The diffusion coefficient is an important parameter in the field of migration and diffusion. Different diffusion theories have been established to estimate the diffusion coefficient, including the weight gain rate. However, the research was based on the migration of different solvents into simple polymers. Few reports focused on the migration of components from propellant and liner into ethylene‐propylene terpolymer (EPDM) insulation. In this paper, a new parameter named surface area diffusion rate was proposed to measure the migration of components from propellant and liner at interfaces of EPDM insulation, and the comparison with the traditional weight gain rate was made. The result shows that the surface area diffusion rate is independent of the shape of the material and is more reliable than previously used methods. Furthermore, the relationship of the surface area diffusion rate with time and temperature was investigated. In addition, the diffusion activation energy and the relationship of surface area diffusion rate with the bonding properties were discussed.
Sampled with the pigments extracted from Chinese chestnut shell by alkali solution, chromaticity with protein and starch and chromaticness and red index are related to. The characteristics were compared with that of the standard caramel pigment. Methods were used by spectrometer and colorimeter. Compared with caramel pigments, better chromaticity and stability with starch and protein, lower chromacticness and higher red index of pigments in shell were shown.
The objective of this research was to study the treatment effect of micro-polluted water usingconventional activated carbon filter(CACF) andaeration activated carbon filter(AACF), test the effect of backwashing on the performance of carbon filters, and provide a reference for water plant upgrading. The removal efficiency of pollutants and the impact of backwash of AACF was studied and compared with CACF. The results showed that, with an influent turbidity of 0.67 versus 0.44NTU, CODMnof 2.48 versus 2.74mg / L, UV254of 0.045versus 0.045cm-1and NH4+-N of 0.15 versus 0.11mg / L, the removal effect of turbidity, CODMn, UV254,and NH4+-N are 36.19% versus 33.67%, 30.63% versus 21.53%, 23.06% versus 26.57% and 34.34% versus 19.62% . AACF improved the treatment of CODMn,and NH4+-N by 26.66% and 60%. Backwash is found to enhance the performance of AACF on CODMnwith the removal efficiency increases from the 25.82% to 29.75% after 2 hr backwash, and stabilizes at approximately 30% at the consequent 6 hrs; Backwash decreases UV254removal from 17.51% to 16.64% after 2 hr backwash, increases it to 19.64% to after 4 hr treatment, and drops to 13.44% after 8 hrs. Additionally, backwash has no significant effect on NH4+-N.
With the continuing phenomenon of eutrophication, the pollution of nitrogen has caused wide concern. Lack of organic carbon sources is always considered to be a key problem for nitrogen removal efficiency and cost when conventional biological nitrogen removal process was used to the treatment of ammonium-rich wastewater, but the anaerobic ammonium oxidation(ANAMMOX)can solve this problem .Anammox has so many advantages that it has good prospects in the biological nitrogen removal in wastewater. Anammox bacteria grows slowly, has a long generation time, and is susceptible to the environmental conditions. DO, Temperature, pH and organic can impact the process of anammox, so it is necessary to take careful methods to cultivate Anammox biomass. Depending on the purpose of improve water quality, appropriate treatment reactors and seed sludge should be selected to start ANAMMON process. The discovery of anaerobic ammonia oxidation, the reaction mechanism, influence application, the enrichment of anammox bacteria, physiological and biochemical characteristics of anammox bacteria, the start of anaerobic ammonia oxidation are reviewed in this paper.
Secondary water supply equipment was designed based on the current water supply source and municipal pipe network. The combination between Water purification and pressure-superposed water supply could guarantee the drinking water security, fully exploit the municipal pipe network pressure, and effectively save the energy. Catalytic oxidation of ozone, complex adsorption, and microbial degradation collaborated to treat the micro-polluted water. Activated alumina was employed for the high fluoride water purification with HCl/NaOH deep regeneration. For the brackish water, membrane treatment was adopted. A collaborative technology of ozone oxidation, contact oxidation, and biological oxidation was used for the iron/manganese-rich water. The results showed that all the effluents could meet the requirement of "Sanitary standard for drinking water" (GB5749-2006) and "Water quality standards for fine drinking water" (CJ94-2005).
A new method was established for detecting a series of photoinitiators (PIs) in printed cartonboard food-packaging materials, which were benzophenone (BP), 4-methylbenzophenone (MBP), 1-hydroxycyclohexyl phenyl ketone (Irgacure184), ethyl-4-dimethylaminobenzoate (EDAB), 2-ethylhexyl-4-dimethylaminobenzoate (EHDAB) and 2-isopropylthioxanthone (ITX) by gas chromatography–mass spectrometry (GC/MS). Extraction was carried out with ethyl acetate by ultrasonic solvent extraction. Samples were analyzed by GC/MS in selected ion monitoring (SIM) mode. The results indicated that six kinds of PIs had good linear relations (R2>0.9989) in the range of 10~200 μg/L. Limit of Detections (LODs) and Limit of Quantifications ( LOQs ) of all kinds of PIs were 0.3~2.6 μg /kg and 1~8 μg/kg, respectively. The recoveries of six kinds of PIs at three kinds of concentrations researched (0.30 μg/kg, 0.60 μg/ kg, 1.0 μg/kg) were ranging from 66.7%~89.4%, with the Relative Standard Deviation (RSD) of 4.2%~10.6% (n=6). The results also suggested that PIs were detected in food packaging materials.
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