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A stochastic method is developed, implemented and investigated here for solving Laplace, Poisson's, and standard parabolic wave equations. This method is based on the properties of random walk, diffusion process, Ito formula, Dynkin formula and Monte Carlo simulations. The developed method is a local method i:e: it gives the value of the solution directly at an arbitrary point rather than extracting its value from complete field solution and thus is inherently parallel. Field computation by this method is demonstrated for electrostatic and electrodynamic propagation problems by considering simple examples and numerical results are presented to validate this method. Numerical investigations are carried out to understand efficacy and limitations of this method and to provide qualitative understanding of various parameters involved in this method.

This article presents reaction rate data for the simple hydrolysis of acetic anhydride in the acetonitrile/water and acetone/water cosolvent systems and regression analyses using recently developed thermodynamic rate equations that contain electrostatic and solvent-solute terms. The isomole fraction plots for these reaction systems are linear, and previous theoretical work has shown that the electrostatic term is negligible for such systems. On the other hand, the reaction rates are dependent upon the cosolvent mole fraction, indicating that the solvent-solute term, which is modeled empirically, is significant. The results of the analyses provide the foundation for a paradigm shift away from the emphasis on electrostatic effects to more tenable explanations of kinetic behavior in solvent systems.

<div><p></p><p><i>Key Question: How to develop technologies to understand and solve a multi-scale global crisis resulting from rapid transmission of contagious respiratory viruses in pandemic phases?</i></p> <p>A two-pronged approach to optimize the existing solutions and combat the DIRECT and INDIRECT transmission of respiratory pathogens.</p> <p>• I. Optimization of multiple layers in a filter/ mask with physical – biochemical properties</p> <p>• II. Characterization of surfaces based on best parameters for disinfection using electrostatic deposition </p> <p> </p><br><p></p></div>

A deeper understanding of human development and disease is made possible partly through the study of genetically modified model organisms, such as the common mouse (Mus musculus). By genetically modifying such model organisms, scientists can activate, deactivate, or highlight particular characteristics. A genetically modified animal is generated by adding exogenous (foreign) genetic material to one or more embryonic cells at their earliest stages of development. Frequently, this exogenous genetic material consists of specially engineered DNA, which is introduced into a fertilized egg cell (zygote). When successfully introduced into the zygote, the exogenous DNA will be incorporated into the cell's own genome, and the animal that develops from the zygote will exhibit the genetic modification in all of its cells. The current devices and methods for generating genetically modified animals are inefficient, and/or difficult to use. The most common and efficient method for inserting new DNA into zygotes is by directly injecting a DNA solution through a tiny glass tube into the cell in a process called microinjection. Unfortunately, microinjection is quite inefficient (success rates are commonly between 1 and 5%), but often it is the only method for inserting DNA into eggs, zygotes, or early stage embryos. This thesis presents the design and testing of a micrometer sale, pumpless microelectromechanical system (MEMS) nanoinjector. Rather than use pumps and capillaries, the nanoinjector employs electrostatic charges to attract and repel DNA onto and off of the surface of a solid lance. The nanoinjector also includes a mechanical system for constraining the target cells during injection. Initial testing indicates the nanoinjector does not decrease cell viability, and it has a very high initial success rate (up to 90%). With the addition of an on-chip actuator, the nanoinjector could be packaged as an inexpensive, fully automated system, enabling efficient, high volume genetic modification of developing animals. Such a device would greatly increase the ease and speed of generating the model organisms needed to study such critical diseases such as Alzheimer's disease, cancer, and diabetes.

The electrostatic ion beam trap (EIBT) was designed by D. Zajfman during the previous decade. This ion trap combines many properties of the Fourier-transform ion cyclotron resonance (FTICR) mass analyzer and time-of-flight (TOF) mass analyzer. There are several advantages for the electrostatic ion beam trap. First, large mass-to-charge particles in an electrostatic field could be easier to analyze. Second, there is a folded flight path, which could make the mass analyzer smaller compared to conventional TOF mass analyzer. This principle of operation of this ion trap is analogous to an optical resonator. The ions are trapped in a voltage valley and oscillate between the two parallel sets of mirror electrodes with high voltages. In this thesis, I first describe a new type of miniaturized electrostatic ion beam trap mass analyzer that consists of two printed circuit boards (PCBs). The facing surfaces of these boards are imprinted with copper electrodes. The center of the boards is field free and at ground potential with ion mirrors and Einzel lenses on either side. A charge detector is attached to the center for recording the time-dependant motion of the ions in the field. The PCB-based EIBT design is easier to construct than the original EIBT mass analyzer. The electrostatic fields are optimized by adjusting the potential on the mirror electrodes as well as the geometry of the electrodes. Although nondestructive charge detection is much less sensitive for small ions, this detection is ideal for analysis of large ions. The planar electrostatic ion beam trap is inexpensive, small, and simple to operate. The PCB EIBT device was designed, built, and tested using metal samples such as copper and nickel. The electric field of the PCB EIBT is not the same as that of the original EIBT. Unfortunately, there were no ion signals captured in image charge detector. Another new type of miniaturized electrostatic ion beam trap was made by depositing electrodes onto Kapton film. Seven thin tin/copper traces (1 mm wide by 0.015 mm thick) were deposited onto each side of a flat, flexible circuit board substrate (Kapton film 0.15 mm thickness). The film was rolled to form a cylinder. The flexible EIBT is small (4.5 cm × 8 cm), and lightweight (~1 g). This device was tested using laser ablation of CsI. The CsI signals were detected by the charge detector, amplified and sent to the oscilloscope. Fourier transformation was used to convert the data to the frequency domain spectrum. The resolution of Cs+ is around 1000 (m/Δm) from initial flexible EIBT test. The mass accuracy of the Cs+ peak is better than 0.1%.

