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Effect of spark plasma sintering and reinforcements on the formation of ultra-fine and nanograins in AA2024-Tib2-Y hybrid composites

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Progress in Natural Science:materials International 2022年第1期32卷 79-86页

作者： ch.Suresh Vidyasagar D.b.Karunakar Department of Architecture and Planning Indian Institute of Technology Roorkee mechanical and Industrial Engineering Department Indian Institute of Technology Roorkee

This study reports the influence of sintering mechanism and reinforcement materials on the formation of ultra-fine and nanograins in Al-Tib-Y nanohybrid composites. The mechanical properties of the composites and their corresponding micro and nanostructures are correlated. The experimental and characterization results revealed that despite the addition of Tib, the hard and brittle AlTi phase formation in the composites was suppressed and hence, their ductility was retained. It was found that yttrium content of 0.3 wt% was the optimum amount which created advantageous spark plasma sintering conditions, and the addition of 0.3 wt% promoted the formation of bi-modal size grains（ultra-fine and nano） along with micro grains, Ω and other nano precipitates, resulting in a significant enhancement in the composite properties. The formation of ultra-fine and nanograins may be attributed to the combined effect of melting and rapid solidification at necking zones due to Joule’s heating and thermomechanical fatigue. Among all the sintered composites, the highest hardness（137 HV）, ultimate tensile strength（UTS）(496 mPa), yield strength（YS）(438 mPa) with 15.7% elongation were obtained in the sintered sample reinforced with 1.0 wt% Tiband 0.3 wt% yttrium.

关键词： Hybrid composites Ultra-fine grains Nano grains Spark plasma sintering Nano precipitates microstructure

Copy-move Forgery Verification in Images Using Local Feature Extractors and Optimized Classifiers

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big Data mining and Analytics 2023年第3期6卷 347-360页

作者： S.b.G.Tilak babu ch Srinivasa Rao University College of Engineering JNTU KakinadaKakinada 533003India. Department of ECE JNTUK UCEVizianagaram 535003India.

Passive image forgery detection methods that identify forgeries without prior knowledge have become a key research *** copy-move forgery,the assailant intends to hide a portion of an image by pasting other portions of the same *** detection of such manipulations in images has great demand in legal evidence,forensic investigation,and many other *** paper aims to present copy-move forgery detection algorithms with the help of advanced feature descriptors,such as local ternary pattern,local phase quantization,local Gabor binary pattern histogram sequence,Weber local descriptor,and local monotonic pattern,and classifiers such as optimized support vector machine and optimized *** proposed algorithms can classify an image efficiently as either copy-move forged or authenticated,even if the test image is subjected to attacks such as JPEG compression,scaling,rotation,and brightness ***,CASIA,and mICC datasets and a combination of ComoFoD and CASIA datasets images are used to quantify the performance of the proposed *** proposed algorithms are more efficient than state-of-the-art algorithms even though the suspected image is post-processed.

关键词： copy move forgery detection image authentication passive image forgery detection blind forgery detection

Spectroscopic and fluorescence properties of Sm^(3+)-doped zincfluorophosphate glasses

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Journal of Rare Earths 2014年第10期32卷 918-926页

作者： V.b.Sreedhar ch.basavapoornima C.K.Jayasankar Department of Physics Sri Venkateswara University Department of Physics National Degree and P.G. College

Optical absorption and fluorescence spectra of Sm3＋-doped zincfluorophosphate glasses with molar composition of 44P2O5＋17K20＋9Al2O3＋（30-χ）ZnF2＋χSm2O3 （χ=0.01 mol.%, 0.05 mol.%, 0.1 mol.%, 0.5 mol.%, 1.0 mol.%, 2.0 and 3.0 mol.%） referred as PKAZFSm were prepared by melt quenching technique and were characterized through Raman, absorption, emission and decay curve analysis. From the absorption spectra, Judd-Ofelt intensity parameters were determined and were used to predict radiative properties such as transition probabilities （AR, radiative lifetimes （τR）, branching ratios （βR）, effective bandwidths （△λeff） and stimulated emission cross-section （σ（λp）） for the excited 4G5/2 luminescent level. The decay curve for the 4G5/2 level was single exponential for lower concentration and became non-exponential for higher concentrations. The non-exponential nature of the decay curves of the 4G5/2 level increased with increase in Sm3＋ ions concentration accompanied by decrease in lifetime due to energy transfer processes among the Sm3＋ ions. The non-exponential decay curves was well fitted to the generalized Inokuti-Hirayama model for S=6, indicating that the energy transfer among optically active ions was of dipole-dipole interaction. The cross-relaxation mechanism responsible for the quenching of lifetimes and the effect of variation of concentration on the spectroscopic properties were also discussed.

