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21.
The cocaine analogue RTI-121 (3 beta-(4-iodophenyl)tropane-2 beta-carboxylic acid isopropyl ester), when labeled with carbon-11, was evaluated in rats as a potential PET ligand for the dopamine transporter. The compound gave in vivo striatum:cerebellum ratios that were similar to those obtained with the related ligand [11C]RTI-55 (2 beta-(4-iodophenyl)tropane-2 beta-carboxylic acid methyl ester) but showed a much greater selectivity for the dopamine compared with the 5-HT uptake site. The results indicate that [11C]RTI-121 could be used in preference to [11C]RTI-55 in man. Experimentally, [11C]RTI-121 has potential in the quantification of dopamine terminal function in rat models of disease, using a combination of autoradiography, postmortem sampling, and in vivo tomography.  相似文献   
22.
Thermal current converters or thermal transfer standard with AC–DC current shunts act as the reference standards for accurate and precise measurements of low frequency current in the frequency range from 40 Hz to 10 kHz. At present CSIR-NPL, India has the AC–DC current transfer difference (δ x) calibration facility upto 20 A. To extend our AC current calibration range from 20 A to 100 A, a current Tee for AC high current using LC connectors has been indigenously designed and developed. This paper presents the development of current Tee for AC high current calibration. The calibration results for assigning ‘δ x’ at 30 A current shunt with respect to 20 A are shown and the same measurement technique has been used to extend the current range up to 100 A.  相似文献   
23.
In a case of relapsing polychondritis it was possible to aspirate a collection of subcutaneous fluid from the patient's involved ear. A determination of total hemolytic complement activity of this fluid was low, suggesting that activation of the complement system may have occurred in the course of the patient's disease and might be related to the pathogenesis of this disorder.  相似文献   
24.
The present study seeks to develop a decision framework of enabler to help managers in offshore outsourcing adoption by focusing on the relevant enablers and their intensities. A hybrid Best Worst Method (BWM) – ELimination and Choice Expressing REality approach is used to test the applicability of developed offshore outsourcing focused enabler’s across four automotive business organisations in India and the adoption score of framework among case organisations is evaluated too. The intensity of offshore outsourcing focused enablers is analysed through BWM and the ranking of organisations and adoption index scores are computed through ELimination and Choice Expressing REality method. The developed framework possesses high adoption rate in offshore outsourcing initiatives across the case organisations. Findings of the study reveal that among the main enablers; managerial and strategic enabler holds the highest weight followed by technological enablers and organisational enablers. This study further presents the sensitivity analysis to check the robustness of developed framework by conducting experiments in different conditions. This research work will facilitate managers and professionals involved in practising offshore outscoring initiatives and results in higher cost advantages on labour and raw material, increased economies of scale, and higher sustainable business development.  相似文献   
25.
Oxidation studies were conducted on plasma sprayed coatings of Ni-20Cr-12.5Al containing one of the following: 1% MgO, 1% La2O3, 1% Y2O3, and 0.8% Y. The alloy powders containing dispersed oxides were prepared by a variety of processes employing attrition and ball milling. The TEM characterization of the plasma sprayed deposits of Ni-20Cr-12.5Al-1Y2O3 indicated that the oxide particles ranged from almost pure aluminum oxide to various compounds of aluminum and yttrium oxide. In cyclic tests conducted at 1150 and 1225°C, the coating containing 1% Y2O3 appeared to provide the best oxidation resistance. The oxidation resistance appeared to be influenced by the size and distribution of the oxide particles.  相似文献   
26.
27.
Nanocrystalline PLZT thin films of composition Pb1-xLaxZr0.52Ti0.48 (x = 0, 2, 5%) were deposited on silicon substrates by sol-gel process using lead acetate trihydrate, lanthanum nitrate hydrate, zirconium propoxide and titanium propoxide as lead, lanthanum, zirconium and titanium precursor materials. Experimental studies have been made on solitary waves in 2 mol% lanthanum doped sol-gel derived lead zirconate titanate thin films. The solitary waves are generated under the influence of external alternating electric field, which has the same frequency as the external field. These solitary waves propagate through the thin film upto its boundary and then reflect back. The magnitude of the solitary waves attenuates as they move away from the electrodes and their phase reverses on reflection. For certain frequencies of the external electric field, solitary waves exhibit resonance effect. Distortion in hysteresis loops has been demonstrated on the basis of solitary waves propagation in the film having different electrode area.  相似文献   
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29.
Stability of protective oxide films on Ti-base alloys   总被引:2,自引:0,他引:2  
Thermodynamic calculations are performed to estimate isothermal sections of Ti-Al-O, Ti-Si-O, and Ni-Al-O phase diagrams. Very small aluminum levels (<10–10 at. %) are needed to stabilize alumina on Ni-Al alloys. However, much higher aluminum (50%) and silicon (40%) levels are needed to stabilize alumina and silica on Ti-Al and Ti-Si alloys, respectively. These calculations suggest that the mechanism of formation of the protective oxide films on titanium-based alloys is radically different from that on nickel-based alloys. The aluminum levels needed to form a continuous film of alumina on nickel-based alloys are dominated by kinetic factors. On the other hand, thermodynamic factors appear to dominate the alloy compositions needed to form protective films of alumina and silica on titanium-based alloys. Further work is needed to evaluate any possible role of kinetic factors.  相似文献   
30.
Thermodynamic calculations and experiments were performed to determine the SO3 partial pressures and temperatures at which K2SO4-CoSO4 binary mixed liquid phases form on CoO and Co3O4 in the presence of K2SO4. The calculations and experiments are in excellent agreement. Similar calculations were also made of the compositions at the liquidus surface and the associated SO3 partial pressures for the K2SO4-Na2SO4-CoSO4 ternary system. These calculations show that the presence of K2SO4 substantially reduces the SO3 partial pressures required to stabilize a liquid salt phase on the surface of oxidized cobalt alloys at 600–800°C. Consequently, at these temperatures the hot corrosion in coal-fired systems, where K levels are high, is expected to be worse than in oil-fired systems, where K levels are low. This prediction was confirmed by experiments in a pressurized fluidized bed coal combustor and in an atmospheric pressure burner rig.  相似文献   
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