Role of Constituent Oxides for Thermal Mineralization of o-Dichloro Benzene over Mixed-Oxide-TiO2 Catalysts: A Mechanistic Explanation.

Catalysts with V2O5, WO3 and V2O5-WO3 dispersed over TiO2 were synthesized using sol-gel technique and thoroughly characterized by various techniques. The catalysts were evaluated for degradation of ortho-dichloro benzene (o-DCB) in air/helium, a representative probe molecule for polychlorinated dibenzo-para-dioxin and polychlorinated dibenzofuran by employing in situ Fourier-transform infrared spectroscopy (FT-IR spectroscopy). Different intermediate species formed on the surface of the TiO2 supported catalysts through of interaction of sorbate molecules with the lattice and/or gaseous oxygen were investigated in detail. Analysis of vibrational bands, observed during sorption of o-DCB and o-DCB-air mixture as a function of temperature over these catalysts, delineated the role of surface intermediate species such as phenolate, enolates, maleates, carboxylates, carbonates in mineralization of o-DCB. Nature and stability of intermediate species, found to be different over these catalysts, were able to elucidate the catalytic activity trend.

Solvated electron-induced synthesis of cyclodextrin-coated Pd nanoparticles: mechanistic, catalytic, and anticancer studies.

Herein, using in situ generated solvated electrons in the reaction media, a highly time-efficient, one-pot green approach has been employed to synthesize palladium (Pd) nanoparticles (NPs) coated with a molecular assembly of α-cyclodextrin (α-CD). The appearance of a shoulder peak at 280 nm in the UV-Vis absorption spectra indicated the formation of Pd NPs, which was further confirmed from their cubic phase XRD pattern. The nanomorphology varied considerably as a function of the dose rate, wherein sphere-shaped NPs (average size ∼ 7.6 nm) were formed in the case of high dose rate electron-beam assisted synthesis, while nanoflakes self-assembled to form nanoflower-shaped morphologies in a γ-ray mediated approach involving a low dose rate. The formation kinetics of NPs was investigated by pulse radiolysis which revealed the formation of Pd-based transients by the solvated electron-induced reaction. Importantly, no interference of α-CD was observed in the kinetics of the transient species, rather it played the role of a morphology directing agent in addition to a biocompatible stabilizing agent. The catalytic studies revealed that the morphology of the NPs has a significant effect on the reduction efficiency of 4-nitrophenol to 4-aminophenol. Another important highlight of this work is the demonstration of the morphology-dependent anticancer efficacy of Pd NPs against lung and brain cancer cells. Notably, flower-shaped Pd NPs exhibited significantly higher cancer cell killing as compared to spherical NPs, while being less toxic towards normal lung fibroblasts. Nonetheless, these findings show the promising potential of Pd NPs in anticancer treatment.

Rumen multi-omics addressing diet-host-microbiome interplay in farm animals: a review.

Continuous improvement in the living standards of developing countries, calls for an urgent need of high quality meat and dairy products. The farm animals have a micro-ecosystem in gastro-intestinal tract, comprising of a wide variety of flora and fauna which converts roughages and agricultural byproducts as well as nutrient rich concentrate sources into the useful products such as volatile fatty acids and microbial crude proteins. The microbial diversity changes according to composition of the feed, host species/breed and host's individual genetic makeup. From culture methods to next-generation sequencing technologies, the knowledge has emerged a lot to know-how of microbial world viz. their identification, enzymatic activities and metabolites which are the keys of ruminant's successful existence. The structural composition of ruminal community revealed through metagenomics can be elaborated by metatranscriptomics and metabolomics through deciphering their functional role in metabolism and their responses to the external and internal stimuli. These highly sophisticated analytical tools have made possible to correlate the differences in the feed efficiency, nutrients utilization and methane emissions to their rumen microbiome. The comprehensively understood rumen microbiome will enhance the knowledge in the fields of animal nutrition, biotechnology and climatology through deciphering the significance of each and every domain of residing microbial entity. The present review undertakes the recent investigations regarding rumen multi-omics viz. taxonomic and functional potential of microbial populations, host-diet-microbiome interactions and correlation with metabolic dynamics.

