King Abdullah University of Science and Technology

About: King Abdullah University of Science and Technology is a education organization based out in Jeddah, Saudi Arabia. It is known for research contribution in the topics: Catalysis & Membrane. The organization has 6221 authors who have published 22019 publications receiving 625706 citations. The organization is also known as: KAUST.

Tunable Topological Phononic Crystals

Abstract: Topological insulators are of practical interest for the one-way wave propagation afforded by their edge states, and are not limited to electronic systems. In many cases the topological transition occurs when time-reversal symmetry is broken and is not tunable, but here the authors design a phononic crystal with a transition that $c\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}n$ be tuned by varying the structure's geometric size, or the external airflow (velocity field). Their results are universal and should expand our ability to tailor sound waves, as in acoustic diodes.

Reticular Synthesis of HKUST-like tbo-MOFs with Enhanced CH4 Storage

Abstract: Successful implementation of reticular chemistry using a judiciously designed rigid octatopic carboxylate organic linker allowed the construction of expanded HKUST-1-like tbo-MOF series with intrinsic strong CH4 adsorption sites. The Cu-analogue displayed a concomitant enhancement of the gravimetric and volumetric surface area with the highest reported CH4 uptake among the tbo family, comparable to the best performing metal organic frameworks (MOFs) for CH4 storage. The corresponding gravimetric (BET) and volumetric surface areas of 3971 m(2) g(-1) and 2363 m(2) cm(-3) represent an increase of 115% and 47%, respectively, in comparison to the corresponding values for the prototypical HKUST-1 (tbo-MOF-1), and are 42% and 20% higher than that of tbo-MOF-2. High-pressure methane adsorption isotherms revealed a high total gravimetric and volumetric CH4 uptakes, reaching 372 cm(3) (STP) g(-1) and 221 cm(3) (STP) cm(-3), respectively, at 85 bar and 298 K. The corresponding working capacities between 5 and 80 bar were found to be 294 cm(3) (STP) g(-1) and 175 cm(3) (STP) cm(-3) and are placed among the best performing MOFs for CH4 storage particularly at relatively low temperature. To gain insight on the mechanism accounting for the resultant enhanced CH4 storage capacity, molecular simulation study was performed and revealed the presence of very strong CH4 adsorption sites near the organic linker with similar adsorption energetics as the open metal sites. The present findings support the potential of tbo-MOFs based on the supermolecular building layer (SBL) approach as an ideal platform to further enhance the CH4 storage capacity via expansion and functionalization of the quadrangular pillars.

FoodOn: a harmonized food ontology to increase global food traceability, quality control and data integration.

Abstract: The construction of high capacity data sharing networks to support increasing government and commercial data exchange has highlighted a key roadblock: the content of existing Internet-connected information remains siloed due to a multiplicity of local languages and data dictionaries. This lack of a digital lingua franca is obvious in the domain of human food as materials travel from their wild or farm origin, through processing and distribution chains, to consumers. Well defined, hierarchical vocabulary, connected with logical relationships—in other words, an ontology—is urgently needed to help tackle data harmonization problems that span the domains of food security, safety, quality, production, distribution, and consumer health and convenience. FoodOn (http://foodon.org) is a consortium-driven project to build a comprehensive and easily accessible global farm-to-fork ontology about food, that accurately and consistently describes foods commonly known in cultures from around the world. FoodOn addresses food product terminology gaps and supports food traceability. Focusing on human and domesticated animal food description, FoodOn contains animal and plant food sources, food categories and products, and other facets like preservation processes, contact surfaces, and packaging. Much of FoodOn’s vocabulary comes from transforming LanguaL, a mature and popular food indexing thesaurus, into a World Wide Web Consortium (W3C) OWL Web Ontology Language-formatted vocabulary that provides system interoperability, quality control, and software-driven intelligence. FoodOn compliments other technologies facilitating food traceability, which is becoming critical in this age of increasing globalization of food networks.

Hund’s Rule-Driven Dzyaloshinskii-Moriya Interaction at 3d−5d Interfaces

Abstract: Using relativistic first-principles calculations, we show that the chemical trend of the Dzyaloshinskii-Moriya interaction (DMI) in $3d\text{\ensuremath{-}}5d$ ultrathin films follows Hund's first rule with a tendency similar to their magnetic moments in either the unsupported $3d$ monolayers or $3d\text{\ensuremath{-}}5d$ interfaces. We demonstrate that, besides the spin-orbit coupling (SOC) effect in inversion asymmetric noncollinear magnetic systems, the driving force is the $3d$ orbital occupations and their spin-flip mixing processes with the spin-orbit active $5d$ states control directly the sign and magnitude of the DMI. The magnetic chirality changes are discussed in the light of the interplay between SOC, Hund's first rule, and the crystal-field splitting of $d$ orbitals.