Based on nonlinearity contact theory and the geological structure of the Xieqiao Coal Mine in the newly developed Huainan coal field,rock movements,mining fissures and deformation of overlying strata were simulated by...Based on nonlinearity contact theory and the geological structure of the Xieqiao Coal Mine in the newly developed Huainan coal field,rock movements,mining fissures and deformation of overlying strata were simulated by using the interface unit of FLAC3D to evaluate the pressure-relief gas drainage in the exploitation of super-remote protected seams.The simulation indicates that the height of the water flowing fractured zone is 54 m in the overlying strata above the protective layer.The maximum relative swelling deformation of the C13 coal seam is 0.232%,while the mining height is 3.0 m and the distance from the B8 roof to the C13 floor is 129 m,which provides good agreement with a similar experiment and in situ results.The feasibility of exploitation of a super-remote protective coal seam and the performance of the pressure-relief gas drainage in a super-remote protected layer are evaluated by comparisons with practice projects.It demonstrates that the relieved gas in the super-remote protected layers could be better drained and it is feasible to exploit the B8 coal seam before the C13 super-remote protected coal seam.The method is applicable for the study of rock movements,mining fissures and deformation of the overburden,using the interface unit to analyze the contact problems in coal mines.展开更多
Silicon(Si)has been attracting extensive attention for rechargeable lithium(Li)‐ion batteries due to its high theoretical capacity and low potential vs Li/Li+.However,it remains challenging and problematic to stabili...Silicon(Si)has been attracting extensive attention for rechargeable lithium(Li)‐ion batteries due to its high theoretical capacity and low potential vs Li/Li+.However,it remains challenging and problematic to stabilize the Si materials during electrochemical cycling because of the huge volume expansion,which results in losing electric contact and pulverization of Si particles.Consequently,the Si anode materials generally suffer from poor cycling,poor rate performance,and low coulomb efficiency,preventing them from practical applications.Up‐to‐date,there are numerous reports on the engineering of Si anode materials at microscale and nanoscale with significantly improved electrochemical performances.In this review,we will concentrate on various precisely designed protective layers for silicon‐based materials,including carbon layers,inorganic layers,and conductive polymer protective layer.First,we briefly introduced the alloying and failure mechanism of Si as anode materials upon electrochemical reactions.Following that,representative cases have been introduced and summarized to illustrate the purpose and advancement of protective coating layers,for instance,to alleviate pulverization and improve conductivity caused by volume expansion of Si particles during charge/discharge process,and maintain the surface stability of Si particles to form a stable solid‐electrolyte interphase layer.At last,possible strategies on the protective coating layer for stabilizing silicon anode materials that can be applied in the future have been indicated.展开更多
Aqueous zinc-ion batteries possess substantial potential for energy storage applications;however,they are hampered by challenges such as dendrite formation and uncontrolled side reactions occurring at the zinc anode.I...Aqueous zinc-ion batteries possess substantial potential for energy storage applications;however,they are hampered by challenges such as dendrite formation and uncontrolled side reactions occurring at the zinc anode.In our investigation,we sought to mitigate these issues through the utilization of in situ zinc complex formation reactions to engineer hydrophobic protective layers on the zinc anode surface.These robust interfacial layers serve as effective barriers,isolating the zinc anode from the electrolyte and active water molecules and thereby preventing hydrogen evolution and the generation of undesirable byproducts.Additionally,the presence of numerous zincophilic sites within these protective layers facilitates uniform zinc deposition while concurrently inhibiting dendrite growth.Through comprehensive evaluation of functional anodes featuring diverse functional groups and alkyl chain lengths,we meticulously scrutinized the underlying mechanisms influencing performance variations.This analysis involved precise modulation of interfacial hydrophobicity,rapid Zn^(2+)ion transport,and ordered deposition of Zn^(2+)ions.Notably,the optimized anode,fabricated with octadecylphosphate(OPA),demonstrated exceptional performance characteristics.The Zn//Zn symmetric cell exhibited remarkable longevity,exceeding 4000 h under a current density of 2 mA cm^(-2)and a capacity density of 2 mA h cm^(-2),Furthermore,when integrated with a VOH cathode,the complete cell exhibited superior capacity retention compared to anodes modified with alternative organic molecules.展开更多
