Search results for "chemical science"
showing 10 items of 9771 documents
Controlling the crystal growth of potassium iodide with a 1,1'-bis(pyridin-4-ylmethyl)-2,2'-biimidazole ligand (L) – formation of a linear [K4I4L4]n …
2018
The crystal growth of potassium iodide was controlled by using the neutral organic 1,1′-bis(pyridin-4-ylmethyl)-2,2′-biimidazole (L) ligand as a modifier. The selected modifier allows the preservation of original cubic [K4I4] units and their arrangement into a linear ligand-supported 1D chain. The supported [K4I4] cubes are only slightly distorted compared to the cubes found in pure KI salt. The N–K binding of the ligand to the KI salt, as well as weak I⋯H, N⋯H, and N⋯I interactions, stabilizes the structure to create a unique 1D polymer of neutral potassium iodide ionic salt inside the [K4I4L4]n complex.
Ces molécules qui éveillent nos papilles
2017
The sense of taste is a chemical sense and one of the most ancestral sensory modalities. It allows detectingand appreciating taste molecules present in our food. Beyond our vital needs, the pleasure elicited from whatwe eat can drive our feeding behaviors sometimes up to excess. Food intake involves several sensorysystems, mainly smell and taste. The underlying molecular mechanisms are relatively complex. This articlefocuses on the extent of the chemical space associated with the five primary tastes (sour, salty, sweet, bitterand umami), and details the fundamental role of gustatory receptors in the perception of taste as well aswithin interindividual variabilities.
Trait Hedonism and the Distribution of Savoring and Positive Emotion States in Everyday Life.
2022
International audience; The present study aimed at (1) identifying the emotion regulation processes that can explain the trait hedonism positive emotions relationship, and (2) determining whether this relationship varies according to which part of the distribution of positive emotions is considered. To this end, the intensity of the positive emotions felt by 84 adult participants, and the intensity of their engagement in savoring, were assessed twice a day over a month period, using an Experience Sampling Method. Participants’ distributions of these variables were then related to their level of trait hedonism, assessed with a common questionnaire. Results suggested that, as expected, the tr…
Influence of a Thiolate Chemical Layer on GaAs (100) Biofunctionalization: An Original Approach Coupling Atomic Force Microscopy and Mass Spectrometr…
2013
International audience; Widely used in microelectronics and optoelectronics; Gallium Arsenide (GaAs) is a III-V crystal with several interesting properties for microsystem and biosensor applications. Among these; its piezoelectric properties and the ability to directly biofunctionalize the bare surface, offer an opportunity to combine a highly sensitive transducer with a specific bio-interface; which are the two essential parts of a biosensor. To optimize the biorecognition part; it is necessary to control protein coverage and the binding affinity of the protein layer on the GaAs surface. In this paper; we investigate the potential of a specific chemical interface composed of thiolate molec…
Entrapment of a linear water pentamer into a uranyl-salophen dimer in the solid state
2019
In the solid state, uranyl-salophen complex 1, decorated with bipyridyl sidearms, self-assembles from moist acetonitrile into dimeric species displaying a confined water pentamer, as observed by X-...
Review article: recommended reading list of early publications on atomic layer deposition - outcome of the "virtual Project on the History of ALD"
2017
Atomic layer deposition (ALD), a gas-phase thin film deposition technique based on repeated, self-terminating gas-solid reactions, has become the method of choice in semiconductor manufacturing and many other technological areas for depositing thin conformal inorganic material layers for various applications. ALD has been discovered and developed independently, at least twice, under different names: atomic layer epitaxy (ALE) and molecular layering. ALE, dating back to 1974 in Finland, has been commonly known as the origin of ALD, while work done since the 1960s in the Soviet Union under the name "molecular layering" (and sometimes other names) has remained much less known. The virtual proj…
Polymeric nanoparticles for siRNA delivery: Production and applications
2017
Gene therapy through the use of siRNA and a polymeric carrier are becoming an efficient therapeutic option to conventional pharmaceutical formulations for the treatment of deadly diseases, such as cancer, pulmonary, ocular and neurodegenerative diseases. However, several considerations regarding the stability, formulation, and efficacy have to be faced up until these systems could be considered to be a marketable pharmaceutical products for to extend siRNA application to clinical practice. This review is focused on the key challenges of siRNA therapeutics, with special attention on the faced obstacles and on the formulation-related difficulties, providing a list of requirements needed for o…
Development of New Targeted Inulin Complex Nanoaggregates for siRNA Delivery in Antitumor Therapy.
2021
Here, a novel strategy of formulating efficient polymeric carriers based on the already described INU-IMI-DETA for gene material whose structural, functional, and biological properties can be modulated and improved was successfully investigated. In particular, two novel derivatives of INU-IMI-DETA graft copolymer were synthesized by chemical functionalisation with epidermal growth factor (EGF) or polyethylenglycol (PEG), named INU-IMI-DETA-EGF and INU-IMI-DETA-PEG, respectively, in order to improve the performance of already described “inulin complex nanoaggregates” (ICONs). The latter were thus prepared by appropriately mixing the two copolymers, by varying each component from 0 to 100 wt%…
Design and Characterization of Effective Ag, Pt and AgPt Nanoparticles to H2O2 Electrosensing from Scrapped Printed Electrodes
2019
The use of disposable screen-printed electrodes (SPEs) has extraordinarily grown in the last years. In this paper, conductive inks from scrapped SPEs were removed by acid leaching, providing high value feedstocks suitable for the electrochemical deposition of Ag, Pt and Ag core-Pt shell-like bimetallic (AgPt) nanoparticles, onto screen-printed carbon electrodes (ML@SPCEs, M = Ag, Pt or AgPt, L = metal nanoparticles from leaching solutions). ML@SPCEs were characterized by scanning electron microscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The results were compared to those obtained when metal nanoparticles were synthesised using standard solutions of metal salts (MS@…
Synthesis and characterization of Zwitterionic Zn(II) and Cu(II) coordination compounds with ring-substituted 2,2′-biimidazole derivatives
2016
Zwitterionic coordination compounds with strongly asymmetrical charge distribution were synthesized and characterized. Ring-substituted biimidazoles were used as the primary ligands for Zn and Cu compounds. Formation of Zwitterionic coordination compound was found to be strongly dependent on the pH of the reaction medium as well as on the ring and nitrogen substituents of the ligand. Reaction of the Df-R2biim (Df-R2biim = 2,2′-bi-1R-imidazole-5,5′-dicarboxaldehyde, R = Me, Et or Pr) with ZnCl2 in neutral conditions led to binuclear compounds [Zn2Cl4(Df-R2biim)2] with two bridging ligands (1a–c). Reaction with CuCl2·2H2O gave neutral mononuclear compound [CuCl2(Df-Me2biim)] (1d) with chelati…