Physics, Astronomy, Optics and Photonics
Developing a New Method for the Estimation of Valsartan (VST) in Pharmaceutical Dosage Samples by Using Diazotization and Coupling Reactions Spectrophotometrically
A new method for valsartan (VST) estimation in pharmaceutical dosage samples by spectrophotometry was developed.
The method was based on the formation of coloured dye by the diazotization reaction of 3-amino-2-naphthol with sodium nitrite in an acidic medium to form diazonium compounds which were then coupled with VST in a basic medium.
The drug sample showed linearity in the range 4.6 - 24.2 μgmL-1 and the λmax was found at 432nm. Sandell’s sensitivity (9.950×10-3) Molar absorbtivity (Ɛ= 4.377×104) regression equation (y= 0.0775x + 0.0041) correlation coefficient (r2= 0.968) detection limit (DL= 0.668) and quantitation limit (QL= 2.024) were evaluated.
The percentage recovery of the drug samples was found to be 100%. This method successfully determined VST in Pharmaceutical dosage samples.
Advancements of Lanthanide-doped Phosphors in Solid-state Lighting Applications
The challenge of energy conversion and enhancement has been a problem in the world of lighting technologies as the population and global industrialization grow rapidly. Solid-state lighting (SSL) has proven to be a better alternative in the illumination industry because of its environmentally friendly and high energy efficiency. Lanthanide-doped phosphors have gained global attention in SSL because they have versatile applications with enhanced overall performance and luminescence. This review delves into the advancement in lanthanide-doped phosphors for Solid-state lighting (SSL) applications. It discusses the in-depth analysis of how to tailor the crystal lattice design optimize the host material for emission efficiency and minimize the non-radiative pathways. This paper further discusses the lanthanide-doped phosphor composition strategies to obtain desired emission spectra and enhanced color rendering index with the Energy transfer mechanism and the synthesis techniques. This review also addresses 3 processes for expanding the light spectrum current challenges future directions and emerging trends present in the lanthanide-doped phosphor in Solid-state lighting (SSL) applications.
NiO@PANI based Nanocomposites as an Advanced Functional Material: Experimental and Computational Approach
Individually metal nanoparticles (NPs) and conducting polymers show unique properties due to small size large surface area and high order of conductivity. But their combination may result in a synergistic effect in properties.
The NiO NPs and conducting polymer Polyaniline were prepared by modified Sol-gel and chemical oxidative methods respectively. Powder XRD FTIR TEM and UV-visible methods were used for the structural evaluation. The computational (DFT) study was performed to support experimental results. The NiO/Polyaniline (PANI) nanocomposites (NCs) were explored as corrosion inhibitors electrical conductors and photocatalytic agents.
The NiO/Polyaniline NCs showed 91.52% corrosion inhibition efficiency at 1000 ppm concentration. The photocatalytic activity was investigated against methylene blue dye under ultraviolet light. The NiO/Polyaniline NCs decompose 90% of organic dye. The NCs exhibit good conducting corrosion inhibition and photocatalytic activity.
The metal oxide (NiO NPs) and PANI-based NCs can be used as corrosion inhibitors conducting material and for the degradation of organic compounds (dyes) in impure water.
The Mass Gap in QCD and a Restriction on Gluon Masses
In this study we prove that it is necessary to introduce the non-zero gluon masses into the fundamental Lagrangian of Quantum Chromodynamics in order to describe the mass gap in the reaction of electron-positron annihilation into hadrons. Further in this work a new restriction on the gluon masses is imposed and the renormalized theory with non-zero Lagrangian gluon masses is presented.
Advanced Gyrotron Concepts for Spectroscopic Applications
Currently some modern spectroscopic applications require sub-terahertz and terahertz continuous-wave electromagnetic radiation sources with power levels from 0.1 to 100 W. Gyrotron a powerful high-frequency vacuum electronics device is considered one of the promising sources for these aims.
