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Present study focuses on the development of sustainable green-sourced carbon nano-sphere (CNSp) from Betel Leaf by thermal decomposition method for high-performance Polyurethane coating. The obtained carbon black was then functionalized with acid solution. FTIR analysis confirms the presence of carboxyl group. The graphitic domain present in the nano-sphere were found using XRD and Raman spectroscopy. TEM analysis clearly shows the mono-dispersed sized nano-spheres of about ~ 40 nm. The nano-sphere was further incorporated into castor oil based Polyurethane coatings. The nanoscale incorporation of the CNSp (0.2 and 0.5%) into the PU shows good increment in the resultant mechanical and thermo-mechanical properties of the polyurethane/carbon nano-sphere hybrid in comparison to the virgin PU film. The DMTA result shows an increase in the storage modulus from 3730 to 4454 MPa. Moreover, an accretion in the tensile strength was observed from 5.55 to 9.77 MPa Overall increments of 76.03% and good surface roughness observed by SEM analysis. [ABSTRACT FROM AUTHOR]

Polybenzoxazine (PBz)/BMI/reduced graphene oxide (rGO) nanocomposites were prepared by varying the weight percentage of rGO from 1 to 5 wt%. The exfoliated sheet morphology of rGO makes it well-dispersed in the PBz/BMI matrix. The curing process monitored by DSC analysis showed two exothermic curves. Of which one is due to the reaction between BMI and furan ring and the other due to ring-opening polymerization. The nanocomposites did not show any agglomeration even at higher loadings (5 wt%) of rGO nanofillers. The degree of dispersion of rGO nanofillers resulted in enhancement of mechanical and thermal properties of PBz/BMI/rGO nanocomposites. A very low percentage of the nanofillers of about 5 wt% could tremendously increase the thermal stability, storage modulus and dielectric properties of the nanocomposites. [ABSTRACT FROM AUTHOR]

Two-stage fibre-reinforced concrete (TSFRC) is a novel fibrous concrete that differs from the conventional fibre-reinforced concrete (FRC) in several aspects including its placement technique, implementation, fabrication methodology, and high coarse aggregate content. Consequently, the available data from the open literature on the behaviour of the conventional FRC exposed to falling weight collision may not be applicable to TSFRC. For instance, the impact strength performance of the conventional FRC is well documented; however, for TSFRC this has not been duly examined. For the first time, this study pioneers the concept of impact strength of TSFRC under falling weight collision. For this purpose, short crimped fibres and long hooked end steel fibres at 1.5, 3.0, and 5.0% dosage were used in two-stage concrete (TSC). To this end, seven different mixes were prepared and tested under falling weight collision as per ACI committee 544. In addition, a statistical analysis has been performed to analyse the scattered test results by Weibull distribution. For determining Weibull parameters, 20 probability estimators have been used, and the best estimators are taken for the reliability analysis. Based on the obtained Weibull parameters, the impact strength of TSFRC has been reported in terms of reliability. The results revealed that the ability of using higher fibre dosages allows achieving greater impact resistance properties for novel manufacturing TSFRC. Indeed, the TSC with steel fibre dosages exceeding 5%, can be produced easily thus making this innovative, yet simple to produce concrete, a strong contender in many construction applications. The two-parameter Weibull theory has been found to be adequately suitable for analysing the variations in the number of impacts that induces first crack and failure of all group of TSFRC specimens. [ABSTRACT FROM AUTHOR]

The variations in impact strength of steel Fibre Reinforced Concrete (FRC) were statistically, commanded in this research. For this purpose, the experimental impact test results of earlier researchers were investigated using two statistical approaches. Firstly, normality test was carried out on first crack strength (N1) and failure strength (N2) using distribution plot and its accuracy was verified with Kolmogorov-Smirnov, Shapiro-Wilk and Chen-Shapiro test. Secondly, strength reliability analysis was carried out using two parameter Weibull distribution and their Weibull parameters were determined using three methods viz., Empherical Method of Justus (EMJ), Method of Moments (MOM) and Empherical Method of Lysen (EML). Results suggested that, if three samples are used to determine the N1 value for researchers' data, at 95% levels of confidence, then the error in the measured value is about 50%. The 0.1 reliability level of the impact strength values of EMJ, EML and MOM were 153, 120 and 153 respectively in case of N1 and were 198, 156, and 198 respectively in case of N2 based on earlier researcher's data. [ABSTRACT FROM AUTHOR]

