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A beam column junction is a key zone in a reinforced concrete moment resistant frame. It is exposed to a huge deal of stress throughout severe ground motion, and its performance has a noteworthy impact on the structure’s reaction if the ductility is inadequate, resulting in serious structural collapse. Use IS code 13920:1993 and provide ductile reinforcement according to ductile detailing of reinforcement beam column junction and ductile detailing of reinforcement beam column junction to improve the ductility of conventional beam column joints. The dimensions of the beam column junction are 700 mm*700 mm with a c/s of 200 mm*100 mm. The specimen will be cast in concrete to M30 specifications.

A lithium ion conducting solid biopolymer membrane (SBE) has been prepared by incorporating lithium chloride salt (LiCl) with the biopolymer K- Carrageenan (Kappa Carrageenan) using solution casting technique. One gram Kappa Carrageenan with 0.5 g LiCl yields ionic conductivity value of 1.15 × 10-2 Scm−1 which has been found by using Ac impedance analysis. The highest conducting biopolymer membrane possesses high amorphous nature among all the prepared biopolymer membranes, and XRD analysis confirms it. Highest conducting biopolymer possesses low crystallinity percentage of 8.18. Transference number analysis by Wagner’s polarization technique provides information that the major contribution for the conductivity is given by ions whereas minor contribution has been given by electrons. Transference number of ions is found to be 0.96 whereas transference number of electrons is 0.04. By using the using highest conducting composition (one gram Kappa Carrageenan: 0.5 g LiCl) as electrolyte, LiFePO4 as cathode and activated charcoal/graphite as anode, rechargeable lithium-ion conducting battery has been constructed and its voltage is found as 3.25 V. The performance of the battery has been studied by connecting a load (100 kΩ).

Diglycine Barium Chloride Monohydrate have been synthesized and characterized by the 13C and 1H NMR spectroscopy and single crystal X-ray structural studies with a detailed analysis of Hirshfeld surface and fingerprint plots facilitating the interactions within the crystal structure. The Protonated N H⋯O and intermolecular interaction responsible for the NLO activity are studied using DFT studies as well as experimental spectroscopic techniques. The molecular geometry, first & second hyperpolarizability studies and harmonic vibrational wavenumbers were calculated using density functional theory with B3LYP/SDD methods. The detailed interpretation of the vibrational spectra (FTIR and Raman) was carried out with the Normal Coordinate Analysis (NCA) following the scaled quantum mechanical force field methodology. The inter and intra molecular interactions responsible for the stabilization of the molecule were revealed by the NBO and AIM analyses. Photoluminescence spectrum shows that the luminescence is at the blue region. The observed saturable absorption and self-defocusing effect lead to optical limiting action at 532 nm for a CW diode-pumped Nd: YAG laser (50 mW) beam. Optical nonlinearity studies (z-scan) give the nonlinear refractive index, nonlinear absorption coefficient, third order nonlinear susceptibility, second order hyperpolarizability and optical limiting. The obtained results indicate that the synthesised compound is a good candidate for optical limiting and OLED applications.

A new salt, 4-aminopyridinium 3-(4-aminopyridinium) succinate tetra hydrate was synthesized from 4-aminopyridine and maleic acid in 2:1 stoichiometric ratio. The salt was characterised using single crystal X-ray diffraction, Raman scattering and DSC/DTA techniques. Intermolecular interactions in the salt investigated through Hirshfeld surfaces and 2D finger plots, showed that the C..H, N..H, O..H and H…H interactions were 15.4%, 2.2%,37.6% and 41.3% respectively. The water molecules occupy around 19.2% of the total volume of the unit cell and also contribute significantly to the stability of the crystal. As the salt crystallizes in a non-centerosymmetric space group, it can exhibit second order non-linear optical properties. MOPAC was used to calculate the hyperpolarizability, it was found to be 3.29378 10−30 esu. A database analysis to compare the bond parameters and the physical properties like hyperpolarizability etc. in 4-aminopyridine and its complexes was undertaken. It was found that, in general, complexation or salt formation leads to higher average polarizability, hyperpolarizability and dipole moment, and our salt also has higher hyperpolarizablilty than that of parent compound 4-aminopyridine.

