Search Results (276)

While the Ankom RF system facilitates efficient high-throughput in vitro fermentation studies, its high cost and limited flexibility constrain its broader applicability. To address these limitations, we developed and validated a low-cost, modular gas monitoring system (FerME), assembled from commercially available components. To evaluate its performance and reproducibility relative to the Ankom RF system (Ankom Technology, Macedon, NY, USA), in vitro rumen fermentation experiments were conducted under strictly controlled and identical conditions. Whole rumen contents were collected approximately 2 h post-feeding from individual mid- or late-lactation dairy cows and immediately transported to the laboratory. Each fermenter received 50 mL of processed rumen fluid, 100 mL of anaerobically prepared artificial saliva buffer, and 1.2 g of the donor cow’s diet. Bottles were sealed with the respective system’s pressure sensors, flushed with CO₂, and incubated in a 50 L water bath maintained at 39 °C. FerME (New Taipei City, Taiwan) and Ankom RF fermenters were placed side-by-side to ensure uniform thermal conditions. To assess the effect of filter bag use, an additional trial employed Ankom F57 filter bags (Ankom Technology, Macedon, NY, USA; 25 μm pore size). Trial 1 revealed no significant differences in cumulative gas production, volatile fatty acids (VFAs), NH₃-N, or pH between systems (p > 0.05). However, the use of filter bags reduced gas output and increased propionate concentrations (p < 0.05). Trial 2, which employed filter bags in both systems, confirmed comparable results, with the FerME system demonstrating improved precision (CV: 4.8% vs. 13.2%). Gas composition (CH₄ + CO₂: 76–82%) and fermentation parameters remained consistent across systems (p > 0.05). Importantly, with 12 pressure sensors, the total cost of FerME was about half that of the Ankom RF system. Collectively, these findings demonstrate that FerME is a reliable, low-cost alternative for real-time rumen fermentation monitoring and could be suitable for studies in animal nutrition, methane mitigation, and related applications. Full article

High nighttime temperature (HNT) due to asymmetric diurnal warming threatens wheat productivity. This study evaluated the effect of HNT on wheat phenology, physiology, and yield through field and controlled environment experiments in Central Queensland, Australia. Two wheat genotypes, Faraday and AVT#6, were assessed under three sowing dates—1 May (Early), 15 June (Mid), and 1 August (Late)—within the recommended sowing window for the region. In a parallel growth chamber study, the plants were exposed to two nighttime temperature regimes, of 15 °C (normal) and 20 °C (high), with consistent daytime conditions from booting to maturity. Late sowing resulted in shortened vegetative growth and grain filling periods and increased exposure to HNT during the reproductive phase. This resulted in elevated floret sterility, lower grain weight, and up to 40% yield loss. AVT#6 exhibited greater sensitivity to HNT despite maturing earlier. Leaf gas exchange analysis revealed increased nighttime respiration (Rn) and reduced assimilation (A), resulting in higher Rn/A ratio for late-sown crops. The results from controlled environment chambers resembled trends of the field experiment, producing lower grain yield and biomass under HNT. Cumulative nighttime hours above 20 °C correlated more strongly with yield losses than daytime heat. These findings highlight the need for HNT-tolerant genotypes and optimized sowing schedules under future climate scenarios. Full article

In the final phases of casing production, shale gas horizontal wells with a downward slope frequently find it difficult to sustain self-flow production. The ideal tubing insertion depth for self-flow production in gas wells has not been thoroughly studied, even though the timely adoption of tubing production can successfully prolong the self-flow production period. Using a fully dynamic multiphase flow simulation program, the ideal tubing depth for gas well self-flow production was ascertained. A wellbore structural model was built using a particular well as an example. By altering the tubing depth, the formation pressure limit values necessary to sustain gas well self-flow production at various tubing depths were simulated. The appropriate tubing depth for gas well self-flow production was examined, along with the well’s cumulative gas output at various tubing depths. Using the example as a case study, it was discovered that the critical formation pressure for gas well self-flowing production dropped to 7.8 MPa when the tubing was lowered to 2600 m. This effectively increased cumulative production by 56.19 × 10⁶ m³ and extended the self-flow production time by roughly 135 days. The study’s findings offer strong evidence in favor of maximizing shale gas wells’ self-flow production performance in later phases of production. Full article

