Constructing well defined nanostructures is promising but still challenging for high‐efficiency catalysts for hydrogen evolution reaction (HER) and energy storage. Herein, utilizing the differences in surface energies between (111) facets of CoP and NiCoP, a novel CoP/NiCoP heterojunction is designed and synthesized with a nanotadpoles (NTs)‐like morphology via a solid‐state phase transformation strategy. By effective interface construction, the disorder in terms of electronic structure and coordination environment at the interface in CoP/NiCoP NTs is created, which leads to dramatically elevated HER performance within a wide pH range. Theoretical calculations prove that an optimized proton chemisorption and H2O dissociation are achieved by an optimized phosphide polymorph at the interface, accelerating the HER reaction. The CoP/NiCoP NTs are also proved to be excellent candidates for use in supercapacitors (SCs) with a high specific capacitance (1106.2 F g−1 at 1 A g−1) and good cycling stability (nearly 100% initial capacity retention after 1000 cycles). An asymmetric supercapacitor shows a high energy density (145 F g−1 at 1 A g−1) and good cycling stability (capacitance retention is 95% after 3200 cycles). This work provides new insights into the catalyst design for electrocatalytic and energy storage applications.

This paper reports the development of a thermal chemical vapor deposition process for pure cobalt from the source precursor cobalt tricarbonyl nitrosyl for incorporation in integrated circuit silicide applications. Studies were carried out to examine the underlying mechanisms that control Co nucleation and growth kinetics, including the effects of key process parameters on film purity, texture, morphology, and electrical properties. For this purpose, systematic variations were implemented for substrate temperature, precursor flow, hydrogen reactant flow, and deposition time (thickness). Resulting films were analyzed by Rutherford backscattering spectrometry, X-ray photoelectron spectroscopy, X-ray diffraction, fourpoint resistivity probe, scanning electron microscopy, and atomic force microscopy. These investigations identified an optimized process window for the growth of pure Co with resistivity of 9 + 2 µΩ cm, smooth surface morphology, and root-mean-square surface roughness at or below 10% of film thickness.

Cardiac engineering of patches and tissues is a promising option to restore infarcted hearts, by seeding cardiac cells onto scaffolds and nurturing their growth in vitro. However, current patches fail to fully imitate the hierarchically aligned structure in the natural myocardium, the fast electrotonic propagation, and the subsequent synchronized contractions. Here, superaligned carbon-nanotube sheets (SA-CNTs) are explored to culture cardiomyocytes, mimicking the aligned structure and electrical-impulse transmission behavior of the natural myocardium. The SA-CNTs not only induce an elongated and aligned cell morphology of cultured cardiomyocytes, but also provide efficient extracellular signal-transmission pathways required for regular and synchronous cell contractions. Furthermore, the SA-CNTs can reduce the beat-to-beat and cell-to-cell dispersion in repolarization of cultured cells, which is essential for a normal beating rhythm, and potentially reduce the occurrence of arrhythmias. Finally, SA-CNT-based flexible one-piece electrodes demonstrate a multipoint pacing function. These combined high properties make SA-CNTs promising in applications in cardiac resynchronization therapy in patients with heart failure and following myocardial infarctions.

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Despite the tremendous market penetration of smartphones, their utility has been and will remain severely limited by their battery life. A major source of smartphone battery drain is accessing the Internet over cellular or WiFi connection when running various apps and services. Despite much anecdotal evidence of smartphone users experiencing quicker battery drain in poor signal strength, there has been limited understanding of how often smartphone users experience poor signal strength and the quantitative impact of poor signal strength on the phone battery drain. The answers to such questions are essential for diagnosing and improving cellular network services and smartphone battery life and help to build more accurate online power models for smartphones, which are building blocks for energy profiling and optimization of smartphone apps. In this paper, we conduct the first measurement and modeling study of the impact of wireless signal strength on smartphone energy consumption. Our study makes four contributions. First, through analyzing traces collected on 3785 smartphones for at least one month, we show that poor signal strength of both 3G and WiFi is routinely experienced by smartphone users, both spatially and temporally. Second, we quantify the extra energy consumption on data transfer induced by poor wireless signal strength. Third, we develop a new power model for WiFi and 3G that incorporates the signal strength factor and significantly improves the modeling accuracy over the previous state of the art. Finally, we perform what-if analysis to quantify the potential energy savings from opportunistically delaying network traffic by exploring the dynamics of signal strength experienced by users.

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Background: Frailty, originally characterized in communitydwelling older adults, is increasingly being studied and implemented for adult patients with end-stage kidney disease (ESKD) of all ages (>18 years). Frailty prevalence and manifestation are unclear in younger adults (18-64 years) with ESKD; differences likely exist based on whether the patients are treated with hemodialysis (HD) or kidney transplantation (KT).

Articles you may be interested inChemically enhanced physical vapor deposition of tantalum nitride-based films for ultra-large-scale integrated devices J.Low temperature plasma-promoted chemical vapor deposition of tantalum from tantalum pentabromide for copper metallizationIn this article, the authors report the development of a new low temperature plasma-assisted chemical vapor deposition ͑PACVD͒ process for the growth of low resistivity, cubic tantalum nitride (TaN x ) for incorporation as a diffusion barrier/adhesion promoter in emerging ultralarge-scale integrated ͑ULSI͒ multilevel metallization ͑MLM͒ schemes. TaN x films were produced in a low density plasma using tantalum pentabromide, hydrogen, and nitrogen as coreactants. The films were grown at substrate temperatures of 350-450°C, reactor working pressures of 0.9-1.6 Torr, hydrogen flow rates between 250 and 1500 sccm, nitrogen flow rates of 100-600 sccm, and plasma power ranging from 10 to 60 W, corresponding to a power density of 0.06-0.33 W/cm 2 . The films were subsequently characterized by Auger electron spectroscopy, Rutherford backscattering spectrometry, x-ray diffraction, atomic force microscopy, four-point resistivity probe, and cross-sectional scanning electron microscopy. These studies indicated that the TaN x films produced were stoichiometric and carbon and oxygen free, contained bromine concentrations below 3 at. %, and exhibited resistivities as low as 150 ⍀ cm. The conformality was higher than 95% in the nominally 0.3 m, 4.5:1 aspect ratio structures. These results indicate that in the case of halide-based Ta chemistries, PACVD in a (N 2 ϩH 2 ) plasma might be more viable than thermal CVD in a NH 3 atmosphere for the deposition of TaN x for ULSI MLM applications.