In order to solve coal and gas outbursts during mining coal seam,studying on related problems were carried out. According to the theories of mining upper protective layer,proper mining plan were designed and performed...In order to solve coal and gas outbursts during mining coal seam,studying on related problems were carried out. According to the theories of mining upper protective layer,proper mining plan were designed and performed through field experiment. By means of examining several parameters obtained from the field experiment,the protective effects were evaluated and the protective scope and related parameters were determined. The results of field experiment show that the danger of outbursts was evidently eliminated and the method of mining protective layers is effective and the safety and economic benefits are remarkable. The research has really applied worth and will give beneficial references to mining area with analogous conditions.展开更多
Aiming at the limitation of the traditional method for determination of protection region, combined with the actual situation of a mine, a new method for determination of protection region was put forward （including ...Aiming at the limitation of the traditional method for determination of protection region, combined with the actual situation of a mine, a new method for determination of protection region was put forward （including the protection of working face layout and development direction）, that is, gas flow observation analysis on the spot and gas content contrast method. The protection region was determined by gas flow observation analysis, gas content contrast, and computer numerical simulation combined with engineering practice. In the process of gas content test, the fixed sampling method ＂big hole drill reaming, small orifice drill rod connected with core tube＂ was employed. The results show that the determined protection region is in accordance with the actual site situation. The fixed sampling method ensures the accuracy of gas measurement of gas content.展开更多
In order to understand the effect of mining height and floor lithology at the upper protective layer face on the pressure relief of protected coal seams, this paper uses a numerical simulation method to model the pres...In order to understand the effect of mining height and floor lithology at the upper protective layer face on the pressure relief of protected coal seams, this paper uses a numerical simulation method to model the pressure changes at protected coal seam during mining upper protective layer. The results show that the taller the mining height at the upper protective layer face, the greater the protection on protected coal seam due to the higher level of pressure release; the upper protective layer face with hard rock floor impedes the pressure release at the protected coal seam, which affects the overall effect of the pressure release at protected coal seam using the protective layer mining method.展开更多
In order to prevent coal and methane outbursts, mining protective layers is an effective means, yet no precedents of mining multiple protective layers is discoveried in seams which includes several seams are prone to ...In order to prevent coal and methane outbursts, mining protective layers is an effective means, yet no precedents of mining multiple protective layers is discoveried in seams which includes several seams are prone to outburst like Xinzhuangzi Mine. This paper perfected the related theories through analyzing mining multiple upper protective layers. By means of examining several parameters, it synthetically analyzed and ascer- tains the protected effectiveness and scope and reasonable parameters, finally obtained the specific indexes and effectiveness of mining multiple protective layers in coal seams cluster.展开更多
Aqueous zinc-ion batteries are regarded as promising electrochemical energy-storage systems for various applications because of their high safety,low costs,and high capacities.However,dendrite formation and side react...Aqueous zinc-ion batteries are regarded as promising electrochemical energy-storage systems for various applications because of their high safety,low costs,and high capacities.However,dendrite formation and side reactions during zinc plating or stripping greatly reduce the capacity and cycle life of a battery and subsequently limit its practical application.To address these issues,we modified the surface of a zinc anode with a functional bilayer composed of zincophilic Cu and flexible polymer layers.The zincophilic Cu interfacial layer was prepared through CuSO_(4)solution pretreatment to serve as a nucleation site to facilitate uniform Zn deposition.Meanwhile,the polymer layer was coated onto the Cu interface layer to serve as a protective layer that would prevent side reactions between zinc and electrolytes.Benefiting from the synergistic effect of the zincophilic Cu and protective polymer layers,the symmetric battery exhibits an impressive cycle life,lasting over 2900 h at a current density of 1 m A·cm^(-2)with a capacity of 1 m A·h·cm^(-2).Moreover,a full battery paired with a vanadium oxide cathode achieves a remarkable capacity retention of 72%even after 500 cycles.展开更多
