Analytical Parametric Model Used to Study the Influence of Electrostatic Force on Surface Coverage During Electrospinning of Polymer Fibers

Electrospinning (ES) can readily produce polymer fibers with cross-sectional dimensions ranging from tens of nanometers to tens of microns. Qualitative estimates of surface area coverage are rather intuitive. However, quantitative analytical and numerical methods for predicting surface coverage during ES have not been covered in sufficient depth to be applied in the design of novel materials, surfaces, and devices from ES fibers. This article presents a modeling approach to ES surface coverage where an analytical model is derived for use in quantitative prediction of surface coverage of ES fibers. The analytical model is used to predict the diameter of circular deposition areas of constant field strength and constant electrostatic force. Experimental results of polyvinyl alcohol fibers are reported and compared to numerical models to supplement the analytical model derived. The analytical model provides scientists and engineers a method for estimating surface area coverage. Both applied voltage and capillary-to-collection-plate separation are treated as independent variables for the analysis. The electric field produced by the ES process was modeled using COMSOL Multiphysics software to determine a correlation between the applied field strength and the size of the deposition area of the ES fibers. MATLAB scripts were utilized to combine the numerical COMSOL results with derived analytical equations. Experimental results reinforce the parametric trends produced via modeling and lend credibility to the use of modeling techniques for the qualitative prediction of surface area coverage from ES. (Copyright: 2014 American Vacuum Society.)

The Electrolytic Deposition of Chromium Upon Aluminum

The purpose or this investigation is primarily to determine the best conditions for plating chromium on aluminum. The work was carried out with the hope of obtaining coherent deposits, and of determin­ing the conditions under which such deposits may be duplicated.

The Effect of Hydrogen Overvoltage on the Electrolytic Deposition of Zinc

In the deposition of metallic zinc by electro­lysis from neutral or acid solution, little difficulty is experienced provided certain impurities are absent from the electrolyte. The use of the process has long been considered as a potential source, patents on the process having been issued as early as 1880. However, the early experimenters failed to realize the importance of impurities in the electrolyte, and for this reason, the process suffered several severe setbacks when commercial plants were built.

Effect of Manganese and Arsenic upon Current Efficiency in the Deposition of Zinc from Zinc Sulphate Solution

Throughout the entire experiment the electrolysis were conducted in an eight-hundred cubic centimeter beaker. An excellent circulation of the solution was assured by means of an electric stirrer, vigorous gas evolution from the anodes, and by means of a regulated feed-discharge system. By means of this balance, solution of the same impurity concentration as that of the electrolyte was fed in the cell just as fast as the discharge was syphoned out.

The Deposition of Monomolecular Films.

The formation of monomolecular films is possible because of the action of the heteropolar molecules of certain fatty acids, especially stearic. Under the proper conditions the acid will spread out until a monomolecular film is formed.

The Theory of Alloy Deposition and The Effect of a Rotating Cathode Upon Such Deposition, with Special Attention to the Possibility of Depositing Sterling Silver

In the past few years a great deal of atten­tion has been given to the electrodeposition of alloys. For the main part, this investigation has been of scien­tific interest only; but in a few instances, such work has attained commercial importance.

Electrolytic Deposition of Iron

In this thesis the purpose was to obtain a good iron deposit from a relatively simple bath. The deposit was to be of good nature and low in Carbon content. Also included is a summary of the uses to which electrolytic iron can be put as well as a summary of work done by other researchers in depositing iron electrolytically.

Electro-Deposition of Iron from a Chloride Bath

Iron was electro-deposited from a ferrous chloride bath. Studies were made of deposits formed when current density was varied, and fin­ally when both current density and temperature were changed. An attempt was made to lay the ground work for a long range study of the chloride bath, and to determine the most simple conditions possible for obtaining a smooth, even, and thick deposit.