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Journal of Environmental Sciences 2014年第11期26卷 2362-2368页

作者： Kamaraj m. ranjith K.S. rajeshwari Sivaraj rajendra Kumar r.t. Hasna Abdul Salam Department of Biotechnology Dr.N.G.P. Arts and Science College Coimbatore 641048 Tamil Nadu India Advanced materials and Devices Laboratory Department of Physics Bharathiar University Coimbatore 641046 Tamil Nadu India Department of Biotechnology School of Life Sciences Karpagam University Coimbatore 641021 Tamil Nadu India

Photocatalytic degradation of Bisphenol A （BPA）, a representative endocrine disruptor chemical, was carried out under irradiation of sunlight in the presence of CexZn1-xO nanophotocatalyst. Cerium （Ce） ions were successfully incorporated into the bulk lattice of ZnO by simple co-precipitation process. the CexZn1-xO composite nanostructures exhibited higher photocatalytic efficiency than pure ZnO in the degradation of BPA under sunlight irradiation and nearly complete mineralization of BPA was achieved. the degradation rate was strongly dependent on factors such as the size and structure of catalyst, doping material concentration, BPA concentration, catalyst load, irradiation time and pH levels. this work suggested that the CexZn1-xO assisted photocatalytic degradation is a versatile, economic, environmentally benign and efficient method for BPA removal in the aqueous environment.

关键词： Bisphenol A (BPA) ZnO CexZn1-xO Sunlight Co-precipitation Cerium

Algebraic treatment of the mIC-Kepler System in Spherical Coordinates

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Chinese Physics Letters 2007年第8期24卷 2173-2176页

作者： m. t. Chefrour Departement de Physique Institut des Sciences Centre Universitaire de Souk-Ahras Souk-Ahras Algerie

the mIC-Kepler system is studied via the milshtein Strakhovenko variant of the so（2,1） Lie algebra. Green＇s function is constructed in spherical coordinates, with the help of the Kustaanheimo Stiefel variables and the generators of the S0（2,1） group. the energy spectrum and the normalized wavefunctions of the bound states are obtained.

关键词： FIELD

machine Learning models of Plastic Flow Based on representation theory

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Computer modeling in Engineering & Sciences 2018年第12期117卷 309-342页

作者： r.E.Jones J.A.templeton C.m.Sanders J.t.Ostien Sandia National Laboratories P.O.Box 969LivermoreCA 94551USA.

We use machine learning(mL)to infer stress and plastic flow rules using data from representative polycrystalline *** particular,we use so-called deep(multilayer)neural networks(NN)to represent the two response *** mL process does not choose appropriate inputs or outputs,rather it is trained on selected inputs and ***,its discrimination of features is crucially connected to the chosen inputoutput ***,we draw upon classical constitutive modeling to select inputs and enforce well-accepted symmetries and other *** the context of the results of numerous simulations,we discuss the design,stability and accuracy of constitutive NNs trained on typical experimental *** these developments,we enable rapid model building in real-time with experiments,and guide data collection and feature discovery.

关键词： machine learning constitutive modeling plasticity invariance.

Process tolerant and Power Efficient SrAm Cell for Internet of things Applications

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Computers, materials & Continua 2022年第8期72卷 3425-3446页

作者： t.G.Sargunam Lim Way Soong C.m.r.Prabhu Ajay Kumar Singh Faculty of Engineering and technology Multimedia UniversityMelaka75450Malaysia School of Engineering and Computing Manipal International UniversityNilai71800Malaysia Electronics and Communication Engineering Department NIIT UniversityNeemarana301705India

the use of Internet of things(Iot)applications become dominant in many *** on-chip data processing and computations are also increasing *** battery enabled and low leakage memory system at subthreshold regime is a critical requirement for these Iot *** cache memory designed on Static random-Access memory(SrAm)cell with features such as low power,high speed,and process tolerance are highly important for the Iot memory ***,a process tolerant SrAm cell with low power,improved delay and better stability is presented in this research *** proposed cell comprises 11 transistors designed with symmetric approach for write operations and single ended circuit for read operations that exhibits an average dynamic power saving of 43.55%and 47.75%for write and 35.59%and 36.56%for read operations compared to 6 t and 8 t SrAm *** cell shows an improved write delay of 26.46%and 37.16%over 6 t and 8t and read delay is lowered by 50.64%and 72.90%against 6 t and 10 t *** symmetric design used in core latch to improve the write noise margin(WNm)by 17.78%and 6.67%whereas the single ended separate read circuit improves the read Static Noise margin(rSNm)by 1.88x and 0.33x compared to 6 t and 8t *** read power delay product and write power delay product are lower by 1.94x,1.39x and 0.17x,2.02x than 6 t and 8 t cells *** lower variability from 5000 samples validates the robustness of the proposed *** simulations are carried out in Cadence virtuoso simulator tool with Generic Process Design Kit(GPDK)45 nm technology file in this work.

