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1.
The visible light driven Bi2MoO6 photocatalyst doped with different contents of Ag nanoparticles was successfully synthesized by a combination of hydrothermal and sonochemical methods. The as-synthesized samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning and transmission electron microscopy (SEM and TEM) and UV–visible spectroscopy to investigate crystalline structure, morphology, composition and photocatalytic properties. XRD patterns and TEM images of the samples revealed pure phase orthorhombic Bi2MoO6 nanoplates without any detection of Ag dopant due to its low concentration and very tiny particle size. TEM images showed that Ag nanoparticles with the size of 10–15 nm were dispersed randomly on the surface of Bi2MoO6. The XPS analysis of Ag/Bi2MoO6 nanocomposites revealed the presence of additional metallic Ag. Photocatalytic activities of the Ag/Bi2MoO6 nanocomposites were evaluated by determining the degradation of rhodamine B (RhB) under visible light radiation. In this research, the 10 wt% Ag/Bi2MoO6 nanocomposites showed the best photocatalytic activity. The results suggest that the dispersion of Ag nanoparticles on the surface of Bi2MoO6 significantly enhances its photocatalytic activity.  相似文献   
2.
In the fields of 3D cadastre and 3D property management system, numerous building property objects are adjacent as primary property units assemble into a 3D coherent set. During visualization process of the coherent set, occlusion, obscure, mazy spatial relationships and relative location relationships among the units of the coherent set cause difficulty in observing and understanding the set and its units. Common 3D objects viewing method, such as rotation and navigation obtaining desired visualization effects through adjusting the view angle and position of the camera's field of view, provides weak interactive experience and orientation control for the coherent set because of the neighbour relationships of the 3D objects inside the set. In this paper, a novel method is proposed to solve the prior problems with two basic distortion methods based on “focus + context” theory. The coherent set is first discretized into individual objects and changed them locations according to linear or orthogonal function, while keeping their relative location and dual topological relationships. To maintain both global context awareness (topology and locations) of 3D coherent set and highlight effect of the focus 3D building property object, three evaluation indexes are adopted to assess the corresponding distortion results. A case study based on the real clustered 3D property in Shenzhen was conducted to evaluate the performance of distortion functions, the result shows that the method proposed in this article can not only expand the visual area of focused object and create a clear line of sight (LOS) to the focal object previously obscured, but also maintain verticality and proximity in some degree to facilitate understand the spatial occupation and distribution of whole coherent objects.  相似文献   
3.
Long-range electronic interaction between Bismuth (Bi) adatoms on graphene formed on a 4H-SiC (0 0 0 1) substrate are clearly observed at room temperature (T = 300 K). Using scanning tunneling microscopy (STM) and density functional theory (DFT) calculations, we have demonstrated that such oscillatory interaction results mainly from the mediation of graphene Dirac-like electrons and the effect of the corrugated surface of SiC substrate. These two factors cause the observed oscillatory interaction with characteristic distribution distances and linear arrangements of Bi adatoms. The present study sheds light on understanding and controlling the nucleation of adatoms and subsequent growth of nanostructures on graphene surface.  相似文献   
4.
The objective of this work was to comparatively evaluate the production of biohydrogen (bio-H2) from tequila vinasses at optimized mesophilic and thermophilic conditions and to elucidate the main metabolic routes involved. Optimal temperatures of 35 °C and 55 °C, and pH of 5.5 maximized the bio-H2 production rates, 25.5 ± 0.01 NmL h−1 and 169.9 ± 8.9 NmL h−1 in the mesophilic and thermophilic regimens, respectively. During the operation of anaerobic sequencing batch reactors, the thermophilic process allowed a volumetric bio-H2 production rate of 519 ± 13 NmL-H2 L−1 d−1 equivalent to 750 ± 19 NmL-H2 Lvinasse−1, while the mesophilic one 448 ± 23 NmL-H2 L−1 d−1 and 647 ± 33 NmL-H2 Lvinasse−1, respectively. Furthermore, the gas produced under thermophilic conditions showed high hydrogen content (86.5%). Finally, formate degradation and glucose fermentation to acetic and butyric acids were the main metabolic routes involved in bio-H2 production under thermophilic conditions, while at mesophilic conditions, the lactate and formate degradation pathways governed.  相似文献   
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从人员质量意识、产品设计质量、原材料/元器件的控制、人员操作质量、产品评审力度等方面,分析质量管理工作中存在的难点,并提出相应的解决措施.  相似文献   
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国内隧道施工技术向“长、大、深”趋势发展,伴随而来的是开挖中遇到各类复杂不良地质,如何既保证施工安全又保证开挖质量,是隧道施工穿越不良地质研究改进的重点。文章结合浩吉铁路王家湾隧道细砂层段落开挖施工,运用水平旋喷技术对软弱不良地层进行加固,形成壳状止水固结体,提高了围岩稳定性,有效解决了隧道开挖过程中涌砂、涌水等问题,保证了施工安全,为类似不良地质隧道施工提供了借鉴经验,具有明显的经济效益和一定的推广价值。  相似文献   
9.
针对装配式空心板桥的防水粘结层的力学性能进行了研究,同时评价了HUT-1桥面防水涂料、SBS改性沥青和乳化沥青三种防水粘结材料的粘结性能,其测试结果是在-25℃条件下HUT-1桥面防水涂料在1.4kg/m2用量下抗剪强度达到最大值,SBS改性沥青和乳化沥青都是在1.2kg/m2用量下抗剪强度达到最大值,25℃条件下不同涂抹量的抗剪强度试验变化趋势与-25℃条件下不同涂抹量的抗剪强度试验变化趋势相近,说明自然环境温度对粘结层力学性能的影响不大.  相似文献   
10.
Aspect-Oriented Software Development promotes the separation of those concerns that cut across several components and/or are tangled with the base functionality of a component, through all phases of the software lifecycle. The benefit of identifying these crosscutting concerns (aspects) at the architectural level in particular is to improve the architecture design and its subsequent evolution, before moving onto detailed design and implementation. However, software architects are not usually experts on using specific AO architecture notations. Therefore, the aim of this paper is to provide support to define and specify aspect-oriented (AO) architectures using non-AO ones as the source. We will use the Model-Driven Development approach to transform a component-based architecture model into an AO architecture model. The CAM (component and aspect model) model and the DAOP–ADL language are the proposals used for modelling and specifying AO architectures. We will show how we automated part of the process and the tool support.  相似文献   
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