Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “REFLECT”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,099 records · Page 61
All sourcesNASA NTRSDOE OSTI
DOE OSTI2016

Anti-reflective and anti-soiling coatings for self-cleaning properties

The disclosure discloses abrasion resistant, persistently hydrophobic and oleophobic, anti-reflective and anti-soiling coatings for glass. The coatings described herein have wide application, including for example the front cover glass of solar modules. Methods of applying the coatings using various apparatus are disclosed. Methods for using the coatings in solar energy generation plants to achieve greater energy yield and reduced operations costs are disclosed. Coating materials are formed by combinations of hydrolyzed silane-base precursors through sol-gel processes. Several methods of synthesis and formulation of coating materials are disclosed.

14 SOLAR ENERGY↗
DOE OSTI2016

High gain durable anti-reflective coating with oblate voids

Disclosed herein are single layer transparent coatings with an anti-reflective property, a hydrophobic property, and that are highly abrasion resistant. The single layer transparent coatings contain a plurality of oblate voids. At least 1% of the oblate voids are open to a surface of the single layer transparent coatings.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Anti-reflective and anti-soiling coatings with self-cleaning properties

Disclosed herein is a coated glass element including a glass component and a coating adhered to the glass component through siloxane linkages, the coating having at least one of an anti-reflective property, a high abrasion resistance property and a hydrophobic property, wherein the coating comprises a dried gel formed from at least one hydrolyzed alkoxysilane-based sol and at least one hydrolyzed organosilane-based sol.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Solar power conversion system with directionally- and spectrally-selective properties based on a reflective cavity

Solar power conversion system. The system includes a cavity formed within an enclosure having highly specularly reflecting in the IR spectrum inside walls, the enclosure having an opening to receive solar radiation. An absorber is positioned within the cavity for receiving the solar radiation resulting in heating of the absorber structure. In a preferred embodiment, the system further contains an energy conversion and storage devices thermally-linked to the absorber by heat conduction, convection, far-field or near-field thermal radiation.

14 SOLAR ENERGY↗
DOE OSTI2016

Anti-reflective articles with nanosilica-based coatings and barrier layer

An article including a transparent substrate having an anti-reflective, structured surface and a sintered coating including a porous network of silica nanoparticles thereon, wherein the silica nanoparticles are bonded to adjacent silica nanoparticles, wherein the structured substrate further includes a backing face, and a moisture barrier layer bonded to the backing face of the structured substrate.

14 SOLAR ENERGY↗
DOE OSTI2022

Reflective long period grating

A reflection mode sensor system may include an optical fiber core and an optical fiber cladding. A first long period grating (LPG) may be positioned along the optical fiber core having a first grating period, a second LPG may be positioned along the optical fiber core having a second grating period, and a third LPG may be positioned along the optical fiber core having a third grating period. The grating periods may enable sensing of multiple parameters simultaneously. A metal coating may be applied to an end facet of the combined optical fiber core and optical fiber cladding. The metal coating may also cover a side surface of the optical fiber cladding along a length from the end facet. The metal coating may include a paste applied to the optical fiber core and the optical fiber cladding, where the paste has been cured, and includes a metal.

47 OTHER INSTRUMENTATION↗
DOE OSTI2022

Wavelength-selective specularly reflecting photovoltaic module and manufacture thereof

A photovoltaic module comprises a plurality of photovoltaic cells, and a polymeric film positioned on an incident light side of the plurality of photovoltaic cells, wherein the polymeric film transmits a range of wavelengths of the incident light spectrum and specularly reflects wavelengths outside of the range. An encapsulant layer is in contact with the polymeric film. The polymeric film may have a first surface area larger than a second surface area of the layer of photovoltaic cells. The polymeric film may have one or more through-holes so that encapsulant can penetrate through the through-holes at elevated temperature during lamination thereby bonding to a front glass of the photovoltaic module.

14 SOLAR ENERGY↗
DOE OSTI2022

Reflective metasurfaces for broadband terahertz linear-to-circular polarization conversion and circular dichroism spectroscopy

Metasurface polarization convertors permit conversion of an input linear polarization to right- or left-handed circular polarization based on the orientation of the input linear polarization, over a broad bandwidth and with high efficiency. The reflected circular polarizations can be used to evaluate samples for circular dichroism. A THz time-domain detection provides a time domain terahertz signal that is Fourier transformed to produce a THz circular dichroism spectrum.