关键词： SrAm cell low power process efficient read stability write ability static noise margin PVt variation internet of things

Influence of LDH conversion coatings on the adhesion and corrosion protection of friction spot-joined AA2024-t3/CF-PPS

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Journal of materials Science & technology 2021年第8期67卷 197-210页

作者： A.C.Bouali N.m.Andre m.r.Silva Campos m.Serdechnova J.F.dos Santos S.t.Amancio-Filho m.L.Zheludkevich Institute of materials research Helmholtz-Zentrum G eesthacht.Magnesium Innovation CentreCorrosion and Surface TechnologyMax-Planck-Straβe 121502 CeesthachtGermany Institute of materials research Helmholtz-Zentrum GeesthachtMaterials MechanicsSolid State Joining ProcessesMax-Planck-Straβe 121502 CeesthachtGermany Graz University of technology-tU Graz Institute of Materials Sciencejoining and FormingBMK Endowed Professorship for AviationKopemikusgasse 24/18010 GrazAustria Faculty of Engineering University of KielKaiserstrasse 224143 KielGermany

Layered double hydroxide(LDH)conversion coatings loaded with corrosion inhibitors were suggested for the surface treatment of the aluminum alloy 2024-t3,prior to friction spot joining with carbon-fiber reinforced polyphenylene sulfide(AA2024-t3/CF-PPS).Vanadate was used as a model corrosion *** shear testing method revealed an increase of approx.20%of the joint’s adhesion performance when treated with LDH and before exposure to salt *** evaluation of the joints after exposure to salt spray demonstrated a significant difference in the corrosion behavior of the joints when the AA2024-t3 is treated with LDH loaded with nitrate and vanadate *** LDH intercalated with nitrate revealed a clear improvement in the mechanical and corrosion resistance performance of the joints,even after 6 weeks of salt ***,the LDH intercalated with vanadate failed in providing protection against corrosion as well as preserving the mechanical properties of the *** effect of the galvanic corrosion was further investigated by zero resistance ammeter(ZrA)measurements as well as localized scanning vibrating electrode technique(SVEt).

关键词： Friction spot joining Layered double hydroxide Galvanic couple Corrosion protection Adhesion

the detrimental effect of autofrettage on externally cracked modern tank gun barrels

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Defence technology（防务技术） 2019年第2期15卷 146-153页

作者： m.Perl t.Saley Pearlstone Center for Aeronautical Engineering Studies Department of Mechanical Engineering Ben-Gurion University of the Negev

Overstraining gun tubes has a twofold advantage. First, it enables the increase of the Safe maximum Pressure(SmP) in the tube, resulting in a higher muzzle velocity which extends the gun's range and its projectile kinetic energy. Second, it reduces the tube's susceptibility to internal cracking which prolongs its fatigue life. Unfortunately, autofrettage also bears an inherent detrimental effect as it considerably increases the tensile hoop stress at the outer portion of the barrel's wall, which enhances external cracking of the tube by increasing the prevailing Stress Intensity Factor(SIF). In order to quantify this disadvantageous effect, 3-D mode I SIFs distributions along the front of a single external radial semielliptical crack initiating from the outer surface of an autofrettaged modern gun barrel, overstrained by either the Swage or the Hydraulic autofrettage processes, are evaluated. the analysis is performed by the finite element(FE) method, using singular elements along the crack front. Innovative residual stress fields(rSFs), incorporating the Bauschinger effect for both types of autofrettage are applied to the ***'s [1] rSF is also applied to the tube for comparison reasons. All three rSFs are incorporated in the FE analysis, using equivalent temperature fields, Values for K_(IA)-the SIF resulting from the tensile residual stresses induced by autofrettage are evaluated for: a typical barrel of radii ratio r_o/r_i = 2, crack depth to wall-thickness ratios(a/t = 0.005-0.1),crack ellipticities(a/c = 0.2-1.0),and five levels of Swage,Hydraulic and Hill's autofrettage(e = 40%,60%,70%,80%,and 100%). In total,375 different 3-D cases are analyzed. the analysis demonstrates undoubtedly the detrimental effect of all types of autofrettage in increasing the prevailing effective stress intensity factor of external cracks, resulting in crack initiation enhancement and crack growth rate acceleration which considerably shortens the total fatigue life of the bar

关键词： Gun barrel Swage and hydraulic autofrettage External crack 3-D Finite element

New methodological Approach to Investigation of Kinetics of rEE Extraction in Nonstationary Conditions

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Journal of rare Earths 2007年第4期25卷 385-391页

