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Organic field‐effect transistors (OFETs) have shown great promise for use as chemical sensors for applications that range from the monitoring of food spoilage to the determination of air quality and the diagnosis of disease. However, for these devices to be truly useful, they must deliver reliable and stable low‐voltage operation over extended timescales. An important element to address this challenge is the development of a high‐capacitance gate dielectric that delivers excellent insulation with robust chemical resistance against the solution processing of organic semiconductors (OSC). The development of a bilayer gate dielectric containing a high‐k fluoropolymer relaxor ferroelectric layer modified at the OSC/dielectric interface with a photo‐crosslinked chemically resistant low‐k methacrylate‐based copolymer buffer layer is reported. Bottom‐gate OFET chemical sensors using this bilayer dielectric operate at low‐voltage with exceptional operational stability. They deliver reliable sensing performance over multiple cycles of ammonia exposure (2 to 50 ppm) with an estimated limit‐of‐detection below 1 ppm.

Flexible supercapacitors, a state-of-the-art material, have emerged with the potential to enable major advances in for cutting-edge electronic applications. Flexible supercapacitors are governed by the fundamentals standard for the conventional capacitors but provide high flexibility, high charge storage and low resistance of electro active materials to achieve high capacitance performance. Conducting polymers (CPs) are among the most potential pseudocapacitor materials for the foundation of flexible supercapacitors, motivating the existing energy storage devices toward the future advanced flexible electronic applications due to their high redox active-specific capacitance and inherent elastic polymeric nature. This review focuses on different types of CPs-based supercapacitor, the relevant fabrication methods and designing concepts. It describes recent developments and remaining challenges in this field, and its impact on the future direction of flexible supercapacitor materials and relevant device fabrications.

Summary 1. The xylem pressure inducing 50% loss of hydraulic conductivity due to embolism (P50 ) is widely used for comparisons of xylem vulnerability among species and across aridity gradients. However, despite its utility as an index of resistance to catastrophic xylem failure under extreme drought, P5o may have no special physiological relevance in the context of stomatal regulation of daily minimum xylem pressure and avoidance of hydraulic failure under non-extreme conditions. Moreover, few studies of hydraulic architecture have accounted for the buffering influence of tissue hydraulic capacitance on daily fluctuations in xylem pressure in intact plants. 2. We used data from 104 coniferous and angiosperm species representing a range of woody growth forms and habitat types to evaluate trends in three alternative xylem hydraulic safety margins based on features of their stem xylem vulnerability curves and regulation of daily minimum stem water potential (Y stem min ) under non-extreme conditions: (i)Ystem min - P50, (ii) Y stem min - Pe, the difference between Ystem min and the threshold xylem pressure at which loss of conductivity begins to increase rapidly (Pe) and (iii) Pe - P50 an estimate of the steepness of the vulnerability curve between Pe and P50. Additionally, we assessed relationships between xylem capacitance, species-specific set-points for daily minimum stem water potential and hydraulic safety margins in a subset of species for which relevant data were available. 3. The three types of hydraulic safety margin defined increased with decreasing species-specific set-points for Y stem min, suggesting a diminishing role of stem capacitance in slowing fluctuations in xylem pressure as Ystem min became more negative. The trends in hydraulic safety were similar among coniferous and angiosperm species native to diverse habitat types. 4. Our results suggest that here is a continuum of relative reliance on different mechanisms that confer hydraulic safety under dynamic conditions. Species with low capacitance and denser wood experience greater daily maximum xylem tension and appear to rely primarily on xylem structural features to avoid embolism, whereas in species with high capacitance and low wood density avoidance of embolism appears to be achieved primarily via reliance on transient release of stored water to constrain transpiration-induced fluctuations in xylem tension.

The first objective of the present study was to quantify the effects of tree age and stem position on specific conductivity ( k s ), vulnerability to embolism and water storage capacity (capacitance) in trunks of young, mature and old-growth ponderosa pine. The second objective was to determine relationships between hydraulic characteristics and radial and height growth rates to increase the understanding of possible tradeoffs. Within sapwood at all heights and in all ages of trees, outer sapwood had 25‐60% higher k s than inner sapwood. The water potential at which embolism started (air entry point) was 1.3 MPa lower in inner sapwood than outer sapwood within the mature trees, but there was no difference in the other trees. There was no significant difference in capacitances between the tops of the old growth trees, the mature trees and the young trees. Taking all data together, the capacitances increased sharply with an increase in k s and an increase in vulnerability to embolism. The hydraulic characteristics of the three age classes were correlated with the height growth rate but not with the diameter growth rate. Within these age classes, high k s was associated with the slowest yearly increase in sapwood area and with a low percentage of latewood, whereas high vulnerability to embolism and high capacitance were more closely associated with high height growth rates.

We investigated a-IGZO TFT with ZrO2 gate-dielectric having high on-current. High-capacitance is necessary to lead high on-current. Among many candidates, ZrO2 which is one of the most promising high-k materials has high capacitance originated high dielectric constant. We fabricated a-IGZO TFTs with ZrO2 gate-dielectric and analyzed electrical performances. Especially much higher mobility of 26 cm2/Vs and on-current of ∼6 mA than reported in other previous work are obtained. Also the threshold voltage (Vth), the on-to-off current ratio and the subthreshold swing are obtained of 3.6 V, of 9.6 × 106 and 0.6 V/decade, respectively.

— 8-in. AC plasma display panels with front address (FA) structures were developed. Deep barrier ribs, high-Xe-content gas, and long sustain gaps were applied to FA structures to achieve high luminous efficacy. The FA structures have several advantages over conventional structures. Because address electrodes are closer to sustain electrodes, FA PDPs can be driven at lower address voltages, under the condition of deep barrier ribs or high-Xe-content gas, than conventional PDPs. A disadvantage of FA PDPs is relatively high capacitance between the sustain electrodes and address electrodes compared to that of conventional PDPs.

We report on a low cost flat panel display technology in which high contrast inorganic electroluminescent devices using GaN phosphors and high capacitance thick dielectrics are formed on display glass substrates. This GaN electroluminescent technology combines a simple device structure with low cost fabrication processes.