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Septic tanks are widely adopted in decentralized household wastewater treatment systems serving billions of people globally. Due to the lack of effective electron acceptors, insufficient nutrient removal and the emission of harmful gases, e. g. H2S, CH4, etc., are the common drawbacks. In the present work, we attempted to supplement nitrite into septic tanks as an electron acceptor, via nitrifying human urine source-separated from blackwater, to overcome these drawbacks. Partial or complete nitritation of source-separated urine was achieved in a sequencing batch reactor. The addition of nitrified urine into septic tanks improved organic and nitrogen removals in blackwater up to 90 % and 70 %, respectively. The emission of harmful gases from the septic tanks was stably diminished, with more than 75 % of CH4, CO2 and H2S reductions. Nitrite addition significantly reduced the abundance of hydrogenotrophic methanogens in septic tanks. Though the activity of sulfate-reducing bacteria recovered after the initial inhibition upon nitrite addition, the bio-generated H2S was retained in water since the increased wastewater pH after nitrite addition promoted the disassociation of H2S in aqueous solution.

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The versatility of metal-organic frameworks (MOFs) has led to groundbreaking applications in a wide variety of fields, especially in the areas of energy, environment, and sustainability. For example, MOFs can be designed for high uptake of toxic gases and pollutants, such as CO2, NH3, and SO2, but designing a single MOF that shows tangible uptake for all of these gases is challenging due to the differences in the chemical and physical properties of these molecules. To this end, integrating multiple MOFs onto textile fibers and crafting various structures have emerged as pivotal developments, enhancing framework durability and usability. MOF composites prepared on readily available textile fibers offer the flexibility essential for critical applications, including heterogeneous catalysis, chemical sensing, toxic gas adsorption, and drug delivery, while preserving the unique characteristics of MOFs. This study introduces a scalable and adaptable method for seamlessly embedding multiple high-performing MOFs onto a single textile fiber using a dip-coating method. We explored the uptake capacity of these multi-MOF composites for CO2, NH3, and SO2 and observed a performance similar to that of traditional powdered materials. Along with harmful gas adsorption, we also have evaluated the permeation and reactivity of these MOF/textile composites toward chemical warfare agents (CWAs) like GD (soman), HD (mustard gas), and VX. In combination, these results demonstrate a fundamental advancement toward establishing a consistent strategy for the hydrolysis of nerve agents in real-world scenarios. This approach can substantially increase the protection toward CWAs and enhance the effectiveness of protective equipment such as fabrics for protective garments. This dip-coating method for the integration of multiple MOFs on a single textile fiber unlocks a wealth of possibilities and paves the way for future innovations in the deployment of MOF-based composites.

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Artemisia annua L. is a natural herb with a variety of bioactive substances, which can play a variety of biological functions such as anti-inflammatory, antioxidant, antibacterial and antiviral, and can be used as a potential feed additive. The purpose of this study was to investigate the effects of different doses of Artemisia annua L. water extract (AAWE) on growth performance and intestinal related indicators in broilers. A total of 200 one-day-old Arbor Acre broilers were selected and randomly divided into five treatment groups, with five replicates in each group and eight birds per replicate. The control group was fed a basal diet, whereas the other groups were fed a basal diet supplemented with 0.5, 1.0, 1.5, or 2.0 g/kg AAWE. On d 21, with the increase in AAWE dose, final body weight and feed efficiency showed a quadratic increase effect, whereas feed intake showed a linear reduction effect; however, the apparent metabolic rate of dry matter, crude protein, and ether extract increased quadratically on d 42. In addition, the activity of duodenal chymotrypsin and trypsin, and of jejunal lipase quadratically increased, whereas the intestine crypt depth linearly decreased on d 42. The number of total anaerobic bacteria increased quadratically, whereas the number of Escherichia coli decreased quadratically. The number of Lactobacillus increased linearly, whereas H2S emission linearly decreased on d 21; moreover, NH3 emission (24 h) quadratically decreased on d 42. In conclusion, AAWE promoted the growth performance and intestinal related indicators of broilers.

