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In this study we investigate the effect of deep cryogenic treatment (DCT) on a high-alloyed ferrous alloy (HAFA) to understand the resulting chemical and physical changes to the HAFA's microstructure and properties. Using multiple materials analysis techniques, we uncover the fundamental chemical changes to the HAFA with DCT, and link changes in material properties to changes in the microstructure. The increased carbide nucleation with DCT is linked to greater solute mobility resulting from the modified stress state of the material and modified chemical bonding of the solutes with the matrix. In turn this provides the possibility of prior formation of nucleation points for primordial carbide formation that act as accelerators for both nucleation and evolution of carbides. These result in modified chemical and microstructural homogeneity of the material that fundamentally led to changes in the surface properties and applicability of HAFA in advanced wear, corrosion and fatigue resistance demanding conditions.

It is well known that the Al2O3coating of the LiMn2O4cathodes leads to improvement of the performance of these electrodes. However, the effect of the coating on the fundamental processes occurring on the interface with the active material which results in the formation of the solid permeable interphase is yet to be investigated. These effects should be more pronounced in the first cycle when a dynamic interaction of the active material at high voltage with the electrolyte and binder leads to the formation of this passivation layer. Here, we present a detailed investigation of the solid permeable interphase formation in alumina-coated and uncoated LiMn2O4electrodes using X-ray absorption spectroscopy and analysis on the electrodes at the predesigned charging/discharging states. We demonstrate that the alumina coating leads to modification of the solid permeable layer and its dynamics. We also discuss the possible influences of interface modifications via coating on the battery performance.

The authors present a summary of their understanding of the publications that appeared in the computing literature during the last five-year period, with the word quality as part of their title and dealing with some or other aspects of software quality assurance. Specifically, the summary covers the following eight sub-topics, viz., (i) quality models; (ii) timely QA feedback; (iii) quantitative approaches to predicting software quality and the effectiveness of software QA; (iv) optimal choice of QA methods; (v) design level QA; (vi) impact of parallel development options on software quality; (vii) continued QA efforts even after the operational deployment of the software product; and (viii) use of CASE tools and perceived value for QA at NASA JPL. This digest also includes summaries of three short papers describing ongoing research on (i) prioritizing QA efforts; (ii) QA in an Agile development context; and (iii) presenting the software quality status to stakeholders during development. Major trends observed in the summary pertain to (i) continuing software QA efforts even after the operational deployment of the software product, which may also be pertinent to the proliferation of mobile applications; (ii) presenting the current software quality status to different stakeholders using concise sets of software metrics; and (iii) the effectiveness of hybrid approach of tool use combined with expert judgment for software QA. The emphasis on software QA activities spreading throughout the software product life cycle, from its beginning to end, is clearly observed in the reviewed literature.

Abstract: Characteristics of trace gases (O3, CO, CO2, CH4 and N2O) and aerosols (particle size of 2.5 micron) were studied over the Arabian Sea, equatorial Indian Ocean and southwest part of the Bay of Bengal during the monsoon transition period (October–November, 2004). Flow of pollutants is expected from south and southeast Asia during the monsoonal transition period due to the patterns of wind flow which are different from the monsoon period. This is the first detailed report on aerosols and trace gases during the sampled period as the earlier Bay of Bengal Experiment (BOBMEX), Arabian Sea Monsoon Experiment (ARMEX) and Indian Ocean Experiments (INDOEX) were during monsoon seasons. The significant observations during the transition period include: (i) low ozone concentration of the order of 5 ppbv around the equator, (ii) high concentrations of CO2, CH4 and N2O and (iii) variations in PM2.5 of 5–20μg/m3.

The hadronic properties of heavy–light flavour mesons, vis a vis B, B_s, D and D_s, are investigated by treating the light flavour relativistically and the heavy flavour non-relativistically with an effective quark–antiquark interaction potential of the form −α_c/r + Ar^ν. The Fermi momentum parameter generally used for experimental analysis, ground state masses, the ratio of the pseudoscalar decay constants and the vector–pseudoscalar mass differences and their ratios are computed for values of the potential index ν varying from 0.5 to 2.0. The excellent agreement of the properties calculated here with the experimental values suggest the most suitable potential form to be ν &equal; 0.5.

