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Nitrogen (N) fertilizer incorporation of efficiency enhancer is a well-established practice aiming at reducing N loss while enhancing crop yield. However, the effect of different kinds of fertilizer efficiency enhancer on N use efficiency (NUE) and gas loss are rarely compared and poorly comprehended. Here, we conducted a field experiment involving the combination of urease and nitrification inhibitor (NI), the biological inhibitor eugenol (DE) and the bioploymer poly-glutamic acid (PG) and their combinations (NI + PG, NI + DE, PG + DE) to evaluate their effects on crop yield, NUE, NH3 volatilization and greenhouse gas emissions (GHGs). Results indicated that NI, DE, PG and their combinations significantly enhanced the crop yield, N uptake and NUE. NI, DE and PG are all effective in reducing NH3 volatilization and N2O emission, averagely decreased by 11.13%, 6.83%, 8.29%, respectively, and by 11.15%, 4.32%, 8.35%, respectively, while have no significant effects on CO2-C and CH4-C fluxes, except PG significantly increases CO2-C emission and thus global warming potential. The combination of these three efficiency enhancers has no multiply effect on maize yield, NUE and gas loss. These findings help to screen the fertilizer efficiency enhancer that can be more effectively utilized in agricultural practices and contribute to their application strategies within agricultural systems. [ABSTRACT FROM AUTHOR]

Abstract Ammonia (NH3) has received considerable attention as a major reduced nitrogen. However, accurate estimates of the deposition amount are difficult due to its complex behavior characterized by bidirectional exchange between the atmosphere and the surface. We observed the vertical profile of NH3 concentration in a deciduous forest in Japan for 1 year to further advance the studies on NH3 bidirectional exchange in Asia, especially focusing on the process near the forest floor. The observation period lasted from September 29, 2020, to September 28, 2021, including leafy and leafless periods. Using the denuder sampling technique, we measured NH3 concentration in the forest at three heights (above the forest canopy, 30 m, and near the forest floor, 2 m and 0.2 m). NH3 concentrations tended to be highest at the top of the canopy (30 m). Focusing on the concentration near the forest floor, the concentrations at 0.2 m were frequently higher than those at 2 m regardless of the leafy and leafless period, thus suggesting NH3 emissions from the forest floor. NH3 concentration near the forest floor showed strong positive correlations with air temperature during the leafy period. The NH3 emissions from the forest floor during the leafy period were possibly due to the decomposition of leaf litter with increased air temperature. The decrease in leaf area index might induced the increase in NH3 concentration and emission. NH3 emission during the leafless period was also possibly dependent on the state of the deposition surface, apart from air temperature, relative humidity, and leaf area index. Graphical Abstract

Composting is a well-known method for waste management, but it causes greenhouse gas emissions. Various techniques have been used to reduce emissions and improve the quality of compost, but they resulted in an increased composting time. Keeping in view the above points, the current study aimed to reduce the composting time and gas emissions along with improving the nutritional value of compost using FeSO4 as an additive to cattle manure and corn straw composting. Seven treatments were established, including control (CK) without FeSO4 and six levels of FeSO4 (0.25%, 0.50%, 1%, 2%, 4%, 8%). The results revealed that FeSO4 reduced the CH4 (36.1–36.7%), H2S (10.7–34.5%), N2O (17.2–48.5%), and NH3 (18.3–69.0%) emissions compared to CK. In addition, the total N (8.4–40.0%) content in compost products was also improved. The study showed that a higher dose of applied FeSO4 can significantly reduce emissions, but it reduces the temperature at the start of composting resulting in an increase in the composting time, while the lower dose (0.5–1%) also has the capability to reduce the emissions compared with the control without negatively affecting the temperature rise. The study concludes that using 0.5–1% of FeSO4 can effectively utilize its inhibitory action of decomposition that mitigates gas emissions and prepares an N-enriched compost. [ABSTRACT FROM AUTHOR]

