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Quantifying incident impacts and identifying influential features in urban traffic networks
No full textTraffic incidents are a common occurrence in urban traffic networks, but predicting their impacts is challenging because of network complexity and the dynamic spatial and temporal dependencies inherent in traffic data. Nevertheless, the prediction of traffic incident impacts is crucial for global positioning systems to provide drivers with real-time route recommendations for bypassing congested roads. To this end, we formulated nonrecurrent congestion measures to quantify these impacts and developed a new method to identify the influential features that locally affect individual incidents. Because traffic incident impacts are determined by a complex entanglement of local features, a meaningful feature that can explain their impacts globally may not exist. Consequently, to identify all influential local features, we applied the local interpretable model-agnostic explanations (LIME) technique to the proposed nonrecurrent congestion measures. The proposed method was validated using real user trajectory data and incident data provided by the NAVER Corporation and the Korean National Police Agency, respectively
Hydrogen production by the catalytic decomposition of ammonia over a Ru/SiCeOx catalyst: The synergistic effect of Si addition
No full textControlling active metal-support interaction is critical in the catalytic decomposition of ammonia (NH3). In this study, we investigated the generation of oxygen vacancies in the SiCeOx support by Si addition and the increase in catalytic performance for the decomposition of NH3 by their interaction with Ru. The Si content in the Ru/ SiCeOx catalysts was controlled by glassware elution during the precipitation of Ce(NO3)3 at a high pH level (10.5) by applying different aging temperatures and times. The formation of oxygen vacancies by the insertion of Si4+ into the CeO2 lattice was characterized by O2-pulse experiments as well as Raman and X-ray photoelectron spectroscopy analyses. The effect of oxygen vacancies on the adsorption strengths of hydrogen and nitrogen on Ru was characterized by H2-temperature-programmed reduction and NH3-temperature-programmed desorption. The correlation between NH3 conversion, oxygen vacancy content, and nitrogen desorption temperature was experimentally proven
Regulating the Sequence Structure of Conjugated Block Copolymers Enables Large-Area Single-Component Organic Solar Cells with High Efficiency and Stability
No full textSingle-component organic solar cells (SCOSCs) based on conjugated block copolymers (CBCs) by covalently bonding a polymer donor and polymer acceptor become more and more appealing due to the formation of a favorable and stable morphology. Unfortunately, a deep understanding of the effect of the assembly behavior caused by the sequence structure of CBCs on the device performance is still missing. Herein, from the aspect of manipulating the sequence length and distribution regularity of CBCs, we synthesized a series of new CBCs, namely D18(20)-b-PYIT, D18(40)-b-PYIT and D18(60)-b-PYIT by two-pot polymerization, and D18(40)-b-PYIT(r) by traditional one-pot method. It is observed that precise manipulation of sequence length and distribution regularity of the polymer blocks fine-tunes the self-assembly of the CBCs, optimizes film morphology, improves optoelectronic properties, and reduces energy loss, leading to simultaneously improved efficiency and stability. Among these CBCs, the D18(40)-b-PYIT-based device achieves a high efficiency of 13.4 % with enhanced stability, which is an outstanding performance among SCOSCs. Importantly, the regular sequence distribution and suitable sequence length of the CBCs enable a facile film-forming process of the printed device. For the first time, the blade-coated large-area rigid/flexible SCOSCs are fabricated, delivering an impressive efficiency of 11.62 %/10.73 %, much higher than their corresponding binary devices
Determining the Effect of Cation (Ti/Zr) Doping in Bismuth Oxide for Electrochemical CO2 Reduction to Formic Acid: A DFT Study
No full textFirst-principles-based density functional theory (DFT)calculationswere used to explore the electrochemical CO2 reduction(ECR) activity of cation-doped Bi2O3. We studiedthe ECR reaction over pure and doped Bi2O3 (100)surfaces and demonstrated Gibbs free energy diagrams of HCOOH formationvia COOH and HCOO pathways. Compared with pure bismuth oxide, dopingcan alter the rate-determining step and reduce the Gibbs free energyfrom 2.98 to 0.11 eV. The CO2 reduction activity was foundto be most productive on the TiZr-Bi2O3 surface with onset potentials of -0.23 and 0.55 V via theCOOH and HCOO pathways, respectively. The probability of CO formationthrough the ECR reaction was also investigated using Gibbs free energycalculations, and it was found that Bi2O3, Ti-Bi2O3, Zr-Bi2O3, andTiZr-Bi2O3 displayed insufficient ECRactivity to produce CO. We also compared the selectivity of the ECRreaction and the hydrogen evolution reaction (HER) to demonstratethe practicality of the electrocatalysts
Death of the Young, Death of the Newborn, and Death of the Old
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Neurobehavioral impacts of a social observer on risky decision-making in cigarette smokers
No full textFast fabrication technique for high-quality van der Waals heterostructures using inert shielding gas environment
