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Efficient synthesis recipes are needed both to streamline the manufacturing of complex materials and to accelerate the realization of theoretically predicted materials. Oftentimes the solid-state synthesis of multicomponent oxides is impeded by undesired byproduct phases, which can kinetically trap reactions in an incomplete non-equilibrium state. We present a thermodynamic strategy to navigate high-dimensional phase diagrams in search of precursors that circumvent low-energy competing byproducts, while maximizing the reaction energy to drive fast phase transformation kinetics. Using a robotic inorganic materials synthesis laboratory, we perform a large-scale experimental validation of our precursor selection principles. For a set of 35 target quaternary oxides with chemistries representative of intercalation battery cathodes and solid-state electrolytes, we perform 224 reactions spanning 27 elements with 28 unique precursors. Our predicted precursors frequently yield target materials with higher phase purity than when starting from traditional precursors. Robotic laboratories offer an exciting new platform for data-driven experimental science, from which we can develop new insights into materials synthesis for both robot and human chemists.

Electrochemically reducing CO2 to valuable fuels or feedstocks is recognized as a promising strategy to simultaneously tackle the crises of fossil fuel shortage and carbon emission. Sn-based catalysts have been widely studied for electrochemical CO2 reduction reaction (CO2 RR) to make formic acid/formate, which unfortunately still suffer from low activity, selectivity and stability. In this work, halogen (F, Cl, Br or I) was introduced into the Sn catalyst by a facile hydrolysis method. The presence of halogen was confirmed by a collection of ex situ and in situ characterizations, which rendered a more positive valence state of Sn in halogen-incorporated Sn catalyst as compared to unmodified Sn under cathodic potentials in CO2 RR and therefore tuned the adsorption strength of the key intermediate (*OCHO) toward formate formation. As a result, the halogen-incorporated Sn catalyst exhibited greatly enhanced catalytic performance in electrochemical CO2 RR to produce formate. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) This work was supported by the fund from NUS Green Energy Program (WBS:A-0005323-05-00), FRC MOE T1 (WBS:A-0009184-00-00), A*STAR LCERFI Project (Award ID: U2102d2011),Ministry of Education of Singapore (Tier 1: RG4/20, RG2/21 and Tier 2: MOET2EP10120-0002), Agency for Science, Technology and Research (AME IRG: A20E5c0080),the National Natural Science Foundation of China (Grant No. 22075195), and Photon Science Research Center for Carbon Dioxide.

Visual anomaly detection plays a crucial role in not only manufacturing inspection to find defects of products during manufacturing processes, but also maintenance inspection to keep equipment in optimum working condition particularly outdoors. Due to the scarcity of the defective samples, unsupervised anomaly detection has attracted great attention in recent years. However, existing datasets for unsupervised anomaly detection are biased towards manufacturing inspection, not considering maintenance inspection which is usually conducted under outdoor uncontrolled environment such as varying camera viewpoints, messy background and degradation of object surface after long-term working. We focus on outdoor maintenance inspection and contribute a comprehensive Maintenance Inspection Anomaly Detection (MIAD) dataset which contains more than 100K high-resolution color images in various outdoor industrial scenarios. This dataset is generated by a 3D graphics software and covers both surface and logical anomalies with pixel-precise ground truth. Extensive evaluations of representative algorithms for unsupervised anomaly detection are conducted, and we expect MIAD and corresponding experimental results can inspire research community in outdoor unsupervised anomaly detection tasks. Worthwhile and related future work can be spawned from our new dataset.

Noble metal electrocatalysts (e.g., Pt, Ru, etc.) suffer from sluggish kinetics of water dissociation for the electrochemical reduction of water to molecular hydrogen in alkaline and neutral pH environments. Herein, we found that an integration of Ru nanoparticles (NPs) on oxygen-deficient WO3-x manifested a 24.0-fold increase in hydrogen evolution reaction (HER) activity compared with commercial Ru/C electrocatalyst in neutral electrolyte. Oxygen-deficient WO3-x is shown to possess large capacity for storing protons, which could be transferred to the Ru NPs under cathodic potential. This significantly increases the hydrogen coverage on the surface of Ru NPs in HER and thus changes the rate-determining step of HER on Ru from water dissociation to hydrogen recombination. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) Published version We are grateful for the financial support from the National Key R&D Program of China (2021YFB3801600), the National Natural Science Foundation of China (21872121, 21908189), the Fundamental Research Funds for the Central Universities (2017XZZX002−16), Ministry of Education of Singapore (Tier 1: RG4/20 and Tier 2: MOET2EP10120-0002), and Agency for Science, Technology and Research (AME IRG: A20E5c0080).

