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A new method to determine titanium dioxide in cement by Microwave Digestion-DAPM VIS Spectrophotometry which has many advantages such as simple operation, safe and fast, dissolve completely is presented in this paper. The determination conditions and working parameters of the microwave digestion instrument including the species and dosage of digestion reagent, wavelength, reaction time and the dosage of DAPM were optimized. The results show that samples were dissolved by HNO3-HF-H2O2, 395nm as the wavelength and 12mL of DAPM. The method has been validated by determination of titanium dioxide in national standard reference materials of GBW03201, GBW03201c, GBW03207 and GBW03205. The results were in agreement with certified values and the RSD was 1.07%-4.52%. The recovery ratio was ranging from 91.8% to 108.0% and the ｜△lgC｜was less than 0.018. Comparison with the traditional digestion method that analytical cement samples of Sichuan, there is no significant difference between the two methods by Student's t test. This new method provide a new way for quick and accurate to determine the content of titanium dioxide in cement.

This paper took the objective of preparing high-performance, low-cost biological adsorbent for printing and dyeing wastewater, and the adsorption experiment of dyestuff wastewater with high chromaticity and high biodegradability was studied. The Methylene Blue was adsorbed by the prepared Humulus Japonicus Leaves (HJ), the effects of adsorption time, pH, dosage of adsorbent, initial Methylene Blue concentration and temperature on the adsorption process were investigated, and the adsorption mechanism was described by adsorption isotherm, adsorption thermodynamics and adsorption kinetics, and the results showed that: when HJ was added 0.15g and ph was 7, the temperature was 30°C (303K), adsorption was carried out for 20min, simulated dye wastewater, adsorption efficiency of Methylene Blue of 100mg/l were excellent, adsorption rate reached up to 92%, the equilibrium adsorption rate was positively correlated with the initial concentration of CV dye. Humulus leaves adsorption CV Gibbs free energy of ΔG0, ΔS>0 showed spontaneous adsorption process, the adsorption process Methylene Blu was more suitable for the Freundlich isothermal adsorption equation, the adsorption kinetics accorded with the quasi two level kinetic model, the adsorption of the Methylene Blue dye molecule by the HJ was chemically adsorbed as the rate control step, the Methylene Blue molecule was mainly adsorbed on the surface of the Humulus leaves; the model of internal diffusion kinetics showed that there was membrane diffusion and internal diffusion of the HJ in the process of Methylene Blue adsorption. The experimental results showed that HJ as adsorbent can effectively remove Methylene Blue from dye wastewater, and the research results provide a new method and idea for biological treatment of dye wastewater.