44 research outputs found

    IJTC2008-71152 MISALIGNMENT EFFECT ON CEMENT KILN SUPPORT BEARING

    Get PDF
    ABSTRACT This paper illustrates the effect of misalignment on performance of cement kiln partial journal bearing. The performance parameters include minimum film thickness, load carrying capacity, power loss and dynamic coefficients such as elastic coefficients and damping coefficients. The bearing analyses have been carried out using a commercial rotor dynamics software package

    A comparative study of the histoarchitecture of endocrine pancreas in Labeo bata (Hamilton, 1822), Sperata aor (Hamilton, 1822) and Chitala chitala (Hamilton, 1822)

    Get PDF
    The disposition and cellular organization of the endocrine pancreas were studied in three species of freshwater teleosts viz., Labeo bata (Hamilton, 1822), Sperata aor (Hamilton, 1822) and Chitala chitala (Hamilton, 1822) using histological techniques. In L. bata, the endocrine pancreas tissues were mainly distributed in the adipose tissue among the intestinal coils and adjacent to extrahepatic bile duct, while in S. aor and C. chitala, the endocrine pancreas predominantly attached with wall of the stomach along with exocrine pancreatic part. Histological analysis demonstrated that the endocrine components of all the three species were enclosed in a thin capsule provided with different cells, interspersed with blood sinuses. The cytoarchitectural analysis showed that in L. bata, β cells were usually arranged in groups while α cells were often interspersed with blood vessels. In S. aor and C. chitala, the rounded or oval α cells were usually arranged either in groups or scattered to the islets periphery and β cells which were densely granulated and typically stained with Aldehyde fuchsin (AF), Romies azan (RA) and Mallory’s triple (MT) were observed in the central areas of the islets and intercalated with blood vessels. The δ like cells were founded at a low frequency and intermingled with β cells and exhibited moderate cytoplasmic granules in L. bata, S. aor and C. chitala. Despite being the subject of extreme controversy, the nature and function of different islet cells were discussed

    Practical aspects of electrophoretic deposition to produce commercially viable supercapacitor energy storage electrodes

    Get PDF
    Electrophoretic deposition (EPD) is a highly convenient and demonstrated industrial operation for the manufacture of surface coatings. Recent years are seeing increasing evidence in using this technique to produce energy storage electrodes (notably for lithium-ion batteries, solid-state devices, supercapacitors, and flow batteries), but their advancement for industrialisation remains unclear. Using activated carbon (AC) as an exemplary supercapacitor material, this study reports the practical aspects of porous energy storage electrodes produced by the EPD technique. Practical electrodes with commercially viable parameters are shown, specifically high density active material (in excess of 9.8 mg cm−2) and very thick coating layer (about 168 μm). Research investigations including colloidal electrolyte formulations, electrode deposition parameters and cell performance testing are reported. Materials and electrode properties were studied by various charactersisation tools. Prototype A7 sized pouch cells were assembled and tested to show evidence of practical EPD electrodes in a commercial cell format. Electrochemical performance of EPD over slurry casting is presented. In short, this research shows the successful production of practical EPD electrodes for electrochemical energy storage, which is directly relevant for scale-up industrial adoption and can be applied as a platform electrode manufacturing technology for any battery and supercapacitor materials

    Hydrogen/functionalized benzoquinone for a high-performance regenerative fuel cell as a potential large-scale energy storage platform

    Get PDF
    The redox flow battery (RFB) is a suitable option for electricity storage due to its high energy efficiency, scalability and relative safety. However, the limited metallic resources for redox materials and the high cost in systems such as the all-vanadium RFB are major challenges for wider application. Organics may be sourced more abundantly and have lower prices than metal based redox couples. In this work a regenerative fuel cell involving relatively inexpensive organic redox couples is demonstrated. The electrochemical properties of 1,2-dihydrobenzoquinone-3,5-disulfonic acid (BQDS) are characterised by cyclic voltammetry and linear-sweep voltammetry under hydrodynamic conditions. A regenerative fuel cell using 0.65 M BQDS in 1 M H2SO4 as positive electrolyte and gaseous hydrogen (1 bar) as negative redox-material results in an open circuit cell voltage of 0.86 V, a power density of 122 mW/cm2, and an energy density of 10.90 Wh L-1 without considering the volume occupied by the hydrogen. Very promising performance with an energy efficiency >60% at 100 mA cm-2 for 200 cycles is reported. New organic redox species resistant to side reactions could facilitate the use of this new system in practical applications. The use of hydrogen may also contribute to reduced side reactions of the organic redox associated with degradation in the presence of oxygen

    High prevalence of metabolic syndrome & its correlates in two tribal populations of India & the impact of urbanization

