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Electrochemical performance degradation of the air electrode due to the presence of trace levels of gaseous chromium impurities, a critical issue in high-temperature electrochemical systems, contributes to long-term irreversible performance instabilities. We report a low-cost getter comprised of SrO and NiO to capture extrinsic chromium impurities present in ambient air. Ceramic honeycomb-supported getters have been tested for 500 h under SOFC cathode exposure conditions and characterized by scanning electron microscopy–energy dispersive X-ray spectrometry and focused ion beam–transmission electron microscopy. Chemical and structural analyses show that gaseous chromium predominantly concentrates within ~ 4–5 mm at the air inlet, leaving only the remainder of the getter free of chromium. Chromium capture mechanisms are proposed and discussed based on experimental findings and thermodynamic calculations.

Fe and Ni base alloys serve as materials of choice for the fabrication of stack and balance of plant components in solid oxide fuel cell power systems. The oxidation behavior of select Fe and Ni base alloys has been investigated, and chromium evaporation rates have been experimentally measured at 850°C in 3% humidified air exposure conditions. Changes in the oxide morphology and chemistry from the alloys representing chromia former (602CA), alumina former (H214), and mixed chromia and alumina scale formers (AFA25) at 900°C and 1100°C during exposure to humidified air have been studied and are presented. It is found that the rate of Cr evaporation from the alloys decreases in the order of 602CA followed by Haynes 214 and AFA25 at 850°C during exposure to humidified air. Surface and cross-sectional scale morphologies and chemistry have been examined, and variations in the Cr evaporation behavior of different alloys are discussed based on the reaction thermodynamics.

Thermodynamic predictions were carried out on the phase stability of the lanthanum manganite (LSM)/yttria-stabilized zirconia (YSZ) system in presence and absence of Cr-containing dry and humidified atmosphere over broad ranges of temperature, oxygen partial pressure, and humidity. Formation of Mn oxides, La2Zr2O7, SrZrO3, Mn(Mn,Cr)2O4 (spinel), and zirconia was predicted, in agreement with previous experimental efforts. Humidity enhances the perovskite degradation by increasing the kinetics of secondary phase formation reactions. The impact of Cr6+ poisoning is more significant in presence of humidity in the atmosphere, as volatile Cr6+ species, in the form of CrO3 and CrO2(OH)2, may diffuse into the perovskite structure and change its phase stability and properties.

Contractile behavior of cardiomyocytes relies on directed signal propagation through the electroconductive networks that exist within the native myocardium. Due to their unique electrical properties, electroactive materials, such as graphene, have recently emerged as promising candidate materials for cardiac tissue engineering applications. In this work, the potential of three-dimensional (3D) nanofibrous graphene and poly(caprolactone) (PCL + G) composite scaffold for cardiac tissue engineering has been explored for the first time. The addition of graphene into PCL led to an increased volume conductivity of scaffolds with an even distribution of graphene particles throughout the matrix. Graphene particles provided local conductive sites within the PCL matrix, which enabled application of external electrical stimulation throughout the scaffold using a custom point stimulation device. When mouse embryonic stem cell derived cardiomyocytes (mES-CM) were seeded on PCL + G scaffolds, cells adhered well, contracted spontaneously, and exhibited classical cardiomyocyte phenotype confirming the biocompatibility of electroactive PCL + G scaffolds. Further functional characterization demonstrated that graphene especially affected Ca2+ handling properties of mES-CM compared to that of cardiomyocytes cultured in 2D culture, highlighting the potential of PCL + G for in vitro cardiac tissue engineering. © 2018 Wiley Periodicals, Inc. J. Biomed. Mater. Res. Part A: 106A: 2923-2933, 2018.

Solid oxide fuel cells (SOFCs) have the potential to meet the growing need for electrical power generation if the cost per megawatt can be further reduced. Currently, SOFC stacks are replaced too frequently to be cost competitive. SOFC service life can be extended by preventing chromium- (Cr-) bearing species from evaporating from the interior surfaces of balance of plant (BOP) components and poisoning the cathode to increase the lifetime. We have developed yttria-stabilized zirconia (YSZ) and aluminum oxide- (Al2O3-) modified sol-gel paints or inks for coating BOP components. 430 stainless steel (430SS) substrates with three surface conditions were coated with the 0.8–1.5 µm thick YSZ and Al2O3 paints. The coated 430SS samples were tested for thermal cycling resistance, thermal soak, and Cr evaporation. Thermal soak and thermal cycling test results show promise for the YSZ-coated 430SS substrates. The Cr evaporation test of a coated substrate showed a 51% reduction in Cr generation, when compared with a bare substrate.

