Effect of Metallic Inserts on the Strength of Pin Joints Prepared from Glass Fiber Reinforced Composites

The present study deals with the failure analysis of pin joints by varying different geometric parameters i.e., edge distance to hole diameter (E/D) ratio and width to hole diameter (W/D) ratio. Pin joints were prepared from the glass fiber reinforced laminates incorporating the metal inserts. A range of 2 to 5 and 3 to 6 was considered for E/D and W/D ratios, respectively. The stress around the hole was redistributed by incorporating the metal inserts in the hole to increase the load carrying capacity. To predict the failure loads and failure modes numerically, progressive damage analysis along with Hashin failure criteria was used in the pin joints. Strength of the pin joints increased in the range of 65 per cent to 92 per cent with metal insert due to the redistribution of the stresses around the hole. Progressive damage analysis gave a good correlation with experimental findings. Thereafter, the strength of the joint was predicted by varying the thickness of the metal inserts

Effect of Ply Orientation on Strength and Failure Mode of Pin Jointed Unidirectional Glass-epoxy Nanoclay Laminates

In the present work the effect of the different ply orientations and nano filler on the bearing strength and failure mode of the pin joints is investigated both experimentally and numerically. Glass-epoxy composite laminates were prepared with [0°/45°/90°], [0°/45°/0°] and [0°/90°/0°] ply orientations. Nanoclay filler with 1, 2, 3, 4 and 5wt% were added in the epoxy for the said orientations to prepare the pin joints. Results show that the strength of the pin joints is drastically dependent on both ply orientations and nanofiller wt%. The joint geometry i.e., the distance from the free edge of specimen to the diameter of the hole (E/D) ratio and width of the specimen to the diameter of the holes (W/D) ratio were also investigated which effected the failure mode of the joints. Tsai-Wu failure theory along with the characteristics curve method was used for the prediction of failure modes numerically

Electrochemical stimuli-driven facile metal-free hydrogen evolution from pyrene-porphyrin-based crystalline covalent organic framework

A [2+2] Schiff base type condensation between 5, 10,15, 20 tetrakis(4 aminophenyl)porphyrin (TAP) and 1,3,6,8 tetrakis (4 formylphenyl) pyrene (TFFPy) under solvothermal condition yields a crystalline, quasi two dimensional covalent organic framework (SB PORPy COF). The porphyrin and pyrene units are alternatively occupied in the vertex of 3D triclinic crystal having permanent micro-porosity with moderately high surface area (~869 m2g-1) and promising chemical stability. The AA stacking of the monolayers give a pyrene bridged conducting channel. SB PORPy COF has been exploited for metal free hydrogen production to understand the electrochemical behavior using the imine based docking site in acidic media. SB PORPy-COF has shown the onset potential of 50 mV and the Tafel slope of 116 mV dec-1. We expect that the addendum of the imine based COF would not only enrich the structural variety but also help to understand the electrochemical behavior of these class of materials

Effect of irrigation and nitrogen on water use, moisture extraction pattern, nitrogen uptake and yield of coriander (Coriandrum sativum L.) in north-western irrigated plains of Rajasthan

An experiment was conducted at Sriganganagar (Rajasthan) to study water use, water useefficiency, nitrogen uptake, yield and economics of coriander (Coriandrum sativum) cultivars(RCr 41, RCr 435) under various levels of nitrogen (20, 40 and 60 kg ha-1) and irrigation (IW/CPE ratios 0.6, 0.8 and irrigation at branching + flowering + seed formation stages). Thehighest seed yield (10.98 q ha-1), yield attributes and benefit: cost ratio (2.65) were recordedwith 60 kg nitrogen ha-1. Increasing levels of nitrogen also recorded higher consumptive useof water and nitrogen uptake. Plants under higher levels of nitrogen (60 kg ha-1) extractedmore water from the lower depth (60-90 cm) than lower level of nitrogen (20 kg ha-1). Increasein irrigation frequency significantly enhanced the yield and yield attributes of both thecultivars. Similarly, water use, nitrogen uptake and benefit:cost ratio were also higher withhigher levels of irrigation. &nbsp

Response of fenugreek (Trigonella foenum-graecum) to bio-regulators TGA and N-acetyl cystein under drip irrigation levels

Field experiments were conducted during winter seasons of 2010–11 and 2011–12 at Bikaner (Rajasthan) to study the effect of bioregulators viz., TGA and N-acetyl cystein under different drip irrigation levels on yield, yield attributes, water use and water use efficiency of fenugreek. The highest plant height (69 cm) and yield attributes viz., branches plant-1 (7.6), pods plant-1 (46.3), pod length (13.5 cm), seed pod-1 (16) and test weight (12.7 g) were recorded with 100% ETc + TGA (200 ppm). Further, 80% ETc + TGA (200 ppm), and 100% ETc + N-acetyl cystein (both 10 and 20 ppm) and 100% ETc + TGA (both 100 and 200 ppm) produced comparable plant height. However, 80% ETc + N-acetyl cystein (both 10 and 20 ppm), 80% ETc + TGA (both 100 and 200 ppm), 100% ETc + N-acetyl cystein (both 10 and 20 ppm), 100% ETc + TGA (100 ppm) and 100% ETc + TGA (200 ppm) recorded at par branches plant-1, pods plant-1, pod length and test weight of fenugreek. Highest seed and biological yield of fenugreek were recorded with 100% ETc + Nacetyl cystein (20 ppm), which was at par with 100% ETc + N-acetyl cystein (10 ppm) and 100% ETc + TGA (both 100 and 200 ppm). Maximum water use recorded at 100% ETc with or without bioregulators, whereas maximum water use efficiency was recorded with 60% ETc + N-acetyl cystein (20 ppm) followed by 60% ETc + N-acetyl cystein (10 ppm). &nbsp