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Catalysts of aluminum dihydrogen tripolyphosphate supported by activated carbon ((ATP-AC) were prepared by using activated carbon oxidized by Na2S2O8, H2O2 and HNO3, respectively, and characterized...

Potassium zinc phosphate was synthesized by solid-state reaction using K3PO4·3H2O and ZnSO4·7H2O as reagents. To investigate the influence of molar ratio, grinding time, holding temperature, holding time on yield and zinc content of the product, experimental project was designed by uniform design and data mining technology. Obtained product was characterized by X-ray diffraction, scanning electron microscope and energy disperses spectroscopy. The results show that the two mathematical models can be established by regression analysis according to yield and zinc content, which can be used to obtain the best technology conditions of solid-state reaction. Under the optimum reaction conditions: molar ratio of K3PO4·3H2O: ZnSO4·7H2O = 1.01, grinding time 31min, holding temperature 750°C, holding time 3.2 h, the prepared product is KZnPO4 with nano-lamellar structure, and the reaction average yield value is 84.33% and zinc content is 31.29%.

Flower-like ammonium cadmium phosphate monohydrate was synthesized by solid-state reaction at low temperature and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope, and elemental analysis. The product NH4CdPO4·H2O was obtained with flower-like morphology by the addition of fatty alcohol-polyoxyethylene ether surface-active agent. Based on Hess’s law, thermochemical cycle was designed to determine the dissolution enthalpies of reactants and products using a solution-reaction isoperibol calorimeter at 298.15 K, and the molar reaction enthalpy was calculated on the basis of above dissolution enthalpies. With the aid of other auxiliary thermodynamic data, the standard molar formation enthalpy of the title compounds was concluded: $$ \Updelta_{\text{f}} H_{\text{m}}^{-\!\!\!\!\circ} [{\text{NH}}_{4} {\text{CdPO}}_{4} \cdot {\text{H}}_{2} {\text{O}}] = ( - 1749.82 \pm 0.76)\; {\text{kJ}}\; {\text{mol}}^{ - 1} . $$

KZnPO 4 was synthesized by solid-state reaction at low temperature and characterized by X-Ray Diffraction, Scanning electron microscope and elemental analysis. Thermochemical study was performed with an isoperibol solution calorimeter. Based on Hess's law, thermochemical cycles were designed to determine the dissolution enthalpies of reactants and products using a solution-reaction isoperibol calorimeter at 298.15 K, and the molar reaction enthalpies were calculated on the basis of above dissolution enthalpies. The results show that the obtained product is layered shape KZnPO 4 . The standard molar formation enthalpy of the KZnPO 4 at 298.15 K is obtained.

In order to obtain the extraction dynamics of mogroside from grosvenori momordica by ultrasonic wave strengthening, two dynamics model were used to evaluate this process and the extraction efficiency. The results show that the ultrasonic wave strengthening can improve the extraction efficiency of mogroside in the experimental conditions. The ultrasonic wave strengthening extraction dynamics equation agrees with the dynamic equation In C = γ In t + λ. Under the high frequency of ultrasound extraction or high temperature or long extraction time, the extraction process will not be controlled by the dynamic. In order to achieve the medicinal compositions with high activity and stability, the frequency, temperature and duration of ultrasonic extraction should be controlled in a certain range.