In this work, zinc nanoparticles were prepared using the low-temperature plasma method at different times 3 min, 5 min, 7 min, 9 min, where the initial reactions of zinc lead to the formation of nanoparticles. The metal interacts with the ionized plasma under different conditions and may turn into an oxide such as exposing the sample to air and raising the temperature of the solution a few degrees as a result of high voltage and within a certain range. The atmospheric pressure plasma system acts as the cathode, while the zinc metal strip acts as the anode. A series of techniques were used, including the use of X-ray diffraction (XRD), ultraviolet-visible spectroscopy and scanning electron microscopy (FESEM). The X-ray diffraction results showed that the samples have polycrystalline structures with hexagonal and cubic structures with a time difference, and the X-ray diffraction results showed the conversion of zinc particles into zinc oxides. FESEM images reveal particle size and shape. The ZnO nanoparticles prepared by the mentioned method seem to form different nanoshapes such as starfish and mushroom nanoparticles. The UV-visible results showed that the samples had an energy gap of about 3.4 eV at a time of 3 min, and this value decreases with increasing reaction time. The appearance of zinc oxides increases gradually with the passage of time. These results provide credibility for the fabrication of ZnO nanostructures for use in future gas sensing applications, despite the inhomogeneity of particle size among ZnO particles, the sensor was also fabricated to detect nitrogen gas (NH3) with different concentrations (17.25 ppm, 46.38 ppm, 78.58 ppm). at room temperature. The ZnO sample showed the highest sensitivity (88.1%) at 7 min. The sensitivity showed different results and increased with reaction time and gas concentration. However, response and recovery time are moderate and decrease as reaction time increases. [ABSTRACT FROM AUTHOR]

The present study examined the long–term characteristics and relationship of atmospheric ammonia (NH3) with other trace gases (NO, NO2, SO2 and CO) at highly polluted urban agglomeration of Delhi, India. Measurements of ambient trace gases (NH3, NO, NO2, SO2, and CO) and meteorology were recorded at the observational site of Delhi from 2011–2022. Overall mean mixing ratios of ambient NH3, NO, NO2, SO2 and CO were 18.9 ± 5.0 ppb, 19.9 ± 4.8 ppb, 19.1 ± 5.3 ppb, 2.15 ± 0.38 ppb, and 1.47 ± 0.42 ppm, respectively during 2011—2022. During study, a significant diurnal and seasonal variation in mixing ratios of NH3, NO, NO2, and CO were observed except SO2 mixing ratio. During all the seasons, the mixing ratios of trace gases were observed higher during nighttime and lower during daytime. Correlation analysis reveals that the higher loading of NO, NO2 and CO influenced the mixing ratio of NH3 at the study site of Delhi. [ABSTRACT FROM AUTHOR]

The Air quality in university dormitories influences the learning efficiency and health of students. This study aims to evaluate the degree of influencing factors on NH3 concentration in non-newly constructed university dormitories. On-site monitoring was conducted in 136 dormitories between winter in 2021 and summer in 2022 in Shanghai. Five factors, including indoor temperature, indoor humidity, room ventilation, dormitory toilet, and cooking conditions, were identified as objects of the study. A typical student dormitory, consisting of a toilet, a storage room and a main room, was chosen to conduct orthogonal experiments. Results are as follows: The average NH3 concentration in dormitories was 0.59 mg/m3. 48% of the concentration levels exceeded the limits (0.20 mg/m3) specified in the Standards for indoor air quality (GB/T18883-2022). The range sizes of indoor temperature, indoor humidity, room ventilation, toilet, and cooking conditions were 0.01, 0.74, 1.01, 0.05, and 0.52 respectively, and the respective square sum of deviations were 0.000, 0.274, 0.510, 0.001, and 0.135. Consequently, the order of impact on NH3 concentration ranks as follows: room ventilation > indoor humidity > cooking conditions > toilet > indoor temperature. The optimal environmental conditions for achieving the lowest NH3 concentration in dormitory are found to be: ventilation (with fully open windows), low temperature (18 °C), low humidity (50%), absent cooking, and no usage of the toilet. These findings can trigger attention to NH3 pollution in dormitories, leading to more effective advice for controlling NH3 concentration in dormitories of non-newly constructed university and reducing its effects on students' health. [ABSTRACT FROM AUTHOR]

