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Three gold(III) nanostructured complexes of nicotinamide (nta), picolinic acid (pica), and isonicotinic acid (inta) were synthesized by the reacted of AuCl3 salt with nta, pica, and inta with 1:2 stoichiometry in the alcoholic medium. The solid products obtained were formulated by comparing experimental and calculated data for microanalytical (C, H, N) and metal. Both produce 1:2 compounds with metal ions. The prepared complexes were characterized by different physico-spectroscopic techniques. The FTIR, and 1H NMR spectral analysis, morphological analysis (scanning electron microscopy SEM, transmittance TEM, and X-ray powder diffraction XRD) of these complexes have been discussed. The conductive behavior of the complexes indicates that all of them behave as electrolytic behavior. The mononuclear gold(III) complexes have formulated as [Au(nta)2(Cl)2].Cl, [Au(pica)2].Cl and [Au(inta)2].Cl. The shifts of the ν(N-H) amino, ν(C=N) pyridine, and ν(C=O) carboxylic stretches have been monitored to find out the donor sites of the ligands. According to the experimental data, the three complexes can be characterized in the solid state as mononuclear, with a four-coordinate stereochemistry. [ABSTRACT FROM AUTHOR]

Nano‐sized tridentate transition metal(II) chelates, specifically [M(FONS)Cl] with H‐FONS = ligand and M = Cu(II) (C1), Ni(II) (C2), Pd(II) (C3), and Pt(II) (C4), underwent synthesis and subsequent characterization. The HOMO–LUMO energy gaps (ΔE) were used to create theoretical models for the structure and confirmation barriers in molecular systems for the ligand (H‐FONS) and metal chelates. It was found that the Cu(II), Ni(II), Pd(II), and Pt(II) chelates have lower values for HOMO–LUMO energy gaps (ΔE), indicating that they are more stable than the H‐FONS 1igand.The metal formed four coordinated with the tridentate NOS donor Schiff base to form square‐planar geometry chelates. The results of TEM, EDX, AFM, and x‐ray diffraction calculations for the bivalent metal chelates indicated sharp and intense diffraction peaks, confirming their crystalline nature and nanoscale particle size. The interaction between calf thymus DNA (CT‐DNA) and the chelates was examined utilizing the UV–Vis spectroscopic method, revealing their capacity to bind with CT‐DNA via intercalation mode. Nano‐sized metal(II) chelates show a higher viscous nature than H‐FONS. The cytotoxicity of H‐FONS and its metal(II) chelates in nano form against the liver cancer cell line (HepG2) was evaluated by studying in vitro cell proliferation using the MTT assay. The findings demonstrated that all compounds exhibited anticancer properties, displaying a dose‐dependent response. Our flow cytometry data indicate significant levels of cell cycle arrest in the liver cancer cell line. By molecular docking study, it was found that the Cu(II) chelate (C1) showed the highest and better binding affinity (−8.2 and −8.7 kcal/mol) than other 1igand (H‐FONS) and comp1exes (C2–C4) for the BCL2 and PBP3 proteins central activities. [ABSTRACT FROM AUTHOR]

New remains of a Taymyr mammoth, including bones, bone collagen, hairs, skin, and soft (muscle and fat) tissues were studied comprehensively by mineralogical, spectroscopic, chromatographic, and isotope-geochemical methods. The results were used to infer the mammoth's biological age and diet, paleoclimatic conditions, and the mechanisms and degree of fossilization of the remains. [ABSTRACT FROM AUTHOR]

Molecular interactions and controlled expression of enzymatic activities are fundamental to all cellular functions in an organism. The active polyphenol in turmeric known as curcumin (CCM) is known to exhibit diverse pharmacological activities. Ribonucleases (RNases) are the hydrolytic enzymes that plays important role in ribonucleic acid (RNA) metabolism. Uncontrolled and unwanted cleavage of RNA by RNases may be the cause of cell death leading to disease states. The protein ribonuclease A (RNase A) in the superfamily of RNases cleaves the RNA besides its role in different diseases like autoimmune diseases, and pancreatic disorders. Interaction of CCM with RNase A have been reported along with the possible role of CCM to inhibit the RNase A enzymatic activity. The interaction strength was found to be 104 M−1 order from spectroscopic results. Quenching of RNase A fluorescence by CCM was 104 M−1 order. Non-radiative energy transfer from RNase A (donor) to CCM (acceptor) suggested a distance of 2.42 nm between the donor–acceptor pair. Circular dichroism studies revealed no structural changes in RNase A after binding. Binding-induced conformational variation in protein was observed from synchronous fluorescence studies. Agarose gel electrophoresis revealed a partial inhibition of the RNase A activity by CCM though not significant. Molecular docking and molecular dynamics studies suggested the residues of RNase A involved in the interaction with supporting the experimental finding for the partial inhibition of the enzyme activity. This study may help in designing new CCM analogues or related structures to understand their differential inhibition of the RNase A activity. [ABSTRACT FROM AUTHOR]

Background: This study was conducted to assess the usefulness of diffusion weighted imaging and magnetic resonance spectroscopy in diagnosing intracranial peripherally enhancing lesions. Methods: This was a hospital-based observational prospective study conducted among 68 patients with the diagnosis of cerebral ring enhancing lesions at the Department of Radiodiagnosis at Shri B.M. Patil Medical College, Hospital and Research Centre, BLDE (DU), situated at Vijayapura, Karnataka, from September 2022 to April 2024, after obtaining clearance from the institutional ethics committee and written informed consent from the study participants. Results: In the distribution of patients showing different metabolites on MR spectroscopy in various ring enhancing lesions of the brain, NAA was decreased in 50% of patients with metastasis, neurocysticercosis, in 71% of patients with primary brain tumors, and in 52.6% of patients with tuberculoma, and increased in 50% of patients with cerebral abscess. There was a significant difference in NAA change with respect to diagnosis. Cho was increased in 50% of patients with cerebral abscess and metastasis, in 100% of patients with neurocysticercosis and primary brain tumors, and in 78.9% of patients with tuberculomas. There was a significant difference in Cho with respect to the diagnosis. Similarly, Lip-Lac was increased in 100% of patients with cerebral abscess and tuberculoma, 30% of patients with metastasis and primary brain tumors, and 50% of patients with neurocysticercosis. There was a significant difference in lip-lac change with respect to diagnosis. Creatine was decreased in 12.9% of subjects with primary brain tumors and 10.5% of patients with tuberculoma. There was a significant difference in creatine change with respect to diagnosis. Metabolite ratios in various intracranial ring-enhancing lesions: the mean Cho/Cr ratio was high in primary brain tumors [4.3 ± 0.36], followed by metastasis and tuberculoma. The mean Cho/NAA ratio was high in primary brain tumors [1.7 ± 1.3], followed by tuberculoma and metastasis. The mean NAA/Cho ratio was high in cerebral abscess [1.65± 0.06] and low in primary tumors. The mean NAA/Cr ratio was high in cerebral abscess [2.2± 0.06], followed by metastasis. There was a significant difference in the mean Cho/Cr, Cho/NAA ratio, NAA/Cho, and NAA/Cr with respect to diagnosis. Conclusion: MRS is not the only criteria for diagnosing ring enhancing lesions. The combination of MRS and diffusion weighted imaging has yielded synergetic potency in detecting various ring-enhancing lesions, leading to accurate diagnosis and thus helping in management and prognosis. [ABSTRACT FROM AUTHOR]

This review concerns the growth process, characterization methods, and potential applications of amino acid and chloride derivatives. Derivatives of amino acids are an ideal option for nonlinear device use. Single-crystal, powder-X-ray diffraction, and high resolution-X-ray diffraction (HRXRD) analyses evaluated the crystal structure and crystalline perfection. Most of the chlorides of amino acid compounds were solidified into monoclinic and orthorhombic crystal structures. The FT-IR and NMR methods were deployed to identify the reported compounds' functional groups and molecular identities. The UV and photoluminescence investigations were performed to investigate the optical characteristics of the reported compounds. Bis-glycine hydrogen chloride showed higher second harmonic generation (SHG) abilities. Laser damage threshold (LDT) and Z-scan analyses are briefly discussed. Dielectric spectroscopy was applied to study the dielectric features related to the applied frequency. Thermal investigations revealed that most crystals exhibited significant thermal stability, making them appropriate for device usage. [ABSTRACT FROM AUTHOR]

