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The application of livestock slurry in soils can lead to nitrogen (N) losses through ammonia (NH3) emission or nitrate (NO3−) leaching. Oxidized biochar has great potential to mitigate N losses due to its strong adsorption capacity; however, the effects of oxidized biochar in different soils treated with slurry are currently unclear. Here, we investigated the effect of untreated and oxidized biochar (applied at a rate of 50 kg C m−3 slurry) on reducing N losses in a laboratory experiment with three different soils (loamy sand, sandy loam, loam) amended with cattle slurry at an application rate of 73 kg N ha−1. Oxidized biochar reduced NH3 emissions by 64–75% in all soils, whereas untreated biochar reduced NH3 emissions by 61% only in the loamy sand. Oxidized biochar significantly reduced the NO3− content in the soil solution of the loamy sand in the early phase of the incubation and led to a significantly higher NO3− concentration in the same soil compared with the slurry-only treatment at the end of the experiment, indicating a significant increase in NO3− retention in this organic C–poor soil. We conclude that oxidized biochar can reduce N losses, both in the form of NH3 emission and NO3− leaching, from cattle slurry applied to soil, particularly in soil with soil organic carbon content

Nitrogen (N) losses during fertilization with livestock slurry, mainly in the form of ammonia (NH

The optical crosstalk effect in Multi-Pixel Photon Counters (MPPC) is unnecessary parasitic effects. The mechanism leading to the non-uniform spatial distribution of the prompt optical crosstalk in MPPCs was investigated in detail herein. The experimental results showed that the optical crosstalk probability (Pct) in MPPCs without optical isolation trenches was clearly non-uniform within the Geiger-mode avalanche photodiode (G-APD) cell. However, the spatial distribution uniformity of Pct in G-APD cells was improved significantly in an MPPC containing optical isolation trenches. The different propagation distances of crosstalk photons emitted from different positions of the source G-APD cell to the nearest neighboring G-APD cell along a straight line, were the main reason for the non-uniform spatial distribution of Pct in the MPPC. According to the experimental results, it can also be inferred that the emission of crosstalk photons is spatially localized during a G-APD cell’s avalanche event, and majority crosstalk photons are emitted during the early stage of the avalanche.

Emissions of agricultural machines during tillage processes played an important role in severe seasonal pollution events in agricultural areas in China and cannot be ignored. In this study, the CO, NOX, HC and PM2.5 emissions of agricultural machines during real-world tillage processes were tested using a portable emission measurement system (PEMS), and their fuel-based and tillage area-based emission factors were calculated. The CO, NOX, HC and PM2.5 emissions were influenced by emission standards, engine rated power, tillage processes and crops. Only the CO, HC and PM2.5 fuel-based emission factors were reduced from China 0 to China II. For China III agricultural machines, the fuel-based emission factors were higher during plowing and tilling than during harvesting. The tillage area-based CO, NOX, HC and PM2.5 emission factors of corn tillage process were 11.85 ± 8.30, 53.21 ± 48.80, 3.46 ± 3.14 and 1.64 ± 1.33 kg/km2, respectively. The tillage area-based CO, NOX, HC and PM2.5 emission factors of wheat tillage process were 19.69 ± 21.50, 79.98 ± 63.22, 3.90 ± 2.96 and 1.61 ± 2.43 kg/km2, respectively. The tillage area-based emission factors of China III agricultural machines during plowing and tilling were higher than those during harvesting. The fuel consumption per unit tillage area can be used to provide a reference for the interconversion of the two emission factors in future studies. By comparing the fuel-based emission factors in this study with those in the Guidelines and other studies, we observed that the CO, HC and PM2.5 emissions of agricultural machines with corresponding emission standards may be overestimated and the NOX emissions may be underestimated in areas where wheat and corn are mainly grown. Moreover, the pollutant emissions of agricultural machines were regionally different. These results could help elucidate the pollution contribution of agricultural machines in China.