关键词： zincfluorophosphate glasses samarium Raman spectrum optical properties fluorescence properties rare earths

Association of the glycemic background patterns and the diabetes management efficacy in poorly controlled type 2 diabetes

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World Journal of Diabetes 2025年第1期16卷 74-90页

作者： Ayşe N Erbakan müzeyyen Arslan bahadır FatoşN Kaya büşra Güleç miraçVural Keskinler Ümmügülsüm AktemurÇelik Özge Faydalıel banu mesçi Aytekin Oğuz Department of Internal medicine Prof Dr Suleyman Yalcin City HospitalIstanbul Medeniyet UniversityIstanbul 34722Türkiye Department of Family medicine Istanbul Medeniyet UniversityIstanbul 34722Türkiye

bACKGROUND Inadequate glycemic control in patients with type 2 diabetes(T2Dm)is a major public health problem and a significant risk factor for the progression of diabetic *** To evaluate the effects of intensive and supportive glycemic management strategies over a 12-month period in individuals with T2Dm with glycated hemoglobin(HbA1c)≥10%and varying backgrounds of glycemic *** This prospective observational study investigated glycemic control in patients with poorly controlled T2Dm over 12 *** were categorized into four groups based on prior glycemic history:Newly diagnosed,previously well controlled with recent worsening,previously off-target but now worsening,and HbA1c consistently above 10%.HbA1c levels were monitored quarterly,and patients received medical,educational,and dietary support as *** analysis focused on the success rates of good glycemic control and the associated factors within each *** The study showed significant improvements in HbA1c levels in all *** most significant improvement was observed in individuals newly diagnosed with diabetes:65%achieved an HbA1c target of≤7%.The results varied between participants with different glycemic control histories,followed by decreasing success rates:39%in participants with previously good glycemic control,21%in participants whose glycemic control had deteriorated compared to before,and only 10%in participants with persistently poor control,with mean HbA1c levels of 6.3%,7.7%,8.2%,and 9.7%,*** one year,65.2%of the“newly diagnosed patients”,39.3%in the“previously controlled group”,21.9%in the“previously off-target but now worsened'”group and 10%in the“poorly controlled from the start”group had achieved HbA1c levels of 7 and *** In poorly controlled diabetes,the rate at which treatment goals are achieved is associated with the glycemic background characteristics,emphasizing the need for tailored ***

关键词： Type 2 diabetes mellitus Glycated hemoglobin Glycemic control Patient-centered care Diabetes management glycemic background

On a biseparability criterion of bipartite qudit state

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chinese Physics b 2019年第8期28卷 42-49页

作者： b benzimoun m Daoud LPHE-modeling and Simulation Faculty of SciencesUniversity Mohammed ⅤRabatMorocco Department of Physics Faculty of Sciences-Ain ChockUniversity Hassan ⅡCasablancaMorocco Abdus Salam International Centre for Theoretical Physics TriesteItaly

In this paper,we propose a new approach to tackle the separability problem for bipartite qudit *** is based on the majorana representation which allows to represent a N-spinors(qudit)as a symmetric state of N spin-1/*** also discuss how we can exploit such representation and the notion of the biseparability of multipartite qubit states in the sense to establish new criteria of the separability problem based on the PPT and concurrence.

关键词： separability bipartite qubit state partial separability majorana representation

Cloud-based data security transactions employing blowfish and spotted hyena optimisation algorithm

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Journal of Control and Decision 2023年第4期10卷 494-503页

作者： ch.chakradhara Rao Tryambak Hiwarkar b.Santhosh Kumar CSE Department Sri Satya Sai University of Technology and Medical SciencesSehoreIndia CSE Department Guru Nanak Institute of TechnologyTelanganaIndia

because of its on-demand servicing and scalability features in cloud computing,security and confidentiality have converted to key *** transaction information on thirdparty servers carries significant dangers so that malicious individuals trying for illegal access to information data security *** research proposes a security-aware information transfer in the cloud-based on the blowfish algorithm(bFA)to address the *** user is verified initially with the identification and separate the imported data using pattern matching ***,bFA is utilised to encrypt and save the data in *** can safeguard the data and streamline the proof so that client cannot retrieve the information without identification which makes the environment *** suggested approach’s performance is evaluated using several metrics,including encryption time,decryption time,memory utilisation,and *** to the existing methodology,the investigational findings clearly show that the method takes the least time to data encryption.

