Laboratory Investigation of Dodecylbenzene Detection in Seawater Via Fluorometric Index of Excitation-emission Matrix Spectra.

​Oil-filled submarine cables have come to dominate the reliable delivery of electrical power today, but oil leakages still remain a challenge. This work focuses on exploring the detection of dodecylbenzene (DDB) after leakage. DDB can be dispersed as small droplets in seawater, which the diameter of DDB droplets increased from 60 nm to 200 nm with the increase of the concentration from 10 ppm to 1000 ppm. Moreover, excitation-emission matrix (EEM) spectra were employed to investigated the detection of DDB. DDB has characteristic fluorescence peaks located at λEx/λEm = 225/350 and 255/350. The FIo/w value of 50 ppm DDB was 28.869, which was significantly different from simulated seawater low as 1.3926. Contaminants such as metal ions (Cu2+, Cd2+, Zn2+) and organic matter (tetracycline) do not significantly affect the qualitative identification of DDB by EEMs. This study suggests a research basis for exploring the way for detection of DDB.

Mitigation potential of methane emissions in China's livestock sector can reach one-third by 2030 at low cost.

The mitigation of methane (CH4) emissions from livestock production is crucial to China's carbon neutrality. Here we established a high-spatiotemporal-resolution dataset of the country's livestock CH4 emissions from 1990 to 2020 using four large-scale national livestock greenhouse gas inventory surveys. We estimate CH4 emissions to be 14.1 ± 2.0 Mt in 2020 and to increase by 13% until 2030 despite CH4 intensity per kg animal protein having decreased by 55% in the past 30 years. Approximately half of the emissions come from 13% of all Chinese counties. The technical CH4 mitigation potential is projected to be 36 ± 8% (4.4-6.9 Mt CH4) in 2030, and reducing food loss and waste could mitigate an additional 1.6 Mt of CH4. Overall, most CH4 mitigation could be achieved by increasing animal productivity and coverage of lagoon storage at carbon prices below US$100 tCO2e-1, being more cost-effective than livestock nitrous oxide mitigation in China.

Experimental Study on the Improvement of Char Physicochemical Properties and Reactivity by Activation Process in CFB.

Solid carbon can be transformed into activated char with higher reactivity through the activation process in a circulating fluidized bed (CFB) to improve the Boudouard reaction. A new technology for reducing CO2, the activated-reduction technology, was proposed. In order to investigate the influence of relevant parameters (carbon dioxide addition, oxygen concentration, and O2/C) of the activation process on the physicochemical properties and reactivity of activated char, the experiments were carried out on a bench-scale CFB. The relationship between the parameters and the reactivity of activated char is explored. The result shows that compared with the raw coal, the pore structure of activated char is developed, the number of active sites increases, the degree of graphitization decreases, and higher reactivity is possessed. For the activation process, less of the O2/C and moderate oxygen concentration promote the increase in activated char reactivity, which is conducive to the reduction of CO2. The results of the correlation discussion show that the reactivity is difficult to be characterized by a single simple parameter. The reactive specific surface area (RSSA) obtained by multiplying the mesoporous specific surface area and I D3+D4/I all has a good effect on describing the reactivity.

An Exploratory Pilot Study on the Application of Radiofrequency Ablation for Atrial Fibrillation Guided by Computed Tomography-Based 3D Printing Technology.