l -histidine tetra fluroborate (L-HTFB) is a semi-organic NLO material. Ab-initio computations were performed at CAM-B3LYP/ 6–311++g(d,p) level of theory to arrive at the structures, energies, and vibrational wave numbers. The experimental FT-IR and FT-Raman spectra of L-HTFB have been recorded and analyzed. It is compared with the simulated spectra. The scaled wave numbers obtained are in good agreement with the experimental values. Hirshfeld surface analysis represented in the 2D fingerprint plot reveals the interaction within the compound. Optimized geometry reveals that the complexes l -histidine (L-H) and tetrafluoroborate (TFB) are linked by H-F bond which provides inter and intra molecular hydrogen bonded interactions such as N10-H16⋯F25, N11-H17⋯F22, N11-H14⋯F24, N11-H14⋯N10 and N11-H15⋯O12. The inter-molecular distances H17⋯F22, H14⋯F24 and H16⋯F25 are in between 1.82 A and 2.53 A. The intra molecular distances H14⋯N10 and H15⋯O12 are found to be at 2.17 A and 1.71 A which stabilizes lone pair electron of N10 and O12 with energies 11.89 and 59.91 KJ/mol respectively. The intra and inter molecular hyperconjugations responsible for the stability of the molecule are well identified theoretically using the NBO analysis. Third order optical nonlinearity is measured by means of the open aperture Z-scan technique which reveals that the crystal has optical limiting property. Photoluminescence results clearly indicate the use of L-HTFB as a new violet-light emitting material.

Single crystal neutron diffraction investigation [Choudhury and Chitra, J. Phys. Condense Matter, 25 (2013) 075902] on four mixed crystals with composition (K1−x(NH4)xH2PO4) where x=0.0, 0.29, 0.67, and 1.0 belonging to the potassium dihydrogen phosphate family of hydrogen bonded ferroelectric crystals had revealed that the compositional variation results in subtle structural differences primarily in the hydrogen bonds of these crystals. The study indicated that there is a change in hydrogen bond strengths with the change in crystal composition. Spectral investigation of the same set of four mixed crystals is undertaken with an intention to study the influence of the varying hydrogen bond strength on the vibrational properties of the crystals. Room temperature Raman spectra for all the four crystals are recorded in the range 100–4000 cm−1. This Raman investigation correlates the structural changes observed from neutron diffraction investigations to the changes in the vibration spectra of the crystals. The varying N–H–O hydrogen bond strength in the mixed crystals is found to have an observable effect on the librational frequencies of the molecular components of these crystals. The strong OHO hydrogen bonds in these crystals give rise to four spectral bands in the 1500–3000 cm−1 spectral region; this is in accordance with the theoretical prediction from the tunneling model for the very strong OHO hydrogen bonds. These OHO bonds can be described by a low barrier double well potential; the vibrational energy levels of the potential are split due to quantum tunneling effects. It is observed that the varying OHO hydrogen bond strength of these crystals results in a variation in the splitting of the vibrational energy levels of the hydrogen bond potential. It is attempted to correlate the varying OHO hydrogen bond strength with the expected variation in the freezing temperature with composition of these proton glasses.

A new third order nonlinear optical single crystal of Morpholin-4-ium hydrogen tartrate has been grown by the slow evaporation method. The lattice parameters and crystalline purity of this orthorhombic crystal were measured by single crystal X-ray diffraction and powder X-diffraction technique respectively. The optimized geometry shows that the morpholinium ring exist in a chair form where tartrate anions are linked via N H⋯O hydrogen bonds, forming chains. These chains are linked via N H⋯O and O H⋯O hydrogen bonds, involving the morpholinium cation. The vibrational spectral investigation predicts that the red shifting of O H and N H stretching wavenumbers are due to O H⋯O and N H⋯O intermolecular interactions, respectively which are also evident form NBO analysis. The photoluminescence spectrum shows luminescence at the blue region with an appreciable lifetime leading to applications in blue OLEDs. Third order nonlinear optical properties like self-defocusing, saturable absorption and optical limiting at 532 nm are identified by Z-scan analysis. The laser damage threshold (LDT) energy have been measured by using Nd:YAG laser of wavelength 532 nm. The field dependent nature of first and second order hyperpolarizabilities and luminescence properties suggest that MHT crystal is a potential candidate for OLED and nonlinear optical applications.

We report here the results of our high pressure infrared absorption investigations on Bis(glycinium)oxalate, an organic complex of glycine. The observation of Raman active modes in the IR spectra beyond 1.6 GPa indicates the emergence of a non centrosymmetric high pressure phase. The pressure induced changes in the infrared active modes also indicate another structural transformation above 4.5 GPa. High pressure behavior of OH stretching mode of this compound has been studied to obtain the information about O–H⋯O hydrogen bond at higher pressures.

