Mode Of Deposition Research Articles

Prediction of impulse waves generated by the potential failure of large deposits in the Rumei Reservoir, Lancang River, China

The impulse wave generated by the reservoir landslide seriously endangers the surrounding safety. In this paper, the failure mode of a large deposit in Rumei Reservoir, China was first explored by centrifuge test. Thereafter, a physical model based on Froude similarity (scale 1:200) and a numerical model based on fluid‒solid coupling were constructed. The failure motion process and the generated impulse waves of the deposits at high (2895 m) and low (2750 m) water levels are studied in detail. The results of the two models are similar. The velocity and wave height of the deposits at the 2750 m water level are greater than those at the 2895 m water level. The maximum wave heights generated in the river under both conditions exceed 46 m and 22 m, respectively, and the maximum run-ups formed on the opposite bank are 71 m and 30 m, respectively. This also suggests that landslides in the near field area are dangerous. Waves at both water levels will not overtop the dam, but attention should be given to the effect of the first wave at the 2895 m water level on the dynamic water pressure in the key area of the dam.

Evaporitic–lacustrine mudstone laminites and prodelta mudlobes – continuity and change in the Hartmann's Valley interval, Murray formation, Gale crater, Mars

ABSTRACTThe sedimentary fill of Gale crater on Mars is dominated by lacustrine strata that are the focus of investigations into surface processes, climate change and habitability early in the planet's history. This study focuses on the lower part of the explored portion of the Murray formation on Aeolis Mons (Mount Sharp) in the Pahrump Hills and Hartmann's Valley field areas. At Pahrump Hills, sedimentary features and geochemical attributes of exposed mudstones suggest accumulation in an underfilled lake basin in which lake levels, shorelines and salinities fluctuated greatly at various temporal scales. The immediately superjacent stratigraphic interval, designated by the rover team as the Hartmann's Valley member, has previously been interpreted as an aeolian‐deposited sandstone interval. This fresh examination of all available data, however, suggests that the Hartmann's Valley member is strongly dominated by the same mudstone facies that compose most of the underlying Pahrump Hills member. The one novel facies element encountered in the Hartmann's Valley member are undulose bedded to convex bodies of mudstone that are oriented roughly north–south, suggestive of sediment supply from a northern fluvial source. Mudstones analogous in scale and character to these undulose mudstones occur on Earth in multiple modern and ancient lacustrine successions, and are related to deposition of prodelta mud lobes. The mudstones of the Hartmann's Valley member record a continuation of the underfilled evaporitive lake system proposed previously for the underlying Pahrump Hills member but with somewhat more variable environmental conditions. Hartmann's Valley mudstones contain more abundant matrix CaSO4, suggesting more severe evaporitic conditions, whereas the interbedded undulose bedded mudstones signify intermittent freshening and buildout of mud‐dominated deltas into the lake. The textural similarities between Pahrump Hills and Hartmann's Valley strata suggest that the Gale lacustrine system operated at a stable depositional mode with similar environmental parameters during both stratigraphic intervals.

Simulation of Total Harmonic Distortion of Solid Oxide Fuel Cells for Carbon Deposition Detection

Abstract Identifying the degradation mechanisms at the early stage of operation is important for the long-term operation of solid oxide fuel cells (SOFCs). Compared to conventional methods, total harmonic distortion analysis (THDA) can significantly reduce the test time for identifying performance degradation during SOFC operation. In this study, a one-dimensional transient elementary reaction kinetic model of an SOFC fueled with syngas is developed. The model incorporates the coupling effect of elementary chemical and electrochemical reactions, the electrode microstructure, the charge and mass transport processes, and the detailed evolution reaction of surface adsorbed carbon. A THDA simulation calculation method was developed and applied to determine the failure mode of anode carbon deposition. The amplitude, duration, and harmonic number of the perturbation signal are determined to improve fault detection for THDs. The results show that the use of THD can not only detect carbon accumulation behavior at the early stage of SOFC operation but also distinguish the specific degradation mechanism caused by carbon deposition: the hindered SOFC charge transfer reaction can be detected in the frequency range of 100-4000 Hz, and the hindered gas diffusion process inside the anode can be detected in the frequency range of 0.01-10 Hz.

