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International audience; An innovative photoreactor was applied as an emerging advanced oxidation process (AOP) to investigate Paracetamol (PL) degradation under different operating conditions. The system consisted of a textile woven from optical fiber and textile yarn. The luminous fiber textile was coupled to UVA LED, and the photocatalytic textile fibers is impregnated with TiO2. The effectiveness of configuration I, based on a luminous textile with UV LED, was compared with that based of TiO2 immobilized on cellulosic paper (CP) with external UV irradiation (configuration 2). The specific degradation rate obtained with configuration 1 was 40 times higher than that with configuration II. Configuration I also showed efficient performance in mineralization per Watt consumed, with values reaching 81 times higher than those obtained with configuration II. Also, to achieve high removal effi-ciency of the pollutant with the new technology of luminous textiles, the effect of operating parameters, namely pollutant concentration, UV intensity, flow rate and TiO2 mass deposited were discussed. It is worth noting that the optimal conditions for a 95.7 % degradation rate of 1 mg/L of Paracetamol were obtained with 26 g/m2 mass catalyst, 5 W/m2 UV intensity and 52.2 L/h flow rate after 340 min. In addition, upon associating two luminous textiles, the degradation efficiency reached 98.76 % after only 140 min. Besides, by adding hydrogen peroxide (H2O2) in the optimal conditions with 10 mg/L of Paracetamol concentration, the degradation efficiency reached 98.81 % after 240 min. The excellent performances in terms of degradation rate, mineralization per Watt consumed, and energy consumption make luminous textiles an attractive alternative to conventional photo-catalytic reactors designed for the removal of Paracetamol in water and wastewater.

This paper mainly deals with the isovaleraldehyde degradation with the help of a nonthermal plasma surface discharge (NPSD) coupled with photocatalysis. The efficiency of NPSD reactor, for gas treatment, was studied for different binary mixtures: (1) mixture of aldehydes (Isovaleraldehyde and Butyraldehyde) and (2) mixture of aldehyde and amine (Isovaleraldehyde and Trimethylamine). A planar continuous reactor is used to investigate the effect of addition of another pollutant on the performance of oxidation process. A synergetic effect was observed by combining NPSD and photocatalysis for the degradation of mixture of pollutants. In addition, combined NPSD/photocatalysis has significantly enhanced the CO2 selectivity, as compared to NPSD alone. This is attributed to the formation of more reactive species due to the presence of TiO2 in the plasma discharge zone. Moreover, ozone and UV light on TiO2, produced by plasma, have activated the surface leading to enhanced mineralization. In addition, the byproducts of each binary mixture were identified and evaluated.

Weed seedbank was assessed and an integrated weed management package was developed to control Parthenium hysterophorus in vegetable capsicum. Field experiments were conducted simultaneously in a Parthenium-site (PS) and Parthenium-free site (PFS) during two consecutive seasons in a split-plot design replicated three times. Primary tillage (ploughing and manual weeding) were the main plots and sub-plots consisted of post-tillage practices; (a) Oxyfluorfen applied two-days before transplanting the crop (180 g a.i. ha−1), (b) gliricidia leaf mulch applied soon after transplanting (6 t ha−1, 68% moisture), and (c) control. After transplanting, all weeds in PS, except P. hysterophorus, were removed manually in all plots bi-weekly, while weeds were not controlled in PFS. Parthenium hysterophorus in PS and Cyperus rotundus in PFS dominated the soil seedbank in upper 0–5 cm. Soil seedbank of P. hysterophorus in PS was higher in season-1 (March–August) than in season-2 (September–February) and viable even when buried 15 cm deep. Interaction between primary and post-tillage practices was not significant (P > .05) on plant height, canopy width, and yield of the crop. Capsicum yield in PFS was 40% higher in season-1 and 9.5% higher in season-2 compared to those of PS, due to lower weed competition and higher crop growth in the former. Manual weeding or ploughing as primary tillage followed by mulching with gliricidia leaves as a post-tillage practice suppressed P. hysterophorus effectively and enhanced growth and yield of vegetable capsicum.

A series of titania-carbon nanotubes (TiO2-CNTs) supported MnOx-CuO catalysts were prepared and investigated for NH3-SCR of NO at low temperature. It was observed that the addition of Cu and/or CNTs to Mn/TiO2 has a beneficial effect in improving the activity of the catalyst. In addition, the effect of Cu loading was also studied and found that the catalyst with 5 wt% Cu (Mn-Cu5/Ti-CNTs) exhibited the best NH3-SCR performance. Remarkably, the Mn-Cu5/Ti-CNTs showed excellent resistance to SO2/H2O in comparison to the Mn/TiO2 catalyst. The addition of CNTs has increased the specific surface area, total pore volume, and reduced the average pore size of the catalyst. Meanwhile, the Cu loading has enhanced the Mn4+ species and chemisorbed oxygen species on the surface of the catalyst. Besides, the incorporation of both Cu and CNTs have decreased the catalyst reduction temperature and increased the amount and strength of acidic sites on the catalyst. All these factors contributed to the superior NH3-SCR activity and SO2/H2O resistance of the catalyst.

GABA is produced from the decarboxylation of glutamate by glutamate decarboxylase enzyme (GadB). Various hetrologous GadB enzymes has been indentified and introduced in Escherichia coli to improve the productivity of GABA. In this study, cell surface display strategy was employed by displaying Neurospora crassa glutamate decarboxylase (GadB) on the surface of Escherichia coli using OmpC as an anchoring motif. To construct the display system, the GadB was fused to truncated C-terminus of OmpC and expressed in E. coli. The recombinant E. coli displaying GadB has produced 3.03 g/L of GABA from 10 g/L glutamate within 12 h of culture period. When the GadB display system was cultured at high cell density, 100% GABA yeild was achieved from 50 g/L of glutamate. The results suggest that the GadB expression on the E. coli surface is stable and effective on GABA production. The surface display strategy can be applied on other potential enzyme candidates and used in Industry for bulk chemical production.

