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The drying of compact and biologically active materials presents significant challenges. In this study, we propose using electrostatic field–ultrasonic coupling pretreatment to enhance the drying efficiency of ginkgo fruits. We designed and constructed an experimental device to investigate the effects of ultrasonic power, pretreatment time, hot air drying temperature, and electrostatic field voltage on the moisture content of the fruits. We used the response surface methodology to identify optimal process conditions and further explored the kinetic model for the moisture content of the fruits under the pretreatment. The results showed that the optimal process parameters for electrostatic–ultrasound pretreatment and the drying of ginkgo fruits were: an electrostatic field voltage of 11.252 kV, an ultrasound power of 590.074 W, a pretreatment time of 32.799 min, and a hot air drying temperature of 85 °C. Under the optimized process conditions, the correlation between the moisture content of ginkgo fruits and the two-term drying kinetics model was the highest. After electrostatic–ultrasound coupling pretreatment, the drying rate of ginkgo fruits was significantly improved during hot air drying.

The aim of this paper was to examine the influence of the electrostatic field on seeds of soybean (Glycine max L), vetch (Vicia spp. L.), pea (Pisum sativum L.), grass pea (Lathyrus sativus L.) and chickpea (Cicer arietinum L.) which were selected at the Institute of Field and Vegetable Crops in Novi Sad. The DC voltage of 9V was used. The durations of seed treatment were 0 (control), 1, 2 and 3 minutes. The trial was set up as a randomized block design with four replications. 4x100 seeds of each variant and control (untreated seed) were treated. After treatment, seed quality was examined using a germination test (optimal temperature) and a cold test (low temperature). The results of the study showed that the effect of the electrostatic field on seed quality depended on the plant species, the time of seed treatment and the temperature conditions in which the seed germinated after treatment. The increase in germination energy ranged up to 18.18% in vetch, and a decrease of up to 12% was observed in chickpea. The application of the electrostatic field had a significantly greater impact on seeds that were exposed to low temperatures in the germination process after treatment. The increase in seed germination ranged up to 82.35% in chickpeas, and the decrease amounted to 92.68% in peas. In addition, the obtained results indicate that it is not possible to talk about the universal application of a certain duration of seed treatment. Cilj rada je bio ispitivanje uticaja elektrostatičkog polja na seme soje (Glycine max L.), grahorice (Vicia spp. L.), graška (Pisum sativum L.), sastrice (Lathyrus sativus L.) i nauta (Cicer arietinum L.) koji su selekcionisani na Institutu za ratarstvo i povrtarstvo u Novom Sadu. Za tretiranje je korišćen jednosmerni napon jačine 9 V. Vreme tretiranja semena iznosilo je 0 (kontrola), 1, 2 i 3 minuta. Nakon tretiranja, ispitan je kvalitet semena primenom standardnog testa klijavosti (optimalna temperatura) i hladnog testa (niska temperatura). Rezultati istraživanja su pokazali da je efekat elektrostatičkog polja na kvalitet semena zavisio od biljne vrste, vremena tretiranja semena i temperaturnih uslova u kojima je seme klijalo nakon tretiranja. Povećanje energije klijanja se kretalo do 18,18% kod grahorice, a smanjenje do 12% kod nauta. Značajno veći uticaj primena elektrostatičkog polja imala je na semenu koje je posle tretiranja izloženo niskoj temperaturi u procesu klijanja. Povećanje klijavosti semena se kretalo do 82,35% kod nauta, a smanjenje do 92,68% kod graška. Takođe, dobijeni rezultati ukazuju na to da se ne može govoriti o univerzalnoj primeni određenog vremena tretiranja, jer se može dogoditi da ono ne odgovara određenoj biljnoj vrsti, pa može doći do pogoršanja kvaliteta semena.

