Prominent Peak Research Articles

Spatio-temporal variability of small-scale leads based on helicopter maps of winter sea ice surface temperatures

Observations of sea ice surface temperature provide crucial information for studying Arctic climate, particularly during winter. We examined 1 m resolution surface temperature maps from 35 helicopter flights between October 2, 2019, and April 23, 2020, recorded during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC). The seasonal cycle of the average surface temperature spanned from 265.6 K on October 2, 2019, to 231.8 K on January 28, 2020. The surface temperature was affected by atmospheric changes and varied across scales. Leads in sea ice (cracks of open water) were of particular interest because they allow greater heat exchange between ocean and atmosphere than thick, snow-covered ice. Leads were classified by a temperature threshold. The lead area fraction varied between 0% and 4% with higher variability on the local (5–10 km) than regional scale (20–40 km). On the regional scale, it remained stable at 0–1% until mid-January, increasing afterward to 4%. Variability in the lead area is caused by sea ice dynamics (opening and closing of leads), as well as thermodynamics with ice growth (lead closing). We identified lead orientation distributions, which varied between different flights but mostly showed one prominent orientation peak. The lead width distribution followed a power law with a negative exponent of 2.63, which is in the range of exponents identified in other studies, demonstrating the comparability to other data sets and extending the existing power law relationship to smaller scales down to 3 m. The appearance of many more narrow leads than wide leads is important, as narrow leads are not resolved by current thermal infrared satellite observations. Such small-scale lead statistics are essential for Arctic climate investigations because the ocean–atmosphere heat exchange does not scale linearly with lead width and is larger for narrower leads.

Observation of Multiple Topological edge States in Square-Root electric circuits

Square-root topological states are new topological phases, whose intriguing topological properties are inherited from the parent lattice Hamiltonian. Because of the square-root procedure, the bulk gap of the parent Hamiltonian is doubled. In this letter, we report the observation of the square-root topological insulators (SRTIs) in topological LC circuits, whose squared Hamiltonian includes a Su-Schrieffer-Heeger (SSH) model, a well-known example of topological insulators (TI). The multiple localized edge states falling in different bandgaps are observed with characteristic phase structures, in sharp contrast to the discrete diffraction in a topologically trivial structure. These edge states with zero energy are manifested by a prominent impedance peak at the midgap frequency and directly observed by impedance measurements. Our work opens up an alternative gateway towards actively controllable topological systems and may bring about new possibilities in topology-driven electronic devices.

Separation and Characterization of Nickel Hydroxide from Waste Solution Using Ca(OH)2 Precipitation in Chloride Media

Nickel hydroxide (Ni(OH)2) is a valuable compound derived from nickel, widely utilized across various fields because of its versatile properties. This study aimed to characterize as-prepared β-Ni(OH)2 via chemical precipitation using various analytical techniques. X-ray diffraction (XRD) analysis confirmed the formation of a β-Ni(OH)2 hexagonal crystalline structure, validating the successful precipitation. Fourier-transform infrared spectroscopy (FTIR) spectra exhibited main characteristic peaks of (υOH) and υ(NiO), corresponding to the formation of nickel hydroxide (Ni(OH)2). Subsequently, X-ray photoelectron spectroscopy (XPS) revealed a prominent peak for Ni2+ oxidation, confirming the successful precipitation of nickel hydroxide at pH 6.5, which identifies the existence of impurities, such as chlorine and calcium, from the waste matrix. Scanning electron microscopy (SEM) micrographs demonstrated stratified granules with a nearly pure brucite crystalline phase, typical of β-Ni(OH)2. Furthermore, the surface morphology revealed a coarse texture and uneven clustering, suggesting possible elevated oxide levels on the Ni surface. Energy-dispersive X-ray spectroscopy (EDX) confirmed the presence of nickel (Ni) and oxygen (O), with Ca impurities attributed to the chemical precipitation process. Particle size distribution analysis estimated an average particle size of 2.0 µm. Additionally, the precipitation of nickel was investigated using inductively coupled plasma optical emission spectroscopy (ICP-OES). Ni was observed in decreasing order, 62.7 g/L, 0.8 g/L, and 0.501 g/L in the pregnant leach, precursor solution, and solid precipitate (cake), respectively. The separation of Ni(OH)2 through the precipitation process from the waste (acidic chloride media) enabled efficient recycling and re-use of nickel, which provides a cost-effective and environmentally friendly method for the highly efficient utilization of waste (acidic chloride media).

