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We report the mechanism to enhance the dielectric and ferroelectric behavior of polymer-ceramic composites through surface hydroxylation of 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 (BZT-BCT) ceramic filler-particles embedded in PVDF-HFP copolymer matrix. Varying the hydroxylated h-(BZT-BCT) filler particle-content (φ = 0–40 wt%) in PVDF-HFP copolymer matrix, composite films (of ~75 μm thickness) were prepared. We observed that, with an increase in filler content up to an optimum concentration of 15 wt%, a microstructure with gradually denser particle-arrangement and enhanced particles-polymer surface interaction is exhibited, which leads to improved dielectric and ferroelectric behavior. The energy storage density (728 mJ/cm3 at an electric field of 750 kV/cm) of the composite with 15 wt% of h-(BZT-BCT) is found to be much higher than those of the pure BZT-BCT sample, pure PVDF-HFP copolymer and their composites. Our work demonstrates the method of enhancing the functional properties through a suitable microstructure of composite materials with surface-hydroxylation of filler particles.

We present the water vapor-induced swelling and the emergence of a penetrant-induced glass-like transition in the substrate-supported glassy chitosan thin films. The time evolution of the film thickness under different levels of relative humidity conditions is measured in real-time using a spectroscopic ellipsometer equipped with a humidity cell. In a dry film, the network of chitosan chains is in a glassy state, and upon exposure to water vapor, initially, the film swells by Fickian diffusion of water molecules, which triggers the structural relaxations of the chains. Under higher humidity conditions, a relatively slower evolution of thickness succeeds the initial rapid swelling due to the non-Fickian sorption of water molecules. The swelling characteristics of the polymer films are accounted for by considering the diffusion-relaxation mechanism of chains in the presence of smaller penetrant molecules. The penetrant-induced glass-like transition (Pg), where the polymer film isothermally transits from a glassy to a rubbery state, is determined for pristine and cross-linked chitosan films. Pg is determined from the abrupt change in the rate of swelling observed upon increasing the relative humidity. Chemical crosslinking has an evident influence on the penetrant-induced glass-like transition of the chitosan films. Pg was found to rise sharply for stiffer films with higher cross-linking density.

Achieving a molecular-level understanding of how the structures and compositions of metal–organic frameworks (MOFs) influence their charge carrier concentration and charge transport mechanism—the two key parameters of electrical conductivity—is essential for the successful development of electrically conducting MOFs, which have recently emerged as one of the most coveted functional materials due to their diverse potential applications in advanced electronics and energy technologies. Herein, we have constructed four new alkali metal (Na, K, Rb, and Cs) frameworks based on an electron-rich tetrathiafulvalene tetracarboxylate (TTFTC) ligand, which formed continuous π-stacks, albeit with different π–π-stacking and S⋯S distances (dπ–π and dS⋯S). These MOFs also contained different amounts of aerobically oxidized TTFTC˙+ radical cations that were quantified by electron spin resonance (ESR) spectroscopy. Density functional theory calculations and diffuse reflectance spectroscopy demonstrated that depending on the π–π-interaction and TTFTC˙+ population, these MOFs enjoyed varying degrees of TTFTC/TTFTC˙+ intervalence charge transfer (IVCT) interactions, which commensurately affected their electronic and optical band gaps and electrical conductivity. Having the shortest dπ–π (3.39 Å) and the largest initial TTFTC˙+ population (∼23%), the oxidized Na-MOF 1-ox displayed the narrowest band gap (1.33 eV) and the highest room temperature electrical conductivity (3.6 × 10−5 S cm−1), whereas owing to its longest dπ–π (3.68 Å) and a negligible TTFTC˙+ population, neutral Cs-MOF 4 exhibited the widest band gap (2.15 eV) and the lowest electrical conductivity (1.8 × 10−7 S cm−1). The freshly prepared but not optimally oxidized K-MOF 2 and Rb-MOF 3 initially displayed intermediate band gaps and conductivity, however, upon prolonged aerobic oxidation, which raised the TTFTC˙+ population to saturation levels (∼25 and 10%, respectively), the resulting 2-ox and 3-ox displayed much narrower band gaps (∼1.35 eV) and higher electrical conductivity (6.6 × 10−5 and 4.7 × 10−5 S cm−1, respectively). The computational studies indicated that charge movement in these MOFs occurred predominantly through the π-stacked ligands, while the experimental results displayed the combined effects of π–π-interactions, TTFTC˙+ population, and TTFTC/TTFTC˙+ IVCT interaction on their electronic and optical properties, demonstrating that IVCT interactions between the mixed-valent ligands could be exploited as an effective design strategy to develop electrically conducting MOFs., Through-space charge movement enabled by intervalence charge transfer interactions between π-stacked mixed-valent tetrathiafulvalene ligands creates electrical conductivity in three-dimensional metal–organic frameworks.

Objective: The focus of this research was to establish a validated high-performance thin layer chromatographic (HPTLC) method for analysing Flupirtine maleate and Paracetamol in a combined dosage form. Method: Paracetamol and Flupirtine maleate were measured using a mobile phase of Ethyl acetate: Chloroform (7:5 v/v) at 286 nm. This technique was validated in accordance with the International Conference on Harmonization (ICH) guidelines. Results: The Rf value for paracetamol was 0.31 and 0.52 for Flupirtine maleate in this existing technique. Paracetamol's linearity was found to be in the range of 3250-6500 ng/band, while Flupirtine maleate's linearity was found to be in the range of 1000-2000 ng/band. The method's accuracy was determined by recovery experiments, which revealed a percent recovery of 98 to 102 percent. The % RSD was determined to be less than 2 in the Precision investigation, and the assay result for both compounds was within the limit.

Thiazolidinedione derivative have Antihyperglycemic activity, they are agonists for the peroxisome proliferator-activated receptor (PPAR), which controls glucose synthesis, transport, and utilization via regulating the transcription of insulin-responsive genes. A number of novel insulin sensitizers are currently being researched. Several of these are derivatives of Thiazolidinedione, but others have different chemical structures. In this work, we created some new Thiazolidinedione derivative based on structure–activity relationship as closely as feasible. The Thiazolidine-2,4-Dione derivatives were manually developed and synthesized using the proper synthetic techniques, then tested in vitro for antihyperglycemic action using the Sucrose loading model (SLM) and the Alloxan induced diabetes model (AIDM). The newly synthesized Thiazolidine-2,4-Dione derivative was characterized using infrared (IR) and proton (H) nuclear magnetic resonance. In this study we found that Compound M-4 has a lot of antihyperglycemic action, thus it's a good idea to think about using it as a lead material for the creation of anti-diabetic drugs.