The room temperature gas sensor has attracted sufficient attention due to the fact that low-power products are more suitable for practical environments. However, developing gas sensors with low detection limits remains challenging. In this paper, a room-temperature sensor was prepared by in situ growth of WO 3 nanospheres on SnO 2 inverse opal (IO) by aerosol assisted chemical vapor deposition (AACVD) method, detecting ppb level of ammonia. The WO 3 nanospheres are directly fabricated on IO, and their elemental composition, morphology and structure is characterized using XRD, SEM and TEM. The results show that WO 3 nanospheres have been prepared on SnO 2 IO successfully. It showes that the WO 3 /SnO 2 (WS) type sensor has a detection limit as low as 1 ppb at room temperature from the gas sensitivity data. In addition, the sensor's response value to 100 ppm NH 3 reached 65 %. Its excellent sensing performance depends on the distinctive morphology features of WO 3 and SnO 2. The hierarchical characteristic effectively enhances the sensing performance for NH 3. Consequently, this presents a feasible solution for fabricating the room temperature NH 3 sensor. [ABSTRACT FROM AUTHOR]

This study introduces an innovative approach for preparing gas sensors involving the formation of metal oxides from metal–organic framework materials via a two-step calcination process. A gas-sensitive material capable of detecting NH 3 at a concentration of 11 ppb at room temperature was developed using a simple and facile experimental method. Compared with materials produced in previous studies by one-step calcination, the C-doped ZnO developed in this study had a dispersed cubic porous morphology with a higher specific surface area and smaller pore size. During two-step calcination, urea acts as a structure-directing agent and increases the gas adsorption capacity of the final material. Additionally, the incorporation of urea slightly reduced the material's band gap. Further examinations confirmed the material's exceptional selectivity and long-term stability in detecting NH 3 , and response tests at 59 %, 75 %, and 85 % relative humidity indicated its tolerance to high-humidity environments. These outstanding characteristics suggest that the proposed fabrication method can produce metal-oxide materials with substantially enhanced gas-sensing performance. [Display omitted] [ABSTRACT FROM AUTHOR]

Ammonia (NH3) gas is prevalent in industrial production as a health hazardous gas. Consequently, it is essential to develop a straightforward, reliable, and stable NH3 sensor capable of operating at room temperature. This paper presents an innovative approach to modifying SnO2 colloidal quantum dots (CQDs) on the surface of Ti3C2Tx MXene to form a heterojunction, which introduces a significant number of adsorption sites and enhances the response of the sensor. Zero-dimensional (0D) SnO2 quantum dots and two-dimensional (2D) Ti3C2Tx MXene were prepared by solvothermal and in situ etching methods, respectively. The impact of the mass ratio between two materials on the performance was assessed. The sensor based on 12 wt% Ti3C2Tx MXene/SnO2 composites demonstrates excellent performance in terms of sensitivity and response/recovery speed. Upon exposure to 50 ppm NH3, the frequency shift in the sensor is −1140 Hz, which is 5.6 times larger than that of pure Ti3C2Tx MXene and 2.8 times higher than that of SnO2 CQDs. The response/recovery time of the sensor for 10 ppm NH3 was 36/54 s, respectively. The sensor exhibited a theoretical detection limit of 73 ppb and good repeatability. Furthermore, a stable sensing performance can be maintained after 30 days. The enhanced sensor performance can be attributed to the abundant active sites provided by the accumulation/depletion layer in the Ti3C2Tx/SnO2 heterojunction, which facilitates the adsorption of oxygen molecules. This work promotes the gas sensing application of MXenes and provides a way to improve gas sensing performance. [ABSTRACT FROM AUTHOR]

