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Topic Review
Ig Nobel Prize
The Ig Nobel Prize is a satirical yet legitimate annual award presented by the Annals of Improbable Research to honor scientific achievements that are unusual, imaginative, and thought-provoking. Established in 1991, the prize celebrates research that "first makes people laugh, and then makes them think," highlighting the intersection of humor and scientific inquiry. While often humorous in subject matter, winning studies are typically grounded in peer-reviewed research and aim to promote public engagement with science through curiosity, creativity, and accessibility.
  • 15
  • 20 May 2025
Topic Review
Galium verum Extract—An Unexpected Versatility of Plant Chemistry
Corrosion inhibitors are substances that reduce or eliminate the corrosion of a metal in a certain environment. Corrosion inhibitors act by several mechanisms, including adsorption, film formation, passivation, and oxygen scavenging. Due to their toxicity, classic corrosion inhibitors affect the environment. Therefore, in recent years, more and more studies have focused on the development of eco-friendly inhibitors for the environment. In this study, ethanolic extract of Galium verum (GV) was tested for the inhibition of steel corrosion in 1 M HCl medium using electrochemical methods: open circuit potential (OCP), potentiodynamic polarization (PP), and electrochemical impedance spectroscopy (EIS). Reverse-phase liquid chromatography (HPLC) and gas chromatography mass spectrometry (MS-GC) previous studies state that GV extract contains polyphenols and other chemical species responsible for the inhibitory effect. Corrosion investigations have highlighted the influence of the concentration of the GV extract, in the range of 50 ÷ 400 ppm G.A.E./mL, as well as the influence of temperature in the range of 20 ÷ 50 °C. The corrosion inhibitory efficiency of the Galium verum ethanolic extract had a maximum value of 91.82% for a concentration of 400 ppm polyphenol content, demonstrating the inhibitory potential of this green product in an acidic environment for mild steel. Statistical calculus on the obtained values of EIS inhibitor efficiency showed that the effect of the extract becomes stronger at higher concentrations.
  • 95
  • 12 May 2025
Topic Review
Phosphopolyoxometalates (Mo, W, V)  corrosion Inhibitors for Steels
Nowadays, choosing a corrosion inhibitor is not only based on efficiency, but must also consider the toxicity of the compound, the impact on the environment, and, obviously, the regulations in the field. In the last two decades, a special class of substances has begun to be studied, namely polyoxometalates (POMs). Their electronic properties and redox characteristics make the polyoxometalates potential candidates to be used in many electrochemical processes, and as potential corrosion inhibitors. Electrochemical methods such as a Tafel extrapolation plot, chronopotentiometry, or gravimetry have been used to establish the capacity of corrosion inhibition of S235 and SS304 steels in the presence of phosphovanadomolibdate acid (@PMoV) and phosphovanadotungstate acid (@PWV) in 0.5 M sulphuric acid solution. The inhibition efficiency for S235 steel is about 90.6% for @PMoV, and 69.5% for @PWV after 24 h of immersion. In the case of SS304 steel, polyoxometalates have similar effects: the inhibition degree, as a function of Flade potential, is 4.66 for @PMoV; better than 3.26 for @PWV, with both proving the passivant effect.
  • 101
  • 12 May 2025
Topic Review Peer Reviewed
Fermentative Butanol Production—Perspectives and Scale-Up Challenges
Sustainable solutions to the use of petrochemical products have been increasingly sought after in recent years. While alternatives such as biofuels have been extensively explored and commercialized, major challenges remain in using heterogeneous feedstocks and scaling-up processes. Among biofuels, higher alcohols have recently gained renewed interest, especially in the context of upcycling agri-food residues and other industrial organic wastes. One of the higher alcohols produced via fermentation is butanol, which was developed over a century ago. However, the commercial production of butanol is still not widespread, although diverse feedstocks are readily available. Hydrolysis of the feedstocks and scale-up challenges in the fermentation and purification of butanol are recurring bottlenecks. This review addresses the current state of fermentative butanol production and opportunities to address scale-up challenges, including purification. With the significant interest and promise of precision fermentation, this review also addresses some of the recent advances and potential for enhanced fermentative butanol production.