Durable PP/EPDM/GF/SiO2 nanocomposites with improved strength and toughness for orthotic applications.

Ankle-foot orthotics need ideal specification of being light-weight, high strength, tough, stiff, and durable. Reinforced polypropylene (PP) composites with enhanced mechanical properties are the most favorable materials being used in this field, but still, it is challenging to achieve balanced blend of strength and toughness in the composites. The present study thus aims to achieve the challenging task of simultaneous improvement in stiffness and toughness in reinforced PP composites exploring the synergistic reinforcement effect of glass fibers (GFs) and nano silica (SiO2) as multiscale fillers and ethylene propylene diene monomer (EPDM) as impact modifier. EPDM is used as toughness modifier, addressing the brittle behavior, but at the cost of the strength of the polymer. Combined use of micro and nanofillers as reinforcement in toughened polypropylene provides a potential approach to balance the strength while maintaining the toughness. GFs could offer high strength and nanofillers offer ductile fracture to the material. PP, PP/GF, PP/EPDM/GF composites and PP/EPDM/GF/SiO2 nanocomposites are fabricated through melt blending technique and are characterized through SEM, mechanical evaluation, nanoindentation and dynamic mechanical analysis. Mechanical properties are evaluated in accordance with ASTM standards. PP/EPDM/GF/SiO2 nanocomposites exhibits remarkable enhancement in Tensile strength, tensile modulus, impact strength and percent elongation at break by 49 MPa (55% increase over PP), 2450 MPa (145% increase), 145 J/m (13% increase) and 156% (160% increase) respectively. The exceptional improvement in reduced modulus and hardness reveals good interfacial properties. Loss factor decrement reveals elastic behavior of nanocomposites suitable for thermoforming of nanocomposites for orthotic device fabrication.

Synbiotic formulation of Cichorium intybus root powder with Lactobacillus acidophilus NCDC15 and Lactobacillus reuteri BFE7 improves growth performance in Murrah buffalo calves via altering selective gut health indices.

The objective of this study was to evaluate the effects of synbiotic formulation of Cichorium intybus root powder (C) with Lactobacillus acidophilus NCDC15 (LA) and Lactobacillus reuteri BFE7 (LR) on growth performance in Murrah buffalo calves via monitoring selective gut health indices. Twenty-four Murrah buffalo calves of 5-7 days old and 33 ± 2.0 kg of body weight were distributed randomly into three groups adopting complete randomized design (CRD) as follows: (1) group I served as control (CON) provided with a basal diet alone; (2) group II supplemented with synbiotic formulation of 200 mL L. acidophilus NCDC15 fermented milk with 8 g of Cichorium intybus root powder (LAC) along with basal diet; (3) group III supplemented with synbiotic formulation of 200 mL L. reuteri BFE7 fermented milk with 8 g of Cichorium intybus root powder (LRC) along with basal diet. The final body weight (BW), average dry matter intake (DMI) and structural body measurements were significantly increased (P < 0.05) in LAC and LRC groups by synbiotic as compared to the CON. No effect was registered on apparent nutrient digestibility coefficient of various nutrients in supplemented groups. Faecal score was reduced by the supplementation of synbiotic being lowest in LRC followed by LAC and CON. Calves supplemented synbiotic showed lower (P < 0.05) faecal pH and ammonia with a concomitant increase in faecal lactate levels and faecal short chain fatty acids (SCFA) as compared to control. The faecal Lactobacillus and Bifidobacterium population was increased (P < 0.05) in synbiotic fed groups as compared to control. Additionally, coliform and clostridia count was decreased (P < 0.05) in treatment groups compared to CON. Overall, it may be concluded that synbiotic supplementation was effective in improving the growth performance in Murrah buffalo calves via altering selective gut health indices.

Why Do Relative Intensities of Charge Transfer and Intra-4f Transitions of Eu3+ Ion Invert in Yttrium Germanate Hosts? Unravelling the Underlying Intricacies from Experimental and Theoretical Investigations.