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The potential application of borophene as a sensing material for gas-sensing devices is investigated in this work. We utilize density functional theory (DFT) to systematically study the adsorption mechanism and sensing performance of χ3-borophene to search for high-sensitivity sensors for minor pollutant gases. We compare the results to those for two Pmmn borophenes. The first-principles calculations are used to analyze the sensing performance of the three different borophenes (2 Pmmn borophene, 8 Pmmn borophene, and χ3-borophene) on five leading harmful gases (CO, NH3, SO2, H2S, and NO2). The adsorption configuration, adsorption energy, and electronic properties of χ3-borophene are investigated. Our results indicate that the mechanism of adsorption on χ3-borophene is chemisorption for NO2 and physisorption for SO2 and H2S. The mode of adsorption of CO and NH3 on χ3-borophene can be both physisorption and chemisorption, depending on the initially selected sites. Analyses of the charge transfer and density of states show that χ3-borophene is selective toward the adsorption of harmful gases and that N and O atoms form covalent bonds when chemisorbed on the surface of χ3-borophene. An interesting phenomenon is that when 8 Pmmn borophene adsorbs SO2, the gas molecules are dismembered and strongly adsorb on the surface of 8 Pmmn borophene, which provides a way of generating O2 while adsorbing harmful substances. Overall, the results of this work demonstrate the potential applications of borophene as a sensing material for harmful gas sensing or removal.

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The quality and yield of cashmere closely affect the economic benefits of cashmere goat farming. Studies have shown that controlling light can have an important impact on cashmere but can also affect the concentration of harmful gases. In order to explore the impact of a short photoperiod on the growth of cashmere and harmful gases in goat houses, 130 female (non-pregnant) Shanbei white cashmere goats, aged 4-5 years with similar body weights, were randomly divided into a control group and a treatment group, with 65 goats in each group. The dietary nutrition levels of the experimental goats were the same, and completely natural light was used in the control group; the light control group received light for 7 h every day (9:30-16:30), and the rest of the time (16:30-9:30 the next day) they did not receive light. The light control treatment was carried out in a control house, and the gas content was analyzed. It was found that a shortened period of light exposure could increase the annual average cashmere production by 34.5%. The content of each gas has a certain functional relationship with the measurement time period, but at the same time, we found that the content of NH3 also changes seasonally. In summary, the use of shortened light periods when raising cashmere goats can significantly increase cashmere production and quality, but at the same time, it will increase the concentration of harmful gases in the goat barn, and ventilation should be increased to ensure the health of the goats and the air quality in the barn.

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The harmful gases produced from coal spontaneous combustion (CSC) can cause the environmental pollution. Being able to predict the experimental minimum period of CSC (EMPCSC) is essential in controlling CSC and effectively reducing harmful gas emissions. To obtain high prediction accuracy, we used three optimization algorithms, namely the genetic algorithm (GA), ant colony algorithm (ACO), and particle swarm optimization algorithm (PSO), to optimize the backpropagation neural network (BPNN). R2, MSE, RMSE, and MAPE were used as evaluation indexes to determine the most accurate prediction model for EMPCSC. Data of 424 coal samples from 15 regions in China were analyzed, with 207 and 217 samples having a spontaneous combustion period of less than 40 days (W) and more than 40 days (V), respectively. The two groups were further distributed between low-temperature slow oxidation (W0 and V0) and low-temperature fast oxidation (W1 and V1). The results indicated that the prediction performance of the BPNN model optimized using PSO (PSO-BPNN) was better than that of the GA-BPNN and ACO-BPNN models. After optimization through PSO, the goodness of fit (R2) of groups W0, W1, V0, and V1 increased from 0.9180, 0.8746, 0.9987, and 0.9782 to 0.9857, 0.9639, 0.9997, and 0.9994, respectively. Therefore, the results can provide a theoretical reference for selecting the optimal neural network model to predict EMPCSC with high accuracy.