Enabling 2D Electron Gas with High Room-Temperature Electron Mobility Exceeding 100cm2 Vs-1 at a Perovskite Oxide Interface.

In perovskite oxide heterostructures, bulk functional properties coexist with emergent physical phenomena at epitaxial interfaces. Notably, charge transfer at the interface between two insulating oxide layers can lead to the formation of a 2D electron gas (2DEG) with possible applications in, e.g., high-electron-mobility transistors and ferroelectric field-effect transistors. So far, the realization of oxide 2DEGs is, however, largely limited to the interface between the single-crystal substrate and epitaxial film, preventing their deliberate placement inside a larger device architecture. Additionally, the substrate-limited quality of perovskite oxide interfaces hampers room-temperature (RT) 2DEG performance due to notoriously low electron mobility. In this work, the controlled creation of an interfacial 2DEG at the epitaxial interface between perovskite oxides BaSnO3 and LaInO3 is demonstrated with enhanced RT electron mobility values up to 119 cm2 Vs-1-the highest RT value reported so far for a perovskite oxide 2DEG. Using a combination of state-of-the-art deposition modes during oxide molecular beam epitaxy, this approach opens up another degree of freedom in optimization and in situ control of the interface between two epitaxial oxide layers away from the substrate interface. Thus this approach is expected to apply to the general class of perovskite oxide 2DEG systems and to enable their improved compatibility with novel device concepts and integration across materialsplatforms.

Modulating interfacial Zn2+ deposition mode towards stable Zn anode via bimetallic co-doped coating

Artificial coatings represent the promising means to address the interfacial issues of Zn anode, but it poses a significant challenge to their stability due to the fatigue and resulting cracking of coatings during repeated cycling. Here, a functional coating with the synergistic effect of bimetallic co-doping was developed, which changes the Zn2+ deposition mode to interlayer deposition in coating. The simultaneous doping of Cu2+ and In3+ reduces the pyrrolic N content and enhances the adsorption of Zn2+ in the active sites. Bimetallic co-doping results in an increase in specific surface area and a decrease in pore size, thus providing more active sites. As well as enhanced electrical conductivity, electrons can enter between the coatings, thus promoting redox reactions between the layers. Therefore, it endows surface coating with low polarization and stress buffering simultaneously, which avoids cracking and stripping of coatings during cycling. As a result, the cycle life of CuInZIF-8@Zn||CuInZIF-8@Zn symmetric cell exhibits more than 1200 h at 5 mA cm−2 and 5 mAh cm−2. The CuInZIF-8@Zn anode can match multiple types of cathodes and achieve excellent cycling stability; For instance, it can cycle stably for 3000 cycles when paired with vanadium-based cathode. This work provides a new perspective of artificial coatings towards highly stable Zn anode.

Crystal Step‐Induced Uniform and Rapid Deposition on Zinc Anodes

AbstractAqueous Zn‐ion batteries have emerged as promising candidates for large‐scale energy storage owing to their high safety and low cost. However, dendrite growth and side reactions compromise the stability of the Zn anode in practical applications. Here, a novel Zn anode featuring well‐designed crystal steps along the (002) facets, referred to as Step‐Zn is introduced. The intersections of the (002) and (100) planes in these crystal steps create preferential adsorption sites for Zn2⁺ ions, promoting initial electro‐epitaxial growth of Zn that uniformly covers the crystal steps. This process effectively regulates subsequent Zn deposition, ensuring fast reaction kinetics and smooth morphology without dendrite formation. Consequently, the unique Step‐Zn anode exhibits excellent cycle life over 6000 times at 3 mA cm−2 and low greatly reduced polarization voltage under high areal currents and capacities. Integrated with activated carbon (AC) cathode, the Step‐Zn||AC full cell demonstrates excellent durability over 10 000 cycles at 5 A g−1. This work offers valuable insights into controlling Zn deposition modes by engineering the surface microstructure of Zn anodes with greatly extended cycling stability.

