Research on Wellbore Quality Control Technology for Coalbed Methane Deviated Wells

AbstractDeviated well is one of the main well types to develop coalbed methane in China. It's been widely used by various coalbed methane companies in recent years. Compared with traditional oil and gas wells, coalbed methane wells are characterized by shallow depth and strict well spacing, which means higher wellbore quality control technology. Furthermore, coalbed methane wells are apt to produce coal dust during dewatering and coal dust causes serious abrasion of pipe and rod. It's required to improve wellbore quality. This paper analyzes the weakness of current wellbore quality control standard and technology for coalbed methane wells on the basis of the characterization of coaled methane wells and finds out the key factors that control wellbore quality of coalbed methane deviated wells. The technology is developed to improve wellbore quality of coalbed methane wells from trajectory design and real-time control. Through the on-site test in Baode block, Shanxi Province, the technology is further improved and it's confirmed by the test result that this technology can improve the wellbore quality of coalbed methane deviated wells. In addition, this paper also presents some good suggestions for compiling standard about wellbore quality control for coalbed methane deviated wells

Effects of Phosphorus Ensembled Nanomaterials on Nutrient Uptake and Distribution in Glycine max L. under Simulated Precipitation

Nanoscale hydroxyapatite (nHA) was synthesized to investigate its potential as a phosphorus (P) ensembled nanofertilizer, using soybean (Glycine max L.) as a model plant. The conventional analogue phosphate (pi) was used for comparison with the synthesized nHA. Varied precipitation intensities (0%, 30%, 60%, and 100%) were simulated by adding selected volumes of the P fertilizers (nHA or pi) via foliar spray and soil amendment. The total amounts of added P were the same across all the treatments. The importance of a wash-off effect was investigated on foliar-treated seedlings by evaluating different watering heights (20, 120, and 240 cm above the seedlings). Fresh weight, pigment content, macro-, and micronutrient contents were measured in soybean tissues across all the treatments after 4 weeks of greenhouse cultivation. The synthesized nHA showed superior effects on plant nutrient content upon high precipitation intensities. For example, at 100% precipitation intensity, there was 32.6% more P and 33.2% more Ca in shoots, 40.6% more P and 45.4% more Ca in roots, and 37.9% more P and 82.3% more Ca in pods, as compared to those with pi treatment, respectively. No impact on soybean biomass was evident upon the application of nHA or pi. Further investigation into customizing nHA to enhance its affinity with crop leaves and to extend retention time on the leaf surface is warranted given that the present study did not show significant positive impacts of nHA on soybean growth under the effects of precipitation. Taken together, our findings increase understanding of the potential application of nHA as a nano-enabled fertilizer in sustainable agriculture

Wetland Degradation and Ecological Restoration

Wetlands are among the most important ecosystems on earth and functioned as the “kidneys” of the earth, which play an important role in maintaining ecological service functions. However, with the rapid growth in human populations, wetlands worldwide are suffering from serious degradation or loss as affected by wetland pollution, wetland reclamation, civilization and land use changes, and so forth. Wetland degradation has potential influences on human health, biodiversity, regional climate, and regional ecological security. Therefore, it is an urgent task to recover these degraded wetlands. In recent years, wetland protection, restoration, and its reasonable exploitation have been paid much more attention to by most governments and researchers. Moreover, wetland restoration has become the frontier fields of wetlands science, which has been listed as one of important themes in these recent international wetlands and ecological conferences. Understanding wetland degradation processes can contribute to better effective wetland restoration. Therefore, we organized this special issue on “wetland degradation and ecological restoration.” The objective of this special issue is to emphasize the effects of human activities on wetland ecosystems, the relationships between soil, water, and plant in wetlands, and wetland restoration issues and applications

Temporal and spatial distributions of soil nutrients in Hani terraced paddy fields, Southwestern China

