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排序方式: 共有101条查询结果,搜索用时 31 毫秒
91.
Suresh Kumar Vikas Kalia Madhusudan Goyal Sudarshan Kumar Hariom Dahiya Chandrabhan Verma M.A. Quraishi 《印度化学会志》2022,99(5):100421
Synthesis of 2-(phenoxymethyl)-5-phenyl-1, 3, 4-oxadiazole (2POM5PO) and corrosive inhibitive properties studied via weight loss (W.L.) measurement, electrochemical impedance spectroscopy, potentiodynamic polarisation measurements. Scanning Electron Microscope attached with Energy-dispersive X-ray spectroscopic methods were performed to notice morphological changes. These data were observed at a diversified dosage and temperatures the compound for 12 h s immersion of M.S. sheets in 1 M HCl electrolyte through W.L. measurements, furthermore inferred that the inhibition efficiency expanded with slow augmentations in the dosage of each moiety. The maximum inhibitory efficiency was determined which is 88.41% at 300 ppm and 298 K. E.I.S. studies demonstrated that charge transfer resistance increased on concentration increment, confirming each molecule's prohibitive attitude. Potentiodynamic polarisation plots revealed that the compounds displayed mixed type behavior. The Langmuir adsorption model was suited best, proving moiety act as a good corrosion controlling compound in 1 M Hydrochloric acid media. Computational study shows a good correlation with experimental results. 相似文献
92.
Mukherjee S Nagar S Mullick S Mukherjee A Saha A 《Journal of chemical information and modeling》2007,47(2):475-487
Research on Selective Estrogen Receptor Modulators (SERMs) has been driven by interest in discovering target selective molecules. In view of such significance, the present work explored the pharmacophores of estrogen receptor (ER) subtypes specific binding affinities of diverse compounds belonging to the category of bridged bicyclic-1,1-diarylethylene derivatives. Implementing classical QSAR and CATALYST based space-modeling approaches, it has been explored that attachment of aryl ring systems to unsaturated linkages, availability of phenolic hydroxyl group, global hydrophobicity, and stereochemistry of certain functional groups might be important for governing the subtype specific estrogenic behavior of this group of compounds. Supplementing this deduction, critical interfeature distances between hydrogen bond acceptor, hydrophobic, and ring aromatic features along with steric influence are found to primarily influence the ER-subtypes specific binding of this series of compounds. 相似文献
93.
In this article, we derive several properties such as marginal distribution, moments involving zonal polynomials, and asymptotic expansion of the complex bimatrix variate beta type 1 distribution introduced by D?´az-Garc?´a and Gutiérrez Jáimez [José A. D?´az-Garc?´a, Ramón Gutiérrez Jáimez, Complex bimatrix variate generalised beta distributions, Linear Algebra Appl. 432 (2010) 571-582]. We also derive distributions of several matrix valued functions of random matrices jointly distributed as complex bimatrix variate beta type 1. 相似文献
94.
Chandra S. Sharma Padam N. Nagar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1793-1798
Dialkyl(aryl) phosphoryl derivatives of alkylene dithiophosphates of general formula (S)SP(O)(OR) 2 : R = Pr i , Ph and G = ═CMe 2 CMe 2 ═, ═CH 2 CH 2 CHMe═, ═CH 2 CH 2 CH 2 CH 2 ═, ═CMe 2 CH 2 CHMe═, and ═CH 2 CMe 2 CH 2 ═; have been synthesized by reacting dialkyl and diaryl phosphoryl chloride with ammonium salts of alkylene dithiophosphates in 1:1 molar ratio in refluxing benzene. The products formed are yellow-colored viscous liquids and white-colored waxy solids; they are soluble in common organic solvents and are nonvolatile, even under reduced pressure. The new compounds have been characterized by elemental analysis, molecular weight measurements and spectroscopic (IR, 1 H NMR, and 31 P NMR)] data. 相似文献
95.
Using accurate numerical-relativity simulations of (nonspinning) black-hole binaries with mass ratios 1:1, 2:1, and 3:1, we compute the gauge-invariant relation between the (reduced) binding energy E and the (reduced) angular momentum j of the system. We show that the relation E(j) is an accurate diagnostic of the dynamics of a black-hole binary in a highly relativistic regime. By comparing the numerical-relativity E(NR)(j) curve with the predictions of several analytic approximation schemes, we find that, while the canonically defined, nonresummed post-Newtonian-expanded E(PN)(j) relation exhibits large and growing deviations from E(NR)(j), the prediction of the effective one body formalism, based purely on known analytical results (without any calibration to numerical relativity), agrees strikingly well with the numerical-relativity results. 相似文献
96.