The gross charge distribution in an electrified cloud has already been estimated by polarity distribution of the electrostatic field on the ground surface. While either a dipole or a tripole charge structure is commonly accepted, the increase–decrease and motion of each point charge in those models are both still unclear. This paper presents a new network of electric field mills for multipoint electrostatic measurement to evaluate the temporal variations of a simple cloud charge model with second-scale resolution. Details of our newly developed equipment are described, with an emphasis on its advantages. This network was deployed in the north Kanto area of Japan and operated during the summer season in 2020. In order to simplify the relationship between cloud charge positions and the horizontal distribution of the measured electrostatic field, an isolated thundercloud is focused on. As an initial analysis, a negative point charge model is applied to an isolated cloud observed on 27 August 2020. The quantity and height of the point charge were estimated as being approximately −20 C and 7 km, respectively. The calculated charge location is generally coincident with the C-band radar echo regions. Significant correspondence is demonstrated between the intensity distribution of the electrostatic fields measured at seven sites and that calculated with estimated point charge. This result indicates the possibility to determine the amounts and positions of cloud charges inside the dipole charge structure based on multipoint measurement of the electrostatic field.

In this study, we simulated the electron density disturbance at night in the bottom of the ionosphere caused by the electrostatic field in a thundercloud. The simulation was conducted using the charge of the thundercloud as the source, by incorporating a more up-to-date conductivity profile, and using the ion chemistry model for the lower ionosphere. The results revealed that a thundercloud charge of 30–100 C can cause a disturbance in the electron density in the lower ionosphere, decreasing to 40% of the original value or increasing to 160% of the original value. The electron density disturbance occurs mainly below an altitude of 80 km, and its peak is located at an altitude of 70 km, with a regional horizontal radius of about 50–75 km. The simulation results of this study improve the theory of Salem et al and extend the original one-dimensional model to three-dimensional space.

The complex effect of two factors (the optimum ratio of nutrients of the medium and the electrostatic field) on the qualitative and quantitative indicators of Chlorella vulgaris was investigated. It is shown that the use of a medium with optimal concentrations of mineral substances and an electrostatic field with a voltage of 15 kV and an exposure time of 72 hours has a positive effect on growth rates, the size of microalgae cells and their viability, contributes to obtaining a culture with a density of 50 mln cells / ml 18 hours faster in comparison with the cultivation of generally accepted methods. It has been established that when two factors are influences on the cells of the Chlorella a mutagenic effect is not observed. Analysis of the microalgae culture grown under the influence of the studied factors showed that its chemical composition was consistent and with several indicators exceeded that of chlorella cultivation according to classical technologies. It was revealed that the activity of catalase and superoxide dismutase of microalgae grown in optimal conditions of the nutrient medium and the electrostatic field, significantly exceeded similar values of Chlorella vulgaris, which was not subjected to electrostatic stimulation. The high activity of the studied enzymes in Chlorella cells is shown in comparison with higher plants – components of bio-antioxidant preparations, such as Amaranthus paniculatus L. and Nicotiana tabacum L. According to the results of the toxicological study the absence of the content in Chlorella of the main poisonous substances for body animals and humans (mercury, arsenic) has been established. As a result of the research, it was proposed to use the established optimal parameters of both factors in the cultivation of C. vulgaris., Исследовано комплексное влияние двух факторов (оптимального соотношения питательных веществ среды и электростатического поля) на качественные и количественные показатели Chlorella vulgaris. Показано, что применение среды с оптимальными концентрациями минеральных веществ и электростатического поля с напряжением 15 кВ и временем воздействия 72 ч положительно влияют на ростовые показатели, размер клеток микроводоросли и их жизнеспособность, способствует получению культуры с плотностью 50 млн кл./мл на 18 ч быстрее в сравнении с культивированием по общепринятым методикам. Установлено, что при воздействии двух изучаемых факторов на клетки Chlorella мутагенный эффект не наблюдается. Анализ культуры микроводоросли, выращенной при воздействии исследуемых факторов, показал, что ее химический состав соответствовал и по ряду показателей превосходил таковой при культивировании хлореллы по классическим технологиям. Выявлено, что показатели активности каталазы и супероксиддисмутазы микроводоросли, выращенной в оптимальных условиях питательной среды и электростатического поля, достоверно превышали аналогичные значения C. vulgaris, не подвергавшейся стимулированию электростатическим полем. Показана большая активность исследуемых ферментов в клетках хлореллы по сравнению с высшими растениями – компонентами биоантиоксидантных препаратов, такими как Amaranthus paniculatus L. и Nicotiana tabacum L. По результатам токсикологического исследования установлено отсутствие содержания в Chlorella основных отравляющих организм животных и человека веществ (ртуть, мышьяк). В результате проведенных исследований предложено использование установленных оптимальных параметров обеих факторов в культивировании C. vulgaris.