Radiofrequency ablation (RFA) is the treatment of choice for atrial fibrillation (AF). Additionally, the utilization of 3D printing for cardiac models offers an in-depth insight into cardiac anatomy and cardiovascular diseases. The study aims to evaluate the clinical utility and outcomes of RFA following in vitro visualization of the left atrium (LA) and pulmonary vein (PV) structures via 3D printing (3DP). Between November 2017 and April 2021, patients who underwent RFA at the First Affiliated Hospital of Xinxiang Medical University were consecutively enrolled and randomly allocated into two groups: the 3DP group and the control group, in a 1:1 ratio. Computed tomography angiography (CTA) was employed to capture the morphology and diameter of the LA and PV, which facilitated the construction of a 3D entity model. Additionally, surgical procedures were simulated using the 3D model. Parameters such as the duration of the procedure, complications, and rates of RFA recurrence were meticulously documented. Statistical analysis was performed using the t-test or Mann-Whitney U test to evaluate the differences between the groups, with a P-value of less than 0.05 considered statistically significant. In this study, a total of 122 patients were included, with 53 allocated to the 3DP group and 69 to the control group. The analysis of the morphological measurements of the LA and PV taken from the workstation or direct entity measurement showed no significant difference between the two groups (P > 0.05). However, patients in the 3DP group experienced significantly shorter RFA times (97.03 ± 28.39 compared to 120.51 ± 44.76 min, t = 3.05, P = 0.003), reduced duration of radiation exposure (2.55 [interquartile range 2.01, 3.24] versus 3.20 [2.28, 3.91] min, Z = 3.23, P < 0.001), and shorter modeling times (7.68 ± 1.03 compared to 8.89 ± 1.45 min, t = 5.38, P < 0.001). 3DP technology has the potential to enhance standard RFA practices by reducing the time required for intraoperative interventions and exposure to radiation.

The influence of using different types of modified vermiculite cover on ammonia mitigation from animal slurry storage: The role of sulfuric acid.

Animal slurry storage is an important ammonia (NH3) emission source. Sulfuric acid (H2SO4)-modified vermiculite coverage is a new promising technology for controlling NH3 emission from slurry storage. However, the underlying mechanisms in controlling the mitigation effect remain unclear. Here, a series of experiments to determine the effect of H2SO4 on the modified vermiculite properties, floating persistence, and NH3 mitigation effect was conducted. Results showed that abundant H2SO4 and sulfate remained on the outer surface and in the extended inner pores of the vermiculite with acidifying H+ concentrations higher than 5 M. An initial strong instantaneous acidification of surface slurry released rich carbon dioxide bubbles, strengthening cover floating performance. An acidification in the vermiculite cover layer and a good coverage inhibition interacted, being the two leading mechanisms for mitigating NH3 during initial 40-50 days of storage. The bacterial-amoA gene dominated the conversion of NH3 to nitrous oxide after 50 days of storage. Vermiculite with 5 M H+ modification reduced the NH3 emissions by 90 % within the first month of slurry storage and achieved a 64 % mitigation efficiency throughout the 84 days period. With the development of the aerial spraying equipment such as agricultural drones, acidifying vermiculite coverage hold promise as an effective method for reducing NH3 emission while absorbing nutrients from liquid slurry storage tank or lagoon. This design should now be tested under field conditions.

Effect of polyaniline dispersibility in chitin sponge matrix controlled by hydrophilicity on microplastics adsorption.

Microplastics have become an emerging threat to global ecosystems, and their efficient removal faces with serious challenges. Herein, this study introduced different hydrophilic polyaniline (PANIs) into chitin matrix to fabricate Chitin-PANIs sponge (ChPANIs) and investigated the relationship between PANIs dispersibility in chitin sponge matrix controlled by its hydrophilicity and adsorption effects on MPs. With the increase of PANIs' hydrophilicity (WCA from 153.9° to 32.8°), the removal efficiency of sponges to MPs increased from 84.0 % to 91.7 %. More hydrophilic PANIs can provide more contact surfaces and adsorption sites, which enhanced the electrostatic interactions to MPs and obtained excellent adsorption properties. The adsorption of MPs on ChPANIs accorded with the pseudo-first-order adsorption, suggesting that physical adsorption plays a dominant role. The adsorption process also conformed to Freundlich model, which displayed the MPs adsorption on ChPANI-PA could be multi-layer. The adsorption strength of ChPANIs was 0.7552, suggesting that it was a strong adsorbent. The ChPANIs also exhibited good mechanical properties and reusability, which its MPs removal efficiency just decreased from 91.7 % to 86.9 % during the five cycles. These findings expand the understanding of the adsorption mechanism analysis of MPs on sponge materials, and exist guiding significance for the design of adsorbed materials.

Variation of PM2.5 and PM10 in emissions and chemical compositions in different seasons from a manure-belt laying hen house.

