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Short-Period Multilayer X-ray Mirrors for “Water” and “Carbon Windows” Wavelengths
摘要： This review paper summarizes and provides an overview of our recent studies related to two types of short-period multilayer X-ray mirrors, W/B4C and Co/C. It deals with the experimental observation of the layer intermixing effects and how they affect the X-ray mirror's optical performance. The paper presents also some examples of using the fabricated X-ray mirrors in focusing and imaging experiments at the working wavelengths 2.48 nm and 4.47 nm.
关键词： Thin Films,Interlayer Interaction,Metal-Carbon Compositions,Short-Period Multilayer Structures,X-ray Multilayer Mirrors,X-ray Optics
更新于2025-09-23 15:23:52
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Assembly of shell/core CDs@CaF2 nanocomposites to endow polymer with multifunctional properties
摘要： Assembly of shell/core CDs@CaF2 nanocomposites to endow polymer with multifunctional properties. The shell/core structure of CDs@CaF2 nanocomposites (CCNCs) were prepared by assembling fluorescent carbon dots (CDs) inside the inorganic CaF2 substrates using co-precipitation interaction. CDs endow the CaF2 with the properties of good UV-absorbing behavior and efficient blue light emission instead of rare earth such as Eu that is expensive and susceptible to polluting environment during the mining process. Due to nanometer size and surface effect of nano CaF2, and approximate refractive index between CaF2 and polyethylene (PE), CCNCs/PE film exhibits better elongation at break than pure PE film while maintaining high transparency and visible light transmittance. Simultaneously, the CCNCs/PE film was experimentally demonstrated to have outstanding performance of anti-UV and blue light conversion, which decide that CCNCs can be a novel and promising multifunctional additive applied in polymers especially for greenhouse film.
关键词： CaF2,Carbon dots,Polymer,Light conversion,Anti-UV,Nano-toughening
更新于2025-09-23 15:23:52
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[SpringerBriefs in Energy] Grid Parity and Carbon Footprint (An Analysis for Residential Solar Energy in the Mediterranean Area) ||
摘要： In the context of global warming, big cities’ atmosphere is always more contaminated and natural disasters in augmentation, solar energy, and more generally renewable energies are sources of great enthusiasm. Besides, thanks to recent improvements in technologies, the costs of photovoltaic (PV) have strongly declined in the last decades and are now accessible for particulars. The purpose of this project is then to study the economic profitability of solar energy for a residential use. A common and appropriate tool for this is the grid parity. This term, largely used in the literature, refers to the moment when producing electricity from solar modules will have the same cost than buying it from the grid. Grid parity depends mainly on the geographic position (as solar irradiation is very different from a place to another) and on the local electricity price. Consequently, a country with expensive electricity and a high rate of irradiation is more likely to reach grid parity soon. In the present study, the geographic framework chosen is the Mediterranean area, which includes countries with similar climates but with other differences sufficiently important to obtain interesting comparative results. The PV system used in the following model is a basic one since it does not include energy storage or resale to the grid, which gives a conservative perspective to the study. Extensive financial analysis is conducted in order to determine under which conditions it is the most profitable. The secondary objective is to evaluate the environmental impact of solar energy, mainly by carrying out carbon footprint analysis. It basically consists in comparing the emissions released by the manufacturing process of the modules to the reduction obtained thanks to its utilization. This study is first realized at an individual level and, then, is generalized at a national one in order to measure what could be the contribution of a massive investment in residential solar energy to the Paris agreement objectives.
