- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Data Augmentation Method of SAR Image Dataset
摘要: Large-scale high-quality, standardized, measurable and accurate data is the key to promote the progress of the algorithm in the radar remote sensing. Data scaling is a widespread technology that increases the size of a labeled training set dataset through specific data transformations. Synthetic Aperture Radar (SAR) image simulators based on computer-aided mapping models play an important role in SAR applications such as automatic target recognition and image interpretation, but the accuracy of this simulator is due to geometric errors and simplification of electromagnetic calculations. In order to achieve a SAR image datasets with the known target and azimuth angles, we can generate the desired image directly from a known image database. We can realize the augmentation of SAR image data set through linear synthesis and Generative Adversarial Networks, which can generate SAR images for the specified azimuth.
关键词: generative adversarial networks,SAR image,linear synthesis
更新于2025-09-23 15:21:21
-
PATTERN SYNTHESIS FOR LARGE PLANAR ANTENNA ARRAYS USING A MODIFIED ALTERNATING PROJECTION METHOD
摘要: A pattern synthesis approach based on a modi?ed alternating projection method for large planar arrays is presented in this paper. In the alternating projection method, pattern synthesis problem is considered as ?nding the intersection between two sets: the speci?cation set and the feasible set. The former contains all the patterns that want to be obtained, while the latter contains all the patterns that can be realized. An element belongs to both sets is a solution to the problem. In this paper, a modi?ed projection operator which varies with the iteration number is introduced because the conventional alternating projection method is known to su?er from low convergence rate and/or trapping on local optimum depending on the starting point. When the planar array has a nonuniform element layout, the unequally spaced elements are interpolated into virtual uniform elements with an interpolation of the least square sense. Then the synthesis problem is converted to the problem of a uniform array. Finally, several examples are presented to validate the advantages of the proposed method. Results show that the modi?ed method is fast and obtains better results than the conventional one.
关键词: modi?ed alternating projection method,interpolation,planar antenna arrays,nonuniform element layout,pattern synthesis
更新于2025-09-23 15:21:21
-
Graphene Oxide - Applications and Opportunities || Graphene Oxide/Reduced Graphene Oxide Aerogels
摘要: In this chapter, we will discuss aerogels based on graphene oxide/reduced graphene oxide—promising composite materials, based on 2D carbon nanoparticles, with a certain architecture that prevents aggregation of graphene layers with a highly developed surface that have a high potential technological realization as materials for supercapacitors, sensors, batteries, and actuators. This chapter describes the existing methods for producing composite aerogels based on graphene oxide/reduced graphene oxide, the structural features of these materials, the most relevant studies in the areas of surface modification, architectural control, improvement of mechanical properties, and the most interesting applications. It has been shown that such materials have relatively high specific surface values and a high degree of exfoliation of graphene layers, but an urgent need is to improve them, which is due to the fragility of graphene aerogels and composite materials based on them, as well as the need to modify the surface to control porosity.
关键词: cross linking,hydrothermal synthesis,highly porous materials,carbon based materials,reduced graphene oxide aerogels,graphene oxide aerogels,self-gelation
更新于2025-09-23 15:21:21
-
RECENT APPLICATIONS IN ORGANIC SYNTHESIS OF VISIBLE LIGHT PHOTOREDOX CATALYSIS
摘要: RECENT APPLICATIONS IN ORGANIC SYNTHESIS OF VISIBLE LIGHT PHOTOREDOX CATALYSIS. In the past few years, photoredox catalysis has become a powerful tool in the field of organic synthesis. Using this efficient method, it is possible to excite organic compounds from visible light and attain alternative mechanistic pathways for the formation of chemical bonds, a result which is not obtainable by classical methods. The rapid growth of work in the area of photoredox catalysis is due to its low cost, broad chemical utility protocols, and, especially, its relevancy from the green and sustainable chemistry viewpoints. Thus, this study proposes a brief theoretical discussion of and highlights recent advances in visible-light-induced photoredox catalysis through the analysis of catalytic cycles and intermediates.
关键词: visible light,photoredox catalysis,organocatalysis,organic synthesis,transition metals
更新于2025-09-23 15:21:21
-
[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Experimental Verification of One-Dimensional Mirrored Aperture Synthesis
摘要: Mirrored aperture synthesis (MAS) has been proposed to utilize a few antennas to provide high spatial resolution for atmospheric remote sensing. In order to verify the fundamentals of mirrored aperture synthesis (MAS) further, a prototype working at V band was developed in the past two years. In this paper, the prototype is briefly introduced, and then some indoor experiments and the experimental results for one-dimensional MAS based on the prototype are presented, mainly including the fringe pattern experiment for verifying the correlation output and the imaging experiment based on two point sources for evaluating the spatial resolution of MAS.
关键词: fringe pattern,spatial resolution,Mirrored aperture synthesis
更新于2025-09-23 15:21:21
-
Preparation of ordered mesoporous Au using double gyroid mesoporous silica KIT-6 via a seed-mediated growth process
摘要: Ordered mesoporous Au was prepared using double-gyroid (cubic Ia3d) mesoporous silica KIT-6 as a template. The Au frameworks were formed within the template via a seed-mediated growth process. Au nanoparticles were initially prepared as seeds within the mesopores, and subsequently, they were grown under mild and controlled reducing conditions. The transmission electron micrographs and scanning electron micrographs of mesoporous Au after the removal of the template revealed the formation of mesoporous Au replicas. The small-angle X-ray scattering pattern of mesoporous Au reveals that the obtained mesoporous Au has a cubic I4132 mesostructure, which is different from that of the original template, implying that Au was deposited within only one mesochannel of the two interconnected ones. The seed-mediated growth process is a key factor in the successful formation of ordered mesoporous Au using a mesoporous silica template. Our preparative method can serve as a guide for further development of synthetic and materials chemistry of mesoporous Au.
