Small Channels Research Articles

Potentiation of neuromuscular transmission by a small molecule calcium channel gating modifier improves motor function in a severe spinal muscular atrophy mouse model.

Spinal muscular atrophy (SMA) is a monogenic disease that clinically manifests as severe muscle weakness owing to neurotransmission defects and motoneuron degeneration. Individuals affected by SMA experience neuromuscular weakness that impacts functional activities of daily living. We have used a mouse model of severe SMA (SMNΔ7) to test whether a calcium channel gating modifier (GV-58), alone or in combination with a potassium channel antagonist (3,4-diaminopyridine; 3,4-DAP), can improve neuromuscular function in this mouse model. Bath application of GV-58 alone or in combination with 3,4-DAP significantly restored neuromuscular transmission to control levels in both a mildly vulnerable forearm muscle and a strongly vulnerable trunk muscle in SMNΔ7 mice at postnatal days 10-12. Similarly, acute subcutaneous administration of GV-58 to postnatal day 10 SMNΔ7 mice, alone or in combination with 3,4-DAP, significantly increased a behavioral measure of muscle strength. These data suggest that GV-58 may be a promising treatment candidate that could address deficits in neuromuscular function and strength and that the addition of 3,4-DAP to GV-58 treatment could aid in restoring function in SMA.

The effect of ice cover on velocity and shear stress in a riffle‐pool sequence

AbstractDischarge and channel geometry control velocity and bed shear stress within a reach. Channel roughness (e.g., riffles, pools) and ice cover in winter moderates velocity and shear stress at the bed. This study evaluated velocity profiles across a channel segment with variable bed roughness (e.g., riffles, pools) to determine changes in the position of maximum velocity, maximum velocity magnitude, and resulting bed shear stress estimates when ice cover was present. Using acoustic doppler velocimeter (ADV) and acoustic doppler current profiler (ADCP) high resolution velocity profiles were collected during ice cover, open water, and open water with significant increases in vegetation cover through a riffle‐pool sequence in a low‐order channel in southern Ontario Canada in the first half of 2021. Key findings were that in five of the seven cross‐sections, flow direction was significantly different when ice was present. Additionally, maximum velocities were closer to the bed during ice cover, a common finding in modelling and experimental work, and is confirmed in this field setting. Although maximum velocity magnitudes were not significantly different, derived bed shear stress values under ice were larger. Specifically, under ice conditions, riffle bed shear stress ranged 0–16 N/m2 compared to 0–9 N/m2 in ice free conditions. In the pool, bed shear stress ranged 0–6 N/m2 under ice cover, and 0–5 N/m2 in ice free conditions. Further, as flow levels increased through the spring and summer, this coincided with increased in‐stream vegetation cover, which decreased flow velocities near the bed, and thus decreased bed shear stresses to less than 1 N/m2 in both the riffle and pool sections. The findings indicate that channel evolution processes may be more intense during lower‐stage winter flows when ice is present and has significant implications for channel design, restoration and management strategies used in small channels impacted by ice cover.

An optical and acoustic investigation of microbubble cavitation in small channels under therapeutic ultrasound conditions.

Therapeutic focused ultrasound in combination with encapsulated microbubbles is being widely investigated for its ability to elicit bioeffects in the microvasculature, such as transient permeabilization for drug delivery or at higher pressures to achieve 'antivascular' effects. While it is well established that the behaviors of microbubbles are altered when they are situated within sufficiently small vessels, there is a paucity of data examining how the bubble population dynamics and emissions change as a function of channel (vessel) diameter over a size range relevant to therapeutic ultrasound, particularly at pressures relevant to antivascular ultrasound. Here we use acoustic emissions detection and high-speed microscopy (10 kframes/s) to examine the behavior of a polydisperse clinically employed agent (Definity®) in wall-less channels as their diameters are scaled from 1200 to 15µm. Pressures are varied from 0.1 to 3MPa using either a 5ms pulse or a sequence of 0.1ms pulses spaced at 1ms, both of which have been previously employed in an in vivo context. With increasing pressure, the 1200µm channel - on the order of small arteries and veins - exhibited inertial cavitation, 1/2 subharmonics and 3/2 ultraharmonics, consistent with numerous previous reports. The 200 and 100µm channels - in the size range of larger microvessels less affected by therapeutic focused ultrasound - exhibited a distinctly different behavior, having muted development of 1/2 subharmonics and 3/2 ultraharmonics and reduced persistence. These were associated with radiation forces displacing bubbles to the distal wall and inducing clusters that then rapidly dissipated along with emissions. As the diameter transitioned to 50 and then 15µm - a size regime that is most relevant to therapeutic focused ultrasound - there was a higher threshold for the onset of inertial cavitation as well as subharmonics and ultraharmonics, which importantly had more complex orders that are not normally reported. Clusters also occurred in these channels (e.g. at 3MPa, the mean lateral and axial sizes were 23 and 72µm in the 15µm channel; 50 and 90µm in the 50µm channel), however in this case they occupied the entire lumens and displaced the wall boundaries. Damage to the 15µm channel was observed for both pulse types, but at a lower pressure for the long pulse. Experiments conducted with a 'nanobubble' (<0.45µm) subpopulation of Definity followed broadly similar features to 'native' Definity, albeit at a higher pressure threshold for inertial cavitation. These results provide new insights into the behavior of microbubbles in small vessels at higher pressures and have implications for therapeutic focused ultrasound cavitation monitoring and control.