The Shenhu sea area is rich in unconsolidated hydrate reserves, but the formation mineral particles are small, the rock cementation is weak, and the coupling mechanism of hydrate phase change, fluid seepage, and formation deformation is complex, resulting in unclear productivity change law under depressurization exploitation. Therefore, a thermal–fluid–solid–chemical coupling model for natural gas hydrate depressurization exploitation in the Shenhu sea area was constructed to analyze the variation law of reservoir parameters and productivity. The results show that within 0–30 days, rapid near-well pressure drop (13.83→9.8 MPa, 36.37%) drives peak gas production (25,000 m³/d) via hydrate dissociation, with porosity (0.41→0.52) and permeability (75→100 mD) increasing. Within 30–60 days, slower pressure decline (9.8→8.6 MPa, 12.24%) and fines migration cause permeability fluctuations (120→90 mD), reducing gas production to 20,000 m³/d. Within 60–120 days, pressure stabilizes (~7.6 MPa) with residual hydrate saturation < 0.1, leading to stable low permeability (60 mD) and gas production (15,000 m³/d), with cumulative production reaching 2.2 × 10⁶ m³. This study clarifies that productivity is governed by coupled “pressure-driven dissociation–heat limitation–fines migration” mechanisms, providing key insights for optimizing depressurization strategies (e.g., timed heat supplementation, anti-clogging measures) to enhance commercial viability of unconsolidated hydrate reservoirs. Full article

Food safety concerns related to pesticide residues in fruits and vegetables have increased globally, particularly in regions where monitoring programs are scarce or inconsistent. This study provides the first multi-year evaluation of pesticide contamination and associated dietary risks in Cape Verde, an African island nation increasingly reliant on imported produce. A total of 570 samples of fruits and vegetables—both locally produced and imported—were collected from major markets across the country between 2017 and 2020 and analyzed using validated multiresidue methods based on gas chromatography coupled to Ion Trap mass spectrometry (GC-IT-MS/MS), and both gas and liquid chromatography coupled to triple quadrupole tandem mass spectrometry (GC-QqQ-MS/MS and LC-QqQ-MS/MS). Residues were detected in 63.9% of fruits and 13.2% of vegetables, with imported fruits showing the highest contamination levels and diversity of compounds. Although only one sample exceeded the maximum residue limits (MRLs) set by the European Union, 80 different active substances were quantified—many of them not authorized under the current EU pesticide residue legislation. Dietary exposure was estimated using median residue levels and real consumption data from the national nutrition survey (ENCAVE 2019), enabling a refined risk assessment based on actual consumption patterns. The cumulative hazard index for the adult population was 0.416, below the toxicological threshold of concern. However, when adjusted for children aged 6–11 years—taking into account body weight and relative consumption—the cumulative index approached 1.0, suggesting a potential health risk for this vulnerable group. A limited number of compounds, including omethoate, oxamyl, imazalil, and dithiocarbamates, accounted for most of the risk. Many are banned or heavily restricted in the EU, highlighting regulatory asymmetries in global food trade. These findings underscore the urgent need for strengthened residue monitoring in Cape Verde, particularly for imported products, and support the adoption of risk-based food safety policies that consider population-specific vulnerabilities and mixture effects. The methodological framework used here can serve as a model for other low-resource countries seeking to integrate analytical data with dietary exposure in a One Health context. Full article

