On-site simultaneous quantification of multiple contaminants in a water body is challenging, especially for parameters requiring complicated chemical reactions to measure such as Chemical Oxygen Demand (COD), ammonia nitrogen, and phosphate. A novel disposable multiplexed microfluidic device has been developed herein that allows the quantitative detection of up to five parameters at once. Solid reagent rather than commonly used liquid reagent was used to ensure long shelf life, and a "flow to dissolve" mechanism was provided accordingly for the thorough dissolution and mixing of a solid reagent on chip. Samples from river water and industrial wastewater were tested using the microfluidic chip, showing less than 15% deviation from results acquired with the traditional standard method. The test time though was only 1/6 of that required by the traditional method. In addition, the feasibility of using a smartphone to collect the colorimetric signal was discussed, and a data analysis method was provided for quantification purposes. The combination of the multiplexed chip and smartphone imaging provides a convenient and practical way to obtain accurate information on the water quality within a short period of time without the use of any sophisticated instruments.
The simulation of wood crib fire behavior in a confined space with fire dynamics simulator (FDS) was presented in this paper, including the heat release rate, flame temperature, central temperature of crib, and oxygen concentration. In the simulation, the cone calorimeter data, such as ignition temperature and heat release rate of wood material measured from cone calorimeter test, were inputted into FDS. Simulations were compared with the results of practical wood crib burning experiments. The simulation results shown that the inputted heat release rate data from cone calorimeter tests obtained with different external heat flux (35-50 kW m -2 ) had little influence on the simulation results. The heat release rates were in good agreement with the experimental measurement with the biggest difference of 13.9 % in peak value. FDS underestimated the flame temperatures at lower positions about 10 % during the steady state, and the difference between simulation and experiment in flame temperature decreased as the height of measurement position increased. Although there was a big difference in decay phrase, the temperatures in the middle of wood crib were successfully simulated for the overlapped curves during (I) Fast growth stage and (II) Moderate growth stage of burning. The oxygen concentrations were overestimated because the oxygen concentrations measured at the height of 1.8 m in the space were higher than the experimental data with an average difference of 15.5 %. On the whole, an effective way was provided with reasonable results to study the burning characteristics of wood crib fire with numerical simulation.
Surface enhanced Raman spectra (SERS) has emerged as a promising tool for the rapid and ultrasensitive recognition of trace amount of environmental pollutants. Hierarchical SERS substrate usually shows superior performance...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.