Prostate cancer (PCa) is associated with a high incidence and metastasis rate globally, resulting in an unsatisfactory prognosis and a huge economic burden due to the current deficient of therapeutic strategies. As the most abundant component of Cortex Mori, Sanggenon C (SC) is well known to possess bioactivities in tumors, but its mechanism is poorly understood. Consequently, we attempted to investigate whether SC could modulate circular RNA(s) levels and hence anti-PCa development. We found that SC dramatically promoted cell apoptosis and induced G0/G1 phase arrest in PCa cell lines via the circHMGCS1-miR-205-5p-ErBB3 axis. In brief, circHMGCS1 is highly expressed in PCa and is positively correlated with the degree of malignancy. Over-expression of circHMGCS1 is not only associated with the proliferation of PCa cells but also blocks SC-induced pro-apoptotic effects. As a verified sponge of circHMGCS1, miR-205-5p is down-regulated in PCa tumors, which negatively regulates PCa cell proliferation by modulating ErBB3 expression. After miR-205-5p mimics or inhibitors were used to transfect PCa cells, the effects of circHMGCS1 OE and SC on PCa cells were completely diminished. Similar to miR-205-5p inhibitors, siErBB3 could oppose SC-triggered pro-apoptotic effects on PCa cells. All these results were confirmed in vivo. Together, SC exerts its anti-tumor effects on PCa by inhibiting circHMGCS1 expression and results in the latter losing the ability to sponge miR-205-5p. Subsequently, unfettered miR-205-5p could mostly down-regulate ErBB3 expression by binding to the 5'UTR of ErBB3 mRNA, which eventually resulted in PCa cell cycle arrest and pro-apoptosis.

A rapid reaction occurs near the exhaust nozzle when vehicle emissions contact the air. Twenty diesel vehicles were studied using a new multipoint sampling system that is suitable for studying the exhaust plume near the exhaust nozzle. The variation characteristics of fine particle matter (PM2.5) and its components in diesel vehicle exhaust plumes were analyzed. The PM2.5 emissions gradually increased with increasing distance from the nozzle in the plume. Elemental carbon emissions remained basically unchanged, organic carbon and total carbon (TC) increased with increasing distance. The concentrations of SO42-, NO3- and NH4+ (SNA) directly emitted by the vehicles were very low but increased rapidly in the exhaust plume. The selective catalytic reduction (SCR) reduced 42.7% TC, 40% NO3- emissions, but increased 104% SO42- and 36% NH4+ emissions, respectively. In summary, the SCR reduced 29% primary PM2.5 emissions for the tested diesel vehicles. The NH4NO3 particle formation maybe more important in the plume, and there maybe other forms of formation of NH4+ (eg. NH4Cl). The generation of secondary organic carbon (SOC) plays a leading role in the generation of secondary PM2.5. The SCR enhanced the formation of SOC and SNA in the plume, but comprehensive analysis shows that the SCR more enhanced the SNA formation in the plume, which is mainly new particles formation process. The inconsistency between secondary organic aerosol (SOA) and primary organic aerosol definitions is one of the important reasons for the difference between SOA simulation and observation.

Mutation is the basis of phenotypic changes and serves as the source of natural selection. The development of limbs has been the milestone in vertebrate evolution. Several limb and bone-related genes were verified experimentally, but other indirect and regulatory factors of limb development remained untested, especially very few cases were observed in natural environment. We report a naturally born serpentized pig without hindlimbs. Whole genome sequencing followed by comparative genomic analysis revealed multiple interesting patterns on the handicapped pig-specific mutations. Although the bone-related genes are not directly subjected to mutations, other regulatory factors such as the RNA deaminase genes Adar are damaged in the handicapped pig, leading to the abolished A-to-I deamination in many functional, conserved genes as well as the bone-related genes. This is a precious case that the limbless phenotype is observed in naturally born non-model organisms. Our study broadened the generality of the limbless phenotype across mammals and extended the regulation of hindlimb development to other non-bone-related genes. Our knowledge of limb and bone-related mutations and regulation would also contribute to human genetics.

Purpose Compost has great potential for use in sustainable agriculture. Stoichiometric relationships between C, N and P play an important role in soil biogeochemical processes. The aim of this study was to quantify greenhouse gas (GHG) emissions, soil nutrient retention and leaching, aboveground biomass and crop yield at different soil C:N:P ratios. Methods The lysimeter experiment included six treatments: (1) without fertilization and seeding (bare), (2) common P fertilization (control), (3) P fertilization at twice the common level, (4) compost addition of 40 t ha-1 and common P fertilization, (5) compost addition of 40 t ha-1 and P fertilization at twice the common level, and (6) compost addition of 80 t ha-1 and common P fertilization. Treatments 2-6 were all fertilized at the same N level. Results Compost application significantly increased aboveground biomass and grain yield, particularly in the double compost treatment, where the variability between replicates was particularly low. However, the effect of compost application on GHG emissions was insignificant. Addition of 80 t ha-1 of compost increased dissolved organic carbon (DOC), compared to the control, but did not lead to a significant increase in DOC, N and P leaching losses. In contrast, bare soil resulted in significant leaching losses of DOC and nitrate (NO3–) compared to plant-covered treatments. Conclusion We conclude that combined compost and N fertilizer application is a suitable management option for increasing crop yield and reducing its variability, as it does not lead to increased GHG emissions and leaching losses of NO3– and P.

