Electrical Properties of Flames. BurnerFlames in Longitudinal Electric Fields.

1951 ◽  
Vol 43 (12) ◽  
pp. 2726-2731 ◽  
Author(s):  
Hartwell F. Calcote ◽  
Robert N. Pease
Keyword(s):  
Electrical Properties ◽  
Electric Fields

Surface confinement induces the formation of solid-like insulating ionic liquid nanostructures

2017 ◽  
Author(s):  
Massimiliano Galluzzi ◽  
Simone Bovio ◽  
Paolo Milani ◽  
Alessandro Podestà
Keyword(s):  
Ionic Liquid ◽  
Electrical Properties ◽  
Electric Fields ◽  
Relative Dielectric Constant ◽  
Ionic Mobility ◽  
Electric Properties ◽  
Bulk Liquid ◽  
Structural Reorganization ◽  
Surface Confinement ◽  
Insulator Layers

We report on the modification of the electric properties of the imidazolium-based [BMIM][NTf2] ionic liquid upon surface confinement in the sub-monolayer regime. Solid-like insulating nanostructures of [BMIM][NTf2] spontaneously form on a variety of insulating substrates, at odd with the liquid and conductive nature of the same substances in the bulk phase. A systematic spatially resolved investigation by atomic force microscopy of the morphological, mechanical and electrical properties of [BMIM][NTf2] nanostructures showed that this liquid substance rearranges into lamellar nanostructures with a high degree of vertical order and enhanced resistance to mechanical compressive stresses and very intense electric fields, denoting a solid-like character. The morphological and structural reorganization has a profound impact on the electric properties of supported [BMIM][NTf2] islands, which behave like insulator layers with a relative dielectric constant between 3 and 5, comparable to those of conventional ionic solids, and significantly smaller than those measured in the bulk ionic liquid. These results suggest that in the solid-like ordered domains confined either at surfaces or inside the pores of the nanoporous electrodes of photo-electrochemical devices, the ionic mobility and the overall electrical properties can be significantly perturbed with respect to the bulk liquid phase, which would likely influence the<br>performance of the devices.<br>

Doping and Charging in Colloidal Semiconductor Nanocrystals

MRS Bulletin ◽  
2001 ◽  
Vol 26 (12) ◽  
pp. 1005-1008 ◽  
Author(s):  
Moonsub Shim ◽  
Congjun Wang ◽  
David J. Norris ◽  
Philippe Guyot-Sionnest
Keyword(s):  
Electrical Properties ◽  
Crystal Lattice ◽  
Electric Fields ◽  
Semiconductor Devices ◽  
Semiconductor Nanocrystals ◽  
Semiconductor Technology ◽  
Semiconductor Crystal ◽  
Impurity Atoms ◽  
Colloidal Semiconductor Nanocrystals ◽  
Colloidal Semiconductor

Modern semiconductor technology has been enabled by the ability to control the number of carriers (electrons and holes) that are available in the semiconductor crystal. This control has been achieved primarily with two methods: doping, which entails the introduction of impurity atoms that contribute additional carriers into the crystal lattice; and charging, which involves the use of applied electric fields to manipulate carrier densities near an interface or junction. By controlling the carriers with these methods, the electrical properties of the semiconductor can be precisely tailored for a particular application. Accordingly, doping and charging play a major role in most modern semiconductor devices.

Electrical Characterization of the Grain-Boundary Region of SnO2 Varistors

2006 ◽  
Vol 518 ◽  
pp. 235-240 ◽  
Author(s):  
M. Žunić ◽  
Z. Branković ◽  
G. Branković ◽  
D. Poleti
Keyword(s):  
Electrical Properties ◽  
Grain Boundary ◽  
Electric Fields ◽  
Electrical Characterization ◽  
Boundary Region ◽  
Current Voltage ◽  
Schottky Type ◽  
Boundary Properties ◽  
Current Voltage Characteristics

The effect of Co, Cr and Nb on the electrical properties of the grain boundaries of SnO2-based varistors was investigated. The powders were prepared by the method of evaporation and decomposition of solutions and suspensions. Varistor samples were obtained by uniaxial pressing followed by sintering at 1300 °C for 1h. The electrical properties of the grain-boundary region, such as resistance (R) and capacitance (C), were determined using ac impedance spectroscopy in the 27-330 °C temperature interval. Activation energies for conduction (EA) were calculated from the Arrhenius equation. The non-linear coefficients (α) and the breakdown electric fields (Eb) of the samples were determined from the current-voltage characteristics. The potential barrier height (Φb) was calculated using the Schottky-type conducting model. After a comparison of the characteristic parameters for different varistor compositions it was found that the Cr/Nb ratio has a crucial influence on the grain-boundary properties in SnO2 varistors.

