Study of the effect of different weave constructions on the drapeability of jute woven fabric

The growing global concern for environment on one hand and the alarming danger of carbon footprint generation along with non-biodegradability and higher toxicity generation from the use of synthetic fibres on the other have created a dire need to come back to natural fibres. During the application of fabrics at the sites for geotextile application and even in designing garments in the apparel sector, it has been observed that the ability of the fabric to assume a graceful appearance of the contour is very crucial in conveying the significance of drapeability of the natural fibre-made fabric. An attempt has been made in this work to evaluate the effect of different weave constructions on the drapeability of jute-woven fabrics to justify their application on the sites.     

Nitrate and fluoride contamination in groundwater of an intensively managed agroecosystem: A functional relationship

A study was conducted to assess the potential of nitrate-nitrogen (NO₃-N) and fluoride (F) contamination in drinking groundwater as a function of lithology, soil characteristics and agricultural activities in an intensively cultivated district in India. Two hundred and fifty two groundwater samples were collected at different depths from various types of wells and analyzed for pH, electrical conductivity (EC), NO₃-N load and F content. Database on lithology, soil properties, predominant cropping systems, fertilizer and pesticide uses were also recorded for the district. The NO₃-N load in groundwater samples were low ranging from 0.12 to 6.58 μg mL^− 1 with only 8.7% of them contained greater than 3.0 μg mL^− 1 well below the 10 μg mL^− 1, the threshold limit fixed by WHO for drinking purpose. Samples from the habitational areas showed higher NO₃-N content over the agricultural fields. The content decreased with increasing depth of wells (r = − 0.25, P ≤ 0.01) and increased with increasing rate of nitrogenous fertilizer application (r = 0.90, P ≤ 0.01) and was higher in areas where shallow- rather than deep-rooted crops (r = − 0.28, P = ≤ 0.01, with average root depth) are grown. The NO₃-N load also decreased with increasing bulk density (r = − 0.73, P ≤ 0.01) and clay content (r = − 0.51, P ≤ 0.01) but increased with increasing hydraulic conductivity (r = 0.68, P ≤ 0.01), organic C (r = 0.78, P ≤ 0.01) and potential plant available N (r = 0.82, P ≤ 0.01) of soils. Fluoride content in groundwater was also low (0.02 to 1.15 μg mL^− 1) with only 4.0% of them exceeding 1.0 μg mL^− 1 posing a potential threat of fluorosis. On average, its content varied little spatially and along depth of sampling aquifers indicating little occurrence of F containing rocks/minerals in the geology of the district. The content showed a significant positive correlation (r = 0.234, P = ≤ 0.01) with the amount of phosphatic fertilizer (single super phosphate) used for agriculture. Results thus indicated that the groundwater of the study area is presently safe for drinking purpose but some anthropogenic activities associated with intensive cultivation had a positive influence on its loading with NO₃-N and F.     

A Major Shell Protein of 1,2-Propanediol Utilization Microcompartment Conserves the Activity of Its Signature Enzyme at Higher Temperatures

A classic example of an all-protein natural nano-bioreactor, the bacterial microcompartment is a prokaryotic organelle that confines enzymes in a small volume enveloped by an outer protein shell. These protein compartments metabolize specific organic molecules, allowing bacteria to survive in restricted nutrient environments. In this work, 1,2-propanediol utilization microcompartment (PduMCP) was used as a model to study the effect of molecular confinement on the stability and catalytic activity of native enzymes in the microcompartment. A combination of enzyme assays, spectroscopic techniques, binding assays, and computational analysis were used to evaluate the impact of the major shell protein PduBB′ on the stability and activity of PduMCP′s signature enzyme, dioldehydratase PduCDE. While free PduCDE shows ∼45 % reduction in its optimum activity (activity at 37 °C) when exposed to a temperature of 45 °C, it retains similar activity up to 50 °C when encapsulated within PduMCP. PduBB′, a major component of the outer shell of PduMCP, preserves the catalytic efficiency of PduCDE under thermal stress and prevents temperature-induced unfolding and aggregation of PduCDE in vitro. We observed that while both PduB and PduB′ interact with the enzyme with micromolar affinity, only the PduBB′ combination influences its activity and stability, highlighting the importance of the unique PduBB′ combination in the functioning of PduMCP.     

Effect of material and process variability on the formability of aluminium alloys

Automotive parts are increasingly being manufactured to be lighter and stronger to minimise the environmental impact and to improve the crash performance of automobiles. The materials that are being used to achieve these aims tend to have lower formabilities compared to the traditionally used mild steel. This is particularly true for cold forming operations. As a consequence of the smaller forming window that is available, there is a greater need to understand the safety margins that are applied when manufacturing parts made from these materials. These safety margins are determined by estimations of the impact of material and process variabilities on formability as well as the attitude that is adopted towards risk. This study looked at the impact of material and process variabilities on the cold formability of two aluminium grades: AA6111-T4 and AA5754-O. The forming factors studied included changes to overall material properties, tool surface roughness, quantity of lubricant, tooling temperature and gauge. Because of the complexity of the forming process, the problem was reduced to a study of formability under plane strain stretch conditions. Particular emphasis was placed in quantifying the temperature of tooling during cold forming and understanding its effect on formability. It was found that the safety factor applied to AA5754-O can be lower than that used for AA6111-T4.     