关键词： blowfish algorithm cloud environment data encryption spotted hyena optimisation algorithm user authentication

Rotational and Vibrational Temperatures of Atmospheric Double Arc Argon-Nitrogen Plasma

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chinese Physics Letters 2007年第5期24卷 1317-1320页

作者：严建华屠昕马增益岑可法 b. G. chéon State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 UmR 6614 CNRS CORIA Saint Etienne du Rouvray 76801 France

The spectroscopic technique is employed to study the emission of atmospheric argon-nitrogen plasma jet generated by an original dc double anode plasma torch. The molecular bands of the N^＋2 first negative system are observed at the torch exit and chosen to evaluate the rotational and vibrational temperatures in comparison with the simulated spectra. The excitation temperature （Texc ≈ 9600 K） is determined from the boltzmann plot method. The results show that the rotational, vibrational, electron and kinetic temperatures are in good agreement with one another, which indicates that the core region of atmospheric double arc argon-nitrogen plasma jet at the torch exit is close to the local thermodynamic equilibrium state under our experimental conditions.

关键词： N-2(+) bAND

Phase diagrams and magnetic properties of the mixed spin-1 and spin-3/2 Ising ferromagnetic thin film: monte Carlo treatment

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chinese Physics b 2019年第2期28卷 414-419页

作者： b boughazi m boughrara m Kerouad Laboratoire Physique des matériaux et modélisation des Systémes(LP2mS) UnitéAssociée au CNRST-URAC:08Faculty of SciencesUniversity Moulay Ismail

Phase diagrams and magnetic properties of the mixed spin-1 and spin-3/2 Ising film with different single-ion anisotropies are investigated, by the use of monte Carlo simulation based on heat bath algorithms. The effects of the crystal-fields and the surface coupling on the phase diagrams are investigated in detail and the obtained phase diagrams are presented. Depending on the Hamiltonian parameters, the system exhibits both second-and first-order phase transitions besides tricritical point, triple point, and isolated critical end point.

关键词： monte Carlo simulation thin film phase diagrams magnetic properties

Alloy design by dislocation engineering

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Journal of materials Science & Technology 2018年第3期34卷 417-420页

作者： m.X.Huang b.b.He Department of mechanical Engineering The University of Hong Kong

Ultra-high strength alloys with good ductility are ideal materials for lightweight structural application in various industries. However, improving the strength of alloys frequently results in a reduction in ductility, which is known as the strength-ductility trade-off in metallic materials. Current alloy design strategies for improving the ductility of ultra-high strength alloys mainly focus on the selection of alloy composition （atomic length scale） or manipulating ultra-fine and nano-grained microstructure （grain length scale）. The intermediate length scale between atomic and grain scales is the dislocation length scale. A new alloy design concept based on such dislocation length scale, namely dislocation engineering, is illustrated in the present work. This dislocation engineering concept has been successfully substantiated by the design and fabrication of a deformed and partitioned （D＆P） steel with a yield strength of 2,2 GPa and an uniform elongation of 16%. In this D＆P steel, high dislocation density can not only increase strength but also improve ductility. High dislocation density is mainly responsible for the improved yield strength through dislocation forest hardening, whilst the improved ductility is achieved by the glide of intensive mobile dislocations and well-controlled transformation-induced plasticity （TRIP） effect, both of which are governed by the high dislocation density resulting from warm rolling and martensitic transformation during cold rolling. In addition, the present work proposes for the first time to apply such dislocation engineering concept to the quenching and partitioning （Q＆P） steel by incorporating a warm rolling process prior to the quenching step, with an aim to improve simultaneously the strength and ductility of the Q＆P steel. It is believed that dislocation engineering provides a new promising alloy design strategy for producing novel strong and ductile alloys.

关键词： Alioy design Dislocation engineering D&P steel Q&P steel TRIP Warm rolling