In this study,synthetic wastewater containing 110μg/L arsenate(As(V)),0-20 mg/L fulvic acid(FA),and 0-12.3 mg/L phosphate was treated with 3 mg/L Fe3+.The mechanisms of FA and phosphate effects on As(V)removal by fer...In this study,synthetic wastewater containing 110μg/L arsenate(As(V)),0-20 mg/L fulvic acid(FA),and 0-12.3 mg/L phosphate was treated with 3 mg/L Fe3+.The mechanisms of FA and phosphate effects on As(V)removal by ferric chloride were determined using 0.22-10μm pore-size filtration,Zetasizer analysis,and in situ flow through cell ATR-FTIR.The results showed that up to 20mg/L FA had almost no effect on the solubility of ferric hydroxide precipitates and adsorption of As(V)by the precipitates.When FA concentration increased from 0 to 20 mg/L,the adsorption of FA led to higher negative zeta potential of the precipitates and the strong electrostatic repulsion between the precipitates decreased the particle size of ferric hydroxide flocs fromlarger than 10μmto smaller than 1μm.In the presence of 5-20 mg/L FA,46%-63%As(V)was adsorbed onto the flocs with particle size in the range of 0.45-1μm.On the other hand,phosphate did not affect the size of ferric hydroxide flocs and significantly increased the dissolved As(V)concentration because it competed with As(V)for adsorption sites on ferric hydroxide precipitates.The addition of 5mg/L cationic organic flocculant significantly reduced the effect of FA on As(V)removal,but did not reduce the effect of phosphate on As(V)removal.The findings of this study will help develop effective arsenic treatment techniques and predict the mobility of arsenic in the environment.展开更多
Antibiotics present in surface water have detrimental effects on both human health and the ecosystem.Additionally,they pose a threat to the effectiveness of biological water treatment processes.In this study,a visible...Antibiotics present in surface water have detrimental effects on both human health and the ecosystem.Additionally,they pose a threat to the effectiveness of biological water treatment processes.In this study,a visible photocatalytic system with Bi OCl/g-C_(3)N_(4)heterojunction was developed to remove sulfonamide antibiotic sulfamerazine(SMZ)in water.The removal rate reached 92.77%under visible light irradiation for 80 min.This photocatalyst remained active after 5 cycles of experiments and maintained a relatively stable removal rate of SMZ of over 80%.The ESR tests indicate that the main active species in this photocatalytic system were h^(+)and^(·)O_(2)^(-).The enhanced photocatalytic efficiency was mainly ascribed to the formation of a built-in electric field between Bi OCl and g-C_(3)N_(4)through the carrier transport mechanism of the S-scheme heterojunction.This heterojunction facilitated the photogenerated carrier shift and segregation,and improved the interfacial charge transfer efficiency,as confirmed by photoelectrochemical test and Density functional theory(DFT)calculations.The HPLC-QTOF-MS/MS and DFT analysis revealed possible degradation pathways of SMZ may involve deamination,hydroxylation,SO_(2)extrusion and bond breaking.This novel Bi OCl/g-C_(3)N_(4)heterojunction has proven to be essential for efficient visible-light photocatalysis.展开更多
Biocementation is an emerging field within geotechnical engineering that focuses on harnessing microbiological activity to enhance the mechanical properties and behavior of rocks. It often relies on microbial-induced ...Biocementation is an emerging field within geotechnical engineering that focuses on harnessing microbiological activity to enhance the mechanical properties and behavior of rocks. It often relies on microbial-induced carbonate precipitation (MICP) or enzyme-induced carbonate precipitation (EICP) which utilizes biomineralization by promoting the generation of calcium carbonate (CaCO3) within the pores of geomaterials (rock and soil). However, there is still a lack of knowledge about the effect of porosity and bedding on biocementation in rocks from a mechanistic view. This experimental study investigated the impact of porosity and bedding orientations on the mechanical response of rocks due to biocementations, using two distinct biocementation strategies (MICP and EICP) and characteristically low porosity but interbedded rocks (shale) and more porous but non-bedded (dolostone) rocks. We first conducted biocementation treatments (MICP and EICP) of rock samples over a distinct period and temperature. Subsequently, the rock strength (uniaxial compressive strength, UCS) was measured. Finally, we analyzed the pre- and post-treatment changes in the rock samples to better understand the effect of MICP and EICP biocementations on the mechanical response of the rock samples. The results indicate that biocementations in dolostones can improve the rock mechanical integrity (EICP: +58% UCS;MICP: +25% UCS). In shales, biocementations can either slightly improve (EICP: +1% UCS) or weaken the rock mechanical integrity (MICP: -39% UCS). Further, results suggest that the major controlling mechanisms of biogeomechanical alterations due to MICP and EICP in rocks can be attributed to the inherent porosity, biocementation type, and bedding orientations, and in few cases the mechanisms can be swelling, osmotic suction, or pore pressurization. The findings in this study provide novel insights into the mechanical responses of rocks due to MICP and EICP biocementations.展开更多
Geothermal energy from deep underground (or geological) formations,with or without its combination with carbon capture and storage (CCS),can be a key technology to mitigate anthropogenic greenhouse gas emissions and m...Geothermal energy from deep underground (or geological) formations,with or without its combination with carbon capture and storage (CCS),can be a key technology to mitigate anthropogenic greenhouse gas emissions and meet the 2050 net‐zero carbon emission target.Geothermal resources in low‐permeability and medium‐and high‐temperature reservoirs in sedimentary sequence require hydraulic stimulation for enhanced geothermal systems (EGS).However,fluid migration for geothermal energy in EGS or with potential CO_(2) storage in a CO_(2)‐EGS are both dependent on the in situ flow pathway network created by induced fluid injection.These thermo‐mechanical interactions can be complex and induce varying alterations in the mechanical response when the working fluid is water (in EGS) or supercritical CO_(2)(in CO_(2)‐EGS),which could impact the geothermal energy recovery from geological formations.Therefore,there is a need for a deeper understanding of the heat extraction process in EGS and CO_(2)‐EGS.This study presents a systematic review of the effects of changes in mechanical properties and behavior of deep underground rocks on the induced flow pathway and heat recovery in EGS reservoirs with or without CO_(2) storage in CO_(2) ‐EGS.Further,we proposed waterless‐stimulated EGS as an alternative approach to improve heat energy extraction in EGS.Lastly,based on the results of our literature review and proposed ideas,we recommend promising areas of investigation that may provide more insights into understanding geothermo‐mechanics to further stimulate new research studies and accelerate the development of geothermal energy as a viable clean energy technology.展开更多
