j) 2016 - 39 Documents

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ACENAPHTHO[1,2-B]QUINOXALINE AND ACENAPHTHO[1,2-B]PYRAZINE AS CORROSION INHIBITORS FOR MILD STEEL IN ACID MEDIUM
(Elsevier, 2016-01) Saranya, J; Sounthari, P; Parameswari, K; Chitra, S
The corrosion inhibition of mild steel in 1 M H2SO4 using acenaphtho[1,2-b]quinoxaline and acenaphtho[1,2-b]pyrazine at 303–333 K have been investigated. The study was performed using weight loss method, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). Polarization measurements proved that the inhibitors behave as mixed-type. EIS data showed that the charge transfer resistance of mild steel increases in acid solution containing inhibitors. The surface morphology was evaluated using scanning electron microscope (SEM), atomic force microscopy (AFM) techniques. Density functional theory (DFT) at the B3LYP/6-311G(d,p) basis set level was performed. Excellent correlation was found between experimental and theoretical results.
ASSESSMENT OF COMPETENCE OF THE PSEUDOMONAS AERUGINOSA TO SOLUBILIZE INSOLUBLE FORM OF ZINC UNDER VARIOUS CULTURAL PARAMETERS
(Springer Link, 2016) Padma Devi, S N; Sunitha kumari, K; Vasandha, S
Efficiency of Pseudomonas aeruginosa to solubilize insoluble form of zinc to soluble form was studied under various cultural parameters such as carbon (glucose, fructose, sucrose, maltose and lactose), nitrogen (ammonium sulphate, sodium nitrate, potassium nitrate and urea), pH (5.0, 7.0 and 9.0) and temperature (20, 30 and 40°C). The experimental study was carried out by both qualitative (plate assay) and quantitative (broth assay) methods. The Zn-solubilizing efficiency of the isolate was found more when glucose was added as C-source in both plate (150 %) and broth (16.62 mg/l) assays, and the efficiency was less in the medium amended with sucrose as carbon source in both qualitative (105.8 %) and quantitative (2.56 mg/l) estimation. Among the four nitrogen sources, P. aeruginosa showed best solubilizing efficiency (262.5 %) and solubilization of Zn (29.91 mg/l) in the presence of ammonium sulphate and recorded least solubilization efficiency in the presence of sodium nitrate as nitrogen source in both plate (181.82 %) and broth (21.92 mg/l) assays. It showed highest solubilization of zinc from ZnO at the incubation temperature of 30°C, and the activity was less at the temperature of 40°C. pH 7 was the most favourable pH for solubilization, and the efficacy was least when the pH reached its alkalinity. Thus the study confirmed the efficiency of P. aeruginosa to solubilize insoluble form of zinc and can be used as a source of bioinoculants to eradicate zinc deficiency in plants.
ASSESSMENT OF PHYSICOCHEMICAL CHARACTERISTICS AND THE LEVEL OF NUTRIENT CONTENTS AS WELL AS HEAVY METAL IONS IN WATERS OF THREE LAKES AT COIMBATORE, TAMIL NADU, INDIA
(Journal of Materials and Environmental Science, 2016-02-26) Manikandan, R; Ezhili, N; Muthulakshmiandal, N; Paulo J. C, Favas; Venkatachalam, P
Lake water quality degradation and heavy metals pollution have been serious environmental threats for last decades, especially in those fresh water lakes situated in the vicinity of the cities and human habitations. The present study aimed to investigate the physicochemical parameters, level of nutrient contents and heavy metals to determine the water quality of Ukkadam, Kuruchi and Singanallur Lakes. All the physicochemical parameters except dissolved oxygen, sulphate, silicate and nitrate values were found above the prescribed limit as recommended by WHO (2011) and BIS (2003) drinking water quality. The concentrations of Ca, Cr, Cu, Fe, Niand Pb in waters of the selected three lakes ranged from 0.014 – 0.038, 0.145 – 0.063, 0.025 – 0.552, 0.100 – 3.460, 0.028 – 0.117 and 0.463 – 2.172 mg/L respectively. The concentrations of heavy metals except Cu were found to be higher than the permeable dose. This investigation revealed that the water in these lakes is partially contaminated with high level of heavy metals. It is recommended that proper implementation of new wetland waste management system and constant monitoring is urgently required to maintain good water quality in these lakes for future generation.