The electrostatic field in the space excited by a thunderstorm cloud reflects the trend of the spatial potential and has a great influence on the selection of lightning discharge paths. Some studies have used an approximate method to calculate the electrostatic field excited by a thunderstorm cloud, but the error is still relatively large. In order to improve the computational accuracy, the second-order approximate solution of the electric field is obtained in this paper by using a binomial expansion of the complex quantized function, discarding the higher-order small terms and integrating the main term according to the convergence of the function. The first-order approximate solution and the second-order approximate solution are used to calculate the electrostatic field excited by a thunderstorm cloud using the same version of MATLAB on the same configuration of computers. By comparison, it is found that the computation time using the two approximate solutions is not much different, but the error between the second-order approximate solution and the exact solution is significantly smaller than that between the first-order approximate solution and the exact solution. It is shown that using the second-order approximate solution to calculate the electrostatic field of a thunderstorm cloud can greatly improve the computational accuracy without sacrificing the computational efficiency, which is of great significance for the accurate warning when lightning is approaching.

In traditional physics research, people regard electric field forces and gravity, as two completely different forces. However, after the study of the ternary equilibrium system through the law of ternary equilibrium, it is found that these two action forces actually have a certain correlation. And how are the electric field force and gravity formed? And what is the nature of these two acting forces? However, two problems are difficult to solve in the field of traditional physics. Today we will use this paper to reveal two problems difficult to solve in both traditional physics. (There may be many translation errors when the English version is converted by translation software。)

In traditional physics research, people regard electric field forces and gravity, as two completely different forces. However, after the study of the ternary equilibrium system through the law of ternary equilibrium, it is found that these two action forces actually have a certain correlation. And how are the electric field force and gravity formed? And what is the nature of these two acting forces? However, two problems are difficult to solve in the field of traditional physics. Today we will use this paper to reveal two problems difficult to solve in both traditional physics. (There may be many translation errors when the English version is converted by translation software。)

A number of international, European Union and Latvian legislative acts have been developed, which regulate the efficiency of gas combustion plants and greenhouse gas emissions in the atmosphere. These legislative acts require the development of new scientifically efficient methods for gas optimal combustion with a minor impact on the environment. In order to achieve such a goal, different methods can be used, but the most efficient is an intensive electrostatic field application to control combustion and harmful emission formation in premixed flames. In the framework of the current study, the authors developed a hybrid burner, which allowed generating an intensive electrostatic field with intensity of more than 1000 kV/m. The study also investigated the impact of such a field on the formation of harmful emissions, including CO2 and flue gas temperature. The empirical results showed that an intensive DC electrostatic field generated inside of the burner had an impact on the flame shape, CO2, NOx emissions and flue gas temperature. In its turn, by applying an intensive pulsating electrostatic field (multivariable experiment) it was possible to achieve the reduction in NOx, CO emissions with a simultaneous increase in flue gas temperature, which was related to combustion process efficiency enhancement.

In order to reveal the process of insulation destruction of circuit breaker in GIS under lightning impulse voltage, a new method of transient insulation numerical analysis is described in this paper. A combination of the electromagnetic transient analysis method and optimised charge simulation method (CSM) was put forward to calculate and analyse the transient insulation characteristics of 550 kV circuit breaker in GIS under lightning impulse voltage. The results show that, within 0–15 μ, though the voltage of circuit breaker did not reach its peak, there is severe electric field distortion caused by sharp change of voltage with a high probability of circuit breaker insulation breakdown. In addition, as for the circuit breaker insulation structure optimisation design, it is advisable to restrain the change rate of electric field strength amplitude so as to reduce the probability of insulation breakdown, rather than simply verify insulation structure by using maxi-mum electric field strength as the voltage input parameters of the electrostatic field under the power frequency in accordance with the traditional insulation analysis method, with the purpose of ensuring the circuit breaker can operate safely and reliably for a long time.

