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A novel chaotic butterfly network topology based block scrambling and crown graph based bit-wise diffusion for image encryption

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Frontiers of Computer Science 2021年第2期15卷 193-195页

作者： Vidhya r Brindha m Department of Computer Science and Engineering National Institute of TechnologyTamilnadu620015India

1 Introduction and contributions Due to,rapid growth in multimedia and internet technology,multimedia information such as images,videos,etc are shared via *** the confidentiality of information i.e,information security has become more *** this purpose,different techniques are approached in order to achieve confidentiality of *** traditional symmetric encryption techniques like AES[1],DES confidentiality can be *** encryption schemes like DES and AES which are private key encryption methods and other public key methods like rSA(rivest Shamir Adleman)algorithm are time consuming.

关键词： multimedia encryption network

Comparative orotomy of the Archean Superior and Phanerozoic Altaid orogenic systems

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National Science review 2023年第2期10卷 20-48页

作者： Timothy m.Kusky A.m.Celal ?eng?r Center for Global Tectonics School of Earth Sciences and State Key Laboratory for Geological Processes and Mineral ResourcesChina University of Geosciences Badong National Observatory and research Station for Geohazards Ministry of Education China University of Geosciences Department of Geological Engineering Middle East Technical University Eurasia Institute of Earth Sciences Istanbul Technical University Department of Geology Faculty of Mines Istanbul Technical University

We compare and contrast the materials and mechanisms of continental crustal growth in the largest preserved regions of Phanerozoic and Archean juvenile additions to the crust,to test for similarities or differences in the formation of continents through *** accomplish this through a comparison of map patterns,lithological contents,and structural and metamorphic evolution of the Phanerozoic Altaid orogenic system of Asia,with the Archean Superior Province of the North American Craton,using a method termed comparative *** orogenic systems consist of collages of curvilinear belts of eroded arcs,some older continental slivers,and vast tracts of former subduction/accretionary *** contain numerous shreds of portions of the ophiolite suite,slivers of island and continental arcs,and accreted oceanic plateau,all intruded by multiple magmatic suites during or between multiple deformation events,then sliced by large transcurrent fault systems and bent into large oroclinal *** make this comparison because the Superior Province is a typical Archean craton that was later,in the P aleoproterozoic,incorporated into the larger North American Craton,and has occupied a central position in several super continents(*** and Nuna,which then formed the core of Columbia,rodinia,Laurentia and Pangea) during its *** it is the largest single fragment of Archean continental cratonic lithosphere preserved on Earth,the Superior Province is widely regarded as a testing ground for how Earth’s continental crust was ***,the Altaids encompass the largest region of crustal growth for the *** comparison with the Altaids is needed,as in recent years many myths about how the planet may have responded to higher heat production and flow in the Archean have emerged,because of trends in the science where regional geology is ignored in favor of numerical models,isotopic proxies for assumed models of chemical behavior for crust-for

关键词： Altaids superior province ophiolite subduction strike-slip

Improved Non-Covalent Biofunctionalization of multi-Walled Carbon Nanotubes Using Carbohydrate Amphiphiles with a Butterfly-Like Polyaromatic Tail

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Nano research 2010年第11期3卷 764-778页

作者： mohyeddin Assali manuel Pernía leal Inmaculada Fernández Pablo romero-Gomez rachid Baati Noureddine Khiar Instituto de Investigaciones Químicas C.S.I.C-Universidad de Sevillac/.Américo Vespucio49Isla de la CartujaSevilla 41092Spain Departamento de Química Orgánica y Farmacéutica Facultad de FarmaciaUniversidad de SevillaSevilla 41012Spain Instituto de Ciencias de materiales de Sevilla C.S.I.C-Universidad de Sevillac/.Américo Vespucio49Isla de la CartujaSevilla 41092Spain Universitéde Strasbourg Facultéde Pharmacie CNrS/Umr 7199 Laboratoire des Systèmes Chimiques Fonctionnels BP 6002474 route du Rhin67400 IllkirchFrance

