SPECTRUM

Schwarzite – New Form of Carbon Created

A completely new form of carbon has been created. Dubbed “Schwarzite’, this new form of carbon is negatively curved unlike fullerenes (the 3-D form of

carbon) and graphene (the 2-D form of carbon) which have positive and zero curvature, respectively.

Zeolites, crystalline form of silicon dioxides and more commonly used as water softeners in laundry detergents and to catalytically crack petroleum into gasoline, turned out to be the key component in taking this carbon form from theory into reality. The details of the research have been published in the journal Proceedings of the National Academy of Sciences.

The theoretical development of schwarzites dates back to the 1880s when German physicist Herman Schwarz investigated curved surfaces that resembled soap bubble surfaces. Much later, in the 1990s, when work on carbon cage molecules was in progress, Schwarz’s name became attached to the hypothetical negatively-curved carbon sheets.

Researchers working in South Korea and Japan were investigating Zeolite-Templated Carbons (ZTCs) – crystalline form of silicon dioxide with carbon structure built into them – and checking for any interesting properties. They accidentally created schwarzites although they were unaware of it.

The importance of the work of the scientists was noticed by the University of California, Berkeley, chemists who identified these ZTC materials as schwarzites based on their negative curvature. Berend Smit, an adjunct professor of chemistry and biomolecular engineering at the University of California, Berkeley, along with his team demonstrated that it was possible to create these (ZTC) structures by injecting a vapour containing carbon into zeolites. Once inside, the carbon assembles into a graphene-like sheet that lines the walls of the pores in the zeolite. In doing so, the surface stretches to minimise the area. As schwarzites are topologically minimal surfaces, they tend to acquire negative curvature. The zeolite is then dissolved to produce pure schwarzites.

According to scientists, it would be possible to pack unusually large amounts of electrical charge into schwarzites which would make them better capacitors than conventional ones used today in electronics. Their large interior volume would also allow storage of atoms and molecules, which is also being explored with fullerenes and nanotubes. Moreover, their large surface area, equivalent to the surface areas of the zeolites they are grown in, could make them as versatile as zeolites for catalysing reactions in the petroleum and natural gas industries.

The team found that of the approximately 200 zeolites created to date only 15 can be used as a template to make schwarzites and only three of them have been used to produce schwarzite ZTCs. However, over a million zeolite structures have been predicted. Therefore, there could be many more possible schwarzite carbon structures made using the zeolite-templating method, say the researchers who developed a way to predict which zeolites can be used to make schwarzites and which cannot be so used.

Optimisation of these structures could prove highly beneficial. In the past, discovering new forms of carbon has yielded exciting technological revolutions having great potential applications in the form of fullerenes and graphene-discoveries which were rewarded by Nobel Prizes in Chemistry in 1996 and Physics in 2010, respectively.

Though the application of schwarzites remains to be seen, the scientists speculate that their unique electronic, magnetic and optical properties can make them useful as supercapacitors, battery electrodes and catalysts, and with their large internal spaces ideal for gas storage and separation.

Contributed by Dr. P.K. Mukherjee, 43, Deshbandhu Society, 15, Patparganj, Delhi-110092; Email: pkm_du@rediffmail.com

The three-dimensional cage structure of a schwarzite that was formed inside the pores of a zeolite.

(Graphics by Yongjin Lee and Efrem Braun; Adapted from news.berkeley.edu)

EXPERIMENTING with extremely tiny materials – a millionth of a human hair – is allowing scientists to create new materials and think of innovative applications

for them. A group of Indian scientists has developed a nanosheet which can also act like a chemical reducing agent. The discovery can have potential applications in energy storage devices and next-generation sensors.

The research team at the Indian Institute of Technology, Gandhinagar, has found that boron-rich nanosheets, developed by them earlier this year, can also act as a chemical reagent.

During experiments, researchers noticed that boron nanosheets could remain afloat in water for long durations. The nanosheets, they found, were remaining afloat due to hydride groups borrowed from water. This observation led them to a new idea – using nanosheets in place of sodium

Nanosheets can be Chemical Reagents Too

10 | Science Reporter | January 2019

for such a long time by blending themselves with coral and algae-filled habitats around themselves in the ocean. Recently they were photographed by a group of researchers in Izu Island, Japan, and a few of them were brought to their research table for further DNA test.

These tiny Seahorses have only one pair of ‘large truncated spines’ that form awing like structure on their back. The other similar species have two pairs of the same. Another interesting feature of these new species is they have some triangular bony mound on their upper back which is absent in other pigmy seahorses. Though the exact function of these features is yet to be concluded, it is believed that they are used to attract mates, says National Geographic. The Japan pig also sports white and brown lattice pattern which is again different in other similar species.

