Modification of Deposition Process of Piezoelectric Polycrystalline Film by Hydrothermal Method -Improvement of the Deposition Process by Pre-Treatment Using Hydrogen Peroxide

2005 ◽  
Vol 872 ◽  
Author(s):  
Akito Endo ◽  
Norimichi Kawashima ◽  
Shinichi Takeuchi ◽  
Mutsuo Ishikawa ◽  
Minoru Kurosawa
Keyword(s):  
Hydrogen Peroxide ◽  
Electric Field ◽  
Thick Film ◽  
Dielectric Breakdown ◽  
Deposition Process ◽  
High Reactivity ◽  
Polycrystalline Film ◽  
Hydrophilic Property ◽  
Breakdown Electric Field ◽  
Pre Treatment

AbstractWe have studied on hydro-thermally synthesis of Pb(Ti, Zr)O3(PZT)piezoelectric polycrystalline thick film on titanium (Ti) substrate. The purpose of this study is resolving the problems for application of PZT hydrothermal polycrystalline thick film to the ultra miniature high frequency medical ultrasound array probe. The problems were the existence of pinholes in the deposited PZT film, the rough surface of that, low dielectric breakdown electric field etc. The surface of Ti substrate was pretreated to have hydrophilic property by using high reactivity of hydrogen peroxide for resolving the problems in this study. As results, hydrophilic property on the surface of Ti substrate was improved. Surface of PZT hydrothermal polycrystalline thick film without pinholes and smooth surface of that were obtained. Furthermore, the material properties like density, Young's modulus and piezoelectric constant d31 were increased by the pretreatment of Ti substrate. Consequently, dielectric breakdown electric field of PZT hydrothermal polycrystalline film was improved.

An investigation of dielectric breakdown on a pressurized, flowing oil switch - WITHDRAWN

2009 ◽  
Author(s):  
◽  
Peter A. Norgard
Keyword(s):  
Electric Field ◽  
Rise Time ◽  
High Performance ◽  
Dielectric Breakdown ◽  
High Energy ◽  
Operating Characteristics ◽  
University Of Missouri ◽  
Breakdown Electric Field ◽  
Alpha Olefin ◽  
Oil Flow

WITHDRAWN - [ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] In the not-so-distant future, a need is foreseen for a high-performance, compact switch that is capable of repetitively switching kilovolts to megavolts and several hundred joules, all while delivering a square pulse with a fast current rise time. Many industrial and military applications currently exist that could take advantage of these operating characteristics, and many more are surely to be developed in the coming years. The proposed approach to realizing the goal of producing a fast rise time, high voltage, high energy, repetitive switch technology is to employ a pressurized, flowing oil dielectric switching medium. Oil pressure and oil flow will be used to increase the rate of dielectric recovery following a high energy discharge, thus enabling a much higher operating repetition frequency; oil pressure will be utilized to control gaseous switching byproducts, and oil flow will be utilized to control solid and gaseous switching byproducts. The well-known increase in breakdown electric field strength with increasing oil pressure will be utilized to reduce the gap separation, thus reducing the inductance of the electrical arc and increasing the rise time of the current pulse produced during breakdown. An experiment was designed and undertaken to evaluate the complete statistical performance of the breakdown electric field of an emerging dielectric liquid, poly-[alpha]olefin, with respect to variations in oil pressure, oil flow rate, peak rate of rise of the voltage, and gap separation.

scholarly journals USING A RE-ENTRANT MICROWAVE RESONATOR TO MEASURE AND MODEL THE DIELECTRIC BREAKDOWN ELECTRIC FIELD OF GASES

2009 ◽  
Vol 15 ◽  
pp. 175-195 ◽  
Author(s):  
Stephen K. Remillard ◽  
Alejandro Hardaway ◽  
B. Mork ◽  
Jake Gilliland ◽  
Joseph Gibbs
Keyword(s):  
Electric Field ◽  
Dielectric Breakdown ◽  
Microwave Resonator ◽  
Breakdown Electric Field

scholarly journals Selected Kefir Water from Malaysia Attenuates Hydrogen Peroxide-Induced Oxidative Stress by Upregulating Endogenous Antioxidant Levels in SH-SY5Y Neuroblastoma Cells

Antioxidants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 940
Author(s):  
Muganti Rajah Kumar ◽  
Swee Keong Yeap ◽  
Han Chung Lee ◽  
Nurul Elyani Mohamad ◽  
Muhammad Nazirul Mubin Aziz ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Neuroblastoma Cells ◽  
Annexin V ◽  
Morphological Features ◽  
Lower Percentage ◽  
Total Phenolic ◽  
Neuroprotective Effects ◽  
Antioxidant Power ◽  
Pre Treatment