Objective: Synthesis of N-1 Substituted Indolylchalcone Hybrids and evaluation of anti-angiogenic activity using Chorioallantoic Membrane (CAM) Assay. Methods: Claisen-schmidt reaction is used for the synthesis of 30 Indolylchalcone hybrids, it involves condensation of N-1 substituted indole-3-carboxaldehyde and N1 substituted 2-acetyl-benzimidazole. The phase transfer catalyst, a green catalyst such as anhydrous potassium carbonate (K2CO3) and PEG-400 are used in the alkylation and arylation. All synthesized indolylchalcone hybrids were evaluated for their antiangiogenic activity by in vivo-chorioallantoic membrane (CAM) assay method. Results: The synthesized indolylchalcone compounds are evaluated. The morphometric study was carried out as described by Melkonian et al. (2002). The Compounds with code C-2, I-1, I-2 are showing the more potent effect on the dose-dependent assay of CAM. The compounds with code C-1, C-3, E-1 to E-3, M-1 and M-5 shows the significant activity, however, though the compounds with code B-1, B-2, CL-1 and A-5 were showing antiangiogenic effect at 0.1 µM, but does not show any significant activity on dose-dependent assay of CAM. Conclusion: The synthesized Indolylchalcones as shown in the graph possess very good dose-dependent anti-angiogenic activities. The potency of anti-angiogenetic activity shows that methyl>Ethyl>Cl-benzyl>Benzyl>Isobutyl. 2-acetyl benzimidazole analogs have possible future scope to develop as potent angiogenesis inhibitors.

This experimental work was designed to produce a solid state cladding of Aluminium 6063 over AISI 316 stainless steel using friction surfacing. Various parametric combinations considered as the supreme aspects for bonding integrity were used. Successful analysis was made on aluminium coating over stainless steel substrate. The coating strength and bonding integrity were tested taking consumable rods unit dimensions of 14 mm, 18 mm and 22 mm. The deep influence of the axial force and the rotational speed on coating thickness and width was seen. Temperature profile was measured using an infrared thermometer and peak temperature recorded for 14 mm, 18 mm & 22 mm diameter rods were 326 °C, 348 °C and 366 °C respectively. The mechanical bonding strength was examined through vickers micro hardness and bending rest. Hardness value of 138HV and bending strength of 3.2 tons at 90° bent angles were the highest for a 18 mm rod. Analysis of micro structure and interfacial features of the coating using FE-SEM and EDAX techniques showed good molecular interlocking between aluminium and iron particles.

Mg3Sb2 based Zintl compounds are promising thermoelectric materials due to the abundance of magnesium and antimony in nature. However, the main hindrance in realizing the full potential of Mg3Sb2 compounds for thermoelectric applications is the low figure of merit (zT) of p-type Mg3Sb2, in comparison with its n-type counterpart. We report here the enhancement of the thermoelectric properties of p-type Cu and Ag co-doped Mg3Sb2 processed by a solid-state synthesis route. The samples contain α-Mg3Sb2 as a major phase along with elemental Sb as a minor phase. The doped Mg3Sb2 compounds are thermally stable up to 773 K, irrespective of the presence of a small amount of Sb. The co-doping of Ag and Cu in Mg3Sb2 is found to enhance the power factor to 0.8 mW mK−2 and the thermoelectric figure of merit to 0.76 at 673 K. This is the highest figure of merit among doped p-type Mg3Sb2 compounds reported to date. The rattling of the heavy atoms in co-doped Mg3Sb2 is found to significantly reduce the lattice thermal conductivity, which enhances the thermoelectric figure of merit. This work proposes an effective strategy to enhance the zT of p-type Mg3Sb2via Cu–Ag co-doping at Mg sites.

Magnetoelectric (ME) materials exhibit interesting physics with cross coupling between ferroelectric and magnetic order parameters and thus strong potential to be utilized in memory, spintronics and other multifunctional electronic/magnetic devices. Doping of suitable transition metals in ferroelectrics can induce magnetism and ME coupling and modify the physical properties. Here, we report the structural, electronic, magnetic and ME coupling of 3.5, 5 and 7.5 mol% cobalt doped BaTiO3 (BTO) ceramics. X-ray diffraction and Raman spectroscopy indicate that the samples are single phase having a tetragonal crystal structure with P4mm symmetry. The tetragonality ratio is found to decrease with increasing cobalt content. We observed a Fano-like asymmetric peak in the [A1(LO1)] Raman mode at ∼173 cm−1 in all the cobalt doped BTO samples. The cobalt dopants are shown to be uniformly distributed throughout the surface of the samples. We observed a lowering of the ferroelectric transition temperature and increasing diffusivity parameter with increasing cobalt concentration. The electrical properties of all the samples have been investigated in detail by impedance spectroscopy and ac conductivity studies before and after the ferroelectric phase transitions. All the samples show hysteretic ferroelectric behavior with a clear saturation state that decreases with increasing cobalt content. The observed ferroelectricity in these samples is intrinsic in nature. The 3.5% cobalt doped BTO sample exhibits paramagnetic behavior whereas the 5 and 7.5% cobalt doped BTO samples show ferromagnetic ordering below 43 K. The 7.5% cobalt doped BTO samples show significant ME coupling.

Ferroelectric ceramic–polymer composites consisting of Poly Vinyledine Fluoride–Hexa Fluoro Propylene (PVDF-HFP) as polymer host and 0.5Ba(Zr0.2Ti0.8)O3−0.5(Ba0.7Ca0.3)TiO3 (BZT-BCT) ceramics as filler were prepared using solution casting technique. These composites are characterized for structural, microstructural, vibrational, optical, dielectric and ferroelectric properties at various experimental conditions. The electroactive β phase fraction (observed from XRD and FTIR analysis) increases as the filler concentration increases up to 20 wt% of BZT-BCT and above that its value decreases. FTIR results were analyzed to understand the mechanism of enhancement of β phase by the interaction between negatively surface charged ions of filler with the CH2 dipole of polymer matrix. UV–visible spectroscopy also employed to confirm polymer–ceramic filler interaction. Variation of the dielectric constant with different filler concentrations is explained using the percolation theory. Finally, the interplay between the functional properties and the β phase is discussed in detail.

