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Particle-fluid system is one of the most popular systems in chemical processes. Owing to complex interface structure and high-velocity turbulence, the momentum and mass transfer exhibit nonlinear characteristics, which pose a great challenge for further study and application. To solve this problem, computational mass transfer (CMT) emerged and has been proved to be effective in deeply exploring the mass transfer behavior of particle-fluid systems. First, this paper reviews recent gas-solid numerical studies of turbulence issues from empirical to theoretical, then discusses interphase mass transfer rate models and the interfacial interaction force. Second, the present study particularly reviews researches on mass transfer process of fixed and fluidized regime by CMT, providing reliable analysis of turbulent anisotropy diffusivity as well as multiscale structure and presenting theoretical instruction for the industrial optimization of mass transfer processes in chemical engineering.

Flue gas and coal bed methane are two important sources of greenhouse gases. Pressure swing adsorption process has a wide range of application in the field of gas separation, and the selection of adsorbent is crucial. In this regard, in order to assess the better adsorbent for separating CO2from flue gas and CH4from coal bed methane, adsorption isotherms of CO2, CH4and N2on activated carbon and carbon molecular sieve are measured at 303.15, 318.15 and 333.15 K, and up to 250 kPa. The experimental data fit better with Langmuir 2 compared to Langmuir 3 and Langmuir–Freundlich models, and Clausius–Clapeyron equation was used to calculate the isosteric heat. Both the order of the adsorbed amount and the adsorption heat on the two adsorbents are CO2 > CH4 > N2. The adsorption kinetics are calculated by the pseudo-first kinetic model, and the order of adsorption rates on activated carbon is N2 ≥ CH4 > CO2, while on carbon molecular sieve, it is CO2 ≥ N2 > CH4. It is shown that relative molecular mass and adsorption heat are the primary effect on kinetics for activated carbon, while kinetic diameter is the main resistance factor for carbon molecular sieve. Moreover, the adsorption selectivity of CH4/N2and CO2/N2were estimated with the ideal adsorption solution theory, and carbon molecular sieve performed best at 318.15 K for both CO2and CH4separation. The study suggested that activated carbon is a better choice for separating flue gas and carbon molecular sieve can be a strong candidate for separating coal bed methane.

The lateral flow immunoassay (LFIA) is a sought-after point-of-care testing platform, yet the insufficient sensitivity of the LFIA limits its application in the detection of tumor biomarkers. Here, a colorimetric signal amplification method, bimetallic nanozyme-mediated in situ-catalyzed reporter deposition (BN-ISCRD), was designed for ultrasensitive cancer diagnosis. The bimetallic nanozyme used, palladium@iridium core–shell nanoparticles (Pd@Ir NPs), had ultrahigh enzyme-like activity, which was further explained by the electron transfer of Pd@Ir NPs and the change in the Gibbs free energy during catalysis through density functional theory calculations. With gastric cancer biomarkers pepsinogen I and pepsinogen II as model targets, this assay could achieve a cutoff value of 10 pg/mL, which was 200-fold lower than that without signal enhancement. The assay was applied to correctly identify 8 positive and 28 negative clinical samples. Overall, this BN-ISCRD-based LFIA showed great merits and potential in the application of ultrasensitive disease diagnosis.

Reading and perceiving complex SQL queries has been a time consuming task in traditional database applications for decades. When it comes to decision support systems with automatically generated and sometimes highly nested SQL queries, human understanding or tuning of these workloads becomes even more challenging. This demonstration explores visualization methods to represent queries as graphs. We developed the QueryScopetool to help visualize and understand critical elements of a query, thereby cutting down the learning curve. We show how the tool allows the user to drill down on particular queries or to find similarly structured queries that may exhibit similar tuning opportunities. The queries shown in the demonstration are taken from real tuning engagements.

Polypeptoids are widely used in biological applications owing to their diverse functions and proteolytic stability. One type of polypeptoids, poly-N-methoxyethylglycine (P-Nmeg), has been found to possess remarkable hydrophilicity and notable properties in terms of protein, cell, and bacterial antifouling. However, the currently known synthesis methods of P-Nmeg include solid-phase synthesis, which is time-consuming and difficult to scale up, and N-substituted N-carboxyanhydride (NNCA) ring-opening polymerization, whose monomers were difficult to store. In this study, we used the chemical stable Nmeg N-phenoxycarbonyl (NPC) as the monomer, which was obtained without the use of highly toxic reactants, such as phosgene or phosphorus halide, to synthesize P-Nmeg under open-vessel conditions. By adding BnNH2as an initiator at 80 °C, we can obtain controllable short chain length P-Nmeg with narrow dispersity.