Crystals of a new salt in 2:1 ratio of 2-aminopyridine and malonic acid are grown by slow evaporation. These crystals of bis(2-aminopyridinium) malonate are orthorhombic and belong to the non-centrosymmetric space group, Fdd2 with parameters a = 22.0786(6), b = 23.0218(6), c = 5.5595(1)angstrom and Z=8 at 300 K. The crystals are isostructural to those of bis(2-aminopyridinium) maleate, which is a NLO material. The isostructurality index between bis(2-aminopyridinium) maleate and bis(2-aminopyridinium) malonate was also calculated. The hyperpolarizability calculated using semi empirical method MOPAC2009 showed that bis(2-aminopyridinium) malonate has slightly higher beta value compared to that of bis(2-aminopyridinium) maleate. (C) 2011 Elsevier B.V. All rights reserved.

This paper proposes reduction of energy losses in low voltage distribution network using Lab VIEW as simulation tool. It suggests a methodology for balancing load in all three phases by predicting and controlling current unbalance in three phase distribution systems by node reconfiguration solution for typical Indian scenario. A fuzzy logic based load balancing technique along with optimization oriented expert system for implementing the load changing decision is proposed. The input is the total phase current for each of the three phases. The average unbalance per phase is calculated and checked against threshold value. If the average unbalance per phase is below threshold value, the system is balanced. Otherwise, it goes for the fuzzy logic based load balancing. The output from the fuzzy logic based load balancing is the value of load to be changed for each phase. A negative value indicates that the specific phase is less loaded and should receive the load, while a positive value indicates that the specific phase is surplus load and should release that amount of load. The load change configuration is the input to the expert system which suggests optimal shifting of the specific number of load points, i.e., the consumers.

The structural investigation of the ferroelectric phase transition in glycine silver nitrate has revealed that the transition at T c = 218 K is due to the displacement of the Ag+ ions from the plane made by the carboxyl oxygens of glycine zwitterions coordinated to it. Since the transition takes place between two ordered structures the thermal anomaly at T c is very weak, the transition enthalpy and transition entropy were found to be Δ H = 6.6 J / mol and the transition entropy Δ S = 0.03 J K − 1 mol − 1 respectively. These crystals are held together by a network of hydrogen bonds. In order to study these interactions the Raman spectrum of GSN was recorded and discussed in the light of ferroelectricity in glycine complexes in general.

A quantitative estimate of dipolar interaction energy causing the order–disorder ferroelectric phase transition in triglycine sulphate (TGS) is obtained and also the effect of small hydrostatic pressures on the dipolar energy is modelled. At high pressures of the order of 2.5 GPa a crystallographic phase transition to a non-ferroelectric phase takes place in these crystals, the spontaneous polarization goes to zero most likely because of the glycine ion GI becoming planar at high pressures. The inverse Ubbelohde effect observed in TGS is successfully explained using the corrected valence bond model. The increase in transition temperature (TC) on deuteration is associated with the increase in value of the reorientable dipole moment of TGS. A quantitative estimate of increase is obtained using the Mecke dipole function.

Metal-semiconductor multilayers are interesting, artificial structures as prospective candidates for spin injection devices. A Fe–Ge multilayer sample with very thin individual layers (few crystallographic planes) has been deposited by sputtering on Si[1 0 0] substrate. We have characterized the structure of this multilayer sample using X-ray diffraction, X-ray reflectometry and neutron reflectometry. The magnetic moment density in the ferromagnetic Fe layer has been obtained by polarized neutron reflectometry and the bulk magnetic behavior of the thin film by SQUID magnetometer measurements. We found that the film is a soft ferromagnet at room temperature with a substantially reduced magnetic moment of the Fe atoms.

Properties of the monolayer of octadecyl amine (ODA) molecules on aqueous solution of bromocresol purple (Bcp) dye have been studied over a wide range of pH by measuring the surface pressure-area isotherms. A strong interaction of ODA molecule was observed with the dye molecule in the pH range of 4–9. Under the present study, the dye molecules were adsorbed on the ODA monolayer at the water surface and subsequently a Langmuir–Blodgett (LB) film of ODA–dye complex was transferred from the air–water interface onto a solid substrate. Alternatively, dye molecules were incorporated into LB film by immersing the predeposited LB film of pure ODA into the dye solution, i.e. by adsorption of dye molecule at the solid–liquid interface. The adsorption behavior of ODA–Bcp dye complexes obtained through these two different routes was characterised with the help of UV–Visible spectroscopy. The nature of the ODA–dye complex deposited from air–water interface using the LB technique was found to be quite different from that of the complex formed by the adsorption of the dye into the pure ODA LB film. The adsorption spectra of the ODA–dye complex obtained from the air–water interface did not change with pH, while those of the ODA–dye complex formed from the solid–liquid interface showed pH dependence.

