Foam diversion can effectively solve the problem of uneven distribution of acid in layers of different permeabilities during matrix acidizing. Based on gas trapping theory and the mass conservation equation, mathemati...Foam diversion can effectively solve the problem of uneven distribution of acid in layers of different permeabilities during matrix acidizing. Based on gas trapping theory and the mass conservation equation, mathematical models were developed for foam-diverted acidizing, which can be achieved by a foam slug followed by acid injection or by continuous injection of foamed acid. The design method for foam-diverted acidizing was also given. The mathematical models were solved by a computer program. Computed results show that the total formation skin factor, wellhead pressure and bottomhole pressure increase with foam injection, but decrease with acid injection. Volume flow rate in a highpermeability layer decreases, while that in a low-permeability layer increases, thus diverting acid to the low-permeability layer from the high-permeability layer. Under the same formation conditions, for foamed acid treatment the operation was longer, and wellhead and bottomhole pressures are higher. Field application shows that foam slug can effectively block high permeability layers, and improve intake profile noticeably.展开更多
Several derivative disasters such as ground pressure disasters and methane explosions can be caused by the hard roof in coal mines.For limestone roofs with fine integrity and extreme hardness,collapse is difficult and...Several derivative disasters such as ground pressure disasters and methane explosions can be caused by the hard roof in coal mines.For limestone roofs with fine integrity and extreme hardness,collapse is difficult and the effect of conventional roof control methods is limited.Acidizing reformation is an effective way to weaken the strength of roof strata based on acid-rock reaction.In this study,the rock strength damage law and acid reaction characteristics were tested by the limestone acidification experiment.Besides,the strength degradation mechanism of limestone under the acidity effect was analyzed.The results show that the acid corrosion characteristics of limestone are obvious,as numerous mineral grains generate voids under the effects of acid corrosion,and more defects are formed inside.The acid-rock reaction is the most intense at the early stage and then gradually reaches dynamic equilibrium,and the acid corrosion rate of limestone is 4.24%(10%HCl,360 min).The hard limestone is damaged after acidification.Furthermore,the internal cracks can be induced to rapid initiation and unstable propagation under load,which reduces the strain required for rock failure by 33.33%.The failure morphology is more complicated,and the uniaxial compressive strength and elastic modulus decrease by 52.42%and 34.44%respectively.The strength weakening of hard roof after acidification is due to the defects such as intergranular cracking caused by the corrosion of rock crystals under acidity effect,which accelerate the initiation and propagation of internal cracks with external force.Macroscopically,acidification induced the deterioration of rock mechanical properties by reforming the roof structure.The feasibility of acidizing reformation method to control hard roof is confirmed in this study.展开更多
This work mainly studies the effect of fluid phase momentum transfer mechanisms on the acidizing results,including the retardation effect of the porous structure and the interaction between the fluid phase,such as vis...This work mainly studies the effect of fluid phase momentum transfer mechanisms on the acidizing results,including the retardation effect of the porous structure and the interaction between the fluid phase,such as viscous dissipation and inertial effect.The results show that the acid fluid momentum transfer is influenced by the complex porous structure and fluid viscous dissipation.Eventually,the Stokes-Darcy equation is recommended to be adopted to describe the fluid phase momentum transfer in the following numerical simulation studies of the carbonate acidizing process.Based on this model,a parametric research is carried out to investigate the impact of acid on rock physical characteristics in the stimulation process.Increasing the acid concentration appears to minimize the quantity of acid consumed for the breakthrough.The acid surface reaction rate has a considerable impact on the pore volume to breakthrough and the optimum acid injection rate.The influence of permeability on the acidizing results basically shows a negative correlation with the injection rate.The difference between the acidizing curves of different permeability gradually becomes insignificant with the decrease in injection rate.The existence of isolated fracture and vug significantly reduces acid consumption for the breakthrough.展开更多
The Lower Cambrian Longwangmiao dolomite gas reservoirs in the Sichuan Basin are characterized by well-developed natural micro-fractures and dissolved pores and cavities.Due to the strong heterogeneity of reservoirs a...The Lower Cambrian Longwangmiao dolomite gas reservoirs in the Sichuan Basin are characterized by well-developed natural micro-fractures and dissolved pores and cavities.Due to the strong heterogeneity of reservoirs and the serious damage of drilling and completion fluids,acid placement is difficult,and especially the acidizing stimulation of long-interval highly deviated wells or horizontal wells is more difficult.In this paper,the diverting mechanism and rheological behavior of viscoelastic surfactant(VES)based diverting acid was firstly investigated,and the diverting acid with good diversion performance and low secondary damage was selected as the main acid.Then,based on the experimental results of its rheological behaviors,an empirical model of effective viscosity was fitted and a two-scale wormhole propagation model was coupled.And accordingly,a mathematical model for the acidizing of self-diverting acid was established to simulate the pH value,Ca^(2+)concentration,effective viscosity and wormhole shape under the effect of diverting acid in long-interval highly deviated wells that are non-uniformly damaged.Finally,gelled acid and 5%VES diverting acid were compared in terms of their etched wormhole shapes,flow rate dis-tribution and acid imbibition profiles.It is shown that the diverting acid can obviously improve the acid imbibition profile of strong-heterogeneity reservoirs to intensify low-permeability reservoir stimulation.In view of the strong heterogeneity of Longwangmiao dolomite reservoirs and the complexities of drilling and completion fluid damage in the Sichuan Basin,a placement technology was developed for variable VES concentration diverting acid in horizontal wells and long-interval highly deviated wells completed with slotted liners.This acid placement technology has been practically applied in 8 wells and their cumulative gas production rate tested at the wellhead is 1233.46×10^(4)m^(3)/d.The average production stimulation ratio per well is up to 1.95.It provides a support for the efficient development of the Longwangmiao giant gas reservoir.展开更多