Re-assessing the role of the helix bundle crossing in NaK.

Potassium channels play the main role in shaping action potentials across all living organisms. This function is owed to their ability to open and close in response to stimuli, and thus conduct ions in a selective and regulated fashion. Small prokaryotic potassium channels, such as KcsA, have become model systems for investigations of structure, dynamics and function. These channels are amenable to studies by various biophysical techniques and have been used to obtain insight into the molecular mechanisms of ion channel gating and selectivity. In the case of KcsA, the inner gate is allosterically coupled with the selectivity filter, and several ion conduction mechanisms across the selectivity filter have been proposed. To understand how general these gating and selectivity mechanisms are, we have used solution NMR spectroscopy and solid-supported membrane electrophysiology (SSME) to study another small prokaryotic channel NaK. While NaK maintains a very high degree of structural conservation to potassium channel pores, the conformation of the NaK selectivity filter is different. We show that while NaK still displays allosteric coupling between the selectivity filter and the helix bundle crossing, akin to what was observed for KcsA, the helix bundle crossing remains fully open in both conductive and non-conductive channels. In addition, using SSME we find that ion conduction by NaK shows K+ selectivity in the absence of an electric gradient. These observations contrast with the most recent models proposed by NMR and MD simulations on KcsA and other channels.

Mitochondrial function is regulated by mechanosensitive channels in Trypanosoma brucei.

Mechanosensation is an evolutionary conserved trait that allows cells to sense their external and internal conditions, effectively responding to changes in their environment. Beyond the canonical functions such as volume regulation and surface sensing, intracellular mechanosensitive channels play a role in maintaining organelles physiological functions. We have identified a mechanosensitive channel (TbrMscS) homologous to the small conductance mechanosensitive channel found in E. coli. Expression in spheroplasts followed by electrophysiological recordings indicate that TbrMscS is directly activated by tension and has a conductance of 0.2 pS. When expressed in E. coli strains lacking mechanosensitive channels, TbrMscS complemented the function of the mutants, restoring their ability to regulate volume upon osmotic shock. These results confirmed the nature of TbrMscS as a mechanically gated channel and showed the conservation of its role as an osmotic relief valve. In the parasites, the channel is expressed in both life stages, with higher levels in procyclic forms, and localizes to the mitochondria, as expected by its genetic homology with bacterial-like channels. Upon downregulation of the mechanosensitive channel, we observed reduced growth of the parasites, defects in cell volume regulation under hyperosmotic conditions and absence of social motility behavior on semi-solid agar plates. Furthermore, reduction in TbrMscS expression caused dissipation of the mitochondrial membrane potential, showing its participation in the regulation of this organelle. Our results provide the first evidence of mechanosensation in T. brucei and its role in mitochondrial homeostasis in protozoan parasites.

Hydraulic characteristics and flow measurement performance analysis of portable fish-shaped flumes in U-shaped channels

Achieving accurate flow measurement in small channels is important to improve water use efficiency and reduce agricultural water waste. Commonly used fixed flumes have the disadvantages of high construction cost and easily causing local deposition in channels resulting in large measurement errors. There are no such disadvantages fixed type flumes in portable measuring flumes. However, portable flume types are less commonly used, and have not been widely applied. In this study, a streamlined portable fish-shaped cylinder (the plane figure is fish-shaped) was designed for flow measurement based on bionics and critical flow measurement principles. Prototype and numerical simulation experiments were conducted to study the hydraulic characteristics of the fish-shaped flume in U-shaped channels, which were under conditions of different discharges, slopes and contraction ratios. The hydraulic characteristics and flow measurement performance of the portable fish-shaped flume in the U-shaped channels were analyzed. The results showed that the numerical simulation results based on the RNG k-ε three-dimensional turbulence model were in good agreement with the prototype experiment. This study demonstrates that the proposed portable fish-shaped flumes can be used for flow measurement in small channels with the advantages of high measurement accuracy, high portability, small head loss, small upstream turbulence, and high submergence degree.

