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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.

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At least 1,081 records · Page 60
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Coal emissions adverse human health effects associated with ultrafine/nano-particles role and resultant engineering controls

There are multiple elements which enable coal geochemistry: (1) boiler and pollution control system design parameters, (2) temperature of flue gas at collection point, (3) feed coal and also other fuels like petroleum coke, tires and biomass geochemistry and (4) fuel feed particle size distribution homogeneity distribution, maintenance of pulverisers, etc. Even though there is a large number of hazardous element pollutants in the coal-processing industry, investigations on micrometer and nanometer-sized particles including their aqueous colloids formation reactions and their behaviour entering the environment are relatively few in numbers. X-ray diffraction (XRD), High Resolution-Transmission Electron microscopy (HR-TEM)/ (Energy Dispersive Spectroscopy) EDS/ (selected-area diffraction pattern) SAED, Field Emission-Scanning Electron Microscopy (FE-SEM)/EDS and granulometric distribution analysis were used as an integrated characterization techniques tool box to determine both geochemistry and nanomineralogy for coal fly ashes (CFAs) from Brazil´s largest coal power plant. Ultrafine/nano-particles size distribution from coal combustion emissions was estimated during the tests. In addition the iron and silicon content was determined as 54.6% of the total 390 different particles observed by electron bean, results aimed that these two particles represent major minerals in the environment particles normally. These data may help in future investigations to asses human health actions related with nano-particles.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Effect of microstructure and crystallographic texture on mechanical anisotropy of Ti-Nb microalloyed hot rolled 800 MPa HSLA steel

Highlights: • Anisotropy in yield strengthis attributed to the relatively stronger {332} . • γ-fiber with counter-balancing {111} and {111} could not induce anisotropy. • The maximum CVN value at 0° is attributed to the higher fraction of {113} and {112} . • The large anisotropy in CVN value, ~ 100 J is observed due to a weaker {332} and {554} . - Abstract: The impact toughness of a Ti+Nb HSLA steel plate, conventionally hot rolled in the austenitic region, were measured at four different directions at 0 °C, −20 °C and −40 °C respectively. The microstructure was characterised using light optical microscope, scanning electron microscope (SEM) followed by evaluation of hot rolled texture using X-ray diffraction (XRD) and orientation distribution function (ODF) obtained from electron back-scattered diffraction (EBSD). The anisotropy in the yield strength (YS) and Charpy impact toughness (CVN) were examined in the light of orientation distribution function (ODF) obtained from EBSD. The skeleton lines, showing intensity distribution, f(g), of the fcc-to-bcc transformation texture, namely the α-fiber (<110>∥ RD), the γ-fiber (<111>∥ ND) and ε-fiber (<110>∥ TD) are considered to explain the observed anisotropy along with microstructural features. The major components like, {112}<110>, {113}<110>, {332}<113>, {111}<112> and {111}<110>, their relative intensity distribution, are found to cause the observed anisotropy in yield strength and impact toughness. A stronger presence of {113}<110> component of the α-fiber over relatively weaker {332}<113> component of the ε-fiber further augments the observed toughness anisotropy. In absence of any microstructural banding, strong the presence of {113}<110> and {112}<110> can also cause delamination in ductile fracture mode.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Corrosion Behavior of Q235 Steel Exposed in Deepwater of South China Sea

For the first time, the corrosion behavior of Q235 steel in 1200, 2000 and 3000 m deepwater of South China Sea for 0.5 year was reported in this study. The corrosion morphology and corrosion products properties were investigated using different techniques, such as 3D optical microscope, scanning electron microscope, x-ray diffraction analyzer and electrochemical impedance spectroscopy. The main environmental factors influencing the corrosion rate of Q235 in deep sea were discussed by applying gray relational analysis. The results indicated that uniform thinning occurred after exposure. A large number of tiny pits were distributed under the corrosion products with a two-layer structure. The corrosion rate and average pitting depth of samples exposed at 2000 m were lower than those exposed at 1200 and 3000 m, and the main environmental factors determining the variation of corrosion rate at different depths were temperature and dissolved oxygen concentration. Hydrostatic pressure had slight effect on the corrosion rate of Q235 steel, but promoted the formation of a more uniform corrosion morphology.