В настоящее время совершенствование процессов послеуборочной обработки зернобобовых культур является актуальной задачей для предприятий агропромышленного комплекса. Вопросы, связанные с интенсификацией известных способов надежной защиты зернобобовых культур от воздействия патогенной микрофлоры, а также карантинных насекомых-вредителей, вызывают предметный интерес для исследования. В статье предложен способ автоматического управления процессом электростатической фумигации семян зернобобовых культур в установке барабанного типа, который обеспечивает повышение производительности оборудования благодаря согласованной работе генератора аэродисперсной смеси (фумигирующего газа с воздухом), камеры ионизации и фумига- ционной камеры, а также способствует снижению удельных энергетических затрат за счет поддержания наиболее рациональных условий протекания процесса фумигации., Currently improving the processes of post-harvest processing of leguminous crops is an urgent task for enterprises of the agro-industrial complex. Issues related to the intensification of methods of reliable protection of legumes from the effects of pathogenic microflora, as well as quarantine insect pests, are of substantive interest for research. The article proposes a method for automatic control of the process of electrostatic fumigation of seeds of leguminous crops in a drum-type installation, which provides an increase in the productivity of equipment due to the coordinated operation of the generator of aero -dispersed mixture (fumigating gas with air), an ionization chamber and a fumigation chamber, and also helps to reduce specific energy costs maintaining the most rational conditions for the fumigation process.

Electrospinning is an experimental method of the polymer super thin fibres formation using the electrostatic field. The distribution of electrostatic field affects the effectiveness of the electrospinning. In order to analyse the electrostatic field for given technological parameters the 3-D computer model of an electrospinning device must be applied.

The world's perennial need for energy and microelectronic miniaturization brings with it a broad set of technological and scientific challenges. Materials characterized by precise microstructural architectures based on fractal analysis and ranging in size down to nano scale represent an important avenue for finding novel solutions. Deep materials structure hierarchies of this type open new possibilities in capacity according to the Heywang model, especially when extended by a fractals approach and intergranular relationships supported and recognized by their fractal nature. These developments are opening new frontiers in microelectronics miniaturization. They build on early fractal applications that were used as tools in miniaturization research and also provided application perspectives for diverse energy technologies. In other words, fractals, as a crucial concept of modern theoretical-experimental physics and materials sciences, are tightly linked to higher integration processes and microelectronics miniaturization. They also hold potential for meeting the energy exploitation challenge. In this research context, for the first time we experimentally and theoretically investigated the electrostatic field between the grains within fractal nature aspects. It is essentially a theoretical experiment based on samples of experimental microstructures imaged with SEM, as previously published in a number of other papers. We now take the research a step further by consolidating the experimental samples with respect to the predicted distribution of grains and pores within the sample mass. We make an original contribution by opening the frame of scale sizes with respect to the technical processes of consolidation. This lets us predict the constitutive elements of the microstructures – approximately equidistant grains and pores. In this paper we define in a practical manner the final target elements for experimental consolidation of real samples. It is the main bridge between a designed microstructure and related characteristics – for example, fractal dimensions and final properties of next-generation fractal microelectronics. Peer-reviewed manuscript: [https://hdl.handle.net/21.15107/rcub_dais_4795]

This paper presents the basic concepts regarding the electrostatic effect of the electrical transport lines on the electrical lines located on the same electrical support pillar. The influence of the electrical transport lines on the neighbouring lines can be: electrostatic, given by the electrostatic field and electromagnetic, given by the electromagnetic field. Depending on the position and the configuration of the electrical lines, the induced voltages and the electric field can be calculated analytically or numerically (by using the Quick Field application).Two configurations are analysed analytically: inductor line – one-wired induced line and one-wired inductor line – two-wired induced line. The graphical results (the electrical potential and the electrical field of the one-wired inductor line and one-wired induced line) of the experimental simulations (inductor line – one-wired induced line and one-wired inductor line) are presented in the Quick Field application.