Gamma-aminobutyric acid (GABA) is a precursor to pyrrolidone, a monomer used for the production of a biodegradable polymer known as nylon-4. GABA is also widely used in the medical industry to treat conditions such as high blood pressure, anxiety and depression. Generally, GABA is produced from glutamate by the enzyme glutamate decarboxylase (GadB). In this study, a synthetic scaffold complex was introduced between Pyrococcus horikoshii GadB and the GABA antiporter (GadC) from E. coli. P. horikoshii GadB was attached to the N-terminus, C-terminus and middle of E. coli GadC via scaffolding. Among the three scaffold complexes evaluated, the N-terminus scaffold model produced 5.93 g/L of GABA from 10 g/L monosodium glutamate (MSG). When the gabT mutant E. coli XBT strain was used, the highest GABA concentration of 5.96 g/L was obtained, which is 97.8% of GABA yield. In addition to GABA concentration, GABA productivity was increased 3.5 fold via the synthetic scaffold complex.

Over the last 30 years, several experimental chambers were developed and implemented for indoor air studies. Yet, they were not all representative of real indoor air conditions. Either they did not have sufficient volumes or they were hindered by difficulties to control experimental conditions and air exchange rates. In this context, a 40 m 3 Innovative experimental Room for Indoor Air studies (IRINA) has been developed and validated at Mines Douai (Atmospheric Sciences et Environmental Engineering department (SAGE)) to overcome these drawbacks and above all to perform reproducible indoor air studies avoiding any possible experimental biases. IRINA inner walls are covered with aluminum foils. The room is operated in a closed mode and is equipped with a VOC injection system that relies on the heated and pressurized injection of vaporized VOC. IRINA is also equipped with analytical instruments that allow the analysis of both gas (online and offline measurements) and particle phases. IRINA validation evidenced that: (i) the air exchange rate of the room is well controlled over an one year timespan; (ii) both gaseous and particulate background levels in IRINA remain lower than typical indoor air conditions; (iii) fast homogenization of injected VOC concentrations is reached in the room; (iv) adsorption phenomena on IRINA walls are limited; and (v) there is no VOC matrix impact regarding individual VOC decays. The modelling of VOC natural decay in IRINA based on the new INCA-Indoor model showed that the VOC removal in IRINA is mainly due to the air exchange rate.

Environmental regulation on air quality requires the development of energetic efficient volatile organic compounds (VOCs) abatement techniques. Adsorption, photocatalysis, non-thermal plasma and their combinations have been widely studied for VOC treatment. Even if the plasma – material (sorbent or catalyst) association appears as one of the most efficient configuration for VOC removal, it mainly consists in operating continuously the discharge on the material surface as long as the effluent flows across the reactor. This work aims at investigating another approach of plasma – material association for VOC removal: in a first step, the material is used as a sorbent until the complete coverage of adsorption sites; in a second step, once VOC saturation is achieved, the discharge is ignited on the material surface. During both steps, the influence of air relative humidity (RH) is investigated in order to evaluate its impact on the process. The objectives of our approach are: (i) the reduction of energy consumption; (ii) the increase of sorbent life-times by efficient regeneration; (iii) the investigation of plasma interaction with VOC saturated materials; (iv) the investigation of air RH influence on such VOC treatment process. A packed bed reactor coated with TiO 2 has been designed. IPA is used as a model VOC. First, injected power in the packed-bed reactor is characterized as a function of air RH. Complete coverage of TiO 2 surface over 35% RH is suggested as a significant parameter. Then, adsorption of IPA on TiO 2 was monitored until IPA breakthrough. The amount of IPA adsorbed per TiO 2 surface unit is compared to values reported by other authors. The influence of air RH on reversibly and irreversibly adsorbed IPA fractions is investigated. Over 35% RH irreversible adsorption is favored, adsorption modes are discussed. Plasma regeneration of IPA saturated TiO 2 surface leads simultaneously to IPA desorption and mineralization. Increasing air RH favors IPA mineralization and diminishes acetone production. Carbon balance obtained after 1 h plasma treatment reaches 91% in the presence of 50% RH. A thermal treatment is performed after each plasma treatment in order to evidence plasma insensitive adsorbed species and to restore TiO 2 initial surface state. 97% of the carbon balance is collected under 50% RH after thermal treatment. During the thermal step, acetone and CO 2 are mainly produced, their formation pathways are discussed.

Oxidative decomposition of a model volatile organic compound (isopropanol, IP) has been carried out in a catalytic dielectric barrier discharge (DBD) reactor, where modified sintered metal fiber (SMF) filter was used as the inner electrode. The SMF was modified with Mn and Co oxides by impregnation, followed by calcination and the performance of the DBD reactor was tested for the oxidation of IP in the specific input energy range 160–720 J/l by varying the high voltage and frequency. It has been observed that SMF modification by MnO x and CoO x not only improved the conversion of isopropanol, but also increased the selectivity towards total oxidation. MnO x modification showed better performance than CoO x , which may be attributed to the formation of atomic oxygen by in situ decomposition of ozone. It has been demonstrated that with MnO x /SMF it is possible to completely oxidize 100 ppm of isopropanol at SIE