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Biofilms, are significant component that contributes to the development of chronic infections, especially when medical devices are involved. This issue offers a huge challenge for the medical community since standard antibiotics are only capable of eradicating biofilms to a very limited degree. The prevention of biofilm formation have led to the development of a variety of coating methods and new materials. These methods are intended to coat surfaces in such a way as to inhibit the formation of biofilm. Metallic glassy alloys, in particular, alloys that include copper and titanium metals have gained popularity as desirable antibacterial coating. Meanwhile, there has been a rise in the use of the cold spray coating technique due to the fact that it is a proper approach for processing temperature-sensitive materials. The present study was carried out in part with the intention of developing a new antibiofilm metallic glassy consisting of ternary Cu-Zr-Ni using mechanical alloying technique. The spherical powders that comprised the end-product were utilized as feedstock materials for cold spray coatings to stainless steel surfaces at low temperature. When compared to stainless steel, substrates coated with metallic glassy were able to significantly reduce the formation of biofilm by at least one log., (© 2022. The Author(s).)

Antibacterial agents derived from conventional organic compounds have traditionally been employed as a biofilm protective coating for many years. These agents, on the other hand, often include toxic components that are potentially hazardous to humans. Multiple approaches have been investigated over the last two decades, including the use of various metallic and oxide materials, in order to produce a diverse variety of usable coating layers. When it comes to material coating approaches, the cold spray technique, which is a solid-state method that works well with nanopowders, has shown superior performance. Its capacity to produce unique material coating in ways that are not possible with other thermal methods is the primary reason for its importance in contemporary production. The present work has been addressed in part to explore the possibility of employing mechanically alloyed Cu 50 (Ti 50-x Ni x ) x ; x = 10, 20, 30, and 40 at.% metallic glass powders, for producing an antibiofilm/SUS304 surface protective coating, using the cold spray approach. In this study, elemental Cu, Ti, and Ni powders were low-energy ball milled for 100 h to fabricate metallic glassy powders with different Ni contents. The as-prepared metallic glassy powders were utilized to coat SUS304 sheets, using the cold spraying process. With high nanohardness values, the as-fabricated coating material, in particular Cu 50 Ti 20 Ni 30, demonstrated remarkable performance in comparison to other materials in its class. Furthermore, it displayed excellent wear resistance while maintaining a low coefficient of friction, with values ranging from 0.32 to 0.45 in the tested range. E. coli biofilms were formed on 20 mm 2 SUS304 sheet coated coupons, which had been injected with 1.5 108 CFU mL -1 of the bacterium. With the use of nanocrystalline Cu-based powders, it is feasible to achieve considerable biofilm inhibition, which is a practical strategy for accomplishing the suppression of biofilm formation.

Glasses, which date back to about 2500 BC, originated in Mesopotamia and were later brought to Egypt in approximately 1450 BC. In contrast to the long-range order materials (crystalline materials), the atoms and molecules of glasses, which are noncrystalline materials (short-range order) are not organized in a definite lattice pattern. Metallic glassy materials with amorphous structure, which are rather new members of the advanced materials family, were discovered in 1960. Due to their amorphous structure, metallic glassy alloys, particularly in the supercooled liquid region, behave differently when compared with crystalline alloys. They reveal unique and unusual mechanical, physical, and chemical characteristics that make them desirable materials for many advanced applications. Although metallic glasses can be produced using different techniques, many of these methods cannot be utilized to produce amorphous alloys when the system has high-melting temperature alloys (above 1500 °C) and/or is immiscible. As a result, such constraints may limit the ability to fabricate high-thermal stable metallic glassy families. The purpose of this research is to fabricate metallic glassy (Zr 70 Ni 25 Al 5 ) 100-x W x (x; 0, 2, 10, 20, and 35 at. %) by cold rolling the constituent powders and then mechanically alloying them in a high-energy ball mill. The as-prepared metallic glassy powders demonstrated high-thermal stability and glass forming ability, as evidenced by a broad supercooled liquid region and a high crystallization temperature. The glassy powders were then consolidated into full-dense bulk metallic glasses using a spark plasma sintering technique. This consolidation method did not result in the crystallization of the materials, as the consolidated buttons retained their short-range order fashion. Additionally, the current work demonstrated the capability of fabricating very large bulk metallic glassy buttons with diameters ranging from 20 to 50 mm. The results indicated that the microhardness of the synthesized metallic glassy alloys increased as the W concentration increased. As far as the authors are aware, this is the first time this metallic glassy system has been reported.