Stingless bee honeys are appreciated in the world market due to their nutritional and biological properties. In Argentina, the most commercially exploited species of stingless bee is Tetragonisca fiebrigi whose honey is the only one of its kind incorporated into the Argentine Food Code. The value of stingless bee honeys has been increasing in recent years, making them more prone to adulteration. However, there are no methodologies available to perform adequate controls to verify their authenticity. Therefore, the objective of this work was to develop and validate a UV–Vis spectroscopy and chemometric combined methodology to detect and quantify adulterations of Tetragonisca fiebrigi honeys produced in Argentina. The adulterants analyzed included Apis mellifera honey, three commercial sugar syrups (glucose, extra glucose, maltodex40) and three laboratory-formulated sugar syrups (sucrose, fructose and high fructose). The results showed that through principal component analysis it is possible to differentiate pure honey from adulterated honey. Through linear discriminant analysis and partial least squares regression, unknown mixtures could be classified by determining the degree of adulteration and identifying the type of adulterant used. The method allows detecting the addition of up to 64% of Apis mellifera honey, while the maximum amount of detectable added syrup varies between 51 and 70%, depending on the type of syrup. Highlights: The adulteration of stingless bees honeys has increased due to its economic value. The Argentine Food Code does not define methodology for detection. In Argentina, Tetragonisca fiebrigi is the most widespread species of stingless bee. A method was developed to detect and quantify adulterations. The results demonstrate the effectiveness of the method to determine adulteration. [ABSTRACT FROM AUTHOR]

Stellar activity cycles on magnetically active stars can be estimated by molecular absorption bands. We have previously introduced a molecular index which compares absorptional line strength of the T i O λ 567 n m with its nearby continuum has previously been introduced. In this work we use this indicator to evaluation long-term activity variations for Proxima Centauri star, using spectroscopic data from HARPS. The results indicate periodicity with an activity period of 2873 − 53.9 + 47.4 days, which is similar to the previous measurements from other indicators. [ABSTRACT FROM AUTHOR]

For the determination of tin(II) traces, an extractive spectrophotometric approach is devised. The applied method serves a powerful tool for determination of tin(II), involves the formation of yellow colored complex after the binding of 6-bromo-3-hydroxy-2-(5-methylfuran-2-yl)-4H-chromen-4-one (BHMF) and tin(II) in 1:2 stiochiometry in a slightly acidic medium (HCl). The complex shows absorbance at 434 nm with respect of the blank reagent. The outcomes of spectral investigation for complexation showed a Beer's range of 0–1.3 μg Sn mL−1, molar absorptivity, specific absorptivity and Sandell's complex sensitivity are 9.291 × 104 L mol−1 cm−1, 0.490 mL g−1 cm−1 and 0.002040 μg cm−2 at 434 nm that was stable for two days. The interferences study results showed that this method is free from interferences, when tested with metal ions including Ag, Be, Bi, Ca, Cd, Ce, Co, Hg, Mo, Re, Pt, Se,Ti, U, V, W and other common cations, anions, and complexing agents. The applied method is quite simple, highly selective, and sensitive with good re-producibility. This method has been satisfactorily by utilizing the proposed procedure, and its applicability has been tested by analyzing synthetic samples and an alloy sample of gunmetal. The procedure assumes this because of the scarcity of better methods for determining tin(II). The results are in good agreement with the certified value. [ABSTRACT FROM AUTHOR]

This article presents research work on a spectroscopic survey telescope. Our idea is as follows: for such a telescope, a pure reflecting optical system is designed, which should have an aperture and a field of view (FOV) both as large as possible and excellent image quality, and then a strip lensm (lens-prism) atmospheric dispersion corrector (S-ADC) is added, only for correcting the atmospheric dispersion. Given the fund limitation and the simplicity of scaling up, some 12-m telescopes are designed as examples. Su, Korsch, and Meinel put forward the four-mirror Nasmyth systems I and II, which are used in this paper. FOVs of 1.5°, 2°, and 2.5° are selected. For all systems, the image qualities are excellent. Because the S-ADC relaxes the optical glass size restriction, this 12-m telescope with a FOV of 2.5° can be magnified in proportion to a 16-m telescope. Its etendue (from French étendue) and focal surface will now be the largest in the world. In such a telescope, a pure reflecting optical system can also be obtained. A subsequent coudé system is designed with excellent image quality. [ABSTRACT FROM AUTHOR]

RW Aurigae is a young stellar system containing a classical T Tauri star as the primary component. It shows deep, irregular dimmings, first detected in 2010. At the University Observatory Jena, we carried out optical follow‐up observations. We performed multiband (BVRI) photometry of the system with the Cassegrain‐Teleskop‐Kamera II and the Schmidt‐Teleskop‐Kamera between September 2016 and April 2019, as well as spectroscopy, using the Fibre Linked ÉCHelle Astronomical Spectrograph between September 2016 and April 2018. We present the apparent photometry of RW Aur, which is consistent with and complementary to photometric data from the American Association of Variable Star Observers. The V‐band magnitude of RW Aur changed by up to three magnitudes during the timespan of our monitoring campaign. For the observing epochs 2016/2017 and 2017/2018 we report a decreasing brightness, while in the epoch 2018/2019 the system remained in a relatively constant bright state. In the color‐magnitude diagram, we see that RW Aur lies close to a track for grey extinction. The spectra show a decreasing equivalent width (EW) of the Hα$$ \mathrm{H}\alpha $$ emission line for decreasing brightness, whereas the EW of the [OI]$$ \left[\mathrm{O}I\right] $$ line increases, indicating an increased outflow activity during the obscuration. Both give further evidence for the favored theory that the obscurations are caused by a hot dusty wind emerging from the inner disk. [ABSTRACT FROM AUTHOR]

The Chang'E‐5 (CE‐5) lunar mineralogical spectrometer (LMS) obtained an in situ multiangular spectral data set, with which this work aims to study the photometric properties of the lunar surface in the CE‐5 sampling area. We first converted the LMS Level 2B radiance data to reflectance, and then spliced it and processed thermal correction. We also used a millimeter‐scale digital elevation model (DEM) to re‐calculate local illumination and observation conditions considering the high‐resolution topography at the landing site. We analyzed the multiangular reflectance data set with a Hapke modeling approach aimed at characterizing the scattering properties of the surface. In particular, we found that the surface exhibits a spectral signature typical of mafic materials and is close to the mature mare lunar soil. The position of the in situ photometric parameters in the hockey stick diagram indicates that CE‐5 lunar soil particles are forward scattering, irregular and with a low density of internal scatters. Furthermore, we found that all the in situ data (including CE‐3/4/5) and laboratory measurements exhibit forward scattering properties, but the orbiter remote sensing measurements are backward scattering. We attribute this discrepancy to the different resolution of the two data sets: the in situ analysis focuses on the individual particles, whereas remote sensing approach is sensitive to the particle complex. The Hapke parameters we derived can provide a reference for the further comprehensive analysis of remote sensing and in situ spectral data, especially, caution is advised when applying the photometric parameters derived from in situ or laboratory spectra to the remote sensing data. Plain Language Summary: The photometric properties of particles are the external manifestation of their physical properties. The photometric parameters of particles can be retrieved by the reflectance spectra of particles, and then their physical properties can be studied. Currently, scientists have accumulated a wealth of spectral data in the study of the moon, including remote sensing detection, in situ detection, as well as laboratory measurements of lunar samples and simulants. The Chang'E‐5 (CE‐5) mission is China's first lunar sample return task. The lunar mineralogical spectrometer (LMS) onboard CE‐5's lander collected a rare in situ multiangular spectral data set. We used this data set to analyze the photometric properties of the lunar soils at the CE‐5 landing site. We found that the lunar soil particles are forward scattering, which is different from the conclusions induced from remote sensing spectral data. We attribute this discrepancy to the difference in resolution: the remote sensing spectra have a lower resolution (hundreds of meters), and its fundamental scattering unit is different from that of in situ lunar soil particles, but the particle complex composed of these particles. These findings can provide a reference for the further comprehensive analysis of remote sensing and in situ spectral data. Key Points: Thermal and topographic corrections are processed on the in situ multiangular spectral data set obtained by the CE‐5Photometric analysis of the in situ spectra indicates that CE‐5 lunar soil particles are forward scatteringCaution is advised when applying the photometric parameters derived from in situ or laboratory spectra to the remote sensing data [ABSTRACT FROM AUTHOR]