Based on a detailed investigation of the geological setting of coalbed methane by previous work in the Xiangzhong Depression, Hunan Province, numerical simulation methods were used to simulate the geological storage of carbon dioxide and displacement gas production in this area. In this simulation, a 400 m × 400 m square well group was constructed for coalbed methane production, and a carbon dioxide injection well was arranged in the center of the well group. Injection storage and displacement gas production simulations were carried out under the conditions of original permeability and 1 mD permeability. At the initial permeability (0.01 mD), carbon dioxide is difficult to inject, and the production of displaced and non-displaced coalbed methane is low. During the 25-year injection process, the reservoir pressure only increased by 7 MPa, and it is difficult to reach the formation fracture pressure. When the permeability reaches 1 mD, the carbon dioxide injection displacement rate can reach 4000 m³/d; the cumulative production of displaced and non-displaced coalbed methane is 7.83 × 10⁶ m³ and 9.56 × 10⁵ m³, respectively, and the average daily production is 1430 m³/d and 175 m³/d. The displacement effect is significantly improved compared to the original permeability. In the later storage stage, the carbon dioxide injection rate can reach 8000 m³/d, reaching the formation rupture pressure after 3 years, and the cumulative carbon dioxide injection volume is 1.17 × 10⁷ m³. This research indicates that permeability has a great impact on carbon dioxide geological storage. During the carbon dioxide injection process, selecting areas with high permeability and choosing appropriate reservoir transformation measures to enhance permeability are key factors in increasing the amount of carbon dioxide injected into the area. Full article

Agricultural greenhouse gas (GHG) emissions contribute significantly to climate change and underline the importance of reliable measurements and mitigation strategies. This life cycle assessment (LCA)-based study evaluates the environmental impacts of four key Mediterranean agricultural products, namely olives, sweet potatoes, corn, and grapes using GHG measurements at four pilot fields located in different regions of Greece. With the use of a cradle-to-gate approach six environmental impact categories, more specifically acidification potential (AP), eutrophication potential (EP), global warming potential (GWP), ozone depletion potential (ODP), photochemical ozone creation potential (POCP), and cumulative energy demand (CED) as energy-based indicator are assessed. The functional unit used is 1 ha of cultivated land. Any potential carbon offsets from mitigation practices are assessed through an integrated low-carbon certification framework and the use of innovative, site-specific technologies. In this context, the present study evaluates three life cycle inventory (LCI)-based scenarios: Baseline (BS), which represents a 3-year crop production period; Field-based (FS), which includes on-site CO₂ and CH₄ measurements to assess the effects of mitigation practices; and Inventoried (IS), which relies on comprehensive datasets. The adoption of carbon mitigation practices under the FS scenario resulted in considerable reductions in environmental impacts for all pilot fields assessed, with average improvements of 8% for olive, 5.7% for sweet potato, 4.5% for corn, and 6.5% for grape production compared to the BS scenario. The uncertainty analysis indicates that among the LCI-based scenarios evaluated, the IS scenario exhibits the lowest variability, with coefficient of variation (CV) values ranging from 0.5% to 7.3%. In contrast, the FS scenario shows slightly higher uncertainty, with CVs reaching up to 15.7% for AP and 14.7% for EP impact categories in corn production. The incorporation of on-site GHG measurements improves the precision of environmental performance and supports the development of site-specific LCI data. This benchmark study has a noticeable transferability potential and contributes to the adoption of sustainable practices in other regions with similar characteristics. Full article

To address the challenges of water coning and early water breakthrough commonly encountered during the development of bottom-water gas reservoirs, this study establishes a fully coupled numerical simulation model integrating a horizontal wellbore, inflow control device (ICD) screens, and a zonal water control system. A novel “dual inflow performance index” method is introduced for the first time, enabling separate calculation of the pressure drops induced by gas and water phases flowing through the ICDs, thereby improving the accuracy of pressure simulations throughout the production lifecycle. The model divides the entire production system into four physically distinct subsystems, the bottom-water gas reservoir, ICD screens, production compartments, and the horizontal wellbore, which are dynamically coupled through transient interflow exchange. Based on geological parameters from the SPE10 dataset, the model simulates realistic production scenarios. The results show that the proposed model accurately captures the time-dependent increase in ICD pressure drop as fluid properties evolve during production. Moreover, the zonal water control method outperforms the single ICD-based control strategy in water control performance, achieving a 23% reduction in cumulative water production. Additionally, the water control intensity of the ICD screens increases nonlinearly with the reduction in the number of openings. In highly heterogeneous reservoirs with significant permeability contrast, effective suppression of water coning can only be achieved by setting a minimal number of openings in the high-permeability compartments, resulting in up to a 15% reduction in cumulative water production. The timing of production compartment shutdown exerts a significant influence on water control performance. The optimal strategy is to first identify the water breakthrough point through unconstrained production simulation as production with all eight ICD screen openings fully open and then shut down the high-permeability production compartment around this critical time. This approach can suppress cumulative water production by up to 27%. Overall, the proposed model offers a practical and robust tool for optimizing completion design and water control strategies in complex bottom-water gas reservoirs. Full article