We have developed an efficient strategy for the non-covalent functionalization of multi-walled carbon nanotubes(mWCNTs)which allows a biomimetic presentation of carbohydrates on their surface byπ-πstacking *** strategy is based on the use of sugar-based amphiphiles functionalized with tetrabenzo[a,c,g,i]fluorene(Tbf),a polyaromatic compound with a topology that resembles a butterfly with open *** new carbohydrate-tethered Tbf amphiphiles have been synthesized in a straightforward manner using click *** reported method has been developed in order to improve the rather low ability of pyrene-based systems to exfoliate mWCNTs in *** means of thermogravimetric analysis(TGA),ultraviolet(UV),infrared(Ir),and fluorescence spectroscopies the interaction between mWCNTs and the Tbf group has been found to be stronger than those involving pyrene-based amphiphilic *** resulting aggregates with a multivalent sugar exposition on their surface are able to engage in specific ligand-lectin interactions similar to glycoconjugates on a cell membrane.

关键词： Carbon nanotubes non-covalent functionalization tetrabenzo[a c g i]fluorene carbohydrates click chemistry biocompatible system

Quantification of the mixture of Hydrothermal and Fresh Water in Tectonic Valleys

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Journal of Earth Science 2020年第5期31卷 1007-1015页

作者： Janete moran-ramirez Jose Ivan morales-Arredondoc maria Aurora Armienta-Hernandez Jose Alfredo ramos-leal National Council of Science and Technology National Autonomous University of MexicoInstitute of GeophysicsScientific Research CircuitUniversity CityCoyoacan 04150Mexico CityMexico National Autonomous University of mexico Institute of GeophysicsUniversity CampusMexico CityMexico Potosino Institute for Scientific and Technological research 78216 San Luis PotosiS.L.P.Mexico

This study was conducted to identify the origin, hydrogeochemical processes and evolution of groundwater in a tectonic valley. This study was carried out with the aim of quantifying the proportions of groundwater flows contributing to the water chemistry abstracted in a zone of convergence favored by the presence of active faults. The study area is located in the Trans-mexican Volcanic Belt. End members methodology was applied to identify the mixing of hydrothermal with fresh groundwater, where changes in the aquifer geology result in distinct groundwater chemical signatures. Ternary mixing was quantified using conservative elements. moreover, other evolutionary processes, such as ion exchange and silicate weathering occur due to changes in the geology of the area. In ternary mixing, each of the end members is associated with the lithology through which it circulates. The local flow contributes 70% of the water to the system, the intermediate flow contributes 14%, and the regional flow contributes 16%. Three types of water are produced: Na-HCO3, due to the interaction of water with volcanic rocks of rhyolitic composition, Na-mg-HCO3, due to the interaction of water with volcanic rocks of basaltic-andesite composition, and Ca-HCO3, due to the interaction of water with sedimentary calcareous rocks.

关键词： hydrogeochemistry ternary mixing end members conservative elements local flow mexico

Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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Neural regeneration research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-merz Jorge Hernández-Campano Sergei A.Kirov Jesús m.Hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain ramón y Cajal Institute for Health research(IrYCIS) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and regenerative medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

Cross-focusing of two chirped Gaussian laser beams and THz wave generation in plasmas of multi-ion species under a weakly relativistic and ponderomotive regime

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Plasma Science and Technology 2022年第10期24卷 1-11页

作者： m r JAFArI mILANI S rEZAEI m J JAFArI Photonics and Quantum Technologies research School Nuclear Science and Technology Research InstituteTehran 14665-678Iran Plasma and Fusion research School Nuclear Science and Technology Research InstituteTehran 14399-51113Iran

