Green coconut fiber (Cocos nucifera L.) has been largely used in solid-phase extraction. The effect of the initial dye concentration (1.91, 3.02 and 4.02) × 10-5 mol·L-1 and solid phase contact (SPE) time...Green coconut fiber (Cocos nucifera L.) has been largely used in solid-phase extraction. The effect of the initial dye concentration (1.91, 3.02 and 4.02) × 10-5 mol·L-1 and solid phase contact (SPE) time were evaluated at different temperatures (283, 298 and 313) K at pH 2. Kinetic experimental data were applied to three simplified kinetic models: pseudo-first order, pseudo-second order, and intraparticle diffusion. The adsorption of 5.5’-DI onto the solid phase showed excellent fit to the pseudo-second order model. At 283, 298 and 313 K the maximum sorption, qmax,exp, for the lowest initial concentration (Co = 1.91 × 10-5 mol·L-1) of 5.5’-DI were (5.01, 5.24 and 6.14) × 10-4 g·g-1;for Co = 3.02 × 10-5 mol·L-1 (0.93, 1.01 and 1.03) × 10-3展开更多
On August 6,2023,a magnitude MW5.5 earthquake struck Pingyuan County,Dezhou City,Shandong Province,China.This event was significant as no large earthquakes had been recorded in the region for over a century,and no act...On August 6,2023,a magnitude MW5.5 earthquake struck Pingyuan County,Dezhou City,Shandong Province,China.This event was significant as no large earthquakes had been recorded in the region for over a century,and no active fault had been previously identified.This study collects 1309 P-wave arrival times and 866 S-wave arrival times from 74 seismic stations less than 200 km to the epicenter to constrain the spatial distribution of the mainshock and its 125 early aftershocks by the double difference earthquake relocation method,and selects 864 P-waveforms from 288 stations located within 800 km of the epicenter to constrain the focal mechanism solution of the mainshock through centroid moment tensor inversion.The relocation and the inversion indicate,the Pingyuan MW5.5 earthquake was caused by a rupture on a buried fault,likely an extensive segment of the Gaotang fault.This buried fault exhibited a dip of approximately 75°to the northwest,with a strike of 222°,similar to the Gaotang fault.The rupture initiated at the depth of 18.6 km and propagated upward and northeastward.However,the ground surface was not broken.The total duration of the rupture was~6.0 s,releasing the scalar moment of 2.5895×1017 N·m,equivalent to MW5.54.The moment rate reached the maximum only 1.4 seconds after the rupture initiation,and the 90%scalar moment was released in the first 4.6 s.In the first 1.4 seconds of the rupture process,the rupture velocity was estimated to be 2.6 km/s,slower than the local S-wave velocity.As the rupture neared its end,the rupture velocity decreased significantly.This study provides valuable insights into the seismic characteristics of the Pingyuan MW5.5 earthquake,shedding light on the previously unidentified buried fault responsible for the seismic activity in the region.Understanding the behavior of such faults is crucial for assessing seismic hazards and enhancing earthquake preparedness in the future.展开更多
基金The authors are grateful to FAPESP 2010/18713-5,FAPESP 2011/21511-8 and CNPq Brazilian Foundations for the financial support.
文摘Green coconut fiber (Cocos nucifera L.) has been largely used in solid-phase extraction. The effect of the initial dye concentration (1.91, 3.02 and 4.02) × 10-5 mol·L-1 and solid phase contact (SPE) time were evaluated at different temperatures (283, 298 and 313) K at pH 2. Kinetic experimental data were applied to three simplified kinetic models: pseudo-first order, pseudo-second order, and intraparticle diffusion. The adsorption of 5.5’-DI onto the solid phase showed excellent fit to the pseudo-second order model. At 283, 298 and 313 K the maximum sorption, qmax,exp, for the lowest initial concentration (Co = 1.91 × 10-5 mol·L-1) of 5.5’-DI were (5.01, 5.24 and 6.14) × 10-4 g·g-1;for Co = 3.02 × 10-5 mol·L-1 (0.93, 1.01 and 1.03) × 10-3
基金support from the National Natural Science Foundation of China(Nos.42104043,42374081,and U2039208)the Fundamental Research Funds for the Institute of Geophysics,China Earthquake Administration(No.DQJB22R35).
文摘On August 6,2023,a magnitude MW5.5 earthquake struck Pingyuan County,Dezhou City,Shandong Province,China.This event was significant as no large earthquakes had been recorded in the region for over a century,and no active fault had been previously identified.This study collects 1309 P-wave arrival times and 866 S-wave arrival times from 74 seismic stations less than 200 km to the epicenter to constrain the spatial distribution of the mainshock and its 125 early aftershocks by the double difference earthquake relocation method,and selects 864 P-waveforms from 288 stations located within 800 km of the epicenter to constrain the focal mechanism solution of the mainshock through centroid moment tensor inversion.The relocation and the inversion indicate,the Pingyuan MW5.5 earthquake was caused by a rupture on a buried fault,likely an extensive segment of the Gaotang fault.This buried fault exhibited a dip of approximately 75°to the northwest,with a strike of 222°,similar to the Gaotang fault.The rupture initiated at the depth of 18.6 km and propagated upward and northeastward.However,the ground surface was not broken.The total duration of the rupture was~6.0 s,releasing the scalar moment of 2.5895×1017 N·m,equivalent to MW5.54.The moment rate reached the maximum only 1.4 seconds after the rupture initiation,and the 90%scalar moment was released in the first 4.6 s.In the first 1.4 seconds of the rupture process,the rupture velocity was estimated to be 2.6 km/s,slower than the local S-wave velocity.As the rupture neared its end,the rupture velocity decreased significantly.This study provides valuable insights into the seismic characteristics of the Pingyuan MW5.5 earthquake,shedding light on the previously unidentified buried fault responsible for the seismic activity in the region.Understanding the behavior of such faults is crucial for assessing seismic hazards and enhancing earthquake preparedness in the future.
