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31.
The classical theory of radiation is extended to a relativistic linear oscillator, and the radiation properties are determined. Some basic particular cases are analyzed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 7–11, November, 1975.In conclusion the authors thank Prof. A. A. Sokolov for his interest in the work. 相似文献
32.
Parity-violating electron deuteron scattering and the proton's neutral weak axial vector form factor
Ito TM Averett T Barkhuff D Batigne G Beck DH Beise EJ Blake A Breuer H Carr R Clasie B Covrig S Danagoulian A Dodson G Dow K Dutta D Farkhondeh M Filippone BW Franklin W Furget C Gao H Gao J Gustafsson K Hannelius L Hasty R Hawthorne-Allen AM Herda MC Jones CE King P Korsch W Kowalski S Kox S Kramer K Lee P Liu J Martin JW McKeown RD Mueller B Pitt ML Plaster B Quéméner G Réal JS Ritter J Roche J Savu V Schiavilla R Seely J Spayde D Suleiman R Taylor S Tieulent R Tipton B Tsentalovich E 《Physical review letters》2004,92(10):102003
We report on a new measurement of the parity-violating asymmetry in quasielastic electron scattering from the deuteron at backward angles at Q2=0.038 (GeV/c)2. This quantity provides a determination of the neutral weak axial vector form factor of the nucleon, which can potentially receive large electroweak corrections. The measured asymmetry A=-3.51+/-0.57 (stat)+/-0.58 (syst) ppm is consistent with theoretical predictions. We also report on updated results of the previous experiment at Q2=0.091 (GeV/c)2, which are also consistent with theoretical predictions. 相似文献
33.
The regioselective alkoxycarbonylation of phenylacetylene into various cinnamate esters was achieved with a catalyst system formed from palladium (II), 1,4‐bis(diphenylphosphino) butane (dppb) and salicylborate complex in acetonitrile as a solvent. The influence of various parameters on the overall conversion of phenylacetylene and the selectivity of the reaction were studied systematically by varying the type of palladium complex, acids promoter, CO pressure, temperature and the reaction time. This investigation allowed us to obtain the predominant formation of cinnamate esters with excellent selectivity (90–96%). Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
34.
Heck reactions between iodobenzene and methyl acrylate were carried out in monoglyme and diglyme as solvents, using different ligands and palladium sources, and good to high yields were obtained in the production of (E)‐substituted olefins. The ionic liquid BmimCl was successfully utilized as pre‐ligand to substitute triphenylphosphine. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
35.
C. Lam Y. F. Zhang Y. H. Tang C. S. Lee I. Bello S. T. Lee 《Journal of Crystal Growth》2000,220(4):466-470
Si nanoparticles have been synthesized by ball-milling of graphite and SiO2 powders. The solid-phase reaction, C(graphite)+SiO2→Si+CO2, was found to be a novel technique for fabrication of ultrafine Si particles. The reduced Si in the powder assembled as nanoparticles with a wide range of diameters. Multiple-peak structures were observed in the photoluminescence spectra of the Si nanoparticles at room temperature. The peak energies were found to coincide with the PL peak pinning energies previously reported in porous Si. Thus, the fine structures of luminescence spectra could be attributed to the size quantization of the Si nanoparticles formed via solid-phase reaction during ball-milling. 相似文献
36.
37.
Effectiveness of Photodynamic Therapy in Elimination of HPV‐16 and HPV‐18 Associated with CIN I in Mexican Women
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Elizabeth Maldonado Alvarado Martha Olivia Osorio Peralta Alejandra Moreno Vázquez Lydia Alejandra Martínez Guzmán Maria Eugenia Melo Petrone Zulma Iveth Enriquez Mar Dora Estela Jovel Galdamez Bárbara Carrión Solana Guadalupe Balderas Martínez Eduarda Parra Rossana Inés Castellanos Oliveros Rosa Linda Bello Leiva Araceli Espinosa Montesinos Citlalli Barrera Mendoza Selma Eugenia Medina García Eva Ramón Gallegos 《Photochemistry and photobiology》2017,93(5):1269-1275
This study aimed to determine the effectiveness of photodynamic therapy (PDT), using δ‐aminolevulinic acid (5‐ALA), in the elimination of premalignant cervical lesions in Mexican patients with human papillomavirus (HPV) infection and/or cervical intraepithelial neoplasia (CIN). Thirty women diagnosed with CIN I and/or positive for HPV participated in the study. Topical 6% 5‐ALA in gel form was applied to the uterine cervix; after 4 h, the lesion area was irradiated with a light dose of 200 J cm?2 at 635 nm. This procedure was performed three times at 48‐h intervals. Clinical follow‐up was performed at 3, 6, and 12 months after the initial PDT administration, by colposcopy, cervical cytology, histopathological analysis, polymerase chain reaction, and hybrid capture. Of HPV‐infected patients without evidence of CIN I, 80% cleared the infection, while HPV associated with CIN I was eliminated in 83% of patients (P < 0.05). At 12 months, CIN I had regressed in 57% of patients, although this response was not statistically significant. PDT using 6% 5‐ALA is concluded to be effective in eliminating HPV infection associated or not with CIN I. 相似文献
38.
Mansur B. Ibrahim Rami Suleiman Mohammed Fettouhi Bassam El Ali 《Transition Metal Chemistry》2017,42(1):1-8
A palladium(II)-bis(oxazoline) complex supported on silica (Pd-BOX-Si) was prepared, characterized and applied as a catalyst in Mizoroki–Heck cross-coupling reactions. The bis(oxazoline) (BOX) ligand has a hydroxyl group that can be anchored to 4-benzyl chloride-functionalized silica gel, followed by the coordination of palladium(II) chloride. The catalytic activity and the recyclability of Pd-BOX-Si have been investigated in the production of cinnamic acid derivatives via Mizoroki–Heck coupling reactions of acrylates with aryl halides; The Pd-BOX-Si catalyst demonstrated excellent catalytic activity. Characterization of the recycled Pd-BOX-Si catalyst revealed its good stability under the reaction conditions employed. 相似文献
39.
Aránzazu Martínez-Gómez Ernesto Pérez Antonio Bello 《Colloid and polymer science》2010,288(8):859-867
The phase transitions and the orientational behavior of liquid crystalline poly(triethylene glycol p,p′-bibenzoate) have been studied. The real-time synchrotron diffraction results indicate that, on cooling from the isotropic
melt, an orthogonal SmA mesophase is formed first, and later it is transformed into a tilted SmC mesophase. However, the SmA
mesophase is stable in a rather wide temperature interval, and the transformation into the SmC phase occurs at temperatures
close to the glass transition, so that not very high tilting angles are attained. The uniaxial deformation of the SmC mesophase
indicates that usual parallel orientation of the molecular axes in relation to the stretching direction is obtained at high
strain rates, while anomalous perpendicular orientation occurs at low deformation rates, with the smectic layers aligned with
the stretching direction and the molecular axes almost perpendicular. A mixture of the two types of orientation is observed
at intermediate rates, with rather interesting features. 相似文献
40.