36 MATERIALS SCIENCE↗
DOE OSTI2015

SnO{sub 2} films: In-situ template-sacrificial growth and photovoltaic property based on SnO{sub 2}/poly(3-hexyl-thiophene) for hybrid solar cell

Highlights: • SnO{sub 2} nanocrystals/thin films were fabricated on ITO glass substrate from preformed SnS thin film as sacrificial template. • The SnO{sub 2} film and SnO{sub 2}/P3HT was characterized by several techniques. • The new hybrid solar cell device was based on the hybrid thin film of SnO{sub 2} NCs and P3HT composites. - Abstract: we described a facile in-situ wet chemical method to prepare SnO{sub 2} thin film on ITO glass substrate from preformed SnS thin film as sacrificial template. The chemical conversion process of SnS to SnO{sub 2} was studied. The SnO{sub 2} film and SnO{sub 2}/P3HT was characterized by several techniques, such as powder X-ray diffract meter (XRD), Raman spectrometer, scanning electron microscope (SEM), atomic force microscope (AFM) and UV–vis spectrophotometer in detail. The new SnO{sub 2}/P3HT hybrid solar cell device showed an open-circuit voltage of 0.185 V, a short-circuit current density of 0.366 mA/cm{sup 2} and a fill factor of 0.247, corresponding to a power conversion efficiency of 0.0167%.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Fabrication and characterization of metal–semiconductor–metal ultraviolet photodetector based on rutile TiO{sub 2} nanorod

The fabrication and characterization of a metal–semiconductor–metal ultraviolet photodetector are studied. The photodetector is based on TiO{sub 2} nanorods (NRs) grown on p-type (1 1 1)-oriented silicon substrate seeded with a TiO{sub 2} layer is synthesized by radio frequency reactive magnetron sputtering. A chemical bath deposition is used to grow TiO{sub 2} NRs on Si substrate. The structural and optical properties of the obtained sample are analyzed by using X-ray diffraction and field emission-scanning electron microscopy. Results show a tetragonal rutile structure of the synthesized TiO{sub 2} NRs. Optical properties are further examined using photoluminescence spectroscopy. A sharp and high-intensity UV peak at 367 nm is observed in comparison with visible defect peaks centered at 432 and 718 nm. Upon exposure to 365 nm light (2.3 mW/cm) at 5 V bias, the device displays 76.06 × 10{sup 2} sensitivity, internal photodetector gain of 77.06, photocurrent of the device is 2.62 × 10{sup −5} A and photoresponse peak of 69.7 mA/W. The response and recovery times are calculated as 18.5 and 19.1 ms upon illumination to a pulse UV light (365 nm, 2.3 mW/cm{sup 2}) at 5 V applied bias. These results demonstrate that the fabricated high-quality photodiode is a promising candidate as a low-cost UV photodetector for commercially-integrated photoelectronic applications.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Microwave-assisted synthesis of Mn{sub 3}O{sub 4} nanoparticles@reduced graphene oxide nanocomposites for high performance supercapacitors

Highlights: • Mn{sub 3}O{sub 4}@rGO nanocomposites were prepared by one-step microwave-assisted method. • The growth of Mn{sub 3}O{sub 4} and the reduction of graphene oxide occurred simultaneously. • Specific capacitance of the nanocomposite is higher than those of rGO and Mn{sub 3}O{sub 4}. • The nanocomposites have good rate capability and cycling stability. - ABSTRACT: One-step microwave-assisted synthetic route for the fabrication of Mn{sub 3}O{sub 4} nanoparticles@reduced graphene oxide (Mn{sub 3}O{sub 4}@rGO) nanocomposites has been demonstrated. The morphological structures of the nanocomposites are characterized by Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray diffraction (XRD), thermogravimetric analyses (TGA), and scanning electron microscopy (SEM), respectively. All of the results indicate that the microwave-assisted synthesis results in the growth of Mn{sub 3}O{sub 4} and the reduction of graphene oxide simultaneously in ethylene glycol-water system. The specific capacitance of the as-prepared Mn{sub 3}O{sub 4}@rGO nanocomposite is higher than those of rGO and pure Mn{sub 3}O{sub 4}, which indicates the synergetic interaction between rGO and Mn{sub 3}O{sub 4}. The nanocomposites also have good rate capability and cycling stability in electrochemical experiments. This facile technique may be extended to the large scale and cost effective production of other composites based on graphene and metal oxide for many applications.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2018

