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An assembly of metal nanoclusters driven by appropriate surface ligands and solvent environment may engender entirely new photoluminescence (PL). Herein, we first synthesize histidine (His) stabilized copper nanoparticles (CuNPs) and, subsequently, copper nanoclusters (CuNCs) from it using 3‐mercaptopropionic acid (MPA) as an etchant. The CuNCs originally emit bluish‐green (λem=470 nm) PL with a low quantum yield (QY∼1.8 %). However, it transformed into a dual‐emissive nanocluster assembly (Zn‐CuNCs) in the presence of Zn(II) salt, having a distinct blue emission band (λem=420 nm) and a red emission band (λem=615 nm) with eight times QY (∼9.1 %) enhancement. The temperature‐dependent emission spectra of Zn‐CuNCs depicted that the blue emission band persists for all the temperature ranges (0–80 °C) while the red emission band vanishes at high temperatures (70–80 °C). Thus, the blue emission may originate from the locally excited state (LES) emission of the nanoclusters, while the red emission originates from through‐space interaction (TSI) and Cu(I)...Cu(I) interaction within the assembly. Adding dimethyl sulfoxide (DMSO) further modifies the emission intensities; the red band was amplified four times, while the blue band was diminished by 2.5 times. The transmission electron microscopy (TEM) images unveiled that the Zn‐CuNCs are a large assembly of tiny nanoclusters, which become more compact in DMSO. The blue emission possesses steady‐state fluorescence anisotropy, while the red emission shows no anisotropy. Further, near‐perfect white light emission(WLE) was rendered with CIE coordinates of (0.33, 0.32) by combining the dual emission of the Zn‐CuNCs with the original green emission of the CuNCs. [ABSTRACT FROM AUTHOR]

In this present work, a newly designed metal‐oxide nanoparticle incorporated Covalent organic framework (COF), CuxOy@TFP‐ODA has been successfully synthesized and used for the effective synthesis of Oxazolidinones and a‐hydroxy ketones under mild conditions utilizing CO2. Initially, imine‐linked 2D COF, TFP‐ODA was synthesized by simple solvothermal method followed by the embedment of copper oxide nanoparticles (NPs) into the skeleton of the as‐synthesized COF. Different characterization techniques were employed to establish the physical and chemical characteristics of both CuxOy@TFP‐ODA and TFP‐ODA COF materials. To study the catalytic efficiency of the highly porous CuxOy@TFP‐ODA, three components coupling reaction involving primary amine, propargyl alcohol and CO2 to synthesize a series of 2‐Oxazolidinone and synthesis of α‐hydroxy ketones using CO2 as a Co‐catalyst were carried out over the as‐prepared catalyst under green and sustainable conditions which illustrated excellent yields and selectivity of the corresponding products. The synthesized catalyst was proved to be completely heterogeneous and especially, the catalyst material demonstrated significant potential for reuse across several catalytic cycles. [ABSTRACT FROM AUTHOR]

The photocatalytic production of fuels and chemicals utilizing highly effective catalysts has garnered a lot of interest as a sustainable and clean strategy. Herein, we have reported the effective fabrication of an imine-linked covalent organic framework, FP-BTA COF, supported 2D–2D MoS2/FP-BTA heterojunction with molybdenum sulfide (MoS2) utilizing an easy hydrothermal technique. The development of a 2D–2D heterojunction between a covalent organic framework (COF) and molybdenum sulfide (MoS2) with well-matched band positions can efficiently restrict the recombination of the charge carriers and boost the light absorption capacity along with the surface area, which is mainly responsible for the greatly improved catalytic efficiency. This as-prepared MoS2/FP-BTA hybrid photocatalyst demonstrated exceptional dual catalytic efficiency for the oxidative coupling of benzylamine derivatives to generate higher yields (92%) of N-benzylidene benzylamines along with selective reduction of carbon dioxide (CO2) to formic acid (highest generation rate = 43.3 mol gcat−1 h−1) at atmospheric carbon dioxide (CO2) pressure as compared to molybdenum sulfide (MoS2) and the FP-BTA COF without the requirement of any extra sacrificial electron donors under sunlight. The present research also focuses on economically viable, straightforward and sustainable methods for visible-light induced oxidation of a sequence of benzylamines under atmospheric oxygen (O2) utilizing the MoS2/FP-BTA hybrid material and the highest 98% isolated yield of the product containing a mixture of the corresponding imine and carbonyl compounds was achieved under ambient reaction conditions. The photocatalyst produced a good amount of the intended products and was easily recoverable and recyclable up to the fifth run for both reactions. The creation of a single hybrid with a 2D–2D interface by fusing organic and inorganic materials as well as the twin strategy of producing valuable chemicals in a single process may open up new prospects for sustainable development and enhance the atom economy. [ABSTRACT FROM AUTHOR]

The article presents the discussion on significance of groundwater (GW) globally and its management challenges, particularly focusing on India's situation. Topics include highlights the over-exploitation of groundwater resources in India, emphasizing the need for sustainable management practices to address water security issues; and global groundwater significance, challenges in groundwater management, and India's groundwater situation.

