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MAO Mingfei LUO Jianguang REN Li CHEN Zhequan LIU Zhifang College of Materials South China University of Technology Guangzhou China Department of Chemical Engineering Nanhua University Hengyang China 《Chinese Journal of Reactive Polymers》2002,(1)
1. INTRODUCTION Poly (diphenyl oxide) (DPO) resins are a series of heat-resisting thermosetting resins. In 1960s, the West House Company applied them to make H class insulting materials and got an extensive use successfully [1]. But due to the three main… 相似文献
3.
CuO/γ-Al2O3 catalysts were prepared by plasma treatment and conventional impregnation methods. The catalytic combustion of two kinds of volatile organic compounds (VOCs), toluene and benzene, were carried out over these CuO/γ-Al2O3 catalysts. The surface properties of these catalysts were characterized by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The experimental results showed that in catalytic combustion the activity of the CuO/γ-Al2O3 catalyst prepared via plasma was much higher than that of the CuO/γ-Al2O3 catalyst prepared by conventional impregnation method. XRD results showed that an enhanced dispersion had been achieved with the plasma treatment. SEM results indicated that the size became much smaller and the surface became more uniform with the plasma treatment. 相似文献
4.
Chao Luo Qianxiong Zhou Wanhua Lei Jianguang Wang Baowen Zhang 《Supramolecular chemistry》2013,25(9):657-662
A new unsymmetrical aniline-based squaraine (SQ2) bearing binding unit of Hg2+ ion was designed and synthesised. SQ2 can form 1:2 inclusion complex with β-cyclodextrin, and the resulting complex, which undergoes absorption and fluorescence bleaching upon binding Hg2+, can serve as a turn-on colorimetric or fluorescent chemosensor in organic solvent-free aqueous solution for thiol-containing amino acids with high selectivity and tunable measuring range. 相似文献
5.
Two new furostanol glycosides, torvosides O (1) and P (2), were isolated from leaves of Solanum torvum. Their structures were completely and unambiguously assigned by one‐ and two‐dimensional NMR techniques (1H NMR, 13C NMR, TOCSY, HSQC, ROESY and HMBC), ESI‐MS spectrometry and chemical methods. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
6.
Tao Zhang Hongliang Fan Jianguang Zhou Qinhan Jin 《Journal of polymer science. Part A, Polymer chemistry》2009,47(12):3056-3065
This article reports the synthesis, optical properties, and pH responses of a water‐soluble poly(phenylene ethynylene) with pendant carboxylate groups. This conjugated polyelectrolyte, PPE‐OBS, was prepared via a facile synthetic route, using 1,4‐di(ethyl 4‐oxy‐butyrate)‐2,5‐diiodo‐benzene as polymeric monomer and followed by the alkali induced saponification. PPE‐OBS absorbs strongly in the blue region and emits a moderately intense fluorescence. However, it subjects to unstable emission in neutral aqueous media, which is believed to arise because the polymer tends to become more hydrophobic via protonation and to form much heavier aggregates (clusters). Subsequent studies on the interaction and stabilization of PPE‐OBS with various surfactants indicate that its fluorescence stability can be largely improved in the presence of a small amount of surfactant. More interestingly, even at low pH, the surfactant‐stabilized polyelectrolyte with its pendant groups being ? COOH rather than ? COO? remains water‐soluble and emits efficiently, which is expected of great significance for the covalent linkage to bio‐molecules. In addition, the sensitive pH response in emission spectrum of PPE‐OBS/surfactant complex over a relatively wide range suggests surely a potential access to the fluorescent sensing of pH variation. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3056–3065, 2009 相似文献
7.
A novel separation technique of complexation high-speed counter-current chromatography (HSCCC) using copper ion as a complexation agent was first developed to isolate 5-hydroxyisoflavone isomers from Belamcanda chinensis (L.) DC. According to the partition coefficient and separation factor, the two-phase solvent system composed of light petroleum-ethyl acetate-methanol-water (3:5:3:5, v/v) and copper nitrate (0.10mol/L in the lower phase) was selected. 9.2mg isoirigenin (1), 46.4mg irigenin (2) and 1.2mg 5,7,4'-trihydroxy-6,3',5'-trimethoxyisoflavone (3) were simultaneously purified from 100mg crude extract by HSCCC with the purity of 95.06%, 96.98% and 93.69%, respectively. As evidenced by the results of UV-Vis spectroscopy, the stoichiometries of the copper ion with the three 5-hydroxyisoflavones were all 1:1 and their chelating power was 3>2>1. Those explained the complexation HSCCC behavior. It is the first report that includes the practical application of complexation HSCCC and explanation of its chromatographic behavior. 相似文献
8.
对实验动物肿瘤进行活体31P MRS研究首要的是有效地固定动物.本文初步研究了用噻胺酮麻醉后的小鼠S180肿瘤在麻醉过程中31P MRS随时间的变异性.研究发现噻胺酮是一个安全系数高、起效快、麻醉过程适宜且对肿瘤的31P MRS无显著影响的麻醉药.因而噻胺酮适用于连续测定31P MRS的需要. 相似文献
9.
为了测量超高速碰撞过程中产生的闪光现象,进而研究相近碰撞速度、不同入射角度(弹道与靶板平面的夹角)条件下超高速碰撞产生闪光在整个物理过程的闪光强度随时间的变化规律,设计了适用于瞬态闪光测量的光学高温计测量系统。通过二级轻气炮加载LY12球形铝弹丸,运用设计的瞬态高温计测量系统分别进行了入射角度为30°,45°,60°和90°相近碰撞速度条件下碰撞LY12铝靶产生闪光现象的测量。获得了平均碰撞闪光强度峰值与碰撞角度的关系,平均碰撞闪光强度峰值随碰撞角度的减小而增大,碰撞角度为30°时表现更为明显。 相似文献
10.
XiaoLiang Dong Deren Han Zhifeng Dai Lixiang Li Jianguang Zhu 《Journal of Optimization Theory and Applications》2018,179(3):944-961
An accelerated three-term conjugate gradient method is proposed, in which the search direction can satisfy the sufficient descent condition as well as extended Dai–Liao conjugacy condition. Different from the existent methods, a dynamical compensation strategy in our proposed method is considered, that is Li–Fushikuma-type quasi-Newton equation is satisfied as much as possible, otherwise, to some extent, the singular values of iteration matrix of search directions will adaptively clustered, which substantially benefits acceleration the convergence or reduction in the condition number of iteration matrix. Global convergence is established under mild conditions for general objective functions. We also report some numerical results to show its efficiency. 相似文献