Janus-structured graphene scaffold for bottom-up lithium deposition: A progressive gradient approach

Graphene-based materials have been explored as hosts for Li metal anodes, but their high interfacial activity and short diffusion distances frequently result in dendrite formation on the surface. Herein, we utilize the adjustable conductivity and Li affinity of graphene oxide (GO) to develop a Janus structure comprising a top GO layer and a bottom reduced graphene oxide (rGO) layer. The progressive conductivity and lithiophilicity gradient structure of GO/rGO enables a bottom-up Li deposition mode, rendering an average Coulombic efficiency of 99.1 % over 350 cycles at 1 mA cm−2 and 1 mAh cm−2. Full cells equipped with a LiFePO4 cathode maintain a capacity retention of 85 % after 350 cycles at 1 C. This innovative approach provides fresh insights into the development of graphene-based hosts, offering significant potential for future Li metal battery applications.

Study of Optical, Electrophotographic and Holographic Parameters of As-Se Condensates from the Prehistory of the Original Bulk Materials

The results of a study of the optical, electrophotographic and holographic parameters of As-Se condensates from the prehistory of the original bulk materials are presented. It has been established that the electrophotographic parameters of freshly deposited As40Se60 layers change significantly with temperature; the dependences of the maximum charging potential (U0) and the half-decay time of the potential (τ1/2) of electrophotographic As40Se60 layers in the dark on the processing temperature of the melt of the starting material are shown. The dependence of the half-life of the potential in the dark, as well as the properties of bulk samples, has an extremum in the region of Tsub~500°C. The correlation between the dependences of the properties of bulk samples and the electrophotographic parameters of the layers on Tsub indicates that the structural features of the source material in the deposition mode used affect the structure of the films.

Behavior of Polymer Electrode PEDOT:PSS/Graphene on Flexible Substrate for Wearable Biosensor at Different Loading Modes.

In recent years, flexible and wearable biosensor technologies have gained significant attention due to their potential to revolutionize healthcare monitoring. Among the various components involved in these biosensors, the electrode material plays a crucial role in ensuring accurate and reliable detection. In this regard, polymer electrodes, such as Poly(3,4 ethylenedioxythiophene): poly(styrenesulfonate), combined with graphene (PEDOT:PSS/graphene), have emerged as promising candidates due to their unique mechanical properties and excellent electrical conductivity. Understanding the mechanical behavior of these polymer electrodes on flexible substrates is essential to ensure the stability and durability of wearable biosensors. In this paper, PEDOT:PSS/graphene composite was spray-coated on flexible substrates at different growth conditions to explore the effect of the deposition parameters and mode of mechanical loading (longitudinal or transversal) on the electrical and mechanical behavior of the fabricated samples. It was found that the coating grown at lower temperatures and higher spraying pressure exhibited stable behavior no matter the applied stress type.