Dual-emissive protein-capped metal nanoclusters are emerging nanoprobes for ratiometric sensing. Here, we report dual-emissive bovine serum albumin (BSA)-capped silver nanoclusters (AgNCs) with a blue emission band at 450 nm and a far-red emission band at 680 nm. The blue emission is attributed to the BSA capping, while the far-red emission originates from the AgNCs. The intensity ratio of the two bands is susceptible to the presence of IO4– and Cu2+, allowing selective detection of these analytes with a limit of detection (LOD) of 18.8 and 21.6 nM, respectively. These two analytes display different effects on the emission bands. The blue emission band increases with simultaneous diminution of the far-red band in the presence of IO4–; however, only the far-red emission band decreases in the presence of Cu2+ without altering the blue emission. Both the analytes manifested distinct visual changes in the emission color of the AgNCs solution under a UV lamp, which can also be evident from the shift of the Commission Internationale d'Eclairage (CIE) coordinates from (0.48, 0.32) to (0.18, 0.17) and (0.24, 0.25) for IO4– and Cu2+, respectively. IO4– induced a conformational change in BSA, intensifying the blue emission band along with a dynamic quenching of the AgNCs' emission at 680 nm. In contrast, Cu2+ triggered only a metal exchange method-based quenching of the 680 nm emission with almost no effect on the BSA capping. A smartphone-based on-site detection of IO4– and Cu2+ was also achieved. Inspired by the contrasting fluorescence (Fl) response signals of AgNCs toward IO4– concentration, a simple logic gate circuit was constructed. This investigation will provide important insight into the one-pot synthesis of dual-emissive silver nanoclusters and the ratiometric detection mechanism of IO4– and Cu2+. [ABSTRACT FROM AUTHOR]

It is known that alcoholic beverages alter the human gut microbiome. This study focused on the potential impact of non-ethanolic ingredients in whisky on the gut bacteriome. A pilot study was carried out on 15 whisky drinkers, 5 rice beer drinkers, and 9 non-drinkers to determine the effect of alcoholic beverages on the host microbiome and metabolome. Additionally, a mouse model was used to assess the differential impact of three whisky brands (each with an equal ethanol concentration). The results indicate that the non-ethanolic components have an impact on the gut microbiome, as well as on the metabolites in blood and feces. The amount of Prevotella copri, a typical core Indian gut bacterium, decreased in both the human and mouse groups of whisky type 1, but an increase in abundance of Helicobacteriaceae (p = 0.01) was noticed in both groups. Additionally, the alcohol-treated cohorts had lower levels of short-chain fatty acids (SCFAs), specifically butyric acid, and higher amounts of lipids and stress marker IL1-ß than the untreated groups (p = 0.04–0.01). Furthermore, two compounds, ethanal/acetaldehyde (found in all the whisky samples) and arabitol (unique to whisky type 1), were tested in the mice. Similar to the human subjects, the whisky type 1 treated mouse cohort and the arabitol-treated group showed decreased levels of Prevotella copri (p = 0.01) in their gut. The results showed that non-ethanolic compounds have a significant impact on host gut bacterial diversity and metabolite composition, which has a further vital impact on host health. Our work further emphasizes the need to study the impact of non-ethanolic ingredients of alcoholic beverages on host health. [ABSTRACT FROM AUTHOR]

Abstract We present a very simple and effective way for the synthesis of tunable coloured silver sols having different morphologies. The procedure is based on the seed-mediated growth approach where methyl cellulose (MC) has been used as soft-template in the growth solution. Nanostructures of varying morphologies as well as colour of the silver sols are controlled by altering the concentration of citrate in the growth solution. Similar to the polymers in the solution, citrate ions also dynamically adsorbed on the growing silver nanoparticles and promote one (1-D) and two-dimensional (2-D) growth of nanoparticles. Silver nanostructures are characterized using UV–vis and HR-TEM spectroscopic study. Simulation of the UV–vis extinction spectra of our synthesized silver nanostructures has been carried out using discrete dipole approximation (DDA) method.