Investigation of ecogeophysical factors of the environment of Vladikavkaz

A study of ecogeophysical factors of the environment in Vladikavkaz was carried out at 126 points: indicators of noise pollution, electric fields and the level of gamma radiation were measured. The noise level was determined with the help of noise and vibration meter Ekogeofizika-110A of the domestic company Oktava. It has been defined that the population of Vladikavkaz is subjected to a significant noise period of time, which exceeds the permissible level, which can negatively affect the health of citizens. Measurements of gamma radiation level were made using a gamma radiation dosimeter DBGA-OCHA. According to the obtained data, the population of Vladikavkaz is exposed to the gamma radiation in the range of 0.05–0.18 µSv/h and with an average value of 0.11 µSv/h, which is below the maximum permissible level. In order to study the electric fields, the measurements were carried out by the electric field meter IEP-05. The electric field strength reached up to 1400 V/m at individual measurement points, at an acceptable level of 800 V/m; this indicator exceeds the maximum permissible values.

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INVESTIGATION OF ECOGEOPHYSICAL AND METEOROLOGICAL FACTORS OF THE ENVIRONMENT OF VLADIKAVKAZ

Геология и геофизика Юга России ◽

10.23671/vnc.2017.3.9503 ◽

2017 ◽

Author(s):

О.Г. Бериев ◽

Т.В. Закс ◽

А.С. Кануков

Keyword(s):

Electric Field ◽

Gamma Radiation ◽

Electric Fields ◽

Air Temperature ◽

First Aid ◽

Meteorological Variables ◽

Individual Measurement ◽

Permissible Level ◽

Time Period ◽

The City

Проведено исследование экогеофизических факторов окружающей среды г. Владикавказа в 126 точках: измерены показатели шумового загрязнения, электрических полей и уровень гамма излучения. Уровень шума был измерен с помощью измерителя шума и вибрации Экогеофизика-110А отечественной фирмы Октава. Установлено, что население города Владикавказа значительный временной отрезок суток подвергается шумовому воздействию, которое превышает допустимый уровень, что может негативно влиять на здоровье горожан. Замеры уровня гамма-излучения были произведены с помощью прибора дозиметр гамма-излучения ДБГА-ОЧА. Согласно полученным данным, население города Владикавказа подвергается воздействию гамма-излучения в пределах 0,05?0,18 мкЗв / час и при средней величине 0,11 мкЗв / час, что ниже предельно допустимого уровня. Для изучения электрических полей измерения проводились измерителем электрического поля ИЭП-05. Напряженность электрического поля достигала до 1400 В / м в отдельных точках измерений, при допустимом уровне 800 В / м, превышает предельно допустимые значения. Изучено воздействие ряда метеорологических параметров (температуры воздуха и почвы, влажность воздуха, облачность, сумма осадков, продолжительность солнечного периода, направление и сила ветра) на здоровье населения города Владикавказа. Проведен анализ числа обращений на станцию Скорой помощи города за 2016 год. Полученные данные сопоставлены со сведениями Северо-Осетин- ского центра по гидрометеорологии и мониторингу окружающей среды за тот же временной период. Для статистической обработки полученных результатов применялся метод регрессионного анализа. Установ- лено, что из всех изученных метеовеличин только температура воздуха, являющаяся одним из самых метеопатических факторов, оказывает заметное влияние на частоту вызовов скорой помощи. Оценивая воздействие температуры воздуха на вызовы Скорой помощи, следует отметить вариацию корреляцион- ной зависимости ряда класса заболеваний от её изменения, что, несомненно, требует более детального изучения этой проблемы. A study was made of ecogeophysical environmental factors in Vladikavkaz at 126 points: noise pollution, electric fields and gamma radiation were measured. The noise level was measured with the help of a noise meter and vibration Ekogeofizika-110A of the domestic firm Octave. It is established that the population of the city of Vladikavkaz has a significant time period exposed to noise, which exceeds the permissible level, which can adversely affect the health of citizens. Measurements of the gamma radiation level were made with the help of the device a dosimeter of gamma radiation DBGA-OCHA. According to the received data, the population of the city of Vladikavkaz is exposed to gamma radiation within the range of 0,05?0,18 ?Sv / h and at an average value of 0,11 ?Sv / h, which is below the maximum permissible level. For the study of electric fields, the measurements were carried out by the IEP-05 electric field measurer. The parameters of the electric field parameters were up to 1400 V / m at individual measurement points with an allowable level of 800 V / m, indicating that the maximum permissible values for this indicator were exceeded. The effects of a number of meteorological variables (air and soil temperatures, air humidity, cloudiness, sum of precipitation, duration of sunshine, direction and strength of the wind) on the health of the population of the city of Vladikavkaz have been studied. The analysis of the number of calls to the city’s First Aid Station for 2016 was conducted. The obtained data are compared with the data of the North Ossetian Center for Hydrometeorology and Environmental Monitoring for the same time period. For statistical processing of the results obtained, the regression analysis method was used. It is established that of all the meteorological variables studied, only air temperature, which is one of the most meteopatic factors, has a noticeable effect on the frequency of ambulance calls. Estimating the effect of air temperature on the calls of the First Aid, it is necessary to note the variation of the correlation dependence of a number of diseases on its changes, which undoubtedly requires a more detailed study of this problem.

