Series Of Filters Research Articles

Bipolar topological spin diode and topological spin transistor in finite size quantum spin Hall insulators

Abstract The miniaturization and stability of electronic devices are becoming increasingly important today. We attempt to provide the theoretical support for designing spintronic devices by numerically investigating spin transport in finite size quantum spin Hall insulators (QSHI) under a perpendicular weak magnetic field. By modifying magnetic field strength, we find the gapped spin up and spin down bands are split to realize a half-metal phase which is a promising candidate for designing an efficient spin filter. Moreover, one of the two energy gaps becomes larger and the other smaller due to the weakened or enhanced coupling between two edge states. Here we propose and demonstrate the spin filter based on a finite size QSHI junction under a magnetic field and the polarity can be inverted by a bias voltage or magnetic field. Interestingly, we find a bipolar spin diode effect that only one spin channel is opened and the other spin channel is closed at positive bias, and the opposite spin electron can be transmitted with negative bias. Two spin filters in series can be a spin transistor, the on and off states can be controlled by spin polarization of one spin filter. We show that the topological spin transistor can be controlled by the gate voltage, and it survives in moderate disorder.

Two serial filters control P2X7 cation selectivity, Ser342 in the central pore and lateral acidic residues at the cytoplasmic interface.

The human P2X7 receptor (hP2X7R) is a homotrimeric cell surface receptor gated by extracellular ATP4- with two transmembrane helices per subunit, TM1 and TM2. A ring of three S342 residues, one from each pore-forming TM2 helix, located halfway across the membrane bilayer, functions to close and open the gate in the apo and ATP4--bound open states, respectively. The hP2X7R is selective for small inorganic cations, but can also conduct larger organic cations such as Tris+. Here, we show by voltage-clamp electrophysiology in Xenopus laevis oocytes that mutation of S342 residues to positively charged lysines decreases the selectivity for Na+ over Tris+, but maintains cation selectivity. Deep in the membrane, laterally below the S342 ring are nine acidic residues arranged as an isosceles triangle consisting of residues E14, D352, and D356 on each side, which do not move significantly during gating. When the E14K mutation is combined with lysine substitutions of D352 and/or D356, cation selectivity is lost and permeation of the small anion Cl- is allowed. Lysine substitutions of S342 together with D352 or E14 plus D356 in the acidic triangle convert the hP2X7R mutant to a fully Cl--selective ATP4--gated receptor. We conclude that the ion selectivity of wild-type hP2X7R is determined by two sequential filters in one single pathway: (i) a primary size filter, S342, in the membrane center and (ii) three cation filters lateral to the channel axis, one per subunit interface, consisting of a total of nine acidic residues at the cytoplasmic interface.

Recalibration of missing low-frequency variability and trends in the North Atlantic Oscillation

Multi-decadal trends in the wintertime North Atlantic Oscillation (NAO) are under-represented by coupled general circulation models (CGCMs), consistent with a lack of autocorrelation in their NAO index series. This study proposes and tests two simple “reddening” approaches for correcting this problem in simulated indices based on simple one parameter short-term (AR; Auto-Regressive order 1) and long-term (FD; Fractional-Difference) time series filters. Using CGCMs from the Coupled Model Intercomparison Project Phase 6 (CMIP6), the FD filter successfully improves the autocorrelation structure of the NAO, and in turn the simulation of extreme trends, while the AR filter is less successful. The 1963–1993 NAO trend is the maximum 31-year trend in the historical period. Raw CGCMs underestimate the likelihood of this trend by a factor of ten but this discrepancy is corrected after reddening. CMIP6 future projections show that long-term (2024–2094) NAO ensemble mean trends systematically increase with the magnitude of radiative forcing: -2.4 to 3.5 hPa/century for low-to-high forcing after reddening (more than double the range using raw output). The related likelihood of future maximum 31year trends comparable to 1963–1993 ranges from 3 to 7% whereas none of these CMIP6 projections simulate this without reddening. Near-term projections of the next 31 years (2024–2054) are less sensitive than long term trends to the future scenario, showing weak-to-no forced trend. However, reddening increases the ensemble range by 74% (to +/-1 standard deviation/decade), which could increase/decrease regional climate change signals in the Northern Hemisphere by magnitudes that are underestimated when using raw CGCM output.

