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ACS Omega Jun 2024At present, the identification of the main factors controlling low-production coalbed methane (CBM) wells and production enhancement measures does not consider...
At present, the identification of the main factors controlling low-production coalbed methane (CBM) wells and production enhancement measures does not consider geological and reservoir differences between individual wells and the CBM production effect of well groups simultaneously. In view of this, an evaluation index system suitable for use on inefficient well-blocks was established, which involves their geological resource potential, ground stress, coal structure, and comprehensive permeability under engineering influences from a systemic perspective. The main geological engineering types were determined by zoning superposition, and the corresponding stimulation measures were proposed. The evaluation results of the Shizhuang South Block in the Qinshui Basin show that the area of interest can be divided into Class I, II, and III potential areas, of which the Class II potential areas are subdivided into six blocks. In Zone I, the horizontal well infill method is preferred to increase the CBM production from well groups. At the current level of technology, it is difficult to gain economic benefits from Zone III. In Zone II, these stimulation measures such as the infilling method of staged fracturing horizontal wells, refracturing under supplementary injection holes, roof fracturing, the combined method of acidification and secondary fracturing or nitrogen injection and secondary fracturing, the combined method of acidification and controlled displacement secondary fracturing, and controlled displacement repetitive roof fracturing, among others, can be adopted.
PubMed: 38882112
DOI: 10.1021/acsomega.3c10096 -
ACS Omega Jun 2024The adsorption of CO by coal leads to changes in its mechanical properties, particularly when considering supercritical CO and water with supercritical CO adsorption....
The adsorption of CO by coal leads to changes in its mechanical properties, particularly when considering supercritical CO and water with supercritical CO adsorption. This is strongly linked to the efficiency of CO-enhanced coalbed methane (CO-ECBM) extraction and the safety of CO geological storage. This study focuses on 3 coal from the Datong Mine in Gaoping City, Shanxi Province. The high-rank coal's mechanical properties, including the triaxial compressive strength and elastic modulus, were examined under the combined effects of CO injection pressure, CO injection time, and moisture content. The triaxial compressive strength and elastic modulus of the coal showed a decrease following CO injection. Increasing the CO injection pressure, prolonging the CO injection time, and increasing the moisture content were favorable for coal softening. In particular, the triaxial compressive strength and elastic modulus of the coal sample after 144 h of water and supercritical CO softening decreased by 67.67 and 64.15%, respectively. Injecting CO into coal changed its failure mode. The dry raw coal sample exhibited a brittle shear failure mode, while the coal samples showed transitional shear failure after injecting 6 MPa CO and 8 MPa CO and ductile nondilatant barreling failure after injecting water and 8 MPa CO (with a moisture content of 3.02%). Moreover, the cumulative acoustic emission energy of the coal samples followed a similar trend to the decrease in mechanical properties under different conditions. The physical and chemical interactions among coal, CO, and water caused the softening of coal; these included the generation of the swelling stress, the dissolution of minerals by carbonate solutions, the reduction in surface energy of coal owing to CO adsorption, and the extraction and plasticization reactions of organic matter in coal. The research results are of great significance for further understanding CO-ECBM and CO geological sequestration.
PubMed: 38882111
DOI: 10.1021/acsomega.4c02599 -
ACS Omega Jun 2024The direct conversion of methane (CH), a main greenhouse gas, to value-added chemicals has attracted increasing attention in order to alleviate the current energy crisis...
The direct conversion of methane (CH), a main greenhouse gas, to value-added chemicals has attracted increasing attention in order to alleviate the current energy crisis and environmental concern. Nevertheless, the oriented conversion of CH to target product is formidably challenging due to the inertness of CH. In this work, we demonstrate that zeolite modified by a low amount of GaO (GS-1) can serve as a highly active and stable catalyst for direct conversion to hydrogen (H) and solid carbon. The optimal GS-1 with 0.62 wt % of Ga displays a CH conversion rate of 70.6 mol/g/h with a H productivity of 134 mol/g/h at 800 °C. Analysis on NH temperature-programmed desorption (TPD) and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) suggests that the introduction of GaO can poison the acidic site of zeolite and promote the dehydrogenation of CH. This work reports a highly active and stable catalyst for direct methane conversion, which may provide a feasible strategy for the sustainable utilization of CH.