Due to the novel physicochemical properties of polymeric nanocomposites (PNCs), a remarkable role of PNCs has been accomplished in plenty of flexible optoelectronic applications. Solution cast procedure has been performed to prepare different contents (0.1, 0.5, 1.0, 5.0, and 10 wt%) of Ag1.6Cu0.2S (ACS) incorporated in PVP/PVA blend. Fourier transforms infrared and scanning electron microscope measurements were carried out to investigate the influence of ACS on PVP/PVA structure and morphology. UV–visible spectrophotometry technique was applied to examine PVP/PVA optical properties modifications. Spectroscopic analysis reveals that direct/indirect optical bandgap of PVP/PVA host shrinks from 5.21/4.95 eV (PVP/PVA0) to 4.87/4.54 eV (PVP/PVA10). Moreover, obvious enrichments in the whole linear/nonlinear optical parameters are achieved by ACS doping. For example, refractive index and dielectric constants of PVP/PVA are increased from 1.69 and 2.87 to 1.91 and 3.63 (PVP/PVA10). While two orders of magnetite enhancement in nonlinear third‐order susceptibility are achieved via 10% ACS doping. The electrical performance of ACS PNCs has been explored, which discloses remarkable enrichments in PVP/PVA DC‐electrical conductivity (σDC) and activation energy. The obtained structural, spectroscopic and electrical investigations prove that ACS PNCs could play an efficient role in plenty of optoelectronic applications. Highlights: Solution casting was used to prepare PVP/PVA loaded with Ag/CuS (ACS) NPs.FT‐IR analysis reveals successful incorporation of ACS in PVP/PVA structure.Enrichments in linear/nonlinear optical parameters are achieved by ACS doping.Electrical performance of ACS PNCs has greatly been enhanced.ACS PNCs could play an efficient role in plenty of optoelectronic applications. [ABSTRACT FROM AUTHOR]

A new azo dye was produced by mixing 1-(4-sulfophenyl)-3-methyl-5-pyrazolone with diazonium salt from luminol. The produced dye was assessed using the FT-IR, ¹HNMR, and UV-Visible spectroscopy techniques. This dye was dissolved in five polar solvents, and its UV-visible absorption spectra were measured and spectroscopically analysed at room temperature. Additionally, an atomic force microscope (AFM) was used to measure the enhancement of CO3O4 and ZrO2 nanoparticles in luminol azo 1-(4 -sulfophenyl)-3-methyl-5- pyrazolone solutions in aqueous solution. [ABSTRACT FROM AUTHOR]

Potassium aluminium gadolinium phosphate (KAGP) doped with difference contents of Sm3+ ion were synthesized by melt-quenching technique. The samples were further used to measure some physical, optical and luminescence properties. Absorption spectra show the hypersensitive transitions 6H5/2 → 6P3/2 and 6H5/2 → 6F7/2 at the wavelengths 402 and 1233 nm respectively. The photoluminescence spectra were recorded under 401 nm excitation, displayed the emission bands at 562, 597, 644 and 703 nm that corresponding to the transitions 4G5/2 → 6HJ (J = 5/2, 7/2, 9/2, 11/2) respectively, and the concentration quenching of Sm3+ showed at 1.0 mol%. Using the highest concentration of Sm3+ for emission spectra, Judd–Ofelt (J–O) analysis was performed to calculate the various radiative properties such as transition probabilities (AR), radiative lifetimes (τR), branching ratios (βR) and stimulated emission cross-section (σ(λp)) for different excited states. From the results of J–O parameter found to be Ω2 > Ω6 > Ω4 and the highest value of radiative properties was 4G5/2 → 6H7/2 transition. The decay curve for lower concentration was single exponential and became non-exponential for higher concentrations of the 4G5/2 level. According to the chromaticity coordinates (Commission Internationale de l′Eclairage), it indicated that the KAGP glass doped Sm3+ ion at 1.0 mol% lies in orange region. The KAGP glass doped concentration of Sm3+ at 1.0 mol% has potential application in developing the orange laser and suitable for optical device also. [ABSTRACT FROM AUTHOR]

The recently discovered Gaia BH1 binary system, a Sun-like star and a dark object (presumably a black hole), may significantly change our understanding of the population of binaries. The paper presents the components mass ratio (q) distributions of binary systems of different observational classes. They all show a significant shortage of low-q systems. In this work, I demonstrate (quantitatively) how our ignorance extends, and point out the importance of discovering and studying systems like Gaia BH1. In addition, an approximate mass–temperature relation and mass ratio–magnitude difference relation for main-sequence stars are presented here. [ABSTRACT FROM AUTHOR]

Oxide glasses are dielectric materials with potential applications in high‐frequency communications; hence, their dielectric properties in the gigahertz to terahertz frequency range should be investigated. In this study, the dielectric properties of silica glass and five single alkali silicate glasses were measured at 0.5–10 THz using terahertz time‐domain spectroscopy and far‐infrared spectroscopic ellipsometry. At 0.5–10 THz, the silica glass exhibited low dielectric dispersion with a low dielectric constant and loss. By contrast, the alkali silicate glasses exhibited high dielectric dispersion, and the dielectric constant and loss were higher than those of the silica glass. The shape of the dielectric dispersion profile depended on the alkali‐metal ions; it was broader for lighter ions such as Li ions and sharper for heavier ions such as Cs ions. The peak dielectric loss shifted toward a lower frequency as the weight of the alkali‐metal ions in the alkali‐silicate glass increased. To understand the dielectric dispersion, the complex permittivity was calculated using molecular dynamics simulations. The theoretical results qualitatively agreed with the experimental data. Ion dynamics analysis revealed that alkali‐metal ions vibrate and migrate under an applied electric field, which affects the dielectric constant and loss of alkali‐silicate glasses at gigahertz to terahertz frequencies. To fabricate filter devices at low temperatures, alkali metals should be added to silicate glass; therefore, a minimum amount of light alkali metals should be used to minimize the dielectric loss of the glass materials while maintaining productivity. [ABSTRACT FROM AUTHOR]

The Andromeda Galaxy was surveyed for monochromatic sources by using an objective prism optical telescope. The survey consisted of capturing 150 images of the entire galaxy using exposure times of only 10 to 20 sec, giving optical spectra of every point within the galaxy. The goal was to detect any sources, including transients lasting less than 10 s, that emit a narrow range of wavelengths (<3 nm) inconsistent with known astrophysical emission lines. Two different cameras were employed, having pixel sizes of 11 and 3.7 microns, the latter offering superior cosmic ray discrimination from monochromatic light. The 150 images revealed no monochromatic emission, neither short-lived (under 20 s) nor lasting the 30-minute duration of the sequence of exposures. Injection and recovery of synthetic monochromatic sources verified that lasers could be detected and yielded a detection threshold of 1 photon per second. At the Andromeda Galaxy, that detection threshold corresponds to a laser having a power of roughly 100 Terawatts for a benchmark 10-meter laser launcher that is diffraction-limited. Any lasers more powerful and directed toward Earth would have been detected. None were found. [ABSTRACT FROM AUTHOR]

