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Not AvailableHigh-entropy diboride ceramics are promising for ultra-high-temperature applications. However, their oxidation mechanisms and kinetics require further investigation. This study reports a hydrogen-assisted microwave plasma (HAMP) synthesis route for high-entropy diboride, (Hf0.2Mo0.2Ta0.2Ti0.2Zr0.2)B2 from metal-oxide precursors. Atomic hydrogen generated in the microwave plasma promotes efficient reduction of the metal oxide precursors, enabling direct synthesis of a single-phase AlB2-type high-entropy diboride. Further densification by spark plasma sintering resulted in ∼95% relative density while maintaining a uniform elemental distribution. Oxidation behavior was investigated up to 1300°C using thermogravimetric analysis under continuous heating. The diboride exhibits continuous mass gain across oxidation ranges, attributed to development of a composite oxide scale. Kinetic analysis shows temperature-dependent shifts in oxidation mechanisms, supported by phase and microstructural characterization. Despite containing oxidation-sensitive elements, the diboride exhibits oxidation resistance comparable to HfB2. These findings highlight the role of multicomponent interactions and hydrogen-assisted plasma chemistry on oxidation behavior in high-entropy diborides. 

This work focused on optimization of dysprosium orthoferrite (DFO) nanofiller loading (3, 6, 9, 12 and 15 wt%) into PVDF matrix through various structural and electrical characterizations. The flexible composite films were synthesized using doctor blade technique. The improved electroactive phase content leads to enhanced dielectric, energy storage properties and mechanical energy harvesting performance in DFO reinforced PVDF composites. The storage density and efficiency are found to be excellent for 6 wt% loading (DFP6) i.e. 19.39 J/cm3 at 200 kV/ cm and 76 % respectively. DFP6 flexible nanogenerator device was able to generate maximum open circuit voltage of 21.44 ± 0.93 V and power density of 6.74 ± 0.42 μW/cm2 under the mechanical stimuli with constant pressure 4.2 kPa and periodic tapping of 16 Hz. DFP6 generates 9.72, 4.91, 6.27 and 1.1 V corresponding to index, middle finger tapping, heel pressing, and adult coughing, respectively. The waterdrop from 40 cm height able to produce ~510 mV suggesting its potentiality for rainwater harvesting to electrical energy. The voltage response of the bath and probe sonication indicates its potentiality for underwater application. The device exhibits excellent durability with no performance degradation over 8 months and stability over 5000 cycles. 

Abstract Surface segregation is a ubiquitous phenomenon driven by minimization of the total free energy. In this paper we study surface segregation in multicomponent magnetic Bismuth ferrite nanoparticles alloyed with varying amounts of Dysprosium, Zinc and Titanium. We employ surface and bulk sensitive spectroscopic probes to unravel a significant surface segregation of Bismuth oxide and Titanium oxide. High coercive fields of BiFe_0.95Ti_0.05O₃(BFTO) and BiFe_0.96(Zn, Ti)_0.02O₃(BFZTO) at room temperature reveal that they have a strong exchange bias. This suggests that the Titanium oxide is magnetically active, and there is a Ti inducedd^oferromagnetism in action between these nanoparticles. We show, with the addition of Dy₂O₃, the Ti inducedd^oferromagnetism is suppressed making (BDFZTO) superparamagnetic. We observe that all three differently alloyed Bismuth ferrite nanoparticles show a non-saturating paramagnetic background. 

This paper addresses the critical challenge of sustaining research innovation and productivity during periods of instability in federal funding by examining long-term U.S. research funding trends and behaviors. It is original in its integrated analysis of federal, industry, state, and philanthropic funding dynamics as a unified strategy for institutional resilience. The study employed a scholarly and policy literature review combined with secondary data analysis. It synthesized historical U.S. research funding trends using data from the National Center for Science and Engineering Statistics (NCSES). The analysis incorporated quantitative funding metrics and qualitative assessments across federal, industry, state, and philanthropic sectors to evaluate shifts in research investment patterns and ecosystem behavior. The findings demonstrate that while federal funding has historically underpinned the U.S. research enterprise, it is increasingly unstable and complemented by growing industry dominance and strategic philanthropic investment. Importantly, the study shows that research expenditures remain relatively stable despite federal budget fluctuations due to lag effects, institutional buffering, and diversified funding streams. This study is essential in assisting researchers and research administrators with understanding how to maintain research innovation and productivity during unstable periods of government funding by providing historic research funding trends and funding behaviors.  Additionally, this review contributes to the field by: providing a systems-level framework for understanding multi-sector research funding dynamics; demonstrating the resilience mechanisms within the U.S. research ecosystem; reframing funding diversification as a strategic necessity rather than an option; offering evidence-based insight into how funding shifts toward applied and translational research are reshaping institutional strategies. 

High-entropy alloys (HEAs) are a class of multi-element materials that exhibit unique structural and functional properties. This study reports on the synthesis and characterization of a superconducting HEA, (NbTa)0.55(HfTiZr)0.45 fabricated using the vacuum arc melting technique. Scanning electron microscopy and energy-dispersive x-ray spectroscopy were employed to analyze the material's morphology and composition. X-ray diffraction analysis revealed a single-phase body-centered cubic (BCC) structure with a measured nanoindentation hardness of 6.4 GPa and Young's modulus of 132 GPa. This HEA superconductor was investigated by x-ray diffraction at Beamline 13BM-C, Advanced Photon Source, and the BCC phase was stable to the highest pressure of 50 GPa. Superconductivity was characterized by four-probe resistivity measurements in a quantum design physical property measurement system, yielding a superconducting transition temperature (Tc) of 7.2 K at ambient pressure and reaching a maximum of 10.1 K at the highest applied pressure of 23.6 GPa. The combination of high structural stability enhanced superconducting performance under pressure and superior mechanical properties highlights (NbTa)0.55(HfTiZr)0.45 as a promising superconductor under extreme environments. 

Abstract This study compares the growth cycles and spatial distribution of dust cloud for titania and carbonaceous dusty nanoparticles in capacitively coupled radiofrequency plasmas, with and without the presence of a weak magnetic field of approximately 500 Gauss. Findings on cycle time, growth rate, and spatial distribution of dust cloud are discussed. The growth of nanoparticles in these plasmas is cyclic, with particles reaching their maximum size and subsequently moving out of the plasma, followed by the generation of a new particle growth cycle. The presence of the magnetic field speeds up the growth cycle in both plasma. The magnetic field also makes the spatial distribution of the two dust cloud different from each other. Langmuir probe measurement of the background plasma parameters such as electron temperature and floating potential reveal radial variations in floating potential but not electron temperature. Furthermore, the magnetic field changes the radial variation of floating potential. These measurements, however, are not sufficient to explain why the two dust clouds appear differently. It is possible that the differences occur due to a gradient in the radial distribution of the magnetic field.