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In this work, ammonia intercalated zinc hydroxide chloride hydrate (ZHC-NH3), Zn5(OH)8Cl2.4[(H2O)x(NH3)1-x)] was synthesised using precursor, [ZnCl2.2{HONC(CH3)2}] by sol-gel method in presence of ammonia and characterised by FT-IR, SEM-EDX, and XRD analysis. On sintering at 500°C, ZHC-NH3 transformed to ZnO nanoparticles (ZnO NPs) as confirmed by the XRD patterns. ZHC-NH3 has nanoplates-like morphology with a positive surface charge (+28.8 mV) while synthesised ZnO nanoparticles (ZnO-NPs) have spherical morphologies with negative surface charge (−8.28 mV). Band gap of 2.7 eV was observed in ZHC-NH3 while in ZnO NPs it was obtained as 3.3 eV. A comparison has been done on the photocatalytic activities of ZHC-NH3 and ZnO NPs towards the degradation of methylene blue (cationic dye) and methyl orange (anionic dye) under sunlight and it was found that photo-degradation of anionic dye, methyl orange is superior (96.28%) in presence of ZHC-NH3 photocatalyst as compared to ZnO photocatalyst (55.42%). The adsorption capacities of ZHC-NH3 towards Pb2+, Cd2+, and Cr3+ heavy metal ions were found 47.00 mg. g−1, 20.40 mg. g−1, and 48.85 mg. g−1 whereas ZnO-NPs have adsorptions capacities of 46.97 mg. g−1, 43.07 mg. g−1, 29.21 mg. g−1, for Pb2+, Cd2+, and Cr3+ heavy metal ions, respectively. [ABSTRACT FROM AUTHOR]

The thermoluminescence material, CaSO 4 :Dy, is widely used for the dosimetry of ionizing radiation due to its high sensitivity, low fading and wide dose range from μGy to few tens of gray. However, its application is limited at high doses due to non-linear and saturation effects. In this paper, X-ray Absorption Near Edge Structure (XANES) studies at the Dy L 3 -edge have been carried out on CaSO 4 :Dy discs exposed to gamma doses in the range 0–1000 Gy. The results show an increase in white line in XANES spectra with gamma dose. Structural change in CaSO 4 :Dy also has been studied using X-Ray Diffraction (XRD) and has found no structural change up to 1000 Gy. The study indicates that XANES can be used as an alternative dosimetry technique and is useful in the evaluation of absorbed dose in the case of accidental exposure to high radiation in a radiation facility or during a radiological accident. • XANES gives a direct evidence of Dy3+ transition to Dy2+ on gamma irradiation of CaSO 4 :Dy. • Area under XANES spectrum is found to increase linearly with absorbed dose. • XANES is proposed as a potential dosimetry technique in high dose exposure. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a maiden alternative approach to the cost based allocation over the transmission network for individual generators associated with the system. A modified method is proposed by which the proportion of power going from an individual generator to the loads, and to the rest of the transmission network can be traced in a grid system. Also, the revenue collected from the customer side for all associated producers separately can be determined. The developed technique has been experimented successfully on a 39-bus New England Power System and to validate the method, the outcomes of the projected algorithm of the test system are compared with the power flow solution obtained by using the sequential quadratic programming method. The comparative analysis reveals that the results obtained from both the methods are nearly the same under different loading conditions, proving the accuracy and robustness of the proposed method. [ABSTRACT FROM AUTHOR]

Structural, magnetic and electronic properties of partially inverted Cobalt Ferrite with composition Co 1.5 Fe 1.5 O 4 is discussed in the present work. Single phase (SG: Fd3m) sample is synthesized by co-precipitation technique and subsequent air annealing. The values of saturation magnetization obtained from careful analysis of approach to saturation in initial M(H) curves are used to determine spin states of Co ions in tetrahedral (T H ) and octahedral (O H ) sites. Spin states of Co 3+ ions in T H sites, which has not been reported in literature, were found to be in high spin state. Temperature variation of magnetic parameters has been studied. The sample shows magneto-crystalline anisotropy with two clearly distinct pinning centers. Oxygen K-edge and Fe as well as Co L 2,3 -edge X-ray absorption (XAS) spectra have been used as complementary measurements to study crystal field splitting and core hole effects on transition metal (TM) 3d orbitals. The ratio of intensities of t 2g and e g absorption bands in O-K edge XAS spectrum is used to estimate the spin states of Co ions at O H and T H sites. The results are in agreement with those obtained from magnetization data, and favors Co 3+ ions in T H sites in high spin states. Normalized areas of the satellite peaks in TM L 2 , 3 -edge XAS spectra have been used to estimate 3d n+1 L contribution in ground state wave function and the contributions were found to be significant. [ABSTRACT FROM AUTHOR]

In this study, we synthesized Pd-graphene oxide (Pd-GO) nanocomposite layers on SiO 2 /Si substrates using chemical method. Pd-GO layers were treated with swift heavy ion irradiation (100 MeV Ag ions, 1013 ions/cm2). The structural properties of the pristine as well as the ion irradiated samples were investigated using synchrotron grazing incidence x-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) techniques. XRD shows peaks corresponding to Pd (FCC, space group-Fd-3m), GO and synthetic graphite. The relative graphite peak intensities increased after ion irradiation, indicating reduction of GO. The sensor responses of nanocomposite layers towards exposure of 35 ppm H 2 at 100 °C, were measured for several cycles. Ion-irradiated Pd-GO samples show enhancement in the sensing response of H 2 gas by about 24% and with lower recovery times (25%), as compared to pristine Pd-GO nanocomposite samples. The change in type of conductivity from p-type gas sensing layer in pristine nanocomposite to n-type conductivity, along with an increase in conductivity (about 500 times) in ion irradiated samples were observed. The change in type of conductivity on ion-irradiation is attributed to the reduction of GO layer and the changes in conductivity on hydrogen exposure is explained due to hydrogen spill-over effect in the two-component system. The improvement in sensitivity upon ion-irradiation was due to the increase in concentration of structural defects due to electronic energy loss, as studied by SRIM simulation. This study points towards using ion induced electronic energy loss as a new tool for varying the gas sensing properties of GO based sensors. • Pristine and SHI irradiated Pd-GO nanocomposite layers were used as hydrogen sensors. • Irradiated sensors showed about 25% more sensor response (SR) and 25% faster recovery time. • Pristine/SHI irradiated sensors showed p-type/n-type conductivity. • Change in conductivity of the sensors was explained by hydrogen spillover effect in two component system. [ABSTRACT FROM AUTHOR]