Five novel bright orange color emitting Sm(III) complexes (C1-C5) have been synthesized via energy efficient and cost effective solution precipitation method with 5-phenyl 2-furoic acid as primary organic sensitizer and nitrogen donor neocuproine, 2, 2- bipyridyl, bathophenanthroline, and 1,10-phenanthroline as secondary ligands. All the newly synthesized metal complexes are thoroughly characterize to examine the appropriateness of the organic ligand for the sensitization process. All the outcomes of the various advanced and fundamental spectroscopic techniques validate the bonding of carboxylate group with the Sm(III) ion. The luminescence spectra reflects the dominance of magnetic dipole transition which designate the occurrence of harmonized chemical environment in the coordination sphere which is further validated by enhanced values of intensity ratio. These complexes possess suitable thermal stability with excellent photoluminescent features as confirmed by thermogravimetric analysis and photoluminescence studies. The luminescence lifetime of samarium complexes [C2-C5] is relatively long due to the synergistic effect presented by ancillary ligands. The emission color of the synthesized complexes show shift from orange to bright orange red color which is displayed through CIE color coordinates. [ABSTRACT FROM AUTHOR]

In the present paper, we performed the optical, astrometric and spectroscopic studies for the open star cluster NGC 6475 using Gaia DR3 data. Using the radial density profile, we estimated the radius of the cluster to be equal to 1.44°. It is located at a distance of 279 ± 17 pc and has a service life of 224 ± 26 Myr. The mean proper motions in RA are 268.50 ± 0.80 mas yr−1 and in DEC, they are −34.83 ± 0.70 mas yr−1. Using spectroscopic radial velocity data of Gaia DR3, the median radial velocity is −14.47 ± 1.92 km s−1. We determined the physical parameters (Teff, log g and V sin i) for 11 possible members of the B-type stars in the open cluster NGC 6475, using the Barbier–Chalonge–Divan (BCD) spectrophotometry system. We also determined the projected rotational velocity of the stars by matching them with the theoretical LTE model and located our studied stars over the HR diagram. From the 11 studied B-type stars, we found six members from them. [ABSTRACT FROM AUTHOR]

Previous studies pointed out that many observed samples of short-period binaries display a cut-off period, P cut, such that almost all binaries with periods shorter than P cut have circular orbits. This feature is probably due to long-term circularization processes induced by tidal interaction between the two stars of each binary. It seemed as if coeval main-sequence (MS) samples of open clusters display P cut that depends on the sample age. Using the unprecedentedly large sample of MS spectroscopic orbits recently released by Gaia , we have found that the P cut does not depend on the stellar age but, instead, varies with stellar temperature, decreasing linearly from 6.5 d at T eff ∼ 5700 K to ∼2.5 d at 6800 K. P cut was derived by a new algorithm that relied on clear upper envelopes displayed in the period-eccentricity diagrams. Our P cut determines both the border between the circular and eccentric binaries and the location of the upper envelope. The results are inconsistent with the theory, which assumes circularization occurs during the stellar MS phase, a theory that was adopted by many studies. The circularization has probably taken place at the pre-main-sequence phase, as suggested already in 1989 by Zahn and Bouchet, and later by Khaluillin and Khaluillina in 2011. Our results suggest that the weak dependence of P cut on the cluster age is not significant, and/or might be due to the different temperatures of the samples. If indeed true, this has far-reaching implications for the theory of binary and exoplanet circularization, synchronization, and alignment. [ABSTRACT FROM AUTHOR]

Recent development in remote sensing technology using hyperspectral reflectance or spectroscopic data has enabled rapid and ongoing progression of monitoring, mapping, and surveillance for detection of disease and improved crop management. This study describes a spectroscopy-based methodology to escalate the efficiency of present surveillance practices for detection of disease infestation viz., Alternaria blight in mustard crop. The methodology uses ground-based hyperspectral data across the spectral bands 350-2500 nm at 1 nm intervals. Two different statistical procedures such as sensitivity analysis (correlation between reflectance, 1st and 2nd derivatives with disease severity grades) and continuum removal analysis was implemented for selection of sensitive bands. In this method, we explore the combinations of different selected sensitive spectral bands and regions to separate the disease affected mustard crops from the healthy ones. The objectives of this research is to develop a novel methodology for selection of bands sensitive to Alternaria blight affected crops. The development of such methodology will provide a reliable and stable method for researchers, and remote sensing practitioners to achieve faster technique with higher accuracy to map Alternaria blight affected crops. [ABSTRACT FROM AUTHOR]

The presence of minerals formed under the occurrence of liquid water during the first billion years on Mars was a key discovery, but there is still a large number of open issues that make the study of these mineral deposits a main focus of remote sensing and laboratory studies. Moreover, even though there is extensive research related to the study of the spectral behavior of mixtures, we still lack a full understanding of the problem. The main goal of this work is the analysis of the detection limits of hydrated and carbonate phases within mixtures with basaltic-like fine regolith in the spectral region 1.0–5.5 µm (1818–10,000 cm−1). We selected two different basalt samples and mixed them with two carbonate phases: a dolomite and a calcite. Spectral features have been investigated isolating the main carbonate absorption features and overtones; deriving trends of spectral parameters such as band depth, band area, full-width-half-maximum; percentage and grain size variations. The results obtained in this work show how the presence of a basaltic component can strongly influence the appearance of the hydrated and carbonate features showing different trends and intensities depending on the grain size and percentage of the carbonate components. [ABSTRACT FROM AUTHOR]

Edible mushrooms are healthy food with high nutritional value, which is popular with consumers. With the increase of the problem of mushrooms being confused with the real and pollution in the market, people pay more and more attention to food safety. More than 167 articles of edible mushroom published in the past 20 years were reviewed in this paper. The analysis tools and data analysis methods of identification and quality evaluation of edible mushroom species, origin, mineral elements were reviewed. Five techniques for identification and evaluation of edible mushrooms were introduced and summarized. The macroscopic, microscopic and molecular identification techniques can be used to identify species. Chromatography, spectroscopy technology combined with chemometrics can be used for qualitative and quantitative study of mushroom and evaluation of mushroom quality. In addition, multiple supervised pattern-recognition techniques have good classification ability. Deep learning is more and more widely used in edible mushroom, which shows its advantages in image recognition and prediction. These techniques and analytical methods can provide strong support and guarantee for the identification and evaluation of mushroom, which is of great significance to the development and utilization of edible mushroom. [ABSTRACT FROM AUTHOR]

Purpose: High-contrast tissue characterization of thermal ablation has been desired to evaluate therapeutic outcomes accurately. This paper presents a photoacoustic (PA) characterization of thermal tissue ablation in the visible spectrum, in which higher light absorbance can produce spectral contrast starker than in the near-infrared range. Methods: Ex vivo experiments were performed to measure visible PA spectra (480-700 nm) from fresh porcine liver tissues that received a thermal dose in a range of cumulative equivalent minutes at 43°C (CEM43). The local hemoglobin lobe area between 510-600 nm and wholespectral area under the curve were evaluated to represent the transition of hemoglobin into methemoglobin (MetHb) in the target tissue. Results: The thermal process below an estimated therapeutic CEM43 threshold (80-340 minutes) presented a progressive elevation of the PA spectrum and an eventual loss of local hemoglobin peaks in the visible spectrum, closer to the MetHb spectrum. Interestingly, an excessive CEM43 produced a substantial drop in the PA spectrum. In the spectral analysis, the visible spectrum yielded 13.9-34.1 times higher PA sensitivity and 1.42 times higher contrast change than at a near-infrared wavelength. Conclusion: This novel method of PA tissue characterization in the visible spectrum could be a potential modality to evaluate various thermal therapeutic modalities at high-contrast resolution. [ABSTRACT FROM AUTHOR]

Since the proposition of the standard form of Morse potential V SM r model over the years, there has not been much attention on the potential. Its application to different studies such as the thermodynamic properties and information theory are yet to be reported to the best of our understanding. In this study, the solutions of the radial Schrödinger equation for the standard Morse potential is obtained using supersymmetric approach. The effect of the quantum number on the energy eigenvalue for the standard Morse potential is examined numerically for the hydrogen molecule (H2), lithium molecule (Li2), and potassium molecule (K2). Using the energy equation and the wave function obtained, the theoretic measures and thermodynamic properties of hydrogen, lithium, and potassium molecules are calculated via maple program. It has been shown that the energy of the standard Morse potential is fully bounded for the three molecules studied. A higher concentration of electron density corresponds to a strongly localized distribution in the position configuration. The Beckner, Bialynicki-Birula, and Mycieslki (BBM) inequality is satisfied for both the ground state and the first excited state. Finally, the product of uncertainty obtained obeyed the Heisenberg uncertainty relation. [ABSTRACT FROM AUTHOR]

