Sugars are widely recognized for their ability to stabilize cell membranes during dehydration.However,the precise mechanisms by which sugars interact with lipid bilayers remain unclear.This mini-review synthesizes fou...Sugars are widely recognized for their ability to stabilize cell membranes during dehydration.However,the precise mechanisms by which sugars interact with lipid bilayers remain unclear.This mini-review synthesizes four key hypotheses explaining sugar-mediated protection of dehydrated bilayers:the Water Replacement Hypothesis(WRH),Hydration Force Hypothesis(HFH),Headgroup Bridging Hypothesis(HBH),and Vitrification Hypothesis(VH).We argue that these mechanisms are not mutually exclusive but instead operate synergistically under different cellular contexts.We propose that these hypotheses are not mutually exclusive but likely operate under different cellular contexts.Future studies should prioritize the development of biologically realistic membrane models-incorporating diverse lipids,proteins,and asymmetric leaflets-to elucidate the exact roles and mechanisms of sugars in membrane stabilization.Such advancements will enhance our understanding of anhydrobiosis and inform cryopreservation strategies for mammalian cells.展开更多
Fly ash （FA） and ground granulated blast-furnace slag （GGBFS） were added to improve the performances of regenerated binding materials （RBM） which refer to dehydrated phases with rebinding ability of waste harden...Fly ash （FA） and ground granulated blast-furnace slag （GGBFS） were added to improve the performances of regenerated binding materials （RBM） which refer to dehydrated phases with rebinding ability of waste hardened cement paste. Flowability tests, compressive strength tests, SEM, TG-DSC, and non-evaporable water content tests were employed to study the performances of the combined binding materials and the interactions between RBM, FA, and GGBFS. Results show that adding FA or GGBFS can improve the workability of RBM paste, and GGBFS has positive effects on strength of RBM. Pozzolanic reactions happen between RBM, FA, and GGBFS. And the activation effect of RBM to FA and GGBFS is superior to that of P.O grade-32.5 cement, especially at earlier ages, because of the high reactive f-CaO existing in RBM. On the advantages of the synergetic effects of RBM and pozzolanic admixtures such as FA and GGBFS, new combined binding materials can be prepared by blending them together.展开更多
Taking the saline lake bischofite and NH4Cl that was removed with the ammonia method and continuously followed by filtration as raw materials with a molar ratio of 1∶1 of MgCl2 to NH4Cl, ammonium carnallite was synth...Taking the saline lake bischofite and NH4Cl that was removed with the ammonia method and continuously followed by filtration as raw materials with a molar ratio of 1∶1 of MgCl2 to NH4Cl, ammonium carnallite was synthesized. And then the ammonium carnallite was dehydrated to some extent at 160℃ for 4 h. Ammonium carnallite reacted with ammonia at 240℃ for 150 min and the ammonation ammonium carnallite was produced. Finally, the ammonation ammonium carnallite was calcined at 750℃ into anhydrous magnesium chloride containing only 0.1%（mass fraction） of MgO. On the other hand, dehydrated ammonium carnallite was mixed with the solid ammonium chloride at mass ratio 1∶4 at high temperature and with the differential pressure of NH3 above 30.5kPa. The dehydrated ammonium carnallite of mixture was dehydrated at 410℃, and then calcined at 700℃ into anhydrous magnesium chloride with only 0.087%（mass fraction） of MgO. X-ray diffraction and electron microscopy analysis results prove that anhydrous magnesium chloride obtained by both methods hasn’t mixed phases, the particle is large and even has good dispersion, which is suitable for preparation of metal magnesium in the electrolysis.展开更多
To solve the disposal problems of solid wastes, dehydrated sewage sludge and Yellow River sediments were tested as components for production of ultra-lightweight ceramsite. The effects of Yellow River sediments additi...To solve the disposal problems of solid wastes, dehydrated sewage sludge and Yellow River sediments were tested as components for production of ultra-lightweight ceramsite. The effects of Yellow River sediments addition on the characteristics of ceramsite were investigated. Ceramsite with different Yellow River sediments additions was characterized using thermal analysis, X-ray diffraction, morphological structures analyses, pore size distributions and porosity analyses. Chemical components, especially ratios of Si O2 ＋ Al2O3/Flux, were used to explain the glassy shell formation, physical properties and pores distribution of ultralightweight ceramsite; physical forces for instance expansion force and frictional resistance which combined with Si O2 ＋ Al2O3/Flux ratios were used to explain the bloating mechanism. Results showed that the maximum addition of Yellow River sediments for making ultra-lightweight ceramsite was 35%. Macropores（between 0.226 μm and 0.554 μm） of ultra-lightweight ceramsite were dominant in the pore structures of ultra-lightweight ceramsite and its porosity was up to 67.7%. Physical force of expansion force was constant with the variation of Yellow River sediments content and physical force of frictional resistance was decreased with the increase of Yellow River sediments addition. The relationship between expansion and frictional resistance could determine the expansion rate of ceramsite. Larger pores inside the ceramsite bodies could be obtained as Yellow River sediments additions ranged from 10% to 30%. Ceramsite with higher Yellow River sediments additions of 40%（Si O2 ＋ Al2O3/Flux ratios 4.25） became denser and have lower porosity. Crystal components analysis proved that the sintering process made some components of raw materials transfer into other crystals having better thermostability.展开更多
Using geotextile bag dehydrated soil to construct dikes for land reclamation to substitute conventional straw bags is an urgent need in Tianjin New Harbor, China. This paper introduces the method to build a dike for h...Using geotextile bag dehydrated soil to construct dikes for land reclamation to substitute conventional straw bags is an urgent need in Tianjin New Harbor, China. This paper introduces the method to build a dike for hydraulic filling. The soil for filling the geotextile bags was tested in wave trench; the stress developed during construction was calculated by establishing a numerical model and compared with the tensile strength of the geotextile; the stability and settlement of the dike were estimated by performing centrifuge tests. Through this study, the following information was obtained: 1) The cohesionless silt with plasticity index less than 10 is suitable for filling the geotextile bags. The geotextile bag dehydrated soil consolidated very quickly even under the action of wave force. 2) A numerical model was devised to find the limit injection height and to calculate the tensile stress developed in the geotextile bags when they were piled up to form the dike. The calculated stress was compared with the strength of the geotextile, showing that the design is reasonably safe. 3) Centrifuge test results show that the designed dike will be stable and the settlement of dike will be less than the design requirement.展开更多
