83 results match your criteria voltage curing

Development of Rapid and High-Precision Colorimetric Device for Organophosphorus Pesticide Detection Based on Microfluidic Mixer Chip.

Micromachines (Basel) 2021 Mar 9;12(3). Epub 2021 Mar 9.

College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling 712100, China.

The excessive pesticide residues in cereals, fruit and vegetables is a big threat to human health, and it is necessary to develop a portable, low-cost and high-precision pesticide residue detection scheme to replace the large-scale laboratory testing equipment for rapid detection of pesticide residues. In this study, a colorimetric device for rapid detection of organophosphorus pesticide residues with high precision based on a microfluidic mixer chip was proposed. The microchannel structure with high mixing efficiency was determined by fluid dynamics simulation, while the corresponding microfluidic mixer chip was designed. Read More

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Enhancing Interfacial Contact in Solid-State Batteries with a Gradient Composite Solid Electrolyte.

Small 2021 May 19;17(18):e2006578. Epub 2021 Mar 19.

School of Materials Science & Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology, Beijing, 100081, China.

Solid-state batteries promise to meet the challenges of high energy density and high safety for future energy storage. However, poor interfacial contact and complex manufacturing processes limit their practical applications. Herein, a simple strategy is proposed to enhance interfacial contact by introducing a gradient composite polymer solid electrolyte (GCPE), which is prepared by a facile UV-curing polymerization technique. Read More

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Construction of Nanocrystalline Cellulose-Based Composite Fiber Films with Excellent Porosity Performances via an Electrospinning Strategy.

ACS Omega 2021 Feb 11;6(7):4958-4967. Epub 2021 Feb 11.

State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, P. R. China.

Cellulose nanocrystals (CNCs) not only have environmental protection characteristics of being lightweight, degradable, green, and renewable but also have some nanocharacteristics of high strength, large specific surface area, and obvious small size effect, so they are often used as a reinforcing agent in various polymers. However, the hydrogen bonding between CNC molecules is relatively strong, and they can easily aggregate and get entangled with each other. In this work, several large-porosity composite nanofiber films, KH550-CNC/waterborne polyurethane (WPU)/poly(vinyl alcohol) (PVAL) with KH550-modified CNCs, are prepared using poly(vinyl alcohol) (PVAL) solution and electrospinning technology. Read More

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February 2021

Using Dihydrazides as Thermal Latent Curing Agents in Epoxy-Based Sealing Materials for Liquid Crystal Displays.

Jun Hyup Lee

Polymers (Basel) 2020 Dec 29;13(1). Epub 2020 Dec 29.

Department of Chemical Engineering, Soongsil University, Seoul 06978, Korea.

In this study, highly adhesive epoxy-based sealing materials for liquid crystal (LC) displays were fabricated using different types of dihydrazides as thermal latent curing agents. Their curing characteristics, mechanical properties, LC contamination levels, and electro-optical characteristics were investigated depending on the chemical structure of dihydrazides. The epoxy-based sealing material containing a dihydrazide derivative with a bulky heterocyclic ring afforded a high heat curing conversion of 90. Read More

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December 2020

Nanopatterned Nafion microelectrode arrays for cardiac electrophysiology.

Adv Funct Mater 2020 Jun 22;30(25). Epub 2020 Apr 22.

Department of Biomedical Engineering and Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, United States.

In this study, we report nanopatterned Nafion microelectrode arrays for in vitro cardiac electrophysiology. With the aim of defining sophisticated Nafion nanostructures with highly ionic conductivity, fabrication parameters such as Nafion concentration and curing temperature were optimized. By increasing curing temperature and Nafion concentration, we were able to control the replication fidelity of Nafion nanopatterns when copied from a PDMS master mold. Read More

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Design of Multifunctional Composites: New Strategy to Save Energy and Improve Mechanical Performance.

Nanomaterials (Basel) 2020 Nov 18;10(11). Epub 2020 Nov 18.

Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano (SA), Italy.

In this paper, an alternative curing strategy, based on the application of an electric field, is proposed to harden nano-filled multifunctional resins. The resin is obtained through the dispersion of carbon nanotubes, which act as nanometric heater elements in the epoxy matrix. The electro-curing is activated by applying an external electric voltage, which allows tunable cross-linking within the epoxy matrix entrapped between the nanotubes. Read More

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November 2020

Evaluation of electrode-sample contact impedance under different curing humidity conditions during measurement of AC impedance of cement-based materials.

