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41.
Andriy V. Kozytskiy Oleksandr L. Stroyuk Stepan Ya. Kuchmiy Volodymyr M. Dzhagan Dietrich R. T. Zahn Mykola A. Skoryk Vyacheslav O. Moskalyuk 《Journal of Materials Science》2013,48(21):7764-7773
Nanocrystalline ITO/ZnO films formed by porous zinc oxide microplatelets 1–3 μm in size and 100–200 nm in thickness, which consist of 30–50 nm ZnO crystallites, were sensitized to visible light by Cd x Zn1?x S nanocrystals deposited using the method of successive ionic layer adsorption and reaction (SILAR). The composition of Cd x Zn1?x S nanocrystals as well as the dependence between molar Cd(II) fraction in the films and the ratio of cadmium and zinc nitrate concentrations in solutions used for the SILAR procedure were determined by a combination of electron, Raman, and energy-dispersive X-ray spectroscopies. The photovoltage observed at illumination of the ITO/ZnO/Cd x Zn1?x S heterostructures by white light (λ >400 nm) in aqueous Na2S solution increases with a decrease of Cd(II) content proportionally to an increment in the conduction band potential of the Cd x Zn1?x S nanocrystals. The photocurrent density normalized to the light absorbance of the ITO/ZnO/Cd x Zn1?x S films increases by a factor of around four when the conduction band potential of Cd x Zn1?x S nanocrystals grows by 220 mV as a result of Cd(II) fraction changing from 1.0 to 0.62–0.67. The results show that Cd x Zn1?x S solid solutions are more advantageous sensitizers for the short-wavelength part of the sensitivity window of the liquid-junction solar cells (400–450 nm) than conventionally used cadmium sulfide. 相似文献
42.
Mykola Beshley Natalia Kryvinska Halyna Beshley Orest Kochan Leonard Barolli 《计算机、材料和连续体(英文)》2022,70(1):19-35
In this paper, we developed a new customizable low energy Software Defined Networking (SDN) based Internet of Things (IoT) platform that can be reconfigured according to the requirements of the target IoT applications. Technically, the platform consists of a set of low cost and energy efficient single-board computers, which are interconnected within a network with the software defined configuration. The proposed SDN switch is deployed on Raspberry Pi 3 board using Open vSwitch (OvS) software, while the Floodlight controller is deployed on the Orange Pi Prime board. We firstly presented and implemented the method for measuring a delay introduced by each component of the IoT infrastructure, ranging from the sensor, the core of SDN, the IoT broker, to an IoT subscriber. Thus, we presented the approach for estimating energy efficiency for SDN based IoT platform proportional to the traffic. The experiments carried out on a real SDN topology based on single-board computers show that our approach not only saves up to 53.56% of energy at low traffic intensity, but also provides QoS guarantee for IoT applications. 相似文献
43.
针对现有适用于单天线接收机的干扰抑制技术难以为周期调频(PFM)干扰和卫星导航信号提供足够分离度,导致消除干扰成分时卫星导航信号损伤较大的问题,该文提出一种基于周期截断数据矩阵奇异值分解的干扰抑制方法。利用调频干扰信号的周期性把分散在较大带宽的能量集中到重排数据中几个甚至单个频点;进而采用奇异值分解(SVD)将干扰与期望信号映射进不同的投影子空间以消除干扰成分。仿真结果表明该方法可以降低在剔除干扰时卫星导航信号损失,提升卫星导航接收机对抗宽带周期调频干扰的能力。 相似文献
44.
The real contact between solids is modeled at the molecular scale, and the results are presented. Adhesion, real contact area, and approach of the surfaces are evaluated with the help of scanning, tunneling, and atomic force microscope imaging of the surfaces. 相似文献
45.
V. P. Borshchev I. V. Zhukov O. P. Mel'nikov M. I. Rozhdestvenskii Yu. M. Cherkashov E. V. Burlakov V. M. Kvator E. K. Gorbunov V. I. Lebedev A. N. Fursov V. G. Shevchenko V. Yu. Kuznetsov Yu. I. Mironov V. I. Romanenko V. I. Ryakhovskikh 《Atomic Energy》2003,95(6):856-861
It is shown that radiation doping of silicon and the production of medical and industrial radioisotopes in the reactors at the Leningrad nuclear power plant are possible and safe. The production of cobalt with specific activity ~100 Ci/g in an RBMK-1000 reactor is studied. Some promising developments for improving the quality of the radioisotopes produced are described. It is shown that the production volumes can be increased by linking up other nuclear power plants with RBMK reactors into the production chain. 相似文献
46.
S. P. Gorbunov V. I. Krasov V. L. Paperny Yu. V. Korobkin I. V. Romanov 《Technical Physics Letters》2005,31(11):989-992
The contributions of fast and slow ion components to the average mass transfer rate in the cathode plasma jet of a low-inductance
vacuum spark have been determined using time-of-flight measurements. The total mechanical momentum of the cathode plasma jet
has been found using the ballistic pendulum technique. The coefficient γ of ion erosion of a cathode material was evaluated
in the range of discharge current amplitudes 3–13 kA and the discharge current buildup rates 4 × 109 − 1.5 × 1010 A/s. The γ value exhibits small variations in the indicated range of discharge parameters and is close to the values known
for vacuum arcs. 相似文献
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