Efferocytosis and metabolic reprogramming of macrophages play crucial roles in myocardial infarction (MI) repair. TREM2 has been proven to participate in phagocytosis and metabolism, but how it modulates myocardial infarction remains unclear. In this study, we showed that macrophage-specific TREM2 deficiency worsened cardiac function and impaired post-MI repair. Using RNA-seq, protein and molecular docking, and Targeted Metabolomics (LC–MS), our data demonstrated that macrophages expressing TREM2 exhibited decreased SLC25A53 transcription through the SYK-SMAD4 signaling pathway after efferocytosis, which impaired NAD+transport into mitochondria, downregulated SLC25A53 thereby causing the breakpoint in the TCA cycle and subsequently increased itaconate production. In vitro experiments confirmed that itaconate secreted by TREM2+macrophages inhibited cardiomyocyte apoptosis and promoted fibroblast proliferation. Conversely, overexpression of TREM2 in macrophages could improve cardiac function. In summary, our study reveals a novel role for macrophage-specific TREM2 in MI, connecting efferocytosis to immune metabolism during cardiac repair.

The ability of wide-area and fast-revisit observation with beam scanning in both azimuth and elevation dimensions has allowed the airborne real aperture radar to be a hotspot in applications of aircraft formation identification and airborne warning and control system. However, the azimuth-elevation 2-D angular resolution is limited by antenna aperture size. When dealing with azimuth-elevation 2-D angular super-resolution of airborne real aperture radar for aerial targets, the existing super-resolution methods suffer from three problems: model mismatch, range and azimuth-elevation coupling, and high computational complexity, which lead to poor resolution and efficiency for the aerial target resolving. To circumvent this problem, this article proposes an azimuth-elevation 2-D joint super-resolution strategy for airborne real aperture radar. First, we establish an airborne azimuth-elevation 2-D scanning signal model, which accurately represents the migration of velocity in different directions. Then, an azimuth-elevation 2-D range migration correction method is proposed, which eliminates the range and azimuth-elevation coupling. To improve the efficiency of target resolution, a fast conjugate gradient iterative adaptive method is finally derived to rapidly reconstruct the azimuth-elevation 2-D target scatterings. Simulated and real datasets demonstrate that the proposed method is not only suitable for airborne 2-D angular super-resolution, but also achieves a competitive resolution capability with quite lower computational complexity.

Chemical looping combustion (CLC) involving multicomponent particles is favorable for the purpose of capturing CO2with a low energy penalty. While the complex flowing behavior in terms of mixing and segregation of particles makes it a challenge to have a deep understanding of hydrodynamics as well as its application. In this paper, a multifluid model based on the Eulerian–Eulerian approach is introduced for a three-dimensional (3D) simulation of the fluidization process in a chemical looping combustion system with binary particles consisting of heavy glass beads (GBs) and light polyethylene (PE) as two model metal oxides (i.e., oxygen carriers). The multifluid model integrates the kg– εg– ks– εs– Θ formulations for the description of turbulence flow and the EMMS drag for the interaction between particles and gas. With this model, the distributions of pressure and phase velocity as well as the solid circulation rate can be obtained. Also, satisfactory agreements are found between the predictions and experimental data, which validates the proposed model. It is observed that a higher fluidizing velocity in the air reactor (AR) and fuel reactor (FR) results in a higher solid circulation rate with less significant segregation. Increasing the diameter of heavy GB from 98 to 138 μm with a fixed PE diameter of 231 μm leads to a continuous intensification of the segregation behavior in AR and riser as well as FR, while the difference in values of averaged binary-mixture compositions (i.e., averaged light PE weight fraction) between AR and FR shows an inflection point where a relatively equal composition within the two reactors is reached when the GB diameter is 116 μm. Higher fluidizing velocity in loop seals just leads to a higher solid circulation rate, and it almost has no influence on the composition of binary particles in AR and FR, indicating a valve-like function of the loop seals.

