| 1. |
- Ablikim, M., et al.
(författare)
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Measurements of (XcJ)-> K+K-K+K- decays
- 2006
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 642:3, s. 197-202
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Tidskriftsartikel (refereegranskat)abstract
- Using 14M psi(2S) events taken with the BESII detector, chi(cJ) -> 2(K+K-) decays are studied. For the four-kaon final state, the branching fractions are B(chi(c0,1,2) ->.2(K+K-)) = (3.48 +/- 0.23 +/- 0.47) x 10(-3), (0.70 +/- 0.13 +/- 0.10) x 10(-3), and (2.17 +/- 0.20 +/- 0.31) x 10(-3). For the phi K+K- final state, the branching fractions, which are measured for the first time, are B(chi(c0,1,2) -> phi K+K-) = (1.03 +/- 0.22 +/- 0.15) x 10(-3), (0.46 +/- 0.16 +/- 0.06) x 10(-3), and (1.67 +/- 0.26 +/- 0.24) x 10(-4). For the phi phi final state, B(chi(c0,2) -> phi phi) = (0.94 +/- 0.21 +/- 0.13) x 10(-3) and (1.70 +/- 0.30 +/- 0.25) x 10(-3).
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| 2. |
- Carninci, P, et al.
(författare)
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The transcriptional landscape of the mammalian genome
- 2005
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Ingår i: Science (New York, N.Y.). - : American Association for the Advancement of Science (AAAS). - 1095-9203 .- 0036-8075. ; 309:5740, s. 1559-1563
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Tidskriftsartikel (refereegranskat)abstract
- This study describes comprehensive polling of transcription start and termination sites and analysis of previously unidentified full-length complementary DNAs derived from the mouse genome. We identify the 5′ and 3′ boundaries of 181,047 transcripts with extensive variation in transcripts arising from alternative promoter usage, splicing, and polyadenylation. There are 16,247 new mouse protein-coding transcripts, including 5154 encoding previously unidentified proteins. Genomic mapping of the transcriptome reveals transcriptional forests, with overlapping transcription on both strands, separated by deserts in which few transcripts are observed. The data provide a comprehensive platform for the comparative analysis of mammalian transcriptional regulation in differentiation and development.
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| 3. |
- Molisch, Andreas, et al.
(författare)
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A low-cost time-hopping impulse radio system for high data rate transmission
- 2005
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Ingår i: Eurasip Journal on Applied Signal Processing. - 1110-8657. ; :3, s. 397-412
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Tidskriftsartikel (refereegranskat)abstract
- We present an efficient, low-cost implementation of time-hopping impulse radio that fulfills the spectral mask mandated by the FCC and is suitable for high-data-rate, short-range communications. Key features are (i) all-baseband implementation that obviates the need for passband components, (ii) symbol-rate (not chip rate) sampling, A/D conversion, and digital signal processing, (iii) fast acquisition due to novel search algorithms, and (iv) spectral shaping that can be adapted to accommodate different spectrum regulations and interference environments. Computer simulations show that this system can provide 110 Mbps at 7–10 m distance, as well as higher data rates at shorter distances under FCC emissions limits. Due to the spreading concept of time-hopping impulse radio, the system can sustain multiple simultaneous users, and can suppress narrowband interference effectively.
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| 4. |
- Liu, Y., et al.
(författare)
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Amorphous and nanocrystalline Al82Ni10Y8 alloy powder prepared by gas atomization
- 2005
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Ingår i: Intermetallics. - : Elsevier BV. - 0966-9795. ; 13:3-4, s. 393-398
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Tidskriftsartikel (refereegranskat)abstract
- An Al-10Ni-8Y (at.%) alloy was atomized by Ar gas and the morphology, microstructure, thermal stability, phase composition and microhardness of the as-atomized powder were investigated. Most of the powders are spherical in shape, but the surface morphology was different for powder of different size. The cross-section microstructure of powder with size below 15 Pro in diameter showed no detailed feature, indicating existence of amorphous phase or nanocrystalline structure. The as-atomized powder showed four distinct exothermic peaks when heated at 296, 340, 366 and 456 degrees C. The glass transition temperature T-g, crystallization temperature T-x, and the temperature interval of the supercooled liquid region Delta T-x(=T-x-T-g) were detected to be about 266, 288 and 22 degrees C. The Al82Ni10Y8 alloy powder exhibits a high Vickers hardness of 230.6, and shows great potential for structural application. (c) 2004 Elsevier Ltd. All rights reserved.
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| 5. |
- Liu, Y., et al.
(författare)
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Microstructural evolution of Al-Ni-Y powders an with different sizes
- 2005
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Ingår i: Zeitschrift fuer Metallkunde/Materials Research and Advanced Techniques. - 0044-3093. ; 96:1, s. 83-88
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Tidskriftsartikel (refereegranskat)abstract
- An Al-10Ni-8Y (at.%) alloy was atomized by Ar gas atomization in a close-coupled nozzle atomizer. The microstructure, phase composition, and thermal stability of the as-atomized powder were investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction analysis and differential scanning calorimetry. Activation energies for different crystallization reactions were calculated using both Kissinger and Ozawa methods. The supercooled liquid region DeltaT(x) (= T(x) - T(g), where T(x) and T(g) are crystallization onset temperature and glass transition temperature, respectively) was detected to be in the range of 14-24 K. Also presented were attempts to determine the critical particle size for amorphous structure.
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| 7. |
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| 8. |
- He, S. W., et al.
(författare)
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Cooling Rate Calculation of Non-Equilibrium Aluminum Alloy Powders Prepared by Gas Atomization
- 2009
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Ingår i: Xiyou Jinshu Cailiao Yu Gongcheng/Rare Metal Materials and Engineering. - 1002-185X. ; 38, s. 353-356
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Tidskriftsartikel (refereegranskat)abstract
- The cooling rate of aluminum alloy powders prepared by ultrasonic gas atomization process was calculated through the convection heat transfer principle. A simple and theoretical model is established, which can be expressed as vertical bar dT(d)/dt vertical bar =12/rho.C(p) . (T(d) - T(f)) . k(g)/d(2). The average cooling rates of Al-Ni-Ce-Fe-Cu alloy powders prepared by argon gas atomization and by helium gas atomization are about 10(4)similar to 10(7) K/s and 10(5)similar to 10(8) K/s, respectively. The critical cooling rate is calculated to be 3.74 x 10(5) K/s for Al-Ni-Ce-Fe-Cu alloy amorphous powders prepared by argon gas atomization. The cooling rates of gas-atomized powder particles estimated from secondary dendrite arm spacing are in consistence to those predicted from the theoretical model.
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| 10. |
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