Empty Chamber Research Articles

The impact of heat and humidity changes on laboratory acoustic measurements through perturbation method

The paper relates to the determination of the influence of changes in temperature and relative humidity on the laboratory acoustic measurements results. A series of direct reverberation time measurements was carried out, applying different thermal and humidity conditions in the empty reverberation chamber and reverberation chamber with a sound absorber. The reverberation chamber is mainly used to tests aimed at assessment construction materials and products. The results of acoustic measurements and the related classification of construction materials and products ultimately translate into the comfort and acoustic quality of rooms with special requirements as well as living rooms. Based on the analysis of the results, the significance of the problem related to the influence of air parameters on the results of measurements was demonstrated. The effect of changes in temperature and humidity on the results of calculating the equivalent sound absorbing surface was estimated using the n-perturbation method.

Electrochemical Technique to Characterize the High Temperature Oxidation Behavior of Materials

This work demonstrates an approach using solid state electrochemical cells to study the long-term oxidation of materials at 800 °C. The capability of zirconia-based cells to control the oxygen partial pressure was first evaluated using an empty chamber. For most voltages applied to the pump cell, the steady state sensor voltage matches the pump voltage, leakage rates are low, and response times are short, allowing precise and prompt control over the chamber atmosphere. The technique was validated by measuring the oxidation of niobium and nickel. Niobium was oxidized at pump voltages ranging from 0 mV to +500 mV; decreasing the oxygen partial pressure around the specimen reduces the oxidation rate. Comparing the integrated oxidation rate with the weighed mass gain showed good agreement. Measured oxidation rates for nickel were of order 1 μg h−1, illustrating the sensitivity of this technique. For higher oxidation rates, a depression in oxygen partial pressure was observed around the specimen. Improved control over the oxidation potential was achieved by using a sensor cell to dynamically tune the pump voltage. Rates for both metals are compared to literature reports using other techniques.

Standard technical specifications for methacholine chloride (Methacholine) bronchial challenge test (2023)

Standard technical specifications for methacholine chloride (Methacholine) bronchial challenge test (2023)

The Identification of Bee Comb Cell Contents Using Semiconductor Gas Sensors.

Beekeeping is an extremely difficult field of agriculture. It requires efficient management of the bee nest so that the bee colony can develop efficiently and produce as much honey and other bee products as possible. The beekeeper, therefore, must constantly monitor the contents of the bee comb. At the University of Warmia and Mazury in Olsztyn, research is being carried out to develop methods for efficient management of the apiary. One of our research goals was to test whether a gas detector (MCA-8) based on six semiconductor sensors-TGS823, TGS826, TGS832, TGS2600, TGS2602, and TGS2603 from the company FIGARO-is able to recognize the contents of bee comb cells. For this purpose, polystyrene and wooden test chambers were created, in which fragments of bee comb with different contents were placed. Gas samples were analyzed from an empty comb, a comb with sealed brood, a comb with open brood, a comb with carbohydrate food in the form of sugar syrup, and a comb with bee bread. In addition, a sample of gas from an empty chamber was tested. The results in two variants were analyzed: (1) Variant 1, the value of 270 s of sensor readings from the sample measurement (exposure phase), and (2) Variant 2, the value of 270 s of sensor readings from the sample measurement (measurement phase) with baseline correction by subtracting the last 600 s of surrounding air measurements (flushing phase). A five-time cross-validation 2 (5xCV2) test and the Monte Carlo cross-validation 25 (trained and tested 25 times) were performed. Fourteen classifiers were tested. The naive Bayes classifier (NB) proved to be the most effective method for distinguishing individual classes from others. The MCA-8 device brilliantly differentiates an empty comb from a comb with contents. It differentiates better between an empty comb and a comb with brood, with results of more than 83%. Lower class accuracy was obtained when distinguishing an empty comb from a comb with food and a comb with bee bread, with results of less than 73%. The matrix of six TGS sensors in the device shows promising versatility in distinguishing between various types of brood and food found in bee comb cells. This capability, though still developing, positions the MCA-8 device as a potentially invaluable tool for enhancing the efficiency and effectiveness of beekeepers in the future.

