Burial dissolution is a critical diagenetic process influencing ultra-deep carbonate reservoir development and preservation.Artificial carbonate samples with different internal structures were prepared,and high-temper...Burial dissolution is a critical diagenetic process influencing ultra-deep carbonate reservoir development and preservation.Artificial carbonate samples with different internal structures were prepared,and high-temperature and highpressure dissolution kinetic simulations were conducted.The results demonstrate that the intensity of burial dissolution is controlled by temperature and pressure,while tectonic-fluid activity influences the development pattern of burial dissolution,ultimately determining the direction of its differential modification.Extensive burial dissolution is likely to occur primarily at relatively shallow depths,significantly influencing reservoir formation,preservation,modification,and adjustment.The development of faults facilitates the maintenance of the intensity of burial dissolution.The maximum intensity of burial dissolution occurs at the tips and overlap zones of faults and intersections of multiple faults.The larger the scale of the faults,the more conducive it is to the development of burial dissolution.Burial dissolution fosters the formation of fault networks characterized by enhanced reservoir capacity and permeability.Burial dissolution controlled by episodic tectonic-fluid activity is a plausible explanation for forming the Tarim Basin's ultra-deep fault-controlled“stringbead-like”reservoirs.展开更多
The dominated contradiction in optimizing the performance of magnesium-air battery anode lies in the difficulty of achieving a good balance between activation and passivation during discharge process.To further reconci...The dominated contradiction in optimizing the performance of magnesium-air battery anode lies in the difficulty of achieving a good balance between activation and passivation during discharge process.To further reconcile this contradiction,two Mg-0.1Sc-0.1Y-0.1Ag anodes with different residual strain distribution through extrusion with/without annealing are fabricated.The results indicate that annealing can significantly lessen the“pseudo-anode”regions,thereby changing the dissolution mode of the matrix and achieving an effective dissolution during discharge.Additionally,p-type semiconductor characteristic of discharge productfilm could suppress the self-corrosion reaction without reducing the polarization of anode.The magnesium-air battery utilizing annealed Mg-0.1Sc-0.1Y-0.1Ag as anode achieves a synergistic improvement in specific capacity(1388.89 mA h g^(-1))and energy density(1960.42 mW h g^(-1)).This anode modification method accelerates the advancement of high efficiency and long lifespan magnesium-air batteries,offering renewable and cost-effective energy solutions for electronics and emergency equipment.展开更多
The dissolution behavior of complex inclusions in refining slag was studied using confocal laser scanning microscope.Based on the dissolution curve of complex inclusions,the main rate-limiting link of CaO-SiO_(2)-Al_(...The dissolution behavior of complex inclusions in refining slag was studied using confocal laser scanning microscope.Based on the dissolution curve of complex inclusions,the main rate-limiting link of CaO-SiO_(2)-Al_(2)O_(3)complex inclusions was the diffusion in the molten slag.The dissolution rate of CaO-SiO_(2)-Al_(2)O_(3)complex inclusions was affected by the composition and size of inclusion.The functional relationship between the dimensionless inclusion capacity(Zh)and the dimensionless dissolution rate(Ry)of CaO-SiO_(2)-Al_(2)O_(3)complex inclusions was calculated as Ry=2.10×10^(-6)Zh^(0.160),while it was Ry=2.10×10^(-6)Zh^(0.0087)for Al_(2)O_(3)-CaO complex inclusions.On this basis,the complete dissolution time and rate of the complex inclusions were calculated by using the function relation between the Zh and Ry numbers.展开更多
Global coral reef ecosystems have been severely degraded due to the combined effects of climate change and human activities.Changes in the seawater carbonate system of coral reef ecosystems can reflect their status an...Global coral reef ecosystems have been severely degraded due to the combined effects of climate change and human activities.Changes in the seawater carbonate system of coral reef ecosystems can reflect their status and their responses to the impacts of climate change and human activities.Winter and summer surveys in 2019 found that the ecological community of the Luhuitou coral reef flat was dominated by macroalgae and corals,respectively,contrasting with the conditions 10 years ago.The Luhuitou fringing reefs were sources of atmospheric CO_(2) in both seasons.In winter,the daily variation range of dissolved inorganic carbon(DIC)in Luhuitou coral reefs was up to 450μmol/kg,while that of total alkalinity(TA)was only 68μmol/kg.This indicated that the organic production was significantly higher than the calcification process during this period.The TA/DIC was approximately 0.15,which was less than half of that in healthy coral reefs;hence,photosynthesis-respiration processes were the most important factors controlling daily changes in the seawater carbonate system.The net community production(NCP)of the Luhuitou coral reef ecosystem in winter was as high as 47.65 mmol C/(m^(2)·h).While the net community calcification(NCC)was approximately 3.35 and-4.15 mmol CaCO_(3)/(m^(2)·h)during the daytime and nighttime respectively.Therefore,the NCC for the entire day was-21.9 mmol CaCO_(3)/(m^(2)·d),indicating a net autotrophic dissolved state.In summer,the acidification was enhanced by thunderstorms and heavy rain with the highest seawater partial pressure of CO_(2)(p CO_(2))and lowest pH T.Over the past 10 years,the increase rate of seawater p CO_(2) in Luhuitou reef was approximately 13.3μatm/a***,six times that of the open ocean,while the decrease rate of pH was approximately 0.0083/a,being five times that of the global ocean.These findings underscore the importance of protecting and restoring Luhuitou fringing reef,as well as similar reefs worldwide.展开更多
In a hydrogen-rich blast furnace,an increased coke load accentuates the support skeleton role of coke,particularly in the cohesive and dripping zones following partial dissolution with slag.To investigate the dissolut...In a hydrogen-rich blast furnace,an increased coke load accentuates the support skeleton role of coke,particularly in the cohesive and dripping zones following partial dissolution with slag.To investigate the dissolution behaviours of coke in these regions,coke samples were gasified in a N2-CO-CO_(2)-H_(2)-H_(2)O atmosphere,simulating hydrogen-rich blast furnace conditions.Subsequently,the dissolution of gasified coke with slag containing FeO was analysed.The influence of coke gasification degree and FeO concentration in slag on coke dissolution was examined.The results showed that both higher coke gasification degrees and increased FeO content accelerate coke mass loss and exacerbate surface degradation upon dissolution,while effects on the internal structure of coke remain relatively minor,especially regarding FeO concentration.Additionally,hydrogen-rich gasification raised the graphitisation level of coke,with dissolution further enhancing the graphitisation of gasified coke.展开更多