关键词： Mediterranean area,Carbon footprint,Residential solar energy,Economic profitability,Environmental impact,Photovoltaic energy,Grid parity
更新于2025-09-23 15:23:52
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Synthesis of Carbon Nanodots from Cellulose Nanocrystals Oil Palm Empty Fruit by Pyrolysis Method
摘要： Biomass such as cellulose is one of the most common abundant organic materials on the Earth. Biomass has carbon chain that could be an excellent choice for the fabrication of carbon materials. Cellulose nanocrystal is nano-sized cellulose and could become the potential source in fabricating carbon nanodots that are affected by pyrolysis temperature. In fact, the size and temperature are essentially important to synthesize the carbon nanodots. This research is contributed to synthesize this material, and to investigate the effect of temperature. The percentage of cellulose nanocrystals and carbon nanodots obtained are less than 50%. Carbon nanodots are synthesized by pyrolysis method and cellulose nanocrystals are fabricated by membrane method. TEM analysis shows that cellulose nanocrystals are nano-sized. Under UV light source, the samples show fluoroscencing colours i.e. blue to green. From this research it can be concluded that the temperature affects the characteristics of carbon nanodots produced by pyrolysis method.
关键词： Pyrolysis,Cellulose Nanocrystals,Fluorescent,Carbon Nanodots
更新于2025-09-23 15:23:52
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Electric field assisted ion adsorption with nanoporous SWCNT electrodes
摘要： The permeable single wall carbon nanotube (SWCNT) film electrodes of high electrical conductivity for filtration of ions are promising for future water treatment technology. The permeable SWCNT film electrodes were obtained by the use of the Zn/Al-based dispersant-aided SWCNT ink. The G band peak position and ID/IG value of Raman spectra do not change before and after the polarization of the SWCNT electrodes, showing the robustness of permeable SWCNT film electrodes. The analysis of N2 adsorption isotherms showed that microporosity and specific surface area of the SWCNT electrodes were larger than those of the pristine SWCNT, due to the debundling of SWCNTs and removal of the caps of SWCNT on the dispersion treatment. Application of the electric voltage above ?3 V to the SWCNT electrodes enhanced markedly the adsorption-mediated permeability of K+ ions, reaching the removability of 90%. The removability dependence of Na+ ions on the initial ion concentration showed that the SWCNT permeation electrodes filter was efficient for diluted Na+ ionic solution. The ions of smaller Stokes radius were adsorbed for the mixed ionic solution of Li+, Na+, K+, Rb+, and Cs+, suggesting that the inner tube space of SWCNT electrodes is important for adsorption of ions.
关键词： Permeable electrodes,Electrosorption,Electric field assistance,Ion adsorption,Water treatment,Single wall carbon nanotube
更新于2025-09-23 15:23:52
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Resonant Enhancement of THz Radiation Through Vertically Aligned Carbon Nanotubes Array by Applying Wiggler Magnetic Field
摘要： The present analysis develops a novel theory of terahertz radiation generation by beating of two laser beams, incident obliquely on the array of vertically aligned carbon nanotubes (CNTs) in the presence of an external wiggler magnetic field. The array of CNTs behaves as nanoantenna to generate THz radiations. The incident lasers exert a ponderomotive force on the electrons of the CNTs to produce nonlinear oscillatory velocity, which beats with the applied wiggler magnetic field. This beating produces a nonlinear current at (ω2 ? ω1, k2 ? k1 + k0) which acts as an antenna to produce the THz radiation. We observe that when the beat frequency (ω2 ? ω1) lies near the effective plasmon frequency of the CNTs, strong THz radiation is produced due to a resonant interaction of the laser with CNT electrons. The externally applied wiggler magnetic field enhances the efficiency of THz radiation of nanoantenna by providing the necessary momentum to the generated THz radiation. We explore the impact of radius and length of nanotubes on the efficiency of THz generation. The generated THz power is enhanced at an optimum angle of incidence of lasers with an array of CNTs.
关键词： THz radiation,Carbon nanotubes,Antenna theory,Wiggler magnetic field,Plasma,Nanotechnology
更新于2025-09-23 15:23:52
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Carbon Nanotube Thin Films for High-Performance Flexible Electronics Applications
摘要： Carbon nanotube thin films have attracted considerable attention because of their potential use in flexible/stretchable electronics applications, such as flexible displays and wearable health monitoring devices. Due to recent progress in the post-purification processes of carbon nanotubes, high-purity semiconducting carbon nanotubes can be obtained for thin-film transistor applications. One of the key challenges for the practical use of carbon nanotube thin-film transistors is the thin-film formation technology, which is required for achieving not only high performance but also uniform device characteristics. In this paper, after describing the fundamental thin-film formation techniques, we review the recent progress of thin-film formation technologies for carbon nanotube-based flexible electronics.