Utilizing agricultural biowaste for food safety: Integrating naturally synthesized silver nanoparticles as antibacterial coating

The growing global population drives increased food demand, impacting the global packaging materials sector, leading to the development of active packaging to enhance food quality, shelf life, and safety. Proper packaging materials, with improved antibacterial and antioxidant barriers, are becoming important in the food sector to reduce food loss and contamination. This study uses Egyptian basil Ocimum basilicum L manufacturing wastes as a biowaste, an agro-industry waste, as a reducing and capping agent to biosynthesize silver nanoparticles (AgNPs). Then, different contents from AgNPs (0.5, 2, 4 wt%) were entrapped into polyurethane nanofiber (PUNFs) to enhance the antimicrobial and antioxidant properties. Gas chromatography/mass spectrometry (GC/MS) was employed to analyze the chemical constituents present in the aqueous peel extract of Ocimum basilicum L. The physicochemical properties of AgNPs before and after entrapped nanofibers were investigated, their antimicrobial and antioxidant properties were evaluated. As a result of the distinctive surface plasmon resonance properties exhibited by Ag (metallic nanoparticles), there are notable peaks observed at 272.5 nm and a prominent peak at 467.3 nm. TEM analyses indicated that the AgNPs were consistently round and uniform, measuring an average of 17.16 ± 1.94 nm in diameter; SEM also confirmed these findings. AgNPs were found to possess their typical crystalline structure, as evidenced by the results of XRD and TEM analyses. The rise in nanofiber diameter is responsible for the escalated AgNP concentration. The presence of AgNPs and Ocimum basilicum L biowaste significantly enhanced the antibacterial and antioxidant properties compared to pure TPU.

Abstract 5014: Analytical validation of a complete system for detection and characterization of genomic aberrations in circulating tumor DNA

Abstract Cell-free DNA (cfDNA) fragments are readily detected at a low concentration in the human blood stream. In healthy patients cfDNA is primarily derived from apoptosis of hematopoietic cells. In cancer patients circulating DNA derived from tumor cells (ctDNA) undergoing apoptosis, shedding, and necrosis contribute to total cfDNA. Next generation sequencing (NGS) of cfDNA isolated from patient plasma can be used to fully characterize cancer driven changes in the tumor DNA including the relative contribution of cfDNA, single nucleotide variants (SNVs), small insertions and deletions (Indels), larger deletions, regions of amplified DNA, and structural rearrangements. Frontage has developed a complete lab system for analysis of circulating cfDNA including automated sample extraction, preparation and sequencing of libraries targeting exon sequences of 293 oncology-related genes, and a bioinformatic reporting system. The Frontage sample extraction process uses a post-extraction size selection step to remove high molecular weight DNA derived from lysed blood cells in the plasma sample to increase the sensitivity of detection of ctDNA. The NGS platform couples hybridization-based selection of genomic DNA fragments derived from protein-coding exons with deep sequencing to ~4,000X gross coverage on the NextSeq 2000. The bioinformatic pipeline integrates unique molecular barcode-based generation of consensus reads for each template molecule, somatic variant calling with GATK Mutect2 and FreeBayes, and removal of false positive variants by comparison to a 60 samples healthy patient data set. Analytical validation was performed for each component of the system. For verification of the sample extraction process, cfDNA was extracted in duplicate from four lots of pooled K2 EDTA plasma of healthy patients as well as individual K2 EDTA plasma of colorectal cancer (CRC) patients in four independent extraction runs. The mean yields of cfDNA from healthy samples ranged from 2.3 - 4.2 nanograms per ml plasma and all 32 of the isolated cfDNA aliquots from healthy patient plasma showed a prominent peak around 167 nt with minimal contamination from high molecular weight DNA. For validation of the NGS and bioinformatics platform a set of 8 different reference cfDNAs were processed through four independent runs of library preparation, sequencing, and analysis. For each of the validation runs, greater than 97% of 208 SNVs and Indels with expected allele frequencies (AF) between 2-3% were detected by the platform with higher levels of accuracy for variants at above 3% AF. Two or less false positive variants per run were detected out of 278,000 nucleotides of verified non-mutated sequence that overlapped with the 293 gene panel. Four known DNA amplification events were detected in each of the validation runs. Data from characterization of CRC and other clinical samples with the system will be presented. Citation Format: Ericca Stamper, Weiming Shen, Aman Pruthi, Casey Nagel, Marcin Piechota, Katarzyna Tomala, Qi Wei, David Willoughby. Analytical validation of a complete system for detection and characterization of genomic aberrations in circulating tumor DNA [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5014.

