Alaska News Nightly February 2 2015

first_imgStories are posted on the APRN news page. You can subscribe to APRN’s newsfeeds via email, podcast and RSS. Follow us on Facebook at alaskapublic.org and on Twitter @aprn.Download AudioLegislature Plans For Gasline Special SessionAlexandra Gutierrez, APRN – JuneauRepublican leaders expect that the Legislature will go ahead with a special session in October to consider a natural gas policy.Sex Workers Want Lobbyist in JuneauAlexandra Gutierrez, APRN-JuneauEvery legislative session, different interest groups will hire lobbyists to influence legislation that affects them. But what happens if you’re already on the wrong side of the law? A sex worker group is trying to raise money to send one of their own to Juneau.Arctic Standards Won’t Be Ready For Shell’s ReturnLiz Ruskin, APRN-Washington, DCAfter Shell’s troubled 2012 drilling season in the far north, the Interior Department began working on Arctic-specific standards for offshore drilling. But those new standards aren’t done yet.String Of Earthquakes Shakes Up Pribilof IslandsLauren Rosenthal, KUCB-UnalaskaThe Pribilof Islands aren’t usually prone to shaking. But more than a dozen earthquakes have been recorded in between St. Paul and St. George in the last few days.Child Center Leaving UAA, Frustrating ParentsJosh Edge, KSKA-AnchorageTanaina Child Development Center at the University of Alaska last week received notice from the University that the center will need to find a new location. The decision has left many parents frustrated, but the two sides are still in discussions to see if a new agreement can be reached.Alaska Regional Hospital To Open Mountain View ClinicAnnie Feidt, APRN-AnchorageAlaska Regional Hospital is planning to open a healthcare clinic in Mountain View by the end of year. There aren’t any primary care services in the neighborhood currently.Alaska Legislature Takes Second Look at Erin’s LawDaysha Eaton, KYUK-BethelErin’s Law is back in the legislature. If passed, the bill would require school districts, statewide, to provide age-appropriate K-12 sexual abuse education.Poor Design Led to BC Mine Tailings Pond FailureEd Schoenfeld, CoastAlaska-JuneauPoor design led to last summer’s catastrophic failure of a British Columbia mine tailings pond. That’s the conclusion of an investigation ordered by provincial officials and released last Friday.Vets Check Yukon Quests DogsEmily Schwing, KUAC-FairbanksOver the weekend, veterinarians looked over the sled dogs that will run the Yukon Quest International Sled Dog Race in both Fairbanks and Whitehorse. The vets wanted to make sure the dogs were healthy, well-fed and ready to race on the 1,000-mile trail.last_img read more