Plasma catalysis: separating plasma and surface contributions for an Ar/N2/O2 atmospheric discharge interacting with a Pt catalyst

Atmospheric pressure non-equilibrium plasmas can form nitrogen oxide (NO x ) compounds directly from nitrogen and oxygen without a catalyst, and at lower catalyst temperatures than would be possible without plasma. In this work, the oxidation of plasma-produced NO from an Ar/N2/O2 non-equilibrium atmospheric-pressure plasma-jet (APPJ) over a platinum-on-alumina powder catalyst was investigated with in-situ infrared spectroscopy. Products downstream of the catalyst bed were analyzed along with catalyst surface species. The catalyst was exposed to plasma at both constant temperature and a cyclic temperature ramp in order to study long-lasting and transient surface changes. Primary incident reactive species to the catalyst were assessed to be NO and O3. Pt-Al2O3 at 350 °C increased oxidation of NO relative to Al2O3 or an empty chamber. The surface state of Pt-Al2O3 evolves during plasma-effluent exposure and requires upwards of 20 min exposure for stabilization compared to Al2O3. Once stable surface conditions are achieved, thermal cycling reveals a repeatable hysteresis pattern in downstream products. At low temperature, oxygen and NO x accumulate on the catalyst surface and react at elevated temperatures to form NO2. Increasing plasma power and O2:N2 ratio increases the hysteresis of the heating relative to the cooling curves in the pattern of NO2 formation. The limitation on NO oxidation at high temperatures was assessed to be Pt-O which is depleted as the catalyst is heated. Once stored species have been depleted, NO oxidation rates are determined by incoming reactants. Two overlapping NO oxidation patterns are identified, one determined by surface reactants formed at low temperature, and the other by reactants arriving at the surface at high temperature. The plasma is responsible for providing the reactants to the catalyst surface, while the catalyst enables reaction at high temperature or storage at low temperature for subsequent reaction.

Performance enhancement of indirect solar dryer with offset strip fins: Experimental investigation and comparative analysis

In the present study, two indirect type solar dryers were designed, fabricated and experimentally investigated, one is equipped with a conventional flat plate collector, and the other is integrated with offset strip fins (OSF). The objective is to study the effect of OSF on the performance of the dryer. A series of experimental tests were conducted at the applied research unit in the semi-arid region of Ghardaia using locally available materials. The first test was starting the solar dryers with an empty chamber and the second with filled product. The peak and average temperature difference at the outlet of the collector were 11.3 and 8 °C respectively, in favor of OSF absorber. The courgette was dried to 0.69 (kg water/kg dry basis) from an initial moisture content of 26.24 (kg water/kg dry basis) in 20 h 18 min and 35 h 45 min in the solar dryer with OSF and without, respectively. The results show a high drying rate using the dryer with OSF compared the dryer with conventional collector. Also, Midilli-Kucuk model provided the best agreements between experimental and predicted moisture ratios. Average effective moisture diffusivity of 1.798x10−09 and 1.179x10−09 m2/s for the dryer with OSF and without, respectively. A 33 % increase in economic efficiency in favor the OSF dryer with 0.95 years payback period. Also, a reduced amount of GHGs makes the dryers environmental friendly.

Variable Bessel Beam Profiles Generated through Refraction by Liquid Media.

Various methods have been employed to produce Bessel beams (BBs), with axicon-based techniques remaining the most efficient. Among the limitations of axicons are manufacturing defects such as oblate tips and difficulty in tuning the generated BBs. In this work, we combine the effect of a blunt-tip axicon with refraction using various combinations of liquid media to generate variable BB intensity profiles. The output BBs from the axicon are made to pass through a custom-built fluid chamber and magnified using a telescope system. When traversing an empty chamber, the Bessel beam core diameter is measured to be 773.8 µm at propagation distance z' = 30 cm. The core diameter increases as the beam passes through a chamber containing different liquids as a result of an effective axicon-telescope distance produced by the indices of refraction of the pertinent fluids. Bessel beams modified by the fluid chamber maintain the properties of non-diffraction and self-healing.