BIOSORPTION OF DIVALENT ION ONTO TREATED PROSOPIS JULIFLORA BARK FROM AQUEOUS SOLUTIONS - ISOTHERMAL AND STATISTICAL ANALYSIS
(Oriental Journal of Chemistry, 2016-04-13) Muthulakshmi Andal, N; Charulatha, S; Gayathri, N S
The present work emphasizes the utilization of Prosopis juliflora bark, an agro waste material for the adsorption of Cu(II). The raw Prosopis juliflora bark (PJB) is treated using 0.1N hydrochloric acid to enhance the sorption efficiency. The characterization studies of TPJB using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analysis (EDAX), Brunauer-Emmet-Teller(BET) and Barrett-Joyner-Halenda (BJH) analyses carried out. The batch mode experimental set up is verified to assess the sorption capacity of the chosen material for the operating factors viz., particle sizes/ doses of the sorbent material upon a range of initial concentrations of Cu(II) at different temperatures, agitation time and pH of the Cu(II)- TPJB system. The amount of Cu(II) ion adsorbed on to TPJB surface is found to be 43.11 mg/g (97.4%) under optimized conditions, its efficiency 3 fold times more than the Ce values reported by other researchers. The sorption characteristic of TPJB is quantitatively estimated through column experiments based on the C value by batch mode. The removal is observed as 98%. Langmuir, Freundlich and Tempkin isothermal curves at various initial concentrations are plotted for Cu(II)-TPJB system wherein the straight line fit is best suited for the Freundlich isotherm model. The results show that the response of TPJB in trapping Cu(II) ions are influenced by various parameters being statistically verified using SPSS software, indicative of good correlation.
BIOSYNTHESIS OF PVA ENCAPSULATED SILVER NANOPARTICLES
(Una Publication, 2016-10-01) Sharmila, Chandran; Vinuppriya, Ravichandran; Selvi, Chandran; Jincy, Chemmanda; Bellan, Chandarshekar
Green synthesis of metal nanoparticles is an important technique in the methods of eco-friendly nanoparticle production. The synthesis of silver nanoparticles was accomplished using Ocimum sanctum leaf extract at room temperature. These particles were then encapsulated with polyvinyl alcohol (PVA) polymer matrix. The presence of silver was confirmed by different characterization techniques such as UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR) and X-Ray Diffraction (XRD). Scanning electron microscopic (SEM) images of the synthesized powder shows spherical shaped silver nanoparticles embedded in sponge-like polymer matrix. The energy dispersive X-ray analysis confirms the presence of elemental silver along with iron signal. Energy dispersive signal corresponding to elemental iron has been attributed to O. sanctum plant. The silver nanoparticles in PVA matrix thus obtained shows high antibacterial activity against gram positive Staphylococcus aureus (S. aureus) and gram negative Escherichia coli (E. coli) water borne bacteria. The inhibition zone against S. aureus and E. coli were also calculated.