Particulate matter (PM) emissions from animal houses and the corresponding hazard have raised increasing attention during recent years. In this study, a large-scale manure-belt laying hen house located in Beijing, China was selected as the experimental site for the study of the emission rates (ER) and chemical compositions of PM2.5 and PM10 in 3 seasons, namely, summer, autumn, and winter, to investigate their possible influences on ambient air quality and human health. The results showed that the mean ER from the hen house in summer, autumn, and winter were 9.0 ± 1.7, 2.4 ± 0.7, and 1.9 ± 0.7 mg hen-1 d-1 for PM2.5 (P < 0.05), and 30.7 ± 1.1, 12.8 ± 1.5, and 10.9 ± 0.9 mg hen-1 d-1 for PM10 (P < 0.05), respectively. Moreover, large amounts of secondary inorganic aerosols (SIA) were observed inside the house in summer, accounting for 11.4 and 9.6% of indoor PM2.5 and PM10 mass, respectively, compared with the value of <1.4% in autumn and winter. Among the 31 detected elements in indoor PM, arsenic concentration exceeded the threshold set in legislation. Zn had a notably high concentration of 3,403 to 4,432 ng m-3 in indoor PM10, which was 28 to 71 times higher than that in ambient PM10. The findings suggest that the poultry-raising house emit PM2.5 and PM10 containing SIA and toxic heavy-metal elements such as As and Zn to the ambient with much more emissions in summer than in autumn and winter. Considering the increasing development of poultry-raising farming in China, the potential hazard derived from the exhaust of PM2.5 and PM10 should be focused on, especially during summer.

Quality of life for patients with in-stent restenosis after interventional therapy of peripheral artery disease.

OBJECTIVE: The aim of this study was to investigate the quality of life for patients with in-stent restenosis after interventional therapy of peripheral artery disease and the influencing factors. METHODS: A total of 72 in-stent restenosis patients after interventional therapy of peripheral artery disease were enrolled, whose general data were obtained. SF-12 scale was used to evaluate the quality of life. Tilburg Frailty Scale was used to assess senile debilitation. Pittsburgh Quality Index Scale was used to evaluate sleep quality. Activity of Daily Living Scale was used to evaluate the self-care ability. The general data and in-stent restenosis-related indicators were compared between patients with low and high quality of life, respectively. Multivariate regression analysis was made on the factors affecting quality of life. RESULTS: The average total quality of life score of 72 patients was 74.06±19.26 points. The gender, Fontaine stage and smoking, Activity of Daily Living Scale score, painless walking distance, senile debilitation score, sleep quality score, white blood cells, and C-reactive protein had significant differences between the two groups, respectively (p<0.05). Multivariate regression analysis showed that the female gender, low Fontaine stage (OR=0.186), low senile debilitation score (OR=0.492), and high sleep quality score (OR=0.633) were the protective factors for high quality of life (all p<0.05), and the low Activity of Daily Living score (OR=1.282) was the risk factor for high quality of life (p<0.05). CONCLUSION: Quality of life of in-stent restenosis patients after interventional therapy of peripheral artery disease is low. Gender, Fontaine stage, senile debilitation, sleep quality, and Activity of Daily Living score are the influencing factors of quality of life for in-stent restenosis patients.

Multivariate and multi-interface insights into carbon and energy recovery and conversion characteristics of hydrothermal carbonization of biomass waste from duck farm.

High lipid, high nitrogen duck manure (DM) with high lipid, high lignocellulosic litter materials (LM) are the main wet biomass wastes from duck farms and both are naturally abundant carbon resources. The synthesis of duck farming biomass waste into carbon-rich materials for high value utilization by hydrothermal carbonization (HTC), which can directly treat wet biomass, has not been investigated. In this study, the physicochemical properties of hydrochar derived from co-HTC of DM and LM and its carbon and energy recovery patterns were systematically investigated under multivariate conditions of raw materials ratios, solids contents, temperatures and residence times. The application of synchrotron-based near-edge X-ray adsorption fine structure technique (C K-edge NEXAFS) combined with gas chromatography-mass spectrometry (GC-MS) to the hydrochar and hydrothermal liquid, respectively. At multiple interfaces provided an in-depth analysis of the important material transformations of the co-HTC process and the structure of the hydrochar. Extending residence time (180 min) and increasing LM ratio (M@4%) in co-HTC reaction of DM and LM is beneficial to achieve hydrochar containing higher carbon content (44.84%) at lower reaction temperatures (180 °C). The heating value (HHV) of the hydrochar ranges between 17.12 and 25.05 MJ/kg. The carbon recovery rate of the co-HTC of DM and LM all exceeded 55% and was more closely related to the carbon content of the hydrochar than to its yield. Additionally, the model ERR=0.97±0.01CRR+2.40±0.71 (R2 = 0.99, P < 0.01) was developed to predict energy recovery rate (ERR) based on carbon recovery rate (CRR). Esters were an important intermediate during co-HTC of DM and LM, and the derived hydrochar consisted of a wide range of polycyclic aromatic hydrocarbons, alkanes and N-aromatic heterocycles as well as polyfuran, pyrrole and pyridine structures.