Agricultural production in Northwest China is widely constrained by residual plastic film pollution, excessive greenhouse gas emissions, and low productivity. Integrating biodegradable film with controlled-release nitrogen fertilizer offers a promising approach to optimize crop management, enhance yield, and improve environmental outcomes. In this study, three planting patterns (conventional flat planting, FP; ridge mulching with biodegradable film, BM; and ridge mulching with conventional plastic film, PM), two nitrogen fertilizer types (urea, U, and controlled-release nitrogen fertilizer, C), and four nitrogen application rates (0, 80, 160, and 240 kg·hm⁻²) were applied to systematically investigate their effects on alfalfa yield and N₂O emissions from grasslands. The results showed that BM and PM increased alfalfa yield by 23.49% and 18.65%, respectively, compared to FP, while C increased yield by 8.46% compared to urea. The highest yield (24.84 t·hm⁻²) was recorded under the BMC2 treatment, which was 97.11% higher than that of FPN0. N₂O emission flux and cumulative emissions increased with nitrogen application rate. Compared with U, C reduced cumulative N₂O emissions and greenhouse gas emission intensity (GHGI) by 23.89% and 25.84%, respectively. Compared to PM, BM reduced cumulative N₂O emissions and GHGI by 11.58% and 20.15%, respectively. Principal component analysis indicated that the combination of ridge mulching with biodegradable film and 160 kg·hm⁻² of C was optimal for simultaneously increasing alfalfa yield and reducing N₂O emissions, making it a suitable planting–fertilization strategy for the Yellow River irrigation district in Gansu and similar ecological regions. Full article

In order to clarify the feasibility of constructing a gas storage reservoir through synergistic injection and production in the target reservoir, micro-displacement experiments and multi-cycle injection–production experiments were conducted. These experiments investigated the displacement characteristics and the factors affecting storage capacity during the multi-cycle injection–production process for converting the target reservoir into a gas storage facility. Microscopic displacement experiments have shown that the remaining oil is primarily distributed in the dead pores and tiny pores of the core in the form of micro-bead chains and films. The oil displacement efficiency of water flooding followed by gas flooding is 18.61% higher than that of gas flooding alone, indicating that the transition from water flooding to gas flooding can further reduce the liquid saturation and increase the storage capacity space by 2.17%. Single-tube long-core displacement experiments indicate that, during the collaborative construction of a gas storage facility, the overall oil displacement efficiency without a depletion process is approximately 24% higher than that with a depletion process. This suggests that depletion production is detrimental to enhancing oil recovery and expanding the capacity of the gas storage facility. During the cyclic injection–production stage, the crude oil recovery rate increases by 1% to 4%. As the number of cycles increases, the incremental oil displacement efficiency in each stage gradually decreases, and so does the increase in cumulative oil displacement efficiency. Better capacity expansion effects are achieved when gas is produced simultaneously from both ends. Parallel double-tube long-core displacement experiments demonstrate that, when the permeability is the same, the oil displacement efficiencies during the gas flooding stage and the cyclic injection–production stage are essentially identical. When there is a permeability contrast, the oil displacement efficiency of the high-permeability core is 9.56% higher than that of the low-permeability core. The ratio of the oil displacement efficiency between the high-permeability end and the low-permeability end is positively correlated with the permeability contrast; the greater the permeability contrast, the larger the ratio. The research findings can provide a reference for enhancing oil recovery and expanding the capacity of the target reservoir when it is converted into a gas storage facility. Full article