Modification of the gyrotron design promotes the widespread use of these devices for DNP/NMR spectroscopy.
Promising non-canonical concepts are presented the features of which compare favorably with the classical gyrotron scheme.
The gyrotron concepts we considered allow us to master the terahertz range and develop a unique gyrotron installation for each scientific group considering the specifics of their scientific research.
High-power Microwaves Against Locust Invasion
There are a lot of phytophagous and harmful animals in agriculture and forestry in the entire world. The ultimate goal in locust control is the use of preventive and proactive methods that disrupt the environment to the least possible extent. This would make agricultural production easier and more secure in the many regions where growing crops is of vital importance.
The possibility of using high-power microwave systems to combat harmful animal pests in agriculture and forestry is discussed. The proposed method is compared favorably with respect to the environment.
The obtained results of the study demonstrated the possibility of using modern sources of high-power microwave radiation to solve the problem of insect invasion.
It should be noted that the use of powerful microwaves is a promising means of controlling locusts and other pests. Mobile international forces equipped with modern microwave apparatus can solve the problem of combating locusts and other pests on a global scale without harming the environment. Microwave systems can also be used against other phytophagous pests of agriculture and forestry.
Sputtering Heterogeneous Tungsten Carbide Targets by Light Ions Bombardment
This paper presents a model for sputtering heterogeneous two-component materials with light ions.
The model based on two sputtering mechanisms makes it possible to calculate the total sputtering coefficients of the target components and it is easily transformed for the case of sputtering different types of targets. Model testing was conducted for the case of sputtering homogeneous tungsten carbide targets with ions of different energies.
The results of the calculations are given in comparison with experimental data and the results of computer simulation. The comparison shows good agreement of the calculated values with the data of other authors. The proposed model was used to describe stationary (stoichiometric) sputtering of tungsten carbide targets. Using this model the concentrations of components in the modified target layer were calculated and the thickness of the modified layer was also estimated.
The method of calculating the concentration of target components in the modified layer and the thickness of this layer can be the basis of the technology of creating materials with given properties of the surface layer.
Variations in the Solar Modulation Parameter Over the Last 9.5 Thousand Years and the Tilt of the Geomagnetic Dipole
Calculations of the solar modulation parameter (Φ) over the past millennia typically use the relationship between the production rate of cosmogenic isotopes the earth's dipole moment and the magnitude of Φ. The cosmogenic isotopes 14C and 10Be are typically used in these studies. When studying solar modulation the cyclic change in dipole tilt is usually not taken into account which affects estimates of past solar activity.
Tree rings are a reliable basis for obtaining a radiocarbon time scale (IntCal13). However determining the concentration of 14C in tree rings is a difficult and controversial task. The time scale derived from the 10Be production rate simulation (GICC05) is less reliable. Nevertheless there is a way to combine the accuracy of the radiocarbon time scale with the reliability of estimates of the 10Be production rate. This method is the synchronization of the radiocarbon and beryllium-10 series.
We have selected the most relevant methods for calculating the solar modulation parameter Φ for the Holocene. When calculating Φ 10Be data synchronized with 14C data were used. The latest data on the earth's dipole moment were considered. Empirical Mode Decomposition (EMD) was used in the analysis of Φ.
It has been shown that the first two decomposition modes are oscillating components with periods of 710 and 208 years the amplitudes of which increase with time reaching a maximum of 2500 BP. From contemplation it follows that the 710-year oscillations are apparently caused by fluctuations in the tilt of the earth's dipole. After excluding the EMD component associated with the 710-year cyclicity a corrected series was obtained for the solar modulation parameter free from the influence of changes in the tilt of the magnetic dipole.
The rate of formation of cosmogenic radionuclides depends on the intensity of penetration of Galactic Cosmic Rays (GCRs) into the earth's atmosphere. Before reaching earth GCRs must cross the heliosphere where they are exposed to solar modulation. Adequate consideration of solar modulation parameters is important for the correct interpretation of the rate of production of cosmogenic isotopes and solar activity.