The widespread use of plastic waste has caused significant environmental pollution,becoming a focal point of global concern,particularly the challenge of dechlorination in mixed plastic waste.Selective dissolution is ...The widespread use of plastic waste has caused significant environmental pollution,becoming a focal point of global concern,particularly the challenge of dechlorination in mixed plastic waste.Selective dissolution is a promising plastic chemical recycling technology that offers benefits such as simple processes,convenient operation,and recyclable solvents.However,selecting suitable solvents remains a challenge.This study establishes a virtual solvent database containing 530 common inorganic and organic solvents.By calculating theσ-profile of polyvinyl chloride(PVC)and polyethylene(PE)models using quantum mechanical calculations and employing the conductor-like screening model for real solvents(COSMO-RS)method,the solubility performance of these solvents for PVC and PE at different temperatures was predicted.The results demonstrate the high accuracy of the COSMO-RS method in predicting solubility.By comparing the solubility differences between PVC and PE in different solvents,a series of solvents suitable for selectively removing PVC from mixed plastics were identified,for example,N-methyl-2-pyrrolidone(NMP),dimethyl sulfoxide(DMSO),tetrahydrofuran(THF),and N,Ndimethylacetamide(DMAc).This method provides a novel solution to the solvent selection challenge in plastic chemical recycling,potentially shortening the research and development period,reducing experimental costs,and promoting the development of green and refined waste plastic recycling processes.展开更多
This work investigated the original microstructure of cold-worked alumina-forming austenitic steel,along with its precipitation and dissolution corrosion behaviors in lead-bismuth eutectic with 10-8 wt.%oxygen at 600...This work investigated the original microstructure of cold-worked alumina-forming austenitic steel,along with its precipitation and dissolution corrosion behaviors in lead-bismuth eutectic with 10-8 wt.%oxygen at 600℃,using solution-annealed steel for comparison.Anomalously,cold-worked steel presented milder corrosion compared to solution-annealed steel,with average corrosion depths of 314.3 and 401.0μm after 1700 h exposure.Cold working-induced de-twinning transformed the annealing twin boundaries into normal high-angle grain boundaries(NGBs),increasing NGBs proportion from 36%to 89%.The increased NGBs provided more nucleation sites for intergranular barriers composed of alternate NiAl and M23C6 precipitates,thus better obstructing the dissolution attack.展开更多
Natural phosphates(Apatite)are the main sources of phosphorus,one of the three major chemical elements for plant development.The present work aims to study the efficiency of dissolution of natural phosphate from Togo ...Natural phosphates(Apatite)are the main sources of phosphorus,one of the three major chemical elements for plant development.The present work aims to study the efficiency of dissolution of natural phosphate from Togo during composting of a mixture of this ore with different types of vegetal matter.Phospho-composts of mixtures of ore and cow dung(A+P),poultry droppings(B+P),nymphea(C+P),domestic organic waste(D+P)and vegetal organic composts without phosphate(A,B,C and D)were elaborated.Determination of available phosphorus concentrations by the colorimetry method(HACH DR 3800)in composts and phospho-composts was realized.Analysis results revealed that organic matter has a solubilizing effect on natural phosphate.Nymphea phospho-compost has the best ore dissolved because its assimilable phosphorus content is the highest(0.88%).These results also showed that phosphocomposts maturation time has a beneficial effect on the ore dissolution.展开更多
Magnesium implants have received widespread attention in orthopaedic surgery.However,the mechanical degradation and concurrent inflammation caused by the rapid corrosion of Mg limits their applications.In this study,a...Magnesium implants have received widespread attention in orthopaedic surgery.However,the mechanical degradation and concurrent inflammation caused by the rapid corrosion of Mg limits their applications.In this study,a kind of unique core-shell heterojunction CuS@PPy nanostructures was synthesized and then incorporated in polycaprolactone(PCL)to construct an intelligent coating(CuS@PPy/PCL)on micro-arc-oxidized Mg implants.The PCL-based coating can realize near-infrared(NIR)-driven antibacterial and controllable Mg dissolution according to different bone healing stages.At the beginning of bone remodelling,the coating exhibits promising antibacterial properties with 99.67%and 99.17%efficacy against S.aureus and E.coli,respectively,thanks to the singlet oxygen(^(1)O_(2))and alkoxyl radicals(RO·)generated by the photodynamic effect of CuS@PPy heterojunction under low-power NIR light(1.5 W/cm^(2)).In the bone reparative stage,the PCL-based coating can maintain high corrosion resistance to meet the mechanical requirements of Mg implants in human body fluid.However,after the complete rehabilitation of bones,through a high-power(2 W/cm^(2))NIR light,the PCL-based coating changed from an elastic to a viscous flow state(44.7℃)under the photothermal effects of CuS@PPy,leading to quick degradation of the PCL-based coating and following accelerating dissolution of the Mg implant(avoiding secondary surgery).Hopefully,this NIR-responsive coating may provide an innovative method for the antibacterial and controllable dissolution of Mg implants.展开更多
Complex physical and chemical reactions during CO_(2)sequestration alter the microscopic pore structure of geological formations,impacting sequestration stability.To investigate CO_(2)sequestration dynamics,comprehens...Complex physical and chemical reactions during CO_(2)sequestration alter the microscopic pore structure of geological formations,impacting sequestration stability.To investigate CO_(2)sequestration dynamics,comprehensive physical simulation experiments were conducted under varied pressures,coupled with assessments of changes in mineral composition,ion concentrations,pore morphology,permeability,and sequestration capacity before and after experimentation.Simultaneously,a method using NMR T2spectra changes to measure pore volume shift and estimate CO_(2)sequestration is introduced.It quantifies CO_(2)needed for mineralization of soluble minerals.However,when CO_(2)dissolves in crude oil,the precipitation of asphaltene compounds impairs both seepage and storage capacities.Notably,the impact of dissolution and precipitation is closely associated with storage pressure,with a particularly pronounced influence on smaller pores.As pressure levels rise,the magnitude of pore alterations progressively increases.At a pressure threshold of 25 MPa,the rate of change in small pores due to dissolution reaches a maximum of 39.14%,while precipitation results in a change rate of-58.05%for small pores.The observed formation of dissolution pores and micro-cracks during dissolution,coupled with asphaltene precipitation,provides crucial insights for establishing CO_(2)sequestration parameters and optimizing strategies in low permeability reservoirs.展开更多
Geological sequestration of carbon dioxide(CO_(2))entails the long-term storage of captured emissions from CCUS(Carbon Capture,Utilization,and Storage)facilities in deep saline aquifers to mitigate greenhouse gas accu...Geological sequestration of carbon dioxide(CO_(2))entails the long-term storage of captured emissions from CCUS(Carbon Capture,Utilization,and Storage)facilities in deep saline aquifers to mitigate greenhouse gas accumulation.Among various trapping mechanisms,dissolution trapping is particularly effective in enhancing storage security.However,the stratified structure of saline aquifers plays a crucial role in controlling the efficiency of CO_(2) dissolution into the resident brine.In this study,a two-dimensional numerical model of a stratified saline aquifer is developed,integrating both two-phase flow and mass transfer dynamics.The model captures the temporal evolution of gas saturation,reservoir pressure,and CO_(2) dissolution behavior under varying geological and operational conditions.Specifically,the effects of porosity heterogeneity,permeability distribution,and injection rate on the dissolution process are examined,and sequestration efficiencies across distinct stratigraphic layers are compared.Simulation results reveal that in the early phase of CO_(2) injection,the plume spreads radially along the lower portion of the aquifer.With continued injection,high-saturation regions expand upward and eventually accumulate beneath the shale and caprock layers.Pressure within the reservoir rises in response to CO_(2) injection,propagating both vertically and laterally.CO_(2) migration and dissolution are strongly influenced by reservoir properties,with progressive dissolution occurring in the pore spaces of individual layers.High-porosity zones favor CO_(2) accumulation and enhance local dissolution,whereas low-porosity regions facilitate vertical diffusion.An increase in porosity from 0.25 to 0.30 reduces the radial extent of dissolution in the high-permeability layer by 16.5%.Likewise,increasing permeability promotes radial dispersion;each 10 mD increment extends the CO_(2) dissolution front by approximately 18 m.Elevated injection rates intensify both vertical and lateral plume migration:every 0.25×10^(−6) m/s increase in rate yields an average 100–120 m increase in radial dissolution distance within high-permeability zones.展开更多