State-of-art non-invasive diagnosis processes for bladder cancer (BLCA) harbour shortcomings such as low sensitivity and specificity, unable to distinguish between high- (HG) and low-grade (LG) tumours, as well as inability to differentiate muscle-invasive bladder cancer (MIBC) and non-muscle-invasive bladder cancer (NMIBC). This study investigates a comprehensive characterization of the entire DNA methylation (DNAm) landscape of BLCA to determine the relevant biomarkers for the non-invasive diagnosis of BLCA.A total of 304 samples from 224 donors were enrolled in this multi-centre, prospective cohort study. BLCA-specific DNAm signature discovery was carried out with genome-wide bisulfite sequencing in 32 tumour tissues and 12 normal urine samples. A targeted sequencing assay for BLCA-specific DNAm signatures was developed to categorize tumour tissue against normal urine, or MIBC against NMIBC. Independent validation was performed with targeted sequencing of 259 urine samples in a double-blinded manner to determine the clinical diagnosis and prognosis value of DNAm-based classification models. Functions of genomic region harbouring BLCA-specific DNAm signature were validated with biological assays. Concordances of pathology to urine tumour DNA (circulating tumour DNA [ctDNA]) methylation, genomic mutations or other state-of-the-art diagnosis methods were measured.Genome-wide DNAm profile could accurately classify LG tumour from HG tumour (LG NMIBC vs. HG NMIBC: p = .038; LG NMIBC vs. HG MIBC, p = .00032; HG NMIBC vs. HG MIBC: p = .82; Student's t-test). Overall, the DNAm profile distinguishes MIBC from NMIBC and normal urine. Targeted-sequencing-based DNAm signature classifiers accurately classify LG NMIBC tissues from HG MIBC and could detect tumours in urine at a limit of detection of less than .5%. In tumour tissues, DNAm accurately classifies pathology, thus outperforming genomic mutation or RNA expression profiles. In the independent validation cohort, pre-surgery urine ctDNA methylation outperforms fluorescence in situ hybridization (FISH) assay to detect HG BLCA (n = 54) with 100% sensitivity (95% CI: 82.5%-100%) and LG BLCA (n = 26) with 62% sensitivity (95% CI: 51.3%-72.7%), both at 100% specificity (non-BLCA: n = 72; 95% CI: 84.1%-100%). Pre-surgery urine ctDNA methylation signature correlates with pathology and predicts recurrence and metastasis. Post-surgery urine ctDNA methylation (n = 61) accurately predicts recurrence-free survival within 180 days, with 100% accuracy.With the discovery of BLCA-specific DNAm signatures, targeted sequencing of ctDNA methylation outperforms FISH and DNA mutation to detect tumours, predict recurrence and make prognoses.

The optical crosstalk effect in Multi-Pixel Photon Counters (MPPC) is unnecessary parasitic effects. The mechanism leading to the non-uniform spatial distribution of the prompt optical crosstalk in MPPCs was investigated in detail herein. The experimental results showed that the optical crosstalk probability (Pct) in MPPCs without optical isolation trenches was clearly non-uniform within the Geiger-mode avalanche photodiode (G-APD) cell. However, the spatial distribution uniformity of Pct in G-APD cells was improved significantly in an MPPC containing optical isolation trenches. The different propagation distances of crosstalk photons emitted from different positions of the source G-APD cell to the nearest neighboring G-APD cell along a straight line, were the main reason for the non-uniform spatial distribution of Pct in the MPPC. According to the experimental results, it can also be inferred that the emission of crosstalk photons is spatially localized during a G-APD cell’s avalanche event, and majority crosstalk photons are emitted during the early stage of the avalanche.

