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Flexible Cu2ZnSn(S,Se)4 (CZTSSe) solar cells have wide application prospects. N-type window layers and contact among the layers have an important effect on the properties of flexible CZTSSe solar c...

Zn(O,S) is an attractive alternative to CdS as a buffer layer of Cu2ZnSnS4 (CZTS)-based solar cell due to its higher bandgap and environmental friendliness. In this work, CZTS solar cell with a structure of CZTS/Zn(O,S)/Al:ZnO was simulated by Solar Cell Capacitance Simulator (SCAPS). The impacts of thickness and acceptor concentration of CZTS, thickness and donor concentration of Zn(O,S) and operating temperature on the performance of CZTS solar cells were investigated. It has been obtained that the optimum thickness of CZTS is between 2000 and 3000 nm and that of Zn(O,S) is about 50 nm. The suitable doping concentrations of CZTS and Zn(O,S) layers are around 1016 and 1017 cm−3, respectively. The temperature coefficient of efficiency is about −0.023 %/K in the CZTS solar cell. All these simulation results will provide some important guidelines for fabricating high efficient CZTS solar cells.

[EN] Urban morphology has been studied extensively in western countries, while the related researches had been carried out late in China and the researches on urban morphology evolution characteristics of China are rare. Scanty case studies like Pingyao showed that the characteristics of urban form and its evolutionary process of China was different from the western. This paper review the existing researches and take Shangqiu as a case city to study urban morphology evolution characteristics of Chinese cities, preliminary analyze China s special social and economic characteristics as well as its urban morphology process from the double fringe belts, plot and block patterns of Shangqiu. Through the research on the evolution of Shangqiu s urban form, this paper aims to preliminary delimit the morphological period of Shangqiu, explore the evolution mechanism of Shangqiu, summarize evolutionary characteristics of Chinese cities and reflect urban morphological approaches in western academic system.

In this paper, we propose a novel structural correlation filter combined with a multi-task Gaussian particle filter (KCF-GPF) model for robust visual tracking. We first present an assemble structure where several KCF trackers as weak experts provide a preliminary decision for a Gaussian particle filter to make a final decision. The proposed method is designed to exploit and complement the strength of a KCF and a Gaussian particle filter. Compared with the existing tracking methods based on correlation filters or particle filters, the proposed tracker has several advantages. First, it can detect the tracked target in a large-scale search scope via weak KCF trackers and evaluate the reliability of weak trackers\rq decisions for a Gaussian particle filter to make a strong decision, and hence it can tackle fast motions, appearance variations, occlusions and re-detections. Second, it can effectively handle large-scale variations via a Gaussian particle filter. Third, it can be amenable to fully parallel implementation using importance sampling without resampling, thereby it is convenient for VLSI implementation and can lower the computational costs. Extensive experiments on the OTB-2013 dataset containing 50 challenging sequences demonstrate that the proposed algorithm performs favourably against 16 state-of-the-art trackers., 10 pages. arXiv admin note: text overlap with arXiv:1703.05020 by other authors

SnS/CdS heterojunction is a promising system for photovoltaic application. SnS thin films were thermally evaporated onto CdS/ITO coated glass substrates. The structure of the device was glass/ ITO/CdS/SnS/In/Ag and I-V curves of the fabricated devices were measured under dark and illuminated conditions, respectively. We discussed the relationship of the thickness and annealing temperature of CdS buffer layers with the performance of SnS/CdS heterojunctions. The optimum thickness and annealing temperature of the CdS buffer layers were 50 nm and 350°C, respectively. The best device had a conversion efficiency of 0.0025%.

Zinc oxide (ZnO) nanowires were synthesized on bare silicon substrates and sputtered-ZnO seeded substrates by hydrothermal method in mixture solution of zinc acetate and cooper acetate. The nanowires are in random alignment on the bare substrate, while the vertically aligned nanowires with a c-axis (002) preferential orientation are available on the ZnO seeded substrate. The near band-edge UV emission peaks on the PL spectra could be seen, indicating a good crystal structure of ZnO. With the increase of cooper concentration, the intensity of UV peak decreases but that of green emission peak enhances, which means the defects inside nanowires could be increased by the cooper additive. For the Raman measurement, there is 437 cm-1 centered peak for each sample, indicating that nanowires are perfect hexagonal wurtzite structure. In the Raman spectra, the 581.4 cm-1 centered peak attributed to oxygen vacancies could also be seen for the sample with cooper additive.

A liquid-phase cycloaddition reaction near ambient temperature involving dimethyl acetylenedicarboxylate (DMAD) and cyclopentadiene (CP) as reactants was measured using a conventional Fourier transform infrared (FT-IR) spectrometer with an emission accessory. Two semi-batch experiments were performed and a total of 55 spectra were collected using a DTGS detector. Band-target entropy minimization (BTEM), a pure component spectral reconstruction technique, was applied to analyze the data set to retrieve the pure component emission spectrum from the reaction system. The estimated emission spectra of the solvent chloroform, DMAD, CP, and product, namely dimethyl bicyclo[2.2.1]-2,5-heptadiene-2,3-dicarboxylate, were all reconstructed with rather good quality. The estimated emission spectra are similar to independent FT-IR spectra of the same cycloaddition reaction. Using a least squares fit, the relative concentration profiles of the species are obtained. Because this appears to be the first time that a liquid-phase reaction has been monitored by infrared emission spectroscopy, further improvements and opportunities for general multi-phase liquid reaction monitoring are discussed.

Thermal emission spectral data sets were collected for a thin solid film (parafilm) and a thin liquid film (isopropanol) on the interval of 298–348 K. The measurements were performed using a conventional Fourier transform infrared (FT-IR) spectrometer with external optical bench and in-house-designed emission cell. Both DTGS and MCT detectors were used. The data sets were analyzed with band-target entropy minimization (BTEM), which is a pure component spectral reconstruction program. Pure component emissivities of the parafilm, isopropanol, and thermal background were all recovered without any a priori information. Furthermore, the emissivities were obtained with increased signal-to-noise ratios, and the signals due to absorbance of thermal radiation by gas-phase moisture and CO2 were significantly reduced. As expected, the MCT results displayed better signal-to-noise ratios than the DTGS results, but the latter results were still rather impressive given the low temperatures used in this study. Comparison is made with spectral reconstruction using the orthogonal projection approach–alternating least squares (OPA-ALS) technique. This contribution introduces the primary equation for emission spectral reconstruction using BTEM and discusses some of the unusual characteristics of thermal emission and their impact on the analysis.