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Herein, the assessment of commercial beef and chicken bouillons in terms of heterocyclic aromatic amines (HAAs) and some of their precursors was evaluated. Creatine and creatinine levels were ranged between 0.57–0.80 and 0.28–0.94 mg g−1, respectively. Glutamic acid was found to be the most abundant amino acid in both bouillons. 2-amino-3,7,8-trimethylimidazo[4,5-ƒ]quinoxaline (7,8-DiMeIQx, up to 0.03 ng g−1) was the only quantified analyte in beef bouillons, whereas it (up to 0.08 ng g−1) was determined in addition to 2-amino-3-methylimidazo[4,5-ƒ]quinoxaline (IQx, up to 0.08 ng g−1) in chicken bouillons. Creatine, creatinine and free amino acid composition did not have the capacity to initiate the formation of HAAs. Therefore, bouillons do not pose risk in terms of HAAs. However, it should be noted that multiple factors, such as the substrate amount and production conditions, may affect the results. Glutamic acid content is remarkable in commercial bouillons sold in Turkey. 相似文献
5.
Ik Rae Jeong Jeong Ok Kwon Dong Hoon Lee 《Communications Letters, IEEE》2007,11(5):432-433
To provide authentication to the Diffie-Hellman key exchange, a few integrated key exchange schemes which provide authentication using the DSA signature have been proposed in the literature. In this letter we point out that all of the previous Diffie-Hellman-DSA schemes do not provide security against session state reveal attacks. We also suggest a strong Diffie-Hellman-DSA scheme providing security against session state reveal attacks as well as forward secrecy and key independence 相似文献
6.
Fatih Porikli 《Journal of Real-Time Image Processing》2006,1(1):33-40
In this survey, we present a brief analysis of single camera object detection and tracking methods. We also give a comparison of their computational complexities. These methods are designed to accurately perform under difficult conditions such as erratic motion, drastic illumination change, and noise contamination. 相似文献
7.
Woo Yong Sung Seung Min Lee Wal Jun Kim Jong Girl Ok Ho Young Lee Yong Hyup Kim 《Diamond and Related Materials》2008,17(6):1003-1007
Complementary electroplating combined with electrophoresis enhanced the field emission characteristics of emitters by improving the adhesions between CNT emitters and substrate. The emitting current of the CNT emitters prepared by our combined method increased nine times higher than that of CNT emitters prepared by electrophoresis only, since electroplating improved the adhesion of CNT emitters. During the life-time measurement for 10 h, the emitting current of CNT emitters fabricated by electrophoresis only was drastically decreased to 13% of the initial current, while that prepared by the combination of electrophoresis and successive electroplating decreased to 64% of the initial current. We suggest that our method is a promising approach for the efficient fabrication of reliable CNT emitters. 相似文献
8.
O Ok Park 《Korean Journal of Chemical Engineering》1986,3(2):153-163
Molecular model approach has been used to predict the dispersion characteristics of flexible polymer chains in confined geometries.
The analysis ranges from the early stage dispersion to the steady Taylor dispersion of the simple linear dumbbell model polymer
chains. For the early stasje dispersion the ray method was applied; an Aris type moments rnothod was useful for the Taylor
dispersion. Two parallel plates were chosen as a confining geometry and the specific initial condition of a point source in
the midway of the gap was chosen for simplicity. It was found that the qualitative difference in dispersion properties of
deformable polymer chains starts from the early stage compared with those of single Brownian particles. And it turns out that
one parameter, which is similar to the relative spacing of the dumbbell to the gap of confining geometries, is useful to see
the dispersion characteristics of the dumbbells. 相似文献
9.
The esterification of the hydroxyl group of starch with DuPont Surlyn was considered as pretreatment method of starch before blending with polyolefins. In treating starch with Surlyn, two different raction conditions were taken to optimize reaction conditions. First, the esterification reaction was carried out in 110°C xylene with oleic acid as a catalyst. Second, the reaction out in a 90°C mixture of deionized water and xylene with ceric ammonium nitrate(CAN) as an initiator. Starch granules would be swollen above the gelatinization temperature in water. In both cases starch was midified by Surlyn to have good compatibility with low-density polyethylene (LDPE). The mechanical and theological properties were examined for blends of the treated starch and LDPE. This system may be one of the biodegradable polymer blends that sufficiently retain properties as a packaging film. 相似文献
10.
The reactive compatibilization of syndiotactic polystyrene (sPS)/oxazoline‐styrene copolymer (RPS)/maleic anhydride grafted ethylene‐propylene copolymer (EPR‐MA) blends is investigated in this study. First, the miscibility of sPS/RPS blends is examined by thermal analysis. The cold crystallization peak (Tcc) moved toward higher temperature with increased PRS, and, concerning enthalpy relaxation behaviors, only a single enthalpy relation peak was found in all aged samples. These results indicate that the sPS/RPS blend is miscible along the various compositions and RPS can be used in the reactive compatibilization of sPS/RPS/EPR‐MA blends. The reactive compatibilized sPS/RPS/EPR‐MA blends showed finer morphology than sPS/EPR‐MA physical blends and higher storage modulus (G') and complex viscosity (η*) when RPS contents were increased. Moreover, the impact strength of sPS/RPS/EPR‐MA increased significantly compared to sPS/EPR‐MA blend, and SEM micrographs after impact testing show that the sPS/RPS/EPR‐MA blend has better adhesion between the sPS matrix and the dispersed EPR‐MA phase. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2084–2091, 2002 相似文献