As a major mode choice of commuters for daily travel, bus transit plays an important role in many urban and metropolitan areas. This work proposes a mathematical model to optimize bus service by minimizing total cost ...As a major mode choice of commuters for daily travel, bus transit plays an important role in many urban and metropolitan areas. This work proposes a mathematical model to optimize bus service by minimizing total cost and considering a temporally and directionally variable demand. An integrated bus service, consisting of all-stop and stop-skipping services is proposed and optimized subject to directional frequency conservation, capacity and operable fleet size constraints. Since the research problem is a combinatorial optimization problem, a genetic algorithm is developed to search for the optimal result in a large solution space. The model was successfully implemented on a bus transit route in the City of Chengdu, China, and the optimal solution was proved to be better than the original operation in terms of total cost. The sensitivity of model parameters to some key attributes/variables is analyzed and discussed to explore further the potential of accruing additional benefits or avoiding some of the drawbacks of stop-skipping services.展开更多
Compromised integrity of cementitious materials can lead to potential geo-hazards such as detrimental fluid flow to the wellbore(borehole),potential leakage of underground stored fluids,contamination of water aquifers...Compromised integrity of cementitious materials can lead to potential geo-hazards such as detrimental fluid flow to the wellbore(borehole),potential leakage of underground stored fluids,contamination of water aquifers,and other issues that could impact environmental sustainability during underground construction operations.The mechanical integrity of wellbore cementitious materials is critical to prevent wellbore failure and leakages,and thus,it is imperative to understand and predict the integrity of oilwell cement(OWC)and microbial-induced calcite precipitation(MICP)to maintain wellbore integrity and ensure zonal isolation at depth.Here,we investigated the mechanical integrity of two cementitious materials(MICP and OWC),and assessed their potential for plugging leakages around the wellbore.Further,we applied Machine Learning(ML)models to upscale and predict near-wellbore mechanical integrity at macro-scale by adopting two ML algorithms,Artificial Neural Network(ANN)and Random Forest(RF),using 100 datasets(containing 100 observations).Fractured portions of rock specimens were treated with MICP and OWC,respectively,and their resultant mechanical integrity(unconfined compressive strength,UCS;fracture toughness,K_(s))were evaluated using experimental mechanical tests and ML models.The experimental results showed that although OWC(average UCS=97 MPa,K_(s)=4.3 MPa·√m)has higher mechanical integrity over MICP(average UCS=86 MPa,K_(s)=3.6 MPa·√m),the MICP showed an edge over OWC in sealing microfractures and micro-leakage pathways.Also,the OWC can provide a greater near-wellbore seal than MICP for casing-cement or cement-formation delamination with relatively greater mechanical integrity.The results show that the degree of correlation between the mechanical integrity obtained from lab tests and the ML predictions is high.The best ML algorithm to predict the macro-scale mechanical integrity of a MICP-cemented specimen is the RF model(R^(2)for UCS=0.9738 and K_(s)=0.9988;MAE for UCS=1.04 MPa and K_(s)=0.02 MPa·√m).Similarly,for OWC-cemented specimen,the best ML algorithm to predict their macro-scale mechanical integrity is the RF model(R^(2)for UCS=0.9984 and K_(s)=0.9996;MAE for UCS=0.5 MPa and K_(s)=0.01 MPa·√m).This study provides insights into the potential of MICP and OWC as near-wellbore ce-mentitious materials and the applicability of ML model for evaluating and predicting the mechanical integrity of cementitious materials used in near-wellbore to achieve efficient geo-hazard mitigation and environmental protection in engineering and underground operations.展开更多
This paper presents vehicle localization and tracking methodology to utilize two-channel LiDAR data for turning movement counts. The proposed methodology uniquely integrates a K-means clustering technique, an inverse ...This paper presents vehicle localization and tracking methodology to utilize two-channel LiDAR data for turning movement counts. The proposed methodology uniquely integrates a K-means clustering technique, an inverse sensor model, and a Kalman filter to obtain the final trajectories of an individual vehicle. The objective of applying K-means clustering is to robustly differentiate LiDAR data generated by pedestrians and multiple vehicles to identify their presence in the LiDAR’s field of view (FOV). To localize the detected vehicle, an inverse sensor model was used to calculate the accurate location of the vehicles in the LiDAR’s FOV with a known LiDAR position. A constant velocity model based Kalman filter is defined to utilize the localized vehicle information to construct its trajectory by combining LiDAR data from the consecutive scanning cycles. To test the accuracy of the proposed methodology, the turning movement data was collected from busy intersections located in Newark, NJ. The results show that the proposed method can effectively develop the trajectories of the turning vehicles at the intersections and has an average accuracy of 83.8%. Obtained R-squared value for localizing the vehicles ranges from 0.87 to 0.89. To measure the accuracy of the proposed method, it is compared with previously developed methods that focused on the application of multiple-channel LiDARs. The comparison shows that the proposed methodology utilizes two-channel LiDAR data effectively which has a low resolution of data cluster and can achieve acceptable accuracy compared to multiple-channel LiDARs and therefore can be used as a cost-effective measure for large-scale data collection of smart cities.展开更多
Highly ductile cement-based materials have emerged as alternatives to conventional concrete materials to improve the seismic resistance of reinforced concrete(RC)structures.While experimental and numerical research on...Highly ductile cement-based materials have emerged as alternatives to conventional concrete materials to improve the seismic resistance of reinforced concrete(RC)structures.While experimental and numerical research on the behavior of individual components has provided significant knowledge on element-level response,relatively little is known about how ductile cement-based materials influence system-level behavior in seismic applications.This study uses recently developed lumped-plasticity models to simulate the unique failure characteristics and ductility of reinforced ductile-cement-based materials in beam hinges and applies them in the assessment of archetype frame structures.Numerous story heights(four,eight,and twelve),frame configurations(perimeter vs.space),materials(conventional vs.ductile concrete),and replacement mechanisms within the beam hinges are considered in the seismic analysis of the archetype structures.Results and comparisons are made in terms of the probability of collapse at 2%in 50-year ground motion,mean annual frequency of collapse,and adjusted collapse margin ratio(ACMR)across archetype structures.The results show that engineered HPFRCCs in beam plastic-hinge regions can improve the seismic safety of moment frame buildings with higher collapse margin ratios,lower probability of collapse,and the ability to withstand large deformations.Data is also reported on how ductile concrete materials can reduce concrete volume and longitudinal reinforcement tonnage across frame configurations and story heights while maintaining or improving seismic resistance of the structural system.Results demonstrate future research needs to assess life-cycle costs,predict column hinge behavior,and develop code-based design methods for structural systems using highly ductile concrete materials.展开更多