The dissolution behaviors of lime,limestone,and core–shell structured lime,as well as their effects on dephosphorization behavior were studied.The results show that the slow dissolution of lime in converter slag is m...The dissolution behaviors of lime,limestone,and core–shell structured lime,as well as their effects on dephosphorization behavior were studied.The results show that the slow dissolution of lime in converter slag is mainly attributed to the calcium silicate layer at the lime/slag interface.CO_(2)generated by CaCO_(3)decomposition can destroy the calcium silicate layer,and thus accelerates the dissolution of limestone and core–shell structured lime.However,in the initial stage,a large amount of CO_(2)emission generated by limestone decomposition results in the poor contact between molten slag and limestone,and the dissolution rate is slower in the test of limestone than that of lime.For core–shell structured lime,the initial dissolution rate is not affected due to the lime surface,and is accelerated by the appropriate CO_(2)emission.Rapid CaO pickup in molten slag by fast dissolution of the lime sample can remarkably accelerate the dephosphorization reaction.Because of the fastest dissolution rate,the core–shell structured lime slagging mode shows the most promising prospects for the efficient dephosphorization.展开更多
Dissolution kinetics of CaO·2Al_(2)O_(3)(CA_(2))particles in a synthetic CaO-Al_(2)O_(3)-SiO_(2)steelmaking slag system have been investigated using the high-temperature confocal laser scanning microscope.Effects...Dissolution kinetics of CaO·2Al_(2)O_(3)(CA_(2))particles in a synthetic CaO-Al_(2)O_(3)-SiO_(2)steelmaking slag system have been investigated using the high-temperature confocal laser scanning microscope.Effects of temperature(i.e.,1500,1550,and 1600℃)and slag composition on the dissolution time of CA_(2)particles are investigated,along with the time dependency of the projection area of the particle during the dissolution process.It is found that the dissolution rate was enhanced by either an increase in temperature or a decrease in slag viscosity.Moreover,a higher ratio of CaO/Al_(2)O_(3)(C/A)leads to an increased dissolution rate of CA_(2)particle at 1600℃.Thermodynamic calculations suggested the dissolution product,i.e.,melilite,formed on the surface of the CA_(2)particle during dissolution in slag with a C/A ratio of 3.8 at 1550℃.Scanning electron microscopy equipped with energy dispersive X-ray spectrometry analysis of as-quenched samples confirmed the dissolution path of CA_(2)particles in slags with C/A ratios of 1.8 and 3.8 as well as the melilite formed on the surface of CA_(2)particle.The formation of this layer during the dissolution process was identified as a hindrance,impeding the dissolution of CA_(2)particle.A valuable reference for designing or/and choosing the composition of top slag for clean steel production is provided,especially using calcium treatment during the secondary refining process.展开更多
The commercial ZK 60 magnesium alloy with extruded state experienced aging heat treatment(T 6)was dynamically loaded at strain rate of 3000 s−1 by means of the split Hopkinson pressure bar(SHPB)in this paper.Transmiss...The commercial ZK 60 magnesium alloy with extruded state experienced aging heat treatment(T 6)was dynamically loaded at strain rate of 3000 s−1 by means of the split Hopkinson pressure bar(SHPB)in this paper.Transmission electron microscopy(TEM)observations showed that the precipitatedβ′_(1) phases partially dissolved(spheroidized)with blurred interfaces within 160μs at 3000 s^(−1).The average length and diameter of the rod-shapedβ′_(1) phase particles were 48.5 and 9.8 nm after the T 6 heat treatment;while the average diameter of the sphericalβ′_(1) phases changed to 8.8 nm after loading.The deformedβ′_(1) phase generated larger lattice distortion energy than Mg matrix under high strain rate loading.Therefore,the difference of free energy(the driving force of dissolution)between theβ′_(1) phase and the matrix increased,making the instantaneous dissolution of theβ′_(1) phase thermodynamically feasible.The dissolution(spheroidization)of theβ′_(1) phase particles was kinetically promoted because the diffusion rate of the solute Zn atoms was accelerated by combined actions of adiabatic temperature rise,high density of dislocations(vacancies)and high deviatoric stresses during high strain rate loading.The increase in hardness of ZK 60-T 6 alloy could be attributed to solid solution strengthening,dislocation strengthening and second phase particle strengthening.展开更多
Copper-nickel tailings(CNTs),consisting of more than 80wt%magnesium-bearing silicate minerals,show great potential for CO_(2)mineral sequestration.The dissolution kinetics of CNTs in HCl solution was investigated thro...Copper-nickel tailings(CNTs),consisting of more than 80wt%magnesium-bearing silicate minerals,show great potential for CO_(2)mineral sequestration.The dissolution kinetics of CNTs in HCl solution was investigated through a leaching experiment and kinetic modeling,and the effects of reaction time,HCl concentration,solid-to-liquid ratio,and reaction temperature on the leaching rate of mag-nesium were comprehensively studied.Results show that the suitable leaching conditions for magnesium in CNTs are 2 M HCl,a solid-to-liquid ratio of 50 g·L^(−1),and 90℃,at which the maximum leaching rate of magnesium is as high as 83.88%.A modified shrinking core model can well describe the leaching kinetics of magnesium.The dissolution of magnesium was dominated by a combination of chemical reaction and product layer diffusion,with a calculated apparent activation energy of 77.51 kJ·mol^(−1).This study demonstrates the feasibil-ity of using CNTs as a media for CO_(2)mineral sequestration.展开更多
Tufa is an important type of landscape in karst regions.In recent years,the loss of landscape diversity due to tufa dissolution is affecting the stability of local ecosystems.Therefore,determining the factors and thei...Tufa is an important type of landscape in karst regions.In recent years,the loss of landscape diversity due to tufa dissolution is affecting the stability of local ecosystems.Therefore,determining the factors and their mechanisms involved in tufa dissolution is important for preserving regional landscape diversity and local ecosystem stability.In this study,we selected four tufa sites with different degrees of dissolution(undissolved tufa,lightly dissolved tufa,moderately dissolved tufa,and heavily dissolved tufa)in Xiangzhigou karst region of Guizhou Province as the study objects.We explored the effects of natural plant colonization on tufa dissolution using changes inαandβdiversity indices,soil physicochemical indicators,tufa components,and tufa substrate.The results indicated that the Shannon-wiener index,Simpson index and Patrick richness index gradually increased with tufa's increasing degree of dissolution.Additionally,the dissolution degree exhibited a significantly negative correlation with the species diversity(p<0.05).Natural vegetation colonization is the primary cause of changes in the proportion of tufa components and changes in the physicochemical properties of overlying tufa soils.The proportion of CaO components decreased significantly,and the proportion of loss on ignition components increased significantly.Soil organic carbon,pH,total nitrogen,available nitrogen,total phosphorus,available phosphorus,total potassium,available potassium,β-glucosidase,and urease gradually increased with deeper tufa dissolution and were negatively correlated with the degree of dissolution(p<0.05).It indicates that tufa is a process of dissolution into the soil and gradual improvement of the physicochemical properties of the overlying soil.Furthermore,scanning electron micrographs revealed the transition from dense to fragmented tufa structure under the influence of plants.In conclusion,this study found that improving plant diversity exacerbated tufa dissolution.Our findings provide a theoretical reference for the preventing and controlling of tufa dissolution in karst.展开更多