The development of shale gas is faced with low reservoir porosity,low reservoir permeability and high formation fracture pressure.In order to deal with these problems,this paper selected shale samples from the bottom ...The development of shale gas is faced with low reservoir porosity,low reservoir permeability and high formation fracture pressure.In order to deal with these problems,this paper selected shale samples from the bottom of the Lower Silurian LongmaxieWufeng Formation of Upper Ordovician in the Weiyuan Block of the southern Sichuan Basin as the research objects.After acid dissolution experiments were carried out,the microstructures and the mechanical parameters of shale after acidizing treatment were investigated by means of X-ray diffraction,scanning electron microscopy and triaxial mechanical test.Then,the effect of acidizing treatment on the microstructures and the mechanical properties of shale were analyzed.And the following research results were obtained.First,after acidizing treatment,the carbonate mineral content of shale decreases and the number and size of pores increase.In the process of dissolution,micro-fractures occur,leading to the increase of shale porosity and permeability.Second,after acidizing treatment,the mechanical properties of shale change.Its deformation mode transforms gradually from elasticebrittle deformation to elasticeplastic deformation,and its fracture mode transits from brittle to semi-brittle and semi-ductile.Third,after shale is treated with the acid with the concentration of 15%for 240 min,its permeability is increased by 3.09 times.After 3 days,its porosity is increased by 1.65 times.And after 7 days,its compressive strength,Young's modulus and brittleness index are decreased by 50.1%,58.1%and 32.8%,respectively.Fourth,the mechanical parameters of shale of the LongmaxieWufeng Formation in the Weiyuan Block is in a quadratic relationship with an average pore size and permeability and in a quadratic or linear relationship with porosity,and their correlation is strong.In conclusion,the research results provide technical support for the prediction of the mechanical parameters of shale in this block after acidizing treatment and for the design of acid fracturing scheme.展开更多
A novel technology (electrokinetics) is proposed to improve acidizing operations, i.e., increase the penetration distance. The acid dissolves the carbonates (limestones/dolomites), enlarging the pores and increasing t...A novel technology (electrokinetics) is proposed to improve acidizing operations, i.e., increase the penetration distance. The acid dissolves the carbonates (limestones/dolomites), enlarging the pores and increasing the width of pre-existing fractures. This gives rise to an increase in permeability. The principal acid commonly used is hydrochloric (HCl), which is pumped through tubing. Aqueous solutions of hydrochloric acid (usually 15%) are pumped into the carbonate formations to enlarge the pores and pre-existing fractures. Without application of D.C. current, the penetration distance is usually very short, especially in tight rocks. However, the penetration distance of acid is very short. By applying D.C. current, one can drive the acid for long distances into the formation being acidized.展开更多
When the conventional sandstone acidizing technologies are adopted,many slugs are needed in the injection of prepad fluid,treatment fluid and postpad fluid,and consequently the production and operation suffers inconve...When the conventional sandstone acidizing technologies are adopted,many slugs are needed in the injection of prepad fluid,treatment fluid and postpad fluid,and consequently the production and operation suffers inconveniences and difficulties.In view of this,a kind of HA integrated acid system which is mainly composed of organic polybasic acids(HA)+HCl+HF and an efficient organic solvent was developed in this paper based on the idea of integrated acid replacing"multiple steps"and high efficiency and intensification.Via this HA integrated acid system,the complicated blockage in sandstone reservoirs can be removed effectively.Then,experiments were carried out on this system to evaluate its performance in terms of its retardance,organic blockage dissolution,chelating and precipitation inhibition.It is indicated that this new system can not only realize the acidizing of conventional integrated acid,but also present a good retarding performance by controlling Ht multi-stage ionization step by step and by forming silica acid-aluminum phosphonate film on the surface of clay minerals;that via this new HA integrated acid system,the organic blockage can be removed efficiently;and that it is wider in pH solution range than conventional APCs(aminopolycarboxyliates)chelants,stronger in chelating capacity of Ca^(2+),Mg^(2+)and Fe^(3+)than conventional chelants(e.g.EDTA,NTA and DTPA),and better in precipitation inhibition on metal fluoride,fluosilicic acid alkali metal,fluoaluminic acid alkali metal and hydroxide than multihydrogen acid,fluoboric acid and mud acid systems.These research results provide a technical support for the plugging removal in hightemperature deep oil and gas reservoirs.展开更多
Conventional diverting techniques may not be useful,and the use of the advanced and well-documented diverting technique is needed to overcome the complexity and heterogeneity of carbonate reservoirs.Nowadays,there hav...Conventional diverting techniques may not be useful,and the use of the advanced and well-documented diverting technique is needed to overcome the complexity and heterogeneity of carbonate reservoirs.Nowadays,there have been a lot of materials and techniques utilized for acid diversion.This paper aimed to consider various utilization of fiber-assisted self as the diverting system in acidifying carbonate reservoirs.One of the main reasons for its ability to overcome uncertainty is that the fiber itself is an inherent property,allowing for an automatic diversion adjustment downhole.When a media with infinite permeability,such as a perforation tunnel or natural fracture,is filled and bridged with a material of finite permeability such as degradable fiber,this creates a temporary skin to injectivity in that zone.This is a powerful concept,as it is a way,despite uncertainty from a lack of logging data or uncertainty in the data itself,of dampening the reservoir’s natural permeability contrast.It does not rely on petrophysical certainty to design a successful treatment.展开更多
Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’...Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’s disease.In this review,we summarize the changes in short-chain fatty acid levels and the abundance of short-chain fatty acid-producing bacteria in various samples from patients with Parkinson’s disease,highlighting the critical role of gut homeostasis imbalance in the pathogenesis and progression of the disease.Focusing on the nervous system,we discuss the molecular mechanisms by which short-chain fatty acids influence the homeostasis of both the enteric nervous system and the central nervous system.We identify key processes,including the activation of G protein-coupled receptors and the inhibition of histone deacetylases by short-chain fatty acids.Importantly,structural or functional disruptions in the enteric nervous system mediated by these fatty acids may lead to abnormalα-synuclein expression and gastrointestinal dysmotility,which could serve as an initiating event in Parkinson’s disease.Furthermore,we propose that short-chain fatty acids help establish communication between the enteric nervous system and the central nervous system via the vagal nerve,immune circulation,and endocrine signaling.This communication may shed light on their potential role in the transmission ofα-synuclein from the gut to the brain.Finally,we elucidate novel treatment strategies for Parkinson’s disease that target short-chain fatty acids and examine the challenges associated with translating short-chain fatty acid-based therapies into clinical practice.In conclusion,this review emphasizes the pivotal role of short-chain fatty acids in regulating gut-brain axis integrity and their significance in the pathogenesis of Parkinson’s disease from the perspective of the nervous system.Moreover,it highlights the potential value of short-chain fatty acids in early intervention for Parkinson’s disease.Future research into the molecular mechanisms of short-chain fatty acids and their synergistic interactions with other gut metabolites is likely to advance the clinical translation of innovative short-chain fatty acid-based therapies for Parkinson’s disease.展开更多
BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probi...BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probiotics have shown good potential in regulating the endocrine system and improving the intestinal microecology,providing new ideas for the treatment of breast hyperplasia.OBJECTIVE:To explore the effects and mechanisms of traditional Chinese medicine compounds and fermented probiotic compounds on breast hyperplasia in mice,providing new theoretical and experimental bases for the clinical treatment and prevention of breast hyperplasia.METHODS:(1)Network pharmacology tools were used to predict the anti-breast-hyperplasia activity of Herba Gueldenstaedtiae(Euphorbia humifusa),as well as its potential targets and signaling pathways.The databases included:TCMSP,OMIM,GeneCards database,UniProt website,Venny2.1.0 website,Metascape,HERB website,and STRING database,all of which are open-access databases.Network pharmacology can predict and screen key information such as the targets corresponding to the active ingredients of traditional Chinese medicine,disease targets,and action pathways through network analysis and computer-system analysis.Therefore,it has been increasingly widely used in the research of traditional Chinese medicine.(2)A breast hyperplasia model was induced in mice by injecting estrogen and progesterone.Mice in the normal blank group were injected intraperitoneally with normal saline every day.Mice in the model group and drugadministration groups were injected intraperitoneally with estradiol benzoate injection at a concentration of 0.5 mg/kg every day for 25 days.From the 26th day,the injection of estradiol benzoate injection was stopped.Mice in the normal blank group were injected intramuscularly with normal saline every day,and mice in the model group and drug-administration groups were injected intramuscularly with progesterone injection at a concentration of 5 mg/kg for 5 days.After the model was established,each group was given drugs respectively.The normal blank group and the model group were gavaged with 0.2 mL/d of normal saline;the positive blank group(Xiaozheng Pill group)was gavaged with an aqueous solution of Xiaozheng Pill at 0.9 mg/g;the low-,medium-and high-dose groups of Compound Herba Gueldenstaedtiae were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively;the low-,medium-and high-dose groups of traditional Chinese medicine-bacteria fermentation were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively.The administration was continuous for 30 days.RESULTS AND CONCLUSION:(1)The results of network pharmacology research showed that the Compound Herba Gueldenstaedtiae(Euphorbia humifusa)contained 46 active ingredients,which were related to 1213 potential targets.After comparison with 588 known breast-hyperplasia targets,it was speculated that 50 of these targets might be related to the direct effect of the compound on breast hyperplasia.(2)After drug intervention,there was no significant change in the high-dose group of Compound Herba Gueldenstaedtiae compared with the normal blank group.The liver indicators of the other intervention groups all significantly decreased(P<0.05).(3)In terms of kidney and uterine indicators,the medium-dose group of Compound Herba Gueldenstaedtiae decreased significantly compared with the normal blank group(P<0.05).In terms of the uterine index,the model group increased significantly compared with the normal blank group(P<0.01).(4)After 1-month drug treatment,the number of lobules and acini in the breast tissue of the Xiaozheng Pill group,the low,medium,and high-dose group of Compound Herba Gueldenstaedtiae,the low,medium,and highdose groups of traditional Chinese medicine-bacteria fermentation decreased,and the duct openings narrowed.With the increase of drug dose,diffuse hyperplasia of breast tissue was significantly improved.(5)The ELISA results showed that compared with the model group,the estrogen level was lower in the medium-dose group of traditional Chinese medicine-bacteria fermentation after the intervention(P<0.05).In addition,the follicle-stimulating hormone level in the low-dose group of Compound Herba Gueldenstaedtiae was lower than that of the model group(P<0.05).(6)The intervention in the mouse model led to changes in the abundance of short chain fatty acids and intestinal flora in all groups.To conclude,the Compound Herba Gueldenstaedtiae and its probiotic fermentation products significantly improved mammary gland hyperplasia in mice by regulating hormone levels,improving the structure of the gut microbiota,and increasing the content of shortchain fatty acids,providing new ideas and potential sources of drugs for the treatment of breast hyperplasia.展开更多
Foam diversion acidizing can effectively solve the problem of acid distribution with severe heterogeneity between and within layers.Based on the foam diversion principle,the gas trap theory,and volume conservation pri...Foam diversion acidizing can effectively solve the problem of acid distribution with severe heterogeneity between and within layers.Based on the foam diversion principle,the gas trap theory,and volume conservation principle,the foam slug diversion acidizing model was established and solved considering the change of bottomhole temperature and deviation factor of foam.The simulation results show that the change of temperature has a great influence on the diversion effect at the initial stage of injection,but a small influence at the middle and late stage.The effect of temperature on the highly permeable layer is greater than that of temperature on the low permeability layer.The deviation factor of foam is mainly controlled by temperature at the initial stage,and by pressure at the middle and late stage,and the whole process shows a downward trend,which has little influence on the diversion effect.The quasi-skin factor of gas trap is the most important parameter that influences the effect of foam diversion.The water saturation of the low permeability layer rises faster than that of the high permeability layer,and the effect of diversion is obvious.The research results have a strong guiding significance for foam diversion acidizing.展开更多
For many years,the most common acid practice for sandstone acidizing is based on mud acid and dolomite formations using hydrochloric acid.During various stages of sandstone acidizing,different acids react with differe...For many years,the most common acid practice for sandstone acidizing is based on mud acid and dolomite formations using hydrochloric acid.During various stages of sandstone acidizing,different acids react with different minerals,and interactions of minerals with acids are an origin for precipitation reactions,which can be possibly deleterious as they may reduce reservoir permeability.During this research,the effects of chelates on pore size distribution,mineralogy,and grain size distribution have been investigated.Various chelates(GLDA,HEDTA,EDTA)were examined to react with different Berea Sandstone samples at a temperature of 180F and under 1000 psi confining pressure.Experimental techniques and analysis like Tescan Integrated Mineral Analysis(TIMA),were implemented in this research to understand the effect of chelates on Berea Sandstone.These results are related to elemental mass,element deportment,mineral mass,mineral locking,grain size distribution,and particle size distribution of the core samples reacted with different chelating agents.It has been found that all the chelating agents are effective in increasing the porosity and dissolving the cations from the Berea sandstone core sample.HEDTA proved to be more effective in dissolving quartz as compared to other chelates.GLDA proved to be more effective in the dissolution of rutile and zircon minerals.The significance of this research is the application of environment-friendly chelating agents to sandstone formation.Moreover,the detailed mineral analysis revealed that the most number of particles were dissolved by HEDTA.展开更多
Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,includi...Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,including cerebrospinal fluid,varies significantly(Figure 1Α;Yung et al.,2014).LPA actually corresponds to a variety of lipid species that include different stereoisomers with either saturated or unsaturated fatty acids bearing likely differentiated biological activities(Figure 1Α;Yung et al.,2014;Hernández-Araiza et al.,2018).展开更多
Acidizing treatment is considered as a significant process in the oil well stimulations to form wormholes in carbonate formation in order to enhance the reservoir fluid production.Obtaining the number of pore volumes ...Acidizing treatment is considered as a significant process in the oil well stimulations to form wormholes in carbonate formation in order to enhance the reservoir fluid production.Obtaining the number of pore volumes to breakthrough is an important objective in matrix acidizing,for it contributes to determining the wormhole characteristics such as type,shape,and size.Finding this number in experimental works requires a considerable amount of time,energy and cost.Therefore,this study aimed to establish an analytical method in which a reasonable result is achieved for the number of pore volumes to breakthrough.This purpose is accomplished by solely implementing acid and formation properties without performing any experimental works.The process of wormhole creation is done through developing a numerical model by utilizing the conservation of mass law method in which the carbonate core is considered as a closed system and the overall mass in the system as constant during the acid injection process.Furthermore,a constant number is added to the mathematical part of the model in order to eliminate the dimensionless Damk鰄ler number which is supposed to be calculated experimentally.The results of the numerical procedure of the model are further compared to four other experimental works,which led to calculating the average accuracy of this model that is shown to be 95.98%.This study puts forward a comprehensive numerical model to estimate the number of pore volumes to breakthrough with an acceptable accuracy rate merely through implementing known acid and core properties.展开更多
The global prevalence of metabolic-associated fatty liver disease(MAFLD)is on the rise,seriously threatening human health.Currently,no specific approved drugs are available for its treatment.This paper reviews the pat...The global prevalence of metabolic-associated fatty liver disease(MAFLD)is on the rise,seriously threatening human health.Currently,no specific approved drugs are available for its treatment.This paper reviews the pathogenesis of MAFLD,covering aspects like lipid accumulation and insulin resistance,oxidative stress,endoplasmic reticulum stress(ERS),lipotoxicity-induced hepatocyte damage,and fibrosis.It also elaborates on multiple treatment approaches for MAFLD,including metabolic regulation,improvement of the gut-liver axis interaction,modulation of immune and inflammatory pathways,enhancement of the adipose tissue-liver interaction,alleviation of fibrosis,prevention of hepatocyte injury,and traditional Chinese medicine(TCM)external therapies.Additionally,natural product research advancements,individual Chinese medicine components,and mixed herbal formulas for MAFLD treatment is provided.Many natural products and traditional Chinese medicines exhibit favorable effects in regulating lipid metabolism,anti-inflammation,and anti-oxidation,offering new directions and potential drug options for MAFLD treatment.This is expected to provide a reference for future clinical treatment and drug development.展开更多
Microglia are the resident macrophages of the central nervous system.They act as the first line of defense against pathogens and play essential roles in neuroinflammation and tissue repair after brain insult or in neu...Microglia are the resident macrophages of the central nervous system.They act as the first line of defense against pathogens and play essential roles in neuroinflammation and tissue repair after brain insult or in neurodegenerative and demyelinating diseases(Borst et al.,2021).Together with infiltrating monocyte-derived macrophages,microglia also play a critical role for brain tumor development,since immunosuppressive interactions between tumor cells and tumor-associated microglia and macrophages(TAM)are linked to malignant progression.This mechanism is of particular relevance in glioblastoma(GB),the deadliest form of brain cancer with a median overall survival of less than 15 months(Khan et al.,2023).Therefore,targeting microglia and macrophage activation is a promising strategy for therapeutic interference in brain disease.展开更多
Obesity is widely recognized as a global epidemic,primarily driven by an imbalance between energy expenditure and caloric intake associated with a sedentary lifestyle.Diets high in carbohydrates and saturated fats,par...Obesity is widely recognized as a global epidemic,primarily driven by an imbalance between energy expenditure and caloric intake associated with a sedentary lifestyle.Diets high in carbohydrates and saturated fats,particularly palmitic acid,are potent inducers of chronic low-grade inflammation,largely due to disruptions in glucose metabolism and the onset of insulin resistance(Qiu et al.,2022).While many organs are affected,the brain,specifically the hypothalamus,is among the first to exhibit inflammation in response to an unhealthy diet,suggesting that obesity may,in fact,be a brain-centered disease with neuroinflammation as a central factor(Thaler et al., 2012).展开更多
文摘Foam diversion can effectively solve the problem of uneven distribution of acid in layers of different permeabilities during matrix acidizing. Based on gas trapping theory and the mass conservation equation, mathematical models were developed for foam-diverted acidizing, which can be achieved by a foam slug followed by acid injection or by continuous injection of foamed acid. The design method for foam-diverted acidizing was also given. The mathematical models were solved by a computer program. Computed results show that the total formation skin factor, wellhead pressure and bottomhole pressure increase with foam injection, but decrease with acid injection. Volume flow rate in a highpermeability layer decreases, while that in a low-permeability layer increases, thus diverting acid to the low-permeability layer from the high-permeability layer. Under the same formation conditions, for foamed acid treatment the operation was longer, and wellhead and bottomhole pressures are higher. Field application shows that foam slug can effectively block high permeability layers, and improve intake profile noticeably.
