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of material interest

Speaker gives crystal clear sound new meaning ClearView Audio, Waltham, Mass., created a new glass speaker named Clio that boasts an “invisible” design consisting of an ultra-thin, curved acrylic glass transducer, which outputs sound in multiple direc- tions. Clio’s patented Edge Motion audio systems use a differentiating mechanical principal to generate sound—instead of pushing from be- hind, like traditional cone speakers, Edge Motion-driven speakers actu- ate a thin membrane along the side in a manner that creates an extremely efficient, piston-like motion in front. The speaker uses a sin- gle piece of curved acrylic glass that sits on a dock, which vibrates it in a finely tuned way so that it can play music. Clio uses a 2-in. woofer and piezoelectric actuators in its base, which stimulate two thin membranes Clio, a new “invisible” speaker, is available in (one per channel) running along both sides of its transparent curved silver, bronze, or charcoal hues. transducer, producing 360° stereo sound emitted from both the front and rear faces of the 1-mm-thick acrylic material. clearviewaudio.com.

Fire-resistant paper handles the heat Researchers from the Shanghai Institute of Ceramics, Chinese Academy of Sciences, developed a new paper that is resistant to fire and high temperatures (>450°C). It is made from a calcium phosphate compound, hydroxyapatite (HAp), Ca10(PO4)6(OH)2, and can potentially be used for both printing and writing. Chemi- cally, the main component of the conventional paper is cellulose, a natural polymer ex- tracted from the pulp of wood or grass. Other minor components, such as bleaching agents and additives, are also part of the mix. To have the characteristics necessary for high-performance printing, the paper must be coated with a very thin layer of inor- ganic material. Printing on HAp paper (top). “HAp is a calcium phosphate with high biocompatibility and essentially no tox- The material is fire resistant icity. It is white in color, abundant in nature, nonflammable, and high-temperature (bottom). Courtesy of resistant. Therefore, it is an ideal candidate for fabricating paper. However, the most Ying-Jie Zhu. challenging problem is its low flexibility. To overcome this, we adopted HAp ultra- long nanowires as the paper-making material,” explains Professor Ying-Jie Zhu. http://english.sic.cas.cn.

Ancient Chinese pottery contains rare form of iron oxide New analysis of ancient Jian wares reveals the distinctive pottery con- tains an unexpected and highly unusual form of iron oxide. This rare com- pound, called epsilon-phase iron oxide, was only recently discovered and characterized by scientists and so far has been extremely difficult to create with modern techniques. “What is amazing is that the ‘perfect synthesis con- ditions’ for epsilon-phase iron oxide were encountered 1000 years ago by Chinese potters,” says Catherine Dejoie, scientist at University of Berkeley Laboratory’s Advanced Light Source, Calif. Jian wares, such as tea bowls, are famous for their shiny black glaze and variable brown and silvery surface patterns known as “oil spot” and “hare’s fur.” The ceramic bowls, produced by the thousands in giant , were made during the in the Province of Southeast Modern replica of a tea bowl between 960 and 1279 AD. Analysis reveals that hare’s fur patterns (top) with “oil spot” surface patterns contain small quantities of epsilon-phase iron oxide mixed with hematite, produced by Prof. Weidong Li, while oil spot patterns boast large quantities of highly pure epsilon-phase Shanghai Institute of Ceramics. Close-up of the oil spot pattern from iron oxide, an unexpected finding. Marked by extremely persistent mag- an ancient Jian ware provided by the netization, epsilon-phase iron oxide could hold the key to better, cheaper Museum of Fujian Province. permanent magnets used in data storage and other electronics. lbl.gov.

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