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The Diagenesis of Plant Lipids during the Formation of the Krepoljin Coal Basin(Serbia)—Using Multivariate Statistical Analysis in the Saturated Biomarkers

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Acta Geologica Sinica(English Edition) 2008年第6期82卷 1168-1178页

作者： Gordana devi Branimir JOVANIEVI Center of Chemistry IChTMNjegoeva 1211000 BelgradeSerbia Faculty of Chemistry University of BelgradePOB 15811001 BelgradeSerbia

The composition of the saturated hydrocarbon fraction of soluble organic matter （bitumen） from the Krepoljin brown coal basin （East Serbia） of Miocene age was investigated. The Krepoljin basin is especially interesting from a geochemical point of view. Namely, by the end of Tertiary Period, the basin was covered by powerful Mesozoic formations of great possibilities, the bedding became hermetically enclosed and protected from subsequent external influences. The nature of early diagenetic processes in the environment with abundant accumulation of organic substance is defined by the molecular content of bitumen through the connections of molecular structures to potential precursors in paleoplant phylla, as well as by the degree of their diagenetic transformations. The hierarchy of parameters based on molecules of saturated hydrocarbons was determined by applying the principal component analysis to the soluble organic matter. The most significant, most ＂loadings＂ values of component CI, are the plant types such as precursors or participants in early diagenetic transformations of steranes Cs27-algal precursor material, Cs28-moulds, Cs29-higher land and water plants; resinous from the group of higher plant gymnosperms （G）; also triterpanes a and β-amirindicotyledonous angiosperms （A） and bacterial and/or terrestrial plants population represented by hopanes/moretanes; as well as the parameters which describe the degree of diagenetic/maturation transformation of precursor biomass, and based on next reactions：（1） shifting of methyl group, influenced by the inorganic sediment constitutents, sterane-rearranged steranes, （2） isomerization in the ring system, ααα→βββ C29 sterane as well as （3） isomerization on chiral center of the side chain sequence R→S C29 sterane S/（S＋R）. Additionally, a pyrite-derived inhibitory effect on the rearrangment of C29 steranes must be taken into account, but not on triterpanes reaction. Non- appearance of statistically important correlations, be

关键词： brown coal diagenetic transformations of saturated biomarkers diagenetic transformations of saturated biomarkers steranes diterpanes and triterpanes principal component

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Visual Enhancement of Underwater Images Using Transmission Estimation and Multi-Scale Fusion

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Computer Systems Science & Engineering 2023年第3期44卷 1897-1910页

作者： R.Vijay Anandh S.Rukmani devi Department of Electronics and Communication Engineering RMK College of Engineering and TechnologyTiruvallurTamilnadu601206India Department of Electronics and Communication Engineering RMD Engineering CollegeGummidipundiTamilnadu601206India

The demand for the exploration of ocean resources is increasing *** image data plays a significant role in many research *** this,the visual quality of underwater images is degraded because of two main factors namely,backscattering and ***,visual enhancement has become an essential process to recover the required data from the *** algorithms had been proposed in a decade for improving the quality of *** paper aims to propose a single image enhancement technique without the use of any external *** that,the degraded images are subjected to two main processes namely,color correction and image ***,veiling light and transmission light is estimated tofind the color required for *** light refers to unwanted light,whereas transmission light refers to the required light for color *** estimated outputs are applied in the scene recovery *** image obtained from color correction is subjected to a fusion process where the image is categorized into two versions and applied to white balance and contrast enhancement *** resultants are divided into three weight maps namely,luminance,saliency,chromaticity and fused using the Laplacian *** results obtained are graphically compared with their input data using RGB Histogram ***,image quality is measured and tabulated using underwater image quality measures.

