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31.
Molybdenum (0.5 at%) doped indium oxide thin films deposited by spray pyrolysis technique were irradiated by 100 MeV O7+ ions with different fluences of 5×1011, 1×1012 and 1×1013 ions/cm2. Intensity of (222) peak of the pristine film was decreased with increase in the ion fluence. Films irradiated with the maximum ion fluence of 1×1013 ions/cm2 showed a fraction of amorphous nature. The surface microstructures on the surface of the film showed that increase in ion fluence decreases the grain size. Mobility of the pristine molybdenum doped indium oxide films was decreased from ~122 to 48 cm2/V s with increasing ion fluence. Among the irradiated films the film irradiated with the ion fluence of 5×1011 ions/cm2 showed relatively low resistivity of 6.7×10?4 Ω cm with the mobility of 75 cm2/V s. The average transmittance of the as-deposited IMO film is decreased from 89% to 81% due to irradiation with the fluence of 5×1011 ions/cm2.  相似文献   
32.
A novel approach for ATRP has been developed which enables the polymerization of vinyl monomers including those bearing carboxylic acid groups such as acrylic/methacrylic acid in the free acid form with ppm amounts of copper. The quantity of copper used in the polymerization is comparable to those left in purified polymers obtained by a conventional ATRP process.  相似文献   
33.
Abstract  A series of variously substituted N-methylpiperidin-4-one-O-benzyloximes were synthesized by three different methods. Among them, the direct conversion of 2,6-diarylpiperidin-4-ones into the corresponding oxime ethers (method A) was proved to be better than the other two methods in the sense of good yield, convenience, easy work-up and quick reaction time. All the synthesized compounds are characterized by IR, Mass and NMR (1H NMR, 13C NMR, 1H-1H COSY, 1H-13C COSY and HMBC) spectral studies. The conformational preference of the synthesized oxime ethers with/without alkyl and aryl substituents at C-3/C-5 and C-2/C-6 is discussed using the spectral data. The observed chemical shifts and coupling constants suggest that the synthesized oxime ethers adopt chair conformation with equatorial orientation of all the substituents, whereas 1-methyl-3-isopropyl-2,6-diphenylpiperidin-4-one-O-benzyloxime also exists in boat conformation. Based on the NMR data, the effects of oximination on ring carbons and their associated protons and alkyl substituents are discussed. In addition, the effect of NMe group on the 2,6-diarylpiperidin-4-one-O-benzyloximes was also studied. Graphical abstract     相似文献   
34.
Solution-processed nickel oxide (s-NiOx) was synthesized for use as hole-transport layers (HTLs) in the fabrication of polymer solar cell (PSC) devices. The s-NiOx thin-films were deposited using spin-coating and post-annealed at 300 °C, 400 °C, or 500 °C. With increased annealing temperature, the nickel acetate precursor decomposes more fully and forms s-NiOx films that show larger crystalline grain sizes with lower root mean square surface roughness. Bulk heterojunction solar cells fabricated with the new random polymer RP(BDT-PDBT) and [6,6]-phenyl-C70-butyric acid methyl ester (PC70BM) using s-NiOx as HTLs exhibit a 4.46% enhancement in power conversion efficiency and better stability compared to conventional PSCs using poly (3,4-ethylenedioxythiophene):poly(styrene sulfonate) as HTLs. We believe that the solution-processable and highly stable s-NiOx could be a potential alternative for functional interface materials in optoelectronic devices.  相似文献   
35.
A highly flexible algorithm for interferogram processing which enables the operator to interact with the computer at every stage, is presented. This algorithm developed on a PDP 11/23 microcomputer, uses Fortran callable subroutines based on Intellect 100 image processing hardware and a CUB R-G-B monitor. It also uses a single frame buffer of 512 x 512 x 8 pixels.This software employs a pseudo-colour mapping technique which helps the operator to select the optimum threshold values. Manual editing of the processed fringe pattern is also possible to enable removal of unwanted kinks and to connect any discontinuities. A fringe scanning subroutine is used to number the fringes and to store the peak coordinates in a data file for fringe analysis.The algorithm is employed for the analysis of an interferogram obtained from an inverting interferometer and the results are presented.  相似文献   
36.
A series of 2,6-diarylpiperidin-4-ones having electron withdrawing chloroacetyl group at the heterocyclic nitrogen were synthesized. Unambiguous characterizations of the synthesized compounds were achieved by one-dimensional ((1)H NMR and (13)C NMR) and two-dimensional (HOMOCOSY, NOESY and HSQC spectra for compounds 8 and 9 and HOMOCOSY spectrum only for 10) NMR spectroscopic data. The conformational preferences of N-chloroacetyl-2,6-diarylpiperidin-4-ones with and without alkyl substituent at C-3 and C-5 (8-14) have also been discussed using the spectral studies. The spectral data and extracted coupling constant values suggest that the compounds 8, 12 and 14 adopt flattened boat conformation whereas the remaining compounds exist in twist-boat conformations in solution with coplanar orientation of the chloroacetyl moiety present at the heterocyclic nitrogen. The substituent parameters for the chloroacetyl moiety on the heterocyclic ring carbons have also been derived and discussed elaborately on the basis of their steric, electronic and gamma-eclipsing interaction. This substituent at the nitrogen causes a substantial change on the chemical shifts of ring carbons and the associated protons.  相似文献   
37.
The influence of heteroaromatic N-base (1,10-phenanthroline) (Phen), a new additive as complexing agent on tris(thiourea)zinc(II)sulphate (ZTS) crystals from aqueous solutions at 30 °C is investigated. Crystals were grown using low concentration of the dopant (0.005 M L?1) in the aqueous growth medium and the growth promoting effect (GPE) is much greater because of an increase in the metastable zone width. High dopant concentration decreases GPE. The crystalline perfection of the grown crystals is quite good both in doped and undoped crystals as evaluated by high-resolution X-ray diffractometry (HRXRD). The diffraction curve of a typical Phen doped as-grown ZTS crystal was observed to contain a single peak indicating that the crystal does not contain any epitaxial layer on the surface or internal structural grain boundaries. Not much variation is observed in FT-IR and XRD of pure and doped ZTS. Phen depresses the NLO efficiency of ZTS. It could be ascribed due to the disturbance of charge transfer in the presence of the dopant. The grown crystals were also characterized by UV–Vis, SEM and TG–DTA techniques.  相似文献   
38.
The influence of doping the transition metal Zn(II) on potassium hydrogen phthalate (KHP) crystals has been studied. A close observation of FT-IR and XRD profiles of doped and undoped samples reveals some minor structural variations. It appears that the crystal undergoes considerable lattice stress as a result of doping the bivalent zinc. Furthermore, the possibility of cation vacancies aroused owing to the substitution of K1+ by Zn2+ could result in a defective crystal system. Energy dispersive spectra reveal the incorporation of Zn(II) in the crystalline matrix of KHP crystals. Differential scanning calorimetry (DSC) and TG-DTA studies reveal the purity of the sample and no decomposition is observed below the melting point. Small quantity additions of Zn(II) enhance the fluorescence intensity of KHP crystals. The doping results in morphological changes and significantly improves the second harmonic generation (SHG) efficiency of the host crystal.  相似文献   
39.