According to the research study lead author Graham Short of California Academy of Sciences in San Francisco, “these tiny creatures appear quite active and playful”. He also noted that the species are not rare and can be seen in several places throughout the Eastern coast of Japan. He observed that the large-sized Seahorses are diminishing as they are finding places in aquariums and also they are used in Chinese traditional medicinal preparations.

The Seahorses are very tiny and good at slipping by unnoticed. They can fit into our hands in large numbers provided they are not jumping out as racehorses.

Contributed by K.S. Someswara, No.12/B, 6th Cross, Lake City Layout, Kodichikkanahalli, Bengaluru-560076

SEAHORSES are common species that can be found in oceans across the globe. Recently scientists have discovered a new species of Seahorses in Japan. They

named these new species as Hippocampus japapigu (it is the Latin word for Japan Pig). The newly discovered species are tiny by appearance, but they are making large waves with their plain and adorable activities.

The Japan Pig is even smaller than the size of the width of the normal index finger of a human being. A group of researchers’ study on these species was documented and published in the recent issue of the journal Zoo Keys.

The creature’s size is just 15 to 16 mm in length and they join a majestic group of six other known pigmy Seahorses. These colourful species eluded the scientists’ microscopic eyes

Pigmy Seahorses

borohydride, a popular reagent used to chemically reduce gold salt. When gold salt was introduced in dispersion of boron-rich nanosheets, it instantly reduced and formed gold nanoparticles onto nanosheets without the need of any external help.

They found that this can be extended to synthesise platinum and silver nanoparticles by dipping nanosheets in their respective salt solutions. This means boron-rich nanosheets can function as nanoscale factories to manufacture nanoparticles by using metal ions as raw material.

“The formation of nanohybrids with gold and graphene provides the proof of concept that the inherent reducing character of these nanosheets can be availed to create diverse mixed-dimensional heterostructures in solution,” the researchers observed in their study in journal Nanoscale, published by the Royal Society of Chemistry. “Our initial experiments indicate that the noble metal nanoparticle-nanosheet hybrids are excellent electrocatalysts for hydrogen evolution reaction.”

Dr. Kabeer Jasuja, who led the research team, said “this is the first example of a nanosheet that is also a reducing agent, and presents a new perspective on the chemistry of

nanosheets. Our work suggests that we can now design a wide range of boron-based nanohybrids in a test tube. We have shown this capability by preparing a borophene-graphene like interface in solution. The concurrence of reducing nature and planarity makes these nanosheets an intriguing alternative over conventional reducing agents.”

“In essence, we have tamed down the otherwise reactive reducing agent borohydride by virtue of nanosheets. This means that now we have an access to a mild reducing agent for selective reduction of electron rich organic moieties. This research has the potential to open up new avenues in organic synthesis that will be crucial for pharmaceutical and polymer industries,” added Dr. Arnab Dutta, a member of the research team.

The work was supported by seed funding from IIT Gandhinagar, INSPIRE Faculty Award Research Grant, and Core research Grant from the Department of Science and Technology. The team included Asha Liza James, Shikha Khandelwal, Dr. Arnab Dutta and Dr. Kabeer Jasuja.

Dinesh C. Sharma, India Science Wire

January 2019 | Science Reporter | 11

Two Newly Discovered Species of Ginger

BOTANICAL Survey of India (BSI) scientists have discovered two new species of ginger

named Hedychium chingmeianum and Caulokaempferia dinabandhuensis in the easternmost districts of northeast India including Ukhrul in Manipur and Tuensang in Nagaland. Both the plants belong to the family of Zingiberaceae, to which the commonly found ginger (Zingiber officinale) belongs.

Hedychium chingmeianum is an epiphytic plant and grows on trunks of tall trees. It consists of reddish stems and creamy white flowers.

Caulokaempferia dinabandhuensis was found growing in rock crevices, boulders and humus-rich soil in the

Shirui Hills in Ukhrul in Manipur. It has beautiful oval-shaped pink flowers which appear in June-July. It has been named after Mr Dinabandhu Sahoo, Director, Institute of Bioresources and Sustainable Development Department (IBSD), who spotted the species during a trip to Ukhrul hills.

A paper on the discovery was published in Telopea, a peer-reviewed scientific journal.

Out of 44 taxa, 31 species and 13 varieties of genus Hedychium found in India, only five are reported in south India. The remaining species are all found in the northeast. Most of the species of this genus comprise medicinal properties. However, it

Bionic Mushroom

RESEARCHERS, also including Indian origin scientists from Stevens Institute of Technology, US, have bioengineered a “Bionic Mushroom”

capable of producing green power by 3D-printing clusters of cyanobacteria on normal white button mushroom. “Bionic Mushrooms” are the hybrid of nanotech, bacteria and Fungi which are for the first time showing bioengineered symbiosis between two different microbial kingdoms.