A pyridine/aniline appended unsymmetrical bidentate ligand N-(4-(4-aminobenzyl)phenyl)nicotinamide, investigated in this work has two well-separated coordination sites. Combination of the ligand wi...

Co-rich ZnCo2O4 (ZCO) two-dimensional (2D) nanosheets are decorated with highly porous, glucose-derived, zero-dimensional (0D) interconnected network-like carbon nanospheres (CNS) using an in situ hydrothermal method. The content of CNS in the reaction is varied to produce two different composites (CNS@ZCO-I and CNS@ZCO-II). Their physicochemical properties are examined and compared with those of the pristine-CNS and ZCO samples. The non-stoichiometry of the elements in ZCO of the composites is quantified by X-ray diffraction using a Reitveld refinement and X-ray photoelectron spectroscopy. CNS@ZCO-II is found to be Co-rich in ZnCo2O4 compared to the other samples. The high surface area of the CNS and non-stoichiometry of Zn/Co in the composites provide a short ion/electron transport path distance, high electronic conductivity, additional electrochemical active sites, and stable structural integrity. This viable strategy offers a good interaction between the CNS and ZCO, which translates to better electrochemical activity as an electrode material for energy storage devices. The CNS@ZCO-II composite with a higher CNS concentration shows an excellent electrochemical performance of approximately 1116.24 F g−1 at 0.35 A g−1 (compared to the pristine-ZCO and CNS@ZCO-I composite).

The combination of a flexible pyridine-appended ligand (L1) with 4,4′-bipyridine (L2) and cis-protected Pd(II) units, Pd(L′)(NO3)2 in water yielded a concentration-dependent equilibrium mixture of ...

Conventional agricultural practices that rely heavily on blanket fertilizer recommendation, eventually leading to deteriorated partial factor productivity and N use efficiency. We investigated the effect of SPAD-based N-management on productivity and N use efficiency of rice and wheat in eastern India. Here, in the experiment three SPAD thresholds (34, 36 and 38 in rice and 38, 40 and 42 in wheat) using three N levels (15, 25 and 35 kg N ha−1) in split were incorporated as real-time N management (RTNM), one fixed-time N management (FTNM), farmers’ fertilizer practice (FFP) and control (No fertilizer) were introduced in wet and dry seasons for rice and wheat, respectively, during the years 2010 to 2012. Topdressing with 25 kg N ha−1 at medium SPAD (S36 in rice and S40 in wheat) increased soil N availability, leaf N content and grain yield of rice (5215 kg ha−1) and wheat (4483 kg ha−1) over the grain yield recorded under a low rate of N topdressing at low SPAD. While saving 33.3% N in rice and 18.8% N in wheat, the agronomic N use efficiency (58.5% in both rice and wheat) and nitrogen recovery efficiency (32.2% in rice and 15.1% in wheat) can be increased when compared with conventional FTNM. The SPAD-based management strategy showed great promise in efficient management of N fertilizer, and we estimated the optimal SPAD threshold for rice and wheat as 37.5 and 41.8, respectively.

Production of improved valued tea is in high demand due to its pharmacological properties against various neurodegenerative diseases like Alzheimer’s disease. In this study, an attempt was made to compare the protective effect of the tea grown under organic and inorganic nutrient management practices against intra-cerebroventricular (i.c.v) colchicine induced memory impairment and oxidative damage in rat model of Alzheimer’s disease (AD). Results showed that chronic intraperitoneal (i.p) administration of tea extract (20 mg/kg i.p) significantly improved the cognitive dysfunction and memory impairment in colchicine treated AD rat model. This beneficial effect occurred with an increase in α-secretase activity, Superoxide dismutase, Catalase activities, and a decrease in Acetylcholinesterase level, Aβ -42 level, Cox-2-linked neuro-inflammation by intraperitoneal injection of tea extract grown organically and inorganically. The amyloid Aβ concentration in the rat model of AD was 84 ± 1.7 pg/mg protein. With administration of tea extract, the amyloid Aβ concentration decreased significantly to 55 ± 1.5, 52 ± 1.3 and 49 ± 1.5 pg/mg protein with the field level management of inorganic, integrated and organic nutrients, respectively. In this study celecoxib (20 mg/kg i.p) is used as a reference standard. This study stated organic tea as a promising neuroprotective agent or adjuvant to prevent AD.

A self-assembled coordination cage usually possesses one well-defined three-dimensional (3D) cavity whereas infinite number of 3D-cavities are crafted in a designer metal-organic framework. Construction of a discrete coordination cage possessing multiple number of 3D-cavities is a challenging task. Here we report the peripheral decoration of a trinuclear [Pd3L6] core with one, two and three units of a [Pd2L4] entity for the preparation of multi-3D-cavity conjoined-cages of [Pd4(La)2(Lb)4], [Pd5(Lb)4(Lc)2] and [Pd6(Lc)6] formulations, respectively. Formation of the tetranuclear and pentanuclear complexes is attributed to the favorable integrative self-sorting of the participating components. Cage-fusion reactions and ligand-displacement-induced cage-to-cage transformation reactions are carried out using appropriately chosen ligand components and cages prepared in this work. The smaller [Pd2L4] cavity selectively binds one unit of NO3−, F−, Cl− or Br− while the larger [Pd3L6] cavity accommodates up to four DMSO molecules. Designing aspects of our conjoined-cages possess enough potential to inspire construction of exotic molecular architectures., Developing simple routes for construction of multi-compartmental cages is a compelling and challenging task. Here, the authors report modular construction of multi-3D-cavity cages featuring one, two or three units of a [Pd2L4] entity conjoined with a [Pd3L6] core.