CANCELLABLE MULTIMODAL BIOMETRIC USER AUTHENTICATION SYSTEM WITH FUZZY VAULT
(IEEE, 2016-05-30) Soruba Sree, S R; Radha, N
Biometrics refers to authentication techniques that rely on humans physical and behavioral characteristics that can be automatically checked. Biometric based authentication system provides robust security and ease of use than conventional methods of verification system. Multimodal biometric system is one of the major areas of study identified with large applications in recognition system. Unimodal biometric systems challenge with a wide variety of problems such as noisy data, Intra-class variations, non-universality, and spoof attacks. Some of these limitations can be solved in multimodal biometric system. In proposed work, face and fingerprint biometric traits are used for multimodal biometric authentication system. Biometric traits are transformed using distortion algorithm. After the transformation processes pre-processing of images are done to improve the clear visibility of images. The extractions of minutiae features from fingerprint are achieved using Crossing Number concept and the face features are extracted using the Local Binary Pattern algorithm. To combine both the face and fingerprint features feature level fusion is used. In order to provide additional security to the proposed work the fuzzy vault is introduced by adding duplicate values and having a secret key to lock and unlock the system. Fuzzy vault and distortion acts as an additional layer of security in multimodal biometric user authentication system.
CLASSIFICATION OF HEART RATE DATA USING BFO-KFCM CLUSTERING AND IMPROVED EXTREME LEARNING MACHINE CLASSIFIER
(IEEE, 2016-05-30) Kavitha, R; Christopher, T
The Electrocardiogram is a tool used to access the electrical recording and muscular function of the heart and in last few decades it is extensively used in the investigation and diagnosis of heart related diseases. It must be noted that the heart rate fluctuates not only because of cardiac demand, however is also influenced as a result of the occurrence of cardiac disease and diabetes. In addition, it has been shown that Heart Rate Variability (HRV) may well be utilized as an early indicator of cardiac disease susceptibility and the existence of diabetes. As a result, the HRV can be exercised for early clinical test of these diseases. Most existing systems make use of Support Vector Machine (SVM), owing to the generalization performance, it is not sufficient for the accurate classification of heart rate data. In order to overcome this complication, Improved Extreme Learning Machine (IELM) classifier is used, to obtain the best parameter value and best feature subset through the use of Bacterial Foraging Optimization (BFO) that feed the classifier. Here in this work, features of linear and nonlinear are extracted from the HRV signals. Following the preprocessing, feature extraction is done effectively together with feature selection with the assistance of BFO for the purpose of data reduction. Subsequently, proposed a scheme to integrate Kernel Fuzzy C-Means (KFCM) clustering and classifier to adequately enhance the accuracy result for ECG beat classification. The accuracy result for classification of heart rate data is shown in the proposed scheme.
CO(II) COMPLEX OF 2-AMINO-6-METHYLBENZOTHIAZOLE: SYNTHESIS, STRUCTURE AND BIOLOGICAL EVALUATION
(Indian Journal of Chemistry, 2016-11) Jone Kirubavathy, S; Velmurugan, R; Karvembu, R; Bhuvanesh, N S P; Enoch, I V M V; Mosae Selvakumar, P; Chitra, S
Cobalt(II) complex of 2-amino-6-methylbenzothiazole has been synthesized and characterized by various physicochemical methods. The ligand 2-amino-6-methylbenzothiazole acts as monodentate, neutral ligand with N as the donor site. The molecular structure of the title complex has been determined by single crystal X-ray diffraction studies. The Co(II) complex shows significant antioxidant activity against DPPH radical. The complex shows cytotoxicity with a IC50 value of 14.12 µM against MCF-7 cell line. In addition, the complex shows good antimicrobial and anti-tuberculosis activities against various microbes and mycobacterium tuberculosis respectively. DNA binding of the title complex has been investigated by absorption spectroscopic technique, which reveals that the complex acts as minor groove binder. These results have been validated by molecular docking studies
COMMUNITY DETECTION BASED ON GIRVAN NEWMAN ALGORITHM AND LINK ANALYSIS OF SOCIAL MEDIA
(Springer Link, 2016-11-23) Sathiyakumari, K; Vijaya, M S
Social networks have acquired much attention recently, largely due to the success of online social networking sites and media sharing sites. In such networks, rigorous and complex interactions occur among numerous one-of-a-kind entities, main to massive statistics networks with notable enterprise capacity. Community detection is an unsupervised learning task that determines the community groups based on common interests, occupation, modules and their hierarchical organization, using the information encoded in the graph topology. Finding communities from the social network is a difficult task because of its topology and overlapping of different communities. In this research, the Girvan-Newman algorithm based on Edge-Betweenness Modularity and Link Analysis (EBMLA) is used for detecting communities in networks with node attributes. The twitter data of the well-known cricket player is used right here and community of friends and fans is analyzed based on three exclusive centrality measures together with a degree, betweenness, and closeness centrality. Also, the strength of extracted communities is evaluated based on modularity score using proposed method and the experiment results confirmed that the cricket player’s network is dense.