Characterization and function of particulate organic matter: Evidence from lakes undergoing ecological restoration

Particulate organic matter (POM) plays a crucial role in the organic composition of lakes; however, its characteristics remain poorly understood. This study aimed to characterize the structure and composition of POM in Lake Baiyangdian using many kinds of techniques and investigate the effects of different extracted forms of POM on water quality. The suspended particulate matter in the lake had complex compositions, with its components primarily derived from aquatic plants and their detritus. The organic matter content of the suspended particulate matter was relatively high (organic carbon content 27.29–145.94 g/kg) for the sum of three extractable states (water-extracted organic matter [WEOM], humic acid, and fulvic acid) and one stable bound state (humin). Spatial distribution analysis revealed that the POM content in the water increased from west to east, which was consistent with the water flow pattern influenced by the Baiyangdian water diversion project. Fluorescence spectroscopy analysis of the WEOM showed three prominent peaks with excitation/emission wavelengths similar to those of dissolved organic matter peaks. These peaks were potentially initial products of POM conversion into dissolved organic matter. Furthermore, the intensity of the WEOM fluorescence peak (total fluorescence peak intensity) was negatively correlated with the inorganic nitrogen concentration in water (p < 0.01), while the intensity of the HA fluorescence peak showed a positive correlation with the inorganic nitrogen concentration (p < 0.01). This suggested that exogenous organic matter inputs led to the diffusion of alkaline dissolved nitrogen from sediment into water, while degradation processes of aquatic plant debris contributed to the decrease in inorganic nitrogen concentrations in the water column. These findings enhance our understanding of POM characteristics in shallow lakes and the role of POM in shallow lake ecosystems.

Characterization of Green and Chemically Synthesized Yttrium Oxide Nanoparticles from Tribulus Terrestris

Nanotechnology has a significant impact on different fields such as medicine, information technology, energy, advanced materials, textiles, and many other new areas. In this study, the characterization of the green synthesized and chemically synthesized nanoparticle from Tribulis terrestris was studied. Yttrium nitrate hexahydrate was employed as a precursor material for the synthesis of nanoparticles. Characterization study was performed by using UV–Vis spectroscopy, FTIR, FE-SEM. For green synthesis, the peak was observed at 311[Formula: see text]nm while for chemically synthesized nanoparticles the maximum peak absorption was seen at 239[Formula: see text]nm. The FTIR analysis for green synthesized nanoparticles reveals the presence of three prominent peaks due to C–O stretching vibration, C–O bending vibration and Y–O vibration. Chemically synthesized nanoparticles show the presence of C–O stretching vibration, C–O bending vibration and OH-stretching. The results of SEM studies indicated the particle shape and size of chemically synthesized nanoparticles and green synthesized nanoparticles. Green synthesized Y2O3 NPs are an appropriate option for use in medicinal applications. Furthermore, detailed in vivo studies are needed to determine the safety and effectiveness of these green synthesized Y2O3 nanoparticles.

