This paper reports a new method of titration for very weak acids andbases using the appearance of incisions on oscillopolarogram to indicate theend-point.This method has the advantages of rapidity,simplicity,no indica...This paper reports a new method of titration for very weak acids andbases using the appearance of incisions on oscillopolarogram to indicate theend-point.This method has the advantages of rapidity,simplicity,no indicatorneeded as well as good precision.展开更多
The structures of Nylon-1010 with different draw ratios have been investigated by using Small-AngleX-ray Scattering(SAXS).It is shown that by using a simple geometrical construction the following structureparameters c...The structures of Nylon-1010 with different draw ratios have been investigated by using Small-AngleX-ray Scattering(SAXS).It is shown that by using a simple geometrical construction the following structureparameters can be directly derived from the correlation function,the long period(L),the thickness of thecrystal amorphous interphase(dtr),the lamellar thickness(do),the“invariant”(Q),the specific inner surface(Os),and the electron density difference between the core of the crystallites and the amorphous matrix(η_ε-η_ω)。展开更多
The 2E spectra and substituent effects and target gas pressure dependence of the 2E spectra of 7 biphenyl derivatives were discussed. The electron-donating groups favour the molecular ions, but the electron withdrawin...The 2E spectra and substituent effects and target gas pressure dependence of the 2E spectra of 7 biphenyl derivatives were discussed. The electron-donating groups favour the molecular ions, but the electron withdrawing groups favour the fragaent ions produced by losing the substituents from molecular ions. The variation of target gas pressure affects the TIC,sample ion current,and the ratio of sample ion current to TIC sharply.However it has no effect on the fragmentation pattern.展开更多
文摘This paper reports a new method of titration for very weak acids andbases using the appearance of incisions on oscillopolarogram to indicate theend-point.This method has the advantages of rapidity,simplicity,no indicatorneeded as well as good precision.
文摘The structures of Nylon-1010 with different draw ratios have been investigated by using Small-AngleX-ray Scattering(SAXS).It is shown that by using a simple geometrical construction the following structureparameters can be directly derived from the correlation function,the long period(L),the thickness of thecrystal amorphous interphase(dtr),the lamellar thickness(do),the“invariant”(Q),the specific inner surface(Os),and the electron density difference between the core of the crystallites and the amorphous matrix(η_ε-η_ω)。
文摘The 2E spectra and substituent effects and target gas pressure dependence of the 2E spectra of 7 biphenyl derivatives were discussed. The electron-donating groups favour the molecular ions, but the electron withdrawing groups favour the fragaent ions produced by losing the substituents from molecular ions. The variation of target gas pressure affects the TIC,sample ion current,and the ratio of sample ion current to TIC sharply.However it has no effect on the fragmentation pattern.
