Going to buy a used car!!!

As is known, it's really inconvenient to live without a car in USA. I just want to do some "homework" on how to buy a used car from the internet!

Here within is some related Ref:

With economics a major problem, used cars have become great alternatives to people who do not have much to spare in the financial area. Finding used cars is not really a problem as there are thousands of used cars outlets in the country. Buyers of used cars will, in fact, have a wide range of models and brands to choose from.But as these cars are already well used, it is important for buyers to understand the dynamics of buying a used car to ensure that they are getting value for their money.

Here are some tips that any buyer can take heart whether they are buying used or brand new automobiles.

Scout for the perfect deal The principle of collect and collect, then select also applies in buying a used car. Remember that used car outlets need you more than you need them, so make the most of this special privilege and look not only for the better but for the best car and the best deal.

Used car outlets, in fact, have special promos and deals that you can avail of. Some offer discounts, rebates and even installment payments while others opt for free services like changing of tire or cleaning.

Wait up for a good deal. For though you are not paying full price for the car, you still deserve quality from the payment that you are going to make. After all, whether it is brand new or a car already used, it will still put a huge dent on your budget. So you better make the most out of every penny that you will be shelling out.

Give yourself time When buying or scouting for a used car, it is important that you give yourself ample time to look for one. Otherwise you will only end up buying a used car that you will not be using after a couple of months.

Giving yourself no time to decide and choose will only make you settle for a used car that is not really what you are looking for. This may be well and good for a brand new car because at least with a new one, you will not have to think about the wear and tear. Buying a used car in a hurry is suicide in more ways than one, because you are also compromising your safety when you choose in haste.

Be aware of the lemon law in your state The Lemon Law covers both used and brand new cars. While different states have different policies for used cars under the Lemon Law, basically, it gives you the same coverage. If you find that a used car is sold to you under false pretenses or did not function the way it was supposed to function in accordance to the guidelines, you have the right as a consumer to invoke the Lemon Law.

Buy from a friend Buying a used car from friends who you know is way better than buying used cars sold in shops. For unless you have an eye for quality used car, you might end up buying a junk that you will not be able to use in the long run. If you know people who are selling their used cars at lower costs not because the cars are already worn but because they are buying new models, thats better. Its better to buy the used cars from private individuals because in a way you know how the car was used.

Ask for referrals It is also a good idea to ask the help of people who have already bought used cars, as they will be able to guide you with the entire procedure as well as refer you to the right store and person that can help you choose a quality used car. They can also refer you to a reputable used car store that they have already tried. This way, you can be assured of the quality of product and service.

Dont be afraid to ask your friends, relatives or colleagues at work. Youll find that they are more than willing to help someone. After all, nothing boosts the ego than the thought that they can be experts in one subject.

Silicon Nanowires Upgrade Data-Storage Technology

Scientists at the National Institute of Standards and Technology (NIST), along with colleagues at George Mason University and Kwangwoon University in Korea, have fabricated a memory device that combines silicon nanowires with a more traditional type of data-storage. Their hybrid structure may be more reliable than other nanowire-based memory devices recently built and more easily integrated into commercial applications.

Centered is a photo of a ZnO nanowire array on a 4 inch silicon wafer. It is surrounded by images of the array at different locations and magnifications. Scale bars, clockwise from upper left, correspond to 2 µm, 500 nm, 200 nm, and 1µm.

As reported in a recent paper,* the device is a type of “non-volatile” memory, meaning stored information is not lost when the device is without power. So-called “flash” memory (used in digital camera memory cards, USB memory sticks, etc.) is a well-known example of electronic non-volatile memory. In this new device, nanowires are integrated with a higher-end type of non-volatile memory that is similar to flash, a layered structure known as semiconductor-oxide-nitride-oxide-semiconductor (SONOS) technology. The nanowires are positioned using a hands-off self-alignment technique, which could allow the production cost—and therefore the overall cost—of large-scale viable devices to be lower than flash memory cards, which require more complicated fabrication methods.

The researchers grew the nanowires onto a layered oxide-nitride-oxide substrate. Applying a positive voltage across the wires causes electrons in the wires to tunnel down into the substrate, charging it. A negative voltage causes the electrons to tunnel back up into the wires. This process is the key to the device’s memory function: when fully charged, each nanowire device stores a single bit of information, either a “0” or a “1” depending on the position of the electrons. When no voltage is present, the stored information can be read.

