| 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. |
- He, Sailing, et al.
(författare)
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Abnormal guiding and filtering properties for some composite structures of right/left-handed metamaterials
- 2005
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Ingår i: Asia-Pacific Microwave Conference Proceedings, APMC. - 078039433X
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Konferensbidrag (refereegranskat)abstract
- We study some abnormal guiding and filtering properties for some multi-layered structures consisting of right/left-handed metamaterials. The extremely slow propagation of guided waves in a slab waveguide with a left-handed material substrate is studied. Resonating and notch filters based on some composite right/left-handed (CRLH) transmission lines are also proposed.
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| 3. |
- Hou, Yuanyuan, et al.
(författare)
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Pressure-induced polymerization of nano- and submicrometer C60 rods into a rhombohedral phase
- 2006
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Ingår i: Chemical Physics Letters. - : Elsevier BV. - 0009-2614. ; 423:1-3, s. 215-219
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Tidskriftsartikel (refereegranskat)abstract
- C-60 rods with nano- and submicrometer dimensions were polymerized at 4.5 GPa and 973 K. Raman spectroscopy showed that the material transformed into a rhombohedral polymeric structure under high pressure and high temperature (HPHT) conditions. The HPHT polymerized samples keep the original rod shape. The position dependence of photoluminescence (PL) spectra have been studied on the rhombohedral polymer C60 rods at room temperature. The intensity of the 1.74 eV peak from the rhombohedral phase varies systematically between the edge of and the middle of the rod. Our results indicate that the 1.74 eV peak originates from surface defects.
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| 4. |
- Li, J. S., et al.
(författare)
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A novel notch filter utilizing a composite right/left-handed transmission line
- 2006
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Ingår i: Microwave and optical technology letters (Print). - : Wiley. - 0895-2477 .- 1098-2760. ; 48:3, s. 626-628
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Tidskriftsartikel (refereegranskat)abstract
- A novel notch filter based on a composite right/left-handed (CRLH) transmission line is proposed. The proposed CRLH transmission line is different-from a conventional CRLH transmission line. The novel notch filter has a large notch depth, very small loss in the passband, and very sharp transitions at the two edges of the stop-band.
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| 5. |
- Ren, Tie-Zhen, et al.
(författare)
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Single crystal manganese oxide hexagonal plates with regulated mesoporous structures
- 2008
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Ingår i: Microporous and Mesoporous Materials. - : Elsevier BV. - 1387-1811 .- 1873-3093. ; 112:03-jan, s. 467-473
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Tidskriftsartikel (refereegranskat)abstract
- Porous hexagonal plates of manganese oxides are prepared by a simple hydrothermal method from metal Mn foils/powders and manganese acetate precursors tinder basic conditions. The oriented aggregation-based assembly of the nanoparticles of mixed feitknechtite and hausmannite phases gave rise to well-defined hexagonal nanoplates with irregular mesopores of similar to 5 nm in size. The hexagonal plate-like morphology was retained after calcination, and mesoporous single-crystalline Mn5O8 and alpha-Mn2O3 plates were obtained after calcinations at 400 and 700 degrees C, respectively. The interior mesopores in each plate were enlarged with the increase of calcination temperature, and turned out to be regular-shaped, i.e. polyhedral or even well-defined rectangular. Furthermore, 700 degrees C-calcination led to the fusion of nanocrystals into structurally uniform alpha-Mn2O3 crystals of hexagonal plates with regular-shaped mesoporous structure. X-ray diffraction and electron diffraction, scanning and transmission electron microscopy, X-ray energy dispersive spectroscopy, and nitrogen sorption analysis were employed to characterize these porous nanoplates. Such mesoporous hexagonal nanoplates of manganese oxides with high crystallinity may have many applications.
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| 6. |
- Zou, Y., et al.
(författare)
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Compact coplanar waveguide low-pass filter using a novel electromagnetic bandgap structure
- 2006
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Ingår i: 7th International Symposium on Antennas, Propagation and EM Theory, Proceedings. - 1424401623 - 9781424401628 ; , s. 1039-1042
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Konferensbidrag (refereegranskat)abstract
- In the present paper, a new electromagnetic bandgap (EBG) structure is proposed to design and fabricate low-pass filters on coplanar waveguide (CPW). Using the novel EBG structure, the filter prototypes exhibit sharp cutoff and low insertion loss in the passband. An equivalent lumped L-C circuit mode is introduced to describe the proposed EBG structure, which manifests an elliptic-function low-pass frequency response. Using only three units of this novel EBG cell, a compact low-pass filter device has been fabricated, which achieved sharp cutoff and deep attenuation levels on the stop band. The measured results showed consistency with the simulation using the method of momentum (MoM).
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