Air Products (United States)

The accelerating global demand for clean energy has placed hydrogen as a pivotal vector for achieving carbon neutrality. However, over 95% of current hydrogen is still derived from fossil-based routes such as steam methane reforming (SMR), which remains energy-intensive and carbon-emitting. Chemical looping technology (CLT) has emerged as an innovative low-carbon pathway capable of inherently separating CO2 during hydrogen generation. This review systematically examines recent advances in methane-based CLT, emphasizing oxygen carrier (OC) design, process efficiency, and environmental implications. Across different CLT configurations, the technology shows excellent performance, with CH4 conversion above 95% and H2 purity reaching 99.9%. It also achieves 10–15% higher thermal efficiency than conventional SMR with carbon capture. Among key variants, CLPO produces syngas with a H2/CO ratio of ∼2, CLSR yields 90–95 vol % pure H2, and CLCHP achieves >97% CO2 capture with >90% OC regeneration sustained over 100 cycles. Meanwhile, CLMC enables theoretical 100% CH4 conversion at 1000 °C without CO2 emissions and produces valuable solid carbon. Environmentally, Fe2O3-based OCs outperform Ni- or Co-based counterparts due to low toxicity, thermal stability (750–950 °C), and a reduction in lifecycle emissions to 3009 g CO2-eq/kg H2. The review identifies research priorities for scalable deployment, including the development of durable OCs, system integration with waste heat or biomass, and reactor optimization capable of reducing capital costs by up to 37%.

Very high power adjustable speed motor applications above 15 MW historically used Load Commutated Inverter drives coupled to designed for purpose synchronous motors. These systems required detailed application engineering for the particular site to mitigate potential power factor, line harmonics, torque pulsation, and motor design requirements. In the past decade manufacturers have started offering Voltage Source Inverter PWM drives at these power levels, up to 13.8 kV motor voltage for both induction and synchronous motors, which have fewer application complications. These large drives were initially based on either 5-level Neutral Point Clamped or Cascaded H Bridge topologies, usually limited to 11 kV, but now some manufacturers are utilizing Modular Multilevel Converters for the very high power, applications with voltages above 11 kV. The Modular Multilevel Converter topology will be further explored together with its application to these medium voltage motors.

Copyright © 2020 by the Society of Critical Care Medicine and Wolters Kluwer Health, Inc. All Rights Reserved.

Implementing a hospital medication for addiction treatment (MAT) and a linkage program can improve care for patients with substance use disorder (SUD); however, lack of hospital funding and brick and mortar SUD resources are potential barriers to feasibility. This study assesses the feasibility of implementation of a SUD linkage program. Components of the program include a county-funded hospital opioid support team (HOST), a hospital-employed addiction recovery specialist (ARS), and a medical toxicology MAT induction service and maintenance program. Data for linkage by HOST, ARS, and MAT program were tracked from July 2018 to December 2019. From July 2018 through December 2019, 1834 patients were linked to treatment: 1536 by HOST and 298 by the ARS. The most common disposition categories for patients linked by HOST were 16.73% to medically monitored detoxification, 9.38% to intensive outpatient, and 8.59% to short-term residential treatment. Among patients linked by the ARS, 65.66% were linked to outpatient treatment and 9.43% were linked directly to inpatient treatment. A total of 223 patients managed by the ARS were started on MAT by medical toxicology and linked to outpatient MAT clinic: 72.68% on buprenorphine/naloxone, 24.59% on naltrexone, 1.09% buprenorphine, and 0.55% acamprosate. Implementing a MAT and linkage program in the ED and hospital setting was feasible. Leveraging medical toxicology expertise as well as community and funding partnerships was crucial to successful implementation.

Abstract Due to their excellent high temperature oxidation resistance, utilities worldwide are adopting advanced austenitic stainless steels (A-ASS) for critical plant components, such as heat exchangers, as they aim to achieve higher operating conditions. However, challenges may be encountered in developing life assessment and life management strategies for such components. This is because conventional methods used for life assessment, such as measuring steam side oxide scale thickness in ferritic and conventional austenitic material to predict tube metal temperature, may not be successfully applied to A-ASS. In such instances, tracking the formation and evolution of microstructural features during service, may offer a possible method to predict the temperature of these steels. For such metallurgy based lifing strategy to be successful, it is essential to develop a good understanding of microstructure evolution in these steels. In this work one heat of Super 304H, that has been creep tested at 600°C, 650°C and 700°C, with applied stress ranging from 110 to 340 MPa, is characterized using a combination of advanced characterization tools and image analysis methods. The amount of sigma phase formed at the gauge and grip sections of the samples is quantified and the methodology used to quantify this phase is presented. From the results, a time-temperature-transformation diagram for sigma formation is developed.

A PM made Cr-V ledeburitic tool steel Vanadis 6 has been subjected to conventional austenitizing and quenching, which was followed by sub-zero treatment at different temperatures, and by tempering treatments. The microstructure, hardness and fracture toughness of sub-zero treated steel have been investigated with reference to the same material after conventional room temperature quenching. The main findings are that sub-zero treatments reduce the retained austenite amount, enhance the population density of small carbides, refine the martensite and change the precipitation of carbides during tempering. These alterations are reflected in elevated hardness after low-temperature tempering but slightly lowered hardness after tempering within the normal secondary hardening temperature range, except the specimens treated at-140 °C where the hardness improvement was maintained. The fracture toughness is rather negatively influence by the sub-zero treatments, except the treatment at-140 °C where no impact or rather improvement has been recorded; thus, the treatment at a temperature of-140 °C seems to be a promising way how to improve the hardness and the fracture toughness pf the Vanadis 6 steel simultaneously.