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Recently, aqueous Zn-ion rechargeable batteries have drawn increasing research attention as an alternative energy storage system relative to the current Li-ion batteries due to their intrinsic properties of high safety, low cost, and high theoretical volumetric capacity. Nevertheless, unwanted dendrite growth on the Zn anode and unstable cathode materials restrict their practical application. In this study, a unique 2D MoS2 coating on a Zn anode using an electrochemical deposition method has been developed for preventing dendrite growth and intricate side reactions. The coated MoS2 layer is a vertically oriented structure that makes the flow of Zn ions easy with a uniform electric field distribution on the anode, resulting in a uniform stripping and plating of Zn2+. In addition, the MoS2 coating enhances anodic diffusion of Zn ions and reduces the series resistance as confirmed by EIS analysis and therefore improves the overall battery performance. The full cell assembled with the MoS2-Zn anode and MnO2 cathode exhibits an excellent reversible specific capacity of 638 mAh/g at 0.1 A/g and stable cycle performance over 2000 cycles with no dendrite formation at the Zn electrode. The presented MoS2 coating on Zn is a facile, scalable, and promising technology for practical Zn-ion batteries with a long life cycle and high safety.

In this work, we prepared spinel-type NiCo2O4 (NCO) nanopowders as a low-cost and sensitive electrochemical sensor for nonenzymatic glucose detection. A facile and simple chemical bath method to synthesize the NCO nanopowders is demonstrated. The effect of pH and annealing temperature on the formation mechanism of NCO nanoparticles was systematically investigated. Our studies show that different pHs of the precursor solution during synthesis result in different intermediate phases and relating chemical reactions for the formation of NCO nanoparticles. Different morphologies of the NCO depending on pHs are also discussed based on the mechanism of growth. Electrochemical performance of the prepared NCO was characterized towards glucose, which reveals that sensitivity and selectivity of the NCO are significantly related with the final microstructure combined with constituent species with multiple oxidation states in the spinel structure.

Recently, aqueous Zn-ion rechargeable batteries have drawn increasing research attention as an alternative energy storage system relative to the current Li-ion batteries due to their intrinsic properties of high safety, low cost, and high theoretical volumetric capacity. Nevertheless, unwanted dendrite growth on the Zn anode and unstable cathode materials restrict their practical application. In this study, a unique 2D MoS

Recent technological progress towards the application of wearable electronic devices has prompted the development of flexible electrodes. To date, various technical approaches to improve the mechanical and electrical reliability of flexible electrodes have been reported; however, the transition from lab-scale processing to industrialization is still limited by complex processing steps involved in their preparation. Simple engineering steps are introduced to prepare flexible electrodes fabricated from silver-polydimethylsiloxane (Ag-PDMS) composites for wearable device applications. The electrical properties of the electrodes were investigated under stretching and bending conditions. Also, the effect of different Ag contents in the electrodes on electrical properties was investigated. As increasing the Ag content above 300 wt.%, Ag-PDMS electrodes exhibit electrical conductivity, which is closely related to the percolation threshold for the formation of a 3-D network of Ag in the PDMS matrix. Further increase of Ag content up to 450 wt.% resulted in electrical conductivity about 1000 S/cm, corresponding to an electrical resistivity of 1 mΩ cm. Furthermore, we investigated the electrical resistivity changes when repetitive stretching and bending deformation was applied. Based on the conceptual demonstration of a light-emitting diode circuit using Ag-PDMS electrodes, a simple printable electrode fabrication method can be applied to various stretchable electronic devices.

Sr substituted BaTiO 3 (BST) nanopowders were prepared using oxalate co-precipitation methods. During synthesis, oxygen was applied to the oxalate solution in order to control the oxidation states of Ti. Control of pH in the solution results in different crystalline phases of the powders after calcination; pure perovskite BST was obtained in the powder prepared at pH 3 solution, while perovskite BaTiO 3 (BTO) and impurities were observed in powders prepared at pH 1 solution. Phase transformation from amorphous to crystalline BST during heat treatment was discussed by different analysis technique. Also, morphology and elemental distribution of the pure BST was investigated.