All-solid-state batteries(ASSBs)have garnered significant interest as the next-generation in battery technology,praised for their superior safety and high energy density.However,a conductive agent accelerates the unde...All-solid-state batteries(ASSBs)have garnered significant interest as the next-generation in battery technology,praised for their superior safety and high energy density.However,a conductive agent accelerates the undesirable side reactions of sulfide-based solid electrolytes(SEs),resulting in poor electrochemical properties with increased interfacial resistance.Here,we propose a wet chemical method rationally designed to achieve a conformal coating of lithium-indium chloride(Li_(3)InCl_(6))onto vapor-grown carbon fibers(VGCFs)as conductive agents.First,with the advantage of the Li_(3)InCl_(6) protective layer,use of VGCF@Li_(3)InCl_(6) leads to enhanced interfacial stability and improved electrochemical properties,including stable cycle performance.These results indicate that the Li_(3)InCl_(6) protective layer suppresses the unwanted reaction between Li_(6)PS_(5)Cl(LPSCl)and VGCF.Second,VGCF@Li_(3)InCl_(6) effectively promotes polytetrafluoroethylene(PTFE)fibrillization,leading to a homogeneous electrode microstructure.The uniform distribution of the cathode active material(CAM)in the electrode results in reduced charge-transfer resistance(R_(ct))and enhanced Li-ion kinetics.As a result,a full cell with the LiNi_(x)Mn_(y)Co_(z)O_(2)(NCM)/VGCF@Li_(3)InCl_(6) electrode shows an areal capacity of 7.7mAhcm^(−2) at 0.05 C and long-term cycle stability of 77.9%over 400 cycles at 0.2 C.This study offers a strategy for utilizing stable carbon-based conductive agents in sulfide-based ASSBs to enhance their electrochemical performance.展开更多
Rechargeable aqueous zinc(Zn)-metal batteries hold great promise for next-generation energy storage systems.However,their practical application is hindered by several challenges,including dendrite formation,corrosion,...Rechargeable aqueous zinc(Zn)-metal batteries hold great promise for next-generation energy storage systems.However,their practical application is hindered by several challenges,including dendrite formation,corrosion,and the competing hydrogen evolution reaction.To address these issues,we designed and fabricated a composite protective layer for Zn anodes by integrating carbon nanotubes(CNTs)with chitosan through a simple and scalable scraping process.The CNTs ensure uniform electric field distribution due to their high electrical conductivity,while protonated chitosan regulates ion transport and suppresses dendrite formation at the anode interface.The chitosan/CNTs composite layer also facilitates smooth Zn^(2+)deposition,enhancing the stability and reversibility of the Zn anode.As a result,the chitosan/CNTs@Zn anode demonstrates exceptional cycling stability,achieving over 3000 h of plating/stripping with minimal degradation.When paired with a V_(2)O_(5)cathode,the composite-protected anode significantly improves the cycle stability and energy density of the full cell.Techno-economic analysis confirms that batteries incorporating the chitosan/CNTs protective layer outperform those with bare Zn anodes in terms of energy density and overall performance under optimized conditions.This work provides a scalable and sustainable strategy to overcome the critical challenges of aqueous Zn-metal batteries,paving the way for their practical application in next-generation energy storage systems.展开更多
The inherent safety,high theoretical specific capacity and low raw material cost of aqueous batteries make them potential candidates in large-scale energy storage.However,uncontrolled dendrite growth,parasitic reactio...The inherent safety,high theoretical specific capacity and low raw material cost of aqueous batteries make them potential candidates in large-scale energy storage.However,uncontrolled dendrite growth,parasitic reactions and sluggish mass transfer on the anode-electrolyte interface are the main challenges restricting the application prospect of aqueous zinc-ion batteries.In general,eukaryotic cells utilize specific ion channels to achieve ion migration with the merits of low energy consumption and rapid speed.Herein,migrating the concept of ion channels to aqueous batteries,a crown species encapsulated zeolitic imidazolate framework(ZIF)interfacial layer(denoted as ZIF@Crown)was ex situ decorated onto the Zn anode.Similar to biological ion channels,the ZIF@Crown layer can homogenize the distribution of Zn^(2+)on the anode,accelerate the desolvation of hydrated Zn^(2+)and reduce the energy barrier for Zn^(2+)deposition,which were verified by theoretical calculations and experimental characterizations.Benefiting from these efficacious modulation mechanisms,the Zn@ZIF@Crown symmetrical cell could achieve a long calendar life of over 1900 h and the Zn@ZIF@Crown||Cu also sustained 600 cycles with a high Coulombic efficiency(97%).Furthermore,the full cells containing ZIF@Crown layer exhibit desirable electrochemical performance.This work provides an innovative avenue toward the optimization of aqueous batteries via bionic interfacial engineering.展开更多
The effective optimization of Zn anode/protective layer interface stability,underpinned by an in-depth exploration of durable protection mechanisms,is crucial for developing artificial protective layers in high-perfor...The effective optimization of Zn anode/protective layer interface stability,underpinned by an in-depth exploration of durable protection mechanisms,is crucial for developing artificial protective layers in high-performance aqueous Zn-ion batteries(AZIBs).In this work,we present a self-regulating,continuous and dense amorphous Al_(2)O_(3-x)-2 layer(referred to as A-Al_(2)O_(3-x)-2 layer)with exceptional mechanical strength,achieved through core process control.Spectroscopic and theoretical studies reveal that the amorphous structure of Al_(2)O_(3-x)-2,featuring stable oxygen vacancies,significantly enhances Zn^(2+)transfer kinetics and promotes uniform distribution.This unique structure guides controlled Zn