Where did it go? A study of DNA transfer in a social setting

The sensitivity of DNA analysis has progressed to the point that trace levels of DNA, originating from only a few cells, can generate informative profiles. This means that virtually any item or surface can be sampled with a reasonable chance of obtaining a DNA profile. As the presence of DNA does not suggest how it was deposited, questions are often raised as to how the DNA came to be at a particular location and the activity that led to its deposition. Therefore, understanding different modes of DNA deposition, reflective of realistic forensic casework situations, is critical for proper evaluation of DNA results in court. This study aimed to follow the movements of DNA to and from individuals and common household surfaces in a residential premises, while socially interacting. This took place over an hour and involved four participants, with known shedder status, designated as visitors (a male and a female) and hosts (a male and a female), who engaged in the activity of playing a board game while being served food. During the study, the participants were instructed to use the toilet on a single occasion to assess the transfer of DNA to new and unused underwear that was provided. All contacts made by the participants in the dining room and kitchen were video recorded to follow the movements of DNA. Samples were collected based on the history of contact, which included hands, fingernails and penile swabs. Direct contacts resulted in detectable transfer (LR > 1) in 87 % (87/100) of the non-intimate samples and clothing. For surfaces touched by multiple participants, DNA from the person who made the last contact was not always detectable. The duration and number of contacts did not significantly affect the detection of the person contacting the item. On the other hand, presence of background DNA and participant’s shedder status appear to play an important role. Further, unknown contributors were detected in the majority of samples. Finally, indirect transfer was observed on a number of occasions including co-habiting partners of guests who were not present at the study location. The results of this study may assist with decision making for exhibit selection or targeting areas for sampling within the home environment. Our findings can also be used in conjunction with previous literature to develop activity-level evaluations in such situations where the source of the DNA is conceded, but the mode of deposition is disputed.

Polycrystalline silicon, a molecular dynamics study: I. Deposition and growth modes

Polycrystalline silicon (poly-Si) significantly expands the properties of the ICT miracle material, silicon (Si). Depending on the grain size and shape and grain boundary structure, the properties of poly-Si exceed what single-crystal (c-Si) and amorphous (a-Si) silicon can offer, especially for radio frequency (RF) applications in microelectronics. Due to its wide range of applications and, on the one hand, its theoretically and technologically challenging microstructure, poly-Si research is the most timely (Ding et al 2020 Mater. Charact. 161 110174; Zhao and Li 2019 Acta Mater. 168 52–62). In this report, we describe how we simulate and analyse the phenomena and mechanisms that control the effect of poly-Si deposition parameters on the structure of the deposited poly-Si films using classical molecular dynamics simulations. The grain shape and size, degree of crystallinity, grain boundary structure and the stress of poly-Si films are determined depending on the growth temperature, temperature distribution in the growing film, deposition flux, flux variation and the energy transferred to the film surface due to the deposition flux. The main results include: (i) the dependence of the crystallinity profile of the deposited poly-Si films on the stress, temperature and the different parameters of the deposition flux, (ii) growth modes at the early stages of the deposition, (iii) interaction and stability of seed crystallites at the early stage of the deposition of poly-Si films and the transition from the isolated crystallite growth to the poly-Si growth, (iv) interplay of the temperature, crystallinity, crystal shape and heath conductivity of different Si phases, (v) four different stages of crystallite growth are described: nucleation, growth, disappearance and retardation.

Lithiophilic V2CTx/MoO3 Hosts with Electronic/Ionic Dual Conductive Gradients for Ultrahigh‐Rate Lithium Metal Anodes

AbstractLithium (Li) metal is considered as a promising anode material for high‐energy batteries; yet, its practical application is hindered by uncontrolled Li dendrite growth, especially at a high rate. Herein, a dual conductive gradient V2CTx/MoO3 (DG‐V2CTx/MoO3) host that integrates electronic/ionic conductive gradients and lithiophilicity is prepared by layer‐by‐layer assembly for dendrite‐free Li anodes. Gradient LiF deriving from different amount of V2CTx endows a good ionic conductive gradient; while, MoO3 is regarded as a spacer to avoid the restacking of V2CTx, increasing space for Li deposition. The dual conductive gradients effectively optimize the current density and Li+ flux distribution at the bottom, achieving fast reduction of Li+ and a “bottom–up” Li deposition mode. Meanwhile, the lithiophilic V2CTx and MoO3 guide the homogeneous Li growth. As a result, the symmetrical half‐cells based on DG‐V2CTx/MoO3@Li anodes conduct 700 h at 5 mAh cm−2 and 20 mA cm−2. The DG‐V2CTx/MoO3@Li||LiFePO4 full‐cells maintain a capacity retention of 85.4% after 1350 cycles at 2 C. Remarkably, the DG‐V2CTx/MoO3@Li||LiNi0.6Co0.2Mn0.2O2 full‐cells can run 150 cycles with 80.6% capacity retention even at harsh conditions. The well‐adjusted materials and structures with both dual conductive gradients and lithiophilic properties will bring inspiration for novel material design of other metal batteries.