Continuous wave 670nm LED light therapy improves short‐ and long‐term object recognition, locomotion, and reduces phosphorylated tau burden in 3xTgAD mice

AbstractBackgroundPhotobiomodulation (PBM) therapy uses 620‐1100nm red to near‐infrared light to modulate biological processes including neuroinflammation, amyloid and tau oligomerization, and apoptosis. We have shown that 670nm light therapy reduces synaptic vulnerability to amyloid‐β oligomers in wild‐type (WT) mice and reduces tau oligomerization in mouse models of tauopathy. Here we sought to determine if 670nm light therapy could rescue cognitive and motor dysfunction and reduce tau hyperphosphorylation in 14‐to‐18‐month‐old 3xTgAD mice.Method14‐to‐18‐month‐old 3xTgAD mice were treated with continuous‐wave 670nm LED light applied directly to the head for 90s per day, 5 days per week for 4 weeks. 3xTgAD sham and WT controls were held under the LED device with the light turned off for the same amount of time. During the fourth week of treatment, spontaneous locomotor behavior was measured by placing animals in an empty chamber for 10 minutes using ANY‐maze software to track mobility data. Animals were then tested for working memory in the Y maze spontaneous alternation task and short‐and long‐term memory in the novel object recognition task. At the completion of behavioral testing on treatment day 20, brains were collected for western blot analysis of total tau and phospho‐tau (pTau).ResultLight‐treated 3xTgAD mice showed increased distance traveled compared to sham (17.43 ± 3.46 vs. 9.97 ± 3.03, one‐way ANOVA p = 0.03), and decreased immobile episodes (4.50 ± 1.92 vs 10.00 ± 1.83, one‐way ANOVA p = 0.02) in the spontaneous locomotor activity test. Light‐treated animals also showed significant object recognition at 2 hours (DI 32.75 ± 7.71, one sample t‐test p<0.001) and 24 hours (DI 44.14 ± 15.73, one sample t‐test p = 0.001) post‐training. Light treatment also reduced the ratio of hippocampal pTau/Tau in 3xTg AD mice as compared to sham (0.11 ± 0.05 vs. 0.32 ± 0.13, one‐way ANOVA p = 0.04).ConclusionHere we show rescue of locomotor behavior and cognitive dysfunction, and reduction of Tau phosphorylation in the hippocampus of 3xTgAD mice using a non‐invasive transcranial treatment with 670nm LED light. Our data suggest that treatment with 670nm red light could significantly improve cognitive function in AD patients and reduce hyperphosphorylation of tau thus possibly preventing further neurodegeneration.

Structural optimization of distribution zone for large-sized PEMFC with high power density

Proton exchange membrane fuel cell (PEMFC) is an important device to convert clean-fuel hydrogen into electricity, which has the potential to reduce pollutant emission and our dependence on fossil fuels. Of the many development and manufacturing challenges that need to overcome before large-scale commercialization can be realized, one of the most pivotal ones is flow distribution uniformity. To this end, a distribution zone with partially dotted matrix was proposed, and showed much more effectiveness when compared with the un-optimized distribution zone with an empty chamber. The positional and size effect of the dotted matrix was investigated, and results showed that flow uniformity was maximized when the dotted matrix was placed near the gas inlet. Interestingly, less dotted matrix size could achieve better performance, indicating the potential of this approach to reduce manufacturing cost. The optimized system could achieve more uniform flow with standard deviation of 1.808 × 10-8, maldistribution factor of 3.967 × 10-3 and variable coefficient of 0.4143%, more superior to other similar models reported. Furthermore, a full cell-level simulation was also conducted, affirming the superiority of the proposed model with increased power densities and water distribution uniformities.

Cobalt nanoparticles cause allergic contact dermatitis inhumans.

Cobalt (Co) causes allergic contact dermatitis (ACD) and the emerging use of Co nanoparticles (CoNPs) warrants gaining further insight into its potential to elicit ACD in sensitized individuals. The aims of the study were to clarify to what extent CoNPs may elicit ACD responses in participants with Co contact allergy, and to evaluate whether the nanoparticles cause a distinct immune response compared with cobalt chloride (CoCl2) in the skin reactions. Fourteen individuals with Co contact allergy were exposed to CoNPs, CoCl2, a Co-containing hard-metal disc (positive control), and an empty test chamber (negative control) by patch testing. Allergic responses were evaluated clinically by a dermatologist at Days 2, 4 and 7. At Day 2, patch-test chambers were removed, and remaining test-substance and skin-wipe samples were collected for inductive-coupled plasma mass spectrometry (ICP-MS) analysis. Additionally, skin biopsies were taken from patch-test reactions at Day 4 for quantitative real-time polymerase chain reaction analysis, histopathology and ICP-MS analysis of Co skin penetration. Patch testing with CoNPs elicited allergic reactions in Co-sensitized individuals. At all timepoints, clinical assessment revealed significantly lower frequencies of positive patch-test reactions to CoNPs compared with CoCl2 or to the positive control. CoNPs elicited comparable immune responses to CoCl2. Chemical analysis of Co residues in patch-test filters, and on skin, shows lower doses for CoNPs compared with CoCl2. CoNPs potently elicit immune responses in Co-sensitized individuals. Even though patch testing with CoNPs resulted in a lower skin dose than CoCl2, identical immunological profiles were present. Further research is needed to identify the potential harm of CoNPs to human health.