Non-precious metal electrocatalysts obtained by pyrolysis of precursors of metal, nitrogen, and carbon (MNC) are viewed as an inexpensive replacement for platinum-based electrocatalysts for the oxygen reduction reaction (ORR) in fuel cells. The hypothesized ORR active site structure of typical MNC catalysts consists of a transition metal coordinated to the pyridinic/pyrollic type of nitrogen covalently attached to the edges of the graphitic crystallites. One of the drawbacks of all the reported procedures to synthesize these MNC electrocatalysts is the inability to control the formation of a specific active site structure suitable for ORR. Lack of clarity on the active site structure limits the researcher's ability to design a synthesis methodology that maximizes the specific active site density. In this study, we have synthesized a Co(III) dimer ([Co(OH)(OOCCH)(bpy)] NO ⋅ 1.5 H O) and demonstrated its ORR activity in alkaline medium. The ORR activity and methanol tolerance property of the Co(III) dimer were compared with those of Ketjenblack carbon (used as support for Co(III) dimer) and commercial 20 wt% Pt/C, respectively. Since Co(III) dimer is a molecular material, its characterization by single-crystal X-ray diffraction, nuclear magnetic resonance, and infrared studies revealed the chemical structure unambiguously. Density functional theory calculation predicted the possibility of both end-on and side-on oxygen adsorption at the metal center of the Co(III) dimer. [ABSTRACT FROM AUTHOR]

Purpose: Although a substantial proportion of patients with heart failure (HF) have anemia, there is a paucity of data evaluating the impact of anemia on clinical outcome in CRT patients. Our goal was to examine the ability of baseline hemoglobin (Hb) level and change in Hb level over time to predict clinical 2-year outcome and echocardiographic response to CRT.Methods: Three hundred consecutive CRT patients (median 72 years [interquartile range (IQR) 16 years], 19% female) with baseline and follow-up hematological profiles available were examined. Baseline anemia was defined as Hb <12 g/dL in women and <13 g/dL in men, and patients were grouped into equal quartiles based on change in Hb. Two-year clinical outcome was determined using a composite endpoint that included HF hospitalization, left ventricular assist device (LVAD) placement, heart transplantation, and all-cause mortality. Echocardiographic reverse remodeling was examined at 6-month follow-up.Results: One hundred fifty-one anemic patients were compared to 149 non-anemic patients. Changes in left ventricular dimensions and ejection fraction were similar for both groups. Univariate predictors of 2-year clinical outcome included baseline creatinine level, diuretic usage, and anemia; in multivariable regression, baseline anemia was an independent predictor for outcome (hazard ratio [HR] 1.79, 95% confidence interval [CI] [1.22-2.63], p = 0.003). The quartile with the most negative change in Hb concentration over time (≤-1.00 g/dL) had poorer event-free 2-year survival (HR 1.84, CI [1.13-3.00], p = 0.014).Conclusions: Baseline anemia and early postimplantation decline in Hb levels are associated with a worse 2-year prognosis in CRT patients, even though the magnitude of left ventricular reverse remodeling is similar compared to non-anemic patients. [ABSTRACT FROM AUTHOR]

The present study was undertaken to investigate the diversity of mangrove-associated bacterial genera at Manakudy estuary, Southwest coast of India. The root and rhizosphere sediments of both mangrove and their associated plants were collected from chosen area. Results inferred that the maximum nutrients, THB density, and diversity indices were recorded in rhizosphere and root sample of Avicennia officinalis. Altogether, 258 bacterial strains were isolated from the chosen mangrove samples and screened for nitrogen fixing and phosphate solubilizing ability. Screened result inferred that, 36.43 % isolates had nitrogen fixing and 29.45 % isolates had phosphate solubilizing ability. Here, the genus Bacillus spp. (21.71 %) was the most dominant genera. The bacterial diversity indices, i.e., univariate analysis showed remarkable variation between the chosen samples; however, maximum diversity indices was registered by rhizosphere and root sample of A. officinalis. The 95 % confidence interval and ellipse showed that samples were well mendacious within AvTD and VarTD. Likewise, the multivariate analysis like similarity percentage was good discriminator from 16.64 to 100 % by Bray-Curtis dissimilarity. The prinicipal component analysis (PCA) showed marked variation between the tested bacterial communities. Cluster analysis and non-metric multi-dimensional scaling (MDS) were grouped by Bray-Curtis similarity index which strongly evidence that the rhizosphere and root samples of A. officinalis were highly diversified in the study area. [ABSTRACT FROM AUTHOR]