Measurement of Viscoelastic Properties by Free Loading-Mass Method
A procedure for determining the elastic and viscous properties of the sample material on the basis of the forced vibrations of a sample of mass 𝑚 loaded with a certain mass 𝑀 is developed. One of advantages of using the top mass instead of a rigid fixation is the appearance of an additional deformation resonance the frequency of which is times smaller than the resonance frequency of the fixed sample.
The experimental setup implementing the free mass method is described. Notably the proposed scheme does not require any adjustment and is assembled from standard devices. By changing the design of the sample only both shear and compression-tension strains can be measured. The combination of these methods allows measuring the complex Poisson’s ratio in addition to modulus of elasticity and loss factor.
One-dimensional (1D) and two-dimensional (2D) models of specimen deformation are considered. For the 1D deformation model approximate formulas for calculating the modulus of elasticity and the loss factor are substantiated and the limits of validity these formulas are outlined. Improving the accuracy of measurements is also considered. To do this it is necessary to fully describe the boundary conditions on the deformable sample. The developed 2D model of sample deformation made it possible to calculate the elastic modulus form factors for various samples with axial symmetry.
The method may become a Standard for measuring viscoelastic properties of materials (complex elastic and shear modulus as well as complex Poisson's ratio).
Understanding the Origins of Quark Charges, Quantum of Magnetic Flux, Planck’s Radiation Constant and Celestial Magnetic Moments with the 4G Model of Nuclear Charge
In our previous published papers considering 3 large atomic gravitational constants assumed to be associated with weak strong and electromagnetic interactions we have proposed the existence of a nuclear charge of magnitude en=2.95e and developed a nuclear mass formula associated with strong and weak interactions having 4 simple terms and only one energy coefficient.
Two important assumptions are that there exists a weak fermion of rest energy 585 GeV and strong coupling constant is the squared ratio of electromagnetic charge and nuclear charge. The aim of this paper is associated with understanding the mystery of the quantum of magnetic flux Planck’s quantum radiation constant and Reduced Planck’s constant. Proceeding further quark charges strong coupling constant nuclear stability nuclear binding energy medium and heavy atomic X-ray levels and celestial magnetic moments can be understood in a unified approach. It may also be noted that by considering the integral nature of elementary particle masses it seems possible to understand the discreteness of angular momentum.
Considering our proposed en=2.95e=3e as a characteristic nuclear charge it seems possible to understand the integral nature of quarks electromagnetic charge. With this idea neutron proton and pion decay can be understood very easily.
In all the cases the up quark of charge (±2e) seems to play a crucial role in the internal transformation of the down quark of charge (±e) and external observable elementary basic elementary particles. It needs further study at the fundamental level. Proceeding further quantum of magnetic flux Planck’s radiation constant and Reduced Planck’s constant can be understood with our 4G model of final unification.
Laboratory Analogs of Thermally Processed Ices Containing H2O, N2, NH3, CO2, and C2H3N Relevant to Astrophysical Environments
Laboratory simulations can benefit ground- and space-based observations of icy bodies in outer space. It is well-known that NH3 and CO2 can interact forming ammonium carbamate (CH6N2O2).
This study examines NH3 and CO2 in thermally processed H2O-rich ices in the laboratory via mid-infrared absorption spectroscopy. In particular the presence of CO2 in NH3-ice mixtures thermally annealed at 150 K for more than four hours in systematic experiments suggested that ammonium carbamate could potentially trap volatiles within the ice matrix.
Additional studies with acetonitrile (C2H3N) in ice mixtures containing H2O CO2 and NH3 were also performed. Absorption peak position changes were recorded when the temperature was slowly increased (≤ 5K/min) and also annealed at temperatures up to 150 K.
These studies will hopefully be useful in interpreting pre-biotic chemistry in the Solar System.
