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Two cardinal fish species, Apogonichthyoides sialis (Jordan & Thompson, 1914) and Ostorhinchus fleurieu Lacepède, 1802 and one oxudercid goby, Trypauchenichthys sumatrensis Hardenberg, 1931 are reported herein for the first time from the coastal waters of Odisha, India. This paper deals with the diagnostic characters and distributional information of all these three species. The confusion in the identity of reported apogonids along the Odisha coast is cleared, while the report of oxudercid goby forms only the second record from India. [ABSTRACT FROM AUTHOR]

Sb-modified alkali bismuth titanate Li0.5Bi0.5−xSbxTiO3 (x = 0 and 0.1) compounds are prepared using the method of solid-state-reaction route. The XRD exploration in environmental conditions confirms the development of new compounds having single-phase orthorhombic crystal structures. Non-uniformly distributed grains are noticed in SEM micrographs for both compounds. The electric & dielectric behavior is analyzed by use of an impedance analyzer. The exploration of the dielectric behaviors of both compounds in a wide frequency range (100 Hz–1 MHz) & temperature range (30–500 °C) suggests that these characteristics are strongly dependent on frequency & temperature. Activation energy assessed from temperature variation of ac-conductivity in various zones recommends that the electric transport phenomenon obeys the Arrhenius equation and shows a mixed type of conductivity. [ABSTRACT FROM AUTHOR]

Sb-modified lithium bismuth titanate Li0.5Bi0.3Sb0.2TiO3 is prepared following the mixed oxide method. The development of a new compound with a single-phase orthorhombic crystal structure is approved from the XRD analysis at environmental temperature. The electrical behavior like dielectric and electrical conductivity are analyzed in a wide temperature as well as frequency range by the impedance analyzer, which exhibits that these properties effectively depend on frequency and temperature. The ac conductivity versus temperatures plots obeys the Arrhenius relation and confirm the presence of the mixed type of conductivity process like space charge conductivity created from oxygen ion vacancies, ionic-polaronic conductivity, and so on, in the sample. Ac conductivity versus frequency spectra is as per Jonscher's Universal Power law. [ABSTRACT FROM AUTHOR]

BaBi4Zr2Sn2O15, a modified ceramic sample belonging to the oxide family of layered ferroelectrics, is synthesized using the mixed oxide process after firing for calcination at 810 °C for 6 hrs. XRD study of the compound exhibits the growth of an orthorhombic single-phase structure at atmospheric temperature. The electrical properties of the sample are investigated in a broad temperature range (30–500 °C) and frequency range (100 Hz - 106 Hz). The dielectric properties recommend the transition from ferro to paraelectric state at 410 °C which is much more than room temperature. The impact of frequency and temperature on complex immittance parameters (impedance and modulus) are analyzed by an impedance analyzer in broad frequencies and temperature ranges. The electrical properties show; (i) the existence of semiconductor-like negative temperature coefficients of resistance behavior, (ii) evidence of electrical relaxation phenomena as a function of temperature, and (iii) the existence of single electrical relaxation ascribed to the existence of grain contribution to the electric properties. [ABSTRACT FROM AUTHOR]

BaBi4Sn4O15, a Sn-modified ceramic sample of layered ferroelectric oxide family, is developed using a high-temperature mixed oxide route after firing for calcination at 810 °C for 6 h in steps of 50 °C starting from 600 °C. An introductory XRD study of the compound displays the development of the new orthorhombic structured single-phase compound at atmospheric conditions. The electrical behaviors of the compound are investigated in a wide temperature span (30–500 °C) and frequencies ranging from 0.1 kHz to 1 MHz using an impedance analyzer. Dielectric behavior informs that the compound has a phase transition from Ferro to Paraelectric at 370 °C, which is well above room temperature. The impact of temperature and frequency on complex immittance parameters (impedance and modulus) is analyzed using an LCR meter in a broad temperature & frequency span. The electrical properties confirm; (a) the existence of semiconductor-like NTCR (negative temperature coefficients of resistance) behavior, (b) the evidence of the electric relaxation process as a function of temperature, (c) the existence of electric relaxation ascribed to the simultaneous contribution of bulk & bulk interfaces to the electrical behavior, and (d) presence of the non-Debye type relaxation phenomena. The frequency-dependent conductivity follows Jonscher's universal power law. [ABSTRACT FROM AUTHOR]

