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Jonathan Tobin: Defending the Right to a Jewish State

Heather Hale: Compliment your kids without giving them big heads

Megan Shauri: 10 ways you are ruining your own happiness

Carolyn Bigda: 8 Best Dividend Stocks for 2015

Kiplinger's Personal Finance editors: 7 Things You Didn't Know About Paying Off Student Loans

Samantha Olson: The Crucial Mistake 55% Of Parents Are Making At Their Baby's Bedtime

Densie Well, Ph.D., R.D. Open your eyes to yellow vegetables

The Kosher Gourmet by Megan Gordon With its colorful cache of purples and oranges and reds, COLLARD GREEN SLAW is a marvelous mood booster --- not to mention just downright delish
April 18, 2014

Rabbi Yonason Goldson: Clarifying one of the greatest philosophical conundrums in theology

Caroline B. Glick: The disappearance of US will

Megan Wallgren: 10 things I've learned from my teenagers

Lizette Borreli: Green Tea Boosts Brain Power, May Help Treat Dementia

John Ericson: Trying hard to be 'positive' but never succeeding? Blame Your Brain

The Kosher Gourmet by Julie Rothman Almondy, flourless torta del re (Italian king's cake), has royal roots, is simple to make, . . . but devour it because it's simply delicious

April 14, 2014

Rabbi Dr Naftali Brawer: Passover frees us from the tyranny of time

Greg Crosby: Passing Over Religion

Eric Schulzke: First degree: How America really recovered from a murder epidemic

Georgia Lee: When love is not enough: Teaching your kids about the realities of adult relationships

Cameron Huddleston: Freebies for Your Lawn and Garden

Gordon Pape: How you can tell if your financial adviser is setting you up for potential ruin

Dana Dovey: Up to 500,000 people die each year from hepatitis C-related liver disease. New Treatment Has Over 90% Success Rate

Justin Caba: Eating Watermelon Can Help Control High Blood Pressure

The Kosher Gourmet by Joshua E. London and Lou Marmon Don't dare pass over these Pesach picks for Manischewitz!

April 11, 2014

Rabbi Hillel Goldberg: Silence is much more than golden

Caroline B. Glick: Forgetting freedom at Passover

Susan Swann: How to value a child for who he is, not just what he does

Cameron Huddleston: 7 Financial Tasks You Should Tackle Right Now

Sandra Block and Lisa Gerstner: How to Profit From Your Passion

Susan Scutti: A Simple Blood Test Might Soon Diagnose Cancer

Chris Weller: Have A Slow Metabolism? Let Science Speed It Up For You

The Kosher Gourmet by Diane Rossen Worthington Whitefish Terrine: A French take on gefilte fish

April 9, 2014

Jonathan Tobin: Why Did Kerry Lie About Israeli Blame?

Samuel G. Freedman: A resolution 70 years later for a father's unsettling legacy of ashes from Dachau

Jessica Ivins: A resolution 70 years later for a father's unsettling legacy of ashes from Dachau

Kim Giles: Asking for help is not weakness

Kathy Kristof and Barbara Hoch Marcus: 7 Great Growth Israeli Stocks

Matthew Mientka: How Beans, Peas, And Chickpeas Cleanse Bad Cholesterol and Lowers Risk of Heart Disease

Sabrina Bachai: 5 At-Home Treatments For Headaches

The Kosher Gourmet by Daniel Neman Have yourself a matzo ball: The secrets bubby never told you and recipes she could have never imagined

April 8, 2014

Lori Nawyn: At Your Wit's End and Back: Finding Peace

Susan B. Garland and Rachel L. Sheedy: Strategies Married Couples Can Use to Boost Benefits

David Muhlbaum: Smart Tax Deductions Non-Itemizers Can Claim

Jill Weisenberger, M.S., R.D.N., C.D.E : Before You Lose Your Mental Edge

Dana Dovey: Coffee Drinkers Rejoice! Your Cup Of Joe Can Prevent Death From Liver Disease

Chris Weller: Electric 'Thinking Cap' Puts Your Brain Power Into High Gear

The Kosher Gourmet by Marlene Parrish A gift of hazelnuts keeps giving --- for a variety of nutty recipes: Entree, side, soup, dessert

April 4, 2014

Rabbi David Gutterman: The Word for Nothing Means Everything

Charles Krauthammer: Kerry's folly, Chapter 3

Amy Peterson: A life of love: How to build lasting relationships with your children

John Ericson: Older Women: Save Your Heart, Prevent Stroke Don't Drink Diet

John Ericson: Why 50 million Americans will still have spring allergies after taking meds

Cameron Huddleston: Best and Worst Buys of April 2014

Stacy Rapacon: Great Mutual Funds for Young Investors

Sarah Boesveld: Teacher keeps promise to mail thousands of former students letters written by their past selves

The Kosher Gourmet by Sharon Thompson Anyone can make a salad, you say. But can they make a great salad? (SECRETS, TESTED TECHNIQUES + 4 RECIPES, INCLUDING DRESSINGS)

April 2, 2014

Paul Greenberg: Death and joy in the spring

Dan Barry: Should South Carolina Jews be forced to maintain this chimney built by Germans serving the Nazis?

