March 7: 1876 : Alexander Graham Bell patents the telephone



On this day in 1876, 29-year-old Alexander Graham Bell receives a patent for his revolutionary new invention–the telephone.

The Scottish-born Bell worked in London with his father, Melville Bell, who developed Visible Speech, a written system used to teach speaking to the deaf. In the 1870s, the Bells moved to Boston, Massachusetts, where the younger Bell found work as a teacher at the Pemberton Avenue School for the Deaf. He later married one of his students, Mabel Hubbard.

While in Boston, Bell became very interested in the possibility of transmitting speech over wires. Samuel F.B. Morse’s invention of the telegraph in 1843 had made nearly instantaneous communication possible between two distant points. The drawback of the telegraph, however, was that it still required hand-delivery of messages between telegraph stations and recipients, and only one message could be transmitted at a time. Bell wanted to improve on this by creating a “harmonic telegraph,” a device that combined aspects of the telegraph and record player to allow individuals to speak to each other from a distance.



With the help of Thomas A. Watson, a Boston machine shop employee, Bell developed a prototype. In this first telephone, sound waves caused an electric current to vary in intensity and frequency, causing a thin, soft iron plate–called the diaphragm–to vibrate. These vibrations were transferred magnetically to another wire connected to a diaphragm in another, distant instrument. When that diaphragm vibrated, the original sound would be replicated in the ear of the receiving instrument. Three days after filing the patent, the telephone carried its first intelligible message–the famous “Mr. Watson, come here, I need you”–from Bell to his assistant.

Bell’s patent filing beat a similar claim by Elisha Gray by only two hours. Not wanting to be shut out of the communications market, Western Union Telegraph Company employed Gray and fellow inventor Thomas A. Edison to develop their own telephone technology. Bell sued, and the case went all the way to the U.S. Supreme Court, which upheld Bell’s patent rights. In the years to come, the Bell Company withstood repeated legal challenges to emerge as the massive American Telephone and Telegraph (AT&T) and form the foundation of the modern telecommunications industry.

Sourced and published by Henry Sapiecha 11th March 2010


All-solid Li-polymer Battery Goes

Flexible, Slim

2010 21:39 Tetsuo Nozawa, Nikkei Electronics

Mie Industry Enterprise Support Center (MIESC) announced that it prototyped a “sheet-type all-solid polymer lithium storage battery” by using only printing processes.

The battery is safe, thin, flexible and large in area, MIESC said. It will be exhibited at the 1st Int’l Rechargeable Battery Expo, which will take place from March 3 to 5, 2010, in Tokyo.

The positive electrode layer, electrolyte layer and negative electrode layer of the lithium-ion battery are made by roll-to-roll processes. No separator is used between layers.

The positive electrode is made with LiFePO4 and a carbon complex while the negative electrode is made with Li4Ti5O12 and a complex of graphite, silicon, etc. A film made of a polymer material using a cross-linked polyethylene oxide is used for the electrolyte.

The polymer material is not in a gel state but in a solid state, and the battery does not use an organic electrolyte, which is flammable, ensuring high safety.

The A6-size lithium-ion battery is 450?m in thickness. Its initial capacity is 45mAh. When half of the capacity is discharged, its voltage is 1.8V. The discharge rate can be changed between 0.02C and 1.0C.

Existing all-solid lithium polymer storage batteries can hardly be used at a room temperature or below. But the new battery can be used even at a temperature from 0 to 25°C, MIESC said. The charge-discharge cycle is more than 100 and is still being evaluated, it said.

Sourced and published by Henry Sapiecha 4th March 2010

Thermal Analysis of Foods

sugar-spoon

Foods usually have complex compositions and are subjected to many changes in temperature during production, transport, storage and processing. Pasteurization, sterilization, cooking and freezing are only some examples of such processes. Along with the factors of time and water content, temperature changes can have a decisive impact on the quality of foods.

