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151.
Mikami Y Abe K Abe T Aihara H Akemoto M Asano Y Aso T Aushev T Bahinipati S Bakich AM Ban Y Bay A Bizjak I Bondar A Bozek A Bracko M Browder TE Chao Y Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Danilov M Dong LY Dragic J Eidelman S Eiges V Fukunaga C Furukawa K Gabyshev N Garmash A Gershon T Gokhroo G Golob B Handa F Hara T Hayashii H Hazumi M Higuchi I Hinz L Hokuue T Hoshi Y Hou WS Huang HC Iijima T Ikeda H Inami K Ishikawa A Iwasaki H Iwasaki M Iwasaki Y Kang JH Kang JS Kapusta P 《Physical review letters》2004,92(1):012002
We report measurements of the properties of the D(+)(sJ)(2317) and D(+)(sJ)(2457) resonances produced in continuum e(+)e(-) annihilation near sqrt[s]=10.6 GeV. The analysis is based on an 86.9 fb(-1) data sample collected with the Belle detector at KEKB. We determine the masses to be M(D(+)(sJ)(2317))=2317.2+/-0.5(stat)+/-0.9(syst) MeV/c(2) and M(D(+)(sJ)(2457))=2456.5+/-1.3(stat)+/-1.3(syst) MeV/c(2). We observe the radiative decay mode D(+)(sJ)(2457)-->D(+)(s)gamma and the dipion decay mode D(+)(sJ)(2457)-->D(+)(s)pi(+)pi(-) and determine their branching fractions. No corresponding decays are observed for the D(sJ)(2317) state. These results are consistent with the spin-parity assignments of 0(+) for the D(sJ)(2317) and 1(+) for the D(sJ)(2457). 相似文献
152.
Tajima O Abe K Abe K Aihara H Akatsu M Aulchenko V Aushev T Bakich AM Bay A Bizjak I Bondar A Bozek A Bracko M Browder TE Chao Y Cheon BG Chistov R Choi Y Choi YK Chuvikov A Danilov M Dong LY Eidelman S Eiges V Fang F Gabyshev N Garmash A Gershon T Gokhroo G Haba J Hagner C Handa F Hasuko K Hazumi M Higuchi I Hokuue T Hoshi Y Hou WS Huang HC Iijima T Inami K Ishikawa A Itoh R Iwasaki Y Kang JH Kang JS Kapusta P Katayama N Kawai H Kichimi H Kim HJ Kim H Kim JH Kim SK Kinoshita K Koppenburg P 《Physical review letters》2004,92(10):101803
We report the observation of the decay D0-->phigamma with a statistical significance of 5.4sigma in 78.1 fb(-1) of data collected by the Belle experiment at the KEKB e+e- collider. This is the first observation of a flavor-changing radiative decay of a charmed meson. The Cabibbo- and color-suppressed decays D0-->phipi(0), phieta are also observed for the first time. We measure branching fractions B(D0-->phigamma)=[2.60(+0.70)(-0.61)(stat)+0.15-0.17(syst)] x 10(-5), B(D0-->phipi(0))=[8.01+/-0.26(stat)+/-0.47(syst)] x 10(-4), and B(D0-->phieta)=[1.48+/-0.47(stat)+/-0.09(syst)] x 10(-4). 相似文献
153.
Three diastereoisomers of 3-amino-4-hydroxy-2-(hydroxymethyl)pyrrolidine have been synthesised by a divergent route starting from trans-4-hydroxy-L-proline. Regio- and stereoselective introduction of the 3-amino and 4-hydroxyl functional groups was achieved using either a tethered aminohydroxylation reaction or by employing intra- and intermolecular epoxide-opening strategies. Preliminary biological data indicate that two of these novel amino pyrrolidines are moderate inhibitors of beta-galactosidase. 相似文献
154.
In a quite remarkable regio‐ and stereoselective manner, each of the (all‐E)‐polyene selenoates 5a – c is shown to undergo cascade radical‐mediated polycyclisations via consecutive 6‐endo‐trig reactions, leading to the corresponding all‐trans, anti, tri‐, penta‐ and heptacycles, i.e., 20 , 23 , and 25 , in good yields. The configurations of these `steroid‐like' polycycles followed from detailed examination and correlation of chemical shift data in their 13C‐NMR spectra. 相似文献
155.
Energy (E), enthalpy (ΔHa), entropy (ΔSa) and free-energy (ΔGa) of activation and the pre-exponential factor (k0) of the ordinary Arrhenius equation kDl = k0e–E/RT were estimated for diffusion-controlled crystal growth of SrWO4 from Na2WO4 melts. E increased slightly with increased cooling rates (RT). k0 was parallel to kDl and increased with increasing RT. ΔHa, ΔSa, and ΔGa did not change with the changes in RT and crystallization temperature (T0). The distance (d12), between a diffusing particle and its host necessary for a successful diffusion, was estimated. Such distances slightly increased with T0 and RT. 相似文献
156.
