Wednesday, August 30, 2006

'Nanocantilevers' yield surprises critical for designing new detectors

This rendition depicts an array of tiny, diving-boardlike devices called nanocantilevers. The devices are coated with antibodies to capture viruses, which are represented as red spheres. New findings about the behavior of the cantilevers could be crucial in designing a new class of ultra-small sensors for detecting viruses, bacteria and other pathogens. (Image generated by Seyet, LLC)This rendition depicts an array of tiny, diving-boardlike devices called nanocantilevers. The devices are coated with antibodies to capture viruses, which are represented as red spheres.
New findings about the behavior of the cantilevers could be crucial in designing a new class of ultra-small sensors for detecting viruses, bacteria and other pathogens. (Image generated by Seyet, LLC)
Nanocantilevers High Resolution Image.

WEST LAFAYETTE, Ind. — Researchers at Purdue University have made a discovery about the behavior of tiny structures called nanocantilevers that could be crucial in designing a new class of ultra-small sensors for detecting viruses, bacteria and other pathogens.

The nanocantilevers, which resemble tiny diving boards made of silicon, could be used in future detectors because they vibrate at different frequencies when contaminants stick to them, revealing the presence of dangerous substances. Because of the nanocantilever's minute size, it is more sensitive than larger devices, promising the development of advanced sensors that detect minute quantities of a contaminant to provide an early warning that a dangerous pathogen is present

The researchers were surprised to learn that the cantilevers, coated with antibodies to detect certain viruses, attract different densities — or quantity of antibodies per area — depending on the size of the cantilever. The devices are immersed into a liquid containing the antibodies to allow the proteins to stick to the cantilever surface.

"But instead of simply attracting more antibodies because they are longer, the longer cantilevers also contained a greater density of antibodies, which was very unexpected," said Rashid Bashir, a researcher at the Birck Nanotechnology Center and a professor of electrical and computer engineering and biomedical engineering at Purdue University. The research also shows that the density is greater toward the free end of the cantilevers.

The engineers found that the cantilevers vibrate faster after the antibody attachment if the devices have about the same nanometer-range thickness as the protein layer. Moreover, the longer the protein-coated nanocantilever, the faster the vibration, which could only be explained if the density of antibodies were to increase with increasing lengths, Bashir said. The research group also proved this hypothesis using optical measurements and then worked with Ashraf Alam, a researcher at the Birck Nanotechnology Center and professor of electrical and computer engineering, to develop a mathematical model that describes the behavior.

The information will be essential to properly design future "nanomechanical" sensors that use cantilevers, Bashir said.

Findings are detailed in a research paper appearing online today (Monday, Aug. 28) in Proceedings of the National Academy of Sciences. The paper was authored by Amit K. Gupta, a former Purdue doctoral student working with Bashir and now a postdoctoral researcher at Harvard University; Pradeep R. Nair, a doctoral student in electrical and computer engineering; Demir Akin, research assistant professor of biomedical engineering; Michael Ladisch, Distinguished Professor of Agricultural and Biological Engineering with a joint appointment in the Weldon School of Biomedical Engineering; Steven Broyles, a professor of biochemistry; Alam and Bashir.

The work, funded by the National Institutes of Health, is aimed at developing advanced sensors capable of detecting minute quantities of viruses, bacteria and other contaminants in air and fluids by coating the cantilevers with proteins, including antibodies that attract the contaminants. Such sensors will have applications in areas including environmental-health monitoring in hospitals and homeland security. So-called "lab-on-a-chip" technologies could make it possible to replace bulky lab equipment with miniature sensors, saving time, energy and materials. Thousands of the cantilevers can be fabricated on a 1-square-centimeter chip, Bashir said.

The cantilevers studied in the recent work range in length from a few microns to tens of microns, or millionths of a meter, and are about 20 nanometers thick, which is also roughly the thickness of the antibody coating. A nanometer is a billionth of a meter, or approximately the length of 10 hydrogen atoms strung together.