Organometallic compounds conjugates play a vital role in new drug discovery, in which Schiff base is useful as a ligand in consideration with different metals. Schiff base mostly encouraged due to its versatile activity due to the presence of a unique Imine (C=N) group. An attempt has been taken to synthesize a Schiff base by using salicylaldehyde and ethylene diamine which further design for the incorporation of salts of Cu, Ni and Zn metals separately. The ligand and its metal complexes have been carried out several characterization studies like elemental analysis, molar conductance, UV, IR and H1NMR. DPPH antioxidant potential and antimicrobial effect against four species Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, and Staphylococcus aureus have been done with the ligand and all its metal complexes. The result revealed that metal incorporation in the Schiff base ligand enhanced the antioxidant potential as well as remarkable antimicrobial effect. [ABSTRACT FROM AUTHOR]

In this article, we prove the finiteness of the positive integral solutions of ... for any given integer l > 1 and an odd integer k ≥ 1. Moreover, when k = 3 and l = 2, 3 and 5, we explicitly compute the positive integral solutions using the elliptic logarithmic method. [ABSTRACT FROM AUTHOR]

Introduction: With up to 8.55 wt% carbon [1], ureilites are the most carbon-rich meteorites. Graphite is the most abundant carbon allotrope, typically located in interstitial sites between silicate grains. Main group ureilites have experienced varying degrees of shock processing, altering their texture [e.g., 2]. Understanding the carbon mineralogy is crucial for interpretations regarding the processing of the ureilite parent body (UPB) [e.g., 3, 4], the debated origin of diamonds [e.g., 5-7], and graphite-based geothermometry [e.g., 8]. Methods: Raman spectra were obtained in 14 samples with a IDR-Micro-532 micro-Raman spectrometer. A Nd:YAG laser with a wavelength of 532 nm, and a laser power of 1.1 mW on the sample surface was used. An analysis consisted of a measurement time of 10 s with 5 accumulations. The statistical evaluation included baseline subtraction, peak identification, and the extraction of selected parameters (e.g., G band position and FWHM). Results: Based on the texture, the investigated samples can be catergorized into coarse-grained and fine-grained ureilites. The G band positions of graphite in coarse-grained ureilites cluster in a confined range between 1580-1583 cm-1, corresponding to crystalline graphite. Shock indicators in olivine [cf. 9] suggest that these coarsegrained samples have experienced relatively low shock pressures up to 15-20 GPa. In contrast, the Raman signatures obtained in fine-grained ureilties show a large variability and significantly higher G band positions/FWHMs, which can be attributed to a high degree of crystallographic disorder. Overall, the G band position and the G band FWHM show a nearly linear positive correlation. Discussion: A strong correlation between the texture (coarse-grained and fine-grained) and the Raman signature of graphite (crystalline graphite and disordered graphite/poorly graphitized carbon) can be observed. This raises the question, which underlying process is responsible for the increased crystallographic disorder present in graphite in fine-grained ureilites? One key observation is that the carbon phases in fine-grained ureilites often occur in textural units, which resemble the shape of graphite grains found in coarse-grained ureilites. This suggests that graphite was highly crystalline in the first place, and was subsequently replaced/modified by parent body processing. The resulting carbon phases in fine-grained ureilites are considerably more diverse compared to coarse-grained ureilites, where graphite is by far the dominant carbon allotrope. Most likely, the underlying mechanism is related to the same process, which lead to mosaicism and the visible fragmentation of silicates. In this case, the process should be related to post-accretionary shock, induced by high velocity impacts. Yet, it is unclear whether disordered graphite is a direct product of the transformation from highly crystalline graphite, or if disordered graphite might also result from the back-transformation of diamond. Conclusion: The parent body processing of ureilties has a significant effect on the carbon mineralogy. The G band parameters of graphite in finegrained and coarse-grained ureilites form two clusters, which plot on a nearly linear trend reflecting crystallographic order. Presumably, the underlying process is related to the post-accretionary shock processing of the ureilite parent body. [ABSTRACT FROM AUTHOR]