The interest in nanoscale materials stems from the fact that new properties are acquired at this length scale and, equally important, that these properties * To whom correspondence should be addressed. Phone, 404-8940292; fax, 404-894-0294; e-mail, mostafa.el-sayed@ chemistry.gatech.edu. † Case Western Reserve UniversitysMillis 2258. ‡ Phone, 216-368-5918; fax, 216-368-3006; e-mail, burda@case.edu. § Georgia Institute of Technology. 1025 Chem. Rev. 2005, 105, 1025−1102

Chemistry and properties of nanocrystals of different shapes.

Polymer/layered silicate nanocomposites: a review from preparation to processing

http://staff.ulsu.ru/moliver/ref/polymers/pott11.pdf

Graphene-based polymer nanocomposites

Recently, polymer nanocomposites reinforced with lower volume fraction of nanoceramics and carbon nanotubes have attracted steadily growing interest due to their peculiar and fascinating properties as well as their unique applications in commercial sectors. The incorporation of nanoceramics such as layered silicate clays, calcium carbonate or silica nanoparticles arranged on the nanometer scale with a high aspect ratio and/or an extremely large surface area into polymers improves their mechanical performances significantly. The properties of nanocomposites depend greatly on the chemistry of polymer matrices, nature of nanofillers, and the way in which they are prepared. The uniform dispersion of nanofillers in the polymer matrices is a general prerequisite for achieving desired mechanical and physical characteristics. In this review article, current development on the processing, structure, and mechanical properties of polymer nanocomposites reinforced with respective layered silicates, ceramic nanoparticles and carbon nanotubes will be addressed. Particular attention is paid on the structure–property relationship of such novel high-performance polymer nanocomposites.

Structural and mechanical properties of polymer nanocomposites

Polypropylene/calcium carbonate nanocomposites

Polymer–clay nanocomposites: exfoliation of organophilic montmorillonite nanolayers in polystyrene

Acetaldehyde, acrolein, and formaldehyde are the principal toxic aldehydes present in cigarette smoke and contribute to the risk of cardiovascular disease and noncancerous pulmonary disease. The rapid growth of the use of electronic cigarettes (e-cigarettes) has raised concerns over emissions of these harmful aldehydes. This work determines emissions of these aldehydes in both free and bound (aldehyde–hemiacetal) forms and other carbonyls from the use of e-cigarettes. A novel silicon microreactor with a coating phase of 4-(2-aminooxyethyl)-morpholin-4-ium chloride (AMAH) was used to trap carbonyl compounds in the aerosols of e-cigarettes via oximation reactions. AMAH–aldehyde adducts were measured using gas chromatography–mass spectrometry. 1H nuclear magnetic resonance spectroscopy was used to analyze hemiacetals in the aerosols. These aldehydes were detected in the aerosols of all e-cigarettes. Newer-generation e-cigarette devices generated more aldehydes than the first-generation e-cigarettes because o...

http://pubs.acs.org/doi/pdf/10.1021/acsomega.6b00489

Aldehyde Detection in Electronic Cigarette Aerosols.

In this paper, we present a silicon carbide MEMS resonant strain sensor for harsh environment applications. The sensor is a balanced-mass double-ended tuning fork (BDETF) fabricated from 3C-SiC deposited on a silicon substrate. The SiC was etched in a plasma etch chamber using a silicon oxide mask, achieving a selectivity of 5:1 and etch rate of 2500 Aring/min. The device resonates at atmospheric pressure and operates from room temperature to above 300degC. The device was also subjected to 10 000 g shock (out-of-plane) without damage or shift in resonant frequency. The BDETF exhibits a strain sensitivity of 66 Hz/muepsiv and achieves a strain resolution of 0.11 muepsiv in a bandwidth from 10 to 20 kHz, comparable to state-of-the-art silicon sensors

A SiC MEMS Resonant Strain Sensor for Harsh Environment Applications

A non-invasive method of detecting or screening for lung cancer in a subject specimen is provided. The method includes detecting elevated levels of one or more carbonyl-containing volatile organic compounds (VOCs) that are biomarkers for lung cancer in exhaled breath from the subject specimen. The method may further include obtaining exhaled breath from the subject specimen; forming adducts of the carbonyl-containing VOCs with a reactive chemical compound; quantifying the adducts of the carbonyl-containing VOCs to establish a subject value for each of the adducts; and comparing each subject value to a threshold healthy specimen value for each of the adducts of the carbonyl-containing VOCs. One or more subject values at quantities greater than threshold healthy specimen values are also useful for screening for lung cancer in the subject specimen.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/cam4.162

Noninvasive detection of lung cancer using exhaled breath

The chemical and microstructural characteristics of silicon carbide films deposited on 100 mm diam, silicon (100) wafers in a large-volume, low-pressure chemical vapor deposition (LPCVD) furnace using dichlorosilane (SiH 2 Cl 2 ) and acetylene (C 2 H 2 ) were investigated. The deposition temperature was held constant at 900°C and the pressure ranged between 460 and 510 mTorr. X-ray photoelectron spectroscopy data indicated that stoichiometric SiC was deposited using SiH 2 Cl 2 -to-C 2 H 2 molar ratios of 4:1, 6:1, and 8:1. X-ray diffraction showed that the stoichiometric films were highly textured, 3C-SiC(111) at all locations across each wafer. These findings indicate that the SiH 2 Cl 2 /C 2 H 2 precursor system has great potential for use in large-scale LPCVD furnaces and produces SiC films with a microstructure that has advantageous properties for use in high-frequency resonator micromechanical devices.

Xiao-An Fu

Papers

Polymer–clay nanocomposites: exfoliation of organophilic montmorillonite nanolayers in polystyrene

Aldehyde Detection in Electronic Cigarette Aerosols.

A SiC MEMS Resonant Strain Sensor for Harsh Environment Applications

Noninvasive detection of lung cancer using exhaled breath

Deposition of Polycrystalline 3C-SiC Films on 100 mm Diameter Si(100) Wafers in a Large-Volume LPCVD Furnace