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41.
C. Czekalla J. Lenzner A. Rahm T. Nobis M. Grundmann 《Superlattices and Microstructures》2007,41(5-6):347
In this paper, we report stimulated emission from a zinc oxide (ZnO) microcrystal grown by carbothermal evaporation observed by spatially resolved photoluminescence (PL) and high excitation spectroscopy (HES). 相似文献
42.
M. Diakonou C. Kourkoumelis L.K. Resvanis T.A. Filippas E. Fokitis C. Trakkas A.M. Cnops E.C. Fowler D.M. Hood R.B. Palmer D.C. Rahm P. Rehak I. Stumer C.W. Fabjan T. Fields D. Lissauer I. Mannelli W. Molzon W.J. Willis 《Physics letters. [Part B]》1980,91(2):296-300
We have measured direct photon production in pp collisions at the CERN intersecting storage rings for c.m. energies 31 < √s < 63 GeV and transverse momenta up to 9GeV/c, using segmented lead/liquid-argon calorimeters. The ratio of direct photon to π0 production is significantly larger than zero, starting at pT ≈ 4 GeV/c and increasing to values of about 0.4 at 9GeV/c. No significant √s dependence is seen. 相似文献
43.
J.H. Cobb S. Iwata R.B. Palmer D.C. Rahm I. Stumer C.W. Fabjan I. Mannelli K. Nakamura A. Nappi W. Struczinski W.J. Willis M. Goldberg N. Horwitz G.C. Moneti C. Kourkoumelis A.J. Lankford P. Rehak 《Physics letters. [Part B]》1977,68(1):101-104
The cross-section for J/ψ production in proton-proton collisions has been measured as a function of centre-of-mass energy at the CERN Intersecting Storage Rings by observing its decay into electron-positron pairs. This cross-section is found to rise by a factor of about six over the full centre-of-mass energy range from √s=23 to √s=63 GeV. Electrons resulting from this decay were identified by the use of liquid argon calorimeters and lithium foil transition radiators. Measurements of the energies of the electrons were obtained from the liquid argon calorimeters. 相似文献
44.
A.S. Carroll T.F. Kycia K.K. Li D.N. Michael P.M. Mockett D.C. Rahm R. Rubinstein 《Physics letters. [Part B]》1973,45(5):531-534
Measurements have been carried out of total cross sections of positive kaons on hydrogen and deuterium to a statistical precision of better than ± 0.1 mb for most points in the range of laboratory momentum from 410 to 1065 MeV/c in intervals of approximately 50 MeV/c. A very broad elastic structure in the I = 0 state is inferred. 相似文献
45.
C. Kourkoumelis L.K. Resvanis G. Voulgaris T.A. Filippas E. Fokitis A.M. Cnops J.H. Cobb S. Iwata R.B. Palmer D.C. Rahm P. Rehak S.D. Smith I. Stumer C.W. Fabjan T. Fields D. Lissauer I. Mannelli P. Mouzourakis A.J. Lankford 《Physics letters. [Part B]》1979,83(2):257-260
The inclusive production of π0 at large values of pT in pp collisions at the ISR has been studied. In this experiment the two photons are resolved and separately measured for pT values of up to 6 GeV/c, giving confidence that the desired signal has been separated from various backgrounds. 相似文献
46.
47.
Han Mo Jeong Ah Young Jo Mi Yeon Choi Man Jae Han Jae Young Jho 《Journal of Macromolecular Science: Physics》2013,52(5):789-799
The characteristics and performance of an ionic polymer–metal composite (IPMC), prepared with an anion‐exchange acrylic copolymer, was examined. The acrylic copolymer was synthesized by the radical copolymerization of fluoroalkyl methacrylate and 2‐(dimethyl amino)ethyl methacrylate(AMA). Effects of the AMA repeating unit's content in the copolymer and effects of the anion type present on the actuation of the IPMC were observed. The optimal content of 19.4 wt% AMA in the IPMC copolymer yielded the best actuation. The actuation also improved according to the type of anion present in the composite, in the following order: Br???4 ?. 相似文献
48.
Yang Shin Park Chang Hee Lee Baek Hui Kim Jongmee Lee Jae Woong Choi Kyeong Ah Kim Jeong Hwan Ahn Cheol Min Park 《Magnetic resonance imaging》2013
Purpose
The purpose of the study was to determine significant imaging features to differentiate between infiltrative hepatocellular carcinoma (HCC) and confluent fibrosis (CF) in liver cirrhosis using Gd-EOB-DTPA-enhanced 3-T magnetic resonance imaging.Material and methods
Nineteen infiltrative HCCs and eight CFs were included. We evaluated the difference in imaging findings and apparent diffusion coefficient (ADC) between the two entities. We compared T2-weighted image (WI) and hepatobiliary phase (HBP) in terms of the clarity of the lesion outer margin.Results
Seventeen infiltrative HCCs showed lobulated margin, while focal CFs showed either straight (n = 3) or irregular margins (n = 5) (P = .001). All infiltrative HCCs had intact or bulging contours, and all focal CFs showed capsular retraction (P = .001). Fourteen infiltrative HCCs and two focal CFs showed arterial enhancement (P = .035). The ADC of infiltrative HCCs was significantly lower than that of CFs (P = .001). Satellite nodules were noted in 10 infiltrative HCCs. In terms of outer margin clarity, infiltrative HCCs showed a more distinct margin on HBP than on T2-WI (P = .005), while these two sequences were not significantly different in focal CFs (P = 1.000).Conclusion
HBP improved the imaging characteristics of infiltrative HCC, allowing it to be distinguished from focal CF. Infiltrative HCC showed lower ADC values than focal CF. Lobular configuration, contour bulging, enhancement pattern, associated satellite nodules and portal vein thrombosis were still found to be highly suggestive MR findings for infiltrative HCC. 相似文献49.
50.
Schwartz BD Moore CJ Rahm F Hayes PY Kitching W De Voss JJ 《Journal of the American Chemical Society》2008,130(44):14853-14860
The volatile components of the mandibular gland secretion generated by the Giant Ichneumon parasitoid wasp Megarhyssa nortoni nortoni Cresson are mainly spiroacetals and methyl ketones, and all have an odd number of carbon atoms. A biosynthetic scheme rationalizing the formation of these diverse components is presented. This scheme is based on the results of incorporation studies using (2)H-labeled precursors and [(18)O]dioxygen. The key steps are postulated to be decarboxylation of beta-ketoacid equivalents, beta-oxidation (chain shortening), and monooxygenase-mediated hydroxylation leading to a putative ketodiol that cyclizes to spiroacetals. The generality of the role of monooxygenases in spiroacetal formation in insects is considered, and overall, a cohesive, internally consistent theory of spiroacetal generation by insects is presented, against which future hypotheses will have to be compared. 相似文献