A cantilever naturally "resonates," or vibrates at a specific frequency, depending on its mass and mechanical properties. The mass changes when contaminants land on the devices, causing them to vibrate at a different "resonant frequency, " which can be quickly detected. Because certain proteins attract only specific contaminants, the change in vibration frequency means a particular contaminant is present.

Ordinarily, when using cantilevers that are on a thickness scale of microns or larger, attaching mass causes the resonant frequency to decrease, which is the opposite of what occurs with the nanoscale-thickness cantilevers. Researchers believe the unexpected behavior is a result of the antibodies being about the same thickness as the ultra-thin nanocantilevers, meaning their vibration is more profoundly affected than a more massive cantilever would be by the attachment of the antibodies.

"The conclusion is that when the attached mass is as thick as the cantilever, then you not only affect the mass but you also affect a key property called the net stiffness constant and the resonant frequency can actually go up," Bashir said.

Gupta measured the cantilever's vibration frequency using an instrument called a laser Doppler vibrometer, which detects changes in the cantilever's velocity as it vibrates. The researchers then treated the antibodies with a fluorescent dye and took images of the proteins on the cantilever's surface, proving that the density increases with longer cantilevers

Nair and Alam then developed a mathematical model to explain why the density increases as the area of the cantilever rises. The model uses a "diffusion reaction equation" to simulate the antibodies sticking to the cantilever's surface.

The research is based at the Birck Nanotechnology Center at Discovery Park, the university's hub for interdisciplinary research.

Writer Emil Venere, (765) 494-4709, venere@purdue.edu
Sources: Rashid Bashir, (765) 496-6229, bashir@ecn.purdue.edu
Amit Gupta, (765) 404-5141, agupta@ecn.purdue.edu
Ashraf Alam, (765) 494-5988, alam@purdue.edu
Purdue News Service: (765) 494-2096; purduenews@purdue.edu
Related Web site:Purdue Laboratory of Integrated Bio Medical Micro/Nanotechnology & Applications

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RELATED: Keywords Nanotech, science Sunday, August 27, 2006 ion pump cooling hot computer chips, Thursday, August 24, 2006 Honeycomb Network Comprised of Anthraquinone Molecules, Sunday, August 20, 2006 siRNA shrink ovarian cancer tumors, Wednesday, August 16, 2006 Nanotechnology

Sunday, August 27, 2006

ion pump cooling hot computer chips

Infrared images show how a new UW micro-pump cools a heated surface: (Top) The air pump is off. (Bottom) The air pump is on.Tiny ion pump sets new standard in cooling hot computer chips

University of Washington, Infrared images show how a new UW micro-pump cools a heated surface: (Top) The air pump is off. (Bottom) The air pump is on. highest resolution version of this photo (print ready).
University of Washington researchers have succeeded in building a cooling device tiny enough to fit on a computer chip that could work reliably and efficiently with the smallest microelectronic components.

The device, which uses an electrical charge to create a cooling air jet right at the surface of the chip, could be critical to advancing computer technology because future chips will be smaller, more tightly packed and are likely to run hotter than today's chips. As a result, tomorrow's computers will need cooling systems far more efficient than the fans and heat sinks that are used today.

"With this pump, we are able to integrate the entire cooling system right onto a chip," said Alexander Mamishev, associate professor of electrical engineering and principal investigator on the project. "That allows for cooling in applications and spaces where it just wasn't realistic to do before." The micro-pump also represents the first time that anyone has built a working device at this scale that uses this method, Mamishev added.

"The idea has been around for several years," he said. "But until now it hasn't been physically demonstrated in terms of a working prototype."

Mamishev and doctoral students Nels Jewell-Larsen and Chi-Peng Hsu presented a paper on the device at the American Institute of Aeronautics and Astronautics/American Society of Mechanical Engineers Joint Thermophysics and Heat Transfer Conference earlier this summer and are scheduled to give an additional presentation this fall. In addition, the UW researchers and collaborators with Kronos Advanced Technologies and Intel Corp. have been awarded a $100,000 grant from the Seattle-based Washington Technology Center for the second phase of the project.

