A shake-flask method was employed to determine the water solubility (-lgS (w)) and n-octanol/water partition coefficient (lgK (ow)) of 20 substituted phenols at 298.15 K. And optimized calculation was carried out at B3LYP/6-311G** level with DFT method. Afterwards the obtained parameters were taken as theoretical descriptors to establish the QSPR models for predicting -lgS (w) and lgK (ow), in which the conventional correlation coefficients (R (2)) are 0.9800 and 0.9941, respectively. The two models were further validated by variance inflation factors (VIF) and t-test. Upon comparison, the stability and predictive power are more advantageous than those based on AM1 molecular orbital method and molecular connectivity method.
As a special functional and structural material, the rare metal beryllium has been widely applied in many key areas due to its excellent nuclear properties, optical properties and physical properties such as low density, high specific stiffness, high specific strength, and excellent thermal properties. This article systematically reviews application of beryllium in strategic nuclear energy, high-energy physics, inertial navigation systems, aircraft structural components, optical systems and commercial fields. The paper also examines how beryllium promoted technological advances and improved the facilities performance in its applications fields. Beryllium plays an important role in the development of nuclear technology, defense, and aerospace, which make beryllium become a strategic and critical engineering material. The paper provides a reference for scientists and technicians to employ beryllium in more fields.
Surface modification of poly(vinylidene fluoride) (PVDF) membrane was accomplished by the adsorption of ferric hydroxide sol to impove its hydrophilicity. The adsorption curves of the membranes were analyzed by weight measurements, and the typical results showed a two-platform character in low concentration. The effects of the adsorption time, the ferric hydroxide sol concentration, the test temperature, as well as the water cleaning time on the adsorption amount were observed. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR/ FTIR) analysis showed that the adsorption of ferric hydroxide sol on poly(vinylidene fluoride) microporous membranes (PVDFMM) is effective. The membranes hydrophilic performance was represented by water contact angle measurements. The water contact angles changes from the virgin 128°to the lowest value 81.90° in the range of 0~0.10 mol/L ferric hydroxide aqueous solution. The results indicated that ferric hydroxide sol can be immobilized on the PVDF films by adsorption, and the membrane hydrophilic performence increases with the increase of the adsorption amount of the ferric hydroxide sol onto the PVDF membrane surface.
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