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71.
Ren Wuyang Li Handong Gao Lei Li Yong Zhang Zhongyang Long Chengjia Ji Haining Niu Xiaobin Lin Yuan Wang Zhiming 《Nano Research》2017,10(1):247-254
Nano Research - Thermal transport in superlattices is governed by various phonon-scattering processes. For extracting the phonon-scattering contribution of hetero-interfaces in chalcogenide... 相似文献
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Tensile Strength Evolution and Damage Mechanisms of Al–Si Piston Alloy at Different Temperatures 下载免费PDF全文
Meng Wang Jianchao Pang Yu Qiu Haiquan Liu Shouxin Li Zhefeng Zhang 《Advanced Engineering Materials》2018,20(2)
74.
Romain Carron Enrico Avancini Thomas Feurer Benjamin Bissig Paolo A. Losio Renato Figi 《Science and Technology of Advanced Materials》2018,19(1):396-410
Cu(In,Ga)Se2-based solar cells have reached efficiencies close to 23%. Further knowledge-driven improvements require accurate determination of the material properties. Here, we present refractive indices for all layers in Cu(In,Ga)Se2 solar cells with high efficiency. The optical bandgap of Cu(In,Ga)Se2 does not depend on the Cu content in the explored composition range, while the absorption coefficient value is primarily determined by the Cu content. An expression for the absorption spectrum is proposed, with Ga and Cu compositions as parameters. This set of parameters allows accurate device simulations to understand remaining absorption and carrier collection losses and develop strategies to improve performances. 相似文献
75.
Jinlong Du Zaoming Wu Yanxiang Liang Xingjun Wang Peipei Wang 《Science and Technology of Advanced Materials》2018,19(1):212-220
The mechanism of radiation-induced detwinning is different from that of deformation detwinning as the former is dominated by supersaturated radiation-induced defects while the latter is usually triggered by global stress. In situ Kr ion irradiation was performed to study the detwinning mechanism of nanotwinned Cu films with various twin thicknesses. Two types of incoherent twin boundaries (ITBs), so-called fixed ITBs and free ITBs, are characterized based on their structural features, and the difference in their migration behavior is investigated. It is observed that detwinning during radiation is attributed to the frequent migration of free ITBs, while the migration of fixed ITBs is absent. Statistics shows that the migration distance of free ITBs is thickness and dose dependent. Potential migration mechanisms are discussed. 相似文献
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Florie VidbergAuthor Vitae Rabah ZeggariAuthor Vitae Christian PieralliAuthor Vitae Clotilde Amiot Christophe RouxAuthor Vitae Bruno WacogneAuthor Vitae 《Sensors and actuators. B, Chemical》2011,157(1):19-25
We present a simple optical micro-system used to measure the transmission spectra of oocytes in order to qualify their maturation stage. Two applications of the device are possible: (i) the evaluation of the maturation stages of oocytes, and (ii) the development of a fertilization indicator. For the first application, GV, MI and MII oocytes were also analysed. Transmission spectra allow the 3 maturation stages to be identified but cannot be used to estimate the maturity of an unknown oocyte. Oocytes are subject to continuous development. This is why spectral separation of the 3 maturation stages cannot be made although they can be visually identified. However, the visual observation remains biologist-dependent. We therefore investigated the temporal maturation evolution of the oocytes in terms of transmission spectra and probability analysis. Results show that oocytes to be fertilized should not only be chosen in the MII stage, but also at the right time during the MII stage. This particular aspect requires further investigation. However, spectral measurements could be used as a technique for monitoring the maturation evolution of the oocytes. Fertilized oocytes exhibiting fertilization abnormalities were also tested. The device proved to be an efficient fertilization indicator. 相似文献
79.
Pi-Guey SuAuthor Vitae Chuen-Chi ShiuAuthor Vitae 《Sensors and actuators. B, Chemical》2011,157(1):275-281
A novel flexible H2 gas sensor was fabricated by the layer-by-layer (LBL) self-assembly of a polypyrrole (PPy) thin film on a polyester (PET) substrate. A Pt-based complex was self-assembled in situ on the as-prepared PPy thin film, which was reduced to form a Pt-PPy thin film. Microstructural observations revealed that Pt nanoparticles formed on the surface of the PPy film. The sensitivity of the PPy thin film was improved by the Pt nanoparticles, providing catalytically active sites for H2 gas molecules. The interfering gas NH3 affected the limit of detection (LOD) of a targeted H2 gas in a real-world binary gas mixture. A plausible H2 gas sensing mechanism involves catalytic effects of Pt particles and the formation of charge carriers in the PPy thin film. The flexible H2 gas sensor exhibited a strong sensitivity that was greater than that of sensors that were made of Pd-MWCNTs at room temperature. 相似文献
80.
Edzer Pebesma Dan CornfordGregoire Dubois Gerard B.M. HeuvelinkDionisis Hristopulos Jürgen PilzUlrich Stöhlker Gary MorinJon O. Skøien 《Computers & Geosciences》2011,37(3):343-352
INTAMAP is a Web Processing Service for the automatic spatial interpolation of measured point data. Requirements were (i) using open standards for spatial data such as developed in the context of the Open Geospatial Consortium (OGC), (ii) using a suitable environment for statistical modelling and computation, and (iii) producing an integrated, open source solution. The system couples an open-source Web Processing Service (developed by 52°North), accepting data in the form of standardised XML documents (conforming to the OGC Observations and Measurements standard) with a computing back-end realised in the R statistical environment. The probability distribution of interpolation errors is encoded with UncertML, a markup language designed to encode uncertain data. Automatic interpolation needs to be useful for a wide range of applications and the algorithms have been designed to cope with anisotropy, extreme values, and data with known error distributions. Besides a fully automatic mode, the system can be used with different levels of user control over the interpolation process. 相似文献