A study of adsorption characteristics of the paraquet using stationary electrode

601-604Paraquet has been reduced at cathode and cyclic voltammograms have been recorded. The adsorption studies on electrode surface reveals that new species has been formed which is characterised by cyclic voltammetry and Raman spectroscopy. The plot ip vs √v givesa linear curve which further supports our conclusion

Supercritical carbon dioxide Brayton cycle for concentrated solar power

Supercritical carbon dioxide based Brayton cycle for possible concentrated solar power applications is investigated and compared with trans- and sub-critical operations of the same fluid. Thermal efficiency, specific work output and magnitude of irreversibility generation are used as some of the performance indicators. While the thermal efficiency increases almost linearly with low side pressure in the sub- and trans-critical cycles, it attains a maximum in the supercritical regime at 85 bar after which there are diminishing returns on increasing the low side pressure. It is also found that supercritical cycle is capable of producing power with a thermal efficiency of >30% even at a lower source temperature (820K) and accounting for foreseeable non-idealities albeit with a higher turbine inlet pressure (similar to 300 bar) which is not matched by a conventional sub-critical cycle even with a high source temperature of 978K. The reasons for lower efficiency than in an ideal cycle are extracted from an irreversibility analysis of components, namely, compressor, regenerator, turbine and gas cooler. Low sensitivity to the source temperature and extremely small volumetric flow rates in the supercritical cycle could offset the drawback of high pressures through a compact system

A trade-off between maxima in efficiency and specific work output of super- and trans-critical CO2 Brayton cycles

Several operational aspects for thermal power plants in general are non-intuitive and involve simultaneous optimization of a number of operational parameters. In the case of solar operated power plants, it is even more difficult due to varying heat source temperatures induced by variability in insolation levels. This paper introduces a quantitative methodology for load regulation of a CO2 based Brayton cycle power plant using the `thermal efficiency and specific work output' coordinate system. The analysis shows that a transcritical CO2 cycle offers more flexibility under part load performance than the supercritical cycle in case of non-solar power plants. However, for concentrated solar power, where efficiency is important, supercritical CO2 cycle fares better than transcritical CO2 cycle. A number of empirical equations relating heat source temperature, high side pressure with efficiency and specific work output are proposed which could assist in generating control algorithms. (C) 2015 Elsevier B.V. All rights reserved

Biokinetics of ⁶⁵Zn in liver and whole body and its bio-distribution in nickel treated protein deficient rats

969-975This study was designed to determine the effect of nickel treatment on biological half-lives of 65Zn in whole body and liver as well as on distribution of 65Zn in different organs of protein deficient rats. Nickel sulfate at a dose level of 800mg/l in drinking water was administrated to normal control as well as to protein deficient rats for 8 weeks. A significant increase was found in fast and slow components of biological half lives of 65Zn in whole body and only fast component in liver of protein deficient rats. Interestingly, slow component in whole body and fast component in liver of nickel treated protein deficient rats were not different from normal controls though they were significantly elevated in protein deficient rats. On the other hand, slow component of 65Zn was also not altered in nickel treated protein deficient rats, which however, was significantly decreased in nickel treated rats. Protein deficiency led to a marked elevation in per cent uptake of 65Zn in brain and caused significant depression in liver, kidney and intestine. However, uptake of 65Zn in brain showed a significant depression in nickel treated rats, whereas the uptake was elevated in brain in nickel treated protein deficient rats. In conclusion, protein deficient conditions seem to be playing a dominant role in context with the distribution of 65Zn in different organs when nickel is administered to protein deficient rats. However nickel alone is seen to cause adverse effect on the distribution of 65Zn