Miniaturized Optical Glucose Sensor Using 1600–1700 nm Near‐Infrared Light

AbstractBlood glucose measurement is crucial for diabetes diagnosis and treatment, but invasive sampling methods have drawbacks. Non‐invasive near‐infrared (NIR) spectroscopy‐based optical glucose sensing has gained attention but faces challenges due to the strong absorbance of NIR light by water and the need for complex equipment. Here, four distinct glucose fingerprints at specific NIR wavelengths: 1605, 1706, 2145, and 2275 nm are identified. Utilizing a surface‐mounted LED with a spectral range of 1600–1700 nm and focusing on the most prominent peaks at 1605 and 1706 nm, a miniaturized and non‐invasive glucose sensor is developed. The device successfully detects in vitro assays of glucose solutions within the physiological range of 50–400 mg dL−1, attaining a limit of detection as low as 10 mg dL−1. The findings demonstrate the feasibility of NIR spectroscopy‐based glucose sensing and its potential applications in non‐invasive point‐of‐care diagnostics, with the potential for extension to other biomarkers in future.

Investigations of swift heavy ion induced thermoluminescence effect, trapping parameter analysis, and density functional theory of MgB4O7: Eu phosphor

The present work reports swift heavy ion (SHI) induced thermoluminescence (TL) dosimetric properties and density functional theory (DFT) studies of Eu doped MgB4O7 phosphor. Comparative investigations of structural, and luminescent properties of MgB4O7:Eu phosphor upon irradiation by 100 MeV Ag7+ and Ni7+ ion beams at the varied fluence range from 1 × 1010 ion/cm2 to 5 × 1012 ion/cm2 are presented systematically. Eu doped MgB4O7 phosphor is prepared by facile hydrothermal method. X-ray diffraction pattern of the material reveals its orthorhombic structure with crystallite size of ∼30 nm. Fourier transform infrared spectroscopy (FTIR) studies demonstrate loss of crystallinity of material after the SHI irradiations. Correlation of stopping powers and projectile range calculations is performed using SRIM software. The investigated photoluminescence properties show emission bands located in the orange-red region with prominent peaks centered at ∼593 nm and ∼625 nm corresponding to 5D0→7F1 and 5D0→7F2 transitions of Eu3+ion. The influence of ion beam fluence on the photoluminescence properties has been explored. Variation in the intensity of the PL peaks without any shift in the peak positions is observed at different ion fluence. The TL glow curve of phosphor exhibits two major dosimetric peaks (a) at 185 °C and 275 °C and (b) at 172 °C and 273 °C upon Ag7+ and Ni7+ ion beam irradiation respectively. The phosphor shows fairly good linear dose response in the range of 1 × 1010 ion/cm2 to 5 × 1012 ion/cm2. Fading measurements reveal 10% and 12% fading for the irradiation of Ag7+ and Ni7+ ions respectively in two months. Trapping parameter calculations of SHI irradiated phosphors are carried out via various TL glow curve analysis methods such as, peak shape method, whole glow peak method, and glow curve deconvolution method. Efficient thermoluminescence properties of MgB4O7:Eu make it a potential phosphor material and promise to provide avenue into swift heavy ion dosimetry applications. DFT computational studies performed to obtain the electronic structure of Eu doped MgB4O7 phosphor support the experimental results of crystal structure, symmetry and electronic structure studies.