Synthesis of Optimal Control of Spacecraft Angular Momentum for Spatial Turn Taking into Account Energy Costs Using Quaternions
In this paper we propose solving the specific original problem of control synthesis of spacecraft attitude. Optimization of the control program is made with the use of a new criterion of quality that combines energy costs and duration of reorientation under restrictions on control (the presence of a time factor limits the duration of slew maneuver).
The construction of optimal control for angular momentum change is based on the quaternion method and L.S. Pontryagin maximum principle. An analytical solution to the problem was obtained on the base of a differential equation relating the orientation quaternion and angular momentum of a spacecraft.
Key properties of the optimal solution are formulated in analytical form; the features of optimal motion are studied in detail. The control law is formulated in the form of explicit dependence between control and phase variables. In a case when the controlling torque is limited by the given restriction (at the beginning and end of a turn) analytical formulas have been written for the duration of braking and acceleration. Main relations which determine optimal values of parameters of the algorithm for control of angular momentum are given. Examples and results of mathematical modeling of spacecraft motion formed by optimal control were given. This data in addition to the theoretical descriptions illustrates the process of reorientation in evident form and demonstrates the practical feasibility of a designed method for control of angular momentum during spatial turn.
The designed optimal algorithm of control of spacecraft motion improves the efficiency of spacecraft attitude system and originates more economical performance of spacecraft during flight on orbit.
Tailoring Ti3C2Tx MXene Flake Sizes for Modified Electrochemical Performance: A Top-down Approach
Two-dimensional (2D) materials such as MXene (Ti3C2Tx) have garnered extensive attention in recent years due to their exceptional performance across various domains. The flake size of Ti3C2Tx notably influences its specific surface area a pivotal factor in interfacial interactions within electrochemistry.
Presently modifying the flake size of bulk Ti3C2Tx typically involves complex and costly processes like ultrasonic treatment and isolation. Leveraging the specific preparation principle of MXenes which involves etching the A layers in precursor MAX phases a top-down strategy for producing Ti3C2Tx flakes of desired sizes has been proposed in this work. In this approach precursor Ti3AlC2 particles undergo ball-milling to adjust their size.
Through this innovative strategy dispersions of Ti3C2Tx flakes with varying average lateral sizes are generated enabling an investigation into the impact of lateral size on the electrochemical properties of Ti3C2Tx flakes. By controlling the ball milling time for Ti3AlC2 powders the resulting average sizes of Ti3C2Tx (0 2 4) are 6.34 μm 2.16 μm and 0.96 μm respectively. Particularly the Ti3C2Tx (2) electrode composed of 2.16 μm sheets demonstrates remarkable performance metrics. It exhibits a high areal capacitance of 845.0 mF/cm2 at a scan rate of 5 mV/s along with a gravimetric capacitance of 244.0 F/g at a current density of 1 A/g.
This study presents a facile method to enable mass production of Ti3C2Tx with sheets of varying sizes addressing both small and large dimensions.
Optimization of a Validated Liquid Chromatographic Method with Chemometric Approach for Estimation of Eugenol from Seed Powder Extract and Perform Anti-oxidant Activity
Developed and validated a new reverse phase high-performance liquid chromatographic (RP-HPLC) method and it is prompt precise sensitive and robust for the estimation of eugenol in seed powder extract of Myristica fragrans.
The chemometric approach was utilized to obtain a rugged and definitive chromatographic method for the purpose.
Method variables such as acetonitrile (%) and flow rate were investigated for robustness and optimization by using a face-centered cubic design (FCCD). The Design Expert 12.0.1.0 software has been employed for this optimization. Further the effects of factors were monitored on the concentrations of eugenol recovered from seed powder extract. Chromatograms have been developed by using an optimized mobile phase mixture containing methanol-water-acetonitrile (10:40:50 v/v/v) and Symmetry® C18 column (5 μm 3.9 ×150 mm). The mobile phase was derived at a flow rate of 1 mL/min and estimation of eugenol was performed at ʎmax 272 nm.
