It is well known the remarkable optical properties of both graphene and left handed materials, for which we study the optical properties of a multilayer system building by graphene-dielectric-left hand material. In this work, we show the transmission, reflection and absorption spectra for a different set of parameters of the left-handed material structure. It is important to highlight that the inclusion of graphene remarkably modifies the transmission and absorption spectra. The optical properties of the graphene-LHM can be modulated via the different parameters of system. We showed that the fill function do not change the line form of the spectra, however, modify their amplitudes. With respect to light polarization, it’s possible to observe that the spectra are widen for TM respect to TE polarization.

Nb-doped TiO2 thin-films were prepared on fluorine-doped tin oxide (FTO) coated glass directly with niobium ethoxide and TiCl4 in water under the acidic conditions with several concentrations of HCl at 70-90 °C for 45 minutes or 1 hour followed by rinsing with water and annealing at 100 °C for 1 hour. Thin films of 0-1% Nb-doped TiO2 with rutile phase on FTO were obtained, which were confirmed through X-ray diffraction analyses and measurements of energy dispersive X-ray spectroscopy (EDS). Scanning electron microscopy observations equipped with EDS revealed that higher growth temperature over 90 °C is required for doping of Nb. While higher concentration of HCl resulted in much amount of Nb-doping. Band gap of rutile TiO2 gradually reduced from 3.3 eV to 3.23 eV through Nb-doping from 0% to 1%, which were estimated from uv-vis absorption spectroscopic analyses. Hall effect measurements by taking van der Pauw method confirmed that 2.26 times increase of the carrier density and 1.78 times enhancement of the conductivity have been achieved in the case of 1% Nb-doping.

Selective Laser Melting (SLM) involves numerous fabrication parameters, the interaction between those parameters determine the final characteristics of the resulting part and because of the latter, it is considered a complex process. Low-density components is one of the main issues of the SLM process, due to the incorrect selection of process parameters. These defects are undesired in high specialized applications (i.e. aerospace, aeronautic and medical industries). Therefore, the characterization of the defects (pores) found in aluminum parts manufacture by SLM and the relationship with fabrication parameters was performed. A robust orthogonal design of experiments was implemented to determine process parameters, and then parts were manufactured in SLM. Relative density of the samples was then characterized using the Archimedes principle and microscopy; the data was then statistically analyzed in order to determine the optimal process parameters. The main purpose of the present research was to establish the best processing parameters of an in-house SLM system, as well as to characterize the pore geometry in order to fully eliminate pores in a future research.

It has been well studied that reliable multicast enables consistency protocols, including Byzantine Fault Tolerant protocols, for distributed systems. However, no transport-layer reliable multicast is used today due to limitations with existing switch fabrics and transport-layer protocols. In this paper, we introduce a layer-4 (L4) transport based on remote direct memory access (RDMA) datagram to achieve reliable multicast over a shared optical medium. By connecting a cluster of networking nodes using a passive optical cross-connect fabric enhanced with wavelength division multiplexing, all messages are broadcast to all nodes. This mechanism enables consistency in a distributed system to be maintained at a low latency cost. By further utilizing RDMA datagram as the L4 protocol, we have achieved a low-enough message loss-ratio (better than one in 68 billion) to make a simple Negative Acknowledge (NACK)-based L4 multicast practical to deploy. To our knowledge, it is the first multicast architecture able to demonstrate such low message loss-ratio. Furthermore, with this reliable multicast transport, end-to-end latencies of eight microseconds or less (< 8us) have been routinely achieved using an enhanced software RDMA implementation on a variety of commodity 10G Ethernet network adapters.

