Efficacy Seroprevalence Herd Immunity High-Risk Area

Effects of Fe_2O_3 Nanoparticles on Water Permeability and Strength Assessments of High Strength Self-Compacting Concrete

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Journal of Materials Science & Technology 2012年第1期28卷 73-82页

作者： ali Khoshakhlagh ali Nazari Gholamreza Khalaj Department of Materials Engineering Science and Research BranchIslamic Azad University Department of Materials Engineering Saveh BranchIslamic Azad University

In this work, compressive, flexural and split tensile strength together with coefficient of water absorption of high performance self-compacting concrete containing different amount of Fe2Os nanoparticles have been investigated. The strength and the water permeability of the specimens have been improved by adding Fe2Os nanoparticles in the cement paste up to 4.0 wt%. Fe203 nanoparticle as a foreign nucleation site could accelerate C-S-H gel formation as a result of increased crystalline Ca（OH）2 amount especially at the early age of hydration and hence increase the strength of the specimens. In addition, Fe203 nanoparticles are able to act as nanofillers and recover the pore structure of the specimens by decreasing harmful pores to improve the water permeability. Several empirical relations have been presented to predict the flexural and the split tensile strength of the specimens by means of the corresponding compressive strength at a certain age of curing. Accelerated peak appearance in conduction calorimetry tests, more weight loss in thermogravimetric analysis and more rapid appearance of peaks related to hydrated products in X-ray diffraction results indicate that Fe203 nanoparticles up to 4 wt% could improve the mechanical and the physical properties of the specimens.

关键词： Water permeability Fe203 nanoparticles Compressive strength Split tensilestrength Flexural strength

A VERSATILE AND REGIOSELECTIVE SYNTHESIS OF VICINAL AZIDOALCOHOLS USING CROSS-LINKED POLY(4-VINYLPYRIDINE) SUPPORTED AZIDE ION UNDER SOLVENT-FREE CONDITIONS

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Chinese Journal of Polymer Science 2013年第12期31卷 1660-1669页

作者： Mohammad ali Karimi Zarchi ali Tarabsaz Department of Chemistry College of ScienceYazd University

A new polymeric reagent, cross-linked poly（4-vinylpyridine） supported azide ion, [P4-VP]N3, was introduced as polymeric reagents for efficient and regioselective conversion of epoxides to azidohydrins in the presence of cross-linked poly（4-vinylpyridine） supported sulfuric acid, [P4-VP]H2SO4, as a solid proton source and as catalyst under solvent-free conditions. The advantages of this polymeric reagent over some of those reported in the literature are easy work-up procedure and regeneration of the reagent.

关键词： Ring opening of epoxide fl-Azidoalcohols Poly(4-vinytpyridine) Solvent-free conditions Regioselectivity.