In the present study, we investigated the complexation of risperidone with hydroxypropyl-β-cyclodextrin （HP-β-CD） in aqueous solution due to the poor water solubility and low oral bioavailability of risperidone in...In the present study, we investigated the complexation of risperidone with hydroxypropyl-β-cyclodextrin （HP-β-CD） in aqueous solution due to the poor water solubility and low oral bioavailability of risperidone in humans. The effect of temperature on the complexation was examined, and thermodynamic parameters of the complexation process, such as Gibbs free energy change （AG）, enthalpy change （AH） and entropy change （AS）, were also explored. Meantime, the solid dispersion of risperidone with HP-β-CD was prepared and confirmed by Fourier IR spectroscopy and X-ray diffractometry. The experimental results suggested that the complex of the drug with HP-β-CD at a molar ratio of 1：1 could form in aqueous solution, and the complexation was an endothermic and entropy-driven process. The risperidone-HP-β-CD solid dispersion exhibited a remarkable improvement in the dissolution rate of the drug. This might be attributed to the amorphous state, the enhanced wettability as well as the complex formation of the drug with HP-β-CD in aqueous solution.展开更多
AimTo study effects of PVP K30 on the aque ou s solubility and dissolution properties of daidzein. Methods To measure the aqueous solubility and dissolution rates of daidzein in three diffe rent states (within solid d...AimTo study effects of PVP K30 on the aque ou s solubility and dissolution properties of daidzein. Methods To measure the aqueous solubility and dissolution rates of daidzein in three diffe rent states (within solid dispersions, physical mixtures and as a pure drug) and investigate drug-polymer interactions in the solid state using X-ray powder d iffraction and fourier-transform infrared spectroscopy. Results The negative values of the Gibbs free energy and enthalpy of transfer explaine d the spontaneous transfer of daidzein from phosphate buffer solution (PBS) to a solution of PVP in PBS. X-ray powder diffraction patterns showed that the drug was in the amorphous state (ratio of the drug ∶ PVP<1∶5) when dispers ed i n PVP K30. The infrared spectra indicated there exist interactions between the O H of daidzein and the C=O of PVP K30. Conclusionthe dispersion of daidzein in PVP K30 considerably enhances the solubility and dissolution rat e.展开更多
Manganese-based material is a prospective cathode material for aqueous zinc ion batteries(ZIBs)by virtue of its high theoretical capacity,high operating voltage,and low price.However,the manganese dissolution during t...Manganese-based material is a prospective cathode material for aqueous zinc ion batteries(ZIBs)by virtue of its high theoretical capacity,high operating voltage,and low price.However,the manganese dissolution during the electrochemical reaction causes its electrochemical cycling stability to be undesirable.In this work,heterointerface engineering-induced oxygen defects are introduced into heterostructure MnO_(2)(δa-MnO_(2))by in situ electrochemical activation to inhibit manganese dissolution for aqueous zinc ion batteries.Meanwhile,the heterointerface between the disordered amorphous and the crystalline MnO_(2)ofδa-MnO_(2)is decisive for the formation of oxygen defects.And the experimental results indicate that the manganese dissolution ofδa-MnO_(2)is considerably inhibited during the charge/discharge cycle.Theoretical analysis indicates that the oxygen defect regulates the electronic and band structure and the Mn-O bonding state of the electrode material,thereby promoting electron transport kinetics as well as inhibiting Mn dissolution.Consequently,the capacity ofδa-MnO_(2)does not degrade after 100 cycles at a current density of 0.5 Ag^(-1)and also 91%capacity retention after 500cycles at 1 Ag^(-1).This study provides a promising insight into the development of high-performance manganese-based cathode materials through a facile and low-cost strategy.展开更多
To clarify the formation and distribution of feldspar dissolution pores and predict the distribution of high-quality reservoir in gravity flow sandstone of the 7^(th) member of Triassic Yanchang Formation(Chang 7 Memb...To clarify the formation and distribution of feldspar dissolution pores and predict the distribution of high-quality reservoir in gravity flow sandstone of the 7^(th) member of Triassic Yanchang Formation(Chang 7 Member)in the Ordos Basin,thin sections,scanning electron microscopy,energy spectrum analysis,X-ray diffraction whole rock analysis,and dissolution experiments are employed in this study to investigate the characteristics and control factors of feldspar dissolution pores.The results show that:(1)Three types of diagenetic processes are observed in the feldspar of Chang 7 sandstone in the study area:secondary overgrowth of feldspar,replacement by clay and calcite,and dissolution of detrital feldspar.(2)The feldspar dissolution of Chang 7 tight sandstone is caused by organic acid,and is further affected by the type of feldspar,the degree of early feldspar alteration,and the buffering effect of mica debris on organic acid.(3)Feldspars have varying degrees of dissolution.Potassium feldspar is more susceptible to dissolution than plagioclase.Among potassium feldspar,orthoclase is more soluble than microcline,and unaltered feldspar is more soluble than early kaolinized or sericitized feldspar.(4)The dissolution experiment demonstrated that the presence of mica can hinder the dissolution of feldspar.Mica of the same mass has a significantly stronger capacity to consume organic acids than feldspar.(5)Dissolution pores in feldspar of Chang 7 Member are more abundant in areas with low mica content,and they improve the reservoir physical properties,while in areas with high mica content,the number of feldspar dissolution pores decreases significantly.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.U21B2062)supported by the Key Laboratory for Carbonate Reservoirs of China National Petroleum Corporation。
文摘Burial dissolution is a critical diagenetic process influencing ultra-deep carbonate reservoir development and preservation.Artificial carbonate samples with different internal structures were prepared,and high-temperature and highpressure dissolution kinetic simulations were conducted.The results demonstrate that the intensity of burial dissolution is controlled by temperature and pressure,while tectonic-fluid activity influences the development pattern of burial dissolution,ultimately determining the direction of its differential modification.Extensive burial dissolution is likely to occur primarily at relatively shallow depths,significantly influencing reservoir formation,preservation,modification,and adjustment.The development of faults facilitates the maintenance of the intensity of burial dissolution.The maximum intensity of burial dissolution occurs at the tips and overlap zones of faults and intersections of multiple faults.The larger the scale of the faults,the more conducive it is to the development of burial dissolution.Burial dissolution fosters the formation of fault networks characterized by enhanced reservoir capacity and permeability.Burial dissolution controlled by episodic tectonic-fluid activity is a plausible explanation for forming the Tarim Basin's ultra-deep fault-controlled“stringbead-like”reservoirs.