Status and influencing factors of frailty in patients with restenosis after percutaneous transluminal angioplasty for peripheral arterial disease: A cross-sectional study.

This study aimed to investigate the frailty of patients with restenosis after percutaneous transluminal angioplasty (PTA) for peripheral arterial disease, explore the influencing factors, and determine its key factors to take targeted care measures and provide a basis for further interventional care. We recruited as many eligible subjects as possible and a total of 106 patients with restenosis after PTA for peripheral arterial disease in our hospital finished this study from January 2016 to August 2021. The Shorter 12-item version of health-related quality of life scale, Chinese Tilburg debility scale, Pittsburgh sleep quality index scale and activities of daily living score scale were used for investigation, and the independent influencing factors of patients' frailty were evaluated by multivariate logistic regression analysis. The incidence of frailty in restenosis after PTA was 72.6%. Logistic regression analysis found that high levels of C-reactive protein (odds ratios [OR] = 1.080, 95% confidence interval [CI] 1.012-1.153), diabetes (OR = 2.531, 95% CI 1.024-6.257) and advanced age (OR = 1.170, 95% CI 1.042-1.314) were risk factors for restenosis patients frailty, and higher scores of shorter 12-item version of health-related quality of life scale (OR = 0.889, 95% CI 0.813-0.973) was a protective factor for frailty in these patients. The incidence of debilitation in patients with restenosis after PTA for peripheral arterial disease is high, and high C-reactive protein levels, diabetes mellitus and advanced age are significantly associated with restenosis patients. Improving the quality of life of restenosis patients can reduce the occurrence of frailty.

Responses of CH4, N2O, and NH3 emissions to different slurry pH values of 5.5-10.0: Characteristics and mechanisms.

Animal slurry storage is a significant source of greenhouse gas (GHG) and ammonia (NH3) emissions. pH is a basic but key factor that could pose great influence on gas emissions, but the simultaneous evaluation of its influence on GHG and NH3 emissions and the understanding of its underlying mechanism are not enough. In this work, pH was adjusted between 5.5 and 10.0 by a step of 0.5 unit by adding lactic acid and sodium hydroxide (NaOH) properly and frequently to the stored slurry during a 43-day storage period. The cumulative NH3 emissions were linearly correlated with the slurry pH, with R2 being 0.982. Maintaining the slurry pH at 5.5-6.0 could reduce NH3 emissions by 69.4%-85.1% compared with the non-treated group (CK). The pH ranges for maximum methane (CH4) and nitrous oxide (N2O) emissions were 7.5-8.5 and 6.5-8.5, respectively, and the slurry under pH 7.5-8.5 showed the highest GHG emissions. Acidification to pH 5.5 helped reduce the CH4, N2O, and total GHG emissions by 98.0%, 29.3%, and 81.7%, respectively; while alkalinization to pH 10.0 helped achieve the mitigation effects of 74.1%, 24.9%, and 30.6%, respectively. The Pearson's correlation factor between CH4 and the gene copy of mcrA under different pH values was 0.744 (p < 0.05). Meanwhile, the correlation factors between N2O and the gene copies of amoA, narG, and nirS were 0.644 (p < 0.05), 0.719 (p < 0.05), and 0.576 (p = 0.081), respectively. The gene copies of mcrA, amoA, narG, and nirS were maintained at the lowest level under pH 5.5. These results recommended keeping slurry pH lower than 5.5 with lactic acid can help control GHG and NH3 emissions simultaneously and effectively.

