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Analytical solution approach for nonlinear buckling and postbuckling analysis of cylindrical nanoshells based on surface elasticity theory

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Applied Mathematics and Mechanics(English Edition) 2016年第7期37卷 903-918页

作者： r.ANSArI t.POUrASHrAF r.GHOLAMI H.rOUHI Department of Mechanical Engineering University of Guilan Department of Mechanical Engineering Lahijan BranchIslamic Azad University Department of Engineering Science Faculty of Technology and Engineering East of GuilanUniversity of Guilan

the size-dependent nonlinear buckling and postbuckling characteristics of circular cylindrical nanoshells subjected to the axial compressive load are investigated with an analytical approach. the surface energy effects are taken into account according to the surface elasticity theory of Gurtin and Murdoch. the developed geometrically nonlinear shell model is based on the classical Donnell shell theory and the von Karman＇s hypothesis. With the numerical results, the effect of the surface stress on the nonlinear buckling and postbuckling behaviors of nanoshells made of Si and Al is studied. Moreover, the influence of the surface residual tension and the radius-to-thickness ratio is illustrated. the results indicate that the surface stress has an important effect on prebuckling and postbuekling characteristics of nanoshells with small sizes.

关键词： cylindrical nanoshell surface stress nonlinear buckling postbuckling analytical method

Effect of ethanedioic acid functionalization on Ni/Al_2O_3 catalytic hydrodeoxygenation and isomerization of octadec-9-enoic acid into biofuel: kinetics and Arrhenius parameters

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Journal of Energy Chemistry 2016年第1期25卷 158-168页

作者： Olumide Bolarinwa ayodele Kallidanthiyil Chellappan Lethesh Zahra Gholami Yoshimitsu Uemura Centre for Biofuel and Biochemical research Universiti Teknologi PETRONAS Department of Chemical Engineering Faculty of Engineering University of Malaya Centralized Analytical Laboratory Universiti Teknologi PETRONAS

the effect of ethanedioic acid（Ed A） functionalization on Al2O3 supported Ni catalyst was studied on the hydrodeoxygenation（HDO）, isomerization, kinetics and Arrhenius parameters of octadec-9-enoic acid（OA） into biofuel in this report. this was achieved via synthesis of two catalysts; the first, nickel alumina catalyst（Ni/Al2O3） was via the incorporation of inorganic Ni precursor into Al2O3; the second was via the incorporation nickel oxalate（Ni Ox） prepared by functionalization of Ni with Ed A into Al2O3 to obtain organometallic Ni Ox/Al2O3 catalyst. their characterization results showed that Ni species present in Ni/Al2O3 and Ni Ox/Al2O3 were 8.2% and 9.3%, respectively according to the energy dispersive X-ray result. Ni Ox/Al2O3 has comparably higher Ni content due to the Ed A functionalization which also increases its acidity and guarantees high Ni dispersion with weaker metal-support-interaction leading to highly reducible Ni as seen in the X-ray diffraction, X-ray photoelectron spectroscopy, tPr and raman spectroscopy results. their activities tested on the HDO of OA showed that Ni Ox/Al2O3 did not only display the best catalytic and reusability abilities, but it also possesses isomerization ability due to its increased acidity. the Ni Ox/Al2O3 also has the highest rate constants evaluated using pseudo-first-order kinetics,but the least activation energy of 176 k J/mol in the biofuel formation step compared to 244 k J/mol evaluated when using Ni/Al2O3. the result is promising for future feasibility studies toward commercialization of catalytic HDO of OA into useful biofuel using organometallic catalysts.

关键词： Octadec-9-enoic acid Hydrodeoxygenation Isomerization Nickel oxalate Biofuel

Light Weight Cryptographic Address Generation(LW-CGA) Using System State Entropy Gathering for IPv6 Based MANEts

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China Communications 2017年第9期14卷 114-126页

作者： reshmi t.r Murugan K VIt University Anna University

In IPv6 based MANEts, the neighbor discovery enables nodes to self-configure and communicate with neighbor nodes through autoconfiguration. the Stateless address autoconfiguration(SLAAC) has proven to face several security issues. Even though the Secure Neighbor Discovery(SeND) uses Cryptographically Generated Addresses(CGA) to address these issues, it creates other concerns such as need for CA to authenticate hosts, exposure to CPU exhaustion attacks and high computational intensity. these issues are major concern for MANEts as it possesses limited bandwidth and processing power. the paper proposes empirically strong Light Weight Cryptographic Address Generation(LW-CGA) using entropy gathered from system states. Even the system users cannot monitor these system states; hence LW-CGA provides high security with minimal computational complexity and proves to be more suitable for MANEts. the LW-CGA and SeND are implemented and tested to study the performances. the evaluation shows that LW-CGA with good runtime throughput takes minimal address generation latency.

