Search Results (92)

Droplet microarrays are increasingly used for miniaturized, high-throughput biochemical assays, yet their fabrication commonly relies on complex lithographic processes, custom masks, or specialized coatings. Here we present a simple method for generating hydrophilic arrays on hydrophobic plastic substrates by combining ultrasonic atomization with off-the-shelf perforated masks. A fine mist of poly(vinyl alcohol) (PVA) solution is directed through commercial diamond sieves onto polypropylene (PP) sheets and polystyrene (PS) sheets, forming hydrophilic spots surrounded by the native hydrophobic background. Static contact angle measurements confirm a strong local contrast in wettability (from 100.85 ± 0.91° on untreated PP to 39.96 ± 0.71° on patterned spots, from 95.68 ± 3.61° on untreated PS to 52.00 ± 0.85° on patterned spots), while Image analysis shows droplet CVs of 6–8% in aqueous dye solutions for 1.2–2.0 mm masks; in complex media (LB), droplet uniformity decreases. By mounting the moving mask on a motorized stage, we generate one-dimensional reagent gradients simply by controlling the moving mask motion during atomization. We further demonstrate biological compatibility by culturing Escherichia coli in LB droplets containing resazurin, and by performing localized antibiotic screening using a moving mask-guided streptomycin gradient. The resulting droplet-wise viability data yield an on-chip dose–response curve with an IC₅₀ of 5.1 µg · mL⁻¹ (95% CI: 4.5–5.6 µg·mL⁻¹), obtained from a single array. Covering droplets with Electronic Fluorinated Fluid maintains volumes within 5% of their initial value over 24 h. Compared with conventional droplet microarray fabrication, the proposed method eliminates custom mask production and cleanroom steps, is compatible with standard plastic labware, and intrinsically supports spatial gradients. These attributes make masked ultrasonic atomization a practical platform for high-throughput microfluidic assays, especially in resource-limited settings. Full article

Liepāja Lake, a Natura 2000 protected area and one of the largest coastal freshwater bodies in Latvia, has been historically influenced by urbanization, diffuse agricultural inputs, and legacy contamination from metallurgy and ship-repair industries. Comprehensive, spatially explicit data on its sediment and water chemistry were previously lacking. The dataset used in this study provides an openly accessible record of major and trace element concentrations in surface sediments and surface waters collected during the 2024 field campaign. Sampling sites were distributed across northern, central, and southern zones to capture gradients in anthropogenic pressure and natural variability. Water samples were filtered and acidified following ISO 15587-2:2002, while sediments were homogenized, sieved, and digested following EPA 3051a. Both matrices were analyzed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS, Agilent 8900 ICP-QQQ) with multi-element calibration traceable to NIST standards. The dataset comprises 31 analytes (Li–Bi) with paired standard deviation values, reported in mg kg^–1 (sediments) and µg L^–1 (water). Rigorous validation included certified reference materials, duplicates, blanks, and statistical outlier screening. The resulting data form a reliable geochemical baseline for assessing pollution sources, quantifying spatial heterogeneity, and supporting future monitoring, modeling, and restoration efforts in climate-sensitive Baltic coastal lakes. Full article

The article presents the results of research and development work conducted as part of the H2GEO project, aimed at creating a comprehensive technology for the processing of post-mining coal waste heaps. The core of the solution is a mobile density separation system based on a pulsating jig, enabling effective recovery of carbonaceous and mineral fractions. Laboratory experiments assessed the impact of key process parameters—such as sieve slot size, pulsation frequency, and enrichment time—on the efficiency and accuracy of separation for different grain size classes. The most favorable results were obtained using a 2.5 mm screen, a pulsation frequency of 60 min⁻¹, and extended enrichment time, which ensured high-quality separation and low ash content in the carbon-bearing product. The findings supported the design of a new industrial separator (jig) equipped with advanced control systems, facilitating the production of homogeneous fractions suitable for further processing into hydrogen, geopolymers, and construction materials. The proposed solution aligns with circular economy principles, promoting waste reuse, environmental hazard mitigation, and the revitalization of degraded post-industrial areas. Full article

