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91.
Nirupama Singh Surbhi Choudhary Sumant Upadhyay Vibha R. Satsangi Sahab Dass Rohit Shrivastav 《Journal of Solid State Electrochemistry》2014,18(2):523-533
Nanocrystalline Zn1???x Ag x O y (x?=?10??3???50?×?10??3) thin films evolved through electrodeposition over ITO substrate have been investigated for photoelectrochemical splitting of water. Samples were characterized by XRD, EDX, SEM, AFM, UV–visible optical absorption, and Mössbauer spectral analysis. Ag incorporation led to a decrease in the band gap energy and alterations in microstructural and semiconductor properties. Raising Ag concentration in samples up to 1 % at. caused a significant reduction in density and electrical resistivity, enhanced absorption along with red shift to the band gap energy, anodic shift in flat band potential, and increased charge carrier density, enabling 1 % at. Ag-incorporated ZnO films most photosensitive by yielding highest short-circuit current, photocurrent density, and applied bias photon to current efficiency. Plausible reasons have been offered. 相似文献
92.
J. Manjunath Swamy Narendra Kamath Anil Kumar Radha Shekar Nuggehally R. Srinivas Fjalar Kristjansson 《Biomedical chromatography : BMC》2010,24(5):528-534
Sensitivity enhancement via summation of multiple MRM transition pairs is gaining popularity in tandem mass spectrometric assays. Numerous validation experiments describing the assays for two model substrates, clopidogrel and ramiprilat, were performed. The quantitation of clopidogrel was achieved by the summation of transition pairs m/z 322.2 to m/z 212.0 and m/z 322.2 to m/z 184.0, while that of ramiprilat was achieved by the summation of transition pairs m/z 389.2 to m/z 206.1 and m/z 389.2 to m/z156.1. The use of summation approach achieved sensitivities of >2 fold for both compounds as compared with the reported single MRM transition pair assays. The validation experiments addressed some important assay development issues, such as: (a) lack of impact of matrix effect; (b) unequivocal verification of the percentage contribution of each MRM transition pair towards sensitivity; (c) sensitivity enhancement factor achieved by summation approach of MRM transition pairs; and (d) accurate prediction of quality control samples using summation approach vs a single MRM transition pair. In summary, the appropriateness of using two MRM transition pairs for quantitation was demonstrated for both clopidogrel and ramiprilat. Additionally, pharmacokinetic application of the MRM transition pair assays using a summation approach was established for the two compounds. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
93.
To exploit the parallelism of optics in data processing,a suitable number system and an efficient encoding/decoding scheme for handling the data are very essential.In the field of optical computing and parallel information processing,several number systems like binary,quaternary,octal,hexadecimal,etc.have been used for different arithmetic and algebraic operations.Here,we have proposed an all-optical conversion scheme from its binary to its other 2n radix based form with the help of terahertz optical asymmetric demultiplexer (TOAD) based tree-net architecture. 相似文献
94.
The resolution for the three homologues of alpha-hydroxycarboxylic acids viz. lactic acid, alpha-hydroxyisobutyric acid (alpha-HIBA) and alpha-hydroxy-alpha-methylbutyric acid (alpha-H-alpha-MBA), was compared for the individual separation of 14 lanthanide elements under identical experimental conditions. Alpha-HIBA was found to be the best for separation of heavier lanthanides (Tb to Lu) while alpha-H-alpha-MBA led to a better separation for lighter lanthanides (La to Eu). All the 14 lanthanides were separated by gradient HPLC employing both alpha-HIBA and alpha-H-alpha-MBA so that there was reasonable resolution among all the peaks and the separation was completed in a short time. 相似文献
95.
Bernas A Kumar N Mäki-Arvela P Laine E Holmbom B Salmi T Murzin DY 《Chemical communications (Cambridge, England)》2002,(10):1142-1143
Development of a new heterogeneous catalytic pathway for isomerization of linoleic acid to conjugated linoleic acids at mild reaction conditions over Ni/H-MCM-41 in a soluted system. 相似文献
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97.
Kuzmann E. Nath A. Chechersky V. Li S. Wei Y. Chen X. Li J. Homonnay Z. Gál M. Garg V. K. Klencsár Z. Vértes A. 《Hyperfine Interactions》2002,139(1-4):631-639
57Fe transmission Mössbauer spectroscopy and X-ray diffractometry were used to study - and -polymorphs of iron phthalocyanines (FePc) to get information about their oxygenation in connection with controlled pyrolysis of flat layered phthalocyanines initiated by radicals at relatively low temperatures, to form acicular carbide particles encaged in carbon. Mössbauer spectroscopy and XRD revealed that the oxygenation of both - and -polymorphs of FePc was successfully achieved. New Mössbauer spectral components (doublets) appeared upon the oxygenation in both and FePc. This can be attributed to iron microenvironments containing oxygen between the layers of iron phthalocyanines. 相似文献
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