关键词： IPv6 SLAAC EUI-64 CGA SEND system states MANEts

Production of Cellulase and Xylanase by Aspergillus terreus KJ829487 Using Cassava Peels as Subtrates

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Advances in Microbiology 2016年第7期6卷 502-511页

作者： Afolake Atinuke Olanbiwoninu Sunday ayodele Odunfa Department of Biological Sciences Faculty of Natural Sciences Ajayi Crowther University Oyo Nigeria Department of Microbiology Faculty of Sciences University of Ibadan Ibadan Nigeria

Cassava (Manihot esculenta, Crantz) is one of the most important food plants in West Africa. Its peels are made up of cellulose, hemicellulose and lignin. this lignocellulolytic biomass can be converted using microbial enzymes to fermentable sugars which have wide range of biotechnological relevance in many fermentation processes. the aim of this study is to screen filamentous fungi from decaying cassava peels that are good producers of xylanases and cellulases. Decaying parts of cassava peels were obtained and brought to the laboratory for further work. Fungi were isolated, identified and screened for cellulase and xylanase production. Isolate with highest frequency of occurrence and enzyme production was identified using phenotypic and molecular method. Optimisation of growth conditions for enzymes production was monitored using the DNSA method, also saccharification of cassava peel were carried out using the enzymes obtained from the isolate. Aspergillus terreus KJ829487 was the predominant fungus. It produces cellulases and xylanases optimally at 40°C, pH 6 and 8, utilising carboxymethylcellulose (CMC) or xylose and yeast extracts as its carbon and nitrogen sources respectively. Saccharification of the peels yielded 584 mg/L glucose, 78 mg/L xylose and 66 mg/L rhamnose. Aspergillus terreus KJ829487 obtained from cassava peels have the ability to produce high concentration cellulases and xylanases which effectively hydrolysed the lignocelluloses’ biomass to fermentable sugars.

关键词： Cassava Peels Aspergillus terreus Cellulase Xylanase Lignocelluloses Fermentable Sugars

Model development for analyzing 2DEG sheet charge density and threshold voltage considering interface DOS for AlInN/GaN MOSHEMt

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Journal of Semiconductors 2014年第10期35卷 26-29页

作者： Devashish Pandey t.r.Lenka Department of Electronics and Communication Engineering National Institute of Technology Silchar

A model predicting the behavior of various parameters, such as 2DEG sheet charge density and thresh- old voltage, with the variation of barrier thickness and oxide thickness considering interface density of states is presented. the mathematical dependence of these parameters is derived in conjunction with the interface density of states. the dependence of sheet charge density with the barrier thickness and with the oxide thickness is plotted and an insight into the barrier scaling properties of AIInN based MOSHEMts is presented. the threshold voltage is also plotted with respect to barrier thickness and oxide thickness, which reveals the possibility of the enhance- ment mode operation of the device at low values of the interface DOS. the results are in good agreement with the fabricated device available in the literature.

关键词： DOS AIlnN MOSHEMt 2DEG barrier scaling

Conservation laws,Lie symmetries,self adjointness,and soliton solutions for the Selkov–Schnakenberg system

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Communications in theoretical Physics 2024年第2期76卷 29-44页

作者： Kashif Ali Aly r Seadawy Syed t r rizvi Noor Aziz Department of Mathematics COMSATS University IslamabadLahore CampusPakistan Mathematics Department Faculty of ScienceTaibah UniversityAl-Madinah Al-Munawarah41411Saudi Arabia

In this article,we explore the famous Selkov–Schnakenberg(SS)system of coupled nonlinear partial differential equations(PDEs)for Lie symmetry analysis,self-adjointness,and conservation ***,miscellaneous soliton solutions like dark,bright,periodic,rational,Jacobian elliptic function,Weierstrass elliptic function,and hyperbolic solutions of the SS system will be achieved by a well-known technique called sub-ordinary differential *** these results are displayed graphically by 3D,2D,and contour plots.