The perovskite-type oxides, having a general formula ABO3, are promising candidates for anode materials in solid oxide fuel cells. In particular, doped SrTiO3 based perovskites are potential mixed ionic-electronic conductors and they are known to have excellent thermal and chemical stability along with carbon and sulfur tolerance. In this work, DyxSr1-xTiO3-δ system with x = 0.03, 0.05, 0.08 and 0.10 is studied to understand the influence of Dy content on its structural and electrical behavior. Electrochemical properties are measured, both in air and hydrogen atmosphere, and structural characterizations are performed before and after electrochemical tests and compared each other to study the stability. Results show that DyxSr1-xTiO3-δ powders with x ≤ 0.05, are single phase, while for x ≥ 0.08 a small amount of secondary phases is formed. In air, the conductivity is predominantly mixed ionic-electronic type for x ≤ 0.05, becoming ionic for x ≥ 0.08. It is observed that conductivity, for each composition, increases passing from air to hydrogen and activation energy decreases. Dy0.05Sr0.95TiO3-δ shows the highest conductivity in air whereas Dy0.08Sr0.92TiO3-δ in H2 atmosphere. Degradation observed by XRD is negligible for x ≤ 0.05 but increases with higher Dy content.

The objective of the present study was to characterize intrinsic physiological and biochemical properties of the wall-less unicellular cholorophyte Dunaliella salina isolated from a hypersaline Sambhar Lake. The strain grew optimally at 0.5 M NaCl and 16:8 h L:D photoperiod along with maintaining low level of intracellular Na+ even at higher salinity, emphasizing special features of its cell membranes. It was observed that the cells experienced stress beyond 2 M NaCl as evidenced by increased intracellular reactive oxygen species and antioxidative enzymes, nevertheless proline and malondialdehyde content declined sharply accompanied by higher neutral lipid accumulation. Salinity exceeding 2 M resulted decrease in photosynthetic quantum yield (Fv/Fm) and enhanced glycerol synthesis accompanied by leakage. Super oxide dismutase seemed to play a pivotal role in antioxidative defense as eight isoforms were expressed differentially while catalase and glutathione peroxidase showing no significant change in their expression at higher salinity. The ability of D. salina to grow in range of salinities by sustaining healthy photosynthetic apparatus along with accumulation of valuable products made this alga an ideal organism that can be exploited as resource for biofuel and commercial products.

In this work, a universal path independent integral Ju that represents the energy release rate or flux during crack extension in a homogeneous and isotropic material, has been derived for straight crack subjected to multiple loads. This version of integral includes the effect of elastic strain, Eigen strain, thermal strain, body forces and magnetic strain. Particularly focus is made on thermo-mechanical and magnetic strains. The 3D J-integral expression represents the energy release rate in the combined thermoelastic field with magnetostriction characteristics. This integral is applicable to the real field problems concerning medium in an electric field where the multiphysics of heat generation and magnetic field are involved. 3D finite element analysis of edge cracked magnetostrictive specimen has been carried out to demonstrate the efficacy of the integral expressions.

In the present paper, a microstrip line fed compact monopole printed antenna is designed for Bluetooth, WLAN and WiMAX applications. The designed antenna has a compact size of dimensions 34 × 20 × 1.6 mm3. The proposed antenna comprises asymmetric U-shaped radiator embedded with a T-shaped strip in the middle of the patch. Stair shaped defected ground plane with rectangular slit is used for the bandwidth enhancement. The antenna design achieves the maximum impedance bandwidth of 107.35% (2.27–7.53 GHz). Radiation efficiency is higher than 70.0% throughout the entire operating band. The simulated and measured realised antenna gains are in good agreement and vary in the range of 2.14–4.83 and 2.20–4.91 dBi respectively. Radiation patterns are almost omnidirectional in H-plane and bidirectional pattern in E-plane. The antenna characteristics are calculated using CST Microwave Studio and the results are compared with the measured results.

I argue that contextually reading two disputes involving Siam—Cheek v. Siam (1898) and the Temple of Preah Vihear (1962)—proves that both private law and public international law are structurally rigged against ex-semi-colonial nations. Nineteenth-century Siam was a political ferment known variously as a semi-colonial, semi-peripheral, non-colonial, or uncolonized polity. Siam bargained under imperial shadows her political independence by the tactical grants of concession contracts, as well as by negotiating treaties with competing European powers. In the post-colonial Temple of Preah Vihear case, colonial stationery—maps, photographs, and communiqués—as well as imperial customs offered evidentiary support to Cambodia, an ex-colonial state, against Thailand. In the early twentieth century, while authors picked Cheek v. Siam as a precedent for the law of international claims, textbooks offer the Temple of Preah Vihear case as a precedent on the form of treaties and estoppel. Conclusively, these two cases allow us to locate, if not exorcise, the ghosts of empires in Asian legal history, exposing, at the same time, Judge Koo’s Orientalization of customary international law.