CORROSION ABATEMENT IN ACID PICKLING INDUSTRIES BY EFFECTIVE N-HETEROCYCLIC COMPOUNDS: DRY AND WET LAB STUDIES
(NACE - International Corrosion Conference Series, 2016-03-06) Sowmya, Ramkumar; Nalini, D
During the chemical cleaning process using acids, in many electroplating and other descaling industries, there exists the problem of heavy metal loss. Hence there is always a need for abatement of this metal loss. A critical (steady state) value of the resistivity to corrosion of two organic compounds, 5-[2-(4-methoxyphenyl)-vinyl]-3-phenyl isoxazole (MVI) and 5-[2-(4-methoxyphenyl)-vinyl]-1,3,8-triazacyclopenta[ a]indene (MCI) were determined by a combination of non-electrochemical and electrochemical monitoring techniques. The behavior of organic compound, on a metallic alloy, i.e., mild steel, was investigated over a temperature range of 30 to 70°C. Efficiency of MVI and MCI were determined by correlating the electrochemical response of the compound (by electrochemical impedance and potentiodynamic polarization) in 1M HCl and 0.5M H2SO4 solution with their structural features. EIS measurement predicted the physical adsorption of both MVI and MCI on the metal surface from PZC calculation. Polarization studies proved that the inhibitors retard both the electrode process during inhibition. The integrity of the inhibitors efficiency with respect to time was assessed from mass loss measurements at different immersion period. Mass loss measurements proved that both MVI and MCI inhibit corrosion of mild steel in 1M HCl with a maximum efficiency of 91.07% and 78.23% at 20 ppm in HCl and H2SO4 respectively for MVI, 97.72% and 88.64% at 20 ppm in HCl and H2SO4 respectively for MCI. Hence MVI and MCI were found to be effective inhibitors for acid cleaning process in industries. The mechanism of the inhibition process was discussed in the light of the chemical structure and quantum chemical calculations of the investigated inhibitor. MVI and MCI were modeled in order to assess its absorbability using density functional theory (DFT) and revealed remarkably high interaction energies, which corroborate the experimental findings.
CORROSION INHIBITION OF N80 STEEL IN 15% HCL BY PYRAZOLONE DERIVATIVES: ELECTROCHEMICAL, SURFACE AND QUANTUM CHEMICAL STUDIES
(Royal Society of Chemistry, 2016-02-23) Ansari, K R; Quraishi, M A; Ambrish, Singh; Sowmya, Ramkumar; Ime B, Obote
The corrosion protection of N80 steel in 15% HCl by two pyrazolone derivatives namely 2-(3-amino-5-oxo-4,5-dihydro-1H-pyrazol-1-yl)(p-tolyl)methyl)malononitrile (PZ-1) and 2-((3-amino-5-oxo-4,5-dihydro-1H-pyrazol-1-yl)(phenyl)methyl)malononitrile (PZ-2) has been investigated by using gravimetric, electrochemical and quantum chemical studies. The observed results reveal that PZ-1 is a better inhibitor than PZ-2. Tafel polarization showed that PZs are mixed type inhibitors but dominantly affect the cathodic reaction. Both inhibitors were found to obey the Langmuir adsorption isotherm. Scanning electron microscopy (SEM) and scanning electrochemical microscopy (SECM) images support the protection of the N80 steel in the presence of the PZs. Quantum chemical study reveals that both inhibitors have a tendency to get protonated and this result supports the experimental observations.