We report the improvement of electric and magnetic properties of the chemical routed samples of Co 1.25 Fe 1.75 O 4 ferrite. Synchrotron X-ray diffraction pattern confirmed the cubic spinel structure in all samples. Raman spectroscopy provided the information of mixed-type cubic spinel structure, where Co 2+ and Fe 3+ ions order both in octahedral and tetrahedral sites. The thermal heat treatment has brought a systematic change in electric polarization and magnetic parameters. At a critical annealing temperature ( T AN ) of 800 °C, the sample has shown the highest magnetic coercivity ~596 Oe and relatively large squareness ~0.5. The electrical conductivity, dielectric loss and dielectric constant have decreased with increase of T AN . The dielectric constant becomes stable for T AN above 800 °C. The samples annealed in the temperature range 900–1000 °C have shown a good signature of ferroelectric polarization, although it is under saturation value and leakage of polarization due to conductive effect is observed. This work shows the scope of the improvement of electric polarization due to capacitive effect on increasing the annealing temperature of as-prepared Co ferrite sample. [ABSTRACT FROM AUTHOR]

In this paper, we describe the design and development of helical cut smooth wall mode launcher for high frequency and high power Gyrotron. A Vlasov-type helical cut mode launcher for converting TE 22,6 mode to a Gaussian mode has been designed for 120 GHz, 1 MW Gyrotron. The initial design of mode launcher has been optimized using LOT/SURF-3D software. The mode launcher diameter and length are optimized considering the minimum return loss and the minimum insertion loss by using CST microwave studio. The return loss (S 11 ) and insertion loss (S 21 ) performance of helical cut smooth wall mode launcher have been obtained using CST-Microwave Studio. The fabrication of Vlasov-type helical cut mode launcher for 120 GHz Gyrotron has also been carried out. [ABSTRACT FROM AUTHOR]

The paper describes the pilot project on the establishment of National Ambient Noise Monitoring Network ( NANMN ) across seven major cities in India for continuous noise monitoring throughout the year. The annual average L day (06–22 h) and L night (22–06 h) values observed since past three years are described. The long-term noise monitoring shows that ambient noise levels have marginally increased since past three years in the 35 locations under study in which 14 locations are in commercial zone, 5 in Industrial, 7 in residential and 9 in silence zones. The study is very helpful in ascertaining the magnitude of annual average ambient noise levels, planning for noise abatement action plans and formulation of revised ambient noise standards in Indian scenario. [ABSTRACT FROM AUTHOR]

Very intense and highly dynamic eastward and westward currents flowing in the auroral ionosphere are traditionally monitored by the auroral electrojet indices – AU and AL , respectively. In this study we show that on occasions of intense magnetic activity, entire auroral oval could be dominated by the westward flowing currents, which lead to depression not only in AL index but also in supposedly positive AU index. During negative AU intervals, there could be up to ∼ 20 % underestimation of the total maximum intensity of the auroral electrojet represented by AE index ( defined as AU - AL ). A detailed investigation of a well-studied extremely intense event of 24 August 2005 has been carried out. Global prevalence of the westward auroral electrojet was clearly observed at the auroral latitudes during the unusually intense substorm ( AL ∼ - 4000 nT) on the day. Moreover, along the noon meridian westward electrojet appeared in the auroral region whereas eastward electrojet shifted towards lower latitudes. This paper emphasizes that intense substorms are represented better by AL index than AE index. [ABSTRACT FROM AUTHOR]

Abstract: X-ray absorption near edge structure (XANES) spectroscopy, X-ray photoelectron spectroscopy (XPS), and Synchrotron X-ray diffraction (SXRD) techniques are used to study as synthesized and isochronally annealed samples of cobalt oxide nanoparticles (NPs) grown using the wet chemical route. Quantitative phase composition determined using Linear Combination Fitting (LCF) on XANES data is found to be in reasonably good agreement with that obtained from Rietveld refinement on SXRD data. XPS data qualitatively indicate that Co3O4 concentration increases with increase in the annealing temperature, in confirmation with SXRD and XANES data. Larger shifts in the satellite peaks from the main peaks compared to these in bulk suggest larger crystal field splitting in nanoparticles as compared to the bulk. [Copyright &y& Elsevier]

Abstract: Onset of a geomagnetic substorm often intensifies the westward auroral electrojet, as well as produces asymmetric magnetic field at low-/mid-latitudes. Auroral electrojet and low latitude asymmetric indices are known to correlate well during substorms. These indices have been widely used to monitor the duration and strength of substorm activities. However, several processes, other than substorms, introduce local time asymmetry in magnetic field at low latitudes, which can substantially influence the ASY indices. Large number of substorms are observed in association with changes in the interplanetary magnetic field (IMF). It is known that sharp IMF Bz orientation changes result in penetration of interplanetary electric field (IEF) to lower latitudes, which affects the geomagnetic fields to different degree in different local times. In the present study, we demonstrate that sharp IMF Bz fluctuations during the expansion phases of substorms introduce additional asymmetry at low latitudes. The effect is clearly seen in ASYH, whereas ASYD remains almost unaltered. [Copyright &y& Elsevier]

Abstract: Magnetic data from a newly commissioned Indian Antarctic station Bharati (corrected geomagnetic (CGM) coordinates 74.7°S, 97.2°E) and closely-spaced IMAGE chain observatories (∼100° magnetic meridian in Northern hemisphere) has been analyzed to study the climatology of substorms which were localized poleward of the standard auroral oval. We considered four austral summers (year 2007–2010) when data from Bharati was available. Several very high latitude substorms were observed in this duration when the solar activity remained unexpectedly low for a long time. Various features of very high latitude substorms, e.g., local time dependence, interplanetary state, hemispherical asymmetry and their nightside low latitude signatures are examined. Events studied here, suggested the following properties of substorms occurring at very high latitudes: (1) maximum occurrence was observed near magnetic midnight (21:00–02:00 MLT). (2) In contradiction to earlier reports, many substorms were observed even during negative IMF Bz condition. In addition, majority of substorms occurred during low or moderate solar wind streams. (3) Magnetic signatures were often pronounced in the winter hemisphere. (4) Even if widely used standard AE indices fail to monitor very high latitude substorms, their low latitude signatures are often evident. [Copyright &y& Elsevier]

