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101.
Silvia Nappini Danil W. Boukhvalov Gianluca D'Olimpio Libo Zhang Barun Ghosh Chia‐Nung Kuo Haoshan Zhu Jia Cheng Michele Nardone Luca Ottaviano Debashis Mondal Raju Edla Jun Fuji Chin Shan Lue Ivana Vobornik Jory A. Yarmoff Amit Agarwal Lin Wang Lixue Zhang Federica Bondino Antonio Politano 《Advanced functional materials》2020,30(22)
By means of theory and experiments, the application capability of nickel ditelluride (NiTe2) transition‐metal dichalcogenide in catalysis and nanoelectronics is assessed. The Te surface termination forms a TeO2 skin in an oxygen environment. In ambient atmosphere, passivation is achieved in less than 30 min with the TeO2 skin having a thickness of about 7 Å. NiTe2 shows outstanding tolerance to CO exposure and stability in water environment, with subsequent good performance in both hydrogen and oxygen evolution reactions. NiTe2‐based devices consistently demonstrate superb ambient stability over a timescale as long as one month. Specifically, NiTe2 has been implemented in a device that exhibits both superior performance and environmental stability at frequencies above 40 GHz, with possible applications as a receiver beyond the cutoff frequency of a nanotransistor. 相似文献
102.
Jiayi Yang David Tang Jinping Ao Tushar Ghosh Taylor V. Neumann Dongguang Zhang Egor Piskarev Tingting Yu Vi Khanh Truong Kai Xie Ying‐Chih Lai Yang Li Michael D. Dickey 《Advanced functional materials》2020,30(36)
Soft, capacitive tactile (pressure) sensors are important for applications including human–machine interfaces, soft robots, and electronic skins. Such capacitors consist of two electrodes separated by a soft dielectric. Pressing the capacitor brings the electrodes closer together and thereby increases capacitance. Thus, sensitivity to a given force is maximized by using dielectric materials that are soft and have a high dielectric constant, yet such properties are often in conflict with each other. Here, a liquid metal elastomer foam (LMEF) is introduced that is extremely soft (elastic modulus 7.8 kPa), highly compressible (70% strain), and has a high permittivity. Compressing the LMEF displaces the air in the foam structure, increasing the permittivity over a large range (5.6–11.7). This is called “positive piezopermittivity.” Interestingly, it is discovered that the permittivity of such materials decreases (“negative piezopermittivity”) when compressed to large strain due to the geometric deformation of the liquid metal droplets. This mechanism is theoretically confirmed via electromagnetic theory, and finite element simulation. Using these materials, a soft tactile sensor with high sensitivity, high initial capacitance, and large capacitance change is demonstrated. In addition, a tactile sensor powered wirelessly (from 3 m away) with high power conversion efficiency (84%) is demonstrated. 相似文献
103.
Eduardo Lupi Anirban Ghosh Sahar Saremi Shang‐Lin Hsu Shishir Pandya Gabriel Velarde Abel Fernandez Ramamoorthy Ramesh Lane W. Martin 《Advanced Electronic Materials》2020,6(3)
The ability to produce atomically precise, artificial oxide heterostructures allows for the possibility of producing exotic phases and enhanced susceptibilities not found in parent materials. Typical ferroelectric materials either exhibit large saturation polarization away from a phase boundary or large dielectric susceptibility near a phase boundary. Both large ferroelectric polarization and dielectric permittivity are attained wherein fully epitaxial (PbZr0.8Ti0.2O3)n/(PbZr0.4Ti0.6O3)2n (n = 2, 4, 6, 8, 16 unit cells) superlattices are produced such that the overall film chemistry is at the morphotropic phase boundary, but constitutive layers are not. Long‐ (n ≥ 6) and short‐period (n = 2) superlattices reveal large ferroelectric saturation polarization (Ps = 64 µC cm−2) and small dielectric permittivity (εr ≈ 400 at 10 kHz). Intermediate‐period (n = 4) superlattices, however, exhibit both large ferroelectric saturation polarization (Ps = 64 µC cm−2) and dielectric permittivity (εr = 776 at 10 kHz). First‐order reversal curve analysis reveals the presence of switching distributions for each parent layer and a third, interfacial layer wherein superlattice periodicity modulates the volume fraction of each switching distribution and thus the overall material response. This reveals that deterministic creation of artificial superlattices is an effective pathway for designing materials with enhanced responses to applied bias. 相似文献
104.