Sustainable crop production in sub-tropical countries is severely affected by the unscientific application of fertilizers. The SPAD based N management of the rice–wheat sequence was investigated in eastern India. Topdressing of 25 kg N ha−1 was applied at SPAD 36 and 40 (S36 and S40) for rice (Oryza sativa L.) and wheat (Triticum aestivum L.), respectively, reduced the N requirement by an average of 26.5% (33.3% in rice and 18.8% in wheat) over the fixed-time N management (FTNM) without reducing the grain yield. The 25 kg N ha−1 increased nutrient removal in the system having high agronomic N use efficiency (21.4) and nitrogen recovery efficiency (0.60) with the lower N requirement (62.5 kg N ha−1) over the FTNM. The treatment with medium SPAD (S36 for rice and S40 for wheat) under 25 kg N ha−1 increased the agronomic N use efficiency by 58% in rice and 58.5% in wheat compared to that under FTNM and recorded the highest gross (2106.1$ ha−1 Year−1) and net (1202.5$ ha−1 Year−1) returns from the rice–wheat system. The SPAD-based N management increased the water content in N-treated plots compared to that in the control plots, and the utmost moisture custody was observed when using a moderate (25 kg ha−1) N topdressing at a moderate SPAD (S36 for rice and S40 for wheat) for a given soil suction. This study suggests that using SPAD meter in rice–wheat system can cover the productive N management and profitability and can be dependably used in precision agriculture to manage the spatial variation in farmers’ field.

To diversify metal-organic framework (MOF) structures beyond traditional Euclidean geometries and to create new charge-delocalization pathways beneficial for electrical conductivity, we constructed a novel double-helical MOF (dhMOF) by introducing a new butterfly-shaped electron-rich π-extended tetrathiafulvalene ligand equipped with four benzoate groups (ExTTFTB). The face-to-face oriented convex ExTTFTB ligands connected by Zn2(COO)4 paddlewheel nodes formed ovoid cavities suitable for guest encapsulation, while π-π-interaction between the ExTTFTB ligands of neighboring strands helped create new charge-delocalization pathways in iodine-mediated partially oxidized dhMOF. Iodine vapor diffusion led to oxidation of half of the ExTTFTB ligands in each double-helical strand to ExTTFTB•+ radical cations, which putatively formed intermolecular ExTTFTB/ExTTFTB•+ π-donor/acceptor charge-transfer chains with the neutral ExTTFTB ligands of an adjacent strand, creating supramolecular wire-like charge-delocalization pathways along the helix seams. In consequence, the electrical conductivity of dhMOF surged from 10-8 S/m up to 10-4 S/m range after iodine treatment. Thus, the introduction of the electron-rich ExTTFTB ligand with a distinctly convex π-surface not only afforded a novel double-helical MOF architecture featuring ovoid cavities and unique charge-delocalization pathways but also, more importantly, delivered a new tool and design strategy for future development of electrically conducting stimuli-responsive MOFs.

Cuprous oxide and copper have been synthesized via the solvothermal process using basic copper carbonate as the source of copper. Pure Cu2O or Cu could be afforded by simply varying the solvent while keeping the temperature and time constant. In this study, copper-based materials were coated on jute stick pieces (JSP) in situ. Cu2O-coated JSP (Cu2O-JSP) and Cu-coated JSP (Cu-JSP) were characterized by powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). Cu2O-JSP and Cu-JSP were found to be active against Escherichia coli NCIM 2931 (Gram-negative bacteria) and Staphylococcus aureus (Gram-positive bacteria). The antibacterial nature of the material and the buoyant nature of Cu2O-JSP and Cu-JSP were exploited to develop beaded necklace-like strands that could be floated on potable water to effectively prevent aerial contamination. Leaching of copper from both Cu2O-JSP and Cu-JSP into water was found to be below the permissible limit for copper in drinking water.

Aerobic rice cultivation has gained recognition for resource conservation and ecosystem services. However, aerobic/partially-aerobic rice productivity is often constrained by several deficiencies in soil-plant system including phosphorus (P), because of reduced soil P dissolution and crop P acquisition. The study aimed to design sustainable P management option(s) for non-flooded rice [system of rice intensification (SRI)]-lentil system in an alkaline Fluvisol by evaluating the effect of system-based sole fertilizer-P and integrated P management treatments on crop yields, soil P dynamics, P pools, soil biophysical and biochemical attributes. The treatments consisted of one control and three variable seasonal distribution sole fertilizer-P treatments [subscript value (kg P ha−1)] in non-flooded rice (SRI)-lentil (L) rotation ([SRI0-L0], [SRI22-L22], [SRI33-L11], [SRI11-L33]), three integrated P management treatments ([SRI11-L11+phosphate solubilizing bacteria (PSB)], SRI16.5-L5.5+rice residue incorporation (RR)+PSB, SRI5.5-L16.5+lentil residue incorporation (LR)+PSB)]. Besides this, a conventional flooded rice-lentil system with the recommended sole fertilizer-P rate ([PTR22-L22]) as a treatment was evaluated to compare soil P dynamics in flooded versus non-flooded rice ecologies. Soil P availability was significantly reduced (7–8%) in the non-flooded rice compared to the flooded rice ecology. The integrated treatment involving suboptimal fertilizer-P rate (22 kg P ha−1y−1), rice residue recycling, and PSB increased soil P availability in rice (5-6%) and lentil (9-10%) seasons as well as system productivity by 8.3% over the recommended sole fertilizer-P treatment ([SRI22-L22], 44 kg P ha−1y−1). The rice residue recycling integrated treatment increased NaHCO3-Pi (11%) and dissolved non-reactive P (6%) over the recommended sole fertilizer-P treatment. The positive effects of the lentil residue recycling integrated treatment on soil P availability and crop yields were relatively lower than the rice residue recycling integrated treatment possibly because of the lower residue C-input. Correlation results indicate that microbial biomass carbon, soil aggregation and labile organic carbon have a positive influence on P availability in this alkaline soil. The significant positive correlation between the active C-pool and total dissolved non-reactive P suggested that oxidisable C input could improve bioavailable P forms. Results indicated the role of balanced P fertilization in C-stabilization, which had the lowest in the P control treatment. The study with one soil type suggested that in-situ crop residue recycling integrated P management (rice residue in particular) could be a sustainable option for improving P bioavailability, nutrient cycling, and productivity of non-flooded rice-legume system in tropical alkaline soil, but, for the validation of the results, more studies with diverse soil properties are warranted.