Background: Primary immune deficiency (PID) patients may develop acute or chronic pain. Pain has not been studied in this population until now., Objectives: This study systematically assessed the pain of various durations in PID patients using validated pain questionnaires., Subjects and Methods: A Short-Form McGill Pain Questionnaire (SF-MPQ), already validated in the Arabic language, was used to ascertain the characteristics and severity of pain. Additionally, an Arabic version of the Neuropathic Pain Questionnaire-Short Form (NPQ-SF) was employed to evaluate neuropathic pain in the same group of patients., Results: Forty-six patients participated in the study. The mean age of the patients was 25 years. The most commonly diagnosed PID was a common variable immune deficiency (32.6%), followed by severe combined immune deficiency (19.57%). Based on the SF-MPQ, the pain was experienced by 30.4 % of the subjects who participated in the study; 57% of whom were on regular pain medications. The most common site reported for pain was the abdomen (35.7%). The mean duration of pain was 36.1 days ± 34.6 days. The most common comorbidities in these patients were bronchiectasis, followed by immune thrombocytopenic purpura, and scoliosis. None of the PID patients had significant neuropathic pain based on NFQ-SF., Conclusion: To the best of our knowledge, this is the first study to assess the prevalence as well as the severity and duration of pain in PID patients. There were significantly more subjects who had continuous pain. Treatment of pain in PID patients will have a significant effect on improving their quality of life., Competing Interests: There are no conflicts of interest., (Copyright: © 2021 Saudi Journal of Anaesthesia.)

Throughout human history, any society's capacity to fabricate and refine new materials to satisfy its demands has resulted in advances to its performance and worldwide standing. Life in the twenty-first century cannot be predicated on tiny groupings of materials; rather, it must be predicated on huge families of novel elements dubbed "advanced materials". While there are several approaches and strategies for fabricating advanced materials, mechanical milling (MM) and mechanochemistry have garnered much interest and consideration as novel ways for synthesizing a diverse range of new materials that cannot be synthesized by conventional means. Equilibrium, nonequilibrium, and nanocomposite materials can be easily obtained by MM. This review article has been addressed in part to present a brief history of ball milling's application in the manufacture of a diverse variety of complex and innovative materials during the last 50 years. Furthermore, the mechanism of the MM process will be discussed, as well as the factors affecting the milling process. Typical examples of some systems developed at the Nanotechnology and Applications Program of the Kuwait Institute for Scientific Research during the last five years will be presented in this articles. Nanodiamonds, nanocrystalline hard materials (e.g., WC), metal-matrix and ceramic matrix nanocomposites, and nanocrystalline titanium nitride will be presented and discussed. The authors hope that the article will benefit readers and act as a primer for engineers and researchers beginning on material production projects using mechanical milling.

Hydrogen has been receiving great attention as an energy carrier for potential green energy applications. Hydrogen storage is one of the most crucial factors controlling the hydrogen economy and its future applications. Amongst the several options of hydrogen storage, light metal hydrides, particularly nanocrystalline magnesium hydride (MgH 2 ), possess attractive properties, making them desired hydrogen storage materials. The present study aimed to improve the hydrogen storage properties of MgH 2 upon doping with different concentrations of zirconium carbide (ZrC) nanopowders. Both MgH 2 and ZrC were prepared using reactive ball milling and high-energy ball milling techniques, respectively. The as-prepared MgH 2 powder was doped with ZrC (2, 5, and 7 wt%) and then high-energy-ball-milled for 25 h. During the ball milling process, ZrC powders acted as micro-milling media to reduce the MgH 2 particle size to a minimal value that could not be obtained without ZrC. The as-milled nanocomposite MgH 2 /ZrC powders consisted of fine particles (~0.25 μm) with a nanosized grain structure of less than 7 nm. Besides, the ZrC agent led to the lowering of the decomposition temperature of MgH 2 to 287 °C and the reduction in its apparent activation energy of desorption to 69 kJ/mol. Moreover, the hydrogenation/dehydrogenation kinetics of the nanocomposite MgH 2 /ZrC system revealed a significant improvement, as indicated by the low temperature and short time required to achieve successful uptake and release processes. This system possessed a high capability to tackle a long continuous cycle lifetime (1400 h) at low temperatures (225 °C) without showing serious degradation in its storage capacity.

Magnesium hydride (MgH 2 ) has received significant attention due to its potential applications as solid-state hydrogen storage media for useful fuel cell applications. Even though MgH 2 possesses several attractive hydrogen storage properties, it cannot be utilized in fuel cell applications due to its high thermal stability and poor hydrogen uptake/release kinetics. High-energy ball milling, and mechanically-induced cold-rolling processes are the most common techniques to introduce severe plastic deformation and lattice imperfection in the Mg/MgH 2 . Furthermore, using one or more catalytic agents is considered a practical solution to improve both the de-/rehydrogenation process of MgH 2 .These treatments are usually dedicated to enhance its hydrogen storage properties and deduce its thermal stability. However, catalyzation of Mg/MgH 2 powders with a desired catalytic agent using ball milling process has shown some disadvantages due to the uncontrolled distribution of the agent particles in the MgH 2 powder matrix. The present study has been undertaken to employ a cold gas-dynamic spray process for catalyzing the fresh surfaces of mechanically-induced cold-rolled Mg ribbons with Ni powder particles. The starting Mg-rods were firstly heat treated and forged 200 times before cold rolling for 300 passes. The as-treated ribbons were then catalyzed by Ni particles, using cold gas-dynamic spray process. In this catalyzation approach, the Ni particles were carried by a stream of Ar gas via a high-velocity jet at a supersonic velocity. Accordingly, the pelted Ni particles penetrated the Mg-substrate ribbons, and hence created numerous micropores into the Mg, allowed the Ni particles to form a homogeneous network of catalytic active sites in Mg substrate. As the number of coating time increased to three times, the Ni concentration increased (5.28 wt.%), and this led to significant enhancement of the Mg-hydrogen storage capacity, as well as improving the de-/rehydrogenation kinetics. This is evidenced by the high value of hydrogen storage capacity (6.1 wt.% hydrogen) and the fast gas uptake kinetics (5.1 min) under moderate pressure (10 bar) and temperature (200 °C). The fabricated nanocomposite MgH 2 /5.28 wt.% Ni strips have shown good dehydrogenation behavior, indicated by their capability to desorb 6.1 wt.% of hydrogen gas within 11 min at 200 °C under 200 mbar of hydrogen pressure. Moreover, this system possessed long cycle-life-time, which extended to 350 h with a minimal degradation in the storage and kinetics behavior.

Hydrogen, which is a new clean energy option for future energy systems possesses pioneering characteristics making it a desirable carbon-free energy carrier. Hydrogen storage plays a crucial role in initiating a hydrogen economy. Due to its low density, the storage of hydrogen in the gaseous and liquids states had several technical and economic challenges. Despite these traditional approaches, magnesium hydride (MgH 2 ), which has high gravimetric and volumetric hydrogen density, offers an excellent potential option for utilizing hydrogen in automobiles and other electrical systems. In contrast to its attractive properties, MgH 2 should be mechanically and chemically treated to reduce its high activation energy and enhance its modest hydrogen sorption/desorption kinetics. The present study aims to investigate the influence of doping mechanically-treated Mg metal with 5 wt% amorphous Zr 2 Cu abrasive nanopowders in improving its kinetics and cyclability behaviors. For the first time, solid-waste Mg, Zr, and Cu metals were utilized for preparing MgH 2 and amorphous Zr 2 Cu alloy (catalytic agent), using hydrogen gas-reactive ball milling, and arc melting techniques, respectively. This new nanocomposite system revealed high-capacity hydrogen storage (6.6 wt%) with superior kinetics and extraordinary long cycle-life-time (1100 h) at 250 °C.

