The effectiveness of combining rolling deformation with wire-arc additive manufacture on β-Grain refinement and texture modification in Ti-6Al-4V

In Additive Manufacture (AM), with the widely used titanium alloy Ti–6Al–4V, the solidification conditions typically result in undesirable, coarse-columnar, primary β grain structures. This can result in a strong texture and mechanical anisotropy in AM components. Here, we have investigated the efficacy of a new approach to promote β grain refinement in Wire–Arc Additive Manufacture (WAAM) of large scale parts, which combines a rolling step sequentially with layer deposition. It has been found that when applied in-process, to each added layer, only a surprisingly low level of deformation is required to greatly reduce the β grain size. From EBSD analysis of the rolling strain distribution in each layer and reconstruction of the prior β grain structure, it has been demonstrated that the normally coarse centimetre scale columnar β grain structure could be refined down to < 100 μm. Moreover, in the process both the β and α phase textures were substantially weakened to close to random. It is postulated that the deformation step causes new β orientations to develop, through local heterogeneities in the deformation structure, which act as nuclei during the α → β transformation that occurs as each layer is re-heated by the subsequent deposition pass

Air pollution modelling to predict maximum ground level concentration for dust from a palm oil mill stack

The study is to model emission from a stack to estimate ground level concentration from a palm oil mill. The case study is a mill located in Kuala Langat, Selangor. Emission source is from boilers stacks. The exercise determines the estimate the ground level concentrations for dust to the surrounding areas through the utilization of modelling software. The surround area is relatively flat, an industrial area surrounded by factories and with palm oil plantations in the outskirts. The model utilized in the study was to gauge the worst-case scenario. Ambient air concentrations were garnered calculate the increase to localized conditions

Big Data Analytics and Auditing: A Review and Synthesis of Literature

The use of data analytics in auditing is increasingly growing. The application of common data analytics to audit engagements appears to be lagging behind other areas of practice, even though data analytics is thought to represent the future of audit, and there are still few publications that have examined this influence. This article reviews data analytics in audits and its potential for future audit engagements to describe the evolution of this research trend and picture its future growth directions. Future audit research potential and difficulties are also discussed. Data analytics application in auditing has enormous potential for refining audit quality, decreasing errors, increasing process transparency, and enhancing stakeholders’ confidence. We conducted a systematic literature review using the PRISMA approach. A total of 100 articles published in English from January 2011 to November 2021 were identified through a systematic search of reputed databases, including Web of Science and Scopus and many others. Our analysis reveals that data analytics is a promising domain for the auditing practice as it improves audit efficiency and promotes audit work digital transformation. While reviewing the most pertinent literature in the context of data analytics in auditing, this study offers insights on potential new directions and waning views on big data analytics in auditing. Doi: 10.28991/ESJ-2023-07-02-023 Full Text: PD

3-Acetyl-4-hydroxy­phenyl acrylate

In the title compound, C12H12O4, the hydr­oxy O and the C and O atoms of the acetyl group are almost coplanar [maximum deviation = 0.0356 (1) Å] with the benzene ring. The dihedral angle between the benzene ring and the plane through the non-H atoms of the methacrylo­yloxy group is 86.1 (1)°. In the crystal structure, mol­ecules are linked by two C—H⋯O hydrogen bonds, forming dimers with graph-set descriptor R 2 2(16). A strong intra­molecular O—H⋯O hydrogen bond is also observed

Non-invasive management of peripheral arterial disease.