关键词： Underwater image backscattering attenuation image fusion veiling light white balance laplacian pyramid

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Molecular dynamics approach on intermolecular interaction between n-icosane and gemini surfactant assisted nanoparticles

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Petroleum Research 2022年第3期7卷 366-371页

作者： Shamala devi Vijayakumar Junaidi Zakaria Norida Ridzuan Author's Faculty of Chemical and Process Engineering Technology Universitiy Malaysia Pahang26300GambangPahangMalaysia

Wax molecules tend to aggregate,and form wax solid at low temperature and result in a wax *** wax inhibitors are introduced to prevent wax ***,the performance of chemical wax inhibitors is temperature *** method using Molecular Dynamics(MD)simulation is used in this research to investigate how temperature affects wax inhibition using 2,5,8,11 Tetramethyl 6 dodecyn-5,8 Diol Ethoxylate Gemini surfactant(GS)and nanoparticles silicon dioxide(NP1),tin oxide(NP2),and nickel oxide(NP3).Wax-wax interaction of H58⋯H61of n-icosane and wax-solute interaction of hydrogen atom from n-icosane wax and carbonyl oxygen atoms from GS and NPs was investigated via radial distribution function analysis(rdf).The findings revealed that GS/NPs blends have a better chance of wax inhibition than corresponding *** that,wax-wax interaction was strongest at 288K,indicating the higher chances of wax formation at low *** simulation is a promising tool for identifying atoms responsible for the wax formation and inhibition and can be used for chemical wax inhibitor screening for different temperature.

关键词： Gemini surfactant Nanoparticles rdf analysis Intermolecular interaction Temperature

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Fabrication of Large Area High Density, Ultra-Low Reflection Silicon Nanowire Arrays for Efficient Solar Cell Applications

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Nano Research 2011年第11期4卷 1136-1143页

作者： Subramani Thiyagu B. Parvathy devi Zingway Pei Graduate Institute of Optoelectronic Engineeringi Department of Electdcal Engineeringi Chung Hsing University Taichung 40227Taiwan China

High density vertically aligned and high aspect ratio silicon nanowire （SiNW） arrays have been fabricated on a Si substrate using a template and a catalytic etching process. The template was formed from polystyrene （PS） nanospheres with diameter 30-50 nm and density 10^10/cm^2, produced by nanophase separation of PS-containing block-copolymers. The length of the SiNWs was controlled by varying the etching time with an etching rate of 12.5 nm/s. The SiNWs have a biomimetic structure with a high aspect ratio （-100）, high density, and exhibit ultra-low reflectance. An ultra-low reflectance of approximately 0.1% was achieved for SiNWs longer than 750 nm. Well-aligned SiNW/poly（3,4-ethylenedioxy-thiophene）：poly（styrenesulfonate）（PEDOT：PSS） heterojunction solar cells were fabricated. The n-type silicon nanowire surfaces adhered to PEDOT：PSS to form a core-sheath heterojunction structure through a simple and efficient solution process. The large surface area of the SiNWs ensured efficient collection of photogenerated carriers. Compared to planar cells without the nanowire structure, the SiNW/PEDOT：PSS heterojunction solar cell exhibited an increase in short-circuit current density from 2.35 mA/cm^2 to 21.1 mA/cm^2 and improvement in power conversion efficiency from 0.4% to 5.7%.

关键词： Ultra-low reflection silicon nanowire polystyrene nanosphere heterojunction solar cell

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Loss of Exchange Symmetry in Multiqubit States under Ising Chain Evolution

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Chinese Physics Letters 2011年第2期28卷 39-42页

作者： Sudha B.G.Divyamani A.R.Usha devi Department of Physics Kuvempu UniversityShankaraghattaShimoga-577451India DAMTP Centre for Mathematical SciencesWilberforce RoadCambridgeCB3OWAUK Department of Physics Bangalore UniversityBangalore-560056India Inspire Institute Inc. McLeanVA 22101USA.

Keeping in view of importance of exchange symmetry aspects in studies on spin squeezing of multiqubit states,we show that the one-dimensional Ising Hamiltonian with nearest neighbor interactions does not retain the exchange symmetry of initially symmetric multiqubit *** we show that among 4-qubit states obeying exchange symmetry,all states except W class(and their linear combination)lose their symmetry under time evolution with Ising *** the loss of symmetry of the initially symmetric states to rotational asymmetry of the one-dimensional Ising Hamiltonian with more than 3 qubits,we indicate that all N-qubit states(N>5)obeying permutation symmetry lose their symmetry after time evolution with Ising Hamiltonian.

