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41.
Tsai-Yu Lin Chien-Wei Wu James C. Chen Y.H. Chiou 《Applied Mathematical Modelling》2011,35(9):4473-4489
Process capability indices provide numerical measures on process reproduction capability, which are effective tools for quality assurance. They are used to realize current situations of the process, and further improve the process problems to assure of product quality to meet the preset capability requirement. For analyzing process capability, most existing methods for assessing process performance were derived based on the traditional frequentist point of view. However, the sampling distributions of the estimated capability indices are usually so complicated, this makes establishing the exact confidence interval very difficult. In this study, we adopt a Bayesian approach to obtain an interval estimation, particularly for the index . Besides, a testing procedure is developed based on the derived results for practitioners to determine whether their manufacturing processes are capable of reproducing products satisfying the preset capability requirement when the manufacturing tolerance is asymmetric or symmetric. 相似文献
42.
Taian Li Mong-Feng Chiou Yajun Li Changqing Ye Min Su Mengyu Xue Xiaobin Yuan Chuanchuan Wang Wen-Ming Wan Daliang Li Hongli Bao 《Chemical science》2022,13(19):5667
Pyrroles are among the most important heterocycles in pharmaceuticals and agrochemicals. Construction of pyrrole scaffolds with different substituents and a free NH group, however, is challenging. Herein, a metal-free method for the synthesis of unsymmetrically tetrasubstituted NH-pyrroles using a consecutive chemoselective double cyanation is reported. The desired pyrroles were obtained with yields up to 99% and good functional group tolerance. Mechanistic studies identified a reaction mechanism that features a subtle sequence of first cyano-addition and migration, followed by cyano-addition and aromatization to afford the pyrrole skeleton. Pyrrolo[1,2-a]pyrimidines are synthesized as the synthetic applications of NH-pyrroles, and these pyrrolo[1,2-a]pyrimidines exhibit unpredicted time-dependent aggregation-induced emission enhancement (AIEE) properties.A novel method for the challenging synthesis of unsymmetrically tetrasubstituted NH-pyrroles from chalcone derivatives is reported. The pyrrolo[1,2-a]pyrimidine derivatives that were synthesized from NH-pyrroles exhibit AIE and AIEE property. 相似文献
43.
An Analytic solution is presented of the problem of turbulent heat transfer in pipes with internal heat generation and insulated wall by applying a recently-developed eddy conductivity model. The results agree closely with available experimental data for a wide range of Prandtl number (0.02–10.5). 相似文献
44.
Triulzi RC Micic M Giordani S Serry M Chiou WA Leblanc RM 《Chemical communications (Cambridge, England)》2006,(48):5068-5070
An immunoassay based upon photoluminescent gold quantum dots aimed at detecting human IgG in aqueous solution from micromolar to nanomolar concentrations is described. 相似文献
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Asokan K Tsai HM Bao CW Chiou JW Pong WF Sonia G Anand TJ 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,70(2):454-457
X-ray absorption spectroscopic measurements have been used to compare the electronic structures of swift heavy ions (100 MeV Si ions) irradiated and pristine Ni-Al nanocrystalline films. Results from X-ray diffraction (XRD), X-ray absorption near-edge structure (XANES) spectra at Al K-, and Ni L(2,3)-edges and extended X-ray absorption fine structure (EXAFS) at Ni K-edges are discussed. The observed XRD peaks indicate the improvement of crystalline nature and Al(111) clustering after the swift heavy ion interactions. While the XANES spectra at Ni L(2,3)-edges show decrease in the intensity of white line strength, the Al K-edge shows increase in intensity after irradiation. Above results imply that swift heavy ions induce low Z (i.e., Al) ion mass transport, changes in Al sp-Ni-d hybridization, and charge transfer. EXAFS results show that crystalline nature is improved after swift heavy irradiation which is consistent with XRD results. 相似文献
47.
Enantiomeric syntheses of (-)-homopipecolic acid and (-)-pelletierine have been achieved by chiral resolution of tropanol followed by Baeyer-Villiger oxidation. The methodology provides a practical route for the synthesis of optically pure piperidines. 相似文献
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Transient absorption difference spectroscopy was used to study the temperature dependence of the P798+ decay kinetics in heliobacteria. For membrane samples, two components were obtained from the fitting of kinetic traces in the temperature range of 4-29 degrees C. A 3-9 ms component representing the cytochrome (cyt) c oxidation has an activation energy of 33.0 +/- 2.8 kJ/mol. A 12-22 ms component representing either P798+FX- or P798+FA/B- recombination has an activation energy of 15.3 +/- 2.4 kJ/mol. In isolated reaction centers (RC), only one 14 ms component due to P798+FX- recombination was obtained in this temperature range. The Arrhenius plot shows that the recombination rate of this P798+FX- state is temperature independent in the near room temperature range. For RC in the temperature range of 60-298 K, a 12-15 ms decay was obtained at temperatures greater than 240 K. Biphasic decay traces (12-15 ms and 2-4 ms components) were obtained at temperatures between 170 K and 230 K. Only one 2-4 ms component was found at temperatures lower than 160 K. The gradual switchover from the 12-15 ms to the 2-4 ms component upon cooling may indicate the shift of the P798+FX- recombination state to a state that is prior to P798+FX-, although other interpretations can not be excluded. The absorption difference spectrum (delta A @ 160 K - delta A @ 240 K) in the blue region shows a positive amplitude below 405 nm and a negative amplitude above 405 nm implying that the 2-4 ms decay component may be due to the recombination of P798+A1-, where A1 is a quinone-type acceptor. 相似文献