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111.
H. Pedersen S. Leone A. Henry V. Darakchieva P. Carlsson A. Gällström E. Janzén 《固体物理学:研究快报》2008,2(4):188-190
200 µm thick 4H‐SiC epilayers have been grown by chloride‐based chemical‐vapor deposition using methyltrichlorosilane (MTS) as single precursor. The very high crystalline quality of the grown epilayer is demonstrated by high resolution X‐Ray Diffraction rocking curve with a full‐width‐half‐maximum value of only 9 arcsec. The high quality of the epilayer is further shown by low temperature photoluminescence showing strong free exciton and nitrogen bound exciton lines. The very high crystalline quality achieved for the thick epilayer grown in just two hours at 1600 °C suggests that MTS is a suitable precursor molecule for SiC bulk growth. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
112.
Malmberg JN Carlsson AH Anderson D Lisak M Ostrovskaya EA Kivshar YS 《Optics letters》2000,25(9):643-645
We address the problem of the existence and stability of vector spatial solitons formed by two incoherently interacting optical beams in bulk Kerr and saturable media. We identify families of (2+1)-dimensional two-mode self-trapped beams, with and without a topological charge, and describe their properties analytically and numerically. 相似文献
113.
Ohne Zusammenfassung 相似文献
114.
115.
Ohne Zusammenfassung 相似文献
116.
A. Garton D. J. Carlsson D. M. Wiles 《Journal of polymer science. Part A, Polymer chemistry》1978,16(1):33-40
The γ-initiated oxidation and presensitized photooxidation of polypropylene films and fibers are shown to be insensitive to sample thickness (if <150 μm) and a range of morphological parameters such as molecular orientation (in drawn samples) and fibrillar and void content. The relevance of these observations is discussed in the light of the many previous assertions as to the influence of morphological effects on oxidation rates. The γ-initiated oxidation was studied in preference to conventional thermal or photoinitiated oxidation because of the greater control over the rate of radical production available by this method. 相似文献
117.
The homogeneity range of Fe2P has been determined using the annealing and quenching technique in combination with X-ray powder diffraction methods. The iron-rich limit is invariant at Fe2.00P for temperatures up to 1150°C. The phosphorus-rich limit varies from Fe2.00P at low temperatures to Fe1.94P at 1100°C. The crystal structure of Fe2.00P has been refined from X-ray diffraction data obtained by single-crystal diffractometry. The thermal vibrations differ appreciably in magnitude for the two non-equivalent types of iron atom. 相似文献
118.
G. Warren P. Gregory P. Mason H. Muirhead R. Carlsson G. Ekspong S.O. Holmgren S. Nilsson R. Stenbacka Ch. Walck 《Nuclear Physics B》1977,130(3):367-387
We consider the annihilation mechanism in the antiproton momentum range 2.5 to 9.1 GeV/c. Techniques for identifying a “leading pion” are discussed. The annihilation is examined as a quasi two-body process, and the properties of the “leading pion” and the remaining multi-pion “cluster” are presented. A simple parametrization is found to reproduce satisfactorily several features of the data. 相似文献
119.
K. Elihn F. Otten M. Boman P. Heszler F.E. Kruis H. Fissan J.-O. Carlsson 《Applied Physics A: Materials Science & Processing》2001,72(1):29-34
Iron-containing nanoparticles were made by laser-assisted (ArF excimer laser, λ=193 nm) photolytic dissociation of ferrocene
(Fe(C5H5)2 or FeCp2) in argon and an oxygen/argon gas mixture. The particle-size distributions were obtained on-line by using differential mobility
analysers (DMAs) and were found to be log-normal with a geometric standard deviation of 1.85. In argon, particle sizes between
3 and 100 nm were generated. The volumes of these particles were found to increase linearly with the increased repetition
rate, fluence and beam size of the laser. These observations are explained on the basis of the residence-time approach model.
Received: 23 November 1999 / Accepted: 19 September 2000 / Published online: 22 November 2000 相似文献
120.
Elisabeth Odin Yvonne Wettergren Göran Carlsson Bengt Gustavsson 《Biomedical chromatography : BMC》2013,27(4):487-495
A liquid chromatography electrospray ionization tandem mass spectrometry (LC‐MS/MS) method has been developed for the determination of 5,10‐methylenetetrahydrofolate (methyleneTHF), tetrahydrofolate (THF) and 5‐methyltetrahydrofolate (methylTHF) in colorectal mucosa and tumor tissues. The folate extraction method includes homogenization, heat and folate conjugase treatment to hydrolyze polyglutamyl folate to monoglutamyl folate. Before analysis on LC‐MS/MS, simple and fast sample purification with ultrafiltration (molecular weight cut‐off membrane, 10 kDa) was performed. Folates were detected and quantified using positive electrospray. The method described in the present paper was successfully applied to determine the level of three folate monoglutamates in mucosa and tumor samples from 77 colorectal cancer patients, starting from a limited amount of tissue. The results showed that the LC‐MS/MS method has a great advantage over other previously used methods because of its high sensitivity and selectivity. Significantly higher levels of methyleneTHF and THF were found in tumor compared with matched mucosa tissues. Folate levels in adjacent mucosa were associated with tumor location, age and gender. The correlation between folate levels and tumor site further strengthens the fact that development of right‐ and left‐sided tumors follows different pathways. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献