PubMed: 38882109
DOI: 10.1021/acsomega.4c02136 -
Scientific Reports Jun 2024According to the Intergovernmental Panel on Climate Change (IPCC) of the United Nations (UN), rise in atmospheric concentration of carbon dioxide (CO ) due to...
According to the Intergovernmental Panel on Climate Change (IPCC) of the United Nations (UN), rise in atmospheric concentration of carbon dioxide (CO ) due to anthropogenic factors is considered as the primary driver for global climate change. With almost every major corporation around the world working towards their "net-zero goals", it is becoming increasingly important to have more technologies that can help reduce carbon footprint. Achieving sequestration of CO in the subsurface through Carbon Capture Utilization and Storage (CCUS) technologies like CO -Enhanced Oil Recovery, CO -Enhanced Geothermal Systems, CO -Enhanced Coal Bed Methane, etc. is well accepted. We introduce yet another attractive CCUS opportunity through well rehabilitation. Aqua Freed and Aqua Gard are well-known well rehabilitation and preventive well maintenance technologies that utilize (inject underground) liquid CO for the purpose. The goal of this study was to quantify the storage capacity of Aqua Freed and Aqua Gard, and establish their CCUS credentials. Depending on the well being serviced, these technologies can inject up to 40 US tons of CO per well. Based on field data collection and statistical modeling, we estimated that 82-96% (median 90%) of the injected CO remains in the subsurface post injection. Overall, our results and analysis of the US market suggest that using CO for well rehabilitation and maintenance has a storage potential of several megatonnes of CO annually in the US alone.
PubMed: 38879582
DOI: 10.1038/s41598-024-64135-z -
Bioresource Technology Jun 2024Particulate matter hydrolysis is the bottleneck in anaerobic treatment of municipal wastewater in temperate climates. Low temperatures theoretically slow...
Particulate matter hydrolysis is the bottleneck in anaerobic treatment of municipal wastewater in temperate climates. Low temperatures theoretically slow enzyme-substrate interactions, hindering utilization kinetics, but this remains poorly understood. β-glucosidase, protease, and lipase activities were evaluated in two pilot-scale upflow anaerobic sludge blanket (UASB) reactors, inoculated with different sludges and later converted to anaerobic membrane bioreactors (AnMBRs). Despite similar methane production and solids hydrolysis rates, significant differences emerged. Specific activity peaked at 37 °C, excluding the predominance of psychrophilic enzymes. Nevertheless, the Michaelis-Menten constant (Km) indicated high enzyme-substrate affinity at the operational temperature of 15-20 °C, notably greater in AnMBRs. It is shown, for the first time, that different seed sludges can equally adapt, as hydrolytic enzymatic affinity to the substrate reached similar values in the two reactors at the operational temperature and identified that membrane ultrafiltration impacted hydrolysis by a favourable enzyme Michaelis-Menten constant.
PubMed: 38879058
DOI: 10.1016/j.biortech.2024.130975 -
FEBS Open Bio Jun 2024Methyl-coenzyme M reductase (MCR) is a multi-subunit (αβγ) enzyme responsible for methane formation via its unique F cofactor. The genes responsible for producing MCR...
Methyl-coenzyme M reductase (MCR) is a multi-subunit (αβγ) enzyme responsible for methane formation via its unique F cofactor. The genes responsible for producing MCR (mcrA, mcrB and mcrG) are typically colocated with two other highly conserved genes mcrC and mcrD. We present here the high-resolution crystal structure for McrD from a human gut methanogen Methanomassiliicoccus luminyensis strain B10. The structure reveals that McrD comprises a ferredoxin-like domain assembled into an α + β barrel-like dimer with conformational flexibility exhibited by a functional loop. The description of the M. luminyensis McrD crystal structure contributes to our understanding of this key conserved methanogen protein typically responsible for promoting MCR activity and the production of methane, a greenhouse gas.
