Vortex fluidic mediated synthesis of TiO2 nanoparticle/MXene composites

Oxidation of MXene in a vortex fluidic device (VFD) operating under continuous flow results in exfoliation and fragmentation into nanoparticles of surface oxidised 2D material with further oxidation of the nanoparticles into anatase (TiO 2 ). These MXene and anatase nanoparticles co‐assemble into stable micron sized spheres which are topologically smooth, decorating the surface of exfoliated MXene. The formation of this composite material in the dynamic thin film in the VFD was optimised by systematically exploring the operating parameters of the microfluidic platform, determined at 45 o tilt angle for the 20 mm diamater glass tube spinning at 5k rpm, with a flow rate of a colloidal dispersion of MXene in aqueous H 2 O 2 (30%) at 0.75 mL/min, concentration of MXene 0.5 mg/mL

Continuous flow vortex fluidic-mediated exfoliation and fragmentation of two-dimensional MXene

MXene (Ti2CTx) is exfoliated in a vortex fluidic device (VFD), as a thin film microfluidic platform, under continuous flow conditions, down to ca 3 nm thin multi-layered twodimensional (2D) material, as determined using AFM. The optimized process, under an inert atmosphere of nitrogen to avoid oxidation of the material, was established by systematically exploring the operating parameters of the VFD, along with the concentration of the dispersed starting material and the choice of solvent, which was a 1 : 1 mixture of isopropyl alcohol and water. There is also some fragmentation of the 2D material into nanoparticles ca 68 nm in diameter

Boundary element formulations for the numerical solution of two-dimensional diffusion problems with variable coefficients

This is the post-print version of the final paper published in Computers & Mathematics with Applications. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2012 Elsevier B.V.This paper presents new formulations of the radial integration boundary integral equation (RIBIE) and the radial integration boundary integro-differential equation (RIBIDE) methods for the numerical solution of two-dimensional diffusion problems with variable coefficients. The methods use either a specially constructed parametrix (Levi function) or the standard fundamental solution for the Laplace equation to reduce the boundary-value problem (BVP) to a boundary–domain integral equation (BDIE) or boundary–domain integro-differential equation (BDIDE). The radial integration method (RIM) is then employed to convert the domain integrals arising in both BDIE and BDIDE methods into equivalent boundary integrals. The resulting formulations lead to pure boundary integral and integro-differential equations with no domain integrals. Furthermore, a subdomain decomposition technique (SDBDIE) is proposed, which leads to a sparse system of linear equations, thus avoiding the need to calculate a large number of domain integrals. Numerical examples are presented for several simple problems, for which exact solutions are available, to demonstrate the efficiency of the proposed approaches

Carbon Sequestration in Biogenic Magnesite and Other Magnesium Carbonate Minerals

The stability and longevity of carbonate minerals make them an ideal sink for surplus atmospheric carbon dioxide. Biogenic magnesium carbonate mineral precipitation from the magnesium-rich tailings generated by many mining operations could offset net mining greenhouse gas emissions, while simultaneously giving value to mine waste products. In this investigation, cyanobacteria in a wetland bioreactor enabled the precipitation of magnesite (MgCO3), hydromagnesite [Mg5(CO3)4(OH)2·4H2O], and dypingite [Mg5(CO3)4(OH)2·5H2O] from a synthetic wastewater comparable in chemistry to what is produced by acid leaching of ultramafic mine tailings. These precipitates occurred as micrometer-scale mineral grains and microcrystalline carbonate coatings that entombed filamentous cyanobacteria. This provides the first laboratory demonstration of low temperature, biogenic magnesite precipitation for carbon sequestration purposes. These findings demonstrate the importance of extracellular polymeric substances in microbially enabled carbonate mineral nucleation. Fluid composition was monitored to determine carbon sequestration rates. The results demonstrate that up to 238 t of CO2 could be stored per hectare of wetland/year if this method of carbon dioxide sequestration was implemented at an ultramafic mine tailing storage facility. The abundance of tailings available for carbonation and the anticipated global implementation of carbon pricing make this method of mineral carbonation worth further investigation