Electrostatic Discharges (ESD) is a significant hazard to electronic components and systems. Based on a specific process technology, a given circuit application requires a customized ESD consideration that meets all the requirements such as the core circuit's operating condition, maximum accepted leakage current, breakdown conditions for the process and overall device sizes. In every several years, there will be a new process technology becomes mature, and most of those new technology requires custom design of effective ESD protection solution. And usually the design window will shrinks due to the evolving of the technology becomes smaller and smaller. The ESD related failure is a major IC reliability concern and results in a loss of millions dollars each year in the semiconductor industry. To emulate the real word stress condition, several ESD stress models and test methods have been developed. The basic ESD models are Human Body model (HBM), Machine Mode (MM), and Charge Device Model (CDM). For the system-level ESD robustness, it is defined by different standards and specifications than component-level ESD requirements. International Electrotechnical Commission (IEC) 61000-4-2 has been used for the product and the Human Metal Model (HMM) has been used for the system at the wafer level. Increasingly stringent design specifications are forcing original equipment manufacturers (OEMs) to minimize the number of off-chip components. This is the case in emerging multifunction mobile, industrial, automotive and healthcare applications. It requires a high level of ESD robustness and the integrated circuit (IC) level, while finding ways to streamline the ESD characterization during early development cycle. To enable predicting the ESD performance of IC's pins that are directly exposed to a system-level stress condition, a new the human metal model (HMM) test model has been introduced. In this work, a new testing methodology for product-level HMM characterization is introduced. This testing framework allows for consistently identifying ESD-induced failures in a product, substantially simplifying the testing process, and significantly reducing the product evaluation time during development cycle. It helps eliminates the potential inaccuracy provided by the conventional characterization methodology. For verification purposes, this method has been applied to detect the failures of two different products. Addition to the exploration of new characterization methodology that provides better accuracy, we also have looked into the protection devices itself. ICs for emerging high performance precision data acquisition and transceivers in industrial, automotive and wireless infrastructure applications require effective and ESD protection solutions. These circuits, with relatively high operating voltages at the Input/Output (I/O) pins, are increasingly being designed in low voltage Complementary Metal-Oxide-Semiconductor (CMOS) technologies to meet the requirements of low cost and large scale integration. A new dual-polarity SCR optimized for high bidirectional blocking voltages, high trigger current and low capacitance is realized in a sub 3-V, 180-nm CMOS process. This ESD device is designed for a specific application where the operating voltage at the I/O is larger than that of the core circuit. For instance, protecting high voltage swing I/Os in CMOS data acquisition system (DAS) applications. In this reference application, an array of thin film resistors voltage divider is directly connected to the interface pin, reducing the maximum voltage that is obtained at the core device input down to ± 1-5 V. Its ESD characteristics, including the trigger voltage and failure current, are compared against those of a typical CMOS-based SCR. Then, we have looked into the ESD protection designs into more advanced technology, the 28-nm CMOS. An ESD protection design builds on the multiple discharge-paths ESD cell concept and focuses the attention on the detailed design, optimization and realization of the in-situ ESD protection cell for IO pins with variable operation voltages. By introducing different device configurations fabricated in a 28-nm CMOS process, a greater flexibility in the design options and design trade-offs can be obtained in the proposed topology, thus achieving a higher integration and smaller cell size definition for multi-voltage compatibility interface ESD protection applications. This device is optimized for low capacitance and synthesized with the circuit IO components for in-situ ESD protection in communication interface applications developed in a 28-nm, high-k, and metal-gate CMOS technology. ESD devices have been used in different types of applications and also at different environment conditions, such as high temperature. At the last section of this research work, we have performed an investigation of several different ESD devices' performance under various temperature conditions. And it has been shown that the variations of the device structure can results different ESD performance, and some devices can be used at the high temperature and some cannot. And this investigation also brings up a potential threat to the current ESD protection devices that they might be very vulnerable to the latch-up issue at the higher temperature range.

<p>Electrostatic spray is a spray that is induced by an interaction between the surface charge on the liquid meniscus and the externally applied electrical field that forms a conical shape known as the Taylor Cone. Electrostatic spray can be seen in a variety of different fields in modern times, such as, agriculture, combustion, space propulsion, and medical applications. The experimental setup for any electrostatic spray consists of the following components: a syringe pump filled with an ionic fluid, a high voltage power supply, and a ground source. The orientation of the nozzle, set to a horizontal or vertical orientation, and the interface that is examined, liquid/air or liquid/liquid interface are two parameters that can vary from one setup to another while still using the same components to form the electrostatic spray. In this experimental study, the characteristic of the electrostatic spray of two immiscible fluids, liquid/liquid interface, with a horizontal nozzle orientation, was analyzed. The two immiscible fluids that were chosen for this experiment were olive oil, the ambient fluid, and pure ethanol, the working fluid. A set range of 0 – 5 kV with an increment of 0.5 kV was applied to the working fluid with a flowrate of 0.1 mL/min. The distance between the nozzle and the copper disk was also altered for three different distances, 22.09, 14.6 and 10.33 mm. Different patterns and trajectories were captured and analyzed using both a high-speed camera and a long exposure camera. Formation of vortices was recorded in the induced flow. The general trend was found was an increase in the droplets’ velocity with the increase of the applied voltage. Additionally, there was an increase in the droplets’ velocity was recorded as the copper disk was moved closer to the nozzle. A dimensional number, Jowaiser’s number Jo, has been proposed where it relates the electric forces to the inertial forces. It can be used to predicts the phase that the flow experiences. The four phases that a flow can experience are the droplet phase, transition phase, spray phase, and the shorting phase.  </p>