Influence of Currents and Electric Fields in YNMO Ceramics

2017 ◽  
Vol 866 ◽  
pp. 256-258
Author(s):  
Naphat Albutt ◽  
Suejit Pechprasarn ◽  
Thanapong Sareein
Keyword(s):  
Dielectric Properties ◽  
Solid State ◽  
Electrical Properties ◽  
Electric Fields ◽  
Sintering Temperature ◽  
Ceramic Materials ◽  
Solid State Reaction Method ◽  
Electronic Components ◽  
Reaction Method ◽  
A Current

Development of ceramic materials is critical for new and improved electronic applications. Herein, the J-E response of Y2NiMnO6 (YNMO) ceramics composited by a solid state reaction method was investigated. Sintering temperature and time were found to have significant influence on the ceramics electrical properties. In particular, higher temperatures and longer sintering times resulted in more favourable dielectric properties of the YNMO ceramics. A current of 40 mA/cm2 at 20,000 mV/cm was obtained by sintering at 1300 °C for 12 hours, whereas a current of 9 mA/cm2 at 4000 mV/cm can be achieved by sintering at 1400 °C for 24 hours. These results will be useful for identifying applications for YNMO ceramics. The electrical properties of the YNMO ceramics can be tuned for different electronic components such as dry batteries and capacitors.

scholarly journals CBMT-13. 3DEP SYSTEM TO TEST THE ELECTRICAL PROPERTIES OF DIFFERENT CELL LINES AS PREDICTIVE MARKERS OF OPTIMAL TUMOR TREATING FIELDS (TTFIELDS) FREQUENCY AND SENSITIVITY

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi35-vi35
Author(s):  
Moshe Giladi ◽  
Einav Zeevi ◽  
Karnit Gotlib ◽  
Cornelia Wenger ◽  
Ariel Naveh ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Cell Line ◽  
Cell Lines ◽  
Electric Fields ◽  
Intermediate Frequency ◽  
Predictive Markers ◽  
Membrane Capacitance ◽  
Frequency Range ◽  
Optimal Frequency ◽  
Tumor Treating Fields

Abstract BACKGROUND Tumor Treating Fields (TTFields; approved anti-neoplastic treatment modality) are delivered via application of low intensity, intermediate frequency, alternating electrical fields. The electrical properties of cells (eg, permittivity and conductivity) determine the optimal TTFields frequency that would elicit the greatest cell count reduction. Currently, no predictive markers exist to determine TTFields response and optimal frequency for individual patient application. The study goal was to evaluate the correlation between electrical properties of cells and TTFields’s optimal frequency and sensitivity. The 3DEPTM reader (LabTech) determines cellular electrical properties, including permittivity and conductivity, by using dielectrophoresis (DEP) force. DEP is a physical effect that generates a force on polarizable particles, such as cells, subjected to non-uniform electric fields. METHODS Utilizing the 3DEP reader, baseline electrical properties (permittivity and conductivity) of 17 cell lines from different tumor-types were determined. Curves were analyzed using 2-way ANOVA. The optimal TTFields frequency of each cell line was determined by evaluating TTFields cytotoxicity at various frequencies using the inovitroTM system. Electrical properties of each cell line were compared with the optimal TTFields frequency and sensitivity. RESULTS Significant differences (P< 0.001) were demonstrated between the lower frequency range of the 3DEP curves that correspond to cellular membrane capacitance at TTFields optimal frequencies of 150 kHz (9 cell lines) and 200 kHz (8 cell lines). Also, membrane capacitance was a good predictor of TTFields sensitivity based on curve differences within the low-frequency range. CONCLUSIONS These results demonstrate that cell membrane capacitance correlates with TTFields optimal frequency and sensitivity. Based on these data, there is a strong rational to further explore the potential of measuring the electrical properties of cells as predictive markers to help determine the optimal TTFields frequency for individual patient application and to identify ideal treatment-responders to TTFields.