Plasmonic Hybrid Biocomposite as an Effective Substrate for Detection of Biomolecules by Surface-Enhanced Raman Spectroscopy

The enhancement of the Raman light scattering signal from the surface of the porous hybrid biocomposites based on polyhydroxybutyrate (PHB), calcium carbonate (CaCO{sub 3}), and nanoplasmonic Ag particles is investigated. Based on PHB, fibrous scaffolds are obtained by the electrospinning technique. The fibrous scaffolds have been covered by CaCO{sub 3} and Ag nanoparticles by means of mineralization in salt solutions and Ag reduction reaction. Successful formation of the CaCO{sub 3} and Ag nanoparticles on the scaffold surface has been confirmed by the data of scanning electron microscopy, x-ray diffraction analysis, and infrared spectroscopy. Surface-enhanced Raman spectroscopy (SERS) of the obtained sample surface has demonstrated a significant enhancement of the Rhodamine 6G signal (E{sub f} > 10{sup 5}) in comparison with the reference sample where the analyte concentration and the laser power were 100 times higher. Thus, the present research has confirmed prospects for the application of biocomposites based on polyhydroxybutyrate for detection and investigation of biomolecules by the SERS method.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Toward a Biocompatible and Degradable Battery Using a Mg-Zn-Zr Alloy with β-Tricalcium Phosphate Nanocoating as Anode

A biocompatible β-tricalcium phosphate (β-TCP) nanorod coating on Mg-3 wt.%Zn-0.8 wt.%Zr alloy (MZZ) was fabricated by a chemical solution process. The microstructure and corrosion resistance of β-TCP coating on MZZ were studied using scanning electron microscopy, x-ray diffraction, and potentiodynamic polarization. β-TCP-MZZ was used as the anode for Mg battery with simulated body fluid directly acting as the electrolyte. The experimental results indicate that the β-TCP nanorod coating formed on the surface of MZZ alloy protects the matrix and improves the corrosion resistance of MZZ alloy. The Mg battery showed a voltage of 1.05 V for up to 75 days and continued to discharge for 90 days until 0.7 V at 100 μA/cm{sup 2}. This indicates potential practical importance of biodegradable batteries.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Dual-source evaporation of silver bismuth iodide films for planar junction solar cells

Non-toxic and air-stable silver bismuth iodide semiconductors are promising light absorber candidates for photovoltaic applications owing to a suitable band gap for multi- or single-junction solar cells. Recently, solution-based film fabrication approaches for several silver bismuth iodide stoichiometries have been investigated. The current work reports on a facile and reproducible two-step coevaporation/annealing approach to deposit compact and pinhole-free films of AgBi 2 I 7 , AgBiI 4 and Ag 2 BiI 5 . X-ray diffraction (XRD) in combination with scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDX) analysis reveals formation of pure cubic (Fd$\bar{3}$m) with combining macron]m) phase AgBi 2 I 7 , cubic (Fd$\bar{3}$m) or rhombohedra (R$\bar{3}$m with combining macron]m) phase AgBiI 4 , each with >3 μm average grain size, or the rhombohedral phase (R$\bar{3}$m) Ag 2 BiI 5 with >200 nm average grain size. A phase transition from rhombohedral to cubic structure is investigated via temperature-dependent X-ray diffraction (TD-XRD). Planar-junction photovoltaic (PV) devices are prepared based on the coevaporated rhombohedral AgBiI 4 films, with titanium dioxide (TiO 2 ) and poly(3-hexylthiophene) (P3HT) as electron- and hole-transport layers, respectively. Finally, the best-performing device exhibited a power conversion efficiency (PCE) of as high as 0.9% with open-circuit voltage (VOC) > 0.8 V in the reverse scan direction (with significant hysteresis).

