The field of heterogeneous photocatalysis has expanded rapidly in the last four decades, having undergone various evolutionary phases related to energy and the environment. The two most significant ...applications of photocatalysis are geared toward solar water splitting and the purification of air and water. Notably, the interdisciplinary nature of the field has increased significantly, incorporating semiconductor physics, surface sciences, photo and physical chemistry, materials science, and chemical engineering. Whereas this forms the basis on which the field continues to grow, adequate bridging of multidisciplinary knowledge remains essential. By recalling some of the classical fundamentals of photocatalysis, this Perspective provides contemporary views on heterogeneous photochemical conversion, encompassing charge transport characteristics, radical chemistry and organic degradation mechanisms, photocatalyst design, and photoreactor engineering.
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IJS, KILJ, NUK, PNG, UL, UM
Bioinspired nanotopography artificially fabricated on titanium surfaces offers a solution for the rising issue of postoperative infections within orthopedics. On a small scale, hydrothermal etching ...has proven to deliver an effective antimicrobial nanospike surface. However, translation to an industrial setting is limited by the elevated synthesis temperature (150 °C) and associated equipment requirements. Here, for the first time, we fabricate surface nanostructures using comparatively milder synthesis temperatures (75 °C), which deliver physicochemical properties and antimicrobial capability comparable to the high-temperature surface. Using a KOH etchant, the simultaneous formation of titania and titanate crystals at both temperatures produces a one-dimensional nanostructure array. Analysis indicated that the formation mechanism comprises dissolution and reprecipitation processes, identifying the deposited titanates as hydrated layered tetra-titanates (K2Ti4O9·nH2O). A proposed nanospike formation mechanism was confirmed through the identification of a core and outer shell for individual nanostructures, primarily comprised of titanates and titania, respectively. Etching conditions dictated crystalline formation, favoring a thicker titanate core for nanorods under higher synthesis temperatures and etchant concentrations. A bactericidal investigation showed the efficacy against Gram-negative bacteria for a representative low-temperature nanosurface (34.4 ± 14.4%) was comparable to the higher temperature nanosurface (34.0 ± 17.0%), illustrating the potential of low-temperature hydrothermal synthesis. Our results provide valuable insight into the applicability of low-temperature etching protocols that are more favorable in large-scale manufacturing settings.
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Ordered meso/macroporous metal oxides have gained increasing attention in heterogeneous catalysis arising from their large surface areas and pore volumes, elevated catalytic activity and good thermal ...stability. Compared to nonporous metal oxides, their most prominent feature is the ability to interact with molecules not only at their exterior surface but also within the large interior surface of the material. The past decade has witnessed substantial advances in the synthesis of new porous metal oxides with ordered structures for use in a wide range of applications. By recalling some of the classical fundamentals of porous materials, this review examines the recent developments in ordered meso- and macro-porous metal oxide catalysts for heterogeneous catalysis. Additionally, we outline the current challenges in the field of nanoparticle-based catalysis, including the role played by the morphology (size, shape, and porosity) of ordered meso/macroporous metal oxides, and provide a perspective on the need for further advances in porous materials so that their contribution to heterogeneous catalysis can continue to expand.
The present review article highlights the preparation, characterization, properties, and recent developments in porous metal oxide catalysts for heterogeneous catalysis.
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•Alloyed NiCo catalysts outperform monometallic Ni and Co in activity and stability.•Ni is more selective than Co towards CH4 cracking and CO2 activation.•Co is more selective than Ni ...toward the Boudouard Reaction.