The paper describes an installation and procedure for evaluating the velocity profile for the airflow produced by the fan of the cleaning unit of a New Holland wheat combine harvester. The velocity profile is based on measurements taken at 52 points spread over the entire surface of the top and bottom sieves, for different speeds of the fan, different positions of the wind boards and different opening positions of the sieves. The experimental data obtained were graphically represented using the Radial Basis Function (RBF) interpolation model and highlighted that the airflow generated by the fan at the upper screen level, in the longitudinal plane and, especially, in the transverse plane, is distributed unevenly, and depends on the fan rotor speed, the opening of the louvers of the two screens and the arrangement of the two deflectors. The correct adjustment of the cleaning unit and correct evaluation of the air velocity profile over the sieves result in the reduction in grain losses from the upper sieve due to grain flotation, reduction in the content of broken grains in the grain tank due to the reduction in the material flow from the tailing auger as well as reduction in the impurities content of the grain tank due to better separation of the material over the surface of the lower sieve. Full article

To address the issue in high-throughput longitudinal axial-flow grain combine harvester cleaning systems, in which the extended length of the cleaning chamber results in airflow velocity attenuation and makes it difficult to efficiently and rapidly remove light impurities, a front-blowing and rear-suction enhanced cleaning technology and device was developed. Based on the investigation of the movement characteristics of the cleaning airflow within the cleaning chamber, a theoretical model was established to describe the velocity variation of the front-blowing and rear-suction enhanced cleaning airflow. CFD simulation software was employed to conduct a comparative analysis of the airflow field structure before and after improvement, aiming to identify the influence patterns of key structural parameters on the airflow field distribution. An orthogonal experiment with three factors and three levels was conducted on the improved cleaning system, focusing on the suction fan speed, vertical installation height of the suction fan, and horizontal distance between the suction fan and the sieve surface. The influence of each factor on the airflow field was analyzed, and the optimal parameter combination was obtained. When the suction fan speed was 2275 r/min, the vertical installation height was 72.5 mm, the horizontal distance to the sieve surface was 385 mm, and the airflow non-uniformity coefficient at the rear part of the screen surface was 11.17%, with a relative error of 4.39% compared to the optimization result. Finally, bench tests were conducted to verify the accuracy of the simulation results. Compared to that before improvement, the airflow non-uniformity coefficient at the rear part of the screen surface in the cleaning chamber was reduced by 59.43%, significantly improving the uniformity of airflow distribution. These findings provide both theoretical and technical support for improving the cleaning efficiency and operational performance of high-throughput grain combine harvesters. Full article

In this study, CGMCC NO:28566, a strain that can efficiently convert Ethyl 4-chloroacetoacetate(COBE) to (R)-4-chloro-3-hydroxybutyrate((R)-CHBE), was screened by soil-sieving bacteria. In order to improve the transformation effect of the strain, the natural low-eutectic solvent (NADES), which can alter the cell permeability, was utilized for assisted catalysis, and a better catalytic effect was achieved. This study was carried out using a co-culture of strains with NADES and secondary addition of NADES on the basis of co-culture, and 10 NADESs were screened at the same time. The co-catalytic effect of 0.5% (w/v) choline chloride: urea (1:2) (ChCl:U (1:2)) was found to be the most significant, with a yield of (R)-CHBE reaching 89.1%, which was 58.2% higher than that of the control group, with a 99% ee value. Furthermore, the catalytic results demonstrated that the co-culture of the strain with NADES during fermentation yielded superior outcomes to the secondary addition of NADES during the reaction buffer. Furthermore, the catalytic effect of ChCl:U (1:2) was demonstrated to be superior to that of its individual components or single-component blends, due to its distinctive valence bonding advantage. The results indicate that the addition of 0.5% (w/v) ChCl:U (1:2) during the co-culture process has the effect of improving cell permeability to a certain extent, thereby increasing the contact between the substrate and the enzyme during the whole-cell catalytic reactions. Full article

