Clogging in the heat exchangers of the phosphoric acid concentration unit is a phenomenon which hinders the proper functioning of the installation. It results in the accumulation of undesirable solid deposits on the p...Clogging in the heat exchangers of the phosphoric acid concentration unit is a phenomenon which hinders the proper functioning of the installation. It results in the accumulation of undesirable solid deposits on the pipes and consequently a decrease of its performance. This deposit is mainly anhydrous or hemihydrate gypsum in addition to Na2SiF6. Phosphoric acid desulphation before its concentration step allows reducing this undesirable effect. Barium carbonate is used for the retention of sulphate ions using a simple experimental protocol which can easily be inserted into the phosphoric acid manufacturing. Four factors: quality of the phosphoric acid to be concentrated, amount of barium carbonate, temperature and time, were studied using design of experiment (DOE) methodology with two-level full factorial design strategy in order to assess their effects on desulphation. Only the first two factors have significant effects. Therefore, for effective sulphate removal, the validated statistical model (R2 = 99.96%) allows to predict the amount of barium carbonate to be used, depending on quality of the phosphoric acid to be concentrated and using the available temperature and time in the industrial process.展开更多
In order to treat the polluted discharge from El-Jadida,Morocco,a method of electrocoagulation using aluminum electrodes was used.This approach was coupled for the first time with high-frequency electrochemical impeda...In order to treat the polluted discharge from El-Jadida,Morocco,a method of electrocoagulation using aluminum electrodes was used.This approach was coupled for the first time with high-frequency electrochemical impedance spectroscopy(EIS).Significant pollutant abatementwas observed after 30 min,at a current density of 190.5 A·m^(-2),with a specific electrical energy consumption of 1.58 kW·h(per gram of eliminated carbon organic demand(COD))and specific aluminum consumption of 0.11 g·g^(-1):electrocoagulation proved to be particularly effective,achieving 85.7%elimination of COD and a decrease of total dissolved solid(TDS)and electrical conductivity(EC)levels from 2430 mg·L^(-1)to 1773 mg·L^(-1)and from 4230μS·cm^(-1)to 3210μS·cm^(-1),respectively.As for USP and ORP,they decreased from 2.5 to 1.87 and from 244.6 mV to 51 mV,respectively.The inductance of the electrocoagulation system measured by EIS was modeled through an electrical equivalent circuit.When the applied intensity increased,the coagulation resistance increased suddenly when the applied electrical current reached 0.2 A(current density:95.2 A·m^(-2)).At this point,the rate of COD abatement versus SEEC(specific electrical energy consumption decreases which shows that the EC process should be combined with another process to improve its efficiency,such as ultrasound.展开更多
Research on organic solar cells has a craze importance because they show very interesting properties including their flexibility and the opportunity to be made into large surfaces. However, their stability and perform...Research on organic solar cells has a craze importance because they show very interesting properties including their flexibility and the opportunity to be made into large surfaces. However, their stability and performance should be significantly improved compared to their current state. A nominal output of around 10% will be the goal for the coming years. The use of organic materials for photovoltaic applications is the subject of intense research in recent years. This work is based in part on the development of new conjugated polymers. In this paper, we present the synthesis and characterization of poly [(thiophene-2,5-diyl)-co-(benzylidene)] PTB catalysed by Maghnite-H+, used in the active layer of the solar cell organic heterojunction with PCBM (derivative of C60) was used as a junction of the solar cell: Glas/ITO/BCP/C60/PTB/Au/Al. A current density of short circuit of about Jcc 0.1mA/cm2 was obtained for this structure with a yield of around 0.15%.展开更多
In the present study, β-cyclodextrin-grafted chitosan nanoparticles (β-CD- g-CS NPs) were prepared using a new ionic gelation strategy involving a synergistic effect of NaCI (150 mmol/L), 4-(2-hydroxyethyl)-1-...In the present study, β-cyclodextrin-grafted chitosan nanoparticles (β-CD- g-CS NPs) were prepared using a new ionic gelation strategy involving a synergistic effect of NaCI (150 mmol/L), 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES, 10 mmol/L), and water bath sonication. This new strategy afforded smaller and more monodisperse β-CD-g-CS NPs vs. the classical ionic gelation method. New HA8β-CD-g-CS NPs were also prepared using the above-mentioned strategy by adding hyaluronic acid (HA) to the β-CD-g-CS copolymer at different weight ratios until the ZP values conversion. The best result was obtained with the weight ratio of w(HA):w(β-CD-g-CS) = 2:1 and furnished new spherical and smooth HA/β-CD-g-CS NPs. Furthermore, the stability of β- CD-g-CS NPs and HA/β-CD-g-CS NPs at 4℃ in physiological medium (pH 7.4) was compared for 3 weeks period and showed that HA/β-CD-g-CS NPs were more stable all maintaining their monodispersity and high negative ZP values compared to β-CD-g-CS NPs. Finally, preliminary study of HA/β-CD-g-CS NPs as carrier for the controlled release of the anticancer drug doxorubicin was investigated. These new HA/β-CD-g-CS NPs can potentially be used as drug delivery and targeting systems for cancer treatment.展开更多
文摘Clogging in the heat exchangers of the phosphoric acid concentration unit is a phenomenon which hinders the proper functioning of the installation. It results in the accumulation of undesirable solid deposits on the pipes and consequently a decrease of its performance. This deposit is mainly anhydrous or hemihydrate gypsum in addition to Na2SiF6. Phosphoric acid desulphation before its concentration step allows reducing this undesirable effect. Barium carbonate is used for the retention of sulphate ions using a simple experimental protocol which can easily be inserted into the phosphoric acid manufacturing. Four factors: quality of the phosphoric acid to be concentrated, amount of barium carbonate, temperature and time, were studied using design of experiment (DOE) methodology with two-level full factorial design strategy in order to assess their effects on desulphation. Only the first two factors have significant effects. Therefore, for effective sulphate removal, the validated statistical model (R2 = 99.96%) allows to predict the amount of barium carbonate to be used, depending on quality of the phosphoric acid to be concentrated and using the available temperature and time in the industrial process.