Sci Rep 2020 Oct 21;10(1):17968. Epub 2020 Oct 21.

College of Materials, Xiamen University, Xiamen, Fujian, 361005, People's Republic of China.

In this study, a simple method was proposed to calculate electrode-sample contact impedance in the cases of two-point and four-point measurements. The results indicated that when using the saturated calcium hydroxide solution (SCH) as conductive medium, the contact impedance in the four-point measurement is negligible for the impedance range of cement-based materials. The SCH can be used as a reference for correction of the contact impedance. Read More

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October 2020

Electromechanical Response and Residual Thermal Stress of Metal-Core Piezoelectric Fiber /Al Matrix Composites.

Sensors (Basel) 2020 Oct 13;20(20). Epub 2020 Oct 13.

Department of Frontier Science for Advanced Environment, Graduate School of Environmental Studies, Tohoku University, Sendai 980-8579, Japan.

It is well known that the curing residual stress induced during a fabrication process has a great influence on the performance of piezoelectric composite devices. The purpose of this work was to evaluate the residual thermal stress of lead zirconate titanate piezoelectric fiber aluminum (Al) matrix (piezoelectric fiber/Al) composites generated during fabrication and to understand the effect of the residual thermal stress on the electromechanical response. The three-dimensional finite element method was employed, and the residual stress generated during the solidification process of the Al matrix was calculated. Read More

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October 2020

Performance of Silicone Rubber Composites Filled with Aluminum Nitride and Alumina Tri-Hydrate.

Materials (Basel) 2020 May 29;13(11). Epub 2020 May 29.

School of Renewable Energy, North China Electric Power University, Beijing 102206, China.

In this study, silicone rubber (SR) composites were prepared with various amounts of aluminum nitride (AlN) and alumina tri-hydrate (ATH), and vinyl tri-methoxysilane (VTMS) was also introduced to prepare SR/ATH/AlN-VTMS composites for comparison. Compared to the SR/ATH composites, the SR/ATH/AlN composites with higher AlN loading exhibited higher breakdown strength and thermal conductivity, which were further improved by the addition of VTMS. Such results were related to the enhanced rubber-filler interfacial interactions from VTMS coupling, as demonstrated by scanning electron microscopy (SEM) analysis and the curing behaviors of the SR composites. Read More

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Distributed mobile ultraviolet light sources driven by ambient mechanical stimuli.

Nano Energy 2020 Aug 4;74:104910. Epub 2020 May 4.

State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing, China.

Due to the natural characteristics of high voltage output, Triboelectric Nanogenerators (TENGs) have huge advantages in many fields. Here, we have proposed a concept of Mobile ultraviolet light sources (Mobile-UV) driven by TENG, without any additional circuits. For this system, analysis of electric characteristics, optical emission spectra, and COMSOL simulation were carried out to promote the performance. Read More

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Comparison of the Depth of Cure of Flowable Composites Polymerized at Variable Increment Thicknesses and Voltages: An Study.

Contemp Clin Dent 2019 Apr-Jun;10(2):220-225

Department of Operative Dentistry, Aga Khan University Hospital, Karachi, Pakistan.

Objectives: The aim of this study is to compare the depth of cure of two composite materials (SDR and Filtek bulk-fill) cured at variable increment depths (2, 4, and 6 mm) and voltages (180 and 220 volts).

Materials And Methods: Each sample of the composite material was packed in a mold of 2 mm, 4 mm, and 6 mm and curing light (quartz tungsten halogen) of optimal intensity was exposed for 20 s at 2 different voltages on each specimen. After curing, the specimens were removed and the composite on the nonexposed end was scraped with a plastic instrument. Read More

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Solution-Processed LiO-AlO/TiO Nanolaminate Stacks Containing Mobile Lithium Ions and with Increased Breakdown Voltages.

ACS Appl Mater Interfaces 2020 Jan 26;12(1):1241-1249. Epub 2019 Dec 26.

Department of Chemistry and Biochemistry , University of Oregon , Eugene , Oregon 97403 , United States.

An aqueous solution approach has been utilized to prepare nanolaminates of TiO and ionically conductive LiO-AlO (LiAlO). This new approach utilizes low curing temperatures, resulting in fully oxidized films as demonstrated by Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. The layered structures have been characterized by scanning electron microscopy, X-ray diffraction, and X-ray reflectivity. Read More

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January 2020

Evaluation of physicochemical properties and volatile compounds of Chinese dried pork loin curing with plasma-treated water brine.