Adriano Costa de Camargo Anna Paula de Souza Silva Jackeline Cintra Soares Severino Matias de Alencar Cíntia Ladeira Handa Karina Silva Cordeiro Marcela Souza Figueira Geni R. Sampaio Elizabeth A. F. S. Torres Fereidoon Shahidi Andrs R. Schwember 《Molecules (Basel, Switzerland)》2021,26(2)
A clear gap with respect to the potential biological properties of wheat flavonoids exists in the available literature. This information is crucial for breeding programs aiming to produce new varieties presenting improved health benefits. Accordingly, advanced breeding lines of whole durum wheat were evaluated in this contribution. The highest recovery of phenolics was achieved using aqueous acetone (50:50, v/v), as verified by multi-response optimization, thus showing that phenolics could be largely underestimated by employing an inappropriate extraction. The concentration of derivatives of apigenin, the main phenolics present, ranged from 63.5 to 80.7%, as evaluated by LC–ESI-QTOF-MS. Phenolics from the breeding line 98 exhibited the highest ability in scavenging peroxyl radicals, reducing power as well as in terms of inhibition of pancreatic lipase activity, a key enzyme regulating the absorption of triacylglycerols. In contrast, none of the samples exhibited a significant anti-diabetic potential. Despite their high concentration compared to that of phenolic acids, results of this work do not support a significant antioxidant and pancreatic lipase inhibitory effect of durum wheat flavonoids. Therefore, breeding programs and animal and/or human trials related to the effect of durum wheat flavonoids on oxidative stress and absorption of triacylglycerols are discouraged at this point. 相似文献
157.
Development of a new amblyopia-training device with polarizing films used under binocular conditions
Optical Review - We developed an amblyopia-training device, which can be used easily and inexpensively under binocular conditions with polarizing films. The device uses two polarizing films: one is... 相似文献
158.
Kenji Handa 《Journal of Functional Analysis》2012,262(10):4488-4524
Continuous state branching processes with immigration are studied. We are particularly concerned with the associated (non-symmetric) Dirichlet form. After observing that gamma distributions are only reversible distributions for this class of models, we prove that every generalized gamma convolution is a stationary distribution of the process with suitably chosen branching mechanism and with continuous immigration. For such non-reversible processes, the strong sector condition is discussed in terms of a characteristic called the Thorin measure. In addition, some connections with notion from non-commutative probability theory will be pointed out through calculations involving the Stieltjes transform. 相似文献
159.
Mitul Patel Daniel Schwendemann Giorgia Spigno Shiyu Geng Linn Berglund Kristiina Oksman 《Molecules (Basel, Switzerland)》2021,26(15)
The development of bio-based nanocomposites is of high scientific and industrial interest, since they offer excellent advantages in creating functional materials. However, dispersion and distribution of the nanomaterials inside the polymer matrix is a key challenge to achieve high-performance functional nanocomposites. In this context, for better dispersion, biobased triethyl citrate (TEC) as a dispersing agent in a liquid-assisted extrusion process was used to prepare the nanocomposites of poly (lactic acid) (PLA) and chitin nanocrystals (ChNCs). The aim was to identify the effect of the TEC content on the dispersion of ChNCs in the PLA matrix and the manufacturing of a functional nanocomposite. The nanocomposite film’s optical properties; microstructure; migration of the additive and nanocomposites’ thermal, mechanical and rheological properties, all influenced by the ChNC dispersion, were studied. The microscopy study confirmed that the dispersion of the ChNCs was improved with the increasing TEC content, and the best dispersion was found in the nanocomposite prepared with 15 wt% TEC. Additionally, the nanocomposite with the highest TEC content (15 wt%) resembled the mechanical properties of commonly used polymers like polyethylene and polypropylene. The addition of ChNCs in PLA-TEC15 enhanced the melt viscosity, as well as melt strength, of the polymer and demonstrated antibacterial activity. 相似文献
160.
Via Sonogashira cross-coupling with different alkynes, 1,6 and 1,7 perylene diimides (PDIs) and perylene tetracarboxylic dianhydrides (PTCDs) were synthesized from the corresponding regioisomeric mixture of 1,6/1,7-dibromo precursors. Both bulky triphenyl propyne (TPP) groups and nonbulky hexyl groups allow for facile chromatographic separation. The optical properties of these compounds are discussed. Neutral bay substituents hypsochromically shift both the absorption and emission through deformation from planarity of the perylene core. 相似文献