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11.
Girendra N. Kulsrestha Uma Shankar Jaipal S. Sharma Jasvinder Singh 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1991,50(1):57-65
Liquid-phase oxidation of cyclohexane with Co(III) catalyst and gaseous oxygen was found to be influenced by reaction temperature, catalyst concentration and the duration. Maximum adipic acid product selectivity (77%) with about 85% cyclohexane conversion was attained at 100°C using catalyst: cyclohexane molar ratio 0·08. Under these conditions more than 80% cyclohexane was converted in the first hour, although selectivity to adipic acid continued to increase for the next 5 h. Cyclohexyl acetate and cyclohexyl monoadipate were identified as important intermediates. This study supports the mechanism proposed by Schultz, J. G. D. and Opchenko, A., J. Org. Chem., 38 (21) (1973) 3729. 相似文献
12.
The static charge sensitive bed (SCSB) consists of a sensitive movement detector embedded in a mattress. When a subject rests on the bed, a single electrical signal, containing components reflective of cardiac, respiratory, and body movement related motion, is produced. This paper describes a digital signal processing technique to separate the BCG from the SCSB signal. An evaluation of this algorithm was conducted using recordings from normal volunteers. Comparisons with simultaneously recorded reference signals indicated that the algorithm performed satisfactorily in a laboratory environment. 相似文献
13.
Prediction of the effects on dynamic response due to distributed structural modification with additional degrees of freedom 总被引:1,自引:0,他引:1
Huajiang Hang Krishna Shankar Joseph C.S. Lai 《Mechanical Systems and Signal Processing》2008,22(8):1809-1825
The aim of this study is to investigate means of efficiently assessing the effects of distributed structural modification on the dynamic properties of a complex structure. The dynamic properties of the modified structure can be determined by experimental testing or numerical simulation, both of which are complex, expensive and time-consuming. Assuming that the original dynamic characteristics are already established and that the modification is a relatively simple attachment, the modified dynamic properties may be determined numerically without solving the equations of motion of the full-modified structure. The frequency response functions (FRFs) of the modified structure can be computed by coupling the original FRFs and a delta dynamic stiffness matrix for the modification introduced. The validity of this approach is investigated by applying it to a cantilever beam to which a smaller beam is attached as modification. The original FRFs were obtained experimentally as well as numerically. The delta dynamic stiffness matrix was determined numerically by modeling the attachment and part of the original structure including the attachment points. The FRFs of the modified beam were then computed. Good agreement is obtained by comparing the results to the FRFs of the modified beam determined experimentally as well as by numerical modeling of the complete modified structure. 相似文献
14.
Glory H. Anila Vigneswaran C. Jagtap Sujeet S. Shruthi R. Hariharan G. Sriram V. S. Shankar 《Neural computing & applications》2021,33(11):6065-6093
Neural Computing and Applications - “Brain–Computer Interface” (BCI)—a real-life support system provides a way for epileptic patients to improve their quality of life. In... 相似文献
15.
Estimation of distribution algorithms (EDAs) are stochastic optimization techniques that explore the space of potential solutions by building and sampling explicit probabilistic models of promising candidate solutions. While the primary goal of applying EDAs is to discover the global optimum or at least its accurate approximation, besides this, any EDA provides us with a sequence of probabilistic models, which in most cases hold a great deal of information about the problem. Although using problem-specific knowledge has been shown to significantly improve performance of EDAs and other evolutionary algorithms, this readily available source of problem-specific information has been practically ignored by the EDA community. This paper takes the first step toward the use of probabilistic models obtained by EDAs to speed up the solution of similar problems in the future. More specifically, we propose two approaches to biasing model building in the hierarchical Bayesian optimization algorithm (hBOA) based on knowledge automatically learned from previous hBOA runs on similar problems. We show that the proposed methods lead to substantial speedups and argue that the methods should work well in other applications that require solving a large number of problems with similar structure. 相似文献
16.
IR and Raman spectra of glass ceramics based on PbO-Cr2O3-B2O3glass composition system have been studied. The bands characteristic of BO3. and BO4 functional groups are present in all the samples. An incorporation of Al2O3(up to 5 mol%) in the initial glass composition considerably changes the glass network structure and relative concentrations of BO3 and BO4 groups. The composition 50 PbO-20 Cr2O3-25 B2O3-5 Al2O3(in mol%) reveals a maximum fraction of boron in the BO4 group. A sample of this composition heat treated at 850° C for 25 h shows a maximum crystallization fraction with Pb2O · CrO4 as a prominent crystalline phase. The glasses irradiated with rays inhibit the crystallization into the Pb2O · CrO4 phase. They also show relatively smaller thermal conductivity. 相似文献
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19.
Diels-alder adducts from safflower oil fatty acids: I. Maleic anhydride as dienophile 总被引:1,自引:0,他引:1
G. S. R. Sastry B. G. K. Murthy J. S. Aggarwal 《Journal of the American Oil Chemists' Society》1971,48(11):686-688
The Diels-Alder reaction between alkali conjugated and elaidinized safflower oil fatty acids and maleic anhydride was studied
under various experimental conditions. The principal product which was obtained in 51–55% yields was a mixture of the adduct
of maleic anhydride and maleic acid in 40∶60 proportions. The isolation and properties of this mixed adducts from the reaction
mixture and their conversion to trimethyl, tributyl and triallyl esters are described. The trimethyl ester was also obtained
in good yield from the methyl esters of the fatty acids and dimethyl maleate. 相似文献
20.
Preparation and surface- active properties of polyoxyethylene-glycol (600) monoesters of fatty acids
T. Chandrasekhara Rao Y. Sita Rama Sastry R. Subbarao Gollamudi Lakshminarayana 《Journal of the American Oil Chemists' Society》1977,54(1):15-16
Polyoxyethyleneglycol (PEG-600) monoesters of undecylenic, lauric, myristic, palmitic, stearic, oleic, ricinoleic and 12-hydroxystearic
acids were prepared in 80-85% yield by reacting PEG with boric acid, esterifying the resultant borate with fatty acid, and
selectively hydrolyzing the borate ester; their surface active properties were evaluated. Increase in acyl chain length increased
the surface tension. The presence of a double bond or hydroxyl group in C18 series improved the wetting and emulsifying proper-ties. Unsaturation in the fatty acid chain reduced the foaming power. 相似文献