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61.
The spectra of P16O and P18O were excited in sealed discharge tubes containing neon (2–3 mm. pressure), oxygen gas enriched to 65 per cent. of18O and trace amounts of phosphorus vapour and photographed on a 3 m. grating spectrograph at a dispersion of 2·5 Å/mm. Isotope shift studies in theβ-bands confirmed the earlier vibrational scheme of Curryet al. and showed conclusively that the red as well as the violet degraded bands belonged to the sameβ-system. The present studies of isotope shifts also confirmed the vibrational assignments of the extensive ultraviolet bands involving the2 Σ ??X2 Π transition and theγ-bands (A2 Σ +?X2 Π). In the case of the visible bands, they provided evidence for the first time that the bands at 5585 Å, 5962 Å and 6385 Å belonged to one system and involved 0–0, 0–1 and 0–2 transitions respectively. 相似文献
62.
Shih PI Chiang CL Dixit AK Chen CK Yuan MC Lee RY Chen CT Diau EW Shu CF 《Organic letters》2006,8(13):2799-2802
[reaction: see text] A series of carbazole/fluorene (CBZm-Fn) hybrids were effectively synthesized through Friedel-Crafts-type substitution of the carbazole rings. These compounds were thermally and morphologically stable host materials for OLED applications. Efficient blue phosphorescent OLEDs were obtained when employing CBZ1-F2 as the host and FIrpic as the guest. 相似文献
63.
64.
Abstract The experimental observables of a vibrational spectrum are depicted either in the form of their positions, i.e., frequency relating the energy required in a given quantum transition, or as the intensities of absorption and scattering related to their transition probabilities. Expressed in terms of molecular parameters, the frequencies depend on the geometry, atomic masses, and intramolecular forces [11 while the band intensities [2] reflect changes in dipole moment (infrared) or polarizabilities (Raman) which are caused during a vibrational displacement and are related to movement of electronic charges within the individual bonds. The mathematical basis for determining vibrational frequencies was well established as early as 1940 by Wilson [3] and others [4, 51. Applying the interpretation of vibrational spectra has become routine in the multitudinous disciplines of chemical literature [6–26]. Accounts of infrared and Raman spectra [27–29], collection of literature [30], and reasonable sets of intramolecular forces [31, 321 are now available for the prediction of normal frequencies of hydrocarbons. 相似文献
65.
Abstract During recent years the study of the vibrational structure of catalysts by laser Raman spectroscopy (LRS) and of the interfacial properties of adsorbed species on solid surfaces by resonance Raman spectroscopy (RRS) and surface-enhanced Raman spectroscopy (SERS) have comprised one of the major research activities in the area of Raman spectroscopy [1–10] as applied to catalysts [11, 12]. 相似文献
66.
Mahesh B. Muluk Sambhaji T. Dhumal Pramod S. Phatak Naziya N. M. A. Rehman Prashant P. Dixit Prafulla B. Choudhari Ramrao A. Mane Kishan P. Haval 《Journal of heterocyclic chemistry》2019,56(9):2411-2418
In the present study, substituted formylnaphthalenyloxymethyl‐triazolyl‐N‐phenylacetamide derivatives ( 6a – k ) have been designed and synthesized employing click chemistry approach and evaluated for their in vitro antifungal and antibacterial activities. All the newly synthesized compounds were thoroughly characterized by 1H NMR, 13C NMR, and HRMS spectral techniques. Among the screened compounds, 6d , 6e , 6j , and 6k have shown good antifungal and antibacterial activities. Compound 6k has shown very effective antimicrobial activity. We further performed exploratory docking studies on microbial DNA gyrase to rationalize the in vitro biological data and to demonstrate the mechanism of antimicrobial activity. This is the first report to demonstrate the formylnaphthalenyloxymethyl, triazole, and N‐phenylacetamide hybrids as potential antimicrobial agents. 相似文献
67.
68.