基金the National Natural Science:Foundation of China(52375370)the Open Project of Salt Lake Chemical Engineering Research Complex,Qinghai University(2023-DXSSKF-Z02)+2 种基金the Nat-ural Science Foundation of Shanxi(202103021224049)GDAS Projects of International cooperation platform of Sci-ence and Technology(2022GDASZH-2022010203-003)Guangdong province Science and Technology Plan Projects(2023B1212060045).
文摘The dominated contradiction in optimizing the performance of magnesium-air battery anode lies in the difficulty of achieving a good balance between activation and passivation during discharge process.To further reconcile this contradiction,two Mg-0.1Sc-0.1Y-0.1Ag anodes with different residual strain distribution through extrusion with/without annealing are fabricated.The results indicate that annealing can significantly lessen the“pseudo-anode”regions,thereby changing the dissolution mode of the matrix and achieving an effective dissolution during discharge.Additionally,p-type semiconductor characteristic of discharge productfilm could suppress the self-corrosion reaction without reducing the polarization of anode.The magnesium-air battery utilizing annealed Mg-0.1Sc-0.1Y-0.1Ag as anode achieves a synergistic improvement in specific capacity(1388.89 mA h g^(-1))and energy density(1960.42 mW h g^(-1)).This anode modification method accelerates the advancement of high efficiency and long lifespan magnesium-air batteries,offering renewable and cost-effective energy solutions for electronics and emergency equipment.
基金support from the National Key R&D Program(No.2023YFB3709900)the National Natural Science Foundation of China(Grant No.U22A20171)+1 种基金the High Steel Center at the North China University of Technologythe University of Science and Technology Beijing,China.
文摘The dissolution behavior of complex inclusions in refining slag was studied using confocal laser scanning microscope.Based on the dissolution curve of complex inclusions,the main rate-limiting link of CaO-SiO_(2)-Al_(2)O_(3)complex inclusions was the diffusion in the molten slag.The dissolution rate of CaO-SiO_(2)-Al_(2)O_(3)complex inclusions was affected by the composition and size of inclusion.The functional relationship between the dimensionless inclusion capacity(Zh)and the dimensionless dissolution rate(Ry)of CaO-SiO_(2)-Al_(2)O_(3)complex inclusions was calculated as Ry=2.10×10^(-6)Zh^(0.160),while it was Ry=2.10×10^(-6)Zh^(0.0087)for Al_(2)O_(3)-CaO complex inclusions.On this basis,the complete dissolution time and rate of the complex inclusions were calculated by using the function relation between the Zh and Ry numbers.
基金Supported by the National Key Research and Development Program of China(Nos.2021YFC3100500,2022YFC3103602,2021YFF0502800)the National Natural Science Foundation of China(No.U23A2035)+3 种基金the Science and Technology Planning Project of Guangdong Province,China(No.2023B1212060047)the State Key Laboratory of Tropical Oceanography,South China Sea Institute of Oceanology,Chinese Academy of Sciences(No.LTO1919)the Visiting Fellowship Program of the State Key Laboratory of Marine Environmental Science,Xiamen University(No.MELRS1914)the Hainan Province Key R&D Program(No.ZDYF2023SHFZ131)。
文摘Global coral reef ecosystems have been severely degraded due to the combined effects of climate change and human activities.Changes in the seawater carbonate system of coral reef ecosystems can reflect their status and their responses to the impacts of climate change and human activities.Winter and summer surveys in 2019 found that the ecological community of the Luhuitou coral reef flat was dominated by macroalgae and corals,respectively,contrasting with the conditions 10 years ago.The Luhuitou fringing reefs were sources of atmospheric CO_(2) in both seasons.In winter,the daily variation range of dissolved inorganic carbon(DIC)in Luhuitou coral reefs was up to 450μmol/kg,while that of total alkalinity(TA)was only 68μmol/kg.This indicated that the organic production was significantly higher than the calcification process during this period.The TA/DIC was approximately 0.15,which was less than half of that in healthy coral reefs;hence,photosynthesis-respiration processes were the most important factors controlling daily changes in the seawater carbonate system.The net community production(NCP)of the Luhuitou coral reef ecosystem in winter was as high as 47.65 mmol C/(m^(2)·h).While the net community calcification(NCC)was approximately 3.35 and-4.15 mmol CaCO_(3)/(m^(2)·h)during the daytime and nighttime respectively.Therefore,the NCC for the entire day was-21.9 mmol CaCO_(3)/(m^(2)·d),indicating a net autotrophic dissolved state.In summer,the acidification was enhanced by thunderstorms and heavy rain with the highest seawater partial pressure of CO_(2)(p CO_(2))and lowest pH T.Over the past 10 years,the increase rate of seawater p CO_(2) in Luhuitou reef was approximately 13.3μatm/a***,six times that of the open ocean,while the decrease rate of pH was approximately 0.0083/a,being five times that of the global ocean.These findings underscore the importance of protecting and restoring Luhuitou fringing reef,as well as similar reefs worldwide.
基金the financial support provided by the National Natural Science Foundation of China(Nos.52174300 and 52404340)Science and Technology Innovation Key R&D Program of Chongqing,China(No.CSTB2024TIAD-STX0009)+3 种基金The Science and Technology Research Program of Chongqing Municipal Education Commission(No.KJQN202401507)Chongqing Talent Plan Project(cstc2021ycjh-bgzxm0211)Natural Science Foundation of Chongqing,China(No.CSTB2024NSCQ-LZX0052)Chongqing Doctoral“Through Train”Project(No.sl202100000343).
文摘In a hydrogen-rich blast furnace,an increased coke load accentuates the support skeleton role of coke,particularly in the cohesive and dripping zones following partial dissolution with slag.To investigate the dissolution behaviours of coke in these regions,coke samples were gasified in a N2-CO-CO_(2)-H_(2)-H_(2)O atmosphere,simulating hydrogen-rich blast furnace conditions.Subsequently,the dissolution of gasified coke with slag containing FeO was analysed.The influence of coke gasification degree and FeO concentration in slag on coke dissolution was examined.The results showed that both higher coke gasification degrees and increased FeO content accelerate coke mass loss and exacerbate surface degradation upon dissolution,while effects on the internal structure of coke remain relatively minor,especially regarding FeO concentration.Additionally,hydrogen-rich gasification raised the graphitisation level of coke,with dissolution further enhancing the graphitisation of gasified coke.