We experimentally studied the interaction between pozzolanic material（fly ash） and dehydrated autoclaved aerated concrete（DAAC）. The DAAC powder was obtained by grinding aerated concrete waste to particles fi ner ...We experimentally studied the interaction between pozzolanic material（fly ash） and dehydrated autoclaved aerated concrete（DAAC）. The DAAC powder was obtained by grinding aerated concrete waste to particles fi ner than 75μm and was then heated to temperatures up to 900 ℃. New cementitious material was prepared by proportioning fly ash and DAAC, named as AF. X-ray diffraction（XRD） was employed to identify the crystalline phases of DAAC before and after rehydration. The hydration process of AF was analyzed by the heat of hydration and non-evaporable water content（Wn）. The experimental results show that the highest reactivity of DAAC can be obtained by calcining the powder at 700 ℃ and the dehydrated products are mainly β-C2 S and CaO. The cumulative heat of hydration and Wn was found to be strongly dependent on the replacement level of fl y ash, increasing the replacement level of fl y ash lowered them in AF. The strength contribution rates on pozzolanic effect of fl y ash in AF are always negative, showing a contrary tendency of that of cement-fl y ash system.展开更多
Physicochemical, functional and digestibility analyses were done of dehydrated quail egg white to determine its possible practical applications. Quail egg white was dehydrated by air convection using one of two temper...Physicochemical, functional and digestibility analyses were done of dehydrated quail egg white to determine its possible practical applications. Quail egg white was dehydrated by air convection using one of two temperatures and times: M1 (65℃, 3.5 h), M2 (65℃, 5.0 h), M3 (70℃, 3.5 h) and M4 (70℃, 5.0 h). Lyophilized quail egg white was used as a standard. All four air-dried treatments had good protein levels (92.56% to 93.96%), with electrophoresis showing the predominant proteins to be lysozyme, ovalbumin and ovotransferin. Denaturation temperatures ranged from 81.16℃ to 83.85℃ and denaturation enthalpy values from 5.51 to 9.08 J/g. Treatments M1-4 had lower water-holding (0.90 - 2.95 g/g) and oil-holding (0.92 - 1.01 g/g) capacities than the lyophilized treatment (4.5 g/g, 1.95 g/g, respectively). Foaming capacity was pH-dependent in all five treatments, with the lowest values at alkaline pH and the highest (153% to 222%) at acid pH (pH 2). Foam stability was lowest at acid pH and highest at alkaline pH. Emulsifying activity in the air-dried treatments was highest at pH 8 (41% - 46%). Emulsion stability was pH-dependent and highest in M3 between pH 2 and 4 (96.16% to 95.74%, respectively). In the air-dried treatments, in vitro protein digestibility was as high as 83.02% (M3).展开更多
Eased on four constant parameters (the site energy differences E-M2-E-M1 = 25.50 kJ/mol, E-M3-E-M1 = -10.73 kJ/mol and the potential energies of interactions between the cation pairs occupying adjacent sites W-12 = 45...Eased on four constant parameters (the site energy differences E-M2-E-M1 = 25.50 kJ/mol, E-M3-E-M1 = -10.73 kJ/mol and the potential energies of interactions between the cation pairs occupying adjacent sites W-12 = 45.60 kJ/mol W-14 = 0.56 kJ/mol) and a temperature-dependent parameter E-M4-E-M1 = 2.68(T/323)(2.5) kJ/mol, the equilibrium distributions of the exchangeable cations, K-s(+,), over those four available cation sites in K22.4Al22.4Si73.6O192 are studied by the simulated annealing method.展开更多
BACKGROUND Patients affected by cystic fibrosis can present with metabolic alkalosis such as Bartter's syndrome.In this case report we want to underline this differential diagnosis and we aimed focusing on the sus...BACKGROUND Patients affected by cystic fibrosis can present with metabolic alkalosis such as Bartter's syndrome.In this case report we want to underline this differential diagnosis and we aimed focusing on the suspect of cystic fibrosis,also in case of a negative newborn screening.CASE SUMMARY In a hot August–with a mean environmental temperature of 36℃–an 8-mo-old female patient presented with severe dehydration complicated by hypokalemic metabolic alkalosis,in absence of fever,diarrhea and vomiting.Differential diagnosis between cystic fibrosis and tubulopathies causing metabolic alkalosis(Bartter's Syndrome)was considered.We started intravenous rehydration with subsequent improvement of clinical conditions and serum electrolytes normalization.We diagnosed a mild form of cystic fibrosis(heterozygous mutations:G126 D and F508 del in the cystic fibrosis transmembrane conductance regulator gene).The trigger factor of this condition had been heat exposure.CONCLUSION When facing a patient with hypokalemic metabolic alkalosis,cystic fibrosis presenting with Pseudo-Bartter's syndrome should be considered in the differential diagnosis,even if the newborn screening was negative.展开更多
AIM:To describe the design and clinical application of a corneal donor dehydrator which can quickly dehydrate corneas and keep its original shape.METHODS:The corneal donor material is placed on stainless steel beads w...AIM:To describe the design and clinical application of a corneal donor dehydrator which can quickly dehydrate corneas and keep its original shape.METHODS:The corneal donor material is placed on stainless steel beads with different diameters in the dehydrating box to make the cornea the same shape as the steel ball.Then,the cornea is placed inside the dehydrater for rapid dehydrating using the internal cleaning and ventilation system.Totally 83 eyes underwent deep anterior lamellar keratoplasty(DALK)using corneal donor tissue preserved with corneal dehydrater,and 60 patients(60 eyes)received DALK by the same surgeon using corneal donor tissue preserved with glycerol were included in the control group.The best corrected visual acuity(BCVA),the thickness and transparency of the corneal buttons were recorded.RESULTS:After the completion of dehydrating,all the donor corneas maintained a normal shape without any shrinkage or distortion,and the average intraoperative rehydration time was 43.3±12.1 s during operation.The mean BCVA of the dehydrater group was 0.30±0.18 at 1 wk and 0.32±0.16 at 1 mo,which were statistically better than that of the control group(P<0.001).The score of corneal buttons transparency were lower than that of the control group with statistical difference(P<0.001).The thickness of corneal buttons at 1 wk and at 1 mo in the dehydrater group was significantly better than that of the control group respectively(P<0.001).One week after operation,no corneal button turbidity or edema was observed in both groups.CONCLUSION:The dehydrater can quickly dehydrate the corneal material in a clean and airtight environment and maintain the original shape of the corneal donor during the dehydrating process.This dehydrater is recommended for long-term high-quality preservation in areas where corneal materials cannot be used within a reasonable time period.展开更多
The design and development of high-performance anodes pose significant challenges in the construction of next-generation rechargeable lithium-ion batteries(LIBs).Sodium molybdate dihydrate(Na_(2)MoO_(4)·2H_(2)O)h...The design and development of high-performance anodes pose significant challenges in the construction of next-generation rechargeable lithium-ion batteries(LIBs).Sodium molybdate dihydrate(Na_(2)MoO_(4)·2H_(2)O)has garnered increasing attention due to its cost-effectiveness,non-toxicity and earth abundance.To enhance the Li storage performance of Na_(2)MoO_(4)·2H_(2)O,a crystallographic orientation regulation strategy is proposed in this work.Initially,density functional theory calculations are carried out to demonstrate that the(020)crystal plane of Na_(2)MoO_(4)·2H_(2)O offers the lowest energy barrier for Li^(+)migration.Subsequently,the preferred crystallographic orientation of Na_(2)MoO_(4)·2H_(2)O crystal is tuned through a low-temperature recrystallization method.Furthermore,the microstructure and phase changes of Na_(2)MoO_(4)·2H_(2)O during the lithiation/de-lithiation process are studied using in situ and ex situ XRD tests,ex situ XPS and cyclic voltammetry to unravel its Li^(+)storage mechanism.Upon application as LIBs anode,the Na_(2)MoO_(4)·2H_(2)O single-crystal particles with a preferred(020)surface exhibit superior reversible capacity,high-capacity retention and high cycling stability.The enhanced Li storage performance should be attributed to the regulated crystallographic orientation and small changes in the crystal microstructure during the charge/discharge process,which facilitates Li^(+)migration and bolsters structural stability.Notably,this study introduces a novel concept and a simple synthesis method for the advancement of electrodes in rechargeable batteries.展开更多
