Search

The paper proposes a new stochastic multiobjective technoeconomic model for integrating photovoltaic (PV) and wind energy resources in electricity price (EP)‐driven distribution systems. The primary goal of this paper is to determine the optimal location and capacity for renewable energy‐based distributed generation, specifically PV and wind resources, while considering weather and system uncertainties. These uncertainties include stochastic variations in PV illumination intensity, wind speed, EP, and load fluctuations. To address these uncertainties, the paper employs scenario modeling techniques named as Latin hypercube sampling with Cholesky decomposition. This technique generates multiple correlated scenarios that represent uncertain variables. Subsequently, a scenario reduction technique is applied to identify the scenario with the highest probability. Later, a mathematical model is developed to minimize an objective function that encompasses various factors like system losses, node voltage deviations, the cost of purchasing power from the grid; and simultaneously maximize the total annual energy savings. The objective is to find optimal solutions that strike a balance between different objectives. To obtain an efficient optimum solution, this paper employs an effective meta‐heuristic technique named as JAYA algorithm. The results obtained by the JAYA algorithm are juxtaposed with those obtained using particle swarm optimization and genetic algorithm techniques. The proposed method is evaluated using Institute of Electrical and Electronics Engineers (IEEE) 33‐node and IEEE 69‐node test feeders to validate its feasibility and effectiveness. However, the effectiveness of the proposed method is not limited to any size of test systems. [ABSTRACT FROM AUTHOR]

Recent studies have challenged the validity of the Redfield ratio. It is proposed that physical and biogeochemical processes govern the geographical variations in carbon : nitrogen : phosphorus (C : N : P) ratios. However, this proposal remains to be examined through concurrent observations of C : N : P ratios with physical and biogeochemical processes in various marine reservoirs. Here, we sampled the Arabian Sea for its C, N, and P content in organic and inorganic pools during the winter monsoon. We analyzed the role of convective mixing, eddies, and N2 fixation to explain the variation in observed elemental ratios. Convective mixing injected the cold water and enhanced the supply of N and P nutrients in the top layer (surface to 50–75 m) of the northern Arabian Sea. This led to a decrease in the N : P and C : P ratios in the particulate organic matter in the northern region, but C : N : P increased equatorward, averaging 245 : 32 : 1 in the top layer of the Arabian Sea. The variation in the elemental ratios in the top layer is best explained by the changes in water temperature. N2 fixation contributed negligibly to the N : P ratio of the export flux. The substantial decrease in N : P ratios of nutrients in the subsurface waters is most likely caused by the denitrifying conditions in the Arabian Sea. As the processes of convective mixing and eddies are are prevalent oceanic processes, our observations underpin that the interplay of these processes leads to changes in the elemental ratios globally. [ABSTRACT FROM AUTHOR]

Byline: Bhagyashree. Supekar, Rajesh. Soni, Ravi. Bhushan, Jayesh. Mukhi, Rajesh. Singh, Dharitri. Bhat Lazarine leprosy is an unusual expression of usually borderline tuberculoid (BT) form characterized by spontaneous ulceration of [...]

A thin Nb target on a Pb backing was fabricated using the rolling technique. In the present work, the characterization of the sample has been carried out using various techniques to study the surface morphology, crystallography, elemental analysis, thickness and electrical conductivity useful for the intended use of the target prepared. The thin Nb target was analyzed using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and Rutherford back-scattering spectroscopy (RBS) techniques. The uniform and smooth surface of the sample was confirmed by SEM imaging. The presence of oxygen in the EDS spectra and peaks corresponding to crystal planes of PbO2 in the XRD spectrum confirms the oxidation of Pb foil. The XRD spectrum shows clear peaks corresponding to (011), (002), (112) crystal planes of pure Nb. The thickness of the thin Nb foil measured using the RBS techniques was found to be 0.8 mg/cm2. The current(I)-voltage(V) curve (relationship between the current flowing through an electronic device and the applied voltage across its terminals) at room temperature for the Pb and Nb/Pb foils was plotted and showed linear relationship between applied voltage and current flowing through the target foil. The measured electrical conductivity indicates an enhancement of 35.9 % for Nb/Pb foil relative to the conductivity measured for the Pb foil.

Indapamide (Indp) and certain other diuretics have been abused in sports, therefore, having sensitive methods for its detection and assay in biological fluids (whole blood, plasma, serum, and urine) is of significant importance. The racemic mixture of Indp is being used as an active pharmaceutical ingredient among other commonly prescribed diuretics. The regulatory authorities and pharmaceutical industries demand analytical methods for successful enantioseparation of such molecules. The paper presents a critical overview of the scientific issues of the application of contemporary techniques involving various chromatographic approaches (with liquid or supercritical fluid as mobile phases) and capillary electrophoresis and method development, for drug screening, assay, bioequivalence studies and enantioseparation of indapamide with their results. It also covers the historical developments that led to significant breakthroughs in research and concise evaluations of research in the area. Different types of chromatographic methods (HPLC, CEC, SFC etc) discussed herein provide an insight and a choice to select a method to (i) screen Indp for drug abuse, (ii) separate, isolate and quantify the enantiomers of Indp and (iii) investigate their pharmacokinetics as markedly different species and not as a total drug. The article evaluates the field's status with a broad base and practical oriented approach so that the underlying principles are easily understood to help chemists and non-specialists gain useful insights into the field outside their specialization and provide experts with summaries of key developments. To the best of authors' knowledge there has been no attempt to review such methods for analysis of Indp and this is the first report of its kind. [ABSTRACT FROM AUTHOR]

Worldwide thin layer chromatography (TLC) is still in very much use in various different application fields (e.g. natural products chemistry, monitoring the organic/enantioselective synthesis, and routine analysis in analytical laboratories). Herein is presented an account of the efficient resolution/enantioseparation of racemic and non-racemic mixtures of several different types of active pharmaceutical ingredients, and biologically important compounds by TLC using a direct approach along with quantitative determination and isolation of native forms via non-covalent diastereomer formation. Different approaches and mechanisms of direct enantioseparation using different chiral reagents are discussed. It provides a route for a wide range of chiral stationary phases (CSPs) which can be in-home thought out, produced, assessed, and customized. The achievements and new challenges in the field are presented. Besides, it presents a very useful coverage for the non-specialists to the subject who want to understand where this study fits into the existing literature in this general area. [ABSTRACT FROM AUTHOR]