Filter Series Model for Processing Well Water into Drinking Water in the Milala Residential Area, Central House of Pancurbatu District

<p><em>Many methods of processing well water have been previously studied, but there has been no research aimed at reducing the physical, chemical, and microbiological parameters so that the treated water can be directly consumed. This research aims to determine the appropriate thickness of the series filter media and its ability to process well water into drinking water. This type of research is quasi-experimental with a pre-test post-test design. In the initial stage before the intervention, an examination of the physical parameters (turbidity, color, Total Dissolved Solids/TDS), chemical parameters (iron, manganese, hardness), and microbiological parameters (E. coli bacteria) in well water samples was conducted. In the second stage, changes in water parameters were assessed after treatment using the Parallel Filter Model.</em><em> T</em><em>he research results show a percentage reduction in turbidity of well water in the Milala Housing Complex in the Pancurbatu Subdistrict, reaching 90.9% - 100%. The percentage reduction in iron (Fe) content of well water in the Milala Housing Complex is 81.9% - 96.2%. The percentage reduction in manganese (Mn) content of well water is 76.9% - 100%. The percentage reduction in water hardness in the Milala Housing Complex is 58.3% - 97.6%, and the reduction in the presence of E. coli in well water occurred in three out of five locations that initially tested positive for E. coli. The series filter is capable of reducing turbidity, iron (Fe), manganese (Mn), the presence of E. coli, and water hardness in well water. </em></p><p> </p><strong><em>Keywords : Drinking water, filter seri, well water treatment</em></strong>

Green energy-sourced AI-controlled multilevel UPQC parameter selection using football game optimization

The power quality (PQ) has been significantly affected by the integration of intermittent non-conventional sources (NCS) into the local distribution system in addition to the adoption of power electronic technologies to regulate non-linear loads. This article combines the H-bridge cascade five-level unified power quality conditioner (5L-UPQC) with the wind power generation system (WPGS), solar photovoltaic power generation system (SPVGS), and battery storage system (BSS) as an effective approach to address PQ problems. The utilization of the Levenberg–Marquardt backpropagation (LMBP)-trained Artificial neural network controller (ANNC) in the UPQC is recommended for generating appropriate reference signals for the converters. This eliminates the requirement for conventional complex conversions, such as abc, dq0, and αβ. Moreover, the artificial neuro-fuzzy interface system (ANFIS) is recommended for achieving a DC-link balance. Football game optimization (FBGO) is utilized to determine the optimal shunt and series filter characteristics. The major objectives of the proposed system are to reduce the current waveform irregularities, resulting in a decrease in the total harmonic distortion (THD), an enhancement in the power factor (PF), the mitigation of supply voltage imbalances and disturbances, and the maintenance of a steady direct-current link capacitor voltage (DLCV), despite the variations in the load, solar irradiation, and wind velocity. The efficiency of the suggested strategy is assessed using four case studies that involve different loads, variable wind velocities, and source voltage balancing conditions. Based on the simulation studies and obtained results, the suggested method significantly decreases the THD to values of 2.91%, 3.63%, 3.75%, and 3.50%. Additionally, it achieves a power factor of unity, which is considerably lower compared to other multilevel schemes that use the traditional symmetrical reference frame (SRF) and instantaneous reactive power (pq) methods. This design has been executed using the MATLAB/Simulink program.

Topology optimisation for vat photopolymerization 3D printing of ceramics with flushing jet accessibility constraint

ABSTRACT For vat photopolymerization 3D printing technology with high-viscosity ceramic slurry, the cleaning of residual uncured slurry presents a challenging task for lattice-based porous structures. Hence, this study contributes a multi-scale topology optimisation method for lattice-solid hybrid structures dedicated to ceramic vat photopolymerization 3D printing. A novel flushing jet accessibility constraint is proposed, aiming to effectively remove the residual uncured slurry after finishing the vat photopolymerization. Specifically, a multi-material interpolation for graded lattices and solid materials is introduced to form the fundamental of topology optimisation. Then, a series of filtering and projection operations are developed to ensure the accessibility of flushing waters to every location that may have residual ceramic slurry. Accordingly, a multi-scale topology optimisation mathematical model is established and solved with the adjoint sensitivities. 2D and 3D numerical examples are conducted to evaluate the effectiveness of the proposed method. Furthermore, a 3D printing experiment is performed to validate the full water jet accessibility of the optimised structural solution and one pillow bracket part is carried out as a practical application demonstration.

