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The trend of increasing demand creates a gap between generation and load in the field of electrical power systems. This is one of the significant problems for the science, where it require to add new generating units or use of novel automation technology for the better utilization of the existing generating units. The automation technology highly recommends the use of speedy and effective algorithms in optimal parameter adjustment for the system components. So newly developed nature inspired Bat Algorithm (BA) applied to discover the control parameters. In this scenario, this paper considers the minimization of real power generation cost with emission as an objective. Further, to improve the power system performance and reduction in the emission, two of the thermal plants were replaced with wind power plants. In addition, to boost the voltage profile, Static VAR Compensator (SVC) has been integrated. The proposed case study, i.e., considering wind plant and SVC with BA, is applied on the IEEE30 bus system. Due to the incorporation of wind plants into the system, the emission output is reduced, and with the application of SVC voltage profile improved. [ABSTRACT FROM AUTHOR]

Nowadays, improvement in power system performance is essential to obtaine economic and technical benifits. To achieve this, optimize the large number of parameters in the system based on optimal power flow(OPF). For solving OPF problem efficiently, it needs robust and fast optimization techniques. This paper proposes the application of a newly developed hybrid Whale and Sine Cosine optimization algorithm to solve the OPF. It has been implemented for optimization of the control variables. The reduction of true power generation cost, emission, true power losses, and voltage deviation are considered as different objectives. The hybrid Whale and Sine Cosine optimization is validated by solving OPF problem with various intentions using IEEE30 bus system. To varidate the proposed technique, the results obtained from this are compared with other methods in the literature. The robustness achieved with the proposed algorithm has been analyzed for the considered OPF problem using statistical analysis and whisker plots. [ABSTRACT FROM AUTHOR]

The melt quench approach is used to create a transition metal-doped glass material by adjusting the concentration of vanadium and lithium carbonate with a unique chemical composition. The main objectives of the present investigation are to identify basic structural units in the prepared samples, to investigate the impact of glass composition on structural changes, to relate the structural changes with the change in properties of glasses, and to find the suitability of the samples from the perspective of optical applications. The main novelty of these glasses is that the lithium carbonate is varied along with the V2O5 for optical applications. The highest dopant 1 mol percent material has a density of 3.6666 gm/cc and a refractive index of 1.56, indicating its suitability for optical applications. The glass melting temperature (Tg) of the test sample is 808.09 °C, and Hruby's criteria value (KH) is 0.2565, inferring that the glass material is stable. For loads of 50 g and 100 g, the Vickers micro-hardness improved when the dopant was increased, while for 200 g, the hardness value declined. As the stress on the material rose from 10 to 30 N, the coefficient of friction drops from 0.632 to 0.002, the specific wear rate increased from 6.64 × 10−5 to 39.06 × 10−5 mm3/N-m, and the specific wear energy decreased from 22.44 to 0.81 MJ/g. In the visible area, the material's optical absorption for the greatest dopant is 548 nm, and in the infrared region 738 nm. The direct and indirect band gaps of the current investigated material for the highest dopant are 2.03 eV and 1.88 eV, respectively, proposing that the sample is a semiconductor. Optical transmission measures find the material's suitability as a bandpass filter in the visible range at 415.33 nm and 417 nm, respectively, with FWHW of 0.35 nm and 1.22 nm for the highest dopant sample. [ABSTRACT FROM AUTHOR]

Optimal power flow with generation reallocation is a suitable method for better utilization of the existing system. In recent years, Flexible AC Transmission System (FACTS) devices, have led to the development of controllers that provide controllability and flexibility for power transmission. Out of the FACTS devices unified power flow controller (UPFC) is a versatile device, capable of controlling the power system parameters like voltage magnitude, phase angle and line impedance individually or simultaneously. The main aim of this paper is to minimize real power losses in a power system using BAT search algorithm without and with the presence of UPFC. Minimization of real power losses is done by considering the power generated by generator buses, voltage magnitudes at generator buses and reactive power injection from reactive power compensators. The proposed BAT algorithm based Optimal Power Flow (OPF) has been tested on a 5 bus test system and modified IEEE 30 bus system without and with UPFC. The results of the system with and without UPFC are compared in terms of active power losses in the transmission line using BAT algorithm. The obtained results are also compared with Genetic algorithm (GA). [ABSTRACT FROM AUTHOR]

