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In this work, corn straw (CS) based porous carbon was prepared by one-step phosphoric acid (H 3 PO 4) low temperature activation. The impregnation ratios (H 3 PO 4 /CS, g/g) played an important role in the pore development. ACS 300-1 engineered at 300 °C and the impregnation ratio of 1.0 showed the maximal specific surface area of 463.89 m2/g with total pore volume of 0.387 cm3/g, attaining a high tetracycline (TC) uptake of 227.3 mg/g. The adsorption of TC onto ACS 300-1 was found tolerant with wide pH (2.0–10.0) and high ionic strength (0 – 0.5 M). The adsorption data can be fitted well by the pseudo-second order kinetic model and Langmuir isotherm model. The endothermic and spontaneous properties of the adsorption system was implied by Thermodynamic study. The findings of the current work conclude that one-step H 3 PO 4 activation is a green and promising method for corn straw based porous carbon that may be found with great potentials in antibiotic containing wastewater treatment. Image 1 • Corn straw based porous carbon (ACS 300-1) was facilely prepared by one-step phosphoric acid low temperature activation. • ACS 300-1 showed high microporosity and specific surface area with excellent TC uptake capacity of 227.3 mg/g. • ACS 300-1 was tolerant with wide pH (2.0–10.0) and high ionic strength (0–0.5 M). • The adsorption behavior of TC onto ACS 300-1 surface was both physisorption and chemisorption. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to develop a novel structural damping approach to reduce the sound pressure at a target point inside an enclosed cavity. In this approach, particle dampers filled with either metal or nonmetal particles are used. The dissipation mechanisms of such dampers are primarily related to the friction and collision of particle-wall and particle-particle contacts. In this research, each panel contribution was first analyzed to identify the panel that contributes the most to the target point. The proposed particle dampers were then attached to this panel for sound reduction. In the numerical process, a Particle Dampers Cyclic Iterative Method (PDCIM) was proposed for extracting the damping loss factor of the particle dampers to compute the sound pressure of a target point in the cavity with the particle dampers. For further comparative studies, simulation experiments are conducted for three cases: a case with the particle dampers, a case with the empty particle containers and a case with the equivalent mass. The numerical study found that the case with the particle dampers had the best sound reduction effect. Later, model tests were carried out to validate the numerical results. Experimental test results revealed that the particle dampers are remarkably effective for reducing the sound inside the enclosed cavity. [ABSTRACT FROM AUTHOR]

A set of orthogonal experiments using three factors (flushing pressure, flushing frequency, and flushing time) was used to study the anti-clogging performance of a patch-type dentation labyrinth-channel emitter. After irrigation, the change in the emitter discharge was tested, and the discharged particle size distribution was measured using a laser particle size analyser. The results showed that the flushing treatments had a significant effect on the anti-clogging performance of the emitter and extended the emitter's service life by 35.2% on average. Among the three factors, the flushing pressure lengthened the emitter's service life most. With more irrigation events, the discharged particle sizes V 10, V 50, and V 90 (i.e. the particle size with accumulating particle volumes of 10%, 50% and 90%, respectively) decreased under different flushing treatments. However, particle sizes were still larger than those without the flushing. Particles of all sizes could be trapped in the emitter channel. However, coarse particles were trapped more easily, which was the major reason for emitter clogging. Flushing treatments helped the discharge of sediments. The analysis of variance indicated that the flushing pressure had a significant effect on the discharge of coarse particles and flushing time had an obvious impact on fine particles. Elevating the flushing pressure was the major method to extend the life of emitters for water with large particles >18.04 μm diameter and extending the flushing time was the main way for water with particles <1.20 μm diameter. [ABSTRACT FROM AUTHOR]