Power quality enhancement of hybrid renewable energy source-based distribution system using optimised uPQC

ABSTRACT Generally, the Battery Energy Storage Systems (BESS) may meet entire load requirements while the wind turbine and PV array are still not providing energy, which enhances the reliability of the power system's distribution. The primary aim of the presented research is to produce a framework for enhancing power quality in hybrid devices attached to renewable sources via an optimised fractional order proportional integral (FOPI) Controller in Unified Power Quality Conditioner (UPQC). The source input is made up of RES. To address the PQ difficulties, the UPQC employs series and shunt filter management techniques. Utilizing suggested Adaptive Bald Eagle optimisation algorithm (ABE-OA), the variables are ideally optimised for greater control. To confirm the effectiveness of the proposed method in PQ enhancement, the effectiveness of the developed system is evaluated to that of previous techniques. The proposed method achieved better rise time of 2042.5 and settling min of 19,999.

Application of the Double Series Filter Technique for the Treatment of Acute Inferior Vena Cava Filter-Mediated Thrombosis

In this study, we examined the safety and effectiveness of removing inferior vena cava (IVC) filters with residual acute thrombosis after endovascular therapy. A retrospective chart review of 712 patients who underwent retrievable IVC filter implantation between July 2018 and December 2022 was conducted. Residual thrombosis with the IVC filter occurred in 18 patients, and the volume of residual acute thrombosis in the IVC filter exceeded 1mL in all cases. Angiography was performed to evaluate the size of the residual thrombosis and its position with respect to the filter. The double series filter technique (first filter, infrarenal IVC filter; second filter, suprarenal IVC filter) was used to remove the filter and thrombosis. We summarize the diagnosis, treatment, and surgical experience of these patients. In this study, 16 of 18 patients (88.9%) demonstrated residual thrombosis in the IVC filter. One patient (5.6%) demonstrated thrombosis located both inside and floating above the filter, and one patient (5.6%) demonstrated thrombosis located both inside and underneath the filter. The technical success rate of double series IVC filter retrieval was 100%. Seventeen patients (94.4%) underwent single-stage suprarenal IVC filter retrieval, and one patient (5.6%, 1/18) underwent two-stage retrieval. In terms of residual thrombosis removal, 14 patients (77.7%) achieved complete removal and 4 patients (22.3%) achieved partial removal. Residual thrombosis could not be removed through the sheath in one patient, so femoral vein thrombectomy was performed. No other procedure-related complications were observed. The median follow-up time was 22.5±6.8months. No recurrence of thrombus symptoms was reported, and B ultrasound and computed tomography demonstrated smooth blood flow in the IVC, renal veins, and pulmonary artery. For patients with residual acute thrombosis on the IVC filter and in whom there was absence of a more appropriate treatment after percutaneous mechanical thrombectomy or catheter-directed thrombolysis therapy, the double series IVC filter technique was a safe approach to improve the IVC filter retrieval rate in the early stage, as well as for simultaneous residual thrombus removal.

A vendor-agnostic, PACS integrated, and DICOM-compatible software-server pipeline for testing segmentation algorithms within the clinical radiology workflow.

Reproducible approaches are needed to bring AI/ML for medical image analysis closer to the bedside. Investigators wishing to shadow test cross-sectional medical imaging segmentation algorithms on new studies in real-time will benefit from simple tools that integrate PACS with on-premises image processing, allowing visualization of DICOM-compatible segmentation results and volumetric data at the radiology workstation. In this work, we develop and release a simple containerized and easily deployable pipeline for shadow testing of segmentation algorithms within the clinical workflow. Our end-to-end automated pipeline has two major components- 1. A router/listener and anonymizer and an OHIF web viewer backstopped by a DCM4CHEE DICOM query/retrieve archive deployed in the virtual infrastructure of our secure hospital intranet, and 2. An on-premises single GPU workstation host for DICOM/NIfTI conversion steps, and image processing. DICOM images are visualized in OHIF along with their segmentation masks and associated volumetry measurements (in mL) using DICOM SEG and structured report (SR) elements. Since nnU-net has emerged as a widely-used out-of-the-box method for training segmentation models with state-of-the-art performance, feasibility of our pipleine is demonstrated by recording clock times for a traumatic pelvic hematoma nnU-net model. Mean total clock time from PACS send by user to completion of transfer to the DCM4CHEE query/retrieve archive was 5 min 32 s (± SD of 1 min 26 s). This compares favorably to the report turnaround times for whole-body CT exams, which often exceed 30 min, and illustrates feasibility in the clinical setting where quantitative results would be expected prior to report sign-off. Inference times accounted for most of the total clock time, ranging from 2 min 41 s to 8 min 27 s. All other virtual and on-premises host steps combined ranged from a minimum of 34 s to a maximum of 48 s. The software worked seamlessly with an existing PACS and could be used for deployment of DL models within the radiology workflow for prospective testing on newly scanned patients. Once configured, the pipeline is executed through one command using a single shell script. The code is made publicly available through an open-source license at "https://github.com/vastc/," and includes a readme file providing pipeline config instructions for host names, series filter, other parameters, and citation instructions for this work.