基金This work was supported by the National Natural Science Foundation of China(No.51774272)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX21_2337).
文摘Several derivative disasters such as ground pressure disasters and methane explosions can be caused by the hard roof in coal mines.For limestone roofs with fine integrity and extreme hardness,collapse is difficult and the effect of conventional roof control methods is limited.Acidizing reformation is an effective way to weaken the strength of roof strata based on acid-rock reaction.In this study,the rock strength damage law and acid reaction characteristics were tested by the limestone acidification experiment.Besides,the strength degradation mechanism of limestone under the acidity effect was analyzed.The results show that the acid corrosion characteristics of limestone are obvious,as numerous mineral grains generate voids under the effects of acid corrosion,and more defects are formed inside.The acid-rock reaction is the most intense at the early stage and then gradually reaches dynamic equilibrium,and the acid corrosion rate of limestone is 4.24%(10%HCl,360 min).The hard limestone is damaged after acidification.Furthermore,the internal cracks can be induced to rapid initiation and unstable propagation under load,which reduces the strain required for rock failure by 33.33%.The failure morphology is more complicated,and the uniaxial compressive strength and elastic modulus decrease by 52.42%and 34.44%respectively.The strength weakening of hard roof after acidification is due to the defects such as intergranular cracking caused by the corrosion of rock crystals under acidity effect,which accelerate the initiation and propagation of internal cracks with external force.Macroscopically,acidification induced the deterioration of rock mechanical properties by reforming the roof structure.The feasibility of acidizing reformation method to control hard roof is confirmed in this study.
基金financial support from the Key Project of the National Natural Science Foundation of China(No.52034010)the China Scholarship Council(201906450038)
文摘This work mainly studies the effect of fluid phase momentum transfer mechanisms on the acidizing results,including the retardation effect of the porous structure and the interaction between the fluid phase,such as viscous dissipation and inertial effect.The results show that the acid fluid momentum transfer is influenced by the complex porous structure and fluid viscous dissipation.Eventually,the Stokes-Darcy equation is recommended to be adopted to describe the fluid phase momentum transfer in the following numerical simulation studies of the carbonate acidizing process.Based on this model,a parametric research is carried out to investigate the impact of acid on rock physical characteristics in the stimulation process.Increasing the acid concentration appears to minimize the quantity of acid consumed for the breakthrough.The acid surface reaction rate has a considerable impact on the pore volume to breakthrough and the optimum acid injection rate.The influence of permeability on the acidizing results basically shows a negative correlation with the injection rate.The difference between the acidizing curves of different permeability gradually becomes insignificant with the decrease in injection rate.The existence of isolated fracture and vug significantly reduces acid consumption for the breakthrough.
基金Project supported by the National Science and Technology Major Project“Large-scale Oil and Gas Fields and CBM Development:Demonstration Project of Large-scale Carbonate Gas Fields in Sichuan Basin”(Code:2016ZX05052)CNPC Major Science and Technology Project“Research and Application of Deep-Temperature and High-Pressure Sulfur Gas Reservoir Reformation Technology in Sichuan Basin”(Code:2016E-0609).
文摘The Lower Cambrian Longwangmiao dolomite gas reservoirs in the Sichuan Basin are characterized by well-developed natural micro-fractures and dissolved pores and cavities.Due to the strong heterogeneity of reservoirs and the serious damage of drilling and completion fluids,acid placement is difficult,and especially the acidizing stimulation of long-interval highly deviated wells or horizontal wells is more difficult.In this paper,the diverting mechanism and rheological behavior of viscoelastic surfactant(VES)based diverting acid was firstly investigated,and the diverting acid with good diversion performance and low secondary damage was selected as the main acid.Then,based on the experimental results of its rheological behaviors,an empirical model of effective viscosity was fitted and a two-scale wormhole propagation model was coupled.And accordingly,a mathematical model for the acidizing of self-diverting acid was established to simulate the pH value,Ca^(2+)concentration,effective viscosity and wormhole shape under the effect of diverting acid in long-interval highly deviated wells that are non-uniformly damaged.Finally,gelled acid and 5%VES diverting acid were compared in terms of their etched wormhole shapes,flow rate dis-tribution and acid imbibition profiles.It is shown that the diverting acid can obviously improve the acid imbibition profile of strong-heterogeneity reservoirs to intensify low-permeability reservoir stimulation.In view of the strong heterogeneity of Longwangmiao dolomite reservoirs and the complexities of drilling and completion fluid damage in the Sichuan Basin,a placement technology was developed for variable VES concentration diverting acid in horizontal wells and long-interval highly deviated wells completed with slotted liners.This acid placement technology has been practically applied in 8 wells and their cumulative gas production rate tested at the wellhead is 1233.46×10^(4)m^(3)/d.The average production stimulation ratio per well is up to 1.95.It provides a support for the efficient development of the Longwangmiao giant gas reservoir.
基金supported by the National Natural Science Foundation of China"Flow mechanism of induced fractures and conductivity prediction model of shale fracture network in deep strata under high pressure"(No.:51704251)"Fracturing and acidizing of low-permeability and tight reservoirs"(No.:51525404).
