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991.
Yong Sam Chung Sun Ha Kim Gwang Min Sun Jong Myoung Lim Jong Hwa Moon Kye Hong Lee Young Jin Kim Jong Il Choi Ju Woon Lee 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(1):223-229
The analysis of mineral contents in space foods is needed to obtain an information on a comprehensive elemental composition
as well as the investigation on the effects of human nutrition and health based on the dietary intake of mineral elements.
Recently, six items of new Korean space foods (KSFs) such as kimchi, bibimbap, bulgogi, a ramen, a mulberry beverage and a
fruit punch which was developed by the KAERI, and the contents of more than 15 elements in the samples were examined by using
instrumental neutron activation analysis (INAA). Five biological certified reference materials, NIST SRM were used for analytical
quality control. The results were compared with those of common Korean foods reported, and these results will be applied toward
the identification of irradiated foods. 相似文献
992.
993.
Sungeun ParkSoohyun Bae Hyunho KimSeongtak Kim Young Do KimHyomin Park Soomin KimSung Ju Tark Chang-Sik SonDonghwan Kim 《Current Applied Physics》2012,12(1):17-22
High efficiency solar cells require good back surface field passivation and high back reflectance in the rear Al region. In module processes, wafer-based solar cell can break through stress during soldering uneven rear aluminum surfaces - a serious problem that affects throughput. This work examined rear surfaces with respect to controllable process factors such as ramping and cooling rates during rapid thermal processing, and the fineness of aluminum powder used in the screen-printed paste. A faster ramp up rate resulted in a uniform temperature gradient between the aluminum and silicon surfaces. As a results, the bumps on the aluminum surface were small and of high density. Fine aluminum metal powder in the paste for screen-printing contact points resulted in large distribution, high density bumps. Bumps formed during cooling in metallization, their sizes and densities were dependent the on uniformity of the aluminum and silicon liquid wetting of the silicon surface. 相似文献
994.
In order to investigate the calculation methods on crack resistance capacity of connection composed of cross shaped steel encased ultra high strength concrete (CSSEUHSC) columns and steel encased concrete (SEC) beams under cycle loads, six interior connection specimens were tested in the laboratory. A discussion on the crack resistance capacity was presented. Calculation methods of crack resistance capacity were deduced based on the experimental case and calculation results were in good agreement with the experimental results. The research results indicated that parameters of connection composed of CSSEUHSC columns and SEC beams with better crack resistance performance may be referred for engineering application. 相似文献
995.
Ag3PW12O40 and Ag4SiW12O40 showed high activity and stability in the synthesis of diethylene glycol ethyl ether with diethylene glycol and ethanol, on which the conversion is 80.2% and 78.4%, respectively, and the selectivity of diethylene glycol ether is 75.4% and 80.6%, respectively. After the third reaction cycle, Ag3PW12O40 and Ag4SiW12O40) still showed higher activity and selectivity, on which the conversion is 72. 6% and 77.5% respectively. But the activity of Ag3PMo12O40 is lower, the conversion is only 21.0%. IR, XRD, TG and n‐butylamine titrimetry showed that the catalysis may be connected with two kinds of acidic centers owned by heteropoly acidic salt. 相似文献
996.
We present a simple but effective method for small-angle measurement based on optical feedback interferometry (or laser self-mixing interferometry). The absolute zero angle can be defined at the biggest fringe amplitude point, so this method can also achieve absolute angle measurement. In order to verify the method, we construct an angle measurement system. The Fourier-transform method is used to analysis the interference signal. Rotation angles are experimentally measured with a resolution of 10^-6 rad and a measurement range of approximately from -0.0007 to +0.0007 rad. 相似文献
997.
The relationships between the morphological characteristics and the vulnerability of atherosclerotic plaque were analyzed
theoretically and several suggestions were proposed to evaluate the plaque vulnerability. Validated by animal experiments
and clinical studies, the theoretical results were confirmed.
Supported by the National Natural Science Foundation of China (Grant Nos. 10302016 and 60402023), the National Basic Research
Program of China (973 Program)(Grant No. 2006CB503803), and the National Hi-Tech Research and Development Program of China
(863 Program) (Grant No. 2007AA02Z448) 相似文献
998.
A silver oxide hydrosol has been prepared by reacting silver nitrate with sodium hydroxide in an aqueous solution. The colloidal particle composition and particle size have been characterized by X-ray diffractometry and transmittance electron microscopy. We have demonstrated that the sol is surface-enhanced Raman scattering active. One major advantage of this sol is the absence of the spectral interference arising from reaction products of the sol formation process. The mechanism of surface-enhanced Raman scattering activity is essentially contributed by the silver particles generated from the photochemical process during the laser excitation. 相似文献
999.
The degradation of neomycin B was reexamined, and a novel protocol was established to prepare the properly masked neomycin CD ring as a glycol donor in excellent yield. Glycosylation of the CD ring with glycol acceptors provided a facile access to versatile intermediates that could be utilized to synthesize a variety of novel neomycin B mimetics for RNA recognition. [reaction: see text] 相似文献
1000.
Reactions of aldehydes with 2 equiv of alkyne in the presence of TiX(4) (X = Cl, Br) regioselectively generated 1,5-dihalo-1,4-dienes in moderate to good yields with high (E,Z)-stereoselectivity. [reaction: see text] 相似文献