Abstract: Power system state estimation with exclusive utilization of synchronous phasor measurements demands that the system should be completely observable through PMUs only. To have minimum number of PMUs, the PMU placement issue in any network is an optimization problem. A three stage optimal PMU placement method is presented in this paper using network connectivity information. The method initially considers PMU in all buses of the network. Stage I and Stage II of the algorithm iteratively determine (i) less important bus locations from where PMUs are eliminated and (ii) strategically important bus locations where PMUs are retained. Stage III of the algorithm further minimizes the number of PMU using pruning operation. The set of PMUs obtained after Stage III is an optimal set of PMU locations for network observability. Proposed method is further extended for assuring complete observability under single PMU outage cases. Simulation results for IEEE 14-bus, 24-bus, 30-bus, 57-bus, 118-bus and New England 39-bus test systems are presented and compared with the existing techniques. Results show that the proposed method is simple to implement and accurate compared to other existing methods. [Copyright &y& Elsevier]

• The relative dominance between IMF and SI in triggering a substorm. • Ground and satellite based analysis of impulse induced substorms. • Solar wind particle injection via viscous interaction during substorms. • Importance of SML-LT index in identifying the triggering agent of substorm onset. • Substorm onset far away from usual midnight. During a typical Akasofu-type of substorm, the southward component of IMF Bz is necessary prior to the onset. However, a sudden compression of solar wind, if intense enough, can also sometimes trigger a substorm, and is independent of the IMF orientation. The Akasofu-type substorm and the Impulse-induced substorm may differ in their occurrence mechanism and ground-based observations. This is shown using the initial four substorm events discussed in this paper having distinctly different IMF and sudden impulse conditions. A question then arises is how will these signatures vary when both sudden impulse and a southward component of IMF Bz are present prior to the onset. To account for the same, we analyze two substorm events of 05th April 2010 and 22nd June 2015. The substorm onsets on these days not just coincided with the sudden impulse but also a southward component of IMF Bz was present prior to the onsets. The present study accounts for the similarities and differences among isolated IMF induced substorms, isolated impulse-induced substorms and when both sudden impulse and a southward component of IMF Bz are present. We examined the relative dominance between the two factors in triggering a substorm using ground-based and satellite-based observations. If IMF Bz is near zero, a strong pressure pulse and/or large IMF By can lead to particle precipitation away from the usual midnight. To further ensure whether a pressure pulse or IMF By predominantly influences the substorm onset location, a statistical analysis of isolated substorms will be needed. [ABSTRACT FROM AUTHOR]

Abstract: Low latitude asymmetric (ASY) indices in addition to auroral electrojet (AE) indices have been widely used to monitor magnetic substorm phenomenon. However, low latitude ASY indices are strongly affected by various current systems in the magnetosphere and the ionosphere which may not have any direct relation with substorm activity. In this paper we investigate the effect of solar flares on non-substorm and substorm times ASY indices using solar flare and indices data during the solar cycles 22 and 23 (year 1986–2008). We observe that during quiet magnetospheric conditions, long-lasting intense solar flares generate asymmetry similar to substorm events in ASY indices. In addition, substorm time ASY indices are also substantially affected by intense solar flares. [Copyright &y& Elsevier]

Abstract: We show examples of long period Pc5 magnetic field pulsations near field-aligned current (FAC) regions in the high-latitude magnetosphere, observed by INTERBALL-Au, and coordinated with POLAR, GOES-9 and ground-based observations during 11 January and 11 April 1997. Identification of corresponding magnetosphere regions and subregions is provided by electrons and protons in the energy-range of 0.01–100keV measured onboard the spacecraft. The ULF Pc5 wave occurrence is observed in both upward and downward FACs. A fairly good correlation is demonstrated between these ULF Pc5 waves and the consecutive injection of magnetosheath low energy protons. The constancy of the observed frequency peak at 1.8mHz during quite unsteady solar wind pressure conditions could be reconciled with the surface wave mode model. The 3.1mHz peak location area probably resembles field-line fluctuations with an interesting appearance of poloidal mode oscillation. It is suggested that the 1.3mHz wave and its harmonic 2.6mHz represent global compressional oscillations. [Copyright &y& Elsevier]

Abstract: Resonant soft X-ray reflectivity measurements at and near the L3 absorption edge of sulphur have been performed on mechanically polished zinc sulphide using Indus-1 synchrotron source. A sulphur rich surface (∼15nm thick) consisting of two layers with gradient electron density distribution was uniquely determined. As compared to bulk ZnS, the top layer has ∼30–50% less electron density whereas, the intermediate layer has ∼10–18% less electron density. Conventional hard X-ray reflectivity measurement at Cu Kα wavelength also indicates low electron density (sulphur rich) surface of ZnS but the technique was found insensitive for unique determination of electron density distribution. Optical constants of ZnS in the soft X-ray region (100–250eV) have been reported for the first time and were in good agreement with the theoretically reported values. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an efficient and realistic contingency analysis method. The contingencies are ranked based on their risk index value which incorporates both the probability and the severity of the contingency. Severity for each contingency is computed based on load loss, equipment overloads, voltage magnitude violation at nodes and system frequency deviation from the nominal value. The proposed method considers line/transformer outages as well as generator outage contingencies. A modified Fast Decoupled Power Flow method which considers frequency and voltage dependent characteristic of loads, generator regulation characteristics and sensitivity based transformer tap adjustments is used to evaluate the contingencies. The power flow method is suitable for any AC/DC power system and can carry out contingency analysis even if the system gets islanded. [Copyright &y& Elsevier]

A prototype chip fabricated in 130 nm CMOS technology, designed to extract maximum power from a thermoelectric generator (TEG) is presented. In the measurements, the TEG is modelled by a voltage source (VTEG) with a series resistance of 5 Ω. The prototype is fully electric, starts from VTEG = 50 mV and it can extract 60% (at 50 mV) to 65% (at 200 mV) of the available power. Also by using present circuit schematic, an improved transient response of 3 ms (at 50 mV) and startup voltage of 50 mV is achieved. [ABSTRACT FROM AUTHOR]