The shielding and spectroscopic properties of Pr + 3 and Pr3+/Ho3+-codoped tellurite glass were investigated. The intensity parameters (Ω2 = 3.24-, Ω4 = 1.64-, Ω6 = 1.10 × 10−20 cm2) as well as the radiative lifetimes of 3F4 + 5S2 and 5I6 excited states of Ho3+ ions were equal to 301 μs and 3.0 μs, respectively. The former value appears to be much higher than that obtained from the lifetime measurement, indicating the presence of various energy transfer processes. The NIR spectrum of Pr3+/Ho3+-co-doped tellurite glass is dominated by strong Ho3+: 5I6 emission at around 1200 nm, being the result of the energy transfer from Pr3+ to Ho3+ ions. The shielding effectiveness of the prepared glasses showed good performance against high-energy photons. These findings suggest that the prepared glasses could be used in laser technology such as photodynamic therapy (PDT) treatment procedures and as shielding for radiation protection. [ABSTRACT FROM AUTHOR]

Adulterations of olive oil are performed by adding seed oils to this high-quality product, which are cheaper than olive oils. Food safety controls have been established by the European Union to avoid these episodes. Most of these methodologies require expensive equipment, time-consuming procedures, and expert personnel to execute. Near-infrared spectroscopy (NIRS) technology has many applications in the food processing industry. It analyzes food safety and quality parameters along the food chain. Using principal component analysis (PCA), the differences and similarities between olive oil and seed oils (sesame, sunflower, and flax oil) have been evaluated. To quantify the percentage of adulterated seed oil in olive oils, partial least squares (PLS) have been employed. A total of 96 samples of olive oil adulterated with seed oils were prepared. These samples were used to build a spectra library covering various mixtures containing seed oils and olive oil contents. Eighteen chemometric models were developed by combining the first and second derivatives with Standard Normal Variable (SNV) for scatter correction to classify and quantify seed oil adulteration and percentage. The results obtained for all seed oils show excellent coefficients of determination for calibration higher than 0.80. Because the instrumental aspects are not generally sufficiently addressed in the articles, we include a specific section on some key aspects of developing a high-performance and cost-effective NIR spectroscopy solution for fraud detection in olive oil. First, spectroscopy architectures are introduced, especially the Texas Instruments Digital Light Processing (DLP) technology for spectroscopy that has been used in this work. These results demonstrate that the portable prototype can be used as an effective tool to detect food fraud in liquid samples. [ABSTRACT FROM AUTHOR]

The objective of this study is to valorize two waste products which, until now, caused major problems concerning their management and impacts on the environment and health. This study concerns the sludge of the wastewater treatment station of the city of Fez-Morocco and the olive mill wastewater, which are produced, respectively, in quantities of around 51,100 t/year and 514,350 m3/year, by pyrolysis for the production of biochar. The obtained biochar was characterized by physicochemical and spectroscopic analyses. The results show that the biochar is close to neutrality and is characterized by an important organic and mineral load; further, it is endowed with a porous surface, which could facilitate the adsorption of different polluting substances, composed mainly by micropores. It is mainly composed of alcohol, phenol, carboxyl and phenyl groups, as well as other mineral elements including silica and calcite. The composition, structure and morphology of the biochar thus prepared recommend its use in various fields, such as the treatment of pollutants, organic amendment, the reinforcement of polymers and as a secondary building material. [ABSTRACT FROM AUTHOR]

Monoclonal antibodies (mAbs) are a fast-growing class of biopharmaceuticals. They are widely used in the identification and detection of cell makers, serum analytes, and pathogenic agents, and are remarkably used for the cure of autoimmune diseases, infectious diseases, or malignancies. The successful application of therapeutic mAbs is based on their ability to precisely interact with their appropriate target sites. The precision of mAbs rely on the isolation techniques delivering pure, consistent, stable, and safe lots that can be used for analytical, diagnostic, or therapeutic applications. During the creation of a biologic, the key quality features of a particular mAb, such as structure, post-translational modifications, and activities at the biomolecular and cellular levels, must be characterized and profiled in great detail. This implies the requirement of powerful state of the art analytical techniques for quality control and characterization of mAbs. Until now, various analytical techniques have been developed to characterize and quantify the mAbs according to the regulatory guidelines. The present review summarizes the major techniques used for the analyses of mAbs which include chromatographic, electrophoretic, spectroscopic, and electrochemical methods in addition to the modifications in these methods for improving the quality of mAbs. This compilation of major analytical techniques will help students and researchers to have an overview of the methodologies employed by the biopharmaceutical industry for structural characterization of mAbs for eventual release of therapeutics in the drug market. [ABSTRACT FROM AUTHOR]

Predicting the properties of glass based on compositional and structural information is a fundamental issue with enormous practical and industrial significance for the study of laser glass. Here we address this problem and demonstrate the application of phase diagram method in predicting the spectroscopic properties of Nd3+‐doped binary and ternary silicate, binary phosphate, and borate laser glasses from their initial congruently melting compounds. In particular, spectroscopic properties, such as effective linewidth (Δλeff) and fluorescence branching ratio (β) can be precisely predicted in all glass systems with an error less than 5%. Furthermore, a composition–structure–property database of Nd3+‐doped ternary silicate glass system is established and preliminarily applied to the composition design and explanation of commercial glass. This study provides interpretable predictions of the optical and spectroscopic properties for Nd3+‐doped laser glasses. [ABSTRACT FROM AUTHOR]

Through the condensation of isatin (indoline-2, 3-dione) and aniline in a 1:1 ratio, a Schiff base ligand was synthesized and characterized via (1H-NMR, mass, IR, UV-Vis) spectra. Elemental analyses, spectroscopy (1H-NMR, mass, UV-Vis), magnetic susceptibility, molar conductivity, mass spectra, scanning electron microscope (SEM), and thermal analysis have all been used to characterize a series of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) metal complexes derived from the titled ligand. The metal-to-ligand ratio is 1:1, according to the analytical data. The Schiff base ligand displayed bidentate behavior with NO coordination sites when it bonded to metal ions, as seen by the IR spectra. The magnetic moment measurement and UV-Vis spectral investigation showed the octahedral geometry of the Cr(III), Fe(III), Co(II), Ni(II), and Zn(II) complexes, whereas they suggested the tetrahedral geometry of the Mn(II), Cu(II), and Cd(II) complexes. The thermal analysis study confirmed the presence of both hydrated and coordinated water molecules in all the compounds, except for the Mn(II) complex, and showed that the complexes decomposed in three or five decomposition steps leaving the corresponding metal oxide as a residue. The ligand and its metal complexes' antibacterial efficacy were evaluated. The findings showed that the metal complexes had stronger antibacterial properties than the ligand alone. The ligand and its metal complexes' anticancer properties were also investigated. A DFT investigation is also reported to gather information regarding the electronic features of the ligand and its metal complexes. Finally, drug-likeness and ADME characteristics were also calculated as parameters. [ABSTRACT FROM AUTHOR]

Green synthesis of nanoparticles (NPs) has attracted the researcher's attention due to its rapid, cost-effective, sustainable and eco-friendly nature. Current studies were carried out to perform and investigate the green synthesis of NiO NPs with aqueous (NiO(aqueous)) and ethanolic extracts (NiO(ethanolic)) of Acacia nilotica leaves, respectively. The NPs were characterized by spectroscopic, microscopic and thermometric techniques including FTIR, Raman, XRD, SEM, TGA and DSC. The electrochemical properties, antibacterial potential and haemolytic activities of the synthesized NPs were also examined. XRD patterns revealed the face-centred cubic structures of NiO NPs and a high degree of crystallinity. The average crystallite size of NiO(aqueous) NPs was significantly smaller (16 nm) than that of NiO(ethanolic) NPs (28 nm). SEM images show that NiO NPs are spherical. The synthesized NiO NPs demonstrate good electrochemical stability at an operating potential of −0.5-0.5 V. The inhibition effect of NiO NPs(ethanol) against B. subtilis, was comparable to the ciprofloxacin. [ABSTRACT FROM AUTHOR]