Threshing and cleaning are crucial for efficient harvest procedures that are carried out to separate the grains from the biomass and eliminate any potential contaminants or foreign debris. This study examines the cleaning capabilities of the grain cleaning equipment Kimseed Cleaner MK3, a vibratory sieve and air-screen device, for tiny oilseed crops, particularly kalonji (Nigella sativa) and sesame (Sesamum indicum L.), which are valued for their industrial, medicinal, and nutritional properties. These crops frequently provide post-harvest cleaning issues because of their tiny size and vulnerability to contamination from weed seeds, plant residues, and immature or damaged conditions. In order to determine the ideal operating parameters, 0.5 kg of threshed seed samples with 10% moisture content were utilised in the experiment. A variety of shaker frequencies (0.1–10 Hz) and airflow speeds (0.1–10 m/s) were assessed. A two-stage cleaning method was applied for sesame: the first stage targeted larger contaminants (6.5–7.0 Hz and 1.25–1.5 m/s), while the second stage targeted finer impurities (5.25–5.5 Hz and 1.75–2.0 m/s). With a single-stage procedure (5.5–6.0 Hz and 1.0–1.5 m/s), kalonji was successfully cleaned. The findings demonstrated that sesame attained 98.5% purity at the output rate of 200.6 g/min (12.03 kg/h) while kalonji reached 97.6% seed purity at an output rate of 370.2 g/min (22.2 kg/h). These results demonstrate how important carefully regulated shaker frequency and airflow speed are for improving output quality and cleaning effectiveness. The study shows that the Kimseed MK3 is a suitable low-cost, scalable option for research operations and smallholder farmers, providing better seed quality and processing efficiency for underutilised yet economically valuable oilseed crops. Full article

Tunnel Boring Machine (TBM) excavation materials were recycled by sieving and separating particles into sizes 5–10 mm (coarse aggregates) and below 5 mm (manufactured sand) to explore their potential as aggregates in shotcrete production, with the aim of reducing environmental harm from waste disposal. Mix proportion experiments were conducted to evaluate the mechanical properties—including failure patterns, compressive strength, flexural strength, and deflection—of the shotcrete specimens through cubic axial compression and four-point bending tests; furthermore, rebound tests were conducted on shotcrete mixed with the recycled TBM aggregates in foundation pit engineering. These tests assessed the effects of key parameters (water–binder ratio, sand ratio, fly ash content, synthetic fibers, and liquid alkali-free accelerator) on shotcrete composed of recycled TBM sand and gravel. The results indicated that crushing and grading flaky TBM-excavated rock fragments, and subsequently blending them with pre-screened fine aggregates in a 4:1 ratio, yielded manufactured sand with an optimized particle gradation and controlled stone powder content (18%). Adjusting the water–binder ratio (0.4–0.5), fly ash dosage (mixed with 0–20%), and sand ratio (0.5–0.6) are feasible steps in preparing shotcrete with a compressive strength of 29.1 MPa to 50.4 MPa and slump of 9 cm to 20 cm. Moreover, the rebound rate of the shotcrete reached 11.3% by applying polyoxymethylene (POM) fibers with a 0.15% volume fraction and a liquid-state alkali-free setting accelerator (8% dosage), demonstrating that the implemented approach enables a decrease in the rebound rate of shotcrete. Full article