Investigation for high yielding water wells in the khondalitic terrain (graneti ferrous silliminite gnesiss) is mostly faced with the problem of identification of the extent of the depth of kaolinisation of the aquifer. The traditional Vertical Electrical Sounding survey, Seismic Refraction survey and Very Low Frequency Electromagnetic survey could not identify the kaolinisation of the aquifer in the present investigations. The Two Dimensional (2D) Resistivity and Induced Polarization (IP) Imaging surveys are attempted for the identification of kaolinised layer and depth of kaolinisation. Number of 2D Resistivity and IP Imaging profiles were conducted near Chipurupally in Vizianagaram district of Andhra Pradesh, India along successful and failed wells located within short distances. Resistivity and IP measurements were carried out using an ABEM SAS 4000 Terrameter. The resistivity and I.P. images have provided a clear view of the thickness of the highly weathered zone (kaolinised zone) at both successful and failed wells. The highly weathered zone is identified with the resistivity values below 25 ohm.m. The depth of highly weathered material at failed well is extended about 8-10 m more deeper than the successful wells at some places to as much as 20 m more deep at some other places. This extended deeper kaolinisation of the aquifer is responsible for failure of wells. Layers having resistivities between 25-65 Ohm.m are identified as aquifer layers which are composed of moderately weathered and fractured khondalitic suit of rocks (Garnti ferrous sillimanite/biotite gneiss). Layers with resistivities greater than 65 Ohm.m are interpreted to have basement characteristics belonging to the granite gneiss. Interestingly IP imaging has not provided any greater insights in delineating the kaolinistion of the aquifer when compared to resistivity Imaging, in fact resitivity imaging has shown greater depths of kaolinisation than IP Imaging. [ABSTRACT FROM AUTHOR]

Abstract: Radicamine B 5 was synthesized from p-hydroxy benzaldehyde 7 stereoselectively using acid catalysed amido cyclisation with the help of neighbouring group participation (NGP). Without NGP both radicamine B 5 and its epimer 5-epi radicamine B 6 were obtained. The key steps of the synthesis are Sharpless asymmetric dihydroxylations and acid mediated amido cyclisation. [Copyright &y& Elsevier]

Abstract: The highly stereoselective Grignard addition on chiralimine 8 and opening of chiral epoxide 9 with Grignard reagent have been used as key steps in the stereoselective synthesis of cytotoxic anhydrophytosphingosine pachastrissamine (jaspine B) and N,O,O,O-tetra-acetyl d-lyxo-phytosphingosine. [Copyright &y& Elsevier]

Abstract: A common and stereoselective strategy for the synthesis of N,O,O,O-tetra-acetyl d-ribo-(2S,3S,4R)-phytosphingosine and 2-epi-jaspine B was achieved by using Grignard addition on N-benzyl sugar lactamine and Wittig olefination as key steps. [Copyright &y& Elsevier]

Abstract: A new stereoselective approach for the synthesis of N-benzyl amino(hydroxymethyl)cyclopentitols by using stereoselective allylation on lactamine and RCM from d-ribose has been described and the glycosidase inhibitory activities of these amino cyclopentitols have been studied. [Copyright &y& Elsevier]

Abstract: Nd3+ doped fluorine containing zinc-aluminophosphate glasses have been prepared with alkali and alkaline earth content to understand the effect of network modifiers on radiative process. The physical and optical properties of these glasses have been evaluated. The Judd–Ofelt model for the intensity analysis of induced electric dipole transitions has been applied to the measured oscillator strengths of the absorption bands to determine the three phenomenological intensity parameters Ω 2, Ω 4 and Ω 6 for each glass. Using these parameters, transition probability (A), total transition probability (A T), branching ratios (β R) radiative life times (τ R) and integrated cross-section (σ a) for the stimulated emission have been theoretically calculated for certain excited Nd3+ fluorescent levels. From the obtained results the conclusion is made about the possibility of using these glasses as laser material. [Copyright &y& Elsevier]

Abstract: A short synthesis of hydroxyethylene dipeptide isostere, a core unit of the HIV-protease inhibitors ritonavir and lopinavir, its C-3 epimer and C 2 symmetric diamino diol is described. The crucial aspects of the synthesis are self-cross metathesis and exploitation of C 2-symmetric of the metathesis product 8 to obtain the required skeleton. [Copyright &y& Elsevier]

Abstract: An efficient and highly stereoselective approach to bicyclic aza sugars is described using Grignard reaction on an N-benzyl imine derived from 3-O-benzyl-1,2-O-isopropylidine-α-d-xylo-pentodialdofuranose, ring closing metathesis, and reductive cyclization as key steps. [Copyright &y& Elsevier]

Abstract: A novel stereoselective synthesis of N-Boc-(2S,3S)-3-hydroxy-2-phenylpiperidine was achieved from d-mannitol involving the highly stereoselective addition of phenyl Grignard to an allyl imine (de >98%) and ring-closing metathesis (RCM) in the key steps. [Copyright &y& Elsevier]

Abstract: A Chiron approach for the synthesis of (+)-secosyrin 1 from d-mannitol has been described. The key steps are a stereoselective Wittig reaction and an intramolecular Michael addition on the disubstituted butenolide, leading to a highly stereoselective formation of the tertiary chiral centre of (+)-secosyrin 1. [Copyright &y& Elsevier]