Thermoluminescence characteristics of gamma-irradiated nano-alumina

The focus of this study lies in exploring the properties of thermoluminescence (TL) in nano-alumina, including the correlation between TL intensity and absorbed dose, identification of individual luminescence peaks, and investigation of trap parameters for potential dosimetry applications. The samples were irradiated by 60Co with doses ranging from 530 to 2646 Gy. Micro-sized α-Al2O3 had a prominent dosimetry peak at maximum temperature Tm = 435 K. Nano-α-Al2O3 samples with 40 and 50 nm particle sizes exhibited a TL luminescence glow curve, with the main dosimetry peak in the low-temperature region and a complex structure at higher temperatures (above 500 K). The observed maximum of the main dosimetry peak depended on the nanoparticle size and was 460 K for the sample with particle size of 40 nm and 467 K for 50 nm. The main dosimetry peak was described by the superposition of the two peaks.A computerized glow curve deconvolution method was applied to determine the parameters of the traps responsible for TL using the Microsoft Windows-operated GlowFit program, assuming first-order kinetics. The found values of the activation energies were 0.97 ± 0.01 eV for the trapping center responsible for the peak with Tm = 458 ± 3 K and, accordingly, 1.05 eV for the peak with Tm = 473 ± 3 K. The estimated values of the frequency factor were s ≈ 1.01 × 1010 and 1.3 × 1010 s−1 for the peak with Tm = 458 ± 3 K, and 2.06 × 1011 s−1 for the peak with Tm = 473 ± 3K, respectively. The lifetime for the traps in nano-α-Al2O3 was estimated as 43–56 days for the first trap and approximately 65 days for the second trap. It is assumed that these traps are responsible for TL emission at the low-temperature part of the glow curve.

Mesoporous Ag@WO3 core–shell, an investigation at different concentrated environment employing laser ablation in liquid

In this study, silver-tungsten oxide core–shell nanoparticles (Ag–WO3 NPs) were synthesized by pulsed laser ablation in liquid employing a (1.06 µm) Q-switched Nd:YAG laser, at different Ag colloidal concentration environment (different core concentration). The produced Ag–WO3 core–shell NPs were subjected to characterization using UV–visible spectrophotometry, X-ray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive spectroscopy, electrical analysis, and photoluminescence PL. The UV–visible spectra exhibited distinct absorption peaks at around 200 and 405 nm, which attributed to the occurrence of surface Plasmon resonance of Ag NPs and WO3 NPs, respectively. The absorbance values of the Ag–WO3 core–shell NPs increased as the core concentrations rose, while the band gap decreased by 2.73–2.5 eV, The (PL) results exhibited prominent peaks with a central wavelength of 456, 458, 458, 464, and 466 nm. Additionally, the PL intensity of the Ag–WO3-NP samples increased proportionally with the concentration of the core. Furthermore, the redshift seen at the peak of the PL emission band may be attributed to the quantum confinement effect. EDX analysis can verify the creation process of the Ag–WO3 core–shell nanostructure. XRD analysis confirms the presence of Ag and WO3 (NPs). The TEM images provided a good visualization of the core-spherical shell structure of the Ag–WO3 core–shell NPs. The average size of the particles ranged from 30.5 to 89 (nm). The electrical characteristics showed an increase in electrical conductivity from (5.89 × 10−4) (Ω cm)−1 to (9.91 × 10−4) (Ω cm)−1, with a drop in average activation energy values of (0.155 eV) and (0.084 eV) at a concentration of 1.6 μg/mL of silver.

Synthesis and Thermoluminescence Properties of Undoped Calcium Fluoride (CaF2) Nanoparticles using Co-Precipitation Method

This study investigated the thermoluminescence properties of undoped CaF2 nanoparticles synthesized via co-precipitation with ethanol. X-ray diffraction revealed pure CaF2 nanoparticles with a complete cubic structure and an average crystallite size of 36.5 nm. Scanning electron microscopy confirmed the nanoscale size, averaging 51.23 nm. Electron dispersive spectroscopy analysis showed that the sample mainly consists of Ca and F, with oxygen potentially introducing defects in the crystal structure. Synthesized nanoparticles TL glow curves exposed to 7 mGy of 90Sr beta rays exhibited a prominent peak at 205 oC in thermoluminescence glow curves, likely due to oxygen-induced defects that act as thermoluminescence activators. The thermoluminescence activating energy and the frequency factor of the CaF2 nanoparticles were determined using initial rise methods of approximately 0.83 eV and 5.99 x 10-19, respectively.