A procedure for practical synthesis of CuNPs from CuSO4·5H2O is established, under appropriate reaction conditions, using rice (Oryza sativa) as an economic source of reducing as well as a stabilizing agent. Optical and microscopic techniques are employed for the characterization of the synthesized CuNPs and the sizes of the particles were found to be in the range of 8 ± 2 nm. The nanoparticles are used as a catalyst for chemoselective reduction of aromatic nitro compounds to corresponding amines under ambient conditions and water as a reaction medium. CuNPs are synthesized using hydrolysed rice and used as catalyst for chemoselective reduction of nitroarenes to their corresponding amines in water.

Photoinduced electron and energy transfer through preorganized chromophore, donor, and acceptor arrays are key to light-harvesting capabilities of photosynthetic plants and bacteria. Mimicking the ...

A surfactant based oxodiperoxo molybdenum complex, which could activate molecular oxygen, has been employed as a catalyst for controlled oxidation of benzylic alcohols to corresponding carbonyls. The oxidation reactions were carried out under aqueous environment, however, in the absence of any extraneous base or co-catalyst. Sensitive/oxidizable functional groups like cyano, sulfide, hydroxyl, aryl-hydroxyl, alkene (internal/terminal), alkyne (internal/terminal), and acetal were tolerated during the transformations. Such selectivity is attributed to the mild nature of the catalyst. The methodology could also be scaled-up for multi-gram synthesis and the protocol is likely to find practical use since it requires an inexpensive recyclable-catalyst and easily available oxidant (under green conditions). A plausible mechanism is proposed with the help of preliminary computational study.

Very recently, it was suggested that non-aqueous acetonitrile/AOT/n-heptane microemulsions may undergo a interfacial transition from reverse micelle (RM) to bi-continuous microemulsion (BMC) above an intermediate ws (= [acetonitrile]/[AOT]). Herein, we develop a unique strategy for probing interfacial transition of the microemulsion by using microemulsion as a template for synthesis of hydrophobic silver colloids. Precursors (silver nitrate) and reducing agents (ascorbic acid) are insoluble in n-heptane phase and thus, Ag colloids formation occur solely inside the acetonitrile fraction and therefore, the structural morphology of the Ag colloids provides valuable information regarding the structure of the template where Ag colloids formation occur. At low ws (≤ 1), synthesized silver colloids exhibits remarkably strong surface plasmon resonance (SPR) band but the strength of SPR remarkably drops at ws = 2 and almost vanishes at ws = 3. TEM measurements revealed the presence of isolated spherical monodispersed silver nanoparticles (AgNPs) of ∼6 nm diameter at lower ws and larger distribution of nanoparticle sizes at ws = 2. Most interestingly, interconnected Ag colloids packed channels were found at ws = 3 which directly shows footprint of the BMC nature of the microemulsion template. Thus, the characteristics of Ag colloids (i.e. size distribution and optical quality) provide valuable information about interfacial structure of the microemulsion and suggested that microemulsion switches from RM to BMC nature at an intermediate ws.

Background: Aminoacyl-tRNA synthetases play an important role in catalyzing the first step in protein synthesis by attaching the appropriate amino acid to its cognate tRNA which then transported to the growing polypeptide chain. Asparaginyl-tRNA Synthetase (AsnRS) from Brugia malayi, Leishmania major, Thermus thermophilus, Trypanosoma brucei have been shown to play an important role in survival and pathogenesis. Entamoeba histolytica (Ehis) is an anaerobic eukaryotic pathogen that infects the large intestines of humans. It is a major cause of dysentery and has the potential to cause life-threatening abscesses in the liver and other organs making it the second leading cause of parasitic death after malaria. Ehis-AsnRS has not been studied in detail, except the crystal structure determined at 3 Å resolution showing that it is primarily α-helical and dimeric. It is a homodimer, with each 52 kDa monomer consisting of 451 amino acids. It has a relatively short N-terminal as compared to its human and yeast counterparts. Objective: Our study focusses to understand certain structural characteristics of Ehis-AsnRS using biophysical tools to decipher the thermodynamics of unfolding and its binding properties. Methods: Ehis-AsnRS was cloned and expressed in E. coli BL21DE3 cells. Protein purification was performed using Ni-NTA affinity chromatography, following which the protein was used for biophysical studies. Various techniques such as steady-state fluorescence, quenching, circular dichroism, differential scanning fluorimetry, isothermal calorimetry and fluorescence lifetime studies were employed for the conformational characterization of Ehis-AsnRS. Protein concentration for far-UV and near-UV circular dichroism experiments was 8 µM and 20 µM respectively, while 4 µM protein was used for the rest of the experiments. Results: The present study revealed that Ehis-AsnRS undergoes unfolding when subjected to increasing concentration of GdnHCl and the process is reversible. With increasing temperature, it retains its structural compactness up to 45ºC before it unfolds. Steady-state fluorescence, circular dichroism and hydrophobic dye binding experiments cumulatively suggest that Ehis-AsnRS undergoes a two-state transition during unfolding. Shifting of the transition mid-point with increasing protein concentration further illustrate that dissociation and unfolding processes are coupled indicating the absence of any detectable folded monomer. Conclusion: This article indicates that GdnHCl induced denaturation of Ehis-AsnRS is a two – state process and does not involve any intermediate; unfolding occurs directly from native dimer to unfolded monomer. The solvent exposure of the tryptophan residues is biphasic, indicating selective quenching. Ehis-AsnRS also exhibits a structural as well as functional stability over a wide range of pH.

The complexation study of cis-protected and bare palladium(II) components with a new tridentate ligand, i.e., pyridine-3,5-diylbis(methylene) dinicotinate (L1) is the focus of this work. Complexation of cis-Pd(tmeda)(NO3)2 with L1 at a 1:1 or 3:2 ratio produced [Pd(tmeda)(L1)](NO3)2 (1a). The reaction mixture obtained at 3:2 ratio upon prolonged heating, produced a small amount of [Pd3(tmeda)3(L1)2](NO3)6 (2a). Complexation of Pd(NO3)2 with L1 at a 1:2 or 3:4 ratios afforded [Pd(L1)2](NO3)2 (3a) and [(NO3)2@Pd3(L1)4](NO3)4 (4a), respectively. The encapsulated NO3– ions of 4a undergo anion exchange with halides (F–, Cl– and Br– but not with I–) to form [(X)2@Pd3(L1)4](NO3)4 5a–7a. The coordination behaviour of ligand L1 and some dynamic properties of these complexes are compared with a set of known complexes prepared using the regioisomeric ligand bis(pyridin-3-ylmethyl)pyridine-3,5-dicarboxylate (L2). Importantly, a ligand isomerism phenomenon is claimed by considering complexes prepared from L1 and L2.

