Navigation Links
An exquisite container
Date:11/1/2009

sacrificial templates," on which the gold cages take shape. When the silver nanocubes are heated in cloroauric acid (HAuCl4), the gold ions in the acid steal electrons from the silver atoms in the cubes. The silver dissolves and the gold precipitates.

A gold skin forms on the silver cubes as the cubes are hollowed out from within. The silver atoms enter solution through pores that form in the clipped corners of the cubes.

"But the really cool part," says Xia, "and the cool part of nanotechnology generally, is that the tiny gold cages have very different properties than bulk gold." In particular, they respond differently to light.

The physicist Michael Faraday was the first to realize that a suspension of gold particles glowed ruby-red because the particles were extremely small. "His original sample of a gold colloid is still in the Faraday Museum in London," says Xia, Ph.D., the James M. McKelvey Professor in the Department of Biomedical Engineering. "Isn't that amazing? It's over 150 years later and it's still there."

The color is caused by a physical effect called surface plasmon resonance. Some of the electrons in the gold particles are not anchored to individual atoms but instead form a free-floating electron gas. Light falling on these electrons can drive them to oscillate as one. This collective oscillation, the surface plasmon, picks a particular wavelength, or color, out of the incident light, and this is the color we see.

The strong response at a particular wavelength, called resonance, is what makes a violin string vibrate at a particular pitch or lets a kid pump a swing high in the sky by kicking at just the right moment.

What's more, the surface plasmon resonance is tunable in much the same sense that a violin is tunable.

"Faraday used solid particles to make his colloid," comments Xia. "You can tune the resonant wavelength by changing the particles' size, but only within nar
'/>"/>

Contact: Diana Lutz
dlutz@wustl.edu
314-935-5272
Washington University in St. Louis
Source:Eurekalert  

Page: 1 2 3 4 5

Related biology technology :