Robust state-of-charge estimation method for lithium-ion batteries based on the fusion of time series relevance vector machine and filter algorithm

Data-driven methods have been widely employed in the field of Lithium-ion battery state-of-charge (SOC) estimation. However, most of these methods do not impose constraints on the rate of change between adjacent output SOC values, which leads to the issue of output SOC fluctuations when the battery current undergoes significant variations. To address this issue, a fusion algorithm is proposed in this study, which combines the multi-kernel Incremental relevance vector machine (MIRVM) and seasonal autoregressive integrated moving average (SARIMA) within an adaptive Kalman filter (AKF) framework, called SARIMA_AKF_MIRVM(SFR) algorithm. Employing the MIRVM algorithm, we aim to construct a data-driven model capturing the intricate relationship between voltage, current, and SOC of batteries under varying operating conditions. Furthermore, we shall leverage the SARIMA algorithm to establish a time series forecasting model for the adjacent SOC values. Subsequently, we shall introduce the AKF algorithm to filter prediction results associated with the MIRVM algorithm. Additionally, we shall integrate the whale optimization algorithm to obtain the optimal parameter combination for SFR algorithm. The experimental results demonstrate that the SFR algorithm exhibits exceptional generalization capabilities and robustness. The RMSE and MAE for four experimental test conditions remain below 0.3 %, with the maximum MAE reaching a mere 0.14 %.

Design of Filtration System for Aerated Sewage Water

The study investigated the potential of sand and activated charcoal filtration systems to enhance water quality for irrigation by treating aerated sewage effluent from. Setup involved a 60 cm deep sand filter connected as the inlet to another 30 cm deep sand filter and this filter linked as the inlet to a 30 cm deep charcoal filter. These filters were operated in series at hydraulic loading rates (HLR) of 60 m/h and 10 m/h. Notably, operating the filters in series at an HLR of 10 m/h yielded superior effluent water quality compared to an HLR of 60 m/h. System achieved significant removal efficiencies for turbidity, BOD5, COD, Total Nitrogen (Total-N), Total Phosphorous (Total-P) with 71.9%, 54.4%, 71.9%, 44.4%, 39.1%, and 42.9% with a 90 cm deep sand filter at an HLR of 10 m/h, and also with a combination of sand and charcoal filters at an HLR of 25 m/h system achieved 81.6%, 80.3%, 63.5%, 47.5%, and 64.3% respectively. We also examined the chemical characteristics of both untreated and treated sewage water samples, revealing a hierarchy of cation and anion prevalence as follows: Na+ > Ca2+ > Mg2+ > K+ for cations, and Cl- > HCO3- > SO42- > CO32- for anions. Our study demonstrates that the combination of aeration and sand filtration effectively ensures safety by preventing water body pollution and unpleasant odours with high-quality treated wastewater suitable for sustainable agricultural use.

Structural insights into anion selectivity and activation mechanism of LRRC8 volume-regulated anion channels

Volume-regulated anion channels (VRACs) are hexamers of LRRC8 proteins that are crucial for cell volume regulation. N termini (NTs) of the obligatory LRRC8A subunit modulate VRACs activation and ion selectivity, but the underlying mechanisms remain poorly understood. Here, we report a 2.8-Å cryo-electron microscopy structure of human LRRC8A that displays well-resolved NTs. Amino-terminal halves of NTs fold back into the pore and constrict the permeation path, thereby determining ion selectivity together with an extracellular selectivity filter with which it works in series. They also interact with pore-surrounding helices and support their compact arrangement. The C-terminal halves of NTs interact with intracellular loops that are crucial for channel activation. Molecular dynamics simulations indicate that low ionic strength increases NT mobility and expands the radial distance between pore-surrounding helices. Our work suggests an unusual pore architecture with two selectivity filters in series and a mechanism for VRAC activation by cell swelling.