Rocks can deform at varying scales(nano-,micro-and macro-scale)under different temperatures,pressures,stresses,and time conditions.Sub-core scale(nano-to micro-scale)changes in rock properties can influence local(fine...Rocks can deform at varying scales(nano-,micro-and macro-scale)under different temperatures,pressures,stresses,and time conditions.Sub-core scale(nano-to micro-scale)changes in rock properties can influence local(fine-scale)and bulk scale(macro-scale)rock deformation.However,there is a lack of comprehensive knowledge on how rock deformation at sub-core scale(i.e.,nano-to micro-scale)is assessed and its potential to accurately predicte and estimate the macro-scale mechanical behavior of rocks.This study presents a comprehensive and forward-leaning review of the assessment of nano-scale and micro-scale rock mechanical parameters,their timedependent behavior,and potential applications in rock engineering.Also,we highlighted the key findings based on experimental and numerical methods for evaluating rock mechanical parameters,and presented the limitations of these approaches.Further,we discussed the reliability of sub-core scale mechanical assessments in predicting macromechanical(larger-scale)properties and the behavior of rocks in geo-engineering.Finally,we offer recommendations to advance investigations focused on rock mechanical assessments at these smaller scales and provide a more accurate characterization at the sub-core scale.展开更多
Organic-rich shales have gained significant attention in recent years due to their pivotal role in unconventional hydrocarbon production.These shale rocks undergo thermal maturation processes that alter their mechanic...Organic-rich shales have gained significant attention in recent years due to their pivotal role in unconventional hydrocarbon production.These shale rocks undergo thermal maturation processes that alter their mechanical properties,making their study essential for subsurface operations.However,characterizing the mechanical properties of organic-rich shale is often challenging due to its multiscale nature and complex composition.This work aims to bridge that knowledge gap to fully understand the nanomechanical properties of Shale organic matter at various thermal maturation stages.This study employs PeakForce Quantitative Nanomechanical Map-ping(PF-QNM)using Atomic Force Microscopy(AFM)to investigate how changes at the immature,early mature,and peak mature stages impact the mechanical properties of the Bakken Shale organic matter.PF-QNM provides reliable mechanical measurements,allowing for the quantification and qualification of shale constituents'elastic modulus(E).We also accounted for the effect of probe type and further analyzed the impact of probe wear on the nanomechanical properties of shale organic matter.In immature shale,the average elastic modulus of organic matter is approximately 6 GPa,whereas in early mature and peak mature shale,it decreases to 5.5 GPa and 3.8 GPa,respectively.Results reveal a mechanical degradation with increasing thermal maturation,as evidenced by a reduction in Young's modulus(E).Specifically,the immature shale exhibits an 8%reduction in E,while the early mature and peak mature shales experience more substantial reductions of 31%and 37%,respectively.This phenomenon could be attributed to the surface probing of low-modulus materials like bitumen generated during heating.The findings underscore the potential of AFM PF-QNM for assessing the nanomechanical characteristics of complex and heterogeneous rocks like shales.However,it also highlights the need for standardized mea-surement practices,considering the diverse components in these rocks and their different elastic moduli.展开更多
Magnetotactic bacteria(MTB)are a group of Gram-negative prokaryotes that respond to the geomagnetic field.This unique property is attributed to the intracellular magnetosomes,which contains membrane-bound nanocrystals...Magnetotactic bacteria(MTB)are a group of Gram-negative prokaryotes that respond to the geomagnetic field.This unique property is attributed to the intracellular magnetosomes,which contains membrane-bound nanocrystals of magnetic iron minerals.This review summarizes the most recent advances in MTB,magnetosomes,and their potential applications especially the environmental pollutant control or remediation.The morphologic and phylogenetic diversity of MTB were first introduced,followed by a critical review of isolation and cultivation methods.Researchers have devoted to optimize the factors,such as oxygen,carbon source,nitrogen source,nutrient broth,iron source,and mineral elements for the growth of MTB.Besides the applications of MTB in modem biological and medical fields,little attention was made on the environmental applications of MTB for wastewater treatment,which has been summarized in this review.For example,applications of MTB as adsorbents have resulted in a novel magnetic separation technology for removal of heavy metals or organic pollutants in wastewater.In addition,we summarized the current advance on pathogen removal and detection of endocrine disruptor which can inspire new insights toward sustainable engineering and practices.Finally,the new perspectives and possible directions for future studies are recommended,such as isolation of MTB.genetic modification of MTB for mass production and new environmental applications.The ultimate objective of this review is to promote the applications of MTB and magnetosomes in the environmental fields.展开更多
To develop highly effective adsorbents for chromium removal,a nitrogen-doped biomass-derived carbon(NHPC)was synthesized via direct carbonation of loofah sponge followed by alkali activation and doping modification.NH...To develop highly effective adsorbents for chromium removal,a nitrogen-doped biomass-derived carbon(NHPC)was synthesized via direct carbonation of loofah sponge followed by alkali activation and doping modification.NHPC possessed a hierarchical micro-/mesoporous lamellar structure with nitrogen-containing functional groups(1.33 at%),specific surface area(1792.47 m2/g),and pore volume(1.18 cm^(3)/g).NHPC exhibited a higher Cr(Ⅵ)adsorption affinity than the HPC(without nitrogen doping)or the pristine loofah sponge carbon(LSC)did.The influence of process parameters,including pH,dosage,time,temperature,and Cr(Ⅵ)concentration,on Cr(Ⅵ)adsorption by NHPC were evaluated.The Cr(Ⅵ)adsorption kinetics matched with the pseudo-second-order model(R^(2)≥0.9983).The Cr(Ⅵ)adsorption isotherm was fitted with the Langmuir isotherm model,which indicated the maximum Cr(Ⅵ)adsorption capacities:227.27,238.10,and 285.71 mg/g at 298K,308K,and 318K,respectively.The model analysis also indicated that adsorption of Cr(Ⅵ)on NHPC was a spontaneous,endothermal,and entropy-increasing process.The Cr(Ⅵ)adsorption process potentially involved mixed reductive and adsorbed mechanism.Furthermore,computational chemistry calculations revealed that the adsorption energy between NHPC and Cr(VI)(-0.84 eV)was lower than that of HPC(-0.51 eV),suggesting that nitrogen doping could greatly enhance the interaction between NHPC and Cr(VI).展开更多