Recent measurements of the reflection of the surface of a lava world provides an unprecedented opportunity to investigate different stages of rocky planet evolution. The spectral features of the surfaces of rocky exoplanets give insights into their evolution and inner workings. However, no data base exists yet that contains spectral reflectivity and emission of a wide range of potential volcanic exoplanet surface materials. Here, we first synthesized 16 possible exoplanet surfaces, spanning a wide range of chemical compositions based on potential mantle material of volcanic exoplanets guided by the metallicity of different host stars. Then, we measured their infrared reflection spectrum (2.5–28 μm), from which we obtained their emission spectra, and established the link between the composition and a strong spectral feature at 8 μm, the Christiansen feature (CF). Our analysis suggests a new multicomponent composition relationship with the CF as well as a correlation with the silica content of the exoplanet mantle. We also report the mineralogies of these materials, as possibilities for volcanic worlds. This data base is a tool to aid in the interpretation of future spectra of volcanic and lava worlds that will be collected by the James Webb Space Telescope and other missions. [ABSTRACT FROM AUTHOR]

The work describes synthesis of a bioactive molecule 2-(4-fluorophenyl)-4-(4-(4-methoxyphenyl)-5-(3-nitrophenyl)-4H-1, 2, 4-triazol-3-yl)quinoline. The characterization has been done with the help of various spectroscopic techniques followed by in-silico studies including various structural parameters viz. electrostatic potential, electrophilicity (ω), chemical potential (μ), chemical hardness (η), thermodynamic properties at various temperatures, Natural bond orbital (NBO), Non-linear optical (NLO), electric dipole moment, polarizability and first static hyperpolarizability. Reactivity descriptors were also investigated to find out the sites liable for electrophilic and nucleophilic attack. The compound was also bio-evaluated for its antimicrobial and antioxidant activity. It showed significant activity against S. typhi and a positive antioxidant activity shown by reduction in color with percentage inhibition of 89%. [ABSTRACT FROM AUTHOR]

In the optical energy gap, visible and near-IR emission of halide phosphate glasses with a composition of 40P2O5-30ZnO-20LiCl-10BaF2 in mol% doped with 3.5 × 104 ppm Pr2O3, referred to as PZLBPr, were synthesized. The UV-VIS-NIR and spectroscopic properties of these glasses were also predicted. The current glasses had broadband emission photoluminescence covering a wavelength range of 1250 to 1700 nm when excited at 455 nm. These bands for near-infrared emission luminescence relate to the transitions 1G4 → 3H5, 1D2 → 1G4, and 3H4 → 3F3, 3F4 in the optical telecommunication window. The significant PL emission wideband was caused by the radiative transition from Pr3+: 1D2 to 1G4. At 445 nm excitation, these glasses exhibited emission bands that corresponded to blue/reddish orange spectral ranges in visible ranges. The prepared glass has a high lasing quality factor (Ω4/Ω6 = 0.9), high optical energy (4.72 eV), and quantum efficiency = 87.3% with FWHM = 156 nm of transition emission from the 1D2 → 1G4 level. As a result, broadband near infrared optical amplifiers can be fabricated from the prepared glasses. [ABSTRACT FROM AUTHOR]

The manipulation of the active dye material for application in dye-sensitized solar cell (DSSC) using simple or bulky group substituents is necessary for improved dye performance. Herein, we carried out a combined experimental and theoretical studies of different alkylated novel reactive (E)-6-(2,3-dihydroxyl naphthalene diazinyl)-1H-benzoisoquinoline-1,3-dione azo-based dyes using spectral (FTIR, UV–visible, and NMR) analysis and electronic structure theory method based first principle density functional theory (DFT) calculations to investigate the molecular electronic properties, structural analysis, excitation behavior, and the theoretical potential application in photovoltaic cell. The synthesized azo dye (azoD) was theoretically modeled by varying the number of alkyl chains denoted as AzoD1, AzoD2, AzoD3, and AzoD4 to represent azo dyes having ten (10), twelve (12), fourteen (14), and sixteen (16) alkyl chain length respectively. From the natural bond orbital (NBO) analysis, the higher stabilization energies, 227.80 and 227.77 kcal/mol respectively, recorded for AzoD1 and AzoD4 may be due to extra orbital contribution by π*(N21–N22) to π*C54–C56 31.19 eV for AzoD1 and π*(N21–N22) → π*(C53–C55) 31.43 eV AzoD4 confirming that chain length affected the orbital interaction of the molecules. The driving force (ΔGinject) of electron injection into the TiO2 surface (− 1.92 to − 1.93) shown in this study is indicative that alkylated azo dyes are good for improved DSSCs performance. Again, the open circuit voltage (Voc) of 1.090 (AzoD1), 1.092 (AzoD2), 1.093 (AzoD3), and 1.095 (AzoD4) are also evidence of the suitability of azo dyes as photosensitizers. All the spectroscopic analysis, FTIR, UV–visible, and NMR combined with theoretical calculations, provided accurate data for characterizing the titled azo dye compound and showed that it has good photophysical properties. The presence of alkyl groups and chain length promoted the stability of the dyes thereby making them suitable for application in DSSCs. Increase in chain length as well enhanced the electron injection into the conduction band of the semiconductor. [ABSTRACT FROM AUTHOR]

Hybrid moieties of ethynylated-thiourea, Th1 and Th2 have been synthesised via the addition reaction between ethynyl derivatives and 4-tert-butylbenzoyl isothiocyanate in acetone, and were characterised by selected spectroscopic methods (i.e., 1H and 13C NMR, UV–visible, FT-IR) and elemental analysis. Thermogravimetric analysis indicated that Th1 and Th2 were relatively stable up to ca. 210 °C. Single-crystal X-ray diffraction was used to identify the crystal structure of Th2 in which the centre of 1-acyl thiourea moiety (-C(O)NHC(S)NH) exhibits S conformation. The Hirshfeld surface analysis has allowed visualizing the crystal packing, which is characterised by the prolonged intermolecular N–H⋯O = C and N–H⋯S = C hydrogen-bonding interactions within Th2 molecule. Electrochemical data of both compounds correspondingly exhibit irreversible redox potential processes. Besides, frontier molecular orbitals and Natural Bond Orbital population analysis were computed at the B3LYP/6-31G (d, p) level of approximation, suggesting strong delocalization of the electronic density through a conjugated π-system involving the ethynyl-phenyl and thiourea groups. Figure of molecular structure for acyl thiourea-ethynyl derivative. Two derivatives of acyl thiourea-ethynyl were synthesised and characterised by selected spectroscopic methods such as 1H and 13C NMR, UV-visible, FT-IR, elemental, thermal, electrochemical, X-ray diffraction, and density functional theory (DFT) calculation for molecular orbitals and natural bond orbital population analysis. [ABSTRACT FROM AUTHOR]