Brian Elder Rajan Neupane Eric Tokita Udayan Ghosh Samuel Hales Yong Lin Kong 《Advanced materials (Deerfield Beach, Fla.)》2020,32(17):1907142
The synergistic integration of nanomaterials with 3D printing technologies can enable the creation of architecture and devices with an unprecedented level of functional integration. In particular, a multiscale 3D printing approach can seamlessly interweave nanomaterials with diverse classes of materials to impart, program, or modulate a wide range of functional properties in an otherwise passive 3D printed object. However, achieving such multiscale integration is challenging as it requires the ability to pattern, organize, or assemble nanomaterials in a 3D printing process. This review highlights the latest advances in the integration of nanomaterials with 3D printing, achieved by leveraging mechanical, electrical, magnetic, optical, or thermal phenomena. Ultimately, it is envisioned that such approaches can enable the creation of multifunctional constructs and devices that cannot be fabricated with conventional manufacturing approaches. 相似文献
105.
Ashish Kumar Bhandari Arunangshu Ghosh Immadisetty Vinod Kumar 《IEEE/CAA Journal of Automatica Sinica》2020,7(1):200-213
To overcome the shortcomings of 1D and 2D Otsu’s thresholding techniques, the 3D Otsu method has been developed. Among all Otsu’s methods, 3D Otsu technique provides the best threshold values for the multi-level thresholding processes. In this paper, to improve the quality of segmented images, a simple and effective multilevel thresholding method is introduced. The proposed approach focuses on preserving edge detail by computing the 3D Otsu along the fusion phenomena. The advantages of the presented scheme include higher quality outcomes, better preservation of tiny details and boundaries and reduced execution time with rising threshold levels. The fusion approach depends upon the differences between pixel intensity values within a small local space of an image; it aims to improve localized information after the thresholding process. The fusion of images based on local contrast can improve image segmentation performance by minimizing the loss of local contrast, loss of details and gray-level distributions. Results show that the proposed method yields more promising segmentation results when compared to conventional 1D Otsu, 2D Otsu and 3D Otsu methods, as evident from the objective and subjective evaluations. 相似文献
106.
Sanat Ghosh Jaykumar Vaidya Sawani Datta Ram Prakash Pandeya Digambar A. Jangade Ruta N. Kulkarni Kalobaran Maiti Arumugam Thamizhavel Mandar M. Deshmukh 《Advanced materials (Deerfield Beach, Fla.)》2020,32(37):2002220
High-temperature superconductors (HTSs) are important for potential applications and for understanding the origin of strong correlations. Bi2Sr2CaCu2O8+δ (BSCCO), a van der Waals material, offers a platform to probe the physics down to a unit-cell. Guiding the flow of electrons by patterning 2DEGS and oxide heterostructures has brought new functionality and access to new science. Similarly, modifying superconductivity in HTS locally, on a small length scale, is of immense interest for superconducting electronics. A route to modify superconductivity locally by depositing metal on the surface is reported here by transport studies on few unit-cell thick BSCCO. Deposition of chromium (Cr) on the surface over a selected area of BSCCO results in insulating behavior of the underlying region. Cr locally depletes oxygen in CuO2 planes and disrupts the superconductivity in the layers below. This technique of modifying superconductivity is suitable for making sub-micrometer superconducting wires and more complex superconducting devices. 相似文献
107.
Maximilian Moser Tania Cecilia Hidalgo Jokubas Surgailis Johannes Gladisch Sarbani Ghosh Rajendar Sheelamanthula Quentin Thiburce Alexander Giovannitti Alberto Salleo Nicola Gasparini Andrew Wadsworth Igor Zozoulenko Magnus Berggren Eleni Stavrinidou Sahika Inal Iain McCulloch 《Advanced materials (Deerfield Beach, Fla.)》2020,32(37):2002748
A series of glycolated polythiophenes for use in organic electrochemical transistors (OECTs) is designed and synthesized, differing in the distribution of their ethylene glycol chains that are tethered to the conjugated backbone. While side chain redistribution does not have a significant impact on the optoelectronic properties of the polymers, this molecular engineering strategy strongly impacts the water uptake achieved in the polymers. By careful optimization of the water uptake in the polymer films, OECTs with unprecedented steady-state performances in terms of [μC*] and current retentions up to 98% over 700 electrochemical switching cycles are developed. 相似文献
108.
