Green extraction of chitin from hard spider crab shells.

A green protocol to extract chitin from crab shells using water soluble ionic liquids (ILs) is here reported. Compared to conventional multistep acid-base extraction methods, this one-pot procedure achieves pulping of recalcitrant crustacean waste shells by employing ammonium acetate, ammonium formate and hydroxylammonium acetate as water-soluble, low-cost and easy to prepare ILs. An extensive parametric analysis of the pulping process has been carried out with different ILs, different ratios, temperature and time.

Upcycling of Chitin to Cross-Coupling Catalysts: Tailored Supports and Opportunities in Mechanochemistry.

In this study chitin derived from shrimp shells was used in the design of heterogeneous Pd-based catalysts for Heck and Suzuki-Miyaura cross-coupling reactions. The synthesis of Pd nanoparticles supported on N-doped carbons was performed through different approaches, including a sustainable mechanochemical approach, by using a twin-screw extruder. All catalytic systems were characterized by a multitechnique approach and the effect of nanoparticles size, N-doping on the support, and their synergistic interactions were elucidated.

Selective Multiphase-Assisted Oxidation of Bio-Sourced Primary Alcohols over Ru- and Mo- Carbon Supported Catalysts.

The oxidation of representative bio-based benzyl-type alcohols has been successfully carried out in a multiphase (MP) system comprised of three mutually immiscible liquid components as water, isooctane, and a hydrophobic ionic liquid as methyltrioctylammonium chloride ([CH(CH)CH]N(Cl)CH), a heterogeneous catalyst (either ad-hoc synthesized carbon-supported Mo or a commercial 5 % Ru/C), and air as an oxidant. The MP-reaction proceeded as an interfacial process with Mo/C or Ru/C perfectly segregated in the ionic liquid phase and the reactant(s)/products(s) dissolved in the aqueous solution. This environment proved excellent to convert quantitatively benzyl alcohols into the corresponding aldehydes with a selectivity up to 99 %, without overoxidation to carboxylic acids.

A Comparative Study to Evaluate the Efficacy of Topical and Infiltrative Anesthesia for Dermatosurgery Through a Subject-Oriented Approach.

Introduction The skin, along with its subcutaneous tissue, constitutes one of the major organ systems of the human body. Dermatosurgery is the branch dealing with skin conditions that operate at the level of skin, without disturbing the of the human organ system. Materials and methods A cross-sectional study was undertaken, which included 100 patients comprised of 50 patients in each group.