The effect of electrostatic fields on the bioelectrochemical removal of ammonium and nitrite from nitrogen-rich wastewater was investigated at strengths ranging from 0.2 to 0.67 V/cm in bioelectrochemical anaerobic batch reactors. The electrostatic field enriched the bulk solution with electroactive bacteria, including ammonium oxidizing exoelectrogens (AOE) and denitritating electrotrophs (DNE). The electroactive bacteria removed ammonium and nitrite simultaneously with alkalinity consumption through biological direct interspecies electron transfer (DIET) in the bulk solution. However, the total nitrogen (ammonium and nitrite) removal rate increased from 106.1 to 166.3 mg N/g volatile suspended solids (VSS).d as the electrostatic field strength increased from 0.2 to 0.67 V/cm. In the cyclic voltammogram, the redox peaks corresponding to the activities of AOE and DNE increased as the strength of the electrostatic field increased. Based on the microbial taxonomic profiling, the dominant genera involved in the bioelectrochemical nitrogen removal were identified as Pseudomonas, Petrimonas, DQ677001_g, Thiopseudomonas, Lentimicrobium, and Porphyromonadaceae_uc. This suggests that the electrostatic field of 0.67 V/cm significantly improves the bioelectrochemical nitrogen removal by enriching the bulk solution with AOE and DNE and promoting the biological DIET between them.

This paper presents an investigation on the enhancement of electrical insulations of power cables materials using a new multi-nanoparticles technique. It has been studied the effect of adding specified types and concentrations of nanoparticles to polymeric materials such as PVC for controlling on electric and dielectric performance. Prediction of effective dielectric constant has been done for the new nanocomposites based on Interphase Power Law (IPL) model. The multi-nanoparticles technique has been succeeded for enhancing electric and dielectric performance of power cables insulation compared with adding individual nanoparticles. Finally, it has been investigated on electric field distribution in the new proposed modern insulations for three-phase core belted power cables. This research has focused on studying development of PVC nanocomposite materials performance with electric field distribution superior to the unfilled matrix, and has stressed particularly the effect of filler volume fraction on the electric field distribution.

Phosphoinositides (PIPs) are one kind of membrane components functioning in many intracellular processes, especially in signaling transduction and membrane transport. Phosphatidylinositide phosphatases (PIPases) are specifically important for the PIP homeostasis in cell. In our previous study, we have identified the actin-related protein CaSac1 in Candida albicans, while its functional mechanisms in regulating membrane homeostasis has not been identified. Here, we show that the PIPase CaSac1 is a main membrane-related protein and regulates hyphal polarization by governing phosphoinositide dynamic and plasma membrane (PM) electrostatic field. Deletion of CaSAC1 resulted in large-scale abnormal redistribution of phosphatidylinositide 4-phosphate (PI4P) from the endomembrane to the PM. This abnormality further led to disturbance of the PM's negative electrostatic field and abnormally spotted distribution of phosphatidylinositide 4,5-bisphosphate (PI(4,5)P2). These changes led to a severe defect in polarized hyphal growth, which could be diminished with recovery of the PM's negative electrostatic field by the anionic polymer polyacrylic acid (PAA). This study revealed that the PIPase CaSac1 plays an essential role in regulating membrane homeostasis and membrane traffic, contributing to establishment of polarized hyphal growth.

This paper proposes a deployment algorithm based on the electrostatic field theory for mobile wireless sensor networks. The nodes and obstacles in the deployment area are taken as the charged particles; and the particles will move due to the Coulomb’s force from other particles or obstacles. Finally, the nodes automatically spread to the whole area by the resultant action and complete the deployment. Four metrics, including coverage, uniformity, deployment time and average displacement distance, are used to evaluate the performance of the algorithm. The simulation results show that the proposed algorithm can give full play to its self-adaptive advantages and achieve the desired deployment effect; it is a kind of deployment algorithm with self-adaptive characteristics.

We evaluated the application-oriented suitability of electrostatic fields and laser-induced discharges to enhance both debris removal and ablation rate during ultrashort pulse laser drilling of copper. The electric field was varied to either induce or prevent laser-induced electric discharges. Results show that debris is expelled to a much greater distance by applying an electric field. If a laser-induced electric discharge is induced, greater heat-affected zone and greater amounts of debris are observed, pointing to an increased amount of ablated material. Results were independent on the applied voltage polarity, suggesting that there is no significant charge separation in the material plasma.

