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1.
基于深度学习的图像超分辨率算法通常采用递归的方式或参数共享的策略来减少网络参数,这将增加网络的深度,使得运行网络花费大量的时间,从而很难将模型部署到现实生活中。为了解决上述问题,本文设计一种轻量级超分辨率网络,对中间特征的关联性及重要性进行学习,且在重建部分结合高分辨率图像的特征信息。首先,引入层间注意力模块,通过考虑层与层之间的相关性,自适应地分配重要层次特征的权重。其次,使用增强重建模块提取高分辨率图像中更精细的特征信息,以此得到更加清晰的重建图片。通过大量的对比实验表明,本文设计的网络与其他轻量级模型相比,有更小的网络参数量,并且在重建精度和视觉效果上都有一定的提升。 相似文献
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Among various carbon materials, diamond stands out due to excellent physical and chemical properties. In this work, we designed Dia@SiO2@Ag composites combining diamond micropowder and Ag nanoparticles by a simple chemical method and obtained stable substrate for surface enhanced Raman scattering (SERS) owing to its high surface-to-volume ratio, low density, as well as close bond between diamond and Ag. As-prepared Dia@SiO2@Ag presented high activity to detect crystal violet and rhodamine 6G molecules, which was demonstrated by significantly enhanced SERS spectra and high enhancement factor values (108-109). Moreover, Dia@SiO2@Ag also showed desired sensitivity, which was investigated by detection limit. Therefore, our study provided more theoretical support and broadened the functional applications of diamond, particularly in Raman detection. 相似文献
3.
建立并优化一种基于高效薄层色谱和表面增强拉曼联用检测技术的方法,用于快速准确定性定量检测葡萄汁中的苏丹染料掺伪。使用石油醚/丙酮/乙酸(9/1/0.1,体积比)作为流动相在硅胶板上对目标物进行色谱分离,考察纳米银胶体浓度、外加电解质种类、浓度以及入射激光波长等参数对检测信号质量的影响。结果表明,10倍浓缩的纳米银胶体,633nm入射激光,辅以0.5~1.0mol/L NaCl最适合4种目标物的检测。优化检测条件后,检测灵敏度可达0.01~0.05mg/kg;在1~20 mg/kg浓度范围内,检测结果表现出良好的线性关系,R~20.996。不仅如此,对葡萄汁样品的测试中,该方法也表现出良好的准确性(添加回收率72%~104%)和精密度(RSD 4.5%~9.6%),因此特别适于大批量饮料和食品样品中非法色素添加的筛检。 相似文献
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Chemical looping glycerol reforming for hydrogen production by Ni@ZrO2 nanocomposite oxygen carriers
Bo Jiang Lin Li Zhoufeng Bian Ziwei Li Yang Sun Zhehao Sun Dawei Tang Sibudjing Kawi Binlin Dou Maria A. Goula 《International Journal of Hydrogen Energy》2018,43(29):13200-13211
The research describes the synthesis of nanocomposite Ni@ZrO2 oxygen carriers (OCs) and lanthanide doping effect on maintaining the platelet-structure of the nanocomposite OCs. The prepared OCs were tested in chemical looping reforming of glycerol (CLR) process and sorption enhanced chemical looping reforming of glycerol (SE-CLR) process. A series of characterization techniques including N2 adsorption-desorption, X-ray diffraction (XRD), inductively coupled plasma optical emission spectrometry (ICP-OES), high resolution transmission electron microscopy (HRTEM), H2 temperature-programmed reduction (H2-TPR), H2 pulse chemisorption and O2 temperature-programmed desorption (O2-TPD) were used to investigate the physical properties of the fresh and used OCs. The results show that the platelet-stack structure of nanocomposite OCs could significantly improve the metal support interaction (MSI), thus enhancing the sintering resistance. The effect of lanthanide promotion on maintaining this platelet-stack structure increased with the lanthanide radius, namely, La3+ > Ce3+ > Pr3+ > Yb3+. Additionally, the oxygen mobility was also enhanced because of the coordination of oxygen transfer channel size by doping small radius lanthanide ions. The CeNi@ZrO2 showed a moderate ‘dead time’ of 220 s, a high H2 selectivity of 94% and a nearly complete glycerol conversion throughout a 50-cycle CLR test. In a 50-cycle SE-CLR stability test, the CeNi@ZrO2CaO showed high H2 purity of 96.3%, and an average CaCO3 decomposition percentage of 53% without external heating was achieved. 相似文献
6.
