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1.
《International Journal of Hydrogen Energy》2020,45(20):11502-11511
Perovskite type materials have high potential photocatalytic application towards both hydrogen energy generation and organic dye degradation due to their high stability and good reusability. Here, it is the first analysis of photocatalytic degradation of RhB and hydrogen energy evolution under visible light over MoS2/LaFeO3 nanocomposite. The physicochemical properties of the materials were characterized using a range of techniques such as XRD, TEM, XPS, FTIR, PL, photocurrent, etc. The optical properties of the nanocomposite show good absorption in UV-Vis spectra as compared to the bare LaFeO3. In this study, MoS2/LaFeO3 nanocomposite was synthesized through single step in situ hydrothermal processes with a narrow bandgap, enhanced photocatalytic application under visible light. This novel MoS2/LaFeO3 nanocomposite is an efficient and promising photocatalyst for both hydrogen energy evolution and organic dye degradation. 相似文献
2.
《Carbon》2015
Three-dimensional (3D) highly interconnected graphitized macroporous carbon foam with uniform mesopore walls has been successfully fabricated by a simple and efficient hydrothermal approach using resorcinol and formaldehyde as carbon precursors. The commercially available cheap polyurethane (PU) foam and Pluronic F127 were used as a sacrificial polymer and mesoporous structure-directing templates, respectively. The graphitic structure of carbon foam was obtained by catalytic graphitization method using iron as catalyst. Three different carbon foams such as graphitized macro-mesoporous carbon (GMMC) foam, amorphous macro-mesoporous carbon (AMMC) foam and graphitized macroporous carbon (GMC) foam were fabricated and their physicochemical and mechanical properties were systematically measured and compared. It was found that GMMC possess well interconnected macroporous structure with uniform mesopores located in the macroporous skeletal walls of continuous framework. Besides, GMMC foam possesses a well-defined graphitic framework with high surface area (445 m2/g), high pore volume (0.35 cm3/g), uniform mesopores (3.87 nm), high open porosity (90%), low density (0.30 g/cm3) with good mechanical strength (1.25 MPa) and high electrical conductivity (11 S/cm) which makes it a promising material for many potential applications. 相似文献
3.
CFTR氯离子通道是目前国际上新兴的治疗分泌型腹泻的分子药靶,CFTR抑制剂通过阻断离子通道的过度分泌来治疗腹泻症状。由于其抑制剂极为稀少,因此CFTR抑制剂的筛选工作是相关领域中最基础、最关键的环节。天然产物兼具结构和生物活性的多样性,在新药和先导化合物的发现中起着重要作用,是药物开发的主要来源,而食品药品来源的天然产物更因为对人体安全无毒副作用而倍受青睐。食品药品来源的CFTR氯离子通道抑制剂对于CFTR相关的腹泻等疾病的机理研究和治疗具有重要价值,同时也为天然产物资源用于现代药物发现提供了依据。 相似文献
4.
Object detection on 360°images is a vital component of 3D environment perception. The existing methods either treat panoramic images (usually represented in equirectangular projection—ERP) as normal FoV images and endure the distortions or project them into the less-distortion format and narrow the FoV, leading to unsatisfactory performance in practical applications. To solve this problem, we propose a dual-projection 360°object detection network named Bip R-CNN, consisting of three modules: a bi-projection feature extractor, a cross-projection region-of-interest (RoI) searcher, and a classification and regression predictor. Specifically, we extract the equirectangular and corresponding dual-cubemap features simultaneously from the input images. Besides, Projection-Inter Feature Fusion and Projection-Intra Feature Fusion are designed to allow the mutual interaction between the bi-projective features and promote the integration of features at different scales, respectively. In the proposed cross-projection RoI Searcher, we search for the bounding box (BBox) locations on cubemap from the corresponding ERP spherical proposals, bridging the RoIs of two different projection formats at feature level. Finally, the cube proposals are used to detect objects in the last predictor module. Considering the scarceness of the existing panoramic dataset (only indoor scenes), we propose an efficient approach to convert conventional datasets into annotated panoramic datasets without manual intervention, increasing the diversity of panoramic datasets. Extensive experiments are conducted on the synthetic and real-world datasets with spherical criteria, demonstrating our superiority to other state-of-the-art solutions. 相似文献
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6.
为了制定企业可持续发展的战略决策,基于SWOT矩阵,创建了企业竞争力与可持续发展度战略决策图.它以反映企业竞争实力阶段性水平的企业竞争力平均因子得分为横坐标;以反映企业竞争实力变化规律的企业可持续发展度为纵坐标.该图把企业竞争实力的强度和可持续发展的变化趋势进行了有机结合. 相似文献
7.
The Chan–Vese (C–V) model is an ineffective method for processing images in which the intensity is inhomogeneous. This is especially true for multi-object segmentation, in which the target may be missed or excessively segmented. In addition, for images with rich texture information, the processing speed of the C–V is slow. To overcome these problems, this paper proposes an effective multi-object C–V segmentation model based on region division and gradient guide. First, a rapid initial contour search is conducted using Otsu’s method. This contour line becomes the initial contour for our multi-object segmentation C–V model based on a gradient guide. To achieve the multi-object segmentation the image is then converted to a single level set whose evolution is controlled using an adaptive gradient. The feasibility of the proposed model is analyzed theoretically, and a number of simulation experiments are conducted to validate its effectiveness. 相似文献
8.
Hans van der Heijden 《Expert systems with applications》2012,39(10):8573-8583
This study concerns itself with providing user support for a decision problem in logistic regression analysis: given a set of metric variables and one binary dependent variable, select the optimal subset of variables that can best predict this dependent variable. The problem requires an evaluation of competing models based on heuristic selection criteria such as goodness-of-fit and prediction accuracy. This paper documents the heuristics, formalizes the algorithms, and eventually presents an interactive decision support system to facilitate the selection of such an optimal model.This study adds to the sparsely studied domain of expert systems for social science researchers, and makes three contributions to the literature. First, the study formalizes a number of heuristics to arrive at optimal logistic regression models. Second, the study presents two computational algorithms that incorporate these formalized heuristics. Third, the paper documents an implementation of these algorithms through an interactive decision support system. The study concludes with a discussion on the risks of relying too heavily on the system and with future opportunities for research. 相似文献
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10.
针对任务可拆分的资源受限的项目调度问题,提出了一种人工蜂群算法与任务可拆分的串行调度机制相结合的优化方法.人工蜂群算法中每个食物源的位置代表一组项目任务的优先权序列,优先权序列通过调度生成机制转换为可行调度方案,迭代中由三种人工蜂执行不同的操作来实现全局最优解的更新.实算表明,基于优先权的人工蜂群算法可以有效求解任务可拆分项目调度问题,收敛速度较快且精度较高. 相似文献