Background Wound healing has become a worldwide healthcare issue. Attempts in the area focus on developing patches with the capabilities of avoiding wound infection, promoting tissue remolding, and reporting treatment status that are of great value for wound treatment. Results In this paper, we present a novel inverse opal film (IOF) patch based on a photo-crosslinking fish gelatin hydrogel with the desired features for wound healing and dynamic monitoring. The film with vibrant structure colors was constructed by using the mixture of fish gelatin methacryloyl, chitosan, and polyacrylic acid (PAA) to replicate colloidal crystal templates. As the structures of these natural biomolecules are well-retained during the fabrication, the resultant IOF was with brilliant biocompatibility, low immunogenicity, antibacterial property, as well as with the functions of promoting tissue growth and wound healing. In addition, the IOF presented interconnected nanopores and high specific surface areas for vascular endothelial growth factor loading, which could further improve its angiogenesis capability. More attractively, as the pH-responsive PAA was incorporated, the IOF patch could report the wound healing status through its real-time structural colors or reflectance spectra. Conclusions These features implied the practical value of the multifunctional fish gelatin hydrogel IOFs in clinical wound management. Graphical Abstract

Predicting spatial explicit information of soil nutrients is critical for sustainable soil management and food security under climate change and human disturbance in agricultural land. Digital soil mapping (DSM) techniques can utilize soil-landscape information from remote sensing data to predict the spatial pattern of soil nutrients, and it is important to explore the effects of remote sensing data types on DSM. This research utilized Landsat 8 (LT), Sentinel 2 (ST), and WorldView-2 (WV) remote sensing data and employed partial least squares regression (PLSR), random forest (RF), and support vector machine (SVM) algorithms to characterize the spatial pattern of soil total nitrogen (TN) in smallholder farm settings in Yellow River Basin, China. The overall relationships between TN and spectral indices from LT and ST were stronger than those from WV. Multiple red edge band-based spectral indices from ST and WV were relevant variables for TN, while there were no red band-based spectral indices from ST and WV identified as relevant variables for TN. Soil moisture and vegetation were major driving forces of soil TN spatial distribution in this area. The research also concluded that farmlands of crop rotation had relatively higher TN concentration compared with farmlands of monoculture. The soil prediction models based on WV achieved relatively lower model performance compared with those based on ST and LT. The effects of remote sensing data spectral resolution and spectral range on enhancing soil prediction model performance are higher than the effects of remote sensing data spatial resolution. Soil prediction models based on ST can provide location-specific soil maps, achieve fair model performance, and have low cost. This research suggests DSM research utilizing ST has relatively high prediction accuracy, and can produce soil maps that are fit for the spatial explicit soil management for smallholder farms.

Detailed emission characterization of semivolatile/intermediate-volatility organic compounds (S/IVOCs) originating from nonroad construction machines (NRCMs) remains lacking in China. Twenty-one NRCMs were evaluated with a portable emission measurement system in the working process. Gas phase S/IVOCs were collected by Tenax TA tubes and analyzed via thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). Particle phase S/IVOCs were collected by quartz filters and analyzed via GC-MS. The average emission factors (EFs) for fuel-based total (gas + particle phase) IVOCs and SVOCs of the assessed NRCMs were 221.45 ± 194.60 and 11.68 ± 10.67 mg/kg fuel, respectively. Compared to excavators, the average IVOC and SVOC EFs of loaders were 1.32 and 1.55 times higher, respectively. Compared to the working mode, the average IVOC EFs under the moving mode (only moving forward or backward) were 1.28 times higher. The IVOC and SVOC EFs for excavators decreased by 69.06% and 38.37%, respectively, from China II to China III. These results demonstrate the effectiveness of emission control regulations. In regard to individual NRCMs, excavators and loaders were affected differently by emission standards. The volatility distribution demonstrated that IVOCs and SVOCs were dominated by gas- and particle-phase compounds, respectively. The mode of operation also affected S/IVOC gas-particle partitioning. Combined with previous studies, the mechanical type significantly affected the volatility distribution of IVOCs. IVOCs from higher volatile fuels are more distributed in the high-volatility interval. The total secondary organic aerosol (SOA) production potential was 104.36 ± 79.67 mg/kg fuel, which originated from VOCs (19.98%), IVOCs (73.87%), and SVOCs (6.15%). IVOCs were a larger SOA precursor than VOCs and SVOCs. In addition, normal (n-) alkanes were suitably correlated with IVOCs, which may represent a backup solution to quantify IVOC EFs. This work provides experimental data support for the refinement of the emission characteristics and emission inventories of S/IVOCs originating from NRCMs.