While solution micellization of ionic block copolymers (BCP) with randomly distributed ionization sites along the hydrophilic segments has been extensively studied, the roles of positionally controlled ionization sites along the BCP chains in their micellization and resulting micellar structure remain comparatively less understood. Herein, three amphoteric polypeptoid block copolymers carrying two oppositely charged ionizable sites, with one fixed at the hydrophobic terminus and the other varyingly positioned along the hydrophilic segment, have been synthesized by sequential ring-opening polymerization method. The presence of the ionizable site at the hydrophobic segment terminus is expected to promote polymer association toward equilibrium micellar structures in an aqueous solution. The concurrent presence of oppositely charged ionizable sites on the polymer chains allows the polymer association to be electrostatically modulated in a broad pH range (ca. 2–12). Micellization of the amphoteric polypeptoid BCP in dilute aqueous solution and the resulting micellar structure at different solution pHs was investigated by a combination of scattering and microscopic methods. Negative-stain transmission-electron microscopy (TEM), small-angle neutron scattering (SANS), and small-angle X-ray scattering (SAXS) analyses revealed the dominant presence of core–shell-type spherical micelles and occasional rod-like micelles with liquid crystalline (LC) domains in the micellar core. The micellar structures (e.g., aggregation number, radius of gyration, chain packing in the micelle) were found to be dependent on the solution pH and the position of the ionizable site along the chain. This study has highlighted the potential of controlling the position of ionizable sites along the BCP polymer to modulate the electrostatic and LC interactions, thus tailoring the micellar structure at different solution pH values in water.

L-valve is often used as a non-mechanical valve for the circulation of solids in gas–solids fluidized bed (GSFB) due to its advantages in simple construction and easy control. The information on solids circulation rate as well as the hydrodynamics performance of the CFB with L-valve is of great importance for its better control and design. This paper proposes a Eulerian-Eulerian approach based numerical model integrating the computational fluid dynamics (CFD) with turbulent model, the kinetic theory of granular flow (KTGF) and the drag model, thus the solids circulation rate and the local phase velocity as well as solids volume fraction can be predicted simultaneously. With this model, the hydrodynamics performance of the full loop GSCFB with a L-valve is analyzed in detail. It is found that the drag model affects the simulation significantly and the (energy minimization multiscale) EMMS method shows good performance in the full-loop simulation of GSCFB.

In this work, a non-ionic, water-soluble rigid rod polymer was investigated for viability in replacing organic-soluble rigid rod polymers as these legacy rigid polymers require difficult solvents. Producing a rigid, water-soluble polymer that does not suffer from aggregation or ionic effects is a difficult proposition. Herein, the synthesis of a poly(lysine) with a short ethylene glycol side chain, PEGL, was duplicated, based on previous work by Deming et al.and characterized by various techniques. It was discovered that PEGL suffers from aggregation, evidenced by dynamic and static light scattering experiments that showed non-ideal rigid rod behavior and multiple decay rates. PEGL also showed a changing lower critical solution temperature when varying salt concentration. Although PEGL can exhibit a double helix conformation and has non-ionic side chains, the propensity for aggregation precludes PEGL from being used for fundamental polymer investigation.

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The Paternò–Büchi (PB) reaction is a carbon–carbon double bond (C═C)-specific derivatization reaction that can be used to pinpoint the location(s) of C═C(s) in unsaturated lipids and quantitate the location of isomers when coupled with tandem mass spectrometry (MS/MS). As the data of PB-MS/MS are increasingly generated, the establishment of a corresponding data analysis tool is highly needed. Herein, LipidOA, a machine-learning and prior-knowledge-based data analysis tool, is developed to analyze PB-MS/MS data generated by liquid chromatography–mass spectrometry workflows. LipidOA consists of four key functional modules to realize an annotation of glycerophospholipid (GPL) structures at the fatty acyl-specific C═C location level. These include (1) data preprocessing, (2) picking C═C diagnostic ions, (3) de novoannotation, and (4) result ranking. Importantly, in the result-ranking module, the reliability of structural annotation is sorted via the use of a machine learning classifier and comparison to the total fatty acid database generated from the same sample. LipidOA is trained and validated by four PB-MS/MS data sets acquired using different PB reagents on mass spectrometers of different resolutions and of different biological samples. Overall, LipidOA provides high precision (higher than 0.9) and a wide coverage for structural annotations of GPLs. These results demonstrate that LipidOA can be used as a robust and flexible tool for annotating PB-MS/MS data collected under different experimental conditions using different lipidomic workflows.

