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1.
J Org Chem ; 82(14): 7503-7511, 2017 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-28641007

RESUMEN

A palladium-catalyzed reaction for preparing various endocyclic allenes was developed. The substrates for the reaction were readily available ω-(pronucleophile-tethered)-3-bromo-1,3-alkadienes, and a palladium-catalyst facilitated their unimolecular SN2'-cyclization in the presence of potassium tert-butoxide to give the corresponding 9- to 16-membered endocyclic allenes in fair yields of up to 67% together with the dimeric 16- to 32-membered endocyclic bis-allenes and other oligomeric/polymeric intermolecular reaction products. For higher yields of the monomeric endocyclic allenes, the reaction needed to be conducted under high-dilution conditions. Using a chiral palladium catalyst, axially chiral endocyclic allenes were obtained in up to 70% ee.

2.
J Appl Stat ; 50(4): 827-847, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36925911

RESUMEN

Phase-I analysis of historical data from a statistical process is a strategic problem in Statistical Process Monitoring and control. Before the establishment of process stability, it is challenging to model historical data. Consequently, a distribution-free approach is a natural choice in Phase-I monitoring. Existing distribution-free Phase-I control charts are suitable for detecting instability in location and scale parameters only and are often insensitive in complex processes involving skewness or shape parameters. A new Phase-I control chart is proposed to identify more general shifts, including location, scale and skewness. The proposed Phase-I scheme is efficient in such a situation. The proposed Phase-I scheme uses subsamples, and the plotting statistic is based on the omnibus multi-sample linear rank statistic corresponding to the location, scale and skewness shifts. The new scheme can identify subsamples that are not in control, and it can also indicate one or more process parameters where a deviation has occurred. The encouraging performance of the proposed scheme is established with a large-scale numerical study based on Monte-Carlo in detecting shifts of various nature in a comprehensive class of situations. An illustration based on monitoring the waiting time data from a customer service centre is given. Some concluding remarks and some future research problems are also offered.

3.
Rev Sci Instrum ; 93(8): 084905, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-36050116

RESUMEN

A new temperature measurement method-the dual two-color method-was developed to accurately measure the temperature over an ultra-wide temperature range (200-3600 °C) for ITER divertor infrared thermography. This novel method introduces a third wavelength filter to the conventional two-color method by replacing the shorter single wavelength bandpass filter with a customized dual-bandpass filter having two transmission bands, without having to add a third infrared camera. The dominant wavelength band of the total radiance through the dual-band filter changes automatically as the temperature increases and, consequently, either the shorter or longer wavelength band of the dual-bandpass filter is used to establish the two-color combination at both low and high temperatures. The dual two-color method increased the acceptable measurement error of the two-color radiance ratio for the temperature measurement requirement of the ITER divertor infrared thermography to 9.45% from that of 4.3% when using the conventional two-color method.

4.
IJU Case Rep ; 5(5): 406-409, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36090927

RESUMEN

Introduction: Most seminal vesicle malignancies are secondary to prostate or bladder cancer. Herein, we report a case of primary clear cell carcinoma of the seminal vesicle. Case presentation: A 27-year-old man was referred to our department for hematospermia and macroscopic hematuria. A digital rectal examination showed a soft elastic prostatic mass. Cystoscopy showed no bladder abnormalities, and tumor marker tests were unremarkable. Contrast-enhanced computed tomography and magnetic resonance imaging revealed a cystic tumor containing an enhanced nodule near the prostate and seminal vesicle. The tumor was removed en bloc with the prostate and seminal vesicle through a laparoscopic radical prostatectomy. A histopathologic examination confirmed the diagnosis, with the tumor likely arising from a remnant Müllerian epithelium. A 1-year follow-up revealed local tumor recurrence, prompting laparoscopy. Conclusion: A standard therapy for primary seminal vesicle carcinoma has not been established. Further studies are necessary to determine the optimal treatment strategy.

5.
Rev Sci Instrum ; 91(6): 063508, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32611050

RESUMEN

This study developed a new heat flux reconstruction code based on the dual reciprocity boundary element method for the International Thermonuclear Experimental Reactor (ITER) divertor infrared (IR) thermography system. To use divertor heat flux reconstruction in ITER, we modeled the boundary condition between the coolant pipe inner wall and the coolant based on the temperature-dependent heat transfer coefficient and also considered the temperature dependence of tungsten thermal properties. Using this reconstruction code, we evaluated the sensitivity of the input data errors, divertor coolant temperature, and surface temperature errors on the accuracy of heat flux reconstruction by using simplified heat flux profiles, which are spatially uniform on the top surface of the monoblocks. This heat flux reconstruction method demonstrated that highly accurate heat flux reconstruction can be achieved for high heat flux cases in ITER; however, further studies are needed for low heat flux reconstruction.

6.
Org Lett ; 11(18): 4240-3, 2009 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-19697944

RESUMEN

Treatment of acetal-tethered (allenylmethyl)silanes, which were obtained from the corresponding 3-bromo-5-silyl-1,3-pentadienes by a Pd-catalyzed reaction with an acetal-tethered malonate, with TiCl(4) gave not only vinylcyclohexene derivatives via a standard S(E)2' pathway but also unusual allenylcyclopentane species via cyclization at the delta-position. Deuterium-labeling experiments revealed participation of a 1,2-hydride shift in a carbocation intermediate for the formation of the latter products.

7.
Chem Commun (Camb) ; (47): 7366-8, 2009 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-20024230

RESUMEN

Palladium-catalyzed monofluoromethylation of substituted 2-bromo-1,3-dienes using fluorobis(phenylsulfonyl)methane (FBSM) as a pronucleophile gave previously unknown monofluoromethylated allenes in high yields, which are the isosteres of biologically attractive allenic alcohols.


Asunto(s)
Alcadienos/síntesis química , Flúor/química , Hidrocarburos Fluorados/química , Metano/análogos & derivados , Paladio/química , Compuestos de Bromina/química , Catálisis , Metano/química , Metilación , Estructura Molecular
8.
Biophys J ; 89(3): L22-4, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16040763

RESUMEN

Frequency-dependent absorption coefficients and refractive indices of amino acids (glycine and l-alanine) and polypeptides (polyglycine and poly-l-alanine) in the wavenumber region from 7 to 55 cm(-1) were measured by terahertz time-domain spectroscopy. A vibrational band was observed at 45.5 cm(-1) for polyglycine, which was assigned as an interchain mode. The reduced absorption cross sections of the amino acids and polypeptides show power-law behavior. The exponents are different between the monomers and polymers, and those of the two polypeptides suggest that the time dependences of the total dipole moments are similar in the timescale of subpico- to picoseconds.


Asunto(s)
Aminoácidos/química , Péptidos/química , Espectrofotometría/métodos , Alanina/química , Biofisica/métodos , Glicina/química , Modelos Estadísticos , Polímeros/química , Espectrofotometría Infrarroja , Temperatura , Factores de Tiempo
9.
Appl Opt ; 41(36): 7556-60, 2002 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-12510919

RESUMEN

We demonstrate that a coaxially pumped, large-aperture ultraviolet power-amplifier module with solid-state tunable laser medium Ce(3+):LiCaAlF6 has 98-mJ, 290-nm, and 3-ns output pulses with a sufficient extraction efficiency of 25%. The detailed information of design parameters, including the gain-coefficient dependence on pump condition, is successfully accumulated for further energy scaling for a terawatt-class ultraviolet chirped pulse amplification laser system or a high-pulse-energy laser system.

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