The present study evaluated a photo-Fenton reactive membrane that achieved enhanced 1,4-Dioxane removal performance.As a common organic solvent and stabilizer,1,4-Dioxane is widely used in a variety of industrial prod...The present study evaluated a photo-Fenton reactive membrane that achieved enhanced 1,4-Dioxane removal performance.As a common organic solvent and stabilizer,1,4-Dioxane is widely used in a variety of industrial products and poses negative environmental and health impacts.The membrane was prepared by covalently coating photocatalyst of goethite(α-FeOOH)on a ceramic porous membrane as we reported previously.The effects of UV irradiation,H_(2)O_(2)and catalyst on the removal efficiency of 1,4-Dioxane in batch reactors were first evaluated for optimized reaction conditions,followed by a systematical investigation of 1,4-Dioxane removal in the photo-Fenton membrane filtration mode.Under optimized conditions,the 1,4-Dioxane removal rate reached up to 16%with combination of 2 mmol/L H_(2)O_(2)and UV365 irradiation(2000µW/cm^(2))when the feed water was filtered by the photo-Fenton reactive membrane at a hydraulic retention time of 6 min.The removal efficiency and apparent quantum yield(AQY)were both enhanced in the filtration compared to the batch mode of the same photo-Fenton reaction.Moreover,the proposed degradation pathways were analyzed by density functional theory(DFT)calculations,which provided a new insight into the degradation mechanisms of 1,4-Dioxane in photo-Fenton reactions on the functionalized ceramic membrane.展开更多
Shale reservoirs have been a significant focus of hydrocarbon production over the past few decades,and the mechanical assessment of target shale reservoirs has been critical to successful field operations,especially i...Shale reservoirs have been a significant focus of hydrocarbon production over the past few decades,and the mechanical assessment of target shale reservoirs has been critical to successful field operations,especially in hydraulic fracturing and well completions.The Unconfined compressive strength(UCS)and Poisson's ratio(ν)are critical mechanical properties in shale reservoir assessment.The estimation and measurement of shale mechanical properties are often erroneous by not accounting for their heterogeneous and pre-existing features,which yield variability of shale mechanical properties along their lithostratigraphy.Thus,there is a need to investigate the degree of correlation and accuracy in multiscale mechanical evaluations of heterogeneous shales,and the correlation between such micromechanical and macromechanical measurements.This study investigated the impact of inherent heterogeneity on the measurement of continuous micromechanical and macromechanical properties of shale reservoirs using scratch test(ST)and uniaxial compression test(UCT)methods,and the degree of correlation(correlation coefficient,r)of measurements in shale was further assessed for the variability of their measured properties.Shale core samples from three distinct shale formations were utilized and studied,and the core samples were subjected to ST and UCT,respectively.The results from this study showed that despite inherent heterogeneous anomalies and natural fractures in the shale samples analyzed,there is a good degree of correlation(UCS:r=0.73;ν:r=0.89)in the micro-and macro-mechanical properties of shales using two independent experimental tests(ST and UCT).This study provides insights for improving the accuracy of mechanical evaluations and numerical modeling in shales with a high degree of heterogeneity and pre-existing natural fractures.The results indicate that when considering the structural complexity and heterogeneity of unconventional reservoirs such as shales,the ST method can provide a better continuous micromechanical assessment of shales.In contrast,the UCT can provide a better bulk macromechanical measurement of shales.展开更多
Plastic pollution has been a legacy environment problems and more recently,the plastic particles,especially those ultrafine or small plastics particles,are widely recognized with increasing environmental and ecologica...Plastic pollution has been a legacy environment problems and more recently,the plastic particles,especially those ultrafine or small plastics particles,are widely recognized with increasing environmental and ecological impacts.Among small plastics,microplastics are intensively studied,whereas the physicochemical properties,environmental abundance,chemical states,bioavailability and toxicity toward organisms of nanoplastics are inadequately investigated.There are substantial difficulties in separation,visualization and chemical identification of nanoplastics due to their small sizes,relatively low concentrations and interferences from coexisting substances(e.g.,dyes or natural organic matters).Moreover,detection of polymers at nanoscale is largely hampered by the detection limit or sensitivity for existing spectral techniques such as Transformed Infrared Spectroscopy(FTIR)or Raman Spectroscopy.This article critically examined the current state of art techniques that are exclusively reported for nanoplastic characterization in environmental samples.Based on their operation principles,potential applications and limitations of these analytical techniques are carefully analyzed.展开更多
Breaker fluids are designed to dissolve filter cakes by breaking their long-chain molecules,thereby removing solid deposits on the wellbore wall.Although breaker fluids are not intended to infiltrate the hydrocarbon r...Breaker fluids are designed to dissolve filter cakes by breaking their long-chain molecules,thereby removing solid deposits on the wellbore wall.Although breaker fluids are not intended to infiltrate the hydrocarbon reservoir,they can invade and cause formation damage by altering sandstone reservoirs'wettability and relative permeability.This can lead to a reduction in the overall reservoir performance.This study coupled tripartite methods to investigate the potential impact of breaker invasion and transport in hydrocarbon reservoirs and its multiscale effect on the performances of sandstone reservoirs.We utilized experimental,analytical,and numerical methods to assess and predict the susceptibility of reservoirs to breaker fluid invasion and transportation.Our experimental and empirical investigations considered varying breaker fluid formulations to evaluate the effects of breaker fluid concentration,formation temperature,and solution gas-oil ratio(GOR)on residual-oil saturation(ROS)and oil-water relative permeability.By adopting the ROS and relative permeability associated with the 50%v/v breaker fluid mixture,the performance of the hydrocarbon reservoir was numerically simulated under the limiting scenarios of no-invasion,moderate-invasion,and deep-invasion of breaker fluid.The results indicate a positive correlation between breaker fluid concentration and ROS,highlighting the risks that breaker fluid invasion and deep infiltration pose to hydrocarbon recovery.Further,results show that both live-oil condition(LOC)and dead-oil condition(DOC)reservoirs are susceptible to the detrimental impacts of breaker fluid infiltration,while their invasion can reduce hydrocarbon recovery in both LOC(-6%)and DOC(-28%).The multi-scale effects on reservoir performance are more pronounced at near-wellbore and DOC than at far-field and LOC.Findings from this work provide valuable insights into the complexity of breaker-fluid invasion in sandstone reservoirs and the mitigation of associated risks to reservoir performance.展开更多
