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The spreading behavior of particles has a significant impact on the processing quality of additive manufacturing. Compared with spherical metal material, polymer particles are usually non-spherical in shape. However, the effects of particle shape and underlying mechanisms remain unclear. Here, the spreading process of particles with reconstructed shapes (non-spherical particles decomposed into several spherical shapes by stereo-lithography models) are simulated by integrating spherical particles with the discrete element method. The results show that more cavities form in the spreading beds of particles with reconstructed shapes than those of spheres with blade spreading. Correspondingly, particles with reconstructed shapes have lower packing densities, leading to more uniform packing patterns. Slow propagation speeds of velocity and angular velocity lead to "right-upwards" turning boundaries for particles with reconstructed shapes and "right-downwards" turning boundaries for spherical particles. Moreover, as the blade velocity increases, the packing density decreases. Our calculation results verify each other and are in good agreement with the experiment, providing more details of the behavior of non-spherical particles before additive manufacturing. The comprehensive comparison between polymer non-spherical particles and spherical particles helps develop a reasonable map for the appropriate choice of operating parameters in real processes. [ABSTRACT FROM AUTHOR]

Maintaining a stable level of potassium is crucial for proper bodily function because even a slight imbalance can result in serious disorders like hyperkalemia and hypokalemia. Therefore, detecting and monitoring potassium ion (K+) levels are of utmost importance. Various biosensors have been developed for rapid K+ detection, with aptamer-based biosensors garnering significant attention due to their high sensitivity and specificity. This review focuses on aptamer-based biosensors for K+ detection, providing an overview of their signal generation strategies, including electrochemical, field-effect transistor, nanopore, colorimetric, and fluorescent systems. The analytical performance of these biosensors is evaluated comprehensively. In addition, factors that affect their efficiency, such as their physicochemical properties, regeneration for reusability, and linkers/spacers, are listed. Lastly, this review examines the major challenges faced by aptamer-based biosensors in K+ detection and discusses potential future developments. [ABSTRACT FROM AUTHOR]

The flow behavior of the powder layer significantly affects subsequent dynamic behavior and final quality of the parts fabricated via powder bed-based additive manufacturing. High powder layer quality is the key scientific problem and technical difficulty, however, the dynamic flow behavior of powder particles and its relationship between powder layer quality were not well understood. In this paper, the influences of typical factors including process parameters (relative layer height and blade velocity) and powder properties (particle size and surface energy coefficient) on powder layer quality of polyamide 6 were systematically investigated by discrete element method to understand the mechanism of the powder layer packing behavior at the particle scale. The packing density, structure uniformity, normalized layer thickness, and surface uniformity were introduced to quantitatively characterize the powder layer quality. The mechanisms at the particle scale, including the blocking of particle, force arch, particle velocity distribution, and cohesion effect were discussed in detail. The results showed that a decreasing value particle size/layer height can effectively weaken the blocking effect of particles, improving the continuity and stability of powder flow and inducing a dense and uniform powder layer. The particles with high average velocity in the gap between the blade and baseplate will move forward after the blade leaves, significantly reducing the layer thickness and packing density. Meanwhile, the cohesion force was determined by the particle size and surface energy coefficient, and the cohesion effect dominated the flow behavior of the particles with a small particle size d = 10μm or a large surface energy coefficient γ = 0.2mJ/m2. These findings can provide useful guidance in understanding the flow behavior at the particle scale and improving the powder layer quality. [Display omitted] • The effect of the van der Waals force on powder flow behavior is considered. • The quality of powder layer is quantitatively evaluated by four metrics. • Powder flowability increases with a decreasing value particle size/layer height. • Cohesion effect induces aggregation of particles with d = 10 μm or γ = 0.2 mJ/m2. [ABSTRACT FROM AUTHOR]

