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991.
992.
Preface     
Song Gao 《Polyhedron》2011,30(18):2959
  相似文献   
993.
Three model drugs with different function groups were chosen to dialyze with dextran-graft-poly(N-isopropylacrylamide).Only ibuprofen could induce the formation of drug loaded micelles,which was confirmed with dynamic light scattering and transmission electron microscope.Hydrogen-bonding between the amide groups of poly(N-isopropylacrylamide) and the carboxyl groups of ibuprofen was driving force for the drug-loaded micelle.It was also found that the diameter of the ibuprofen-loaded micelles changed reversibly against temperature.  相似文献   
994.
Nanocomposites of poly (vinyl alcohol) with ethylamine modified zirconium phosphate (ZrP-EA) were prepared by solution blending. Their morphologies were elucidated with X-ray diffraction and transmission electron microscopy, while the thermal stability and flammability performance were characterized by thermogravimetric analysis, Fourier transform infrared spectra and microscale combustion calorimetry. It was established that the morphology of the nanocomposites evolved as ZrP-EA content increased. In the nanocomposites, catalytic degradation of the acetate groups remaining in poly (vinyl alcohol) occurred and catalytic carbonization was observed. Microscale combustion calorimetry revealed that the flammability performance of poly (vinyl alcohol) was improved by the introduction of zirconium phosphate nanoplatelets.  相似文献   
995.
In this paper, by using the cone theory and monotone iterative technique, we investigate the existence of extremal solutions and unique solution of the integral boundary value problem for a class of first-order impulsive integro-differential equations in a real Banach space. An explicit iterative scheme for the unique solution and an error estimate of the approximation sequence are also derived.  相似文献   
996.
This note studies the iterative solutions to the coupled Sylvester-transpose matrix equation with a unique solution. By using the hierarchical identification principle, an iterative algorithm is presented for solving this class of coupled matrix equations. It is proved that the iterative solution consistently converges to the exact solution for any initial values. Meanwhile, sufficient conditions are derived to guarantee that the iterative solutions given by the proposed algorithm converge to the exact solution for any initial matrices. Finally, a numerical example is given to illustrate the efficiency of the proposed approach.  相似文献   
997.
998.
The combination of atom transfer radical polymerization (ATRP) and click chemistry has created unprecedented opportunities for controlled syntheses of functional polymers. ATRP of azido‐bearing methacrylate monomers (e.g., 2‐(2‐(2‐azidoethyoxy)ethoxy)ethyl methacrylate, AzTEGMA), however, proceeded with poor control at commonly adopted temperature of 50 °C, resulting in significant side reactions. By lowering reaction temperature and monomer concentrations, well‐defined pAzTEGMA with significantly reduced polydispersity were prepared within a reasonable timeframe. Upon subsequent functionalization of the side chains of pAzTEGMA via Cu(I)‐catalyzed azide‐alkyne cycloaddition (CuAAC) click chemistry, functional polymers with number‐average molecular weights (Mn) up to 22 kDa with narrow polydispersity (PDI < 1.30) were obtained. Applying the optimized polymerization condition, we also grafted pAzTEGMA brushes from Ti6Al4 substrates by surface‐initiated ATRP (SI‐ATRP), and effectively functionalized the azide‐terminated side chains with hydrophobic and hydrophilic alkynes by CuAAC. The well‐controlled ATRP of azido‐bearing methacrylates and subsequent facile high‐density functionalization of the side chains of the polymethacrylates via CuAAC offers a useful tool for engineering functional polymers or surfaces for diverse applications. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1268–1277  相似文献   
999.
L&#;  LinHui  Ye  YanLin  Jiang  DongXing  Hua  Hui  Zheng  Tao  Li  ZhiHuan  Ge  YuCheng  Li  XiangQing  Lou  JianLing  Cao  ZhongXin  Song  YuShou  Xiao  Jun  Li  QiTe  Qiao  Rui  You  HaiBo  Chen  RuiJiu  Xu  HuShan  Wang  JianSong  Guo  ZhongYan  Zhang  XueYing  Li  Chen  Hu  ZhengGuo  Chen  RuoFu  Wang  Meng  Xu  ZhiGuo  Yue  Ke  Tang  Bin  Zang  YongDong  Zhang  XueHeng  Yao  XiangWu  Chen  JinDa  Bai  Zhen 《中国科学:物理学 力学 天文学(英文版)》2011,54(1):136-140

Knockout reaction experiment was carried out by using the 6He beams at 61.2 MeV/u impinging on a CH2 target. The α core fragments at forward angles were detected in coincidence with the recoiled protons at larger angles. From this exclusive measurement the valence nucleon knockout mechanism and the core knockout mechanism can be distinguished by the relation between the polar angles of the core fragments and the recoiled protons, respectively. It is demonstrated that the core knockout mechanism may result in some strong contamination to the real invariant mass spectrum.

  相似文献   
1000.
A series of imidacloprid derivatives containing an azopyridine motif as a photoswitchable functional group were designed and synthesized. The new version of photoresponsive imidacloprid analogues showed improved solubility in comparison with their azobenzene analogues. 1.2 to 2-fold activity difference was observed for these azopyridine-imidacloprids against house fly (Musca domestica) and cowpea aphid (Aphis craccivora) upon irradiation.  相似文献   
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