Sumit Tetarave Somanath Tripathy Ratan Ghosh 《International Journal of Communication Systems》2020,33(15)
With the recent development of LTE‐A/5G technologies, data sharing among mobile devices offer an attractive opportunity to reduce Internet access. However, it requires smart strategies to share the data with low trade‐offs in time, cost, and energy. Several existing schemes offer a super‐peer‐based two‐tier model using a distributed hash table (DHT) organization for smart devices having device‐to‐device (D2D)/Bluetooth/WiFi capabilities. The primary focus of these schemes has been to reduce Internet usage by increased D2D content sharing. However, the real challenge is not in creating a two‐tier model, but evolving an efficient overlay that offers enhanced opportunities for D2D content sharing over the existing model. In this paper, we formulated a P‐median‐based selection of tier‐1 devices in a distribution network and solved it using the Lagrangian relaxation method. The tier‐2 devices become clients seeking content sharing services from tier‐1 devices. A strong motivation in this work is to raise a user's perception of the grade of service known as quality of experience (QoE). We analyzed the challenge for QoE assessment in resource‐constrained smartphones under the proposed model of enhanced D2D communication. Our focus is to establish a framework to evaluate QoE for applications and services over LTE‐A/5G networks with an improved D2D communication level. The simulation and the experimental results validate the claim that substantial improvements in QoE are possible with the proposed mathematical model for selecting and placing tier‐1 mobile devices and maintaining a DHT for D2D communication. 相似文献
109.
Surajit Sengupta Sanjoy Debnath Papai Ghosh Izhar Mustafa 《Journal of Natural Fibers》2020,17(8):1212-1224
ABSTRACT Banana fiber is a lingo-cellulosic under-exploited bast fiber, which obtained from the pseudo-stem of banana plant (Musa acuminata). In this study, an attempt has been made to explore the possibility of production of needle-punched nonwoven from fibrous material of biowaste for value addition and diversified uses. Mechanical processing for preparation of all banana, banana-jute (1:1), and banana-polypropylene (1:1) blended needle punched nonwoven has been optimized and processing parameters have been suggested. Softening treatment of banana fibre has been done successfully for better processing. Boiling in water with 1% nonionic detergent has been suggested as pre-processing for softening. Tenacity, elongation-at-break, initial modulus, breaking energy, stress relaxation, creep, compressibility, recovery-from-compression, bending load, electrical insulation, thermal insulation, sound insulation, air permeability, and frictional force have been evaluated and analyzed for all the above-mentioned samples. Based on those properties the probable use has been suggested as insulation (thermal and sound) and filter material. 相似文献
110.
Subhajit Ghosh Fariborz Kargar Amirmahdi Mohammadzadeh Sergey Rumyantsev Alexander A. Balandin 《Advanced Electronic Materials》2021,7(12):2100408
Low-frequency current fluctuations, i.e., noise, in the quasi-2D van der Waals antiferromagnetic semiconductor FePS3 with the electronic bandgap of 1.5 eV is investigated. The electrical and noise characteristics of the p-type, highly resistive, thin films of FePS3 are measured at different temperatures. The noise spectral density is of the 1/f-type over most of the examined temperature range but reveals well-defined Lorentzian bulges, and increases strongly near the Néel temperature TN = 118 K (f is the frequency). Intriguingly, the noise spectral density attains its minimum at temperature T ≈ 200 K, which is attributed to an interplay of two opposite trends in noise scaling—one for semiconductors and another for materials with the phase transitions. The Lorentzian corner frequencies reveal unusual dependence on temperature and bias voltage, suggesting that their origin is different from the generation—recombination noise in conventional semiconductors. The obtained results are important for proposed applications of antiferromagnetic semiconductors in spintronic devices. They also attest to the power of the noise spectroscopy for monitoring various phase transitions. 相似文献