关键词： symmetry Ising qubit

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Synthesis of Pr-doped ZnO nanoparticles: Their structural,optical, and photocatalytic properties

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Chinese Physics B 2018年第8期27卷 393-399页

作者： Jun-Lian Chen Neena devi Na Li De-Jun Fu Xian-Wen Ke School of Printing and Packaging Wuhan UniversityWuhan 430072 China Hubei Key Laboratory of Nuclear Solid Physics and School of Physics and Technology Wuhan UniversityWuhan 430072China

Undoped and praseodymium-doped zinc oxide （Pr-doped ZnO）（with 2.0-mol%-6.0-mol% Pr） nanoparticles as sunlight-driven photocatalysts are synthesized by means of co-precipitation with nitrates followed by thermal annealing. The structure, morphology, and chemical bonding of the photocatalysts are studied by x-ray diffraction （XRD）, scanning electron microscopy （SEM） with energy dispersive x-ray emission spectroscopy （EDS）, x-ray photoelectron spectroscopy （XPS）, and Fourier transform infrared spectroscopy （FTIR）, respectively. The optical properties are studied by photolu- minescence （PL） and UV-vis diffuse reflectance spectroscopy （UV-vis DRS）. We find that Pr doping does not change the crystallinity of ZnO; but it reduces the bandgap slightly, and restrains the recombination of the photogenerated electron-hole pairs. The photocatalytic performance of the photocatalysts is investigated by the photodegradation reaction of 10-mg/L rhodamine B （RhB） solution under simulated sunlight irradiation, showing a degradation rate of 93.75% in ZnO doped with 6.0-mo1% Pr.

关键词： ZnO, Pr-doped photocatalytic activity

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Solvent extraction and separation of copper from base metals using bifunctional ionic liquid from sulfate medium

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Transactions of Nonferrous Metals Society of China 2016年第3期26卷 874-881页

作者： Niharbala devi Department of Chemistry Institute of Technical Education and ResearchSiksha 'O’Anusandhan Deemed UniversityKhandagiri SquareOR 751030India

A novel solvent extraction process for extraction and separation of copper from other base metal ions using a bifunctional ionic liquid (IL) (trioctylmethylammonium/2,4,4-trimethylpentyl phosphinate, [A336/Cy272]) in kerosene was reported. This IL was found to extract copper more efficiently than the individual extractants Aliquat 336 or Cyanex 272. Formation of an octahedral copper-IL complex was characterized by UV-Visible spectra and metal ligand interaction was confirmed by FTIR spectra. The loading capacity of 0.1 mol/L [A336/Cy272] was found to be 1.71 g/L. Stripping studies reported that 0.298 g/L copper ions were efficiently stripped using 0.1 mol/L sulfuric acid from 0.05 mol/L loaded IL. The selectivity of copper against nickel, cadmium and iron was investigated from their equimolar binary mixtures using 0.05 mol/L [A336/Cy272] in kerosene. The highest separation factorβCu/Cd=8.41 was obtained at pH 3.56. Copper can be effectively separated from nickel over the pH range studied. The IL extracts preferentially iron over copper and the highest separation factorβFe/Cuwas 3246 at pH 2.4. The extraction rate of metal ions from a synthetic solution containing copper with other metal impurities was in the order of Fe>Zn>Cu>Cd>Co>Ni.

关键词： copper ionic liquid extraction stripping separation

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A Novel Outlier Detection with Feature Selection Enabled Streaming Data Classification

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Intelligent Automation & Soft Computing 2023年第2期35卷 2101-2116页

作者： R.Rajakumar S.Sathiya devi Anna University Chennai600025India University College of Engineering BIT CampusAnna UniversityTiruchirappalli620024India

Due to the advancements in information technologies,massive quantity of data is being produced by social media,smartphones,and sensor *** investigation of data stream by the use of machine learning(ML)approaches to address regression,prediction,and classiﬁcation problems have received consid-erable *** the same time,the detection of anomalies or outliers and feature selection(FS)processes becomes *** study develops an outlier detec-tion with feature selection technique for streaming data classiﬁcation,named ODFST-SDC ***,streaming data is pre-processed in two ways namely categorical encoding and null value *** addition,Local Correla-tion Integral(LOCI)is used which is signiﬁcant in the detection and removal of ***,red deer algorithm(RDA)based FS approach is employed to derive an optimal subset of ***,kernel extreme learning machine(KELM)classiﬁer is used for streaming data classiﬁ*** design of LOCI based outlier detection and RDA based FS shows the novelty of the *** order to assess the classiﬁcation outcomes of the ODFST-SDC technique,a series of simulations were performed using three benchmark *** experimental results reported the promising outcomes of the ODFST-SDC technique over the recent approaches.