Evolution of the theoretical description of the isoelectric focusing experiment: III. Carrier ampholyte behavior in transient, bidirectional isotachophoresis.

In modern isoelectric focusing (IEF) systems, where (i) convective mixing is prevented by gels or small cross-sectional area separation channels, (ii) current densities vary spatially due to the presence of electrode vessels with much larger cross-sectional areas than those of the gels or separation channels, and (iii) electrophoretic and diffusive fluxes do not balance each other, stationary, steady-state pH gradients cannot form (open-system IEF). Open-system IEF is currently described as a two-stage process: A rapid IEF process forms the pH gradient from the carrier ampholytes (CAs) in the first stage, then isotachophoretic processes degrade the pH gradient in the second stage as the extreme pI CAs are moved into the electrode vessels where they become diluted. Based on the ratios of the local effective mobilities and the local conductivities ( / values) of the anolyte, catholyte, and the CAs, we pointed out in the preceding paper (Vigh G, Gas B, Electrophoresis 2023, 44, 675-88) that in open-system IEF, a single process, transient, bidirectional isotachophoresis (tbdITP) operates from the moment current is turned on. In this paper, we demonstrate some of the operational features of the tbdITP model using the new ITP/IEF version of Simul 6.

Bendocapillary instability of liquid in a flexible-walled channel

We study the bendocapillary instability of a liquid droplet that part fills a flexible walled channel. Inspired by experiments in which a periodic pattern emerges as droplets of liquid are condensed slowly into deformable microchannels, we develop a mathematical model of this instability. We describe equilibria of the system, and use a combination of numerical methods and asymptotic analysis in the limit of small channel wall deflections, to elucidate the key features of this instability. We find that configurations are unstable to perturbations of sufficiently small wavenumber regardless of parameter values, that the growth rate of the instability is highly sensitive to the volume of liquid in the channel, and that both wetting and non-wetting configurations are susceptible to the instability in the same channel. Insight into novel interfacial instabilities opens the possibility for their control and thus exploitation in processes such as microfabrication.

The 3D-Printing Fabrication of Multichannel Silicone Microreactors for Catalytic Applications

Microstructured reactors (MSRs) are especially indicated for highly demanding heterogeneous catalysis due to the small channel dimensions that minimize diffusional limitations and enhance mass and heat transport between the fluid and the catalyst. Herein, we present the fabrication protocol of the fused filament 3D printing of silicone monolithic microreactors based on a multichannel design. Microchannels of 200 to 800 µm in width and up to 20 mm in length were developed following the scaffold-removal procedure using acrylonitrile butadiene styrene (ABS) as the material for the 3D-printed scaffold fabrication, polydimethylsiloxane (PDMS) as the building material, and acetone as the ABS removing agent. The main printing parameters such as temperature and printing velocity were optimized in order to minimize the bridging effect and filament collapsing and intercrossing. Heterogeneous catalysts were incorporated into the microchannel walls during fabrication, thus avoiding further post-processing steps. The nanoparticulated catalyst was deposited on ABS scaffolds through dip coating and transferred to the microchannel walls during the PDMS pouring step and subsequent scaffold removal. Two different designs of the silicone monolithic microreactors were tested for four catalytic applications, namely liquid-phase 2-nitrophenol photohydrogenation and methylene blue photodegradation in aqueous media, lignin depolymerization in ethanol, and gas-phase CO2 hydrogenation, in order to investigate the microreactor performance under different reaction conditions (temperature and solvent) and establish the possible range of applications.