Yttrium (Y3+) doped strontium titanate (YxSr1-xTiO3-δ with x = 0, 0.03, 0.05, 0.08 and 0.10) was synthesized via citrate-nitrate auto-combustion route. The electrical and structural properties of the prepared compositions were investigated to check their suitability as anode material for SOFC application. The XRD patterns of synthesized specimens showed single phase having a crystal structure similar to that of the undoped SrTiO3. Trace amounts of secondary phase were observed in compositions with x ≥ 0.05. The FESEM micrographs of all compositions revealed a non-monotonous behaviour of grain size in YxSr1-xTiO3 system with YST8 as most porous sample among all prepared compositions. The oxygen content in the specimens was also confirmed through XPS analysis. The conductivity values in air and H2 atmosphere were obtained from Nyquist plots in the temperature range of 100–700 °C. From a systematic study, the conduction mechanism was explained on the basis of defect chemistry. Moreover, the chemical stability of samples was checked through XRD patterns with corresponding FESEM micrographs after the conductivity measurements in H2 atmosphere. Results showed that amongst all the prepared samples, Y0.08Sr0.92TiO3 may be proposed as a promising composition as anode material for SOFC application.

In this paper, a scarecrow-shaped ultrawideband (UWB) antenna is presented using CPW and microstrip line feeding. The physical dimensions of the proposed antennas are $$25 \times 20 \times 1.6\,\hbox { mm}^{3}$$ , in which the modification in the ground is made by etching two half-circle and square slots symmetrical with respect to center feed line. The measured impedance bandwidth (return loss $$

The paper argues for conflating refugees and internally displaced persons (IDPs) as two sides of a work-in-progress postcolonial state. To be sure, aliens, refugees, IDPs, and stateless persons are separate legal entities. Nevertheless, this fragmented normative regime stands testimony to more laws and less justice. Many Asian states have no domestic refugee law. India, a common law system, takes a case by case approach as refugees are given “temporary shelter on humanitarian considerations”. Ironically, a work-in-progress postcolonial state sustains even de jure citizens as de facto stateless persons; the erstwhile Indo-Bangla enclaves for more than half a century were an apt example. Surely, the raison d’etre of international law on refugees is to end human suffering, if needed, by transcending the absence of positive laws. A constitutional and political desire to minimise human suffering alone could cut the rigour of such positivist legal narratives. The Delhi High Court seemingly walked that path in Koul v Estate Officer noting “refugees and IDPs appear to be similarly situated”. Rising terrorism has made states increasingly believe in a security narrative all the same. A simultaneous emergence of a demographic anxiety particularly in India’s North-eastern states increasingly pits aliens and refugees against the domiciled indigenous and tribal people.

Electrochemical splitting of water, using solid oxide electrolysis cells (SOEC), offers an economic and efficient pathway for large-scale hydrogen production that not only utilizes renewable energy but also allows both distributed and centralized hydrogen production to accelerate and enable hydrogen infrastructure for mobility. In this technical contribution, two types of electrochemical systems using conventional oxygen ion conducting (O-SOEC) and newly developed proton conducting (P-SEOC) has been compared in terms of hydrogen purity, electrochemical performance, and stability (structural and electrochemical). The observations on dopant exsolution, solid-solid (electrode/electrolyte interface) and solid-gas (electrode-H2O, O2, and H2) interactions have been presented. The composition, structure, and morphology changes and their roles on electrochemical performance and electrode stability in oxidizing (O2) and reducing (H2) atmospheres has been discussed.

In this work, we report the synthesis of cuprous oxide (Cu2O) nanoparticles modified vertically oriented aligned titanium dioxide (TiO2) nanotube arrays through wet chemical treatment of TiO2 nanotubes and their multi-functional application as enhanced photo electrochemical and hydrogen generation. The synthesized samples were characterized by X-ray diffraction, SEM, TEM, and UV–Vis spectroscopy. The structural characterization revealed that the admixed Cu2O nanoparticles on the TiO2 surface did not alter its crystalline structure of vertically oriented aligned TiO2 nanotube. The photocatalytic performance and hydrogen generation of as synthesized Cu2O nanoparticles modified aligned TiO2 nanotube was found to highly depend on the Cu2O content. The optical characterizations reveal that the presence of Cu2O nanoparticles extends its absorption into the visible region which improves the photocurrent density in comparison to pristine aligned TiO2 nanotubes electrodes due to enhanced photoactivity and better charge separation. The optimum photocurrent density and hydrogen generation rate has been found to be 3.4 mA cm−2 and 127.5 μmole cm−2 h−1 in 1 M Na2SO4 electrolyte solution under 1.5 AM solar irradiance of white light with illumination intensity of 100 mW cm−2.

The surface morphology and chemistry of oxide scales formed on select chromia-forming and alumina-forming ferritic steels have been studied after exposure to a dual atmosphere of hydrogen and air. Localized Fe-rich oxide nodules with surface whiskers/platelets form at the onset of corrosion. The initiation and growth of localized nodules and breakdown of passivation are attributed to the presence of hydrogen, inclusion of iron oxide in the passivating scale, and subsequent growth of iron-rich oxide due to the establishment of redox (H2-H2O) atmosphere and modification of oxide defect chemistry.