The device utilizes an electrical field to accelerate air to speeds previously possible only with the use of traditional blowers. Trial runs showed that the prototype device significantly cooled an actively heated surface on just 0.6 watts of power.

The prototype cooling chip contains two basic components: an emitter and a collector. The emitter has a tip radius of about 1 micron – so small that up to 300 tips could fit across a human hair. The tip creates air ions, electrically charged particles that are propelled in an electric field to the collector surface. As the ions travel from tip to collector, they create an air jet that blows across the chip, taking heat with it. The volume of the airflow can be controlled by varying the voltage between the emitter and collector.

The findings are significant for future computing applications, which will incorporate denser circuitry to boost computing power. More circuitry equals more heat and a greater need for innovative cooling technologies that go beyond bulky, noisy and relatively inefficient fans and heat sinks – metal plates with fins to increase surface area and help dissipate heat. Circulating liquids among the chips to draw away heat is one possibility, but computer chips and liquids don't mix well; the cost of a cooling system breakdown could be steep.

"Our goal is to develop advanced cooling systems that can be built right onto next-generation microchips," Jewell-Larsen said. "Such systems could handle both the increased heat generation of future chips and the fact that they would be distributed throughout a computer or electronic device." Added Mamishev: "It promises a new dimension in thermal management strategy and design."

A few challenges remain, he added. One involves developing the mathematical models to control vast systems of chips with built-in coolers. "These pumps end up being very complicated, dynamic systems," Mamishev said. "You have flow on a microscale, electrohydrodynamic forces, electrical fields and moving charges."

A second challenge is identifying the best materials to use in building devices that are high-performing and durable. "There is evidence that nanotubes and other nano-structures could give significant performance gains," Jewell-Larsen said. "Those are avenues we are currently pursuing." ###

For more information, contact Mamishev at (206) 221-5729 or mamishev@ee.washington.edu
Contact: Rob Harrill rharrill@u.washington.edu 206-543-2580 University of Washington

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Thursday, August 24, 2006

Honeycomb Network Comprised of Anthraquinone Molecules

Molecules spontaneously form honeycomb network featuring pores of unprecedented size

UCR discovery of molecular self-assembly could help develop templates for growing complex structures on surfaces; improve paints and lubricants.

Caption: Anthraquinone molecules form chains of molecules that weave themselves into a sheet of hexagons on a polished copper surface. Credit: Ludwig Bartels's research group, UCR, Usage Restrictions: None.Caption: Anthraquinone molecules form chains of molecules that weave themselves into a sheet of hexagons on a polished copper surface. Credit: Ludwig Bartels's research group, UCR, Usage Restrictions: None.
Riverside, Calif. -- UC Riverside researchers have discovered a new way in which nature creates complex patterns: the assembly of molecules with no guidance from an outside source. Potential applications of the finding are paints, lubricants, medical implants, and processes where surface-patterning at the scale of molecules is desired.

Spreading anthraquinone, a common and inexpensive chemical, on to a flat copper surface, Greg Pawin, a chemistry graduate student working in the laboratory of Ludwig Bartels, associate professor of chemistry, observed the spontaneous formation of a two-dimensional honeycomb network comprised of anthraquinone molecules.

The finding, reported in the Aug. 18 issue of Science, describes a new mechanism by which complex patterns are generated at the nanoscale – 0.1 to 100 nanometers in size, a nanometer being a billionth of a meter – without any need for expensive processes such as lithography.

"We know that some of the most striking phenomena in nature, like the colors on a butterfly wing, come about by the regular arrangement of atoms and molecules," said Pawin, the first author of the paper. "But what physical and chemical processes guide their arrangement? Anthraquinone showed us how such patterns can form easily and spontaneously."

Over a span of several years, Bartels's research group tested a multitude of molecules for pattern formation at the nanoscale. The group found that, generally, these molecules tended to become lumps, forming uninteresting islands of molecules lying side by side.

