Low-Pressure Deuterium Storage on Palladium-Coated Titanium Nanofilms: A Versatile Model System for Tritium-Based Betavoltaic Battery Applications.

Deuterium (D2(g)) storage of Pd-coated Ti ultra-thin films at relatively low pressures is fine-tuned by systematically controlling the thicknesses of the catalytic Pd overlayer, underlying Ti ultra-thin film domain, D2(g) pressure (PD2), duration of D2(g) exposure, and the thin film temperature. Structural properties of the Ti/Pd nanofilms are investigated via XRD, XPS, AFM, SEM, and TPD to explore new structure-functionality relationships. Ti/Pd thin film systems are deuterated to obtain a D/Ti ratio of up to 1.53 forming crystallographically ordered titanium deuteride (TiDx) phases with strong Tix+-Dy- electronic interactions and high thermal stability, where >90% of the stored D resides in the Ti component, thermally desorbing at >460 °C in the form of D2(g). Electronic interaction between Pd and D is weak, yielding metallic (Pd0) states where D storage occurs mostly on the Pd film surface (i.e., without forming ordered bulk PdDx phases) leading to the thermal desorption of primarily DOH(g) and D2O(g) at <265 °C. D-storage typically increases with increasing Ti film thickness, PD2, T, and t, whereas D-storage is found to be sensitive to the thickness and the surface roughness of the catalytic Pd overlayer. Optimum Pd film thickness is determined to be 10 nm providing sufficient surface coverage for adequate wetting of the underlying Ti film while offering an appropriate number of surface defects (roughness) for D immobilization and a relatively short transport pathlength for efficient D diffusion from Pd to Ti. The currently used D-storage optimization strategy is also extended to a realistic tritium-based betavoltaic battery (BVB) device producing promising ß-particle emission yields of 164 mCi/cm2, an open circuit potential (VOC) of 2.04 V, and a short circuit current (ISC) of 7.2 nA.

Nitriding Effect on the Tribological Performance of CrN-, AlTiN-, and CrN/AlTiN-Coated DIN 1.2367 Hot Work Tool Steel.

In this study, heat-treated and multisurface engineered DIN 1.2367 tool steel was subjected to room and elevated temperature wear tests, and the effect of nitriding on its tribological behavior was investigated. CrN, AlTiN, and CrN/AlTiN coatings with a total thickness of 2 µm were obtained by arc cathodic physical vapor deposition on conventional heat-treated and gas-nitrided steels. The white layer formed during nitriding was removed, and a diffusion layer (100 µm) was achieved in the cross section of the steel having a tempered martensitic matrix. The highest surface hardness was attained with an integral coating (CrN/AlTiN), and surface hardness increased even more after nitriding due to the formation of a multicomponent ceramic layer on top of the diffusion layer. The room temperature wear tests performed against an alumina counterpart revealed that (i) CrN/AlTiN-coated steel had the highest friction coefficient of 0.26, which further increased to 0.33 by nitriding due to the increase in shear strength, and that (ii) with increasing surface hardness, the specific wear rates (W) of the heat-treated and coated steels could be ranked as follows: WCrN/AlTiN < WAlTiN < WCrN. The wear rates decreased when nitriding was carried out prior to coating. In order to simulate the aluminum extrusion conditions, hot wear behavior of the surfaces against AA6080 alloy at 450 °C was investigated. The hot wear tests revealed that (i) high friction coefficients were reached due to the adhesive characteristic of aluminum to the surfaces, (ii) the nitrided and CrN/AlTiN-coated sample exhibited the lowest wear rate among all studied surfaces, and (iii) the film damage on the worn surfaces mostly occurred in the form of droplet delamination.

Digital Leadership's Influence on Individual Creativity and Employee Performance: A View through the Generational Lens.

Today's digitalized business atmosphere places significant emphasis on digital leadership, as digital transformation can only be successful for leaders who are capable of overseeing the entire digitalization process. In this study, we examine the employee-level outputs of digital leadership in terms of individual creativity and employee performance. Based on the data of 348 employees and by using PLS-SEM, we find that (i) digital leadership is a significant antecedent of individual creativity, and (ii) individual creativity fully mediates the relationship between digital leadership and employee performance. When digital leadership abilities are a matter of concern, it becomes necessary to mention the importance of generational differences between those leaders, as OB studies also underline the generational differences toward new technologies. Hence, we also conducted a multigroup analysis (MGA) to determine if those interrelationships among digital leadership, individual creativity, and employee performance differ due to the generations of the managers. Surprisingly, the MGA results reveal minor differences. The findings of this study highlight the importance of embracing digital leadership in fostering a creative and high-performing work environment and provide insights for organizations aiming to harness the unique strengths and talents of their multigenerational workforce. Digital leaders who foster a culture of innovation, adaptability, and open communication can inspire employees to think creatively and come up with novel ideas. By leveraging digital tools and providing a supportive environment, digital leaders can also enhance employee creativity and performance.