Background. Non-small cell lung cancer (NSCLC) is a main cause of cancer-related mortality worldwide. The relationships of the phospholipase C beta (PLCB) enzymes, which are encoded by the genes PLCB1, PLCB2, PLCB3, and PLCB4, with NSCLC have not been investigated. Therefore, the aim of the present study was to identify any correlations between NSCLC prognosis and the expression patterns of PLCB family members. Materials and Methods. The prognostic values of the PLCB gene family members in NSCLC patients were evaluated using the "Kaplan–Meier plotter" database, which includes updated gene expression data and survival information of a total of 1,926 NSCLC patients. The GeneMANIA plugin of Cytoscape software was used to evaluate the relationships of the four PLCB family members at the gene and protein levels. Gene ontology enrichment analysis and KEGG pathway analysis were performed using the Database for Annotation, Visualization, and Integrated Discovery. Results. High mRNA expression levels of PLCB1, PLCB2, and PLCB3 were significantly associated with poor overall survival (OS) of all NSCLC patients and significantly associated with poor prognosis of adenocarcinoma. In contrast, high mRNA expression of PLCB4 was associated with better OS of adenocarcinoma patients. In addition, the expression levels of the PLCB family members were correlated to smoking status, clinical stage, and patient sex but not radiotherapy and chemotherapy outcomes. Conclusions. PLCB1, PLCB2, PLCB3, and PLCB4 appear to be potential biomarkers for the prognosis of patients with NSCLC. The prognostic values of the PLCB genes require further investigations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanofiltration (NF) membranes were prepared using hydroxypropyltrimethyl ammonium chloride chitosan (HACC) as aqueous phase co-monomer. • The surface electropositivity of NF membrane was significantly enhanced with almost constant pore size. • Modified NF membranes demonstrated superb magnesium-lithium separation performance and excellent antibacterial properties. In recent years, the global demand for lithium resources has been constantly rising thanks to the rapid development of the new energy industry. Nanofiltration (NF) membranes with positive charge could achieve high efficiency separation performance of magnesium ion (Mg2+)/ lithium ion (Li+), which provides a useful solution for the extraction and recovery of lithium resources from brine. In this work, hydroxypropyltrimethyl ammonium chloride chitosan (HACC) was introduced into the interfacial polymerization (IP) as co-monomer with piperazine (PIP) to react with trimesoyl chloride (TMC) for preparing positively charged NF membranes. Based on the modulation of IP process by HACC, the thickness of the modified NF membrane separation layer reduced and the hydrophilicity increased, while the pore size had no obvious variation. In addition, the introduction of the quaternary ammonium group in HACC also increased the antibacterial properties of the NF membrane. The optimized NF-HACC-0.3 not only improved the separation factor significantly, but also increased the flux by 2 times compared with the original membrane. This strategy provides a new valuable idea and insight for the preparation and development of Mg2+/Li+ separation NF membranes. [ABSTRACT FROM AUTHOR]

Natural polymer chitosan (CS) has been widely used as emulsifier due to its good stability, salt-resistant, and stimuli-responsive demulsification. However, chitosan is a hydrocarbon structure molecule containing -NH3+ and -OH with low surface activity, which is mainly suitable for some specific oil-water systems such as corn oil and sunflower oil. Appropriate hydrophilic-hydrophobic modification of chitosan by PNIPAM not only increases its surface activity but also introduces a temperature response on chitosan. Pickering emulsions (O/W) formed by CS-PNIPAM were prepared. The stability and response performance of the emulsions were investigated by observing the macroscopic states, microscopic images, droplet size distributions, emulsion emulsification indices, water partition rates, etc. Molecular dynamics and dissipative particle dynamics simulations were used to reveal the distribution pattern of the emulsifiers at the water-oil interface and clarify the stabilization and pH/temperature response mechanism of the emulsions. CS-PNIPAM performs excellent emulsification in various oil phases. The addition of salt ions enhances the stability performance of the emulsion. At low pH, CS will be protonated to break the emulsion, while increasing the pH will deprotonate CS and reform the emulsion. Also, the increase of temperature to 80 °C leads to emulsion breakage due to the agglomeration of PNIPAM. [Display omitted] • The CS-PNIPAM emulsifiers can form stable emulsions within various oil-water mixtures. • The Pickering emulsions remain effective after multiple pH/temperature responsive emulsification-demulsification cycles. • The presence of salt ions enhances the long-term stability of the Pickering emulsions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carboxylated starch nanoparticles (CSNPs) were synthesized and embedded in the separation layer of the nanofiltration membrane. • The aggregated or large CSNPs adsorb the aqueous phase to build an aqueous template during the interfacial polymerization transferring the reaction interface. • The compatibility problem of nanoparticles and separation layer was effectively solved. • The S NaCl/Na2SO4 of the modified nanofiltration membrane reached 180 with more than 2 times improvement in flux. The challenge of poor compatibility between nanoparticles and separation layers in thin film nanocomposite (TFN) nanofiltration (NF) membranes has always plagued the researchers. In this work, a carboxylated starch nanoparticles (CSNPs) were introduced into the polyamide (PA) separation layer of NF membrane by the IP reaction between trimesoyl chloride (TMC) and piperazine (PIP). The agglomerated or large size CSNPs could transfer the reaction interface above the particles through the formation of a water template by adsorption of aqueous phase monomers, which shaped the defect-free separation layer. Furthermore, the reduced thickness and increased density of the separation layer greatly enhanced the separation selectivity of the nanofiltration membrane thanks to the introduction of hydrophilic groups of nanoparticles. The modified membrane achieved a nearly 5-fold improvement in separation selectivity for NaCl and Na 2 SO 4 (S NaCl/Na2SO4 = 180) and a 2-fold increase in the water permeance. In addition, the modified NF membrane also possessed better chlorine-resistance property based on the formation of polyarylester between the reaction of hydroxyl groups in CSNPs and acyl chloride groups in TMC. Such novel aqueous-phase additives provide new insights to effectively solve the compatibility problem between the nanoparticles and separation layers, which is favorable for the commercial production of NF membrane. [ABSTRACT FROM AUTHOR]

