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951.
对农杆菌介导的烟草遗传转化条件进行探索,以20 mg/L的潮霉素作为转化苗的筛选压,稀释至OD600为O.2~O.3的农杆菌对外植体浸染15 min,于添加300 mg/L头孢霉素的生根培养基中诱导生根,可稳定获得较高的阳性转化率.经PCR和PCR-Souttlern检测,阳性转基因植株达84.8%以上.通过本研究建立了一种稳定高效的功能基因烟草遗传转化体系. 相似文献
952.
Soo Kyung Bae Min‐Jung Kim Eon‐Jeong Shim Doo‐Yeoun Cho Ji‐Hong Shon Kwang‐Hyeon Liu Eun‐Young Kim Jae‐Gook Shin 《Biomedical chromatography : BMC》2009,23(6):568-572
A simple and rapid HPLC method using fluorescence detection was developed for determination of irbesartan in human plasma. Sample preparation was accomplished through a simple deproteinization procedure with 0.4 mL of acetonitrile containing 800 ng/mL of losartan (internal standard), and to a 0.1 mL plasma sample. Chromatographic separation was performed on a Zorbax Xclipse XDB C18 column (150 × 4.6 mm, i.d., 5 µm) at 40°C. An isocratic mobile phase, acetonitrile:0.1% formic acid (37:63, v/v), was run at a flow‐rate of 1.0 mL/min, and the column eluent was monitored using a fluorescence detector set at excitation and emission wavelengths of 250 and 370 nm, respectively. The retention times of irbesartan and losartan were 4.4 and 5.9 min, respectively. This assay was linear over a concentration range of 10–5000 ng/mL with a lower limit of quantification of 10 ng/mL. The coefficient of variation for this assay precision was less than 8.48%, and the accuracy exceeded 94.4%. The mean relative recoveries of irbesartan and losartan were 98.4 and 99.1%, respectively. This method was successfully applied for pharmacokinetic study after oral administration of irbesartan (300 mg) to 23 Korean healthy male volunteers. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
953.
The large deformation of a cantilever beam under point load at the free tip is investigated by an analytic method, namely the homotopy analysis method (HAM). The explicit analytic formulas for the rotation angle at the free tip are given, which provide a convenient and straightforward approach to calculate the vertical and horizontal displacements of a cantilever beam with large deformation. These explicit formulas are valid for most practical problems, thus providing a useful reference for engineering applications. The corresponding Mathematica code is given in the Appendix. 相似文献
954.
Zhuoyu Ji Hongxiang Li Yaling Liu Wenping Hu 《Applied Physics A: Materials Science & Processing》2008,91(2):301-303
In this paper we propose a method for the integration of the synthesis of silver-tetracyanoquinodimethane (AgTCNQ) and the
fabrication of its devices within one step. The method was performed by electroplating Ag between gold coplanar micro-gap
electrodes in tetracyanoquinodimethane (TCNQ) solution. As soon as silver was electrochemically dissolved in the TCNQ solution,
it immediately reacted with TCNQ to form AgTCNQ and then deposited between Au gap electrodes. With the continuing of the reaction,
the Au micro-gap electrodes were connected by AgTCNQ to form Au/AgTCNQ/Au coplanar gap devices. With this electroplating technique,
series gap devices of AgTCNQ were fabricated, and the devices exhibited switching phenomena with good reproducibility. This
method integrated the synthesis of AgTCNQ and the fabrication of its devices within a single step, and should be also inspirable
for other charge transfer complexes.
PACS 81.05.Hd; 81.20.Ka; 82.45.Aa; 82.45.Qr 相似文献
955.
Spatial patterns of the uncatalyzed bromate – catechol – sulfuric acid system in a thin fluid layer were observed. A mixture of dots, strips and circles was formed by interaction of chemical reaction, diffusion and hydrodynamic instabilities. 相似文献
956.