Abstract: Prefabricated Vertical Drains (PVDs) are being used to accelerate the consolidation of subsoil for construction of high embankment on soft ground. The construction is carried out in stages and height of the first stage construction depends on in-situ undrained shear strength. Each subsequent stage construction is carried out after completion of either 90% primary consolidation or percent consolidation at inflection point. The height of subsequent stages depends upon the gain in undrained strength of subsoil. In this paper, the authors have advocated an approach to shorten the construction period for high embankments. In this approach, the first stage construction would be carried out based on the in-situ undrained shear strength of subsoil. Instead of waiting for 90% primary consolidation or percent consolidation at inflection point, the embankment is raised in layers of 0.2m thickness. Based on the time required to gain strength with the construction of the 0.2m layer, the waiting period is determined for each subsequent layers. The waiting period depends on soil parameters such as subsoil thickness, C r/C v ratio and different PVD factors viz. smear, drain spacing and well resistance, pattern of laying of PVD, etc. Using this approach, there would be increase in the consolidation rate and overall reduction in the construction period. A typical practical example has been solved to demonstrate the usefulness of this approach over the two conventional methods. For a 4.5m high embankment, it is observed that waiting period is reduced by 77% and 43% as compared to the 90% primary consolidation method and inflection point method respectively. [Copyright &y& Elsevier]

Abstract: We report Raman spectroscopy and electron microscopy studies on multi-walled carbon nanotubes annealed in hydrogen atmosphere at low temperatures (<1300°C). The pristine samples have different I D/I G ratios (ratio of the area of D peak to the area of G peak in the Raman spectra) between 0.19 and 2.6. I D/I G ratio represents defect density in graphitic structures. We find that as the annealing temperature is increased, I D/I G ratio first increases and then decreases. The annealing temperature at which the I D/I G ratio is maximum, decreases with increasing the pristine I D/I G value. We explain this by invoking a mathematical expression for I D/I G ratio, consisting of an exponential and a stretched exponential term for production and annealing of defects, respectively. The obtained activation energies and the pre-exponential factors of the two contributions are found to vary systematically with pristine I D/I G ratio. The contributions of various carbon phases to I D/I G ratio on annealing have been discussed. [Copyright &y& Elsevier]

Analysis of complex systems has migrated from theoretical analysis of model physical systems into the domain of real-world applications with far-reaching implications. This shift has been facilitated by the availability of measurement data, the capability to store and manage large-scale datasets, and significant increase in computational power. These developments have been matched by a concerted effort in the development of new methods of complex systems analysis. Each class of analytical methods are applicable only for certain system types and specific problems, such as estimating causality between coupled complex systems, are still unresolved even for simples cases involving only two connected systems. This study summarizes results for estimating causality using a novel mathematical computational model, System Structure, across several different types of coupled systems. System structure models a system as a dynamic network of connected components and provides a distribution-free and systematic quantification of inter-component dynamics as a basis for making several system-wide inferences including the inference of strength and direction of causal relations. System structure is a non-parametric scalable method that requires few non-restrictive a-priori assumptions, making it generally applicable across a diverse set of problems. The comparative study reported on here demonstrates the ability of system structure to correctly infer different types of causality across diverse system types. • A novel computation method for complex systems analysis. • Estimating coupling in Systems and Systems. • Estimating causality in Systems of Systems. [ABSTRACT FROM AUTHOR]

Abstract: Prefabricated vertical drains (PVDs) are being used to accelerate the consolidation of subsoil for construction of high embankments on soft ground. The construction is carried out in stages and the height of each stage construction depends on gain in strength of soft subsoil and target factor of safety. The inflection point method for estimating the degree of consolidation for vertical drainage has previously been published. The degree of consolidation was estimated to be 70% at the inflection point. After 70% consolidation, the rate of consolidation reduces to a minimum value and it is economical and technically feasible to allow the second-stage loading. Additional load at this stage would ensure increase in shear strength of the subsoil. In this paper, the authors have extended the procedure of inflection point method for vertical drainage to a three-dimensional drainage when PVDs are adopted for subsoil improvement. Theoretical graphs have been developed which can estimate the percent consolidation at inflection point (% U i) for different subsoil thickness, drain spacing ratios and C r/C v ratios. Different factors viz. smear, drain spacing, depth of clay thickness and well resistance were also considered in the analysis. The degree of consolidation at inflection point is observed in the range of 61–78%. The inflection point method has been applied to a settlement data from a case history of two sites and the estimated percent consolidation at inflection point has been compared with the values predicted from developed theoretical graphs. The total primary settlement estimated from inflection point has been compared with that of Asaoka method, which is widely used in the field. It is concluded that inflection point method has the potential for field application and provides an alternate method for estimating of total settlement in field applications using PVDs and surcharge, and to determine the appropriate required waiting period for stage loading. [Copyright &y& Elsevier]

Abstract: Objective: To compare the effects of the two modes of ventilation, synchronous intermittent positive pressure ventilation (SIPPV) and SIPPV with Volume Guarantee (VG), on arterial carbon dioxide tension (PaCO2) immediately after neonatal unit admission. Study design: Randomised study of ventilation mode for premature inborn infants admitted to two tertiary neonatal units. After admission, infants were randomised to receive either SIPPV or VG using a Dräger Babylog 8000 plus ventilator. In the SIPPV group, peak airway pressure was set clinically. In the VG group, desired tidal volume was set at 4 ml/kg, with the ventilator adjusting peak inspiratory pressure to deliver this volume. The study was completed once the first arterial PaCO2 was available, with the desirable range defined as 5–7 kPa. Results: PaCO2 was significantly higher in the VG group (VG: 5.7 kPa, SIPPV: 4.9 kPa; p =0.03). The VG group had fewer out-of-range PaCO2 values (VG: 42%, SIPPV: 57%) and fewer instances of hypocarbia <5 kPa (VG: 32%, SIPPV: 57%) but neither difference achieved statistical significance. Regression analysis showed PaCO2 was negatively correlated with gestation (r =−0.41, p =0.01) and also with the mode of ventilation (r =0.32, p <0.05). In the VG group, all infants 23–25 weeks'' gestation had out-of-range PaCO2 values. VG significantly reduced the incidence of out-of-range PaCO2 and hypocarbia in infants over 25 weeks'' gestation (VG: 27%, SIPPV: 61%; p <0.05). Conclusion: Using this strategy, VG appears feasible in the initial stabilisation of infants over 25 weeks'' gestation, with a halving of the incidence of hypocarbia. In the small number of babies studied below this gestation, VG was not found to be effective. [Copyright &y& Elsevier]

