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Decades of research on solute-induced phase transformation of metal hydride systems have shown the possibility to enhance hydrogen storage properties through novel material design such as nanoconfinement engineering. Nevertheless, the fundamentals of mechanical stress effect on confined Pd nanoparticles remain yet to be elucidated due to the difficulty in linking with hydrogen sorption thermodynamics. Here, a thermodynamic tuning of Pd nanocubes associated with hydrogen sorption as a result of encapsulation by reduced graphene oxide (rGO) layers is demonstrated. Pd nanocubes are constrained by rGO to such a degree that the chemical potential and the pressure hysteresis of the system during hydrogen sorption drastically change while showing a size dependence. A thorough thermodynamic analysis elucidates the role of constraints on hydrogen uptake and release; despite the nanoscale regime, the thermodynamic parameters (enthalpy and entropy) during phase transition considerably increase, a phenomenon not seen before in unconstrained Pd nanoparticle systems.

This study reports a miniaturised discontinuous conduction mode (DCM) variable on-time (VOT) buck converter providing an output of 1.8 V in the input range of 3–12 V to support applications with large wireless coupling. Conventionally, an additional large capacitor has been used as a bootstrap capacitor to drive the high-side switch of buck converters, which prevents minimisation. In this study, a standalone momentary power consumption level shifter is proposed to remove the additional bootstrap capacitor and increase the power conversion efficiency (PCE) in the buck converter. A Zener diode is utilised to reduce the power consumption of the level shifter. In addition, a dead-time-based off-time calibration circuit is proposed to further increase the PCE by reducing the low-side conduction loss. The proposed circuit is fabricated with a TSMC 0.18-µm BCD process, and the core circuit occupies an active area of 0.68 mm2 with two external components. It provides output currents in the range of 20 µA to 3 mA with a maximum switching frequency of 750 kHz. The maximum efficiency of the converter below 5 mW is 80.2%.

This paper presents a fingerprint mutual capacitive touchscreen panel (TSP) readout IC, which uses a differential coded multiple signaling (DCMS) method. A readout IC with high SNR and fast frame rate is required for fingerprint recognition. However, achieving high SNR is challenging owing to the limited capacitance difference originating from the small depth variations between the ridges and valleys of the fingerprint. In addition, scanning the entire fingerprint TSP with multiple electrodes is time-consuming. A fully differential receiver with DCMS is proposed to detect the low capacitance difference in a fingerprint TSP. The internal noise is minimized by the low-noise amplifier, and external noise is eliminated by a lock-in sensing architecture. In addition, DCMS reduces the offset and enhances the SNR while achieving faster frame rate in multiple channels. The proposed architecture can detect capacitance of 50 aF, which is the capacitance difference resulting from the ridges and valleys of a finger under a 0.3-mm-thick (T) cover glass. The readout IC achieves 15.1-dB peak-to-peak SNR and 23-Hz frame rate with a transparent mutual capacitive fingerprint TSP under 0.3T glass. The power consumption is below 21 mW at 3.3-V supply voltage. The IC was fabricated using a 0.18- $ {\mu }\text{m}$ standard CMOS process.

An instantaneous power consuming level shifter is presented in this brief to increase the dc converter efficiency. The level shifter is used in a high-side power switch driver to remove the external capacitor which is used in bootstrap technique. The level shifter consumes power only during the transition period. A delay cell is used to turn the level shifter off to reduce the power consumption period. An output voltage detector is added to turn the level shifter off even before the delay time. An asynchronous discontinuous conduction mode buck converter is designed to verify the performance of the level shifter. Simulation results show that the power consumption of the proposed level shifter decreased by 66%, while the converter efficiency increased by the maximum of 9% compared to results obtained for a conventional level shifter. The converter is fabricated using the TSMC 0.18- $\boldsymbol {\mu }\text{m}$ BCD process and it operates within an input range of 2–5 V when the current varies from 400 $\boldsymbol {\mu }\text{A}$ to 18 mA and delivers an output voltage of 1.8 V.

Graphene was chosen as an additive to improve the hydrogen uptake and release properties of magnesium (Mg). Five weight percent of graphene was added to Mg or pre-milled Mg by milling in hydrogen (reactive milling). The milling processes and hydrogen uptake and release properties of the graphene-added Mg were investigated. Adding graphene to Mg and then milling the mixture of Mg and graphene in hydrogen for 6 h [named M5G (6 h)] had little effects on the improvement of hydrogen uptake and release properties of Mg. Pre-milling of Mg (for 24 h) and then adding 5 wt.% of graphene by milling in hydrogen (for 30 min) (named M5G) significantly increased the hydrogen uptake and release rates and the quantities of hydrogen absorbed and released for 60 min of Mg. The activation of M5G was completed after cycle number, CN, of two (CN = 2). M5G had a high effective hydrogen-storage capacity of 6.21 wt.% at 623 K in 12 bar H2 at CN = 3. M5G released 0.25 wt.% hydrogen for 2.5 min and 5.28 wt.% hydrogen for 60 min H2 in 1.0 bar H2 at 623 K at CN = 3. Pre-milling of Mg and then adding graphene by milling in hydrogen and hydrogen uptake-release cycling are believed to create defects, produce cracks and clean surfaces, and decrease particle sizes. DOI: http://dx.doi.org/10.5755/j01.ms.25.3.20567