Procedure for characterization and validation of commercial clearance monitors using Monte Carlo simulations

The goal of the present work is to propose and validate a numerical model for the calibration of clearance monitors, aimed at determining conversion factors between the measured count rates and the activity for non-standard radionuclides and geometries. For this, Monte Carlo simulations were carried out using the multipurpose code FLUKA in combination with an offline optimization of the model parameters used to correct the simulation results. Parameter optimization was performed by comparing experimental measurements of point sources in an empty chamber of a clearance monitor with the simulation results, whereas for model validation, the simulation results were compared to measurements of the sources in different geometries. The maximum relative discrepancy between the calculated and measured efficiencies in the validation was <10%. This procedure is relevant for the calibration of clearance monitors used in particle accelerator and nuclear facilities, where a variety of radionuclides, materials and geometries need to be measured and released from regulatory control.

Experimental Investigation on Carbon Dioxide Reduction by Using Post Combustion Carbon Capture System in a Spark-Ignition Engine

Global warming is a serious environmental concern that affects humans, wildlife, and ecosystems. Carbon dioxide reduction is the need of the hour as it a major constituent of global warming. The quantum of carbon dioxide released in the exhaust depends on the number of carbon atoms present in the fuel used. The present study investigates the reduction of engine out carbon dioxide emission. For carbon dioxide reduction post combustion capture sys- tem is used. In post combustion capture system carbon dioxide is absorbed by using absorption catalyst. In this capture system, carbon dioxide is absorbed after the combustion. Among various absorption catalyst, monoethanolamine (MEA) is used, as it can react more quickly with carbon dioxide than other absorbents. Monoethanolamine is continuously injected in the exhaust mani- fold. Empty chamber is added in the exhaust manifold for increasing the resi- dent time of the reaction of amine with carbon dioxide. MEA reacts with carbon dioxide forms ammonium carbamate. Carbamate is approved by the Environ- mental Protection Agency as an inert ingredient, used for insect and rodent control in areas where agricultural products are stored.

Design and Application of a Rock Porosity Measurement Apparatus under High Isostatic Pressure

Rock porosity is a key physical parameter at room temperature and pressure that plays an important role in evaluating reserves of oil and natural gas. Research on rock porosity spans over a hundred years. However, in situ porosity under a high isostatic pressure has not been adequately explored, and the experimental conditions for measuring porosity remain unclear. To investigate the feasibility of porosity measurement under a high isostatic pressure and the optimal choice of experimental conditions for this, we design an experimental apparatus that can achieve isostatic pressure up to 200 MPa to fit the relationship between the void volume of a given sample and the drop in gas pressure in an empty standard chamber. The effect of experimental parameters, such as the initial gas pressure at the inlet, the time needed for the gas to reach equilibrium, and the time needed for vacuuming, on the porosity experiment was examined. A series of porosity experiments under different isostatic pressures of up to 200 MPa were carried out with this apparatus. The results quantitatively verify the degree to which porosity is related to isostatic pressure.

Optimization of Air Flow in the Gasification Chamber of the Gasification Boiler Using the PIV Method

The article deals with the optimization of biomass combustion in a small heat source using the optimal distribution of combustion air. Uneven distribution of combustion air was observed during certification tests and in real operation of the used heat source and has an impact on uneven combustion of biomass in the gasification chamber, on increasing emissions and combustion losses. In the first phase of the research, optimization was carried out using CFD simulations, then a transparent model of a real heat source was created, on which the real distribution of combustion air in the gasification chamber was observed using the Particle Image Velocimetry (PIV) method. The results of CFD simulations and the PIV method led to the optimization of the cross-sectional profiles of the four supply channels for gasification air supply. CFD simulations and subsequent PIV measurements on the experimental device were carried out without real combustion, only the air flow in the empty gasification chamber was investigated. This approach was chosen in order to simplify calculations and experiments and on the assumption that with optimal distribution of combustion air in the empty chamber, there will be an optimal even during real combustion. The flow of primary air in the gasification chamber in real operation is influenced by the size and shape of the inserted biomass and its location in the chamber, and this influence is random and difficult to verify. After optimization, the distribution of the primary combustion air in the gasification chamber is uniform and the same amount of air flows into the chamber through the four combustion air inlets.