The intensive use of nitrogen (N) fertilizers in maize (Zea mays L.) cropping in sub-Saharan Africa (SSA) contributes significantly to nitrous oxide (N₂O) emissions. Due to limited data on emissions and emission factors (EFs) in SSA, this study investigates GHG emissions and proposes EFs under different fertilization regimes in maize cropping in Burkina Faso (West Africa). A randomized complete block design was used with five treatments: (i) control: no fertilizer (CK), (ii) cattle manure (M), (iii) chemical fertilizer (NPK), (iv) a combination of chemical fertilizer and cattle manure (NPKM) at the national recommended rate, and (v) farmers’ practices, which involve chemical fertilizer combined with manure at the farmers’ rate (NPKM+). Cumulative N₂O emissions varied significantly among treatments (p < 0.05), with the highest under NPKM (2.86 kg N₂O-N ha⁻¹) and the lowest under CK (1.93 ± 0.11 kg N₂O-N ha⁻¹). NPKM also showed the highest methane (CH₄) uptake (−0.62 kg CH₄-C ha⁻¹; p < 0.001), while CK exhibited an increasing trend (0.74 kg CH₄-C ha⁻¹). The highest N₂O EF was recorded for NPK (0.37 ± 0.05%), 63% lower than the Intergovernmental Panel on Climate Change default value. Although NPKM treatment resulted in the highest global warming potential and maize yield, it also achieved the lowest greenhouse gas intensity per unit of yield, highlighting a more efficient trade-off between productivity and climate impact with nitrogen fertilizer use. NPKM+ was the most effective in maintaining high maize productivity with lower yield-scaled N₂O emissions and GHG intensity. These findings suggest that an integrated approach combining organic and inorganic fertilizers can mitigate soil GHG emissions. Further research is needed to refine climate-smart fertilizer combinations for sustainable maize production in SSA. Full article

Quantitative greenhouse gas (GHG) budgets for Mediterranean pepper cultivation are still missing, limiting evidence-based nitrogen management. Furthermore, mitigation value of fertigation respect to granular fertilization in vegetable systems remains uncertain. This study therefore compared the GHG footprint and productivity of ‘papaccella’ pepper under two nitrogen fertilization methods: granular fertilization versus low-frequency fertigation with urea, each supplying about 63 kg N ha⁻¹. Eight automated static chambers coupled to a cavity ring-down spectrometer monitored soil CO₂ and N₂O fluxes throughout the season. Cumulative emissions did not differ between treatments (CO₂: 811 ± 6 g m⁻² vs. 881 ± 4 g m⁻²; N₂O: 0.038 ± 0.008 g m⁻² vs. 0.041 ± 0.015 g m⁻², fertigation vs. granular), and marketable yield remained at ~11 t ha⁻¹, leaving product-scaled global warming potential (GWP) unchanged. Although representing less than 2% of measured fluxes, “hot moments,” burst emissions exceeding four standard deviations (SD) from the mean, accounted for up to 4% of seasonal CO₂ and 19% of N₂O. Fertigation doubled the frequency of these events but reduced their peak magnitude, whereas granular application produced fewer but more extreme bursts (>11 SD). Results showed that fertigation did not mitigate GHGs emission nor improve productivity for Mediterranean pepper, mainly due to the low application frequency and the use of a urea fertilizer. Moreover, we can highlight that in horticultural systems, omitting ‘hot moments’ leads to systematic underestimation of emissions. Full article

