Arranging ionic liquids (ILs) with long‐range order can not only enhance their performance in a desired application, but can also help elucidate the vital between structure and properties. However, ...this is still a challenge and no example has been reported to date. Herein, we report a feasible strategy to achieve a crystalline IL via coordination self‐assembly based reticular chemistry. IL1MOF, was prepared by designing an IL bridging ligand and then connecting them with metal clusters. IL1MOF has a unique structure, where the IL ligands are arranged on a long‐range ordered framework but have a labile ionic center. This structure enables IL1MOF to break through the typical limitation where the solid ILs have lower proton conductivity than their counterpart bulk ILs. IL1MOF shows 2–4 orders of magnitude higher proton conductivity than its counterpart IL monomer across a wide temperature range. Moreover, by confining the IL within ultramicropores (<1 nm), IL1MOF suppresses the liquid–solid phase transition temperatures to lower than −150 °C, allowing it to function with high conductivity in a subzero temperature range.
A reticular chemistry based strategy opens a facile toolbox for designing liquid molecules with long‐rang‐ordered framework of MOF. IL1MOF is the first crystalline ionic liquid (IL) combining a balance of good mechanical properties and high conductivity. It expands the use of IL electrolytes to an low temperature region.
This study applies a network approach to develop a model that highlights the role of resource acquisition through networks as an important mediating mechanism through which entrepreneurial ...orientation influences firm performance. This approach provides an alternative explanation for the divergent findings of the EO-performance relationship. We also investigate how business and political ties, differently and configurationally, shape the relationship between EO and network resource acquisition. Empirical findings from a study of 251 firms provide general support for the hypotheses, highlighting the unique value of leveraging a network approach to reconsider the performance-enhancing mechanism of entrepreneurial orientation.
To attain the optimal capacitive deionization (CDI) performance for brackish water desalination, an electrode should possess high electrical conductivity, large surface area, hierarchically porous ...carbons with three-dimensional (3D) interconnection which can provide efficient pathways for ion and electron transfer. Herein we demonstrate a novel route to prepare a hierarchically porous 3D architectural graphene by using a combination of microwave treatment and H2O2-assisted hydrothermal method. The physicochemical and electrochemical properties of prepared 3D porous graphene are identified by scanning/transmission electron microscopy, X-ray based spectroscopies, Raman, nitrogen adsorption-desorption, cyclic voltammetry and electrochemical impendence spectroscopy. The desalination tests are carried out by using a batch-mode CDI at 1.4 V in a 500 ppm NaCl solution. Experimental results show that 3D porous graphene has a superior specific capacitance (190 F g−1) and ultrahigh electrosorption capacity (21.58 mg g−1). This unique hierarchically porous 3D graphene which exhibits good electrical conductivity, efficient ion transport and lower charge transfer resistance could be one of promising electrodes for CDI in the practical applications.
•A hierarchically porous 3D graphene was prepared by a facile and cost-effective route.•Hierarchical and 3D structure can be created by microwave and H2O2-hydrothermal treatments.•The CDI capacity of prepared samples can reach 21.58 mg g−1 at 1.4 V in a 500 ppm NaCl solution.•This is due to the higher mesoporosity, capacitance and unique 3D hierarchical structure.•The surpassing performance enables hierarchically 3D graphene practical applications.
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•Biochars are potential sustainable precursors for activated carbon production.•Physical activation and chemical activation are applied in the production process.•Production ...parameters affect the properties of resultant activated carbon.•Multiple applications in environmental protection and energy storage are reviewed.•Future perspectives about biochar activation and applications are highlighted.
There is a growing interest of the scientific community on production of activated carbon using biochar as potential sustainable precursors pyrolyzed from biomass wastes. Physical activation and chemical activation are the main methods applied in the activation process. These methods could have significantly beneficial effects on biochar chemical/physical properties, which make it suitable for multiple applications including water pollution treatment, CO2 capture, and energy storage. The feedstock with different compositions, pyrolysis conditions and activation parameters of biochar have significant influences on the properties of resultant activated carbon. Compared with traditional activated carbon, activated biochar appears to be a new potential cost-effective and environmentally-friendly carbon materials with great application prospect in many fields. This review not only summarizes information from the current analysis of activated biochar and their multiple applications for further optimization and understanding, but also offers new directions for development of activated biochar.
A microwave-assisted hydrothermal preparation of heterostructured graphitic carbon nitride/bismuth tungsten oxide/reduced graphene oxide nanocomposites (denoted as GBR-T, T = microwave irradiation ...time) is performed. The prepared GBR-T photocatalysts are identified by employing X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), time-resolved photoluminescence (TRPL) and nitrogen adsorption-desorption isotherms. The photocatalytic performance of these GBR-T is evaluated by the photocatalytic degradation of ibuprofen (IBP) under the visible light (λ > 420 nm) and solar light irradiation. Among all prepared photocatalysts, ca. 93% of IBP photodegradation can be achieved with a degradation rate constant (k) of 0.011 min−1 under visible-light irradiation upon the optimal microwave-assisted reaction time of 60 min. The improvement is primarily attributable to the higher crystallization degree, specific surface area and increased charge transfer efficiency as verified by XRD, nitrogen adsorption-desorption isotherms and TRPL, respectively. The photocatalytic performance of this catalyst is further enhanced in the photodecomposition of IBP (ca. 98.6%) under sun light irradiation. The electron spin resonance (ESR) and liquid chromatography-mass/mass spectrometry (LC–MS/MS) studies show that the superoxide radicals and hydroxyl radicals are the dominant active species in the photocomposition of IBP and degradation intermediates are formed through three probable photodegradation pathways. This investigation provides a simple way to prepare triple 2D heterojuction photocatalysts which could be effectively used in the advanced oxidation process for removal of emerging contaminants in wastewater by using renewable energy.