Zwitterionic ring-opening polymerization (ZROP) of sarcosine-derived N-thiocarboxyanhydrides (Me-NNTAs) can be induced by using 1,1,3,3-tetramethylguanidine (TMG) initiators in CH2Cl2at 25 °C, rapidly producing well-defined polysarcosine polymers with controlled molecular weights (Mn= 1.9–37 kg/mol) and narrow molecular weight distributions (Đ= 1.01–1.12). The reaction exhibits characteristics of a living polymerization, evidenced by pseudo-first-order polymerization kinetics, the linear increase of polymer molecular weight (Mn) with conversion, and the successful chain extension experiments. The polymerization is proposed to proceed via propagating macro-zwitterions bearing a cationic 1,1,3,3-tetramethylguanidinium and an anionic thiocarbamate chain end. The TMG not only initiates the polymerization but also serves to stabilize the thiocarbamate chain end where the monomer addition occurs. Because of the enhanced hydrolytic stability of Me-NNTA, the polymerization can be conducted without the rigorous exclusion of moisture, further enhancing the appeal of the method to access well-defined polysarcosine.

Based on the lens of spatial filter parallel auxiliary assembly and collimation method, aiming at the unloading and locking problem of the filter lens after collimating, a lens parallel adjustable axial locking structure was proposed. A special elastic chuck structure was designed to realize clamping axial friction locking; each branch realized interference fit, and the adjustable structure of “line-line-line” contact realized equivalent fixation through spring pre-tightening. Compared with radial locking, the abrupt error of the axial locking lens in the unloading process of a collimating auxiliary machine was small, and the posture state maintenance and structural response stability were strong. The established homogeneous transformation matrix (HTM) and lens global error showed that the pose torsion roll error of the radial locking structure was significantly suppressed. The relative stability experiment showed that the angular drift error of the lens axial locking structure was ± 0.2 µrad. The design effectively improved the unloading anti-mutation characteristics and stability of the filter lens, which provided an experimental basis for the application of intelligent collimation assisted assembly and adjustment scheme in the upgrading of a high-power laser device.

Interleukin‐37 (IL‐37) is a potent anti‐inflammatory cytokine belonging to the IL‐1 family. This study investigates the regulatory mechanism and reparative effects of IL‐37 on HF‐related human induced pluripotent stem cells derived cardiomyocytes (hiPSC‐CMs) and engineered human heart tissue subjected to hypoxia and H2O2treatment. The contractile force and Ca2+conduction capacity of the tissue are assessed using a stretching platform and high‐resolution fluorescence imaging system. This investigation reveals that IL‐37 treatment significantly enhances cell viability, calcium transient levels, contractile force, and Ca2+conduction capacity in HF‐related hiPSC‐CMs and engineered human heart tissue. Notably, IL‐37 facilitates the upregulation of sarcoplasmic reticulum calcium ATPase 2a (SERCA2a) through enhancing nuclear p‐STAT3 levels. This effect is mediated by the binding of p‐STAT3 to the SERCA2a promoter, providing a novel insight on the reparative potential of IL‐37 in HF. IL‐37 demonstrates its ability to enhance systolic function by modulating myocardial calcium handling via the p‐STAT3/SERCA2a axis in HF‐related engineered human heart tissue (as shown in schematic diagram). The specific regulatory mechanism and repair effect of IL‐37 on HF‐related hiPSC‐CM and human heart tissue are revealed. IL‐37 enhances systolic function by modulating myocardial calcium handling via the p‐STAT3/SERCA2a axis in HF‐related engineered human heart tissue. It will explore more effective solution for the treatment of HF, which has strong clinical significance.