Zhi‐guo Zhang Ji‐bing Yuan Huai‐jun Tang Hao Tang Li‐na Wang Ke‐Li Zhang 《Journal of polymer science. Part A, Polymer chemistry》2009,47(1):210-221
A novel nonconjugated copolymer (PVKEu) with carbazole segments and phenanthroline [Eu(β‐diketonate)3] moieties was synthesized via free radical copolymerization, and characterized by FTIR, 1H NMR spectroscopy, GPC, ICP, and elemental analysis. The copolymer exhibited good solubility, as well as good thermal stability and high glass transition temperature. The photoluminescence (PL) of this polymer in solution and in solid film has been studied. A multi‐layer device with the configuration of ITO/PEDOT: PSS (40 nm)/PVKEu (70 nm)/BCP (15 nm)/AlQ3 (30 nm)/LiF/Al exhibited nearly monochromatic red emission at 615 nm and voltage‐independent spectral stability. Our results suggest that enhancing the ligand‐mediated energy transfer between the matrix polymer and europium complex is a potential method to improve the electroluminescence performance of the Eu‐chelated polymers. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 210–221, 2009 相似文献
957.
958.
Li‐Ming Tang Ji‐Qian Wu Yi‐Qun Duan Li Pan Yan‐Guo Li Yue‐Sheng Li 《Journal of polymer science. Part A, Polymer chemistry》2008,46(6):2038-2048
Five novel vanadium(III) complexes [PhN = C(R2)CHC(R1)O]VCl2(THF)2 ( 4a : R1 = Ph, R2 = CF3; 4b : R1 = t‐Bu, R2 = CF3; 4c : R1 = CF3, R2 = CH3; 4d : R1 = Ph, R2 = CH3; 4e : R1 = Ph, R2 = H) have been synthesized and characterized. On activation with Et2AlCl, all the complexes, in the presence of ethyl trichloroacetate (ETA) as a promoter, are highly active precatalysts for ethylene polymerization, and produce high molecular weight and linear polymers. Catalyst activities more than 16.8 kg PE/mmolV h bar and weight‐average molecular weights higher than 173 kg/mol were observed under mild conditions. The copolymerizations of ethylene and norbornene or 1‐hexene with the precatalysts were also explored, which leads to high molecular weight copolymers with high comonomer incorporation. Catalyst activity, comonomer incorporation, and polymer molecular weight as well as polydispersity index can be controlled over a wide range by the variation of precatalyst structure and the reaction parameters such as Al/V molar ratio, comonomer feed concentration, and polymerization temperature. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2038–2048, 2008 相似文献
959.
Nai Yun Ji Xiao Ming Li Chuan Ming Cui Bin Gui Wang 《中国化学快报》2007,18(8):957-959
Two new brominated diterpenes,namely,laurendecumtriol and 11-deacetylpinnaterpene C,were isolated and identified from the marine red alga Laurencia decumbens.Their structures were established on the basis of various NMR spectroscopic techniques and HR-ESI-MS analyses. 相似文献
960.
Gang Liu Chunping Liu Lin Sun Rongjun Qu Hou Chen Chunnuan Ji 《Chemistry of Heterocyclic Compounds》2007,43(10):1290-1300
A series of N-substituted 4-amino-6,7,8-trimethoxyquinazoline derivatives has been synthesized from 4-chloro-6,7,8-trimethoxyquinazoline
and aryl (or benzyl) amines using 2-propanol as a solvent. The starting material 4-chloro-6,7,8-trimethoxyquinazoline has
been synthesized from natural gallic acid by a novel route. Their structures have been verified by elemental analysis and
IR, 1H, and 13C NMR spectroscopy. The title compounds have been evaluated for their in vitro antiproliferative activities against some cancer
cells by the MTT method. Unfortunately, most of the compounds tested have exhibited a weaker anticancer activity than the
reference standard drug PD153035.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, 1521–1531, September, 2007. 相似文献