Chen, Hou-Tong↗
DOE OSTI2023

Total internal reflection enabled wide-field Coherent anti-Stokes Raman scattering microscopy

A system is provided. The system has a femtosecond oscillator to generate pulses used for pump and probe beams. A photonic crystal fiber is disposed in a path of the probe beam and produces pulses for a chirped probe beam. A high NA objective receives the pump and the chirped probe beam, redirects the received beams through a dielectric substrate towards an interface between a sample and the dielectric substrate to cause total internal reflection (TIR) at the sample-substrate interface, and produces corresponding evanescent waves in a portion of the sample adjacent to the sample-substrate interface, and collects a backward-propagating beam of pulses of responsive light. The portion of the sample illuminated by the evanescent waves emits responsive light. The dielectric substrate is transparent to the responsive light, the pump and the chirped probe beam. An image is produced having a specific image size using the received backward-propagating beam.

Doughty, Benjamin L.↗
DOE OSTI2023

An Alternative to Solution Experiments for Nuclear Data Validation: Reflection and Interaction of Juxtaposed Uranium (RAIJU) Experiment Design

The need for solution experiments was thoroughly discussed at the recent NCERC (National Criticality Experiments Research Center) Futures Meeting in September 2022 for multiple applications including criticality safety, training, and nuclear data. However, this capability does not exist anywhere in the United States. NCERC, located at the Nevada National Security Site and operated by LANL (Los Alamos National Laboratory) is the only general-purpose critical experiments laboratory in the United States. However, solution experiments are not authorized at NCERC, and obtaining that authorization would be too time consuming and costly to happen in the foreseeable future. An alternative is needed – an experimental configuration with the homogeneity of liquid experiments, but without being a liquid. This project, Reflection and Interaction of Juxtaposed Uranium (RAIJU) will fill the gap in capability within LANL, the U.S. Department of Energy, and the international community and will support current and future nuclear material processing needs.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2023

Improvements in Reflected Target Non-intrusive Assessment (ReTNA)

Accurate optical surfaces are a primary driver of concentrated solar power plant performance. Errors in pointing and tracking mirrors, the canting of individual mirror facets, and the surface slope of the mirror itself can be caused by errors during assembly, transportation, wind loading, gravity, and many other sources. The tools that exist to measure these error sources today largely rely on fringe deflectometry (SOFAST, QDec, others), or photogrammetry with targets attached to the mirror surface. In 2022, NREL presented a new indoor optical measurement system to measure fully assembled heliostats during development and on the assembly line for quality assurance purposes, which has undergone significant development in the last year, including the installation of a new, larger laboratory setup. This system, called ReTNA (Reflected Target Non-intrusive Assessment), uses a printed pattern as a deflectometry target. Using printed pattern features as deflectometry targets instead of fringes allows the software to measure the surface slope in two dimensions, eliminating the need to for changing, projected targets. In the last year, NREL's ReTNA tool has been adapted to use a tall, thin target, that only spans one dimension of the mirror, and a camera moving on an automatic track system. We will present these new developments, including the new setup, target patterns, software methodology for fast, automatic optical analysis, and important lessons learned throughout the process. ReTNA results will be compared to established tools, to establish the uncertainty of this new method. ReTNA leverages recent improvements in computer vision and photogrammetry to remove as much careful calibration from the setup process as possible, making the tool low cost, simple, and portable. While it will not achieve the resolution of a fringe deflectometry system, its advantages make it well suited for CSP evaluation, and allow it to fill a different industry need.

concentrating solar power↗
DOE OSTI2017

Characteristics of concrete reflection of {sup 235}U systems

Water reflection is considered in nuclear criticality safety evaluations because it is readily available and easily forms a close-fitting reflector around fissile material. Concrete is commonly encountered in industrial environments and can be a more effective reflector than water. A comprehensive study using 32 concrete compositions derived from an extensive literature survey was done for the three basic one-dimensional geometries used in radiation transport codes (spherical, infinite length cylindrical, and infinite extent slab) using a {sup 235}U metal/water fissile mixture. The concentration/moderation range over which criticality is possible was spanned, and the change in k{sub eff} per unit change in element atomic number density for various concrete composition elements was computed to determine the relative effect of each element on neutron multiplication. The results show that: -1) the most effective reflector is not the same for each geometry; -2) in general, for each geometry, Δk{sub eff}/ΔN has similar values for {sup 235}U concentrations >0.200 g/cm{sup 3}; and -3) for {sup 235}U concentrations < 0.200 g/cm{sup 3}, the value of Δk{sub eff}/ΔN diminishes toward zero.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2016

Subcritical Benchmark of the BeRP Ball Reflected by Tungsten

In September 2012, eight subcritical configurations were measured with the clad a-phase plutonium sphere known as the Beryllium-Reflected Plutonium (BeRP) ball at the National Criticality Experiments Research Center (NCERC). The configurations had varying tungsten thicknesses including: 0 (bare), 0.5, 1.0, 1.5, 2.0, 2.5, 2.75, and 3.0 inches. Measurements were conducted to provide subcritical benchmark data. This work includes measured and simulated results from the International Handbook of Evaluated Criticality Safety Benchmark Experiments (ICSBEP) evaluation. (authors)

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