Chemists at Ruhr-Universität Bochum have tested a new approach for activating chemical reactions based on the element selenium. They demonstrated that selenium can form bonds similar to those of hydrogen bonds, resulting in accelerated reactions. The exact mechanism is described by the team at the Chair of Organic Chemistry 1 in Bochum, including Prof Dr Stefan Huber and Patrick Wonner, in the journal “Angewandte Chemie”, in collaboration with Prof Dr Daniel Werz from Braunschweig University of Technology.

Traditionally, metal complexes are used as activators and catalysts. They form complete, i.e. covalent bonds with the molecule whose reactions they are supposed to accelerate. However, the metals are often expensive or toxic.

Read more ...

It looks like a real heart. And this is the goal of the first entirely soft artificial heart: to mimic its natural model as closely as possible. The silicone heart has been developed by Nicholas Cohrs, a doctoral student in the group led by Wendelin Stark, Professor of Functional Materials Engineering at ETH Zurich. The reasoning why nature should be used as a model is clear. Currently used blood pumps have many disadvantages: their mechanical parts are susceptible to complications while the patient lacks a physiological pulse, which is assumed to have some consequences for the patient.

Read more ...

Drones, or unmanned aerial vehicles (UAVs), have been around since the early 1900s. Originally used for military operations, they became more widely used after about 2010 when electronic technology got smaller, cheaper and more efficient, prices on cameras and sensors dropped, and battery power improved. Where once scientists could only observe earth from above by using manned aircraft or satellites, today they are expanding, developing and refining their research thanks to drones.

Read more ...

Over the next four months, NOAA scientists will launch unmanned ocean vehicles, called Saildrones, from the Arctic to the tropical Pacific Ocean to help better understand how changes in the ocean are affecting weather, climate, fisheries and marine mammals. The wind and solar-powered research vehicles that resemble a sailboat will travel thousands of miles across the ocean, reaching some areas never before surveyed with such specialized technology. 

Read more ...

Rising temperatures due to global warming will make it harder for many aircraft around the world to take off in coming decades, says a new study. During the hottest parts of the day, 10 to 30 percent of fully loaded planes may have to remove some fuel, cargo or passengers, or else wait for cooler hours to fly, the study concludes. The study, which is the first such global analysis, appears today in the journal Climatic Change.

Read more ...

NOAA’s Annual Greenhouse Gas Index, which tracks the warming influence of long-lived greenhouse gases, has increased by 40 percent from 1990 to 2016 -- with most of that attributable to rising carbon dioxide levels, according to NOAA climate scientists.

The role of greenhouse gases on influencing global temperatures is well understood by scientists, but it’s a complicated topic that can be difficult to communicate. In 2006, NOAA scientists introduced the Annual Greenhouse Gas Index as a way to help policymakers, educators and the public understand changes in the direct climate warming influence exerted by greenhouse gas levels over time.

Read more ...

More Articles ...

Subcategories