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Titanium alloy is difficult to machining in the conventional machining process. Hybrid production technology for abrasive water jet machining (AWJM) allows the machining of all engineering applications. This paper explores the optimization of the process variables of Titanium alloy AWJM (Ti- 6Al- 2Sn- 4Zr- 2Mo). The AWJM process parameters such as water jet strength, traverse speed, and standoff distance were studied against the material removal rate, surface roughness, kerf angle. The contribution of this parameter to responses has been calculated by variance analysis. For material removal rate, surface roughness, kerf angle, regression models were obtained.

The primary goal of this research is to analyze a new polymer-based composite material with various reinforcement angle orientations and to investigate its flexural behavior. E-2 glass fiber reinforcement and epoxy resin for matrix are used in fibre reinforced polymer matrix composites. Three sets of rectangular specimens are prepared according to ASTM standards (D7264). First set comprises of 30° angle-oriented specimen, second and third set comprises of 45° and 90° respectively. These specimens are subjected to flexural test in UTM and load being applied gradually until the material fails. It is evident from the results that the load bearing capacity of 90° orientation laminate is more when compared to 30° and 45°.These experimental results are compared with FEA results and found to have a good correlation.

The main objective of this work is to develop a new polymer based composite material having different reinforcement angle orientations and studies its tensile behavior. For fiber reinforced polymer matrix composites E-2 glass fiber reinforcement and epoxy resin for matrix is used. E-2 g1ass fiber has high strength, chemical resistance and good insulating properties. Epoxy being less viscous allows good adhesion to fibers used in laminate preparation, without misalignment of fibers. Hand layup technique has been adopted for preparation of laminate. Glass fibers are laid, mixture of epoxy resin and hardener is smeared on it alternately, until laminate of desired thickness is achieved, and is left to atmosphere for curing. 2.5 mm laminate is prepared by placing glass fibers of 0.25 mm thickness one above the other. The prepared laminate is then taken for cutting according to ASTM standards (D3039) of 3 sets of rectangular specimens. For first set comprises of 90° angle-oriented specimen, second and third sets for 45° and 30° respectively. These specimens are subjected to tensile test in Lloyd UTM and load being applied gradually at the rate of 2 mm/min is continued until the material fails. The computer simulation plots the graph during the entire testing process and stops when the material fails.

The main challenge of integrating high photovoltaic (PV) systems in power grids is managing their associated uncertainty which poses significant risks on the system stability and reliability. A probabilistic approach is well-suited to explore and analyse the impact of these intermittencies and uncertainties on power system operation. This paper proposes a probabilistic risk-based assessment (PRBA) framework which is suitable for power systems with high penetration of renewables such as PVs. Conventional analytical security assessment approaches typically examine the behaviour of electromechanical modes under varying operation scenarios in the power grid and often focus only on a few specific modes of interest. However, this may impose a small-disturbance stability risk of missing out critical information from other unobserved modes. The methodology proposed in this paper aims to capture the behaviours of all critical modes through modal analysis and risk matrices in order to quantify the stability risks associated with high PV-integrated power networks. Feasibility of the proposed framework is tested on a modified version of the 39-bus New England test network. Probabilistic risk-based assessment is performed and the severities measured are assessed using a sensitivity matrix to evaluate the overall small-signal instability risks associated with various PV penetration levels.

Hydroxyapatite ((Ca10(PO4)6(OH)2, HAp) based chromatography matrix has attracted great interest in the field of protein separation. However, researchers have been trying to combat the growing costs associated with the HAp matrix. In the present investigation, we utilized a cheap biological waste material, viz. eggshells, for the development of hydroxyapatite (HAp) resins and evaluated them for protein purification. Initially, the calcite of the eggshell carbonate was converted into metastable vaterite microspheres. The HAp microspheres (ECHAp) were then prepared from eggshell carbonate microspheres using a novel dissolution-precipitation process. Synthetic source calcium carbonate was also used to prepare HAp microspheres (CHAp) for comparison. The purity and morphology of the apatite microspheres were characterized using X-ray diffraction (XRD) method, Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and laser diffraction particle analysis. Although both the apatites have similar morphology, the ECHAp has a larger surface area of 33.8 m2 g−1 compared to CHAp of 17.27 m2 g−1 by surface area analysis method. A commercial HAp matrix (CHT) with similar properties was also studied for comparison. All the apatite microspheres were found to have a similar protein binding capacity for bovine serum albumin (BSA). But ECHAp showed better protein separation for BSA and lysozyme mixture compared to CHAp and CHT matrices. The ECHAp matrix was also found to be highly stable over 20 purification cycles. Hence, the eggshell waste seems to have the potential for HAp matrix by a novel carbonate route with ease of preparation and also an economical packing material for chromatographic purification of biomolecules.

Background Rheumatic heart disease (RHD) affects more than 33,000,000 individuals, mostly from low- and middle-income countries. The Cape Town Declaration On Access to Cardiac Surgery in the Developing World was published in August 2018, signaling the commitment of the global cardiac surgery and cardiology communities to improving care for RHD patients. Methods As the Cape Town Declaration formed the basis for which the Cardiac Surgery Intersociety Alliance (CSIA) was formed, the purpose of this article is to describe the history of the CSIA, its formation, ongoing activities, and future directions, including the announcement of selected pilot sites. Results The CSIA is an international alliance consisting of representatives from major cardiothoracic surgical societies and the World Heart Federation. Activities have included meetings at annual conferences, exhibit hall participation for advertisement and recruitment, and publication of selection criteria for cardiac surgery centers to apply for CSIA support. Criteria focused on local operating capacity, local championing, governmental and facility support, appropriate identification of a specific gap in care, and desire to engage in future research. Eleven applications were received for which three finalist sites were selected and site visits conducted. The two selected sites were Hospital Central Maputo (Mozambique) and King Faisal Hospital Kigali (Rwanda). Conclusions Substantial progress has been made since the passing of the Cape Town Declaration and the formation of the CSIA, but ongoing efforts with collaboration of all committed parties—cardiac surgery, cardiology, industry, and government—will be necessary to improve access to life-saving cardiac surgery for RHD patients.