Anthraquinone molecules, however, form chains that weave themselves into a sheet of hexagons on the copper surface, forming a network similar to chicken wire. The precise shape of the network is governed by a delicate balance between forces of attraction and repulsion operating on the molecules.

"The honeycomb pattern that the anthraquinone molecules produce is open, meaning it has big pores, or cavities, enclosed by the hexagonal rings," Pawin said. "Such patterns have never been observed before. Rather, the common belief was that they cannot be generated. But anthraquinone shows that we can use chemistry to engineer molecules that self-assemble into structures with pores that are many times larger than the individual molecules themselves. With judicious engineering of the relation between the strength of the attraction and repulsion, we could tailor film patterns and pore sizes almost at will."

Patterning of surfaces is important for many applications. The friction that water or air experience when flowing over a surface crucially depends on the microscopic structure of the surface. Biological cells and tissue grow easily on surfaces of some patterns while rejecting other patterns and completely flat surfaces.

In their research the UCR chemists first cleaned the copper surface, creating an extremely slippery surface. Then they deposited anthraquinone molecules onto it. Next, the surface with the molecules was annealed to spread the molecules. During cool-down to the temperature of liquid nitrogen, the hexagonal pattern emerged.

Pawin also developed a computer model to understand not only why the anthraquinone molecules lined up in rows that ultimately arranged themselves into a honeycomb network, but also how anthraquinone molecules are prevented from taking up space inside the pores.

"The precise pattern anthraquinone forms depends on a delicate balance between the attraction between the anthraquinone molecules and the substrate-mediated forces that ultimately disperse these molecules," said Bartels, a member of UCR's Center for Nanoscale Science and Engineering. "By fine-tuning this balance, it should be possible to produce a wide variety of patterns of different sizes."

In the future, Pawin and Bartels plan on investigating how chemical modifications of anthraquinone can produce novel patterns. "In addition, we would like to form the hexagonal network at higher temperatures and be able to control the size of the hexagons," Pawin said. "We also want to extend our research to include surfaces other than copper and determine if there are molecules similar to anthraquinone that assemble spontaneously into sheets on them."

Besides Pawin and Bartels, Kin L. Wong and Ki-Young Kwon of Bartels's research group participated in the study, which was supported by a grant from the National Science Foundation. Pawin first started working in Bartels's laboratory in 2000 as an undergraduate. This fall, he will be a second-year graduate student at UCR.

Details of the study

Anthraquinone molecules consist of three fused benzene rings with one oxygen atom on each side. An organic compound, anthraquinone is widely used in the pulp industry for turning cellulose from wood into paper. It is also the parent substance of a large class of dyes and pigments. Its chemical formula is C14H8O2.

The pore diameter of the honeycomb network of anthraquinone molecules is about 50 Å. The attractive interaction between the molecules stems from hydrogen bridge bonding, a phenomenon common in nature and fundamental to all life (e.g., by holding DNA helixes together) but which occurs here in a slightly unconventional and novel form. The substrate-meditated repulsive interactions are: (a) expansion of the copper surface because the anthraquinone molecules 'dig' their oxygen 'heels' into it; (b) electrostatic repulsion due to slightly negative charging of the anthraquinone molecules; or (c) a combination thereof.

The UCR study used a scanning tunneling microscope in Bartels's laboratory which can image individual molecules at great precision. An individual anthraquinone molecule appears as an almost rectangular feature with slightly rounded edges. The sides of each hexagon consist of three parallel anthraquinone molecules. The vertices consist of three anthraquinone molecules that form a triangle. Each hexagon encloses more than 200 atoms of the copper substrate. ###

Link of the MOVIE eurekalert.org/pawin_anthrahex.mov

The University of California, Riverside is a major research institution. Key areas of research include nanotechnology, health science, genomics, environmental studies, digital arts and sustainable growth and development. With a current undergraduate and graduate enrollment of more than 16,600, the campus is projected to grow to 21,000 students by 2010. Located in the heart of Inland Southern California, the nearly 1,200-acre, park-like campus is at the center of the region's economic development. Visit ucr.edu/ or call 951-UCR-NEWS for more information. Media sources are available at mediasources.ucr.edu/.