关键词： Selkov-Schnakenberg system Lie symmetry analysis conservation laws adjointness integrability

A Convolutional Neural Network Classifier VGG-19 Architecture for Lesion Detection and Grading in Diabetic retinopathy Based on Deep Learning

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Computers, Materials & Continua 2021年第1期66卷 827-842页

作者： V.Sudha t.r.Ganeshbabu Department of Electronics and Communication Engineering Pavai College of TechnologyNamakkal637018India Department of Electronics and Communication Engineering Muthayammal Engineering CollegeRasipuram637408India

Diabetic retinopathy(Dr)is a type of disease in eyes as a result of a diabetic condition that ends up damaging the retina,leading to blindness or loss of *** and physiological retinal variations involving slowdown of blood flow in the retina,elevation of leukocyte cohesion,basement membrane dystrophy,and decline of pericyte cells,*** Dr in its initial stage has no symptoms,early detection and automated diagnosis can prevent further visual *** this research,using a Deep Neural Network(DNN),segmentation methods are proposed to detect the retinal defects such as exudates,hemorrhages,microaneurysms from digital fundus images and then the conditions are classified accurately to identify the grades as mild,moderate,severe,no PDr,PDr in ***,saliency detection is applied on color images to detect maximum salient foreground objects from the ***,structure tensor is applied powerfully to enhance the local patterns of edge elements and intensity changes that occur on edges of the ***,active contours approximation is performed using gradient descent to segment the lesions from the ***,the output images from the proposed segmentation process are subjected to evaluate the ratio between the total contour area and the total true contour arc length to label the classes as mild,moderate,severe,No PDr and *** on the computed ratio obtained from segmented images,the severity levels were ***,statistical parameters like the mean and the standard deviation of pixel intensities,mean of hue,saturation and deviation clustering,are estimated through K-means,which are computed as features from the output images of the proposed segmentation *** these derived feature sets as input to the classifier,the classification of Dr was ***,a VGG-19 deep neural network was trained and tested using the derived feature sets from the KAGGLE fundus image dataset containing 35,126 images in

关键词： Diabetic retinopathy saliency map structure tensor gradient descent method exudates haemorrhages microaneurysms VGG-19

SOME EXACt SOLUtIONS OF 3-DIMENSIONAL ZErO-PrESSUrE GAS DYNAMICS SYStEM

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Acta Mathematica Scientia 2011年第6期31卷 2107-2121页

作者： K.t. Joseph Manas r. Sahoo School of Mathematics Tata Institute of Fundamental Research

the 3-dimensional zero-pressure gas dynamics system appears in the modeling for the large scale structure formation in the universe. the aim of this paper is to construct spherically symmetric solutions to the system. the radial component of the velocity and density satisfy a simpler one dimensional problem. First we construct explicit solutions of this one dimensional case with initial and boundary conditions. then we get special radial solutions with different behaviours at the origin.

关键词： zero-pressure gas dynamics spherically symmetric solutions

Synthesis and Characterization of Crosslinked Hydrogel of Konkoli (Maesopsis eminii) Grafted Polymethylacrylamide for a Preliminary Study as an Insulin Delivery System

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Journal of Biosciences and Medicines 2016年第11期4卷 36-47页

作者： Okoko Barth Ugwu Jeffery t. Barminas Iliya I. Nkafamiya ayodele Akinterinwa Modibbo Adma University of technology Yola Nigeria

Polysaccharide has lately received a significant attention in the formulation of drug delivery system based on the abundant availability, non-toxicity and the various ways its nature, structure and functionality can be modified. In this preliminary work on Konkoli (Maesopsis eminii) galactomannan (KG), it was modified by grafting with methacrylamide (MAAm) using ammonium persulphate (ASP) as initiator. the grafted galactomannan was then crosslinked using N, N-methylenebisacrylamide (N, N-MBAAm) to produce the hydrogel called konkoli grafted polymethylacrylamide (KG-g-poly (MAAm)). FtIr analyses confirm crosslinking and other changes in the functionality of KG-g-poly (MAAm) compared to KG. Swelling properties which are fundamental to the potential properties of any hydrogel as a drug delivery system were studied for KG-g-poly (MAAm) with varied amount of monomer (MAAm), crosslinker and pH with respect to time and temperature. there was a rapid rise followed by a dramatic fall in the swelling capacity with increase in both monomer and crosslinker concentration. the swelling capacity of KG-g-poly (MAAm) also improves as the pH of the medium was changed from acidic to alkaline. Generally, the swelling capacity of KG-g-poly (MAAm) increases with time and temperature of immersion. this result therefore encourages further studies as it presents KG-g-poly (MAAm) potentials in such application as insulin delivery system.

关键词： Konkoli (Maesopsis eminii) Galactomannan Hydrogels Konkoli Grafted Polymethylacrylamide (KG-g-poly (MAAm)) Swelling Properties