Numerical simulation of non-stationary regime of a submerged combustion setup operation

Relevance. The need to evaporate large quantities of brines at potash industry enterprises. Evaporation of brines in surface evaporators is difficult due to the encrustation of heat exchange surfaces by salt deposits. Therefore, such evaporation is most expedient to be carried out in submerged combustion apparatuses, since they do not contain heat-transmitting surfaces. However, in this type of apparatus, malfunctions may occur due to uncontrolled solid phase deposition. At the moment, the dynamics of the solid phase in submerged combustion devices is poorly studied. This study is part of a scientific program aimed at a comprehensive review of the laws of motion of solid particles in submerged combustion apparatuses. Aim. To study the hydrodynamic processes in the submerged combustion setup in the time interval corresponding to the beginning of its operation; describe the patterns of solid phase motion as a function of time. Object. Laboratory setup of submerged combustion. A simplified model of the thermal mode of operation without the subsequent transition of the liquid phase to steam is analyzed. Methods. The study was conducted by numerical experiment. The hybrid finite volume method was used in simulation in combination with the technology of the finite element method. The multiphase system was considered as two coexisting subsystems: gas–liquid and liquid–solid. Results. The paper considers the final time interval of the setup operation. It is found that during the time under consideration, a stationary mode of solid particle deposition is achieved. The authors have detected liquid flow velocity oscillations, leading to fluctuations in the mass flow rate of solid particles at the bottom of the setup. It was found that the velocity at the tip of the flue gas jet escaping from the burner nozzle, as well as the pressure at the nozzle section, have a similar form of oscillation. The authors substantiated the hypothesis about the determining influence of the instability of the jet movement of flue gases on the oscillatory behavior of the entire hydrodynamic system.

Physics of microscale freeform 3D printing of ice

Ice is emerging as a promising sacrificial material in the rapidly expanding area of advanced manufacturing for creating precise 3D internal geometries. Freeform 3D printing of ice (3D-ICE) can produce microscale ice structures with smooth walls, hierarchical transitions, and curved and overhang features. However, controlling 3D-ICE is challenging due to an incomplete understanding of its complex physics involving heat transfer, fluid dynamics, and phase changes. This work aims to advance our understanding of 3D-ICE physics by combining numerical modeling and experimentation. We developed a 2D thermo-fluidic model to analyze the transition from layered to continuous printing and a 3D thermo-fluidic model for the oblique deposition, which enables curved and overhang geometries. Experiments are conducted and compared with model simulations. We found that high droplet deposition rates enable the continuous deposition mode with a sustained liquid cap on top of the ice, facilitating smooth geometries. The diameter of ice structures is controlled by the droplet deposition frequency. Oblique deposition causes unidirectional spillover of the liquid cap and asymmetric heat transfer at the freeze front, rotating the freeze front. These results provide valuable insights for reproducible 3D-ICE printing that could be applied across various fields, including tissue engineering, microfluidics, and soft robotics.

Diverse sources and aging change the mixing state and ice nucleation properties of aerosol particles over the western Pacific and Southern Ocean

Abstract. Atmospheric particles can impact cloud formation and play a critical role in regulating cloud properties. However, particle characteristics at the single-particle level and their ability to act as ice-nucleating particles (INPs) over the marine atmosphere are poorly understood. In this study, we present micro-spectroscopic characterizations and ice nucleation properties of particles collected during a cruise from South Korea to Antarctica in 2019. Most of the samples were dominated by fresh sea salt, aged sea salt, and sea salt mixed with sulfate particles, with total number percentages ranging from 48 % to 99 % over the western Pacific and the Southern Ocean. The mixing-state index of the particle population ranged from 50 % to 95 % over the Northern Hemisphere and Southern Hemisphere. Multiphase processes on sea salt particles resulted in chlorine deficiency. This selective aging process made the marine particle population more externally mixed. Ice nucleation onset conditions primarily for the deposition mode were measured and the investigated particles showed diverse ice nucleation abilities. The fresh sea salt particles with organic coatings exhibited the highest ice nucleation ability at a relative humidity with respect to ice as low as 121 %. The sea salt mixed sulfate particle was enriched in INPs by a factor of 1.9. Aging processes affected both the mixing state of the particles and their ice nucleation abilities. Our analysis shows that assuming an internally mixed particle population in the marine atmosphere can lead to errors of several orders of magnitude in predicting ice nucleation rates.