    Get PDF
    Background & objectives: Metabolic syndrome is one of the major causes of morbidity and mortality in the world. The prevalence of this syndrome is high among Asians, including Indians, and is rising, particularly with the adoption of a modernized life style. Whether traditional societies in India have a low prevalence and the extent to which a transition to a modern life style contributes to the increase in prevalence are unknown. To examine the role of environmental and genetic factors in metabolic syndrome we conducted a study in two sub-Himalayan tribal populations with shared ancestry (Toto and Bhutia). The Toto live exclusively in a rural area, whereas a section of the Bhutia has adopted a modern life style. Methods: Fasting (12 h) blood samples of Toto (n=258); rural Bhutia (n=75) and urban Bhutia (n=230) were collected, with written informed consent. Lipid profile, blood pressures, body fat and other anthropometric parameters were assessed. Criteria suggested by National Cholesterol Education Programme (NCEP) Adult Treatment Panel III (2001) were used for assessment of metabolic syndrome. Results: The prevalence of metabolic syndrome was high (about 30-50%) among the Bhutia, with no significant rural-urban difference. Among the Toto, though the prevalence of metabolic syndrome was low (about 4-9%), their lipid levels were alarmingly adverse (about 37-67% had low HDLcholesterol or high triglyceride levels). There was an additional adverse impact of adoption of urban life-styles (perhaps primarily mediated through dietary changes) on cardiovascular risk factors. Interpretation & conclusion: Our study suggested that metabolic syndrome and its correlates could be a major health problem even in traditional societies, indicating that this syndrome was not necessarily a result of modernization. Further, our study indicates that genetic factors that adversely affect the levels of such variables have long antiquities in Indian ethnic groups

    A cost-effective alkaline polysulfide-air redox flow battery enabled by a dual-membrane cell architecture

    Get PDF
    With the rapid development of renewable energy harvesting technologies, there is a significant demand for long-duration energy storage technologies that can be deployed at grid scale. In this regard, polysulfide-air redox flow batteries demonstrated great potential. However, the crossover of polysulfide is one significant challenge. Here, we report a stable and cost-effective alkaline-based hybrid polysulfide-air redox flow battery where a dual-membrane-structured flow cell design mitigates the sulfur crossover issue. Moreover, combining manganese/carbon catalysed air electrodes with sulfidised Ni foam polysulfide electrodes, the redox flow battery achieves a maximum power density of 5.8 mW cm−2 at 50% state of charge and 55 °C. An average round-trip energy efficiency of 40% is also achieved over 80 cycles at 1 mA cm−2. Based on the performance reported, techno-economic analyses suggested that energy and power costs of about 2.5 US/kWhand1600US/kWh and 1600 US/kW, respectively, has be achieved for this type of alkaline polysulfide-air redox flow battery, with significant scope for further reduction

    Interaction of Virstatin with Human Serum Albumin: Spectroscopic Analysis and Molecular Modeling

    Get PDF
    Virstatin is a small molecule that inhibits Vibrio cholerae virulence regulation, the causative agent for cholera. Here we report the interaction of virstatin with human serum albumin (HSA) using various biophysical methods. The drug binding was monitored using different isomeric forms of HSA (N form ∼pH 7.2, B form ∼pH 9.0 and F form ∼pH 3.5) by absorption and fluorescence spectroscopy. There is a considerable quenching of the intrinsic fluorescence of HSA on binding the drug. The distance (r) between donor (Trp214 in HSA) and acceptor (virstatin), obtained from Forster-type fluorescence resonance energy transfer (FRET), was found to be 3.05 nm. The ITC data revealed that the binding was an enthalpy-driven process and the binding constants Ka for N and B isomers were found to be 6.09×105 M−1 and 4.47×105 M−1, respectively. The conformational changes of HSA due to the interaction with the drug were investigated from circular dichroism (CD) and Fourier Transform Infrared (FTIR) spectroscopy. For 1∶1 molar ratio of the protein and the drug the far-UV CD spectra showed an increase in α- helicity for all the conformers of HSA, and the protein is stabilized against urea and thermal unfolding. Molecular docking studies revealed possible residues involved in the protein-drug interaction and indicated that virstatin binds to Site I (subdomain IIA), also known as the warfarin binding site

    Electrophoretic deposition of MXenes and their composites: toward a scalable approach

    No full text
    Over the past decade, MXenes, a novel class of advanced 2D nanomaterials, have manifested as a prominent electrode material with diverse applications. Their unique layered structures, negative zeta potential, charge carrier mobility, mechanical properties, adjustable bandgap, hydrophilicity, metallic nature, and surface chemistry collectively contribute to the abundance of active redox sites on the surface and a reduction in the ion diffusion pathway. Despite such promising attributes of MXene, challenges like aggregation and restacking reduce the accessibility of active surface sites for electrolyte ions. Amongst approaches such as surface functionalization, addition of spacers, or facilitating pore formation, the electrophoretic deposition (EPD) of MXene on substrates has commenced to gain attention aiming to mitigate these issues. More importantly, it offers large-scale film fabrication in a short time without the necessity of using a charge-inducing agent. This review compiles recent advances in the use of EPD for preparing MXene-based electrodes and discusses the effect of EPD parameters on the relevant device performance. Recognition is given to understanding the relation of MXene colloidal composition in aqueous (and in some cases, non-aqueous) dispersions, deposition times, and other relevant parameters on respective device performances. In conclusion, the potential avenues offered by MXenes for future research on electrode materials are emphasized
    corecore