In order to study the inactivation effects of electrostatic field of electret films on Bacillus subtilis , a plane–plane electrode system was used to simulate the electric field of the electret films and the viability of B. subtilis affected by electrostatic field for different applying durations was investigated. It was found that the survival ratio of B. subtilis can be considerably affected by the field and duration. It was also found that the viability of bacillus decreases with the increase of the duration. In addition, the comparative survival ratio (CSR) of B. subtilis decreases to 35% even during a short duration as the applied field reaches an enough high value of more than 15 kV/cm. These indicated that the uniform field inactivated the viability of B. subtilis availability. Based on the inactivation effect of the applied field on the B. subtilis , the effectiveness of charged polypropylene films on the inactivation of B. subtilis was measured and discussed.

In this paper the potential and electric field distribution in the surroundings of the cargo vehicles is approximately numerically determined, when they are exposed to the Atmospheric Electric Field (AEF), having uniform intensity and vertical polarization. The cases of the cargo vehicles either isolated or near by petrol pumps are observed. Several results of total induced charge and electrical moment of the vehicle including maps of equipotential and equienergetic curves are presented. The Equivalent Electrode Method (EEM) is used to solve this problem.

Electric field and potential distribution in the surroundings of cube electrodes are numerically determined using Equivalent Electrodes Method.

The goal of this paper is to investigate the correlation between electrostatic field of Video Display Units (VDU’ s) generated around human head located in front of VDU and related display size. The mathematical model is based on the Laplace equation for the electrostatic potential, and corresponding finite element solution. The electrostatic field is calculated for different sizes of display and for different distances between display and the human head, respectively. The results were compared with the results obtained by the finite difference method (FDM). The advantage of the presented finite element solution is a high resolution and a higher accuracy, compared to the FDM results.

The goal of this paper is to investigate interaction between electrostatic field of Video Display Units (VDU’ s) and human head in front of it. Special attention is given to the field at the surface of the face. The finite element model for assessment of the electrostatic field, by solving Laplace equation for the electric potential, is implemented. The electrostatic field is calculated for two different faces and for two different types of the domain and then compared with results obtained by the finite difference method. The advantage of the presented numerical method is a high resolution and a higher accuracy.

Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2003, Thesis (PhD) -- İstanbul Technical University, Institute of Science and Technology, 2003, Bu çalışmada, yük benzetim yöntemi ile gazlarda, elektrostatik alan dağılımı ve korona başlangıç geriliminin hesabı için Windows işletim sisteminde çalışan, Korona 2002 adı verilen bir yazılım geliştirilmiştir. Geliştirilen yazılımla çubuk-düzlem, küre-düzlem ve silindir-düzlem elektrot sistemlerinde alan dağılımı ve korona başlangıç gerilimi hesabı yapılmıştır. Korona 2002’de, elektrot geometrisi, uygulanan gerilim ve yüklerle ilgili veriler girildikten sonra, yük değerleri ve elektrot sınırında alınan kontrol noktalarında potansiyel ve elektrik alan hesaplanmaktadır. Benzetimin doğruluğu, kontrol noktalarında hesaplanan potansiyellerin elektrot potansiyeline yakınlığı ile belirlenmektedir. Yeterli doğruluk elde edilmişse, elektrostatik alan dağılımı çizdirilmekte, maksimum elektrik alan şiddeti, faydalanma faktörü ve iyonlaşma bölgesi hesaplanmaktadır. Daha sonra, korona başlangıç gerilimini hesaplamak amacıyla, elektron çığının benzetimi halkasal yüklerle yapılmaktadır. Halkasal yükün değeri, elektronlarla gaz atomlarının çarpışma noktalarında oluşan pozitif iyonların toplam yüküne eşit alınmakta, yarıçapları ise elektronun difüzyon yarıçapından hesaplanmaktadır. Elektron çığı anoda ulaştığında eğer elektron sayısı 108 adet olursa, bu durumda çubuk ucundaki maksimum elektrik alanı 24.4 kV’tan küçük olmaktadır. Bu koşul sağlanırsa korona başlamış kabul edilmektedir. Bu durumda uygulanan gerilim korona başlangıç gerilimidir. Yapılan uygulamada, korona başlangıç geriliminin, korona başlangıcındaki maksimum alan şiddetinin, faydalanma faktörünün ve iyonlaşma bölgesi uzunluğunun, sabit elektrot yarıçapında elektrot açıklığı ile değişimi ve sabit elektrot açıklığında elektrot yarıçapı ile değişimi incelenmiştir. Korona 2002’de düzlem elektrot, yarıçapı ve yüksekliği değiştirilebilen sonlu düzlem olarak alınabilmekte, düzlem üzerine yarıküresel pürüz yerleştirilebilmektedir. Böylece düzlemin sonlu olmasının ve/veya pürüzün etkisi incelenebilmektedir. Sonuçlar, literatürdeki çalışmalarla karşılaştırıldığında, sonuçlar arasında uyum olduğu gözlenmiştir. Korona 2002’nin, yüksek gerilimde, elektrostatik alan ve korona başlangıç gerilimi hesabında kullanılabileceği görülmüştür., High voltage equipment is the backbone of modern power systems. So, the insulation of the high voltage conductor is of primary importance. For the proper design, safe and reliable operation of the insulation system, a complete knowledge of the electric field distribution and corona inception voltage of any high voltage device is required. In the investigations of electrical breakdown of gases, particularly in the study of corona phenomena in atmospheric air, the asymmetrical nonuniform field configuration has been a valuable tool for experimental observations due to the local confinement of prebreakdown ionization around the stressed electrode. Many of the basic breakdown studies were carried out with rod to plane electrodes or with two rods. In this study, the electric field distribution and corona inception voltage of the rod-plane, sphere-plane and wire-plane electrode systems have been computed using Charge Simulation Method. A new software, named Corona 2002 (Electrical Discharge Analysis System) has been developed based on the Charge Simulation Method. Computations have been made under positive DC voltage for various electrode radius and gap spacings. In the computation of corona inception voltage, positive ions (space charges) the primary electron avalanche, have been simulated by a number of ring charges. Corona 2002, has been developed using Microsoft Visual Basic 6.0 for Windows operating system, and is user friendly. Results have been compared with those found in the literature, and were in good agreement. Results show that, Corona 2002 can safely be used to compute the electrostatic field distribution and corona inception voltage of the above mentioned electrode systems., Doktora, PhD

Molecular dynamics calculations have been carried out on a model of the LS3 synthetic ion channel in a membrane mimetic environment. In the absence of an external electrostatic field, the LS3 channel, which consists of a bundle of six α-helices with sequence Ac-(LSSLLSL)3-CONH2, exhibits large structural fluctuations. However, in the presence of the field, the bundle adopts a well defined coiled-coil structure with an inner pore of water. The observed structural changes induced by the applied field are consistent with the proposed gating mechanism of the ion channel.

The efficiency of the secondary electron detector in the scanning electron microscope (SEM) is one of the most important factors affecting the imaging process of the SEM. To compute the detector efficiency, the electrostatic field inside a specimen chamber must be known. A simple way of performing such calculations is to use a spreadsheet program which has a built-in capability of storing and performing some operations on three-dimensional matrices. Using a spreadsheet program makes it possible to solve the Laplace equation and calculate electron trajectories in geometrically complex electrostatic fields. This technique is applied to the estimation of detector efficiency in the SEM.

The numerical solution of three-dimensional electrostatic field problems in electron-optical devices with complicated boundaries requires the use of very large and fast computers. A numerical counterpart of the Alternating Procedure by H. A. Schwarz (SAP) makes efficient use of both storage space and time available on the computer and therefore represents a useful new method in this context. In this method. the domain of solution is decomposed into independent subdomains where the appropriate individual methods of solution may be chosen. Correspondingly. the original boundary value problem is decomposed into a sequence of boundary value problems in these subdomains. SAP requires no explicit influence matrix and uses little storage space. Time requirements depend essentially on the methods applied in the respective subregions. SAP is particularly useful in obtaining analytical formulas for field distributions in "large" regions of empty space (such as in fringe field regions). Numerical results obtained with a computer program treating an electrostatic quadrupole lens problem show that a high degree of accuracy can be obtained with this method.