Benefiting from the large specific surface area and controllable physical behaviors, sub-micron sized polymer particles (100–1000 nm) have been fabricated as sensors, color displays and energy management devices. The formation mechanisms of sub-micron particles' structure are still not clear. In this work, a DEM model for sub-micron particles is built by applying van der Waals force and electrostatic force in the model. The packing patterns and porosity are validated with experimental results. The packing characteristics including packing patterns, porosity, coordination number (CN) and forces are examined. Clusters and chains structure is found for sub-micron particles, with large porosity but also large coordination number, different with the relationship of porosity and CN of micron particles. Meanwhile, the effect of separation distances and Ha constant and charge amount are investigated. Suitable separation distances for van der Waals force calculation are obtained for different sized sub-micron particles. [Display omitted] • DEM model with f vdw and f ele for sub-micron particles is validated with experiment. • Clusters and chain structure is found for sub-micron particles. • Both large porosity and large CN appears simultaneously for sub-micron particles. • Suitable separation distances are set for van der Waals force calculation [ABSTRACT FROM AUTHOR]

Single-molecule tools enable translating biorecognition events into electrical and optical signals at the single-molecule level. However, the limitations such as poor specificity, low signal-to-noise, low throughput, and lack of proper molecular receptors between analyte and instrument still hamper the development of single-molecule sensing and imaging. DNA nanotechnology harnesses DNA as a building block, making use of programmable base-pairing to assemble strands into complex shapes, or to orchestrate chemical reaction networks. The involvement of DNA nanotechnology in single-molecule tools not only improves the sensitivity and specificity but also provides molecular receptors and rulers in certain applications such as nanopore sensing, mechanochemical sensing, and super-resolution imaging. This review outlines the progress toward DNA nanotechnology and discusses how DNA nanotechnology enhances single-molecule sensing and imaging to address the above-mentioned challenges. • DNA nanotechnology enhances single-molecule toolkits for sensing and imaging. • The advantages of structural and dynamic DNA nanotechnology were presented. • The way how DNA nanotechnology enhanced single-molecule fluorescence, super-resolution imaging, mechanochemical and nanopore sensing was discussed. • Future challenges in DNA nanotechnology associated single-molecule applications. [ABSTRACT FROM AUTHOR]

• A conjoined-electrode structure capable of mitigating electrochemical heterogeneity of lithium-ion batteries is proposed. • Rate capability is improved by 26% at a rate of 3C, and capacity fade rate is reduced by 50% under 1C cycling. • A Self-balancing mechanism explaining the effects of the conjoined-electrode structure is revealed by simulation analysis. • Principles of designing structural parameters are established to maximizing the self-balancing effect. • Great commercialization potential is demonstrated in terms of energy density, thermal effect, and mechanical strength. Electrochemical inhomogeneity of lithium-ion batteries stemming from heterogeneous electrode microstructure adversely affects battery rate-performance, lifetime and safety. It is attributed to manufacturing errors of electrodes in previous studies. However, the significant heterogeneous electrochemistry is still found in commercial battery electrodes with high manufacturing accuracy. Here, we propose a conjoined-electrode structure to improve the electrochemical homogeneity, in which every two adjacent cathodes or anodes are connected through microholes on current collectors. The commercial level pouch lithium-ion battery with the conjoined-electrode structure is fabricated and it displays a better rate capability (26% higher capacity at 3C rate) and a lower capacity degradation rate (decreased by 50% in the cycling tests at 1C rate). A 3-D electrochemical-thermal model is used in simulation with inhomogeneous situations to reveal the self-balancing effects of state of charge, current density, and Li-ion concentration in the conjoined-electrode structure, which facilitate more homogeneous electrochemistry in lithium-ion batteries. The limitation factor of the self-balancing effects varies depending on the structural parameters, which limits the conjoined-electrode structure design. [ABSTRACT FROM AUTHOR]