A series of lanthanide oxides was incorporated in a vitreous phosphate host network. Molar constituents of the glasses were typically (La2O3)10(RxOy)10(Al2O3)5(P2O5)75. Each glass had a different lanthanide (R atom) from the series; La, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er and the values of x and y depended on the valency of the rare-earth atom. Both X-ray and neutron diffraction were employed in examining their structures. The results indicate that the basic PO4 tetrahedral unit remains unaltered with an average P–O distance of 1.54±0.02 A and predominant Q2 linkages to its neighbouring units so as to form a continuous network while accommodating the included lanthanides. In accordance with this model, the average distance of rare-earth (comprising La and a second type of R atom) to oxygen decreased from 2.44 to 2.26 A, a trend to be expected from the lanthanide contraction. The average oxygen coordination around the rare-earth was found to vary in the range of 6–8. With these average parameters, a small (74 atom) hand-built model was made to check the feasibility of constructing a continuous random network. Optical transmission measurements show all these glasses to absorb strongly in the UV region and to have marked absorption resonances in the visible region of 400–1000 nm except for the La, Ce, Eu, Tb containing glasses which have low or negligible absorption in the latter range.

The studies on ion transport of terbium and dysprosium through a porous supported liquid membrane (SLM) containing TOPO (trioctyl phosphine oxide) and TBP (tributyl phosphate) as immobilised carriers have been carried out. The effect of stirring of bulk solutions on permeability coefficient has been investigated. The permeability coefficient increases with increase in pH of source phase from 0–6, and hydrogen ion concentration from 0.01 to 0.1 M of receiving solution. The dependency of permeability coefficient on the carrier concentration has been explored. The effect of ammonium thiocyanate concentration on permeability coefficient has been studied. In order to develop a method for enrichment of rare earth elements, further investigations were carried out by using a hollow fibre membrane extractor. The mechanism of ion transport of terbium and dysprosium in SLM systems has been explained.

Kinetic studies of yttrium recovery, consisting of extraction and stripping processes have made using 2-ethylhexyl-phosphonic acid mono-2-ethylhexyl ester (PC-88A, EHPNA) as an acidic extractant. The experimental variables affecting the ion transport flux of yttrium have been explored; that is, pH, carrier and stripping agent concentrations. Kinetic models for the extraction and stripping processes, including the complexation mechanism, are proposed.

A Monte Carlo simulation of a thirteen-atom argon cluster in supercages of zeolite NaCaA is reported. The confined cluster undergoes distortion giving a peak in the angle distribution function at around 90°. The structure, energetics and other properties are dictated by a competition between guest-guest and guest-zeolite interactions. It is found that the cluster melts in the region from 25 to 40 K. The change in δ during melting is smaller than that observed for bulk matter or that for the free cluster, which we attribute to confinement.

Studies on the kinetics of neodymium transport through a bulk liquid membrane, in apparatus consisting of a source, membrane and receiving phases, have been carried out. Different experimental variables, such as the pH, carrier, metal ion and stripping agent concentrations, have been explored. However, the kinetic and solvent extraction methods were compared to determine the equilibrium extraction constant. Complexation mechanism models have been developed. The kinetic behaviour of the ion transport based on forward and backward extraction processes with the consideration of controlled parameters was predicted. The ion transport of neodymium in the receiving or membrane phase envisages the determination of forward and backward extraction rate constants.

Diffusion coefficients $D_1$ and $D_2$ of a binary mixture of adsorbates of diameters $\sigma_1$ and $\sigma_2$ in the restricted regions of zeolite NaY have been obtained from molecular dynamics simulations. The results suggest that the ratio of the diffusion coefficients $\zeta=D_1/D_2$ exhibit unusual behaviour with an increase in the ratio of diameters $\eta=\sigma_1/\sigma_2:D_1>D_2$ even when $\sigma_1>\sigma_2$. Calculations on a single component adsorbate in zeolite NaY suggest that the diffusion coefficient shows an anomaly when the adsorbate diameter approaches the diameter of the window, the narrowest portion of the porous network. It is shown that the latter result explains the unexpected behaviour in the ratio of diffusion coefficients observed for the binary mixture.

Trypsin inhibitor activity (TIA), water-soluble protein and total protein contents varied markedly among the twenty cultivars of Black Gram grains assayed. Although no relationship could be established between TIA and total protein content, significant positive correlation was seen between TIA and water-soluble protein. During the ontogeny of seed, the TIA and water-soluble protein increased gradually. However, during germination, TIA was found to decrease up to 48 h and this was followed by a sharp increase.