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Effects of organic additives on calcium hydroxide crystallisation during lime slaking

Highlights: • Sucrose and lignosulfonate reduce the crystallite size of Ca(OH){sub 2}. • Lime slaking in sucrose solutions leads to Ca(OH)2 with irregular shape. • Lime slaking in presence of lignosulfonate leads to plate-like Ca(OH){sub 2} crystals. • Effects of additives are enhanced when introduced before slaking. • Additives stabilise the unstable edge faces of Ca(OH){sub 2} during ageing. Organic compounds, often used in cement systems as admixtures, may affect the crystallisation and carbonation kinetics of Ca(OH){sub 2}, an important phase of hydrated cement. Here, we investigated changes in Ca(OH){sub 2} morphology in the presence of 3 organic compounds, commonly encountered in cement and lime-based materials: sucrose, pectin and calcium lignosulfonate. The additives were introduced either before or after lime slaking to determine the influence of temperature. Ca(OH){sub 2} crystals and supernatant solutions were characterised at time of slaking and after 6 months of ageing using scanning electron microscopy, X-ray diffraction and optical emission spectroscopy. Our results indicate that the morphology of Ca(OH){sub 2} crystals is modified by the characteristics of the organic molecules which promote formation of Ca(OH){sub 2} with habits that can result in faster carbonation, an effect that is detrimental to cement used in reinforced concrete. These effects are enhanced when the additives are introduced before slaking, likely as a result of thermal degradation.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Formation of Zinc-Oxide Nanorods by the Precipitation Method

Zinc oxide (ZnO) rod-shaped nanoparticles are produced by the precipitation method upon the hydrolysis of zinc-nitrate hexahydrate (Zn(NO{sub 3}){sub 2} · 6H{sub 2}O) in the presence of hexamethylenetetramine (C{sub 6}H{sub 12}N{sub 4}). The effect of various parameters on the ZnO-nanorod size and shape is shown. The ZnO nanopowders produced are studied by scanning electron microscopy and X-ray diffraction analysis. The adhesive and mechanical properties of samples containing ZnO nanoparticles and microparticles as additions are studied.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Preparation of Ni—Mo/γ-Al{sub 2}O{sub 3} Catalysts by Vacuum Impregnation and Their Use for Hydrodesulfurization of Dibenzothiophene

A dual metal Ni—Mo/γ-Al{sub 2}O{sub 3} catalyst was prepared by saturated impregnation and H{sub 2} reduction pretreatment on γ-Al{sub 2}O{sub 3} support with Ni as the active component and Mo as the promoter. The support and catalysts were characterized using x-ray diffraction, hydrogen temperature-programmed reduction, and scanning electron microscopy. The catalytic properties for the reaction of dibenzothiophene (DBT) were investigated in a high-pressure reactor. The hydrodesulfurization (HDS) activity was comparable with those of advanced desulfurization catalysts FHUDS-5 and FHUDS-6. The Ni—Mo catalyst had excellent dispersion characteristics on the support. Synergism between Ni and Mo was greatest at a Ni/Mo molar ratio of 2:1. The DBT conversion on Ni—Mo/γ-Al{sub 2}O{sub 3} catalyst reached 100% at a reaction temperature of 300°C, pressure of 4 MPa, and reaction time of 150 min. The Ni—Mo/γ-Al{sub 2}O{sub 3}atalyst was significantly more active than the aforementioned two commercial FHUDS catalysts for HDS of DBT.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Structural and optical properties of silicon-carbide nanowires produced by the high-temperature carbonization of silicon nanostructures