Self-assembled molecular triangles [Pd(phen)(imidazolate)](NO), 1a and [Pd(phen) (imidazolate)](PF), 1b are prepared by the combination of imidazole with Pd(phen)(NO) and Pd(phen) (PF), respectively. Imidazole was deprotonated during the complexation reactions and the imidazolate so formed acted as a bis-monodentate bridging ligand to form the bowl-shaped trinuclear architectures of 1a/b. Relative orientation of the imidazolate moieties can be best described as syn,anti,antias observed in the crystal structure of 1b. However, in solution state, slow conformational changes are assumed on the basis of HNMR spectral data. The molecular triangles are crafted with three peripheral phen units capable of π− π stacking interactions. Well-fashioned intermolecular π− π interactions are observed in the solid-state, wherein further self-assembly of already self-assembled triangle is observed. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A rare variety of self-assembled molecular triangle [Pd(bpy)(imidazolate)](NO), 1 is prepared by the combination of Pd(bpy)(NO) with imidazole, at 1:1 ratio, in acetonitrile-water. Deprotonation of imidazole happened during the course of the complexation reaction where upon the metallomacrocycle is formed. The bowl-shaped trinuclear architecture of 1 is crafted with three peripheral bpy units capable of π− π stacking interactions. While the solution state structure of 1can be best described as a trinuclear complex, in the solid-state well-fashioned intermolecular π− π and CH- π interactions are observed. Thus, in the solid-state further self-assembly of already self-assembled molecular triangle is witnessed. The triangular panels are arranged in a linear manner utilizing intermolecular π− π interactions where upon two out of three bpy units of each molecule participated in the chain formation. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A new mannich base 1-(morpholino(phenyl)methyl)pyrrolidine-2,5-dione formed by the direct condensation of morpholine, succinimide and benzaldehyde has been synthesized. The structure of this mannich base has been elucidated on the basis of micro elemental analysis, IR, 1H NMR, 13C NMR, UV–Visible Techniques and Mass. The crystal structure of the title compound C15 H18 N2 O3 was determined. It crystallizes in the triclinic system, space group P − 1, with a = 8.8122(13) Å, b = 9.2794(14) Å, c = 9.814 (3) Å, α = 107.154(9)°, β = 97.936(9)°, γ = 110.197(7)°, V = 693.4(2) Å3, D x = 1.314 Mg/m3. The structure was solved by the full-matrix least squares on F2 and had a refined R value of 0.0486 for 8567 observed reflections. The six membered heterocyclic ring of the morpholino moiety adopts a chair conformation. The crystal structure is stabilized by weak intermolecular C–H···O interactions that link the molecules into inversion dimers. This paper describes the spectroscopic and crystallographic studies of the title compound which is essential in ascertaining the structure of this new compound. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In this paper the machine layout problem with a linear single-row flow path in automated manufacturing systems is investigated. Traditional machine layout approaches can produce an inappropriate layout design because they often do not consider flow path characteristics, such as flow path configuration and feasible flow path direction. This paper investigates the effects of such flow path characteristics on machine layouts. There are six flow-line analysis methods reported in the literature. Of these, the two best methods (FLA-5 for bidirectional flow lines and FLA-6 for unidirectional flow lines) are considered here. Two heuristic search algorithms, one combining FLA-5 and a genetic algorithm and other combining FLA-6 and a genetic algorithm, are proposed. A wide variety of data sets are used to test the proposed algorithms. [ABSTRACT FROM AUTHOR]