To conduct DEM simulation research on the collision characteristics between seeds and pressed substrate holes, a discrete element model of mechanically pressed holes in sowing substrates was developed in this study. The geometric DEM models of sowing substrate particles were established based on the sieve test, and the Hertz–Mindlin with JKR contact model was utilized for simulating of the fine, moist, and cohesive substrate particles. The angle of repose measured by the funnel method was served as the target, Plackett–Burman experiments were conducted to screen significant contact mechanical parameters, while steepest ascent and Box–Behnken experiments were employed to define their value ranges. A neural network model for predicting the angle of repose was constructed, and a genetic algorithm was applied to optimize the significant contact mechanical parameters. The cross-sectional profiles of the pressing hole were obtained through image profile feature extraction in simulation and 3D scanning projection methods in the experiment. The calibrated inter-particle dynamic friction coefficient, inter-particle coefficient of restitution, dynamic friction coefficient between particles and stainless steel, and JKR surface energy of the substrate were 0.0349, 0.5448, 0.0233, and 0.4279, respectively. The deviation of the simulated angle of repose utilizing the optimized contact parameters was 0.4°. The shapes of the pressed holes obtained from simulation and experiment showed good consistency. The pressing speed had no significant effect on the mean depth of all sampling points, suggesting that a higher pressing speed should be set to improve the operation efficiency. The pressing depth has a highly significant effect on the mean depth of all sampled points, but no significant effect on the deviation between the simulated and experimental mean depths. The maximum difference in the mean depth deviation between simulated and experimental sampled points is 1.308 mm. It demonstrates that the established discrete element model can efficiently and accurately simulate the deformation of the pressing hole in sowing substrate. It provides an applicable simulation model for fast optimization design of the pressing hole and sowing equipment. Full article

Metal–organic frameworks (MOFs) based on the pressure swing adsorption (PSA) process show great promise in separating argon from air. As research burgeons, the number of MOFs has grown exponentially, rendering the experimental identification of materials with significant gas separation potential impractical. This study introduced a high-throughput screening through a two-step strategy based on structure–property relationships, which leveraged Grand Canonical Monte Carlo (GCMC) simulations, to swiftly and precisely identify high-performance MOF adsorbents capable of separating argon from air among a vast array of MOFs. Compared to traditional approaches for material development and screening, this method significantly reduced both experimental and computational resource requirements. This research pre-screened 12,020 experimental MOFs from a computationally ready experimental MOF (CoRE MOF) database down to 7328 and then selected 4083 promising candidates through structure–performance correlation. These MOFs underwent GCMC simulation assessments, showing superior adsorption performance to traditional molecular sieves. In addition, an in-depth discussion was conducted on the structural characteristics and metal atoms among the best-performing MOFs, as well as the effects of temperature, pressure, and real gas conditions on their adsorption properties. This work provides a new direction for synthesizing next-generation MOFs for efficient argon separation in labs, contributing to energy conservation and consumption reduction in the production of high-purity argon gas. Full article

The precise real-time detection of polytetrafluoroethylene (PTFE) emulsion rotary vibration sieve levels is critical for improving production efficiency, ensuring product quality, and safeguarding personnel safety. This research presents a deep-learning-oriented video surveillance model for the intelligent level detection of vibrating screens, waste drums, and emulsion outlets, effectively addressing the limitations of traditional methods. With the introduction of TransResNet, which combines Vision Transformer (ViT) with ResNet, we can utilize the advantages of both approaches. ViT has excellent global information capture capability for processing image features, while ResNet excels in local feature extraction. The combined model effectively recognizes level changes in complex backgrounds, enhancing overall detection performance. During model training, synthetic data generation is used to alleviate the marker scarcity problem and generate synthetic images under different liquid level states to further enrich the training dataset, solve the issue of unequal data distribution, and enhance the model’s capacity to generalize. In order to validate the efficacy of our proposed model, we carried out a performance test with real-world data obtained from a material production site. The test results show that the model achieves 96%, 99%, and 99% accuracy at three test points, respectively: the vibrating screen, waste drum, and emulsion. These results not only prove the efficiency of the model but also highlight its significant value in practical applications. Full article

This paper presents the design, implementation, and testing of an automated sieve system tailored for lunar regolith sorting to support ISRU applications, specifically targeting particles of 500 μm size. The design incorporates an approach to mitigate sieve blocking, crucial for effective regolith particle separation, utilizing natural frequencies and adjustable sieve angles. The results indicate the system’s effectiveness in separating regolith simulant fractions, with notable variations in sieving efficiency and sieve blocking observed based on sieve angles, simulant types, and aperture sizes. Further investigations include evaluating the influence of amplitude and moisture content on sieving efficiency and analyzing sieve blocking tendencies. Despite variations in simulant behavior and operational parameters, the prototype demonstrates promising performance, characterized by tight confidence intervals in measured results. Full article