Enhancing Internal and External Stability of Perovskite Solar Cells Through Polystyrene Modification of the Perovskite and Rapid Open‐Air Deposition of ZnO/AlOx Nanolaminate Encapsulation

In this study, the internal and external stabilities of a p–i–n methylammonium lead iodide perovskite solar cell (PSC) are improved. Polystyrene (PS) is introduced into the perovskite layer to form a cross‐linked polymer–perovskite network, which enhances the nucleation and growth of the perovskite grains. Moreover, for the first time, 60 nm thick ZnO/AlOx nanolaminate (NL) thin‐film encapsulation (TFE) is deposited directly on the PSC using an atmospheric‐pressure (AP) spatial atomic layer deposition system operated in AP spatial chemical vapor deposition (AP–SCVD) mode. The rapid nature of AP–SCVD enables encapsulation of the PSCs in open air at 130 °C without damaging the perovskite. The PS additive improves the performance and internal stability of the PSCs by reducing ion migration. Both the PS additive and the ZnO/AlOx NL TFEs improve the external stability under standard test conditions (dark, 65 °C, 85% relative humidity [RH]) by preventing water ingress. The number and thickness of the ZnO/AlOx NL layers are optimized, resulting in a water–vapor transmission rate as low as 5.1 × 10−5 g m−2 day−1 at 65 °C and 85% RH. A 14‐fold increase in PSC lifetime is demonstrated; notably, this is achieved using PS, a commodity‐scale polymer, and AP–SCVD, a scalable, open‐air encapsulation method.

Structure of the Hir histone chaperone complex

The evolutionarily conserved HIRA/Hir histone chaperone complex and ASF1a/Asf1 co-chaperone cooperate to deposit histone (H3/H4)2 tetramers on DNA for replication-independent chromatin assembly. The molecular architecture of the HIRA/Hir complex and its mode of histone deposition have remained unknown. Here, we report the cryo-EM structure of the S.cerevisiae Hir complex with Asf1/H3/H4 at 2.9-6.8Å resolution. We find that the Hir complex forms an arc-shaped dimer with a Hir1/Hir2/Hir3/Hpc2 stoichiometry of 2/4/2/4. The core of the complex containing two Hir1/Hir2/Hir2 trimers and N-terminal segments of Hir3 forms a central cavity containing two copies of Hpc2, with one engaged by Asf1/H3/H4, in a suitable position to accommodate a histone (H3/H4)2 tetramer, while the C-terminal segments of Hir3 harbor nucleic acid binding activity to wrap DNA around the Hpc2-assisted histone tetramer. The structure suggests a model for how the Hir/Asf1 complex promotes the formation of histone tetramers for their subsequent deposition onto DNA.