Resistance against Fracture in Teeth Managed by Root Canal Treatment on Restoring with Onlays, Inlays, and Endocrowns: A Comparative Analysis

To compare the fracture resistance in teeth managed by root canal treatment after restoring with different types of onlays, inlays, and endocrowns prepared with hybrid ceramics and pulp chambers restored with fiber-reinforced composite and resin composite that were radiopaque, light-cured, and flowable. The present study was carried out on 252 extracted mandibular molars. All the specimens were divided into six groups randomly. Each group consisted of 42 specimens. Group 1 consisted of intact teeth without any access cavity. It was the control group. Group 2 consisted of teeth with endocrown and empty pulp chamber. Group 3 consisted of teeth with mesio-occlusal-distal (MOD) onlay prepared with hybrid ceramics and pulp chamber filled with flowable, light-cured, radiopaque resin composite. Group 4 consisted of teeth with MOD onlay and pulp chamber filled with fiber-reinforced composite. Group 5 consisted of teeth with MOD inlay and pulp chamber filled with flowable, light-cured, radiopaque resin composite. Group 6 consisted of teeth with MOD inlay and pulp chamber filled with fiber-reinforced composite. Inlay, onlay, and endocrowns were prepared with computer-aided design (CAD) and computer-aided machine (CAM) using hybrid ceramics. Universal testing machine was used for the measurement of the fracture resistance of each specimen. Inferential statistics were performed by applying Fisher's exact test and chi-square test. Fracture strength was found to be maximum in the intact teeth group followed by the endocrown. The fracture strength was minimum in the inlay group. The fracture strength was intermediate in the onlay groups. Endocrown showed maximum fracture resistance as compared to the inlay and onlay restorations. Proper management of root canal-treated teeth is one of the greatest challenges for endodontists. It has been observed that tooth preparation design and the material used for the restoration of root canal-treated teeth play a vital role in the resistance against fracture in the teeth.

Effects of Distribution Zone Design on Flow Uniformity and Pressure Drop in PEMFC

A typical flow field plate of proton exchange membrane fuel cells has a distribution zone that connects the input ports and main channel region where major reactions take place. In this study, the effects of two distribution zone designs, i.e., the channel-ridge distribution zone (CRDZ) and dot matrix distribution zone (DMDZ), on the gas distribution uniformity and pressure drop are investigated numerically. For the flow fields with CRDZ, the theoretical mass flow rates and pressure distributions are found to agree with numerical results well. The flow rate distributions in the flow fields become more uniform when the turning angle increases to special angle. To design the flow fields with CRDZ, the channels can be arranged with simple geometry lines in the first step and then optimised with CFD considering the actual size to achieve a more uniform distribution and suitable pressure drop. For the flow fields with DMDZ, the uniformity of gas distribution depends on the shunt and dispersion effects of dot matrix, and the rectification and expansion effects of the distribution chamber. With an increase in porosity of DMDZ, the gas distribution gets better, and it is the most uniform when the distribution zone is an empty chamber.

Assessment of the Particulate Matter Reduction Potential of Climbing Plants on Green Walls for Air Quality Management

Background and objective To improve air quality, particulate matter (PM) can be reduced using green infrastructure. Therefore, in this study, we aimed to determine the particulate matter reduction potential of climbing plants used for green walls, an element of vertical green infrastructure. Methods A sealed chamber with controlled environmental variables was used to assess the PM reduction level caused by climbing plants. PM concentration in the plant chamber was measured after two and four hours of PM exposure, and the reduction potential was assessed based on the leaf area. Results Compared to the empty chamber (Control), the PM reduction speed per hour was higher in the plant chamber, which confirmed that climbing plants contribute to the reduction of PM in the air. The PM reduction speed immediately after exposure in the plant chamber was high, but this slowed over time. Additionally, PM has been continuously reduced in plants with large leaves. As a result of calculating the particulate matter reduction level based on leaf area, it was found that there was a difference by particle size. Actinidia arguta, Parthenocissus tricuspidata, Trachelospermum asiaticum, and Euonymus fortunei var. radicans showed a high reduction effect. The trichomes on the leaf surface of Trachelospermum asiaticum were found to affect PM reduction. Conclusion PM adsorption on the leaf surface is an important factor in reducing its concentration. It was possible to compare different plants by quantifying the amount of PM reduction during a fixed time period. These results can be used as the basic data to select the plant species suitable for urban green walls in terms of PM reduction.