No full text2D materials based on van der Waals heterostructures have remarkable applications in electronic de-vices. However, trapped contaminations between the interface heterostructure layers during fabrication pro-cesses degrade the device performance. Here, we report a novel fabrication method to prevent contamination of the device from air impurities to obtain atomically clean interfaces using an Argon shielding gas environment. Large-area graphene encapsulated with hexagonal boron nitride, approximately-12,637 & mu;m2, has been fabri-cated. Using the proposed methodology, high graphene mobility up to 600 000 cm2V- 1s- 1 at room temperature has been achieved. The theoretical analysis combined with a molecular dynamic simulation model was utilized to improve the dry transfer technique for large-scale fabrication of 2D materials
A study of electron source preference and its impact on hydrogen production in microbial electrolysis cells fed with synthetic fermentation effluent
No full textFermentation effluents from organic wastes contain simple organic acids and ethanol, which are good electron sources for exoelectrogenic bacteria, and hence are considered a promising substrate for hydrogen production in microbial electrolysis cells (MECs). These fermentation products have different mechanisms and thermodynamics for their anaerobic oxidation, and therefore the composition of fermentation effluent significantly influences MEC performance. This study examined the microbial electrolysis of a synthetic fermentation effluent (containing acetate, propionate, butyrate, lactate, and ethanol) in two-chamber MECs fitted with either a proton exchange membrane (PEM) or an anion exchange membrane (AEM), with a focus on the utilization preference between the electron sources present in the effluent. Throughout the eight cycles of repeated batch operation with an applied voltage of 0.8 V, the AEM-MECs consistently outperformed the PEM-MECs in terms of organic removal, current generation, and hydrogen production. The highest hydrogen yield achieved for AEM-MECs was 1.26 L/g chemical oxygen demand (COD) fed (approximately 90% of the theoretical maximum), which was nearly double the yield for PEM-MECs (0.68 L/g COD fed). The superior performance of AEM-MECs was attributed to the greater pH imbalance and more acidic anodic pH in PEM-MECs (5.5-6.0), disrupting anodic respiration. Although butyrate is more thermodynamically favorable than propionate for anaerobic oxidation, butyrate was the least favored electron source, followed by propionate, in both AEM- and PEM-MECs, while ethanol and lactate were completely consumed. Further research is needed to better comprehend the preferences for different electron sources in fermentation effluents and enhance their microbial electrolysis
Deciphering the kinetics and pathway of lindane biodegradation by novel soil ascomycete fungi for its implication in bioremediation
No full textLindane, an organochlorine pesticide, negatively affects living beings and the ecosystem. In this study, the potential of 9 Ascomycetes fungi, isolated from an hexachlorocyclohexane dumpsite soil, was tested for biodegradation of lindane. The strain Pleurostoma richardsiae (FN5) showed lindane biodegradation rate constant (K value) of 0.144 d-1 and a half-life of 4.8d. The formation of intermediate metabolites upon lindane degradation including & gamma;-pentachlorocyclohexene, 2,4-dichlorophenol, phenol, benzene, 1,3- cyclohexadiene, and benzoic acid detected by GC-MS and the potential pathway adopted by the novel fungal strain FN5 for lindane biodegradation has been elucidated. The study of gene profiles with reference to linA and linB in strain FN5 confirmed the same protein family with the reported heterologs from other fungal strains in the NCBI database. This study for the first time provides a thorough understanding of lindane biodegradation by a novel soil-borne Ascomycota fungal strain for its possible application in field-scale bioremediation
Influence of structural transformation on guest exchange behavior in the sII hydrate-(CO2 + N-2) replacement for energy recovery and CO2 sequestration
No full textIn this study, the guest exchange behavior in the sII (CH4 + C3H8) hydrate - (CO2 + N-2) replacement at various CO2 concentrations was experimentally investigated to elucidate the influence of the structural transformation of the initial sII hydrate on the replacement efficiency at different feed gas compositions and injecting pressures. The extent of replacement, structural identification, and cage occupancy of guest molecules in the replaced hydrates were determined by a combination of gas chromatography (GC), powder X-ray diffraction (PXRD), and 13C NMR spectroscopy. The experimental results demonstrated that injecting feed gas with higher CO2 concentrations (%CO2) at a higher partial pressure of CO2 (PCO2) resulted in a higher weight fraction of sI hydrates (a greater degree of structural transformation from sII to sI) after replacement and consequently, higher replacement efficiency. The newly formed sI hydrates after replacement were primarily composed of CO2 and N-2. The guest-inclusion behavior in the small (5(12)) cages of the sII hydrates after replacement, as revealed by Rietveld refinement of the PXRD patterns, had a dominant influence on the total CO2/N-2 ratios in the replaced hydrates. The findings of this study offer valuable insights into the guest exchange mechanism occurring in sII hydrates during flue gas injection and can aid in estimating the optimal compositions of flue gas for energy recovery and CO2 sequestration through guest replacement in natural gas hydrates