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Phosphatidylethanolamines (PEs), ether-PEs, and phosphatidylserines (PSs) are glycerophospholipids harboring a primary amino group in their headgroups. They are key components of mammalian cell membranes and play pivotal roles in cell signaling and apoptosis. In this study, a liquid chromatography–mass spectrometry (LC–MS) workflow for deep profiling of PEs, ether-PEs, and PSs has been developed by integrating two orthogonal derivatizations: (1) derivatization of the primary amino group by 4-trimethylammoniumbutyryl-N-hydroxysuccinimide (TMAB-NHS) for enhanced LC separation and MS detection and (2) the Paternò–Büchi (PB) reaction for carbon–carbon double bond (C═C) derivatization and localization. Significant improvement of the limit of identification down to the C═C location has been achieved for the standards of PSs (3 nM) and ether-PEs (20 nM). This workflow facilitates an identification of more than 200 molecular species of aminophospholipids in the porcine brain, two times more than those identified without TMAB-NHS derivatization. Importantly, we discovered that the n-10 isomers in C16:1 and C18:1 of aminophospholipids showed elevated contribution among other isomers, which correlated well with an increased transcription of the corresponding desaturase (FADS2) in the human breast cancer cell line (MDA-MB-231) relative to that in the normal cell line (HMEC). The abovementioned data suggest that lipid reprograming via forming different C═C location isomers might be an alternative mechanism in cancer cells.

Delay generated by digital control will inevitably lead to negative damping of Modular Multilevel Converter (MMC), which also has significant impacts on the high-frequency stability of the integrated system. Controller parameter optimization is an effectively method for MMC impedance optimization and high-frequency resonance suppression. This paper firstly extends the sequence impedance model of MMC by considering delay effects, and analyzes the high-frequency impedance characteristics as well as the stability of the MMC integrated system. Then, the effect of delay on the frequency range of MMC shows negative damping can be analyzed quantitatively by a vector diagram. Based on the quantified frequency range, the boundary of controller parameters can be derived. Finally, an MMC impedance optimization method that traversal all the values within the derived parameter boundaries to obtain the optimal controller parameters that maximize the phase margin of the system.

To reduce the frequency deviation and the rate of change of frequency (RoCoF) in a low-inertia power system, some converters are required to provide the frequency response (FR) power normally associated with the frequency deviation and/or the RoCoF, by droop/inertia/PD control. In this article, a rapid power compensation (RPC)-based FR strategy is developed to optimize the ability to compensate grid imbalance power, by fully exploiting the converter idle capacity. To this end, first, mathematical proof demonstrated the improved performance of the RPC strategy in terms of frequency deviation suppression versus droop control, and in terms of RoCoF suppression versus inertia control, with identical converter capacity limit. Moreover, it is proven that the RPC strategy can achieve consistent FR performance with respect to the optimal PD control, i.e., it can maximize the suppression of frequency deviation and RoCoF simultaneously, yet avoiding the limitations due to unknown grid parameters. Finally, by analyzing the operation modes and identifying the pertinent switching logic, the detailed implementation of the proposed RPC strategy is developed. Its superb FR performance is verified by the experiment results in a two-converter low-inertia system, and simulation results in an IEEE four-machine two-area system.

Large number of energy points add great difficulty to construct reactive potential energy surfaces (PES). To alleviate this, exemplar-based clustering is applied to partition the configuration space into several smaller parts. The PES of each part can be constructed easily and the global PES is obtained by connecting all the PESs of small parts. This Divide and Conquer strategy is first demonstrated in the fitting of PES for OH3 with gaussian process regression (GPR) and further applied to construct PESs for CH5 and O+\CH4 with artificial neural networks (NN). The accuracy of PESs is tested by fitting errors and direct comparisons with previous PESs in dynamically important regions. As for OH3 and CH5, quantum scattering calculations further validate the global accuracy of newly fitted PESs. The results suggest that partitioning the configuration space by clustering provides a simple and useful method for the construction of PESs for systems that requires large number of energy points.