This study evaluated the physiological characteristics(e.g.,growth parameters,chlorophyll content,metabolites and antioxidative enzymes activity)of Alternanthera philoxeroides(A.philoxeroides),as a hyperaccumulator pl...This study evaluated the physiological characteristics(e.g.,growth parameters,chlorophyll content,metabolites and antioxidative enzymes activity)of Alternanthera philoxeroides(A.philoxeroides),as a hyperaccumulator plant,during the phytoremediation of cadmium(Cd)from water.After cultivating A.philoxeroides in a Cd-containing medium for 30 days,the growth rate was inhibited by up to 33.5%as the exposed Cd concentration increased to 0.80 mmol·L−1.Cd exposure interfered with the photosynthesis of A.philoxeroides and caused oxidative stress as indicated by the rise of malondialdehyde(MDA)and H2O2,which increased by 8 times and 3 times compared to the control group.Moreover,high exposure concentrations of Cd also reduced the activities of multiple antioxidants(e.g.,GSH and AsA),indicating the inhibition of Cd on the plant’s ability to mitigate oxidative damage.Finally,the fluorescent patterns of the rhizosphere dissolved organic matter(rDOM)revealed three major components(humic,fulvic substances and protein-like substances)well correlated with the changes in antioxidant activities.Partial least-squares discriminant analysis(PLS-DA)visualized the difference in the activity of the antioxidative enzymes between different groups.The study unravelled deep insights into the potential mechanisms of tolerance and resistance of A.philoxeroides for phytoremediation of Cd pollution.展开更多
基金financially supported by the New Jersey Department of Environmental ProtectionUS EPA。
文摘In this study,synthetic wastewater containing 110μg/L arsenate(As(V)),0-20 mg/L fulvic acid(FA),and 0-12.3 mg/L phosphate was treated with 3 mg/L Fe3+.The mechanisms of FA and phosphate effects on As(V)removal by ferric chloride were determined using 0.22-10μm pore-size filtration,Zetasizer analysis,and in situ flow through cell ATR-FTIR.The results showed that up to 20mg/L FA had almost no effect on the solubility of ferric hydroxide precipitates and adsorption of As(V)by the precipitates.When FA concentration increased from 0 to 20 mg/L,the adsorption of FA led to higher negative zeta potential of the precipitates and the strong electrostatic repulsion between the precipitates decreased the particle size of ferric hydroxide flocs fromlarger than 10μmto smaller than 1μm.In the presence of 5-20 mg/L FA,46%-63%As(V)was adsorbed onto the flocs with particle size in the range of 0.45-1μm.On the other hand,phosphate did not affect the size of ferric hydroxide flocs and significantly increased the dissolved As(V)concentration because it competed with As(V)for adsorption sites on ferric hydroxide precipitates.The addition of 5mg/L cationic organic flocculant significantly reduced the effect of FA on As(V)removal,but did not reduce the effect of phosphate on As(V)removal.The findings of this study will help develop effective arsenic treatment techniques and predict the mobility of arsenic in the environment.
基金supported by the National Natural Science Foundation of China(No.52370174)the Natural Science Foundation of Shandong Province,China(No.ZR2022ME128)+1 种基金Special Projects in Key Areas of Colleges and Universities in Guangdong Province(No.2023ZDZX4050)Talents of High-Level Scientific Research Foundation of Qingdao Agricultural University(No.6651120004)。
文摘Antibiotics present in surface water have detrimental effects on both human health and the ecosystem.Additionally,they pose a threat to the effectiveness of biological water treatment processes.In this study,a visible photocatalytic system with Bi OCl/g-C_(3)N_(4)heterojunction was developed to remove sulfonamide antibiotic sulfamerazine(SMZ)in water.The removal rate reached 92.77%under visible light irradiation for 80 min.This photocatalyst remained active after 5 cycles of experiments and maintained a relatively stable removal rate of SMZ of over 80%.The ESR tests indicate that the main active species in this photocatalytic system were h^(+)and^(·)O_(2)^(-).The enhanced photocatalytic efficiency was mainly ascribed to the formation of a built-in electric field between Bi OCl and g-C_(3)N_(4)through the carrier transport mechanism of the S-scheme heterojunction.This heterojunction facilitated the photogenerated carrier shift and segregation,and improved the interfacial charge transfer efficiency,as confirmed by photoelectrochemical test and Density functional theory(DFT)calculations.The HPLC-QTOF-MS/MS and DFT analysis revealed possible degradation pathways of SMZ may involve deamination,hydroxylation,SO_(2)extrusion and bond breaking.This novel Bi OCl/g-C_(3)N_(4)heterojunction has proven to be essential for efficient visible-light photocatalysis.
文摘Biocementation is an emerging field within geotechnical engineering that focuses on harnessing microbiological activity to enhance the mechanical properties and behavior of rocks. It often relies on microbial-induced carbonate precipitation (MICP) or enzyme-induced carbonate precipitation (EICP) which utilizes biomineralization by promoting the generation of calcium carbonate (CaCO3) within the pores of geomaterials (rock and soil). However, there is still a lack of knowledge about the effect of porosity and bedding on biocementation in rocks from a mechanistic view. This experimental study investigated the impact of porosity and bedding orientations on the mechanical response of rocks due to biocementations, using two distinct biocementation strategies (MICP and EICP) and characteristically low porosity but interbedded rocks (shale) and more porous but non-bedded (dolostone) rocks. We first conducted biocementation treatments (MICP and EICP) of rock samples over a distinct period and temperature. Subsequently, the rock strength (uniaxial compressive strength, UCS) was measured. Finally, we analyzed the pre- and post-treatment changes in the rock samples to better understand the effect of MICP and EICP biocementations on the mechanical response of the rock samples. The results indicate that biocementations in dolostones can improve the rock mechanical integrity (EICP: +58% UCS;MICP: +25% UCS). In shales, biocementations can either slightly improve (EICP: +1% UCS) or weaken the rock mechanical integrity (MICP: -39% UCS). Further, results suggest that the major controlling mechanisms of biogeomechanical alterations due to MICP and EICP in rocks can be attributed to the inherent porosity, biocementation type, and bedding orientations, and in few cases the mechanisms can be swelling, osmotic suction, or pore pressurization. The findings in this study provide novel insights into the mechanical responses of rocks due to MICP and EICP biocementations.
文摘Geothermal energy from deep underground (or geological) formations,with or without its combination with carbon capture and storage (CCS),can be a key technology to mitigate anthropogenic greenhouse gas emissions and meet the 2050 net‐zero carbon emission target.Geothermal resources in low‐permeability and medium‐and high‐temperature reservoirs in sedimentary sequence require hydraulic stimulation for enhanced geothermal systems (EGS).However,fluid migration for geothermal energy in EGS or with potential CO_(2) storage in a CO_(2)‐EGS are both dependent on the in situ flow pathway network created by induced fluid injection.These thermo‐mechanical interactions can be complex and induce varying alterations in the mechanical response when the working fluid is water (in EGS) or supercritical CO_(2)(in CO_(2)‐EGS),which could impact the geothermal energy recovery from geological formations.Therefore,there is a need for a deeper understanding of the heat extraction process in EGS and CO_(2)‐EGS.This study presents a systematic review of the effects of changes in mechanical properties and behavior of deep underground rocks on the induced flow pathway and heat recovery in EGS reservoirs with or without CO_(2) storage in CO_(2) ‐EGS.Further,we proposed waterless‐stimulated EGS as an alternative approach to improve heat energy extraction in EGS.Lastly,based on the results of our literature review and proposed ideas,we recommend promising areas of investigation that may provide more insights into understanding geothermo‐mechanics to further stimulate new research studies and accelerate the development of geothermal energy as a viable clean energy technology.
