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81.
Haiderali M. Bhavnagary Tirunillai S. Krishnamurthy Suvendu K. Majumder 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1979,29(7):433-436
Optimum conditions have been presented for the production of methyl bromide by employing the reactants, sulphur, methyl alcohol, liquid bromine and water. For the maximum recovery of methyl bromide from liquid bromine used in the reaction, a 5% excess of sulphur and 30% excess of water than the stoichiometric quantities were found necessary. The addition of liquid bromine to the reaction mixture at slower rates of 0.5 to 2.5 cm3 min?1, reduced the loss of bromine as sulphur bromide and increased the yield of methyl bromide from 42 to 94.3%. With these standardised conditions, the product had a methyl bromide content of 98.2% with an overall yield of 94.42% based on liquid bromine. 相似文献
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The paper describes the implementation of a centralised control-design scheme in a real-time laboratory-based dynamic simulator. A centralised multivariable-control algorithm is designed employing remote feedback signals considering delay in signal transmission. The transmitted signals can be used for multiple-swing-mode damping using a single controller. Such an algorithm is numerically intensive owing to the high controller size and the predictor that takes care of the delay in signal transmission. The performance of the proposed controller is demonstrated by practical implementation using a rapid-prototyping controller mounted on a PC-ATX. Results of the experimental tests are shown for a detailed model of the power system implemented using Linux PC-based multiprocessor technology. 相似文献
84.
AbstractSteganography is a data-concealing technique that provides a covert communication. This paper proposes a spatial domain color steganography method that uses a neighboring pixel-pair differencing concept to enhance the embedding capacity. The proposed method considers the distortion tolerance capacity of each color plane and the difference value between two neighboring pixels while deciding the number of bits that can be concealed in that pixel-pair. Each plane is divided into some disjoint blocks of size 3?×?3 pixels. The method forms eight pairs of pixels in one block using the eight-neighboring pixel concept, which enables the method to utilize all the edge pixels in all probable directions. It also uses the XOR encoding technique before the embedding process. This step provides an additional layer of security to the secret information. The simulation results show that the proposed method is able to achieve a high embedding capacity with good visual quality as per the calculation of imperceptibility metrics. The robustness of the method is tested by RS steganalysis and pixel difference histogram analysis. Further, a comparison between the proposed method and the existing methods on the basis of embedding capacity and stego image quality is shown. 相似文献
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JM Bhatavdekar DD Patel N Ghosh PR Chikhlikar TI Trivedi TP Suthar SS Doctor NG Shah DB Balar 《Canadian Metallurgical Quarterly》1997,40(7):785-790
Lanepitant is a high-affinity, selective neurokinin-1 receptor (NK-1) and is effective in the dural inflammation model of acute migraine. Lanepitant 30, 80, and 240 mg given orally was evaluated in a double-blind, placebo-controlled crossover study to determine its effect in reducing migraine pain and severity of associated symptoms. Outpatients treated four migraine headaches of moderate or severe pain intensity with study drug according to a randomization schedule. They recorded their pain intensity and severity of migraine-associated symptoms at 30, 60, 90, and 120 min. Although 53 patients were randomly allocated to a treatment sequence, only 40 patients completed all treatments. There was no statistically significant difference in improvement in migraine pain at any time for any of the treatments. Additionally, there was no change in severity of migraine-associated symptoms associated with lanepitant therapy. No adverse events could be attributed to lanepitant. Lanepitant was ineffective orally in treating acute migraine in this trial. This may be due to poor bioavailability during a migraine attack. Alternatively, the neurogenic inflammation hypothesis may not apply to migraine. 相似文献
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