Researchers supercharged an ordinary white mushroom by clusters of tightly-packed cyanobacteria, which is known for its ability to produce electricity, and were also equipped with 3-D printed graphene nanoribbons that can collect current.

“In this case, our system — this bionic mushroom — produces electricity,” said Manu Mannoor, assistant professor of mechanical engineering at Stevens. “By integrating cyanobacteria that can produce electricity, with nanoscale materials capable of collecting the current, we were able to better access the unique properties of both, augment them, and create an entirely new functional bionic system,” he added.

“The mushrooms essentially serve as a suitable environmental substrate with the advanced functionality of nourishing the energy-producing cyanobacteria,” said Sudeep Joshi, a postdoctoral fellow in the lab.

A robotic arm-based 3D printer was used to print an “electronic-ink” containing nanoribbons. The printed branched network atop the mushroom’s cap serves as an electricity-collecting network and accesses bio-electrons generated inside the cyanobacterial cells.

Image Credit: agriicarjrf.com

Besides this, a “bio-ink” was also printed having cyanobacteria onto the mushroom’s cap in a spiral pattern which was intersecting the electronic-ink at multiple contact points. At these intersecting points, electrons can transfer through the outer membranes of the cyanobacteria to the conductive branches of graphene nanoribbons. With this, cyanobacteria photosynthesis gets activated by shining of light on the mushrooms.

“With this work, we can imagine enormous opportunities for next-generation bio-hybrid applications,” said Mannoor. “For example, some bacteria can glow, while others sense toxins or produce fuel. By seamlessly integrating these microbes with nanomaterials, we could potentially realise many other amazing designer bio-hybrids for the environment, defence, healthcare and many other fields,” he added.

Source: Stevens Institute of Technology

is yet to be ascertained whether the newly found species of Hedychium chingmeianum has medicinal properties or not.

Contributed by Aanchal Verma, Research Intern, International & Popular Science Division, CSIR-NISCAIR

Densely packed cyanobac-teria (green) achieved via 3D printing increases electricity-generating behaviour; Image Credit: Sudeep Joshi, Ste-

vens Institute of Technology

Image Credit: Sudeep Joshi, Ste-vens Institute of Technology

12 | Science Reporter | January 2019

Mouse Babies with Same-sex Parents

AT the Chinese Academy of Sciences, China, with the help of gene editing and stem cells, same-sex mice couples (two females) have given birth to healthy mice

for the first time, who were then able to reproduce themselves. The study pushes the boundaries of reproductive science.

During the study, mice from two fathers were also born but survived only for 48 hours. While using two mothers, the scientists were successful in producing a total of 29 live, normal, healthy mice from 210 embryos.

During the research, haploid Embryonic Stem Cells (ESC) which consist of half the number of chromosomes and DNA were used which was the key reason for the success of this study. Three imprinting regions of the genome from the haploid ESC consisting of a female parent’s DNA were deleted by the scientists and then injected into the eggs from another female mouse. The same-sex couples produced 29 live mice from 210 embryos. The mice were normal, lived to adulthood, and had babies of their own.

The study published in Cell Stem Cell journal documents the first time the method has been successfully implemented, though previous research used other ways to produce babies from same-sex couples.

The breakthrough research shows barriers to same-sex reproduction in humans can technically be overcome, suggesting stem cells and targeted gene editing can make the process easier.

Source: ScienceDaily

A healthy adult bi-maternal mouse with offsprings of her own; Image Credit: Leyun Wang

Neuromorphic Supercomputer — SpiNNaker

THE world’s largest human-bra in l ike supercomputer — Spiking Neural Network

Architecture (SpiNNaker) — has been built and designed in the University of Manchester’s School of Computer Science, United Kingdom.

SpiNNaker is a supercomputer with the ability to complete more than 200 million actions per second

with each of i t s chips containing 100 million transistors. SpiNNaker works the same as the human bra in mimick ing the brain’s neural n e t w o r k s a n d produces simi lar results to that of the best brain-simulation s u p e r c o m p u t e r software currently used for neura l-signalling research.

U n l i k e conventional computers, Neuromorphic Supercomputer SpiNNaker is unique as it does not communicate by sending large amounts of information from point A to B via a standard network; rather it mimics the massively parallel communication architecture of the brain, sending billions of small amounts of information simultaneously.

A SpiNNaker machine is a massively parallel computing platform, targeted towards three main areas

of research including Neuroscience, Robotics and Computer Science.

One of the main uses of a neuro-morphic supercomputer is to support neurobiologists so that they can better understand how our brain works. This is achieved by running extremely large scale real-time simulations which are not that simple on other machines.

The study has been published in Frontiers in Neuroscience.

Source: apt.cs.manchester.ac.uk

Image credit: apt.cs.manchester.ac.uk

Image credit: apt.cs.manchester.ac.uk

January 2019 | Science Reporter | 13