Ultrasonic treatment regulates the properties of gelatin emulsion to obtain high-quality gelatin film.

Gelatin emulsion was an important process for preparing gelatin films. A gelatin film with water resistance and ductility could be prepared using gelatin emulsion, whereas the prepared gelatin film has several defects (e.g., low tensile strength and poor thermal stability). This study aimed to modify gelatin emulsion through ultrasonic treatment, then gelatin film was prepared by the modified gelatin emulsion. The results showed that: under the condition of ultrasonic treatment for 12 min at 400 w, zeta potential and viscosity of gelatin emulsion were the largest; thickness, water vapor permeability (WVP) and water solubility (WS) of corresponding gelatin film were the lowest, and the tensile strength (TS), elongation at break (EAB), denaturation temperature (Tm) and enthalpy value (ΔH) of corresponding gelatin film were the highest. The above result suggested that ultrasonic treatment can be used to prepare a gelatin film with better quality by regulating the properties of gelatin emulsion, and a certain correlation was found between the properties of gelatin emulsion and the properties of gelatin film.

Thermopower and specific heat of the organic molecular salt (TMTSF)(2)ClO(4): observation of the narrow band response.

Measurements of thermopower S(a)(T) along the highly conducting a axis and specific heat of the Bechgaard salts (TMTSF)(2)ClO(4) for various cooling rates through the anion ordering temperature T(a) = 24 K were carried out. Sign reversal in S(a)(T) is found below T(a) and it decreases with increasing cooling rate, which is attributed to the change of a narrow band filling level as the temperature and the cooling rates change. The crossover from 2D to 3D in S(a)(T) is observed around 15 K. The onset temperature of anion ordering in S(a)(T) decreases from 29.8 to 24.2 K as the cooling rate increases. Meanwhile, the electronic specific heat coefficient γ has a pronounced change within this temperature region, giving strong evidence for a narrow band contribution. The difference in the specific heat between the quenched and relaxed states follows a T-cubic law from 5 to 24 K, implying a lattice distortion by the ordered anion only. The entropy estimated from the specific heat peak between 28 and 15 K is Rln (4/3) lower than the value Rln2, consistent with the thermopower result that some anions have been ordered far above T(a) for the relaxed state.