New Paper (URADTE CRAPC):Artificial neural network modeling of cefixime photodegradation by synthesized CoBi2O4 nanoparticles

New Paper (URADTE CRAPC):Artificial neural network modeling of cefixime photodegradation by synthesized CoBi2O4 nanoparticles

À LA UNE, CRAPC News, Publication Scientifique, Publication Scientifique Division Santé, URADTE
  • Oussama Baaloudj, Laboratory of Reaction Engineering, Faculty of Mechanical Engineering and Process Engineering USTHB, BP 32, Algiers, Algeria
  • Noureddine Nasrallah, Laboratory of Reaction Engineering, Faculty of Mechanical Engineering and Process Engineering USTHB, BP 32, Algiers, Algeria
  • Mohamed Kebir, Laboratory of Reaction Engineering, Faculty of Mechanical Engineering and Process Engineering USTHB, BP 32, Algiers, Algeria
  • Research Unit on Analysis and Technological Development in Environment (URADTE-CRAPC), BP 384, Bou-Ismail Tipaza, Algeria
  • Bouzid Guedioura, Reactor division, Nuclear Research Center, Draria, Algeria
  • Abdeltif Amrane, Univ Rennes – ENSCR / UMR CNRS 6226 “Chemical Sciences of Rennes” ENSCR, Campus de Beaulieu, 11, allée de Beaulieu – CS 50837 – 35708 Rennes, 35708, Rennes, France
  • Phuong Nguyen-Tri, Institute of Research and Development, Duy Tan University, Da Nang, 550000, Vietnam
  • Université du Québec à Trois-Rivières (UQTR), Trois-Rivières, Québec, G9A 5H7, Canada
  • Sonil Nanda & Aymen Amin Assadi Department of Chemical and Biological Engineering, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5A9, Canada

Received: 8 August 2020 /Accepted: 16 November 2020

© 2020 Springer Nature Switzerland AG. Part of Springer Nature

  • Environmental Science and Pollution Research

Abstract

CoBi2O4 (CBO) nanoparticles were synthesized by sol-gel method using polyvinylpyrrolidone (PVP) as a complexing reagent. For a single phase with the spinel structure, the formed gel was dried and calcined at four temperatures stages. Various methods were used to identify and characterize the obtained spinel, such as X-ray diffraction (XRD), scanning electron micrograph (SEM-EDX), transmission electron microscope (TEM), Fourier transform infrared (FT-IR), X-ray fluorescence (XRF), Raman, and UV-Vis spectroscopies. The photocatalytic activity of CBO was examined for the degradation of a pharmaceutical product cefixime (CFX). Furthermore, for the prediction of the CFX degradation rate, an artificial neural network model was used. The network was trained using the experimental data obtained at different pH with different CBO doses and initial CFX concentrations. To optimize the network, various algorithms and transfer functions for the hidden layer were tested. By calculating the mean square error (MSE), 13 neurons were found to be the optimal number of neurons and produced the highest coefficient of correlation R2 of 99.6%. The relative significance of the input variables was calculated, and the most impacting input was proved to be the initial CFX concentration. The effects of some scavenging agents were also studied. The results confirmed the dominant role of hydroxyl radical OH in the degradation process. With the novel CoBi2O4/ZnO hetero-system, the photocatalytic performance has been enhanced, giving an 80% degradation yield of CFX (10 mg/L) at neutral pH in only 3 h.

© 2020 Springer Nature Switzerland AG. Part of Springer Nature

https://link.springer.com/article/10.1007/s11356-020-11716-w

New Paper CRAPC:Porous Silica Monolithic Polymers for Micromachined Gas Chromatography Columns: A Featured Phase for Fast and Efficient Separations of Light Compounds Mixtures

New Paper CRAPC:Porous Silica Monolithic Polymers for Micromachined Gas Chromatography Columns: A Featured Phase for Fast and Efficient Separations of Light Compounds Mixtures

À LA UNE, CRAPC News, Publication Scientifique, Publication Scientifique Division Santé

Published in: IEEE Sensors Journal ( Volume: 20, Issue: 22, Nov.15, 15 2020)

Porous Silica Monolithic Polymers for Micromachined Gas Chromatography Columns: A Featured Phase for Fast and Efficient Separations of Light Compounds Mixtures

Authors


Imadeddine Azzouz

ESIEE Engineering, Noisy-le-Grand, France

Research Centre in Analytical Chemistry and Physics (CRAPC), Algiers, Algeria

Djahida Lerari

Materials Chemistry Division, Research Centre in Analytical Chemistry and Physics (CRAPC), Algiers, Algeria

Khaldoun Bachari

Research Centre in Analytical Chemistry and Physics (CRAPC), Algiers, Algeria

Abstract:

