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This review consolidates the evidence supporting endogenous HNO generation through enzymatic and non‐enzymatic pathways, emphasizing advancements in real‐time HNO sensing within living systems. Azanone (nitroxyl, HNO) is the one‐electron‐reduced congener of nitric oxide (NO•) and shares various biological actions. HNO exhibits unique properties, including positive inotropic and lusitropic effects, along with resistance to scavenging by reactive oxygen species (ROS), particularly superoxide. Research on HNO has intensified over the last two decades, focusing on its reactivity and the prospect of endogenous formation due to its potential significance. The high reactivity of HNO arises from reactions with biologically relevant species such as oxygen, NO•, and thiols, as well as self‐dimerization. Detecting and quantifying HNO has posed challenges, initially relying on nitrous oxide (N2O) detection, a byproduct of dimerization. Recent advancements, including fluorescent probes and a specific electrochemical nanomolar‐level sensor, have facilitated direct detection, enhancing understanding of HNO reactivity and formation. [ABSTRACT FROM AUTHOR]

Switching elements are crucial components in electrical and electronic systems that undergo severe degradation due to the electrical arc that is generated during breaking. Understanding the behavior of the electrical arc and modifying its characteristics via proper electrode design can significantly improve durability while also promoting optimal performance, reliability, and safety in circuit breakers. This work evaluates the feasibility of carbon nanotube (CNT)-reinforced silver and copper metal matrix composites (MMCs) as switching electrodes and the influence of CNT concentration on the characteristics of the arcs generated. Accordingly, three different concentrations per MMC were manufactured via powder metallurgy. The MMCs and reference materials were subjected to a single break operation and the electrical arcs generated using 100 W and 200 W resistive loads were analyzed. The proposed MMCs displayed promising results for application in low-voltage switches. The addition of CNTs improved performance by maintaining the arc's energy in the silver MMCs and reducing the arc's energy in the copper MMCs. Moreover, a CNT concentration of at least 2 wt.% is required to prevent unstable arcs in both metallic matrices. Increased CNT content further promotes the splitting of the electrical arc due to a more complex phase distribution, thereby reducing the arc's spatial energy density. [ABSTRACT FROM AUTHOR]

The piezoresistive effect of materials can be adopted for a plethora of sensing applications, including force sensors, structural health monitoring, motion detection in fabrics and wearable, etc. Although metals are the most widely adopted material for sensors due to their reliability and affordability, they are significantly affected by temperature. This work examines the piezoresistive performance of carbon nanoparticle (CNP) bulk powders and discusses their potential applications based on strain-induced changes in their resistance and displacement. The experimental results are correlated with the characteristics of the nanoparticles, namely, dimensionality and structure. This report comprehensively characterizes the piezoresistive behavior of carbon black (CB), onion-like carbon (OLC), carbon nanohorns (CNH), carbon nanotubes (CNT), dispersed carbon nanotubes (CNT-D), graphite flakes (GF), and graphene nanoplatelets (GNP). The characterization includes assessment of the ohmic range, load-dependent electrical resistance and displacement tracking, a modified gauge factor for bulk powders, and morphological evaluation of the CNP. Two-dimensional nanostructures exhibit promising results for low loads due to their constant compression-to-displacement relationship. Additionally, GF could also be used for high load applications. OLC’s compression-to-displacement relationship fluctuates, however, for high load it tends to stabilize. CNH could be applicable for both low and high loading conditions since its compression-to-displacement relationship fluctuates in the mid-load range. CB and CNT show the most promising results, as demonstrated by their linear load-resistance curves (logarithmic scale) and constant compression-to-displacement relationship. The dispersion process for CNT is unnecessary, as smaller agglomerates cause fluctuations in their compression-to-displacement relationship with negligible influence on its electrical performance. [ABSTRACT FROM AUTHOR]

The article titled "Update on Endogenous HNO Production: An Exploration of Unanswered Questions and Challenges" in the European Journal of Inorganic Chemistry discusses the biological function of HNO and its generation in living organisms. The article presents various mechanistic proposals for the production of HNO, categorized as enzymatic or non-enzymatic. The importance of HNO in medicine, particularly in cardiovascular health, is highlighted, emphasizing its potential. Additionally, the article mentions that HNO levels in plant leaf cells can vary in response to developmental processes and environmental factors. The full details can be found in the review by P. Vargas, F. A. Doctorovich, and S. A. Suarez. [Extracted from the article]