Velocity measurements of a dilute particulate suspension over and through a porous medium model

We experimentally examine pressure-driven flows of 1%, 3%, and 5% dilute suspensions over and through a porous media model. The flow of non-colloidal, non-Brownian suspensions of rigid and spherical particles suspended in a Newtonian fluid is considered at very low Reynolds numbers. The model of porous media consists of square arrays of rods oriented across the flow in a rectangular channel. Systematic experiments using high-spatial-resolution planar particle image velocimetry (PIV) and index-matching techniques are conducted to accurately measure the velocity measurements of both very dilute and solvent flows inside and on top of the porous media model. We found that for 1%, 3%, and 5% dilute suspensions the fully-developed velocity profile inside the free-flow region are well predicted by the exact solution derived from coupling the Navier-Stokes equation within the free flow-region and the volume-averaged Navier Stokes (VANS) equation for the porous media. We further analyze the velocity and shear rate at the suspension-porous interface and compare these data with those of pure suspending fluid and the related analytical solutions. The exact solution is used to define parameters necessary to calculate key values to analyze the porous media/fluid interaction such as Darcy velocity, penetration depth, and fractional ratios of the mass flow rate. These parameters are comparable between the solvent, dilute suspensions, and exact solution. However, we found clear effects between the solvent and the suspensions which shows different physical phenomenon occurring when particles are introduced into a flow moving over and through a porous media.Comment: 38 pages, 10 figure

Book Review: Metaphor and Reason in Judicial Opinions. by Haig Bosmajian.

Book review: Metaphor and Reason in Judicial Opinions. By Haig Bosmajian. Carbondale, IL: Southern Illinois University Press. 1992. Pp. xiv, 240. Reviewed by: Eileen A. Scallen

Creating Genderless God-language Through Lutheran Liturgy

Drawing on the work of feminist and queer theologies, this paper examines and challenges traditional God-language, proposing the implementation of genderless language in Christian worship liturgies. The Evangelical Lutheran Church in America (ELCA) is used as a model for potential methods of shifting God-language. This work focuses on God-language in Lutheran liturgy, focusing on Scripture, hymns, doctrine, and prayer. This work seeks to prove that implementing genderless God-language throughout the liturgy will provide ELCA leaders the opportunity to be more inclusive, while representing God’s transcendence beyond human conceptions such as gender

Eight-Legged Encounters: Using Organismal Biology to Bring Science Education to Families & Communities

Path of the Predators: A Journey Through the Living Arachnids. Illustrations by Pawl Tisdale WHAT IS AN ARTHROPOD? CREATE A CHELICERATE ASSEMBLE AN ARACHNID TISSUE PAPER FLOWER MICROSCOPE MADNESS Eight-Legged Encounters Impact Change in interest in learning about scientific discoveries among adult respondents (n = 63). Youth’s interest in science activities (n = 42). Respondents were 50% female, 50% male and ranged in age from 4 – 14 with a mean of 7.7

Eight Legged Encounters

This program was funded in part by a National Science Foundation grant (DRL–1241482 to EAH). Material was developed in collaboration with Marie- Claire Chelini, Jessie Rose Storz, Cody Storz, and Malcolm Rosenthal. Steven Schwartz, Jason Stafstrom, Kathy French, Priscilla Grew, and Judy Diamond were all extremely helpful in grant writing, facilitating the first live event, and/or discussions. Pawl Tisdale (artist) was phenomenal to work with on all aspects of the project! TABLE OF CONTENTS CLASSIFICATION & TAXONOMY STATIONS I. WHAT IS AN ARTHROPOD? page 4 a. The goal of this station is to introduce the audience to some basic information about “arthropods”. Who are they? How and why are they grouped together? Answers to these questions are achieved through a sorting game with plastic animals. II. CREATE A CHELICERATE page 14 a. This station introduces the audience to the basic characteristics of chelicerates (a group which they have learned about from Station I) by allowing them to build their own chelicerate out of clay. III. ASSEMBLE AN ARACHNID page 16 a. Arachnids are surprisingly diverse, with 11 different living orders! This station introduces the audience to the diversity of body types found within the 11 living arachnid orders through a coloring activity. SPIDER-SPECIFIC STATIONS (ORDER ARANEAE) IV. BUILD A BURROW page 20 a. The first spiders didn’t build orb webs to catch prey out of the air, but instead, built silk-lined burrows with trapdoors. This station explores the early function of spider silk. V. CRIBELLATE VS. ECRIBELLATE SILK page 22 a. Spiders have evolved two different ways to improve the efficiency of prey capture with their webs. This station explores those two evolutionary solutions. VI. WEAVE A WEB page 24 a. Orb webs (the classical web most non-biologists envision when asked to think of a spider web) are quite complex structures. How do spiders build orb webs? Do they use the same type of silk for the entire web? Answers to these questions can be obtained as participants are guided through their own web-weaving exercise. VII. CATCH A MOTH page 27 a. This station highlights the unique foraging strategy of the ‘bolas spider’ through a game in which participants try to catch a moth out of the air using a lasso. VIII. TISSUE PAPER FLOWER page 29 a. This station lets the audience create their own tissue paper flower upon which their chosen crab spider (made of paper) can forage. It introduces the fact that some spiders can change color and highlights the adaptive value of camouflage. RESEARCH-RELATED STATIONS IX. MICROSCOPE MADNESS page 33 a. This station provides the audience an opportunity to take an up-close look at spiders - to examine body parts they cannot normally see and to get them thinking about how these details might relate to an animals’ lifestyle or evolutionary history. X. COMMUNITY EXPERIMENT page 38 a. This station engages participants in a hand’s on spider feeding experiment that examines the influence of seismic (vibratory) cues on foraging success. Participants are encouraged to imagine how their results may relate to the evolution of courtship displays that incorporate specific sensory modalities. MISCELANEOUS STATIONSXI. SILKEN SPINNERS page 44 a. This station provides some “down time” for participants, where they can sit and watch the amazing footage and associated information put together by the BBC in David Attenborough’s “Silken Spinners” episode from Life in the Undergrowth.XII. SOUND STATION page 45 a. Most people do not realize that some spiders can “sing” in the form of stereotyped vibrations that are sent through a substrate, or surface upon which they are standing (e.g. a leaf, a twig, a blade of grass, etc.). Here, participants can listen to the sounds of spiders and are asked to imagine if they might find these songs attractive. XIII. SPIDER DANCE DISCO page 46 a. Not only can spiders sing, but they can also dance! Participants can observe some of the amazing dances that spiders do and can learn some of their own spider dance moves by watching the “Spider Dance Disco” XIV. READ ALOUD page 47 a. This station enables participants to play with some arachnid stuffed animals, puzzles, and to look through arachnid-related children’s books. Several books are listed as suggestions for read alouds. PATH OF PREDATORS XV. LIVING ARACHNID ORDERS page 48 a. Araneae, Amblypygi, Thelyphonida, Schizomida, Scorpiones, Solifugae, Palpigradi, Ricinulei, Pseudoscorpiones, Acari, Opilione