Experimental study and theoretical analysis on fluidized activation of coal gasification fly ash from an industrial CFB gasifier.

The gasification fly ash (GFA), a bulk industrial solid waste from coal gasification process, urgently needs to be effectively disposed. In order to use the GFA as porous carbon materials, fluidized activation experiments of the GFA from an industrial circulating fluidized bed (CFB) gasifier were conducted in a bench-scale CFB test rig, as well as steam activation experiments of GFA in a vertical tube furnace and theoretical analysis on the activation process. Due to the ultrafine particle size, the GFA faces a fluidization problem and auxiliary particles are needed to stabilize its fluidization. In the fluidized activation, the pore structure of GFA particles becomes developed in a seconds-level time (about 1.5 s). The specific surface area (SBET) of activated GFA increases with temperature, maximally increasing by 48.9 % and reaching 204 m2/g. Steam activation experiments show that the GFA has an activation potential of 362 m2/g (SBET) and the pore structure evolution of GFA can be quantified by carbon conversion ratio. Based on this, the fluidized activation of GFA is found in the stage of pore development. By appropriately increasing the carbon conversion ratio (below 40 %), the fluidized activation effect of GFA is expected to be improved. Theoretical analysis indicates for the GFA the features of ultra-fine particle size and well-developed pore structure greatly enhance the diffusion rate of active component into the particles. Under the strong diffusion effect, increasing temperature is a critical means to realize the rapid and effective activation of GFA in a finite time.

Microbial composition play the leading role in volatile fatty acid production in the fermentation of different scale of corn stover with rumen fluid.

Rumen fluid is a natural and green biocatalyst that can efficiently degrade biomass into volatile fatty acid (VFA) used to produce value-added materials. But the essence of high degradation efficiency in the rumen has not been fully analyzed. This study investigated the contribution of substrate structure and microbial composition to volatile fatty acid production in the fermentation of corn stover. The ball milled corn stover were innovatively applied to ferment with the rumen fluid collected at different digestion times. Exogeneous cellulase was also added to the ruminal fermentation to further reveal the inner mechanism. With prolonged digestion time, the microbial community relative abundance levels of Bacteroidetes and Firmicutes increased from 29.98% to 72.74% and decreased from 51.76% to 22.11%, respectively. The highest VFA production of the corn stover was achieved via treatment with the rumen fluid collected at 24 h which was up to 9508 mg/L. The ball milled corn stover achieved high VFA production because of the more accessible substrate structure. The application of exogenous cellulase has no significant influence to the ruminal fermentation. The microbial community abundance contributed more to the VFA production compared with the substrate structures.

Quality of life for patients with in-stent restenosis after interventional therapy of peripheral artery disease

SUMMARY OBJECTIVE: The aim of this study was to investigate the quality of life for patients with in-stent restenosis after interventional therapy of peripheral artery disease and the influencing factors. METHODS: A total of 72 in-stent restenosis patients after interventional therapy of peripheral artery disease were enrolled, whose general data were obtained. SF-12 scale was used to evaluate the quality of life. Tilburg Frailty Scale was used to assess senile debilitation. Pittsburgh Quality Index Scale was used to evaluate sleep quality. Activity of Daily Living Scale was used to evaluate the self-care ability. The general data and in-stent restenosis-related indicators were compared between patients with low and high quality of life, respectively. Multivariate regression analysis was made on the factors affecting quality of life. RESULTS: The average total quality of life score of 72 patients was 74.06±19.26 points. The gender, Fontaine stage and smoking, Activity of Daily Living Scale score, painless walking distance, senile debilitation score, sleep quality score, white blood cells, and C-reactive protein had significant differences between the two groups, respectively (p<0.05). Multivariate regression analysis showed that the female gender, low Fontaine stage (OR=0.186), low senile debilitation score (OR=0.492), and high sleep quality score (OR=0.633) were the protective factors for high quality of life (all p<0.05), and the low Activity of Daily Living score (OR=1.282) was the risk factor for high quality of life (p<0.05). CONCLUSION: Quality of life of in-stent restenosis patients after interventional therapy of peripheral artery disease is low. Gender, Fontaine stage, senile debilitation, sleep quality, and Activity of Daily Living score are the influencing factors of quality of life for in-stent restenosis patients.

