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Paraconductivity study in Erba_2Cu_(3-x)M_xO_(7-δ)(M=Zn, Fe) superconductors

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Chinese Physics b 2013年第11期22卷 562-568页

作者： A.sedky s.b.Mohamed Physics Department Faculty of Science King Faisal University Physics Department Faculty of Science Assiut University

We report here the paraconductivity of Erba2Cu3-xMxO7-δ （M = Zn and Fe） superconductors. The logarithmic plots of excess conductivity Δσ and reduced temperature C reveal two different exponents corresponding to crossover temperature as a result of shifting the order parameter from 2 to 3. The first exponent in the normal field region is close to 1, in which the order parameter dimensionality （OPD） is 2. The second exponent in the critical field region is close to 0.5, in which the OPD is 3. The coherence length, interlayer coupling, interlayer separation and carrier concentration decrease with increasing doping content, and their values for Fe samples are different from those of Zn samples. While anisotropy is increased with increasing doping content, it is generally higher for a Zn sample than that for an Fe sample. We also estimate several physical parameters such as upper critical magnetic fields in the a–b plane and along the c axis （bab and bc）, and critical current density J at 0 K. Although bab and bc are generally increased with doping content increasing, the value of bab is found to be twice more than that of bc. A similar behavior is obtained for J （0 K） and its value is higher in the Fe sample than that in the Zn sample. These results are discussed in terms of oxygen deficiency, localization of carriers, and flux pinning, which are produced by doping.

关键词： ceramics chemical synthesis X-ray diffraction electrical properties transport properties

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

spin texturing in quantum wires with Rashba and Dresselhaus spin-orbit interactions and in-plane magnetic field

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Chinese Physics b 2016年第1期25卷 750-756页

作者： b Gisi s sakiroglu I sokmen Physics Department Graduate School of Natural and Applied SciencesDokuz Eyll Universityizmir 35390Turkey Physics Department Faculty of ScienceDokuz Eyll Universityizmir 35390Turkey

In this work, we investigate the effects of interplay of spin-orbit interaction and in-plane magnetic fields on the electronic structure and spin texturing of parabolically confined quantum wire. Numerical results reveal that the competing effects between Rashba and Dresselhaus spin--orbit interactions and the external magnetic field lead to a complicated energy spectrum. We find that the spin texturing owing to the coupling between subbands can be modified by the strength of spin- orbit couplings as well as the magnitude and the orientation angle of the external magnetic field.

关键词： spin-orbit coupling quantum wire spin texture

Flow of colloidal suspension and irreversibility analysis with aggregation kinematics of nanoparticles in a microchannel

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Applied Mathematics and Mechanics(English Edition) 2020年第11期41卷 1671-1684页

作者： s.sINDHU b.J.GIREEsHA Department of studies and Research in Mathematics Kuvempu UniversityShankaraghattaShivamogga 577451KarnatakaIndia

The current exploration focuses on the ethylene glycol(EG)based nanoliquid flow in a *** effectiveness of the internal heat source and linear radiation is reflected in the present *** estimation of suitable thermal conductivity model has affirmative impact on the convective heat transfer *** examination is conceded with the nanoparticle aggregation demonstrated by the Maxwell-bruggeman and Krieger-Dougherty models which tackle the formation of *** models effectively describe the thermal conductivity and viscosity *** dimensionless mathematical expressions are solved numerically by the Runge Kutta Fehlberg approach.A higher thermal field is attained for the bruggeman model due to the formation of thermal bridge.A second law analysis is carried out to predict the sources of irreversibility associated with the thermal *** is remarked that lesser entropy generation is obtained for the aggregation *** entropy generation rate declines with the slip flow and the thermal heat flux.A notable enhancement in the bejan number is attained by increasing the biot *** is established that the nanoparticle aggragation model exhibits a higher bejan number in comparision with the usual flow model.

关键词： nanoparticle aggregation nanoliquid microchannel slip parameter heat flux

Earth return path impedances of underground cable for three-layer earth

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2009年第8期10卷 1191-1198页

作者： b.HEMMATIAN b.VAHIDI s.H.HOssEINIAN Department of Electrical Engineering Amirkabir University of Technology

One of the factors that affect the parameters of an underground cable is earth return path *** developed a formula for the case of one-layer(homogenous) *** in practice the earth is composed of several *** this study we develop a new formula for earth return path impedance in the case of a three-layer *** check the accuracy of the obtained results,a comparison has been made with the finite element method(FEM).A comparison between the results of the Pollaczek formula and results of the obtained formula for a three-layer earth has been made,showing that the use of the Pollaczek formula instead of the actual formula can cause serious errors.