Kamlesh Pandey Mrigank Mauli Dwivedi Mridula Tripathi Markandey Singh S. L. Agrawal 《Ionics》2008,14(6):515-523
Development and characterisation of polyethylene oxide (PEO)-based nanocomposite polymer electrolytes comprising of (PEO-SiO2): NH4SCN is reported. For synthesis of the said electrolyte, polyethylene oxide has been taken as polymer host and NH4SCN as an ionic charge supplier. Sol–gel-derived silica powder of nano dimension has been used as ceramic filler for development
of nanocomposite electrolytes. The maximum conductivity of electrolyte ∼2.0 × 10−6 S/cm is observed for samples containing 30 wt.% silica. The temperature dependence of conductivity seems to follow an Arrhenius-type,
thermally activated process over a limited temperature range. 相似文献
69.
Dr. Swati Deswal Rishukumar Panday Dr. Dipti R. Naphade Prashant Dixit Dr. Balu Praveenkumar Dr. Jan K. Zaręba Prof. Dr. Thomas D. Anthopoulos Prof. Dr. Satishchandra Ogale Prof. Dr. Ramamoorthy Boomishankar 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(33):e202200751
Bismuth containing hybrid molecular ferroelectrics are receiving tremendous attention in recent years owing to their stable and non-toxic composition. However, these perovskite-like structures are primarily limited to ammonium cations. Herein, we report a new phosphonium based discrete perovskite-like hybrid ferroelectric with a formula [Me(Ph)3P]3[Bi2Br9] ( MTPBB ) and its mechanical energy harvesting capability. The Polarization-Electric field (P-E) measurements resulted in a well-defined ferroelectric hysteresis loop with a remnant polarization value of 2.1 μC cm−2. Piezoresponse force microscopy experiments enabled visualization of the ferroelectric domain structure and evaluation of the piezoelectric strain coefficient (d33) for an MTPBB single crystal and thin film sample. Furthermore, flexible devices incorporating MTPBB in polydimethylsiloxane (PDMS) matrix at various concentrations were fabricated and explored for their mechanical energy harvesting properties. The champion device with 20 wt % of MTPBB in PDMS rendered a maximum peak-to-peak open-circuit voltage of 22.9 V and a maximum power density of 7 μW cm−2 at an optimal load of 4 MΩ. Moreover, the potential of MTPBB -based devices in low power electronics was demonstrated by storing the harvested energy in various electrolytic capacitors. 相似文献
70.
Vinay Kiran Narayanan Balaji Bhavesh Babulal Gabani Manjuanth Bajantri Rajesh Chandran Abhishek Dixit Nuggehally R. Srinivas Ramesh Mullangi 《Biomedical chromatography : BMC》2020,34(9):e4879
We developed and validated a simple, sensitive, selective, and reliable LC–MS/MS–ESI method for the direct quantitation of lumefantrine (LFN) enantiomers [(−)-LFN and (+)-LFN] in mice plasma as per regulatory guideline. LFN enantiomers and carbamazepine (internal standard) were extracted from mice plasma using Strata X SPE (solid-phase extraction) cartridges. Good resolution between enantiomers was achieved on a Chiralpak IA-3 column using an isocratic mobile phase (0.1% of diethyl amine in methanol), which was delivered at a flow rate of 0.8 mL/min. Detection and quantitation were performed using multiple reaction monitoring mode following the transitions m/z 530.27 → 512.30 and 237.00 → 194.00 for LFN enantiomers and the internal standard, respectively, in the positive-ionization mode. The proposed method provided accurate and reproducible results over the linearity range of 2.39–895 ng/mL for each enantiomer. The intra- and inter-day precisions were in the range of 1.03–6.14 and 6.36–8.70 and 2.03–4.88 and 5.82–11.5 for (−)-LFN and (+)-LFN, respectively. Both (−)-LFN and (+)-LFN were found to be stable under different stability conditions. The method was successfully used to delineate stereoselective pharmacokinetics of LFN enantiomers in mice after an oral administration of rac-LFN (20 mg/kg). The pharmacokinetic results indicated that the disposition of LFN enantiomers was stereoselective in mice. 相似文献