Contact: Iqbal Pittalwala iqbal@ucr.edu 951-827-6050 University of California - Riverside

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RELATED: Keywords Nanotech, science Sunday, August 20, 2006 siRNA shrink ovarian cancer tumors, Wednesday, August 16, 2006 Nanotechnology

Sunday, August 20, 2006

siRNA shrink ovarian cancer tumors

The University of Texas M.D. Anderson Cancer Center LogoFatty spheres loaded with siRNA shrink ovarian cancer tumors in preclinical trial,
Nanoparticles slip through blood vessel pores to attack tumor.

(HOUSTON) -- A molecular "off" switch packaged in a tiny sphere penetrates deeply into ovarian cancer tumor cells, stifling a troublesome protein and drastically reducing the size of tumors, researchers at The University of Texas M. D. Anderson Cancer Center report in the Aug. 15 edition of Clinical Cancer Research.

The mouse model experiment, featured on the cover of the journal, demonstrates a potent delivery system for short interfering RNA (siRNA) to attack cancer, says senior author Anil Sood, M.D., associate professor in the Departments of Gynecologic Oncology and Cancer Biology at M. D. Anderson.

"Short interfering RNA is a great technology we can use to silence genes, shutting down production of harmful proteins," Sood says. "It works well in the lab, but the question has been how to get it into tumors." Short pieces of RNA don't make it to a tumor without being injected directly, and injection methods used in the lab are not practical for clinical use.

The research team took siRNA that targets a protein that helps ovarian cancer cells survive and spread and rolled it into a liposome -- a lipid ball so small that its dimensions are measured in nanometers (billionths of a meter).

Getting the siRNA inside tumor cells is important, Sood said, because the targeted protein, focal adhesion kinase (FAK), is inside the cell, rather than on the cell surface where most proteins targeted by cancer drugs are found. "Targets like FAK, which are difficult to target with a drug, can be attacked with this liposomal siRNA approach, which penetrates deeply into the tumor," Sood said.

Mice infected with three human ovarian cancer cell lines derived from women with advanced cancer were treated for 3-5 weeks. They received liposomes that contained either the FAK siRNA, a control siRNA, or were empty. Some mice received siRNA liposomes plus the chemotherapy docetaxel.

Mice receiving the FAK-silencing liposome had reductions in mean tumor weight ranging from 44 to 72 percent compared with mice in the control groups. Combining the FAK-silencing liposome with docetaxel boosted tumor weight reduction to the 94-98 percent range.

These results also held up in experiments with ovarian cancer cell lines resistant to docetaxel and to the chemotherapy drug cisplatin.

The FAK-silencing liposome and the liposome with chemotherapy also reduced the incidence of cancer by between 20 and 50 percent in all tested cancer lines.

In addition to its anti-tumor effect, the researchers found that the therapeutic liposome attacked the tumor's blood supply, especially when combined with chemotherapy. By inducing cell suicide (apoptosis) among blood vessel cells, the treatment steeply reduced the number of small blood vessels feeding the tumor, cut the percentage of proliferating tumor cells and increased cell suicide among cancer cells.

Sood and Professor of Molecular Therapeutics Gabriel Lopez-Berestein, M.D., an expert in liposomal therapeutics, cite at least two factors for the success of the anti-FAK liposome.

"This particle is so small, it has no problem getting through the tumor's vasculature and into the tumor," Lopez-Berestein says. The FAK-targeting liposome ranges between 65 and 125 nanometers in diameter. Blood vessels that serve tumors are more porous than normal blood vessels, with pores of 100 to 780 nanometers wide. Normal blood vessel pores are 2 nanometers or less in diameter.

Second, the liposome -- a commercially available version known as DOPC -- has no electrical charge. Its neutrality provides an advantage over positively or negatively charged liposomes when it comes to binding with and penetrating cells.