High-index materials such as silicon and III-V compounds have recently gained a lot of interest as a promising material platform for efficient photonic nanostructures. Because of the high refractive index, nanoparticles of such materials support Mie resonances and enable efficient light control and its confinement at the nanoscale. Here we propose a design of nanostructure with multipole resonances where optical nanoantennas are made out of transition metal dichalcogenide, in particular, tungsten disulfide WS2. Transition metal dichalcogenide (TMDCs) possess a high refractive index and strong optical anisotropy because of their layered structure and are promising building blocks for next-generation photonic devices. Strong anisotropic response results in different components of TMDC permittivity and the possibility of tailoring nanostructure optical properties by choosing different axes and adjusting dimensions in design. The proposed periodic array of TMDC nanoantennas can be used for controlling optical resonances in the visible and near-infrared spectral ranges and engineering efficient ultra-thin optical components with nanoscale light confinement.

[K0.5Na0.5NbO3]1−x[BaNi0.5Nb0.5O3−δ]x (KNBNNO, 0 ≤ x ≤ 0.3) films have been fabricated on different substrates for the first time, using a modified chemical solution deposition method. The microstructure, optical properties, ferromagnetism, and substrate effects of KNBNNO films were assessed, and we found that BaNi0.5Nb0.5O3−δ (BNNO) content was a key factor in determining the properties of the final products. The lower band gap of KNBNNO is due to the band-to-band transition from hybridized Ni 3d and O 2p to Nb 4d states. Moreover, with increasing x from 0 to 0.3, the magnetism transition process of the samples from diamagnetism to ferromagnetism may originate from the competition between ferromagnetic exchange interactions in Ni2+–VO2−–Ni2+ and superexchange interactions in Ni2+–Ni2+. Notably, absorption behaviors in the visible light wave band for KNBNNO films have been realized, which makes it possible to use KNBNNO films for perovskite solar cell applications.

LED illumination systems for fluorescence microscopy offer a wealth of benefits in comparison to traditional mercury and metal halide lamps, including ease of use, improved stability, and enhanced control. To fully realize these benefits, it is important to ensure that optical filters are configured correctly, which often can be confusing. However, without the correct filter configuration, experimental conditions can be suboptimal, and results may therefore be inaccurate. This article looks at optical filter setup in more depth, explaining the purpose and benefits of optimal LED filtering.

Morphological characterization and quantification of gold particles by optical image analysis (OIA) and by compositional analysis of microprobes using scanning electron microscope and electron microprobe analysis techniques were carried out on gold grains from the Minvoul area (Archean greenstone belt in Gabon). Large grains of almost pure gold were found throughout a weathering profile, which consisted of saprolite, mottled clay zone, iron duricrust, pisolitic gravels and yellow latosol. In the deeper horizons, gold was dissolved as shown by corrosion features on the surface of particles with average sizes of 2.6Φ and 2.35Φ in the saprolite and mottled clay zones, respectively. The occurrence of secondary gold in the duricrust was indicated by the larger size of the nuggets (average, 1.8Φ), the high fineness (> 995 in average) and the close textural relationship between gold and neoformed iron oxyhydroxides. The uppermost horizons composed of yellow latosol and pisolitic gravels were interpreted as transported materials based on their size distribution (average 0.85Φ and 1.34Φ), sorting and shape parameters. The best morphological parameter to describe the whole weathering profile was found to be the perimeter/area ratio. The highest ratios were recorded in the saprolite (average 0.192 μm−1), and decreased towards the surface (average 0.057 μm−1). The combination of the OIA technique and the microchemical analysis of gold grains allowed us to define specific morphological and compositional characteristics of the gold particles for each horizon. Both methods proved to be of great utility to understand gold concentration, dissolution and dispersion processes in supergene environments.

Aqueous auto-dispersing polyurethane dispersions (PUDs) have recently been reported to form nanoparticulate dispersions at up to 25% by weight. Their incorporation of an ionic-liquid (IL) monomer, 1-hydroxyundecyl-3-methyl imidazolium bromide (HOC11C1ImBr) as a chain-terminating group appears to account for their auto-dispersing ability, and these PUD nanoparticles bear similarity to IL-based nanolatexes that have provided thermodynamically stable aqueous dispersions of nanocarbons. We demonstrate that these HOC11C1ImBr-based PUDs stabilize aqueous graphene dispersions at 1% by weight graphene in ultrasonicated top-down liquid phase exfoliation. Their formation quantitatively follows an analytical model of exfoliation kinetics of layered materials and a stretched exponential kinetic model. Such dispersions are ideally formulated for making nanocomposites composed of similar or compatible PUDs and other condensation polymers.