Fusarium species are among the most commonly isolated causes of fungal keratitis. Most species of the genus Fusarium belong to Fusarium solani species complex (FSSC). Fusarium lichenicola, a member of the FSSC complex, is a well-established plant and human pathogen. However, reports of fungal keratitis due to Fusarium lichenicola have not been frequently reported. To the best of our knowledge, only twelve cases of Fusarium lichenicola keratitis have been reported in the past fifty years. Clinical cases of Fusarium lichenicola may have most likely been misidentified because of the lack of clinical and microbiological suspicion, as well as inadequate diagnostic facilities in many tropical countries where the burden of the disease may be the highest. We report a case of fungal keratitis caused by Fusarium lichenicola and present a global review of the literature of all cases of fungal keratitis caused by this potentially blinding fungus.

Long-term corrosion behaviors of molten carbonate fuel cell (MCFC) electrolyte matrix with LiAlO2 particle coarsening are evaluated in eutectic Li-Na carbonate melts with different pCO2. In low pCO2 (basic), the rapid growth of LiAlO2 particles by Ostwald ripening is observed. TEM analysis verifies the continued process of dissolution and precipitation of LiAlO2 nanocrystals that promotes LiAlO2 crystal growth. It is revealed that this growth process is accompanied by α–γ phase transition through a Li5AlO4 intermediate phase. In high pCO2 (acidic) conditions, oriented attachment, primarily between the (003) and (012) planes of α-LiAlO2 crystals, leads to interparticle coalition and growth.

The paper presents a simplistic way to synthesize NaSr(1−x)VO4:xMn2+ nanophosphors with 0.25 ≤ x ≤ 3.0 mol% by using combustion synthesis route in which urea is used as an organic fuel. The structural, spectral and optical properties were examined using XRD, UV–Vis spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Photoluminescence (PL) spectroscopy. Doping the host with Mn2+ ions created the mid gap absorption phenomenon. Initially, a red shift is observed in the band gap for low amount of the transition metal ion Mn2+ in NaSrVO4 host which is followed by an augment in the band gap values for higher concentrations. Photoluminescence properties shows that under excitation at 380 nm, sample possess two prominent emissions peaking at 434 nm and 523 nm. This phosphor material may possibly be considered of as a new material to be excited by UVA emitting InGaN LEDs.

We aim to highlight the ignorance and incidences of deliberate hiding of medical facts in society. The cause of it can be, the associated taboo with these diseases. The fear of social outcasts is the major barrier preventing diseased from accepting the diagnosis as well as treatment. Though the medical facility has improved significantly and has come up with a complete cure for these diseases, still these facilities are not able to trickle down to the lower socioeconomic group. The reason for facilities not reaching the lower socioeconomic strata is the self-made shield created by these people. The current case report tries to highlight the need to screen the family members and the contacts of patients with tuberculosis. The screening should be done holistically and thoroughly to rule out extrapulmonary pulmonary disease also.

A comprehensive thermodynamic study by applying the CALculation of Phase Diagram (CALPHAD) approach on (La 0.8 Sr 0.2 ) 0.98 Cr x Fe 1 − x O 3 ± δ (x = 0.3, 0.5, 0.7) (LSCrF) has been carried out to investigate the effect of atmosphere, temperature, and B-site dopant concentration on phase stability, solid and liquid phase formation, and microstructural evolution in LSCrF. The simulation results for the chemical stability of LSCrF, exposed to oxygen partial pressure (PO 2 ) from 0.21 to 10 − 10 atm and temperature from 1000 to 1400 °C, reveal the formation of solid corundum, spinel, La 2 SrFe 2 O 7 , and the liquid phase. The simulations also show the chemical reactions of solid secondary phases with the liquid and perovskites under both equilibrium cooling and fast cooling conditions. The phase stabilities of the LSCrF samples under oxygen transport membrane (OTM) sintering and operation conditions are predicted. The study provides guidance on the densification enhancement of the LSCrF bulk materials during the sintering process through the control of the liquid phase concentration and the perovskite phase separation. In addition, the concerns of the release of the genotoxic carcinogens, i.e. chromium hexavalent (Cr 6 + ) gas species from LSCrF to the environment under the sintering and operation conditions are addressed for the first time.