Sci Rep 2019 09 24;9(1):13793. Epub 2019 Sep 24.

National Center of Meat Quality and Safety Control, Synergetic Innovation Center of Food Safety and Nutrition, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, PR China.

The application of dielectric barrier discharge cold plasma (DBD-CP)-treated water as a novel curing process for manufacturing Chinese dried pork loin was investigated. The treatment time of DBD-CP was optimized based on the pH and nitrite level of the plasma-treated water (PTW). PTW treated for 3 min had an alkaline environment and a higher nitrite content than that at the other lengths of treatment time. Read More

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September 2019

Shape programming of polymeric based electrothermal actuator (ETA) via artificially induced stress relaxation.

Sci Rep 2019 Aug 7;9(1):11445. Epub 2019 Aug 7.

Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Canada.

Electrothermal actuators (ETAs) are a new generation of active materials that can produce different motions from thermal expansion induced by Joule heating. It is well-known that the degree of deformation is determined by the amount of Joule heating and the coefficient of thermal expansion (CTE) of the material. Previous works on polymeric ETAs are strongly focused on increasing electrical conductivity by utilizing super-aligned carbon nanotube (CNT) sheets. Read More

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Self curing and voltage activated catechol adhesives.

Chem Commun (Camb) 2019 Aug;55(68):10076-10079

School of Materials Science and Engineering (MSE), Division of Materials Technology, Nanyang Technological University (NTU), Singapore 639798.

Catechol adhesives are limited to two-part curing designs. For the first time, a one-pot catechol adhesive is demonstrated with multiple modes of external activation: self-curing, electrocuring, substrate, and two-part curing. Lap shear adhesion (50 kPa) and viscoelastic properties demonstrate that electrocuring is non-inferior to two-part curing methods. Read More

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One-Bath Pretreatment for Enhancing the Color Yield and Anti-Static Properties of Inkjet Printed Polyester Using Disperse Inks.

Materials (Basel) 2019 Jun 5;12(11). Epub 2019 Jun 5.

College of Textile and Clothing Engineering, Soochow University, Suzhou 215021, China.

This paper presents a simple and economical method for preparing durable anti-static functionalized inkjet prints by using P[St-BA-F6]-novel antistatic agents synthesized by an oxidative polymerization of styrene, butyl acrylate, and allyl alcohol polyether F6. The P[St-BA-F6] was characterized by gel permeation chromatography and Fourier transformation infrared spectroscopy. One bath pretreatment solution containing P[St-BA-F6] and pentaerythritol tetraacrylate (PETA) were applied to polyester fabrics before inkjet printing, in order to enhance the color yield and the anti-static properties. Read More

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Hole-Transporting Side-Chain Polymer Bearing a Thermally Crosslinkable Bicyclo[4.2.0]octa-1,3,5-trien-3-yl Group for High-Performing Thermally Activated Delayed Fluorescence OLED.

ACS Appl Mater Interfaces 2019 May 1;11(19):17602-17609. Epub 2019 May 1.

Department of Chemistry, Research Institute for Natural Sciences , Korea University , 145 Anam-ro , Sungbuk-gu, Seoul 02841 , Korea.

A new side-chain polymer (X-TPACz) bearing hole-transporting pendant groups accompanying a thermally crosslinkable entity was synthesized using N-([1,1'-biphenyl]-4-yl)- N-(4-(9-(4-vinylbenzyl)-9 H-carbazol-3-yl)phenyl)bicyclo[4.2.0]octa-1(6),2,4-trien-3-amine (6) via addition polymerization. Read More

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Electrically Conductive CNT Composites at Loadings below Theoretical Percolation Values.

Nanomaterials (Basel) 2019 Mar 29;9(4). Epub 2019 Mar 29.

Department of Mechanical and Aerospace Engineering, Naval Postgraduate School, Monterey, CA 93943, USA.