CORROSION INHIBITION PROPERTY OF POLYESTER–GROUNDNUT SHELL BIODEGRADABLE COMPOSITE
(Elsevier, 2016-12) Sounthari, P; Kiruthika, A; Saranya, J; Parameswari, K; Chitra, S
The use of natural fibers as reinforcing materials in thermoplastics and thermoset matrix composites provide optimistic environmental profits with regard to ultimate disposability and better use of raw materials. The present work is focused on the corrosion inhibition property of a polymer matrix composite produced by the use of groundnut shell (GNS) waste. Polyester (PE) was synthesized by condensation polymerization of symmetrical 1,3,4-oxadiazole and pimelic acid using sodium lauryl sulfate as surfactant. The polyester–groundnut shell composite (PEGNS) was prepared by ultrasonication method. The synthesized polyester–groundnut shell composite was characterized by FT-IR, TGA and XRD analysis. The corrosion inhibitory effect of PEGNS on mild steel in 1 M H2SO4 was investigated using gravimetric method, electrochemical impedance spectroscopy, potentiodynamic polarization, atomic absorption spectroscopy and scanning electron microscopy. The results showed that PEGNS inhibited mild steel corrosion in acid solution and indicated that the inhibition efficiency increased with increasing inhibitor concentration and decrease with increasing temperature. The composite inhibited the corrosion of mild steel through adsorption following the Langmuir adsorption isotherm. Changes in the impedance parameters Rt, Cdl, Icorr, Ecorr, ba and bc suggested the adsorption of PEGNS onto the mild steel surface, leading to the formation of protective film.
DRY AND WET LAB ANALYSIS ON BENZOFUSED HETEROCYCLIC COMPOUNDS AS EFFECTIVE CORROSION INHIBITORS FOR MILD STEEL IN ACIDIC MEDIUM
(Elsevier, 2016-08-25) Venkatesan, Hemapriya; Mayakrishnan, Prabakaran; Kandasamy, Parameswari; Subramaniyan, Chitra; Seung-Hyun, Kim; Ill-Min, Chung
The influence of two benzofused heterocyclic compounds, namely 2-phenylquinazolin-4(3H)-one(PQO) and 2-phenyl-4H-benzo[d]oxazin-4-one(POO) in controlling mild steel corrosion in 1 M H2SO4 solution was investigated using gravimetric and electrochemical methods. The experimental results revealed that both the inhibitors inhibit corrosion and their inhibition efficiency follows the order PQO > POO. A mixed mode of inhibition from polarization and a charge transfer mechanism from impedance study in the absence and presence of inhibitors were found. The passive film formed on the mild steel surface was characterized using SEM-EDX. Quantum chemical parameters derived using DFT performed at B3LYP/6-31G(d, p) level were used to correlate the molecular structure.
EFFECT OF PARTICLE SIZE ON OPTICAL AND ELECTRICAL PROPERTIES IN MIXED CDS AND NIS NANOPARTICLES SYNTHESIS BY ULTRASONIC WAVE IRRADIATION METHOD
(Elsevier, 2016-12) Mohanraj, V; Jayaprakash, R; Robert, R; Balavijayalakshmi, J; Gopi, S
The mixed phase CdS and NiS nanoparticles are prepared by adopting ultrasonic wave irradiation method under different doping concentration of Ni in CdS. The well defined nano spheres are obtained during this synthesis process. The predicted particle sizes from X-ray diffraction (XRD) analysis are found to lie in the range between 37 and 49 nm. The effective doping of Ni lead to form the mixture of two phases such as CdS and NiS. The respective change due to the formation of mixture of CdS and NiS is reflected well in the band gap energy which is measured in Diffused Reflectance Spectra (DRS). It is predicted in the range of 2.41–2.23 eV respectively. Consistency of particle size with XRD are confirmed from Transmission Electron Microscope (TEM) images and also identified the presence of Nickel Sulfide and Cadmium Sulfide in nanostate with average particle size as 54 nm. The Energy Dispersive X-ray (EDAX) analysis confirmed the existence of Ni, Cd and S the doping levels. The optical absorption analysis of samples are performed in UV–vis range 400–600 nm. The synthesized samples are further characterized Fourier Transform Infrared (FT-IR) spectroscopy, Thermogravimetric (TGA) analysis, I-V characteristic and conductivity measurements.
