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991.
The authors studied the content of volatile N-nitrosamines (NA) in the most common sausage products. It was established that the total content of NA in sausage products is not high and ranges from trace amounts up to 10 micrograms/kg product. The allowable doses of nitrite in the sausage manufacture being low, no relationship was discovered between the content of NA and residual nitrite in meat products. 相似文献
992.
993.
New methods for determining the “correlation length” for thickness fluctuations of a thin insulator film from data obtained in measurements of the electrical characteristics of MIS tunnel structures, i.e., without the use of microscopy, have been suggested and tested. One of these methods relies on statistical processing of electric current data for a random sample of structures. The other technique analyzes abrupt downward changes in current, observed in tests of devices under a sufficiently high bias. The methods have been tested on Al/SiO2/Si tunnel structures. The resulting estimates of the characteristic scale of thickness fluctuations are compared with the data obtained in direct measurements of this scale for the same oxide layers. 相似文献
994.
995.
L. L. Rokhlin T. V. Dobatkina N. R. Bochvar E. V. Lysova I. E. Tarytina 《Russian Metallurgy (Metally)》2007,(4):335-339
The effect of small chromium and yttrium additions (0.14–1.0 wt%) on the recrystallization of Al-Sc alloys having 0.1–0.4% Sc is studied with polarized light. The microstructure of cold-rolled samples annealed at 100–630°C for 1 h is examined. The chromium and yttrium additions are found to slightly affect the recrystallization temperature of the Al-Sc alloys: they increase or decrease it slightly depending on the scandium content. 相似文献
996.
An innovative technology for industrial wastewater treatment has been developed. The main focus of the new system is a transformation of persistent organic compounds (biorecalcitrant COD) into a biodegradable fraction, followed by high efficient biological elimination using specialised bacteria's. To fulfill these targets the Aqua-Biomant process integrates two treatment steps: an aerated biological upflow filter and a electrochemical oxidation technique using boron doped-diamond electrodes. The advantages of the process are high efficient COD removal with reduced energy consumption combined with low total residence time. 相似文献
997.
998.
999.
The conditions for synthesis of porous biocomposite materials based on calcium phosphate for fabricating implants with prescribed
pore-structure parameters, and the desired level of physical, chemical, and biological properties for clinical applications
are determined. The role of a bimodal pore structure in the substrate materials for cell cultures is shown.
__________
Translated from Steklo i Keramika, No. 4, pp. 23–26, April, 2007. 相似文献
1000.