A ferroelectric memristor

Memristors are continuously tunable resistors that emulate synapses. Conceptualized in the 1970s, they traditionally operate by voltage-induced displacements of matter, but the mechanism remains controversial. Purely electronic memristors have recently emerged based on well-established physical phenomena with albeit modest resistance changes. Here we demonstrate that voltage-controlled domain configurations in ferroelectric tunnel barriers yield memristive behaviour with resistance variations exceeding two orders of magnitude and a 10 ns operation speed. Using models of ferroelectric-domain nucleation and growth we explain the quasi-continuous resistance variations and derive a simple analytical expression for the memristive effect. Our results suggest new opportunities for ferroelectrics as the hardware basis of future neuromorphic computational architectures

Social Media, Gender and the Mediatisation of War: Exploring the German Armed Forces’ Visual Representation of the Afghanistan Operation on Facebook

Studies on the mediatisation of war point to attempts of governments to regulate the visual perspective of their involvements in armed conflict – the most notable example being the practice of ‘embedded reporting’ in Iraq and Afghanistan. This paper focuses on a different strategy of visual meaning-making, namely, the publication of images on social media by armed forces themselves. Specifically, we argue that the mediatisation of war literature could profit from an increased engagement with feminist research, both within Critical Security/Critical Military Studies and within Science and Technology Studies that highlight the close connection between masculinity, technology and control. The article examines the German military mission in Afghanistan as represented on the German armed forces’ official Facebook page. Germany constitutes an interesting, and largely neglected, case for the growing literature on the mediatisation of war: its strong antimilitarist political culture makes the representation of war particularly delicate. The paper examines specific representational patterns of Germany’s involvement in Afghanistan and discusses the implications which arise from what is placed inside the frame of visibility and what remains out of its view

PRODUCTION AND CHARACTERIZATION OF BIOFUEL PRODUCTION FROM EGUSI (CITRULLUS LANATUS) VEGETABLE OIL

Green house effect and ozone layer depletion due continuous environmental pollution from fossil fuel has speed up the quest for search of alternative energy fuel. In recent year, biofouls has attracted much attention as a reliable substitute to fossil fuel. The objective of this study was to evaluate and characterize biofuel produced from Egusi vegetable oil by applying standard method of transesterification. This study was carried out at Processing and Storage Engineering Departmental (PSED) laboratory of National Centre for Agricultural Mechanization (NCAM), Ilorin Kwara State, Nigeria. The results of the proximate characterization of the produced Egusi vegetable oil shows crude protein, crude fibre, ether extract, moisture content, ash content and carbohydrate composition of 20.6%, 13.3%, 50.6%, 4.3%, 3.0% and 8.2% respectively. The transesterification of Egusi vegetable oil in this study yielded 63.7% of methyl ester. The characterization results of  the biofuel produced shows kinematic viscosity, density, cloud point, flash point, pour point, fire point, acid value, iodine value, Saponification and specific gravity values of 4.6, 0.714, 5, 210, -3, 250, 0.54, 0.69, 0.26 and 0.915 respectively. The results were compared with the American Society for Testing Materials (ASTM 6751) for standard. Information from this study will expand the scope of knowledge on the search for an alternative fuel to fossil fuel. Also, this will serve as a guide in both policy and management of global warming