deposition along the(002)plane,facilitating stable cycling.Furthermore,the excellent mechanical strength of A-Al_(2)O_(3-x)-2@Zn is well maintained under extended cycling conditions,ensuring lasting interface integrity and durable protection.Under a challenging current density of 60 mA cm^(-2),the A-Al_(2)O_(3-x)-2@Zn symmetric cell demonstrates an impressive cycling lifespan of 9620 cycles.Furthermore,a full cell assembled with an A-Al_(2)O_(3-x)-2@Zn anode and an Al^(3+)-doped MnO_(2)cathode exhibits substantially improved cycling performance with 100% capacity retention after 900 cycles at 1 A g^(-1),underscoring the importance of the synergistic effects between anode and cathode materials in achieving long-life AZIBs,This work provides valuable insights into designing durable protective layers for Zn anodes in aqueous Zn-ion batteries.展开更多
In this work,we design and fabricate AlGaN/GaN-based Schottky barrier diodes(SBDs)on a silicon substrate with a trenched n^(+)-GaN cap layer.With the developed physical models,we find that the n^(+)-GaN cap layer prov...In this work,we design and fabricate AlGaN/GaN-based Schottky barrier diodes(SBDs)on a silicon substrate with a trenched n^(+)-GaN cap layer.With the developed physical models,we find that the n^(+)-GaN cap layer provides more electrons into the AlGaN/GaN channel,which is further confirmed experimentally.When compared with the reference device,this increases the two-dimensional electron gas(2DEG)density by two times and leads to a reduced specific ON-resistance(Ron,sp)of~2.4 mΩ·cm^(2).We also adopt the trenched n^(+)-GaN structure such that partial of the n^(+)-GaN is removed by using dry etching process to eliminate the surface electrical conduction when the device is set in the off-state.To suppress the surface defects that are caused by the dry etching process,we also deposit Si_(3)N_(4)layer prior to the deposition of field plate(FP),and we obtain a reduced leakage current of~8×10^(−5)A·cm^(−2)and breakdown voltage(BV)of 876 V.The Baliga’s figure of merit(BFOM)for the proposed structure is increased to~319 MW·cm^(−2).Our investigations also find that the pre-deposited Si_(3)N_(4)layer helps suppress the electron capture and transport processes,which enables the reduced dynamic R_(on,sp).展开更多
The differential cubature solution to the problem of a Mindlin plate lying on the Winkler foundation with two simply supported edges and two clamped edges was derived.Discrete numerical technology and shape functions ...The differential cubature solution to the problem of a Mindlin plate lying on the Winkler foundation with two simply supported edges and two clamped edges was derived.Discrete numerical technology and shape functions were used to ensure that the solution is suitable to irregular shaped plates.Then,the mechanical model and the solution were employed to model the protection layer that isolates the mining stopes from sea water in Sanshandao gold mine,which is the first subsea mine of China.Furthermore,thickness optimizations for the protection layers above each stope were conducted based on the maximum principle stress criterion,and the linear relations between the best protection layer thickness and the stope area under different safety factors were regressed to guide the isolation design.The method presented in this work provides a practical way to quickly design the isolation layer thickness in subsea mining.展开更多
Hot corrosion has been extensively observed in various high temperature applications,which might cause large economic losses.To deepen the insight and understanding of hot corrosion,herein,we provide a detailed discus...Hot corrosion has been extensively observed in various high temperature applications,which might cause large economic losses.To deepen the insight and understanding of hot corrosion,herein,we provide a detailed discussion on hot corrosion induced by molten sulfate salt,in which Na_(2)SO_(4)is the main chemical reactant.The hot corrosion is triggered and sustained by the negative solubility gradient of protective oxide from the oxide/salt interface to salt/gas interface.In this work,we reviewed several key factors,including temperature,gas composition,molten salt composition,alloy element and external stress,influencing the hot corrosion of alloy beneath the molten salt.The application of anti-corrosion coating seems to be the most effective and commercial mothed to mitigate hot corrosion.Therefore,the progress of the development of effective coatings,e.g.,Ni-Cr coatings,aluminide coatings,silicide coatings and MCrAlY(X)coatings,has also been summarized.展开更多
A variety of techniques, such as chemical analysis, scanning electron microscopy-energy dispersive spectroscopy, and X-ray diffraction, were applied to characterize the adhesion protective layer formed below the blast...A variety of techniques, such as chemical analysis, scanning electron microscopy-energy dispersive spectroscopy, and X-ray diffraction, were applied to characterize the adhesion protective layer formed below the blast furnace taphole level when a certain amount of titanium-bearing burden was used. Samples of the protective layer were extracted to identify the chemical composition, phase assemblage, andistribution. Furthermore, the formation mechanism of the protective layer was determined after clarifying the source of each componenFinally, a technical strategy was proposed for achieving a stable protective layer in the hearth. The results show that the protective layemainly exists in a bilayer form in the sidewall, namely, a titanium-bearing layer and a graphite layer. Both the layers contain the slag phaswhose major crystalline phase is magnesium melilite（Ca2Mg Si2O7） and the main source of the slag phase is coke ash. It is clearly determinethat solid particles such as graphite, Ti（C,N） and Mg Al2O4play an important role in the formation of the protective layer, and the key factofor promoting the formation of a stable protective layer is reasonable control of the evolution behavior of coke.展开更多
