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991.
Effect of emitter layer doping concentration on the performance of silicon thin film heterojunction solar cell 下载免费PDF全文
A novel type of n/i/i/p heterojunction solar cell with a-Si:H(15 nm)/a-Si:H(10 nm)/ epitaxial c-Si(47 μm)/epitaxial c-Si(3 μm) structure is fabricated by using the layer transfer technique, and the emitter layer is deposited by hot-wire chemical vapour deposition. The effect of the doping concentration of emitter layer Sd (Sd=PH3/(PH3+SiH4+H2)) on the performance of the solar cell is studied by means of current density-voltage and external quantum efficiency. The results show that the conversion efficiency of the solar cell first increases to a maximum value and then decreases with Sd increasing from 0.1% to 0.4%. The best performance of the solar cell is obtained at Sd = 0.2% with an open circuit voltage of 534 mV, a short circuit current density of 23.35 mA/cm2, a fill factor of 63.3%, and a conversion efficiency of 7.9%. 相似文献
992.
Qiaoli Yue Lijun Sun Tongfei Shen Xiaohong Gu Shuqiu Zhang Jifeng Liu 《Journal of fluorescence》2013,23(6):1313-1318
In the present work, gold nanocluster (GNC) induced by bovine serum albumin (BSA) was synthesized as a novel fluorescence probe to detect nitrite (NO2 ?) sensitively and selectively. The fluorescence of GNC was found to be quenched effectively by NO2 ?. Under the optimum conditions, it was found that the change of fluorescence intensity was proportional with the concentration of NO2 ? in the linear range of 0.1–50 μM (R?=?0.9990), with a detection limit (S/N?=?3) of 30 nM. The absorption spectroscopy, circular dichroism (CD), and X-ray photoelectron spectroscopy (XPS) studies were employed to discuss the quenching mechanism. In addition, the present approach was successfully applied in real water samples. 相似文献
993.
Oscillation of coercivity between positive and negative in MnxGe1-x:H ferromagnetic semiconductor films 下载免费PDF全文
Amorphous MnxGe1-x :H ferromagnetic semiconductor films prepared in mixed Ar with 20% H2 by magnetron cosputtering show global ferromagnetism with positive coercivity at low temperatures. With increasing temperature, the coercivity of MnxGe1-x :H films first changes from positive to negative, and then back to positive again, which was not found in the corresponding MnxGe1-x and other ferromagnetic semiconductors before. For Mn0.4Ge0.6 :H film, the inverted Hall loop is also observed at 30 K, which is consistent with the negative coercivity. The negative coercivity is explained by the antiferromagnetic exchange coupling between the H-rich ferromagnetic regions separated by the H-poor non-ferromagnetic spacers. Hydrogenation is a useful method to tune the magnetic properties of MnxGe1-x films for the application in spintronics. 相似文献
994.
Using the classical Mie scattering theory,we compute the energy density of an arbitrary partial wave(e.g.,the nth order) and then determine that the interaction between an incident planar wave and a sphere of radius a is the one between the sphere and those partial waves the order of which satisfies n≤ka.We also provide a simple expression to describe the diffracted wave in which the angle-dependent functions are employed.The difference between the accurate and the approximate expressions is demonstrated by numerical calculation. 相似文献
995.
采用Sn自熔剂法制备了具有n型传导的VIII型Ba8Ga16 xGexSn30(0 x 1.0)单晶笼合物,并对其结构和热电特性进行研究.研究结果表明:Ge在单晶中的实际含量较少,随着掺杂量的增加样品的晶格常数略有减小,Ge掺杂后样品的载流子浓度较掺杂前低,迁移率增加;所有样品的Seebeck系数均为负值,且绝对值较未掺杂样品低,但Ge掺杂后样品的电导率提高了62%;x=0.5的样品在500 K附近取得最大ZT值1.25. 相似文献
996.
本文在获得精确的7.5mol%Nb:KTP晶体的Sellmeier主折射率色散方程的基础上,计算7.5mol%Nb:KTP晶体对1.0642μm和1.3188μmNd:YAG激光的倍频和和频的型相位匹配曲线.通过研究KTP和7.5mol%Nb:KTP晶体的主折射率,双折射率和相位匹配,可以看出Nb掺入KTP晶体后产生的折射率和双折射率的色散和各向异型的变化是引起KTP晶体相位变化的根本原因. 相似文献
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Iron Oxide Nanoparticles: Facile Synthesis of Gd(OH)3‐Doped Fe3O4 Nanoparticles for Dual‐Mode T1‐ and T2‐Weighted Magnetic Resonance Imaging Applications (Part. Part. Syst. Charact. 10/2015) 下载免费PDF全文