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71.
Tian F Wang X Teng D Yang Y Guan Q Ao C Wang J 《Applied biochemistry and biotechnology》2011,165(5-6):1225-1234
A multiplex polymerase chain reaction (m-PCR) assay was developed for the simultaneous detection of multiple components of genetically modified (GM) soybean. It uses two sets of primers (I, lectin1/35S/CP4; II, lectin2/35S/CP4) specific for a soybean reference gene, the 35S promoter, and an event-specific gene. Amplified fragments of 118, 414, 195, and 320 bp were easily detected by agarose gel electrophoresis and were positively confirmed by sequencing. Primer set concentrations and annealing temperatures in the m-PCR were optimized. The optimized m-PCR conditions were obtained for primer set I at a ratio of 1:2:3 and a 59.2 °C annealing temperature and set II at the same ratio and 58.6 °C, 60.3 °C, and 61.2 °C annealing temperatures. The sensitivities of the two m-PCR primer sets (I and II) were 0.25% and 0.5%, respectively. The results showed that this m-PCR assay provides rapid, reliable, and effective identification of multiple components of GM soybean in feed. 相似文献
72.
73.
An effective one-pot synthesis of quinolines bearing diverse C3-piperazinyl functions was developed by using a modified Friedl?nder's protocol. The method not only enables the synthesis of our early reported c-Met inhibitor on a large scale, but also provides a way to generate novel multi-substituted quinolines for further structure-activity relationship (SAR) study. 相似文献
74.
In this paper, the problem of controller design for Lur’e systems guaranteeing dichotomy is investigated. On the basis of Kalman-Yakubovich-Popov (KYP) lemma and two frequency equalities, a new methodology for the dichotomy analysis of the Lur’e systems is proposed. A linear matrix inequality (LMI) based criterion is derived, which is equivalent to the Leonov’s frequency-domain one, while for the dichotomy analysis and synthesis which is more straightforward than the frequency-domain one. In virtue of this result, a dynamic output feedback controller ensuring the dichotomy property for Lur’e systems is designed. Finally a numerical example is included to demonstrate the validity and the applicability of the proposed approach. 相似文献
75.
The cyclization reactions of arylamines with 2-deoxy-D-ribose or glycals were reinvestigated in the current report. In the montmorillonite KSF- or InCl(3)-initiated reactions of 2-deoxy-D-ribose with arylamines, a pair of diastereomeric tetrahydro-2H-pyran-fused tetrahydroquinolines was obtained in a nearly 1:1 ratio where the structure of one diastereomer was incorrectly assigned in the literature. Meanwhile, the diastereoselectivity in InBr(3)-catalyzed cyclization of glycals with arylamines was also incorrectly reported previously. It was found that high diastereomeric selectivity was achieved only when a C5-substituted glycal was used; otherwise, a pair of diastereomers was obtained in moderate yield with 1:1 diastereomeric ratio. Furthermore, tetrahydrofuran-fused tetrahydroquinolines 5b and 5b' were also prepared successfully by using TBDPS-protected ribose as the glycal precursor and montmorillonite KSF as the activator. 相似文献
76.
77.
Mathematische Zeitschrift - We show that if the base frequency is Diophantine, then the Lyapunov exponent of a $$C^{k}$$ quasi-periodic $$SL(2,{\mathbb {R}})$$ cocycle is... 相似文献
78.
文章以一个风险厌恶销售商与风险中性供应商所组成的两级供应链为背景,以条件风险价值(CVaR)和期望利润的加权平均作为销售商的决策目标,对期权契约下销售商的订购策略及供应链协调问题进行了研究,并对比分析了销售商以CVaR为目标时的情形。在给出销售商在不同风险厌恶程度下的最优订购策略后,文章进一步给出了供应链相应的协调条件,并分析了此时期权权利金,销售商的风险厌恶程度和期望利润权重等参数对供销双方收益的影响,发现“利润-CVaR”法下销售商的风险厌恶程度对供销双方利润的影响与CVaR法下的情况有所不同,但权利金依然起到了分配整体供应链利润的作用,且销售商期望利润权重的增加会降低自身收益水平而提高供应商利润。最后,文章通过数值模拟的方式对上述结论进行了验证。 相似文献
79.
Z. Y. Tan S. L. Sun X. F. Xu C. Zhou Y. H. Ao H. X. Zhang 《Journal of Polymer Science.Polymer Physics》2005,43(19):2715-2724
Polycarbonate (PC) was blended with acrylic impact modifiers (AIMs). The effects of modifiers weight fraction on the Izod impact strength and yield strength of PC/AIM blends were investigated. The samples with 4% modifiers were aged under the Tg of PC in an air‐circulating oven, and the effects of aging time on impact strength, yield strength, modulus, elongation at break, post yield stress drop (PYSD) values, and morphology of fracture surface were investigated. The effects of aging time on the shape of stress–strain curve were also investigated. The aged samples were heat‐treated over the Tg of PC to erase the effects of physical aging. It was found that the drop of impact strength caused by physical aging can be recovered, the increment of yield strength and PYSD value caused by physical aging can only be partly recovered, and the heat‐treatment over the Tg of PC caused further increment of modulus. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2715–2724, 2005 相似文献
80.
§ 1. Introduction LetΩ R3beasmoothboundedopenset,f(t,x ,v)bethedistributionfunctionofcar riersattimet >0 ,positionvectorx∈Ωandvelocityvectorv∈R3.Theforcefieldactingonthecarriersisdenotedbythe3 dimensionalvectorfunctionE(t,x) ,thepotentialcorespondingtoE(t,x)isdenotedbyu(t,x) ,then (f,E)satisfythefollowingBoltzmann Poissonsystem tf +v· xf +E· vf =Q(f) , (t,x ,v)∈R+ ×Ω×R3,(1 .1 )E =- xu ,-Δxu =ρ , (t,x) ∈R+ ×Ω ,(1 .2 )whereρ(t,x) =∫R3 f(t,x ,v)dvisthecarriernum… 相似文献