PubMed: 38877345
DOI: 10.1002/2211-5463.13848 -
Journal of Dairy Science Jun 2024This research introduces a systematic framework for calculating sample size in studies focusing on enteric methane (CH, g/kg of DMI) yield reduction in dairy cows....
This research introduces a systematic framework for calculating sample size in studies focusing on enteric methane (CH, g/kg of DMI) yield reduction in dairy cows. Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a comprehensive search across the Web of Science, Scopus, and PubMed Central databases for studies published from 2012 to 2023. The inclusion criteria were: studies reporting CH yield and its variability in dairy cows, employing specific experimental designs (Latin Square Design (LSD), Crossover Design, Randomized Complete Block Design (RCBD), and Repeated Measures Design) and measurement methods (Open-circuit respirometry chambers (RC), the GreenFeed system, and the sulfur hexafluoride tracer technique), conducted in Canada, the United States and Europe. A total of 150 studies, which included 177 reports, met our criteria and were included in the database. Our methodology for using the database for sample size calculations began by defining 6 CH yield reduction levels (5, 10, 15, 20, 30, and 50%). Utilizing an adjusted Cohen's f formula and a power analysis we calculated the sample sizes required for these reductions in balanced LSD and RCBD reports from studies involving 3 or 4 treatments. The results indicate that within-subject studies (i.e., LSD) require smaller sample sizes to detect CH yield reductions compared with between-subject studies (i.e., RCBD). Although experiments using RC typically require fewer individuals due to their higher accuracy, our results demonstrate that this expected advantage is not evident in reports from RCBD studies with 4 treatments. A key innovation of this research is the development of a web-based tool that simplifies the process of sample size calculation (samplesizecalculator.ucdavis.edu). Developed using Python, this tool leverages the extensive database to provide tailored sample size recommendations for specific experimental scenarios. It ensures that experiments are adequately powered to detect meaningful differences in CH emissions, thereby contributing to the scientific rigor of studies in this critical area of environmental and agricultural research. With its user-friendly interface and robust backend calculations, this tool represents a significant advancement in the methodology for planning and executing CH emission studies in dairy cows, aligning with global efforts toward sustainable agricultural practices and environmental conservation.
PubMed: 38876218
DOI: 10.3168/jds.2023-24529 -
Journal of Colloid and Interface Science May 2024Developing an efficient electrocatalyst that enables the efficient electrochemical conversion from CO to CH across a wide potential range remains a formidable challenge....
Developing an efficient electrocatalyst that enables the efficient electrochemical conversion from CO to CH across a wide potential range remains a formidable challenge. Herein, we introduce a precatalyst strategy that realizes the in situ electrochemical reconstruction of ultrafine CuO nanodomains, intricately coupled on the CeO surface (CuO/CeO), originating from the heterointerface comprised of ultrafine CuO nanodomains on the CeO surface (CuO/CeO). When served as the electrocatalyst for the electrochemical CO reduction reaction, CuO/CeO delivers a selectivity higher than 49 % towards CH over a broad potential range from -1.2 V to -1.7 V vs. RHE, maintaining negligible activity decay for 20 h. Notably, the highest selectivity for CH reaches an impressive 70 % at -1.5 V vs. RHE. Through the combination of comprehensive analysis including synchrotron X-ray absorption spectroscopy, spherical aberration-corrected high-angle annular dark field scanning transmission electron microscope as well as the density functional theoretical calculation, the efficient production of CH is attributed to the coherent interface between CuO and CeO, which could converted from the original CuO and CeO interface, ensuring abundant active sites and enhanced intrinsic activity and selectivity towards CH.
PubMed: 38875798
DOI: 10.1016/j.jcis.2024.05.212 -
Frontiers in Veterinary Science 2024Garlic skin (GAS) has been proven to improve the growth performance of fattening sheep. However, the mechanism by which GAS affects fattening sheep is not yet clear. The...
OBJECTIVE
Garlic skin (GAS) has been proven to improve the growth performance of fattening sheep. However, the mechanism by which GAS affects fattening sheep is not yet clear. The aim of this study is to investigate the effects of adding GAS to feed on the growth performance, rumen and fecal microbiota, serum and urine metabolism, and transcriptomics of rumen epithelial cells in fattening sheep.