Silicon-carbide (SiC) nanowire structures 40–50 nm in diameter are produced by the high-temperature carbonization of porous silicon and silicon nanowires. The SiC nanowires are studied by scanning electron microscopy, X-ray diffraction analysis, Raman spectroscopy, and infrared reflectance spectroscopy. The X-ray structural and Raman data suggest that the cubic 3C-SiC polytype is dominant in the samples under study. The shape of the infrared reflectance spectrum in the region of the reststrahlen band 800–900 cm{sup –1} is indicative of the presence of free charge carriers. The possibility of using SiC nanowires in microelectronic, photonic, and gas-sensing devices is discussed.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Dye sensitized solar cell applications of CdTiO{sub 3}–TiO{sub 2} composite thin films deposited from single molecular complex

A heterobimetallic complex [Cd{sub 2}Ti{sub 4}(μ-O){sub 6}(TFA){sub 8}(THF){sub 6}]·1.5THF (1) (TFA=trifluoroacetato, THF=tetrahydrofuran) comprising of Cd:Ti (1:2) ratio was synthesized by a chemical reaction of cadmium (II) acetate with titanium (IV) isopropoxide and triflouroacetic acid in THF. The stoichiometry of (1) was recognized by single crystal X-ray diffraction, spectroscopic and elemental analyses. Thermal studies revealed that (1) neatly decomposes at 450 °C to furnish 1:1 ratio of cadmium titanate:titania composite oxides material. The thin films of CdTiO{sub 3}–TiO{sub 2} composite oxides were deposited at 550 °C on fluorine doped tin oxide coated conducting glass substrate in air ambient. The micro-structure, crystallinity, phase identification and chemical composition of microspherical architectured CdTiO{sub 3}–TiO{sub 2} composite thin film have been determined by scanning electron microscopy, X-ray diffraction, Raman spectroscopy and energy dispersive X-ray analysis. The scope of composite thin film having band gap of 3.1 eV was explored as photoanode for dye-sensitized solar cell application. - Graphical abstarct: Microspherical designed CdTiO{sub 3}–TiO{sub 2} composite oxides photoanode film has been fabricated from single source precursor [Cd{sub 2}Ti{sub 4}(μ-O){sub 6}(TFA){sub 8}(THF){sub 6}]·1.5THF via aerosol assisted chemical vapor deposition technique for dye sensitized solar cell application. - Highlights: • Synthesis and characterization of a heterobimetallic Cd–Ti complex. • Fabrication of CdTiO{sub 3}–TiO{sub 2} thin film photoelectrode. • Application as dye sensitized photoanode for solar application.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Structural Modification of Starch Nanoparticles Via Graft Copolymerization Using KMnO{sub 4}, HClO{sub 4} and HNO{sub 3} Redox Pair

The novelty addressed here is commenced with a view to use our formerly prepared starch nanoparticles (SNPs) of size around 80–100 nm as a starting substrate for grafting meth acrylic acid (MAA) using KMnO{sub 4}, HClO{sub 4} in presence of HNO{sub 3} as innovative redox pair in aqueous medium. This was done to see the effect of SNPs with respect to well-dispersed nanosized particles, large surface areas, biodegradability and reactivity on the rate and extent of grafting. Besides; maximize the graft yield and graft reaction efficiency and reduce the homopolymer formation to lower extent. This could be accomplished via an in-depth assessment into the chief factors affecting the polymerization reaction such as initiator, monomer, SNPs and acid concentrations, time and temperature of polymerization, and liquor ratio. The results obtained indicate that the magnitude of the polymer yield including graft yield, graft reaction efficiency and homopolymer formation are determined by these factors. The structure of the resultant copolymers was confirmed instrumentally by Fourier transforms infrared spectroscopy; while both the surface morphology, crystalline structure and thermal properties were characterized by scanning electron microscopy, X-ray diffraction and thermal gravimetric analysis. Furthermore, the resultant copolymers were evaluated as environmental remediation materials via cadmium ions and cationic dyes removal from their solutions with different extent; in addition to higher swelling and chemical resistance in water as polar solvent and hydrochloric acid as acidic solution. The anticipated mechanisms involved in the synthesis are reported.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2015

Reduced graphene oxide/CeO{sub 2} nanocomposite with enhanced photocatalytic performance