The reliability of negative temperature coefficient (NTC) thermistors is one of the important factors for the excellent performance of the battery management system in electric vehicles. The electrical properties of the thermistor can be explained by the indirect electron jump between Mn3+ and Mn4+ at the B-sites in a spinel-type thermistor. Additionally, different types of dopants, such as Fe, Cu, Zn, Cr, and Mn, are considered as electrical modifiers that can further improve the electrical properties of the thermistor. For example, Cu is often added to NTC thermistors, occupying the octahedral sites in a spinel-type thermistor, which can play an important role in conduction with the Mn cations. Addition of Fe is also widely used in NTC thermistors owing to its high sensitivity, B constant, and stability. In this study, composition-dependent structural and electrical properties of Cu0.2/Fey-co-doped Ni0.3Mna-x-yCo0.9O4 (NMC) are investigated. Cu/Fe-co-doped NMC shows the R25 and B25/85 constant values of 4490–12730 Ω and 3185–3490 K, respectively, exhibiting a typical ρ–T curve of NTC thermistors. Higher B constant and reliable electrical stability are observed for Cu/Fe-co-doped NMC. Based on the relationship between the cationic oxidation states and electrical properties of Cu/Fe-co-doped NMC, the hopping conduction mechanism is discussed.

Development of a cost-effective oxygen evolution reaction (OER) catalyst for hydrogen production from water has attracted the attention of scientists due to its potential to solve current environmental and energy issues, such as CO2 emissions and depletion of fossil fuels. In this paper, we report a facile synthesis to develop cobalt-manganese-oxide (MnxCo3−xO4, CMO) nanorods via an oxalate precipitation method followed by annealing at different temperatures. Importantly, morphology and surface area of the CMO nanorods, which are directly related to the OER activity, can be precisely controlled by changing annealing temperatures. The CMO nanorods engineered by oxalate precipitation and subsequent heat treatment show promising OER catalytic performance, such as a small overpotential of 365 mV for generating a current density of 10 mA cm−2, a low Tafel slope of 50.6 mV dec−1, and excellent long-term stability in alkaline media. Electrochemical properties combined with materials characterization provide insightful information on the OER mechanism of the CMO nanorods.

High-performance oxygen evolution reaction (OER) electrocatalysts are needed to produce hydrogen for energy generation through a carbon-free route. In this work, the solution combustion synthesis (SCS) method was employed to synthesize mixed phases of Co- and Mn-based oxides, and the relationships between the crystalline structure and the catalytic properties in the mixed phases were established. The mixed phases of Co- and Mn-based oxides shows promising OER properties, such as acceptable overpotential (450 mV for 10 mA∙cm&minus, 2) and Tafel slope (35.8 mV∙dec&minus, 1), highlighting the use of the mixed phases of Co- and Mn-based oxides as a new efficient catalysts for water splitting. Electronic structure of the mixed phases of Co- and Mn based oxides is studied in detail to give insight for the origin of high catalytic activities. In addition, excellent long-term stability for OER in alkaline media is achieved for the mixed phase of Co- and Mn based oxides.

To understand relationship between hump degradation and FN stress, we have investigated FN stress induced damage process in this paper. We have found that sub-threshold hump increase could be caused by edge hole trap along the STI/Si interface. The surprising degradation of double-hump is observed depending on the bias-temperature stress. The FN stress induced transistor hump makes the off leakage current (Ioff) and degradation of memory device performance