scholarly journals P11.25 Assessing electrical properties of cells as predictive marker for patient-specific TTFields response and optimal frequency

2019 ◽  
Vol 21 (Supplement_3) ◽  
pp. iii48-iii48
Author(s):  
A Kinzel ◽  
E Zeevi ◽  
K Gotlib ◽  
C Wenger ◽  
A Naveh ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Cell Lines ◽  
Electric Fields ◽  
Predictive Marker ◽  
Membrane Capacitance ◽  
Patient Specific ◽  
Optimal Frequency ◽  
Tumor Treating Fields ◽  
Mitotic Frequency ◽  
Tumor Types

Abstract BACKGROUND Tumor treating fields (TTFields) are currently approved for the treatment of glioblastoma multiforme (GBM, using 200 kHz), and being tested in other tumor types such as non-small cell lung cancer and brain metastases occurring in this indication (LUNAR and METIS trials, using 150 kHz). Response to TTFields in cancer cells was empirically shown to be frequency-dependent specific for cell type; however, there are no markers available predicting optimal frequency or response in different cancer types or individual patients to date. There is evidence indicating electrical properties determine the optimal anti-mitotic frequency. This study analyzed the correlation of electrical properties of cells with their optimal TTFields frequency and sensitivity using the 3DEP reader (LabTech) to determine the electrical properties with the help of Dielectrophoresis (DEP) force. With this technique, cell movements within electric fields of different frequencies can by analyzed based on the physical effect of DEP, exercising a force on polarizable particles inside a non-homogeneous electric field. MATERIAL AND METHODS We used the 3DEP reader to obtain baseline properties (permittivity and conductivity) of 17 different cell lines of several tumor types. The resulting curves were analyzed by a 2-way ANOVA. Additionally, we determined the optimal frequency for maximum cytotoxic effect for each cell line using the inovitroTM system and eventually compared with the detected electrical properties. RESULTS We found cell lines with an optimal TTFields frequency of 150 kHz (corresponding to cells with a membrane capacitance in the lower range of the observed 3DEP curves, n=9) to possess significantly different (p<0.001) electrical properties from cells with an optimal TTFields frequency of 200 kHz (n=8). According to the curve differences in the lower frequency range, the measure of membrane capacitance served as a good predictor for TTFields response. CONCLUSION This study showed a correlation of cell membrane capacitance and optimal TTFields frequency and response. Our results provide a substantial rationale for further studies investigating the predictive potential of electrical properties of tumor cells as a measure for the optimal frequency and sensitivity to TTFields in individual patients.

Structures and electrical properties of barium strontium titanate thin films grown by multi-ion-beam reactive sputtering technique

1995 ◽  
Vol 10 (3) ◽  
pp. 708-726 ◽  
Author(s):  
C-J. Peng ◽  
S.B. Krupanidhi
Keyword(s):  
Dielectric Constant ◽  
Electrical Properties ◽  
Strontium Titanate ◽  
Electric Fields ◽  
Barium Strontium Titanate ◽  
Elevated Temperatures ◽  
Ion Beam ◽  
Type I ◽  
Type Ii ◽  
Barium Strontium

The structure and electrical properties of multi-ion beam reactive sputter (MIBERS) deposited barium strontium titanate (BST) films were characterized in terms of Ba/Sr ratio, substrate temperature, annealing temperature and time, film thickness, doping concentration, and secondary low-energy oxygen ion bombardment. Films deposited onto unheated substrates, followed by annealing at 700 °C showed lower dielectric constant (<200), compared to a dielectric constant of about 560 for those deposited at elevated temperatures, probably due to reduced voids. Two types of microstructures (type I and type II) were observed depending on the incipient phase of the as-grown films, which also led to two types of time domain dielectric response, Curie-von Schweidler and Debye type, respectively. The current-voltage (I-V) characteristics of type II films doped with high donor concentration showed a bulk space-charge-limited conduction (SCLC) with discrete shallow traps embedded in a trap-distributed background at high electric fields. The I-V characteristics of bombarded films deposited at higher substrate temperatures showed promising results of lower leakage currents and trap densities.

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