关键词: Gold,Nanostructure,Template synthesis,Mesoporous materials
更新于2025-09-23 15:21:21
-
Time Dependent Facile Hydrothermal Synthesis of TiO2 Nanorods and their Photoelectrochemical Applications
摘要: In the present investigation, we report facile hydrothermal synthesis of TiO2 nanorods with high density rutile phase on Transparent Conducting Oxide (TCO) for enhanced solar cell application. The structural, optical, morphological, compositional and electrochemical properties are investigated by detailed XRD, UV-Vis-NIR spectrophotometer, FESEM, TEM, EDAX, XPS and photoelectrochemical studies. It is demonstrated that, the deposited TiO2 thin film shows pure rutile phase with tetragonal crystal structure. Optical spectra showed strong light absorption in UV region and FESEM images confirm the time dependent growth of TiO2 nanorods. EDAX and XPS Spectra confirm the formation of pure TiO2 nanorods. Photoelectrochemical performance with respect to time dependent growth of TiO2 nanorods showed highest photoconversion efficiency = 5.1%.
关键词: Hydrothermal synthesis,Photoelectrochemical cell property,Single crystalline,Photoconversion efficiency,TiO2 nanorods,Transparent conducting oxide (TCO)
更新于2025-09-23 15:21:21
-
Structural, optical and photocatlytic properties of zinc oxide nanoparticles obtained by simple plant extract mediated synthesis
摘要: We report a facile and inexpensive method to prepare zinc oxide nanoparticles with different particle size and shape using Achyranthes aspera and Couroupita guianensis leaf extracts as the reducing agent and zinc nitrate as a precursor. The prepared zinc oxide nanoparticles were analyzed by various characterization methods and obtained results evidently revealed that crystalline parameter, purity, optical absorption, band gap, particle size and shape of the ZnO nanoparticles significantly influenced by the type of leaf extract used as reducing agent. Further, photocatlytic activity study obviously demonstrates that prepared samples exhibits superior photocatlytic activity for the degradation of methylene blue dye by creating superoxide anion radicals and OH radicals under photonic irradiation. Hence, prepared zinc oxide nanoparticles by plant extract mediated synthesis can be applied as a photocatlyst for the possible waste water treatment in textile industry.
关键词: Waste water treatment,Photocatalytic activity,Plant extract mediated synthesis,Methylene blue dye,Zinc oxide nanoparticles
更新于2025-09-23 15:21:21
-
Green Synthesis and Electrical Properties of p-CuO/n-ZnO Heterojunction Diodes
摘要: Green production of nanomaterials and their materials properties studies are majorly important for the futuristic development of nanodevices. We had green synthesized the ZnO and CuO nanoparticles using the extract of “Eucalyptus globulus” leaves. The obtained ZnO and CuO nanoparticles were studied for their structural, morphological and optical properties. The green synthesized CuO and ZnO nanoparticles have showed the crystalline size of about 12.29 and 10.16 nm. The transmission electron microscopic images of green synthesized ZnO and CuO nanoparticles revealed the morphological information and their respective average sizes of 46 and 32 nm. Optical absorbance spectrum revealed the existence of morphology based quantum confinement in the green ZnO and CuO nanoparticles. Further we have fabricated the p-CuO/n-ZnO heterojunction device using the green synthesized nanoparticles and also evaluated the electrical properties of the p–n junction diode. Under the light illumination the photodiode characteristic were studied for the obtained p–n junction diode. Finally, the energy band diagram of the photodiode responsible for the electronic transport had also discussed.
关键词: Electrical properties,p–n Heterojunction,Green synthesis,Photodiode
更新于2025-09-23 15:21:21
-
Preparation of Highly Efficient CoFe2O4/Zn2SnO4 Composite Photocatalyst for the Degradation of Rhodamine B Dye from Aqueous Solution
摘要: CoFe2O4/Zn2SnO4 composite was synthesized using a simple two-step process and applied as a novel-efficient photocatalyst for the rhodamine B degradation from aqueous solution. Characterization techniques such as X-ray diffraction (XRD), N2 adsorption-desorption isotherms, scanning electron microscopy (SEM), EDS analysis, and diffuse reflectance spectroscopy were employed in order to investigate the physical and chemical properties of composite. Higher values of the specific surface area, pore volume and diameter, and a smaller band-gap energy promoted a greater catalytic activity of CoFe2O4/Zn2SnO4 composite when compared to Zn2SnO4. A rapid decolorization of dye solution was observed at 40 min of reaction using the CoFe2O4/Zn2SnO4 catalyst, being 2.5 times faster than the Zn2SnO4 alone. Therefore, the CoFe2O4/Zn2SnO4 composite shows extraordinarily high photocatalytic activity toward the degradation of rhodamine B dye from aqueous solution.
关键词: Coupled oxides,Photocatalysis,Rhodamine B,Synthesis,CoFe2O4/Zn2SnO4
更新于2025-09-23 15:21:21