EFFICACY OF PLEUROTUS SAJOR CAJU AS AN EXCELLENT POTTING MEDIUM FORGARDEN PLANTS
(International Journal of Pharma and Bio Sciences, 2016) Harathi, P; Radha, R; Gayathri, M
Coir is a natural fibre found between the hard, internal shell and the outer coat of a coconut is used as a by-product of the coir manufacturing industry. Normally, they are dumped as agricultural wastes in the fields or disposed by burning which causes air pollution. Composting of coir pith is an alternate method to reduce pollution and it also serves as a source for the maintenance of organic matter of the soil. Coir pith is an ideal soil re-conditioner and soil substrate with excellent water holding capacity. Coir pith contains high quality of nutrients which keeps the soil healthy in a natural way. It acts as a top dressing that helps to maintain moisture content of the soil and re-conditions the soil. The proportion yielded effective growth of the plant and indicating its use as an excellent potting media for garden plants. Hence the objective of the present study focused on the efficacy of basidiomycetes fungus, Pleurotus sajor-caju for the cultivation of medicinal plant, Ocimum santum using the biodegraded coir pith
EFFICIENCY OF ASPERGILLUS TERREUS TO SOLUBILIZE INSOLUBLE FORM OF PHOSPHORUS INTO SOLUBLE FORM UNDER VARIOUS CULTURAL CONDITIONS
(International Journal of Pharma and Bio Sciences, 2016-03) Anitha, S; Padma Devi, S N
Phosphorous forms the second major nutrient required by the plants for its growth. It is supplied to the plants in the form of synthetic fertilizer which gets accumulated in the soil due its conversion into unavailable form. Transformation of unavailable form of phosphorus (P) to an available form becomes inevitable due to its physiological and biochemical role in plants. Since its deficiency results in the cessation of plant growth, supplementation of soluble form of phosphorus becomes essential. Fungus has the capability to convert insoluble form of phosphorus to soluble form through the secretion of organic acid as one of the solubilization mechanism. Thus in the present study, Aspergillus terreus was isolated from the rhizospheric soil sample of tomato field and was tested for its phosphorus solubilization efficacy by Broth assay method. The strain showed highest solubilization (7.5 mg/l) at the 10th day of incubation with the pH drop of 4.0. Solubilization efficacy of the isolate was high due to the secretion of organic acid (gluconic acid) which was confirmed by HPLC method. Effect of various parameters such as Carbon sources, Nitrogen sources, pH and Temperature on the solubilization of phosphorus by A. terreus was also tested. The strain showed maximum solubilization in the presence of fructose as carbon source, ammonium sulphate as a nitrogen source, at the temperature of 30ËšC and at the pH of 7.0 in both qualitative and quantitative assays. Thus A. terreus shall be used as a viable Bioinoculant to eradicate P- deficiency in plants.