The dominant intensity of parity-forbidden intra-4f transitions of europium(III) over O → Eu charge-transfer band (CTB) intensity is against common perceptions, yet this trend is observed in many germanate hosts and has not been rationalized so far. In search of a plausible explanation for this unusual trend, present work reports an experimental and theoretical investigations in conjunction on two sibling germanate host, namely, Y2GeO5 and Y2Ge2O7 having dopant Eu3+ in their respective YO7 polyhedra. Whereas for Y2GeO5:Eu3+, the CTB is more intense than the intra-4f transitions in the excitation spectrum, in the case of Y2Ge2O7:Eu3+, the relative intensities of CTB and intra-4f transitions are reversed. Comparative structural analysis reveals that Eu3+ present in YO7 of Y2GeO5 has a greater number of tetra-coordinated oxygen (Otetra) and yttrium atom as first and second neighbors, respectively (Eu3+-Otetra-Y3+ linkages). Conversely, in Y2Ge2O7 host, the Eu3+ ion mostly has tricoordinated oxygen (Otri) as its nearest neighbor and germanium ions next to Otri (Eu3+-Otri-Ge4+ linkage). Theoretical calculations reveal that while Y2GeO5:Eu has Otetra(4Y) dominating at the Fermi level and the 4f state of Eu3+ remains inert toward mixing, in Y2Ge2O7:Eu, the Fermi level has major contribution from Otri(2Y + 1Ge) with significant mixing with 4f states of Eu. The dominant control of Eu3+-Otri-Ge4+ linkages in geometrical and electronic structure of Y2Ge2O7:Eu owing to the GeO4 surrounding has been attributed to relative poor intensity of O → Eu CTB. Siege of Eu3+ by GeO4 and subsequent occurrence of Eu3+-Otri-Ge4+ linkages play a dual role: First, it induces electronic rigidity to hinder excitation of electron at bridging (Otri) oxygen by highly charged small Ge4+ cation; second, the covalent character in Eu-O bond is achieved by intermixing of Eu's 4f and Otri 2p orbital which facilitates relaxing of the parity-selection rule thus enhancing the probability of intra-4f transitions. The inferences drawn remain valid when extrapolated to other inorganic oxides having EuOx polyhedra surrounded by covalent units like PO4, SiO4, etc. and have a prevailing number of low-coordinated oxygen atoms and highly charged small cation in the first and second coordination shells, respectively. The optical basicity concept is also found to endorse our explanation. These remarkable generic inferences will pave the rational way for designing efficient phosphors for solid-state lighting.

Pancreatitis and hyperparathyroidism: Still a rare association!

BACKGROUND: Among the multitudinous etiologies of pancreatitis, primary hyperparathyroidism (PHPT) is rarely associated with pancreatitis. However, the cause and effect relationship between the two still evokes controversy. We aimed to study and characterize the nature of pancreatic disease in PHPT. METHODS: A retrospective single-center study was carried out in North India over a period of 1 year (June 2015 to May 2016). All patients with pancreatitis were included. In patients with high calcium levels, Intact Parathyroid Hormone (iPTH) by Radioimmunoassay (RIA) and an Technetium 99m Sestamibi scintigraphy (MIBI-Tc-99m) scan were performed. RESULTS: During the study period, 70 patients with pancreatitis were admitted to our hospital (53 with acute pancreatitis [AP] and 17 with chronic pancreatitis [CP]). Of them, 5 patients (9.4%) were detected to have PHPT. The mean age of patients was 30.4 years (20-49 years) with 3 males and 2 females, including 1 pregnant female (29th week of gestation). Contrast enhanced computed tomography (CECT) abdomen was performed in 4 cases (excluding 1 pregnant patient) with mean Computed tomography severity index (CTSI) of 4.7 (2-8). Four patients were detected to have increased uptake in one of the parathyroid glands, and the fifth patient had an ectopic parathyroid uptake in the mediastinum. All the resected samples were identified as parathyroid adenoma on histology. The patients were followed up for 1 year with no reported recurrence of symptoms. CONCLUSION: The data suggest an association between pancreatitis (both acute and chronic) and hypercalcemia due to PHPT. A high calcium value during AP or CP should always draw suspicion and warrants corresponding investigations in search of endocrine or malignant cause.