Since the late 1970s, approaches have been proposed to replace conventional gas chromatography apparatus with silicon-based microfabricated separation systems. Performances are expected to be much improved with miniaturization owing to the reduction of diffusion distances and better thermal management. When it is easy to microfabricate miniaturized parts, the main challenge consists, however, to produce stable, efficient, and functionalized columns. The purpose of the paper is to transpose and adapt monolith synthesis in-situ micromachined gas chromatography columns. Silica-based monolithic microcolumns based on the sol–gel process were tested in the course of high-speed gas chromatographic separations of light hydrocarbons mixture (C1–C4). At the optimum separation conditions, a very good resolution (2.14) for very light compounds (C1–C2) was reached on a 50 cm microcolumn at room temperature with a back-pressure within the range used at gas chromatography facilities (without external modification of the device). The versatility of these microelectromechanical systems (MEMS) columns was demonstrated with a high-temperature C1 – C2 separation, and unsaturated cyclic alkanes. Light halogenated alkanes were also successfully separated. These columns should be used in various applications related to oil/gas and environment field analyses.

https://ieeexplore.ieee.org/abstract/document/9130702/authors

New Paper CRAPC : Spherical NiCu phyllosilicate photocatalysts for hydrogen generation

New Paper CRAPC : Spherical NiCu phyllosilicate photocatalysts for hydrogen generation

À LA UNE, Publication Scientifique, Publication Scientifique Division Santé

International Journal of Hydrogen Energy

Available online 18 November 2020

Spherical NiCu phyllosilicate photocatalysts for hydrogen generation

Author links open overlay panel

Imane Ghiata Adel Saadia Khaldoun Bacharib Neil J.Covillec Amel Boudjemaaab

a Laboratory of Natural Gas, Faculty of Chemistry, USTHB, Algiers, Algeria

b Centre de Recherche Scientifique et Technique en Analyses Physico-Chimiques, Bou-Ismail CP, 42004, Tipaza, Algeria

c DSI-NRF Centre of Excellence in Strong Materials and the Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Johannesburg, 2050, South Africa

Abstract

To enhance the photocatalytic performance of semiconductors, a highly active and durable SiO2@xNiCuPS photocatalyst was evaluated for photocatalytic hydrogen generation. The photocatalyst was prepared by a hydrothermal method using SiO2 spheres, and a 1:1 Cu:Ni mixture (5 and 10 wt%). The reaction gave a highly stable phyllosilicate material with a core@shell structure. The materials were characterized by a range of techniques. DRS data revealed indirect optical transitions at 1.5 eV and 2.75 eV for the SiO2@5NiCuPS and SiO2@10NiCuPS materials. The new photocatalysts were successfully tested for hydrogen generation under visible irradiation to give H2 yields of 184 and 47 μmol g−1. min−1 for SiO2@5NiCuPS and SiO2@10NiCuPS, respectively. The data suggest that the enhanced activity of adding Cu to Ni to form Ni/Cu phyllosilicates is not due to NiCu alloy formation but due to changes in the support morpholohgy brought about by metal-support interactions. The catalysts were stable over 4 repeat reaction cycles.

Keywords

Hydrogen Photocatalysis NiCu nanoparticles core@shell material

https://www.sciencedirect.com/science/article/abs/pii/S0360319920340817?fbclid=IwAR1vgDZPfcyH0LxEy92jKtUJrHV4yapXR0f0jCYACoYiz9Y_KCRF45WrOGc

Impact of freezing and drying preprocessing on pigments extraction from the brown seaweed «phyllaria reniformis» collected in algerian coast

Publication Scientifique

H. MOKRANE, N. GHALIAOUI, M. HAZZIT, M. HADJADJ, F-S OTMANI, S. TOUATI, H. SERIDI

Carpathian Journal of Food Science and Technology

Received:
5 January 2019
Accepted:
15 August 2020

ABSTRACT
Seaweeds are an excellent source of natural pigments such as chlorophylls
and carotenoids that exhibit several bioactive properties fully exploited in
food and health products. Due to the high sensitivity and the rapid
degradation of pigments, recent researches are now focusing on
development of efficient techniques for their extraction, while the sample
preprocessing as the main important step attracted less attention. The
objective of this study was the evaluation of the effect of freezing and drying
preprocessing on pigments quantity, quality and antioxidant activity of the
brown seaweed Phyllaria reniformis. Pigments were quantified using UVVisible spectrophotometry and fully characterized by reverse phase high
performance liquid chromatography (RP-HPLC). Phyllaria reniformis was
characterized by a high amount of pigments especially fucoxanthin. Based
on UV-visible spectrophotometry results, alga preprocessing before
extraction showed a high variability on pigments content. As shown by RPHPLC freezing preprocessing exhibited the most efficient pigment
extraction in term of quantity. While, drying preprocessing demonstrated
higher amount of β-carotene and pheophytin a. The highest and most
efficient antioxidant activities were obtained in the frozen samples. The
quality, quantity and antioxidant activities of Phyllaria reniformis pigments
extract was found to be deeply related to the preprocessing step

Keywords:
Preprocessing
Freezing
Drying
Phyllaria reniformis
Pigments


https://doi.org/10.34302/crpjfst/2020.12.3.6

Contribution à la valorisation des dattes (Deglet-Nour) dans la fabrication du fromage de chèvre

Publication Scientifique

N. FEDALA, M. MOKHTARI, L. MEKIMENE

Revue Agrobiologia

(2020), 10(1): 1918-28.