EVALUATION OF POLYPHENOL COMPOSITION AND ANTI-CORROSION PROPERTIES OF CRYPTOSTEGIA GRANDIFLORA PLANT EXTRACT ON MILD STEEL IN ACIDIC MEDIUM
(Elsevier, 2016-05-25) Mayakrishnan, Prabakaran; Seung-Hyun, Kim; Venkatesan, Hemapriya; Ill-Min, Chung
The total phenolic and flavonoid compounds present in Cryptostegia grandiflora leaf extract were analyzed. The results confirmed that the extract contains the Myricetin 3582.22(μg/g) and Rutin 45.62(μg/g) as major components. C. grandiflora extract was evaluated for its anti-corrosion property on mild steel in 1 M H2SO4. A maximum inhibition efficiency of 87.54% was achieved by using 500 ppm of the inhibitor. Polarization studies indicate that the extract acts as a mixed inhibitor. The formation of productive layer on mild steel by inhibitor was confirmed by SEM-EDS and AFM. The extract is adsorbed on the mild steel according to Temkin adsorption isotherm.
EXISTENCE AND EXPONENTIAL STABILITY FOR NEUTRAL STOCHASTIC INTEGRODIFFERENTIAL EQUATIONS WITH IMPULSES DRIVEN BY A FRACTIONAL BROWNIAN MOTION
(Elsevier, 2016-03) Arthi, G; Ju H, Park; H Y, Jung
In this paper, we establish the results on existence and uniqueness of mild solution of impulsive neutral stochastic integrodifferential equations driven by a fractional Brownian motion. Further, by using an impulsive integral inequality, some novel sufficient conditions are derived to ensure the exponential stability of mild solution in the mean square moment. The results are obtained by utilizing the fractional power of operators and the semigroup theory. Finally, an example is presented to demonstrate the effectiveness of the proposed result.
EXPERIMENTAL AND DENSITY FUNCTION THEORY CALCULATIONS TO INVESTIGATE THE ADSORPTION OF AN ANTI-INFLAMMATORY DRUG ON ALUMINUM SURFACE IN ACID SOLUTION
(NACE - International Corrosion Conference Series, 2016-03-06) Monisha, R; Sowmya, Ramkumar
The literature dealing with aluminium behavior in acid media in the presence of an anti-inflammatory drug is studied in order to understand its action mechanism, protective film formed and the possibility of its application according to the inhibition efficiency achieved. Aceclofenac, an anti-inflammatory drug is studied and its inhibitive performance on aluminium corrosion was studies by both dry and wet lab studies. Dry lab process using DFT is used to explore the relationship between the inhibitor molecular property and its inhibition efficiency. Wet lab studies have been carried out using weight loss, Tafel polarization and impedance measurements to evaluate their inhibitive performance in both 1M HCl and 0.5M H2SO4. PZC were calculated from impedance studies in order to understand the mechanism of inhibition. Polarization studies prove mixed type of inhibition. Good inhibition efficiency from weight loss studies was evidenced in both the acid medium, furnishing an inhibition efficiency of more than 80 %. The inhibition effect results from the adsorption of the inhibitor molecule via the lone pair of electrons on the hetero atoms together with the adjacent aromatic ring, on the metal surface forming a protective complex film. According to the results summarized, aluminium corrosion can be successfully inhibited by the drug used in the study in both the acid solutions. Results obtained from dry lab process are in good agreement with those recorded from wet lab experiments.
GRAPH CUT BASED SEGMENTATION METHOD FOR TAMIL CONTINUOUS SPEECH
(Springer Link, 2016-11-23) Laxmi Sree, B R; Vijaya, M S
Automatic segmentation of continuous speech plays an important role in building promising acoustic models for a standard continuous speech recognition system. This needs a lot of segmented data which is rarely available for many languages. As there are no industry standard speech segmentation tools for Indian languages like Tamil, there arises a need to work on Tamil speech segmentation. Here, a segmentation algorithm that is based on Graph cut is proposed for automatic phonetic level segmentation of continuous speech. Using graph cut for speech segmentation allows viewing speech globally rather locally which helps in segmentation of vocabulary, speaker independent speech. The input speech is represented as a graph and the proposed algorithm is applied on it. Experiments on the speech database comprising utterances of various speakers shows the proposed method outperforms the existing methods Blind Segmentation using Non-Linear Filtering and Non-Uniform Segmentation using Discrete Wavelet Transform.