BACKGROUND: Peripheral arterial disease (PAD) is common and symptoms can be debilitating and lethal. Risk management, exercise, radiological and surgical intervention are all valuable therapies, but morbidity and mortality rates from this disease are increasing. Circulatory enhancement can be achieved using simple medical electronic devices, with claims of minimal adverse side effects. The evidence for these is variable, prompting a review of the available literature. METHODS: Embase and Medline were interrogated for full text articles in humans and written in English. Any external medical devices used in the management of peripheral arterial disease were included if they had objective outcome data. RESULTS: Thirty-one papers met inclusion criteria, but protocols were heterogenous. The medical devices reported were intermittent pneumatic compression (IPC), electronic nerve (NMES) or muscle stimulators (EMS), and galvanic electrical dressings. In patients with intermittent claudication, IPC devices increase popliteal artery velocity (49-70 %) and flow (49-84 %). Gastrocnemius EMS increased superficial femoral artery flow by 140 %. Over 4.5-6 months IPC increased intermittent claudication distance (ICD) (97-150 %) and absolute walking distance (AWD) (84-112 %), with an associated increase in quality of life. NMES of the calf increased ICD and AWD by 82 % and 61-150 % at 4 weeks, and 26 % and 34 % at 8 weeks. In patients with critical limb ischaemia IPC reduced rest pain in 40-100 % and was associated with ulcer healing rates of 26 %. IPC had an early limb salvage rate of 58-83 % at 1-3 months, and 58-94 % at 1.5-3.5 years. No studies have reported the use of EMS or NMES in the management of CLI. CONCLUSION: There is evidence to support the use of IPC in the management of claudication and CLI. There is a building body of literature to support the use of electrical stimulators in PAD, but this is low level to date. Devices may be of special benefit to those with limited exercise capacity, and in non-reconstructable critical limb ischaemia. Galvanic stimulation is not recommended

Children’s rights online: challenges, dilemmas and emerging directions

In debates over internet governance, the interests of children figure unevenly, and only partial progress has been made in supporting children’s rights online globally. This chapter examines how the UN Convention on the Rights of the Child is helpful in mapping children’s rights to provision, protection and participation as they apply online as well as offline. However, challenges remain. First, opportunities and risks are positively linked, policy approaches are needed to resolve the potential conflict between protection on the one hand, and provision and participation on the other. Second, while parents may be relied on to some degree to balance their child’s rights and needs, the evidence suggests that a minority of parents are ill-equipped to manage this. Third, resolution is needed regarding the responsibility for implementing digital rights, since many governments prefer self-regulation in relation to internet governance. The chapter concludes by calling for a global governance body charged with ensuring the delivery of children’s rights

Facile Synthetic Route for Well-Defined Poly(3-hexylthiophene)-block-poly(methyl methacrylate) Copolymer by Anionic Coupling Reaction

We have demonstrated a facile synthetic route for well-defined poly(3-hexylthiophene)-block-poly(methyl methacrylate) copolymer (P3HT-b-PMMA) by anionic coupling reaction. For successful coupling reaction, newly generated anions should be more stable (less reactive) than initial anions of reactants. In this study, we chose a-phenyl acrylate (PA)-capped P3HTs for successful coupling with living PMMA anions because the anions at PA group are more stable than living PMMA anions. We found that all of the PA groups located at the end of P3HT were completely coupled with living PMMA anions having slightly excess amount (1.5 equiv relative PA-capped P3HT). The unreactive PMMA homopolymers in crude product were completely removed by using column chromatography, resulting in narrow molecular weight distribution of pure P3HT-b-PMMA. The optical property and thin film morphology of the P3HT-b-PMMA were investigated by using UV-vis spectra and atomic force microscopy, respectively.X114239sciescopu

Facile Synthesis of Well-Defined Coil-Rod-Coil Block Copolymer Composed of Regioregular Poly(3-hexylthiophene) via Anionic Coupling Reaction

We introduced a facile synthetic strategy of coil-rod-coil triblock copolymers containing regioregular poly(3-hexylthiophene) (P3HT) block via anionic coupling reaction. Two different coil blocks (poly(2-vinylpyridine) (P2VP) and polyisoprene (PI)) were selected. P2VP-b-P3HT-b-P2VP copolymer was synthesized in a polar solvent of tetrahydrofuran, whereas PI-b-P3HT-b-PI copolymer was synthesized in a nonpolar solvent of benzene. For the synthesis of both block copolymers, the chain ends of the P3HT were capped by the aldehyde group. Because of the higher electrophilicity of the carbon in the aldehyde group compared with that in allyl (or vinyl) group, the coupling reaction between living anions in the coil blocks and aldehyde-capped P3HT was carried out more effectively. When the excess amount of the living P2VP (or PI) anions was used, all of aldehyde-capped P3HT were completely reacted with P2VP (or PI) anions without leaving any P3HT homopolymer in the product. When the unreacted P2VP (or PI) was removed by column chromatography, two synthesized triblock copolymers had narrow molecular weight distributions.X114946sciescopu