Abstract: The mineralogy and geochemistry of soils developed over the unmined Coles Hill uranium deposit (Virginia) were studied to determine how phosphorous influences the speciation of uranium in oxidizing soil/saprolite systems typical of the eastern US. Results from this study have implications for both uranium remediation (e.g. in situ stabilization) and uranium resource exploration (e.g. near-surface geochemical sampling). The primary uranium ore (coffinite and uraninite hosted in quartzo-feldspathic gneiss) weathers to saprolites containing the same uranium concentration as the underlying ore (approximately 1000 mg U/kg saprolites). In these water saturated (below water table) saprolites the uranium is retained as uranyl phosphates of the meta-autunite group (mainly meta-uranocircite). Above the water table the soils overlying the deposit contain approximately 200 mg uranium per kg soil (20 times higher than uranium concentrations in similar soils formed from unmineralized rocks adjacent to the deposit). In these unsaturated zone soils uranium is retained by two processes: (1) incorporation into barium–strontium–calcium aluminum phosphate minerals of the crandallite group (mainly gorceixite), and (2) sorption of uranium with phosphorous onto iron oxides that coat the surfaces of other soil minerals. Thermodynamic calculations suggest that the meta-autunite group minerals present in the saprolites below the water table are not stable in the unsaturated zone soils overlying the deposit due to the drop in soil pH from ∼6.0 down to ∼4.5. Mineralogical observations suggest that, once exposed to the unsaturated environment, the meta-autunite group minerals react to form U(VI)-bearing aluminum phosphates and U(VI) surface complexes or nano-precipitates associated with ferric oxides. These results therefore indicate that models predicting U(VI) speciation in phosphate amended soils must simultaneously account for variations in pH, ion activities (aluminum appears to be particularly important) and surface complexation with iron oxide mineral surfaces. [Copyright &y& Elsevier]

Abstract: In developing country such as India, demand for power is increasing day by day; especially peak load demand management is becoming crucial. This paper highlights the gap between peak load power demand and availability of power at the regional level, furthermore proposes the suitability of power generation from renewable sources to fill the gap. The problem is formulated for the optimum allocation of the various renewable energy options to meet the peak load demand at the regional level of India, based upon the application of a linear programming algorithm, considering various constraints. Due to the geological profile, potential of various renewable energy sources such as, small hydel power, solar photovoltaic, wind power, co-generation and biomass energy is varying from region to region. A computational result indicates that the power generated by renewable resources is quite suitable to meet the peak load demand and in fact some of regions have the potential, which can be transferred to the other regions utilizing the existing transmission line network. [Copyright &y& Elsevier]

Abstract: An effort was made to analyze the effect of in vitro stimulation on macrophages using killed Shigella dysenteriae type-1 (KSD1) coupled with anti-Interferon Gamma (anti-IFN-γ) antibody. The stimulated macrophages were co-cultured with primed or non-primed T-cells from Shigella infected patients. T-cell cultures were also established by co-culturing KSD1 coupled with or without PHA stimulated macrophages. Emulsified KSD1 coupled with anti-IFN-γ antibody was found to act as a potent immunogen, inducing the release of Th1 cytokine from primed T-cells cultured in acute stage of the disease. It was observed that the levels of IFN-γ and IL-2 production rather than IL-4 and IL-6 were increased as the disease became more severe. On comparison, the subsequent values of IL-6, IFN-γ, IL-4 and IL-2 were found to be less significant in healthy primed T-cell cultures. This was also associated with a substantial production of superoxide ions (O2 −), which probably inhibits the colonization of intracellular Shigella due to the presence of anti-IFN-γ antibodies. On the other hand KSD1 with or without PHA failed to induce such responses. The above findings reflect that in the presence of anti-IFN-γ antibody, KSD1 acts as a potential immunogen for eliciting cellular immunity against shigellosis. [Copyright &y& Elsevier]

Abstract: This paper describes a method of congestion management by generation rescheduling and load shedding. The sensitivities of the overloaded lines to bus injections and the costs of generation and load shedding are considered for ranking the generation and load buses. The new generation and load shedding schedule for these buses are then computed based on a simple method considering cost and sensitivity to line currents. The algorithm will help the system operator to generate the contingency plan quickly for secure operation of the system. Test results for three systems are presented. The results show that cost effective generation rescheduling and load shedding plans can be obtained to alleviate overloading of the transmission lines in a computationally efficient manner. [Copyright &y& Elsevier]

Medium-pore SAPO-11 and SAPO-31 molecular sieves were synthesized from aqueous and non-aqueous (ethylene glycol) media. All the samples were characterized by XRD, SEM, N2 adsorption (BET analysis), TGA-DTA, pyridine-TPD, 27Al MAS-NMR, and 29Si MAS-NMR. The samples synthesized from non-aqueous medium possess higher acidity due to higher substitution of Si4+ at P5+ sites and less silica island formation, as evidenced from 29Si MAS-NMR spectra. It is possible to incorporate more silicon in the samples by synthesis in ethylene glycol medium. The SAPOs synthesized from non-aqueous medium show higher activity for the isomerization of m-xylene. [Copyright &y& Elsevier]

Supported nano-gold catalysts have attracted rapidly growing interest due to their potential applicability to various reactions of industrial and environmental significance. In this article, we focus on the advances related to the direct vapor-phase oxidation of propene to propene oxide in the presence of molecular oxygen and hydrogen over gold catalysts supported on Ti-incorporated silica materials prepared by different methods. The importance of catalyst preparation and pretreatment method, nature of support material, Au particle size and loading amount is emphasized. Possibilities to enhance the catalyst performance by using promoters and by silylation are also discussed. [ABSTRACT FROM AUTHOR]

Geochemical and mineralogical studies of the 15- to 20-m-thick soil and saprolite profile developed over the Coles Hill uranium deposit demonstrate that uranium transport may be inhibited or naturally attenuated by the precipitation of U(VI) phosphate minerals in oxidizing and saturated soil environments. This study examines geochemical conditions in which these secondary uranium phosphates are formed and remain stable for hundreds of thousands of years. We also describe geochemical conditions that may lead to their dissolution.The lower part of the weathering profile, which consists of groundwater saturated saprolite, contains up to 1300 mg/kg uranium (within the solid). This concentration is approximately 1.5 times greater than the average ore grade of the deposit, indicating that the saturated saprolites are enriched relative to the underlying primary ore. Uranium within this zone is dominantly associated with U(VI) phosphates of the meta-autunite mineral group. Groundwaters from this zone contain less than 14 μg/l uranium suggesting that the U(VI) phosphate minerals present within the Coles Hill saprolites are capable of buffering dissolved uranium concentrations to values significantly lower (by a factor of 2 or more) than the US-EPA maximum contaminant level of 30 μg/l.Above the water table, U(VI) phosphates of the type found in the saturated saprolite zone are not present, and the soil uranium concentration drops to an average value of 250 mg/kg. Thus, the zone of water table fluctuation represents a major transition zone in uranium mineralogy. Mineralogical characterization of the upper part of the profile suggests that geochemical conditions in the unsaturated zone are not conducive to uranium stabilization by meta-autunite group minerals. Uranium within the vadose zone, however, is associated with phosphate (e.g. Al phosphate minerals and sorption with phosphate to ferric oxyhydroxides).As a whole, the Coles Hill soil profile is interpreted to have reached a steady state with respect to uranium transport and immobilization. Results of this study suggest that uranium is leached from the unsaturated part of the profile (meta-autunite unstable) and reprecipitated below the water table where the measured activity ratio of dissolved phosphate to carbonate is higher. Based on estimates of weathering rates for this region, the processes responsible for the dispersal of uranium within the Coles Hill system are estimated to have been active on a time scale of hundreds of thousands of years. This system thus represents an excellent natural laboratory for understanding the long-term mineralogical and geochemical processes involved in the coupling of uranium and phosphorus in natural, fluid-rich systems. [Copyright &y& Elsevier]