基金financial support from POC4 allergies project(768686)which received funding from ERA PerMed ERA-NET,and the financial support from Bionanosens project(951887)which received funding from the European Union's Horizon 2020.
文摘In order to treat the polluted discharge from El-Jadida,Morocco,a method of electrocoagulation using aluminum electrodes was used.This approach was coupled for the first time with high-frequency electrochemical impedance spectroscopy(EIS).Significant pollutant abatementwas observed after 30 min,at a current density of 190.5 A·m^(-2),with a specific electrical energy consumption of 1.58 kW·h(per gram of eliminated carbon organic demand(COD))and specific aluminum consumption of 0.11 g·g^(-1):electrocoagulation proved to be particularly effective,achieving 85.7%elimination of COD and a decrease of total dissolved solid(TDS)and electrical conductivity(EC)levels from 2430 mg·L^(-1)to 1773 mg·L^(-1)and from 4230μS·cm^(-1)to 3210μS·cm^(-1),respectively.As for USP and ORP,they decreased from 2.5 to 1.87 and from 244.6 mV to 51 mV,respectively.The inductance of the electrocoagulation system measured by EIS was modeled through an electrical equivalent circuit.When the applied intensity increased,the coagulation resistance increased suddenly when the applied electrical current reached 0.2 A(current density:95.2 A·m^(-2)).At this point,the rate of COD abatement versus SEEC(specific electrical energy consumption decreases which shows that the EC process should be combined with another process to improve its efficiency,such as ultrasound.
基金the National Agency for Development and Research of Algeria for the financial support.
文摘Research on organic solar cells has a craze importance because they show very interesting properties including their flexibility and the opportunity to be made into large surfaces. However, their stability and performance should be significantly improved compared to their current state. A nominal output of around 10% will be the goal for the coming years. The use of organic materials for photovoltaic applications is the subject of intense research in recent years. This work is based in part on the development of new conjugated polymers. In this paper, we present the synthesis and characterization of poly [(thiophene-2,5-diyl)-co-(benzylidene)] PTB catalysed by Maghnite-H+, used in the active layer of the solar cell organic heterojunction with PCBM (derivative of C60) was used as a junction of the solar cell: Glas/ITO/BCP/C60/PTB/Au/Al. A current density of short circuit of about Jcc 0.1mA/cm2 was obtained for this structure with a yield of around 0.15%.
文摘In the present study, β-cyclodextrin-grafted chitosan nanoparticles (β-CD- g-CS NPs) were prepared using a new ionic gelation strategy involving a synergistic effect of NaCI (150 mmol/L), 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES, 10 mmol/L), and water bath sonication. This new strategy afforded smaller and more monodisperse β-CD-g-CS NPs vs. the classical ionic gelation method. New HA8β-CD-g-CS NPs were also prepared using the above-mentioned strategy by adding hyaluronic acid (HA) to the β-CD-g-CS copolymer at different weight ratios until the ZP values conversion. The best result was obtained with the weight ratio of w(HA):w(β-CD-g-CS) = 2:1 and furnished new spherical and smooth HA/β-CD-g-CS NPs. Furthermore, the stability of β- CD-g-CS NPs and HA/β-CD-g-CS NPs at 4℃ in physiological medium (pH 7.4) was compared for 3 weeks period and showed that HA/β-CD-g-CS NPs were more stable all maintaining their monodispersity and high negative ZP values compared to β-CD-g-CS NPs. Finally, preliminary study of HA/β-CD-g-CS NPs as carrier for the controlled release of the anticancer drug doxorubicin was investigated. These new HA/β-CD-g-CS NPs can potentially be used as drug delivery and targeting systems for cancer treatment.