基金financially supported by SINOPEC Research Institute of Petroleum Processing Co.,Ltd.the National Natural Science Foundation of China(22302220)+2 种基金the Shanxi Province Science Foundation for Youth(202203021222403)Funding support was also received from the Synfuels China Co.,Ltd.the Institute of Coal Chemistry,Chinese Academy of Sciences。
文摘The widespread use of plastic waste has caused significant environmental pollution,becoming a focal point of global concern,particularly the challenge of dechlorination in mixed plastic waste.Selective dissolution is a promising plastic chemical recycling technology that offers benefits such as simple processes,convenient operation,and recyclable solvents.However,selecting suitable solvents remains a challenge.This study establishes a virtual solvent database containing 530 common inorganic and organic solvents.By calculating theσ-profile of polyvinyl chloride(PVC)and polyethylene(PE)models using quantum mechanical calculations and employing the conductor-like screening model for real solvents(COSMO-RS)method,the solubility performance of these solvents for PVC and PE at different temperatures was predicted.The results demonstrate the high accuracy of the COSMO-RS method in predicting solubility.By comparing the solubility differences between PVC and PE in different solvents,a series of solvents suitable for selectively removing PVC from mixed plastics were identified,for example,N-methyl-2-pyrrolidone(NMP),dimethyl sulfoxide(DMSO),tetrahydrofuran(THF),and N,Ndimethylacetamide(DMAc).This method provides a novel solution to the solvent selection challenge in plastic chemical recycling,potentially shortening the research and development period,reducing experimental costs,and promoting the development of green and refined waste plastic recycling processes.
基金supported by the Nuclear Technology R&D Program.
文摘This work investigated the original microstructure of cold-worked alumina-forming austenitic steel,along with its precipitation and dissolution corrosion behaviors in lead-bismuth eutectic with 10-8 wt.%oxygen at 600℃,using solution-annealed steel for comparison.Anomalously,cold-worked steel presented milder corrosion compared to solution-annealed steel,with average corrosion depths of 314.3 and 401.0μm after 1700 h exposure.Cold working-induced de-twinning transformed the annealing twin boundaries into normal high-angle grain boundaries(NGBs),increasing NGBs proportion from 36%to 89%.The increased NGBs provided more nucleation sites for intergranular barriers composed of alternate NiAl and M23C6 precipitates,thus better obstructing the dissolution attack.
基金SIGMA Scientific Group and Mohamed VI Polytechnic University for their financial support.
文摘Natural phosphates(Apatite)are the main sources of phosphorus,one of the three major chemical elements for plant development.The present work aims to study the efficiency of dissolution of natural phosphate from Togo during composting of a mixture of this ore with different types of vegetal matter.Phospho-composts of mixtures of ore and cow dung(A+P),poultry droppings(B+P),nymphea(C+P),domestic organic waste(D+P)and vegetal organic composts without phosphate(A,B,C and D)were elaborated.Determination of available phosphorus concentrations by the colorimetry method(HACH DR 3800)in composts and phospho-composts was realized.Analysis results revealed that organic matter has a solubilizing effect on natural phosphate.Nymphea phospho-compost has the best ore dissolved because its assimilable phosphorus content is the highest(0.88%).These results also showed that phosphocomposts maturation time has a beneficial effect on the ore dissolution.
基金support to this work:the National Natural Science Foundation of China(grant No.50971064,No.51361004)the Innovative Foundation of HUST(grant 2017KFYXJJ164).
文摘Magnesium implants have received widespread attention in orthopaedic surgery.However,the mechanical degradation and concurrent inflammation caused by the rapid corrosion of Mg limits their applications.In this study,a kind of unique core-shell heterojunction CuS@PPy nanostructures was synthesized and then incorporated in polycaprolactone(PCL)to construct an intelligent coating(CuS@PPy/PCL)on micro-arc-oxidized Mg implants.The PCL-based coating can realize near-infrared(NIR)-driven antibacterial and controllable Mg dissolution according to different bone healing stages.At the beginning of bone remodelling,the coating exhibits promising antibacterial properties with 99.67%and 99.17%efficacy against S.aureus and E.coli,respectively,thanks to the singlet oxygen(^(1)O_(2))and alkoxyl radicals(RO·)generated by the photodynamic effect of CuS@PPy heterojunction under low-power NIR light(1.5 W/cm^(2)).In the bone reparative stage,the PCL-based coating can maintain high corrosion resistance to meet the mechanical requirements of Mg implants in human body fluid.However,after the complete rehabilitation of bones,through a high-power(2 W/cm^(2))NIR light,the PCL-based coating changed from an elastic to a viscous flow state(44.7℃)under the photothermal effects of CuS@PPy,leading to quick degradation of the PCL-based coating and following accelerating dissolution of the Mg implant(avoiding secondary surgery).Hopefully,this NIR-responsive coating may provide an innovative method for the antibacterial and controllable dissolution of Mg implants.
基金support of the National Natural Science Foundation of China(Grant Nos.52174030,52474042 and 52374041)the Postgraduate Innovation Fund Project of Xi'an Shiyou University(No.YCX2411001)the Natural Science Basic Research Program of Shaanxi(Program Nos.2024JCYBMS-256 and 2022JQ-528)。
文摘Complex physical and chemical reactions during CO_(2)sequestration alter the microscopic pore structure of geological formations,impacting sequestration stability.To investigate CO_(2)sequestration dynamics,comprehensive physical simulation experiments were conducted under varied pressures,coupled with assessments of changes in mineral composition,ion concentrations,pore morphology,permeability,and sequestration capacity before and after experimentation.Simultaneously,a method using NMR T2spectra changes to measure pore volume shift and estimate CO_(2)sequestration is introduced.It quantifies CO_(2)needed for mineralization of soluble minerals.However,when CO_(2)dissolves in crude oil,the precipitation of asphaltene compounds impairs both seepage and storage capacities.Notably,the impact of dissolution and precipitation is closely associated with storage pressure,with a particularly pronounced influence on smaller pores.As pressure levels rise,the magnitude of pore alterations progressively increases.At a pressure threshold of 25 MPa,the rate of change in small pores due to dissolution reaches a maximum of 39.14%,while precipitation results in a change rate of-58.05%for small pores.The observed formation of dissolution pores and micro-cracks during dissolution,coupled with asphaltene precipitation,provides crucial insights for establishing CO_(2)sequestration parameters and optimizing strategies in low permeability reservoirs.
基金supported by the National Natural Science Foundation of China(No.52306187)the Fundamental Research Funds for the Central Universities of China(Grant No.3132024205)the Open Fund of Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education(Grant No.LOEC-202004).
文摘Geological sequestration of carbon dioxide(CO_(2))entails the long-term storage of captured emissions from CCUS(Carbon Capture,Utilization,and Storage)facilities in deep saline aquifers to mitigate greenhouse gas accumulation.Among various trapping mechanisms,dissolution trapping is particularly effective in enhancing storage security.However,the stratified structure of saline aquifers plays a crucial role in controlling the efficiency of CO_(2) dissolution into the resident brine.In this study,a two-dimensional numerical model of a stratified saline aquifer is developed,integrating both two-phase flow and mass transfer dynamics.The model captures the temporal evolution of gas saturation,reservoir pressure,and CO_(2) dissolution behavior under varying geological and operational conditions.Specifically,the effects of porosity heterogeneity,permeability distribution,and injection rate on the dissolution process are examined,and sequestration efficiencies across distinct stratigraphic layers are compared.Simulation results reveal that in the early phase of CO_(2) injection,the plume spreads radially along the lower portion of the aquifer.With continued injection,high-saturation regions expand upward and eventually accumulate beneath the shale and caprock layers.Pressure within the reservoir rises in response to CO_(2) injection,propagating both vertically and laterally.CO_(2) migration and dissolution are strongly influenced by reservoir properties,with progressive dissolution occurring in the pore spaces of individual layers.High-porosity zones favor CO_(2) accumulation and enhance local dissolution,whereas low-porosity regions facilitate vertical diffusion.An increase in porosity from 0.25 to 0.30 reduces the radial extent of dissolution in the high-permeability layer by 16.5%.Likewise,increasing permeability promotes radial dispersion;each 10 mD increment extends the CO_(2) dissolution front by approximately 18 m.Elevated injection rates intensify both vertical and lateral plume migration:every 0.25×10^(−6) m/s increase in rate yields an average 100–120 m increase in radial dissolution distance within high-permeability zones.