Reçu le 30/11/2019, Révisé le 09/06/2020, Accepté le 12/06/2020

Résumé
Description du sujet : Les progrès réalisés dans le domaine de la fabrication fromagère correspondent pour la
plupart aux efforts de recherche entrepris au cours du dernier siècle.
Objectifs : Formulation de fromages aux caractéristiques organoleptiques spécifiques, en combinant les bienfaits
du lait de chèvre et du fruit du dattier (Phoenix dactylifera L.).
Méthodes : Un fromage frais et un fromage à pâte pressée sont fabriqués. Les différentes analyses physicochimiques et microbiologiques sont réalisées pour le lait, et les fromages. L’analyse sensorielle est effectuée, les
dégustateurs ont été invités à noter leur préférence en utilisant des fiches de dégustation.
Résultats : L’EST est de 35 % pour les fromages frais et de 60 % pour les fromages à pâte pressée. La teneur en
G/S est de 42,85 % pour les fromages frais et de 38,33% pour les pâtes pressées. D’autre part, la teneur minimale
en protéines est de 25 % pour le fromage frais et de 31,35 % pour la pâte pressée. L’analyse microbiologique a
révélé l’absence de germe pathogène. La persistance de l’arôme des dattes est plus marquée pour les deux types
de dégustateurs.
Conclusion : Les fromages fabriqués présentent des caractéristiques organoleptiques spécifiques avec une
possibilité de les extrapoler en industrie laitière.

Mots clés : Deglet-Nour, lait de chèvre, produit du terroir, fromage.

Leaf organic content variation of 2 durum wheat genotypes under water stress by applying phytohormone (IAA)

Publication Scientifique

A. BENDJAMA , S. RAMDANI

African Journal of Agricultural Research

  Received: 05 May 2020   Accepted: 10 September 2020   Published: 31 October 2020

Abstract

Water stress is the most important problem in plant growth and development. Greenhouse trial is carried out on 2 durum wheat (Triticum durum Desf) genotypes (MBB and WAHA), to evaluate the effect of water stress on the biochemical content of leaves, and the possibility of reducing this effect by applying a growth regulator Indole-3-acetic acid (IAA) by seeds soaking and foliar spraying. Water stress causes a large accumulation of proline and soluble sugars and a decrease in the chlorophyll content of the leaves. The results obtained show that the effect of the hormone on the above-mentioned parameters is different according to the genotype and the mode of treatment, as well as the growth phase of the plant, without being able to promote application by soaking or spraying. The application of IAA has relatively reduced the effect of water stress by promoting the synthesis of proline and soluble sugars as osmotic regulators, and by increasing the chlorophyll content of the leaves. proline and soluble sugars concentrations showed negative and significant correlations with those of total chlorophyll. Our present study highlights some biochemical responses of plants to tolerate a water deficit and the possible involvement of exogenus application of IAA, as a phytohormone, in these regulatory mechanisms.

Key words: Triticum durum Desf, water stress, Indole-3-acetic acid (IAA), seed soaking, foliar spraying.

Proton transfer reaction confined within carbon nanotubes: Density functional theory and quantitative structure–property relationship analysis

Publication Scientifique

B. ACHOURI, Y. BELMILOUD, M. BRAHIMI

Reaction Kinetics and Mechanism

First Published September 18, 2019 Research Article

Abstract

In this work, we focus our attention on chemical reactions confined within carbon nanotubes. As a result of the confinement within carbon nanotubes, novel physical and chemical properties are found for the confined materials. We consider the feasibility of proton transfer inside carbon nanotubes. To do that, we have chosen formamide as the simplest real model for exhibiting the tautomerization in DNA. We have used the quantitative structure–property relationship method, based on geometry optimization and quantum chemical structural descriptors, to illustrate the potential of using the confined space inside carbon nanotubes, which will provide comprehensive information about carbon nanotubes. All calculations have been carried out using density functional theory quantum calculations with the B3LYP functional. The geometries optimized by the Gaussian program were transferred to the computer software DRAGON to calculate pertinent descriptors that could be used in the quantitative structure–property relationship model.