Effects of mannan-oligosaccharides and Lactobacillus acidophilus supplementation on growth performance, nutrient utilization and faecal characteristics in Murrah buffalo calves.

A study of 120 days was undertaken to ascertain the effect of mannan-oligosaccharides (MOS) and Lactobacillus acidophilus supplementation on growth performance, nutrient utilization and faecal characteristics in Murrah buffalo calves. Twenty Murrah buffalo calves of 5-7 days old and 31 ± 2.0 kg of body weight (BW) were randomly assigned into four groups. Group I served as the control (CON) in which only basal diet (concentrate mixture and green fodder) was provided, without any supplementation. Mannan-oligosaccharides at 4 g/calf/day were supplemented as prebiotic to Group II (PRE), whereas Group III (PRO) received Lactobacillus acidophilus in the form of fermented milk as probiotic at 200 ml/calf/day having 108  CFU/ml and Group IV (SYN) was supplemented with both MOS and Lactobacillus acidophilus as synbiotic at similar dose. Final BW (kg), dry matter intake, average daily gain, feed conversion efficiency and structural growth measurements were improved (p < .05) in the treatment groups compared to control. Digestibility of neutral detergent fibre was higher (p < .05) in SYN followed by PRE and PRO than control. The faecal lactobacilli and bifidobacterium population was higher (p < .05) in all the supplemented groups with a concomitant reduction in faecal coliform count as compared to control. Faecal ammonia, lactate and pH were also altered favourably (p < .05) in all the supplemented groups as compared to CON. The faecal volatile fatty acids were higher (p < .05) in PRE, PRO and SYN group than CON. The incorporation of MOS and Lactobacillus acidophilus in diet either individually or in combination as synbiotic has the potential to improve the performance and faecal characteristics in Murrah buffalo calves; however, the observed responses among the treatment groups were more evident in the synbiotic fed group compared to individual supplementation of MOS and Lactobacillus acidophilus.

High-pressure structural and vibrational properties of monazite-type BiPO4, LaPO4, CePO4, and PrPO4.

Monazite-type BiPO4, LaPO4, CePO4, and PrPO4 have been studied under high pressure by ab initio simulations and Raman spectroscopy measurements in the pressure range of stability of the monazite structure. A good agreement between experimental and theoretical Raman-active mode frequencies and pressure coefficients has been found which has allowed us to discuss the nature of the Raman-active modes. Besides, calculations have provided us with information on how the crystal structure is modified by pressure. This information has allowed us to determine the equation of state and the isothermal compressibility tensor of the four studied compounds. In addition, the information obtained on the polyhedral compressibility has been used to explain the anisotropic axial compressibility and the bulk compressibility of monazite phosphates. Finally, we have carried out a systematic discussion on the high-pressure behavior of the four studied phosphates in comparison to results of previous studies.

Optimization of lithium content in LiFePO4 for superior electrochemical performance: the role of impurities.

Carbon coated Li x FePO4 samples with systematically varying Li-content (x = 1, 1.02, 1.05, 1.10) have been synthesized via a sol-gel route. The Li : Fe ratios for the as-synthesized samples is found to vary from ∼0.96 : 1 to 1.16 : 1 as determined by the proton induced gamma emission (PIGE) technique (for Li) and ICP-OES (for Fe). According to Mössbauer spectroscopy, sample Li1.05FePO4 has the highest content (i.e., ∼91.5%) of the actual electroactive phase (viz., crystalline LiFePO4), followed by samples Li1.02FePO4, Li1.1FePO4 and LiFePO4; with the remaining content being primarily Fe-containing impurities, including a conducting FeP phase in samples Li1.02FePO4 and Li1.05FePO4. Electrodes based on sample Li1.05FePO4 show the best electrochemical performance in all aspects, retaining ∼150 mA h g-1 after 100 charge/discharge cycles at C/2, followed by sample Li1.02FePO4 (∼140 mA h g-1), LiFePO4 (∼120 mA h g-1) and Li1.10FePO4 (∼115 mA h g-1). Furthermore, the electrodes based on sample Li1.05FePO4 retain ∼107 mA h g-1 even at a high current density of 5C. Impedance spectra indicate that electrodes based on sample Li1.05FePO4 possess the least charge transfer resistance, plausibly having influence from the compositional aspects. This low charge transfer resistance is partially responsible for the superior electrochemical behavior of that specific composition.

Pre-operative neutrophil count and neutrophil-lymphocyte count ratio (NLCR) in predicting the histological grade of paediatric brain tumours: a preliminary study.

INTRODUCTION: The neutrophil-lymphocyte count ratio (NLCR) is an established prognostic marker for renal, lung and colorectal carcinomas and has been suggested to be predictive of histological grade and outcome in adult intracranial tumours. The purpose of this study was to determine whether a correlation of the pre-operative neutrophil count (NC) and NLCR with the final histological grade exists in paediatric intracranial tumours. METHODS: A retrospective analysis was undertaken at a single centre. Patients less than 18 years old at the time of surgery who underwent tumour-related procedures from 2006 to 2015 were included. Patients with recurrent tumours, previous bone marrow transplant and metastases were excluded. Pre-operative full blood counts (FBC), collected before the diagnosis of intracranial pathology and before administration of steroids, were matched with histological diagnosis for each patient. Post-operative FBC was also recorded, together with survival data where applicable. RESULTS: A total of 116 patients (74 male, 42 female; mean age, 8 ± 0.9 years) with a diagnosis of primary intracranial tumours had pre-operative FBC that could be matched to final histological grade. Pre-operative NC and NLCR were higher with increasing grade of tumour: grade 1 (NC 4.29 109/l, NLCR 2.26), grade 2 (NC 4.59 109/l, NLCR 2.38), grade 3 (NC 5.67 109/l, NLCR 2.72) and grade 4 (NC 6.59 109/l, NLCR 3.31). Patients with WHO grade 1 and 2 tumours pooled together had a lower NC (4.37 95% CI ± 0.67 109/l) compared to WHO grade 3 and 4 patients (6.41 95% CI ± 0.99 109/l, p = 0.0013). The NLCR was lower in grade 1 and 2 tumours (2.29 ± 0.59) (compared to grade 3 and 4 tumours; 3.20 ± 0.76) but this did not reach significance (p = 0.069). The subgroup of patients with pilocytic astrocytoma had a significantly lower NC when compared to patients with high-grade tumours (p = 0.005). Medulloblastoma and supratentorial PNET subgroups had significantly higher NC compared to the low-grade group (p = 0.033, p = 0.002). Post-operative NC was significantly higher in the high-grade tumours (p = 0.034), but no difference was observed for NLCR (p = 0.28). CONCLUSIONS: No evidence exists to support the correlation of pre-operative NC or NLCR to histological diagnosis in paediatric intracranial tumours. Our results indicate that a higher pre-operative NC/NLCR correlates with a higher histological grade of tumour. This suggests that immunological mechanisms may be involved in the pathogenesis of paediatric brain tumours, and a further prospective study is required to substantiate and expand these findings.

Revealing magnetic ordering and spin-phonon coupling in Y1-x Tb x MnO3 (0.1 ⩽ x ⩽ 0.3) compounds.

The structural and magnetic properties of the Y1-x Tb x MnO3 (0.1 ⩽ x ⩽ 0.3) compounds were investigated. Neutron diffraction patterns for all three samples, recorded at room temperature (RT), were fitted to the nuclear structure confirming the paramagnetic nature of the compounds. At 2.8 K, for the x = 0.1 sample magnetic moments of the Tb3+ ionic as well as Mn3+ ionic were ordered. At 5 K for the x = 0.2 sample only the Mn3+ ionic magnetic moments were ordered. There were six sites for Mn atoms. Three on the z = 0 plane and three on the z = 0.5 plane (where z corresponds to +c axis).The Mn3+ionic moments were confined to the a-b plane with a net magnitude of 2.78(3) µ B, and 2.90(3) µ B for the x = 0.1 and the x = 0.2 samples. The Tb3+ionic moments had a magnitude of 1.36(4) µ B at 2.8 K and were aligned antiferromagnetically along the crystallographic c-axis for the x = 0.1 sample. The low moment in comparison with Mn3+ free ions has been attributed to crystalline electric fields similar to that found in the parent compound YMnO3 and also in another rare earth manganite viz HoMnO3. The x = 0.3 sample was found to be a canonical spin glass. To investigate the role of the above spin ordering in Y1-x Tb x MnO3 in governing the phonon dynamics, temperature dependent Raman measurements were carried out. We observed the deviation of the phonon frequency near 685 cm-1 and its line-width from the expected anharmonic behaviour around magnetic ordering temperature for Tb substituted compounds with x = 0.1 and 0.2. This was attributed to the spin-phonon coupling in these systems. The anomalous behaviour of this phonon mode in the canonical spin glass compound with x = 0.3, indicated that the coupling sustained even in the presence of only local magnetic ordering.