OPTIMIZATION OF THE MODE OF DEPOSITION OF ASEPTIC CULTURES IN VITRO OF A RARE AND ENDEMIC SPECIES ALLIUM IVASCZENKOAE

Optimization of the method of medium-term storage of the rare and endangered plant species Allium ivasczenkoae under in vitro conditions using modern approaches of biotechnology is an urgent task. Aseptic microplants Allium ivasczenkoae were used as starting material. The cultivation of microplants was carried out on nutrient media supplemented in various combinations with an increased concentration of sucrose, mannitol, chlorocholine chloride, ABA and BAP at various temperature and light conditions of deposition. The survival dynamics of A. ivasczenkoae varied depending on cultivation regimes. After 9 months of deposition, the survival of test-tube plants in mode 1 (control) was 20%, mode 2 - 60-80%, mode 3 - 30-50%. Under experimental conditions, the best results were obtained by depositing aseptic cultures for 9 months at a low positive temperature and low light intensity (mode 2) on nutrient media with the addition of CCC 120 mg/l and a sucrose concentration of 60 g/l and (B-1) and MS medium containing 0.5 mg/l BAP and 3 g/l mannitol (MSВМ). This mode of deposition made it possible to lengthen the period between transplants, as well as to maintain the viability of A. ivasczenkoae microplants from 60 to 80%. The data obtained make it possible to optimize the mode of medium-term storage of Allium ivasczenkoae under in vitro conditions for the mass production of rare species of bulbous plants in order to restore, reproduce and preserve the number of valuable gene pool and natural populations, create gene banks in vitro, reintroduce and green building.

Suppression of coffee rings by controllable nanoparticle enrichment through superhydrophobicity-enabled dynamic evaporation

Coffee rings formed by evaporation of analyte-containing droplets are widely observed in micropatterning, bio-arrays, and trace detection. The coffee-ring effect caused by contact line pinning significantly affects the detection uniformity and sensitivity. Here, we propose a simple and operable method to effectively suppress coffee rings through controllable nanoparticles aggregation by superhydrophobicity-enabled dynamic evaporation. The gold nanoparticles (AuNPs) deposition footprint formed after dynamic evaporation on an integrated superhydrophobic surface was reduced by ∼3 orders of magnitude compared to that of non-interventional evaporation. Detailed experiments, numerical simulations, and theoretical studies have revealed that substrate wettability, temperature and droplet motion behaviors play significant roles in suppressing coffee-ring effect. More critically, based on the force mechanism of AuNPs at the interface/contact line, universal mathematical models and regime maps were established to classify the different deposition modes for AuNPs under different evaporation conditions by introducing dimensionless parameter G, revealing the enrichment mechanism of AuNPs in droplets under superhydrophobicity-enabled dynamic evaporation. The accuracy of the theoretical model and enrichment mechanism was demonstrated through the single-molecule detection of rhodamine 6G with excellent sensitivity (10–17 M, enhancement factor ∼1013) and perfect uniformity (relative standard deviation ∼5.57 %), which provides a valuable guide for research and applications of nanoparticle aggregation.

Incorporating plastic waste fibres for sustainable sandy soil

The increase in urbanization has led governments to build on sites with certain geotechnical ‎hazards, such as liquefaction, ‎low bearing capacity, etc. In recent decades, as governments ‎have focused their efforts on the environmental and ‎economic aspects, researchers have ‎emphasized the need to use suitable alternative materials for the best design features, also the issue of plastic pollution is a significant global problem that requires urgent attention, current initiatives focus on the use of technical solutions to integrate non-biodegradable plastics into ‎the construction of buildings and road pavement.‎ ‎In this ‎paper, a series of direct shear tests were performed to evaluate the benefits of plastic wastes, ‎such as polypropylene ‎‎(PP) pots, and the engineering properties of sand reinforced with such ‎materials. To highlight the contribution of the ‎reinforcement to the shear strength, the ‎tests were carried out on sand reinforced with variable fibre contents (0.2, 0.4, 0.6, ‎and 0.8%) ‎for loose-density sand and medium-density sand. ‎ The experimental results showed that the increase in shear ‎strength is relatively more significant for specimens prepared with dry deposition mode as compared to those prepared ‎with wet deposition mode and it is increased with the fibre content. The inclusion of randomly distributed fibres has a significant effect on the shear strength and dilatation of sandy soils. Furthermore, the recycling fibre used in this study ‎shows a better performance in terms of shear strength. In conclusion, the use of plastic waste as ‎reinforcement would lead ‎to at least two solutions: soil reinforcement and reducing the ‎environmental impact of waste.