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Method for measuring intensity of inhomogeneous electrical fields by average value

Omsk Scientific Bulletin ◽

10.25206/1813-8225-2021-178-67-74 ◽

2021 ◽

pp. 67-74

Author(s):

S. V. Biryukov ◽

◽

L. V. Tyukina ◽

A. V. Tyukin ◽

◽

...

Keyword(s):

Field Strength ◽

Electric Field ◽

Electric Field Strength ◽

Electric Fields ◽

High Precision ◽

Measurement Method ◽

Measurement Methods ◽

New Method ◽

Average Value ◽

True Value

Measurement and control of the intensity levels of inhomogeneous electric fields with high accuracy is quite a difficult task. The solution to this problem is connected both with the development of new sensors and methods for measuring the electric field strength. The creation of new high-precision electrical induction sensors has exhausted its capabilities at the current level of technology and technology. Therefore, new ideas are needed for solving the problems of high-precision measurement of the electric field strength. One of these ways is the development of new measurement methods. Existing measurement methods characterized by the complexity of the measurement processes, suitability in some cases, and unsuitability in others, do not provide the desired metrological characteristics. Therefore, the work related to the development of methods for measuring the intensity of inhomogeneous electric fields does not stand still, and is relevant. The aim of the study is to create a new method for measuring the strength of electric fields using known sensors, which makes it possible to significantly reduce the error in measuring inhomogeneous electric fields. The idea of constructing a new measurement method is formed. The idea of the method is that in the presence of two physical quantities measured with different sign values of the error, the average value of the physical quantity will always be closer to the true value. Based on this, a new method for measuring the intensity of inhomogeneous electric fields is proposed, associated only with the original measurement process. The measurement method id named «Average value method» (MSZ). The estimation of the error of this method shows a decrease in the measurement error to +5 % with the full spatial measurement range 0a1. Using the «Average value method» it is possible to achieve a significant increase in the accuracy of measuring the strength of inhomogeneous electric fields in a wide spatial range of measurements in comparison with known methods

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A Novel Technique for Determination of Residual Direct-Current Voltage of Liquid Crystal Cells with Vertical and In-Plane Electric Fields

Symmetry ◽

10.3390/sym13050816 ◽

2021 ◽

Vol 13 (5) ◽

pp. 816

Author(s):

Msanobu Mizusaki ◽

Shoichi Ishihara

Keyword(s):

Liquid Crystal ◽

Electric Field ◽

Electric Fields ◽

Direct Current ◽

Fringe Field ◽

Average Value ◽

Novel Technique ◽

Current Voltage ◽

Direct Current Voltage ◽

Two Peaks

Generation of residual direct-current (DC) voltage (VrDC) induces serious image sticking of liquid crystal displays (LCDs). In this study, a novel technique to determine the VrDC of LC cells is proposed. We found that the VrDC could be determined from a current-voltage (I-V) curve obtained by the application of triangular voltage. In the case of a vertically aligned twisted nematic (VTN) mode LC cell, where a vertical electric field is applied, the I-V curve shows maximum and minimum current peaks owing to rotation of an LC director, and the VrDC is able to be determined from an average value of the two peaks. On the other hand, in the case of a fringe field switching (FFS) mode LC cell, where an in-plane (lateral) electric field is applied from comb electrodes, the current peaks derived from the rotation of the LC director do not appear. Therefore, we could not adopt the same way with that of the VTN mode LC cell. However, we found that there were two minimum current peaks derived from minimum capacitances of the FFS mode LC cell, and could determine the VrDC by using these two current peaks. The proposed technique would be useful for the evaluation of the VrDC of the LCDs, where the electric field is applied both vertically and laterally.