It is well established that dramatic increases in conductivity occur upon the addition of conductive filler materials to highly resistive polymeric matrices in experimental settings. However, the mechanisms responsible for the observed behavior at low filler loadings, below theoretical percolation limits, of even high aspect ratio fillers such as carbon nanotubes (CNT) are not completely understood. In this study, conductive composites were fabricated using CNT bundles dispersed in epoxy resins at diverse loadings, using different dispersion and curing protocols. Read More

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395 nm GaN-based near-ultraviolet light-emitting diodes on Si substrates with a high wall-plug efficiency of 52.0%@350 mA.

Opt Express 2019 Mar;27(5):7447-7457

The high-performance 395 nm GaN-based near-ultraviolet (UV) light emitting diodes (LEDs) on Si substrates have been obtained by designing an AlN buffer layer to decrease the dislocations density of the GaN layer. By adopting a multi-layer structure with a high- and low-V/III ratio alternation, a high-quality AlN buffer layer has been obtained with a small full-width at half-maximum (FWHM) for AlN(0002) X-ray rocking curve (XRC) of 648 arcsec and a small root-mean-square roughness of 0.11 nm. Read More

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UV-Cured Hafnium Oxide-Based Gate Dielectrics for Low-Voltage Organic and Amorphous Oxide Thin-Film Transistors.

J Nanosci Nanotechnol 2019 Jul;19(7):4249-4253

Department of Chemistry, Kyonggi University, Suwon, Gyeonggi-Do 443-760, Republic of Korea.

In this study, we have fabricated hafnium oxide dielectrics for low-voltage organic and amorphous oxide thin-film transistors (TFTs) via a facile low-temperature solution method and investigated the electrical properties of these dielectrics. Hafnium oxide dielectric films can be easily fabricated by a sol-gel solution method and ultraviolet (UV) curing at room temperature. In addition, the surface energy of hafnium oxide films can be easily modified by using phosphonic-acid-based self-assembled monolayers. Read More

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Evolving Mechanistic Concepts of Epileptiform Synchronization and their Relevance in Curing Focal Epileptic Disorders.

Curr Neuropharmacol 2019 ;17(9):830-842

Montreal Neurological Institute, McGill University, Montreal, H3A 2B4 Quebec, Canada.

The synchronized activity of neuronal networks under physiological conditions is mirrored by specific oscillatory patterns of the EEG that are associated with different behavioral states and cognitive functions. Excessive synchronization can, however, lead to focal epileptiform activity characterized by interictal and ictal discharges in epileptic patients and animal models. This review focusses on studies that have addressed epileptiform synchronization in temporal lobe regions by employing in vitro and in vivo recording techniques. Read More

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February 2020

Slow Response of Carrier Dynamics in Perovskite Interface upon Illumination.

ACS Appl Mater Interfaces 2018 Sep 10;10(37):31452-31461. Epub 2018 Sep 10.

Center for Micro-Photonics , Swinburne University of Technology , Hawthorn VIC3122 , Australia.

The current-voltage hysteresis, as well as the performance instability of perovskite solar cells (PSCs) under a working condition, is serving as the major obstacle toward their commercialization while the exact fundamental mechanisms to these issues are still in debate. In this study, we investigated the slow variation of photogenerated carrier dynamics in a (FAPbI)(MAPbBr) perovskite interface under continuous illumination. Different response behaviors of carrier dynamics in the perovskite interfaces with and without the hole transport layer, Spiro-OMeTAD (Spiro), were systematically studied by time-dependent, steady-state, and time-resolved photoluminescence. Read More

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September 2018

Process for a Reactive Monomer Alignment Layer for Liquid Crystals Formed on an Azodye Sublayer.

Materials (Basel) 2018 Jul 12;11(7). Epub 2018 Jul 12.

Liquid Crystal Institute, Kent State University, Kent, OH 44242, USA.

In this work, the detailed studies of surface polymerization stabilizing liquid crystal formed on an azodye sublayer are presented. The surface localized stabilization is obtained by free-radical polymerization of a dilute solution of a bi-functional reactive monomer (RM) in a liquid crystal (LC) solvent. To optimize the process for surface localized stabilization, we investigate the effects of several process parameters including RM concentration in LC hosts, the types of materials (either RM or LC), the photo-initiator (PI) concentration, ultra-violet (UV) polymerization intensity, and the UV curing temperature. Read More

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Pressure characteristics of a self-Q-switched distributed Bragg reflector fiber laser.