In this study, delay line surface acoustic wave devices were prepared using a 128° Y-cut LiNbO3 piezoelectric substrate. Pure MoS2 and composite materials of MoS2 and SiO2 with various morphologies were sprayed to form sensitive layers. By adjusting the amount of NH4OH catalyst in the precursors, the particle sizes of SiO2 nanospheres were successfully controlled at 70, 200, and 300 nm by the sol-gel method. SiO2 nanospheres were then added to the precursor for preparing rosette-shaped MoS2, and nanocomposites were synthesized by the hydrothermal method. As a result, two types of composite material were obtained, namely, the S-M structure and the M-S structure. As ammonia gas sensors, the results showed that all the sensors exhibited negative frequency shifts as the NH3 gas concentration increased. Surface area and pore size distribution analyzer (BET) analysis showed that the highest specific surface area of 115.57 m²/g occurred on the S-M structural composite material. The sensor using the S-M structural composite material has a sensitivity of 1932 Hz/ppm to NH3 gas. The sensing linearity R-squared value is approximately 0.99, with continuous dynamic sensing at NH3 gas concentrations of 5-50 ppm. Finally, we revealed that decorating MoS2 with SiO2 nanospheres can improve the adsorption of ammonia molecules and significantly enhance sensitivity. [ABSTRACT FROM AUTHOR]

Bi2S3/Ti3C2Tx nanomaterials were successfully prepared through a simple hydrothermal method. Various methods were used for their characterization, including XRD, XPS, SEM, EDS, and BET, along with testing their gas-sensing properties. The results showed that the response value to 100 ppm ammonia at room temperature reached 107%, which was 14.1 times higher than that of pure few-layer MXene. After undergoing anti-humidity interference testing, we observed that Bi2S3/Ti3C2Tx exhibited a higher response value in real-time monitoring of ammonia as humidity increased. Specifically, under 90% humidity conditions, its response value reached 1.32 times that of normal humidity conditions. This exceptional moisture resistance ensures that the sensor can maintain stability, and even exhibit superior performance, in harsh environments. Therefore, it possesses excellent selectivity, high-moisture-resistance, and long-term stability, making it significant in the field of medical and health monitoring. [ABSTRACT FROM AUTHOR]

With the deep integration of industries such as the Internet of Things (Iot), big data, and artificial intelligence, sensors are becoming more and more interconnected and intelligent, which also poses a higher challenge to the development of gas sensors with excellent gas sensitive performance. WO 3 -based gas sensors are widely used in the detection of H 2 S and NH 3 gases because of their unique electrical characteristics. This paper reviews the progress of WO 3 -based chemoresistive gas sensors for the difficult-to-remove reducing gases H 2 S and NH 3. First, the sensing mechanism of pure-phase WO 3 as well as the enhancement of WO 3 sensing through modification strategies, including the construction of heterojunctions, the electronic and chemical sensitization mechanisms of noble metal modifications, the protonation/deprotonation process of polyaniline (PANI), and photoexcitation, are discussed. In addition, the application of WO 3 gas sensors using different nanostructures (such as quantum dots, nanoparticles, nanowires, nanotubes, nanofibers, and flowers) for the detection of H 2 S and NH 3 gases is summarized in detail. Although pure-phase WO 3 can effectively detect toxic and hazardous gases, it still has the disadvantages of low sensitivity, poor selectivity and high operating temperature. Metal oxide semiconductor (MOS) compounding, ion doping, noble metal modification, organic conductive polymer compounding, carbon-based material loading, transition metal-disulfide compounds (TMDCs) modification, and light can effectively improve the gas-sensitive properties. Finally, the challenges and prospects of WO 3 -based H 2 S and NH 3 gas sensors are also thoroughly analyzed and discussed. [Display omitted] [ABSTRACT FROM AUTHOR]