Layered double hydroxides （LDHs） are a materials with extensive applications and class of two-dimensional （2D） layered well-developed synthesizing methods in aqueous media. In this work, we introduce an alcohother...Layered double hydroxides （LDHs） are a materials with extensive applications and class of two-dimensional （2D） layered well-developed synthesizing methods in aqueous media. In this work, we introduce an alcohothermal synthesis method for fabricating NiFe-LDHs with dehydrated galleries. The proposed process involves incomplete hydrolysis of urea for the simultaneous precipitation of metal ions, with the resulting water-deficient ethanol environment leading to the formation of a dehydrated structure. The formation of a gallery-dehydrated layer structure was confirmed by X-ray diffraction （XRD）, as well as by a subsequent rehydration process. The methodology introduced here is also applicable for fabricating Fe-based LDHs （NiFe-LDH and NiCoFe-LDH） nanoarrays, which cannot be produced under the same conditions in aqueous media because of the different precipitation processes involved. The LDH nanoarrays exhibit excellent electrocatalytic performance in the oxygen evolution reaction, as a result of their high intrinsic activity and unique structural features. In summary, this study not only introduces a new method for synthesizing LDH materials, but also provides a new route towards highly active and robust electrodes for electrocatalvsis.展开更多
The petrogenesis and genetic link to polymetallic mineralization of the granites in the Dayishan complex,southern Hunan province remain debated.Here,we present an integrated study on the petrology,zircon U-Pb ages and...The petrogenesis and genetic link to polymetallic mineralization of the granites in the Dayishan complex,southern Hunan province remain debated.Here,we present an integrated study on the petrology,zircon U-Pb ages and whole-rock geochemistry for this complex.Our findings indicate that the southern complex consists of(amphibole-bearing)biotite granites and muscovite granites emplaced at 153-151 Ma,and the central and northern complex consists of two-mica granites and tourmaline-bearing muscovite granites,respectively with the former emplaced at 164 Ma and the latter at 150 Ma.The(amphibole-bearing)biotite granites have SiO_(2) contents of 68.0-73.8 wt% and are enriched in alkalis and rare earth elements and depleted in Sr and Ba.They display Zr+Y+Ce+Nb>350 ppm and 10000×Ga/Al>2.6 along with high zircon saturation temperatures(821-883oC).The two-mica granites and(tourmaline-bearing)muscovite granites have high SiO_(2)(74.4-77.3 wt%)and low Ga/Al,Zr+Nb+Ce+Y,K/Rb,Zr/Hf,and Nb/Ta along with low zircon saturation temperatures(709-817℃).Geochemical characteristics suggest that the(amphibole-bearing)biotite granites are A-type granites generated through shallow dehydration melting of early Paleozoic granitoids,and that the two-mica granites and(tourmaline-bearing)muscovite granites are fractionated A-type granites produced through fractionation crystallization from the(amphibole-bearing)biotite granites accompanied by fluid fractionation.展开更多
The hydrothermal stability of zeolites is essential for their potential applications in biomass conversion,especially in processes involving elevated temperatures alongside the use or generation of H_(2)O.In this stud...The hydrothermal stability of zeolites is essential for their potential applications in biomass conversion,especially in processes involving elevated temperatures alongside the use or generation of H_(2)O.In this study,we employed F-ions as mineralizers to synthesize hydrothermally stable ZSM-5 zeolites under acidic conditions.The acidic synthesis system promotes zeolites with fewer silanol-terminated lattice defects(ZSM-5(A))compared to the traditional basic conditions(ZSM-5(B)),endowing materials with substantially higher structural integrity and hydrophobicity.After 10 days of autoclave treatment at 200℃ in aqueous phase,H-ZSM-5(A)demonstrated nearly unchanged reaction rates in the dehydration of cyclohexanol,while H-ZSM-5(B)lost>50%of the dehydration activity.Additionally,H-ZSM-5(A)delivered higher initial dehydration rates compared to H-ZSM-5(B).The different measured activation energies further revealed variations in reaction pathways during cyclohexanol dehydration,i.e.,the monomer-or dimer-mediated routes depending on the concentration of alcohol molecule within zeolite pores,providing additional evidence for the strengthened hydrophobic nature of H-ZSM-5(A).Beyond this,the zeolite surface properties and the strength of cyclohexanol-zeolite interactions may impose additional transport/adsorption barriers attributed to multi-phase phenomena on the more polar H-ZSM-5(B)zeolite surfaces.More importantly,the hydrothermal treatment did not induce significant desilication and dealumination in H-ZSM-5(A),thereby preserving its active acid sites and ensuring exceptional hydrothermal stability.The present work fundamentally studies the synthesis of hydrothermally stable zeolites in an acidic medium using fluorides and expands the understanding of polar interactions in catalysis,characterized by the dehydration of cyclohexanol,for future application in biomass conversion.展开更多
It is highly attractive for the catalysts prepared from renewable materials and/or industrial by-products.Herein,lignosulfonate(LS)as the by-product in the papermaking industry was utilized to fabricate Sn-containing ...It is highly attractive for the catalysts prepared from renewable materials and/or industrial by-products.Herein,lignosulfonate(LS)as the by-product in the papermaking industry was utilized to fabricate Sn-containing organic-inorganic complexing catalysts(Sn(x)@LS)by a simple hydrothermal self-assembly process.The fabricated Sn(x)@LS played an excellent performance in the dehydration of xylose into furfural in the carbon tetrachloride(CTC)-water biphasic system,yielding 78.5%furfural at 180℃for 60 min.It was revealed that strong coordination between Sn4+and the phenolic hydroxyl groups of LS created a robust organic-inorganic skeleton(-Ar-O-Sn-O-Ar-),simultaneously generating potent Lewis acidic sites,and sulfonic acid groups of LS acted as Bronsted acidic sites.Gromacs simulations verified that CTC did not form hydrogen bonds with xylose,which may reduce xylose consumption.The CTC phase effectively extracted furfural,thereby preventing its side reactions throughout the entire process.In addition,Sn(x)@LS exhibited excellent cyclic stability in at least five reaction cycles with only a 5.0% decrease in furfural yield.Thus,this work will give a new window for the catalysts prepared from LS as the industrial by-products in the production of platform chemicals,which is a sustainable chemical conversion process.展开更多