  • 63
  • 14 Apr 2025
Topic Review Peer Reviewed
The Logarithmic Derivative in Scientific Data Analysis
The logarithmic derivative has been shown to be a useful tool for data analysis in applied sciences because of either simplifying mathematical procedures or enabling an improved understanding and visualization of structural relationships and dynamic processes. In particular, spatial and temporal variations in signal amplitudes can be described independently of their sign by one and the same compact quantity, the inverse logarithmic derivative. In the special case of a single exponential decay function, this quantity becomes directly identical to the decay time constant. When generalized, the logarithmic derivative enables local gradients of system parameters to be flexibly described by using exponential behavior as a meaningful reference. It can be applied to complex maps of data containing multiple superimposed and alternating ramping or decay functions. Selected examples of experimental and simulated data from time-resolved plasma spectroscopy, multiphoton excitation, and spectroscopy are analyzed in detail, together with reminiscences of early activities in the field. The results demonstrate the capability of the approach to extract specific information on physical processes. Further emerging applications are addressed.
  • 126
  • 14 Apr 2025
Topic Review
ApDOS (Aminocatalytic Privileged Diversity-Oriented Synthesis)
ApDOS (Aminocatalytic privileged Diversity-Oriented Synthesis) is a synthetic strategy that integrates the principles of aminocatalysis and diversity-oriented synthesis (DOS) to access structurally diverse libraries of privileged molecular scaffolds. Privileged structures—defined as frameworks capable of high-affinity binding to multiple biological targets—are key motifs in medicinal chemistry and chemical biology. ApDOS utilizes various aminocatalytic activation modes, including enamine, iminium ion, dienamine, trienamine, tetraenamine, and vinylogous iminium ion catalysis, to transform simple and readily available building blocks such as aldehydes and ketones into stereochemically rich and functionally elaborate architectures. The conceptual framework of ApDOS builds on the modularity and reactivity of aminocatalytic intermediates to populate biologically relevant regions of chemical space. By enabling mono- and multicomponent reactions—including cascade and domino sequences—ApDOS expands the synthetic utility of aminocatalysis beyond conventional target-oriented strategies. This methodology has proven particularly effective for the construction of spirocyclic, fused, bridged, and polycyclic scaffolds, often in a highly enantioselective and atom-economical manner. ApDOS represents a general platform for exploring molecular diversity via catalytic reactivity modes and offers significant potential for drug discovery and chemical probe development.
  • 250
  • 09 Apr 2025
Biography
David W.C. MacMillan
David W.C. MacMillan is a Scottish-born American chemist renowned for his pioneering work in the field of asymmetric organocatalysis. Born in Bellshill, Scotland, in 1968, MacMillan earned his undergraduate degree from the University of Glasgow and completed his Ph.D. under Professor Larry Overman at the University of California, Irvine.[1] He began his independent academic career at the Univers
  • 315
  • 07 Apr 2025
Biography
Benjamin List
Benjamin List is a German chemist internationally recognized for pioneering the field of asymmetric organocatalysis.[1] Born in Frankfurt in 1968, he obtained his Ph.D. in chemistry from Goethe University Frankfurt under Johann Mulzer. Following postdoctoral research with Richard Lerner and Carlos F. Barbas III at The Scripps Research Institute, he joined the Max-Planck-Institut für Kohlenforsc
  • 246
  • 07 Apr 2025
Topic Review
Asymmetric Organocatalysis
Asymmetric organocatalysis is a branch of catalysis that employs small organic molecules to promote enantioselective chemical reactions. This field has grown rapidly since the early 2000s, offering a metal-free, environmentally benign approach to asymmetric synthesis. Organocatalysis complements enzymatic and metal-based catalysis by enabling precise stereochemical control using simple, accessible catalysts. Its applications span natural product synthesis, medicinal chemistry, and sustainable chemical manufacturing.
  • 294
  • 07 Apr 2025
Topic Review
Chiral Hydroxamic Acid Ligands in Asymmetric Synthesis
Chiral hydroxamic acid (HA) and bis-hydroxamic acid (BHA) ligands have emerged as powerful platforms for enantioselective catalysis, especially in asymmetric epoxidation and natural product synthesis. Recent advances in ligand architecture—such as phenyl-centric C₂-symmetric scaffolds—have enabled enhanced stereocontrol, broader substrate scope, and compatibility with diverse metal catalysts like Ti(IV) and V(V). These ligands not only facilitate epoxide formation with exceptional enantiomeric excess but have also proven essential in the total synthesis of complex bioactive compounds, including florfenicol, ophiodilactones, and α-bisabolol. This entry offers a detailed perspective on the evolution, application, and future prospects of chiral HA/BHA ligands in organic synthesis.
  • 437
  • 04 Apr 2025
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