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971.
An explicit construction of all the homogeneous holomorphic Hermitian vector bundles over the unit disc D is given. It is shown that every such vector bundle is a direct sum of irreducible ones. Among these irreducible homogeneous holomorphic Hermitian vector bundles over D, the ones corresponding to operators in the Cowen–Douglas class Bn(D) are identified. The classification of homogeneous operators in Bn(D) is completed using an explicit realization of these operators. We also show how the homogeneous operators in Bn(D) split into similarity classes. 相似文献
972.
Sharma SK Misra AK Clegg SM Barefield JE Wiens RC Acosta TE Bates DE 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,80(1):75-81
The authors have utilized a recently developed compact Raman spectrometer equipped with an 85 mm focal length (f/1.8) Nikon camera lens and a custom mini-ICCD detector at the University of Hawaii for measuring remote Raman spectra of minerals under supercritical CO(2) (Venus chamber, ~102 atm pressure and 423 K) excited with a pulsed 532 nm laser beam of 6 mJ/pulse and 10 Hz. These experiments demonstrate that by focusing a frequency-doubled 532 nm Nd:YAG pulsed laser beam with a 10× beam expander to a 1mm spot on minerals located at 2m inside a Venus chamber, it is possible to measure the remote Raman spectra of anhydrous sulfates, carbonates, and silicate minerals relevant to Venus exploration during daytime or nighttime with 10s integration time. The remote Raman spectra of gypsum, anhydrite, barite, dolomite and siderite contain fingerprint Raman lines along with the Fermi resonance doublet of CO(2). Raman spectra of gypsum revealed dehydration of the mineral with time under supercritical CO(2) at 423 K. Fingerprint Raman lines of olivine, diopside, wollastonite and α-quartz can easily be identified in the spectra of these respective minerals under supercritical CO(2). The results of the present study show that time-resolved remote Raman spectroscopy with a compact Raman spectrometer of moderate resolution equipped with a gated intensified CCD detector and low power laser source could be a potential tool for exploring Venus surface mineralogy both during daytime and nighttime from a lander. 相似文献
973.
Singh Pavitra Kalita Pankaj Mahanta Pinakeswar 《Journal of Thermal Analysis and Calorimetry》2020,141(6):2647-2656
Journal of Thermal Analysis and Calorimetry - A rotating fluidized bed in static geometry (RFB-SG) without slits is presented in this paper as a research objective. The concept of RFB-SG is highly... 相似文献
974.
Sadia Baig Pankaj Kumar Jenner Ngai Prof. Yuning Li Dr. Safeer Ahmed 《Chemphyschem》2020,21(9):895-907
This work reports development of yttrium doped copper oxide (Y−CuO) as a new hole transport material with supplemented optoelectronic character. The pure and Y-doped CuO thin films are developed through a solid-state method at 200 °C and recognized as high performance p-channel inorganic thin-film transistors (TFTs). CuO is formed by oxidative decomposition of copper acetylacetonate, yielding 100 nm thick and conductive (40.9 S cm−1) compact films with a band gap of 2.47 eV and charge carrier density of ∼1.44×1019 cm−3. Yttrium doping generates denser films, Cu2Y2O5 phase in the lattice, with a wide band gap of 2.63 eV. The electrical conductivity increases nine-fold on 2 % Y addition to CuO, and the carrier density increases to 2.97×1021 cm−3, the highest reported so far. The TFT devices perform remarkably with high field-effect mobility (μsat) of 3.45 cm2 V−1 s−1 and 5.3 cm2 V−1 s−1, and considerably high current-on/off ratios of 0.11×104 and 9.21×104, for CuO and Y−CuO films, respectively (at −1 V operating voltage). A very small width hysteresis, 0.01 V for CuO and 1.92 V for 1 % Y−CuO, depict good bias stability. Both the devices work in enhancement mode with stable output characteristics for multiple forward sweeps (5 to −60 V) at −1Vg. 相似文献
975.