Mayra Bitsko: Save me! An alien took over my child's personality

Frank Clayton: Get happy: 20 scientifically proven happiness activities

Susan Scutti: It's Genetic! Obesity and the 'Carb Breakdown' Gene

Lecia Bushak: Why Hand Sanitizer May Actually Harm Your Health

Stacy Rapacon: Great Funds You Can Own for $500 or Less

Cameron Huddleston: 7 Ways to Save on Home Decor

The Kosher Gourmet by Steve Petusevsky Exploring ingredients as edible-stuffed containers (TWO RECIPES + TIPS & TECHINQUES)

Jewish World Review

How dry cleaning works

By Marshall Brain

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http://www.JewishWorldReview.com | (MCT) >Everyone has seen a washing machine. You throw in a load of clothes, add soap and turn it on. Gallons of water pour in to wash and rinse the clothes. It's not that different from the days of washing clothes in the river.

Dry cleaning, on the other hand, is a mystery. You drop off your clothes, and then what? How can you clean something without using water?

The reason it is called "dry" cleaning is not because it is dry. It's because the process uses something other than water as the solvent. In the early days of dry cleaning, the solvent might have been kerosene or some other petroleum-based solvent. Today the most common solvent is called perchlorethylene, or perc. There are two advantages to avoiding water. First, a solvent like perc works better than water on oily stains. Second, most natural fibers that would shrink or fade in water don't shrink or fade in a "dry" solvent.

Because a dry cleaner uses a solvent, however, the "washing machine" is much more complex. A typical dry cleaning machine is massive and can hold up to 100 pounds of clothes. It circulates and reuses the solvent, so there are pumps and filters in the machine to keep the solvent clean. A typical machine might pump 1,500 gallons of solvent per hour through its filters, spraying clean solvent on the clothes continuously.

Once the wash cycle finishes, pumps move all the solvent to a storage tank. The same machine dries the clothes. Warm air flows through the clothes and evaporates the solvent. Cold coils condense the solvent in the air back to a liquid and recycle it so that the solvent does not end up in the environment. There is a tiny amount of solvent left in the cloth, and that is what you smell when you pick up your clothes from the cleaner. The good news is that perc smells better than the kerosene used in the past.

There is more to dry cleaning than just the washing. When you drop off your clothes at the cleaner, the first step is tagging. Each garment you bring gets a numbered tag that helps keep track of your order. Then the clothes are checked for stains and damage, and anything left in the pockets gets removed. Stains are pre-treated with chemicals. The clothes go into the dry cleaning machine, come out and get inspected again. Then they go to a set of rather surprising ironing machines. There are machines specially shaped so they can quickly iron sleeves, collars, shirts and pants. Then your order is assembled, bagged and hung.

Even though 85 percent of the 30,000 dry cleaners in the United States use perc, there is a movement to phase it out because it has several environmental problems. Perc is toxic, and when spilled it gets into the air and water and can affect worker health. There is evidence that perc causes cancer in rats and people. Perc also off-gases in your home and some people are very sensitive to it. So dry cleaners have been trying to find a better, less toxic alternative.

One possibility is liquid carbon dioxide. If you pressurize pure carbon dioxide gas, it turns into a liquid that makes a very good solvent. A dry cleaning machine that uses liquid carbon dioxide is similar to a perc dry cleaning machine. The main difference is the pressurization. The liquid carbon dioxide circulates through the clothes using pumps and filters. The advantage of liquid carbon dioxide is that it is harmless to the environment. If spilled, it turns immediately to gas and dissipates into the air. There is no solvent left in your clothes to out-gas either.

There are other possibilities as well. Oil companies are trying to develop better petroleum solvents. Silicone liquid is a possibility. There is even some experimentation using water and ultrasonic waves, much like the system used to clean jewelry at a jewelry store. With all of these different dry cleaning systems, the goal is the same: to clean your clothes thoroughly, without shrinking or fading the fabric.

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Previously:


How exoskeletons work
How an oil refinery works
How landfills work
How the Orion spacecraft works
The cutting edge in HDTV
Redefining the CD
How the HDMI cable scam works
How glow-in-the-dark toys work
How the subprime mortgage crisis works
How gift cards work
How Tasers work
How giant TV screens work
How foreclosure works
How Air Force One works
How wildfire fighting works
How vitamins work
How ejection seats work
How reattaching limbs works
How hot air balloons work
How paparazzi work
How counterfeiting works
How CDs work
How the Edsel worked
How Stinger missiles work
How hybrid cars work
How sharks work
How mosquitoes work
How diesel engines work
How water towers work
How the Dawn mission works
How Kassam rockets work
How the North American Eagle works
Why aren't we flying to work?
How tofu and soy milk work
How Colony Collapse Disorder works
How airbags work
How the U.S. income tax works
How gum works
How caffeine works
How Daylight Saving Time works
How a cruise missile works
How snow making works

© 2007, How Stuff Works Inc. Distributed by McClatchy-Tribune Information Services.

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