β-Sialon:Eu2+ has been reported to be the most promising narrow-band green phosphor for wide color gamut LCD backlights, but the coexistence of the Eu3+ luminescence killer with the Eu2+ luminescence center limits its luminescence performance to a great extent. In this study, we propose a direct reduction strategy to successfully realize the reduction of Eu3+ to Eu2+ and, finally, increase the effective concentration of Eu2+ in the crystal lattice and greatly minimize the amount of Eu3+ on the particle surface. As a result, the luminescence of treated β-sialon:Eu2+ is enhanced by 2.3 times, and the internal quantum efficiency significantly increases from 52.2 to 96.5%. The mechanisms for such large enhancements in luminescence are clarified by investigating the microstructure, luminescence spectra, valence state, concentration, and distribution of Eu using a variety of chemical analyses. We find that the low efficiency is ascribed to the coexistence of the Eu3+ luminescence killer with the Eu2+ luminescen...

Achieving High Quantum Efficiency Narrow-Band β-Sialon:Eu2+ Phosphors for High-Brightness LCD Backlights by Reducing the Eu3+ Luminescence Killer

https://onlinelibrary.wiley.com/doi/epdf/10.1002/srin.201900108

Reduction of Iron Oxides with Hydrogen—A Review

Reaction kinetics of reduction and oxidation of metal oxides for hydrogen production

The failure of Viking Lander thermal volatilization (TV) (without or with thermal degradation)–gas chromatography (GC)–MS experiments to detect organics suggests chemical rather than biological interpretations for the reactivity of the martian soil. Here, we report that TV–GC–MS may be blind to low levels of organics on Mars. A comparison between TV–GC–MS and total organics has been conducted for a variety of Mars analog soils. In the Antarctic Dry Valleys and the Atacama and Libyan Deserts we find 10–90 μg of refractory or graphitic carbon per gram of soil, which would have been undetectable by the Viking TV–GC–MS. In iron-containing soils (jarosites from Rio Tinto and Panoche Valley) and the Mars simulant (palogonite), oxidation of the organic material to carbon dioxide (CO2) by iron oxides and/or their salts drastically attenuates the detection of organics. The release of 50–700 ppm of CO2 by TV–GC–MS in the Viking analysis may indicate that an oxidation of organic material took place. Therefore, the martian surface could have several orders of magnitude more organics than the stated Viking detection limit. Because of the simplicity of sample handling, TV–GC–MS is still considered the standard method for organic detection on future Mars missions. We suggest that the design of future organic instruments for Mars should include other methods to be able to detect extinct and/or extant life.

https://www.pnas.org/content/pnas/103/44/16089.full.pdf

The limitations on organic detection in Mars-like soils by thermal volatilization-gas chromatography-MS and their implications for the Viking results.

Kinetics and mechanisms of direct reduction of iron ore-biomass composite pellets with hydrogen gas

Effect of gas composition on the kinetics of iron oxide reduction in a hydrogen production process

Cycling effects on the methane regeneration kinetics of CuO/γ-Al2O3 sorbent

It is expected that in the 21st century the Nation will continue to rely on fossil fuels for electricity, transportation, and chemicals. It will be necessary to improve both the process efficiency and environmental impact performance of fossil fuel utilization. GE Global Research has developed an innovative fuel-flexible Unmixed Fuel Processor (UFP) technology to produce H{sub 2}, power, and sequestration-ready CO{sub 2} from coal and other solid fuels. The UFP module offers the potential for reduced cost, increased process efficiency relative to conventional gasification and combustion systems, and near-zero pollutant emissions including NO{sub x}. GE Global Research (prime contractor) was awarded a contract from U.S. DOE NETL to develop the UFP technology. Work on this Phase I program started on October 1, 2000. The project team includes GE Global Research, Southern Illinois University at Carbondale (SIU-C), California Energy Commission (CEC), and T. R. Miles, Technical Consultants, Inc. In the UFP technology, coal and air are simultaneously converted into separate streams of (1) high-purity hydrogen that can be utilized in fuel cells or turbines, (2) sequestration-ready CO{sub 2}, and (3) high temperature/pressure vitiated air to produce electricity in a gas turbine. The process produces near-zero emissions and, based on ASPEN Plus process modeling, has an estimated process efficiency of 6 percentage points higher than IGCC with conventional CO{sub 2} separation. The current RD it also provides a summary of program activities and accomplishments covering progress in tasks including lab-scale experimental testing, pilot-scale testing, kinetic modeling, program management and technology transfer.

/pdf/fuel-flexible-gasification-combustion-technology-for-1z7uxnsw8x.pdf

Fuel-flexible gasification-combustion technology for production of h2 and sequestration-ready co2

Abstract Articular cartilage and meniscus injuries are prevalent disorders with insufficient regeneration responses offered by available treatment methods. In this regard, 3D bioprinting has emerged as one of the most promising new technologies, offering novel treatment options. Additionally, the latest achievements from the fields of biomaterials and tissue engineering research identified constituents facilitating the creation of biocompatible scaffolds. In this study, we looked closer at hyaluronic acid and multi-walled carbon nanotubes as bioink additives. Firstly, we assessed the minimal concentrations that stimulate cell viability, and decrease reactive oxygen species and apoptosis levels in 2D cell cultures of normal human knee articular chondrocytes (NHAC) and human adipose-derived mesenchymal stem cells (hMSC-AT). In this regard, 0.25 mg/ml of hyaluronic acid and 0.0625 mg/ml of carbon nanotubes were selected as the most optimal concentrations. In addition, we investigated the protective influence of 2-phospho-L-ascorbic acid in samples with carbon nanotubes. Tests conducted on 3D bioprinted constructs revealed that only a combination of components positively impacted cell viability throughout the whole experiment. Gene expression analysis of COL1A1 , COL6A1 , HIF1A , COMP , RUNX2, and POU5F1 showed significant changes in the expression of all analyzed genes with a progressive overall loss of transcriptional activity in most of them. 

/pdf/hyaluronic-acid-and-multiwalled-carbon-nanotubes-as-bioink-3ajmydwq.pdf

Tomasz Szymański

Papers

Effect of gas composition on the kinetics of iron oxide reduction in a hydrogen production process

Cycling effects on the methane regeneration kinetics of CuO/γ-Al2O3 sorbent

Fuel-flexible gasification-combustion technology for production of h2 and sequestration-ready co2

Hyaluronic acid and multiwalled carbon nanotubes as bioink additives for cartilage tissue engineering