Standardization of Gandhaga Thailam: A Traditional Siddha Formulation for Skin Disorders

Standardization is a part of Drug development process. Identifying the quality of a Siddha formulation is essential before it taken up for In vivo, In vitro studies and Clinical trials. Gandhaga thailam a Mineral based Siddha medicine to treat various ailments like Eczema, Ulcer, Peptic ulcer diseases etc. Test samples were extracted with acetone and briefly homogenized. Further filtration followed by addition of acetone to the test mixture. The test samples were heated using a rotary evaporator at a temperature not exceeding 40°C until almost complete evaporation of the solvent. HPTLC analysis reveals the presence of thirteen prominent peaks corresponds to the presence of thirteen versatile phytocomponents present within it. Rf value of the peaks ranges from 0.02 to 0.80. Study indicates that the Gandhaga Thailam is in standard quality, hence the preparation and purification processes of ingredients were done as per the literature. With these results Gandhaga thailam may be subjected to invitro and invivo toxicity studies in future. Results reveal the quality of the Medicine Gandhaga Thailam and may be the fingerprint for the future analysis on Gandhaga Thailam.

Effects of the Northern Hemisphere sudden stratospheric warmings on the Sporadic-E layers in the Brazilian sector

Tidal and Planetary Wave (PWs) amplitudes are strongly influenced by Sudden Stratospheric Warming (SSW) events. A nonlinear interaction between the tidal winds and planetary waves during the SSW may contribute to the intensification of sporadic-E (Es) layers in the lower thermosphere. This work investigated the relationship between SSW events in the Northern Hemisphere and the Es layer occurrence at low latitudes in the Brazilian sector. We used data from digital ionosondes installed in the observatories of Araguatins (ARA, 5.65° S; 48.12° W; dip lat. −5.44°) and São José dos Campos (SJC, 23.18° S; 45.89° W; dip lat. −21.37°) to analyze the Es layers. Additionally, we used the temperature, zonal wind, and PWs data at high latitudes in the Northern Hemisphere during the major SSW event that occurred in February/2018 and during the events of Dec/2018–Jan/2019 and Dec/2020–Jan/2021. The results showed a maximum frequency peak of 20 MHz (∼5 × 106 electrons.cm−3) at ARA and SJC during these SSW events. The large values of ftEs, fbEs, and electronic densities were observed between 100 and 115 km height in the Esf/l type layers during daytime or nighttime periods. The results also showed that the number of large values of ftEs, fbEs, and electronic density of the Es layer was much higher in ARA than in SJC, in general. The wavelet power spectrum analyses of the ftEs and fbEs showed a periodicity of 2-days before and after the central day of the SSWs events at the station of ARA, with three prominent peaks in the 2018/2019 event. At the SJC station the quasi-2-day periodicity in the wavelet analyses of the ftEs was observed after the central day in all three SSW events, with a peak before the central day during the 2020/2021 event.

Preparation and Study the Properties of PVDF/PEO/WO2 Hybrid Nanocomposite Thin Films Prepared by a Spin Coating Method