The unmined Coles Hill U deposit of south central Virginia represents a natural setting where U is stabilized by phosphate mineral precipitation in an oxidizing bedrock aquifer. Drill cores from the shallow portion of the deposit preserve a sharp Fe redox front defined by Fe(III) oxide staining. This front is located near a discontinuity in U mineralogy with U(IV) assemblages (e.g. coffinite, uraninite) on the reducing side, and U(VI) assemblages on the oxidizing side. The discontinuity in U mineralogy does not, however, represent a major discontinuity in whole rock U concentrations, with sample groups from both oxidized and reduced sides of the front generally ranging from 500 to 1000 ppm. This observation suggests that the volume of shallow bedrock associated with the deposit has not lost significant amounts of U during the oxidation and incipient chemical weathering. The precipitation of Ba uranyl phosphate (Ba meta-autunite) is responsible for U retention within this zone. Ground waters sampled from the weathered bedrock aquifer associated with the deposit contain less than 15 μg l−1 dissolved U. This suggests that the low solubility of the Ba meta-autunite limits U concentrations to values lower than the US-EPA maximum contaminant level of 30 μg l−1. Ground water speciation and mineral saturation calculations show that, in addition to Eh and pH, the most important factor controlling this U fixation process is the activity ratio of dissolved phosphate to dissolved carbonate. Experimental results suggest that, at the Coles Hill site, the oxidation of U(IV) to U(VI) and subsequent precipitation of uranyl phosphate occurs rapidly (time scale of weeks) relative to ground water transport (e.g. 20 m/a). Furthermore, based on the rate of downward migration of the redox front, it is estimated that the oldest U(VI) phosphate assemblages associated with the Coles Hill U deposit have been stable for up to 150 ka. These observations have important implications for the design and long term performance assessment of phosphate-based stabilization and reactive barrier techniques. [Copyright &y& Elsevier]

This paper describes a restoration guidance simulator, which allows power system operator/planner to simulate and plan restoration events in an interactive mode. The simulator provides a list of restoration events according to the priority based on some restoration rules and list of priority loads. It also provides in an interactive mode the list of events, which becomes possible as the system grows during restoration. Further, the selected event is validated through a load flow and other analytical tools to show the consequences of implementing the planned event. [Copyright &y& Elsevier]

Ti-containing MCM-41 supports were prepared by: (a) hydrothermal crystallization; (b) post-synthesis grafting; and (c) two-step Ti incorporation—hydrothermal incorporation followed by post-synthesis grafting. XRD revealed little change in crystallinity and long range order of MCM-41 phase after Ti incorporation by different methods. UV-Vis spectra show the presence of tetrahedral Ti sites at lower Ti contents (upto 4.5 mol%), but aggregated titania formation could be observed at higher Ti loadings (>4.5 mol%). The samples exhibit surface areas and pore volumes in the mesoporous range. Vapor phase epoxidation of propene using H2 and O2 was carried out over these supports after Au deposition by deposition-precipitation (DP) method. The Ti-MCM-41 supports prepared by two-step Ti incorporation (with up to 4.5 mol% input Ti), which probably have more number of isolated Ti sites, showed higher catalytic activity than Ti-MCM-41 prepared by one-step Ti incorporation method, at comparable propylene oxide selectivities and hydrogen efficiencies. The former catalyst also deactivates more slowly than the latter ones, probably due to a decrease in the number of silanol sites (those responsible for deactivation) due to grafted Ti. [Copyright &y& Elsevier]

Ti-MCM-41 samples were used for propene epoxidation using H2 and O2 after Au deposition by deposition--precipitation. Au nanoparticles supported on Ti-MCM-41 with Ti incorporated hydrothermally followed by post-synthesis grafting gave higher propene oxide yields than Ti-MCM-41 with Ti incorporated hydrothermally or by grafting. Au L3-edge EXAFS spectra show the presence of metallic Au for the low Au content (0.21 wt%) catalyst which is more selective to epoxidation, while at high Au loadings (0.42 wt%) oxidic Au species are observed and the catalyst shows lower epoxide selectivity. [ABSTRACT FROM AUTHOR]

Metal phthalocyanine complexes (MPc; M=V, Co and Cu) were encapsulated in zeolite-Y by “in situ ligand synthesis” method and were characterized by chemical and thermal analyses, FT-IR, diffuse reflectance UV–VIS and EPR spectroscopic techniques. The Pc moiety undergoes distortion from square planarity on encapsulation. The studies have provided evidence for the encapsulation of MPc inside the supercages of zeolite-Y. The encapsulated complexes exhibited enhanced phenol hydroxylation activity with H2O2 compared to the “neat” complexes in homogeneous medium. A comparative study has revealed that the activity and product selectivity of the encapsulated complexes can be correlated with the redox potential of the M(n+1)/Mn+ couple of the central metal atom of the encapsulated phthalocyanine. [Copyright &y& Elsevier]

Presents a method for the reduction of excessive standing phase angle (SPA) difference between two buses via generator rescheduling, subject to the generation limits. Role of system restoration; Shocks that closing of a circuit breaker on a large SPA difference may cause to the power system; Excessive SPA difference across buses that are to be connected by a transmission line.

Presents an algorithm for dynamic state estimation of power systems. Attempt to model dynamics of power system into the state estimation process; Short-Term Load Forecasting (STLF) as one of the application areas of the Artificial Neural Network (ANN); Dependence of bus voltage variations on load changes.

