Kinetics & Mechanism of Reaction of 4-t-Butylphenol with Formaldehyde Using Alkali Catalysts

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Spectrophotometric Studies of 2-Methylol-4- tert-butylphenol- Fe(III) Complex

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Application of sophisticated look-up tables with 12-sectors for vector control of induction motor drive

The control of Induction motor drives constitutes a vast subject and with the advent of latest technologies like vector control, direct torque control etc., these drives have been playing a vital role in the industries for variable speed applications. The control strategies of induction motor drives are more complex than DC drive control strategy. This is because in AC drives variable frequency, variation of machine parameters occurs. The various control strategies for the inverter fed induction motor have provided good steady state but poor dynamic response. To overcome the problem of undesired ripples in current, torque and flux during steady state in FOC, a new method is employed in this paper that generates the stator current more accurately by applying the active voltage vector or zero voltage vectors using switching table within a sampling interval. Based on the output of controllers and position of stator current, an optimum look-up table is constructed. This approach gives faster torque response like in vector control methods and it also reduces ripples as in DTC method. To validate the proposed method numerical simulations have been carried out and compared with the existing algorithms. The simulation results confirm the effectiveness of the proposed method. Key Words? Induction Motor Drive, Look-up table, Vector Contro

NOVEL PYRAZOLINES: SYNTHESIS AND EVALUATION OF THEIR DERIVATIVES WITH ANTICANCER AND ANTI-INFLAMMATORY ACTIVITIES

Objective: Synthesis of novel pyrazolines (P2-P4 & P7-P9) from the chalcones (C2-C10) obtained by condensing different aldehydes with 2-acetyl- 5-bromothiophene and evaluates them for in vitro anticancer and anti-inflammatory activities.Methods: The synthesized pyrazolines and chalcones were screened for anticancer activity against human breast cancer cell lines-MCF-7 and MDA-MB-468 in the range of 100 nm to 100 µm. Inhibition of bovine albumin denaturation and heat-induced hemolysis in vitro methods were followed to screen for anti-inflammatory activity. The structures of synthesized compounds were confirmed based on the IR, 1H NMR and mass spectral data.Results: Among the synthesized compounds, methoxy trisubstituted pyrazoline derivative (P6) exhibited an interesting profile of anticancer activity against MCF-7 cell line with GI50<0.1 μ M. similar to that of the standard drug doxorubicin. Compounds C8, P8, P3 have moderate anti-inflammatory activity in bovine denaturation and heat induced hemolytic method.Conclusion: Novel pyrazolines and chalcones were synthesized and evaluated for anticancer and anti-inflammatory activity. The methoxy containing compounds one of which P6 found to be active against MCF-7 breast cancer cell line. The chloro-substituted compounds found to show anti-inflammatory activity.Â

Effect of series resistance and interface state density on electrical characteristics of Au/SiO2/n-GaN Schottky diodes

metal-insulator-semiconductor (MIS) Schottky diodes and compared with (Au/n-GaN)metal-semiconductor (MS) Schottky diode. The effect of SiO2 on the surface preparation of n-GaN (MIS) Schottky diode is analyzed. The extracted Schottky barrier height and ideality factor of the MS Schottky diode is found to be 0.79 eV and 1.45 respectively. It is observed that the Schottky barrier height increases to 0.86 eV and ideality factor decreases to 1.3 for MIS diode. The interface state density as determined by Terman’s method is found to be 3.79 × 1012 and 3.41 × 1010 cm - 2 eV - 1 for the MS and MIS Schottky diodes, respectively. In addition, the values of series resistance (Rs) are determined using Cheung’s method. The I - V characteristics confirmed that the distribution of Nss, Rs and interfacial layer are important parameters that influence the electrical characteristics of MIS Schottky diodes. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2222