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Tuning the Electric Field Response of MOFs by Rotatable Dipolar Linkers

10.26434/chemrxiv.8153198.v1 ◽

2019 ◽

Author(s):

Johannes P. Dürholt ◽

Babak Farhadi Jahromi ◽

Rochus Schmid

Keyword(s):

Electric Field ◽

Electric Fields ◽

Structural Changes ◽

Dielectric Behavior ◽

Two Dimensions ◽

Dielectric Constants ◽

Electric Response ◽

Dipole Strength ◽

Metal Organic ◽

Dynamics Simulations

Recently the possibility of using electric fields as a further stimulus to trigger structural changes in metal-organic frameworks (MOFs) has been investigated. In general, rotatable groups or other types of mechanical motion can be driven by electric fields. In this study we demonstrate how the electric response of MOFs can be tuned by adding rotatable dipolar linkers, generating a material that exhibits paralectric behavior in two dimensions and dielectric behavior in one dimension. The suitability of four different methods to compute the relative permittivity κ by means of molecular dynamics simulations was validated. The dependency of the permittivity on temperature T and dipole strength μ was determined. It was found that the herein investigated systems exhibit a high degree of tunability and substantially larger dielectric constants as expected for MOFs in general. The temperature dependency of κ obeys the Curie-Weiss law. In addition, the influence of dipolar linkers on the electric field induced breathing behavior was investigated. With increasing dipole moment, lower field strength are required to trigger the contraction. These investigations set the stage for an application of such systems as dielectric sensors, order-disorder ferroelectrics or any scenario where movable dipolar fragments respond to external electric fields.

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Meta-Deflectors Made of Dielectric Nanohole Arrays with Anti-Damage Potential

Photonics ◽

10.3390/photonics8040107 ◽

2021 ◽

Vol 8 (4) ◽

pp. 107

Author(s):

Haichao Yu ◽

Feng Tang ◽

Jingjun Wu ◽

Zao Yi ◽

Xin Ye ◽

...

Keyword(s):

Electric Field ◽

Electric Fields ◽

Laser Cutting ◽

High Complexity ◽

Damage Potential ◽

Optical Components ◽

Nanohole Arrays ◽

Intense Light ◽

Polarization Of Light ◽

Air Hole

In intense-light systems, the traditional discrete optical components lead to high complexity and high cost. Metasurfaces, which have received increasing attention due to the ability to locally manipulate the amplitude, phase, and polarization of light, are promising for addressing this issue. In the study, a metasurface-based reflective deflector is investigated which is composed of silicon nanohole arrays that confine the strongest electric field in the air zone. Subsequently, the in-air electric field does not interact with the silicon material directly, attenuating the optothermal effect that causes laser damage. The highest reflectance of nanoholes can be above 99% while the strongest electric fields are tuned into the air zone. One presentative deflector is designed based on these nanoholes with in-air-hole field confinement and anti-damage potential. The 1st order of the meta-deflector has the highest reflectance of 55.74%, and the reflectance sum of all the orders of the meta-deflector is 92.38%. The optothermal simulations show that the meta-deflector can theoretically handle a maximum laser density of 0.24 W/µm2. The study provides an approach to improving the anti-damage property of the reflective phase-control metasurfaces for intense-light systems, which can be exploited in many applications, such as laser scalpels, laser cutting devices, etc.

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Integrating flexible electronics for pulsed electric field delivery in a vascularized 3D glioblastoma model

npj Flexible Electronics ◽

10.1038/s41528-021-00115-x ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

Marie C. Lefevre ◽

Gerwin Dijk ◽

Attila Kaszas ◽

Martin Baca ◽

David Moreau ◽

...