This study explores how production technology influences spray-applied rigid polyurethane (PUR) foam insulation’s cryogenic performance. In cryogenic applications such as liquid gas storage, insulation must minimise heat transfer and resist moisture ingress under severe thermal gradients. Experimental aluminium vessels were insulated with PUR foam of varying thicknesses and surface conditions—rough, machined smooth, and with a urea-based protective coating—and then tested using dynamic boil-off of liquid nitrogen (LN₂). Foam properties, including adhesion, mechanical strength, thermal expansion, thermal conductivity, and closed-cell content, were evaluated. The results revealed that thicker insulation reduced both effective thermal conductivity and moisture uptake. Although the urea-coated vessel showed minimal water absorption, the coating increased overall thermal conductivity due to its heat conduction and condensation behaviour. Moisture was primarily absorbed near the foam surface, and no cumulative effects were observed during repeated tests. The effective thermal conductivity was determined by interpolating boil-off data, confirming that insulation performance strongly depends on thickness, surface condition, and environmental humidity. These findings provide valuable guidance for the design and application of PUR foam insulation in cryogenic environments. Full article

The production of artificial planted forage is important for the development of animal husbandry in the Qinghai–-Tibet Plateau, and oat forage is one of the main artificial planted forages in the area. However, the suitable oat varieties for harvesting and preparing silage feed in this region are still unclear. To investigate suitable oat forage varieties for silage production and the potential feeding value of different oat forage varieties, 16 oat forage varieties planted in Qinghai Province were selected in this experiment. These oat forages were subjected to two treatments: a group with no inoculants (CK) and a group with self-selected lactic acid bacteria (LAB) inoculants (IN). After 90 days of ensiling, silage quality and in vitro digestibility of the 16 oat forage varieties were determined. The results showed that all oat forage varieties ferment well after ensiling (pH < 4), the CK group had a silage pH range of 3.62–3.95, and the IN group had a silage pH range of 3.68–3.83. Tianyan No.1, Qingtian No.2, and Tianyan No.3 were in the top three in RFV and RFQ rankings in the CK group, while Qinghai 444, Tianyan No.1, and Tianyan No.3 were in the lead in GI rankings. Tianyan No.1, Qingtian No.2, and Everleaf 126 were in the lead in RFV and RFQ rankings in the IN group, while Qinghai 444, Titan, and Tianyan No.1 were in the top three in GI rankings. The dry matter digestibility and 72 h cumulative gas production of the IN group were higher than that of the CK group (p < 0.05). Based on principal component analysis and membership function comprehensive evaluation, Tianyan No.1, Qinghai 444, and Tianyan No.3 ranked the top three, demonstrating that these three oat forage varieties are suitable for silage processing in the Qinghai–Tibet Plateau region. Full article

Malting is one of the most energy-intensive stages in beer brewing, yet its environmental impacts remain under-characterized despite recent efficiency gains. Barley and malt transport drive significant greenhouse gas emissions in import-dependent countries, while local, small-scale production can offset those savings through lower process efficiencies or higher resource use. This study conducted a cradle-to-gate Life Cycle Assessment (LCA) of three Italian malthouses—small, medium, and large—using SimaPro 10.2.0.0 and a functional unit of 1 kg of malted barley delivered by bulk truck to local breweries. Primary data on barley, water, methane, and electricity consumption, as well as waste generation, were collected via questionnaires; secondary data were sourced from Ecoinvent and Agri-Footprint. Impact categories were evaluated using the Cumulative Energy Demand (CED) and Product Environmental Footprint (PEF) methodologies. Barley cultivation dominates the footprint (84–92% of total impacts when using local grain). Drying and transport contribute 3.7–4.4% and 0–8.4% of impacts, respectively, depending on facility scale and import share. Smaller malthouses exhibit higher per-kilogram impacts due to lower energy efficiency and transportation modes. Mitigation strategies —including sustainable agriculture, renewable energy adoption, logistics optimization, and process improvements—can substantially reduce impacts. Notably, sourcing barley from low-impact suppliers alone lowers the carbon footprint from 0.80 to 0.66 kg CO_2e/kg, freshwater eutrophication from 227 to 32 CTU_e/kg, land use from 196 to 136 Pt/kg, and overall PEF from 192 to 81 µPt/kg. These results underscore the critical role of feedstock sourcing and process efficiency in decarbonizing malt production and provide a quantitative baseline for targeted sustainability interventions. Full article