Effect of omega-3 and omega-6 polyunsaturated fatty acid enriched diet on plasma IGF-1 and testosterone concentration, puberty and semen quality in male buffalo.

The objective of the present study was to evaluate the effect of omega-3 and omega-6 PUFA enriched diet on plasma IGF-1 and testosterone concentrations, puberty, sperm fatty acid profile and semen quality in male buffalo. Eighteen male buffalo calves were distributed randomly in three different groups and fed concentrate mixture along with green fodder and wheat straw in 50:40:10 ratios as per requirements. Basis ration of animals in group I was supplemented with 4% of prilled fat (PFA), while in group II and group III were added 4.67% of Calcium salt from Soybean (CaSFA) and Linseed oil (CaLFA), respectively. Male buffalo fed omega-3 PUFA high diet significantly increased concentrations of IGF-1 and testosterone in plasma as compared to two other diets (p<0.05). The age of puberty and scrotal circumference significantly increased by dietary fat effect (p<0.05) of which n-3 PUFA enriched diet (CaLFA) had the largest influence as compared to other diets (PFA and CaSFA). Feeding of n-3 PUFA rich diet significantly increased the DHA (C22:6n-3) content in sperm (p<0.05), which contributed to increased fluidity of plasma membrane, elevated quality of sperm (motility, viability) and in vitro fertility (plasma membrane integrity, acrosome integrity) in both fresh and post-thawing semen. These findings indicate that feeding of n-3 PUFA enriched diet increased IGF-1 and testosterone secretion, reduced pubertal age and improved both fresh and post-thawing semen quality in male buffalo.

Structural manipulation and tailoring of dielectric properties in SrTi1-xFexTaxO3 perovskites: Design of new lead free relaxors.

We report composition dependent structure evolution from SrTiO3 to SrFe0.5Ta0.5O3 by powder X-ray and neutron diffraction studies of SrTi1-2xFexTaxO3 (0.00 ≤ × ≤ 0.50) compositions. Structural studies reveal cubic (Pm3m) perovskite-type structure of the parent SrTiO3 for x up to 0.075 and cation disordered orthorhombic (Pbnm) perovskite-type structure for x ≥ 0.33. A biphasic region consisting of a mixture of cubic and orthorhombic structures is found in the range for 0.10 ≤ × ≤ 0.25. Dielectric studies reveal transformation from a normal dielectric to relaxor like properties with increasing Fe(3+) and Ta(5+) concentration. Dielectric response is maximum at x = 0.33 in the series. The results establish a protocol for designing new lead-free relaxor materials based on the co-substitution of Fe(3+) and Ta(5+) for Ti(4+) in SrTiO3. A complex interplay of strain effects arising from distribution of cations at the octahedral sites of the perovskite structure controls the dielectric properties.

A comparative study on defect estimation using XPS and Raman spectroscopy in few layer nanographitic structures.

Defects in planar and vertically oriented nanographitic structures (NGSs) synthesized by plasma enhanced chemical vapor deposition (PECVD) have been investigated using Raman and X-ray photoelectron spectroscopy. While Raman spectra reveal the dominance of vacancy and boundary type defects respectively in vertical and planar NGSs, XPS provides additional information on vacancy related defect peaks in the C 1s spectrum, which originate from non-conjugated carbon atoms in the hexagonal lattice. Although an excellent correlation prevails between these two techniques, our results show that estimation of surface defects by XPS is more accurate than Raman analysis. Nuances of these techniques are discussed in the context of assessing defects in nanographitic structures.