基金Project(B01B1203)supported by Sichuan Province Key Laboratory of Comprehensive Transportation,ChinaProject(SWJTU09BR141)supported by the Southwest Jiaotong University,China
文摘As a major mode choice of commuters for daily travel, bus transit plays an important role in many urban and metropolitan areas. This work proposes a mathematical model to optimize bus service by minimizing total cost and considering a temporally and directionally variable demand. An integrated bus service, consisting of all-stop and stop-skipping services is proposed and optimized subject to directional frequency conservation, capacity and operable fleet size constraints. Since the research problem is a combinatorial optimization problem, a genetic algorithm is developed to search for the optimal result in a large solution space. The model was successfully implemented on a bus transit route in the City of Chengdu, China, and the optimal solution was proved to be better than the original operation in terms of total cost. The sensitivity of model parameters to some key attributes/variables is analyzed and discussed to explore further the potential of accruing additional benefits or avoiding some of the drawbacks of stop-skipping services.
文摘Compromised integrity of cementitious materials can lead to potential geo-hazards such as detrimental fluid flow to the wellbore(borehole),potential leakage of underground stored fluids,contamination of water aquifers,and other issues that could impact environmental sustainability during underground construction operations.The mechanical integrity of wellbore cementitious materials is critical to prevent wellbore failure and leakages,and thus,it is imperative to understand and predict the integrity of oilwell cement(OWC)and microbial-induced calcite precipitation(MICP)to maintain wellbore integrity and ensure zonal isolation at depth.Here,we investigated the mechanical integrity of two cementitious materials(MICP and OWC),and assessed their potential for plugging leakages around the wellbore.Further,we applied Machine Learning(ML)models to upscale and predict near-wellbore mechanical integrity at macro-scale by adopting two ML algorithms,Artificial Neural Network(ANN)and Random Forest(RF),using 100 datasets(containing 100 observations).Fractured portions of rock specimens were treated with MICP and OWC,respectively,and their resultant mechanical integrity(unconfined compressive strength,UCS;fracture toughness,K_(s))were evaluated using experimental mechanical tests and ML models.The experimental results showed that although OWC(average UCS=97 MPa,K_(s)=4.3 MPa·√m)has higher mechanical integrity over MICP(average UCS=86 MPa,K_(s)=3.6 MPa·√m),the MICP showed an edge over OWC in sealing microfractures and micro-leakage pathways.Also,the OWC can provide a greater near-wellbore seal than MICP for casing-cement or cement-formation delamination with relatively greater mechanical integrity.The results show that the degree of correlation between the mechanical integrity obtained from lab tests and the ML predictions is high.The best ML algorithm to predict the macro-scale mechanical integrity of a MICP-cemented specimen is the RF model(R^(2)for UCS=0.9738 and K_(s)=0.9988;MAE for UCS=1.04 MPa and K_(s)=0.02 MPa·√m).Similarly,for OWC-cemented specimen,the best ML algorithm to predict their macro-scale mechanical integrity is the RF model(R^(2)for UCS=0.9984 and K_(s)=0.9996;MAE for UCS=0.5 MPa and K_(s)=0.01 MPa·√m).This study provides insights into the potential of MICP and OWC as near-wellbore ce-mentitious materials and the applicability of ML model for evaluating and predicting the mechanical integrity of cementitious materials used in near-wellbore to achieve efficient geo-hazard mitigation and environmental protection in engineering and underground operations.
文摘This paper presents vehicle localization and tracking methodology to utilize two-channel LiDAR data for turning movement counts. The proposed methodology uniquely integrates a K-means clustering technique, an inverse sensor model, and a Kalman filter to obtain the final trajectories of an individual vehicle. The objective of applying K-means clustering is to robustly differentiate LiDAR data generated by pedestrians and multiple vehicles to identify their presence in the LiDAR’s field of view (FOV). To localize the detected vehicle, an inverse sensor model was used to calculate the accurate location of the vehicles in the LiDAR’s FOV with a known LiDAR position. A constant velocity model based Kalman filter is defined to utilize the localized vehicle information to construct its trajectory by combining LiDAR data from the consecutive scanning cycles. To test the accuracy of the proposed methodology, the turning movement data was collected from busy intersections located in Newark, NJ. The results show that the proposed method can effectively develop the trajectories of the turning vehicles at the intersections and has an average accuracy of 83.8%. Obtained R-squared value for localizing the vehicles ranges from 0.87 to 0.89. To measure the accuracy of the proposed method, it is compared with previously developed methods that focused on the application of multiple-channel LiDARs. The comparison shows that the proposed methodology utilizes two-channel LiDAR data effectively which has a low resolution of data cluster and can achieve acceptable accuracy compared to multiple-channel LiDARs and therefore can be used as a cost-effective measure for large-scale data collection of smart cities.
基金supported by the National Science Foundation under Grant No.2141955.Any opinions,findings,conclusions,or recommendations expressed in this material are those of the author(s)and do not necessarily reflect the views of the National Science Foundation.The authors also gratefully acknowledge support from the John A.Reif,Jr.Department of Civil and Environmental Engineering at New Jersey Institute of Technology.
文摘Highly ductile cement-based materials have emerged as alternatives to conventional concrete materials to improve the seismic resistance of reinforced concrete(RC)structures.While experimental and numerical research on the behavior of individual components has provided significant knowledge on element-level response,relatively little is known about how ductile cement-based materials influence system-level behavior in seismic applications.This study uses recently developed lumped-plasticity models to simulate the unique failure characteristics and ductility of reinforced ductile-cement-based materials in beam hinges and applies them in the assessment of archetype frame structures.Numerous story heights(four,eight,and twelve),frame configurations(perimeter vs.space),materials(conventional vs.ductile concrete),and replacement mechanisms within the beam hinges are considered in the seismic analysis of the archetype structures.Results and comparisons are made in terms of the probability of collapse at 2%in 50-year ground motion,mean annual frequency of collapse,and adjusted collapse margin ratio(ACMR)across archetype structures.The results show that engineered HPFRCCs in beam plastic-hinge regions can improve the seismic safety of moment frame buildings with higher collapse margin ratios,lower probability of collapse,and the ability to withstand large deformations.Data is also reported on how ductile concrete materials can reduce concrete volume and longitudinal reinforcement tonnage across frame configurations and story heights while maintaining or improving seismic resistance of the structural system.Results demonstrate future research needs to assess life-cycle costs,predict column hinge behavior,and develop code-based design methods for structural systems using highly ductile concrete materials.