The next step for the FAK siRNA-DOPC liposome is toxicity testing. "So far it appears to be very well-tolerated," Sood says. "We hope to develop this approach for clinical use in the future."

In addition to ovarian cancer, FAK is overexpressed in colon, breast, thyroid, and head and neck cancers. ###

Co-authors with Sood and Lopez-Berestein are first author Jyotsnabaran Halder, Ph.D., Aparna Kamat, M.D., Charles Landen, M.D., Liz Han, M.D., Yvonne Lin, William Merritt, Nicholas Jennings, Robert Coleman, M.D., David Gershenson, M.D., and Rosemarie Schmandt, Ph.D., all of the Department of Gynecologic Oncology at M. D. Anderson; Arturo Chavez-Reyes of the Department of Experimental Therapeutics at M. D. Anderson; and Susan Lutgendorf, Ph.D., and Steven Cole, Ph.D., of the Department of Medical Hematology Oncology at UCLA.

Contact: Scott Merville sdmervil@mdanderson.org 713-792-0661 University of Texas M. D. Anderson Cancer Center

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Wednesday, August 16, 2006

Nanotechnology

The U.S. National Nanotechnology Initiative uses the term "nanotechnology" to describe:

Research and technology development aimed to work at atomic and molecular scales, in the length scale of approximately 1 - 100 nanometer range;

The ability to understand, create and use structures, devices and systems that have fundamentally new properties and functions because of their nanoscale structure;

The ability to control – to see, measure and manipulate – matter on the atomic scale to exploit those properties and functions.

Sunday, August 13, 2006

GALLERY

Infrared images show how a new UW micro-pump cools a heated surface: (Top) The air pump is off. (Bottom) The air pump is on.University of Washington, Infrared images show how a new UW micro-pump cools a heated surface: (Top) The air pump is off. (Bottom) The air pump is on. highest resolution version of this photo (print ready).
Tiny ion pump sets new standard in cooling hot computer chips FULL TEXT, ion pump cooling hot computer chips.

Caption: Anthraquinone molecules form chains of molecules that weave themselves into a sheet of hexagons on a polished copper surface. Credit: Ludwig Bartels's research group, UCR, Usage Restrictions: None.Caption: Anthraquinone molecules form chains of molecules that weave themselves into a sheet of hexagons on a polished copper surface. Credit: Ludwig Bartels's research group, UCR, Usage Restrictions: None.
FULL TEXT, Honeycomb Network Comprised of Anthraquinone Molecules, Molecules spontaneously form honeycomb network featuring pores of unprecedented size

This rendition depicts an array of tiny, diving-boardlike devices called nanocantilevers. The devices are coated with antibodies to capture viruses, which are represented as red spheres. New findings about the behavior of the cantilevers could be crucial in designing a new class of ultra-small sensors for detecting viruses, bacteria and other pathogens. (Image generated by Seyet, LLC)This rendition depicts an array of tiny, diving-boardlike devices called nanocantilevers. The devices are coated with antibodies to capture viruses, which are represented as red spheres.
New findings about the behavior of the cantilevers could be crucial in designing a new class of ultra-small sensors for detecting viruses, bacteria and other pathogens. (Image generated by Seyet, LLC)
Nanocantilevers High Resolution Image. FULL TEXT 'Nanocantilevers' yield surprises critical for designing new detectors.

This false-color image shows a cell from the epidermis of an Arabidopsis thaliana plant; the cell has been marked with fluorescent imaging sensors designed to detect the sugar glucose. In this image, only the densely packed interior of the cell in which most metabolic functions occur—called the cytosol—is targeted by the glucose sensors. The dark area sits inside the vacuole—a large storage organelle that can occupy up to 90% of the cell’s volume. (Image courtesy Sylvie Lalonde and Wolf Frommer;)This false-color image shows a cell from the epidermis of an Arabidopsis thaliana plant; the cell has been marked with fluorescent imaging sensors designed to detect the sugar glucose.
In this image, only the densely packed interior of the cell in which most metabolic functions occur—called the cytosol—is targeted by the glucose sensors. The dark area sits inside the vacuole—a large storage organelle that can occupy up to 90% of the cell’s volume. (Image courtesy Sylvie Lalonde and Wolf Frommer; click for higher resolution.) FULL TEXT Sugar metabolism tracked in living plant tissues, in real time.

