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131.
Jeong Gwi-Taek Park Don-Hee Hwang Baik Park Kyungmoon Kim Si-Wouk Woo Je-Chang 《Applied biochemistry and biotechnology》2002,98(1-9):1115-1127
The growth properties of Panax ginseng hairy roots transformed by Agrobacterium rhizogenes were compared between flask and aerated column or stirred bioreactor. In flask cultures, sucrose, initially 30 g/L, was nearly
exhausted after 45 d of culture. The pH of the medium dropped from 5.5 to 4.96 after 10 d, but afterward it gradually increased
to 6.4. After 45 d, hairy roots grew about 16-folds. The growth rate of hairy roots in air-bubble column or stirred bioreactor
cultures was 1.13 (1.11) to 1.23 (1.20) g fresh wt (dry wt)/(g of cells·d), respectively. For both bioreactors, growth was
about three times as high as in the flask cultivation. 相似文献
132.
Dorothy J. Park Tammy D. Fulmer Charles F. Beam 《Journal of heterocyclic chemistry》1981,18(3):649-651
C(α),O-Dilithiooximes were prepared in an excess of lithium diisopropylamide and condensed with several 2-aminobenzophenones, followed by acid hydrolysis of the oximes to the ketones, which then underwent cyclodehydration and linear dehydration to give substituted quinolines or dihydrobenz[c]acridines. 相似文献
133.
Tae Oan Ahn Jung Ho Kim Jong Chan Lee Han Mo Jeong Jong-Yoon Park 《Journal of polymer science. Part A, Polymer chemistry》1993,31(2):435-441
A macro-azoinitiator containing polyarylate segment and azo group was prepared by the solution polycondensation of azobiscyanopentanoyl chloride and hydroxy-terminated polyarylates having viscosity-average molecular weights of 6200, 8100, and 12 400. These macro-azoinitiators were used in the radical polymerization of styrene to synthesize polyarylate-polystyrene block copolymers. Thermal properties measured by the differential scanning calorimetry indicated the phase separated morphology of the block copolymers except at low molecular weight of the block constituents. © 1993 John Wiley & Sons, Inc. 相似文献
134.
Ovshinsky SR Young RT Allred DD DeMaggio G Van der Leeden GA 《Physical review letters》1987,58(24):2579-2581
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139.
Summary Real hypersurfaces of an almost Hermitian manifold naturally admit an almost contact metric structure and the (f, g, u, v, w, , , )-structure is defined on submanifolds of codimension 3 of an almost Hermitian manifold. We study the so-called semi-invariant submanifolds of a complex space form with almost contact metric compound structure which is a general notion of (f, g, u, v, w, , , )-structure.Dedicated to professor Eulyong Pak on his 60th birthdayThis research was partially supported by Korean Science and Engineering Foundation Grant. 相似文献
140.
Determination of sulfite in Oriental herbal medicines 总被引:4,自引:0,他引:4
Kim YK Koh E Park SY Chang SY Park SJ Na WI Kim HJ 《Journal of AOAC International》2000,83(5):1149-1154
Sulfite was detected in 7 varieties of Oriental herbal medicines (Pueraria radix, Zingiberis rhizoma, Platycodon radix, Adenophora radix, Pinellia tuber, Astragalus radix, and Paeonia radix) on the Korean market. Sulfiting of commercial Oriental herbal medicines by fumigation with burning bituminous coal was simulated, and the accumulation of sulfite was investigated by using fresh Platycodon radix roots obtained from a growing field. The sulfite level reached a plateau in 9 h, and the maximum sulfite level found by the Monier-Williams (MW) method (AOAC 990.28) was 1020 ppm. The sulfite content in the simulated Platycodon radix sample determined by alkali extraction followed by ion-exclusion chromatography with electrochemical detection (AOAC 990.31) was approximately 17% lower on average than the MW results. Free-sulfite levels determined by acid extraction and ion-exclusion chromatography with electrochemical detection were between 19 and 49% of the MW results. The advantages of different methods for sulfite determination and the significance of the results are discussed. 相似文献