关键词： Flexible electronics,Carbon nanotube,Thin film
更新于2025-09-23 15:23:52
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Self-hybridized coralloid graphitic carbon nitride deriving from deep eutectic solvent as effective visible light photocatalysts
摘要： The room temperature deep eutectic solvent (DES) is demonstrated as an ideal precursor to prepare self-hybridized graphitic carbon nitride (g-C3N4) for the first time, for its special components, randomly reorganized molecules and extensive hydrogen bonds. In this work, by adjusting the proportion of urea and ammonium thiocyanate in the precursor DES, the self-hybridized coralloid g-C3N4, stacked by a mass of double-layer g-C3N4/g-C3N4 nanocages, were prepared without any templates. Compared to conventional g-C3N4 prepared using melamine, urea and AT as precursors, the improved charge transfer between the interfaces of the self-hybridized g-C3N4 has been demonstrated, which is attributed to the well-matched electronic band structures of the two g-C3N4 species, the abundant 2D/2D interfacial contact and increased photocatalytic active sites. As expected, it exhibits highly enhanced photocatalytic activity, which is among the best g-C3N4 photocatalysts without doping any other elements.
关键词： G-C3N4/g-C3N4 heterojunction,Graphitic carbon nitride,Photocatalysis,Nanocages,Deep eutectic solvents
更新于2025-09-23 15:23:52
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[IEEE 2018 IEEE International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO) - Hangzhou, China (2018.8.13-2018.8.17)] 2018 IEEE International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO) - Bottom up Nano-integration Technique for the Fabrication of Novel Superconducting Quantum Interference Devices Based on Granular Superconducting Diamond
摘要： The report is focused on the fabrication and characterization of nano-necklaces created from individual nanostructures namely heavily boron-doped superconducting nano-diamond grains and BIISCO whiskers. The production of nanostructures from individual nano-diamonds is done using 3D mechanical nano-manipulation and nano-assembling based on new generation shape memory alloy composite nanotweezers. Quantum transport of such nano-necklaces will be probed in order to study the confinement effects on superconductivity and other related quantum effects. This bottom-up nano-integration technique thus demonstrates a niche fabrication route for the realization of novel complex nanostructured quantum rings which may be of use for quantum information technologies.
关键词： nanodiamonds,bottom-up paradigm,carbon based nanomaterials,nanogripper,shape memory effect,nano-manipulation,superconductivity
更新于2025-09-23 15:23:52
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One pot green synthesis of C-dots from groundnuts and its application as Cr(VI) sensor and in vitro bioimaging agent
摘要： The emergence of ?uorescent carbon dots (C-dots) has received special attention due to their distinct characteristics which are advantageous for optical sensing and bioimaging applications. Cr(VI) is considered a hazardous environmental pollutant hence requires a simple and e?ective method for its detection and recovery. Herein, we have synthesized both C-dots and N-doped C-dots from ground nuts employing a cost-e?ective and green hydrothermal method. N-C-dots exhibits a remarkably enhanced quantum yield (17.6%) as compared to undoped C-dots (7.8%). In addition,the N-C-dots showed amazing selectivity towards Cr(VI) in the metal sensing application. Cr (VI) induced quenching of ?uorescence was recovered using Humic acid as well as Glutathione thus exhibiting an o?-on type sensing mechanism. The limit of detection (LOD) for Cr(VI) using N-C-dots was found to be 0.1 mg/L. C-dots possess comparatively low cytotoxicity than N-C-dots at higher concentration thereby making them an e?cient candidate for bioimaging of MCF-7 cells.
关键词： Bioimaging,Carbon dots(C-dots),Cr(VI) sensing,Groundnut,Glutathione,Humic acid
更新于2025-09-23 15:23:52