PEGylation has been considered to be a good biotechnique for improving the therapeutic value of glucagon-like peptide-1 (GLP-1) analogs for the treatment of type 2 diabetes. Despite the attractive anti-diabetic potentials, GLP-1 does not exert its full biological action because of its extremely short life-time in vivo due to rapid proteolytic degradation. Here, the enzyme-resistant mono-PEGylated GLP-1 isomers substituted at Lys(26)- or Lys(34)-amine were prepared through a newly devised site-specific PEGylation process using a maleic anhydride-protection/deprotection method. The therapeutic potentials of these site-specific PEGylated GLP-1 isomers (Lys(26)- or Lys(34)-PEG-GLP-1) along with His(7)-(N-terminus) PEG-GLP-1 were evaluated by examining their insulinotropic activity, glucose-stabilizing capability, and proteolytic stability. Lys(34)-PEG-GLP-1 was found to have the well-preserved insulinotropic activity (93% efficacy versus GLP-1) in isolated rat pancreatic islets. Furthermore, Lys(34)-PEG-GLP-1 showed the most prominent glucose-stabilizing capability, evaluated via an oral glucose tolerance test in db/db mice by considering the following three crucial factors: (i) maximum blood glucose level (BGL), (ii) required time to lower the BGL below 100mg/dl, and (iii) total hypoglycemic degree. Additionally, Lys(34)-PEG-GLP-1 had longer half-lives than the other PEGylated GLP-1s in the dipeptidyl peptidase IV (DPP IV) inhibitor-treated liver or kidney homogenate, and its stability against DPP IV was also comparable to that of Lys(26)-PEG-GLP-1. Taken together, Lys(34)-PEG-GLP-1 displayed the promising characteristics in all evaluations versus His(7)- or Lys(26)-PEG-GLP-1. This site-specific PEGylated GLP-1 analog would have therapeutic usefulness for treating type 2 diabetes on account of the well-preserved insulinotropic activity, the increased proteolytic stability, and thereby the improved glucose-stabilizing capability.

We have observed new charge trapping phenomena in sub-80-nm DRAM recessed- channel-array-transistor (RCAT) after Fowler-Nordheim (FN) stress. Gate stack process strongly affected the charge trapping and the trap generating in oxide bulk and interface of RCAT. According to the trapped charges and/or the generated traps after FN stress, the data retention time and writing capabilities of DRAM were dramatically changed. We have summarized the electrical characteristics of RCAT fabricated with different gate stack processes.

An exact lifetime extrapolation models of ZrO2-Al2O3-ZrO2 (ZAZ) stack capacitor with metal-insulator-metal (MIM) structure was studied in this paper. From the extensive long-term test result (~ 7.5 months) it was found that the power-law model is suitable as a exact lifetime extrapolation model for ZAZ dielectric reliability.

Background:It has been well recognized that exercise tolerance and angina threshold in patients with coronary artery disease (CAD) are reduced after a meal. But precise mechanism leading to the postprandial worsening of angina has yet to be adequately defined. This study was undertaken to determine the effect of a mixed meal on cardiac performance and heart rate variability (HRV) in patients with CAD. Methods:24 patients with angina or myocardial infarction were studied. Echocardiographic examination and heart rate variability test were performed in the fasting state and the other 40-60 minutes after a 600–800 kcal mixed meal. Results:In the postprandial state, resting heart rate was significantly increased by 5.2% from 64.8±10.69 beats/min to 68.2±10.2 beats/min (p

Background:Ventricular function is one of the important prognostic factors in patients with coronary artery disease. Among noninvasive approaches for the evaluation of ventricular performance, radionuclide ventr- iculography has shown to be of particular values in the patients with myocardial infarction. We have evaluated ventricular function with ECG-gated blood pool scan (GBPS in patients with myocardial infarction of different locations and compared right and left ventricular functions. Method:Left and right ventricular function was assessed with multigated blood pool scan in 49 patients at 2-3 weeks after acute myocardial infarction (anterior infarction=23, inferior infarction=19, and lateral infarction=7. Left ventricular ejection fraction (LVEF, right ventricular ejection fraction (RVEF, maximal emptying rate, maximal filling rate, phase angle and full width at half maximum (FWHM of phase angles were measured during rest. Results: 1 LVEF was significantly lower in the patients with anterior myocardial infarction (32.2% than that of inferior (46.5%, p