基金gratefully acknowledge the support from National Natural Science Foundation of China(Nos.52274305,52374309 and 52004189)Project of Hubei Provincial Department of Science and Technology(No.2022BAA021)+2 种基金China Postdoctoral Science Foundation(Nos.2023T160210 and 2022M721109)Young Elite Scientists Sponsorship Program by CAST(No.2022QNRC001)Open Foundation of Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education(FMRUlab-25-05).
文摘The dissolution behaviors of lime,limestone,and core–shell structured lime,as well as their effects on dephosphorization behavior were studied.The results show that the slow dissolution of lime in converter slag is mainly attributed to the calcium silicate layer at the lime/slag interface.CO_(2)generated by CaCO_(3)decomposition can destroy the calcium silicate layer,and thus accelerates the dissolution of limestone and core–shell structured lime.However,in the initial stage,a large amount of CO_(2)emission generated by limestone decomposition results in the poor contact between molten slag and limestone,and the dissolution rate is slower in the test of limestone than that of lime.For core–shell structured lime,the initial dissolution rate is not affected due to the lime surface,and is accelerated by the appropriate CO_(2)emission.Rapid CaO pickup in molten slag by fast dissolution of the lime sample can remarkably accelerate the dephosphorization reaction.Because of the fastest dissolution rate,the core–shell structured lime slagging mode shows the most promising prospects for the efficient dephosphorization.
基金the Natural Sciences and Engineering Research Council of Canada(NSERC)for funding this researchThis research used a high temperature confocal laser scanning microscope-VL2000DX-SVF17SP funded by Canada Foundation for Innovation John Evans Leaders Fund(CFI JELF,Project Number:32826),a PANalytical X’Pert diffraction instrument located at the Centre for crystal growth,Brockhouse Institute for Materials Research,and a scanning electron microscope-JEOL 6610 located at the Canadian Centre for Electron Microscopy at McMaster University.W.Mu would like to acknowledge Swedish Iron and Steel Research Office(Jernkonteret),STINT and SSF for supporting the time for international collaboration research regarding clean steel.
文摘Dissolution kinetics of CaO·2Al_(2)O_(3)(CA_(2))particles in a synthetic CaO-Al_(2)O_(3)-SiO_(2)steelmaking slag system have been investigated using the high-temperature confocal laser scanning microscope.Effects of temperature(i.e.,1500,1550,and 1600℃)and slag composition on the dissolution time of CA_(2)particles are investigated,along with the time dependency of the projection area of the particle during the dissolution process.It is found that the dissolution rate was enhanced by either an increase in temperature or a decrease in slag viscosity.Moreover,a higher ratio of CaO/Al_(2)O_(3)(C/A)leads to an increased dissolution rate of CA_(2)particle at 1600℃.Thermodynamic calculations suggested the dissolution product,i.e.,melilite,formed on the surface of the CA_(2)particle during dissolution in slag with a C/A ratio of 3.8 at 1550℃.Scanning electron microscopy equipped with energy dispersive X-ray spectrometry analysis of as-quenched samples confirmed the dissolution path of CA_(2)particles in slags with C/A ratios of 1.8 and 3.8 as well as the melilite formed on the surface of CA_(2)particle.The formation of this layer during the dissolution process was identified as a hindrance,impeding the dissolution of CA_(2)particle.A valuable reference for designing or/and choosing the composition of top slag for clean steel production is provided,especially using calcium treatment during the secondary refining process.
基金Projects(51871243,51574290)supported by the National Natural Science Foundation of ChinaProject(ASSIKFJJ202304001)supported by the Open Fund of the National Key Laboratory of Strength and Structural Integrity,China+3 种基金Project(HT-CSNS-DG-CD-0092/2021)supported by the Guangdong-Hong Kong-Macao Joint Laboratory for Neutron Scattering Science and Technology,ChinaProject(2022KF-08)supported by the Hubei Longzhong Laboratory,ChinaProject(22kfgk06)supported by the Shock and Vibration of Engineering Materials and Structures Key Laboratory of Sichuan Province,ChinaProject(PBSKL2022C01)supported by the State Key Laboratory of Precision Blasting and Hubei Key Laboratory of Blasting Engineering,China。
文摘The commercial ZK 60 magnesium alloy with extruded state experienced aging heat treatment(T 6)was dynamically loaded at strain rate of 3000 s−1 by means of the split Hopkinson pressure bar(SHPB)in this paper.Transmission electron microscopy(TEM)observations showed that the precipitatedβ′_(1) phases partially dissolved(spheroidized)with blurred interfaces within 160μs at 3000 s^(−1).The average length and diameter of the rod-shapedβ′_(1) phase particles were 48.5 and 9.8 nm after the T 6 heat treatment;while the average diameter of the sphericalβ′_(1) phases changed to 8.8 nm after loading.The deformedβ′_(1) phase generated larger lattice distortion energy than Mg matrix under high strain rate loading.Therefore,the difference of free energy(the driving force of dissolution)between theβ′_(1) phase and the matrix increased,making the instantaneous dissolution of theβ′_(1) phase thermodynamically feasible.The dissolution(spheroidization)of theβ′_(1) phase particles was kinetically promoted because the diffusion rate of the solute Zn atoms was accelerated by combined actions of adiabatic temperature rise,high density of dislocations(vacancies)and high deviatoric stresses during high strain rate loading.The increase in hardness of ZK 60-T 6 alloy could be attributed to solid solution strengthening,dislocation strengthening and second phase particle strengthening.
基金finacially supported by the National Key Research and Development Program of China(No.2022YFE0135100)the National Natural Science Found-ation of China(Nos.52378255,52278270,and 52008151).
文摘Copper-nickel tailings(CNTs),consisting of more than 80wt%magnesium-bearing silicate minerals,show great potential for CO_(2)mineral sequestration.The dissolution kinetics of CNTs in HCl solution was investigated through a leaching experiment and kinetic modeling,and the effects of reaction time,HCl concentration,solid-to-liquid ratio,and reaction temperature on the leaching rate of mag-nesium were comprehensively studied.Results show that the suitable leaching conditions for magnesium in CNTs are 2 M HCl,a solid-to-liquid ratio of 50 g·L^(−1),and 90℃,at which the maximum leaching rate of magnesium is as high as 83.88%.A modified shrinking core model can well describe the leaching kinetics of magnesium.The dissolution of magnesium was dominated by a combination of chemical reaction and product layer diffusion,with a calculated apparent activation energy of 77.51 kJ·mol^(−1).This study demonstrates the feasibil-ity of using CNTs as a media for CO_(2)mineral sequestration.