In-depth exploration of the potential links between instantaneous black carbon (BC) emissions and driving parameters from real-world diesel trucks (DTs) is a key step toward development of a highly flexible vehicle emissions estimation system. In this study, we conducted real-world measurements on 22 DTs with mainstream types and emission standards, and obtained instantaneous data of BC emissions and vehicle driving. Since vehicle specific power (VSP) is an excellent surrogate for engine load, we characterize the instantaneous BC emissions and VSP distributions, and then establish links between VSP and fuel consumption, VSP and BC emission rates, VSP and BC emission factors (EFs), respectively. We find that BC emission rates of China V light-duty DTs installed with diesel particulate filter (DPF) are significantly lower (2 to 3 orders of magnitude) than those with China III and China IV. Frequent acceleration and deceleration of vehicles maybe the main reason leads to high BC emissions. The distribution of VSP is mainly concentrated in the ranges of -30 to 35 kW/t in the scope of this study. We find that VSP and BC EFs did not show a consistent pattern for all tested DTs, and BC EFs present obvious fluctuations with the VSP variation. The average fuel-based BC EFs vary by factors of 2.27-8.25 from the lowest to highest EFs. Through a fitting of the third-order polynomial function, we finally quantify and provide fitting formulas of BC EFs and VSP under more detailed categorization. Our results can provide important data support for accurate quantification of BC EFs, and even emission inventory calculations.

Sub-micron faculae (light spots) at the single-photon level have important applications in many fields. This report demonstrates a method for measuring facula size at the sub-micron single-photon level indirectly. The developed method utilizes Silicon Photomultipliers (SiPMs) as the single-photon response detectors, combined with a nano-positioning stage. The approach involves one- or two-dimensional space scanning and a deconvolution operation, which enable evaluations of the size and spatial distribution of focused facula in a single-photon-level pulsed laser. The results indicate that the average full width at half maximum of the faculae is about 0.66 µm, which is close to the nominal resolution of the objective lens of the microscope (0.42 µm). The proposed method has two key advantages: (1) it can measure sub-micron facula at the single-photon level, and (2) the sub-micron facula can easily be aligned with the detector because the array area of the avalanche photodiode cells in SiPM is usually larger than one square millimeter, and there is no need to put an optical slit, knife edge, or pinhole in front of the detector. The method described herein is applicable in weak light facula detection related fields.

Intratumor heterogeneity (ITH) of bladder cancer (BLCA) facilitates therapy resistance and immune evasion to affect clinical prognosis directly. However, the molecular and cellular mechanism generating ITH in BLCA remains elusive. Here we show that a TM4SF1-positive cancer subpopulation (TPCS) drives ITH diversification in BLCA. By extensive profiling of the epigenome and transcriptome of BLCA from 79 donors across all stages, we elucidated the evolution trajectories of luminal and basal BLCA. TPCS emerges from the basal trajectory and shows extensive transcriptional plasticity with a distinct epigenomic landscape. Clinically, TPCS were enriched in advanced stage patients and associated with poor prognosis. Our results showed how cancer adapts to its environment by adopting a stem cell-like epigenomic landscape.

Although ion exchange resins (IERs) have been extensively adopted in water treatment, there are no reports on the application thereof for synthesizing antibacterial materials against pathogenic bacteria. The present study is the first in which the ion exchange characteristic of IERs was utilized to introduce silver ions that possess efficient antibacterial properties. The resulting antibacterial materials were incorporated into polylactic acid (PLA) and/or polybutylene adipate terephthalate (PBAT) to prepare antibacterial membranes. XPS spectra revealed the occurrence of in-situ reduction of silver ions to metallic silver, which was preferable since the stability of silver in the materials was improved. EDS mapping analysis indicated that the distribution of silver was consistent with the distribution of sulfur in the membranes, verifying the ion exchange methodology proposed in the present study. To investigate the antibacterial performance of the prepared membranes, zone of inhibition tests and bacteria-killing tests were performed. The results revealed that neither bare polymeric membranes of PLA and PBAT nor IER-incorporated polymeric membranes exhibited noticeable antibacterial activities. In comparison, the antibacterial membranes demonstrated effective and sustainable antibacterial activities against pathogenic bacteria Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The prepared antibacterial membranes exhibited potential in food-related applications such as food packaging to delay food spoilage due to microbial growth.

