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Mechanical Engineering. 2006;128(09):30-33. doi:10.1115/1.2006-SEP-1.
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This paper assesses the risk posed by nanotech products in endangering human health. Material characteristics that have little bearing on health effects in bulk materials, such as surface area, may become important when trying to measure the hazard from trace amounts of nanomaterials. Nanotoxicologists may have to use a separate and unique set of metrics for determining what the safe exposure to various nanomaterials. The precision control that engineers have in making nanoscale materials may also amplify their effect. Naturally occurring nanoscale materials, such as particles formed in combustion exhaust, are formed over a wide range of sizes. Any given particle size will make up only a small part of the overall sample, diluting the potential ill effects. Nanoengineered materials come in a tight range of sizes. Research that helps lay out the basic parameters of the problem-figuring out which characteristics of nanoscale particles are most important.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2006;128(09):34-37. doi:10.1115/1.2006-SEP-2.
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This paper highlights various aspects in the development of nanoscale armors for soldiers. Founded at the Massachusetts Institute of Technology in 2002, Institute for Soldier Nanotechnologies (ISN) is dedicated to achieving such objectives through nanotechnology. Paula T. Hammond, an associate professor of chemical engineering at the institute, leads a research team that hopes to discover materials that can both detect and resist chemical weapons or biological attacks. The difficulty in using multiple polymers—and other materials—has long been that polymers tend to separate from each other. Hammond's solution is a novel use of polyelectrolytes. Eventually, molecules in a soldier's uniform will be able to neutralize specific chemicals and literally pop the cells of less-than-friendly biological agents. Hammond plans to also include a layer of nano-size molecules called dendrimers, which can react with mustard gas and deactivate it. Many of the coatings they have come up with have the added benefit of being waterproof-protecting soldiers from the elements as well as from things like E. coli.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2006;128(09):38-40. doi:10.1115/1.2006-SEP-3.
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This paper describes the pros and cons of computer-aided design (CAD). CAD packages lack features to easily make the intuitive, complex shapes so pervasive in modern products. It is much easier with CAD to create a part with square features and rectangles and straight lines and round things. Even in a current design project, engineers will sculpt the design in clay, scan it with a digitizer, bring it back into the CAD package, then change it into a solid model and refine that. One of the biggest criticisms of CAD systems is that digital design is slower than sketching and that inhibits the brainstorming process. Today’s systems are not equipped to let engineers play with a design. Engineers start with a basic design and they can change parameters as they draw, but cannot change complete concepts midstream or cut and paste ideas between designs. Most CAD packages include features that track design changes so engineers working collaboratively can see what's been changed, where, when, and why.

Commentary by Dr. Valentin Fuster

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