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In this study, Bacillus subtilis, Clostridium butyricum and Enterococcus faecalis were made into a probiotic complex (PC). The PC was supplemented in AA+ male broilers' diets to investigate the effects of PC on broiler growth performance, carcass traits, blood indicators, harmful gas emissions in feces and microbiota. Three hundred and sixty 1-day-old AA+ male broilers with an average initial body weight (data) were randomly divided into 3 dietary treatments of 6 replicates each, with 20 birds per replicate. The control group (T0) was fed a basal diet, while the test groups (T1 and T2) were supplemented with 0.025 and 0.05% PC in the basal diet, respectively. The trail was 42 days. The results showed that the supplementation of 0.05% PC significantly (p < 0.05) improved average daily gain (ADG) and average daily feed intake (ADFI) of broilers from 22 to 42 days and 1-42 days. Compared to the control group, the breast rate was significantly higher in T2, and the thymic index was significantly higher than that in T1 treatment (p < 0.05). The addition of PC had no significant effects on antibody potency in broiler serum (p > 0.05), but significantly increased albumin and total protein content in serum (p < 0.05). The addition of PC reduced H2S and NH3 emissions in the feces; the levels of Escherichia coli and Salmonella in the feces were significantly reduced and the levels of Lactobacillus were increased. And the most significant results were achieved when PC was added at 0.05%. Correlation analysis showed a significant positive correlation (p < 0.05) between the levels of E. coli and Salmonella and the emissions of H2S and NH3. Conclusion: Dietary supplementation with a 0.05% probiotic complex could improve the growth performance of broilers and also reduced fecal H2S and NH3 emissions, as well as fecal levels of E. coli and Salmonella, and increased levels of Lactobacillus. Thus, PC made by Bacillus subtilis, Clostridium butyricum and Enterococcus faecalis is expected to be an alternative to antibiotics. And based on the results of this trial, the recommended dose for use in on-farm production was 0.05%.

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Covalent organic frameworks (COFs) with 2D or 3D networks are a class of novel porous crystalline materials, and have attracted more and more attention in the field of gas purification owing to their attractive physicochemical properties, such as high surface area, adjustable functionality and structure, low density, and high stability. However, few systematic reviews about the application statuses of COFs in gas purification are available, especially about non-CO2 harmful gases. In this review, the recent progress of COFs about the capture, catalysis, and detection of common harmful gases (such as CO2, NOx, SO2, H2S, NH3 and volatile pollutants) were comprehensively discussed. The design strategies of COF functional materials from porosity adjustment to surface functionalization (including bottom-up approach, post-synthetic approach, and blending with other materials) for certain application were summarized in detail. Furthermore, the faced challenges and future research directions of COFs in the harmful gas treatment were clearly proposed to inspire the development of COFs.

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In recent years, fire accidents in petrochemical plant areas and dangerous goods storage ports in China have shown a trend of frequent occurrence. Toxic and harmful gases are diffused in the scenes of these accidents, which causes great difficulties for fire fighting and rescue operations of fire fighting forces, and consequently, casualties of firefighters often occur. In order to ensure the safety of firefighters in such places, this paper designs a monitoring system of toxic and harmful gases specially used in fire fighting and rescue sites of fire forces, and establishes the transmission network, monitoring terminal and data processing software of the monitoring system of toxic and harmful gases, establishing the danger model of the monitoring area of toxic and harmful gas-monitoring terminal, and the danger model of fire fighters' working area, fusing the field toxic and harmful gas data, terminal positioning data, and field environmental data, designing the data structure of the input data set and the network structure of the RNN cyclic neural network model, and realizing the dynamic early warning of toxic and harmful gases on site.

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Development of eco-friendly polymer foams is an urgent research topic because of the serious environmental pollution caused by trash heaps and the time-release of harmful gases. Polymer PVC foam using azodicarbonamide as a chemical foaming agent has been highly requested for further improvement due to the residual ammonia gas that continuously leaks out. Here, we demonstrate an effective and costless process for the reduction of releasing ammonia from PVC foams using the overcoat technology of deodorants. We have selected four candidate materials, gelite, zeolite, terra alba, and fumed silica as original materials for the deodorant of ammonia, and they showed an ammonia deodorization rate (ADR) of over 80% without any treatment except the fumed silica. When we over-coated the UV-curing agent mixed deodorants on the PVC foams (thickness ~300 µm), the ADR of the terra alba and zeolite complex foams was remarkably higher than 90%, however, the specific gravity and chromaticity were not changed within 20%. This indicates that our developed process using deodorant layer for ammonia reduction has a high potential for the production of eco-friendly polymer foams.