A series of trivalent gadolinium (Gd3+) doped lanthanum phosphates (LaPO 4) were prepared by the co-precipitation technique with varying concentrations of Gd3+. The structural properties of the prepared phosphor samples were analyzed by X-ray diffraction (XRD) which showed monoclinic structure of LaPO 4. The photoluminescence (PL) emission spectra of the Gd3+-doped phosphor excited at 272 nm consists of dominant UVB emissions at 312 nm corresponding to the P 7 / 2 → 8 S 7 / 2 6 transitions of Gd3+. The electron spin resonance (ESR) spectra of LaPO 4 :Gd3+ phosphor reveal three significant attributes with effective g-values around 6, 2.8, 2.0 and a feeble characteristic at 4.8 owing primarily to the presence of Gd3+ ions in clustered species. [ABSTRACT FROM AUTHOR]

Abstract: The stereoselective synthesis of 6-epi-pentenocin B 3 is described using a stereoselective Grignard reaction and ring-closing metathesis (RCM) as the key steps. [Copyright &y& Elsevier]

Asymmetric syntheses of (1R,1′R,5′R,7′R) and (1S,1′R,5′R,7′R)-1-hydroxy-exo-brevicomins 1 and 2, volatiles of the male mountain pine beetle, and a formal synthesis of (+)-exo-brevicomin 3, a component of the attracting pheromone system of several bark beetles have been achieved. The key steps are Birch reduction of commercially available α-picoline, selective Wittig olefination, and Sharpless asymmetric dihydroxylation. [Copyright &y& Elsevier]

A stereoselective synthesis of 1,4-dideoxy-1,4-imino-d-allitol 1 and formal synthesis of (2S,3R,4S)-3,4-dihydroxyproline was achieved via the addition of vinylmagnesium bromide to the benzylimine derived from (R)-2,3-O-isopropylidene glyceraldehyde followed by N-allylation, ring-closing metathesis (RCM), and dihydroxylation. [Copyright &y& Elsevier]

An efficient and stereoselective synthesis of protected (2R,3R,4S)-4,7-diamino-2,3-dihydroxyheptanoic acid, a constituent of the depsipeptides, callipeltins A and D, from d-ribose is described. [Copyright &y& Elsevier]

An efficient synthesis of enantiopure (−)- and (+)-pentenomycins are described by reductive iodo elimination and ring-closing metathesis (RCM), as the key steps. The first synthesis of the unnatural (+)-isomer is described. [Copyright &y& Elsevier]

Enantioselective synthesis of non-peptidic neurokinin NK1 receptor antagonist L-733,060 is described using ring-closing metathesis as a key step, starting from l-phenylglycine. [Copyright &y& Elsevier]

Abstract: A common method for the synthesis of 4a-carba-β-l-lyxofuranose and 4a-carba-β-l-arabinofuranose from d-mannose and 2,2,5-trimethyl-3a,6a-dihydro-cyclopenta[1,3]dioxol-4-one from d-ribose is described using catalytic Nozaki-Hiyama-Kishi (NHK) conditions and ring closing metathesis (RCM). In this transformation, ω-deoxy-ω-iodo manno/ribo furanoside undergoes reductive elimination in the presence of Mn/CrCl3 to give the corresponding olefin-aldehyde which was trapped by nucleophile under the same conditions to afford the desired diolefinic species. The ring closing metathesis reaction on these diolefinic species with Grubbs second generation catalyst produced the required carbocycles. [Copyright &y& Elsevier]

The ultrasonic velocity and density of binary liquid mixtures of quinoline with o-xylene, m-xylene, and p-xylene have been measured over the entire range of composition at T = 303.15, 308.15, 313.15, and 318.15 K. Using these data, various parameters like adiabatic compressibility (β), intermolecular free length (Lf ), and acoustic impedance (Z) and some excess parameters like excess adiabatic compressibility (βE), excess intermolecular free length (LEf), excess acoustic impedance (ZE), and excess ultrasonic velocity (uE) have been calculated for all the three mixtures. The calculated deviations and excess functions have been fitted to Redlich-Kister polynomial equation. The observed deviations have been explained on the basis of the intermolecular interactions present in these mixtures. [ABSTRACT FROM AUTHOR]

Abstract: A new strategy for the synthesis of 1,2-dideoxy iminosugar C-glycosides and indolizidines involving highly stereoselective [2,3]-Wittig rearrangement from Garner aldehyde has been developed. This rearrangement yielded an optically pure, highly functionalized key intermediate, which has been further utilized for the synthesis of 5-epi-ethylfagomine, 2-epi-5-deoxyadenophorine, and 5-hydroxymethyl indolizidine. [Copyright &y& Elsevier]

