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Hydroxylamine was found to be a mild reagent for conversion of arylboronic acids and their pinacolyl boronate esters into phenols. This procedure works on most arylboronic acids at room temperature, yielding phenols in moderate to good yields, and efficiently on arylboronates also yielding phenols in good yields.  相似文献   
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Molecular Diversity - Soluble epoxide hydrolase (sEH) enzyme plays an important role in the metabolism of endogenous chemical mediators, epoxyeicosatrienoic acids, which are involved in the...  相似文献   
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Two new three-step classes of optimal iterative methods to approximate simple roots of nonlinear equations, satisfying the Kung-Traub’s conjecture, are designed. The development of the methods and their convergence analysis are provided joint with a generalization of both processes. In order to check the goodness of the theoretical results, some concrete methods are extracted and numerical and dynamically compared with some known methods.  相似文献   
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In polyelectrolyte-enhanced ultrafiltration (PEUF), a water-soluble anionic polyelectrolyte (in this study sodium polystyrene sulfonate or PSS) is added to hard water. The calcium and magnesium bind to the polymer which has a high enough molecular weight to be rejected by an ultrafiltration membrane. The permeate is softened water. Economically, the PSS needs to be recovered from the retentate for reuse. Three methods of recovery developed in this study were addition of NaCl, Na2CO3 or HCl to PEUF to regenerate PSS. Of the three PEUF processes considered, NaCl/PEUF as compared to Na2CO3/PEUF and HCl/PEUF provided the best scheme for the water softening process. PEUF is shown in this study to be competitive with lime softening at low flow rates. The PEUF process is more expensive than ion exchange for a stream containing only hardness ions. However, PEUF becomes nearly comparable with ion exchange for a stream containing hardness ions as well as bacteria, viruses and pyrogen. The cost comparisons are based on fully continuous operations and include treatment of waste streams from each process.  相似文献   
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This paper examines the robustness of the Welch test , the James test as well as Tan's Anova test (to be referred as Fβ test) for testing parallelism in k straight lines under heteroscedasticity and nonnormality. Results of Monte Carlo studies demonstrate the robustness of all tests with respect to departure from normality. Further, there is hardly any difference between these methods with respect to both power and size of the test.  相似文献   
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