文摘The development of shale gas is faced with low reservoir porosity,low reservoir permeability and high formation fracture pressure.In order to deal with these problems,this paper selected shale samples from the bottom of the Lower Silurian LongmaxieWufeng Formation of Upper Ordovician in the Weiyuan Block of the southern Sichuan Basin as the research objects.After acid dissolution experiments were carried out,the microstructures and the mechanical parameters of shale after acidizing treatment were investigated by means of X-ray diffraction,scanning electron microscopy and triaxial mechanical test.Then,the effect of acidizing treatment on the microstructures and the mechanical properties of shale were analyzed.And the following research results were obtained.First,after acidizing treatment,the carbonate mineral content of shale decreases and the number and size of pores increase.In the process of dissolution,micro-fractures occur,leading to the increase of shale porosity and permeability.Second,after acidizing treatment,the mechanical properties of shale change.Its deformation mode transforms gradually from elasticebrittle deformation to elasticeplastic deformation,and its fracture mode transits from brittle to semi-brittle and semi-ductile.Third,after shale is treated with the acid with the concentration of 15%for 240 min,its permeability is increased by 3.09 times.After 3 days,its porosity is increased by 1.65 times.And after 7 days,its compressive strength,Young's modulus and brittleness index are decreased by 50.1%,58.1%and 32.8%,respectively.Fourth,the mechanical parameters of shale of the LongmaxieWufeng Formation in the Weiyuan Block is in a quadratic relationship with an average pore size and permeability and in a quadratic or linear relationship with porosity,and their correlation is strong.In conclusion,the research results provide technical support for the prediction of the mechanical parameters of shale in this block after acidizing treatment and for the design of acid fracturing scheme.
文摘A novel technology (electrokinetics) is proposed to improve acidizing operations, i.e., increase the penetration distance. The acid dissolves the carbonates (limestones/dolomites), enlarging the pores and increasing the width of pre-existing fractures. This gives rise to an increase in permeability. The principal acid commonly used is hydrochloric (HCl), which is pumped through tubing. Aqueous solutions of hydrochloric acid (usually 15%) are pumped into the carbonate formations to enlarge the pores and pre-existing fractures. Without application of D.C. current, the penetration distance is usually very short, especially in tight rocks. However, the penetration distance of acid is very short. By applying D.C. current, one can drive the acid for long distances into the formation being acidized.
基金Project supported by National Science and Technology Major Project“Development of Large Oil and Gas Fields and Coalbed Methane”(No.2016ZX05058-003).
文摘When the conventional sandstone acidizing technologies are adopted,many slugs are needed in the injection of prepad fluid,treatment fluid and postpad fluid,and consequently the production and operation suffers inconveniences and difficulties.In view of this,a kind of HA integrated acid system which is mainly composed of organic polybasic acids(HA)+HCl+HF and an efficient organic solvent was developed in this paper based on the idea of integrated acid replacing"multiple steps"and high efficiency and intensification.Via this HA integrated acid system,the complicated blockage in sandstone reservoirs can be removed effectively.Then,experiments were carried out on this system to evaluate its performance in terms of its retardance,organic blockage dissolution,chelating and precipitation inhibition.It is indicated that this new system can not only realize the acidizing of conventional integrated acid,but also present a good retarding performance by controlling Ht multi-stage ionization step by step and by forming silica acid-aluminum phosphonate film on the surface of clay minerals;that via this new HA integrated acid system,the organic blockage can be removed efficiently;and that it is wider in pH solution range than conventional APCs(aminopolycarboxyliates)chelants,stronger in chelating capacity of Ca^(2+),Mg^(2+)and Fe^(3+)than conventional chelants(e.g.EDTA,NTA and DTPA),and better in precipitation inhibition on metal fluoride,fluosilicic acid alkali metal,fluoaluminic acid alkali metal and hydroxide than multihydrogen acid,fluoboric acid and mud acid systems.These research results provide a technical support for the plugging removal in hightemperature deep oil and gas reservoirs.
文摘Conventional diverting techniques may not be useful,and the use of the advanced and well-documented diverting technique is needed to overcome the complexity and heterogeneity of carbonate reservoirs.Nowadays,there have been a lot of materials and techniques utilized for acid diversion.This paper aimed to consider various utilization of fiber-assisted self as the diverting system in acidifying carbonate reservoirs.One of the main reasons for its ability to overcome uncertainty is that the fiber itself is an inherent property,allowing for an automatic diversion adjustment downhole.When a media with infinite permeability,such as a perforation tunnel or natural fracture,is filled and bridged with a material of finite permeability such as degradable fiber,this creates a temporary skin to injectivity in that zone.This is a powerful concept,as it is a way,despite uncertainty from a lack of logging data or uncertainty in the data itself,of dampening the reservoir’s natural permeability contrast.It does not rely on petrophysical certainty to design a successful treatment.
基金supported by the National Key R&D Program of China,No.2021YFC2501200(to PC).
文摘Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’s disease.In this review,we summarize the changes in short-chain fatty acid levels and the abundance of short-chain fatty acid-producing bacteria in various samples from patients with Parkinson’s disease,highlighting the critical role of gut homeostasis imbalance in the pathogenesis and progression of the disease.Focusing on the nervous system,we discuss the molecular mechanisms by which short-chain fatty acids influence the homeostasis of both the enteric nervous system and the central nervous system.We identify key processes,including the activation of G protein-coupled receptors and the inhibition of histone deacetylases by short-chain fatty acids.Importantly,structural or functional disruptions in the enteric nervous system mediated by these fatty acids may lead to abnormalα-synuclein expression and gastrointestinal dysmotility,which could serve as an initiating event in Parkinson’s disease.Furthermore,we propose that short-chain fatty acids help establish communication between the enteric nervous system and the central nervous system via the vagal nerve,immune circulation,and endocrine signaling.This communication may shed light on their potential role in the transmission ofα-synuclein from the gut to the brain.Finally,we elucidate novel treatment strategies for Parkinson’s disease that target short-chain fatty acids and examine the challenges associated with translating short-chain fatty acid-based therapies into clinical practice.In conclusion,this review emphasizes the pivotal role of short-chain fatty acids in regulating gut-brain axis integrity and their significance in the pathogenesis of Parkinson’s disease from the perspective of the nervous system.Moreover,it highlights the potential value of short-chain fatty acids in early intervention for Parkinson’s disease.Future research into the molecular mechanisms of short-chain fatty acids and their synergistic interactions with other gut metabolites is likely to advance the clinical translation of innovative short-chain fatty acid-based therapies for Parkinson’s disease.