In this paper, a fully integrated active rectifier with triple feedback loops is proposed to enhance power conversion efficiency (PCE) over a wide loading range by calibrating both the gate transition timing and power switch size. The on- and off-transitions of the power switches are calibrated using a hybrid delay-based gate control circuit (HDGCC) with hybrid feedback loops. Conventional active rectifiers that only focused on calibrating the gate transition timing of a NMOS power switch with a fixed power switch size exhibit a low PCE when the loading condition deviates from the predetermined range. Thus, an automatic size selector based on a third feedback loop is proposed, which changes the power switch size based on the loading condition and ensures a stable operation of the hybrid loops by maintaining the voltage drop across the NMOS switches. An active rectifier was fabricated using the standard 0.18 μm CMOS process. The effectiveness and robustness of the two-dimensional calibration were verified through measurements under an AC input voltage ranging from 2.5 to 5.0 V and an output power ranging from 1.25 to 125 mW. The peak voltage conversion ratio and peak PCE were 97.6% and 95.0%, respectively, at RL = 500 Ω.

Background: Emerging evidence suggests that intestinal dysbiosis contributes to systemic inflammation and cardiovascular diseases in dialysis patients. The purpose of this study was to evaluate the effects of probiotic supplementation on various inflammatory parameters in hemodialysis (HD) patients.Methods: Twenty-two patients with maintenance HD were enrolled. These patients were treated twice a day with 2.0 ×1010 colony forming units of a combination of Bifidobacterium bifidum BGN4 and Bifidobacterium longum BORI for 3 months. The microbiome and fecal short-chain fatty acids (SCFAs) were analyzed. The percentages of CD14+ CD16+ proinflammatory monocytes and CD4+ CD25+ regulatory T-cells (Tregs) before and after probiotic supplementation were determined by flow cytometry. Serum levels of calprotectin and cytokine responses upon lipopolysaccharide (LPS) challenge were compared before and after probiotic supplementation.Results: Fecal SCFAs increased significantly after probiotic supplementation. Serum levels of calprotectin and interleukin 6 upon LPS stimulation significantly decreased. The anti-inflammatory effects of probiotics were associated with a significant increase in the percentage of CD4+ CD25+ Tregs (3.5% vs. 8.6%, p < 0.05) and also with a decrease of CD14+ CD16+ proinflammatory monocytes (310/mm2 vs. 194/mm2, p < 0.05). Conclusion: Probiotic supplementation reduced systemic inflammatory responses in HD patients and this effect was associated with an increase in Tregs and a decrease in proinflammatory monocytes. Hence, targeting intestinal dysbiosis might be a novel strategy for decreasing inflammation and cardiovascular risks in HD patients.

This paper presents a photovoltaic(PV) energy-harvesting system with fast maximum power point tracking (FMPPT) circuit that utilizes 4-bit successive approximation register analog to digital converter (SAR ADC) suitable for solar cells. Solar Panel’s output power depends on switch duty ratio of inductive-boost DC/DC converter. Usability of 4-bit/cycle SAR ADC to adjust duty ratio is proved through the measurement, using conventional Pulse Frequency Modulation (PFM) boost converter. This circuit achieves short tracking time of 4-cycle in order to reach the MPP and high MPPT efficiency of 99.5 %, while consuming the low power. The switches and control stages were implemented into 0.18 -um CMOS process, and a chip size is 2.13 x 1.66 mm2.

To improve the hydrogen uptake and release properties of magnesium (Mg), five weight percent of graphene was added to pre-milled Mg by milling in hydrogen (reaction-involving milling). The hydrogen uptake and release properties of the graphene-added Mg (named Mg-5graphene) were investigated. Premilling of Mg (for 24 h) and then adding graphene by milling in hydrogen (for 30 min) significantly increased the hydrogen uptake and release rates and the quantities of hydrogen absorbed and released for 60 min of the Mg and graphene composite. The activation of Mg-5graphene was completed after the second hydrogen uptake-release cycle (n=2). Mg-5graphene had a high effective hydrogen-storage capacity (quantity of hydrogen absorbed for 60 min) of 5.47 wt% at 593 K in 12 bar H2 at n=3. Mg-5graphene absorbed 0.92 wt% H for 2.5 min, 2.67 wt% H for 10 min, and 5.62 wt% H for 60 min in 12 bar H2 and released 0.25 wt% H for 2.5 min and 4.99 wt% H for 60 min in 1.0 bar H2 at 623 K at n=1. The increase in ID/IG, the ratio of intensities of D and G peaks in Raman spectra, after reaction-involving milling of the pre-milled Mg with graphene, compared with that of the used graphene, suggests that defects and disordering in the graphene were increased. We believe that the generation of stacking fault disorder and formation of turbostratic graphite occurred after milling with the pre-milled Mg, rather than the formation of defects, in graphene. (Received April 30, 2018; Accepted June 8, 2018)