Abstract: A short and stereoselective synthesis of (−)-codonopsinol 5 and its C-2 epimer 6 were accomplished from commercially available starting material d-1,5-gluconolactone, using acid mediated amido cyclisation as the key step. The inhibitory activitiy of these compounds against glucosidase and galactosidase has been studied. [Copyright &y& Elsevier]

A common strategy for the synthesis of (−)-chloramphenicol and (+)-thiamphenicol is described. These antibiotics have been synthesized from commercially available 4-nitrobenzaldehyde and 4-(methylthio)benzaldehyde in three and four steps, respectively. [Copyright &y& Elsevier]

A versatile and efficient method for the preparation of (2S)-2-(hydroxymethyl)-N-Boc-2,3-dihydro-4-pyridone from l-(−)-phenylalanine 2 utilising the aromatic system as a masked β-keto aldehyde was developed. The key step in the sequence is an intramolecular cyclisation of 6 to give 2,3-dihydropyridin-4-ones. [Copyright &y& Elsevier]

Green and efficient one-pot three-component synthesis of novel 2-(7-amino-2,2-dimethyl-4-oxo-5-phenyl-4,5-dihydropyrano[2,3- d][1,3]dioxin-6-ylcarbonyl)-2,3-dihydrophthalazine-1,4-diones have been developed by condensing 3-(1,4-dioxo-1,2,3,4-tetrahydrophthalazin-2-yl)-3-oxopropanenitrile with benzaldehydes and Meldrum's acid using L-proline as catalyst in ethanol at room temperature. The products have been isolated as pure compounds in good yields without using column chromatography. [ABSTRACT FROM AUTHOR]

Diversity oriented concise asymmetric syntheses of l -2,3- trans -3,4- cis -dihydroxyproline and (3 S ,5 S )-3,4,5-trihydroxypiperidine have been developed from ( R )-glycidol. The key step of the synthesis is Sharpless asymmetric dihydroxylation on enantiomerically pure TBDMS protected allylic alcohol 14 which generates the triol intermediate 15 in excellent de . The (2 R ,3 R ,4 S )-2,3-dihydroxypentanoate derivative 15 was subsequently converted to natural pyrrolidine azasugar 1 and non-natural piperidine azasugar 4 under cascade reaction conditions in good yields. [ABSTRACT FROM AUTHOR]

A concise synthesis of (2 R ,4 R )-4-hydroxyproline ( 1 ) and (2 S ,4 S )-4-hydroxyproline ( 2 ) has been developed in enantiomerically pure form from commercially available starting materials with excellent diastereoselectivity. The tightly bound chelation controlled transition state formed during the 5- exo - tet ring closure reaction is assumed to be the origin of high diastereoselectivity. [ABSTRACT FROM AUTHOR]

A novel, stereo selective synthesis of (−)-cytoxazone 1a and stereoselective synthesis of (+)-5-epi-cytoxazone 1b were achieved via stereoselective Grignard addition of vinylmagnesium bromide on N-Boc al ehyde obtained from p-hydroxy-d-phenylglycine 2 followed by cyclization of N-Boc alcohol 6, ozonolysis and reduction to get (+)-5-epi-cytoxazone. Compound 6 underwent mitsunobu conditions, deprotection of ester followed by cyclization of N-Boc alcohol to get (−)-cytoxazone. #IICT Communication Number: 020616. [ABSTRACT FROM AUTHOR]

This study discusses the impact of high-resolution winds on the coastal waves and analyses the effectiveness of the high-resolution winds in recreating the fine-scale features along the coastal regions during the pre-monsoon season (March–May). The influence of the diurnal variation of winds on waves is studied for the Tamil Nadu coastal region using wind fields from weather research and forecast (WRF) (3 km) and European Centre for Medium-Range Weather Forecasts (ECMWF) (27.5 km). The improvement in the coastal forecast is then quantified with wave rider buoy observations. The high-resolution wind fields simulated fine-scale features like land–sea breeze events and showed good agreement with observation results. The error in the wave height and period is reduced by 8% and 46%, respectively, with the use of high-resolution forcing winds WRF over ECMWF, although the overestimation of wave energy on high frequencies due to overestimated WRF winds remains as a challenge in forecasting. The analysis also shows the importance of accurate wave forecast during a short-duration sudden wind (~12 m/s) occurrence in southern Tamil Nadu near Rameswaram during the pre-monsoon period. Low pressure forms over Tamil Nadu due to the land surface heating, resulting in a sudden increase of winds. High winds and steep waves which cause damage to the property of the coastal community near Rameswaram also were well simulated in the high-resolution forecast system with WRF winds. [ABSTRACT FROM AUTHOR]