Abstract  

A series of differently substituted 2,4-diaryl-3-azabicyclo[3.3.1]nonan-9-one oximes have been synthesized and their 1H and 13C NMR chemical shifts have been unambiguously assigned using H,H-COSY, NOESY, HSQC, and HMBC spectral data. On the basis of the NMR studies, irrespective of the nature and position of the substituents, all reported compounds exist in twin-chair conformation with equatorial disposition of the phenyl groups at C-2 and C-4 of the 3-azabicyclononane moiety. Among the synthesized oxime derivatives, compounds with halo-substituents at ortho/para positions of the phenyl showed good antifungal profile against all tested organisms.  相似文献   
40.

Abstract  

A new mixed crystal K1−x(NH4)xH2PO4 (KADP) of ammonium dihydrogen phosphate (ADP) of ADP–KCl system has been synthesized with x = 0.5 by slow evaporation of the mixture of equimolar aqueous solution at room temperature. Crystal composition determined by single crystal X-ray diffraction analysis reveals that it belongs to the tetragonal system with noncentrosymmetric space group I-42d and it is structurally similar to ADP crystals with the following parameters: a = 7.418(3) ?; c = 7.2284(6) ?; v = 404.63(4) ?3; z = 4. The substitution results in defect centers which influence the physical properties. Mixed crystal has a superior NLO activity, twice that of KH2PO4 (KDP), a well known NLO material and the enhanced NLO activity is rationalized. The structural analysis of KADP and the influence of partial cationic substitution in ADP by K+ ions on the NLO properties are reported.  相似文献   
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