The generation of terahertz(THz)waves via the beating of two high-intensity chirped Gaussian lasers in a multi-ion-species plasma is numerically studied by taking into account the weak relativistic and ponderomotive regime of *** coupled differential equations for beamwidth parameters are extracted by introducing the dielectric function of such plasma and using WKB and paraxial ray *** amplitude of THz radiation at beat frequency resulting from the nonlinear current density induced by the beat ponderomotive force of the cross-focusing of beams was *** impacts of the chirp frequency parameter,initial laser intensity and initial ionic species density(specifically,the presence of singly and doubly charged ions)in the plasma on THz generation were *** numerical results reveal that THz radiation generation strongly depends on the chirp frequency parameter.A specific range of chirp frequencies exists for self-focusing as well as THz generation with a'turning point',where the THz emission reaches its maximum *** results show that the strength of self-focusing and consequently the generated THz radiation are reduced by increasing the density of doubly charged ionic species in the plasma due to the suppression of the nonlinear effects.

关键词： laser–plasma interaction THz generation chirped Gaussian laser beams

On Connected Tetravalent Cayley Graphs of a Non-abelian Group of Order 3p2

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Algebra Colloquium 2017年第3期24卷 467-480页

作者： m.r. Darafsheh m. Abdollahi School of mathematics Statistics and Computer Science College of Science University of Tehran Tehran Iran

In this paper we determine all tetravalent Cayley graphs of a non-abelian group of order 3p2, where p is a prime number greater than 3, and with a cyclic Sylow p-subgroup. We show that all of these tetravalent Cayley graphs are normal. The full automorphism group of these Cayley graphs is given and the half-transitivity and the arc-transitivity of these graphs are investigated. We show that this group is a 5-CI-group.

关键词： Cayley graph automorphism group tetravalent graph half-transitive arctransitive m-CI-group

Analysis of surface roughness of rock dust reinforced AA6061-mg matrix composite in turning

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Journal of magnesium and Alloys 2021年第5期9卷 1686-1693页

作者： r.Balachandhar r.Balasundaram m.ravichandran Department of mechanical Engineering Pavender Barathidasan College of Engineering and TechnologyTiruchirappalli620024Tamil NaduIndia Department of mechanical Engineering K.Ramakrishnan College of EngineeringTiruchirappalli621112Tamil NaduIndia Department of mechanical Engineering SRM Institute of Science and TechnologyTiruchirappalli Campus621105Tamil NaduIndia

This work,examines the Surface roughness(Sr)of composite consisting Aluminium alloy(AA6061),magnesium and rock dust during turning *** study the performance,three different test specimens with different constituents of Al 6061-T6,AZ31 and rock dust were prepared by stir casting *** experiments were carried out using mTAB Siemens-CNC *** input parameters for machining are speed,depth of cut&feed and output response is surface roughness For each test specimen,there are 15 turning operations were performed using Box-Ben hen Design *** analyze the process parameters for Sr,the models of ANOVA and Decision Tree(DT)algorithms were *** algorithms are confirmed that,speed is the most significant factor for *** addition of AZ 31 with 1%and rock dust of 2%in AA6061 produced better surface *** models of linear regression,multilayer perception and support vector regression from data science were formulated to find the relationship between *** these models multi layer perception produced minimum root mean square error.

关键词： Composite Turning Surface roughness Anova Decision tree regression

Computer modelling of metal Dissolution in the Presence of Aqueous Electrolyte

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Chinese Physics Letters 2002年第3期19卷 389-390页

作者： r.I.Eglitis m.r.Philpott UniversitatOsnabruck FachbereichPhysikD-49069OsnabruckGermany DepartmentofmaterialsScience NationalUniversityofSingapore10KentRidgeCrescentSingapore119260

The semi-empirical Hartree-Fock intermediate neglect of differential overlap (INDO) method was used to explore the potential energy surface of adsorbed water molecules and to speculate, using fairly simple cluster models, on the reaction path followed by metal ions leaving the surface. As an example, INDO calculations were used to calculate the potential energy curve for a metal atom leaving the surface and entering into a solvation cage composed of tetrahedral arranged water molecules. The effect of adding a NaCl ion pair to the system with the halide ion above the dissolving atom was also explored.

关键词： metals