In this work, using the spin coating method to create polyvinylidene fluoride (PVDF)/polyethylene oxide (PEO) thin films, the effects of nano-tungsten oxide (WO2) doping were investigated. The novelty of this research lies in its investigation of varying weight concentrations of WO2 nanoparticles (NPs) within the composite films. Comprehensive characterization techniques were employed, including structural analysis via X-ray diffraction (XRD), which revealed a clear and prominent peak in the XRD of the PVDF/PEO films, and the films' polycrystalline nature with tetragonal structures. The grain size was noted to increase with higher WO2 NPs doping. Field emission scanning electron microscopy (FE-SEM) showed hexagonal-like α-phase PVDF crystals and uniform distribution of WO2 NPs. Furthermore, Fourier-transform infrared spectroscopy (FTIR) confirmed the characteristics of PVDF/PEO and identified specific doping compounds, confirming successful incorporation. The optical transmittance spectra unveiled the films' optical band gap energy, optical transition types, and absorption characteristics, where novelty emerged as the band gap energy significantly increased from 3.0 eV to 3.64 eV with an increased WO2 NPs weight doping percentage, signifying profound electronic structure modifications and potential applications in optoelectronics and sensors.

Comprehensive Characterization of Starch from Diverse Sources: Physicochemical, and Functional Properties

AbstractThe present study is based on the comprehensive characterization of starches from pearl millet, sorghum, mango kernel, and water chestnut. The starches are analyzed to observe the difference in physicochemical, pasting, rheological, Fourier transform infrared spectroscopy (FTIR), and X‐ray diffraction (XRD) properties. The amylose content from diverse sources ranges from 17.3 to 26.3%. The swelling power and solubility of the starches are influenced by the increase in temperature. It is observed that an increase in temperature results in increased swelling power and solubility. At 90 °C, mango kernel starch shows the highest swelling power while pearl millet starch shows the lowest. The botanical sources influence the pasting and rheological properties, and a significant difference (p &lt; 0.05) is observed in all the parameters recorded. The peak viscosity (PV) of starches ranges from 1256 to 2101 cP. All the starches possess almost similar and typical starch FTIR spectra. The starches from all sources show prominent peaks at 15.2, 17, 18.3, and 23 (2θ), corresponding to a typical A‐type starch crystallinity organization.

Synthesis, Structural Characterization and Photophysical Properties of Bis(4′-chloro-2,2′:6′,2″-terpyridyl)nickel(II)chloride Dihydrate

Nickel(II) complex viz. bis(4′-chloro-2,2′:6′,2″-terpyridyl)nickel(II)chloride dihydrate, [Ni(Cltpy)2]Cl2·2H2O where Cltpy is a tridentate ligand was synthesized under mild conditions by conventional method. The octahedral geometry of nickel(II) complex was revealed by single crystal X-ray diffraction (SCXRD) studies. The synthesized Ni(II) complex was characterized by Fourier transform-infrared (FT-IR), elemental analysis, scanning electron microscope (SEM), thermal analysis (TG-DTA), photoluminescence (PL) and diffuse reflectance (DR) spectra. A prominent peak at 630 nm was recorded in the DR spectrum and the band gap energy of 2.38 eV was resulted in accordance with Kubelka-Munk (K-M) theory. The photoluminescent spectra of the synthesized nickel(II) complex displayed the emission of blue green light. The commission internationale de l’eclairage (CIE) coordinates (0.2641, 0.3722) were obtained from its CIE graph.

Radial Distribution of Electron Quasi-thermal Noise in the Outer Heliosphere

Voyager 1 and 2 are only the two spacecraft that have arrived and passed through the heliospheric boundaries. Based on the plasma data from the Voyager 2 spacecraft, the electron quasi-thermal noise (QTN) is investigated by using of the electron population model consisting of a core with Maxwellian distribution and a halo with kappa distribution. The power spectra of the electron QTN is calculated at different heliocentric distances from 1 to 110 au. The parametric dependence of the QTN power spectra and the effective Debye length on the model parameters, such as the density ratio and temperature ratio of the halo to the core, kappa index and the antenna length, are discussed further. The results show that the electron QTN spectrum consists of a plateau in the low frequency band f < f pt , a prominent peak at the plasma frequency f pt , and a rapid decreasing part in the high frequency band f > f pt . The QTN plateau level basically falls down outwards until the termination shock crossing at about 84 au, after which the plateau rebounds a little near the heliopause. Although the model parameters can be very variable, the QTN plateau level does not present more than the double change in a fairly wide range of the model parameters. The presented results can be useful for future deep-space explorations in the heliosphere and can provide valuable references for the design of onboard detectors.