Mohammad Hosein Emami Baghdadi Houman Darvish Hosein Zanbouri Karim Rouhibakhsh 《Petroleum Science and Technology》2018,36(11):787-792
Recently the studies expressed that the noticeable number of oil reservoirs in all over the world are heavy oil and bitumen reservoirs. So the importance of enhancement of oil recovery (EOR) processes for heavy oil and bitumen reservoirs is highlighted. The Dilution of the reservoir fluid by solvents such as tetradecane is one of well-known methods for these types of reservoirs which effects oil recovery by decreasing viscosity. In the present study, Fuzzy c-means (FCM) algorithm was coupled with Adaptive neuro-fuzzy inference system (ANFIS) to predict viscosity of bitumen and tetradecane in terms of temperature, pressure and weight percent of tetradecane. The coefficients of determination for training and testing steps were calculated such as 0.9914 and 0.9613. The comparison of results and experimental data expressed that FCM-ANFIS algorithm has great potential for estimation of viscosity of bitumen and tetradecane. 相似文献
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8.
Fluorescence‐Activated Cell Sorters: Standing Surface Acoustic Wave (SSAW)‐Based Fluorescence‐Activated Cell Sorter (Small 40/2018) 下载免费PDF全文
9.
黔北正安地区安场向斜石牛栏组为一套深水陆棚沉积的泥灰岩地层,前期钻探显示,石牛栏组气藏分布与裂缝发育程度密切相关,为典型的裂缝型气藏。为进一步对安场向斜石牛栏组储层的裂缝平面展布规律进行研究,该文通过岩心、成像测井等资料分析目的层的裂缝发育特征,优选裂缝预测敏感地震属性,基于地震像素处理的裂缝增强属性对石牛栏组裂缝分布进行了预测。研究结果表明:利用常规的地震曲率属性预测裂缝识别能力有限,而基于地震像素处理的地震数据能够有效改善小断层及构造形变特征成像,在此基础上开展的裂缝增强属性可大大提高裂缝的识别能力,经实钻井验证,基于叠后地震属性裂缝分布预测方法的结果与钻井泥浆漏失点综合吻合率达83.3%以上,预测结果较为可靠,该研究为石牛栏组区带优选及钻井风险预警提供了技术支撑。 相似文献
10.
Liqiang Ren Shujie Yang Peiran Zhang Zhiguo Qu Zhangming Mao Po‐Hsun Huang Yuchao Chen Mengxi Wu Lin Wang Peng Li Tony Jun Huang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(40)
Microfluidic fluorescence‐activated cell sorters (μFACS) have attracted considerable interest because of their ability to identify and separate cells in inexpensive and biosafe ways. Here a high‐performance μFACS is presented by integrating a standing surface acoustic wave (SSAW)‐based, 3D cell‐focusing unit, an in‐plane fluorescent detection unit, and an SSAW‐based cell‐deflection unit on a single chip. Without using sheath flow or precise flow rate control, the SSAW‐based cell‐focusing technique can focus cells into a single file at a designated position. The tight focusing of cells enables an in‐plane‐integrated optical detection system to accurately distinguish individual cells of interest. In the acoustic‐based cell‐deflection unit, a focused interdigital transducer design is utilized to deflect cells from the focused stream within a minimized area, resulting in a high‐throughput sorting ability. Each unit is experimentally characterized, respectively, and the integrated SSAW‐based FACS is used to sort mammalian cells (HeLa) at different throughputs. A sorting purity of greater than 90% is achieved at a throughput of 2500 events s?1. The SSAW‐based FACS is efficient, fast, biosafe, biocompatible and has a small footprint, making it a competitive alternative to more expensive, bulkier traditional FACS. 相似文献