27 research outputs found
Use of carbon materials for produced water treatment: a review on adsorption process and performance
The oil and gas production is identified by consuming a large amount of water and generating massive produced
water. The produced water is either reinjected into the underground layers or released into the rivers and oceans that
can cause severe damage to the environment due to toxic elements such as salts, oil and grease, and polyaromatic
hydrocarbons. So produced water treatment and management can reduce the significant threats to the soil and water
resources and solve the lack of water in different water-consuming sectors. During the last decades, adsorption
methods, such as using expanded graphite and activated carbon materials, have attracted scientistsâ attention because
these adsorbents are cost-effective and practical. This study aimed to review expanded graphiteâs synthesis, adsorption process, and efficient factors in removing heavy oil, heavy metals, benzene, toluene, ethylbenzene, and xylenes,
and organic acids from produced water and compare with other adsorbents, including activated carbon and residual
biomass. Based on the results of extensive research works, expanded graphiteâs high adsorption feature suggested
that graphite can be a promising adsorbent in actual produced water treatment
Digital adaptive timing and energy measurement of BaF2 and LaBr3 scintillator events
The paper presents a mixed analog-digital
configurable instrument for processing signals from different type
of scintillation detectors. We discuss design, realization and
firmware structure of the system. We mainly present preliminary
result obtained with the use LaBr3 detectors.
The main feature of the architecture is the adaptability to a
wide range of different operative conditions by changing
configuration both of the digital and of the analog section. Using
modular hardware and firmware architecture and digital
configurable devices (a digital signal processor \u2013DSP and a field programmable gate array \u2013 FPGA) it\u2019s possible to achieve optimum performance in an extremely wide range of application
Digital Adaptive Timing and Energy Measurement of BaF2 and LaBr3 Scintillator Events
none8Pubblicazione su CDROMS. BRAMBILLA; F. CAMERA; M. CUCCARESE; A. GERACI; B. MILLION; S. RIBOLDI; M. SASSI; S. SCARPACIS., Brambilla; F., Camera; M., Cuccarese; Geraci, Angelo; B., Million; S., Riboldi; M., Sassi; Scarpaci, SEBASTIANO ANTONI
Removal of diclofenac from aqueous solutions by adsorption on thermo-plasma expanded graphite
The adsorption of diclofenac on thermo-plasma expanded graphite (a commercial product) from water solutions was investigated. The adsorbent material was characterized by SEM, TEM, BET, Raman and X-ray diffraction analyses. Typical diffractogram and Raman spectrum of graphitic material, dimension of 24.02 nm as crystallite dimension and a surface area of 47 m2 gâ1 were obtained. The effect of pH on the adsorption capacity was evaluated in the range 1â7 and the adsorption mechanism was described by kinetic and isothermal studies. Pseudo-second order and DubininâRadushkevich models agreed with theoretical values of adsorption capacity (i.e. 400 and 433 mg gâ1, respectively) and resulted to be the best fit for kinetics and isothermal experimental data. The thermodynamics of the process was evaluated by plotting the adsorption capacity/concentration ratio at the equilibrium as a function of different values of the multiplicative inverse of temperature. Moreover, the adsorbent regeneration was also investigated, comparing two different remediation techniques. Solvent washing performed with NaOH 0.2 M and thermo-treatment carried out by heating in an oven at 105 °C for 2 h and then at 200 °C for 4 h. The thermo-treatment was the best technique to regenerate the adsorbent, ensuring same performance after 4 cycles of use and regeneration
Sustainable Adsorbent Material Prepared by Soft Alkaline Activation of Spent Coffee Grounds: Characterisation and Adsorption Mechanism of Methylene Blue from Aqueous Solutions
Dyes are emerging as hazardous pollutants, which are the primary challenges for environmentalists. Dye removal from effluents is urgently needed. Adsorption technology has been widely employed in this context as an effective method for removing colours from the aqueous phase, and adsorption with the use of low-cost adsorbents has been shown to be more successful on a larger scale than other methods. In this study, spent coffee grounds (SCGs) were used as the precursor for the preparation of a low-cost activated carbon through the chemical activation with NaOH. The SCG sample was impregnated with NaOH and carbonised at 300 °C for three hours. Its morphological and physical-chemical properties were assessed using scanning electron microscopy (SEM), X-ray diffraction, and Raman spectroscopy analyses. The performance of the treated SCG as an adsorbent material for methylene blue (MB) was evaluated by analysing the effect of the initial pH ionic