Two-dimensional stable lattice Boltzmann simulation of turbulent flow in wavy walled channel

In recent years, the lattice Boltzmann equation has developed into a promising technique for computational fluid dynamics (CFD). The lattice Boltzmann model (LBM) approach is derived from the Boltzmann equation and kinetic theory, as opposed to the standard CFD methods that are based on direct discretization of the Navier–Stokes equations. In this paper, Newtonian flow passing through a wavy walled channel has been examined for laminar to turbulent transition by using the LBM. The simple LBM for this problem becomes unstable as the Reynolds number increases and the laminar to turbulent transition begins. When Ehrenfest’s limiters are introduced in the LBM, the simulation becomes stable for higher Reynolds numbers. Two types of channel geometries are studied here, the channel walls of relatively small amplitude and channel walls of large amplitude. Our findings are that for large amplitude channel walls, flow becomes unsteady for lower Reynolds numbers as compared to that for small amplitude channel walls. For large amplitude walls, the vortices formed exhibit periodic shedding inside the channel furrows and remain there. For small amplitude walls, the vortex shedding starts downstream of the channel. The present LBM variant is able to simulate small amplitude channel flow for a Reynolds number Re = 800 and large amplitude channel flow for a Reynolds number R = 570.

Design of additively manufactured hybrid PCM-air heat sink with a two-stage channel for enhancing thermal performance

The heat sink combining solid–liquid phase change and cooling fluid is a feasible thermal management method for aerospace electric equipment with the fluctuating cyclic heat load with long duration, to achieve structural weight reduction and miniaturization. Large temperature variation along the flow direction can lead to local overheating, which limits the effect of lowering the maximum temperature of the heating surface by the PCM and results in a reduction of the solidification rate of the melted PCM. In this study, an innovative structural design for a hybrid PCM-air heat sink (HPHS) with a two-stage channel is proposed to enhance temperature uniformity, reduce the maximum temperature, and maximize the solidification rate for a fluctuating cyclic heat load with long duration. The test sample, consisting of one PCM storage chamber and one two-stage channel with one large and four small channels along the flow direction, is fabricated by additive manufacturing. The experimental data are used to verify the validity of the numerical method for simulating the coupled heat transfer of PCM and cooling air. The heat transfer performance of three design schemes including air-cooled heat sink (AHS), HPHS with a single channel, and HPHS with a two-stage channel is studied based on equal pump power. The results show that the presence of PCM significantly reduces the maximum temperature and improves the temperature uniformity of the heating surface for HPHS compared with AHS. The thermal performance of HPHS is further improved by the replacement of a single channel with a two-stage channel. When the PCM melts almost completely at 130 s, an approximate 13.5 ℃ decrease in maximum temperature is obtained, and the difference between the maximum and minimum temperature on the heating surface is also dropped from 15.8 to 3.5 ℃. Furthermore, the corresponding solidification time of the melted PCM is shortened by 32.34%.

Experimental study of the flow induced by an axial hydrokinetic turbine

The renewable energy policy strongly encourages the use of all renewable sources of energy. The authors started to develop a new hydrokinetic turbine to be implemented in small rivers or water channels with a low investment cost. This paper presents velocity map distribution around a hydrokinetic turbine prototype. Experimental measurements were performed using a Particle Image Velocimetry system in a water channel, while the water velocity and turbine rotation speed were variated. Images are presented in the same rotor position and the rotational flow is captured downstream of the blades, at different turbine operating modes. This paper is part of a larger study on developing an innovative axial hydrokinetic turbine. The resulting velocity distribution will be used to validate the numerical model.

Performance and prediction of baffled cold plate based battery thermal management system

• Heat transfer performance of cold plate with longer and more baffles is better. • Performance of baffled cold plate can be further improved with the increase of s - L . • Requirements for BTMS operating parameters under different conditions are revealed. • Characteristics of baffled cold plate and BTMS can be predicted by neural network. The development of NEV is restricted by the problem of battery thermal safety. BTMS should be lightweight, compact, and efficient. Baffled cold plate with small aspect ratio channels was designed for BTMS. The influence of structure and operating parameters on baffled cold plate and BTMS performance were explored through ANSYS simulation. BP neural network model was established to study the function of performance prediction and application in the fields of BTM. The results show that the comprehensive heat transfer performance of baffled cold plates with longer and more baffles is better. Comprehensive heat transfer performance and temperature uniformity of baffled cold plate can be improved through local connection method, and the optimization effect is enhanced with the increase in left local slit spacing. Under low discharge rate conditions, it’s easier to meet the needs of BTM. When the battery is discharged at 3 C rate, volumetric flow rate needs to reach 1 mL·s -1 at all inlet temperature conditions. Through data processing and modeling, BP neural network predictions of flow and heat transfer characteristics of baffled cold plate and temperature control performance of BTMS are proven accurate. It facilitates the design and optimization of baffled cold plates, and the design and control strategy formulation of BTMS.