The ecological and economic problems associated with conventional cutting fluids can be resolved by identifying a sustainable and improved cooling/lubrication approach. The vegetable oil-based minimum quantity lubrication has a good amount of acceptability toward achieving sustainable and eco-friendly machining. This work investigates the efficacy of vegetable oil-based MQL (VMQL) and minimum quantity solid lubricant (MQSL) during turning AISI 4140 steel with coated carbide tools compared to dry and wet machining. Various sustainable aspects such as machining efficiency, total energy consumption, carbon emission, and various performance indicators such as surface roughness, chip–tool interface temperature, and tool life are evaluated under selected cooling/lubricating conditions. The experimental findings showcased the superiority of VMQL and MQSL in the form of improved machining performance compared to dry and wet machining. Noticeable reduction in surface roughness up to 27% and 20% at cutting speed 100 m/min and 45% and 41% at cutting speed 170 m/min is achieved with VMQL and MQSL, respectively. Furthermore, VMQL and MQSL reduced energy consumption by 33% and 28% at lower MRR and 26% and 22% at higher MRR, respectively, compared to dry machining. The results showcased the ability of VMQL in machining to achieve sustainability and energy-saving with improved product quality.

Prenatal treatment with a low dose of diazepam (1.25mg/kg/d, gestational day 14–20) has previously been found to cause longterm impairment of cellular immune responses in rat offspring. A possible site of action of diazepam, i.e., the peripheral-type (ω3) benzodiazepine receptor, was characterized on splenic macrophages as well as on a rat splenic cell preparation containing mainly lymphocytes. In membranes of both preparations, [3H]PK 11195 bound to a single site which in competition experiments exhibited characteristics of the (ω3) site. Prenatal exposure to diazepam was followed, at 8 weeks of life, by a marked decrease in maximal binding capacity (Bmax) of spleen macrophage membranes in offspring of both sexes, while membranes of the splenic cell preparation exhibited an increase of the dissociation constant of [3H]PK 11195 at 2 and 8 weeks of life. Both types of delayed effects may reduce the metabolic capacity of these immune cells, in which we have also observed deficits of cytokine release.

Amorphous V2O5.nH2O nanostructures (Ns) on CNTs coated/uncoated carbon fibre felt are very attractive electrodes for various electrochemical devices. In present article, we report the morphological and structural characterizations of electrodeposited V2O5.nH2O (denoted as δ-V2O5) phase on defective CNTs coated/uncoated graphitic carbon fibre felt using micro-Raman scattering, TGA curves, SEM and XPS techniques. Using electrochemical methodology, we obtained a highly stable superficial hydrated V2O5.nH2O (n ∼0.5) Ns on the surface of bare carbon fibre felt and defective CNT/carbon fibre felt composite. The intercalated hydroxide/H2O bonds are stable till 350°C temperature on both CNTs coated/uncoated felt substrates, which can be extracted from V2O5.nH2O structure using high laser power (≥10 mW). After de-hydration of V2O5.nH2O Ns, the local structural phase inclined to ε-V2O5. The surface morphological modification from flat to wrinkle like patterned of V2O5.nH2O Ns depends on electrodeposition parameters (current and time), while the CNT provokes the formation of a V2O5.nH2O layer on CNT/felt fibres with larger degree of roughness, hydration and thickness than in case of bare felt fibres. The proportion of oxidation-state (V+5∕+4∕+3) is barely influenced by CNT presence. Moreover, the electrodeposited V2O5.nH2O layer on graphite felt occurs heterogeneously on the carbon fibre electrode surface, unlike CNT/felt. On the other hand, the crystallite size (La) of micrometric felt and CNT/felt with and without V2O5.nH2O nanostructures are calculated, demonstrating that the adherence of V2O5.nH2O Ns is better on CNT coated felt than bare felt surface, which improved the crystalline properties of nanocarbons as well.