Keyword(s):

Electric Field ◽

Electric Fields ◽

Flexible Electronics ◽

Soft Tissues ◽

Multiphoton Microscopy ◽

Membrane Integrity ◽

Tumor Model ◽

Pulsed Electric Fields ◽

In Ovo ◽

Cell Membrane Integrity

AbstractGlioblastoma is a highly aggressive brain tumor, very invasive and thus difficult to eradicate with standard oncology therapies. Bioelectric treatments based on pulsed electric fields have proven to be a successful method to treat cancerous tissues. However, they rely on stiff electrodes, which cause acute and chronic injuries, especially in soft tissues like the brain. Here we demonstrate the feasibility of delivering pulsed electric fields with flexible electronics using an in ovo vascularized tumor model. We show with fluorescence widefield and multiphoton microscopy that pulsed electric fields induce vasoconstriction of blood vessels and evoke calcium signals in vascularized glioblastoma spheroids stably expressing a genetically encoded fluorescence reporter. Simulations of the electric field delivery are compared with the measured influence of electric field effects on cell membrane integrity in exposed tumor cells. Our results confirm the feasibility of flexible electronics as a means of delivering intense pulsed electric fields to tumors in an intravital 3D vascularized model of human glioblastoma.

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Electro-Optic Control of Lithium Niobate Bulk Whispering Gallery Resonators: Analysis of the Distribution of Externally Applied Electric Fields

Crystals ◽

10.3390/cryst11030298 ◽

2021 ◽

Vol 11 (3) ◽

pp. 298

Author(s):

Yannick Minet ◽

Hans Zappe ◽

Ingo Breunig ◽

Karsten Buse

Keyword(s):

Lithium Niobate ◽

Electric Field ◽

Electric Fields ◽

Frequency Comb ◽

Parametric Oscillation ◽

Pockels Effect ◽

Optical Mode ◽

Cylindrical Resonator ◽

Whispering Gallery ◽

Electro Optic

Whispering gallery resonators made out of lithium niobate allow for optical parametric oscillation and frequency comb generation employing the outstanding second-order nonlinear-optical properties of this material. An important knob to tune and control these processes is, e.g., the linear electro-optic effect, the Pockels effect via externally applied electric fields. Due to the shape of the resonators a precise prediction of the electric field strength that affects the optical mode is non-trivial. Here, we study the average strength of the electric field in z-direction in the region of the optical mode for different configurations and geometries of lithium niobate whispering gallery resonators with the help of the finite element method. We find that in some configurations almost 100% is present in the cavity compared to the ideal case of a cylindrical resonator. Even in the case of a few-mode resonator with a very thin rim we find a strength of 90%. Our results give useful design considerations for future arrangements that may benefit from the strong electro-optic effect in bulk whispering gallery resonators made out of lithium niobate.

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Double layers in the downward current region of the aurora

Nonlinear Processes in Geophysics ◽

10.5194/npg-10-45-2003 ◽

2003 ◽

Vol 10 (1/2) ◽

pp. 45-52 ◽

Cited By ~ 32

Author(s):

R. E. Ergun ◽

L. Andersson ◽

C. W. Carlson ◽

D. L. Newman ◽

M. V. Goldman

Keyword(s):

Magnetic Field ◽

Electron Beam ◽

Phase Space ◽

Electric Field ◽

Electric Fields ◽

Double Layers ◽

Parallel Electric Field ◽

Electrostatic Waves ◽

Current Region ◽

Decisive Evidence

Abstract. Direct observations of magnetic-field-aligned (parallel) electric fields in the downward current region of the aurora provide decisive evidence of naturally occurring double layers. We report measurements of parallel electric fields, electron fluxes and ion fluxes related to double layers that are responsible for particle acceleration. The observations suggest that parallel electric fields organize into a structure of three distinct, narrowly-confined regions along the magnetic field (B). In the "ramp" region, the measured parallel electric field forms a nearly-monotonic potential ramp that is localized to ~ 10 Debye lengths along B. The ramp is moving parallel to B at the ion acoustic speed (vs) and in the same direction as the accelerated electrons. On the high-potential side of the ramp, in the "beam" region, an unstable electron beam is seen for roughly another 10 Debye lengths along B. The electron beam is rapidly stabilized by intense electrostatic waves and nonlinear structures interpreted as electron phase-space holes. The "wave" region is physically separated from the ramp by the beam region. Numerical simulations reproduce a similar ramp structure, beam region, electrostatic turbulence region and plasma characteristics as seen in the observations. These results suggest that large double layers can account for the parallel electric field in the downward current region and that intense electrostatic turbulence rapidly stabilizes the accelerated electron distributions. These results also demonstrate that parallel electric fields are directly associated with the generation of large-amplitude electron phase-space holes and plasma waves.