Greenhouse gas and NH3 emissions are exacerbated by the inappropriate timing and excessive application of nitrogen (N) fertilizers in wheat cultivation in China. In this study, the impacts on N2O, CO2, and NH3 emissions of a delayed and reduced N application regime on the Huang-Huai-Hai Plain were investigated. The treatments comprised the control (N0), conventional N at 270 kg N ha−1 (N270) and optimized N application of 180 kg N ha−1 (N180), N180 + biochar at 7.5 t ha−1 (N180B7.5), N180 + biochar at 15 t ha−1 (N180B15), N180 + DMPP (a nitrification inhibitor; N180D), N180D + biochar at 7.5 t ha−1 (N180DB7.5), and N180D + biochar at 15 t ha−1 (N180DB15). Reduced N application (N180) lowered N2O and NH3 emissions. Biochar application resulted in a 4–25% and 12–16% increase in N2O and NH3 emissions, respectively. Application of DMPP significantly decreased N2O emissions by 32% while concurrently inducing a 9% increase in NH3 emissions. Co-application of DMPP and biochar significantly reduced the activity of nitrification enzymes (HAD, NOO), resulting in a reduction of 37–38% in N2O emissions and 13–14% in NH3 emissions. No significant differences in CO2 emissions were observed among the various N treatments except the N0 treatment. Application of DMPP alone did not significantly affect grain yield. However, biochar, in combination with DMPP, effectively increases grain yield. The findings suggest that the N180DB15 treatment has the potential to reduce emissions of N2O and NH3 while concurrently enhancing soil fertility (pH, SOC) and wheat yield. [ABSTRACT FROM AUTHOR]

Bi2S3/Ti3C2Tx nanomaterials were successfully prepared through a simple hydrothermal method. Various methods were used for their characterization, including XRD, XPS, SEM, EDS, and BET, along with testing their gas-sensing properties. The results showed that the response value to 100 ppm ammonia at room temperature reached 107%, which was 14.1 times higher than that of pure few-layer MXene. After undergoing anti-humidity interference testing, we observed that Bi2S3/Ti3C2Tx exhibited a higher response value in real-time monitoring of ammonia as humidity increased. Specifically, under 90% humidity conditions, its response value reached 1.32 times that of normal humidity conditions. This exceptional moisture resistance ensures that the sensor can maintain stability, and even exhibit superior performance, in harsh environments. Therefore, it possesses excellent selectivity, high-moisture-resistance, and long-term stability, making it significant in the field of medical and health monitoring. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) has received considerable attention as a major reduced nitrogen. However, accurate estimates of the deposition amount are difficult due to its complex behavior characterized by bidirectional exchange between the atmosphere and the surface. We observed the vertical profile of NH3 concentration in a deciduous forest in Japan for 1 year to further advance the studies on NH3 bidirectional exchange in Asia, especially focusing on the process near the forest floor. The observation period lasted from September 29, 2020, to September 28, 2021, including leafy and leafless periods. Using the denuder sampling technique, we measured NH3 concentration in the forest at three heights (above the forest canopy, 30 m, and near the forest floor, 2 m and 0.2 m). NH3 concentrations tended to be highest at the top of the canopy (30 m). Focusing on the concentration near the forest floor, the concentrations at 0.2 m were frequently higher than those at 2 m regardless of the leafy and leafless period, thus suggesting NH3 emissions from the forest floor. NH3 concentration near the forest floor showed strong positive correlations with air temperature during the leafy period. The NH3 emissions from the forest floor during the leafy period were possibly due to the decomposition of leaf litter with increased air temperature. The decrease in leaf area index might induced the increase in NH3 concentration and emission. NH3 emission during the leafless period was also possibly dependent on the state of the deposition surface, apart from air temperature, relative humidity, and leaf area index. [ABSTRACT FROM AUTHOR]