Appl Opt 2018 Jun;57(16):4467-4471

Based on the study of self-Q-switching of a short cavity erbium-doped distributed Bragg reflector (DBR) fiber laser in time domain, the influence of pressure disturbance on the self-Q-switched output is analyzed. In the experiment, the erbium-doped DBR fiber laser (EDFL) was encapsulated with epoxy resin and curing agent to protect and sensitize the fiber. The EDFL sends out self-Q-switched laser pulses when the pump power of the 980 nm laser source is more than 110 mW. Read More

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Immediate effects of temporary bite-raising with light-cured orthodontic band cement on the electromyographic response of masticatory muscles.

J Appl Oral Sci 2018 May 14;26:e20170214. Epub 2018 May 14.

Faculty of Dentistry, Department of Orthodontics, Chulalongkorn University, Bangkok, Thailand.

To assess the immediate effects of temporary bite-raising using light-cured orthodontic band cement on the superficial masseter and anterior temporalis electromyography (EMG) activity in healthy adults. Surface EMG signals were recorded bilaterally from the superficial masseter and anterior temporalis muscles of 30 volunteers with a normal occlusion, before and after having temporary bite-raising. The bite-raising was done by adding light-cured orthodontic band cement (3x5x2 mm WxLxH) on the lingual cusps of both upper first molars. Read More

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High performance printed oxide field-effect transistors processed using photonic curing.

Nanotechnology 2018 Jun 19;29(23):235205. Epub 2018 Mar 19.

Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), D-76344 Eggenstein-Leopoldshafen, Germany.

Oxide semiconductors are highly promising candidates for the most awaited, next-generation electronics, namely, printed electronics. As a fabrication route for the solution-processed/printed oxide semiconductors, photonic curing is becoming increasingly popular, as compared to the conventional thermal curing method; the former offers numerous advantages over the latter, such as low process temperatures and short exposure time and thereby, high throughput compatibility. Here, using dissimilar photonic curing concepts (UV-visible light and UV-laser), we demonstrate facile fabrication of high performance InO field-effect transistors (FETs). Read More

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Performance enhancement using a stable low-pretilt molecular configuration and a novel driving method for optically compensated bend liquid crystal devices.

Opt Lett 2018 Feb;43(3):571-574

A stable low-pretilt molecular configuration (SLPMC) is successfully developed in optically compensated bend (OCB) liquid crystal (LC) devices by simultaneously employing the curing voltage and surface-anchored crosslinking monomer during the polymerization process. For the SLPMC OCB cell with the low-bend state, the warm-up voltage making the LC molecules reorient from the splay to the bend state is annihilated, and the transient twist state occurring as the driven LC molecules recover from the bend to the splay state is also eliminated. In addition, with the novel driving method selecting the specific driving point, the proposed SLPMC OCB cell not only exhibits a good response performance, but also outputs a higher light transmittance, which is superior to the conventional OCB and no-bias-bend cells. Read More

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February 2018

In-situ poling and structurization of piezoelectric particulate composites.

J Intell Mater Syst Struct 2017 Nov 1;28(18):2467-2472. Epub 2017 Feb 1.

Novel Aerospace Materials Group, Faculty of Aerospace Engineering, Delft University of Technology, The Netherlands.

Composites of lead zirconate titanate particles in an epoxy matrix are prepared in the form of 0-3 and quasi 1-3 with different ceramic volume contents from 10% to 50%. Two different processing routes are tested. Firstly a conventional dielectrophoretic structuring is used to induce a chain-like particle configuration, followed by curing the matrix and poling at a high temperature and under a high voltage. Read More

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November 2017

Effects of Declining Battery Voltage on Light Intensity and Power Consumption of Light-Curing.

J Clin Orthod 2017 Jul;51(7):411-418

Department of Orthodontics, Faculty of Denistry, Ordu University, Altinordu, Ordu 52100, Turkey.

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The Effect of Particles on Electrolytically Polymerized Thin Natural MCF Rubber for Soft Sensors Installed in Artificial Skin.

Sensors (Basel) 2017 Apr 19;17(4). Epub 2017 Apr 19.

Department of Biomedical Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama 350-8585, Japan.

The aim of this study is to investigate the effect of particles as filler in soft rubber sensors installed in artificial skin. We examine sensors made of natural rubber (NR-latex) that include magnetic particles of Ni and Fe₃O₄ using magnetic compound fluid (MCF). The 1-mm thickness of the electrolytically polymerized MCF rubber makes production of comparatively thin rubber sensors feasible. Read More

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