Kefir, a fermented probiotic drink was tested for its potential anti-oxidative, anti-apoptotic, and neuroprotective effects to attenuate cellular oxidative stress on human SH-SY5Y neuroblastoma cells. Here, the antioxidant potentials of the six different kefir water samples were analysed by total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP), and 2,2′-diphenyl-1-picrylhydrazyl radical (DPPH) assays, whereas the anti-apoptotic activity on hydrogen peroxide (H2O2) induced SH-SY5Y cells was examined using MTT, AO/PI double staining, and PI/Annexin V-FITC assays. The surface and internal morphological features of SH-SY5Y cells were studied using scanning and transmission electron microscopy. The results indicate that Kefir B showed the higher TPC (1.96 ± 0.54 µg GAE/µL), TFC (1.09 ± 0.02 µg CAT eq/µL), FRAP (19.68 ± 0.11 mM FRAP eq/50 µL), and DPPH (0.45 ± 0.06 mg/mL) activities compared to the other kefir samples. The MTT and PI/Annexin V-FITC assays showed that Kefir B pre-treatment at 10 mg/mL for 48 h resulted in greater cytoprotection (97.04%), and a significantly lower percentage of necrotic cells (7.79%), respectively. The Kefir B pre-treatment also resulted in greater protection to cytoplasmic and cytoskeleton inclusion, along with the conservation of the surface morphological features and the overall integrity of SH-SY5Y cells. Our findings indicate that the anti-oxidative, anti-apoptosis, and neuroprotective effects of kefir were mediated via the upregulation of SOD and catalase, as well as the modulation of apoptotic genes (Tp73, Bax, and Bcl-2).

scholarly journals Metal-catalyzed oxidation renders silver intensification selective. Applications for the histochemistry of diaminobenzidine and neurofibrillary changes.

1986 ◽  
Vol 34 (12) ◽  
pp. 1667-1672 ◽  
Author(s):  
F Gallyas ◽  
J R Wolff
Keyword(s):  
Hydrogen Peroxide ◽  
Oxidative Polymerization ◽  
Silver Coating ◽  
Neurofibrillary Changes ◽  
Iodide Ions ◽  
Tissue Sections ◽  
Metal Catalyzed Oxidation ◽  
Pre Treatment ◽  
Metal Catalyzed ◽  
Catalyzed Oxidation

Physical developers can increase the visibility of end products of certain histochemical reactions, such as oxidative polymerization of diaminobenzidine and selective binding of complex silver iodide ions to Alzheimer's neurofibrillary changes. Unfortunately, this intensification by silver coating is generally superimposed on a nonspecific staining originating from the argyrophil III reaction, which also takes place when tissue sections are treated with physical developers. The present study reveals that the argyrophil III reaction can be suppressed when tissue sections are treated with certain metal ions and hydrogen peroxide before they are transferred to the physical developer. The selective intensification of Alzheimer's neurofibrillary changes requires a pre-treatment with lanthanum nitrate (10 mM/liter) and 3% hydrogen peroxide for 1 hr. The diaminobenzidine reaction can be selectively intensified when physical development is preceded by consecutive treatments with copper sulfate (10 mM/liter, pH 5, 10 min) and hydrogen peroxide (3%, pH 7, 10 min). In peroxidase histochemistry, this high-grade intensification may help to increase specificity and reduce the threshold of detectability in tracing neurons with horseradish peroxidase or in immunohistochemistry when the peroxidase-antiperoxidase method is used.

scholarly journals Charging of Piezoelectric Cellular Polypropylene Film by Means of a Series Dielectric Layer

Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 333
Author(s):  
Pedro Llovera-Segovia ◽  
Gustavo Ortega-Braña ◽  
Vicente Fuster-Roig ◽  
Alfredo Quijano-López
Keyword(s):  
Electric Field ◽  
Corona Discharge ◽  
Dielectric Layer ◽  
Dielectric Breakdown ◽  
Piezoelectric Materials ◽  
High Resistivity ◽  
Internal Electric Field ◽  
Dielectric Polarization ◽  
Surface Flashover ◽  
In Series