With the increase in mining depth, the danger of coal and gas outbursts increases.In order to drain coal gas effectively and to eliminate the risk of coal and gas outbursts, we used a specific number of penetration bo...With the increase in mining depth, the danger of coal and gas outbursts increases.In order to drain coal gas effectively and to eliminate the risk of coal and gas outbursts, we used a specific number of penetration boreholes for draining of pressure relief gas.Based on the principle of overlying strata movement, deformation and pressure relief, a good effect of gas drainage was obtained.The practice in the Panyi coal mine has shown that, after mining the C11coal seam as the protective layer, the relative expansion deformation value of the protected layer C13 reached 2.63%, The permeability coefficient increased 2880 times, the gas drainage rate of the C13 coal seam increased to more than 60%, the amount of gas was reduced from 13.0 to 5.2 m3/t and the gas pressure declined from 4.4 to 0.4 MPa, which caused the danger the outbursts in the coal seams to be eliminated.The result was that we achieved a safe and highly efficient mining operation of the C13 coal seam.展开更多
A long campaign life of blast furnaces is heavily linked to the existence of a protective layer in their hearths. In this work, we conducted dissection studies and investigated damage in blast furnace hearths to estim...A long campaign life of blast furnaces is heavily linked to the existence of a protective layer in their hearths. In this work, we conducted dissection studies and investigated damage in blast furnace hearths to estimate the formation mechanism of the protective layer. The results illustrate that a significant amount of graphite phase was trapped within the hearth protective layer. Furthermore, on the basis of the thermodynamic and kinetic calculations of the graphite precipitation process, a precipitation potential index related to the formation of the graphite-rich protective layer was proposed to characterize the formation ability of this layer. We determined that, under normal operating conditions, the precipitation of graphite phase ~om hot metal was thermodynamically possible. Among elements that exist in hot metal, C, Si, and P favor graphite precipitation, whereas Mn and Cr inhibit this process. Moreover, at the same hot-face temperature, an increase of carbon concentration in hot metal can shorten the precipitation time. Finally, the results suggest that measures such as reducing the hot-face tem- perature and increasing the degree of carbon saturation in hot metal are critically important to improve the precipitation potential index.展开更多
Lithium(Li)metal anodes with the high theoretical specific capacity(3860 mAh g^(-1))and most negative reduction potential(-3.04 V vs.standard hydrogen electrode)have been considered as an ultimate choice for energy st...Lithium(Li)metal anodes with the high theoretical specific capacity(3860 mAh g^(-1))and most negative reduction potential(-3.04 V vs.standard hydrogen electrode)have been considered as an ultimate choice for energy storage devices with high energy density[1-4].However,the practical applications of Li metalbased batteries(LMBs)are confronted with two tough issues:Li dendrite growth induced by uneven Li depositions and unstable solid electrolyte interphase(SEI)(Fig.1a)[5,6].展开更多
基金the National Basic Research Program of China (No.2005CB221503)the Major Program of the National Natural Science Foundation of China (No.70533050)the National Natural Science Foundation of China (No.50674089) for their support
文摘Based on nonlinearity contact theory and the geological structure of the Xieqiao Coal Mine in the newly developed Huainan coal field,rock movements,mining fissures and deformation of overlying strata were simulated by using the interface unit of FLAC3D to evaluate the pressure-relief gas drainage in the exploitation of super-remote protected seams.The simulation indicates that the height of the water flowing fractured zone is 54 m in the overlying strata above the protective layer.The maximum relative swelling deformation of the C13 coal seam is 0.232%,while the mining height is 3.0 m and the distance from the B8 roof to the C13 floor is 129 m,which provides good agreement with a similar experiment and in situ results.The feasibility of exploitation of a super-remote protective coal seam and the performance of the pressure-relief gas drainage in a super-remote protected layer are evaluated by comparisons with practice projects.It demonstrates that the relieved gas in the super-remote protected layers could be better drained and it is feasible to exploit the B8 coal seam before the C13 super-remote protected coal seam.The method is applicable for the study of rock movements,mining fissures and deformation of the overburden,using the interface unit to analyze the contact problems in coal mines.
