The second edition of Extrusion is designed to aid operators, engineers, and managers in extrusion processing in quickly answering practical day-to-day questions. The first part of the book provides the fundamental principles, for operators and engineers, of polymeric materials extrusion processing in single and twin screw extruders. The next section covers advanced topics including troubleshooting, auxiliary equipment, and coextrusion for operators, engineers, and managers. The final part provides applications case studies in key areas for engineers such as compounding, blown film, extrusion blow molding, coating, foam, and reprocessing. This practical guide to extrusion brings together both equipment and materials processing aspects. It covers basic and advanced topics, for reference and training, in thermoplastics processing in the extruder. Detailed reference data are provided on such important operating conditions as temperatures, start-up procedures, shear rates, pressure drops, and safety. - A practical guide to the selection, design and optimization of extrusion processes and equipment - Designed to improve production efficiency and product quality - Focuses on practical fault analysis and troubleshooting techniques

Does assigning fifty math problems accomplish any more than assigning five? Is memorizing word lists the best way to increase vocabulary—especially when it takes away from reading time? And what is the real purpose behind those devilish dioramas? The time our children spend doing homework has skyrocketed in recent years. Parents spend countless hours cajoling their kids to complete such assignments—often without considering whether or not they serve any worthwhile purpose. Even many teachers are in the dark: Only one of the hundreds the authors interviewed and surveyed had ever taken a course specifically on homework during training. The truth, according to Sara Bennett and Nancy Kalish, is that there is almost no evidence that homework helps elementary school students achieve academic success and little evidence that it helps older students. Yet the nightly burden is taking a serious toll on America’s families. It robs children of the sleep, play, and exercise time they need for proper physical, emotional, and neurological development. And it is a hidden cause of the childhood obesity epidemic, creating a nation of “homework potatoes.” In The Case Against Homework, Bennett and Kalish draw on academic research, interviews with educators, parents, and kids, and their own experience as parents and successful homework reformers to offer detailed advice to frustrated parents. You’ll find out which assignments advance learning and which are time-wasters, how to set priorities when your child comes home with an overstuffed backpack, how to talk and write to teachers and school administrators in persuasive, nonconfrontational ways, and how to rally other parents to help restore balance in your children’s lives. Empowering, practical, and rigorously researched, The Case Against Homework shows how too much work is having a negative effect on our children’s achievement and development and gives us the tools and tactics we need to advocate for change. Also available as an eBook

Does your child dream of winning a school spelling bee, or even competing in the Scripps National Spelling Bee in the Washington, D.C., area? You've found the perfect place to start. Words of the Champions: Your Key to the Bee is the new official study resource from the Scripps National Spelling Bee. Help prepare your child for a 2020 or 2021 classroom, grade-level, school, regional, district or state spelling bee with this list of 4,000 spelling words. The School Spelling Bee Study List, featuring 450 words, is part of the total collection. All words in this guide may be found in our official dictionary, Merriam-Webster Unabridged (http: //unabridged.merriam-webster.com/)

This authoritative catalogue of the Corcoran Gallery of Art's renowned collection of pre-1945 American paintings will greatly enhance scholarly and public understanding of one of the finest and most important collections of historic American art in the world. Composed of more than 600 objects dating from 1740 to 1945.

Blueprints is a concise yet comprehensive coverage of Object-Oriented Analysis and Design concepts, suitable for a second programming course in Computer Science. It introduces and teaches application development in a command-line environment, and assumes basic expertise with the Java programming language.

Have you ever wondered how the ideas behind the world’s greatest architectural designs came about? What process does an architect go through to design buildings which become world-renowned for their excellence? This book reveals the secrets behind these buildings. He asks you to ‘read’ the building and understand its starting point by analyzing its final form. Through the gradual revelations made by an understanding of the thinking behind the form, you learn a unique methodology which can be used every time you look at any building.