Simulation of Active Sallen Key Notch Filter Circuit Using Circuit Wizard and Its Real Testing

An electronic circuit that functions to block or hold signals with intermediate frequencies (median) and will forward signals between low frequencies and high frequencies is the definition of a Notch Filter. The Band Stop Filter, also often referred to as the Notch Filter, is a combination of a Low Pass Filter and a High Pass Filter connected in parallel. This connection differs from the Band Pass Filter, which connects the Low Pass Filter and High Pass Filter in series. This study aims to discuss the simulation of the Sallen-key notch filter Circuit. The author also conducts real simulations to prove the Circuit by changing or adjusting the value of the components installed in the Circuit so that the frequency response is according to the target. The purpose and role of the Sallen-key notch filter and the working principle of the theory of each filter used. The research method used in the research work is to carry out virtual simulations using virtual simulators and live simulations

Self-Pilot Tone Based Adaptive Threshold RZ-OOK Decision for Free-Space Optical Communications

This paper studies a novel self-pilot tone based adaptive threshold return-to-zero on-off keying (RZ-OOK) decision for free-space optical (FSO) communications. RZ-OOK has the characteristics of impulse series in the spectrum. Therefore, these impulses can be utilized as the pilot tones of the transmitted signal to convey the channel state information (CSI) of FSO links. Then, the CSI signal is extracted using a local oscillator (LO) with the frequencies of the impulse series and low pass filter. Finally, the adaptive threshold decision (ATD) is realized by assigning optimized weight factors into the extracted CSI signal. The proposed adaptive threshold RZ-OOK decision was studied in simulation under various pulse durations of RZ-OOK signal and frequencies of LO. Simulation results demonstrated that RZ-OOK with the proposed impulse tone-extracted CSI signal under optimized weight factor performs close to the conventional ATD under precise CSI knowledge.

Serial virus filtration: A case study evaluating the product-dependent impact of control strategies on process efficiency.

The production of biopharmaceutical products carries an inherent risk of contamination by adventitious viruses. Historically, these manufacturing processes have incorporated a dedicated virus filtration step to ensure product safety. However, challenging process conditions can lead to passage of small viruses to the permeate pool and an overall decrease in the desired virus logarithmic reduction value (LRV) for the process. The implementation of serial virus filtration has improved the robustness of such processes, albeit concerns about increased operating times and process complexity have limited its implementation. This work focused on optimizing a serial filtration process and identifying process control strategies to provide maximum efficiency while ensuring proper controls for process complexity. Constant TMP was identified as the optimal control strategy, which combined with the optimal filter ratio, resulted in a robust and faster virus filtration process. To demonstrate this hypothesis, data with two filters connected in series (1:1 filter ratio) are presented for a representative non-fouling molecule. Similarly, for a fouling product, the optimal setup was a combination of a filter connected in series to two filters operated in parallel (2:1 filter ratio). The optimized filter ratios bring cost- and time-savings benefits to the virus filtration step, thereby offering improved productivity. The results of risk and cost analyses performed as part of this study combined with the control strategy, offer companies a toolbox of strategies to accommodate products with different filterability profiles in their downstream processes. This work demonstrates that the safety advantages of performing filters in series can be achieved with minimal increases in time, cost, and risk.

An Equivalent Differential Method for Active Damping of LCL Type Grid-Connected Inverters With Grid-Side Inductor Voltage Feedback

The differential feedback of grid-side inductor voltage can effectively increase the damping of grid-connected inverters. Compared with proportional feedback of filter capacitor current, it can increase the output impedance of the grid-connected inverters, which is more conducive to reducing the impact of grid background harmonics on the grid-in current. However, there is a differential link in its damping branch, and existing differential implementation methods were pursuing to be ideal differential in wide frequency band, as a consequence, high frequency components of the grid-side inductor voltage are amplified, which affects the quality of grid-in current. For this reason, this paper proposes a band-pass filter in series with a lead compensation unit to replace the ideal differential. The major advantage different from the conventional methods is that the proposed strategy is only equivalent to the ideal differential around the resonance frequency band. Specifically, it features lower gain at low and high frequency bands. Finally, theoretical analysis and experiment results show that the proposed strategy can reduce the influence of the added damping path on the fundamental component of grid-in current and features better suppression effect on the harmonics.