Macular pigment (MP) confers potent antioxidant and anti-inflammatory effects at the macula, and may therefore protect retinal tissue from the oxidative stress and inflammation associated with ocular disease and ageing. There is a body of evidence implicating oxidative damage and inflammation as underlying pathological processes in diabetic retinopathy. MP has therefore become a focus of research in diabetes, with recent evidence suggesting that individuals with diabetes, particularly type 2 diabetes, have lower MP relative to healthy controls. The present review explores the currently available evidence to illuminate the metabolic perturbations that may possibly be involved in MP’s depletion. Metabolic co-morbidities commonly associated with type 2 diabetes, such as overweight/obesity, dyslipidaemia, hyperglycaemia and insulin resistance, may have related and independent relationships with MP. Increased adiposity and dyslipidaemia may adversely affect MP by compromising the availability, transport and assimilation of these dietary carotenoids in the retina. Furthermore, carotenoid intake may be compromised by the dietary deficiencies characteristic of type 2 diabetes, thereby further compromising redox homeostasis. Candidate causal mechanisms to explain the lower MP levels reported in diabetes include increased oxidative stress, inflammation, hyperglycaemia, insulin resistance, overweight/obesity and dyslipidaemia; factors that may negatively affect redox status, and the availability, transport and stabilisation of carotenoids in the retina. Further study in diabetic populations is warranted to fully elucidate these relationships.

Although the streaked optical pyrometer (SOP) system has been widely adopted in shock temperature measurements, its reliability has always been of concern. Here, two calibrated Planckian radiators with different color temperatures were used to calibrate and verify the SOP system by comparing the two calibration standards using both multi-channel and single-channel methods. A high-color-temperature standard lamp and a multi-channel filter were specifically designed for the measurement system. To verify the reliability of the SOP system, the relative deviation between the measured data and the standard value of less than 5% was calibrated out, which demonstrates the reliability of the SOP system. Furthermore, a method to analyze the uncertainty and sensitivity of the SOP system is proposed. A series of laser-induced shock experiments were conducted at the ‘Shenguang-II’ laser facility to verify the reliability of the SOP system for temperature measurements at tens of thousands of kelvin. The measured temperature of the quartz in our experiments agreed fairly well with previous works, which serves as evidence for the reliability of the SOP system.

Organic light emitting diodes (OLEDs) have drawn great attention owing to their potential applications in high-quality flat display panels and smart solid-state lighting. Over the last three decades, numerous approaches have been made on material design and device physics to achieve high-efficiency and long-lifespan. Herein, we report a novel tactic to employ solution-processed hybrid metal oxide, molybdenum trioxide-tungsten trioxide (MoO3:WO3), as an efficient and stable hole injection/transport (HIL/HTL) and electron blocking layer for efficient OLEDs. By using phosphorescent orange-red emitter tris(2-phenylquinoline)-iridium(III) Ir(2-phq)3, MoO3:WO3 HIL based OLED device exhibits a power efficiency of 27.7 lm W-1 and 22.9 lm W-1 at 100 and 1000 cd m-2, respectively, which are 89% and 157% higher than that of conventional OLED device consisting of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) as an HIL. Moreover, the resulted device also displays 1.6 times lower turn-on voltage and 3.0 time higher brightness as compare to other counter part. The higher device performances of OLED device may be attributed to robust hole transporting ability, balanced charge carrier in the recombination zone and non-acidic nature of designed HIL. Our results demonstrate that a novel alternative approach based on transition metal oxide hybrid HIL/HTL as a substitute to PEDOT:PSS for high-efficiency solution process OLEDs.