文摘Rocks can deform at varying scales(nano-,micro-and macro-scale)under different temperatures,pressures,stresses,and time conditions.Sub-core scale(nano-to micro-scale)changes in rock properties can influence local(fine-scale)and bulk scale(macro-scale)rock deformation.However,there is a lack of comprehensive knowledge on how rock deformation at sub-core scale(i.e.,nano-to micro-scale)is assessed and its potential to accurately predicte and estimate the macro-scale mechanical behavior of rocks.This study presents a comprehensive and forward-leaning review of the assessment of nano-scale and micro-scale rock mechanical parameters,their timedependent behavior,and potential applications in rock engineering.Also,we highlighted the key findings based on experimental and numerical methods for evaluating rock mechanical parameters,and presented the limitations of these approaches.Further,we discussed the reliability of sub-core scale mechanical assessments in predicting macromechanical(larger-scale)properties and the behavior of rocks in geo-engineering.Finally,we offer recommendations to advance investigations focused on rock mechanical assessments at these smaller scales and provide a more accurate characterization at the sub-core scale.
文摘Organic-rich shales have gained significant attention in recent years due to their pivotal role in unconventional hydrocarbon production.These shale rocks undergo thermal maturation processes that alter their mechanical properties,making their study essential for subsurface operations.However,characterizing the mechanical properties of organic-rich shale is often challenging due to its multiscale nature and complex composition.This work aims to bridge that knowledge gap to fully understand the nanomechanical properties of Shale organic matter at various thermal maturation stages.This study employs PeakForce Quantitative Nanomechanical Map-ping(PF-QNM)using Atomic Force Microscopy(AFM)to investigate how changes at the immature,early mature,and peak mature stages impact the mechanical properties of the Bakken Shale organic matter.PF-QNM provides reliable mechanical measurements,allowing for the quantification and qualification of shale constituents'elastic modulus(E).We also accounted for the effect of probe type and further analyzed the impact of probe wear on the nanomechanical properties of shale organic matter.In immature shale,the average elastic modulus of organic matter is approximately 6 GPa,whereas in early mature and peak mature shale,it decreases to 5.5 GPa and 3.8 GPa,respectively.Results reveal a mechanical degradation with increasing thermal maturation,as evidenced by a reduction in Young's modulus(E).Specifically,the immature shale exhibits an 8%reduction in E,while the early mature and peak mature shales experience more substantial reductions of 31%and 37%,respectively.This phenomenon could be attributed to the surface probing of low-modulus materials like bitumen generated during heating.The findings underscore the potential of AFM PF-QNM for assessing the nanomechanical characteristics of complex and heterogeneous rocks like shales.However,it also highlights the need for standardized mea-surement practices,considering the diverse components in these rocks and their different elastic moduli.
基金This study was supported by the National Natural Science Foundation of China(Grant No.21677015)the Innovative Research Group of the National Natural Science Foundation of China(No.51721093)the US national science foundation(No.1756444)via Biological&Environmental Interfaces of Nano Materials.
文摘Magnetotactic bacteria(MTB)are a group of Gram-negative prokaryotes that respond to the geomagnetic field.This unique property is attributed to the intracellular magnetosomes,which contains membrane-bound nanocrystals of magnetic iron minerals.This review summarizes the most recent advances in MTB,magnetosomes,and their potential applications especially the environmental pollutant control or remediation.The morphologic and phylogenetic diversity of MTB were first introduced,followed by a critical review of isolation and cultivation methods.Researchers have devoted to optimize the factors,such as oxygen,carbon source,nitrogen source,nutrient broth,iron source,and mineral elements for the growth of MTB.Besides the applications of MTB in modem biological and medical fields,little attention was made on the environmental applications of MTB for wastewater treatment,which has been summarized in this review.For example,applications of MTB as adsorbents have resulted in a novel magnetic separation technology for removal of heavy metals or organic pollutants in wastewater.In addition,we summarized the current advance on pathogen removal and detection of endocrine disruptor which can inspire new insights toward sustainable engineering and practices.Finally,the new perspectives and possible directions for future studies are recommended,such as isolation of MTB.genetic modification of MTB for mass production and new environmental applications.The ultimate objective of this review is to promote the applications of MTB and magnetosomes in the environmental fields.
基金funded by the National Natural Science Foundation of China(Grant No.41872169)the Project of Education Department of Henan Province(No.21A610002)the Innovation and entrepreneurship training plan for college students of Henan Province in 2020(No.S202011517004)。
文摘To develop highly effective adsorbents for chromium removal,a nitrogen-doped biomass-derived carbon(NHPC)was synthesized via direct carbonation of loofah sponge followed by alkali activation and doping modification.NHPC possessed a hierarchical micro-/mesoporous lamellar structure with nitrogen-containing functional groups(1.33 at%),specific surface area(1792.47 m2/g),and pore volume(1.18 cm^(3)/g).NHPC exhibited a higher Cr(Ⅵ)adsorption affinity than the HPC(without nitrogen doping)or the pristine loofah sponge carbon(LSC)did.The influence of process parameters,including pH,dosage,time,temperature,and Cr(Ⅵ)concentration,on Cr(Ⅵ)adsorption by NHPC were evaluated.The Cr(Ⅵ)adsorption kinetics matched with the pseudo-second-order model(R^(2)≥0.9983).The Cr(Ⅵ)adsorption isotherm was fitted with the Langmuir isotherm model,which indicated the maximum Cr(Ⅵ)adsorption capacities:227.27,238.10,and 285.71 mg/g at 298K,308K,and 318K,respectively.The model analysis also indicated that adsorption of Cr(Ⅵ)on NHPC was a spontaneous,endothermal,and entropy-increasing process.The Cr(Ⅵ)adsorption process potentially involved mixed reductive and adsorbed mechanism.Furthermore,computational chemistry calculations revealed that the adsorption energy between NHPC and Cr(VI)(-0.84 eV)was lower than that of HPC(-0.51 eV),suggesting that nitrogen doping could greatly enhance the interaction between NHPC and Cr(VI).
基金the National Natural Science Foundation of China(Grant Nos.51778306,21906001 and 51721006).
文摘The present study evaluated a photo-Fenton reactive membrane that achieved enhanced 1,4-Dioxane removal performance.As a common organic solvent and stabilizer,1,4-Dioxane is widely used in a variety of industrial products and poses negative environmental and health impacts.The membrane was prepared by covalently coating photocatalyst of goethite(α-FeOOH)on a ceramic porous membrane as we reported previously.The effects of UV irradiation,H_(2)O_(2)and catalyst on the removal efficiency of 1,4-Dioxane in batch reactors were first evaluated for optimized reaction conditions,followed by a systematical investigation of 1,4-Dioxane removal in the photo-Fenton membrane filtration mode.Under optimized conditions,the 1,4-Dioxane removal rate reached up to 16%with combination of 2 mmol/L H_(2)O_(2)and UV365 irradiation(2000µW/cm^(2))when the feed water was filtered by the photo-Fenton reactive membrane at a hydraulic retention time of 6 min.The removal efficiency and apparent quantum yield(AQY)were both enhanced in the filtration compared to the batch mode of the same photo-Fenton reaction.Moreover,the proposed degradation pathways were analyzed by density functional theory(DFT)calculations,which provided a new insight into the degradation mechanisms of 1,4-Dioxane in photo-Fenton reactions on the functionalized ceramic membrane.