Effective removal of humic acid by mesoporous Zr-MOF adjusted through SDBS.

Humic acid (HA) in makeup water is one of the important safety issues of high-parameter power plants. Herein, the Zr-based metal-organic frameworks (NH2-UiO-66) was applied to remove humic acid in water. The mesoporous of NH2-UiO-66 was controlled by surfactants sodium dodecyl benzene sulfonate (SDBS) to increase the adsorption of HA. The adsorption of HA at 25°C and pH 7 increased fast at the first 0.5 h and then gradually reached equilibrium after 10 h. The maximum adsorption capacity was 108.93 mg g-1, which removal efficiency was high as 95.0%. The morphology and adsorption properties of NH2-UiO-66 were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), surface charge, Fourier transform infrared (FT-IR), N2 adsorption-desorption, and adsorption test. The adsorption process of HA accorded with the pseudo-second-order kinetics, while the adsorption isotherm conformed to be the Langmuir model and the adsorption was proved to be monolayer adsorption. Adsorption was the spontaneous and endothermic process (ΔG°<0, ΔH°>0). The accessible surface area provided by mesopores on the 5 different Zr-MOFs was the reason for the enhanced HA adsorption capacity. These results provided useful information for effective HA removing and enhanced our understanding of the adsorption mechanism of HA on NH2-UiO-66.

Impact of anaerobic digestion on reactive nitrogen gas emissions from dairy slurry storage.

Biogas digesters are commonly used to treat animal manure/slurry, and abundant digested slurry is generated during the digestion process. Gas emissions from digested and raw slurry may vary with the change in slurry parameters after digestion, but the mechanism is not well understood. Gas emissions from raw dairy slurry (RS) and digested dairy slurry (BS) during 98 days of storage were investigated in this study to evaluate the effects of anaerobic digestion on reactive nitrogen emissions from slurry storage. Results showed that much higher N2O and NO emission and lower NH3 emission was achieved in BS than in RS. The mean gaseous emission of RS and BS accounted for 27.8% ± 6.9% and 17.1% ± 2.3% of the initial TN for NH3, 0.1% ± 0.1% and 3.5% ± 1.6% of the initial TN for N2O, and 0.0% ± 0.0% and 0.2% ± 0.0% of the initial TN for NO, respectively. Among all detected N2O-forming and reducing microbial genes, the abundance of amoA genes was the most closely related to N2O flux (r = 0.54, p < 0.01). More aerobic conditions occurred in BS, and dissolved oxygen (DO) increased to 0.4-1.6 mg L-1 after 35 days because the low organic matter of BS resulted in good infiltration of surface air into the slurry. The increased DO stimulated the growth of Nitrosomonas and the increase in amoA gene copies and contributed to the high N2O and NO emissions in BS through the nitrification process. Vulcanibacillus, Thauera, Castellaniella, and Thermomonas were the major denitrifying bacteria that occurred in BS and caused an incomplete denitrification process, which could be another reason for the increase in N2O and NO emissions from BS. Our study indicated that anaerobic digestion reduced the organic matter content of the slurry and caused an active microbial environment that facilitated the transformation of slurry N to N2O in BS storage, thus lowering the NH3 emission compared with RS storage. Therefore, aside from NH3, N2O should also be preferentially mitigated during BS storage because N2O is a greenhouse gas with high global warming potential.

Medication Adherence and Its Influencing Factors Among Inflammatory Bowel Disease Patients in China.

