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91.
A. V. Kulkarni Ram Lal S. M. Kanetkar S. M. Chaudhari S. V. Ghaisas 《辐射效应与固体损伤》2013,168(2-4):139-145
The changes occurring upon pulsed laser irradiation on maraging steel of 69Fe-18Ni-8Co-5Mo composition have been studied using Conversion Electron Mossbauer Spectroscopy (CEMS), Scanning Electron Microscopy (SEM), Internal Friction (IF) and aqueous corrosion. It is observed that an austenitic phase in the upper layer is retained without much change in chemical composition for the pulsed laser treated sample. Mechanical bulk properties are not affected by this treatment, however betterment in corrosion resistance is achieved. 相似文献
92.
Jia G Takayama Y Flanigan DC Kaeding CC Zhou J Chaudhari A Clark D Sammet S Liang J Choi S Knopp MV 《Magnetic resonance imaging》2011,29(3):335-341
Purpose
To establish the feasibility of chemical exchange saturation transfer (proteinCEST) MRI in the differentiation of osteoarthritis (OA) knee joints from non-OA joints by detecting mobile protein and peptide levels in synovial fluid by determining their relative distribution.Materials and Methods
A total of 25 knees in 11 men and 12 women with knee injuries were imaged using whole knee joint proteinCEST MRI sequence at 3 T. The joint synovial fluid was segmented and the asymmetric magnetization transfer ratio at 3.5 ppm MTRasym (3.5 ppm) was calculated to assess protein content in the synovial fluid. The 85th percentile of synovial fluid MTRasym (3.5 ppm) distribution profile was compared using the independent Student's t test. The diagnostic performance of the 85th percentile of synovial fluid MTRasym (3.5 ppm) in differentiating OA and non-OA knee joints was evaluated.Results
The 85th percentile of synovial fluid MTRasym (3.5 ppm) in knee joints with OA was 8.6%±3.4% and significantly higher than that in the knee joints without OA (6.3%±1.4%, P<.05). A knee joint with an 85th percentile of synovial fluid MTRasym (3.5 ppm) greater than 7.7% was considered to be an OA knee joint. With the threshold, the sensitivity, specificity and overall accuracy for differentiating knee joints with OA from the joints without OA were 54% (7/13), 92% (11/12) and 72% (18/25), respectively.Conclusion
proteinCEST MRI appears feasible as a quantitative methodology to determine mobile protein levels in synovial fluid and identify patterns characteristic for OA disease. 相似文献93.
Vijayanand Kalamse Nitin Wadnerkar Ajay Chaudhari 《International journal of quantum chemistry》2011,111(9):2014-2020
The 5d‐metal (excluding La) monofluorides were studied using second order Moller‐Plesset (MP2) perturbation theory. The basis set used was Stuttgart/Dresden (SDD) effective core potentials (ECPs). The ground state multiplicity for these dimers was obtained. The cation and anion of these dimers were also studied at the same level of theory. Relative stability, atomic charges, electron affinity, ionization potential, binding energy (BE), vibrational frequencies, and electronic configuration for these dimers were also obtained. The properties of the neutral dimers were compared with those of their anion and cation. The electronic states of each neutral dimer as well as its ions at their ground state were also defined. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 相似文献
94.
A systematic exploration of thiophilic ability of o-iodoxybenzoic acid (IBX) for oxidative desulfurization to trigger domino reactions leading to new methodologies for synthesis of different azoles is described. A variety of highly substituted oxadiazoles, thiadiazoles, triazoles, and tetrazoles have been successfully synthesized in good to excellent yields, starting from readily accessible thiosemicarbazides, bis-diarylthiourea, 1,3-disubtituted thiourea, and thioamides. 相似文献
95.
We report electron impact total ionisation cross sections for phosphorous (P), arsenic (As), diphosphorous (P2), diarsenic (As2), tetra phosphorous (P4) and tetra arsenic (As4) from the threshold of the target to 2000 eV. We employed spherical complex optical potential to compute total inelastic cross sections (Qinel). The total ionisation cross section is extracted from the total inelastic cross section using the complex scattering potential–ionisation contribution method. The results of most of the targets studied here compare well with the measurements and the theoretical data wherever available. The correlation between the peak of ionisation cross sections with the number of target electrons and polarisability is also reported. It is observed that the maximum ionisation cross sections depend linearly on the number of target electrons and polarisability of the target. This linear correlation is used to predict the maximum ionisation cross sections for the targets (I2, HI and PF3) where no experimental data are available. 相似文献
96.