Material inspired by ocean mussels could lead to selfhealing plastics

first_img Mechanical tests show that adding new links in a polymer makes the material up to 1000 times stiffer. Country * Afghanistan Aland Islands Albania Algeria Andorra Angola Anguilla Antarctica Antigua and Barbuda Argentina Armenia Aruba Australia Austria Azerbaijan Bahamas Bahrain Bangladesh Barbados Belarus Belgium Belize Benin Bermuda Bhutan Bolivia, Plurinational State of Bonaire, Sint Eustatius and Saba Bosnia and Herzegovina Botswana Bouvet Island Brazil British Indian Ocean Territory Brunei Darussalam Bulgaria Burkina Faso Burundi Cambodia Cameroon Canada Cape Verde Cayman Islands Central African Republic Chad Chile China Christmas Island Cocos (Keeling) Islands Colombia Comoros Congo Congo, the Democratic Republic of the Cook Islands Costa Rica Cote d’Ivoire Croatia Cuba Curaçao Cyprus Czech Republic Denmark Djibouti Dominica Dominican Republic Ecuador Egypt El Salvador Equatorial Guinea Eritrea Estonia Ethiopia Falkland Islands (Malvinas) Faroe Islands Fiji Finland France French Guiana French Polynesia French Southern Territories Gabon Gambia Georgia Germany Ghana Gibraltar Greece Greenland Grenada Guadeloupe Guatemala Guernsey Guinea Guinea-Bissau Guyana Haiti Heard Island and McDonald Islands Holy See (Vatican City State) Honduras Hungary Iceland India Indonesia Iran, Islamic Republic of Iraq Ireland Isle of Man Israel Italy Jamaica Japan Jersey Jordan Kazakhstan Kenya Kiribati Korea, Democratic People’s Republic of Korea, Republic of Kuwait Kyrgyzstan Lao People’s Democratic Republic Latvia Lebanon Lesotho Liberia Libyan Arab Jamahiriya Liechtenstein Lithuania Luxembourg Macao Macedonia, the former Yugoslav Republic of Madagascar Malawi Malaysia Maldives Mali Malta Martinique Mauritania Mauritius Mayotte Mexico Moldova, Republic of Monaco Mongolia Montenegro Montserrat Morocco Mozambique Myanmar Namibia Nauru Nepal Netherlands New Caledonia New Zealand Nicaragua Niger Nigeria Niue Norfolk Island Norway Oman Pakistan Palestine Panama Papua New Guinea Paraguay Peru Philippines Pitcairn Poland Portugal Qatar Reunion Romania Russian Federation Rwanda Saint Barthélemy Saint Helena, Ascension and Tristan da Cunha Saint Kitts and Nevis Saint Lucia Saint Martin (French part) Saint Pierre and Miquelon Saint Vincent and the Grenadines Samoa San Marino Sao Tome and Principe Saudi Arabia Senegal Serbia Seychelles Sierra Leone Singapore Sint Maarten (Dutch part) Slovakia Slovenia Solomon Islands Somalia South Africa South Georgia and the South Sandwich Islands South Sudan Spain Sri Lanka Sudan Suriname Svalbard and Jan Mayen Swaziland Sweden Switzerland Syrian Arab Republic Taiwan Tajikistan Tanzania, United Republic of Thailand Timor-Leste Togo Tokelau Tonga Trinidad and Tobago Tunisia Turkey Turkmenistan Turks and Caicos Islands Tuvalu Uganda Ukraine United Arab Emirates United Kingdom United States Uruguay Uzbekistan Vanuatu Venezuela, Bolivarian Republic of Vietnam Virgin Islands, British Wallis and Futuna Western Sahara Yemen Zambia Zimbabwe Mussels have the best of both worlds: They create natural polymer networks with both covalent and charged “ionic” bonds. In recent years, researchers have begun to mimic this approach. They’ve added negatively charged chemical groups called catechols to soft, gellike polymers that already have covalent connections. When they then add positively charged iron atoms to a solution of their polymers, each iron atom grabs multiple nearby catechols on separate polymer strands, creating extra links that help toughen up the soft gels.The problem is that when these polymers are made in water, as has been the case thus far, the liquid causes the gels to expand like a sponge, says Megan Valentine, a materials scientist at the University of California, Santa Barbara. That makes them nearly fully expanded from the get-go; if you pull on them, they can’t stretch much farther and simply break.So, Valentine and her colleagues set out to see whether they could adapt the strategy to work with a dry polymer. They started with a gel polymer that harbors a loose network of covalent bonds called polyethylene glycol (PEG). When they synthesized their PEG, they added catechol groups to individual polymer strands. Left to their own devices, catechols readily react with oxygen in either air or water. To prevent this, Valentine and her colleagues temporarily covered the catechols with capping groups. Then, just before strengthening the polymer, they added acid, which tore off the caps. Valentine’s team then spritzed in a small amount of iron atoms, which diffused through the PEG, with each iron atom reacting with multiple catechols, adding a second network of links.Finally, the researchers dried out their polymer and tested it. They found that the dried polymer was between 100 and 1000 times stiffer than the original PEG yet flexible enough to absorb large amounts of energy before breaking, they report today in Science. This transformed their previous gellike material into one that was strong and flexible like leather. Although this specific polymer isn’t either the strongest or most flexible plastic on the market, adding the secondary network produced a change that’s rarely produced when making a single change to a polymer.“It’s remarkable to have such an improvement in stiffness,” says Costantino Creton, a materials scientist at the École Supérieure de Physique et de Chimie Industrielles in Paris who was not involved with the work. The question now, he says, is whether the same strategy might work to strengthen other polymers.It should, says Karen Winey, a materials scientist at the University of Pennsylvania. “There’s no reason why you have to use PEG. It’s quite generalizable.” And because of that, Winey says, “I think it’s really a nice piece of work.”Valentine adds that she and her colleagues are already exploring this strategy for other polymers. However, she notes, because the new material has already shown that it can withstand forces that would rupture normal PEG-based materials, it might already prove useful in creating tough biomaterials, such as artificial tendons or joints for robots to help prevent wear and tear. Email University of California, Santa Barbara Mechanical tests show that adding new links in a polymer makes the material up to 1000 times stiffer. Erin Vitali/500 px Adding iron creates a polymer that is stiff, yet still flexible. University of California, Santa Barbara Material inspired by ocean mussels could lead to self-healing plastics University of California, Santa Barbara Materials scientist Emmanouela Filippidi of the University of California, Santa Barbara, examines an iron-treated polymer. ‹› New polymers mimic the way ocean mussels hold fast to rocks. By Robert F. ServiceOct. 26, 2017 , 2:00 PM University of California, Santa Barbara Sign up for our daily newsletter Get more great content like this delivered right to you! Country Erin Vitali/500 px Saltwater mussels are some of the world’s clingiest creatures, able to stay stuck to slippery rocks while being thrashed by pounding surf. Now, researchers have designed a polymer that would make these bivalves proud. The stretchy—yet strong—material could lead to a new family of plastics that are tough enough to glue together disparate materials such as wood and metal, and even able to heal themselves when damaged.Materials scientists have long relied on several strategies for making polymers, which consist of long, chainlike molecules and which can stretch and return to their original shape, like rubber bands. The most common approach forges chemical links, called covalent bonds, between separate polymer chains, turning what looks like a bunch of separate spaghetti strands into a loose, 3D mesh. Such polymers can be stiff, and thereby able to resist being pulled apart. But they typically aren’t strong: If you pull on them too hard they break, like a rubber band yanked too far.A second strategy places positive and negative electrical charges on separate polymer strands, which then bond together, creating a loose network. These materials can be more flexible than covalently bound polymers, and because the links between opposite charges can reattach after being pulled apart, they can essentially “heal” themselves to regain their original shape. Click to view the privacy policy. Required fields are indicated by an asterisk (*) New polymers mimic the way ocean mussels hold fast to rocks.last_img read more