SIMULATION MODELING OF OUTBOUND LOGISTICS OF SUPPLY CHAIN: A CASE STUDY OF TELECOM COMPANY

The present work has been done for a telecom company with a focus on cost and flexibility in effectively deals with changing scenario. In this paper, the major problems faced by company at upper end of supply chain and sales outlet are analyzed and a complete inventory analysis on one of a company product is done by developing an Inventory model for the company bound store/distribution center and optimal inventory policy is suggested for the outbound logistics on the basis of simulation analysis. This model is flexible enough to respond to the market fluctuations more efficiently and effectively. The model is developed in Microsoft EXCEL.  Significance: Increasing competitive pressures and market globalization are forcing the firms to develop supply chains that can quickly respond to customer needs. The inventory model for the company’s bound store/outbound logistics has been developed & simulated to reduce the operating cost, stock out, to make supply chain agile.Key words: Supply Chain, Outbound Logistics, Information Technology, Simulation, Operating Cost, Inventory.

Hydrogenation and Dehydrogenation of N-Heterocycles Under Cp*Co(III)-Catalysis

International audienceTo realize the goal of a carbon-free energy economy, it is crucial to discover reactions that utilizes sustainable resources as an alternatives to fossil feedstocks. In this study, a well-defined, air-stable Cp*Co(III)-catalyst for transfer hydrogenation of quinolines derivatives and oxidative dehydrogenation of cyclic amines in water is developed. While the former reaction is promoted by formic acid as transfer hydrogenating reagent, the latter is mediated by molecular oxygen as the sole oxidant. These processes provide new avenues for the investigation of air-stable cobalt catalysts for environmentally benign hydrogenation and dehydrogenation reactions

Comparison of incidence of dentinal defects after root canal preparation with continuous rotation and reciprocating instrumentation

AbstractBiomechanical preparation is one of the most important steps in endodontic therapy. Rotary instrumentation has facilitated this step. Nowadays the market is flooded with different types of rotary instruments. The present study compared the root dentinal crack formation with continuous rotating versus reciprocating root canal preparation methods. One hundred and fifty freshly extracted teeth were used for the study. They were divided into 5 groups with 30 teeth in each group. Thirty teeth were kept under control group A and no root canal preparation was done for this group. Another 30 teeth were prepared with hand files which were kept under control group B. In the experimental groups (sample size, n=30 each) root canals were prepared with ProTaper, K3XF rotary system and WaveOne. Sectioning of these teeth was done at 3, 6 and 9mm from the apex and were evaluated for the presence of any defects. Root dentinal cracks were produced with each type of rotary instruments. Statistical analysis showed no significant difference in root dentinal crack formation between control groups and WaveOne system. There was statistically significant difference in root dentinal crack formation when the canals were prepared with ProTaper and K3XF rotary system. So it was concluded, that continuous rotating instruments could produce dentinal crack formation. Root canal instruments with reciprocating movement appear to be a better option than continuous rotation movement

Thermo-economic evaluation of ORCs for various working fluids

An inclusive component-level technical and economic assessment procedure for the general design and operating strategy of Organic Rankine Cycles (ORC) for use across major application categories (waste heat recovery, solar thermal, geothermal) and sub-MW scales can be an important tool for leveraging the cost-effective deployment of low and medium temperature power cycles. Previous analyses and design approaches tended to focus on thermodynamic efficiency rather than financial performance. To bridge this gap, a general thermo-economic optimization of sub 500 kWe ORCs is developed using a 7-dimensional design space with minimum investment cost per unit of nameplate electricity production as an objective function. Parameters used include working fluid, heat source temperature, pinch in condenser, boiler (HEX) and regenerator, expander inlet pressure and air cooled condenser area. Optimized power block configurations are presented for the application of ORCs with waste or ``free'' heat sources and solar heat input for power scales of 5, 50 and 500 kWe to facilitate rapid selection of design parameters across a wide range of thermal regimes. While R152a yields the lowest cost ORCs in the case of the former, isopentane is found to be more cost effective in the latter case for heat source temperatures between 125 and 275 degrees C. (C) 2016 Published by Elsevier Ltd