Breast tumor vascularity identified by contrast enhanced ultrasound and pathology: initial results 总被引:10,自引:0,他引:10
Chaudhari MH Forsberg F Voodarla A Saikali FN Goonewardene S Needleman L Finkel GC Goldberg BB 《Ultrasonics》2000,38(1-8):105-109
Quantifiable measures of vascularity obtained from contrast enhanced color flow images were correlated with pathologic vascularity measurements in ten female patients with a solid breast mass. Each patient received Levovist Injection (Berlex Laboratories Inc., Montville, NJ). Color flow images pre- and post-contrast were obtained using an HDI 3000 unit (ATL, Bothell, WA) before removing the mass for pathologic vascularity assessments. Image-processing techniques were used to obtain both the ultrasound and pathologic vascularity measurements. Multiple linear regression found significant correlations for ultrasonic vascularity measurements post contrast and pathology (P = 0.02 and 0.06). No correlations were found between pre-contrast ultrasound and pathology. In conclusion, post-contrast ultrasonic flow measures provide a non-invasive measure of breast tumor neovascularity. However, the patient population is small, and until further patients are analyzed, these conclusions are preliminary. 相似文献
97.
Photoconductivity experiment has been performed on high resistivity () 3As2Se32Sb2Se3 amorphous films in the temperature range from 278°K to 308°K, as a function of light intensity, I0. The results are that at intermediate light levels the photocurrent varies as I00.7 and at high light levels the photocurrent is directly proportional to I0. A simple recombination and trapping model is developed to interpret the observed photoconductivity data. From the temperature dependence of the photocurrent, an effective trap level located 0.3 eV below the band edge is deduced. 相似文献
98.
S. P. Ramnani C. V. Chaudhari N. D. Patil S. Sabharwal 《Journal of polymer science. Part A, Polymer chemistry》2004,42(15):3897-3909
Synthesis of crosslinked chitosan using γ irradiation in the presence of carbon tetrachloride as a sensitizer is carried out. The resultant crosslinked product, which is yellow in color, is characterized by elemental analysis, which shows the presence of chlorine. Crosslinked chitosan on hydrolysis with alkali results in the formation of another product that retains the crosslinked structure but does not have chlorine in it. Gel formatting characteristics of both these products have been studied. The crosslinked chitosan and its hydrolysis product are further characterized by various physical methods such as X‐ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR), and thermogravimetry. Based on the results, a probable mechanism of crosslinking whereby chitosan chains are crosslinked by a >CCl2 group is suggested. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3897–3909, 2004 相似文献
99.
S. V. Ghaisas K. Santosh George S. M. Chaudhari S. B. Ogale D. M. Phase V. G. Bhide 《Hyperfine Interactions》1987,35(1-4):663-666
The high temperature oxidation behavior of Fe50Ni50 alloy foils implanted with 100 KeV N2 + ions at a different dose values is studied by using the technique of conversion electron Mössbauer spectroscopy (CEMS). It has been shown that the implanted foils exhibit considerable adherence of scales and higher oxidation resistance as compared to the virgin foils. This excessive adherence of scales to the surface and higher resistance to oxidation of implanted samples is attributed to nickel enrichment in the surface layers. Various oxides of Fe, Ni and Fe?Ni are identified from the hyperfine interaction parameters of the corresponding CEMS spectra and also from x-ray diffraction measurements. 相似文献
100.
A nonisothermal adsorption experiment using a controlled flow of cyclopentane in the 333-313 K range is used to simultaneously estimate the specific surface area and micropore volume of a hybrid (organic/inorganic) alcogel. For reference, the method is also applied to an all-inorganic material with a more rigid structure, namely, a high surface area SiO(2)-Al(2)O(3). The proposed data analysis provides guidelines to determine whether adsorption data on a certain adsorbate/adsorbent system can be modeled effectively as a convolution of BET (meso- and macropore) and Dubinin-Radushkevitch (DR, micropore) contributions. Copyright 2000 Academic Press. 相似文献