[Display omitted] • The interfacial polymerization is regulated by the inverse diffusible organic phase additive polypyrrole nanoparticles (PPYN). • The modified reverse osmosis (RO) separation layer features abundant free volume. • The flux of the modified RO membrane increases nearly 3 times compared with the pristine RO membrane without sacrificing separation selectivity. • The modified RO membrane exhibits excellent anti-biofouling property. Highly permeable thin film composite (TFC) reverse osmosis (RO) membranes with abundant free volume are desirable for water treatment. However, the strategy of controlling the microstructure of the separation layer with high free volume rate is still a challenge. In this work, a modified strategy for the preparation of high-performance TFC RO membrane with inverse diffusible polypyrrole nanoparticles (PPYN) as organic phase additive was developed. The combination of PPYN and trimesoyl chloride (TMC) would diffuse backwards from the organic phase into the aqueous phase during the reaction process to disrupt the normal interfacial polymerization (IP) and thus introduce more free volume in the RO membrane due to the nanobubbles from violent reactions. Moreover, the thickness of the modified membrane decreased and the hydrophilicity increased based on the modulation of IP by PPYN, which facilitated the water molecules to transport. The prepared RO-PPYN membranes showed nearly three times the flux compared with the pristine RO membrane without sacrificing separation selectivity. Furthermore, the anti-biofouling property of the modified membrane was also improved. This work successfully demonstrated the potential use of PPYN as an organic filler to enhance the performance of seawater desalination in RO membranes. Our modification strategy provides an efficient and convenient way to prepare novel RO membranes with high permeability. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel polyamide loose NF membrane was prepared from aqueous monomer (piperazine-2-carboxylic acid). • The loose NF membrane formation mechanism was clarified. • The loose NF membrane exhibited high water permeance and outstanding separation selectivity of dye/salt. • The loose NF membrane demonstrated excellent antifouling performance. Dye effluent is regarded as one of the most hazardous industrial effluents. Although loose nanofiltration (NF) membranes have been considered as an effective alternative technique for treating dye effluent, their development is still constrained by subpar permeance, separation efficiency and anti-fouling performance. In this work, a novel loose polyamide (PA) NF membrane was designed employing a conventional interfacial polymerization process using piperazine-2-carboxylic acid (PIP-COOH) and trimesoyl chloride as aqueous and organic phase monomers, respectively. The presence of unique electron-absorbing carboxyl groups on the PIP-COOH monomer not only provided abundant negative charge on the membrane surface, but also greatly reduced the reactivity, diffusion rate and solubility in n-hexane of the aqueous monomer, allowing for the formation of a more relaxed and smoother active layer. The balanced combination of pore size screening and Donnan effect achieved precise separations with high permeability. Moreover, the interaction of the carboxyl groups with the backbone structure increased the free volume of the PA layer and improved permeability significantly. The PIP-COOH/TMC membrane prepared under the optimal conditions exhibited high water permeance of 598.1 L·m−2·h−1·MPa−1, high reactive red rejection (99.3%) and low NaCl rejection (5.4%). Furthermore, the membrane possessed exceptional anti-fouling performance thanks to the ultra-smooth surface with crucial antifouling index flux recovery ratio as high as about 99%, which showed unexpected application possibilities. In conclusion, this study offers a potential novel membrane material for the development and application of loose NF membranes in the treatment of colored effluent. [ABSTRACT FROM AUTHOR]