AbstractHani terraced paddy fields are one of the most important ways for agricultural products and greatly influence regional landscapes in mountainous areas of Southwestern China. However, the knowledge of soil nutrient conditions from Hani terraced paddy fields is limited. This paper investigates such soil nutrient parameters as organic matter (OM), total nitrogen (TN), total phosphorus (TP), available phosphorus (AP), total potassium (TK), available potassium (AK) of four sampling sites of paddy fields under special geographical environment and agricultural technology, and compares the differences of soil nutrients related to spatial patterns and temporal periods. Correlation analysis is performed to analyze the impact of environmental factors on soil nutrients, as well as the relationships between soil nutrient parameters and altitude, slope direction, gradient and distance from village. The results show that there were some differences separately in the content of soil nutrients such as OM, TN, TP, AP, TK and AK. The AK and AP levels are lower in the fallow period than that in the tillage period, only OM level in the fallow period is higher than that in the tillage period; TN, TK, TP levels are nearly similar in the tillage and the fallow period. Unlike great differences in two periods, soil nutrient content in the ridge of fields is identical basically with the content in the corresponding paddy fields. Correlation analysis shows that soil nutrients of AK, TP, TN and OM have distinctive negative correlations with distance from villages, while AP and TK display a slight fluctuation

CpSmt3, an ortholog of small ubiquitin-like modifier, is essential for growth, organelle function, virulence, and antiviral defense in Cryphonectria parasitica

IntroductionSUMOylation is an important post-translational modification that regulates the expression, localization, and activity of substrate proteins, thereby participating in various important cellular processes such as the cell cycle, cell metabolism, gene transcription, and antiviral activity. However, the function of SUMOylation in phytopathogenic fungi has not yet been adequately explored.MethodsA comprehensive analysis composed of proteomics, affinity pull-down, molecular and cellular approaches was performed to explore the roles of SUMOylation in Cryphonectria parasitica, the fungal pathogen responsible for chestnut blight.Results and discussionCpSmt3, the gene encoding the SUMO protein CpSmt3 in C. parasitica was identified and characterized. Deletion of the CpSmt3 gene resulted in defects in mycelial growth and hyphal morphology, suppression of sporulation, attenuation of virulence, weakening of stress tolerance, and elevated accumulation of hypovirus dsRNA. The ΔCpSmt3 deletion mutant exhibited an increase in mitochondrial ROS, swollen mitochondria, excess autophagy, and thickened cell walls. About 500 putative SUMO substrate proteins were identified by affinity pull-down, among which many were implicated in the cell cycle, ribosome, translation, and virulence. Proteomics and SUMO substrate analyses further revealed that deletion of CpSmt3 reduced the accumulation of CpRho1, an important protein that is involved in TOR signal transduction. Silencing of CpRho1 resulted in a phenotype similar to that of ΔCpSmt3, while overexpression of CpRho1 could partly rescue some of the prominent defects in ΔCpSmt3. Together, these findings demonstrate that SUMOylation by CpSmt3 is vitally important and provide new insights into the SUMOylation-related regulatory mechanisms in C. parasitica

Mechanisms of Competitive Adsorption Organic Pollutants on Hexylene-Bridged Polysilsesquioxane

Hexylene-bridged periodic mesoporous polysilsesquioxanes (HBPMS) are a promising new class of adsorbent for the removal of organic contaminants from aqueous solutions. These hybrid organic-inorganic materials have a larger BET surface area of 897 m2·g−1 accessible through a cubic, isotropic network of 3.82-nm diameter pores. The hexylene bridging group provides enhanced adsorption of organic molecules while the bridged polysilsesquioxane structure permits sufficient silanols that are hydrophilic to be retained. In this study, adsorption of phenanthrene (PHEN), 2,4-Dichlorophenol (DCP), and nitrobenzene (NBZ) with HBPMS materials was studied to ascertain the relative contributions to adsorption performance from (1) direct competition for sites and (2) pore blockage. A conceptual model was proposed to further explain the phenomena. This study suggests a promising application of cubic mesoporous BPS in wastewater treatment