Energy transfer and morphology study of a new iridium based cyclometalated phosphorescent complex

This paper reports synthesis and characterization of a new phosphorescent iridium complex namely iridium (III) bis (2-phenylpyridinato–N, C^2′) picolinate [(ppy)₂Irpic]. For its future use in organic light emitting diodes (OLED), we doped the iridium complex into various host materials and carried out a study of energy transfer process through photoluminescence (PL) and photoluminescence excitation (PLE) measurements onto the blended films with different concentrations of (ppy)₂Irpic. The blended films were casted by the spin coating method, as to make the device fabrication process cheaper. The selected host materials were poly(N-vinylcarbazole) (PVK), poly(9,9-dihexylfluorene) (PDHF) and N,N′-diphenyl-bis(3-methylphenyl) [1,1′-biphenyl]-4,4′-diamine (TPD). The blended films with TPD as a host were made in poly(methyl-methacrylate) (PMMA) matrix. The emission from the host molecule disappears at a particular concentration of (ppy)₂Irpic, which is determined as 5 wt%, 12 wt% and 20 wt% of the host materials for blended PVK, TPD (20% by weight of PMMA) and TPD (10% by weight of PMMA) films, respectively. No energy transfer could be observed for PDHF for the concentration range of 0.1–20 wt%. The energy transfer efficiency and the morphology of the various blends were also studied in order to find out the most appropriate host material for the device applications.     

Effects of tuned mass damper on correlation of wind‐induced responses and combination coefficients of equivalent static wind loads of high‐rise buildings

Tuned mass dampers (TMDs) are employed to control the wind‐induced responses of tall buildings. In the meantime, TMD may have an impact on the correlation of wind‐induced responses and combination coefficients of equivalent static wind loads (ESWLs). First, the mass matrix and stiffness matrix were extracted in this paper in accordance with the structural analysis model of two high‐rise buildings, and on that basis, the wind‐induced vibration responses analysis model with and without TMD was established. Second, the synchronous multipoint wind tunnel test to measure the pressure was performed for two high‐rise buildings, and the time history of wind‐induced vibration responses with and without TMD was studied. Finally, the impact of TMD on the correlation of wind‐induced responses and combination coefficients of ESWLs was discussed. The results of two examples suggest that after the installation of TMD, the increase of ρ_xy was 2.1% to 35.0% and ρ_yz was 2.8% to 45.6% at all wind directions for Building 1, and the increase of ρ_xy was 3.9% to 17.1% and ρ_yz was 6.8% to 38.3% for Building 2. The combination coefficients of ESWLs of two buildings were 3% to 6% larger than that of the original structure. The conclusion of this paper can be referenced by the wind resistant design of high‐rise buildings with TMD.     

Rehabilitating acid soils for increasing crop productivity through low-cost liming material

Productivity of red and lateritic soils is low because of their acidity and deficiencies in few essential nutrients viz., nitrogen, phosphorus, calcium, zinc, boron, molybdenum etc. We compared the effectiveness of basic slag, a low-cost liming material, with that of calcite as an ameliorant for these soils using mustard followed by rice as test crops. Experiments were conducted with three levels of each of basic slag and calcite along with a control on farmers' fields at 14 different locations. Influence of farmyard manure (FYM) and poultry manure (PM) on the effectiveness of the slag was also tested. On an average, basic slag performed better than calcite in increasing yields of both mustard and rice and left over higher amounts of available Ca, Si and Zn in residual soils. The slag also improved N, P, K and Ca nutrition of mustard and Si and Zn nutrition of rice with a favorable benefit:cost (B:C) ratio over the calcite (4.82 vs. 1.44). Effectiveness of the basic slag improved when it was applied in combination with FYM or PM (B:C, 5.83 and 6.27). Basic slag can, therefore, be advocated for use in the acidic red and lateritic soils for economically improving their productivity.     

Investigation of thermally induced bistable behaviour for tow-steered laminates

Traditionally, bistable laminates have been developed from prepreg plies stacked up together to achieve a layup which is either constant or discretely varying over the planform of the laminate. Laminates with discrete variation in layup are, in particular, of interest as they offer the prospect of easier blending. Moreover, such laminates can be manufactured to have Variable Angle Tows (VATs) in a ply using a tow-steering technique, doing so, ensures fibre-continuity and may impart additional structural strength. This paper presents an approach to develop finite element (FE) models which can accurately predict the cured shape(s) of tow-steered laminates that are designed to be bistable. Manufactured laminates are characterised using microscopy and resin burn-off tests to identify resin-rich layers, ply-thicknesses and fibre volume fractions (V_f) – which are then translated into FE models. Presented data highlights the influence of the manufacturing process in the thermally induced bistable behaviour of tow-steered laminates.