Free standing and flexible ferroelectric ceramic-polymer composites (PVDF+ ϕ wt.% of BNBT (0.94Na0.5Bi0.5TiO3-0.06BaTiO3)) with 0–3 connectivity were synthesized by solution-casting technique. Composite nature and homogeneous distribution of ceramic filler particles in PVDF were confirmed with x-ray diffraction and scanning electron microscopic analysis. The intensity ratio of β-phase with respect to α–phase i.e., I20.2°/I18.4° (obtained from XRD analysis) and the fraction of electro-active beta phase i.e., F(β)% (obtained from FTIR analysis) are enhanced with increase in filler concentrations and peaked for 35 wt% of the ceramic filler. An enhancement of the % of crystallinity (calculated from XRD analysis) has been observed with increase in the filler concentrations. The increase of the fraction of β-phase has been explained on the basis of ion (negatively charged surface ion of the ferroelectric ceramic filler) -dipole (-CH2 dipole of the polymer matrix) interactions, as evidenced from FTIR and UV-VIS absorbance spectra. Relative dielectric permittivity (dielectric constant) and ferroelectric polarization were found to be highest for the composite with 35 wt% of ferroelectric ceramic filler. Percolation theory has been successfully employed to explain the observed trend in the dielectric properties with the compositional variation. Significant enhancement in the electro active β-phase has been correlated with the improved dielectric and ferroelectric properties of the composite.

Elevated CO2 might have differential impact on the growth, development, and yield of wheat under varying nutrient management, especially in a warmer climate when the global atmospheric temperature is already increasing. Field experiments were conducted in subtropical Eastern India during the rabi seasons of 2014–2016 to study the performance of wheat under the elevated CO2 environment with different nitrogen (N) management. Wheat was grown in open field and inside open top chambers (OTCs) with ambient (˜390 μmol mol−1) and elevated (˜585 μmol mol−1) level of CO2 without any fertilizer addition (N0), and with application of N through chemical fertilizer (CF) at normal (100%) recommendation [N100(CF)] and 50% higher dose [N150(CF)] and through integration of organic and chemical fertilizer [N150(OF + CF)]. Results showed that CO2 enrichment had a positive effect on various growth parameters and yield attributes of wheat. Elevated CO2 tended to increase the crop growth rate and the fraction of leaf biomass and leaf N, especially for the N management using chemical fertilizer [N100(CF) and N150(CF)]. Elevated CO2 [+˜200 μmol mol−1] caused 17% increase in wheat grain yield above ambient as averaged over the N fertilized treatments. Application of N at 50% higher dose than normal through CF did not increase the grain yield significantly under the open field and OTC with ambient [CO2] environment, whereas the yield increment was significant under the elevated [CO2] environment. Elevated CO2 also resulted in higher agronomic N use efficiency and nitrogen harvest index with the increased N fertilizer dose. Thus, wheat production under the elevated CO2 environment in Eastern India might be maintained or improved through the normal and increased dose of N fertilizer application.

Lithium ion-conducting metal–organic frameworks (MOFs) are rapidly gaining interest because of their potential application as ion-permeable, robust electrode separators in rechargeable batteries, arguably the most ubiquitous portable clean energy storage devices developed to date. A novel, water-stable 2D sheet-like neutral Cu(I)–sulfonate MOF featuring π-acidic naphthalenediimide (NDI) ligands that can simultaneously bind guest lithium ions with its carbonyl and uncoordinated sulfonate oxygen atoms and charge diffuse perchlorate anions through anion−π interaction has been constructed. While the pristine MOF pellets displayed poor intrinsic electrical conductivity (4.65 × 10–10 S/m) at room temperature due to inadequate charge carrier density and electron delocalization pathway, upon infiltration of LiClO4, its ionic conductivity surged almost million times to 2.3 × 10–4 S/m, and the activation energy for charge carrier transport dropped to a mere 0.167 eV. In contrast, the conductivity of Bu4NClO4-treate...

Objective: The purpose of the present study was a characterization of chitosan (CS)-polypyrrole (PPY) nanocomposites for controlled release of anticancer drug doxorubicin (DOX). Methods: Chitosan crosslink with PPY with montmorillonite (MMT) called as (CS-PPY/MMT) were formulated using the solvent casting method. The prepared nanocomposites were characterized by X-Ray Diffraction Analysis (XRD), tensile strength, scanning electronic microscope (SEM). Results: The XRD result confirmed that the CS-PPY/MMT possessed crystal structure. The nanocomposites CS-PPY/MMT-4 were showed a homogenous morphology. The Water uptake and swelling ratio of the CS-PPY and CS-PPY/MMT were found to decrease with increase in the concentration of clay. Mechanical properties of the CS-PPY and CS-PPY/MMT were assessed in terms of tensile strength and extensibility using texture analyzer. Increase in tensile strength and reduction in extensibility was reported with an increase in the nanoclay content. In vitro drug release study on CS-PPY and CS-PPY/MMT indicated pronounced sustained release of doxorubicin by the incorporation of clay particles in CS-PPY/MMT. It was observed that during the first 60 min of the dissolution study, the CS-PPY/MMT-4 film showed just 79.32±0.56% drug release as while the CS-PPY-1, CS-PPY/MMT-2 and CS-PPY/MMT-3 films showed a release of 53.79±1.23%, 63.51±1.24% and 68.15±2.38% respectively. Conclusion: CS-PPY/MMT nanocomposite films exhibited improved mechanical and sustained drug release properties than CS-PPY. The combination of biodegradable polymeric chains and clay reinforcement can be applied to achieve the desired combination of properties of materials used as a biosensor for diverse biomedical applications.