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Clarifications on the Behavior of Alternative Gases to SF6 in Divergent Electric Field Distributions under AC Voltage

Energies ◽

10.3390/en14041065 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1065

Author(s):

Houssem Eddine Nechmi ◽

Michail Michelarakis ◽

Abderrahmane (Manu) Haddad ◽

Gordon Wilson

Keyword(s):

Electric Field ◽

Electric Fields ◽

Partial Discharge ◽

Mean Value ◽

Electrode System ◽

Polarity Reversal ◽

Buffer Gas ◽

Co2 Gas ◽

Breakdown Mechanism ◽

Positive Cycle

Negative and positive partial discharge inception voltages and breakdown measurements are reported in a needle-plane electrode system as a function of pressure under AC voltage for natural gases (N2, CO2, and O2/CO2), pure NovecTM gases (C4F7N and C5F10O) and NovecTM in different natural gas admixtures. For compressed 4% C4F7N–96% CO2 and 6% C5F10O–12% O2–82% CO2 gas mixtures, the positive-streamer mode is identified as the breakdown mechanism. Breakdown and negative partial discharge inception voltages of 6% C5F10O–12% O2–82% CO2 are higher than those of 4% C4F7N–96% CO2. At 8.8 bar abs, the breakdown voltage of 6% C5F10O–12% O2–82% CO2 is equal to that of 12.77% O2–87.23% CO2 (buffer gas). Synergism in negative partial discharge inception voltage/electric field fits with the mean value and the sum of each partial pressure individually component for a 20% C4F7N–80% CO2 and 6% C5F10O–12% O2–82% CO2, respectively. In 9% C4F7N–91% CO2, the comparison of partial discharge inception electric fields is Emax (CO2) = Emax(C4F7N), and Emax (12.77% O2–87.23% CO2) = Emax(C5F10O) in 19% C5F10O–81%(12.77% O2–87.23% CO2). Polarity reversal occurs under AC voltage when the breakdown polarity changes from negative to positive cycle. Polarity reversal electric field EPR was quantified. Fitting results show that EPR (CO2) = EPR(9% C4F7N–91% CO2) and EPR(SF6) = EPR (22% C4F7N–78% CO2). EPR (4% C4F7N–96% CO2) = EPR (12.77% O2–87.23% CO2) and EPR (6% C5F10O–12% O2–82% CO2) < EPR (4% C4F7N–96% CO2) < EPR (CO2).

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Tuning Single-Molecule Conductance by Controlled Electric Field-Induced trans-to-cis Isomerisation

Applied Sciences ◽

10.3390/app11083317 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3317

Author(s):

C.S. Quintans ◽

Denis Andrienko ◽

Katrin F. Domke ◽

Daniel Aravena ◽

Sangho Koo ◽

...

Keyword(s):

Electric Field ◽

Electric Fields ◽

Single Molecule ◽

Quantum Interference ◽

Single Molecule Level ◽

Wet Chemical Synthesis ◽

Single Molecule Junctions ◽

Tunnelling Microscopy ◽

The Difference

External electric fields (EEFs) have proven to be very efficient in catalysing chemical reactions, even those inaccessible via wet-chemical synthesis. At the single-molecule level, oriented EEFs have been successfully used to promote in situ single-molecule reactions in the absence of chemical catalysts. Here, we elucidate the effect of an EEFs on the structure and conductance of a molecular junction. Employing scanning tunnelling microscopy break junction (STM-BJ) experiments, we form and electrically characterize single-molecule junctions of two tetramethyl carotene isomers. Two discrete conductance signatures show up more prominently at low and high applied voltages which are univocally ascribed to the trans and cis isomers of the carotenoid, respectively. The difference in conductance between both cis-/trans- isomers is in concordance with previous predictions considering π-quantum interference due to the presence of a single gauche defect in the trans isomer. Electronic structure calculations suggest that the electric field polarizes the molecule and mixes the excited states. The mixed states have a (spectroscopically) allowed transition and, therefore, can both promote the cis-isomerization of the molecule and participate in electron transport. Our work opens new routes for the in situ control of isomerisation reactions in single-molecule contacts.

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