Nickel and cobalt-based catalysts are very promising candidates for the dry reforming of methane, but their role in regulating catalyst selectivity has thus far been overlooked. Here we report the significant impact that catalyst selectivity has on the performance of Ni and Co catalysts for the dry reforming of methane. The role of Ni and Co in defining catalyst selectivity was examined via in-depth investigations into the tendency of catalysts towards the Boudouard, methane cracking and reverse water gas shift side reactions. Decoupling the side reactions demonstrated that Co deposits have a high affinity for the removal of carbon species via oxidation, while Ni is more active towards CH4 decomposition. Thereby superior catalytic performance is accessed via a combination of the high activity of Ni towards CH4 with the stabilising effect and carbon-resistance of Co. Characterisation of the materials illustrated the formation of well-dispersed NiCo alloys on the FSP-alumina, with the resulting strong bimetallic interactions fuelling enhanced catalytic performance via suppression of catalyst selectivity of Co towards the Boudouard reaction and Ni towards methane cracking.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Recent advances in traffic monitoring systems have made real-time traffic velocity data ubiquitously accessible for drivers. This paper develops a traffic data-enabled predictive energy management ...framework for a power-split plug-in hybrid electric vehicle (PHEV). Compared with conventional model predictive control (MPC), an additional supervisory state of charge (SoC) planning level is constructed based on real-time traffic data. A power balance-based PHEV model is developed for this upper level to rapidly generate battery SoC trajectories that are utilized as final-state constraints in the MPC level. This PHEV energy management framework is evaluated under three different scenarios: 1) without traffic flow information; 2) with static traffic flow information; and 3) with dynamic traffic flow information. Numerical results using real-world traffic data illustrate that the proposed strategy successfully incorporates dynamic traffic flow data into the PHEV energy management algorithm to achieve enhanced fuel economy.
Optical filters can be used to increase solar conversion efficiency in hybrid photovoltaic/thermal (PV/T) collectors by partitioning incident light into two spectra: one desirable for direct ...electrical conversion and one for thermal collection. This article is the first to present both modeled and experimental results for a spectrally-tailorable, multi-particle nanofluid filter positioned between a concentrated light source and a silicon cell. The nanofluid is composed of suspended core–shell silver-silica (Ag–SiO2) nanodiscs and carbon nanotubes (CNTs) in water. The core–shell particles were specifically synthesized and designed to absorb the majority of the visible spectrum, while transmitting the light which corresponds to the PV cell. The silver nanodiscs strongly absorb visible light with minimal scattering, whereas the silica shell maintains the shape and absorption spectrum of the silver cores. Alternatively, low-concentration carbon nanotube (CNT) solutions were used to enhance absorption (particularly of ultra-violet light) and to provide a comparison for selective filters versus broadband absorbers. Varying dilutions of the Ag–SiO2 nanofluid are compared to solutions diluted with dispersed CNTs. The CNTs enhance the heating rate of the nanofluid with the caveat of non-selective light absorption, which reduces the electrical output. Ag–SiO2 nanofluids (0.026wt%) increased combined efficiencies by 30% compared to the base fluid filter alone. For a small additional cost of <$1/L of nanofluid, the developed system represents a highly efficient hybrid generator which can be dynamically tailored to meet variable thermal energy and electricity prices.
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•Selectively absorbing nanofluids were fabricated for hybrid PV/thermal collectors.•Core–shell silver-silica nanodiscs and carbon nanotubes were suspended in water.•Temperature and photocurrent were measured for fluid filters and silicon PV.•A merit function was used to evaluate the combined power output for nanofluids.•Optical efficiencies of up to 58% can be achieved for <$1/L of nanofluid.
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Dramatically increased CO
2
concentration from several point sources is perceived to cause severe greenhouse effect towards the serious ongoing global warming with associated climate destabilization, ...inducing undesirable natural calamities, melting of glaciers, and extreme weather patterns. CO
2
capture and utilization (CCU) has received tremendous attention due to its significant role in intensifying global warming. Considering the lack of a timely review on the state-of-the-art progress of promising CCU techniques, developing an appropriate and prompt summary of such advanced techniques with a comprehensive understanding is necessary. Thus, it is imperative to provide a timely review, given the fast growth of sophisticated CO
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capture and utilization materials and their implementation. In this work, we critically summarized and comprehensively reviewed the characteristics and performance of both liquid and solid CO
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adsorbents with possible schemes for the improvement of their CO
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capture ability and advances in CO
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utilization. Their industrial applications in pre- and post-combustion CO
2
capture as well as utilization were systematically discussed and compared. With our great effort, this review would be of significant importance for academic researchers for obtaining an overall understanding of the current developments and future trends of CCU. This work is bound to benefit researchers in fields relating to CCU and facilitate the progress of significant breakthroughs in both fundamental research and commercial applications to deliver perspective views for future scientific and industrial advances in CCU.
This review covers the sustainable development of advanced improvements in CO
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capture and utilization.
This paper examines the problem of optimally splitting driver power demand among the different actuators (i.e., the engine and electric machines) in a plug-in hybrid electric vehicle (PHEV). Existing ...studies focus mostly on optimizing PHEV power management for fuel economy, subject to charge sustenance constraints, over individual drive cycles. This paper adds three original contributions to this literature. First, it uses stochastic dynamic programming to optimize PHEV power management over a distribution of drive cycles, rather than a single cycle. Second, it explicitly trades off fuel and electricity usage in a PHEV, thereby systematically exploring the potential benefits of controlled charge depletion over aggressive charge depletion followed by charge sustenance. Finally, it examines the impact of variations in relative fuel-to-electricity pricing on optimal PHEV power management. The paper focuses on a single-mode power-split PHEV configuration for mid-size sedans, but its approach is extendible to other configurations and sizes as well.
This paper presents a new battery state-of-charge (SOC) estimation method for lithium-ion batteries (LIBs) based on a nonlinear fractional model with incommensurate differentiation orders. A ...continuous frequency distributed model is used to describe the incommensurate fractional system. A Luenberger-type observer is designed for battery SOCestimation. The observer gain that can stabilize the zero equilibrium of the estimation error system is derived by Lyapunov's direct method. The proposed SOC observer is examined using the real-time experimental data of LIBs. The robustness of the observer under different test conditions, including different aging levels, different driving cycles, and different cells, is also presented.
Colletotrichum tanaceti is an emerging foliar fungal pathogen of commercially grown pyrethrum (Tanacetum cinerariifolium). Despite being reported consistently from field surveys in Australia, the ...molecular basis of pathogenicity of C. tanaceti on pyrethrum is unknown. Herein, the genome of C. tanaceti (isolate BRIP57314) was assembled de novo and annotated using transcriptomic evidence. The inferred putative pathogenicity gene suite of C. tanaceti comprised a large array of genes encoding secreted effectors, proteases, CAZymes and secondary metabolites. Comparative analysis of its putative pathogenicity gene profiles with those of closely related species suggested that C. tanaceti likely has additional hosts to pyrethrum. The genome of C. tanaceti had a high repeat content and repetitive elements were located significantly closer to genes inferred to influence pathogenicity than other genes. These repeats are likely to have accelerated mutational and transposition rates in the genome, resulting in a rapid evolution of certain CAZyme families in this species. The C. tanaceti genome showed strong signals of Repeat Induced Point (RIP) mutation which likely caused its bipartite nature consisting of distinct gene-sparse, repeat and A-T rich regions. Pathogenicity genes within these RIP affected regions were likely to have a higher evolutionary rate than the rest of the genome. This "two-speed" genome phenomenon in certain Colletotrichum spp. was hypothesized to have caused the clustering of species based on the pathogenicity genes, to deviate from taxonomic relationships. The large repertoire of pathogenicity factors that potentially evolve rapidly due to the plasticity of the genome, indicated that C. tanaceti has a high evolutionary potential. Therefore, C. tanaceti poses a high-risk to the pyrethrum industry. Knowledge of the evolution and diversity of the putative pathogenicity genes will facilitate future research in disease management of C. tanaceti and other Colletotrichum spp.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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