基金Japan Society for the Promotion of Science,Grant/Award Number:18H03869National Natural Science Foundation of China,Grant/Award Numbers:51872333,51874357。
文摘Silicon(Si)has been attracting extensive attention for rechargeable lithium(Li)‐ion batteries due to its high theoretical capacity and low potential vs Li/Li+.However,it remains challenging and problematic to stabilize the Si materials during electrochemical cycling because of the huge volume expansion,which results in losing electric contact and pulverization of Si particles.Consequently,the Si anode materials generally suffer from poor cycling,poor rate performance,and low coulomb efficiency,preventing them from practical applications.Up‐to‐date,there are numerous reports on the engineering of Si anode materials at microscale and nanoscale with significantly improved electrochemical performances.In this review,we will concentrate on various precisely designed protective layers for silicon‐based materials,including carbon layers,inorganic layers,and conductive polymer protective layer.First,we briefly introduced the alloying and failure mechanism of Si as anode materials upon electrochemical reactions.Following that,representative cases have been introduced and summarized to illustrate the purpose and advancement of protective coating layers,for instance,to alleviate pulverization and improve conductivity caused by volume expansion of Si particles during charge/discharge process,and maintain the surface stability of Si particles to form a stable solid‐electrolyte interphase layer.At last,possible strategies on the protective coating layer for stabilizing silicon anode materials that can be applied in the future have been indicated.
基金financially supported by the Jiangsu Distinguished Professors Project (No.1711510024)the Funding for Scientific Research Startup of Jiangsu University (No.4111510015,19JDG044)+5 种基金the Jiangsu Provincial Program for High-Level Innovative and Entrepreneurial Talents Introductionthe National Natural Science Foundation of China (No.22008091)the Jiangsu Agriculture Science and Technology Innovation Fund (No.CX (21)1007)the Natural Science Foundation of Guangdong Province (2023A1515010894)the Open Project of Luzhou Key Laboratory of Fine Chemical Application Technology (HYJH-2302-A)the National Institute of Education,Singapore,under its Academic Research Fund (RI 1/21 EAH)。
文摘Aqueous zinc-ion batteries possess substantial potential for energy storage applications;however,they are hampered by challenges such as dendrite formation and uncontrolled side reactions occurring at the zinc anode.In our investigation,we sought to mitigate these issues through the utilization of in situ zinc complex formation reactions to engineer hydrophobic protective layers on the zinc anode surface.These robust interfacial layers serve as effective barriers,isolating the zinc anode from the electrolyte and active water molecules and thereby preventing hydrogen evolution and the generation of undesirable byproducts.Additionally,the presence of numerous zincophilic sites within these protective layers facilitates uniform zinc deposition while concurrently inhibiting dendrite growth.Through comprehensive evaluation of functional anodes featuring diverse functional groups and alkyl chain lengths,we meticulously scrutinized the underlying mechanisms influencing performance variations.This analysis involved precise modulation of interfacial hydrophobicity,rapid Zn^(2+)ion transport,and ordered deposition of Zn^(2+)ions.Notably,the optimized anode,fabricated with octadecylphosphate(OPA),demonstrated exceptional performance characteristics.The Zn//Zn symmetric cell exhibited remarkable longevity,exceeding 4000 h under a current density of 2 mA cm^(-2)and a capacity density of 2 mA h cm^(-2),Furthermore,when integrated with a VOH cathode,the complete cell exhibited superior capacity retention compared to anodes modified with alternative organic molecules.
文摘In order to solve coal and gas outbursts during mining coal seam,studying on related problems were carried out. According to the theories of mining upper protective layer,proper mining plan were designed and performed through field experiment. By means of examining several parameters obtained from the field experiment,the protective effects were evaluated and the protective scope and related parameters were determined. The results of field experiment show that the danger of outbursts was evidently eliminated and the method of mining protective layers is effective and the safety and economic benefits are remarkable. The research has really applied worth and will give beneficial references to mining area with analogous conditions.