关键词： Streaming data classiﬁcation outlier removal feature selection machine learning metaheuristics

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Enhancement of IoT device security using an Improved Elliptic Curve Cryptography algorithm and malware detection utilizing deep LSTM

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高置信计算(英文) 2023年第2期3卷 18-31页

作者： R.Aiyshwariya devi A.R.Arunachalam Department of Computer Science and Engineering Dr.M.G.R.Educational and Research InstituteChennai 600095India

Internet of things(IoT)has become more popular due to the development and potential of smart technology *** concerns against IoT infrastructure,applications,and devices have grown along with the need for IoT *** system security protocols are difficult due to the diverse capabilities of IoT devices and the dynamic,ever-changing environment,and simply applying basic security requirements is ***,this proposed work designs a malware detection and prevention approach for secure data transmission among IoT *** malware detection approach is designed with the aid of a deep learning *** initial process is identifying attack nodes from normal nodes through a trust value using contextual *** discovering attack nodes,these are considered for predicting different kinds of attacks present in the network,while some preprocessing and feature extraction strategies are applied for effective *** Deep LSTM classifier is applied for this malware detection *** completed malware detection,prevention is performed with the help of the Improved Elliptic Curve Cryptography(IECC)algorithm.A hybrid MA-BW optimization is adopted for selecting the optimal key during *** 3.8 software is used to test the performance of the proposed approach,and several existing techniques are considered to evaluate its *** proposed approach obtained 95%of accuracy,5%of error value and 92%of *** addition,the improved ECC algorithm is also compared with some existing algorithm which takes 6.02 s of execution *** to the other methods,the proposed approach provides better security to IoT gadgets during data transmission.

关键词： Deep LSTM Improved Elliptic Curve Cryptography Malware detection Prediction of different kinds of attacks IoT gadgets

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Detection and Classification of Diabetic Retinopathy Using DCNN and BSN Models

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Computers, Materials & Continua 2022年第7期72卷 597-609页

作者： S.Sudha A.Srinivasan T.Gayathri devi Department of ECE SRCSASTRA Deemed UniversityKumbakonamIndia

Diabetes is associated with many complications that could lead to *** retinopathy,a complication of diabetes,is difficult to diagnose and may lead to vision *** identification of micro features in fundus images for the diagnosis of DR is a complex and challenging task for *** clinical testing involves complex procedures and is timeconsuming,an automated system would help ophthalmologists to detect DR and administer treatment in a timelymanner so that blindness can be *** research works have focused on image processing algorithms,or neural networks,or signal processing techniques alone to detect diabetic ***,we aimed to develop a novel integrated approach to increase the accuracy of *** approach utilized both convolutional neural networks and signal processing *** this proposed method,the biological electro retinogram(ERG)sensor network(BSN)and deep convolution neural network(DCNN)were developed to detect and classify *** the BSN system,electrodes were used to record ERGsignal,which was preprocessed to be *** was performed in the frequency domain by the application of fast Fourier transform(FFT)and mel frequency cepstral coefficients(MFCCs)were *** neural network(ANN)classifier was used to classify the signals of eyes with DR and normal ***,fundus images were captured using a fundus camera,and these were used as the input for DCNN-based *** DCNN consisted of many layers to facilitate the extraction of features and classification of fundus images into normal images,non-proliferative DR(NPDR)or earlystage DR images,and proliferative DR(PDR)or advanced-stage DR ***,it classifiedNPDRaccording tomicroaneurysms,hemorrhages,cotton wool spots,and exudates,and the presence of new blood vessels indicated *** accuracy,sensitivity,and specificity of the ANNclassifier were found to be 94%,95%,and 93%,***

关键词： Deep convolution neural network artificial neural network nonproliferative diabetic retinopathy biological ERG sensor network

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