文摘BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probiotics have shown good potential in regulating the endocrine system and improving the intestinal microecology,providing new ideas for the treatment of breast hyperplasia.OBJECTIVE:To explore the effects and mechanisms of traditional Chinese medicine compounds and fermented probiotic compounds on breast hyperplasia in mice,providing new theoretical and experimental bases for the clinical treatment and prevention of breast hyperplasia.METHODS:(1)Network pharmacology tools were used to predict the anti-breast-hyperplasia activity of Herba Gueldenstaedtiae(Euphorbia humifusa),as well as its potential targets and signaling pathways.The databases included:TCMSP,OMIM,GeneCards database,UniProt website,Venny2.1.0 website,Metascape,HERB website,and STRING database,all of which are open-access databases.Network pharmacology can predict and screen key information such as the targets corresponding to the active ingredients of traditional Chinese medicine,disease targets,and action pathways through network analysis and computer-system analysis.Therefore,it has been increasingly widely used in the research of traditional Chinese medicine.(2)A breast hyperplasia model was induced in mice by injecting estrogen and progesterone.Mice in the normal blank group were injected intraperitoneally with normal saline every day.Mice in the model group and drugadministration groups were injected intraperitoneally with estradiol benzoate injection at a concentration of 0.5 mg/kg every day for 25 days.From the 26th day,the injection of estradiol benzoate injection was stopped.Mice in the normal blank group were injected intramuscularly with normal saline every day,and mice in the model group and drug-administration groups were injected intramuscularly with progesterone injection at a concentration of 5 mg/kg for 5 days.After the model was established,each group was given drugs respectively.The normal blank group and the model group were gavaged with 0.2 mL/d of normal saline;the positive blank group(Xiaozheng Pill group)was gavaged with an aqueous solution of Xiaozheng Pill at 0.9 mg/g;the low-,medium-and high-dose groups of Compound Herba Gueldenstaedtiae were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively;the low-,medium-and high-dose groups of traditional Chinese medicine-bacteria fermentation were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively.The administration was continuous for 30 days.RESULTS AND CONCLUSION:(1)The results of network pharmacology research showed that the Compound Herba Gueldenstaedtiae(Euphorbia humifusa)contained 46 active ingredients,which were related to 1213 potential targets.After comparison with 588 known breast-hyperplasia targets,it was speculated that 50 of these targets might be related to the direct effect of the compound on breast hyperplasia.(2)After drug intervention,there was no significant change in the high-dose group of Compound Herba Gueldenstaedtiae compared with the normal blank group.The liver indicators of the other intervention groups all significantly decreased(P<0.05).(3)In terms of kidney and uterine indicators,the medium-dose group of Compound Herba Gueldenstaedtiae decreased significantly compared with the normal blank group(P<0.05).In terms of the uterine index,the model group increased significantly compared with the normal blank group(P<0.01).(4)After 1-month drug treatment,the number of lobules and acini in the breast tissue of the Xiaozheng Pill group,the low,medium,and high-dose group of Compound Herba Gueldenstaedtiae,the low,medium,and highdose groups of traditional Chinese medicine-bacteria fermentation decreased,and the duct openings narrowed.With the increase of drug dose,diffuse hyperplasia of breast tissue was significantly improved.(5)The ELISA results showed that compared with the model group,the estrogen level was lower in the medium-dose group of traditional Chinese medicine-bacteria fermentation after the intervention(P<0.05).In addition,the follicle-stimulating hormone level in the low-dose group of Compound Herba Gueldenstaedtiae was lower than that of the model group(P<0.05).(6)The intervention in the mouse model led to changes in the abundance of short chain fatty acids and intestinal flora in all groups.To conclude,the Compound Herba Gueldenstaedtiae and its probiotic fermentation products significantly improved mammary gland hyperplasia in mice by regulating hormone levels,improving the structure of the gut microbiota,and increasing the content of shortchain fatty acids,providing new ideas and potential sources of drugs for the treatment of breast hyperplasia.
基金The work in this paper is supported by the grant from the Na-tional Natural Science Foundation of China(No.U1762107)Science and technology program of Sichuan Province(No.2019YJ0425).
文摘Foam diversion acidizing can effectively solve the problem of acid distribution with severe heterogeneity between and within layers.Based on the foam diversion principle,the gas trap theory,and volume conservation principle,the foam slug diversion acidizing model was established and solved considering the change of bottomhole temperature and deviation factor of foam.The simulation results show that the change of temperature has a great influence on the diversion effect at the initial stage of injection,but a small influence at the middle and late stage.The effect of temperature on the highly permeable layer is greater than that of temperature on the low permeability layer.The deviation factor of foam is mainly controlled by temperature at the initial stage,and by pressure at the middle and late stage,and the whole process shows a downward trend,which has little influence on the diversion effect.The quasi-skin factor of gas trap is the most important parameter that influences the effect of foam diversion.The water saturation of the low permeability layer rises faster than that of the high permeability layer,and the effect of diversion is obvious.The research results have a strong guiding significance for foam diversion acidizing.