The device combines the excellent electronic properties of nanowires with established technology, and thus has several characteristics that make it very promising for applications in non-volatile memory. For example, it has simple read, write, and erase capabilities. It boasts a large memory window—the voltage range over which it stores information—which indicates good memory retention and a high resistance to disturbances from outside voltages. The device also has a large on/off current ratio, a property that allows the circuit to clearly distinguish between the “0” and “1” states.

Two advantages the NIST design may hold over alternative proposals for nanowire-based memory devices, the researchers say, are better stability at higher temperatures and easier integration into existing chip fabrication technology.

* Q. Li, X. Zhu, H. Xiong, S.-M. Koo, D.E. Ioannou, J. Kopanski, J.S. Suehle and C.A. Richter. Silicon nanowire on oxide/nitride/oxide for memory application. Nanotechnology 18 (2007) 235204.

Contact: Michael E. Newman michael.newman@nist.gov 301-975-3025 National Institute of Standards and Technology (NIST)

Image Credit: COPYRIGHT STATUS: LBNL (Lawrence Berkeley National Laboratory) authored documents are sponsored by the U.S. Department of Energy under Contract DE-AC02-05CH11231. Accordingly, the U.S. Government retains a nonexclusive, royalty-free license to publish or reproduce these documents, or allow others to do so, for U.S. Government purposes.

These documents may be freely distributed and used for non-commercial, scientific and educational purposes. Commercial use of the documents available from this server may be protected under the U.S. and Foreign Copyright Laws.

Merry Christmas!

It's really exciting to have a good travel to Napa and San Francisco this Christmas. The unforgetable Golden Gate Bridge, Twin Peaks, Bay Bridge Pier, Pier 39 (Fisherman's wharf), City Hall, ChinaTown... scene, the dilicious Chinese cuisine food are still clear in my mind. 3 busy days, a close to the U.S. culture and big city life.


After that, I have to shoot with the NSF left by Prof. Shen and the whole day long. Just feel so tired about it!!!

Better Body Armor Expected from New Material Formation Process Developed at Georgia Tech

Professor Robert Speyer and his research team have created a new boron carbide formation process. The method yields higher relative densities -- thus better ballistic performance -- than currently available boron carbide armor. Here, Speyer holds a prototype thigh plate.

A Georgia Institute of Technology researcher has developed a process that increases the hardness and improves the ballistic performance of the material used by the U.S. military for body armor. The researcher's start-up company is commercializing the technology.

Boron carbide is the Defense Department’s material of choice for body armor. It is the third hardest material on earth, yet it’s extremely lightweight. But it has an Achilles heel that piqued the interest of Georgia Tech Professor of Materials Science and Engineering Robert Speyer five years ago.

He knew that the boron carbide powder used to form the armor had a reputation for poor performance during sintering -- a high-temperature process in which particles consolidate, without melting, to eliminate pores between them in the solid state. Poor sintering yields a more porous material that fractures more easily – not a good thing for a soldier depending on it to stop a bullet.

Determined to understand the sintering problem, Speyer built an instrument called a differential dilatometer to measure the expansion and contraction of materials during sintering heat treatments to temperatures as high as 4,300 degrees Fahrenheit.

“As a particle compact sinters, it shrinks 12 to 15 percent,” Speyer explained. “There are nuances that occur in contraction, and if you monitor them accurately (with a dilatometer), it tells you what is happening at different stages in the sintering process. So we used that information in conjunction with additional materials characterization techniques to figure out the reasons why boron carbide didn’t sinter well, and then found ways around them.”

From these findings, Speyer and his research team have created a new boron carbide formation process based on methodical control of thermal and atmospheric conditions during sintering. The method yields higher relative densities – and thus better ballistic performance – than currently available boron carbide armor.(Relative density is a percentage that indicates how close a material is to its theoretical density, which implies having no pores.)

A new boron carbide formation process allows for the creation of complicated, curved shapes for use in helmets and other body armor. Here, a small-scale prototype helmet is shown.

The research has been reported in the Journal of Materials Research.

The current commercial process, called hot pressing, squeezes boron carbide powders together between large dies, while heating to elevated temperatures. It yields armor materials with a 98.1 percent relative density.