The present research, as a part of the OTM materials development and testing effort, examines the combined effect of the Cr: Fe ratio (7:3, 8:2 and 9:1) and oxygen partial pressure (PO2) on the densification, microstructural development, and chemical stability of lanthanum chromite (La0.8Sr0.2)0.95Cr1-xFexO3 (LSCrF) for application in oxygen transport membrane and solid oxide fuel cell electrode. While highest density of 96.3 (±0.5) % is achieved for LSCrF with Cr: Fe ratio of 7:3 at 1400 °C and PO2 ∼ 10−10 atm., the relative density decreases with increase in Cr: Fe ratio and PO2. LSCrF perovskite stability increases with increase in Cr: Fe ratio in reducing gas atmosphere. LSCrF (7:3) dissociates into FeOx and Fe1+xCr2-xO4 under reducing gas atmosphere (Ar-3%H2-3%H2O). LSCrF (9:1) perovskite does not show any evidence of second phase (FeOx and Fe1+xCr2-xO4) formation with decrease in PO2 unlike LSCrF (7:3 and 8:2). Defect chemistry and mechanism for FeOx and Fe1+x Cr2−x O4 formation in reducing atmosphere is described. LSCrF decomposition and the formation of the secondary phases are in agreement with the thermodynamic simulation results obtained with the La-Sr-Cr-Fe-O thermodynamic database.

Yttria-stabilized zirconia (YSZ) is a common solid electrolyte for solid oxide fuel cells (SOFCs) because of its high electrical conductivity and high ionic transference number in both oxidizing and reducing atmospheres. Samarium doped ceria (SDC) has also been considered as an alternative electrolyte material to YSZ for intermediate temperature SOFC because of its high conductivity at relatively low temperatures. Due to improved ionic conductivity of YSZ at high temperature (~ 800 °C) and good conductivity of SDC in the intermediate temperature range (600–800 °C), the electrical properties of YSZ-SDC composites were investigated. Composites of YSZ and SDC with weight ratio 9.5:0.5, 9:1 and 8.5:1.5 were synthesized via glycine-nitrate route. XRD pattern of the systems revealed the formation of composite phases. Biphasic electrolyte microstructures were observed, in which SDC grains are dispersed in YSZ matrix. Relative density of the compositions was found to be more than 92% to the theoretical density. It was observed that the interface provides a channel for ionic transport, leading to a notable ionic conductivity. With increase in SDC weight ratio the electrical conductivity was found to increase. For weight ratio 8.5:1.5 the electrical conductivity was found to be greater than that of YSZ in the temperature range 400–700 °C. Further, for weight ratio more than 8.5:1.5, conductivity was found to decreases due to the formation of a few other insulating impurity phases. The electrode polarisation was also found to reduce significantly with SDC in the composite electrolyte system. Thus, such composite system may be useful for improving the ionic conductivity of the composite electrolytes.

Solid oxide fuel cell (SOFC) systems provide efficient and clean power. Chromium poisoning is known to deteriorate the performance of the SOFC cathodes such as La1−xSrxCoO3 (LSCO) due to the formation of undesired products. We identify the reaction products when LSCO is in a CrO3 and O2 atmosphere using first principle thermodynamics, with the assumption that gas-phase CrO3 is the Cr source. Our results correctly identify SrCrO4 as the primary Cr poisoning product as observed in experiments and also provides temperature-pressure regimes under which Cr poisoning effects may be avoided.

In this paper, a modified L-strip fed patch antenna is theoretically analyzed for wideband applications. Dual U-shaped slots are incorporated in the radiating patch and a maximum bandwidth of 16.93% (2.65 GHz to 3.14 GHz) is achieved. Further, when two parasitic elements are used, antenna bandwidth improves up to 25.89% (2.90 GHz to 3.77 GHz). The maximum gain of dual U-slotted patch and with parasitic elements is 8.23 dBi and 8.46 dBi respectively. Antenna parameters are calculated by CST Microwave studio and equivalent circuit model theory is presented. The proposed antenna is fabricated and the measured results compare well with the theoretical as well as simulated results.

Solid oxide electrolysis cells (SOECs) of configuration La0.85Sr0.15Cr0.2Co0.1Ti0.7O3-δ (LSCCT)//ScSZ//GDC-LSM have been fabricated and electrochemically tested for the electrolysis of CO2 and H2O. Performance of the cell has been compared with standard Ni-SDC/ScSZ/GDC-LSM cell. EIS results show that LSCCT//ScSZ//GDC-LSM cell has higher non-ohmic resistance than the standard cell in 5% H2-CO2 containing environment. However, Cu impregnation of the LSCCT cathode using wet impregnation technique results in significant reduction in the non-ohmic resistance. Decrease in the thickness of the LSCCT cathode also reduces both ohmic and non-ohmic resistances. With the applied electrolysis voltage of 1.6 V at an operating temperature of 800 °C, the cell exhibited stable performance in 5% H2O/CO2 for more than 50 h with the electrolysis current density of 0.45 A.cm-2. Post-tested LSCCT cathode showed no carbon deposition whereas standard cell showed filamentary carbon formation and pulverization. Observations pertaining to surface (gas – electrode) and interface (electrode – electrolyte) will be presented.

