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1.
The dependence of the beam propagation factor (M
2 parameter) with the absorbed pump power in the case of monolithic microchip laser under face-cooled configuration is extensively
studied. Our investigations show that the M
2 parameter is related to the absorbed pump power through two parameters (α and β) whose values depend on the laser material properties and laser configuration. We have shown that one parameter arises due
to the oscillation of higher order modes in the microchip cavity and the other parameter accounts for the spherical aberration
associated with the thermal lens induced by the pump beam. Such dependency of M
2 parameter with the absorbed pump power is experimentally verified for a face-cooled monolithic microchip laser based on Nd3+ -doped GdVO4 crystal and the values of α and β parameters were estimated from the experimentally measured data points. 相似文献
2.
Trabecular bone fracture is closely related to the trabecular architecture, microdamage accumulation, and bone tissue properties. Primary constituents of trabecular tissue are hydroxyapatite (HA) mineralized type-I collagen fibers. In this research, dynamic fracture in two dimensional (2-D) micrographs of ovine (sheep) trabecular bone is modeled using the mesoscale cohesive finite element method (CFEM). The bone tissue fracture properties are obtained based on the atomistic strength analyses of a type-I collagen + HA interfacial arrangement using molecular dynamics (MD). Analyses show that the presented framework is capable of analyzing the architecture dependent fracture in 2-D micrographs of trabecular bone. 相似文献
3.
Heavy ion irradiation in the electronic stopping power region induces macroscopic dimensional change in metallic glasses and introduces magnetic anisotropy in some magnetic materials. The present work is on the irradiation study of ferromagnetic metallic glasses, where both dimensional change and modification of magnetic anisotropy are expected. Magnetic anisotropy was measured using Mössbauer spectroscopy of virgin and irradiated Fe40Ni40B20 and Fe40Ni38Mo4B18 metallic glass ribbons. 90 MeV 127I beam was used for the irradiations. Irradiation doses were 5×1013 and 7.5×1013 ions/cm2. The relative intensity ratios D 23 of the second and third lines of the Mössbauer spectra were measured to determine the magnetic anisotropy. The virgin samples of both the materials display in-plane magnetic anisotropy, i.e., the spins are oriented parallel to the ribbon plane. Irradiation is found to cause reduction in magnetic anisotropy. Near-complete randomization of magnetic moments is observed at high irradiation doses. Correlation is found between the residual stresses introduced by ion irradiation and the change in magnetic anisotropy. 相似文献
4.
Excess enthalpies of mixing H
m
E
of tetrahydrofuran and tetrahydropyran with trichloromethane, tetrachloromethane, 1,2-dichloroethane, 1,1,2-trichloroethane and 1,1,2,2-tetrachloroethane have been determined at 26.9°C and are found to be negative over the entire composition range for both sets of the ether mixtures. H
m
E
decreases in the sequence; dichloroethane > tetrachloromethane > trichloroethane > trichloromethane > tetrachloroethane. The results are explained on the basis of strong O...H-C and weak Cl...O specific interactions. Flory's theory has been used to correlate the experimental data with good agreement found between the theoretical and experimental values of H
m
E
. 相似文献
5.
Josephson effects have been observed in bulk samples of Y-Ba-Cu-O. The magnitude of the zero-voltage current is found to change
systematically with externally applied small magnetic fields of a few mG. It is also found to vary when samples are irradiated
with microwaves. These observations suggest the presence of inter-grain Josephson junctions. 相似文献
6.
R. S. Tomar Prakash Bhartia 《International Journal of Infrared and Millimeter Waves》1986,7(9):1281-1295
New design data for an open suspended microstripline is reported. Two most commonly used substrate materials, namely RT-Duroid (r=2.22) and fused quartz (r=3.78) are considered. Effects of dispersion and strip thickness are included in the results which are based on a fullwave spectral-domain analysis. The data, which is computed over the complete practical ranges of frequency and parameter values, is much more reliable than the currently available quasistatic results. 相似文献
7.
Dr. Mostakim SK Dr. Soumitra Barman Shounik Paul Ratnadip De Dr. S. S. Sreejith Dr. Helge Reinsch Dr. Maciej Grzywa Dr. Norbert Stock Prof. Dr. Dirk Volkmer Dr. Shyam Biswas Prof. Dr. Soumyajit Roy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(12):4098-4107
A Zr-based metal-organic framework has been synthesized and employed as a catalyst for photochemical carbon dioxide reduction coupled with water oxidation. The catalyst shows significant carbon dioxide reduction property with concomitant water oxidation. The catalyst has broad visible light as well as UV light absorption property, which is further confirmed from electronic absorption spectroscopy. Formic acid was the only reduced product from carbon dioxide with a turn-over frequency (TOF) of 0.69 h−1 in addition to oxygen, which was produced with a TOF of 0.54 h−1. No external photosensitizer is used and the ligand itself acts as the light harvester. The efficient and selective photochemical carbon dioxide reduction to formic acid with concomitant water oxidation using Zr-based MOF as catalyst is thus demonstrated here. 相似文献
8.
Kar Aishwarya S. Rao Ankita Sahu Manjulata Kumar Shiny S. Tomar B. S. 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(3):1667-1674
Journal of Radioanalytical and Nuclear Chemistry - Plutonium recovery is inevitable from plutonium bearing alumina crucibles generated over the years as part of carbon analysis during chemical... 相似文献
9.
10.
Transition metal complexes of Mn(II) and Ni(II) have been synthesized with novel bioactive Schiff's base ligand. Schiff's base ligand i.e. benzoylacetone‐bis(2‐amino‐4‐methylbenzothioazole) has been synthesized via condensation reaction between 2‐amino‐4‐methylbenzothioazole and benzoylacetone in 2:1 ratio, respectively. Synthesized ligand has been characterized using elemental analysis, infra‐red, 1H–NMR and mass spectroscopy techniques. Characterization of complexes was based on magnetic moment, molar conductance, elemental analysis, electronic spectra, infra‐red and EPR spectroscopic techniques. Molar conductance data suggest that metal complexes are non‐electrolytic in nature. Therefore, these complexes are formulated as [M(L)X2], where M = Mn(II), Ni(II), L = Schiff's base ligand, X = Cl?, CH3COO?, NO3?. Data of characterization study suggest octahedral geometry for Mn(II) and Ni(II) complexes. Geometry of metal complexes was also optimized with the help of computational study i.e. molecular modelling. Computational study also suggests octahedral geometry for complexes. Free ligand as well as its all metal complexes have been screened against the growth of pathogenic bacteria (E.coli, S.aureus) and fungi (C.albicans, C.krusei, C.parapsilosis, C.tropicalis) to assess their inhibition potential. The inhibition data revealed that metal complexes exhibit higher inhibition potential against the growth of bacteria and fungi microorganisms than free ligand. 相似文献