Non-road construction equipment (NRCE) has become a crucial contributor to urban air pollution. However, the current research on NRCE is still in its infancy, and the understanding of its pollutant emissions is not yet clear. In this study, multi-pollutant (CO, HC, NOx, PM

The spray atomization of an injector significantly influences the performance and working life span of a bipropellant thruster of a spacecraft. Deep space exploration requires the thruster to be able to operate reliably at a low temperature range from −40 °C to 0 °C, so the effect of low temperature conditions on the atomization characteristics of injector spray is motivated to be comprehensively investigated. To study the swirl atomization characteristics of MMH (methylhydrazine), which is more difficult to atomize than NTO (nitrogen tetroxide), numerical simulations were conducted, employing the methods of VOF (volume of fluid) and LES (large eddy simulation) under low temperature conditions. The physical model with a nozzle size of 0.5 mm and boundary conditions with a velocity inlet of 3.89 m/s both follow the actual operation of thrusters. The development of spray atomization at low temperatures was observed through parametric comparisons, such as spray velocity, liquid total surface area, droplet particle size distribution, spray cone angle and breakup distance. When the temperature decreased from 20 °C to −40 °C at the same condition of flowrate inlet, those atomization characteristics of MMH propellant vary following these rules: the spray ejection velocity of MMH is significantly reduced by 7.7%, and gas-liquid disturbance sequentially decreases; the liquid film development is more stable, with a negative influence on atomization quality, causing difficulties for primary and secondary breakup, so the total surface area of droplets also decreases by 6.4%; the spatial distribution characteristics, spray cone angle and breakup distance vary less than 5%. Therefore, the low temperature condition can directly lower the combustion efficiency of thrusters with obvious performance degradation, but there are no significant changes in the propellant mixing and liquid film cooling. It is concluded that the bipropellant thruster can reliably work at low temperatures around −40 °C for deep space probe operation.

The rapid reproduction of foodborne bacteria in food packaging threatens the health of consumers, the massive use and waste of packaging also causes serious environmental pollution. In this study, novel biodegradable antibacterial membranes based on silver-modified carboxymethyl chitosan (Ag-CMCS) were prepared. Polylactic acid (PLA) and polybutylene adipate-co-terephthalate (PBAT) were used as the base membrane materials. Characterization of the prepared membranes was performed by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), atomic force microscope (AFM), X-ray photoelectron spectroscopy (XPS), water contact angle, and so on. Especially, the silver on the surface of Ag-CMCS was proved to be metallic silver. For the first cycle of zone of inhibition test, the diameter of inhibition zone could reach up to 17 mm while the mass of silver released was negligible. The prepared antibacterial membranes could kill almost 100% of bacteria under certain conditions and inhibition zone still existed after more than 7 cycles of tests, indicating the prepared antibacterial membranes were effective. This study could provide new ideas for preparing efficient and environment-friendly antibacterial food packaging membranes.

Non-road construction equipment (NRCE) has become a vital contributor to urban air pollutants with the rapid urbanization in China. Black carbon (BC), as a key pollutant emitted from NRCE (mainly diesel-fueled), has attracted considerable concerns due to adverse impacts on climate change, visibility, and human health. However, the understanding of its emissions is still unclear based on limited research results. In this study, we conducted real-world measurements on BC emissions from 12 excavators and 9 loaders to characterize the variation and quantify fuel-based emission factors (EFs) by using a synchronous platform based on PEMS (SP-PEMS). We analyzed the impacts of key factors (operation mode, emission standard, and engine rated power) on BC emission comprehensively. High BC emission in working mode may be mainly owing to the increase of fuel consumption and the deterioration of air-fuel ratio. With more stringent emission standards, BC EFs of all tested NRCE present significant decreasing trends. Interestingly, NRCE with high rated power generally exhibits lower BC emissions. Through comparison, we find BC EFs in this study are generally higher than elemental carbon (EC) EFs reported in previous studies, which will lead BC emissions from NRCE to be underestimated while EC EFs are used instead of BC EFs. Furthermore, BC EFs of NRCE with Stage III are significantly higher (1–3 orders of magnitude) than those of on-road diesel trucks with the current mainstream emission standards of China IV and China V, which reinforces the urgency and importance of controlling BC emissions from NRCE in China. Finally, we recommend BC EFs of excavators and loaders under different emission standards and operation modes, and which preliminarily fills the gap in localized BC EFs of typical NRCE to relieve the urgent needs for emission inventory calculation.

Emissions of carbonyl compounds from agricultural machines cannot be ignored. Carbonyl compounds can cause the formation of ozone (O