文摘Aiming at the limitation of the traditional method for determination of protection region, combined with the actual situation of a mine, a new method for determination of protection region was put forward （including the protection of working face layout and development direction）, that is, gas flow observation analysis on the spot and gas content contrast method. The protection region was determined by gas flow observation analysis, gas content contrast, and computer numerical simulation combined with engineering practice. In the process of gas content test, the fixed sampling method ＂big hole drill reaming, small orifice drill rod connected with core tube＂ was employed. The results show that the determined protection region is in accordance with the actual site situation. The fixed sampling method ensures the accuracy of gas measurement of gas content.
文摘In order to understand the effect of mining height and floor lithology at the upper protective layer face on the pressure relief of protected coal seams, this paper uses a numerical simulation method to model the pressure changes at protected coal seam during mining upper protective layer. The results show that the taller the mining height at the upper protective layer face, the greater the protection on protected coal seam due to the higher level of pressure release; the upper protective layer face with hard rock floor impedes the pressure release at the protected coal seam, which affects the overall effect of the pressure release at protected coal seam using the protective layer mining method.
文摘In order to prevent coal and methane outbursts, mining protective layers is an effective means, yet no precedents of mining multiple protective layers is discoveried in seams which includes several seams are prone to outburst like Xinzhuangzi Mine. This paper perfected the related theories through analyzing mining multiple upper protective layers. By means of examining several parameters, it synthetically analyzed and ascer- tains the protected effectiveness and scope and reasonable parameters, finally obtained the specific indexes and effectiveness of mining multiple protective layers in coal seams cluster.
基金financially supported by the Science and Technology Development Project of Henan Province,China(No.242102241042)the Joint Fund of Henan Province Science and Technology R&D Program(No.225200810093)+1 种基金the Startup Research of Henan Academy of Sciences(No.231817001)the Key Innovation Projects for Postgraduates of Henan Academy of Sciences(No.24331712)。
文摘Aqueous zinc-ion batteries are regarded as promising electrochemical energy-storage systems for various applications because of their high safety,low costs,and high capacities.However,dendrite formation and side reactions during zinc plating or stripping greatly reduce the capacity and cycle life of a battery and subsequently limit its practical application.To address these issues,we modified the surface of a zinc anode with a functional bilayer composed of zincophilic Cu and flexible polymer layers.The zincophilic Cu interfacial layer was prepared through CuSO_(4)solution pretreatment to serve as a nucleation site to facilitate uniform Zn deposition.Meanwhile,the polymer layer was coated onto the Cu interface layer to serve as a protective layer that would prevent side reactions between zinc and electrolytes.Benefiting from the synergistic effect of the zincophilic Cu and protective polymer layers,the symmetric battery exhibits an impressive cycle life,lasting over 2900 h at a current density of 1 m A·cm^(-2)with a capacity of 1 m A·h·cm^(-2).Moreover,a full battery paired with a vanadium oxide cathode achieves a remarkable capacity retention of 72%even after 500 cycles.
基金supported by the Korea Institute for Advancement of Technology(KIAT)grant funded by the Korean Government(MOTIE)(RS-2024-00417730,HRD Program for Industrial Innovation)supported by the Technology Innovation Program(or Industrial Strategic Technology Development Program-Materials&Components Technology Development Program)(20024261),Development of thick film electrodes and cell manufacturing technology for a high-performance lithium iron phosphate battery with energy density of over 200 Wh/kg was funded by the Ministry of Trade,Industry&Energy(MOTIE,Korea).
文摘All-solid-state batteries(ASSBs)have garnered significant interest as the next-generation in battery technology,praised for their superior safety and high energy density.However,a conductive agent accelerates the undesirable side reactions of sulfide-based solid electrolytes(SEs),resulting in poor electrochemical properties with increased interfacial resistance.Here,we propose a wet chemical method rationally designed to achieve a conformal coating of lithium-indium chloride(Li_(3)InCl_(6))onto vapor-grown carbon fibers(VGCFs)as conductive agents.First,with the advantage of the Li_(3)InCl_(6) protective layer,use of VGCF@Li_(3)InCl_(6) leads to enhanced interfacial stability and improved electrochemical properties,including stable cycle performance.These results indicate that the Li_(3)InCl_(6) protective layer suppresses the unwanted reaction between Li_(6)PS_(5)Cl(LPSCl)and VGCF.Second,VGCF@Li_(3)InCl_(6) effectively promotes polytetrafluoroethylene(PTFE)fibrillization,leading to a homogeneous electrode microstructure.The uniform distribution of the cathode active material(CAM)in the electrode results in reduced charge-transfer resistance(R_(ct))and enhanced Li-ion kinetics.As a result,a full cell with the LiNi_(x)Mn_(y)Co_(z)O_(2)(NCM)/VGCF@Li_(3)InCl_(6) electrode shows an areal capacity of 7.7mAhcm^(−2) at 0.05 C and long-term cycle stability of 77.9%over 400 cycles at 0.2 C.This study offers a strategy for utilizing stable carbon-based conductive agents in sulfide-based ASSBs to enhance their electrochemical performance.