Validation of the method has been carried out to reveal its selectivity linearity precision accuracy LOD and LOQ. Linear calibration plot for eugenol was held over the concentration across 6.25 and 100 μg/mL (R2 = 0.999). The coefficient of variation was less than 1% and accurate recovery of eugenol was observed between 96.80 and 99.56%. The LOD and LOQ have been established to be 1.97 and 6.25 μg/mL respectively. Intraday and Inter-day coefficients of variation have 1.81-1.91 and 1.92-1.57 respectively. Antioxidant activity (AA) by DPPH assay of seed powder extract in five different solvents was performed and % AA activity was calculated against ascorbic acid.
The validated method has founded to be highly robust and will be applied for the analysis of eugenol's formulation. The highest % AA has reported in hexane solvent.
A Statistical-based Stability-Indicating Assay for the Estimation of Salbutamol and Ketotifen using HPLC and HPTLC Methods
There are very few methods for simultaneously determining a combined dose of SAL and KET.
The current study aims to explore accurate precise simple and cost-effective HPLC and HPTLC techniques for the simultaneous assessment of Salbutamol (SAL) and Ketotifen (KET).
The determination of Salbutamol and Ketotifen was performed by HPLC and HPTLC methods using 280 nm and 258 nm as the determination wavelength respectively. Methanol was used to dissolve the drug for estimation in HPLC using mobile phase methanol: 10mM di-Potassium hydrogen orthophosphate in the ratio of 55:45 v/v of pH 4 at a flow rate of 1mL/min and in chloroform: toluene: methanol (7: 2: 3 v/v/v) for the estimation in HPTLC. Moreover a statistical comparison was made between the results obtained through HPLC and HPTLC of Salbutamol (SAL) and Ketotifen (KET) using the Student’s t-test and F-test.
A linear response was observed in the range of 4-24 µg/mL and 2-12 µg/mL respectively for SAL and KET for HPLC. R2 was found to be 0.9998 and 0.9999 respectively. For HPTLC the linear response was observed in the concentration range of 20-120 ng/ spot and 10 - 60 ng/ spot for SAL and KET respectively. R2 was found to be 0.9988 and 0.9998 respectively. The limit of detection (LOD) for HPLC was estimated as 0.34 µg/ml and 0.10 µg/ml for SAL and KET respectively and for the HPTLC method the LOD was estimated as 4.8 µg/ml and 1.5 µg/ml respectively. Analysing the marketed formulation by using both methods SAL and KET within the range of 100 ± 2% were recovered. The results obtained after the estimation of the Mastifen S tablet by applying both methods were according to nominal content. Degradation studies were performed using both methods. It was found that Salbutamol was unstable in hydrolytic oxidative and thermal degradation whereas stable in photolytic conditions. Ketotifen was found to be stable in thermal and photolytic conditions and unstable in hydrolytic and oxidative conditions.
The proposed stability indicating HPLC and HPTLC methods for SAL and KET was found to be simple accurate and reproducible for quantitative estimation in pharmaceutical dosage form without interference from the excipients or degradation products from the main drug component.
Book Review: Applications of Ion Exchange Materials in Biomedical Industries
The book titled “Applications of Ion Exchange Materials in Biomedical Industries” edited by Inamuddin was published by Springer in 2019. The book has 235 pages and the print version has ISBN 978-3-030-06081-7. The eBook version has ISBN 978-3-030-06082-4 and is available at https://doi.org/10.1007/978-3-030-06082-4. Ion exchange chromatography has become increasingly popular in recent years due to its use in various industries including biotechnology pharmaceuticals agriculture and the environment. The book “Applications of Ion Exchange Materials in Biomedical Industries” edited by Inamuddin and published by Springer in 2019 covers the use of ion exchange materials in biomedical applications. The book outlines the principles of ion exchange chromatography (IEC) a crucial technology used to separate ionic chemicals through ion exclusion and partition. It also covers IEC in separating purifying identifying and extracting substances such as amino acids morphine nucleotides nucleosides sorbitol vitamins purines and pyrimidines. This book review will be useful to researchers industrialists medical professionals and engineers in understanding the concept and applications of ion exchange materials.
