To investigate the nonlinear properties of wind waves, experiments are carried out in a wind-wave flume with slope bottom at different wind speeds and fetches. Both the internal structure and apparent features of the ...To investigate the nonlinear properties of wind waves, experiments are carried out in a wind-wave flume with slope bottom at different wind speeds and fetches. Both the internal structure and apparent features of the nonlin-earity of wind waves are studied by using bispectral and statistical analysis of surface elevations. The relations between bispectra and nonlinear apparent characteristics of wind waves are established and confirmed.展开更多
The reaction kinetics between diazide（4,4＇-biphenyl dibenzyl azide） and different diynes（dipropargyl bisphenol A and 1,3-diethynylbenzene） were studied by means of differential scanning calorimetry（DSC） and nuc...The reaction kinetics between diazide（4,4＇-biphenyl dibenzyl azide） and different diynes（dipropargyl bisphenol A and 1,3-diethynylbenzene） were studied by means of differential scanning calorimetry（DSC） and nuclear magnetic resonance spectroscopy（~1H-NMR）.DSC was adopted to analyze the reactions under bulk polymerization condition,while ~1H-NMR for solution reaction polymerization was conducted.The apparent activation energies（E_α） calculated by Kissinger＇s method were 77.96,81.24 k J/mol,which were confirmed by Friedman＇s method,and 65.45,69.36 k J/mol by ~1H-NMR for dispropargyl bisphenol A/4,4＇-biphenyl dibenzyl azide and 1,3-diethynylbenzene/4,4＇-biphenyl dibenzyl azide,respectively.The polymerizations between the diazide and diynes were first-order reactions based on calculation from both DSC and ~1H-NMR.The results showed that the reaction between dipropargyl bisphenol A and 4,4＇-biphenyl dibenzyl azide was easier than that between 1,3-diethynylbenzene and 4,4＇-biphenyl dibenzyl azide,verifying that the reactivity of aliphatic alkyne was higher than that of aromatic alkyne.展开更多
基金This study was supported in part by the National Natural Science Fundation of China
文摘To investigate the nonlinear properties of wind waves, experiments are carried out in a wind-wave flume with slope bottom at different wind speeds and fetches. Both the internal structure and apparent features of the nonlin-earity of wind waves are studied by using bispectral and statistical analysis of surface elevations. The relations between bispectra and nonlinear apparent characteristics of wind waves are established and confirmed.
基金Funded by the Financial Support of Shanghai Leading Academic Discipline Project(No.B502)Fundamental Research for the Central University
文摘The reaction kinetics between diazide（4,4＇-biphenyl dibenzyl azide） and different diynes（dipropargyl bisphenol A and 1,3-diethynylbenzene） were studied by means of differential scanning calorimetry（DSC） and nuclear magnetic resonance spectroscopy（~1H-NMR）.DSC was adopted to analyze the reactions under bulk polymerization condition,while ~1H-NMR for solution reaction polymerization was conducted.The apparent activation energies（E_α） calculated by Kissinger＇s method were 77.96,81.24 k J/mol,which were confirmed by Friedman＇s method,and 65.45,69.36 k J/mol by ~1H-NMR for dispropargyl bisphenol A/4,4＇-biphenyl dibenzyl azide and 1,3-diethynylbenzene/4,4＇-biphenyl dibenzyl azide,respectively.The polymerizations between the diazide and diynes were first-order reactions based on calculation from both DSC and ~1H-NMR.The results showed that the reaction between dipropargyl bisphenol A and 4,4＇-biphenyl dibenzyl azide was easier than that between 1,3-diethynylbenzene and 4,4＇-biphenyl dibenzyl azide,verifying that the reactivity of aliphatic alkyne was higher than that of aromatic alkyne.