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•Heterojuncted GBR-T (T = irradiation time) is prepared by a simple microwave-assisted method.•The higher activity of GBR-60 is due to the higher crystallization, SBET and charge transfer.•IBP photodegradation intermediates and reaction mechanisms are further investigated.•∙OH is the donimant active species in the photodegradation of IBP by GBR-60 under visible light.
•Species of bacteria and fungi that dealt with PAHs and heavy metals were reviewed.•Factors affecting bioremediation of PAHs and heavy metals were discussed.•Bioremediation mechanisms of PAHs and ...heavy metals were elucidated.•Potential research needs for this field were discussed.
In recent years, knowledge in regard to bioremediation of combined pollution of polycyclic aromatic hydrocarbons (PAHs) and heavy metals by bacteria and fungi has been widely developed. This paper reviews the species of bacteria and fungi which can tackle with various types of PAHs and heavy metals entering into environment simultaneously or successively. Microbial activity, pollutants bioavailability and environmental factors (e.g. pH, temperature, low molecular weight organic acids and humic acids) can all affect the bioremediation of PAHs and heavy metals. Moreover, this paper summarizes the remediation mechanisms of PAHs and heavy metals by microbes via elucidating the interaction mechanisms of heavy metals with heavy metals, PAHs/PAHs metabolites with PAHs and PAHs with heavy metals. Based on the above reviews, this paper also discusses the potential research needs for this field.
Engineering, controlling, and simulating quantum dynamics is a strenuous task. However, these techniques are crucial to develop quantum technologies, preserve quantum properties, and engineer ...decoherence. Earlier results have demonstrated reservoir engineering, construction of a quantum simulator for Markovian open systems, and controlled transition from Markovian to non-Markovian regime. Dephasing is an ubiquitous mechanism to degrade the performance of quantum computers. However, all-purpose quantum simulator for generic dephasing is still missing. Here, we demonstrate full experimental control of dephasing allowing us to implement arbitrary decoherence dynamics of a qubit. As examples, we use a photon to simulate the dynamics of a qubit coupled to an Ising chain in a transverse field and also demonstrate a simulation of nonpositive dynamical map. Our platform opens the possibility to simulate dephasing of any physical system and study fundamental questions on open quantum systems.
This paper presents a deep learning-based bridge condition rating data modeling approach using selected data from the National Bridge Inventory (NBI) database. The objective of this research is to ...develop a data-driven approach that enables prediction of future conditions of highway bridge components from historical inspection data. The problem is solved by training a Convolutional Neural Network (CNN) model with online available NBI data. One prominent feature of the CNN model is that if well-trained it can represent the high dimensional data in the dataset abstractions for which conventional mathematical models may be difficult to describe. A case study of Maryland and Delaware highway bridges using historical data (1992-2017) sourced from the NBI database has been performed to demonstrate the proposed method. CNN models for three primary components of these highway bridges including the deck, superstructure, and substructure have been established. Optimization of model parameters is achieved through a parametric study. Research findings suggest that the deep learning model offers a promising tool as a data-driven condition forecasting approach for bridge components with a demonstrated prediction accuracy over 85%.
Petroleum hydrocarbon pollution is a global problem. However, the effects of different petroleum pollution levels on soil microbial communities and ecological functions are still not clear. In this ...study, we analyzed the changes in microbial community structures and carbon and nitrogen transformation functions in oil-contaminated soils at different concentrations by chemical analysis, high-throughput sequencing techniques, cooccurrence networks, and KEGG database comparison functional gene annotation. The results showed that heavy petroleum concentrations (petroleum concentrations greater than 20,000 mg kg−1) significantly decreased soil microbial diversity (p = 0.01), soil microbiome network complexity, species coexistence patterns, and prokaryotic carbon and nitrogen fixation genes. In medium petroleum contamination (petroleum concentrations of between 4000 mg kg−1 and 20,000 mg kg−1), microbial diversity (p > 0.05) and carbon and nitrogen transformation genes showed no evident change but promoted species coexistence patterns. Heavy petroleum contamination increased the Proteobacteria phylum abundance by 3.91%–57.01%, while medium petroleum contamination increased the Actinobacteria phylum abundance by 1.69%–0.26%. The results suggested that petroleum concentrations played a significant role in shifting soil microbial community structures, ecological functions, and species diversities.
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•Heavy petroleum contamination lead to increase of Proteobacteria phylum.•The microbial alpha and beta diversities are reduced in the heavy-polluted soil.•The abundances of nitrogen related pathway genes decrease in the heavy contaminated soil.•The correlations of microorganisms increase in the medium petroleum-polluted soil.•Actinobacteria phylum is increased by medium petroleum levels.
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