strength on the adsorption capacity and by evaluating the kinetics and the mechanisms of the process (using adsorption isotherms). The effect of the initial concentration (500 and 250 mg Lâ1) of MB on the kinetics of the process and the impact of the initial pH (7.5 and 6) on the adsorption isotherm were evaluated. The obtained results show that the pseudo-second order model controls the process for both the investigated initial concentration and the adsorption capacity, which are 142.8 and 113.6 mg Lâ1, respectively. The results indicate that the pH value influences the adsorption isotherm model that regulates the process. Specifically, this process is regulated by the Temkinâs model with a pH of 7.5 and by the Langmuirâs model with a pH of 6. The thermodynamics of the process were also determined. The results show that SCG, treated and carbonised by soft alkaline activation, is a promising low-cost adsorbent material as its performance is comparable to that of conventional active carbon materials
Time to digital converter implementation on a configurable digital processor for scintillation detector events
Removal of organic micropollutants from water by adsorption on thermoâplasma expanded graphite encapsulated into calcium alginate
Nowadays, public concern is focused on the degradation of water quality. For this reason, the development of innovative
technologies for water treatment in view of (micro)pollutant removal is important. Indeed, organic (micro)pollutants, such as pharmaceuticals, herbicides, pesticides and plasticizers at concentration levels of ÎŒg Lâ1 or even ng Lâ
1 are hardly removed during conventional wastewater treatment. In view of this, thermo-plasma expanded graphite, a light-weight innovative material in the form of a powder, was encapsulated into calcium alginate to obtain a granular form useful as filtration and adsorption material for removal of different pollutants. The produced material was used to remove atrazine, bisphenol-A, 17-α-ethinylestradiol and carbamazepine (at concentration levels of 125, 250 and 500 ÎŒg Lâ1) by top-down filtration. The effect of flow rate, bed depth and adsorbent composition was evaluated based on breakthrough curves. The experimental data was analysed with the Adams-Bohart model in view of scale-up. Under optimal conditions, removal and adsorption capacity of respectively about 21%, 21%, 38%,42%, 43 ÎŒg gâ1, 44 ÎŒg gâ1, 37 ÎŒg gâ1 and 87 ÎŒg gâ1 were obtained for atrazine,
bisphenol, 17-α ethinylestradiol and carbamazepine when using 0.12 g of thermo-plasma expanded graphite to treat 200 mL at 500 ÎŒg Lâ1 (for each compound) of solution obtaining at contact time of 20 min. The granular form of TPEG obtained
(GTPEG) by entrapping in calcium alginate results to have a good adsorbent property for the removal of carbamazepine, atrazine, bisphenol A and 17-α ethinylestradiol from water at concentration levels between 250 and 500 ÎŒg Lâ
1. Promising results confirm the adsorbent properties of TPEG and push-up us to investigate on its application and improve of its performance by evaluating different entrapping materials
Time to Digital converter implementation on a configurable digital processor for BaF2 scintillation detector events
reserved8Pubblicazione su CDROM - N30 - 10
INFN
CittĂ Editore Piscataway USAS. SCARPACI;S. BRAMBILLA;F. CAMERA;A. GERACI;B. MILLION;S. RIBOLDI;M. CUCCARESE;S. CARAMANNOScarpaci, SEBASTIANO ANTONIN; S., Brambilla; F., Camera; Geraci, Angelo; B., Million; S., Riboldi; M., Cuccarese; S., Caramann
Divergent Synthesis of Dihydropyranone Stereoisomers via NâHeterocyclic Carbene Catalysis
In vivo imaging reveals a tumor-associated macrophage-mediated resistance pathway in anti-PD-1 therapy
Monoclonal antibodies (mAbs) targeting the immune checkpoint anti-programmed cell death protein 1 (aPD-1) have demonstrated impressive benefits for the treatment of some cancers; however, these drugs are not always effective, and we still have a limited understanding of the mechanisms that contribute to their efficacy or lack thereof. We used in vivo imaging to uncover the fate and activity of aPD-1 mAbs in real time and at subcellular resolution in mice. We show that aPD-1 mAbs effectively bind PD-1+ tumor-infiltrating CD8+ T cells at early time points after administration. However, this engagement is transient, and aPD-1 mAbs are captured within minutes from the T cell surface by PD-1- tumor-associated macrophages. We further show that macrophage accrual of aPD-1 mAbs depends both on the drug's Fc domain glycan and on FcÎł receptors (FcÎłRs) expressed by host myeloid cells and extend these findings to the human setting. Finally, we demonstrate that in vivo blockade of FcÎłRs before aPD-1 mAb administration substantially prolongs aPD-1 mAb binding to tumor-infiltrating CD8+ T cells and enhances immunotherapy-induced tumor regression in mice. These investigations yield insight into aPD-1 target engagement in vivo and identify specific Fc/FcÎłR interactions that can be modulated to improve checkpoint blockade therapy