Speyer’s pressureless sintering method yields a 98.4 percent relative density and hardness greater than hot pressing. But it can be done faster and at a lower cost than hot pressing. For the most demanding applications, post-sintering hot isostatic pressing (HIP) is used. It increases the relative density of the part to 100 percent through the hydrostatic squeezing action of a high-temperature, high-pressure gas.

“Our material made using HIP is remarkably harder than the current ceramic armor used in the Iraq and Afghanistan theaters,” Speyer said. “Plus, because we’re not using uni-axial hot pressing, we can make complicated, curved shapes for use in form-fitting body armor and other applications. Hot pressing allows for some curvature so long as the parts can stack together, but there’s no chance of making parts like a single-piece helmet.”

A new boron carbide formation process allows for the creation of complicated, curved shapes. Here, a nozzle made from the material is shown.

To make such products, Speyer has formed a company called Verco Materials under the advisory support of Georgia Tech’s VentureLab, which helps faculty members commercialize their research. Ceramics expert Beth Judson is the company’s general manager, and Jon Goldman is the VentureLab commercialization catalyst helping Verco get started. A Georgia Tech patent on Speyer’s sintering process for boron carbide
is pending, and when granted, Verco will have access to an exclusive license, Judson said.

The company has received two technology commercialization grants – totaling $100,000 -- from the Georgia Research Alliance to fabricate prototypes for potential military and industrial customers. The Georgia Tech Rapid Prototyping and Manufacturing Institute assisted with fabrication of model armor shapes. Also, VentureLab continues to analyze the company’s potential markets.

Beyond body armor, potential military applications include aircraft/rotorcraft protective components. Civilian markets include industries “that can exploit the phenomenal abrasion resistance of theoretically dense boron carbide,” Speyer said.

The micrograph on the left depicts the historically typical porous microstructure of pressureless sintered boron carbide. At right is a theoretically dense boron carbide microstructure that was pressureless-sintered and post-hot isostatic pressed based on research by Professor Robert Speyer.

Products manufactured by these industries include bearings, blast nozzles, cutting and mining tools, and pump and turbine shafts. The military market is growing rapidly with more than a half billion dollars worth of ceramic armor orders pending in this fiscal year, Goldman noted. That market is expected to double by 2009, according to a recent report in the publication Ceramic Industry. Bearings are a $27 million market with 5.7 percent annual growth expected through 2007.

Military applications – body armor, in particular – would be Verco’s first target market, and its potential is promising, Speyer noted. The U.S. Army Soldier Systems Center in Natick, Mass., has conducted ballistic testing on a small boron carbide disk provided by Verco. Detailed results are classified, but the Army says they are encouraging. With a $75,000 grant from the center, Verco will produce 6- by 6-inch plates for more comprehensive military ballistic testing within the next few months.

Early next year, the Army Research Laboratory (ARL) at the Aberdeen Proving Ground in Maryland will be examining boron carbide materials (including complex shapes) they purchased from Verco. ARL is interested in Verco’s potential ability to form complex shapes cost effectively.

Meanwhile, Verco expects to make thigh and shin plate prototypes in early 2006 for a Johnstown, Penn., company called Concurrent Technologies Corporation (CTC). The plates will be evaluated for use in CTC’s Ballistic Gauntlet, a new lower-body armor product for use in military and commercial vehicles in war zones to protect against the pervasive threat of improvised explosive devices. It was the idea of CTC engineer Scott Burk, who recently served in the Persian Gulf for 21 months.

The company’s current design calls for the Ballistic Gauntlet’s thigh and shin plates to be made from titanium, but its cost has risen recently, and it’s hard to form and heavier than boron carbide, Judson and Goldman said.

In one other effort, Verco and the Georgia Tech Research Institute (GTRI) are collaborating. GTRI has developed a composite armor “blast bucket” for the ULTRA AP, a concept vehicle designed to illustrate potential technology options for improving survivability and mobility in future military combat vehicles. Verco and GTRI hope to modify the “blast bucket” by replacing heavier ceramic spheres with lightweight boron carbide spheres in the composite structure to make it attractive for use in new helicopters, as well as in retrofitting current rotorcraft, Judson said.

If Verco gets initial defense-related contracts from the customers it is courting, the company would need a tremendous productive capacity – enough to make thousands of parts a week, Judson and Goldman said. Plans call for a highly automated manufacturing facility in Georgia that would initially hire a significant number of engineering and manufacturing employees.