The Mg2+/Li+ screening selectivity determines the practical application of nanofiltration technology in lithium extraction from salt-lake brines and industrial lithium production. In this work, a membrane structure design strategy based on the interlayers was developed to prepare nanofiltration (NF) membranes with high Mg2+/Li+ separation selectivity and high permeability. Through investigating the influence of the interlayer charge on the structure and performance of the NF membrane, the interlayer for the preparation of the NF membrane with high Mg2+/Li + separation selectivity was screened. Relevant characterizations indicate that the positively charged interlayer can endow the NF membrane with appropriate pore size and surface charge density to achieve high Mg2+/Li+ separation selectivity through the synergistic effect of size sieving and Donnan exclusion. Moreover, the pore size of the NF membrane is controlled by the release rate of the piperazine (PIP) from the interlayer, while the surface charge density of the NF membrane is jointly determined by the charge of the interlayer and PA layer. The performance evaluation suggests that the NF membrane prepared with the best screened interlayer has a Mg2+/Li+ separation factor up to 88.6 while maintaining a high permeability (22.5 L m−2 h−1·bar−1), which is better than that of the most membranes reported in the literature. Overall, this work is expected to promote the practical application of NF membranes in lithium extraction from salt-lake brines and industrial lithium production. [Display omitted] • The positively charged interlayer can endow the NF membrane with very high Mg2+/Li+ separation selectivity (88.6). • The interlayer regulates the pore size of the NF membrane by controlling the release rate of PIP from the interlayer. • The surface charge density of the NF membrane is jointly determined by the interlayer and the PA layer. • The high Mg2+/Li+ separation selectivity is mainly attributed to the synergy between the size sieving and Donnan exclusion. [ABSTRACT FROM AUTHOR]

The stimuli-responsive release could reduce the waste of the corrosion inhibitor and realize the accurate repair of corroded region. In this work, hollow mesoporous organosilica nanoparticles (HMON) were first synthesized by silica-etching chemistry tailoring method. Then, HMON were encapsulated with 2-mercaptobenzothiazole (MBT) corrosion inhibitor molecules to build an intelligent corrosion inhibitor system, i.e., MBT@HMON. The microstructure and frame composition of the synthesized HMON were characterized. After the successful encapsulation of MBT into HMON, the release kinetics of MBT from HMON under different dithiothreitol (DTT) concentration and pH conditions were investigated. Finally, the corrosion inhibition performance of MBT@HMON for copper alloy was evaluated in 3.5 wt% NaCl solution by weight loss test and electrochemical impedance spectroscopy (EIS). The results show that the controlled release of corrosion inhibitor MBT from HMON could be realized by tuning the redox and pH conditions of corrosion medium. When the appropriate concentration of MBT@HMON was added into the corrosion medium (1.6 g·L−1 in this work), the corrosion of cooper alloy was greatly inhibited. This simple and general strategy of introducing corrosion inhibitors loaded HMON directly into the corrosion medium offers a new prospect for the application of nanocontainers in the intelligent corrosion protection of metallic materials. • pH and redox double stimulus-responsive intelligent corrosion inhibitor system was obtained. • Embedded disulfide bonds and interaction between HMON framework and inhibitor served as nature valve. • MBT@ HMON exhibited excellent inhibitor-loading/releasing properties. • Robust corrosion resistance was achieved by MBT@ HMON. [ABSTRACT FROM AUTHOR]

• Simultaneous double-sided slot coating efficiency is twice that of single-sided one. • Contacted slot die boosts coating evenness in simultaneous double-sided slot coating. • Contacted slot die suppresses the gap fluctuation caused by substrate vibration. • Coating uniformity decreases as substrate vibration frequency increases. Simultaneous double-sided slot coating (SDSSC) has been developed to improve the efficiency of lithium-ion battery electrode production, but the coating uniformity is limited owing to the gap fluctuation caused by substrate vibration during coating the second side. Here we investigated the SDSSC with a novel contacted slot die and discussed its coating uniformity. A validated numerical model was established to describe the gap fluctuation and analyze the frequency response of coating uniformity to it. The numerical results indicate the contacted slot die can suppress the gap fluctuation to two orders of magnitude smaller than the non-contact slot die. There is a range of substrate vibration frequencies for guaranteeing the coating uniformity because it decreases with increasing frequency. In experiments with different coating thicknesses and speeds, the coating uniformities all exceeded 95% and improved upon increasing these parameters. The contacted slot die is effective at controlling coating uniformity in SDSSC. [ABSTRACT FROM AUTHOR]