Standardization and Evaluation of Triphala Juice and Quantification of Gallic Acid as a Biomarker by Analytical Techniques
Standardization of Triphala Juice was performed by using the WHO Guidelines. The Parameters included Preliminary Analysis Phytochemical Identification Heavy Metal Estimation etc. A new simple specific precise and accurate UV Spectrophotometric High-Performance Liquid.
Chromatography and High-Performance Thin Layer Chromatography method has been developed for the Estimation of Gallic Acid in pure form.
The UV- Spectrophotometric method was developed using Schimadzu 1800 UV - Visible spectrophotometer using methanol as a solvent. The method was shown to be linear with a detection wavelength of 273 nm for Gallic Acid.
The separation was achieved on the Schimadzu Prominence-I RP-HPLC and the column used was C18 column using mobile phase consisting of mixture of Methanol: 0.1% OPA (50:50). The detection was carried out at 280 nm with a flow rate of 0.7 ml/min. The retention time for Gallic Acid was found 3.89 minutes. The calibration curve was found linear (r2 = 0.999) for RP- HPLC method.
The HPTLC method was developed using Aetron Sprayline instrument Methanol as solvent and mobile phase consisting of Toluene: Ethyl Acetate: Formic Acid: Methanol (3:3:0.9:0.2). The method was found linear and the wavelength of detection for Gallic Acid was 254 nm respectively.
The percentage recoveries for both methods were found in the 98.0- 102.0% range.
The methods were validated in accordance with International Conference on harmonization acceptance criteria for specificity linearity precision accuracy robustness and system suitability. The excipients did not interfere in the determination of Gallic acid in Triphala Juice.
The suggested approach was effectively implemented for the quantitative determination of gallic acid in Triphala juice which would aid in quality control.
Atmospheric Flow Fields: Theory, Numerical Methods And Software Tools
This e-book is a collection of chapters on practical and theoretical aspects of atmospheric flows over flat and complex terrain with applications to air pollution and wind energy.
It is divided into two main sections: the first section deals with atmospheric dynamics and the second section explains the planetary boundary-layer parameterization that is a key issue for the definition of initial wind flow fields in meteorological and prognostic estimation of turbulence - "Ensemble Nowcasting" for short term prediction.
The e-book is unique in that it features a combination of theoretical analytical and numerical techniques and tools where the techniques presented in the e-book are demonstrated and can be replicated by the reader. These practical tools can be used to easily test selected mathematical formulation or for performing a swift sensitivity analysis. The tools presented in this reference work focus primarily on mixing height evaluation representative day identification and PBL characterization by elementary measurements evaluated at surface level.
This e-book should be a valuable reference for readers interested in the meteorology of atmospheric wind flows.
Multifunctional Two- and Three-Dimensional Polycrystalline X-Ray Diffractometry
A novel X-ray diffraction (XRD) theory is intensively revealed in this book. The theory will extend present XRD view from one dimension to two and three dimensions enabling readers to see the invisible characteristics inside materials. The two-dimension (2D) theory involves two angular variables of the Bragg angle Θ and the angle α introduced to show the location of sample with respect to incident X-ray beam. Such variables are used to compose a set of general mathematical models which include a general diffraction intensity equation an azimuth-angle equation and a common scan mode as well as the Bragg equation for both of the surface-and transmission-reflection treatments. This book stresses upon the X-ray analyses for natural and synthetic materials. This book is dedicated to create a bridge between basic texts and specialist works and should be helpful to scholars studying XRD theory.