文摘For many years,the most common acid practice for sandstone acidizing is based on mud acid and dolomite formations using hydrochloric acid.During various stages of sandstone acidizing,different acids react with different minerals,and interactions of minerals with acids are an origin for precipitation reactions,which can be possibly deleterious as they may reduce reservoir permeability.During this research,the effects of chelates on pore size distribution,mineralogy,and grain size distribution have been investigated.Various chelates(GLDA,HEDTA,EDTA)were examined to react with different Berea Sandstone samples at a temperature of 180F and under 1000 psi confining pressure.Experimental techniques and analysis like Tescan Integrated Mineral Analysis(TIMA),were implemented in this research to understand the effect of chelates on Berea Sandstone.These results are related to elemental mass,element deportment,mineral mass,mineral locking,grain size distribution,and particle size distribution of the core samples reacted with different chelating agents.It has been found that all the chelating agents are effective in increasing the porosity and dissolving the cations from the Berea sandstone core sample.HEDTA proved to be more effective in dissolving quartz as compared to other chelates.GLDA proved to be more effective in the dissolution of rutile and zircon minerals.The significance of this research is the application of environment-friendly chelating agents to sandstone formation.Moreover,the detailed mineral analysis revealed that the most number of particles were dissolved by HEDTA.
基金supported by the Hellenic Foundation for Research and Innovation,HFRI,“2nd Call for HFRI Research Projects to support Faculty Members&Researchers”Project 02667 to GL.
文摘Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,including cerebrospinal fluid,varies significantly(Figure 1Α;Yung et al.,2014).LPA actually corresponds to a variety of lipid species that include different stereoisomers with either saturated or unsaturated fatty acids bearing likely differentiated biological activities(Figure 1Α;Yung et al.,2014;Hernández-Araiza et al.,2018).
文摘Acidizing treatment is considered as a significant process in the oil well stimulations to form wormholes in carbonate formation in order to enhance the reservoir fluid production.Obtaining the number of pore volumes to breakthrough is an important objective in matrix acidizing,for it contributes to determining the wormhole characteristics such as type,shape,and size.Finding this number in experimental works requires a considerable amount of time,energy and cost.Therefore,this study aimed to establish an analytical method in which a reasonable result is achieved for the number of pore volumes to breakthrough.This purpose is accomplished by solely implementing acid and formation properties without performing any experimental works.The process of wormhole creation is done through developing a numerical model by utilizing the conservation of mass law method in which the carbonate core is considered as a closed system and the overall mass in the system as constant during the acid injection process.Furthermore,a constant number is added to the mathematical part of the model in order to eliminate the dimensionless Damk鰄ler number which is supposed to be calculated experimentally.The results of the numerical procedure of the model are further compared to four other experimental works,which led to calculating the average accuracy of this model that is shown to be 95.98%.This study puts forward a comprehensive numerical model to estimate the number of pore volumes to breakthrough with an acceptable accuracy rate merely through implementing known acid and core properties.
基金supported by the National Natural Science Foundation of China(82574477)the Jiangsu Provincial Traditional Chinese Medicine Science and Technology Development Plan(QN202426)+5 种基金Jiangsu Province“333 High-level Talents Training Project”((2024)3-0189)Youth Talent Support Project of the Jiangsu Association for Science and Technology(TJ-2023-053)Shanxi Provincial Department-Municipal Key Laboratory Cultivation Base for Quality Enhancement and Utilization of Shangdang Chinese Medicinal Materials(KF202401)Fundamental Research Program of Shanxi Province(202403021221211)the research project supported by the Shanxi Scholarship Council of China(No.2023-158)Open Project of Key Laboratory of Tibetan Medicine Basic Research,Ministry of Education.
文摘The global prevalence of metabolic-associated fatty liver disease(MAFLD)is on the rise,seriously threatening human health.Currently,no specific approved drugs are available for its treatment.This paper reviews the pathogenesis of MAFLD,covering aspects like lipid accumulation and insulin resistance,oxidative stress,endoplasmic reticulum stress(ERS),lipotoxicity-induced hepatocyte damage,and fibrosis.It also elaborates on multiple treatment approaches for MAFLD,including metabolic regulation,improvement of the gut-liver axis interaction,modulation of immune and inflammatory pathways,enhancement of the adipose tissue-liver interaction,alleviation of fibrosis,prevention of hepatocyte injury,and traditional Chinese medicine(TCM)external therapies.Additionally,natural product research advancements,individual Chinese medicine components,and mixed herbal formulas for MAFLD treatment is provided.Many natural products and traditional Chinese medicines exhibit favorable effects in regulating lipid metabolism,anti-inflammation,and anti-oxidation,offering new directions and potential drug options for MAFLD treatment.This is expected to provide a reference for future clinical treatment and drug development.
基金Deutsche Forschungsgemeinschaft(DFG,German Research Foundation),project numbers 324633948 and 409784463(DFG grants Hi 678/9-3 and Hi 678/10-2,FOR2953)to HHBundesministerium für Bildung und Forschung-BMBF,project number 16LW0463K to HT.
文摘Microglia are the resident macrophages of the central nervous system.They act as the first line of defense against pathogens and play essential roles in neuroinflammation and tissue repair after brain insult or in neurodegenerative and demyelinating diseases(Borst et al.,2021).Together with infiltrating monocyte-derived macrophages,microglia also play a critical role for brain tumor development,since immunosuppressive interactions between tumor cells and tumor-associated microglia and macrophages(TAM)are linked to malignant progression.This mechanism is of particular relevance in glioblastoma(GB),the deadliest form of brain cancer with a median overall survival of less than 15 months(Khan et al.,2023).Therefore,targeting microglia and macrophage activation is a promising strategy for therapeutic interference in brain disease.
文摘Obesity is widely recognized as a global epidemic,primarily driven by an imbalance between energy expenditure and caloric intake associated with a sedentary lifestyle.Diets high in carbohydrates and saturated fats,particularly palmitic acid,are potent inducers of chronic low-grade inflammation,largely due to disruptions in glucose metabolism and the onset of insulin resistance(Qiu et al.,2022).While many organs are affected,the brain,specifically the hypothalamus,is among the first to exhibit inflammation in response to an unhealthy diet,suggesting that obesity may,in fact,be a brain-centered disease with neuroinflammation as a central factor(Thaler et al., 2012).