Mukesh Kumar Atal Jyoti Jain Veena Dhayal Meena Nagar Rakesh Bohra Kuldeep S. Rathore Narendra S. Saxena 《Journal of Sol-Gel Science and Technology》2013,67(1):88-96
A glycol ether modified precursor, [Nb{O(CH2CH2O)2}(OPri)3] (A) was prepared by the reaction of Nb(OPri)5 with O(CH2CH2OH)2 in 1:1 molar ratio in anhydrous benzene. Further reactions of A with a variety of internally functionalized oximes in different molar ratios, yielded heteroleptic complexes of the type, [Nb{O(CH2CH2O)2}(OPri)3?n{ON = C(CH3)(Ar)}n] (1–9) {where Ar = C4H3O-2, n = 1 [1], n = 2 [2], n = 3 [3]; C4H3S-2, n = 1 [4], n = 2 [5], n = 3 [6]; C5H4N-2, n = 1 [7], n = 2 [8], n = 3 [9]}. All the above derivatives have been characterized by elemental analyses, FT-IR, NMR (1H, 13C {1H}) and FAB mass studies. Spectral studies of 1–9 suggest the presence of mono- and bi-dentate mode of oxime moieties, in the solution and in the solid states, respectively. FAB mass studies indicate monomeric nature for 3 and dimeric nature for A. TG curves of A and 6 show their low thermal stability. Soft transformation of A and 3 to pure niobia, a and b, respectively have been carried out by sol–gel technique. The XRD patterns of niobia a and b suggest the formation of nano-size crystallites of average size of 10.8 and 19.5 nm, respectively. The XRD patterns also indicate the formation of monoclinic phase of the niobia in both the cases. Absorption spectra of a and b suggest energy band gaps of 4.95 and 4.39 eV, respectively. 相似文献
97.
98.
Savan K. Raj Abhishek Rajput Hariom Gupta 《Journal of Dispersion Science and Technology》2019,40(2):250-255
Graphene quantum dots (GQDs) have been prepared from graphene oxide (GO) and characterized by standard analytical techniques. The size of the prepared GQDs ranges from 2-10?nm. Aqueous dispersion of GQDs exhibited excitation-dependent emission behavior. Emission intensity of the aqueous dispersion found stable for the examined duration of about four months. GQDs exhibited selective recognition of Fe3+ and Cr3+ out of various common ions such as alkali, alkaline-earth and transition metal ions in aqueous medium through fluorescence quenching. The lower limit of detection of Fe3+ is 1?µM and that of Cr3+ is 4?µM. 相似文献
99.
Renu Sharma Meena Nagar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1526-1535
A series of new mixed ligand complexes of Zn(II), Cd(II), and Hg(II) with citronellal thiosemicarbazone [3,7-dimethyl-6-octene-1-a1 thiosemicarbazone (LH)] and N-phthaloyl amino acids (AH) have been synthesized by the reaction of metal(II) chloride with ligands citronellal thiosemicarbazone (DOTSC) and N-phthaloyl glycine [1,3-dihydro-1,3-dioxo-2H-isoindole-2-acetic acid (A1H)] or N-phthaloyl alanine [1,3-dihydro-1,3-dioxo-α(methyl)-2H-isoindole-2-acetic acid (A2H)] in 1:1:1 molar ratio in dry refluxing ethanol. All the complexes have been characterized by elemental analyses, molar conductance measurement, molecular weight measurement, IR, and multinuclear NMR (1H and 13C{1H}) spectral studies. IR, 1H, and 13C{1H} NMR spectral studies suggest the involvement of azomethine-N, thiol-S atoms of the thiosemicarbazone moiety and both carboxylate-O of N-phthaloyl amino acid moiety in coordination with central metal(II) ion, and four coordinated geometries have been assigned to these complexes. The free ligands and metal complexes have been screened for their antifungal activity against two fungal strains, Fusarium moniliformae and Macrophomina phaseolina, using the the radial growth method. The results of antifungal activity show that metal complexes show enhanced higher activity than the free ligands. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
100.
Shahnawaz Iram Siddiqui Mangey Ram Nagar Abhijeet Choudhury Jin-Tin Lin Dovydas Blazevicius Gintare Krucaite Saulius Grigalevicius Jwo-Huei Jou 《Molecules (Basel, Switzerland)》2021,26(24)
Low color temperature candlelight organic light-emitting diodes (LEDs) are human and environmentally friendly because of the absence of blue emission that might suppress at night the secretion of melatonin and damage retina upon long exposure. Herein, we demonstrated a lighting device incorporating a phenoxazine-based host material, 3,3-bis(phenoxazin-10-ylmethyl)oxetane (BPMO), with the use of orange-red and yellow phosphorescent dyes to mimic candlelight. The resultant BPMO-based simple structured candlelight organic LED device permitted a maximum exposure limit of 57,700 s, much longer than did a candle (2750 s) or an incandescent bulb (1100 s) at 100 lx. The resulting device showed a color temperature of 1690 K, which is significantly much lower than that of oil lamps (1800 K), candles (1900 K), or incandescent bulbs (2500 K). The device showed a melatonin suppression sensitivity of 1.33%, upon exposure for 1.5 h at night, which is 66% and 88% less than the candle and incandescent bulb, respectively. Its maximum power efficacy is 23.1 lm/W, current efficacy 22.4 cd/A, and external quantum efficiency 10.2%, all much higher than the CBP-based devices. These results encourage a scalable synthesis of novel host materials to design and manufacture high-efficiency candlelight organic LEDs. 相似文献