A noncovalent interaction based self-assembled ruthenium (II) phthalocyanine (RuPc) and N-pyridyl-peryleneimide (PyPMI) dyad has been exploited to fabricate n-type dye-sensitized solar cells (DSSCs). This supramolecular dyad design is an alternative method to replace the most challenging synthesis of covalent-linked dyads. Metal-coordinated-based dyad complex improved the light-harvesting properties of the photoanodes as opposed to when individual dye anchored on TiO2 surface alone. DSSCs comprise of RuPc⋅PyPMI dyad convert light-to-electrical energy more efficiently (η = 2.29%) than those made of single dye under one sun irradiation (100 mW cm−2) condition. The enhanced photovoltaic performance of the dyad-based devices is due to the broader light absorption of the dyad in the longer wavelengths, enabling better electron injection into the conduction band of TiO2. The combined effect of efficient electron-hole charge separation and the long-lived charge-separated states facilitated the higher short-circuit current density (Jsc) and open-circuit voltage (Voc) of the devices. The enhancement of Voc and Jsc of the devices is confirmed by measuring current–voltage (I–V) curve and incident photon to current conversion efficiency (IPCE) spectrum of each device.

A series of binuclear palladium(II)-based self-assembled metallomacrocycles of Pd2L′2L2 type compositions were synthesized by complexation of an imidazole appended non-chelating bidentate ligand L with different cis-protected palladium(II) components (i.e. PdL′). The complexes [Pd2(en)2(L)2](NO3)4, 1, [Pd2(tmeda)2(L)2](NO3)4, 2, [Pd2(bpy)2(L)2](NO3)4, 3, and [Pd2(phen)2(L)2](NO3)4, 4 were characterized by NMR spectroscopy and their nuclearities were established with the help of ESI-MS. Solid state structures of the complexes 2, 3 and [Pd2(phen)2(L)2](OTf)4, 4′, were established by the single-crystal XRD technique. These metallomacrocycles could act as tectons for crystal engineering by using the available π-surface on their architectures. The crystal packing of these molecules revealed the importance of the π-surface on the ligand moiety as well as on the cis-protecting moiety. Utilization of the π-surfaces afforded 1D to 3D supramolecular networks in solid state.

Our understanding of crop response to elevated [CO2] concerning its growth and yield has improved significantly. However, little is known about the germination and vigour of seeds harvested from mother plant grown under elevated [CO2], particularly in rice. Since elevated [CO2] influences the physiological functions of crop and seed development process, it is expected that such changes will alter the quality of the seed. To test this hypothesis, rice crop (IR 36) was grown in open top chamber (OTC) with varying [CO2] [410 (ambient), 510, 610 and 720 ppm] and seed quality in terms of germination and vigour [accelerated ageing test (AAT) and electrical conductivity (EC)] was assessed. Elevated [CO2] up to 610 ppm had no effect on seed germination; but, [CO2] at 720 ppm reduced the germination of freshly harvested seeds. Elevated [CO2] at 610 and 720 ppm reduced seed vigour. An increase in abnormal seedlings and dead seeds were symptomatic of the seed physiological deterioration associated with loss of seed vigour. Elevated [CO2] at 720 ppm reduced seed nitrogen content, substrate availability, and its subsequent translocation. Thus, atmospheric [CO2] above 610 ppm reduced seed vigour of rice.

We report a systematic investigation of the microstructure and thermoelectric properties of refractory element-filled nanostructured Co4Sb12 skutterudites. The refractory tantalum (Ta) metal-filled Co4Sb12 samples (Ta x Co4Sb12 (x = 0, 0.4, 0.6, and 0.8)) are synthesized using a solid-state synthesis route. All the samples are composed of a single skutterudite phase. Meanwhile, nanometer-sized equiaxed grains are present in the Ta0.2Co4Sb12 and Ta0.4Co4Sb12 samples, and bimodal distributions of equiaxed grains and elongated grains are observed in Ta0.6Co4Sb12 and Ta0.8Co4Sb12 samples. The dominant carrier type changes from electrons (n-type) to holes (p-type) with an increase in Ta concentration in the samples. The power factor of the Ta0.6Co4Sb12 sample is increased to 2.12 mW/mK2 at 623 K due to the 10-fold reduction in electrical resistivity. The lowest lattice thermal conductivity observed for Ta0.6Co4Sb12 indicates the rattling action of Ta atoms and grain boundary scattering. Rietveld refinement of XRD data and the analysis of lattice thermal conductivity data using the Debye model confirm that Ta occupies at the voids as well as the Co site. The figure of merit (ZT) of ∼0.4 is obtained in the Ta0.6Co4Sb12 sample, which is comparable to single metal-filled p-type skutterudites reported to date. The thermoelectric properties of the refractory Ta metal-filled skutterudites might be useful to achieve both n-type and p-type thermoelectric legs using a single filler atom and could be one of replacements of the rare earth-filled skutterudites with improved thermoelectric properties.

The present work exhibits the correlation between process variables and coating geometry on friction surfaced deposition of aluminium 6063 over IS 2062 low carbon steel. A 33 factorial design technique and RSM were carried out through Taguchi method using Minitab software. Furthermore the existence model was validated by corresponding collateral experiments. Impact of discrepancy in Axial force (4, 5, 6 kN), Rotational speed (1500, 2000, 2500 rpm) and Transverse speed (75, 150, 300 mm/min) on coating width, thickness, interface temperature and bond strength was investigated. Results showed that at optimum condition of rotational speed 2500 rpm, axial force 5 kN and transverse speed 75 mm/min, the observed coating width = 20.24 mm, thickness = 2.42 mm, interface temperature = 408 °C and bond strength = 92.2 Mpa, respectively. Mechanical strength of the coating was analyzed by push-off test and hardness test which shown a higher hardness value at substrate coating interface than mechtrode material.

A procedure for the expedient synthesis of well-characterized Cu(I) oxide nanoparticles (Cu2ONPs) from Cu(II) salts by employing Rice (Oryza sativa) as a cheap and ready source of reducing as well as stabilizing agent has been demonstrated. The judicious choice of rice as a catalyst has helped in the symbiotic combination of two events: viz., acidic hydrolysis of starch to form glucose and the subsequent formal reduction of Cu2+ by the in-situ generated monosaccharide reducing sugar (glucose) under the alkaline condition to produce Cu2O. Further, rice was also found to be effectively stabilizing the nanoparticles from agglomeration. Optical and microscopic techniques were suitably employed for the characterization of the nanoparticles of approximately 10 nm size. Furthermore, the specifically generated nanoparticles were found to be active catalysts in an aqueous medium for Azide-alkyne Huisgen cycloaddition (Click reaction) under base free condition via one-pot multi-component addition for the synthesis of mono-, bis- and tris-1,2,3-triazoles in good to excellent yields. Cu2ONPs synthesized using hydrolysed Rice, an active catalyst for synthesis of mono-, bis- and tris-1,4-disubstituted 1,2,3-triazoles via one pot multicomponent reactions in water.

