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951.
By the aid of temperature- and magnetic-field-dependent Hall effect measurements, we have extracted the multi-carrier transport information in N-doped and N–In codoped p- ZnO thin films grown on Si substrates through mobility spectrum analysis. It is found that owing to the compensation between free electrons and holes, the two-dimensional hole gas from ZnO/Si interface layers becomes determinant and results in the high p-type conductivity and high hole mobility in the ZnO samples. Compared with N-doping, the N–In codoping introduces many In donors and increases acceptor incorporation, as well as enhancing the free hole mobility due to the short-range dipole-like scattering. 相似文献
952.
953.
Longlong YangPing Shen Qiaoli LinFeng Qiu Qichuan Jiang 《Applied Surface Science》2011,257(14):6276-6281
The isotherm wetting and spreading behaviors of the molten Cu-Cr alloys with 0.5, 1.0 and 2.0 at.% Cr on porous graphite substrates were investigated at 1373 K in a flowing Ar atmosphere using a modified sessile drop method. The wettability improves with increasing Cr content in the alloy as a result of phase transition from Cr3C2 to more wettable and metallic-like Cr7C3 developed at the interface. The spreading kinetics are controlled by the interfacial reaction in the early stage and the diffusion of Cr from the drop bulk to the triple junction in the later stage together with a transition in the intermediate stage. 相似文献
954.
Shen Honglong Yang Xiaoqiang Song Juanjuan Gao Haiwen Wu Zongdeng Yu Jia Lei Wu Yang Jiazhi He Guangyu Hao Qingli 《Journal of Solid State Electrochemistry》2022,26(2):353-363
Journal of Solid State Electrochemistry - Long-cycle stability and high-energy density are big challenges for developing high-performance hybrid supercapacitor (HSC) electrode materials. In this... 相似文献
955.
956.
D.H. Shen A. Berlinger E. Nold W. Lai G.M. Luo 《Applied Physics A: Materials Science & Processing》1999,68(4):425-428
Received: 13 August 1998 / Published online: 10 February 1999 相似文献
957.
958.
J. H. Rohling J. Shen C. Wang J. Zhou C. E. Gu 《The European physical journal. Special topics》2008,153(1):111-113
In this work, an effective gas diffusion coefficient of a
porous medium was measured using photothermal deflection (PD) technique. An
in-house made Loschmidt diffusion cell with a photothermal-deflection probe
were employed to measure the effective gas diffusion coefficient of a gas
diffusion layer (GDL) with a porosity ε ≈ 0.7. The concentration
evolutions of CO2 in O2 with and without the GDL were measured,
respectively, using a transverse normal PD technique. The concentration
variations were used to deduce the gas diffusion coefficients in the
presence and absence of the GDL by solving mass diffusion equations. The
effective gas diffusion coefficient of the GDL was calculated from the
diffusion coefficients using a model of an equivalent resistance to
diffusion and found to be 4.39 × 10-6 m2s-1,
demonstrating that PD technique can be employed to determine the effective
gas diffusion coefficient of a porous medium. 相似文献
959.
Thermal-annealing has been widely used in modulating the oxygen content of manganites. In this work, we have studied the effect of annealing on the transport properties and magnetoresistance of junctions composed of a La0.9Ca0.1MnO3+6 film and a Nb-doped SrTiO3 substrate. We have demonstrated that the magnetoresistance of junctions is strongly dependent on the annealing conditions: Prom the junction annealed-in-air to the junction annealedin-vacuum, the magnetoresistance near 0-V bias can vary from ~-60% to N~0. A possible mechanism accounting for this phenomenon is discussed. 相似文献
960.
Superconducting La1.937Sr0.063CuO4 crystals grown by the travelling-solvent floating-zone technique were thermally treated under various temperatures and oxygen pressures for moderately adjusting the oxygen content. The response of intrinsic electronic property of the crystals to the change of hole density in La2-xSrxCuO4 in the vicinity of the magic doping of x= 1/16 (= 0.0625) is studied in detail by magnetic measurements under various fields up to 1 T. It is found that when the superconducting critical temperature (Tc) increases with the oxygen content, there appears also a new subtle electronic state that can be detected from the differential curves of diamagnetic susceptibility dx/dT of the crystal sample. In contrast with the intrinsic state, the new subtle electronic state is very fragile under the magnetic fields. Our results indicate that a moderate change in oxygen doping does not significantly modify the intrinsic electronic state originally existing at the magic doping level. 相似文献