Films of BC(x)N(y) were produced in a plasma-enhanced chemical vapor deposition process using trimethylborazine as precursor and with H2, He, N2, and NH3, respectively, as auxiliary gas. These films deposited on Si(100) wafers or fused quartz glass substrates were characterized chemically by X-ray photoelectron spectroscopy and by synchrotron radiation-based total-reflection X-ray fluorescence combined with near-edge X-ray absorption fine structure. Independent of the auxiliary gas, the B-N bonds are dominating. Furthermore, B-C and N-C bonds were identified. Oxygen, present in the bulk (in contrast to the surface layer of some nanometers, where molecular oxygen and/or water are absorbed) as an impurity, is bonded to boron or to carbon, respectively. The relation of boron and nitrogen changes with the character of the auxiliary gas: cB/cN approximately = 4:3 (for H2 and He) and cB/cN approximately = 1 (for N2 or NH3). Furthermore, physical properties such as the refractive index and the optical band-gap energy were determined.
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http://dx.doi.org/10.1007/s00216-009-3056-6 | DOI Listing |
The Glycyrrhizae Radix et Rhizoma products processed with different methods, including raw materials(S) and products processed with honey according to the method in the Chinese Pharmacopoeia(Z) and Jianchangbang method(M), were analyzed in terms of the odor profile and volatile components by the electronic nose and headspace-gas chromatography-mass spectrometry(HS-GC-MS). The differential components in the three products were screened by chemometrics, on the basis of which the relative odor activity value(ROAV) was adopted to elucidate the odor differences among different products and the material basis of their odors. The results showed that the electronic nose effectively distinguished the products of Glycyrrhizae Radix et Rhizoma processed with different methods.
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In order to disintegrate nuclear fuel rods in the grid connection structure, a 10 kW fiber laser was used to cut a stainless steel simulation component with four layers of 3 mm thick plates and 12 mm gaps. The slit width is regarded as an important indicator to evaluate the cutting quality of the four-layer stainless steel plate. The results showed that good laser cutting quality can be successfully achieved under the proper process parameters.
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