Purpose: To investigate the current state of medication adherence among patients with inflammatory bowel disease (IBD) in China and analyze the influencing factors. Patients and Methods: We recruited as many eligible subjects as possible and a total of 105 patients with IBD finished this cross-sectional survey. The General Information Questionnaire and Morisky Medication Adherence Scale were used as measurement instruments. The factors influencing the Morisky score were studied by multiple linear regression analysis. Results: The average Morisky score was 6.11 ± 1.93. Univariate analysis showed that there were statistically significant differences in Morisky scores among patients with different ages, education levels, disease types, medication administration methods, medication frequencies, disease understanding and knowledge learning frequencies (P < 0.05). Multiple stepwise linear regression analyses showed that medication frequency, medication administration method and disease understanding were important factors influencing the Morisky score (P < 0.001). Conclusion: Our data confirmed that the medication adherence of IBD patients was poor, especially among patients taking oral medication, those taking medications with a high frequency and those with a low understanding of the disease. To reduce symptom recurrence and control the disease, medical staff should pay attention to the individual patient factors, simplify the medication regimens, formulate effective coping strategies for drug management support.

Integrated livestock sector nitrogen pollution abatement measures could generate net benefits for human and ecosystem health in China.

Nearly one quarter of global meat production occurs in China, but a lack of detailed spatial livestock production data hinders ongoing pollution mitigation strategies. Here we generate high-resolution maps of livestock systems in China using over 480,000 farm surveys from 2007 to 2017, finding that China produced more livestock protein with fewer animals and less total pollution impact through better breeding, feeding and manure management in large-scale livestock farms. Hotspots of production can be observed across the North China Plain, Northeastern China and the Sichuan Basin. The Clean Water Act reduced manure nutrient losses to water by one third, but with limited changes to methane and ammonia emissions. Integrated production and consumption abatement measures costing approximately US$6 billion could further reduce livestock pollution by 2050, realizing benefits of up to US$30 billion due to avoided human health and ecosystem costs.

The Pilot Study of the Influence of Free Ammonia on Membrane Fouling during the Partial Nitrosation of Pig Farm Anaerobic Digestion Liquid.

The problem of membrane fouling is a key factor restricting the application of the membrane bioreactor (MBR) in the partial nitrosation (PN) and anaerobic ammonia oxidation (anammox) processes. In this study, the pilot-scale continuous flow MBR was used to start up the partial nitrosation process in order to investigate the change trend of mid-transmembrane pressure (TMP) in the process of start-up, which was further explored to clarify the membrane fouling mechanism in the pilot-scale reactor. The results showed that the MBR system was in a stable operating condition during the partial nitrosation operation and that the online automatic backwash operation mode is beneficial in alleviating membrane fouling and reducing the cost of membrane washing. Particular attention was paid to the influence trend of free ammonia (FA)on membrane fouling, and it was found that the increase in FA concentration plays the most critical role in membrane fouling. The increase in FA concentration led to an increase in the extracellular polymer (EPS), dissolved microorganism product (SMP) and soluble chemical oxygen demand (SCOD) concentration. FA was extremely significantly correlated with EPS and SCOD, and the FA concentration was approximately 20.7 mg/L. The SCODeff (effluent SCOD concentration) concentration was approximately 147 mg/L higher than the SCODinf (influent SCOD concentration) concentration. FA mainly affects membrane fouling by affecting the concentration of EPS and SCOD.

Strategies to reduce ammonia emissions from livestock and their cost-benefit analysis: A case study of Sheyang county.

Ammonia (NH3) emissions, the majority of which arise from livestock production, are linked to high concentration of PM2.5 and lower air quality in China. NH3 mitigation options were well studied at the small-scale (laboratory or pilot), however, they lack of a large-scale test in China. This study fills this crucial gap by evaluating the cost-benefit of pioneering NH3 mitigation projects carried out for a whole county - Sheyang, Jiangsu province, China. Measures were implemented in 2019 following two distinct strategies, improved manure treatment for industrial livestock farms, and collection and central treatment for traditional livestock farms. Emission reductions of 16% were achieved in a short time. While this is remarkable, it falls short of expectations from small-scale studies. If measures were fully implemented according to purpose and meet expectations from the small scale, higher emission reductions of 42% would be possible. The cost benefit analysis presented in this study demonstrated advantages of central manure treatment over in-farm facilities. With improved implementation of mitigation strategies in industrial livestock farms, traditional livestock farms may play an increasing role in total NH3 emissions, which means such farms either need to be included in future NH3 mitigation policies or gradually replaced by industrial livestock farms. The study found an agricultural NH3 reduction technology route suitable for China's national conditions (such as the "Sheyang Model").