A new solid-state hydrogen storage system of magnesium hydride (MgH 2 ) doped with 5 wt% of metallic glassy (MG) zirconium palladium (Zr 2 Pd) nanopowder was fabricated using a high-energy ball milling technique. The end-product obtained after 50 h of milling was consolidated into bulk buttons, using a hot-pressing technique at 350 °C. The results have shown that this consolidation step, followed by the repetitive pressing at ambient temperature did not affect the nanocrystalline characteristics of pressed powders. Recycling pressing demonstrated beneficial effects of plastic deformation and lattice imperfections on Mg, leading to its enhanced hydrogenation/dehydrogenation kinetics and cycle-life-time performance compared with untreated samples. The results elucidated that spherical, hard, nanopowder of MG-Zr 2 Pd were forced to penetrate the Mg/MgH 2 matrix to create micro/nanopore structures upon pressing for 50 cycles. These ultrafine spherical metallic glassy particles (∼400 nm in diameter) acted as a micro-milling media for reducing the particle size of MgH 2 powders into submicron particles. In addition, they played a vital role as grain growth inhibitors to prevent the undesired growth of Mg grains upon the application of a moderate temperature in the range of 50 °C to 350 °C. The apparent activation energy for the decomposition of this new consolidated nanocomposite material was measured to be 92.2 kJ mol -1 , which is far below than the measured value of pure nanocrystalline MgH 2 powders (151.2 kJ mol -1 ) prepared in the present study. This new binary system possessed superior hydrogenation kinetics, indicated by the rather low temperature (200 °C) required to uptake 6.08 wt% H 2 within 7.5 min. More importantly, the system revealed excellent dehydrogenation kinetics at 225 °C as implied by the limited time needed to release 6.1 wt% H 2 in 10 min. The MgH 2 /5 wt% MG-Zr 2 Pd system showed a high performance for cyclability, implied by the achievement of continuous cycles (338 cycles) at 225 °C without degradation over 227 h., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The present study aimed to enhance the kinetics behavior and destabilize the thermal stability of MgH 2 powder by high-energy milling of Mg powder under 50 bar of H 2 for several hours using Ti-balls as the milling media. The results showed a monotonical increase in Ti content worn off the milling media and introduced into the milled powders. This gradual doping led to homogeneous distribution of fine Ti particles into the Mg/MgH 2 powder matrix without agglomeration or compositional fluctuations at the micro-level. During the activation stage of the powders, achieved at 350 °C/35 bar H 2 prior to hydrogenation kinetics measurements, elemental Ti reacted with H 2 to form fine TiH 2 particles. Our proposed in situ mechanically induced catalyzation approach was found to be mutually beneficial for decreasing the apparent activation energy of decomposition. In addition, introducing 5.3 wt% of TiH 2 to the MgH 2 powder obtained after 50 h led to the achievement of superior enhancement of gas uptake/release kinetics at relatively low temperatures. The nanocomposite MgH 2 /5.3 TiH 2 powder possessed fast hydrogenation/dehydrogenation kinetics behaviors and revealed long cycle lifetimes. This system was successfully employed as a solid-state hydrogen source to charge the battery of a cell-phone device using an integrated Ti-tank/commercial proton exchange membrane-fuel cell system., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Formation of a new metastable fcc-MgH 2 nanocrystalline phase upon mechanically-induced plastic deformation of MgH 2 powders is reported. Our results have shown that cold rolling of mechanically reacted MgH 2 powders for 200 passes introduced severe plastic deformation of the powders and led to formation of micro-lathes consisting of γ- and β-MgH 2 phases. The cold rolled powders were subjected to different types of defects, exemplified by dislocations, stacking faults, and twinning upon high-energy ball milling. Long term ball milling (50 hours) destabilized β-MgH 2 (the most stable phase) and γ-MgH 2 (the metastable phase), leading to the formation of a new phase of face centered cubic structure (fcc). The lattice parameter of fcc-MgH 2 phase was calculated and found to be 0.4436 nm. This discovered phase possessed high hydrogen storage capacity (6.6 wt%) and revealed excellent desorption kinetics (7 min) at 275 °C. We also demonstrated a cyclic-phase-transformation conducted between these three phases upon changing the ball milling time to 200 hours., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)