High-voltage resistant quasi-solid-state polymer electrolytes (QSPEs) are promising for enhancing the energy density of lithium–metal batteries in practice. However, side reactions occurring at the interfaces between the anodes or cathodes and QSPEs considerably reduce the lifespan of high-voltage LMBs. In this study, a copolymer of vinyl ethylene carbonate (VEC) and poly(ethylene glycol) diacrylate (PEGDA) was used as the framework, with a cellulose membrane (CE) as the supporting layer. Based on density functional theory calculations, 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (Pyr14TFSI), an ionic liquid, was screened because of its lowest unoccupied molecular orbital energy level as a modifying agent for the in situ P(VECx-EGy)/Pyrz/LiTFSI@CE QSPEs synthesis. Pyr14+, with a lithiophobic alkyl chain, forms a dense positive ion shielding layer on the protruding tips of deposited lithium, facilitating uniform and smooth lithium deposition. Pyr14TFSI assists in constructing a stable solid electrolyte interphase (SEI) layer on the Li surface enriched with LiF, Li3N, and RCOOLi. The modulation of lithium deposition behavior on the anode by Pyr14TFSI ensures stable Li plating/stripping for >1500 h. A Li–Cu cell exhibits stable cycling for >200 cycles at a current density of 0.05 mA cm–2, with an average Coulombic efficiency of 92.7%. In situ polymerization ensures that P(VECx-EGy)/Pyrz/LiTFSI@CE QSPEs exhibit excellent interface compatibility with the anode and the cathode. The CR2032 button cell Li|P(VEC1-EG0.06)/Pyr0.4/LiTFSI@CE|LiCoO2demonstrates stable cycling with a negligible capacity decay of 0.083% per cycle for >390 cycles at 25 °C and 0.2 C when using a high-voltage LiCoO2(4.45 V) cathode. Furthermore, a 7.1 mAh pouch cell achieves stable charge–discharge cycles, confirming the pronounced stability of the as-fabricated QSPE at the interfaces of the high-voltage LiCoO2cathode and Li anode.

We investigated the temperature-dependent structural evolution of thermoreversible triblock terpolypeptoid hydrogels, namely poly(N-allyl glycine)-b-poly(N-methyl glycine)-b-poly(N-decyl glycine) (AMD), using small-angle neutron scattering (SANS) with contrast matching in conjunction with X-ray scattering and cryogenic transmission electron microscopy (cryo-TEM) techniques. At room temperature, A100M101D10triblock terpolypeptoids self-assemble into core–corona-type spherical micelles in aqueous solution. Upon heating above the critical gelation temperature (Tgel), SANS analysis revealed the formation of a two-compartment hydrogel network comprising distinct micellar cores composed of dehydrated A blocks and hydrophobic D blocks. At T≳ Tgel, the temperature-dependent dehydration of A block further leads to the gradual rearrangement of both A and D domains, forming well-ordered micellar network at higher temperatures. For AMD polymers with either longer D block or shorter A block, such as A101M111D21and A43M92D9, elongated nonspherical micelles with a crystalline D core were observed at T< Tgel. Although these enlarged crystalline micelles still undergo a sharp sol-to-gel transition upon heating, the higher aggregation number of chains results in the immediate association of the micelles into ordered aggregates at the initial stage, followed by a disruption of the spatial ordering as the temperature further increases. On the other hand, fiber-like structures were also observed for AMD with longer A block, such as A153M127D10, due to the crystallization of A domains. This also influences the assembly pathway of the two-compartment network. Our findings emphasize the critical impact of initial micellar morphology on the structural evolution of AMD hydrogels during the sol-to-gel transition, providing valuable insights for the rational design of thermoresponsive hydrogels with tunable network structures at the nanometer scale.

The design and operation of radial flow adsorber are crucial in large-scale industrial oxygen production, which necessitates accurate prediction of gas-solid transfer behavior. In this work, a developed Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) model combined with the adsorption model is proposed. The developed CFD-DEM model is validated by comparing simulated results with experimental data and empirical correlation. Subsequently, the effect of particle packing structure and particle shapes on the dynamic adsorption process are analyzed in detail. The results reveal the mechanism of particle packing structure affecting axial velocity distribution, showing that uneven distribution of resistance on the outer flow channel side leads to uneven axial velocity distribution in the bed. Compared to cylindrical adsorbents, the use of spherical adsorbents results in a more uniform axial velocity distribution, consequently reducing bed pressure drop. The study holds significant potential for optimizing gas distribution and improving separation efficiency in future industrial applications.

The P(VECx-CEAy)/LiTFSI@CE SPEs possess multi-capabilities, all in one, of dissociating LiTFSI, immobilizing TFSI−and thus setting free more Li+, and smoothly transferring Li+.