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From Pine to Perfume
Get PDFCST (Crude Sulfated Turpentine) is an upcycled, biomass raw material derived from pinewood; obtained as a waste product of the Kraft process from the pulp and paper industry. The current report provides an overview of the major perfumery ingredients obtained from CST-derived alpha- and beta-pinene to-date and part of the Firmenich manufacturing portfolio, post DRT acquisition
Towards Net Zero Greenhouse Gas Emissions in the Energy and Chemical Sectors in Switzerland and Beyond - A Review
Get PDFIn today’s societies, climate-damaging and finite fossil resources such as oil and natural gas serve a dual purpose as energy source and as carbon source for chemicals and plastics. To respond to the finite availability and to meet international climate goals, a change to a renewable energy and raw material basis is inevitable and represents a highly complex task. In this review, we assess possible technology paths for Switzerland to reach these goals. First, we provide an overview of Switzerland’s current energy demand and discuss possible renewable technologies as well as proposed scenarios to defossilize the current energy system. In here, electric vehicles and heat pumps are key technologies, whereas photovoltaics replace nuclear power to deliver clean electricity. The production of chemicals also consumes fossil resources and for Switzerland, the oil demand for imported domestically used chemicals and plastics corresponds to around 20 % of the current energetic oil demand. Thus, we additionally summarize technologies and visions for a sustainable chemical sector based on the renewable carbon sources biomass, CO2 and recycled plastic. As biomass is the most versatile renewable energy and carbon source though with a limited availability, aspects and proposed strategies for an optimal use are discussed
What Goes in Must Come out: The Story of Uric Acid: Chemical Education
No full textBirds and reptiles convert waste ammonia into uric acid, while mammals excrete urea, with only small amounts of uric acid ending up in urine. This column explores the varying roles of uric acid and important calcium and sodium salts, and introduces pi-stacking interactions in solid-state structures
SCS Academy | Achieving Gender Equality and Diversity in the Natural Sciences | Chimia Report
No full textCrop Protection Chemistry: Innovation with Purpose: Perspectives on Chemistry and Society on the Occasion of the 75th Anniversary of CHIMIA
No full textTowards the Directed Evolution of Artificial Metalloenzymes
Get PDFArtificial metalloenzymes (ArMs) are a class of enzymes holding great promise. In contrast to natural enzymes, the core of ArMs is a synthetic metallocofactor, with potential for bio-orthogonal reactivity, incorporated within a host protein. Next to chemical optimization of the metallocofactor,
genetic optimization of the protein allows the further improvement of the ArM. Genetic optimization through directed evolution requires extensive screening of a large sequence-scape to enable the optimization of a desired phenotype. The process is however mostly limited by the throughput of
the tools and methods available for screening. In recent years, versatile methods based on droplet microfluidics have been developed to address the need for higher throughput. This article aims to give an introduction into ArMs and the recent technological developments allowing high-throughput
directed evolution of enzymes
Listening with Curiosity – Tracking the Acoustic Response of Portable Laser Ablation
Get PDFNowadays, one of the methods of choice for minimal invasive sampling of solid matter is laser ablation (LA). Routine LA sampling is performed commonly in the laboratory and the amount of ablated mass can directly be monitored and analysed. By contrast laser-based sampling in the field,
using a portable laser ablation system (pLA), still remains challenging concerning low-absorbing or NIR-transparent samples. The current hardware is limited in regards to photon energy and density resulting in unsteady ablation. But as the actual amount of collected mass is the major crux
of on-site sampling, with this performance it is often unknown and estimates can only be made based on the experience from prior method development and the experience of the user. In the following work an easy-to-use method to monitor the amount of ablated material collected during laser-based
sampling by measuring the acoustic response is presented. The pLA-system was coupled to inductively coupled plasma mass spectrometry (ICPMS) via a diffusion driven gas exchange device (GED) which allowed to monitor mass removal and acoustic response quasi-simultaneously. For the current
instrumentation only actual mass removal leads to the formation of shockwaves (SW) and, thus, acoustic signals. These events can be used as indicator for executed LA events and counted on an individual basis. The intensity of acoustic signals has been shown to correlate with the LA mass, i.e.,
the amount of ablated material. This allows to perform re-adjustment of the laser focus during sampling for optimal ablation based on the intensity of the acoustic signal. Likewise, acoustic intensity together with counting allows the operator to make estimates about total mass sampled. Therefore,
unsuccessful laser aerosol collection in the field shall become a thing of the past
Iron-Catalysed Remote C(sp3)-H Azidation of O-Acyl Oximes and N -Acyloxy Imidates
Get PDFThe azido group occupies an important position in modern organic chemistry, broadly used as amine surrogates and as anchors in bioconjugation. Despite their importance, examples of selective direct azidation of inert C(sp3)–H bonds remain limited and often require strong
oxidative conditions. Herein, we highlight the use of O-acyl oximes and N-acyloxy imidates as directing groups for the selective iron-catalysed azidation of C(sp3)–H bond with trimethylsilyl azide, giving access to various ?-azido ketones and ?-azido
alcohols in moderate to excellent yields. The iron catalyst is assumed to play a dual role in these catalytic processes: as a reductant to generate the reactive iminyl and imidate radicals, respectively, and as a redox centre to mediate the azido transfer to the translocated carbon radical