Pressure-induced phase transformation in zircon-type orthovanadate SmVO4 from experiment and theory.

The compression behavior of zircon-type samarium orthovanadate, SmVO4, has been investigated using synchrotron-based powder x-ray diffraction and ab initio calculations of up to 21 GPa. The results indicate the instability of ambient zircon phase at around 6 GPa, which transforms to a high-density scheelite-type phase. The high-pressure phase remains stable up to 21 GPa, the highest pressure reached in the present investigations. On pressure release, the scheelite phase is recovered. The crystal structure of the high-pressure phase and the equations of state for the zircon- and scheelite-type phases have been determined. Various compressibilities, such as the bulk, axial and bond compressibilities, estimated from the experimental data are found to be in good agreement with the results obtained from theoretical calculations. The calculated elastic constants show that the zircon structure becomes mechanically unstable beyond the transition pressure. Overall there is good agreement between the experimental and theoretical findings.

Energy efficient reduced graphene oxide additives: Mechanism of effective lubrication and antiwear properties.

Optimized concentration of reduced graphene oxide (rGO) in the lube is one of the important factors for effective lubrication of solid body contacts. At sufficiently lower concentration, the lubrication is ineffective and friction/wear is dominated by base oil. In contrast, at sufficiently higher concentration, the rGO sheets aggregates in the oil and weak interlayer sliding characteristic of graphene sheets is no more active for providing lubrication. However, at optimized concentration, friction coefficient and wear is remarkably reduced to 70% and 50%, respectively, as compared to neat oil. Traditionally, such lubrication is described by graphene/graphite particle deposited in contact surfaces that provides lower shear strength of boundary tribofilm. In the present investigation, graphene/graphite tribofilm was absent and existing traditional lubrication mechanism for the reduction of friction and wear is ruled out. It is demonstrated that effective lubrication is possible, if rGO is chemically linked with PEG molecules through hydrogen bonding and PEG intercalated graphene sheets provide sufficiently lower shear strength of freely suspended composite tribofilm under the contact pressure. The work revealed that physical deposition and adsorption of the graphene sheets in the metallic contacts is not necessary for the lubrication.

A chemical method for stabilizing a new series of solid solution Pr1-xCexScO3 (0.0 ≤x≤ 1.0) systems.

A new series of Pr1-xCexScO3 (0.0 ≤x≤ 1.0) compounds was synthesized by a two-step synthesis route, involving a combustion reaction followed by reduction while heating in a low partial pressure of O2, generated by a zirconium sponge that acts as an oxygen getter. For the first time, perovskite solid solution formation was observed in this series in the entire homogeneity range. These compounds were characterized using XRD, Raman spectroscopy and DRUV-visible spectroscopy. Rietveld refinement was carried out on the XRD data to determine unit cell parameters, bond lengths, bond angles along with the tilt angles for ScO6 octahedra. The analyses of the Raman shift were also in agreement with the XRD data. All compounds in this series showed a decreasing trend in the bandgap from 4.74 to 2.91 eV as a function of increasing Ce(3+) concentration.

Bifunctional Li and Co Doped ZnO Nanostructures Synthesized by Solvothermal Method: Stabilizer Controlled Shape and Size Tuning.

1D nanostructures of ZnO, Zn0.95Co0.05O and Zn0.85Co0.05Li0.10 were synthesized by a solvothermal chemical method with and without using oleic acid as a stabilizer. We report a very interesting observation of both room temperature ferromagnetism and photoluminescence properties along with development of different morphological transformation of these nanostructures on doping Co and Li in ZnO in the presence and absence of oleic acid. Zn0.95Co0.05O sample prepared in the presence of oleic acid showed increased saturation magnetization value (~ 4.1 emu/g and) compared to Zn0.95Co0.05O prepared without oleic acid (~ 1.1 emu/g). In both the cases it is observed that Li incorporation further enhances the room temperature ferromagnetic (RTFM) behavior and saturation magnetization values (~ 6 emu/g) of luminescent Zn0.95Co0.05 nanostructures. These results are significant, as the luminescent 1 D RTFM materials will have implications in photo magnetic devices like magneto-optical switches and sensors.