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排序方式: 共有118条查询结果,搜索用时 15 毫秒
61.
62.
Improved performance of polymer solar cells by using inorganic,organic, and doped cathode buffer layers 下载免费PDF全文
The interface between the active layer and the electrode is one of the most critical factors that could affect the device performance of polymer solar cells. In this work, based on the typical poly(3-hexylthiophene):[6,6]-phenyl C61-butyric acid methyl ester(P3HT:PCBM) polymer solar cell, we studied the effect of the cathode buffer layer(CBL) between the top metal electrode and the active layer on the device performance. Several inorganic and organic materials commonly used as the electron injection layer in an organic light-emitting diode(OLED) were employed as the CBL in the P3HT:PCBM polymer solar cells. Our results demonstrate that the inorganic and organic materials like Cs_2CO_3, bathophenanthroline(Bphen), and 8-hydroxyquinolatolithium(Liq) can be used as CBL to efficiently improve the device performance of the P3HT:PCBM polymer solar cells. The P3HT:PCBM devices employed various CBLs possess power conversion efficiencies(PCEs) of 3.0%–3.3%, which are ca. 50% improved compared to that of the device without CBL. Furthermore, by using the doped organic materials Bphen:Cs_2CO_3 and Bphen:Liq as the CBL, the PCE of the P3HT:PCBM device will be further improved to 3.5%, which is ca. 70% higher than that of the device without a CBL and ca. 10% increased compared with that of the devices with a neat inorganic or organic CBL. 相似文献
63.
This paper presents a novel microstrip feedline structure to introduce an extra and controllable transmission zero(TZ)with high rejection for a narrowband filter. This structure loads a reconfigurable capacitor at the end of the input feedline without changing the main structure of the filter. The capacitor is recognized by a 2-bit inter-digital capacitor array. The asymmetrical microstrip feedline structure is suitable for multiple-pole filter designs. A low-loss six-pole high-temperature superconducting bandpass filter with a reconfigurable TZ is designed and fabricated. The center frequency of the filter is 5.22 GHz with TZ at the lower stopband. The TZ can be tuned among four different states. The out-of-band rejection at the TZ frequency is higher than 90 d B, and the insertion loss is lower than 0.92 d B. The measured results are consistent with the simulations. 相似文献
64.
Superconducting tunable filter with constant bandwidth using coplanar waveguide resonators 下载免费PDF全文
In this paper we propose a two-pole varactor-tuned superconducting filter using coplanar waveguide(CPW) spiralin-spiral-out(SISO) resonators. Novel internal and external coupling structures are introduced to meet the requirements for a tunable filter with a constant absolute bandwidth. The fabricated device has a frequency tuning range of 14.4%at frequencies ranging from 274.1 MHz to 317.7 MHz, a 3-d B bandwidth of 5.14 ± 0.06 MHz, and an insertion loss of0.08 d B–0.70 d B. The simulated and measured results are in excellent agreement with each other. 相似文献
65.
A scheme of surface manipulation and control of polar molecules is proposed, which combines three tools of electrostatic velocity filtering, bunching, and storing. In the scheme, a slow molecular beam is produced from an effusive beam by surface velocity filtering. Then the velocity spread of the slow molecular beam is compressed by a buncher consisting of a series of electrodes. Following that the molecular beam with a narrow velocity spread is stored in a storage ring. Using ND_3 molecule as a tester, the feasibility of our scheme is analyzed theoretically and verified via numerical simulations that cover all three manipulation processes. The results show that cold molecular samples can be prepared from a thermal gas reservoir and stored in the storage ring with more than 10 round trips. Our combined scheme facilitates the production and manipulation of polar molecules, offering new opportunities for basic research and intriguing applications such as quantum information science and cold collisions. 相似文献
66.
67.
Fine-tuning the thicknesses of organic layers to realize high-efficiency and long-lifetime blue organic light-emitting diodes 下载免费PDF全文
By using p-bis(p-N,N-diphenyl-aminostyryl)benzene doped 2-tert-butyl-9,10-bis-β-naphthyl)-anthracene as an emitting layer,we fabricate a high-efficiency and long-lifetime blue organic light emitting diode with a maximum external quantum efficiency of 6.19% and a stable lifetime at a high initial current density of 0.0375 A/cm2.We demonstrate that the change in the thicknesses of organic layers affects the operating voltage and luminous efficiency greater than the lifetime.The lifetime being independent of thickness is beneficial in achieving high-quality full-colour display devices and white lighting sources with multi-emitters. 相似文献
68.
血液灌流用胆红素吸附剂的吸附性能研究 总被引:4,自引:1,他引:3
胆红素是一种内源性毒素.急性肝损伤时,体内胆红素的排泄受到阻碍.如何能有效地排除高浓度的胆红素,引起了各国学者的高度重视[1].文献[2,3]报道,在血液净化疗法治疗高胆红素血症中,当胆红素吸附剂上含有氨基阳离子时,可以提高其对胆红素的吸附量. 相似文献
69.
Two types of highly efficient electrostatic traps for single loading or multi-loading of polar molecules 下载免费PDF全文
Two novel electrostatic traps named octopole-based disk electrostatic trap(ODET)and tubular-based disk electrostatic trap(TDET)are proposed for trapping cold polar molecules in low-field-seeking states.Using MgF as the target molecule,single loading and multi-loading methods are numerically simulated with varied incident velocities of slow molecular beams in the two types of traps,respectively.In ODET,with an incident velocity of 10 m/s,a highest loading efficiency of 78.4% or 99.9% has been achieved under the single loading or multi-loading operation mode.In TDET,with an incident velocity of 11 m/s,a highest loading efficiency of 81.6% or 106.5% has been achieved using the two loading methods,respectively.With such high loading efficiencies,the trapped cold molecules can be applied in the researches of cold collisions,high precision spectroscopy,and precision measurements.Especially,together with a blue-detuned hollow beam,the new electrostatic traps proposed here offer a new platform for the following gradient-intensity cooling of MgF molecules,which may provide a new way to produce high density ultracold molecules. 相似文献
70.
Based on Fermat’s principle and the automatic optimization mechanism in the propagation process of light,an optimal searching algorithm named light ray optimization is presented,where the laws of refraction and reflection of light rays are integrated into searching process of optimization.In this algorithm,coordinate space is assumed to be the space that is full of media with different refractivities,then the space is divided by grids,and finally the searching path is assumed to be the propagation path of light rays.With the law of refraction,the search direction is deflected to the direction that makes the value of objective function decrease.With the law of reflection,the search direction is changed,which makes the search continue when it cannot keep going with refraction.Only the function values of objective problems are used and there is no artificial rule in light ray optimization,so it is simple and easy to realize.Theoretical analysis and the results of numerical experiments show that the algorithm is feasible and effective. 相似文献