基金the National Natural Science Foundation of China(Grant No:32360052)。
文摘Tufa is an important type of landscape in karst regions.In recent years,the loss of landscape diversity due to tufa dissolution is affecting the stability of local ecosystems.Therefore,determining the factors and their mechanisms involved in tufa dissolution is important for preserving regional landscape diversity and local ecosystem stability.In this study,we selected four tufa sites with different degrees of dissolution(undissolved tufa,lightly dissolved tufa,moderately dissolved tufa,and heavily dissolved tufa)in Xiangzhigou karst region of Guizhou Province as the study objects.We explored the effects of natural plant colonization on tufa dissolution using changes inαandβdiversity indices,soil physicochemical indicators,tufa components,and tufa substrate.The results indicated that the Shannon-wiener index,Simpson index and Patrick richness index gradually increased with tufa's increasing degree of dissolution.Additionally,the dissolution degree exhibited a significantly negative correlation with the species diversity(p<0.05).Natural vegetation colonization is the primary cause of changes in the proportion of tufa components and changes in the physicochemical properties of overlying tufa soils.The proportion of CaO components decreased significantly,and the proportion of loss on ignition components increased significantly.Soil organic carbon,pH,total nitrogen,available nitrogen,total phosphorus,available phosphorus,total potassium,available potassium,β-glucosidase,and urease gradually increased with deeper tufa dissolution and were negatively correlated with the degree of dissolution(p<0.05).It indicates that tufa is a process of dissolution into the soil and gradual improvement of the physicochemical properties of the overlying soil.Furthermore,scanning electron micrographs revealed the transition from dense to fragmented tufa structure under the influence of plants.In conclusion,this study found that improving plant diversity exacerbated tufa dissolution.Our findings provide a theoretical reference for the preventing and controlling of tufa dissolution in karst.
基金Science and Technology Million Project of Inner Mongolia Medical University(Grant No.YKD2014KJBW012)
文摘In the present study, we investigated the complexation of risperidone with hydroxypropyl-β-cyclodextrin （HP-β-CD） in aqueous solution due to the poor water solubility and low oral bioavailability of risperidone in humans. The effect of temperature on the complexation was examined, and thermodynamic parameters of the complexation process, such as Gibbs free energy change （AG）, enthalpy change （AH） and entropy change （AS）, were also explored. Meantime, the solid dispersion of risperidone with HP-β-CD was prepared and confirmed by Fourier IR spectroscopy and X-ray diffractometry. The experimental results suggested that the complex of the drug with HP-β-CD at a molar ratio of 1：1 could form in aqueous solution, and the complexation was an endothermic and entropy-driven process. The risperidone-HP-β-CD solid dispersion exhibited a remarkable improvement in the dissolution rate of the drug. This might be attributed to the amorphous state, the enhanced wettability as well as the complex formation of the drug with HP-β-CD in aqueous solution.
文摘AimTo study effects of PVP K30 on the aque ou s solubility and dissolution properties of daidzein. Methods To measure the aqueous solubility and dissolution rates of daidzein in three diffe rent states (within solid dispersions, physical mixtures and as a pure drug) and investigate drug-polymer interactions in the solid state using X-ray powder d iffraction and fourier-transform infrared spectroscopy. Results The negative values of the Gibbs free energy and enthalpy of transfer explaine d the spontaneous transfer of daidzein from phosphate buffer solution (PBS) to a solution of PVP in PBS. X-ray powder diffraction patterns showed that the drug was in the amorphous state (ratio of the drug ∶ PVP<1∶5) when dispers ed i n PVP K30. The infrared spectra indicated there exist interactions between the O H of daidzein and the C=O of PVP K30. Conclusionthe dispersion of daidzein in PVP K30 considerably enhances the solubility and dissolution rat e.
基金funds from the National Natural Science Foundation of China(51772082 and 51804106)the Natural Science Foundation of Hunan Province(2023JJ10005)
文摘Manganese-based material is a prospective cathode material for aqueous zinc ion batteries(ZIBs)by virtue of its high theoretical capacity,high operating voltage,and low price.However,the manganese dissolution during the electrochemical reaction causes its electrochemical cycling stability to be undesirable.In this work,heterointerface engineering-induced oxygen defects are introduced into heterostructure MnO_(2)(δa-MnO_(2))by in situ electrochemical activation to inhibit manganese dissolution for aqueous zinc ion batteries.Meanwhile,the heterointerface between the disordered amorphous and the crystalline MnO_(2)ofδa-MnO_(2)is decisive for the formation of oxygen defects.And the experimental results indicate that the manganese dissolution ofδa-MnO_(2)is considerably inhibited during the charge/discharge cycle.Theoretical analysis indicates that the oxygen defect regulates the electronic and band structure and the Mn-O bonding state of the electrode material,thereby promoting electron transport kinetics as well as inhibiting Mn dissolution.Consequently,the capacity ofδa-MnO_(2)does not degrade after 100 cycles at a current density of 0.5 Ag^(-1)and also 91%capacity retention after 500cycles at 1 Ag^(-1).This study provides a promising insight into the development of high-performance manganese-based cathode materials through a facile and low-cost strategy.
基金Supported by the National Natural Science Foundation of China(42202176)CNPC-Southwest University of Petroleum Innovation Consortium Cooperation Project(2020CX050103).
文摘To clarify the formation and distribution of feldspar dissolution pores and predict the distribution of high-quality reservoir in gravity flow sandstone of the 7^(th) member of Triassic Yanchang Formation(Chang 7 Member)in the Ordos Basin,thin sections,scanning electron microscopy,energy spectrum analysis,X-ray diffraction whole rock analysis,and dissolution experiments are employed in this study to investigate the characteristics and control factors of feldspar dissolution pores.The results show that:(1)Three types of diagenetic processes are observed in the feldspar of Chang 7 sandstone in the study area:secondary overgrowth of feldspar,replacement by clay and calcite,and dissolution of detrital feldspar.(2)The feldspar dissolution of Chang 7 tight sandstone is caused by organic acid,and is further affected by the type of feldspar,the degree of early feldspar alteration,and the buffering effect of mica debris on organic acid.(3)Feldspars have varying degrees of dissolution.Potassium feldspar is more susceptible to dissolution than plagioclase.Among potassium feldspar,orthoclase is more soluble than microcline,and unaltered feldspar is more soluble than early kaolinized or sericitized feldspar.(4)The dissolution experiment demonstrated that the presence of mica can hinder the dissolution of feldspar.Mica of the same mass has a significantly stronger capacity to consume organic acids than feldspar.(5)Dissolution pores in feldspar of Chang 7 Member are more abundant in areas with low mica content,and they improve the reservoir physical properties,while in areas with high mica content,the number of feldspar dissolution pores decreases significantly.