Piezoelectric polymer cellular films have been developed and improved in the past decades. These piezoelectric materials are based on the polarization of the internal cells by means of induced discharges in the gas inside the cells. Internal discharges are driven by an external applied electric field. With this polarization method, cellular polypropylene (PP) polymers exhibit a high piezoelectric coefficient d33 and have been investigated because of their low dielectric polarization, high resistivity, and flexibility. Charging polymers foams is normally obtained by applying a corona discharge to the surface with a single tip electrode-plane arrangement or a triode electrode, which consists of a tip electrode-plane structure with a controlled potential intermediate mesh. Corona charging allows the surface potential of the sample to rise without breakdown or surface flashover. A charging method has been developed without corona discharge, and this has provided good results. In our work, a method has been developed to polarize polypropylene foams by applying an insulated high-voltage electrode on the surface of the sample. The dielectric layer in series with the sample allows for a high internal electric field to be reached in the sample but avoids dielectric breakdown of the sample. The distribution of the electric field between the sample and the dielectric barrier has been calculated. Experimental results with three different electrodes present good outcome in agreement with the calculations. High d33 constants of about 880 pC/N have been obtained. Mapping of the d33 constant on the surface has also been carried out showing good homogeneity on the area under the electrode.

Effect of Static High Electric Field Pre-Treatment on Microwave-Assisted Drying of Potato Slices

2013 ◽  
Vol 31 (16) ◽  
pp. 1960-1968 ◽  
Author(s):  
Ashutosh Singh ◽  
Gopu Raveendran Nair ◽  
Jamshid Rahimi ◽  
Yvan Gariepy ◽  
Vijaya Raghavan
Keyword(s):  
Electric Field ◽  
High Electric Field ◽  
Microwave Assisted ◽  
Pre Treatment ◽  
Potato Slices

scholarly journals Hydrogen peroxide pre-treatment for seed enhancement in Cotton (Gossypim hirsutum L.)

2014 ◽  
Vol 9 (25) ◽  
pp. 1982-1989 ◽  
Author(s):  
Santhy V. ◽  
Meshram M. ◽  
Wakde R. ◽  
R. Vijaya Kumari P.
Keyword(s):  
Hydrogen Peroxide ◽  
Pre Treatment

Peroxide Pre-Oxidation of Recalcitrant Toxic Waste to Enhance Biodegradation

1991 ◽  
Vol 23 (1-3) ◽  
pp. 367-376 ◽  
Author(s):  
J. B. Carberry ◽  
T. M. Benzing
Keyword(s):  
Hydrogen Peroxide ◽  
Toxic Waste ◽  
Organic Chemical ◽  
Organic Chemicals ◽  
Aqueous Systems ◽  
Industrial Chemicals ◽  
Soil Systems ◽  
Oxidation Technology ◽  
Land Disposal ◽  
Pre Treatment

Land disposal is required for industrial chemicals which are not readily biodegraded. Such compounds lead to adverse effects on the environment if they escape containment. Recalcitrant and persistent hydrocarbons and chlorinated chemicals are inherently resistant to any degree of biodegradation and cause a growing threat to underground aquifer quality. Hydrogen peroxide is a potentially economical method of pre-oxidation utilized to enhance the biodegradation of persistent and recalcitrant organics in contaminated soil systems. This pre-oxidation technology was examined in a laboratory respirometer using three model toxic organic chemicals: toluene, trichloroethylene and pentachlorophenol. Microbial cultures were selected from contaminated sites for the degradation of each model organic chemical. The rate at which the microbes degraded the organic chemicals in unoxidized aqueous systems was compared to the rate of degradation in peroxide pre-oxidized aqueous systems. Results indicated that pre-oxidation enhanced the biodegradation of trichloroethylene and pentachlorophenol. Toluene, in contrast, was not significantly oxidized by pretreatment with hydrogen peroxide, and its biodegradation rate was not enhanced by the oxidation pre-treatment process.

scholarly journals Size and temperature effects on dielectric breakdown of ferroelectric films

2020 ◽  
Author(s):  
Sheng Tong
Keyword(s):  
Energy Density ◽  
Electric Field ◽  
Dielectric Breakdown ◽  
Breakdown Strength ◽  
Operating Temperature ◽  
Electric Energy ◽  
Ferroelectric Films ◽  
Lead Lanthanum Zirconate Titanate ◽  
Dimensional Parameters ◽  
Electric Energy Density

Abstract The paper introduces a model of dielectric breakdown strength. The model integrated thermal breakdown and defect models, representing the relationship between the electric field of ferroelectric films and dimensional parameters and operating temperature. This model is verified with experimental results of the lead lanthanum zirconate titanate (PLZT) films of various film thickness (d = 0.8 – 3 mm), electrode area (A = 0.0020 – 25 mm2) tested under a range of operating temperature (T = 300 – 400 K) with satisfying fitting results. Also learned is a relationship that the recoverable electric energy density is directly proportional to the square of breakdown electric field. This relationship is found viable in predicting the electric energy density in terms of variables of d, A, and T for the PLZT films.

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