Search results for "GREEN"

Ligand Effect on Iron-Catalyzed Cross-Coupling Reactions: Evaluation of Amides as O-Coordinating Ligands

2019

The development of new highly efficient O‐coordinating ligands for iron‐catalyzed C(sp2)−C(sp3) cross‐coupling reactions is reported. A structure‐reactivity study on the effect of amides as ligands in the industrially‐important iron‐catalyzed cross‐coupling of aryl chlorides with challenging organometallics possessing β‐hydrogens was performed. Investigation of a series of new 21 ligands that rationally vary in O‐coordination aptitude as well as sterics around the amide bond pinpointed the features that are important for catalysis. The study led to the discovery of several highly efficient ligands for cross‐coupling, including TMU (TMU=tetramethylurea), N‐cyclic and coordinating benzamides.…

Improved Biocatalytic Activity of theDebaryomycesSpecies in Seawater

2019

Influence of Adsorbed Water on the Activation Energy of Model Photocatalytic Reactions

2017

Two commercial (Merck and Sigma-Aldrich) and two home prepared (HP05 and HP05C) powdered TiO2 photocatalysts were investigated by fast field cycling nuclear magnetic resonance experiments in order to explore the nature of the interactions between water and the solid surfaces. The results were related to the activation energies determined at temperatures ranging from 303 to 353 K for the photocatalytic oxidation in water of three model molecules presenting different interactions with the solid surface (catechol, phenol, and metylbenzoate). The photoactivity results at different temperatures were comparable to each other because the runs were carried out while keeping constant the concentrati…

Green synthesis of bromine by TiO2 heterogeneous photocatalysis and/or ozone: A kinetic study

2018

Abstract Elemental bromine is an industrially relevant compound traditionally produced from bromide ions by using chlorine as the oxidizing agent. Problems related to transportation and handling of the corrosive, expensive and toxic chlorine make green synthetic alternatives highly desirable. In this paper the green synthesis of bromine from bromide in aqueous solutions under mild conditions by means of TiO2 photocatalysis and/or ozonation has been investigated from a kinetic point of view. The ozonation in the absence of the photocatalyst follows a first order kinetic with respect to both ozone and bromide. The kinetics of the reactions in the presence of the photocatalyst has been describ…

Comparison of green sample preparation techniques in the analysis of pyrethrins and pyrethroids in baby food by liquid chromatography–tandem mass spe…

2017

A new selective and sensitive liquid chromatography triple quadrupole mass spectrometry method was developed for simultaneous analysis of natural pyrethrins and synthetic pyrethroids residues in baby food. In this study, two sample preparation methods based on ultrasound-assisted dispersive liquid–liquid microextraction (UA-DLLME) and salting-out assisted liquid–liquid extraction (SALLE) were optimized, and then, compared regarding the performance criteria. Appropriate linearity in solvent and matrix-based calibrations, and suitable recoveries (75–120%) and precision (RSD values ≤ 16%) were achieved for selected analytes by any of the sample preparation procedures. Both methods provided the…

Essential oils from three Algerian medicinal plants (Artemisia campestris, Pulicaria arabica, and Saccocalyx satureioides) as new botanical insectici…

2020

Medicinal and aromatic plants represent an outstanding source of green active ingredients for a broad range of real-world applications. In the present study, we investigated the insecticidal potential of the essential oils obtained from three medicinal and aromatic plants of economic importance in Algeria, Artemisia campestris, Pulicaria arabica, and Saccocalyx satureioides. Gas chromatography coupled with mass spectrometry (GC-MS) was used to study the essential oil chemical compositions. The three essential oils were tested against a mosquito vectoring filariasis and arboviruses, i.e., Culex quinquefasciatus, a fly pest acting also as pathogens vector, Musca domestica, and an agricultural…

Silica Nanoparticles for Insect Pest Control.

2019

To date, control strategies used against insect pest species are based on synthetic insecticide applications. In addition, the efficacy of these treatments could be decreased due to insecticide resistance in insect populations. Also, the irrational use of chemical control strategies has negative consequences of non-target organisms and threatening human health. Designing nanomaterial for pest insect control is a promising alternative to traditional insecticide formulations. In particular, it has been proven that silica nanoparticles have the potential for molecules delivery, release control improvement and also their toxicity as insecticide alone. In this work, we summarized the state of kn…

Carlina acaulis and Trachyspermum ammi essential oils formulated in protein baits are highly toxic and reduce aggressiveness in the medfly, Ceratitis…

2021

Abstract Essential oil (EO)-based botanical insecticides are considered a promising option for Integrated Pest Management (IPM). However, the sublethal effects of EO-based insecticides are understudied. No information is available on the potential effects of EO exposure on insect aggressive traits. In this study, the toxicity of two EOs with documented efficacy on insect vectors and agricultural pests, and which were obtained from the roots of silver thistle (Carlina acaulis L., Asteraceae) and seeds (i.e. schizocarps) of ajwain (Trachyspermum ammi (L.) Sprague, Apiaceae), was evaluated against adults of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (medfly), a cosmopolitan fr…

Vers une tridimensionalité du contrôle interactif

2011

We propose in this paper to revisit the concept of interactive control, highlighted by Robert Simons, examining the use of "environmental control systems" in Ten French Companies proactive in ecology. By showing that interactivity of "control systems" is not limited to a vertical dimension as suggested by Simons, but it tends towards three-dimensional (vertical, transversal and external), this study highlights the interest of explore further upstream the concept of interactive control little studied in the literature.

Apparent interfacial shear strength of short-flax-fiber/starch acetate composites

2016

Abstract The paper deals with an indirect industry-friendly method for identification of the interfacial shear strength (IFSS) in a fully bio-based composite. The IFSS of flax fiber/starch acetate is evaluated by a modified Bowyer and Bader method based on an analysis of the stress–strain curve of a short-fiber-reinforced composite in tension. A shear lag model is developed for the tensile stress–strain response of short-fiber-reinforced composites allowing for an elastic-perfectly plastic stress transfer. Composites with different fiber volume fractions and a variable content of plasticizer have been analyzed. The apparent IFSS of flax/starch acetate is within the range of 5.5–20.5 MPa, de…