In the cement concrete industry, everybody is concerned about high-strength and high-performance behavior of concrete. These properties were improved using micro- and nano-sized pozzolanic mineral admixtures as stated by various authors. In this paper, author has emphasized mostly on using micro- and nanosilica materials with cement. Literature survey revealed that the most suited mineral admixtures for getting highest behaviors are micro- and nanosilica. Nanotechnology is nowadays a buzzword in everyone’s tips. Nanotechnology in concrete means the addition of nano-sized materials in the range of 1 and 100 nm to improve the behavior of cement and concrete. Micro- and nano-sized silica particles improve the porous behavior of concrete and also produce more calcium silicate hydrate resulting from chemical reaction of nanoparticles and calcium hydroxide. On the other hand, it makes concrete more compact in microstructure point of view, which improves density, strength, and also durability. This paper also discusses the synergic behavior of nanosilica and microsilica on the property of concrete in comparison with traditionally produced concrete.

One of the best alternative binder in place of Portland cement is geo-polymer binder. In geo-polymer binder, the main constituent is fly ash which is rich in silicate and alumina. It reacts with sodium hydroxide/silicate solution to produce alumina silicate gel. This gel binds the fine aggregate to form a good paste-like mortar called geo-polymer mortar (GPM). In this paper, the influence of lime and silica fume towards the strength enhancement of GPM mortar has been studied. Most of the author emphasized on hot curing rather than ambient curing for achieving high strength of geo-polymer matrix. This paper also works out to optimize the sodium silicate to hydroxide proportion, molarity of NaOH, various percentage replacement of lime and silica fume partially with fly ash on enhancement of strength of GPM. It was found out that the compressive strength value increased on increase of molarity of NaOH from 6 to 12 M; similarly, for sodium silicate to sodium hydroxide ratio at 2:1 and also at 7.5 and 3% of lime and silica fume replacement, respectively, better strength was shown.

The wheel rim plays a vital role for good running of the vehicle and the most important safety components from a structural point of view. It must be made with adequate strength and lighter in weight to reduce the unsprung mass of the vehicle and plays a major role in vehicle dynamics. The present study deals with the comparison of structural analysis of aluminium bronze alloy wheel rim with three different compositions to enhance corrosion and fatigue resistance. The design of the wheel rim was created by CATIA V5 and structural behaviour was analysed by ANSYS workbench. The results showed that combination of 90% Al alloy and 10% CuSn) gives adequate strength compared to other combinations of aluminium and bronze. The fabrication of the rim was done by casting methods. Various test like impact, shear, hardness and ultimate tensile tests were conducted to know the mechanical strength of the rim. Salt spray corrosion test was carried out to know the corrosion behaviour of the rim and the results show that no corrosion was found up-to 240 hours

Conformations of disulfide and diselenide were compared in (Boc-Cys/Sec-NHMe)2 and (Boc-Cys/Sec-OMe)2 using X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, density functional theory (DFT), and circular dichroism (CD) spectroscopy. Conformations of disulfide/diselenide in polypeptides are defined based on the sign of side chain torsion angle χ3 (-CH2 -S/Se-S/Se-CH2 -); negative indicates left-handed and positive indicates right-handed orientation. In the crystals of (Boc-Cys-OMe)2 and (Boc-Sec-OMe)2 , the disulfide exhibits a left-handed and the diselenide a right-handed orientation. Characterization of cystine and selenocystine derivatives in solution using 1 H-NMR, natural abundant 77 Se NMR, 2D-ROESY, and chemical shift analysis coupled to DMSO titration has indicated the symmetrical nature and antiparallel orientation of Cys/Sec residues about the disulfide/diselenide bridges. Structural calculations of cystine and selenocystine derivatives using DFT further support the antiparallel orientation of Cys/Sec residues about disulfide/diselenide. The far-ultraviolet (UV) region CD spectra of cystine and selenocystine derivatives have exhibited the negative Cotton effect (CE) for disulfide and positive for diselenide confirming the difference in the conformational preference of disulfide and diselenide. In the previously reported polymorphic structure of (Boc-Sec-OMe)2 , the diselenide has right-handed orientation. In the X-ray structures of disulfide and diselenide analogues of Escherichia coli protein encoded by curli specific gene C (CgsC) retrieved from Protein Databank (PDB), disulfide has left-handed and the diselenide right-handed orientation. The current report provides the evidence for the local conformational difference between a disulfide and a diselenide group under unconstrained conditions, which may be useful for the rational replacement of disulfide by diselenide in polypeptide chains.

Macrophages are abundant in the tumor microenvironment (TME), serving as accomplices to cancer cells for their invasion. Studies have explored the biochemical mechanisms that drive pro-tumor macrophage functions, however the role of TME interstitial flow (IF) is often disregarded. Therefore, we developed a three-dimensional microfluidic-based model with tumor cells and macrophages to study how IF affects macrophage migration and its potential contribution to cancer invasion. The presence of either tumor cells or IF individually increased macrophage migration directedness and speed. Interestingly, there was no additive effect on macrophage migration directedness and speed under the simultaneous presence of tumor cells and IF. Further, we present anin silicomodel that couples chemokine-mediated signaling with mechanosensing networks to explain ourin vitroobservations. The model proposes IL-8, CCL2 and β-integrin as key pathways that commonly regulate various Rho GTPases. In agreement,in vitromacrophage migration remained elevated when exposed to a saturating concentration of recombinant IL-8 or CCL2, or to the co-addition of a sub-optimal concentration of both cytokines. Moreover, antibody blockade against IL-8 and/or CCL2 inhibited migration that could be restored by IF, indicating cytokine-independent mechanisms of migration induction. Importantly, we demonstrate the utility of an integratedin silicoand 3Din vitroapproach to aid the design of tumor-associated macrophage-based immunotherapeutic strategies.