Many substances are metastable and undergo phase changes during storage. Chemical reactions such as hydrolysis or oxidation can change color, appearance, or texture, or can even cause foods to become inedible. A good understanding of the effect of temperature changes on the physical and chemical properties of foods is therefore important for manufacturers in order to be able to optimize processing conditions and improve product quality.

Various Thermal Analysis methods, primarily Differential Scanning Calorimetry (DSC) and Thermogravimetry (TG) but also Dynamic-Mechanical Analysis (DMA), yield meaningful results for the evaluation of foods and their raw ingredients. NETZSCH-Gerätebau GmbH, a renowned manufacturer of instruments for Thermal Analysis and for the determination of thermophysical properties, provides equipment for all of the techniques needed for a comprehensive characterization.

thermal-analyser

For example, the specific heat (cp) indicates the amount of heat energy which must be supplied to or removed from a unit quantity of substance in order to change its temperature by one degree centigrade. This makes the specific heat to an extremely important parameter in the drafting of cooling, freezing, or heating procedures.
Some biological materials, as well as some spray-dried, ground or frozen substances, are amorphous; in other words, thermodynamically they are in a state of non-equilibrium.

This is characterized by a so-called glass transition, the temperature position of which is a function of several factors including the water content. Associated temperature-dependent phase changes can thereby cause powders to become sticky, affect the crispness of breakfast cereals or cause gelled starches to crystallize.

Sourced and published by Henry Sapiecha 18th October 2009

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OPTICAL MOLECULAR

IMAGING:

In vivo commercial systems

heighten appeal of molecular

imaging

brain-scan-pic-in-colour

Last November, the Cleveland Clinic (Cleveland, OH) ranked an optical molecular imaging system as one of the year’s top ten medical innovations. “We believe this technology to be a game changer,” said Jennifer Hunt, the clinic’s head of surgical pathology. “When we’re talking about tumors, we’re talking about what information we can gain about that tumor to guide and direct therapy, prognosis, and diagnostics,” she said, referring to the clinic’s use of the Nuance system by Cambridge Research & Instrumentation, Inc. (CRi; Woburn, MA). “Being able to analyze multiple markers in a single cell to understand the behavior of signaling pathways will significantly aid in disease diagnosis and therapy development.”

While the first big application for in-vivo optical molecular imaging was infectious disease, oncology has been an important next step according to Caliper Life Sciences’ (Hopkinton, MA) Stephen Oldfield PhD. Indeed, Carestream Health Molecular Imaging (Rochester, NY) reports a surge of interest from oncologists just in the past couple of years. William McLaughlin, Director of Research and Advanced Applications for Carestream, says that at the American Association for Cancer Research (AACR) annual meeting two years ago, he saw significantly more interest in analytical techniques such as gel documentation and western blotting–but in 2008 noticed that more people were asking about the newer technology. Then at this year’s AACR meeting (April 18-22, Denver, CO), the majority of leads were for in vivo imaging, he said.

“The products have reached a point where they provide a lot of benefit to researchers,” McLaughlin explained, noting that in the past year or so he’s seen a shift in percentages: Previously most of Carestream’s molecular imaging customers were hard core imaging people; now, more customers are in application areas.

State-of-the-art optical molecular imaging systems enable noninvasive visualization of biological processes in vivo, enabling researchers to watch disease progression over time in the same animal. They use multiple fluorochromes to selectively target biological processes, and visualize small groups of cells (usually 50 is sufficient for research needs, though Oldfield says Caliper has followed tumors composed of just five cells–to demonstrate the technology’s capability). They enable testing at intervals to illustrate how tumors develop and respond to drugs, and their output can be co-registered with images produced by other modalities such as computed tomography (CT) and magnetic resonance imaging (MRI) systems.