Re-crosslinkable preformed particle gel(RPPG)has been considered to be one of the most promising gels for dealing with fracture and void space conduit(VSC)conformance problems.However,the dehydration of RPPG during it...Re-crosslinkable preformed particle gel(RPPG)has been considered to be one of the most promising gels for dealing with fracture and void space conduit(VSC)conformance problems.However,the dehydration of RPPG during its propagation in the fracture-type features and its effect on gel properties remains unclear.This paper investigates the dehydration behavior during RPPG propagating in an open fracture using matrix-free fracture model.Then the results were verified using real fractured sandstone core model.Moreover,the gel properties after extruding a fracture were studied in detail including gel dehydration and gel strength.Results reveal that the RPPG properties changed significantly with increasing propagation distance,which correlated with the gel injection rate.At high gel injection rates,the dehydration and gel strength(Gʹ)decrease with increasing propagation distance.In contrast,the opposite result was found at low injection rates.Based on the study of the different gel injection rates,it is found that dehydration time is another key factor affecting dehydration behavior.Results also indicate that the fracture width affects gel dehydration at different locations.Dehydration was more pronounced at narrow fractures but only in the inlet section,while in the outlet section,RPPG contains more water than the initial condition.This study has profound implications for field applications.It provides new insights into the transport of RPPG in fractures and helps field engineers to optimize the gel injection operations.展开更多
The hard-to-remove lattice water has been regarded as a significant obstacle impeding the practical use of Prussian blue analogue cathodes for sodium-ion batteries.This work monitored the electrochemical evolution of ...The hard-to-remove lattice water has been regarded as a significant obstacle impeding the practical use of Prussian blue analogue cathodes for sodium-ion batteries.This work monitored the electrochemical evolution of a hydrated monoclinic sodium manganese hexacyanoferrate cathode by solid-state nuclear magnetic resonance(NMR).For the first time,we established a correlation between the chemical shifts of ^(23)Na NMR signals and the presence or absence of lattice water within this cathode.Through this method,we verified the electrochemical dehydration process that coincides with the merging of two redox platforms and a phase transformation in the initial cycles.Furthermore,we discovered that the lattice water is completely removed after several-day cell rest following a single activation cycle.展开更多
The dependence of the subduction regime on three-dimensional slab geometry poses a challenge for accurately estimating the evolving thermal structure of megathrusts globally. Although slab dips and ages have gained at...The dependence of the subduction regime on three-dimensional slab geometry poses a challenge for accurately estimating the evolving thermal structure of megathrusts globally. Although slab dips and ages have gained attention, the specific impacts of oblique subduction remain unmeasured. Here, we present an integrated thermal model that quantifies how slab morphology can shape the thermal state of megathrusts, such as those in the Makran Subduction Zone. The model considers both slab obliquity and depth variations along the trench. We find a considerable match between the slab petrological dehydration zone and the distribution of great crustal earthquakes. We suggest that the accumulation of fluids along megathrusts by slab metamorphism can foster more polarized conditions for decreasing plate coupling and increasing interplate ruptures. It is thus imperative to improve model representation and more realistically represent how drivers of slab geometry affect metamorphic transitions and the occurrence of earthquakes at megathrusts.展开更多
Multiple active components in steel slags can optimize soil texture and catalyze the thermal desorption of refractory organic pollutants,especially polycyclic aromatic hydrocarbons(PAHs).In this study,a safety and ris...Multiple active components in steel slags can optimize soil texture and catalyze the thermal desorption of refractory organic pollutants,especially polycyclic aromatic hydrocarbons(PAHs).In this study,a safety and risk assessment was conducted on toxic metals present in collected steel slags,and the refining slag with a high content of free-CaO from the XG iron and steel plant(XGRS)was selected and used to regulate the plasticity index(PI)of clay soils.For the clay soil with high liquid limit and high plasticity(CH),the PI reduced from 34.3%to 24.8%with steel slags at an addition ratio of 10%(mass percent),and for the clay soil with low liquid limit(CL),the PI decreased from 22.8%to 16.5%,resulting in silt soil with optimal thermal properties.The thermal removal efficiency of PAHs in CH decreased from 81.9%to 74.0%at 350℃ as the soil water content increased from 0 to 150 g kg^(-1),due to the hydration and swelling of clay minerals and the heat loss associated with dehydroxylation and dehydration.The efficiency further decreased to 68.7%using 2%(mass percent)CaO as an additive due to the delayed dehydr(oxyl)ation of clay minerals and enhanced aromatization of soil organic matter.In contrast,addition of 2%high-content titania-bearing slag(HTBS)enhanced the removal efficiency of high-ring PAHs,with the efficiency increasing for 5-ring from 52.6%to 59.7%and for 6-ring from 76.6%to 81.8%.This is due to the presence of amorphous TiO_(2) and crystalline CaTiO_(3) in HTBS,which can degrade water to produce reactive oxygen species.The 2%XGRS addition facilitated the complete removal of PAHs by air-supplemented lattice oxygen,leading to the oxidation of C–C bonds in CH to C–O,C=O,and O–C=O functional groups.This study provides valuable insights into the use of additives to enhance the thermal remediation of PAH-contaminated clay soils via activating oxygen species and oxidizing C–C bonds in organo-mineral complexes within clay soils.展开更多
Although soil exhibits excellent mechanical performance,the microstructural changes of biopolymer within soil due to dehydration and rehydration are rarely explored.This study aims to explore xanthan gum soil microstr...Although soil exhibits excellent mechanical performance,the microstructural changes of biopolymer within soil due to dehydration and rehydration are rarely explored.This study aims to explore xanthan gum soil microstructure and strength behavior under different dehydration and rehydration degrees using nuclear magnetic resonance(NMR)and unconfined compressive strength tests.The results showed that the proportion of large-volume biopolymer gel within the sample decreased from 91.91%to 38.28%during dehydration,but increased to 90.44%upon rehydration when sample moisture returned to its original level.The NMR images revealed that biopolymer gel evaporated from outside during the dehydration process,causing the dehydrated biopolymer to shrink and form a high-strength glass,which directly enhanced the soil's macroscopic mechanical properties.Upon rehydration,the biopolymer reabsorbed moisture and gradually expanded,leading to weakened connections between soil particles and a decrease in strength.Therefore,even when the moisture content of soil remained constant during the dehydration and rehydration processes,their unconfined compressive strength(UCS)and failure patterns exhibited significant differences.Both the UCS and NMR signal of biopolymer-treated soil decreased after the first dehydration and rehydration cycle,stabilizing gradually after subsequent cycles.展开更多
基金supported by the National Natural Science Foundation of China,China(Grant No.52376052)the Anhui Provincial Natural Science Foundation,China(Grant No.2308085ME174).