High Entropy Alloys (HEAs) contain near equimolar amounts of five or more elements and are a compelling space for materials design. Great emphasis is placed on identifying HEAs that form a homogeneous solid-solution, but the design of such HEAs is hindered by the difficulty of navigating stability relationships in high-component spaces. Traditional phase diagrams use barycentric coordinates to represent composition axes, which require D = (N - 1) spatial dimensions to represent an N-component system, meaning that HEA systems with N > 4 components cannot be readily visualized. Here, we propose forgoing barycentric composition axes in favor of two energy axes: a formation-energy axis and a 'reaction energy' axis. These Inverse Hull Webs offer an information-dense 2D representation that successfully capture complex phase stability relationships in N > 4 component systems. We use our new diagrams to visualize the transition of HEA solid-solutions from high-temperature stability to metastability upon quenching, and identify important thermodynamic features that are correlated with the persistence or decomposition of metastable HEAs., 18 pages, 5 figures

In this paper, the dispatching problem of desalination load participation in distributed renewable energy consumption is taken as the research object, and the various characteristics of desalination system operation are analysed. According to the operating characteristics of the system, the operation constraints and optimal dispatching objectives of the multi-energy system with desalination load are proposed. An optimal dispatching model for distributed renewable energy consumption with desalination load participation was established and the linear simplex algorithm was used to solve the dispatching model according to the characteristics of the optimization model. The example shows that by optimizing the operation of the multi-energy system with seawater desalination load, it will help the local high-density distributed power supply to be consumed locally and improve certain economic benefits.

The first part of this dissertation starts from the introduction of the basic concepts and structures of OWL, and then it goes on to the methodology to develop OWL ontology. After OWL, we give a brief introduction of SOAP/WSDL based web service which is comprised of SOAP, WSDL and UDDI. However, WSDL descriptions by themselves do not provide sufficient information to ascertain the correct usage of the service. After illustrating the benefits of the richer service descriptions supported by OWL-S, it’s time to get into OWL-S which is an OWL-based Web Service Ontology, we illustrate the three concepts of OWL-S which consists of service profile, process model and service grounding. Then we continue to describe the OWL-S development paradigm and give a quick view on the semantic web service execution environments. Finally we conclude with a brief look at the OWL-S tools and extensions. The second part is about automatic execution of OWL-S semantic web service which first describes the problems in automatic executions of OWL-S semantic web service caused by the mismatches between OWL-S input/output classes and WSDL request/response messages. Then we use the approach of OWL-S/WSDL grounding to provide the mapping mechanism to solve the incompatibility between XML schema types and OWL classes when OWL-S descriptions use OWL classes as the input/output in the service model to invoke the web service in WSDL. In the design of automatic execution of OWL-S service, we come up with an OWL-S framework based on the generic OWL-S/WDSL grounding process to enable automatic OWL-S service execution and detailed runtime interactions occur in executing the OWL-S atomic process step by step. We also highlight the design issues and conclude with the limitations of OWL-S framework. The third part of this dissertation presents a derailed implementation of automatic execution of an OWL-S atomic process using OWL-S/WSDL grounding step by step, focusing primarily on the XSLT transformation of the OWL-S input class to the WSDL request messages at OWL-S request, and the WSDL response message to the OWL-S output class at OWL-S response. Master of Science

The consistency of the CIMS multiview model is a complicated problem. It takes an important role in CIMS life cycle. Based on the function-oriented multiview modeling approach, we further provided an object-oriented integrated multiview modeling approach. CIM system is composed of several objects linked in hierarchical control structure. The description of each object is a multiview description. We choose the most important four view-points: function, information, resource and dynamic view-point, and provide an conceptual model of OO integrated multiview modeling in CIMS, and a system integration approach.

The influence of varying concentrations of a transmembrane peptide, gramicidin A (gA), and cholesterol (Chol) on the passive permeation of p-methylhippuric acid (MHA) and alpha-carbamoyl-p-methylhippuric acid (CMHA) across egg-lecithin membranes (EPC) has been investigated in vesicle efflux experiments. Incorporation of 0.25 volume fraction of gA in its nonchannel conformation increased the permeability coefficient (Pm) for CMHA by a factor of 6.0 +/- 1.8 but did not alter Pm for MHA, a more lipophilic permeant. In contrast, incorporation of 0.26 volume fraction Chol with no added protein decreased the Pm values for both CMHA and MHA by similar factors of 4.2 +/- 1.1 and 3.5 +/- 1.2, respectively. A quantitative structure-transport model has been developed to account for the dependence of Pm on the membrane concentrations of gA and Chol in terms of induced changes in both membrane chain ordering and hydrophobicity. Chain ordering is assumed to affect Pm for both permeants similarly since they are comparable in molecular size, while changes in Pm ratios in the presence of gA or Chol are attributed to alterations in membrane hydrophobicity. Changes in lipid chain ordering were detected by monitoring membrane fluidity using fluorescence anisotropy of 1-[4-(trimethylamino)phenyl]-6-phenylhexa-1,3,5-triene incorporated into the membranes. The influence of additives on membrane hydrophobicity, which governs Pm ratios through effects on solute partitioning into the barrier domain, were rationalized within the framework of regular solution theory using solubility parameters as a measure of membrane hydrophobicity. Fits of the Pm ratios using the theoretical model yielded solubility parameters for gA and Chol in EPC membranes of 13.2 and 7.7 (cal/ml)(1/2), respectively, suggesting that gA decreases the barrier domain hydrophobicity while Chol has a minimal effect on barrier hydrophobicity. After correcting for barrier domain hydrophobicity, permeability decrements due to membrane ordering induced by gA or Chol were found to exhibit a strong correlation with membrane order as predicted by free-surface-area theory, regardless of whether gA or Chol is used as the ordering agent.