文摘Shale reservoirs have been a significant focus of hydrocarbon production over the past few decades,and the mechanical assessment of target shale reservoirs has been critical to successful field operations,especially in hydraulic fracturing and well completions.The Unconfined compressive strength(UCS)and Poisson's ratio(ν)are critical mechanical properties in shale reservoir assessment.The estimation and measurement of shale mechanical properties are often erroneous by not accounting for their heterogeneous and pre-existing features,which yield variability of shale mechanical properties along their lithostratigraphy.Thus,there is a need to investigate the degree of correlation and accuracy in multiscale mechanical evaluations of heterogeneous shales,and the correlation between such micromechanical and macromechanical measurements.This study investigated the impact of inherent heterogeneity on the measurement of continuous micromechanical and macromechanical properties of shale reservoirs using scratch test(ST)and uniaxial compression test(UCT)methods,and the degree of correlation(correlation coefficient,r)of measurements in shale was further assessed for the variability of their measured properties.Shale core samples from three distinct shale formations were utilized and studied,and the core samples were subjected to ST and UCT,respectively.The results from this study showed that despite inherent heterogeneous anomalies and natural fractures in the shale samples analyzed,there is a good degree of correlation(UCS:r=0.73;ν:r=0.89)in the micro-and macro-mechanical properties of shales using two independent experimental tests(ST and UCT).This study provides insights for improving the accuracy of mechanical evaluations and numerical modeling in shales with a high degree of heterogeneity and pre-existing natural fractures.The results indicate that when considering the structural complexity and heterogeneity of unconventional reservoirs such as shales,the ST method can provide a better continuous micromechanical assessment of shales.In contrast,the UCT can provide a better bulk macromechanical measurement of shales.
基金This study was supported by the New Jersey Water Resources Research Institute(NJWRRI)Grant(USA)(Project Number:2018NJ399B).
文摘Plastic pollution has been a legacy environment problems and more recently,the plastic particles,especially those ultrafine or small plastics particles,are widely recognized with increasing environmental and ecological impacts.Among small plastics,microplastics are intensively studied,whereas the physicochemical properties,environmental abundance,chemical states,bioavailability and toxicity toward organisms of nanoplastics are inadequately investigated.There are substantial difficulties in separation,visualization and chemical identification of nanoplastics due to their small sizes,relatively low concentrations and interferences from coexisting substances(e.g.,dyes or natural organic matters).Moreover,detection of polymers at nanoscale is largely hampered by the detection limit or sensitivity for existing spectral techniques such as Transformed Infrared Spectroscopy(FTIR)or Raman Spectroscopy.This article critically examined the current state of art techniques that are exclusively reported for nanoplastic characterization in environmental samples.Based on their operation principles,potential applications and limitations of these analytical techniques are carefully analyzed.
文摘Breaker fluids are designed to dissolve filter cakes by breaking their long-chain molecules,thereby removing solid deposits on the wellbore wall.Although breaker fluids are not intended to infiltrate the hydrocarbon reservoir,they can invade and cause formation damage by altering sandstone reservoirs'wettability and relative permeability.This can lead to a reduction in the overall reservoir performance.This study coupled tripartite methods to investigate the potential impact of breaker invasion and transport in hydrocarbon reservoirs and its multiscale effect on the performances of sandstone reservoirs.We utilized experimental,analytical,and numerical methods to assess and predict the susceptibility of reservoirs to breaker fluid invasion and transportation.Our experimental and empirical investigations considered varying breaker fluid formulations to evaluate the effects of breaker fluid concentration,formation temperature,and solution gas-oil ratio(GOR)on residual-oil saturation(ROS)and oil-water relative permeability.By adopting the ROS and relative permeability associated with the 50%v/v breaker fluid mixture,the performance of the hydrocarbon reservoir was numerically simulated under the limiting scenarios of no-invasion,moderate-invasion,and deep-invasion of breaker fluid.The results indicate a positive correlation between breaker fluid concentration and ROS,highlighting the risks that breaker fluid invasion and deep infiltration pose to hydrocarbon recovery.Further,results show that both live-oil condition(LOC)and dead-oil condition(DOC)reservoirs are susceptible to the detrimental impacts of breaker fluid infiltration,while their invasion can reduce hydrocarbon recovery in both LOC(-6%)and DOC(-28%).The multi-scale effects on reservoir performance are more pronounced at near-wellbore and DOC than at far-field and LOC.Findings from this work provide valuable insights into the complexity of breaker-fluid invasion in sandstone reservoirs and the mitigation of associated risks to reservoir performance.
基金supported by National Natural Science Foundation of China(52070122,42007176)Taishan Scholar Foundation,Natural Science Foundation of Shandong Province(ZR2020QD125,ZR2020ME222)+1 种基金Key Scientific and Technological Innovation Foundation of Shandong Province(No.2020CXGC011404)the program of 20 Policies for University in Jinan(202228056).
文摘This study evaluated the physiological characteristics(e.g.,growth parameters,chlorophyll content,metabolites and antioxidative enzymes activity)of Alternanthera philoxeroides(A.philoxeroides),as a hyperaccumulator plant,during the phytoremediation of cadmium(Cd)from water.After cultivating A.philoxeroides in a Cd-containing medium for 30 days,the growth rate was inhibited by up to 33.5%as the exposed Cd concentration increased to 0.80 mmol·L−1.Cd exposure interfered with the photosynthesis of A.philoxeroides and caused oxidative stress as indicated by the rise of malondialdehyde(MDA)and H2O2,which increased by 8 times and 3 times compared to the control group.Moreover,high exposure concentrations of Cd also reduced the activities of multiple antioxidants(e.g.,GSH and AsA),indicating the inhibition of Cd on the plant’s ability to mitigate oxidative damage.Finally,the fluorescent patterns of the rhizosphere dissolved organic matter(rDOM)revealed three major components(humic,fulvic substances and protein-like substances)well correlated with the changes in antioxidant activities.Partial least-squares discriminant analysis(PLS-DA)visualized the difference in the activity of the antioxidative enzymes between different groups.The study unravelled deep insights into the potential mechanisms of tolerance and resistance of A.philoxeroides for phytoremediation of Cd pollution.