文摘Sugars are widely recognized for their ability to stabilize cell membranes during dehydration.However,the precise mechanisms by which sugars interact with lipid bilayers remain unclear.This mini-review synthesizes four key hypotheses explaining sugar-mediated protection of dehydrated bilayers:the Water Replacement Hypothesis(WRH),Hydration Force Hypothesis(HFH),Headgroup Bridging Hypothesis(HBH),and Vitrification Hypothesis(VH).We argue that these mechanisms are not mutually exclusive but instead operate synergistically under different cellular contexts.We propose that these hypotheses are not mutually exclusive but likely operate under different cellular contexts.Future studies should prioritize the development of biologically realistic membrane models-incorporating diverse lipids,proteins,and asymmetric leaflets-to elucidate the exact roles and mechanisms of sugars in membrane stabilization.Such advancements will enhance our understanding of anhydrobiosis and inform cryopreservation strategies for mammalian cells.
基金Funded by the National Science Foundation of China(No. 50508034)
文摘Fly ash （FA） and ground granulated blast-furnace slag （GGBFS） were added to improve the performances of regenerated binding materials （RBM） which refer to dehydrated phases with rebinding ability of waste hardened cement paste. Flowability tests, compressive strength tests, SEM, TG-DSC, and non-evaporable water content tests were employed to study the performances of the combined binding materials and the interactions between RBM, FA, and GGBFS. Results show that adding FA or GGBFS can improve the workability of RBM paste, and GGBFS has positive effects on strength of RBM. Pozzolanic reactions happen between RBM, FA, and GGBFS. And the activation effect of RBM to FA and GGBFS is superior to that of P.O grade-32.5 cement, especially at earlier ages, because of the high reactive f-CaO existing in RBM. On the advantages of the synergetic effects of RBM and pozzolanic admixtures such as FA and GGBFS, new combined binding materials can be prepared by blending them together.
基金Project(2000 G 101) supported by the Key Science and Technology Research Project of Qinghai Province
文摘Taking the saline lake bischofite and NH4Cl that was removed with the ammonia method and continuously followed by filtration as raw materials with a molar ratio of 1∶1 of MgCl2 to NH4Cl, ammonium carnallite was synthesized. And then the ammonium carnallite was dehydrated to some extent at 160℃ for 4 h. Ammonium carnallite reacted with ammonia at 240℃ for 150 min and the ammonation ammonium carnallite was produced. Finally, the ammonation ammonium carnallite was calcined at 750℃ into anhydrous magnesium chloride containing only 0.1%（mass fraction） of MgO. On the other hand, dehydrated ammonium carnallite was mixed with the solid ammonium chloride at mass ratio 1∶4 at high temperature and with the differential pressure of NH3 above 30.5kPa. The dehydrated ammonium carnallite of mixture was dehydrated at 410℃, and then calcined at 700℃ into anhydrous magnesium chloride with only 0.087%（mass fraction） of MgO. X-ray diffraction and electron microscopy analysis results prove that anhydrous magnesium chloride obtained by both methods hasn’t mixed phases, the particle is large and even has good dispersion, which is suitable for preparation of metal magnesium in the electrolysis.
基金Funded by the Doctoral Program of Higher Education of China(No.20100131110005)
文摘To solve the disposal problems of solid wastes, dehydrated sewage sludge and Yellow River sediments were tested as components for production of ultra-lightweight ceramsite. The effects of Yellow River sediments addition on the characteristics of ceramsite were investigated. Ceramsite with different Yellow River sediments additions was characterized using thermal analysis, X-ray diffraction, morphological structures analyses, pore size distributions and porosity analyses. Chemical components, especially ratios of Si O2 ＋ Al2O3/Flux, were used to explain the glassy shell formation, physical properties and pores distribution of ultralightweight ceramsite; physical forces for instance expansion force and frictional resistance which combined with Si O2 ＋ Al2O3/Flux ratios were used to explain the bloating mechanism. Results showed that the maximum addition of Yellow River sediments for making ultra-lightweight ceramsite was 35%. Macropores（between 0.226 μm and 0.554 μm） of ultra-lightweight ceramsite were dominant in the pore structures of ultra-lightweight ceramsite and its porosity was up to 67.7%. Physical force of expansion force was constant with the variation of Yellow River sediments content and physical force of frictional resistance was decreased with the increase of Yellow River sediments addition. The relationship between expansion and frictional resistance could determine the expansion rate of ceramsite. Larger pores inside the ceramsite bodies could be obtained as Yellow River sediments additions ranged from 10% to 30%. Ceramsite with higher Yellow River sediments additions of 40%（Si O2 ＋ Al2O3/Flux ratios 4.25） became denser and have lower porosity. Crystal components analysis proved that the sintering process made some components of raw materials transfer into other crystals having better thermostability.
文摘Using geotextile bag dehydrated soil to construct dikes for land reclamation to substitute conventional straw bags is an urgent need in Tianjin New Harbor, China. This paper introduces the method to build a dike for hydraulic filling. The soil for filling the geotextile bags was tested in wave trench; the stress developed during construction was calculated by establishing a numerical model and compared with the tensile strength of the geotextile; the stability and settlement of the dike were estimated by performing centrifuge tests. Through this study, the following information was obtained: 1) The cohesionless silt with plasticity index less than 10 is suitable for filling the geotextile bags. The geotextile bag dehydrated soil consolidated very quickly even under the action of wave force. 2) A numerical model was devised to find the limit injection height and to calculate the tensile stress developed in the geotextile bags when they were piled up to form the dike. The calculated stress was compared with the strength of the geotextile, showing that the design is reasonably safe. 3) Centrifuge test results show that the designed dike will be stable and the settlement of dike will be less than the design requirement.