Three new bioactive nanosized supramolecular cobalt coordination polymers; {[Co2(tyr)2(Morph)2(Cl)2(H2O)2]}n (1), {[Co(Morph)6]+2[Co(bdc)(Morph)2(Cl)2]−2.3H2O}n (2) and {[Co(Morph)6]+2[Co(H2btec)(Morph)3(H2O)]−2.10H2O}n (3), where L-tyr = L-tyrosine, H2bdc = Terephthalic acid, H4btec = Pyromellitic acid and Morph = Morphline, they were prepared and characterized by elemental analysis, FT-IR and UV–VIS spectroscopies, magnetic, molar conductance, TGA/DTA, XRPD, catalytst and MM2 theoretical calculations. In all three compounds, the Morph ligand adopts a bidentate chelating coordination mode and the carboxylate anions of bdc−2 and H2btec−2 act as monodentate ligands while the tyr−1 anion act as bidentate ligand. The coordination geometry of the cobalt centers is an octahedral. The variation of carboxylates, morphline and central cobalt ions exerts a significant effect on the structures, properties and biological activity. Kinetic and thermodynamic parameters (n, E*, Z, ΔH*, ΔS* and ΔG*) were computed using Coats–Redfern equations and discussed, which confirms the second order kinetics. From the XRPD patterns, the crystal parameters as well as the particle sizes of the complexes could be evaluated. Complexes exhibit catalytic activity. The biological activity of the compounds has also been study against different bacteria and fungi. [ABSTRACT FROM AUTHOR]

Here, we report a new series of Co(II), Ni(II), Cu(II) and Zn(II) metal complexes (1–20) derived from hydrazone ligands [Nʹ-((E)-3-(4-nitrophenyl)allylidene)benzohydrazide] HL1, [Nʹ-((E)-3-(4-nitrophenyl)allylidene)nicotinohydrazide] HL2, [Nʹ-((E)-3-(4-nitrophenyl)allylidene)isonicotinohydrazide] HL3, [4-methyl-Nʹ-((E)-3-(4-nitrophenyl)allylidene)benzohydrazide] HL4 which were obtained from condensation reaction of 4-nitrocinnemaldehyde with benzo/ nicotinic/ iso-nicotinic/ p-toluic hydrazide. The structure elucidation was deduced from spectral and physicochemical techniques like 1H NMR, 13C NMR, FT-IR, UV–Vis, ESR, SEM, TGA/DTG, XRD, HRMS, molar conductance measurements and elemental analysis. Also, DFT (B3LYP/LanL2DZ) computations have been conducted for ligand and its metal complexes to study the structural and energetics behaviour. The spectral and physicochemical techniques suggested octahedral geometry of all the afforded metal complexes with hydrazone ligands in (1 M: 2L) molar ratio having molecular formula of the type [M(L1−4)2(H2O)2]. Thermal analysis suggested that the complexes were stable up to 190 °C and that water molecules are coordinated to metal ions in complexes. XRD data revealed crystalline nature of compounds and scanning electron microscopy (SEM) suggested that metal complexes have different surface morphology as compared to hydrazone ligands. In vitro antioxidant potential of synthesized compounds was assessed and investigation revealed that metal complexes have more efficiency of decolourizing the DPPH solution as compared to ligands. To ascertain the therapeutic aspects of synthesized compounds, in vitro antimicrobial assessment was performed on four bacterial strains (Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli) and two fungal strains (Candida albicans, Aspergillus niger) taking ciprofloxacin and fluconazole as reference drugs, respectively. Compounds 11, 12, 15, 16, 19 and 20 were found to be potent antimicrobial agent among the tested series. Thus, this investigation gave a vision into the structural-based modification of hydrazones and their complexation with metals could enhance biological activities.4 [ABSTRACT FROM AUTHOR]

Radio emission has been detected for all types of stars in the Hertzsprung Russell diagram. Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) low and medium-resolution spectroscopic surveys provide a good opportunity to obtain the spectroscopic properties of radio stars. We cross-matched big data from the LAMOST DR7 low resolution spectral survey with a catalogue of radio stars, and obtained 449 stellar spectra of 258 stars. We detected 185 spectra with H α emission. There are a total of 108 objects with repeated low resolution spectral observations, of which 63 show variations in the H α line over a long time, about several months. We cross-matched LAMOST DR7 medium resolution spectra with the radio star catalogue. We obtained 1319 LAMOST medium-resolution spectra of the 156 radio stars and then calculated their equivalent widths ( E W s ) of the H α line. Among them, 93 radio stars with H α emission were found from the LAMOST medium resolution spectra, and 63 objects showed short and long-term variabilities, especially on a short time scale of approximately 20 min. Finally, we estimated the minimal detectable radio flux of the FAST telescope and provided a scientific plan for studying radio stars. [ABSTRACT FROM AUTHOR]

New Cu(II), Ni(II), Co(II), and Mn(II) complexes of the gabapentin (Gpn) bidentate drug ligand were synthesized and studied using elemental analyses, melting temperatures, molar conductivity, UV–Vis, magnetic measurements, FTIR, and surface morphology (scanning (SEM) and transmission (TEM) electron microscopes).The gabapentin ligand was shown to form monobasic metal:ligand (1:1) stoichiometry complexes with the metal ions Cu(II), Ni(II), Co(II), and Mn(II). Molar conductance measurements in dimethyl-sulfoxide solvent with a concentration of 10−3 M correlated to a non-electrolytic character for all of the produced complexes. A deformed octahedral environment was proposed for all metal complexes. Through the nitrogen atom of the –NH2 group and the oxygen atom of the carboxylate group, the Gpn drug chelated as a bidentate ligand toward the Mn2+, Co2+, Ni2+, and Cu2+ metal ions. This coordination behavior was validated by spectroscopic, magnetic, and electronic spectra using the formulas of the [M(Gpn)(H2O)3(Cl)]·nH2O complexes (where n = 2–6).Transmission electron microscopy was used to examine the nanostructure of the produced gabapentin complexes. Molecular docking was utilized to investigate the comparative interaction between the Gpn drug and its four metal [Cu(II), Ni(II), Co(II), and Mn(II)] complexes as ligands using serotonin (6BQH) and dopamine (6CM4) receptors. AutoDock Vina results were further refined through molecular dynamics simulation, and molecular processes for receptor–ligand interactions were also studied. The B3LYP level of theory and LanL2DZ basis set was used for DFT (density functional theory) studies. The optimized geometries, along with the MEP map and HOMO → LUMO of the metal complexes, were studied. [ABSTRACT FROM AUTHOR]

A new phthalocyanine 1 was synthesized, containing 2-aminophenoxy groups as tetra from its peripheral positions and indium (III) acetate in its cavity. The structure of 1 was illuminated by elemental analysis, FTIR, UV-vis and fluorescence spectroscopy techniques It is well soluble in solvents such as polar and nonpolar solvent types. Its aggregation properties have been studied both in the solvents mentioned above and in Dimethyl sulfoxide at different concentrations. Its aggregation properties were examined in these solvents as well as in Dimethyl sulfoxide at certain different concentration ranges. With these determined spectroscopic properties, it can be a candidate for use in various technological applications. [ABSTRACT FROM AUTHOR]

The fabrication and spectroscopic characterization of varying content of Y3+ doped bismuth titanate borosilicate glasses by the melt quenching technique are described. The nature of glass system composition was established using XRD spectra analysis. The manufactured glasses' molar volume reduced while their density and refractive index continued to increase. UV transmission, absorption, polarizability, and basicity are all found to be highly sensitive to Y2O3 content. The optical bandgap and Urbach energy have been discussed in detail. It was observed that, as Y2O3 increase, the optical bandgap increases, while Urbach energy decreases. Based on the results of the calculations of molar Refractivity, molar polarization, polarizability, optical basicity and dispersion, the fabricated glasses are thought to be very semi-covalent. Metallization of the present glasses are increased. [ABSTRACT FROM AUTHOR]