作者： Kopyrin A A Fomichev A A Afonin m A todd t A Saint-Petersburg Institute of technology Idaho National Laboratory

the influence of periodical oscillations of the temperature on extraction and stripping processes in the extraction systems was studied. two extraction systems were investigated：（1） 6 mol · L^-1 NaNO3-Nd（NO3）3-Pr（NO3）3-tBP kerosene and （2） [Nd（NO3）3 · 3tBP] -[ Pr（NO3）3 · 3tBP] -kerosene - 0.1 mol · L^-1 HNO3. mathematical modeling of the nonstationary membrane extraction has been enhanced by including the dependence of the extraction rate constants on temperature. the values of activation energy for direct and reverse extraction and stripping reactions of Pr and Nd were calculated from experimental temporal dependencies of metal concentration and temperature by solving the reverse kinetics problem using the proposed mathematical model, A series of experiments with periodical oscillations of the temperature on the extraction system for the separation of rare earth elements （rEE） using bulk liquid membrane between two extractors were performed. the mathematical model adequately describes the experimental data. the optimization of the extraction process for separation of rEE by liquid membrane, under the influence of periodical oscillation of the temperature, was made based on the extraction rate constants and activation energies. the optimal conditions of separation by liquid membrane were found： frequency and amplitude of thermal oscillations, liquid membrane flow rate, and optimal ratio between organic and aqueous phase in extractors.

关键词： kinetics extraction non-stationary rare earths

Influence of residual stresses on failure pressure of cylindrical pressure vessels

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Chinese Journal of Aeronautics 2013年第6期26卷 1415-1421页

作者： m.Jeyakumar t.Christopher Department of mechanical Engineering Sardar Raja College of EngineeringAlangulamTirunelveli 627 808India Department of mechanical Engineering Government College of EngineeringTirunelveli 627 007India

the utilization of pressure vessels in aerospace applications is *** this work,fnite element analysis（FEA）has been carried out using ANSYS software package with 2D axisymmetric model to access the failure pressure of cylindrical pressure vessel made of AStm A36 carbon steel having weld-induced residual *** fnd out the effect of residual stresses on failure pressure,frst an elasto-plastic analysis is performed to fnd out the failure pressure of pressure vessel not having residual *** a thermo-mechanical fnite element analysis is performed to assess the residual stresses developed in the pressure vessel during *** one more elasto-plastic analysis is performed to assess the effect of residual stresses on failure pressure of the pressure vessel having residual *** analysis indicates reduction in the failure pressure due to unfavorable residual stresses.

关键词： Aerospace engineering AStm A36 Finite element analysis Pressure vessels Welding residual stress

Vibration Based tool Insert Health monitoring Using Decision tree and Fuzzy Logic

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Structural Durability & Health monitoring 2019年第3期13卷 303-316页

作者： Kundur Shantisagar r.Jegadeeshwaran G.Sakthivel t.m.Alamelu manghai School of mechanical and Building Sciences Vellore Institute of TechnologyChennaiTamil NaduIndia

the productivity and quality in the turning process can be improved by utilizing the predicted performance of the cutting *** research incorporates condition monitoring of a non-carbide tool insert using vibration analysis along with machine learning and fuzzy logic approach.A non-carbide tool insert is considered for the process of cutting operation in a semi-automatic lathe,where the condition of tool is monitored using vibration *** vibration signals for conditions such as heathy,damaged,thermal and flank were acquired with the help of piezoelectric transducer and data acquisition *** descriptive statistical features were extracted from the acquired vibration signal using the feature extraction *** extracted statistical features were selected using a feature selection process through J48 decision tree *** selected features were classified using J48 decision tree and fuzzy to develop the fault diagnosis model for the improved predictive *** decision tree model produced the classification accuracy as 94.78%with five selected *** developed fuzzy model produced the classification accuracy as 94.02%with five membership ***,the decision tree has been proposed as a suitable fault diagnosis model for predicting the tool insert health condition under different fault conditions.

关键词： Statistical features J48 decision tree algorithm confusion matrix fuzzy logic weka

A Flexible Fin with Bio-Inspired Stiffness Profile and Geometry

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Journal of Bionic Engineering 2011年第4期8卷 418-428页

作者： t. Salumae m. Kruusmaa Centre for Biorobotics Tallinn University of Technology Akadeemia tee 15A-111 12618 Tallinn Estonia

Biological evidence suggests that fish use mostly anterior muscles for steady swimming while the caudal part of the body is passive and, acting as a carrier of energy, transfers the momentum to the surrounding water. Inspired by those findings we hypothesize that certain swimming patterns can be achieved without copying the distributed actuation mechanism of fish but rather using a single actuator at the anterior part to create the travelling wave. to test the hypothesis a pitching flexible fin made of silicone rubber and silicone foam was designed by copying the stiffness distribution profile and geometry of a rainbow trout. the kinematics of the fin was compared to that of a steadily swimming trout. Fin＇s propulsive wave length and tail-beat am- plitude were determined while it was actuated by a single servo motor. results showed that the propulsive wave length and tail-beat amplitude of a steadily swimming 50 cm rainbow trout was achieved with our biomimetic fin while stimulated using certain actuation parameters （frequency 2.31 Hz and amplitude 6.6 degrees）. the study concluded that fish-like swimming can be achieved by mimicking the stiffness and geometry of a rainbow trout and disregarding the details of the actuation mechanism.

关键词： biomimetics stiffness profile fin robotics fish