关键词： Underground cables Earth return path impedance Earth stratification Finite element method (FEM)

Dye reduction-based electron-transfer activity monitoring assay for assessing microbial electron transfer activity of microbial fuel cell inocula

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Journal of Environmental sciences 2020年第10期32卷 171-177页

作者： Kartik s.Aiyer Roshan Rai b.s.Vijayakumar Department of biosciences Sri Sathya Sai Institute of Higher LearningPrasanthi NilayamPuttaparthiAndhra Pradesh-515134India

Microbial fuel cells (MFC) utilize microbes as catalysts to convert chemical energy to *** used for MFC operation must therefore contain active microbial *** dye reduction-based electron-transfer activity monitoring (DREAM) assay was employed to evaluate different inocula used in MFCs for their microbial bioelectrical *** assay utilizes the redox property of Methylene blue to undergo color change from blue to colorless state upon microbial *** extent of Methylene blue reduction was denoted as the DREAM assay *** assay was initially performed on a microbial culture along with the growth curve and estimation of colony forming units (CFUs).DREAM coefficient correlated to the CFU/m L obtained over time as growth *** assay was then extended to water samples (domestic sewage,lake and a man-made pond) serving as inocula in *** wastewater gave the highest DREAM coefficient (0.300±0.05),followed by pond (0.224±0.07) and lake (0.157±0.04) water *** density obtained conformed to the DREAM coefficient values,with the three samples generating power densities of 46.45±5.1,36.12±3.2 and 25.08±4.3 m W/m^2 *** have also studied the role of addition of various carbon sources and their concentrations towards improving the sensitivity of the *** DREAM assay is a rapid,easy-to-perform and cost-effective method to assess inocula for their suitability as anolytes in terms of electron transfer potential in MFCs.

关键词： Dye reduction Electron transfer Methylene blue Microbial fuel cell Wastewater

Effect of bagasse ash reinforcement on the wear behaviour of Al-Cu-Mg/bagasse ash particulate composites

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Acta Metallurgica sinica(English Letters) 2010年第2期23卷 81-89页

作者： V.s. Aigbodion s.b. Hassan G.b. Nyior T. Ause Department of Metallurgical and Materials Engineering Ahmadu Bello University

The effect of bagasse ash （bAp） particle reinforcement on the wear behavior of Al-Cu- Mg alloy has been studied. bagasse ash particles were varied from 0 wt pct-10 wt pct with interval of 2 wt pct. Unlubricated pin-on disc tests were conducted to examine the wear behaviour of the aluminium alloy/bagasse ash particulate composites. The tests were conducted at varying loads, from 5 to 20 N and sliding speeds of 1.26 m/s, 2.51 m/s, 3.77 m/s and 5.02 m/s for a constant sliding distance of 5000 m. The results showed that the wear rates of the A1-Cu-Mg/bAp composites are lower than that of the matrix alloy and further decrease with increasing bagasse ash content. Wear rate increases as the sliding speed and applied load increase. The microstructure of the worn surface revealed that a large amount of plastic deformation appeared on the surface of the unreinforced alloy. While bagasse ash reinforced Al-Cu-Mg alloy showed worn out surface that is not smooth, and grooves, scratches and parallel lines were observed. A combination of adhesion and delamination wear was in operation. These results show that improve wear properties is achievable for the aluminium alloy by the addition of bagasse ash particles as reinforcement material.

关键词： Al-Cu-Mg alloy bagasse ash Composites Load sliding speed and Wear

Quantized autoencoder(QAE)intrusion detection system for anomaly detection in resource-constrained loT devices using RT-loT2022 dataset

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Cybersecurity 2024年第2期7卷 13-27页

作者： b s sharmila Rohini Nagapadma Depatment of Electronics and Communication Engineering The National Institute of EngineeringMysoreKarnataka 570008India

In recent years,many researchers focused on unsupervised learning for network anomaly detection in edge devices to identify *** deployment of the unsupervised autoencoder model is computationally expensive in resource-constrained edge *** study proposes quantized autoencoder(QAE)model for intrusion detection systems to detect *** is an optimization model derived from autoencoders that incorporate pruning,clustering,and integer quantization *** autoencoder uint8(QAE-u8)and quantized autoencoder float16(QAE-f16)are two variants of QAE built to deploy computationally expensive Al models into Edge ***,we have generated a Real-Time Internet of Things 2022 dataset for normal and attack *** autoencoder model operates on normal traffic during the training *** same model is then used to reconstruct anomaly traffic under the assumption that the reconstruction error(RE)of the anomaly will be high,which helps to identify the ***,we study the performance of the autoencoders,QAE-u8,and QAE-f16 using accuracy,precision,recall,and F1 score through an extensive experimental *** showed that QAE-u8 outperforms all other models with a reduction of 70.01%in average memory utilization,92.23%in memory size compression,and 27.94%in peak CPU ***,the proposed QAE-u8 model is more suitable for deployment on resource-constrained IoT edge devices.

关键词： IoT constrained system

Achieving better NO_x Removal in Discharge Plasma Reactor by Field Enhancement

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维普期刊数据库

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Plasma science and Technology 2008年第2期10卷 198-202页

作者： b.s.RAJANIKANTH Dipanwita sINHA High Voltage Laboratory Deptartment of Electrical Engineering Indian Institute of Science Bangalore 560012 India

Application of plasma chemistry for gas cleaning is gaining prominence in recent years, mainly from an energy efficiency point of view. In this paper we conducted a comparative study of NO/NOx removal using two different types of dielectric barrier discharge electrodes, wire- cylinder reactor, pipe-cylinder reactor. Investigations were first carried out with synthetic gases to obtain the baseline information on the NO/NOx removal with respect to the two geometries studied. Further, experiments were carried out with raw diesel exhaust under loaded condition. A high NOx removal efficiency of 90% was observed for the pipe-cylinder reactor as compared to that of 53.4% for the wire-cylinder reactor. Furthermore, for the same energy consumed per NO molecule （about 73 eV/NO molecule）, the removal efficiency increased from 67% for the wire- cylinder to about 98% for the pipe-cylinder which was quite appreciable.

关键词： NOx removal engine exhaust plasma treatment barrier discharge electrodes