The result of an equivalent circuit analysis developed here suggests the employment of an inhomogeneous dielectric support as an effective means of dispersion-shaping a helical slow-wave structure used in wide-band travelling wave tubes. [ABSTRACT FROM AUTHOR]

Designs a hyperbolically tapered microstrip transmission line for matching a complex load to a standard coaxial cable, based on the solution of the Riccati equation. Use of an iterative procedure to yield the phase constant leading to an accurate design; Miniturization of solid state circuits; Numerical example for the case of an arbitrary complex load.

Aluminium hydroxide (Al(OH) 3) was prepared by chemical reaction of the Al(NO 3) 3 in alkaline medium. The as-prepared powder was heated in the temperature range 250 °C to 1250 °C for studying the structural phase transformation at different stages of the heat treatment. The synchrotron x-ray diffraction patterns confirmed a structural transformation of Al(OH) 3 through different (Boehmite, γ, θ, δ, and α) polymorphic phases of Al 2 O 3 on increasing the heat treatment temperature. The samples in Boehmite (γ-AlOOH) and α- Al 2 O 3 phases showed Raman active modes, whereas the intermediate (meta-stable) multi-phased structure showed weak Raman active peaks. The analysis of UV–visible spectra of the samples indicated two optical band gap energy values in the high energy range 4.50–4.73 eV and low energy range 3.06–3.84 eV. The voltage dependence of current, capacitance and electrical polarization were recorded to study electrical properties in heat treated samples. The capacitance value, derived from the polarization, showed a usual increasing trend on decreasing the measurement frequency (inverse of the time) of driving electric voltage. The measured electrical polarization in the samples was found to be highly correlated to their electrical conductivity and the results are helpful to understand the role of electrical conductivity on exhibiting the apparently ferroelectric properties in high conductive and low polarizable dielectric oxides. [ABSTRACT FROM AUTHOR]

BiFe 1-x Co x O 3 (x = 0.00, 0.01, 0.03, 0.05 and 0.07) nanoparticles (NPs), were prepared by ethylene-glycol-based sol-gel technique. Phase purity of the NPs was confirmed by x - ray diffraction (XRD) technique. The average size of pristine BiFeO 3 (BFO) NPs was found to be 46 nm, which initially increased to 50 nm for 1% Co doping and then decreases to 48, 45 and 43 nm for 3%, 5% and 7% Co-doped BFO NPs, respectively. X-ray photoelectron spectroscopy (XPS) and Mössbauer spectroscopy confirmed that the oxidation state of Fe and Co is +3. In the low frequency region, the dielectric constant (ε ') shows a maximum decrease by 96% (137 → 5.1) on 5% Co-doping concomitant with 62% decrease in dielectric loss (0.32 → 0.12) which indicates substantial reduction in leakage current density. Further, the pristine BFO shows a well-defined dielectric loss peak at 40 Hz (tan δ = 0.4). In contrast, twin dielectric loss peaks are uniquely observed for all the Co doped BFO NPs. 1% doped NPs show first and second peaks at 7 Hz and 20,400 Hz, respectively, which shifts to higher frequencies of 245 Hz and 154,000 Hz, on 5% doping. The magnetic measurements (M − H) revealed the ferromagnetic behaviour of the NPs. On Co doping, saturation magnetization (M s) increased with decrease in coercive field (H c). A maximum enhancement of 226% (0.93 → 3.05 emu/g) in M s values concomitant with decline of 61% in H c values (80 → 15 Oe) was observed for 7% doping. The reduction in leakage current and enhancement of magnetic properties makes the NPs better-suited for device applications. Image 1 • Pristine and Co-doped BiFeO 3 NCs have been prepared using ethylene glycol-based sol-gel technique. • In the low frequency region, ε' decreases by 96% on 5% Co-doping alongwith 62% decrease in tan δ. • A single dielectric loss peak is observed for pristine BFO NCs whereas twin peaks are observed for all the Co doped NCs. • A maximum enhancement of 226% in M s values concomitant with decline of 61% in H c values was observed for 7% doping. • A gradual blue shift ranging upto 82 nm (592 nm to 510 nm) has been observed in UV-Visible absorption spectra. [ABSTRACT FROM AUTHOR]

Our present work is aimed at increasing the degree of graphitization of carbon black during the synthesis stage itself. For this purpose, we used lamp black route to synthesize carbon black via catalytic graphitization using ferrocene as an organometallic additive into the precursor olive oil. Degree of graphitization was estimated using Raman spectroscopy and microstructure was determined using transmission electron microscopy (TEM). We found that the degree of graphitization as quantified by the Raman spectroscopy could be doubled by changing the concentration of ferrocene into the precursor oil. The TEM images show the presence of multi-layer graphenes, a few tens of nanometers large, which were completely absent when no additive was used. It is proposed that iron plays the role of graphitization enhancer as Raman, TEM and X-Ray diffraction (XRD) measurements show the presence of iron compounds in the product. Oxidation of iron catalyst mainly limits further growth of graphitic clusters. Unlabelled Image • Ferrocene/olive oil based synthesis of carbon black (CB) via lampblack route. • Graphitization of CB increased through ferrocene derived iron as catalyst. • I G /I D ratio in Raman spectra of CB increases from 0.31 to 0.49. • XRD shows Graphite/amorphous carbon ratio increases by 2 upon catalyst use. • Multilayered graphene as well as graphitic bamboo-like structures were observed. [ABSTRACT FROM AUTHOR]

Highlights • HRXRD characterization of MBE grown AlGaN/AlGaN Multi quantum wells (MQW) is carried out where useful information related to the composition and thickness of MQW is obtained. • Further, an anomalous peak is observed in the experiments which is not predicted by the numerical simulations based on the dynamical theory of X-ray diffraction. • Origin of the anomalous peak is investigated which is found to be related with some unknown scattering occurring in the X-ray optics of hybrid monochromator. • A simple method to eliminate the anomalous peak is also given which ensures the usefulness of HRXRD for studying AlGaN/AlGaN MQW structures. • A word of caution is also proposed that the origin of anomalous peak should be investigated first before assigning the same to a fundamental physical phenomenon. Abstract Features related to AlN buffer layer, thick AlGaN bottom layer, and AlGaN quantum well structure are identified by performing High resolution X-ray diffraction (HRXRD) measurements on Al 0.4 Ga 0.6 N/Al 0.6 Ga 0.4 N multi quantum well sample. HRXRD measurements reveal an anomalous peak which is not predicted by the simulations using Takagi-Taupin equations based on the dynamical theory of X-ray diffraction. However, the peak doesn't appear when the diffraction pattern is recorded using the HRXRD beam line of Indus-2 Synchrotron radiation source. Systematic investigations reveal that the anomalous peak is related to some unknown scattering originating from the X-ray optics used in the hybrid monochromator of commercial HRXRD system. It limits the usefulness of HRXRD technique for the investigation of AlGaN/AlGaN MQW samples. In view of this, a simple method for the elimination of anomalous peak from the HRXRD pattern is also demonstrated. In literature, similar anomalous peaks are often associated with the incorporation of metallic clusters, impurities, and additional crystallographic phases in epilayer. A word of caution is therefore necessary that the origin of anomalous peak in HRXRD pattern should be first confirmed before assigning the same to a particular physical phenomenon. [ABSTRACT FROM AUTHOR]