基金Funded by the"863"National High-tech Research and Development Program of China(No.2012AA06A112)
文摘We experimentally studied the interaction between pozzolanic material（fly ash） and dehydrated autoclaved aerated concrete（DAAC）. The DAAC powder was obtained by grinding aerated concrete waste to particles fi ner than 75μm and was then heated to temperatures up to 900 ℃. New cementitious material was prepared by proportioning fly ash and DAAC, named as AF. X-ray diffraction（XRD） was employed to identify the crystalline phases of DAAC before and after rehydration. The hydration process of AF was analyzed by the heat of hydration and non-evaporable water content（Wn）. The experimental results show that the highest reactivity of DAAC can be obtained by calcining the powder at 700 ℃ and the dehydrated products are mainly β-C2 S and CaO. The cumulative heat of hydration and Wn was found to be strongly dependent on the replacement level of fl y ash, increasing the replacement level of fl y ash lowered them in AF. The strength contribution rates on pozzolanic effect of fl y ash in AF are always negative, showing a contrary tendency of that of cement-fl y ash system.
文摘Physicochemical, functional and digestibility analyses were done of dehydrated quail egg white to determine its possible practical applications. Quail egg white was dehydrated by air convection using one of two temperatures and times: M1 (65℃, 3.5 h), M2 (65℃, 5.0 h), M3 (70℃, 3.5 h) and M4 (70℃, 5.0 h). Lyophilized quail egg white was used as a standard. All four air-dried treatments had good protein levels (92.56% to 93.96%), with electrophoresis showing the predominant proteins to be lysozyme, ovalbumin and ovotransferin. Denaturation temperatures ranged from 81.16℃ to 83.85℃ and denaturation enthalpy values from 5.51 to 9.08 J/g. Treatments M1-4 had lower water-holding (0.90 - 2.95 g/g) and oil-holding (0.92 - 1.01 g/g) capacities than the lyophilized treatment (4.5 g/g, 1.95 g/g, respectively). Foaming capacity was pH-dependent in all five treatments, with the lowest values at alkaline pH and the highest (153% to 222%) at acid pH (pH 2). Foam stability was lowest at acid pH and highest at alkaline pH. Emulsifying activity in the air-dried treatments was highest at pH 8 (41% - 46%). Emulsion stability was pH-dependent and highest in M3 between pH 2 and 4 (96.16% to 95.74%, respectively). In the air-dried treatments, in vitro protein digestibility was as high as 83.02% (M3).
文摘Eased on four constant parameters (the site energy differences E-M2-E-M1 = 25.50 kJ/mol, E-M3-E-M1 = -10.73 kJ/mol and the potential energies of interactions between the cation pairs occupying adjacent sites W-12 = 45.60 kJ/mol W-14 = 0.56 kJ/mol) and a temperature-dependent parameter E-M4-E-M1 = 2.68(T/323)(2.5) kJ/mol, the equilibrium distributions of the exchangeable cations, K-s(+,), over those four available cation sites in K22.4Al22.4Si73.6O192 are studied by the simulated annealing method.
文摘BACKGROUND Patients affected by cystic fibrosis can present with metabolic alkalosis such as Bartter's syndrome.In this case report we want to underline this differential diagnosis and we aimed focusing on the suspect of cystic fibrosis,also in case of a negative newborn screening.CASE SUMMARY In a hot August–with a mean environmental temperature of 36℃–an 8-mo-old female patient presented with severe dehydration complicated by hypokalemic metabolic alkalosis,in absence of fever,diarrhea and vomiting.Differential diagnosis between cystic fibrosis and tubulopathies causing metabolic alkalosis(Bartter's Syndrome)was considered.We started intravenous rehydration with subsequent improvement of clinical conditions and serum electrolytes normalization.We diagnosed a mild form of cystic fibrosis(heterozygous mutations:G126 D and F508 del in the cystic fibrosis transmembrane conductance regulator gene).The trigger factor of this condition had been heat exposure.CONCLUSION When facing a patient with hypokalemic metabolic alkalosis,cystic fibrosis presenting with Pseudo-Bartter's syndrome should be considered in the differential diagnosis,even if the newborn screening was negative.
基金National Natural Science Foundation of China(No.81870639,No.82070923,No.81900907)Taishan Scholar Program(No.tspd20150215,No.tsqn201812150)the Academic Promotion Program of Shandong First Medical University(No.2019RC009)。
文摘AIM:To describe the design and clinical application of a corneal donor dehydrator which can quickly dehydrate corneas and keep its original shape.METHODS:The corneal donor material is placed on stainless steel beads with different diameters in the dehydrating box to make the cornea the same shape as the steel ball.Then,the cornea is placed inside the dehydrater for rapid dehydrating using the internal cleaning and ventilation system.Totally 83 eyes underwent deep anterior lamellar keratoplasty(DALK)using corneal donor tissue preserved with corneal dehydrater,and 60 patients(60 eyes)received DALK by the same surgeon using corneal donor tissue preserved with glycerol were included in the control group.The best corrected visual acuity(BCVA),the thickness and transparency of the corneal buttons were recorded.RESULTS:After the completion of dehydrating,all the donor corneas maintained a normal shape without any shrinkage or distortion,and the average intraoperative rehydration time was 43.3±12.1 s during operation.The mean BCVA of the dehydrater group was 0.30±0.18 at 1 wk and 0.32±0.16 at 1 mo,which were statistically better than that of the control group(P<0.001).The score of corneal buttons transparency were lower than that of the control group with statistical difference(P<0.001).The thickness of corneal buttons at 1 wk and at 1 mo in the dehydrater group was significantly better than that of the control group respectively(P<0.001).One week after operation,no corneal button turbidity or edema was observed in both groups.CONCLUSION:The dehydrater can quickly dehydrate the corneal material in a clean and airtight environment and maintain the original shape of the corneal donor during the dehydrating process.This dehydrater is recommended for long-term high-quality preservation in areas where corneal materials cannot be used within a reasonable time period.
基金supported by the Natural Science Foundation of Guizhou Province(No.ZK 2022-044)the Platform of Science and Technology and Talent Team Plan of Guizhou Province(No.GCC[2023]007)+1 种基金the National Science Foundation of China(Nos.52101010 and 11964006)the Fund of Natural Science Special(Special Post)Research Foundation of Guizhou University(No.2021-018).