Diatoms are critical indicators in marine paleoecology and contemporary ecosystem studies, yet the accuracy of diatom analysis depends on effective purification methods. Current screening and purification techniques often yield low accuracy. This study introduces a multi-stage screening purification method that integrates both physical and chemical techniques to enhance the extraction of diatom remains from marine sediments, thereby improving the reliability of subsequent analysis. Using surface sediment samples from the Pacific Ocean, we compared the effectiveness of three purification methods: heavy liquid suspension purification, single-layer screening purification, and the newly developed multi-stage screening purification method. The study aimed to evaluate the impact of each method on diatom abundance, valve size distribution, and the accuracy of taxonomic identification. The results revealed that the multi-stage method significantly improved the accuracy of diatom abundance calculation. With this method, diatom abundance was 21.9 times higher than that obtained using the heavy liquid suspension method and 6.5 times higher than that obtained using the single-stage method. This method also proved to be cost-effective, easy to use, and produced samples with low impurity levels, which enhanced microscopic observation, identification, and the reliability of taxonomic statistics. Key factors influencing diatom abundance included sieve pore size, heavy liquid concentration, and valve size and density, while the type of acid and oxidant had minimal effect. Additionally, the multi-stage screening method facilitated the classification of diatoms into various size categories, providing a comprehensive view of diatom size distribution, including nano-sized diatoms (diameter < 20 μm) that are often overlooked in traditional studies. These findings demonstrate that the multi-stage screening purification method is an effective tool for improving the analysis of diatom remains in sediments, potentially refining the accuracy of diatom-based environmental investigations and paleoceanographic reconstructions. Full article

The integrated gasification combined cycle is a relatively new and eco-friendly power generation technology. However, this process produces coal gasification slag (CGS) as a by-product, which is usually landfilled or discarded. To enable efficient recycling of CGS, this study investigated the effects of using pretreated CGS as a fine aggregate on the quality and durability of concrete. A pretreatment system comprising sieve screening, size reduction, and wet flotation processes was devised. Experiments were conducted to evaluate the properties and durability of concrete prepared using mixtures of pretreated or non-pretreated CGS, ordinary Portland cement, crushed gravel, and crushed sand (CS). The results demonstrate that pretreated CGS (P_CGS) reduces the amounts of water-reducing and air-entraining agents required. In particular, it reduces the losses of air content induced when using CGS. P_CGS effectively increases the compressive strength of concrete; however, the strength decreases by 8–10% if the CGS content is >50%. P_CGS exhibits durability similar to that of commonly used CS, indicating its potential applicability as a valuable recycled construction material and safe aggregate for enhancing concrete durability. Full article

The exploitation of high-performance membranes selective for propylene is important for developing energy-efficient propylene/propane (C₃H₆/C₃H₈) separation technologies. Although metal–organic frameworks with a molecular sieving property have been considered promising filler materials in mixed-matrix membranes (MMMs), their use in practical applications has been challenging due to a lack of interface compatibility. Herein, we adopted a surface coordination strategy that involved rationally utilizing carboxyl-functionalized PIM-1 (cPIM) and ZIF-8 to prepare a mixed-matrix membrane for efficient propylene/propane separation. The interfacial coordination between the polymer and the MOF improves their compatibility and eliminates the need for additional modification of the MOF, thereby maximizing the inherent screening performance of the MOF filler. Additionally, the utilization of porous PIM-1 guaranteed the high permeability of the MMMs. The obtained MMMs exhibited excellent separation performance. The 30 wt% ZIF-8/cPIM-1 membrane performed the best, exhibiting a high C₃H₆ permeability of 1023 Barrer with a moderate C₃H₆/C₃H₈ selectivity of 13.97 under 2 bars of pressure. This work presents a method that can feasibly be used for the preparation of defect-free MOF-based MMMs for specific gas separations. Full article