Cr poisoning has been identified as a leading cause for degradation of solid oxide fuel cells. Mitigation can be achieved by protective coatings such as Mn-Co spinel or aluminization on ferritic stainless steel, a leading candidate for metallic interconnect. This has been successfully demonstrated in short and medium term operation, although the long-term integrity of these coatings remains to be validated. In addition to the passive means for Cr mitigation via protective coatings, Pacific Northwest National Laboratory has teamed with University of Connecticut to adopt an active means to tackle the issue by including a novel Cr-getter material in the system. A novel Sr-Ni-oxide developed at University of Connecticut as Cr-getter has proven promising in small button cell testing. In this work, commercial YSZ/NiO anode-supported YSZ cells (50 mm x 50 mm) with either LSCF or LSM cathode were tested in a generic stack test fixture using humidified (~4.75%) air and diluted hydrogen. Two Cr-getter locations were investigated: one upstream of the cell and one “on cell.” Pre-oxidized AISI 441 metal stripes were used as the Cr source. In this study, we validated the candidate Cr-getter materials made either by a nitrate solution method or the solid-state reaction method. Candidate getter materials from nitrate solution approach were impregnated into a porous alumina form, while getter materials obtained by solid state reaction were sintered into small cylinders. For comparison, plain cells with and without a Cr source were also tested to provide baseline data. All cells were tested at constant current for ~1000h at 800oC. Cell performance and impedance were recorded, followed by post-mortem optical/electron microscopy and cathode microstructure/composition analysis. The results showed promising gettering performance with no Cr detected within cathode areas.

Cost effective alkaline earth and transition metal complex oxides (SrxNiyOz) have been synthesized and electrically tested as chromium getter to mitigate Cr poisoning in solid oxide fuel cell (SOFC) power generation systems. In this study, we report the chemical and structural stability of the SrxNiyOz powder under simulated synthesis and operational conditions. High temperature in-situ X-ray diffraction (XRD) has been used to determine the phase stability of SrxNiyOz in the temperature range of 850 °C to 1000 °C while SEM-EDS technique was used to study the surface morphology and elemental distribution in bulk phases. XRD results indicate that the synthesized SrxNiyOz remains stable at 850 °C and 900 °C with no/negligible phase separation of SrO and NiO compounds, whereas exposure to temperatures 950 °C and 1000 °C leads to the decomposition of parent phase and formation of SrO and NiO. Further, it was observed that the powder samples sintered at 950 °C and 1000 °C showed volume expansion and pulverization when exposed to the humid air atmosphere for 24h. Samples sintered at 850°C and 900°C maintained structural stability and shape.

Low-Temperature Solid Oxide Fuel Cells (LT-SOFCs), operating in 500-700 °C temperature range on fossil derived hydrocarbon fuels, are widely viewed as the “next generation” of clean and efficient electrochemical power generation technology that may also remain prone to gaseous chromium assisted cathode poisoning. Chromium poisoning of strontium doped lanthanum manganite (LSM) and lanthanum strontium cobalt ferrite (LSCF) cathodes have been studied in half-cell configuration at 650 °C in gaseous chromium vapor containing humidified air. The electrochemical performance of LSM/YSZ/Pt half-cell shows faster degradation in chromium containing air with a rapid change in the polarization resistance compared to LSCF/GDC/Pt half-cell. Electrode chemistry, morphology and elemental distribution have been studied using Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Analysis (EDX) and X-ray Diffraction (XRD) techniques. A thermodynamic analysis of the degradation process was also conducted. Our observations show that lowering of cell operating temperature may not significantly lower the cell performance degradation. Possible approaches for mitigating above degradation will be discussed.

A few compositions of La doped strontium titanate, LaxSr1−xTiO3−δ (x = 0.0, 0.1, 0.2, 0.3, and 0.4) were synthesized via solid state reaction route. The XRD patterns of the compositions with x ≤ 0.2 showed single phase whereas for x ≥ 0.3 compositions, secondary phases were observed. The Rietveld refinement of the XRD data for all compositions indicated cubic structure with space group Pm 3 ¯ m at room temperature. The SEM micrographs for x = 0.0 showed large grains, whereas the compositions with 0.0

Chemical and structural stability of strontium doped lanthanum manganite (LSM) and lanthanum cobalt ferrite (LSCF) cathodes in Cr-containing humidified air has been studied by a combination of experimental and thermodynamic approaches. During 100 h tests performed in flowing air (3% H2O) at 1023 K, the electrochemical performance of LSM/yttria doped zirconia (YSZ)/Pt half-cells exhibited a relatively faster degradation in current (I–t) at 0.5 V applied bias than the LSCF/gadolinium-doped ceria (GDC)/Pt half-cells. Cr species from the gas phase deposited predominantly at LSM/YSZ interface while LSCF showed mainly surface deposition throughout the electrode. Raman spectra indicate SrCrO4 formation on the post tested LSCF cathode but not on the post tested LSM cathode. The polarization resistance of the LSM cathode also increased significantly compared to that of the LSCF cathode. A linear programming approach coupled with first-principles thermodynamics suggests that the stoichiometric LSM remains stable and unreacted for the whole range of experimental PCrO3 and temperature conditions whereas the formation of SrCrO4 on LSC cathode is energetically favored at 1023 K supporting the experimental findings.