文摘The design and development of high-performance anodes pose significant challenges in the construction of next-generation rechargeable lithium-ion batteries(LIBs).Sodium molybdate dihydrate(Na_(2)MoO_(4)·2H_(2)O)has garnered increasing attention due to its cost-effectiveness,non-toxicity and earth abundance.To enhance the Li storage performance of Na_(2)MoO_(4)·2H_(2)O,a crystallographic orientation regulation strategy is proposed in this work.Initially,density functional theory calculations are carried out to demonstrate that the(020)crystal plane of Na_(2)MoO_(4)·2H_(2)O offers the lowest energy barrier for Li^(+)migration.Subsequently,the preferred crystallographic orientation of Na_(2)MoO_(4)·2H_(2)O crystal is tuned through a low-temperature recrystallization method.Furthermore,the microstructure and phase changes of Na_(2)MoO_(4)·2H_(2)O during the lithiation/de-lithiation process are studied using in situ and ex situ XRD tests,ex situ XPS and cyclic voltammetry to unravel its Li^(+)storage mechanism.Upon application as LIBs anode,the Na_(2)MoO_(4)·2H_(2)O single-crystal particles with a preferred(020)surface exhibit superior reversible capacity,high-capacity retention and high cycling stability.The enhanced Li storage performance should be attributed to the regulated crystallographic orientation and small changes in the crystal microstructure during the charge/discharge process,which facilitates Li^(+)migration and bolsters structural stability.Notably,this study introduces a novel concept and a simple synthesis method for the advancement of electrodes in rechargeable batteries.
文摘Layered double hydroxides （LDHs） are a materials with extensive applications and class of two-dimensional （2D） layered well-developed synthesizing methods in aqueous media. In this work, we introduce an alcohothermal synthesis method for fabricating NiFe-LDHs with dehydrated galleries. The proposed process involves incomplete hydrolysis of urea for the simultaneous precipitation of metal ions, with the resulting water-deficient ethanol environment leading to the formation of a dehydrated structure. The formation of a gallery-dehydrated layer structure was confirmed by X-ray diffraction （XRD）, as well as by a subsequent rehydration process. The methodology introduced here is also applicable for fabricating Fe-based LDHs （NiFe-LDH and NiCoFe-LDH） nanoarrays, which cannot be produced under the same conditions in aqueous media because of the different precipitation processes involved. The LDH nanoarrays exhibit excellent electrocatalytic performance in the oxygen evolution reaction, as a result of their high intrinsic activity and unique structural features. In summary, this study not only introduces a new method for synthesizing LDH materials, but also provides a new route towards highly active and robust electrodes for electrocatalvsis.
基金supported financially by the National Natural Science Foundation of China(Grant Nos.41872054 and 41272083)。
文摘The petrogenesis and genetic link to polymetallic mineralization of the granites in the Dayishan complex,southern Hunan province remain debated.Here,we present an integrated study on the petrology,zircon U-Pb ages and whole-rock geochemistry for this complex.Our findings indicate that the southern complex consists of(amphibole-bearing)biotite granites and muscovite granites emplaced at 153-151 Ma,and the central and northern complex consists of two-mica granites and tourmaline-bearing muscovite granites,respectively with the former emplaced at 164 Ma and the latter at 150 Ma.The(amphibole-bearing)biotite granites have SiO_(2) contents of 68.0-73.8 wt% and are enriched in alkalis and rare earth elements and depleted in Sr and Ba.They display Zr+Y+Ce+Nb>350 ppm and 10000×Ga/Al>2.6 along with high zircon saturation temperatures(821-883oC).The two-mica granites and(tourmaline-bearing)muscovite granites have high SiO_(2)(74.4-77.3 wt%)and low Ga/Al,Zr+Nb+Ce+Y,K/Rb,Zr/Hf,and Nb/Ta along with low zircon saturation temperatures(709-817℃).Geochemical characteristics suggest that the(amphibole-bearing)biotite granites are A-type granites generated through shallow dehydration melting of early Paleozoic granitoids,and that the two-mica granites and(tourmaline-bearing)muscovite granites are fractionated A-type granites produced through fractionation crystallization from the(amphibole-bearing)biotite granites accompanied by fluid fractionation.
文摘The hydrothermal stability of zeolites is essential for their potential applications in biomass conversion,especially in processes involving elevated temperatures alongside the use or generation of H_(2)O.In this study,we employed F-ions as mineralizers to synthesize hydrothermally stable ZSM-5 zeolites under acidic conditions.The acidic synthesis system promotes zeolites with fewer silanol-terminated lattice defects(ZSM-5(A))compared to the traditional basic conditions(ZSM-5(B)),endowing materials with substantially higher structural integrity and hydrophobicity.After 10 days of autoclave treatment at 200℃ in aqueous phase,H-ZSM-5(A)demonstrated nearly unchanged reaction rates in the dehydration of cyclohexanol,while H-ZSM-5(B)lost>50%of the dehydration activity.Additionally,H-ZSM-5(A)delivered higher initial dehydration rates compared to H-ZSM-5(B).The different measured activation energies further revealed variations in reaction pathways during cyclohexanol dehydration,i.e.,the monomer-or dimer-mediated routes depending on the concentration of alcohol molecule within zeolite pores,providing additional evidence for the strengthened hydrophobic nature of H-ZSM-5(A).Beyond this,the zeolite surface properties and the strength of cyclohexanol-zeolite interactions may impose additional transport/adsorption barriers attributed to multi-phase phenomena on the more polar H-ZSM-5(B)zeolite surfaces.More importantly,the hydrothermal treatment did not induce significant desilication and dealumination in H-ZSM-5(A),thereby preserving its active acid sites and ensuring exceptional hydrothermal stability.The present work fundamentally studies the synthesis of hydrothermally stable zeolites in an acidic medium using fluorides and expands the understanding of polar interactions in catalysis,characterized by the dehydration of cyclohexanol,for future application in biomass conversion.
基金supported by theNationalNatural Science Foundation of China(No.22361132543)China Postdoctoral Science Foundation(Pre-Station)(No.2023TQ0121)State Key Laboratory of Pulp and Paper Engineering(No.2024ZD05).
文摘It is highly attractive for the catalysts prepared from renewable materials and/or industrial by-products.Herein,lignosulfonate(LS)as the by-product in the papermaking industry was utilized to fabricate Sn-containing organic-inorganic complexing catalysts(Sn(x)@LS)by a simple hydrothermal self-assembly process.The fabricated Sn(x)@LS played an excellent performance in the dehydration of xylose into furfural in the carbon tetrachloride(CTC)-water biphasic system,yielding 78.5%furfural at 180℃for 60 min.It was revealed that strong coordination between Sn4+and the phenolic hydroxyl groups of LS created a robust organic-inorganic skeleton(-Ar-O-Sn-O-Ar-),simultaneously generating potent Lewis acidic sites,and sulfonic acid groups of LS acted as Bronsted acidic sites.Gromacs simulations verified that CTC did not form hydrogen bonds with xylose,which may reduce xylose consumption.The CTC phase effectively extracted furfural,thereby preventing its side reactions throughout the entire process.In addition,Sn(x)@LS exhibited excellent cyclic stability in at least five reaction cycles with only a 5.0% decrease in furfural yield.Thus,this work will give a new window for the catalysts prepared from LS as the industrial by-products in the production of platform chemicals,which is a sustainable chemical conversion process.