Research on User Pairing Techniques Based on NOMA in Cognitive Radio Networks

This paper outlined a Non-Orthogonal Multiple Access (NOMA) grouping transmission scheme for cognitive radio networks. To address the problems of small channel gain difference of the middle part users caused by the traditional far-near pairing algorithm, and the low transmission rate of the traditional Orthogonal Multiple Access (OMA) transmission, a joint pairing algorithm was proposed, which provided multiple pairing schemes according to the actual scene. Firstly, the secondary users were sorted according to their channel gain, and then different secondary user groups were divided, and the far-near pairing combined with (Uniform Channel Gain Difference (UCGD) algorithm was used to group the secondary users. After completing the user pairing, the power allocation problem was solved. Finally, the simulation data results showed that the proposed algorithm can effectively improve the system transmission rate.

Who Moderates on Twitch and What Do They Do?

Volunteer moderators are an increasingly essential component of effective community management across a range of services, such as Facebook, Reddit, Discord, YouTube, and Twitch. Prior work has investigated how users of these services become moderators, their attitudes towards community moderation, and the work that they perform, largely through interviews with community moderators and managers. In this paper, we analyze survey data from a large, representative sample of 1,053 adults in the United States who are active Twitch moderators. Our findings -- examining moderator recruitment, motivations, tasks, and roles -- validate observations from prior qualitative work on Twitch moderation, showing not only how they generalize across a wider population of livestreaming contexts, but also how they vary. For example, while moderators in larger channels are more likely to have been chosen because they were regular, active participants, mods in smaller channels are more likely to have had a pre-existing connection with the streamer. We similarly find that channel size predicts differences in how new moderators are onboarded and their motivations for becoming moderators. Finally, we find that moderators' self-perceived roles map to differences in the patterns of conversation, socialization, enforcement, and other tasks that they perform. We discuss these results, how they relate to prior work on community moderation across services, and applications to research and design in volunteer moderation.

Variations in hydraulic efficiency of the subglacial drainage landsystem control surging and streaming regimes of outlet glaciers

AbstractSurging and streaming of glaciers are modulated by meltwater availability and pressure which controls mechanical coupling at their beds. Using laboratory-scale experimental modelling and palaeoglaciological mapping, we explore how subglacial drainage landsystems control meltwater drainage efficiency and ice flow velocities for terrestrial-based ice lobes resting on flat horizontal and permeable beds. Two end-members regimes, surging and streaming, appear in our experiments. The surge regime is characterised by a rapid increase of drainage efficiency through development of tunnel valleys and their tributaries, thus reducing the duration of ice flow speed-up events by lowering water pressures and increasing ice-bed coupling. Tunnel valleys connected to ice lobe margins, submarginal thrust moraines, reduced ice lobe extensions and ephemeral shear margins are the most distinctive characteristics of this regime. The stream regime is characterised by disconnected channels of smaller dimensions unable to evacuate all the meltwater: this prolonged drainage inefficiency leads to sustained high ice flow velocity and steady shear margins. Small and rectilinear meltwater channels devoid of tributaries, often disconnected from ice lobe margins, and lineation swarms are diagnostic of this regime.

A Case Report of Rare Vocal Cord Hemangioendothelioma in a Paediatric Larynx.

Hemangioendothelioma (HEM) is a vascular tumour which is locally aggressive with a low-grade malignant potential. We present a rare case of HEM arising from the vocal cord of a 10-year-old female child. Video laryngoscopy clearly showed a large vocal cord polyp-like mass attached to middle one-third of left cord. Histopathological examination showed fragments of tissue with a neoplasm composed of spindle cells arranged diffusely admixed with numerous small vascular channels. These specific cells were positive for CD31, CD34, vimentin and ERG. Flexiblescopy and narrow band imaging were performed 3weeks after surgery which showed no residual mass. Treatment of HEM is hampered by lack of proper guidelines and protocol. In this case of localized vocal cord lesion, a wide excision with regular follow up is considered ideal.