Differential in vitro inhibition studies of some cerium vanadate derivatives on xanthine oxidase.

In this preliminary study, a new series of some cerium vanadate derivatives have been investigated as new type of inhibitors of xanthine oxidase (XO; E.C 1.17.3.2). XO is a superoxide-producing enzyme found normally in serum and the lungs, and its activity is concerned with several important health problems such as gout, severe liver damage, vascular dysfunction and injury, oxidative eye injury and renal failure. In this study, we present a critical overview of the effects of these novel type agents on XO with comparing the efficacy and safety profiles of allopurinol, the efficient classical inhibitor of XO.

4-Functionalized 1,3-diarylpyrazoles bearing benzenesulfonamide moiety as selective potent inhibitors of the tumor associated carbonic anhydrase isoforms IX and XII.

A library of 4-functionalized 1,3-diarylpyrazoles (3a-3h, 5a-5g and 6a-6g) was designed, synthesized and evaluated against four human carbonic anhydrase (CA, EC 4.2.1.1) isozymes representing two cytosolic isozymes hCA I and hCA II, and two transmembrane tumor associated ones, hCA IX and hCA XII. All the twenty two tested compounds exhibited excellent CA activity profile against the four CA isozymes when compared to the reference drug acetazolamide. Six of the tested compounds (3a-3b, 3f, 3h, 6a and 6b) displayed low nanomolar affinity (Ki < 5 nM) for hCA IX whereas seven compounds (3a-3b, 3d-3f, 3h and 6f) displayed Ki < 10 nM against hCA XII. In addition, they acted as selective CA inhibitors of isoforms IX and XII over the physiological isoforms I and II.

Benzenesulfonamide bearing 1,2,4-triazole scaffolds as potent inhibitors of tumor associated carbonic anhydrase isoforms hCA IX and hCA XII.

Three series of novel heterocyclic compounds (3a-3g, 4a-4g and 5a-5g) containing benzenesulfonamide moiety and incorporating a 1,2,4-triazole ring, have been synthesized and investigated as inhibitors against four isomers of the α-class carbonic anhydrases (CAs, EC 4.2.1.1), comprising hCAs I and II (cytosolic, ubiquitous isozymes) and hCAs IX and XII (transmembrane, tumor associated isozymes). Against the human isozymes hCA I and II, compounds of two series (3a-3g and 4a-4g) showed Ki values in the range of 84-868 nM and 5.6-390 nM, respectively whereas compounds of series 5a-5g were found to be poor inhibitors (Ki values exceeding 10,000 nM in some cases). Against hCA IX and XII, all the tested compounds exhibited excellent to moderate inhibitory potential with Ki values in the range of 2.8-431 nM and 1.3-63 nM, respectively. Compounds 3d, 3f and 4f exhibited excellent inhibitory potential against all of the four isozymes hCA I, II, IX and XII, even better than the standard drug acetazolamide (AZA) whereas compound of the series 5a-5g were comparatively less potent but more selective towards hCA IX and XII.

Salen and tetrahydrosalen derivatives act as effective inhibitors of the tumor-associated carbonic anhydrase XII--a new scaffold for designing isoform-selective inhibitors.

Salen and tetrahydrosalen derivatives possess metal-chelating properties and have been used as ligands in organic synthesis and as scaffolds for developing therapeutic agents. Fourteen such compounds were synthesized in order to explore their ability to inhibit the zinc enzyme carbonic anhydrase (CA, EC 4.2.1.1). Human (h) isoforms hCA I, hCA II, hCA IX and hCA XII were included in the investigation. Several aliphatic and aromatic spacers were introduced between the two chelating groups from salen/tetrahydrosalen in order to explore a diverse chemical space for designing CA inhibitors, which incorporate both phenol and polyamine fragments in their molecule. Some of these compounds showed CA inhibitory activity in the low micromolar-nanomolar range and a pronounced selectivity for inhibiting an isoform over-expressed in hypoxic tumors, hCA XII, over hCA I, II and IX.