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Porous Bio-ceramics

Preparation of porous inorganic solids

Dr. Dominic Walsh (Email: d.walsh@bristol.ac.uk)

His research is centered around the preparation and development of porous inorganic structures suitable for use as implant materials such as artificial bones and teeth, as supports for drug delivery or as catalysts or catalyst supports. Previously he had employed various approaches to the preparation of these materials including the use of crystal altering additives in solution, microemulsions, carbonated water systems or other gas releasing reactions or sacrificial dextran templates. This research has included collaborations with NIMS Institute in Tsukuba, Japan, with the NCCR Institute, Osaka, Japan, the University of Bologna, Italy and the Orthopaedics Unit at Southampton University.

Some specific highlights in the research include the preparation of calcium phosphate bone mimic reticulated structures by the mineralization of water channels within a water/oil continuous microemulsion. Porous calcium carbonate spherical sponges were also prepared from mineralizing emulsion system and this system was also used to prepare hollow spherical clay structures. More recently metallic silver and gold foams were formed from dextran/metal salt mixtures that were heated to remove the organic component. A development of this principle was the preparation of frameworks of zeolite crystals contained within interlocked silica fibres. More recently sponge films of tricalcium phosphate bioceramic were prepared by a controlled precipitation at the air/water interface from a carbonated water mineralizing system.

Currently, as an EPSRC Advanced Research Fellow he is investigating the use of cold isotatic presssing (CIP) for the preparation of bioceramic tissue scaffolds suitable for cell seeding and also the preparation of catalysts and catalyst supports with an application in fuel cells. Overal CIP is a novel approach and suitable for scaling up for large scale production.

Busy day!

It is really A tired day today.

It's raining so heavy in the morning. When I went to the lab, it was 11:00 a.m. Coz I am going to meet with Doc. from N, so I have to prepare for the sample and try my best to polish the samples and make them look beautiful. But when I got one of the sample from the graphite die, I didn't pay more attention of the temperature and burn my 3 inculpable fingers. I didn't know what drives me so much to let me work so hard here. But I did the polishing for nearly 2 h thereafter.

Then I did 2 SPS sintering with Rustin. I contacted the furnace which could be used to do the sintering of the powder in Munir's group and Kim's group. Finally, a tube furnace was available only after Jan.7, 2008.

I hardly had time to eat my lunch today. I only had the lunch at 4:00.

In the evening, I did the Auto-polishing of the SPSed SiAlON sample and had more time to liberate myself.

Must have a good sleep tonight!

Happy day!

Weather today is cloudy but my heart is shining all day long.

Creative ideas must go first!!!

I am looking forward to more achievements in the near future!

Fantastic Ceramic Microstructure

Microstructure of a gas-pressure sintered silicon nitride. Their property profile is perfect:

• Extremely high strength
• Good crack resistance
• Outstanding wear resistance
• Good heat conductivity
• Very low heat expansion
• Good resistance to sudden changes in temperature

Fractured surface of Si3N4 and AlN

A conventional atomic resolution brightfield image created by imaging a sample of Silicon Nitride (Si3N4) with a transmission electron microscope.

By using the QPI algorithm an atomic resolution phase image can be created. Back propagatingthis phase image to the sample exit surface yields the view seen in the upper half of thisimage. The phase corresponding to the minimum amplitude variation is shown in the lowerhalf, where some of the Silicon (red) and Nitrogen (green) atoms have been indicated.

TEM micrograph of the silicon nitride ceramic powder.

Design Gadget--Ceramic Mobile

Ceramic Mobile - concept, Nokia and Arabia Finland, 2004

A mobile phone that challenges preconceived ideas of the properties and applications of ceramics today126 x 46 x 16 mm - zirconia (extremely tough), PC, F96 ceramic (reduces radiation exposure towards user).

May challenge this great new idea in China which country is famous for its long history on ceramic process.

New Blog, New Starting

To fulfill the international demands for communication and concerned the extra-large function of GOOGLE, I DECIDED to upgrade my blog to GOOGLE BLOG today!!!

New Blog: http://ucfchen.blogspot.com/
New E-mail: chenfei027@gmail.com ucfchen@ucdavis.edu

New blog has some merits like:

1. More friendly, more beautiful appearance, more professional;
2. Original photos with high resolution are available;
3. Easy to translate to other languages by using the GOOGLE translation system;
4. Helpful for enhancing and enlarging the international force.