文摘Re-crosslinkable preformed particle gel(RPPG)has been considered to be one of the most promising gels for dealing with fracture and void space conduit(VSC)conformance problems.However,the dehydration of RPPG during its propagation in the fracture-type features and its effect on gel properties remains unclear.This paper investigates the dehydration behavior during RPPG propagating in an open fracture using matrix-free fracture model.Then the results were verified using real fractured sandstone core model.Moreover,the gel properties after extruding a fracture were studied in detail including gel dehydration and gel strength.Results reveal that the RPPG properties changed significantly with increasing propagation distance,which correlated with the gel injection rate.At high gel injection rates,the dehydration and gel strength(Gʹ)decrease with increasing propagation distance.In contrast,the opposite result was found at low injection rates.Based on the study of the different gel injection rates,it is found that dehydration time is another key factor affecting dehydration behavior.Results also indicate that the fracture width affects gel dehydration at different locations.Dehydration was more pronounced at narrow fractures but only in the inlet section,while in the outlet section,RPPG contains more water than the initial condition.This study has profound implications for field applications.It provides new insights into the transport of RPPG in fractures and helps field engineers to optimize the gel injection operations.
基金supported by grants from the National Natural Science Foundation of China(No.22272055)Scientific and Technological Project of Henan Province(No.222102240081)+1 种基金Science and Technology Planning Project of Anyang City(No.2022C01GX023)the support from Shanghai Synchrotron Radiation Facility(BL14B)for the sXRD experiments.
文摘The hard-to-remove lattice water has been regarded as a significant obstacle impeding the practical use of Prussian blue analogue cathodes for sodium-ion batteries.This work monitored the electrochemical evolution of a hydrated monoclinic sodium manganese hexacyanoferrate cathode by solid-state nuclear magnetic resonance(NMR).For the first time,we established a correlation between the chemical shifts of ^(23)Na NMR signals and the presence or absence of lattice water within this cathode.Through this method,we verified the electrochemical dehydration process that coincides with the merging of two redox platforms and a phase transformation in the initial cycles.Furthermore,we discovered that the lattice water is completely removed after several-day cell rest following a single activation cycle.
基金benefited from the financial support of the Chinese Academy of Sciences Pioneer Hundred Talents Programthe Second Tibetan Plateau Scientific Expedition and Research Program (Grant No. 2019QZKK0708)+2 种基金the MEXT KAKENHI grant (Grant No. 21H05203)the Kobe University Strategic International Collaborative Research Grant (Type B Fostering Joint Research)the “Science of Slowto-Fast Earthquakes” project。
文摘The dependence of the subduction regime on three-dimensional slab geometry poses a challenge for accurately estimating the evolving thermal structure of megathrusts globally. Although slab dips and ages have gained attention, the specific impacts of oblique subduction remain unmeasured. Here, we present an integrated thermal model that quantifies how slab morphology can shape the thermal state of megathrusts, such as those in the Makran Subduction Zone. The model considers both slab obliquity and depth variations along the trench. We find a considerable match between the slab petrological dehydration zone and the distribution of great crustal earthquakes. We suggest that the accumulation of fluids along megathrusts by slab metamorphism can foster more polarized conditions for decreasing plate coupling and increasing interplate ruptures. It is thus imperative to improve model representation and more realistically represent how drivers of slab geometry affect metamorphic transitions and the occurrence of earthquakes at megathrusts.
基金sponsored by the National Key R&D Program of China(No.2018YFC1802101)the National Natural Science Foundation of China(No.52170149)。
文摘Multiple active components in steel slags can optimize soil texture and catalyze the thermal desorption of refractory organic pollutants,especially polycyclic aromatic hydrocarbons(PAHs).In this study,a safety and risk assessment was conducted on toxic metals present in collected steel slags,and the refining slag with a high content of free-CaO from the XG iron and steel plant(XGRS)was selected and used to regulate the plasticity index(PI)of clay soils.For the clay soil with high liquid limit and high plasticity(CH),the PI reduced from 34.3%to 24.8%with steel slags at an addition ratio of 10%(mass percent),and for the clay soil with low liquid limit(CL),the PI decreased from 22.8%to 16.5%,resulting in silt soil with optimal thermal properties.The thermal removal efficiency of PAHs in CH decreased from 81.9%to 74.0%at 350℃ as the soil water content increased from 0 to 150 g kg^(-1),due to the hydration and swelling of clay minerals and the heat loss associated with dehydroxylation and dehydration.The efficiency further decreased to 68.7%using 2%(mass percent)CaO as an additive due to the delayed dehydr(oxyl)ation of clay minerals and enhanced aromatization of soil organic matter.In contrast,addition of 2%high-content titania-bearing slag(HTBS)enhanced the removal efficiency of high-ring PAHs,with the efficiency increasing for 5-ring from 52.6%to 59.7%and for 6-ring from 76.6%to 81.8%.This is due to the presence of amorphous TiO_(2) and crystalline CaTiO_(3) in HTBS,which can degrade water to produce reactive oxygen species.The 2%XGRS addition facilitated the complete removal of PAHs by air-supplemented lattice oxygen,leading to the oxidation of C–C bonds in CH to C–O,C=O,and O–C=O functional groups.This study provides valuable insights into the use of additives to enhance the thermal remediation of PAH-contaminated clay soils via activating oxygen species and oxidizing C–C bonds in organo-mineral complexes within clay soils.
基金supported by the National Natural Science Foundation of China(Grant No.42102324)the Natural Science Foundation of Hubei Province of China(Grant No.2024AFB686)Open Fund of Badong National Observation and Research Station of Geohazards(Grant No.BNORSG-202102).
文摘Although soil exhibits excellent mechanical performance,the microstructural changes of biopolymer within soil due to dehydration and rehydration are rarely explored.This study aims to explore xanthan gum soil microstructure and strength behavior under different dehydration and rehydration degrees using nuclear magnetic resonance(NMR)and unconfined compressive strength tests.The results showed that the proportion of large-volume biopolymer gel within the sample decreased from 91.91%to 38.28%during dehydration,but increased to 90.44%upon rehydration when sample moisture returned to its original level.The NMR images revealed that biopolymer gel evaporated from outside during the dehydration process,causing the dehydrated biopolymer to shrink and form a high-strength glass,which directly enhanced the soil's macroscopic mechanical properties.Upon rehydration,the biopolymer reabsorbed moisture and gradually expanded,leading to weakened connections between soil particles and a decrease in strength.Therefore,even when the moisture content of soil remained constant during the dehydration and rehydration processes,their unconfined compressive strength(UCS)and failure patterns exhibited significant differences.Both the UCS and NMR signal of biopolymer-treated soil decreased after the first dehydration and rehydration cycle,stabilizing gradually after subsequent cycles.