Connor E. Rahm Fernando Torres‐Canas Pankaj Gupta Philippe Poulin Noe T. Alvarez 《Electroanalysis》2020,32(7):1533-1545
Electroanalytical methods can be used for the reliable detection of the toxic heavy metal lead in drinking water samples. Inkjet printed electrodes have potential for the rapid and affordable assessment of drinking water. Researchers have shown the electrochemical sensing applicability of inkjet printed electrodes. In this work, Pb2+ was detected using an inkjet printed multi‐walled carbon nanotube (IJP‐MW‐CNT) electrode with silver tracks printed underneath. The silver tracks provide the sensor with the conductivity needed for sensitive measurements. MW‐CNT were dispersed in water using bile salts as a surfactant to prepare the ink. The IJP‐MW‐CNT electrode was used as the working electrode with a platinum wire and Ag/AgCl as auxiliary and reference electrode, respectively. The electrodes performance was optimized in 0.1 M acetate buffer (pH=4.3) and had two linear ranges of 5 to 20 ppb (R2=0.99) with a sensitivity of 38 nA/ppb and 20 to 50 ppb (R2=0.98) with a sensitivity of 15 nA/ppb and a limit of detection (LOD) of 1.0 ppb for Pb2+. The analytical applicability of electrode was determined by constructing a calibration curve in an unaltered drinking water sample (i. e.) Cincinnati tap water with two linear ranges of 15 to 40 ppb (R2=0.99) with a sensitivity of 1.5 nA/ppb and 40 to 70 ppb (R2=0.99) with a sensitivity of 3.5 nA/ppb and a LOD of 1.0 ppb for Pb2+. Effects of copper and cadmium as potential interferents are reported. 相似文献
976.
Apoorva Misra Jaya Dwivedi Shruti Shukla Dharma Kishore Swapnil Sharma 《Journal of heterocyclic chemistry》2020,57(4):1545-1558
Novel quinazoline embellished analogues of 1,5-benzodiazepine ( 6, 9, 13, 17, 21 and 24 ) were synthesized using one-pot domino approach. Structure of the compounds synthesized, were established with the help of IR, 1H NMR, 13C NMR and mass spectral data. Further, antibacterial activity, FE-SEM imaging and cell leakage study was also performed. 相似文献
977.
Dr. Yingguo Liu Pankaj Kumar Majhi Runjiang Song Dr. Chengli Mou Dr. Lin Hao Prof. Huifang Chai Prof. Zhichao Jin Prof. Yonggui Robin Chi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(10):3887-3891
A catalytic dynamic kinetic resolution and asymmetric acylation reaction of hydroxyphthalides is developed. The reaction involves formation of a carbene catalyst derived chiral acyl azolium intermediate that effectively differentiates the two enantiomers of racemic hydroxyphthalides. The method allows quick access to enantiomerically enriched phthalidyl esters with proven applications in medicine. It also enables asymmetric modification of natural products and other functional molecules that contain acetal/ketal groups, such as corollosporine and fimbricalyxlactone C. 相似文献
978.
Tavarekere K. Chandrashekar Sundararaman Venkatraman Viswanathan Prabhuraja Rajneesh Misra Viswanathan Baskar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):845-872
Abstract Various supramolecular assemblies based on expanded porphyrins building blocks containing sulfur and/or selenium in the core, formed through multiple non-covalent hydrogen bonding interactions are highlighted. Specifically, modified expanded porphyrins such as 22 π sapphyrins, 26 π rubyrins, and 34 π octaphyrins self assemble in solid state through C–H…O, C–H…N, C–H…S, C–H…Se, C–H…π, and C–H…Cl interactions to form dimeric, oligomeric, and three dimensional networks. Furthermore, the supramolecular networks promoted by trapped solvent molecules such as nitrobenzene and bound anions such as chloride or trifluoroacetate through noncovalent interactions will be discussed. 相似文献
979.
The aqueous polymerization of acrylamide initiated by the glycolic acid/Ce4+ redox system was studied in sulfuric acid medium at 35 ± 0.2°C under a nitrogen atmosphere. The initiation was carried out by the free radical generated in the decomposition of the complex formed between the oxidant and the reductant. The monomer disappearance was found to be proportional to [GA]0,89[Ce4+]0.57[M]1.0, and the rate of ceric ion disappearance was found to be directly proportional to [Ce4+] and [GA] but independent of [M]. The activation energy of the system was found to be 7.21 kcal/deg/mol. The molecular weight of polyacrylamide increased with increasing [monomer] and decreased with increasing [catalyst]. The effect of pH was also studied in the pH range 2.22 to 1.44. 相似文献
980.