Molecule matters Dinitrogen

Dinitrogen (N₂) is a very stable and inert molecule due to the formation of a triple bond between the two atoms. Surprisingly isoelectronic molecules are quite reactive making dinitrogen very useful and unique.     

Silicon photonics Silicon Raman lasers

The increased use of optoelectronic devicessuch as TV screens and computer monitors in everyday life, calls for a material on which integration of all circuits may be performed. Silicon, the most widely used material in electronics, has limited application in optoelectronics due to its poor light emission property. In this article, the need for silicon photonics in present day ICs, and communication, the reason for its inefficient light emission, and recent breakthrough in the form of Si Raman laser are discussed.     

Fire synthesis Preparation of alumina products

The novel ‘solution combustion method’ or ‘fire synthesis’ has been used to make high temperature synthesised ceramic materials. The process, which can be initiated at low temperature, is self-propagating and gas-producing. Fine-particle alumina and its related oxides can be easily prepared in bulk by the redox mixture method.     

Mangroves The most fragile forest ecosystem

Mangroves, an exclusive group of plants with remarkable ecological importance, inhabit mostly the zones washed by the back and forth movement of tides. They are disappearing rapidly from their natural habitat due to various reasons. Mangroves create a unique ecological environment that is composed of rich assemblages of species. Economic importance of mangroves is also noteworthy.     

Gravitational-wave astronomy A new window to the Universe

We present a broad overview of the emerging field of gravitational-wave astronomy. Although gravitational waves have not been directly detected yet, the worldwide scientific community is engaged in an exciting search for these elusive waves. Once detected, they will open up a new observational window to the Universe.     

A pizza saga Five delicacies of modern geometry

In this article we introduce the reader to some pretty results concerning a circle and regions within it defined by various line segments. We have framed the results in terms of a pizza, so we could well call this an introduction to Pizza Geometry! The novel aspect is the variety of approaches used to prove these results.     

The Freudenstein equation Design of four-link mechanisms

Ferdinand Freudenstein is widely acknowledged to be the father of modern kinematics of mechanisms and machines. His PhD thesis in 1954 and subsequent research papers by him and his students have influenced academic and industrial research, teaching and practice related to the analysis and design of mechanisms and machines throughout the world. In this article, we revisit Freudenstein’s thesis and the equation named after him. The Freudenstein equation results from an analytical approach towards analysis and design of four-link mechanisms which, along with its variants, are present in a large number of machines used in daily life.     

Irving Langmuir A pioneering industrial physical chemist

This is a biography of one of the most famous industrial chemists of the last century. Irving Langmuir showed that developing new devices leads to fundamental work of the highest order. Langmuir was the first industrial chemist to get the Noble Prize.     

Concept of green chemistry Redesigning organic synthesis

Green chemistry is the utilization of a set of principles that will help reduce the use and generation of hazardous substances during the manufacture and application of chemical products. Green chemistry aims to protect the environment not by cleaning up, but by inventing new chemical processes that do not pollute. It is a rapidly developing and an important area in the chemical sciences. Principles of green chemistry, developments in this field and some industrial applications are discussed.