CO2 AND H2S REMOVAL FROM BIOGAS BY USING FOUR MEMBRAN OF INTEREST

Biogas upgrading in Africa remains a huge challenge for producers of small installations due to the high cost of acquisition of all-in-one installations designed and used in developed countries. This study brings a clear idea on some purification methods accessible to these small producers while proposing those optimal for decarbonation and desulphurization of biogas. Starting from the analysis over time of the biogas resulting from the anaerobic digestion of cow dung, the system of NaOH filters and steel wool mounted in series is the one proposed for optimality (with purification capacities respective CO2 of the order of 95.9063 ± 0.0864 % and H2S of 100 %). Better still, the use of a steel wool filter in series with activated carbon (based on coconut shells or bamboo) makes it possible to increase the desulfurization capacity of the latter up to 100 %.

An Effective Method for Improving Low-Frequency Response of Geophone

The natural frequency of traditional velocity sensors such as moving coil geophones limits their measurable low-frequency range, and the damping ratio affects the flatness of the sensor in the amplitude and frequency curves, resulting in variations in sensitivity over the available frequency range. In this paper, the structure and working principle of the geophone are analyzed and its dynamics are modeled. After synthesizing the negative resistance method and zero-pole compensation, two commonly adopted low-frequency extension methods, a method for improving low-frequency response, which is a series filter and a subtraction circuit to increase the damping ratio, is proposed. Applying this method to improve the low-frequency response of the JF-20DX geophone, which has a natural frequency of 10 Hz, results in a flat response to acceleration in the frequency range from 1 to 100 Hz. Both the PSpice simulation and actual measurement show a much lower noise level via the new method. Testing the vibration at 10 Hz, the new method has a 17.52 dB higher signal-to-noise ratio than the traditional zero-pole method. Both theoretical analysis and actual measurement results show that this method has a simple circuit structure, introduces less circuit noise, and has a low-frequency response improvement effect, which provides an approach for the low-frequency extension of moving coil geophones.

Meta-omics profiling of full-scale groundwater rapid sand filters explains stratification of iron, ammonium and manganese removals

Rapid sand filters (RSF) are an established and widely applied technology for groundwater treatment. Yet, the underlying interwoven biological and physical-chemical reactions controlling the sequential removal of iron, ammonia and manganese remain poorly understood. To resolve the contribution and interactions between the individual reactions, we studied two full-scale drinking water treatment plant configurations, namely (i) one dual-media (anthracite and quartz sand) filter and (ii) two single-media (quartz sand) filters in series. In situ and ex situ activity tests were combined with mineral coating characterization and metagenome-guided metaproteomics along the depth of each filter. Both plants exhibited comparable performances and process compartmentalization, with most of ammonium and manganese removal occurring only after complete iron depletion. The homogeneity of the media coating and genome-based microbial composition within each compartment highlighted the effect of backwashing, namely the complete vertical mixing of the filter media. In stark contrast to this homogeneity, the removal of the contaminants was strongly stratified within each compartment, and decreased along the filter height. This apparent and longstanding conflict was resolved by quantifying the expressed proteome at different filter heights, revealing a consistent stratification of proteins catalysing ammonia oxidation and protein-based relative abundances of nitrifying genera (up to 2 orders of magnitude difference between top and bottom samples). This implies that microorganisms adapt their protein pool to the available nutrient load at a faster rate than the backwash mixing frequency. Ultimately, these results show the unique and complementary potential of metaproteomics to understand metabolic adaptations and interactions in highly dynamic ecosystems.

Toluene adsorption performance study of cathode air filter for high-power hydrogen fuel cell vehicles

The durability of polymer electrolyte membrane fuel cells (PEMFCs) is impacted by airborne contaminants, and it is necessary to install a cathode air filter to remove harmful pollutants. To learn more about the effect of key process variables (particle size and bulk density) on the adsorption performance of cathode air filters, the breakthrough behaviour of toluene was evaluated using activated carbon (AC) beds. The results showed that with a decrease in particle size and increase in bulk density, the initial breakthrough ratio was reduced, while the pressure drop increased. The breakthrough time increased from 18 min to 45 min with increasing particle size. In addition, kinetic modelling indicated a dominant role of pore diffusion in the whole adsorption process with an enhanced toluene uptake ratio on carbon with a smaller particle size and higher bulk density. A new evaluation index based on energy consumption was proposed, showing that a decrease in particle size will increase the energy consumption, while a change in carbon density has no obvious effect on the energy consumption. Thus, increasing the bulk density of air filters, such as by utilizing a greater number of carbon cloth filters in series, deserves our attention.