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Developing environmentally benevolent and sustainable approaches is a vital objective of research in any field. By upholding these parameters and strategizing the methodology, herein we report the development of a new heterogeneous nanocatalyst based on Schiff base functionalized Pd(II) complex onto titania-coated magnetic nanoparticles [Pd@SB/Fe3O4–TiO2]. The developed catalytic system is well characterized with various techniques such as FE-SEM, TEM, XPS, XRD, TGA, BET, FTIR, VSM, CHN, EDX, and ICP-AES analysis. The catalytic activity of [Pd@SB/Fe3O4–TiO2] for the Suzuki coupling reaction to synthesize biaryls and for the hydrogenation reaction of aromatic nitro compounds to synthesize aromatic amines under sustainable reaction conditions was tested which revealed excellent results. Pd@SB/Fe3O4–TiO2 showed remarkably higher activity than the homogeneous PdCl2 and Pd(OAc)2, which might be due to the presence of electronic synergism between support and Pd. Schiff base functionalization provides excellent support to the palladium as leaching of the metal was not observed. The magnetic core of the catalyst ascertains its easy recoverability, thereby maintaining the sustainability of the reaction. The magnetic catalyst was easily separable with the help of an external magnet and showed very good recyclability for up to six cycles with no appreciable loss in catalytic efficiency. Furthermore, the reported catalyst remains unchanged even after six consecutive runs as established by the FTIR, XPS, and XRD analysis of the recovered catalyst. [ABSTRACT FROM AUTHOR]

The present study aims to determine the chronology of the past settlement of the different archaeological sites of the Digaru–Kolong River valley (Assam-Meghalaya Foothills), India, based on accelerator mass spectrometry (AMS) 14C dates of seven charcoal samples, five potsherds, and five sediment samples. The archaeological record of the study area consists of ground and polished stone axes and adzes, pottery, and standing or buried megaliths. The samples analyzed were excavated from test pits, and an attempt has been made to correlate the findings with the chronology of the neighboring archaeological region. A site reported in the vicinity of the study area is primarily Neolithic. However, the results from our excavations indicate a time frame for the analyzed artifacts of ca. 240 CE to 1379 CE. [ABSTRACT FROM AUTHOR]

Twenty nine potsherds from nine Neolithic sites of Northeast India have been analysed using thin section petrography. The primary objectives of this article are to determine their provenance, to investigate the production techniques of Neolithic pottery and to understand the technical skills of the ancient potters of the studied region. Based on their mineralogical content and the composition of the matrices, the pottery samples have been classified into eleven fabric groups. The analysis of the fabrics showed dissimilarities in the processing and production of ceramics which were otherwise very similar at first sight. The dissimilarities provided indications of the clay sources and the occurrence of natural and artificial temper/inclusions, e.g., organic or inorganic substances used by the Neolithic potters of Northeast India during manufacturing processes. In all fabric groups, we found ironbearing materials which show that the ancient potters used local clay to make pottery because the soil in this region contains a high amount of ferruginous substances. The results also confirmed that the analysed pottery was probably fired below 800 °C under an oxidizing atmosphere and also revealed the use of non-plastic inclusions, such as sand, quartz and organic materials during pottery production. [ABSTRACT FROM AUTHOR]

Bimetallic core–shell nano-structured catalysis has sparked great interest due to the multiple possibilities relating to morphology, atomic arrangement, and composition. In the present study, three bimetallic core–shell-based nanocatalysts, viz. Pd(0)@enSiO2–TiO2–Ni, Pd(0)@enSiO2–Ni–TiO2, and Pd(0)@Ni–enSiO2–TiO2, were synthesized via an economical and facile method using Pd(0) and amine-functionalized silica–titania Ni(II) in the shell and core, respectively. The arrangement of Ni(II) was varied in the three nanocatalysts and their catalytic activities were studied for hydrogenation reactions. The best results were obtained in the case of Pd(0)@enSiO2–Ni–TiO2 among all the catalysts. The enhanced catalytic activity of Pd(0)@enSiO2–Ni–TiO2 was demonstrated via surface characterization techniques. Brunauer–Emmett–Teller (BET) analysis depicted the highest surface area in the case of Pd(0)@enSiO2–Ni–TiO2; X-ray photoelectron spectroscopy (XPS) analysis supported the results, as an additional peak from Ni(III) was observed in the spectrum of the reused catalyst, which suggested the presence of electronic interactions between Ni(II) in the core and Pd(0) in the shell. Moreover, Pd(0)@enSiO2–Ni–TiO2 was found to be highly active for carrying out hydrogenation reactions under mild reaction conditions with good yields and high selectivity, and it can be reused for up to five runs. [ABSTRACT FROM AUTHOR]

In this digital era, the internet, and Social Media (SM) has had a radical impact on the shopping behavior of "costumers" The SM provides a platform where "costumers" are exposed to the best product with the best price along with reviews and opinions about the merchandise. So, we can turn our heads and look at a brand in a way as if the brand is speaking to us. This study was an attempt to explore the Social Media Marketing Activities (SMMA) that are being used for the marketing of fashionable products like apparel and to what level the SMMA activities of brands truly strengthen the relationship with customers and motivate purchase intention. Moreover, SMMA has a robust application in developing a marketing strategy for business. It has become a significant tool that collaborates with businesses and people. It is concluded that the "costumer"- brand relationship does have a positive and statistically significant impact on consumers' purchase intention through SM. [ABSTRACT FROM AUTHOR]