Scientists used a scanning tunneling microscope to manipulate chlorophyll-a into four positions. art by: Saw-Wai HlaNanoscientists Create Biological Switch from Spinach Molecule, Scientists used a scanning tunneling microscope to manipulate chlorophyll-a into four positions. art by: Saw-Wai Hla, Tuesday Sep 05, 2006, by Andrea Gibson. FULL TEXT Nanoscientists Create Biological Switch from Spinach Molecule

Jamie Mullally '07, right, a Cornell Presidential Research Scholar, and Margaret Frey, assistant professor of textiles and apparel, examine a nonwoven nanofiber fabric on aluminum foil backing. Mullally will complete an honors thesis on the biorecognition fabrics in spring '07. Copyright © Cornell UniversityJamie Mullally '07, right, a Cornell Presidential Research Scholar, and Margaret Frey, assistant professor of textiles and apparel, examine a nonwoven nanofiber fabric on aluminum foil backing. Mullally will complete an honors thesis on the biorecognition fabrics in spring '07. Copyright © Cornell University. FULL TEXT, Biodegradable napkin, featuring nanofibers, may detect biohazards

Nanoscale metallic electrodes (in yellow) can be used to confine electrons in small regions, forming quantum dots. Two quantum dots connected to each other form a double quantum dot. In this case, one of the dots is in the Kondo state, in which the magnetic moment of the confined electron (large red arrow) is compensated ('screened') by the magnetic moment of surrounding electrons, resulting in a zero net magnetic moment for the entire system. art by: Luis Dias/Ohio UniversityNanoscale metallic electrodes (in yellow) can be used to confine electrons in small regions, forming quantum dots. Two quantum dots connected to each other form a double quantum dot.
In this case, one of the dots is in the Kondo state, in which the magnetic moment of the confined electron (large red arrow) is compensated (“screened”) by the magnetic moment of surrounding electrons, resulting in a zero net magnetic moment for the entire system. art by: Luis Dias/Ohio University. FULL TEXT, Double Quantum Dots Control Kondo Effect

MIT researchers have discovered that certain molecules can attach themselves to metallic carbon nanotubes without interfering with the nanotubes' exceptional ability to conduct electricity. At left, the high conductance state has two molecular orbitals, shown in green. Some molecules even let the nanotube switch between highly conductive, left, and poorly conductive (right, with one red molecular orbital), creating the potential for new applications. Image courtesy / Marzari Lab.Based on a new theory, MIT scientists may be able to manipulate carbon nanotubes --
one of the strongest known materials and one of the trickiest to work with -- without destroying their extraordinary electrical properties. FULL TEXT, scientists tame tricky carbon nanotubes

Title: Motorized Nanocar, Credit: Yasuhiro Shirai/Rice UniversityThis animation depicts two motorized nanocars on a gold surface. The nanocar consists of a rigid chassis and four alkyne axles that spin freely
and swivel independently of one another. The wheels are spherical molecules of carbon, hydrogen and boron called p-carborane. FULL TEXT, Nanocar inventor named top nanotech innovator

Caption: In NIST's Einstein-de Haas experiment, the movements of a cantilever were measured with an optical-fiber laser interferometer. The optical fiber is 125 micrometers in diameter, and the end is positioned less than 10 micrometers from the cantilever surface. Credit: Credit: John Moreland/NIST, Usage Restrictions: None.Caption: In NIST's Einstein-de Haas experiment.
the movements of a cantilever were measured with an optical-fiber laser interferometer, The optical fiber is 125 micrometers in diameter, and the end is positioned less than 10 micrometers from the cantilever surface. Credit: Credit: John Moreland/NIST, Usage Restrictions: None. FULL TEXT, Einstein's magnetic effect is measured on microscale