CdS-PVP nanocomposites grown with various concentrations of Cd + /S − and PVP are studied using Raman and atomic force microscopy mapping on same selected areas. The study shows that CdS nanocrystals are embedded in either a thin-film or spheres of PVP, formation of which depends on relative ratio of Cd + /S − concentration (density of nanocrystals) to PVP. Collapse of PVP from planer matrix to the sphere morphology is correlated with high density of CdS nanocrystals and the attractive interaction between CdS nanocrystals and PVP polymer leading to a co-operative growth mechanism. The understanding developed can be used to control the growth of CdS-PVP nanocomposites with desired properties for optoelectronic device applications. [ABSTRACT FROM AUTHOR]

We have prepared a composite of ferrimagnetic ferrite Co 1.75 Fe 1.25 O 4 and non-magnetic oxide BaTiO 3 . The ferrite composition Co 1.75 Fe 1.25 O 4 has been prepared by chemical co-precipitation and subsequently heated at different temperatures. The heat treated ferrite powder has been mixed with BaTiO 3 powder with mass ratio 1:1 and the mixed powder has been finally heated at 1000 °C to form composite material. Structural phase of the composite material has been confirmed by high quality Synchrotron X-ray diffraction pattern and Micro-Raman spectra. The grain surface morphology and elemental composition have been studied by Scanning electron microscope and Energy dispersive X-ray analysis. The distribution of magnetic exchange interactions and blocking behavior of the ferrimagnetic grains in composite samples has been understood by analyzing the temperature and magnetic field dependence of dc magnetization. Finally, information on modified micro-structure and ferrimagnetic parameters in composite samples has been obtained as the variation of annealing temperature of the ferrite component before making composite. [ABSTRACT FROM AUTHOR]

Describes a case of trigeminal neurinoma with an intratumoural bleeding. Sign and and symptoms; Rarity of the case.

The vector magnetic field measurements from three satellite constellation, Swarm mission (Alpha ‘Swarm-A’, Bravo ‘Swarm-B’, and Charlie ‘Swarm-C’) during the quiet days (daily ∑Kp ⩽ 10) of the years 2014–2015 are used to study the characteristic features of equatorial electrojet (EEJ). A program is developed to identify the EEJ signature in the X (northward) component of the magnetic field recorded by the satellite. An empirical model is fitted into the observed EEJ signatures separately for both the hemispheres, to obtain the parameters of electrojet current such as peak current density, total eastward current, the width of EEJ, position of the electrojet axis, etc. The magnetic field signatures of EEJ at different altitudes are then estimated. Swarm B and C are orbiting at different heights (separation ∼50 km) and during the month of April 2014, both the satellites were moving almost simultaneously over nearby longitudes. Therefore, we used those satellite passes to validate the methodology used in the present study. The magnetic field estimates at the location of Swarm-C obtained using the observations of Swarm B are compared with the actual observations of Swarm-C. A good correlation between the actual and the computed values (correlation coefficient = 0.98) authenticates the method of analysis. The altitudinal variation of the amplitude and the width of the EEJ signatures are also depicted. The ratio of the total eastward flowing forward to westward return currents is found to vary between 0.1 and 1.0. The forward and return current values in the northern hemisphere are found to be ∼0.5 to 2 times of those in the southern hemisphere, thereby indicating the hemispheric asymmetry. The latitudinal extents of the forward and return currents are found to have longitudinal dependence similar to that of the amplitude and the width of EEJ showing four peak structures. Local time dependence of EEJ parameters has also been investigated. In general, the results are found to be consistent with previous studies. In order to examine the existence of the EEJ associated meridional currents, we have estimated the vertical current density using combination of two satellites separated in longitude. [ABSTRACT FROM AUTHOR]

The doping effects of a small amount of RE (Gd and Ho) atoms at A (La) sites of La 2 NiMnO 6 double perovskite have been studied by preparing the materials using mechanical alloying of oxide powders and thermal treatment (800–1200 °C), and a direct sintering of the oxide powders at 1300 °C. The synchrotron x-ray diffraction patterns have been used to confirm the formation of single (monoclinic) phase or bi-phased lattice structure depending on thermal treatment temperature. The bi-phased samples are consisting of primary monoclinic phase (P 2 1 /n space group) and secondary orthorhombic phase (Pnma space group). The x-ray photoelectron spectroscopy has confirmed the presence of trivalent La, RE ions, and mixed-valence state of Ni and Mn ions in the samples. The existence of bi-phasic lattice structure and mixed-valence state of Ni and Mn ions have determined magnetic properties. The monoclinic phase has shown ferromagnetic Curie point around 280 K, which has been reduced to low temperature by Gd and Ho doping. The orthorhombic phase has shown weak ferro/ antiferromagnetic spin ordering temperature around 150 K. The experimental results in RE doped La 2 NiMnO 6 double perovskite support a strong correlation between lattice structure and magnetic properties, which depend on doping of RE ions at A sites, electronic charge state of Ni and Mn ions, structural phase components and anti-site disorder of Mn/Ni ions at octahedral sites. • Synthesis of Gd/Ho doped La 2 NiMnO 6 by mechanical alloying and solid state sintering. • A detailed analysis of structure, charge state of ions, and heat treatment effects on magnetism. • The heat treatment effect on coexisting monoclinic and orthorhombic phases in the samples. • Role of Ni-O-Mn bond structure and doping effect on ferromagnetic superexchange interactions. • Role of chemical inhomogeneity on bi-phased ferromagnetic properties and short range order. [ABSTRACT FROM AUTHOR]