In this work, reduced graphene oxide /cerium oxide (RGO/CeO{sub 2}) nanocomposite was synthesized by in situ reduction of cerium nitrate Ce(NO{sub 3}){sub 3}·6H{sub 2}O in the presence of graphene oxide by hydrazine hydrate (N{sub 2}H{sub 4}.H{sub 2}O). The intrinsic characteristics of as-prepared nanocomposite were studied using powder x-ray diffraction (XRD), Raman spectroscopy and field-emission scanning electron microscopy (FESEM). The photocatalytic degradation of methylene blue (MB) was employed as a model reaction to evaluate the photocatalytic activity of the RGO/CeO{sub 2} nanocomposite. The as-obtained RGO/CeO{sub 2} nanocomposite displays a significantly enhanced photocatalytic degradation of MB dye in comparison with bare CeO{sub 2} nanoparticles under sunlight irradiation, which can be attributed to the improved separation of electron-hole pairs and enhanced adsorption performance due to presence of RGO.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2023

Analysis of furnace contamination on superconducting radio frequency niobium using secondary-ion mass spectrometry

Detection of surface contamination on niobium materials used in superconducting radio frequency (SRF) applications is difficult due to quantitative sensitivity and near-atomic depth resolution needed. Inspection of samples known to have experienced surface contamination was found to have inconsistent nitride coverage after high-temperature nitrogen gas exposure (“doping”). Here we compare contaminating species found on samples treated in several different vacuum furnaces, both “exposed” directly in the chamber and “protected” by containment shielding from evaporative sources with “furnace caps.” Typically, furnace caps are used to impede contamination from reaching the interior surface of cavities during the high-temperature vacuum bake that immediately precedes exposure to nitrogen gas. Although, to date, little is known about the effectiveness of these caps, SIMS results showed that they were effective in limiting contamination arising from the furnace environment. Inspection of sample surfaces by SEM showed a lack of nitrides present on contaminated specimens. TEM with energy dispersive spectroscopy performed on these samples revealed that a carbon-rich layer now existed, indicating that a relatively high contaminant load prevents the nucleation and growth of surface nitrides, while thus inhibiting interstitial nitrogen uptake. Except in extreme cases, subsequent removal of the top several micrometers of the surface via electropolishing appears to effectively eliminate any strong influence on the subsequent SRF cavity performance. With the absence of furnace cleaning, carbon contamination was found to be nearly 10× higher for protected nitrogen-doped and electropolished samples, with minimal metallic contamination detected for both processes. SIMS analysis was also performed to compare the cleanliness of samples fully prepared by such nitrogen “doping” with those prepared by a related process, involving the dissolution of niobium surface oxide and diffusion of oxygen into the surface. This oxygen doping or alloying process offers attractive advantages.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2019

Electromagnetic Wave-Absorbing Properties of Steel Slag

This research explores the electromagnetic radiation protection function of steel slag for use as a building material. Scanning electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy and Mössbauer spectroscopy were used to analyze the chemical composition and mineralogical phase of steel slag powder. Electromagnetic parameters of the samples were analyzed and discussed in detail for the frequency range of 1-18 GHz. We found that steel slag had the electromagnetic wave-absorbing property due to electric components (such as FeO and carbon powder) and magnetic components [such as magnetite (Fe{sub 3}O{sub 4}) and hematite (α-Fe{sub 2}O{sub 3})]; electric loss was far greater than magnetic loss. With the increasing milling time, the electric and magnetic properties were increased. The calculated reflectivity curve of steel slag powder epoxide resin–matrix composite at a thickness of 10 mm had several interference peaks, and the absorbing properties increased gradually with increasing frequency. Moreover, the minimum reflectivity was − 21 dB (Decibel) at 13 GHz (Gigahertz). The steel slag powder cement-based composite showed electromagnetic wave-absorbing properties at 10-18 GHz, and the greatest absorption of the 25 mm sample reached 11.5 dB; therefore, the steel slag shows promise as a building material for electromagnetic protection.

36 MATERIALS SCIENCE↗