METHODS
GAS with 80 g/kg dry matter (DM) was added to the diet of fattening sheep to study the effects of GAS on gut microbiota, serum and urine metabolism, and transcriptome of rumen epithelial tissue in fattening sheep. Twelve Hu sheep (body weights; BW, 23.0 ± 2.3 kg and ages 120 ± 3.5 d) were randomly divided into two groups. The CON group was the basal diet, while the GAS group was supplemented with GAS in the basal diet. The trial period was 10 weeks, with the first 2 weeks being the pre-trial period.
RESULTS
The daily average weight gain of fattening sheep in the GAS group was significantly higher than that in the CON group ( < 0.05), and the serum GSH-Px of the GAS group fattening sheep was significantly increased, while MDA was significantly reduced ( < 0.05). Based on the genus classification level, the addition of garlic peel in the diet changed the intestinal microbial composition, and the relative abundance was significantly upregulated by ( < 0.05), while significantly downregulated by , , and ( < 0.05). Metabolomics analysis found that there were 166 significantly different metabolites in serum and 68 significantly different metabolites in urine between the GAS and CON groups ( < 0.05). GAS had an impact on amino acid metabolism, pyrimidine metabolism, methane metabolism, riboflavin metabolism, and unsaturated fatty acid synthesis pathways ( < 0.05). Transcriptome sequencing showed that differentially expressed genes were mainly enriched in immune regulatory function, improving the health of fattening sheep.
CONCLUSION
Adding GAS can improve the energy metabolism and immune function of fattening sheep by altering gut microbiota, metabolome, and transcriptome, thereby improving the growth performance of fattening sheep.
PubMed: 38872796
DOI: 10.3389/fvets.2024.1409518 -
Scientific Reports Jun 2024Feed cost represents a major economic determinant within cattle production, amounting to an estimated 75% of the total variable costs. Consequently, comprehensive...
Feed cost represents a major economic determinant within cattle production, amounting to an estimated 75% of the total variable costs. Consequently, comprehensive approaches such as optimizing feed utilization through alternative feed sources, alongside the selection of feed-efficient animals, are of great significance. Here, we investigate the effect of two diets, traditional corn-grain fed and alternative by-product based, on 14 phenotypes related to feed, methane emission and production efficiency and on multi-tissue transcriptomics data from liver, muscle, and rumen wall, derived from 52 Nellore bulls, 26 on each diet. To this end, diets were contrasted at the level of phenotype, gene expression, and gene-phenotype network connectivity. As regards the phenotypic level, at a P value < 0.05, significant differences were found in favour of the alternative diet for average daily weight gain at finishing, dry matter intake at finishing, methane emission, carcass yield and subcutaneous fat thickness at the rib-eye muscle area. In terms of the transcriptional level of the 14,776 genes expressed across the examined tissues, we found 487, 484, and 499 genes differentially expressed due to diet in liver, muscle, and rumen, respectively (P value < 0.01). To explore differentially connected phenotypes across both diet-based networks, we focused on the phenotypes with the largest change in average number of connections within diets and tissues, namely methane emission and carcass yield, highlighting, in particular, gene expression changes involving SREBF2, and revealing the largest differential connectivity in rumen and muscle, respectively. Similarly, from examination of differentially connected genes across diets, the top-ranked most differentially connected regulators within each tissue were MEOX1, PTTG1, and BASP1 in liver, muscle, and rumen, respectively. Changes in gene co-expression patterns suggest activation or suppression of specific biological processes and pathways in response to dietary interventions, consequently impacting the phenotype. The identification of genes that respond differently to diets and their associated phenotypic effects serves as a crucial stepping stone for further investigations, aiming to build upon our discoveries. Ultimately, such advancements hold the promise of improving animal welfare, productivity, and sustainability in livestock farming.
Topics: Animals; Cattle; Liver; Rumen; Animal Feed; Diet; Transcriptome; Male; Muscle, Skeletal; Phenotype; Gene Regulatory Networks; Gene Expression Profiling
PubMed: 38871745
DOI: 10.1038/s41598-024-63619-2