Geospatial Technologies in the extraction of Groundwater Potential Zones

The utmost source which is contributing to the supply of water to the society is groundwater. Depletion of undergroundwater is enormously caused by eruptive growing rate of human population along with needs in the form of industrialand urbanized growth, indigent practices in irrigation methods and deforestation. As surface fresh water is very limit, waterdemand is drastically increasing for the needs. In this connection, there is immense predominant for the natural sourcecalled groundwater. It is mandatory for the communities not only to targeting the resource called groundwater but also toprovide remedial measures to replenishment the groundwater. Enormous investigations are in the process globally, to meetthe requirement to compensate resource for the needs in all aspects. Geospatial techniques are playing vital role in theextraction of groundwater resources by means of spatial and temporal data variations along with its integration analysis inthe form of separable layers to derive the solutions. In this connection, Nandyal mandal of Kurnool is selected to demarcatethe potential zones of groundwater by using this geospatial technology.The main motto of the research work is to identifythe effective potential groundwater zones by applying methodsand integration techniques of Geographic InformationSystem and remote sensing. This gives more information for the planning and management of the ground water.Byemploying geospatial technologies, the integrated composite output for potential zones is demarcated with help of keyparameters such as drainage, lineament, slope, geology, geomorphology, land use land cover and existing groundwaterlevels. All these thematic layers are extracted by using the satellite data and other available sources by using remote sensingand GIS. All these themes are demarcated using basic elements to identify the respective classes. Proper weightages areassignedtoeachclassofallthemesintheformofseparatecategorybasedonimportanceofweightagefromexcellenttopoor based on suitability to avail the groundwater sources. This process is applied for the considered themes and isreclassified based on results. It is then integrated with weighted overlay operation in ARCGIS environment. Appropriateweightage percentages which are equal to 100%, are given prior to overlay analysis of hydrology tools of ArcGIS. Variouszones like excellent, very good, good, moderate, poor are categorized for the integrated potential zones of groundwatersource. The use of suggested methodology is applied and demonstrated for a selected case study area in Nandyal Mandal ofKurnool District of Andhra Pradesh, India. Integrated output layout will be effectively useful in the demarcation of potentialresource zones. This demarcation area zone system is not only to identify the zones but also helpful in the replenishing theresources of the study area. The digital elevation model is also used to extract slope and drainage themes of the study area.The groundwater potential zones were obtained by overlaying all the thematic maps in terms of weighted overlay analysismethod using the spatial analysis tool in ArcGIS 10.1. This ground water potential information will be useful for effectiveidentificationofsuitablelocationsfor extractionofsuchgroundwater

DC conductivity and Seebeck coefficient of nonstoichiometric MgCuZn ferrites

Nonstoichiometric series of Mg0.5-xCuxZn0.5Fe1.9O4-δ where x = 0.0, 0.1, 0.15, 0.2 and 0.25 has been synthesized by conventional solid state reaction route. The single phase spinel structure of the double sintered ferrites was confirmed by X-ray diffraction patterns (XRD). The ferrite series was studied in terms of DC electrical conductivity and thermoelectric power in the temperature ranging from room temperature to 300 °C and 400 °C, respectively. It was observed that DC electrical conductivity and Seebeck coefficient α decreased with the increase in x. DC electrical conductivity was found to decrease by about 4 orders. All the compositions showed a negative Seebeck coefficient exhibiting n-type semiconducting nature. From the above experimental results, activation energy and mobility of all the samples were estimated. Small polaron hopping conduction mechanism was suggested for the series of ferrites. Owing to their low conductivity the nonstoichiometric MgCuZn ferrites are the best materials for transformer core and high definition television deflection yokes. © 2017 Wroclaw University of Science and Technology

Incidentally detected solid pseudopapillary neoplasm of pancreas in a child with an ovarian cyst: a case report

Solid pseudopapillary neoplasms (SPN) are the most common as well as very rare pediatric tumors of the pancreas. Most of the literature is derived from adult SPNs. As per world health organization, these tumors considered as low grade malignant with excellent survival outcomes after complete surgical resection. We report a case of incidentally detected SPN in a 16-year-old female child with an ovarian cyst. She underwent pylorus preserving pancreaticoduodenectomy and ovarian cystectomy. Histopathology revealed well differentiated SPN of the pancreas head and ovarian cystadenoma. She is symptom-free at the 6th month follow up

Fuzzy logic controller based DC-Link Voltage Self-Balance Method for Multilevel Converter with less Number of Voltage Sensors

In many inverters, Voltage balance of dc-link capacitors is very important for applications of a cascade multilevel converter or a modular multilevel converter. In this paper, a novel diode-clamped modular multilevel converter (DCM2 C) topology is proposed and a power feedback control method is developed with fuzzy logic controller. With the developed control strategy, the proposed diode-clamped circuit becomes controllable closed loop which enables the capacitor voltages to be clamped by low power rating clamping diodes. The proposed topology and control strategy has quicker response with transient state error reduction and requires much fewer voltage sensors than the normally used traditional method of multilevel inverters as diode clamped inverters; therefore, the system performance improvement and cost reduction are expected. Based on the proposed DCM2 C, a novel N +1-level cascade multilevel topology is proposed for a cascade active power filter (CS-APF). The Proposed fuzzy logic controller is implemented to get study state response at dc voltage capacitors, therefore to get balanced load outputs. The simulation results from the CS-APF have demonstrated and verified the effectiveness of the proposed novel topology and control method