Effect of oxygen partial pressure (PO2) on the processing and phase evolution in (La0.8Sr0.2)0.95Cr0.7Fe0.3O3 (LSCF) is investigated under high temperature electrochemical device fabrication conditions at 1400 °C and oxygen partial pressure (PO2) varying from 0.21 to 10−10 atm. Formation of Fe enriched phase is identified in the samples exposed to reducing atmosphere and the amount of the phase increases with decrease in PO2. LSCF dissociates and forms FeOx when exposed to Ar-3%H2-3%H2O at 1400 °C. LSCF decomposition and the formation of FeOx is in agreement with the thermodynamic simulation results obtained using ThermoCalc with the La-Sr-Cr-Fe-O thermodynamic database. Electrochemical impedance spectroscopy measurement on the symmetrical cell of configuration LSCF-YSZ/YSZ/LSCF-YSZ shows high polarization resistance in oxidizing atmosphere when compared to reducing atmosphere under operating conditions (T ∼ 950 °C and PO2 ∼ 0.21–10−16 atm). No degradation and microstructural changes are identified in the samples exposed to air for 80 h. Surface of LSCF phase is significantly modified in Ar-3%H2-3%H2O atmosphere after electrochemical testing for 80 h. Higher stability and electrochemical performance of LSCF is obtained in air when compared with Ar-3%H2-3%H2O. Unlike oxidizing atmosphere, post characterization TEM results show thin SrZrO3 layer formation at the LSCF/8YSZ interface in reducing atmosphere.

In the present work, the glass systems 0.70TeO2–0.30MO and 0.65TeO2–0.35MO (M = Ba, Sr) were prepared and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, UV–vis spectroscopy and differential scanning calorimetry. The structural studies show that amorphous alkaline tellurite glasses are made up of vibrational units of molecular water group, hydroxyl bonding, symmetrical stretching vibration of Te–Oax bonds in the deformed TeO4 and stretching and bending vibration of Te–O–Te linkages in TeO4/TeO3 + d polyhedra/TeO3. In the X-ray diffractograms, shifting of amorphous peak was observed towards higher angle side with the strontium substitution in comparison to barium substitution due to lower ionic radii. The optical band gap of investigated glasses was found to lie in the range 2.94–3.31 eV and was found to be lower in SrO added glasses than that of BaO added glasses. This may be due to the presence of more number of non-bridging oxygen in Sr substituted glasses than Ba substituted glasses. The Ba substituted samples were observed to be denser than Sr substituted glasses. Ultrasonic longitudinal and sheer velocities were found in the range of 3160–3210 and 1785–1850 m/s, respectively and were observed to be higher in Ba substituted glasses. The ac conductivity spectra were found to follow Jonscher power law and conduction mechanism is governed by overlapping large polaron tunneling model created with non-bridging oxygen and Tellurium ions.

Background Inflammation in the affected region, increased intracranial pressure, consequent oedema and congestion contribute to the negative outcome of traumatic brain injury. Osmotic therapies are recommended for improvement in cognitive and motor functions. Aim of the present study was to evaluate the effect of osmotic therapies in a mice model of traumatic brain injury. Methods Experimental closed head injury was performed in adult Swiss albino mice by the weight-drop method. Different group of animals were treated with normal saline (G1), mannitol (G2), mannitol + glycerin (G3) and Neurotol (G4). Neurological Severity Score (NSS) was recorded at different time-points upto a period of six days. Effect of treatments on cerebral oedema, learning and memory function, motor function and co-ordination were evaluated by gravimetry, Morris water maze and beam walk test respectively. Histopathology was performed to evaluate the treatment effects on microscopic complications arising from primary closed head injury (CHI). Results All the treatments showed a marked improvement in the evaluated parameters as compared with the vehicle control group. It was evident that G3 and G4 had a distinct advantage over mannitol therapy. Based on the NSS score, Neurotol proved to be comparatively safe and more efficacious than either mannitol or a combination of mannitol + glycerol. The effect of Neurotol could have been enhanced by the presence of VRP011 (a Mg +2 salt). Conclusions Neurotol is safe and exhibits better efficacy as compared with other treatments for the management of traumatic brain injury.