The Red Sea under the Caliphal Dynasties, c. 639–1171

Students of world history will be familiar with the Red Sea as a strategic communications corridor linking the Mediterranean to the Indian Ocean. This paper examines the Red Sea region between the seventh and twelfth centuries, when it was ruled by a succession of Islamic caliphal dynasties, namely, the Umayyads, ʿAbbāsids, and Fāṭimids. It first sets out a sketch of the political history of the Red Sea and its constituent hinterland polities, including particularly Egypt, Sudan, al‐Ḥijāz, and Yemen, drawing attention to episodes and processes in which the Red Sea was significant. A section on Africa and Arabia explores the Red Sea as a zone of economic and social interaction; another section deals with the historic shift of Indian Ocean trade from the ʿAbbāsid Persian Gulf to the Fāṭimid Red Sea. Finally, the impact of the Red Sea on its constituent hinterland polities and the wider sweep of Islamic history is considered

Al Ain Oases Mapping Project: Qattārah Oasis, past and present (poster)

The Al Ain Oases Mapping Project is a collaboration between the Abu Dhabi Tourism and Culture Authority and Zayed University. It aims to document the present oasis landscape and identify surviving historic components, while at the same time engaging Emirati students with their heritage and building capacity for archaeology in the UAE. The project utilizes a non-intrusive field-walking methodology suitable for a class of undergraduate students. It further draws on the students\u27 community links and bilingualism to contact former residents of the oasis villages and undertake oral history interviews. The first season\u27s work focused on Qattārah Oasis and contributes to the established programme of works there; future seasons will expand the survey to neighbouring Jīmī Oasis and the other oases of al-\u27Ayn. The results will inform continued archaeological exploration of the oases by TCA

Supporting ultra poor people with rehabilitation and therapy among families of children with cerebral palsy in rural Bangladesh (SUPPORT CP) : Protocol of a randomised controlled trial

Introduction Poverty is a key contributor to delayed diagnosis and limited access to early intervention and rehabilitation for children with cerebral palsy (CP) in rural Bangladesh. 97% of families of children with CP live below the poverty line in Bangladesh. Therefore, in low-and middle-income countries (LMICs), efforts to improve outcomes for children with CP (including health-related quality of life, motor function, communication, and nutritional attainments) should also include measures to improve family economic and social capital. We propose a randomised controlled trial (RCT) to evaluate the effectiveness of an integrated microfinance/livelihood and community-based rehabilitation (IMCBR) program for ultra-poor families of children with CP in rural Bangladesh. Material and methods This will be a cluster RCT comparing three arms: (a) integrated microfinance/livelihood and community-based rehabilitation (IMCBR); (b) community-based rehabilitation (CBR) alone; and (c) care-as-usual (i.e. no intervention). Seven clusters will be recruited within each arm. Each cluster will consist of 10 child-caregiver dyads totalling 21 clusters with 210 dyads. Parents recruited in the IMCBR arm will take part in a microfinance/livelihood program and Parent Training Module (PTM), their children with CP will take part in a Goal Directed Training (GDT) program. The programs will be facilitated by specially trained Community Rehabilitation Officers. The CBR arm includes the same PTM and GDT interventions excluding the microfinance/livelihood program. The care-as-usual arm will be provided with information about early intervention and rehabilitation. The assessors will be blinded to group allocation. The duration of the intervention will be 12 months; outcomes will be measured at baseline, 6 months, 12 months, and 18 months. Conclusion This will be the first RCT of an integrated microfinance/livelihood and CBR program for children with CP in LMIC settings. Evidence from the study could transform approaches to improving wellbeing of children with CP and their ultra-poor families

Taking advantage of Ramadan and January in Muslim countries

Studies have shown that religious beliefs and practice play an important role in influencing share price behaviour. Evidence of a Ramadan effect has been documented in Muslim countries suggesting an increase in mean returns as well as a reduction in volatility during the ninth month of the Islamic calendar. In addition to the Ramadan effect, studies have also documented a January effect in Muslim countries. The current study investigates what happens when the Ramadan effect and the January effect occur at the same time. Controlling for the effects of financial crises and time-varying volatility in returns, the results for individual company data from four countries with sizeable Muslim populations indicate higher returns and lower volatility when these two effects overlap, except in one, arguably more Western country, Turkey