Evaluation of a Centrifuge Consolidation Technique to Determine the Effects of Temperature and Time on Kaolinite Properties

Abstract The effects of time and temperature on the moisture content and unit weight profiles, as developed during a centrifuge consolidation process, were observed during the research program that is described herein. Specifically, a Beckman-Coulter Model J6-MI centrifuge with a six-place JS-4.2A swinging bucket rotor was utilized to consolidate kaolinite slurry samples. The consolidation procedure utilized specially designed slurry consolidometers, made from acrylic tubes with inside diameters of 2.63 inches (6.67 cm) and heights of 5.13 inches (13.04 cm). The tested kaolinite slurry samples were created by mixing 400 grams of dry kaolinite clay powder with 200 grams of de-aired deionized water (DI water) to reach an initial water content of 50 percent. Temperatures of - 10, 0 and 20℃ were utilized within the centrifuge with spin times of 12, 18, 24, and 30 hours. After being removed from the centrifuge, each soil specimen was trimmed into multiple slices of approximately 0.25-inch (0.64 cm) thick. The unit weight and moisture content of each individual slice were calculated and reported. The slurry samples were spun at a fixed centrifugal force of 500 revolutions per minute (RPM) that corresponded to an effective stress at the bottom of the samples of 35.57 kPa at the temperature of -10℃, 50.30 kPa at the temperature of 0℃, and 52.47 kPa at the temperature 20℃. The average unit weight values of the spun samples at 30 hours was 15.52 kN/m3 at the temperature of -10℃, 17.91 kN/m3 at the temperature of 0℃, and 18.25 kN/m3 at the temperature of 20℃. Additionally, the average moisture content values of the spun samples at 30 hours samples were 41.90 percent, 31.22 percent, and 30.22 percent for the testing temperatures of - 10, 0 and 20, respectively

Satellites of Infinite Rank in the Smooth Concordance Group

We conjecture that satellite operations are either constant or have infinite rank in the concordance group. We reduce this to the difficult case of winding number zero satellites, and use $SO(3)$ gauge theory to provide a general criterion sufficient for the image of a satellite operation to generate an infinite rank subgroup of the smooth concordance group $\mathcal{C}$. Our criterion applies widely, notably to scores of unknotted patterns for which the corresponding operators on the topological concordance group are zero. We raise some questions and conjectures regarding satellite operators and their interaction with concordance

Systemic intervention for computer-supported collaborative learning

This paper presents a systemic intervention approach as a means to overcome the methodological challenges involved in research into computer-supported collaborative learning applied to the promotion of mathematical problem-solving (CSCL-MPS) skills in schools. These challenges include how to develop an integrated analysis of several aspects of the learning process; and how to reflect on learning purposes, the context of application and participants' identities. The focus of systemic intervention is on processes for thinking through whose views and what issues and values should be considered pertinent in an analysis. Systemic intervention also advocates mixing methods from different traditions to address the purposes of multiple stakeholders. Consequently, a design for CSCL-MPS research is presented that includes several methods. This methodological design is used to analyse and reflect upon both a CSCL-MPS project with Colombian schools, and the identities of the participants in that project

Wing Optimization Technique Based on Vortex Lattice Theory

An integrated aerodynamic optimization technique based on vortex lattice theory is being proposed. The technique in this work will aim at optimizing the geometric parameters of a general wing with NACA 65-210 airfoil sections under a low speed aerodynamic regime. This will be completed by performing an aerodynamic analysis based on vortex lattice theory with the objective of satisfying a performance index function. This function will seek to optimize the high lift-to-drag ratio of the wing at cruise velocity, while maximizing theoretical cruise range and minimizing wing weight. The optimization method has been developed using MATLAB and the focus of the study will be used by Cirrus Design Corporation and implemented under the panel method software SURFACES as an optimization tool

How Literary Study Advances Belonging: The Prevalence of Colorism Through Alice Walker’s “Everyday Use”

Alexis Pinzon discusses colorism in Alice Walker\u27s short story Everyday Use ; she shows how Walker\u27s representation of colorism can help us identify and respond to discrimination in other venues, including the workplace and in mass media. The capstone paper demonstrates the central role that literature plays in fostering an understanding of race and gender discrimination and in generating new narratives that advance a more equal society