Physicochemical characterization, Phytochemical analysis and Anti-microbial activity of Elathy mathirai

Elathy Mathirai is a Siddha herbomineral formulation indicated to cure sori(itching), sirangu(Scabies), suram(fever), vaayu, maandham(gastro intestinal disorder) . The aim of the study is to standardize Elathy Mathirai to ensure its quality, purity and safety through its physicochemical, chromatographic, phytochemical, heavy metal, pesticide residue and aflatoxins analysis and the secondary objective is to evaluate its antimicrobial property. This study determines the physicochemical paramaters that are loss on drying, total ash, acid insoluble ash, water soluble extractive, alcohol soluble extractive and pH as 5.667% , 5%, 0.014 %, 14.93 %, 8.3% and 5.6 respectively denotes purity and quality of the drug. From the study results it is ensured that the test drug Elathy mathirai is free from pesticide toxicity and aflatoxins. Qualitative preliminary phytochemical analysis shows the presence of alkaloids, Flavanoids,steroids, triterpenoids, saponins, coumarins, phenol, tannin, sugar and betacyanin. HPTLC finger printing analysis reveals the presence of seven prominent peaks Rf value ranges from 0.04 to 0.39 corresponds to the presence of seven components present within it. It was observed from the results of In vitro anti microbial assay that the formulation EM reveals significant level of activity against bacteria Klebsiella pneumonia and observed moderate activity against Staphylococcal aureus, Pseudomonas aeruginosa and posess consistent anti fungal activity against Candida albicans and there is no significant effect on Aspergillus niger. The obtained results shows that the EM complies with the regulatory standard and also possess significant anti microbial property against the tested microbes.

Multitasking needle-shaped copper oxide nanorods decorated cystine modified polymer/graphene oxide nanocomposite for 4-nitrophenol reduction, dye degradation, and textile effluent treatment

Nitroaromatic chemicals, including 4-nitrophenol (4-NP) and dyes, pose substantial risks to human health and the environment. Various catalysts that facilitate the reduction of 4-NP to 4-aminophenol (4-AP) have been documented to reduce its toxicity. Herein, we developed a novel nanocomposite consisting of needle-like copper oxide nanorods immobilized with L-cystine functionalized polyglycidyl methacrylate integrated graphene oxide (Cys-PGMA@GO-CuO) nanocomposite. The formation of this nanocomposite was comprehensively characterized using various analytical techniques. X-ray diffraction revealed a semi-crystalline nature for pure PGMA/GO with a prominent peak at 2θ = 19.25°. The introduction of inherently crystalline CuO nanoparticles in Cys-PGMA@GO-CuO rendered the entire composite completely crystalline. Further, the photocatalytic efficiency of the Cys-PGMA@GO-CuO nanocomposite was evaluated through advanced oxidation processes (AOP) for treating various toxic pollutants in wastewater remediation. The nanocomposite efficiently degraded dyes like methyl orange (99.8%) and methylene blue (99.9%) in just 50 mins and reduced toxic 4-NP to 4-AP within 40 mins. We further investigated the optimal degradation conditions based on [oxidant], [dye], and the presence of scavengers to understand the rate of degradation. Notably, the composite exhibited remarkable recyclability and stability. The performance of Cys-PGMA@GO-CuO was further evaluated using real wastewater samples, achieving a remarkable decolorization of 99.5% in textile dyeing wastewater and 97.1% in methylene blue-contaminated tap water. These results demonstrate the promising potential of this nanocomposite as an economically viable alternative approach for removing various organic pollutants from wastewater. Additionally, its successful application in real water sample analysis suggests its significant potential for practical implementation in water treatment processes.