Sixteen Co(II), Ni(II), Cu(II) and Zn(II) complexes were synthesized by four Schiff base ligands 4-((4-(benzyloxy)-2-hydroxybenzylidene)amino)-[1,1'-biphenyl]-3-ol (H2L1), 6-((4-(benzyloxy)-2-hydroxybenzylidene)amino)-4,6-dichloro-3-methylphenol (H2L2), 2-((4-(benzyloxy)-2-hydroxybenzylidene)amino)-6-chloro-4-nitrophenol (H2L3), 5-(benzyloxy)-2-(((2-hydroxyphenyl)imino)methyl)phenol (H2L4) obtained from condensation reaction of 4-(benzyloxy)-2-hydroxybenzaldehyde with various aminophenol derivatives and well characterized by various spectroscopic techniques (FT-IR, UV–Vis, NMR, ESR, SEM, fluorescence), mass spectrometry, elemental analysis (CHN) and physical studies (TGA, XRD, molar conductance, melting point). The various characterization data suggested that the Schiff base ligands coordinated via nitrogen of azomethine and deprotonated phenolic oxygen atoms (ONO) with metal ions in 1:1 molar ratio having general formula [M(L1−4)(H2O)2(CH3COO)]. Low values of molar conductance of compounds suggested their non-electrolytic nature. The thermal decomposition of complexes indicated that metal complexes are stable up to 150 °C and give metal oxide as end product. Using SEM analysis, the surface morphology of the synthesized compound was determined. The compounds (1–20) were evaluated for their in vitro antioxidant activity and found that the synthesized metal(II) complexes are highly potent and also show good efficiency for decolourizing the purple-coloured solution of DPPH compared to free Schiff base ligands and Cu(II) complexes were most potent having IC50 value from 2.98 to 3.89 µM range. The compounds (1–20) were assayed for their in vitro antimicrobial activities against four bacterial strains (S. aureus, B. subtilis, P. aeruginosa, E. coli) and two fungal strains (A. niger, C. albicans) by serial dilution method, and it was found that the metal(II) complexes are more noxious than free Schiff base ligands. The antimicrobial activity results showed that the complexes 10, 11, 14 and 15 were most active compounds. Antifungal activity of complex 11 (Cu(L2)(CH3COO)(H2O) against C. albicans was found to be comparable to standard drug. The molecular docking of ligand H2L2 (2) and its Cu(II) complex (11) with enzyme C. albicans sterol 14-alpha demethylase suggested the hydrophobic binding. Furthermore, in silico study stressed that the compounds may be used as orally active drugs. The synthesized compounds (1–20) were screened for in vitro antimicrobial activity. Copper complex (11) was found to be the most potent antimicrobial agent and which is held by hydrophobic interactions in the active site of the enzyme C. albicans sterol 14-alpha demethylase. [ABSTRACT FROM AUTHOR]

The thermal condensation of 3-(2-Furyl)acrolein with 2-Amino-6-ethoxybenzothiazole generated a new Schiff base, (1E,2E)-N-(6-ethoxybenzo[d]thiazol-2-yl)-3-(furan-2-yl)prop-2-en-1-imine (L), with general formula of C16H14N2O2S. Also, a series of lanthanide complexes of gadolinium, samarium, and neodymium (La–Lc) were synthesized utilizing acetonitrile as the solvent and triethylamine as a buffer and catalyst. Based on elemental analysis, mass spectroscopy, and FTIR analysis, all of the Bis-(1E,2E)-N-(6-ethoxybenzo[d]thiazol-2-yl)-3-(furan-2-yl)prop-2-en-1-iminetri-nitratolanthanide(III) complexes with the general formula [LnL2(NO3)3]·H2O are solids with a 2:1 molar ratio (ligand: metal). Based on conductivity estimates, they are nonelectrolytes and monoatomic paramagnetic according to the magnetic moment measurements, and one mole of lattice water was found after thermal gravimetric measurements and FTIR analysis. Therefore, the lanthanide complexes show a ten-coordination structure with a deformed bicapped square antiprismatic. The Schiff base and its complexes were screened for their antimicrobial, antifungal, antioxidant, and antitumor properties. Their antimicrobial and antifungal activities were strong, and they also produced good antioxidant and antitumor effects. [ABSTRACT FROM AUTHOR]

This review highlighted the analysis techniques of hydroxamic acid (HAs) and Organotin (IV) Hydroxamates. Different isomerism, keto and enol form, as well as, intra and inter hydrogen bonding are confirmed through spectroscopic studies. In addition all organotin (IV) complexes geometries were studied and explained in this review depending on different analysis techniques done by researchers. Our study is not unique but it gives your attention to be more concern if you will deal with these types of compounds regarding to the functional groups, isomerism, structural information and its geometry. [ABSTRACT FROM AUTHOR]

We present multi-epoch optical and near-infrared observations of the highly reddened, Fe  ii class slow Nova V2891 Cygni. The observations span 15 months since its discovery. The initial rapid brightening from quiescence, and the presence of an ∼35-d long pre-maximum halt, is well documented. The evidence that the current outburst of V2891 Cyg has undergone several distinct episodes of mass ejection is seen through time-varying P Cygni profiles of the O  i 7773 Å line. A highlight is the occurrence of a dust formation event centred around approximately +273 d, which coincides with a phase of coronal line emission. The dust mass is found to be |$\sim\!{0.83{-}1.25} \times 10^{-10}\ \mathrm{M}_{\odot }$|⁠. There is strong evidence to suggest that the coronal lines are created by shock heating rather than by photoionization. The simultaneous occurrence of the dust and coronal lines (with varying velocity shifts) supports the possibility that dust formation is shock induced. Such a route for dust formation has not previously been seen in a nova, although the mechanism has been proposed for dust formation in some core-collapse supernovae. Analysis of the coronal lines indicates a gas mass and temperature of 8.35–8.42 × 10−7 M⊙ and ∼(4.8–9.1) × 105 K, respectively, and an overabundance of aluminium and silicon. A Case B analysis of the hydrogen lines yields a mass of the ionized gas of (8.60 ± 1.73) × 10−5 M⊙. The reddening and distance to the nova are estimated to be E (B − V) = 2.21 ± 0.15 and d = 5.50 kpc, respectively. [ABSTRACT FROM AUTHOR]

Newly phthalocyanine derivative which carries 2,6-dimethoxyphenoxy bioactive groups as tetrakis from non-peripheral positions of the phthalocyanine ring and contains strontium (II) as an alkaline earth metal ion in its cavity was synthesized. Its structure was characterized by elemental analysis, fourier transform infrared, ultraviolet–visible, proton nuclear magnetic resonance, carbon-13 nuclear magnetic resonance and matrix assisted laser desorption/ionization time-of-flight mass spectroscopic techniques. Its thermal properties were determined using thermogravimetric analysis and differential scanning calorimetry. The solubility and aggregation behavior in polar protic, polar aprotic and non-polar solvents were determined. Also, its aggregation behavior was studied at a range of different concentrations in dimethyl sulfoxide. The photophysical properties (fluorescence quantum yield, fluorescence lifetime, natural radiation lifetime, non-radiative lifetime, rate constant for fluorescence, non-radiative rate constant and observed fluorescence decay rate constant values) of newly strontium(II) phthalocyanine were determined in dimethyl sulfoxide. In addition, the spectroscopic, thermal and photophysical properties of newly strontium(II) phthalocyanine were also compared with its counterparts reported in the literature. The findings of this work can be useful to those systems involving changes in the forms analogous to the compound studied. In addition, newly strontium(II) phthalocyanine with particularly sufficient and enhanced photophysical properties, could be a photosensitizer candidate for photocatalytic applications. [ABSTRACT FROM AUTHOR]

Six samples of Pr3+ ions doped potassium aluminum gadolinium phosphate (KAGP) glasses were synthesized using the melt-quenching method. The values of density and refractive index of glasses tend to rise with the concentration of Pr2O3 due to increased interaction between the Pr3+ ions and non-bridging oxygen. Optical absorption spectra and luminescence have been investigated. Hypersensitive transitions were identified by the highest intensity of absorption spectra, which recorded at the wavelengths of 444 and 1527 nm corresponding transitions 3H4 → 3P2 and 3H4 → 3F3. The emission bands of Pr3+ ions in the visible bands were observed under the excitation 444 nm. Among them emission bands at 597 nm (1D2 → 3H4) showed highly intensity and concentration quenching of emission faster than those of 3P0 and 3P1 due to the cross-relaxation. The Commission International De I'Eclairage (CIE) 1931 chromaticity coordinates of KAGPPr4 glasses lie in yellowish-orange region to orange region. Based on the studies characteristics, Pr3+ 0.5 mol% doped KAGP glasses are suitable for guided as a great host that can emit yellowish-orange laser and suitable for optical device also. [ABSTRACT FROM AUTHOR]