1. Bedford Laboratories(TM) to Begin Shipping Fluconazole Injection in PVC Flexible Containers
2. Thermo Fisher Scientific to Expand Manufacturing Operation for Single-Use Bioprocessing Containers
3. International Isotopes Inc. Announces Completion of an Exclusive Distributor Agreement for Sales of New Style Transportation Containers
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
An exquisite container
(Date:12/19/2014)... Springs, FL (PRWEB) December 18, 2014 ... of the nation’s leading specialty pharmacies, has an ... serve as clinical pharmacy consultants for prescriber offices ... therapy expertise. , “We have a variety ... therapies. For example, those specializing in hepatitis C ...
(Date:12/19/2014)... Ed Bilsky, Ph.D., vice president for Research and ... the Neurosciences (CEN), and professor of pharmacology at the ... member of the prestigious Dana Alliance for Brain Initiatives ... receive this honor. , The Dana Alliance ... Foundation. Its mission is to advance public education ...
(Date:12/19/2014)... 2014 In contrast to traditional LED ... various colors, Valoya uses proprietary LED technology to incorporate ... possible uniformity which is critical in low proximity installations. ... accuracy throughout its lifetime which is up to four ... , "The investment cost was clearly higher when compared ...
(Date:12/19/2014)... BURLINGTON, Mass. , Dec. 18, 2014  Decision ... dental biomaterial market will grow moderately through ... implant procedures and growing awareness of dental biomaterials all ... underdeveloped markets such as China ... incomes will bring dental procedures within reach for a ...
Breaking Biology Technology:BioPlus Specialty Pharmacy Expands ‘Regional Pharmaceutical Care Liaison’ Team 2BioPlus Specialty Pharmacy Expands ‘Regional Pharmaceutical Care Liaison’ Team 3UNE's Ed Bilsky Named Member of Dana Alliance for Brain Initiatives 2UNE's Ed Bilsky Named Member of Dana Alliance for Brain Initiatives 3Asia Pacific Dental Biomaterial Market Will Grow Strongly Through 2023 2Asia Pacific Dental Biomaterial Market Will Grow Strongly Through 2023 3
... seems to defy gravity as it hovers with feathered ... the 2008 Olympus BioScapes Digital Imaging Competition, the world,s ... life science subjects. Mr. M. I. “Spike” Walker of ... of what is called a fairy fly, actually a ...
... a defense against the Black Plague, a disease that wiped ... and which government agencies perceive as a terrorist threat today. ... developed a vaccine that early research shows is highly effective ... and USDA funded research appear in the August edition of ...
... Ind. - Fingerprints can reveal critical evidence, as well ... technology developed at Purdue University that detects trace amounts ... the prints. , The new technology also can distinguish ... difficult task for current optical forensic methods. , A ...
Cached Biology Technology: It's a Bug's Life, as Flawless Photo of Wasp Wins Worldwide Olympus BioScapes Competition : Winning Sure Doesn't Sting - Olympus BioScapes 2008 Competition 2 It's a Bug's Life, as Flawless Photo of Wasp Wins Worldwide Olympus BioScapes Competition : Winning Sure Doesn't Sting - Olympus BioScapes 2008 Competition 3 It's a Bug's Life, as Flawless Photo of Wasp Wins Worldwide Olympus BioScapes Competition : Winning Sure Doesn't Sting - Olympus BioScapes 2008 Competition 4UCF professor develops vaccine to protect against black plague bioterror attack 2UCF professor develops vaccine to protect against black plague bioterror attack 3Fingerprints provide clues to more than just identity 2
(Date:12/3/2014)... GLENDALE, Ariz. , Dec. 2, 2014 ... biometric hand readers, Inception Technologies is pleased to announce ... it easier for customers to collect the workforce data ... the problems that have been left by existing readers. ... to user interface, connectivity and modern technology. Older models ...
(Date:11/21/2014)... Nov. 20, 2014 Strict laws against distracted ... piloting the North American and European automotive sector towards ... gesture recognition systems that are intuitive and able to ... the industry. New analysis from Frost ... Market in Europe and ...
(Date:11/18/2014)... , Nov. 18, 2014  The Secure Identity ... Association today jointly announce the formation of The ... of its Identity and Biometric Entry and ... Framework received official support from BORDERPOL, the international ... improve and provide expertise regarding border security, traveler ...
Breaking Biology News(10 mins):Inception Technologies to Release New Biometric Reader 2Gesture Recognition Intensifies with the Rise of In-car Smartphone Integration, Says Frost & Sullivan 2Gesture Recognition Intensifies with the Rise of In-car Smartphone Integration, Says Frost & Sullivan 3Gesture Recognition Intensifies with the Rise of In-car Smartphone Integration, Says Frost & Sullivan 4Identity Management, Document Authentication and Biometric Companies Form "The Airport Entry and Exit Working Group", Releasing the Framework to Help Guide the Department of Homeland Security and Congress Towards Solutions 2Identity Management, Document Authentication and Biometric Companies Form "The Airport Entry and Exit Working Group", Releasing the Framework to Help Guide the Department of Homeland Security and Congress Towards Solutions 3
... Standard Reference Material (SRM) from the National Institute of ... more accurately diagnose and treat cytomegalovirus (CMV), a common ... with weakened immune systems. CMV is found in ... a member of the herpes family of viruses that ...
... A review article by researchers at Boston University ... hypertension, or high blood pressure, is the result of ... pressure on the arteries. Published online in the ... salt stimulates the sympathetic nervous system to produce adrenalin, ...
... Of all the habitable parts of our planet, one ecosystem ... ocean crust. This rocky realm of hard volcanic lava ... much of the world,s oceans. While scientists have estimated ... much as one-third of Earth,s total biomass, the habitable portion ...
Cached Biology News:NIST standard available for better diagnosis, treatment of cytomegalovirus 2Boston University School of Medicine researchers clarify link between salt and hypertension 2Scientists look to microbes to unlock Earth's deep secrets 2
... Recognizes K+ Cl- Cotransporter-1 ... no significant sequence homology ... CCC.,SPECIES REACTIVITIES: The immunogen ... in human, mouse, porcine ...
...
Anti-G-alpha-i 1 G-Protein Host: mouse monoclonal Species Reactivity: human, mouse, rat Applications: WB Storage: 4C...
oligophrenin-1 (H-100)...
Biology Products: