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981.
本研究利用阴离子型芘衍生物8-羟基芘-1,3,6-三磺酸三钠盐(HPTS),建立了一种快速、可视化的对硝基苯胺(PNA)荧光检测方法.检测原理主要是基于PNA通过非共价作用而导致的HPTS的荧光淬灭.通过测量加入PNA后HPTS在512 nm处荧光强度的变化,可以实现PNA的荧光检测.本方法的线性范围为10~120μmol/L,检出限(3σ/s)为4.6μmol/L.对本方法的抗干扰性以及方法的实际应用性进行了考察.结果表明,本方法具有低成本、高灵敏度、高选择性、操作简便等优点. 相似文献
982.
Yanhui Chen Ganji Zhong Benjamin S. Hsiao Zhongming Li 《Journal of Polymer Science.Polymer Physics》2013,51(22):1618-1631
The structure evolution of the oriented layer (skin) and unoriented layer (core) from injection‐molded isotactic polypropylene samples upon uniaxial drawing is probed by in situ synchrotron X‐ray scattering. The X‐ray data analysis approach, called “halo method”, is used to semiquantitatively identify the transformation process of crystal phase upon uniaxial drawing. The results verify the validation of the stress‐induced crystal fragmentation and recrystallization process in the deformation of the injection‐molded samples under different temperatures. Furthermore, the end of strain softening region in the engineering stress‐strain curves explicitly corresponds to the transition point from the stress‐induced crystal fragmentation to recrystallization process. Basically, the skin and core layers of the injection‐molded parts share the similar deformation mechanism as aforementioned. The stretching temperature which dramatically affects the relative strength between the entanglement‐induced tie chains and the adjacent crystalline lamellae determines the crystal structural evolution upon drawing. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1618–1631 相似文献
983.
Zhi‐Yong Xiao Xia‐Chang Wang Gui‐Ping Zhang Zhong‐Liang Huang Li‐Hong Hu 《Helvetica chimica acta》2010,93(4):803-810
Five new terpenoids, including four eudesmane‐type sesquiterpenoids, 1 – 4 , and one labdane‐type diterpenoid, 6 , together with ten known compounds, were isolated from the roots of Chloranthus spicatus. The structures and their relative configurations were mainly established by 1D‐ and 2D‐NMR spectra, and MS experiments. 相似文献
984.
Bo Ding Wei‐Wei Ma Yi Dai Hao Gao Yang Yu Ye Tao Yi Zhong Xin‐Sheng Yao 《Helvetica chimica acta》2010,93(12):2488-2494
Two new iridoids, 10‐O‐benzoyl‐6′‐O‐α‐L ‐arabino(1→6)‐β‐D ‐glucopyranosylgeniposidic acid ( 1 ), deacetyl‐6‐ethoxyasperulosidic acid methyl ester ( 2 ), along with 14 other known iridoids, were isolated from the whole plant of Hedyotis diffusa Willd. Their structures were determined on the basis of spectroscopic analysis. The short‐term‐memory‐enhancement activities of compounds 1, 7 – 9, 11 , and 13 were evaluated on an Aβ transgenic drosophila model. 相似文献
985.
986.
Chang‐Shuai He Lu‐Fang Liu Lei Guo Jian‐Zhong Wu 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(3):289-292
Both 10‐(2‐hydroxyethyl)acridin‐9(10H)‐one, C15H13NO2, and 10‐(2‐chloroethyl)acridin‐9(10H)‐one, C15H12ClNO, have monoclinic (P21/c) symmetry and supramolecular three‐dimensional networks. But the differences in the intermolecular interactions displayed by the hydroxy group and the chlorine substituent lead to stronger intermolecular π‐stacking interactions and hydrogen bonding, and hence a significantly higher melting point for the former. 相似文献
987.
988.
Z. Zhong D. Chapman D. Connor A. Dilmanian N. Gmur M. Hasnah 《Synchrotron Radiation News》2013,26(6):27-34
The APS hosted a two-day workshop on Catalysis Research at the APS on September 12-13, 2005. The goal of the workshop was to evaluate current catalysis-related research at the APS and to plan future directions. The outcome of the meeting will be a report with recommendations to promote new, and support current, catalysis research at the APS. The workshop was attended by 82 participants representing industry, national laboratories, and universities. 相似文献
989.
Dr. Chun‐Yi Sun Prof. Xin‐Long Wang Chao Qin Jun‐Ling Jin Zhong‐Min Su Peng Huang Kui‐Zhan Shao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(11):3639-3645
Two anionic metal–organic frameworks (MOFs) with 1D mesoporous tubes ( 1 ) and chiral mesoporous cages ( 2 ) have been rationally constructed by means of a predesigned size‐extended hexatopic ligand, namely, 5,5′,5′′‐(1,3,5‐triazine‐2,4,6‐triyl)tris‐ (azanediyl)triisophthalate (TATAT). Charge neutrality is achieved by protonated dimethylamine cations. Notably, the two MOFs can be used to separate large molecules based on ionic selectivity rather than the size‐exclusion effect so far reported in the literature. Owing to the imino triazine backbone and carboxyl groups of the hexatopic ligand, which provide important host–guest interactions, rare solvatochromic phenomena of 1 and 2 are observed on incorporating acetone and ethanol guests. Furthermore, guest‐dependent luminescence properties of compound 2 were investigated, and the results show that luminescence intensity is significantly enhanced in toluene and benzene, while quenching effects are observed in acetone and ethanol. Thus, compound 2 may be a potential material for luminescent probes. 相似文献
990.
Baojun Bian Min Dai Lishang Jiang Qing Zhang Yifei Zhong 《Journal of Optimization Theory and Applications》2011,151(2):402-417
This paper is concerned with liquidation of an illiquid stock. The stock price follows a fluid model which is dictated by the rates of selling and buying over time. The objective is to maximize the expected overall return. The method of constrained viscosity solution is used to characterize the dynamics governing the optimal reward function and the associated boundary conditions. Numerical examples are given to illustrate the results. 相似文献