Prebiotic, Probiotic, and Synbiotic Consumption Alter Behavioral Variables and Intestinal Permeability and Microbiota in BTBR Mice.

Given that prebiotics have been shown to improve gut microbiota composition, gastrointestinal symptoms and select behaviors in autism spectrum disorder (ASD), we hypothesized that prebiotic supplementation would improve sociability, communication, and repetitive behaviors in a murine model of ASD. We also examined the effect of a synbiotic (probiotic + prebiotic). Juvenile male BTBR mice were randomized to: (1) control; (2) probiotic (1 × 1010 CFU/d Lactobacillus reuteri RC-14®; now known as Limosilactobacillus reuteri); (3) prebiotic (10% oligofructose-enriched inulin); (4) prebiotic + probiotic (n = 12/group) administered through food for 3 weeks. Sociability, communication, repetitive behavior, intestinal permeability and gut microbiota were assessed. Probiotic and symbiotic treatments improved sociability (92 s and 70 s longer in stranger than empty chamber) and repetitive behaviors (50% lower frequency), whereas prebiotic intake worsened sociability (82 s less in stranger chamber) and increased the total time spent self-grooming (96 s vs. 80 s CTR), but improved communication variables (4.6 ms longer call duration and 4 s higher total syllable activity). Mice consuming probiotics or synbiotics had lower intestinal permeability (30% and 15% lower than CTR). Prebiotic, probiotic, and symbiotic treatments shifted gut microbiota to taxa associated with improved gut health. L.reuteri may help alleviate ASD behavioral symptom severity and improve gut health. The potential use of prebiotics in an ASD population warrants further research.

Removal of Volatile Organic Compounds by Means of a Felt-Based Living Wall Using Different Plant Species

Poor indoor quality affects people’s health and well-being. Phytoremediation is one way in which this problem can be tackled, with living walls being a viable option for places with limited space. The aim of this study was to evaluate the efficiency of five plant species in a living wall to remove Volatile Organic Compounds (VOCs) and to identify whether the type of pollutant has any influence. An enclosed chamber was used to add the contaminants n-hexane and formaldehyde independently. Total VOCs were measured for three days in two scenarios: (1) empty chamber, and (2) chamber with living wall. Five living walls were prepared, each with three plants of the same species: Spathiphyllum wallisii, Philodendron hederaceum, Ficus pumila, Tradescantia pallida, and Chlorophytum comosum. There was no correlation between leaf area/fresh weight/dry weight and the contaminant reduction. In general, all five species were more efficient in reducing TVOCs when exposed to formaldehyde than to n-hexane. Chlorophytum comosum was the most efficient species in reducing the concentration of TVOCs for both contaminants, Spathiphyllum wallisii being the least efficient by far.

Research Article Properties of The Water-Based Paint Mixed With The Purple Bacteria

Recently, as carbon dioxide emission increases, global warming is rapidly progressing, and indoor air quality is also affected. In this study, a functional paint was prepared by mixing purple bacteria in an water-based paint, and carbon dioxide adsorption, alkali resistance, and impact resistance were tested. The mixing ratio of purple bacteria is set to 0, 5, 10, 15 (%), and the carbon dioxide adsorption experiment is divided into the case of no light and the case of light. As a result, In the absence of light, complete sealing is achieved as the carbon dioxide concentration in the empty chamber according to the mixing ratio of purple bacteria is considered to be kept constant as 100%. The carbon dioxide concentration of the paint without the purple bacteria was higher than that of the purple bacteria. In the case of light, the decrease of the carbon dioxide concentration tended to be more active than in the case of no light. There was no difference in alkali resistance and impact resistance when comparing the paint without the purple bacteria and the paint mixed with it. In addition, there was no difference even when the incorporation rate of purple bacteria increased. Finally, as for the viscosity, the faster the fall time of the paint, the lower the viscosity of the paint, and the drying time, the lower the viscosity of the paint, the longer the drying time. Therefore, It is believed that water-based paints mixed with purple bacteria can improve indoor air quality by adsorbing carbon dioxide.