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101.
Sheng Yinghong Venkatraman Ramaiyer Kwiatkowski Józef S. Majewska Joanna Leszczynski Jerzy 《Structural chemistry》2003,14(5):511-525
The molecular geometrical parameters, rotational constants, dipole moments and vibrational infrared properties of a series of phosphoryl compounds (OPX
i
Y
j
Z
k
, X, Y, Z = F, Cl, Br; i+ j + k = 3) and their thio analogs are predicted by density functional and MP2 calculations using the 6-311G(2d,2p) basis set. Both methods yielded similar results. The predicted molecular parameters and the vibrational Raman and infrared spectra agree well with the available experimental data. The Raman Scattering Activities (RSA) and depolarization ratios (Dep) of the molecules are obtained by DFT calculations. Considering the different substitution modes of various halogen atoms, the resultant changes in the geometrical and vibrational properties are discussed. Such studies permit detailed information to be obtained concerning unknown molecules and can define the guidelines for synthesizing molecules of particular characteristics. 相似文献
102.
Mari Sithambaram Karthikeyan Bantwal Shivarama Holla Balakrishna Kalluraya Nalilu Suchetha Kumari 《Monatshefte für Chemie / Chemical Monthly》2007,138(12):1309-1316
Summary. A series of dichlorofluorophenyl containing triazolothiadiazoles were obtained by cyclocondensation of triazole with substituted
benzoic, aryloxyacetic, and anilinoacetic acids using POCl3 as cyclizing agent. The structures of the newly synthesized compounds were characterized and confirmed by IR, 1H NMR, mass spectra, and elemental analysis. Selected compounds were screened for their antitubercular activity against Mycobacterium tuberculosis. The compound bearing 2,4-dichloro-5-fluorophenyl moiety at position 3, and 6 of the triazolothiadiazole showed excellent
activity in vitro primary screening. Compounds with 3-chloro-4-fluorophenyl and 4-fluorophenoxymethyl moieties at position 6 of the triazolothiadiazole
showed very good analgesic activity. Triazolothiadiazole with 4-chlorophenyl, 4-fluoro-3-phenoxyphenyl, and 2,4-dichloro-5-fluorophenyl
moieties showed excellent antimicrobial activity against the tested strains at 6.25 μg cm−3 concentrations. 相似文献
103.
Polymer composite foams or syntactic foams containing 0.9, 1.76, 2.54, 3.54 and 4.5 vol% of E-glass short fibers were processed and subjected to a three-point bending test. The results show that the flexural modulus increased with fiber content, with the exception of 1.76% and 3.5% of fibers. This deviation was due to a higher void content for 1.76% and a non-uniform distribution of fibers in the polymer composite foam system for 3.5%. However, in general, the incorporation of chopped strand fibers improved the flexural behavior of the syntactic foam system without much variation in density, thus making the reinforced syntactic foams act as improved core materials for sandwich and other structural applications. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
104.
Development and investigation of the flexible hydrogen sensor based on ZnO-decorated Sb2O3 nanobelts
Natarajan Pradeep Gopal Tamil Selvi Uma Venkatraman Quyet Van Le Soon Kwan Jeong Saravanan Pandiaraj Abdullah Alodhayb Muthumareeswaran Muthuramamoorthy Andrews Nirmala Grace 《Materials Today Chemistry》2021
Hydrogen is regarded as the next-gen fuel for vehicles to avoid the emission of toxic gases, which needs a continuous monitoring of the concentration level. In the design of the H2 sensor, especially of flexible type, a sensing layer will be blended, which affects the sensing performance of the device. Based on this concern, the present investigation is carried out to understand the effect of the bending angle toward the sensing performance of bare and ZnO (n-type)-decorated Sb2O3 (p-type) nanobelt–based sensors for hydrogen gas. The sensing element was prepared by the thermal chemical vapor deposition followed by the drop-casting method. Furthermore, the role of the zinc precursor (molar concentration—1 M–3 M) on the preparation of ZnO-decorated Sb2O3 nanobelts was studied. Various techniques were used to confirm the formation of ZnO-decorated nanobelts such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), and Fourier transform infrared spectroscopy (FTIR). From these analyses, 1 M concentration of the zinc precursor shows uniform distribution of nanoparticles over the surface of Sb2O3 nanobelts. However, agglomeration was observed when the concentration of the zinc precursor increases from 1 M to 3 M. Later, the prepared nanobelts were deposited on the OverHead Projector (OHP) sheet by the doctor blade method for sensing hydrogen gas at 100 °C at a concentration of 1000–3000 ppm. In addition to it, the effect of the substrate bending angle (0°, 45°, 60°, and 90°) was analyzed at a fixed concentration of H2 gas (1000 ppm). From this study, it is clear that the highest sensing response was achieved for 1 M decorated nanobelts compared with bare as well as other concentrations because of uniform distribution of nanoparticles on the surface of nanobelts. Moreover, the prepared sample demonstrates better sensing performance with the bending of substrates, which suggests that the prepared sensor could be used for flexible electronic devices. The prepared nanobelts show a good H2 gas–sensing response even with bending of the substrates. The work suggests that the prepared sensor is applicable for flexible electronic devices. 相似文献
105.
A microwave-assisted persulfate oxidation method followed by ion chromatographic determination of nitrate was developed for total nitrogen determination in atmospheric wet and dry deposition samples. Various operating parameters such as oxidation reagent concentrations, microwave power, and extraction time were optimized to maximize the conversion of total nitrogen to nitrate for subsequent chemical analysis. Under optimized conditions, 0.012 M K2S2O8 and 0.024 M NaOH were found to be necessary for complete digestion of wet and dry deposition samples at 400 W for 7 min using microwave. The optimized extraction method was then validated by testing different forms of organic nitrogen loaded to pre-baked filter substrates and NIST SRM 1648 (urban particulate matter), and satisfactory results were obtained. In the case of wet deposition samples, standard addition experiments were performed. The suitability of the method for real-world application was assessed by analyzing a number of wet and dry deposition samples collected in Singapore during the period of March-April 2007. The organic nitrogen content was 15% (wet) and 30% (dry) of the total nitrogen. During the study period, the estimated wet fluxes for nitrate (NO3−), ammonium (NH4+), organic nitrogen (ON), and total nitrogen (TN) were 16.1 ± 6.5 kg ha−1 year−1, 11.5 ± 5.7 kg ha−1 year−1, 3.8 ± 1.5 kg ha−1 year−1and 31.5 ± 13.2 kg ha−1 year−1, respectively, while the dry fluxes were 2.5 ± 0.8 kg ha−1 year−1, 1.4 ± 0.9 kg ha−1 year−1, 2.3 ± 1.4 kg ha−1 year−1 and 7.5 ± 2.6 kg ha−1 year−1, respectively. 相似文献
106.
Venkatraman Senthil Kumar Choudhary Rajan Genasan Krishnamurithy Murali Malliga Raman Raghavendran Hanumantha Rao Balaji Kamarul Tunku Suresh Anushree Abraham Jayanthi Venkateswaran Seshasailam Livingston Abel Swamiappan Sasikumar 《Journal of Sol-Gel Science and Technology》2021,100(3):506-516
Journal of Sol-Gel Science and Technology - Biocompatibility and bacterial infections are the primary concerns associated with the current bone graft substitutes. The application of... 相似文献
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