Adsorptive removal of BTEX compounds from wastewater using activated carbon derived from macadamia nut shells

In this study, adsorptive removal of benzene, toluene, ethylbenzene and xylenes (BTEX) from synthetic water using activated carbon adsorbent derived from macadamia nut shells was investigated. The surface  functional groups of the synthesized adsorbents were assessed by Fourier transform infrared spectra. The specific surface area, pore size and pore volume at 77 K nitrogen adsorption, surface morphology, and the crystalline structure of the adsorbents were determined using Brunauer-Emmett-Teller, scanning electron microscopy and x-ray diffraction, respectively. Batch adsorption mode was used to evaluate the performance of the activated carbon. The stock solutions of synthetic wastewater were prepared by dissolving 100 mg/L of each of the BTEX compound into distilled water in a 250 mL volumetric flask. Effect of initial concentration of BTEX compounds, contact time, and mass of adsorbent on the removal of BTEX compounds from the synthetic wastewater was investigated. The macadamia nut shell–derived activated carbon (MAC) proved to be an effective adsorbent for BTEX compounds, with a large surface area of 405.56 m2/g. The exposure time to reach equilibrium for maximum removal of BTEX was observed to be 20 min. The adsorption capacity of the BTEX compounds by MAC followed the following adsorption order: benzene > toluene > ethylbenzene > xylene.&nbsp

Proof of concept for wind turbine wake investigations with the RPAS SUMO

The Small Unmanned Meteorological Observer (SUMO) has been operated in the vicinity of five research turbines of the Energy Research Centre of the Netherlands (ECN) at the test site Wieringermeer. The intention of the campaign was to proof the capability of the system for wind turbine wake investigations also for situations above rated wind speed. In rather high wind conditions of 15-20 ms−1 on May 10, 2014, the system showed a satisfying in-flight behavior and performed five racetrack flights. The racetrack patterns flown parallel to the row of the five turbines (four flights downstream the turbine row, one upstream) enable the characterization and investigation of the strength, i.e. the reduction in the mean wind, and structure, i.e. the horizontal extension and turbulent kinetic energy (TKE) distribution of single turbine wakes.publishedVersio

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Adsorptive removal of BTEX compounds from wastewater using activated carbon derived from macadamia nut shells

In this study, adsorptive removal of benzene, toluene, ethylbenzene and xylenes (BTEX) from synthetic water using activated carbon adsorbent derived from macadamia nut shells was investigated. The surface functional groups of the synthesized adsorbents were assessed by Fourier transform infrared spectra. The specific surface area, pore size and pore volume at 77 K nitrogen adsorption, surface morphology, and the crystalline structure of the adsorbents were determined using Brunauer-Emmett-Teller, scanning electron microscopy and x-ray diffraction, respectively. Batch adsorption mode was used to evaluate the performance of the activated carbon.&nbsp; The stock solutions of synthetic wastewater were prepared by dissolving 100 mg/L of each of the BTEX compound into distilled water in a 250 mL volumetric flask. Effect of initial concentration of BTEX compounds, contact time, and mass of adsorbent on the removal of BTEX compounds from the synthetic wastewater was investigated. The macadamia nut shell–derived activated carbon (MAC) proved to be an effective adsorbent for BTEX compounds, with a large surface area of 405.56 m2/g. The exposure time to reach equilibrium for maximum removal of BTEX was observed to be 20 min.&nbsp; The adsorption capacity of the BTEX compounds by MAC followed the following adsorption order: benzene &gt; toluene &gt; ethylbenzene ˃ xylene

Proof of concept for wind turbine wake investigations with the RPAS SUMO

The Small Unmanned Meteorological Observer (SUMO) has been operated in the vicinity of five research turbines of the Energy Research Centre of the Netherlands (ECN) at the test site Wieringermeer. The intention of the campaign was to proof the capability of the system for wind turbine wake investigations also for situations above rated wind speed. In rather high wind conditions of 15-20 ms−1 on May 10, 2014, the system showed a satisfying in-flight behavior and performed five racetrack flights. The racetrack patterns flown parallel to the row of the five turbines (four flights downstream the turbine row, one upstream) enable the characterization and investigation of the strength, i.e. the reduction in the mean wind, and structure, i.e. the horizontal extension and turbulent kinetic energy (TKE) distribution of single turbine wakes

Fabrication and performance evaluation of tannin iron complex (TA-FeIII/PES) UF membrane in treatment of BTEX wastewater

Oil exploration generates produced water that is characterized as hazardous and toxic waste. Produced water contains a mixture of various pollutants, including monoaromatic hydrocarbons BTEX (benzene, toluene, ethylbenzene, and xylene), compounds that are carcinogenic even in small concentrations.&nbsp; In this study, tannin iron complex (TA-FeIII), blended into polyethersulfone (PES) membrane was evaluated for the treatment of BTEX-containing wastewater. The membranes were fabricated using the non-solvent induced phase separation (NIPS) method and loading of the TA-FeIII complex on the membranes varied from 0–0.9 wt%. The fabricated membranes were characterized using various techniques such as scanning electron microscopy (SEM), water contact angle (WCA), Fourier transform infrared (FTIR) spectroscopy, and atomic force microscopy (AFM) to check the surface morphology, hydrophilicity, surface functionality and surface roughness of the fabricated membranes, respectively. The TA-FeIII modified membranes showed increased pure water flux from 100 (PES 0) to ∼150 (PES 0.9) L/(m2‧h) at 100 kPa. The performance of the fabricated membranes was tested using 70 mg/L synthetic BTEX solution. Overall BTEX rejection &gt; 70% was achieved at increasing TA-FeIII loadings compared to BTEX rejection &lt; 65% for the pure PES membrane. Rejection of the BTEX compounds was mainly through the size exclusion mechanism. These modified TA-FeIII/PES UF membranes proved to be effective in the treatment of BTEX-containing water, and also have the potential to be applied in oily wastewater treatment.&nbsp