Graphene (multilayer graphene) was chosen as an additive to improve the hydrogen uptake and release properties of magnesium (Mg). Five weight percent of graphene was added to pre-milled Mg by milling in hydrogen (reaction-involving milling). The hydrogen uptake and release properties of the graphene-added Mg were investigated. The activation of Mg-5graphene, which was prepared by adding 5 wt% graphene to Mg pre-milled for 24 h, was completed after the second cycle (cycle number, CN = 2). Mg-5graphene had a high effective hydrogen-storage capacity (the quantity of hydrogen absorbed for 60 min) of 6.21 wt% at CN = 3 at 593 K in 12 bar H2. At CN = 1, Mg-5graphene released 0.46 wt% hydrogen for 10 min and 4.99 wt% hydrogen for 60 min. Milling in hydrogen is believed to create defects (leading to facilitation of nucleation), produce cracks and clean surfaces (leading to increase in reactivity), and decrease particle size (leading to diminution of diffusion distances or increasing the flux of diffusing hydrogen atoms). The added graphene is believed to have helped the sample have higher hydrogen uptake and release rates, weakly but partly, by dispersing heat rapidly.

Magnesium (Mg) has good hydrogen storage features except for its slow reaction kinetics with hydrogen and high hydride decomposition temperature. Yttria (Y2O3)-stabilized zirconia (ZrO2) (YSZ), nickel (Ni), and graphene were picked as additives to Mg to solve these problems. Samples with a composition of 92.5 wt% Mg + 2.5 wt% YSZ + 2.5 wt% Ni + 2.5 wt% graphene (designated as Mg + YSZ + Ni + graphene) were prepared by grinding in hydrogen atmosphere. The activation of Mg + YSZ + Ni + graphene was finished at the third cycle (n = 3). Mg + YSZ + Ni + graphene had an efficient hydrogen storage capacity (the amount of hydrogen absorbed for 60 min) over 7 wt% (7.11 wt%) at n = 1. Mg + YSZ + Ni + graphene contained Mg2Ni phase after cycling. The addition of Ni and Ni + YSZ greatly increased the initial hydride formation and decomposition rates, and the amount of hydrogen absorbed and released for 60 min, Ha (60 min) and Hd (60 min), respectively, of a 95 wt% Mg + 5 wt% graphene sample (Mg + graphene). Rapid nucleation of the Mg2Ni-H solid solution in Ni-containing samples is believed to have led to higher initial decomposition rates than Mg + graphene and Mg. The addition of YSZ also enhanced the initial decomposition rate and Hd (60 min) compared to a sample with a composition of 95 wt% Mg + 2.5 wt% Ni + 2.5 wt% graphene (Mg + Ni + graphene).

〈100〉 axes of the rod-shaped grains of laser irradiated cold-rolled 3.04%-Si steel sheets are parallel to either solidification direction or normal direction of the steel sheet. The portion of desirable textures was enhanced by controlling of atmosphere and the direction of heat flow. The area fraction of the texture, which has 〈100〉 axis parallel to normal direction of the steel sheet, in the laser-affected steel sheets in air and argon atmosphere increased up to 23.4% and 26.3%, respectively, compared to a conventionally annealed steel sheet (8.2%).

This paper presents a fingerprint mutual capacitive touch-screen panel (TSP) readout IC (ROIC) with a differential signaling method for fast fingerprint recognition. A readout IC with high SNR and fast frame rate are required in the fingerprint recognition. However, the capacitance difference by the ridge and valley of the fingerprint is very small, so that the signal-to-noise ratio is very low. In addition, it takes long time to scan whole fingerprint TSP with multiple electrodes. A fully differential architecture with differential signaling is proposed to detect the low capacitance difference in fingerprint TSP. The internal noise generated is minimized by 2nd fully differential operational amplifier and external noise is eliminated by a lock-in sensing structure. In addition, DCMS reduces an AC offset and enhances a higher product of SNR and frame rate in multiple channels. Proposed IC has been fabricated using a 0.18 μm standard CMOS process.

This paper describes an atto farad capacitive sensing system for a finger-print sensor. The architecture of mutual capacitive finger-print sensor is obtained by investigating the capacitance change by the finger-print based on the Q3D Extractor model. An electrostatic simulation shows that the 200aF difference caused by the valley and the ridge in the sensor. In order to sense the atto farad capacitance in finger-print sensor, a continuous-type fully differential architecture with a differential transmitted signals is proposed to amplify a capacitance difference only with a reduced the parasitic effect caused by a large number of electrodes. The prototype IC with 0.18um CMOS achieves 300mV/200aF.