Keywords Proton transfercarbon nanotubesformamideDNAtautomerizationquantitative structure–property relationshipdensity functional theoryONIOM

https://doi.org/10.1177/1468678319864473

Electrocatalytic performance of Pt–Ni nanoparticles supported on an activated graphite electrode for ethanol and 2-propanol oxidation

Publication Scientifique

M-L. CHELAGHMIA, M. NACEF, H. FISLI, A-M. AFFOUNE, M. PONTIE, A. MAKHLOUF, T. DERABLA, O. KHELIFIand F. AISSAT

The Royal Society of Chemistry

Received 26th August 2020 , Accepted 26th September 2020

Abstract

Platinum (Pt) and platinum–nickel (Pt–Ni) electrocatalysts were prepared on activated graphite electrodes by an electrochemical deposition process. The electrocatalysts were analyzed by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The electrocatalytic activity of the prepared electrocatalysts, their stability, and the effect of temperature toward ethanol and 2-propanol oxidation were evaluated by cyclic voltammetry (CV), chronoamperometry and electrochemical impedance spectroscopy (EIS). The results showed that the Pt–Ni/C exhibited higher catalytic activity, better stability and better tolerance to poisoning by ethanol and 2-propanol oxidation intermediate species compared to Pt/C, which was interpreted as synergistic and electronic effects between Pt and Ni. A study of the temperature dependence of ethanol and 2-propanol oxidation in the temperature range of 298–318 K, shows that the apparent activation energy for ethanol and 2-propanol oxidation on Pt–Ni/C was lower than on Pt/C. The results also revealed that the electro-oxidation of ethanol and 2-propanol on Pt/C were improved by raising the temperature and Ni modification.

DOI: 10.1039/D0RA07331H

Synthesis of Amphiphilic Diblock Copolymer and Study of Their Self-assembly in Aqueous Solution

Publication Scientifique

W. CHAIBI, K. GUEMRA

Published online: 03 Aug 2020

Journal of Inorganic and Organometallic Polymers and Materials

Abstract

This paper describes the synthesis of novel amphiphilic diblock copolymer composed of polystyrene (PS) as the hydrophobic block and Poly(N-[3-(dimethylamino)propyl] methacrylamide) (PDMAPMA) as hydrophilic block by reverse-mode iodine transfer controlled radical polymerization (RITP). Initially, homopolymer based on activated monomers (styrene) was synthesized by RITP. Thereafter, amphiphilic diblock copolymer was synthesized. The diblock copolymer obtained was characterized by spectroscopic methods: FTIR, 1H NMR, 13C NMR, Energy-dispersive X-ray spectroscopy (EDX) to analyze the elemental composition. Their thermal behaviour was investigated by thermogravimetric analysis (TGA). Study of the self-organization in aqueous phase of the amphiphilic copolymer revealed that formation of micelles for concentrations was higher than critical aggregation concentration (CAC) which their values were determined by tensiometry. The self-assembly behaviors of this copolymer was studied in aqueous solution at different concentrations, PH and temperatures using Dynamic light scattering (DLS).

DOI: https://doi.org/10.1007/s10904-020-01464-2

Antimalarial-agent artemisinin and derivativesportray more potentbinding to Lys353 and Lys31-binding hotspots of SARS-CoV-2 spikeproteinthanhydroxychloroquine: potentialrepurposing of artenimol for COVID-19

Publication Scientifique

M. SEHAILIA ,  S. CHEMAT

Received 21 Apr 2020, Accepted 06 Jul 2020, Published online: 22 Jul 2020


Journal», Journal of Biomolecular Structure and Dynamics, Volume 55, 2020 – Issue 14

ABSTRACT:

Abstract

Medicinal herbs have proved along history to be a source of multiple cures. In this paper, we demonstrate how hydroxychloroquine can act as a good inhibitor of SARS-CoV-2 Spike protein receptor-binding-domain using molecular docking studies. We also unveil how hydroxychloroquine can interfere in the prevention of Lys353 in hACE2 from interacting with the corresponding binding hotspot present on the Spike protein. Further screening of artemisinin & derived compounds produced better Vina docking score than hydroxychloroquine (-7.1 kcal mol−1 for artelinic acid vs. −5.5 kcal mol−1 for hydroxychloroquine). Artesunate, artemisinin and artenimol, showed two mode of interactions with Lys353 and Lys31 binding hotspots of the Spike protein. Molecular dynamics analysis confirmed that the formed complexes are able to interact and remain stable in the active site of their respective targets. Given that these molecules are effective antivirals with excellent safety track records in humans against various ailment, we recommend their potential repurposing for the treatment of SARS-CoV-2 patients after successful clinical studies. In addition, an extraction protocol for artemisinin from Artemisia annua L. is proposed in order to cope with the potential urgent global demand.

KEYWORDS: