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29 pages, 3253 KiB  
Article
Green Infrastructure: Opinion Mining and Construction Material Reuse Optimization Portal
by Arturas Kaklauskas, Elisabete Teixeira, Yiannis Xenidis, Anastasia Tzioutziou, Lorcan Connolly, Sarunas Skuodis, Kestutis Dauksys, Natalija Lepkova, Laura Tupenaite, Loreta Kaklauskiene, Simona Kildiene, Jurgita Zidoniene, Virginijus Milevicius and Saulius Naimavicius
Buildings 2025, 15(13), 2362; https://doi.org/10.3390/buildings15132362 - 5 Jul 2025
Viewed by 344
Abstract
More and more sustainability data are being generated from green buildings and from urban and civil infrastructures. For decades, various systems have been developed, and their data have been collected and stored. More detailed, real-time, and cost-effective data, however, are still in short [...] Read more.
More and more sustainability data are being generated from green buildings and from urban and civil infrastructures. For decades, various systems have been developed, and their data have been collected and stored. More detailed, real-time, and cost-effective data, however, are still in short supply. To address this gap, one of the main objectives of the present study is to propose the GREEN method for opinion analysis to support the development of green infrastructure. Google Search was used to gather substantial amounts of information reflecting the views of both ordinary individuals and professionals regarding the benefits, drawbacks, challenges, and limitations of green infrastructure. Previously, however, such data have not been employed to improve green infrastructure by means of opinion analytics. The GREEN method was developed for the analysis of green infrastructure (GI) and its context, enabling multiple-criteria, neural network, correlation, and regression analyses across micro-, meso-, and macro-environmental scales. A total of 788 global regression (R2 = 0.997) and neural network (R2 = 0.596) GREEN models were developed and tested. In addition, 34 regression models for 12 (R2 = 0.817) and 20 (R2 = 0.511) cities were created for the world and separate cities (Munich (R2 aver = 0.801) and London (R2 aver = 0.817)). The GREEN method is a new way to analyze stakeholder opinions on sustainable green infrastructure and its context. With the objective of making green infrastructure more efficient and reducing carbon emissions, the Construction Material Reuse Optimization (SOLUTION) Portal was created as part of this research. The portal generates multiple options and proposes optimal alternatives for reused construction products. The results show that the GREEN method and SOLUTION Portal are reliable tools for evidence-based and rational green infrastructure development. Full article
(This article belongs to the Section Architectural Design, Urban Science, and Real Estate)
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22 pages, 8549 KiB  
Article
A Dissipative Particle Dynamics Study on the Formation of the Water-In-Petroleum Emulsion: The Contribution of the Oil
by Peng Shi, Murtaja Hamid Oudah Ogail, Xinxin Feng, Shenwen Fang, Ming Duan, Wanfen Pu and Rui Liu
Appl. Sci. 2025, 15(10), 5422; https://doi.org/10.3390/app15105422 - 13 May 2025
Viewed by 450
Abstract
High internal phase emulsions (HIPEs), in which the dispersed water phase exceeds 70%, play a critical role in enhancing oil recovery through in situ permeability modification. However, their stability remains a major challenge due to frequent phase inversion and coalescence. In this study, [...] Read more.
High internal phase emulsions (HIPEs), in which the dispersed water phase exceeds 70%, play a critical role in enhancing oil recovery through in situ permeability modification. However, their stability remains a major challenge due to frequent phase inversion and coalescence. In this study, the formation and stabilization mechanisms of water-in-oil HIPEs were investigated using a multiscale modeling approach that combines dissipative particle dynamics (DPD), molecular dynamics (MD), and density functional theory (DFT). Fourteen oil types and six polyaromatic emulsifiers with varying side-chain configurations and polar functional groups were modeled. Emulsifier performance was evaluated across 42 DPD-simulated systems with 70% and 80% water content. The results showed that emulsifiers with moderate dipole moments (~6 Debye) and spatially distributed heteroatoms achieved the most stable emulsion structures, forming continuous interfacial films or micelle-bridged networks. In contrast, emulsifiers with weak polarity (<1 Debye) or excessive stacking tendencies failed to prevent phase separation. The HOMO–LUMO energy gap and cohesive energy density (CED) were found to be poor predictors of emulsification performance. Four distinct stabilization mechanisms were identified, including interfacial film co-construction with oils and steric stabilization via side-chain architecture. The findings demonstrate that dipole moment is a reliable molecular descriptor for emulsifier design. This study provides a theoretical foundation for the rational development of high-performance emulsifiers in petroleum-based HIPE systems and highlights the potential of multiscale simulations in guiding formulation strategies. Full article
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42 pages, 9592 KiB  
Article
Air Route Network Planning Method of Urban Low-Altitude Logistics UAV with Double-Layer Structure
by Zhuolun Li, Shan Li, Jian Lu and Sixi Wang
Drones 2025, 9(3), 193; https://doi.org/10.3390/drones9030193 - 6 Mar 2025
Cited by 1 | Viewed by 1696
Abstract
With the rapid development of e-commerce, logistics UAVs (unmanned aerial vehicles) have shown great potential in the field of urban logistics. However, the large-scale operation of logistics UAVs has brought challenges to air traffic management, and the competitiveness of UAV logistics is still [...] Read more.
With the rapid development of e-commerce, logistics UAVs (unmanned aerial vehicles) have shown great potential in the field of urban logistics. However, the large-scale operation of logistics UAVs has brought challenges to air traffic management, and the competitiveness of UAV logistics is still weak compared with traditional ground logistics. Therefore, this paper constructs a double-layer route network structure that separates logistics transshipment from terminal delivery. In the delivery layer, a door-to-door distribution mode is adopted, and the transshipment node service location model is constructed, so as to obtain the location of the transshipment node and the service relationship. In the transshipment layer, the index of the route betweenness standard deviation (BSD) is introduced to construct the route network planning model. In order to solve the above model, a double-layer algorithm was designed. In the upper layer, the multi-objective simulated annealing algorithm (MOSA) is used to solve the transshipment node service location issue, and in the lower layer, the multi-objective non-dominated sorting genetic algorithm II (NSGA-II) is adopted to solve the network planning model. Based on real obstacle data and the demand situation, the double-layer network was constructed through simulation experiments. To verify the network rationality, actual flights were carried out on some routes, and it was found that the gap between the UAV’s autonomous flight route time and the theoretical calculations was relatively small. The simulation results show that compared with the single-layer network, the total distance with the double-layer network was reduced by 62.5% and the structural intersection was reduced by 96.9%. Compared with the minimum spanning tree (MST) algorithm, the total task flight distance obtained with the NSGA-II was reduced by 42.4%. The BSD factors can mitigate potential congestion risks. The route network proposed in this paper can effectively reduce the number of intersections and make the UAV passing volume more balanced. Full article
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17 pages, 6521 KiB  
Article
Rational Fabrication of Ag2S/g-C3N4 Heterojunction for Photocatalytic Degradation of Rhodamine B Dye Under Natural Solar Radiation
by Ali Alsalme, Ahmed Najm, Nagy N. Mohammed, M. F. Abdel Messih, Ayman Sultan and Mohamed Abdelhay Ahmed
Catalysts 2024, 14(12), 914; https://doi.org/10.3390/catal14120914 - 11 Dec 2024
Cited by 1 | Viewed by 1410
Abstract
Near-infrared light-triggered photocatalytic water treatment has attracted significant attention in recent years. In this novel research, rational sonochemical fabrication of Ag2S/g-C3N4 nanocomposites with various compositions of Ag2S (0–25) wt% was carried out to eliminate hazardous rhodamine [...] Read more.
Near-infrared light-triggered photocatalytic water treatment has attracted significant attention in recent years. In this novel research, rational sonochemical fabrication of Ag2S/g-C3N4 nanocomposites with various compositions of Ag2S (0–25) wt% was carried out to eliminate hazardous rhodamine B dye in a cationic organic pollutant model. g-C3N4 sheets were synthesized via controlled thermal annealing of microcrystalline urea. However, black Ag2S nanoparticles were synthesized through a precipitation-assisted sonochemical route. The chemical interactions between various compositions of Ag2S and g-C3N4 were carried out in an ultrasonic bath with a power of 300 W. XRD, PL, DRS, SEM, HRTEM, mapping, BET, and SAED analysis were used to estimate the crystalline, optical, nanostructure, and textural properties of the solid specimens. The coexistence of the diffraction peaks of g-C3N4 and Ag2S implied the successful production of Ag2S/g-C3N4 heterojunctions. The band gap energy of g-C3N4 was exceptionally reduced from 2.81 to 1.5 eV with the introduction of 25 wt% of Ag2S nanoparticles, implying the strong absorbability of the nanocomposites to natural solar radiation. The PL signal intensity of Ag2S/g-C3N4 was reduced by 40% compared with pristine g-C3N4, implying that Ag2S enhanced the electron–hole transportation and separation. The rate of the photocatalytic degradation of rhodamine B molecules was gradually increased with the introduction of Ag2S on the g-C3N4 surface and reached a maximum for nanocomposites containing 25 wt% Ag2S. The radical trapping experiments demonstrated the principal importance of reactive oxygen species and hot holes in destroying rhodamine B under natural solar radiation. The charge transportation between Ag2S and g-C3N4 semiconductors proceeded through the type I straddling scheme. The enriched photocatalytic activity of Ag2S/g-C3N4 nanocomposites resulted from an exceptional reduction in band gap energy and controlling the electron–hole separation rate with the introduction of Ag2S as an efficient photothermal photocatalyst. The novel as-synthesized nanocomposites are considered a promising photocatalyst for destroying various types of organic pollutants under low-cost sunlight radiation. Full article
(This article belongs to the Section Photocatalysis)
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12 pages, 3778 KiB  
Article
Investigation of Two Novel Heterojunction Photocatalysts with Boosted Hydrogen Evolution Performance
by Kaifeng Zhang, Xudong Wang and Yanjing Su
Nanomaterials 2024, 14(23), 1947; https://doi.org/10.3390/nano14231947 - 4 Dec 2024
Viewed by 996
Abstract
Among the reported photocatalysts, ZnIn2S4 has garnered significant research interest due to its advantageous layered structure and appropriate band gap. However, achieving rational design and effective interfacial regulation in heterojunctions remains challenging. In this study, we designed two novel heterojunctions: [...] Read more.
Among the reported photocatalysts, ZnIn2S4 has garnered significant research interest due to its advantageous layered structure and appropriate band gap. However, achieving rational design and effective interfacial regulation in heterojunctions remains challenging. In this study, we designed two novel heterojunctions: SrTiO3@ZnIn2S4 and SrCrO3@ZnIn2S4. The photocatalytic hydrogen evolution performance of prepared heterojunctions was systematically investigated under different single-wavelength light sources. Without a cocatalyst, the optimized hydrogen evolution efficiency of SrTiO3@ZnIn2S4 and SrCrO3@ZnIn2S4 reached 3.27 and 4.6 mmol g−1. The enhanced photocatalytic performance can be attributed to the formation of a type-II heterojunction, which improves light absorption capabilities and promotes the separation and transfer of photoinduced carriers. This study provides valuable insights into the strategic construction of heterojunctions for photocatalytic water splitting. Full article
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13 pages, 3416 KiB  
Article
Facile Fabrication of TiO2 Quantum Dots-Anchored g-C3N4 Nanosheets as 0D/2D Heterojunction Nanocomposite for Accelerating Solar-Driven Photocatalysis
by Jin-Hyoek Lee, Sang-Yun Jeong, Young-Don Son and Sang-Wha Lee
Nanomaterials 2023, 13(9), 1565; https://doi.org/10.3390/nano13091565 - 6 May 2023
Cited by 9 | Viewed by 2675
Abstract
TiO₂ semiconductors exhibit a low catalytic activity level under visible light because of their large band gap and fast recombination of electron–hole pairs. This paper reports the simple fabrication of a 0D/2D heterojunction photocatalyst by anchoring TiO₂ quantum dots (QDs) on graphite-like C₃N₄ [...] Read more.
TiO₂ semiconductors exhibit a low catalytic activity level under visible light because of their large band gap and fast recombination of electron–hole pairs. This paper reports the simple fabrication of a 0D/2D heterojunction photocatalyst by anchoring TiO₂ quantum dots (QDs) on graphite-like C₃N₄ (g-C₃N₄) nanosheets (NSs); the photocatalyst is denoted as TiO₂ QDs@g-C₃N₄. The nanocomposite was characterized via analytical instruments, such as powder X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, t orange (MO) under solar light were compared. The TiO₂ QDs@g-C₃N₄ photocatalyst exhibited 95.57% MO degradation efficiency and ~3.3-fold and 5.7-fold higher activity level than those of TiO₂ QDs and g-C₃N₄ NSs, respectively. Zero-dimensional/two-dimensional heterojunction formation with a staggered electronic structure leads to the efficient separation of photogenerated charge carriers via a Z-scheme pathway, which significantly accelerates photocatalysis under solar light. This study provides a facile synthetic method for the rational design of 0D/2D heterojunction nanocomposites with enhanced solar-driven catalytic activity. Full article
(This article belongs to the Special Issue Nanocatalysts for Environmental Remediation)
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15 pages, 3879 KiB  
Article
Energy Costs Reduction for Dispersion Using a Jet-Slot Type Milk Homogenizer
by Kyrylo Samoichuk, Alexandr Kovalyov, Natalia Fuchadzhy, Taras Hutsol, Michał Jurczyk, Tadeusz Pająk, Marian Banaś, Olena Bezaltychna and Alona Shevtsova
Energies 2023, 16(5), 2211; https://doi.org/10.3390/en16052211 - 24 Feb 2023
Cited by 9 | Viewed by 2242
Abstract
The priority task of the milk processing industry is in reducing the specific energy consumption of milk fat dispersion while simultaneously ensuring a high dispersion of milk emulsion. One of the possible ways to solve this problem is by developing and implementing a [...] Read more.
The priority task of the milk processing industry is in reducing the specific energy consumption of milk fat dispersion while simultaneously ensuring a high dispersion of milk emulsion. One of the possible ways to solve this problem is by developing and implementing a little-studied jet milk homogenizer of the slot type. In it, homogenization occurs by implementing the method of the separate feeding of cream, which allows creating the maximum difference between the speeds of skim milk and cream, which is a necessary condition for effective dispersion. Analytical dependences have been found that relate power and specific energy consumption to the performance of a milk homogenizer with the separate cream supply, the diameter of the annular gap, the fat content of normalized milk and cream, and the cream supply speed. The rational value of the fat content of the cream used for homogenization is analytically substantiated; in order to reduce the specific energy consumption of the process, their fat content should be higher than 20%. The most significant increase in the energy costs of dispersion is observed when processing milk with a fat content of less than 3–4%, while the use of cream with a fat content of less than 20% leads to a multiple increase in the energy costs of the process. The research results indicate the hyperbolic nature of the dependence of the homogenizer power on its productivity. Supplying the cream through an annular gap of small diameter allows reducing the main component of dispersion energy costs by eight times. The obtained data indicate the existence of a deviation within 5–10% of the experimental power values from the analytical ones, which is explained by the influence of the efficiency of pumps, drives, and losses in the connecting fittings. Full article
(This article belongs to the Collection Energy Efficiency and Environmental Issues)
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17 pages, 4399 KiB  
Article
A Novel Hybrid Excitation Doubly Salient Generator with Separated Windings by PM Inserted in Stator Slot for HEVs
by Mengyao Wang, Baoquan Kou, Lu Zhang, Yuansheng Zhao and Jian Xu
Energies 2022, 15(21), 7968; https://doi.org/10.3390/en15217968 - 27 Oct 2022
Cited by 3 | Viewed by 2184
Abstract
Aiming to design a generator with high reliability, high efficiency, and especially a constant output voltage over a wide speed range for hybrid electric vehicles (HEVs), this paper proposes a novel topology of a hybrid excitation doubly salient generator with separate windings (HEDSGSW). [...] Read more.
Aiming to design a generator with high reliability, high efficiency, and especially a constant output voltage over a wide speed range for hybrid electric vehicles (HEVs), this paper proposes a novel topology of a hybrid excitation doubly salient generator with separate windings (HEDSGSW). The topology herein utilizes a hybrid excitation type of PMs and DC windings to generate parallel magnetic circuits. In addition, PMs are embedded in the magnetic bridge to insulate the excitation windings with armature windings. This design can achieve compactness, efficiency, and especially constant output capability over a wide speed range. The geometry and flux regulation principles, including magnetic flux circuits, are elaborated. After comparing three power generation modes, the most suitable mode, namely, the doubly salient generation 2 (DSG2) mode, is confirmed to ensure a stable voltage output performance. Then, considering the non-uniformity effect of the stator and rotor slots, the no-load back electromotive force (EMF) expressions are derived based on the EMF to air-gap relative permeance method. Furthermore, a 1 kW HEDSGSW FEA model, with an output voltage of 42 V and a rated speed of 6000 rpm, is built to demonstrate the effectiveness of the proposed method. Finally, the operating properties of the HEDSGSW, such as no-load characteristics and adjustment characteristics, are analyzed to further verify the rationality of its magnetic flux circuit and the flexibility of the excitation regulation capability. Full article
(This article belongs to the Special Issue Advanced Permanent-Magnet Machines for Electric Vehicles)
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21 pages, 1708 KiB  
Article
A First Step towards Zero Nuclear Waste—Advanced Strategic Thinking in Light of iMAGINE
by Bruno Merk, Anna Detkina, Dzianis Litskevich, Maulik Patel, Omid Noori-kalkhoran, Gregory Cartland-Glover, Olga Efremova, Mark Bankhead and Claude Degueldre
Energies 2022, 15(19), 7209; https://doi.org/10.3390/en15197209 - 30 Sep 2022
Cited by 6 | Viewed by 2625
Abstract
Traditionally, there has been a gap between reactor operation and the consideration of nuclear waste in the final disposal. Fuel is produced, and fuel must be disposed. In the view of the reactor operator, fuel has to be cleaned in the reprocessing, and [...] Read more.
Traditionally, there has been a gap between reactor operation and the consideration of nuclear waste in the final disposal. Fuel is produced, and fuel must be disposed. In the view of the reactor operator, fuel has to be cleaned in the reprocessing, and new solid fuel has to be produced in the view of the chemist. iMAGINE is designed to overcome this separation through a breakthrough development applying an optimized, integrative approach from cradle to grave of nuclear energy production as a first step to come as close as possible to the vision of zero waste nuclear power. It is described here for the first time in three steps: reactor, fuel cycle, and waste, providing the rationality behind each of the choices made to come to the overall solution to open the discussion and thinking process on what could be achieved by a very innovative approach to integrated nuclear energy production. The opportunities regarding the handling of the remaining waste are discussed with a view on the expectation of the final disposal community, the study “Nuclear waste from small modular reactors”, and the IAEA report “waste from innovative types of reactors and fuel cycles—a preliminary study”. The aim of this work is not to find answers to each of the raised points, but to identify potential approaches and promising ways to go, as well as to stimulate a discussion among experts. In the best case, this could lead to a change of track for nuclear power to become even more sustainable and an important, trusted technology to help solve the net-zero challenge. Full article
(This article belongs to the Section B4: Nuclear Energy)
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11 pages, 1897 KiB  
Article
Synthesis of Silver Nanoparticles-Modified Graphitic Carbon Nitride Nanosheets for Highly Efficient Photocatalytic Hydrogen Peroxide Evolution
by Jixiang Hou, Xu Zhang, Kaiwen Wang, Peijie Ma, Hanwen Hu, Xiyuan Zhou and Kun Zheng
Molecules 2022, 27(17), 5535; https://doi.org/10.3390/molecules27175535 - 28 Aug 2022
Cited by 8 | Viewed by 2771
Abstract
As a promising metal-free photocatalyst, graphitic carbon nitride (g-C3N4) is still limited by insufficient visible light absorption and rapid recombination of photogenerated carriers, resulting in low photocatalytic activity. Here, we adjusted the microstructure of the pristine bulk-g-C3N [...] Read more.
As a promising metal-free photocatalyst, graphitic carbon nitride (g-C3N4) is still limited by insufficient visible light absorption and rapid recombination of photogenerated carriers, resulting in low photocatalytic activity. Here, we adjusted the microstructure of the pristine bulk-g-C3N4 (PCN) and further loaded silver (Ag) nanoparticles. Abundant Ag nanoparticles were grown on the thin-layer g-C3N4 nanosheets (CNNS), and the Ag nanoparticles decorated g-C3N4 nanosheets (Ag@CNNS) were successfully synthesized. The thin-layer nanosheet-like structure was not only beneficial for the loading of Ag nanoparticles but also for the adsorption and activation of reactants via exposing more active sites. Moreover, the surface plasmon resonance (SPR) effect induced by Ag nanoparticles enhanced the absorption of visible light by narrowing the band gap of the substrate. Meanwhile, the composite band structure effectively promoted the separation and transfer of carriers. Benefiting from these merits, the Ag@CNNS reached a superior hydrogen peroxide (H2O2) yield of 120.53 μmol/g/h under visible light irradiation in pure water (about 8.0 times higher than that of PCN), significantly surpassing most previous reports. The design method of manipulating the microstructure of the catalyst combined with the modification of metal nanoparticles provides a new idea for the rational development and application of efficient photocatalysts. Full article
(This article belongs to the Special Issue Advanced Energy Storage Materials and Their Applications)
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25 pages, 3532 KiB  
Review
Amorphous Solid Dispersions: Role of the Polymer and Its Importance in Physical Stability and In Vitro Performance
by Qin Shi, Haibiao Chen, Yanan Wang, Ruoxun Wang, Jia Xu and Chen Zhang
Pharmaceutics 2022, 14(8), 1747; https://doi.org/10.3390/pharmaceutics14081747 - 22 Aug 2022
Cited by 45 | Viewed by 6276
Abstract
Amorphous solid dispersions stabilized by one or more polymer(s) have been widely used for delivering amorphous drugs with poor water solubilities, and they have gained great market success. Polymer selection is important for preparing robust amorphous solid dispersions, and considerations should be given [...] Read more.
Amorphous solid dispersions stabilized by one or more polymer(s) have been widely used for delivering amorphous drugs with poor water solubilities, and they have gained great market success. Polymer selection is important for preparing robust amorphous solid dispersions, and considerations should be given as to how the critical attributes of a polymer can enhance the physical stability, and the in vitro and in vivo performances of a drug. This article provides a comprehensive overview for recent developments in the understanding the role of polymers in amorphous solid dispersions from the aspects of nucleation, crystal growth, overall crystallization, miscibility, phase separation, dissolution, and supersaturation. The critical properties of polymers affecting the physical stability and the in vitro performance of amorphous solid dispersions are also highlighted. Moreover, a perspective regarding the current research gaps and novel research directions for better understanding the role of the polymer is provided. This review will provide guidance for the rational design of polymer-based amorphous pharmaceutical solids with desired physicochemical properties from the perspective of physical stability and in vitro performance. Full article
(This article belongs to the Special Issue Feature Papers in Physical Pharmacy and Formulation)
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26 pages, 12392 KiB  
Article
Discrete Element Modeling of Instability Mechanisms of Unbound Permeable Aggregate Base Materials in Triaxial Compression
by Yuanjie Xiao, Xiaoming Wang, Qunding Yu, Juanjuan Ren, Wenjun Hua, Ralina Mustafina, Fuguang Zhang, Huaiping Feng and Tongwen Zhang
Materials 2022, 15(8), 2716; https://doi.org/10.3390/ma15082716 - 7 Apr 2022
Cited by 7 | Viewed by 2281
Abstract
Unbound permeable aggregate base (UPAB) materials with strong load-transmitting skeleton yet adequate inter-connected pores are desired for use in the sponge-city initiative. However, the micro-scale fabric evolution and instability mechanism of macroscopic strength behavior of such UPAB materials still remain unclear. In this [...] Read more.
Unbound permeable aggregate base (UPAB) materials with strong load-transmitting skeleton yet adequate inter-connected pores are desired for use in the sponge-city initiative. However, the micro-scale fabric evolution and instability mechanism of macroscopic strength behavior of such UPAB materials still remain unclear. In this study, virtual monotonic triaxial compression tests were conducted by using the discrete element method (DEM) modeling approach on specimens with different gradations quantified by the parameter of gravel-to-sand ratio (G/S). The realistic aggregate particle shape and inter-particle contact behavior were properly considered in the DEM model. The micromechanical mechanisms of the shearing failure of such UPAB materials and their evolution characteristics with G/S values were disclosed from contact force chains, microstructures, and particle motion. It was found that the proportion of rotating particles in the specimens decreased and the proportion of relative sliding between particles increased as the content of fine particles decreased. The plastic yielding of the specimens originated from the failure of contact force chains and the occurrence of the relative motion between particles, while the final instability was manifested by the large-scale relative motion among particles along the failure plane (i.e., changes in the internal particle topology). By comparing the macroscopic strength, microstructure evolution, and particle motion characteristics of the specimens with different G/S values, it was found that the specimens with G/S value of 1.8 performed the best, and that the G/S value of 1.8 could be regarded as the threshold for separating floating dense and skeletal gap type packing structures. The variation of Euler angles of rotating particles was significantly reduced in the particle size range of 4.75 mm to 9.50 mm, indicating that this size range separates most of the particles from rolling and sliding. Since particle rolling and sliding behavior are directly related to shear strength, this validates the rationality of the parameter G/S for controlling and optimizing gradations from the perspective of particle movement. The findings could provide theoretical basis and technical guidance for the effective design and efficient utilization of UPAB materials. Full article
(This article belongs to the Special Issue Materials, Structure, and Modeling for Smart and Resilient Roads)
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21 pages, 970 KiB  
Article
Agricultural Potential of the EU Countries: How Far Are They from the USA?
by Karolina Pawlak, Luboš Smutka and Pavel Kotyza
Agriculture 2021, 11(4), 282; https://doi.org/10.3390/agriculture11040282 - 25 Mar 2021
Cited by 50 | Viewed by 6370
Abstract
Although the EU and the USA are the largest players in the global agricultural market, there are only a few up-to-date comparative studies concerning their agricultural potential and performance. No comprehensive study covering all individual EU member states in relation to the USA [...] Read more.
Although the EU and the USA are the largest players in the global agricultural market, there are only a few up-to-date comparative studies concerning their agricultural potential and performance. No comprehensive study covering all individual EU member states in relation to the USA has been provided so far. Considering that in the light of the lasting impasse in the negotiations on both international and transatlantic trade liberalization, differences in the production structures seem to be a decisive factor affecting competitiveness of the EU and the US agriculture, the paper attempts to identify the gap in the agricultural potential between individual EU countries and the USA and determine which EU countries are able to face the competitive pressure exerted by the US agricultural producers. Ward’s agglomerative hierarchical clustering method with the Euclidean distance was used to separate the most and the least competitive countries depending on their agricultural potential. Based on the conducted analyses it may be stated that the US agriculture is characterized by more rational ratios between production factors, resulting in their higher efficiency compared to the EU. The conducted typological analysis showed that thanks to the high standard of capital assets per employee leading to high labor productivity, only such countries as Germany, the Netherlands, France, Denmark, and Belgium may be considered as capable of meeting the competitive pressure exerted by the US agriculture with its greater degree of concentration and benefits from proper proportions between the production factors. A much more difficult competitive situation is observed in the EU countries of Central and Eastern Europe as well as the Mediterranean region, specializing in land- and labor-intensive production, in which the rational utilization of the production potential is limited by the structural deficit, resulting from the fragmented agrarian structure and manifested in the low level of land and capital assets assigned to labor actively involved in the production process. Full article
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20 pages, 4515 KiB  
Article
Development of a Refined Analysis Method for Earthquake-Induced Pounding between Adjacent RC Frame Structures
by Yongqiang Yang and Shuang Li
Sustainability 2019, 11(18), 4928; https://doi.org/10.3390/su11184928 - 9 Sep 2019
Cited by 8 | Viewed by 2698
Abstract
Pounding of two adjacent structures is one of the factors that cause damage and hinder sustainable use of reinforced concrete (RC) frame structures under strong ground motion excitations. This study developed a pounding analysis method with a refined beam-column element in order to [...] Read more.
Pounding of two adjacent structures is one of the factors that cause damage and hinder sustainable use of reinforced concrete (RC) frame structures under strong ground motion excitations. This study developed a pounding analysis method with a refined beam-column element in order to solve the pounding problem between two RC frame structures. The analysis method combines the fiber beam-column element model with the element sections discretized into concrete and longitudinal rebar fibers, the Hertz-damp contact element model to describe the pounding between beam-column elements, and the method to integrate the pounding force into the system dynamic equilibrium equation. The pounding can be considered either at the level between the story slab to slab or at the level between story slab to mid-column. The application of the proposed method in pounding analyses to provide a rational seismic separation gap between two adjacent RC frame structures is finally conducted to increase their safety and sustainability under strong earthquakes. Full article
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29 pages, 2222 KiB  
Review
Photocatalytic Water Splitting—The Untamed Dream: A Review of Recent Advances
by Tahereh Jafari, Ehsan Moharreri, Alireza Shirazi Amin, Ran Miao, Wenqiao Song and Steven L. Suib
Molecules 2016, 21(7), 900; https://doi.org/10.3390/molecules21070900 - 9 Jul 2016
Cited by 522 | Viewed by 35715
Abstract
Photocatalytic water splitting using sunlight is a promising technology capable of providing high energy yield without pollutant byproducts. Herein, we review various aspects of this technology including chemical reactions, physiochemical conditions and photocatalyst types such as metal oxides, sulfides, nitrides, nanocomposites, and doped [...] Read more.
Photocatalytic water splitting using sunlight is a promising technology capable of providing high energy yield without pollutant byproducts. Herein, we review various aspects of this technology including chemical reactions, physiochemical conditions and photocatalyst types such as metal oxides, sulfides, nitrides, nanocomposites, and doped materials followed by recent advances in computational modeling of photoactive materials. As the best-known catalyst for photocatalytic hydrogen and oxygen evolution, TiO2 is discussed in a separate section, along with its challenges such as the wide band gap, large overpotential for hydrogen evolution, and rapid recombination of produced electron-hole pairs. Various approaches are addressed to overcome these shortcomings, such as doping with different elements, heterojunction catalysts, noble metal deposition, and surface modification. Development of a photocatalytic corrosion resistant, visible light absorbing, defect-tuned material with small particle size is the key to complete the sunlight to hydrogen cycle efficiently. Computational studies have opened new avenues to understand and predict the electronic density of states and band structure of advanced materials and could pave the way for the rational design of efficient photocatalysts for water splitting. Future directions are focused on developing innovative junction architectures, novel synthesis methods and optimizing the existing active materials to enhance charge transfer, visible light absorption, reducing the gas evolution overpotential and maintaining chemical and physical stability. Full article
(This article belongs to the Special Issue Photocatalytic Water Splitting—the Untamed Dream)
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