Moving up for drug discovery

For drug discovery, Oldfield says the technology has been used mainly at the end of the process, but is now being pushed much further upstream, to help determine which cell signaling pathways are affected by a drug. Previously the pathways were studied in vitro and millions of compounds were screened, he explains, but the newer approach lets researchers narrow down their work to perhaps 10 or 20 compounds, look at the pathways, learn what triggers this or that enzyme, and focus on compound optimization and drug efficacy. Oldfield says in vivo systems enable researchers to “fail faster” by getting the compounds into animals sooner so they can learn more quickly and accelerate the whole screening process. Observing disease progression in a live animal can provide all kinds of other information as well, he says.


(Courtesy Caliper Life Sciences)

Pharmaceutical companies don’t publish much (and are typically tight lipped about the technologies that help them get ahead), but Oldfield says he has just begun to see publications from the pharma labs demonstrating correlation between the upstream and downstream ends of the process.

In addition to this, in-vivo imaging is moving closer to clinical trials to enable testing of dosing levels. McLaughlin and Oldfield note that the approach has proven attractive for imaging of inflammation and for stem cell research. Explaining its use for imaging the inflammation that accompanies heart disease, McLaughlin explains that “vulnerable plaques have certain signatures of inflammation that indicate whether they are benign or active.” Oldfield points to observation of inflammation associated with asthma, arthritis, and stroke. A slideshow on Caliper’s website explains that all of the most commonly employed optical reporter labeling strategies have been used to generate light-producing stem cells; Oldfield explains that these can be seen tracking to the heart following cardiovascular damage.

The latest technology progress relates to 3D imaging for more precise pinpointing and quantification. Oldfield says Caliper has done much to improve software to enable this and make it easily accessible. And Carestream is working on a multimodal animal rotation system designed to eventually enable 3D visualization. The idea is to enable change of modalities (optical and x-ray) without moving the animal or focal plane–and register the imagery with precision. McLaughlin says the system will find the optimal angle for the optical signal and keep track of the rotation angle to enable tracking of changes over time.–Barbara G. Goode

Sourced and published by Henry Sapiecha 8th Oct 2009

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Plastic Solar Cells For Electronic Devices

Currently silicon-based solar cells are flooding the market. Industry pundits can foresee a hopeful future for low-cost, flexible solar cells. If we can make solar devices other than silicon based materials then they can be used for all sorts of applications beyond just the traditional solar panels on house rooftops. It will be great if we can have solar cells for portable electronic devices too.

Luping Yu, Professor in Chemistry, and Yongye Liang, a Ph.D. student, both at the University of Chicago, and five co-authors are working to develop a new semiconducting material called PTB1, which converts sunlight into electricity. The University accredited the patent rights to the technology to Solarmer last September. The license covers numerous polymers under development in Yu’s laboratory, confirmed by Matthew Martin. He is a project manager at University of ChicagoTech, the University’s Office of Technology and Intellectual Property. A patent is pending.

Solarmer Energy Inc. is spreading its wings in this direction. They are willing to incorporate technology invented at the University of Chicago. The commercial-grade prototype will be completed at the end of this year. It will be eight square inches with a lifetime of three years. This plastic solar device will have the efficiency of eight percent. This eight percent efficiency will give an edge to the Solarmer Energy Inc. over its competitors. Dina Lozofsky, vice president of IP development and strategic alliances at Solarmer states, “Everyone in the industry is in the 5 percent to 6 percent range.”

The active layer of PTB1 is around 100 nanometers in thickness, and the width is nearly 1,000 atoms. If we want to produce a small amount of the PTB1 material it will take considerable amount of time, and the whole procedure will be multi-step process. But, still the biggest advantage of this technology lies in its simplicity. Several products are being synthesized in other laboratories in the U.S., but the competitive advantage lies in the steps of production too. Other devices need far more extensive engineering work for commercial viability. “We think that our system has potential,” Yu said. “The best system so far reported is 6.5%, but that’s not a single device. That’s two devices.”

Sourced and published by Henry Sapiecha 1st July 2009

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