Role of Channel Migration and Influencing Hydro-Geomorphic Attributes in Dibru River Basin Using Remote Sensing and GIS

The action of the river is dynamic and exhibits morphological changes over time. River channel migration may take place because of sedimentation, geology, soil properties, geomorphic setup, precipitation, land use pattern, natural bank geometry (e.g., channel width, meander length, meander wavelength, amplitude, the radius of curvature, arc angle, and sinuosity), discharges of various frequencies (Brice 1982, MacDonald et al. 1991, Garcia et al. 1994), distribution of riparian vegetation, and vertical and horizontal heterogeneity of floodplain soils (Motta et al. 2012), etc. are some factors for channel migration. The present study is undertaken in the Dibru River Basin, the left-bank tributary of the Brahmaputra River. To identify the Spatio-temporal changes, satellite imagery is used in the GIS environment. The extraction of the river is done from the GIS software (Arc GIS 10.4) by digitizing process and tries to overlay the different time periods of shifting of the river and find out the rate of magnitude and nature of the river course changes. An interval of 10 years is taken to find the rate of magnitude and nature of changes in the river courses from satellite imagery. The time period is taken from 1977-2020 at 10 years intervals. Along with the rate of river course changes, channel avulsion is also shown with the help of satellite imagery. The Dibru Saikhowa National Park falls within the Dibru river basin, where numerous streams are found, within the national park. The Saikhoa river and Ajuka river flow within the national park. The Sursa river is a small channel linked with the Dangori river. With phases of time, the river made a headward erosion and confluence with the Ajuka river and formed a channel. The Saikhoa river flowed till 1987; due to deposition, the river abandoned its original course. In 1988, the Ajuka river and Sursa river merged and flowed northwest direction. The high discharges of the Lohit river diverted towards the Ajuka and Sursa Rivers and took a new channel named the Lower course of Lohit river within the study area. It can be called an avulsion channel because it changed its direction from its original to a new course in 1990. Since 1990, the course of the channel has been tremendously expanding its length and breadth, causing a flood, bank erosion, and deposition nearby human habitats and Dibru Saikhowa National Park. From the multi-temporal satellite imagery, the river courses were studied, and found the year of avulsion took place in the channel. Multi-temporal satellite imagery is used to identify the channel’s avulsion. An avulsion is the rapid separation of a river channel to form a new course, which is only possible due to flood, high discharge, soil properties or tectonic activity, etc. that creates instability and causes the channel avulsion.

Assessing E-Cadherin and Connexin 43 Gene Expressions in Colorectal Cancer

Objective: Dysregulation of cellular adhesion is one of the main mechanisms responsible for tumor initiation, proliferation, and survival. E-cadherin is a cell adhesion molecule associated with tissue invasion and metastasis in most epithelial cancers. Gap junctions are known as small molecular channels that allow communication between neighboring cells and consist of connexin molecules. Connexin 43 (Cx43) is a gap junction protein that plays a central role in cell-cycle regulation and has an important function in carcinogenesis. The present study aimed to evaluate the expression levels of E-cadherin and Cx43 in colorectal cancer patients using clinical and prognostic parameters. Materials and Methods: The quantitative real-time polymerase chain reaction (qRT-PCR) method was utilized to characterize the expression patterns of the E-cadherin and Cx43 genes in tumor and adjacent non-tumoral colon tissues from 32 colorectal cancer patients. Analysis of gene expression data was carried out using the delta-CT method. Results: The results show the expression level of Cx43 to decrease 14-fold in tumor tissue compared to normal tissue (p&lt;0.05). However, the study could find no significant difference with regard to E-cadherin expression. Conclusion: The research provides valuable clues to the elucidation of tumor development and metastatic processes for further studies.

Computer-aided Screening of High Performance Covalent-Organic Frameworks for Removal of SO2 from Flue Gases

The combustion of fossil fuels can produce sulfur dioxide (SO2), which is a major source of the environmental problems such as acid rain, photochemical smog and ozone depletion. To solve these problems, it is urgent to develop new porous materials that are conducive to remove acid gases such as SO2. In this work, the adsorption and separation properties of SO2 from flue gases (SO2CO2N2) by covalent organic frameworks (COF) were systematically studied based on the grand canonical Monte Carlo simulations. The results of the structure-activity relationships show that the separation performance of SO2 is related to the pore volume (Vpore) and accessible surface area (ASA) of COF materials to some extent. Some promising candidates with high SO2 adsorption capacity and separation selectivity were identified by comprehensive evaluation metrics, and it can found that the existence of appropriate functional group and the small channels are more conducive to gas adsorption. In addition, the energy decomposition and IGM analysis indicate the nature of the adsorption of SO2 on CF3-TFP-TTA is mainly originated from the electrostatic attraction. These results can provide theoretical references for the design and synthesis of novel high-performance adsorptive separation material.