Chromium evaporation, from chromia forming ferritic alloys used in interconnect (IC) and the low cost iron and nickel base alloys used in balance of plant (BOP) during exposure to ambient air, and subsequent interactions of gaseous chromium species with the cathode is considered as one of the leading causes for the long term irreversible performance degradation in SOFC power generation systems. Although, surface coatings and alloy modifications have proved helpful in providing near term solution for the mitigation of chromium poisoning, the aforesaid remain susceptible to structural degradation in long term. A novel approach for mitigating cathode degradation by capturing gas phase chromium vapor from the air stream has been developed. Results from transpiration and symmetric electrochemical tests, conducted under simulated SOFC systems operating conditions, will be presented. Underlying thermodynamic and electrochemical processes associated with chromium evaporation and subsequent interactions with getters will be presented.

This paper reports a comparative assessment of the chemical and structural stability of LSCM perovskite composites fabricated with 8YSZ and 10ScSZ. Role of oxidizing and reducing atmospheres are examined on the processing and electrochemical performance of the composites. Higher density is obtained during the sintering of LSCM mixed with 10ScSZ when compared to composite mixtures containing 8YSZ in oxidizing as well as reducing atmosphere. Above composites also densified more in Ar-3%H2-3%H2O atmosphere than air along with the formation of SrZrO3 in reducing atmosphere. MnCr2O4 formation is found only in LSCM-8YSZ composite in Ar-3%H2-3%H2O. Electrochemical tests conducted using symmetric cell configurations indicates low polarization resistance and higher performance for Gas (air/fuel)/LSCM-10ScSZ//8YSZ/LSCM-10ScSZ/Gas (air/fuel). Unlike cell containing LSCM-8YSZ composite, no significant changes are identified in the polarization resistance of LSCM-10ScSZ cell for 80 h. Sr-segregation on the surface of LSCM in electrically tested LSCM-8YSZ cell is attributed to performance degradation in the reducing atmosphere.

Professor RP Anand analysed the birth of new states and their theoretical and functional inclusion in the post-UN world. The 1947 Indian independence afforded Indian lawyers a choice between Nehruvian internationalism and Judge Pal’s Tokyo dissent. Essentially, Anand preferred state interest over cultural differences as the currency of international law while celebrating the UN Charter, the International Court of Justice, and the UN Convention of the Law of Sea as the achievements of the mankind. Anand saw the rejection of international law as synonymous with power politics. While optimistic, his universalism engendered a Western anti-thesis that an Asian approach to international law, if any, was otiose. Subsequently, post-colonial scholars responded with a synthesis that brought colonialism from periphery to the centre of international legal theory.

A compact and multiband planar antenna is proposed which exhibits circular polarization (CP) characteristics. The microstrip line fed antenna consists of three unequal parallel slits in the patch. The overall dimension of the proposed design is $19.5\times 21.5\times 1.6\ \mathrm{mm}^{3}$ , A strip of dimension $8.5\times 3\ \mathrm{mm}^{2}$ is attached with ground plane to obtain CP characteristics. The measured multiple bandwidths are varying from 4.19-7.25 GHz (53.50%), 9.25-9.49 GHz (2.56%), and 11.28-13.63GHz (18.87%) and also the axial ratio bandwidths are obtained for this antenna are 36.52% (4.79-6.93GHz), 1.68% (11.24-11.43 GHz), respectively. The radiation properties, reflection coefficient, gain, and radiation efficiency are calculated for its useful implications in wireless systems. The proposed investigations are validated with the experimental data.

Microgrid (MG) system has a vital role in fulfilling the ever increasing electricity demand in the continuously expanding power systems. Significant power can be integrated from Renewable energy sources such as solar, wind and small hydro to MG systems. MG may a distribution power network of either low voltage level or medium voltage level consisting of various energy sources from distributed generations (DG’s) such as photovoltaic system, fuel cell, biomass, wind, small hydro, energy storage systems, etc. MG can be a single controllable system which can be operated in islanded mode without connecting to main grid or grid-connected mode. This study presents the design of MG system based on a given load data and available resources for minimum cost of energy, maintenance and replacement. The design is carried out using HOMER Software so as to maximize the energy usage from the DG’s instead of grid supply to meet most of the load demand in the MG system. The study presents an approach to an efficient MG system design based on available renewable power generation units for the most efficient distributed energy sources and optimum ratings of the components required to meet the load demand of a known local area. It also presents the techno-economic feasibility study of the MG system so designed. The simulation results and discussions are presented.

Sensitivity and reliability of animal behavioral assessment methods are critical for successful translation of in vitro findings to in vivo. Here we report a data transformation process in the elevated open platform task that generates a novel parameter, namely peak tolerance of fear (PTF) or its inversely correlated equivalent of anxiety quotient (AQ), to measure anxiogenic tendency in rodent. As compared to traditional parameters such as travel distance, time, or entries, PTF or AQ displays largely reduced data dispersion not only ingroup but also cross-study and cross-cohort, therefore representing a significant improvement of the methodology for rodent anxiety assessment.