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Molybdenum disulfide (MoS2) has emerged as a promising material for catalysis and sustainable energy conversion. However, the inertness of its basal plane to electrochemical reactions poses challenges to the utilization of wafer-scale MoS2in electrocatalysis. To overcome this limitation, we present a technique that enhances the catalytic activity of continuous MoS2by preferentially activating its buried grain boundaries (GBs). Through mild UV irradiation, a significant enhancement in GB activity was observed that approaches the values for MoS2edges, as confirmed by a site-selective photo-deposition technique and micro-electrochemical hydrogen evolution reaction (HER) measurements. Combined spectroscopic characterization and ab-initiosimulation demonstrates substitutional oxygen functionalization at the grain boundaries to be the origin of this selective catalytic enhancement by an order of magnitude. Our approach not only improves the density of active sites in MoS2catalytic processes but yields a new photocatalytic conversion process. By exploiting the difference in electronic structure between activated GBs and the basal plane, homo-compositional junctions were realized that improve the photocatalytic synthesis of hydrogen by 47% and achieve performances beyond the capabilities of other catalytic sites.

Two-dimensional (2D) material-based nanoelectromechanical (NEM) resonators are expected to be enabling components in hybrid qubits that couple mechanical and electromagnetic degrees of freedom. However, challenges in their sensitivity and coherence time have to be overcome to realize such mechanohybrid quantum systems. We here demonstrate the potential of strain engineering to realize 2D material-based resonators with unprecedented performance. A liquid-based tension process was shown to enhance the resonance frequency and quality factor of graphene resonators six-fold. Spectroscopic and microscopic characterization reveals a surface-energy enhanced wall interaction as the origin of this effect. The response of our tensioned resonators is not limited by external loss factors and exhibits near-ideal internal losses, yielding superior resonance frequencies and quality factors to all previously reported 2D material devices. Our approach represents a powerful method of enhancing 2D NEM resonators for future quantum systems.

Several letter to the editor are presented on the topics including violence against women, Dadasahab Phalke award honored to Pran Krishna Sikand by Indian film industry, and significance of yoga for health sake.

The report highlights the outcome of the 55th All India Textile Conference, organized by the Textile Association of India (TAI) in 1999. The event was held in December 17 and 18 and was sponsored by the Ministry of Textiles. The theme of the conference was "Emerging Trends on Textile Horizon." President D.R. Mehta of the TAI gave the welcome address stressing the role of the conference in providing ample opportunity to understand the emerging trends and the new industry scenario. Relating to the activities of the association, TIA national president R.K. Dalmia said that the association has a large number of members from the decentralized sectors like powerloom, spinning, process houses, silk and jute industries. Asserting the need to be globally competitive, Dalmia said that the Indian textile industry was passing through a phase of anxiety, compulsion and hazy business forecasts.

In the recent past, investigations are reported on Geopolymer concrete. Geopolymer is known as inorganic polymer. Such materials are useful materials which are capable of replacing constructional materials such as conventional cement. In present investigations, Geopolymer is made from chromium bearing slag obtained from a ferrochrome industry (BRG steel). The mechanism involved is that the silicon and aluminium present in the high carbon ferrochrome (HCFC) slag reacts with alkali liquid, forming Geopolymer which binds other non-reactive materials in the slag. The highest strength level achieved for as-prepared Geopolymers are 11 and 15 MPa by curing 7 days and 28 days, respectively. X-ray diffraction patterns reveal that there is a gradual transformation from crystalline phase to non-crystalline phase which is due to polymeric transformation with increase in curing time. SEM micrographs confirm formation of glassy phases at a higher curing time which also corroborate with mechanical properties such as compressive strength. Distinct changes are observed in FTIR spectra i.e, increase in peak height as well as appearance of many other peaks if compared with FTIR spectrum of virgin material. This strength is due to polymeric reactions and formation of chains with the monomeric structure. Striking features of the TGA pattern is observed for the two materials i.e., uncured and cured samples. DSC isotherms show oozing out of inbuilt water which has accumulated during condensation polymerization reaction. The strength level achieved for optimum combination of variable is found to be comparable to that of standard motar of grade (M15) as is used for constructional purpose.

In present investigations, Geopolymer is made from thermal power plant waste obtained such as Pond Ash. The mechanism involved is that the silicon and aluminium present in the waste reacts with alkali liquid, forming Geopolymer which binds other non-reactive materials in the waste. The highest strength level achieved for as-prepared Geopolymers 19 MPa by curing 1 day. The strength level of Geopolymeric products are 22 MPa (Geopolymeric Motar) and 31 MPa (Geopolymer concrete), respectively. SEM micrographs reveal that there is a gradual transformation from irregular spherical shape to compacted mass which is due to polymeric transformation with increase in curing time which also corroborate with mechanical properties such as compressive strength. DSC isotherms show oozing out of inbuilt water which has accumulated during condensation polymerization reaction. The strength level achieved for optimum combination of variable is found to be comparable to that of standard motar of grade (M15) as is used for constructional purpose.

The in-situ microwave casting of metallic materials is a recently developed casting process. The process works on the principles of hybrid microwave heating and is accomplished inside the applicator cavity. The process involves - melting of the charge, in-situ pouring and solidification of the melt. The electromagnetic and thermal properties of the charge affects microwave-material interaction and hence melting of the charge. On the other hand, cooling conditions inside the applicator controls solidification process. The present work reports on in-situ casting of copper developed inside a multimode cavity at 2.45 GHz using 1400 W. The molten metal was allowed to get poured in-situ inside a graphite mold and solidification was carried out in the same mold inside the applicator cavity. The interaction of microwave with the charge during exposure was studied and the role of oxide layer during meltingthe copper blocks has been presented. The developed in-situ cast was characterized to access the cast quality. Microstructural study revealed the homogeneous and dense structure of the cast. The X-ray diffraction pattern indicated presence of copper in different orientations with (1 1 1) as the dominant orientation. The average micro indentation hardness of the casts was found 93+-20 HV.

Several letters to the editor are presented in response to the article "Some resolve, at last!" in the April 2013 issue on a confession made by Ranjit Sinha, chief of the Central Bureau of Investigation (CBI) of India, on ruling dispensation.

The changes in the duty structure will have significant effect on the competitiveness of the textile industry in India according to representatives of the Association of Merchants & Manufacturers of Textile Stores & Machinery (AMMTSM) during its meeting in Mumbai, India on August 27, 1999. For the purpose of providing a fair competitive ground for Indian textile manufacturers, lowering the basic customs duty on inputs by ten percent below the rate applicable to complete capital goods imported by the user industry is required according to AMMTSM President Narendra Shah. Additionally, Shah mentioned that the government should become more aware of the realistic performance obstacles of Indian textile manufacturers. On the textile machinery and accessories industry, the main concern for the association was the declining trend in production according to Shah.