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Objective: To understand the current status of dust and/or harmful gas exposure in adults aged ≥40 years and corresponding protection in China, and provide evidence for strengthening the occupational protection against dust and harmful gas exposure. Methods: The data were obtained from 2014-2015 COPD surveillance in China. A total of 75 107 adults aged ≥40 years selected through multi-stage stratified cluster sampling from 125 surveillance points in 31 provinces (autonomous regions and municipalities) were surveyed in face to face interviews. Occupational exposure was defined as occupational exposure to dust and/or harmful gas for more than 1 year. The weighted percentages of exposure were estimated by using complex sampling design. Results: Among eligible 71 061 participants, the exposure rate of dust and/or harmful gas was 46.3%. The exposure rate in rural area (51.7%) was significantly higher than that in urban area (40.3%), and the exposure rate in the western area was higher than those in the eastern and central areas (P<0.001). Among the groups with different education level, the exposure rate in those with education level of primary school and below was highest (49.7%, P<0.001). The exposure protection rate was 26.7%, and the exposure protection rate was highest in the eastern area (29.9%), followed by that in the central area (27.0%) and that in the western area (22.9%) The exposure protection rate in urban area was significantly higher than that in rural area, and the exposure protection rate was lowest in those with education level of primary school and below. The regular exposure protection was taken by only 50.7% of the adults surveyed. Conclusion: The exposure rate of dust and/or harmful gas is high in China, while the exposure protection rate is very low. Health education, occupational protection and supervision should be strengthened among those with low education level, and those living in rural area and in the western area.

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Objective: To understand the current status of dust and/or harmful gas exposure in adults aged ≥40 years and corresponding protection in China, and provide evidence for strengthening the occupational protection against dust and harmful gas exposure. Methods: The data were obtained from 2014-2015 COPD surveillance in China. A total of 75 107 adults aged ≥40 years selected through multi-stage stratified cluster sampling from 125 surveillance points in 31 provinces (autonomous regions and municipalities) were surveyed in face to face interviews. Occupational exposure was defined as occupational exposure to dust and/or harmful gas for more than 1 year. The weighted percentages of exposure were estimated by using complex sampling design. Results: Among eligible 71 061 participants, the exposure rate of dust and/or harmful gas was 46.3%. The exposure rate in rural area (51.7%) was significantly higher than that in urban area (40.3%), and the exposure rate in the western area was higher than those in the eastern and central areas (P<0.001). Among the groups with different education level, the exposure rate in those with education level of primary school and below was highest (49.7%, P<0.001). The exposure protection rate was 26.7%, and the exposure protection rate was highest in the eastern area (29.9%), followed by that in the central area (27.0%) and that in the western area (22.9%) The exposure protection rate in urban area was significantly higher than that in rural area, and the exposure protection rate was lowest in those with education level of primary school and below. The regular exposure protection was taken by only 50.7% of the adults surveyed. Conclusion: The exposure rate of dust and/or harmful gas is high in China, while the exposure protection rate is very low. Health education, occupational protection and supervision should be strengthened among those with low education level, and those living in rural area and in the western area.

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Objective To understand the current status of dust and/or harmful gas exposure in adults aged ≥40 years and corresponding protection in China,and provide evidence for strengthening the occupational protection against dust and harmful gas exposure.Methods The data were obtained from 2014-2015 COPD surveillance in China.A total of 75 107 adults aged ≥40 years selected through multi-stage stratified cluster sampling from 125 surveillance points in 31 provinces (autonomous regions and municipalities) were surveyed in face to face interviews.Occupational exposure was defined as occupational exposure to dust and/or harmful gas for more than 1 year.The weighted percentages of exposure were estimated by using complex sampling design.Results Among eligible 71 061 participants,the exposure rate of dust and/or harmful gas was 46.3％.The exposure rate in rural area (51.7％) was significantly higher than that in urban area (40.3％),and the exposure rate in the western area was higher than those in the eastern and central areas (P＜0.001).Among the groups with different education level,the exposure rate in those with education level of primary school and below was highest (49.7％,P＜0.001).The exposure protection rate was 26.7％,and the exposure protection rate was highest in the eastern area (29.9％),followed by that in the central area (27.0％) and that in the western area (22.9％) The exposure protection rate in urban area was significantly higher than that in rural area,and the exposure protection rate was lowest in those with education level of primary school and below.The regular exposure protection was taken by only 50.7％ of the adults surveyed.Conclusion The exposure rate of dust and/or harmful gas is high in China,while the exposure protection rate is very low.Health education,occupational protection and supervision should be strengthened among those with low education level,and those living in rural area and in the western area.