基金supported by the National Natural Science Foundation of China(22279139,62227815,22465026,22469015)the National Key R&D Program of China(2022YFA1504500)+1 种基金the Natural Science Foundation of Inner Mongolia Autonomous Region of China(2024JQ06,2022MS2010,2024MS05005)Inner Mongolia University Postgraduate Scientific Research Innovation Project(11200-5223737)。
文摘Rechargeable aqueous zinc(Zn)-metal batteries hold great promise for next-generation energy storage systems.However,their practical application is hindered by several challenges,including dendrite formation,corrosion,and the competing hydrogen evolution reaction.To address these issues,we designed and fabricated a composite protective layer for Zn anodes by integrating carbon nanotubes(CNTs)with chitosan through a simple and scalable scraping process.The CNTs ensure uniform electric field distribution due to their high electrical conductivity,while protonated chitosan regulates ion transport and suppresses dendrite formation at the anode interface.The chitosan/CNTs composite layer also facilitates smooth Zn^(2+)deposition,enhancing the stability and reversibility of the Zn anode.As a result,the chitosan/CNTs@Zn anode demonstrates exceptional cycling stability,achieving over 3000 h of plating/stripping with minimal degradation.When paired with a V_(2)O_(5)cathode,the composite-protected anode significantly improves the cycle stability and energy density of the full cell.Techno-economic analysis confirms that batteries incorporating the chitosan/CNTs protective layer outperform those with bare Zn anodes in terms of energy density and overall performance under optimized conditions.This work provides a scalable and sustainable strategy to overcome the critical challenges of aqueous Zn-metal batteries,paving the way for their practical application in next-generation energy storage systems.
基金supported by research grants from the National Key Research and Development Program of China(No.2022YFB3803300)the Natural Science Foundation of China(Nos.52173235 and 62074022)+2 种基金the Venture&Innovation Support Program for Chongqing Overseas Returnees(No.CX2021018)the Youth Talent Support Program of Chongqing(No.CQYC2021059206)the Program of Graduate Education and Teaching in Chongqing(No.yjg223016).
文摘The inherent safety,high theoretical specific capacity and low raw material cost of aqueous batteries make them potential candidates in large-scale energy storage.However,uncontrolled dendrite growth,parasitic reactions and sluggish mass transfer on the anode-electrolyte interface are the main challenges restricting the application prospect of aqueous zinc-ion batteries.In general,eukaryotic cells utilize specific ion channels to achieve ion migration with the merits of low energy consumption and rapid speed.Herein,migrating the concept of ion channels to aqueous batteries,a crown species encapsulated zeolitic imidazolate framework(ZIF)interfacial layer(denoted as ZIF@Crown)was ex situ decorated onto the Zn anode.Similar to biological ion channels,the ZIF@Crown layer can homogenize the distribution of Zn^(2+)on the anode,accelerate the desolvation of hydrated Zn^(2+)and reduce the energy barrier for Zn^(2+)deposition,which were verified by theoretical calculations and experimental characterizations.Benefiting from these efficacious modulation mechanisms,the Zn@ZIF@Crown symmetrical cell could achieve a long calendar life of over 1900 h and the Zn@ZIF@Crown||Cu also sustained 600 cycles with a high Coulombic efficiency(97%).Furthermore,the full cells containing ZIF@Crown layer exhibit desirable electrochemical performance.This work provides an innovative avenue toward the optimization of aqueous batteries via bionic interfacial engineering.
基金financially supported by the National Natural Science Foundation of China(42377487,42307582)the Guangdong Basic and Applied Basic Research Foundation(2022A1515110477,2022B1515120019)Support Project of Guangzhou Association for Science and Technology(QT2024-07)。
文摘The effective optimization of Zn anode/protective layer interface stability,underpinned by an in-depth exploration of durable protection mechanisms,is crucial for developing artificial protective layers in high-performance aqueous Zn-ion batteries(AZIBs).In this work,we present a self-regulating,continuous and dense amorphous Al_(2)O_(3-x)-2 layer(referred to as A-Al_(2)O_(3-x)-2 layer)with exceptional mechanical strength,achieved through core process control.Spectroscopic and theoretical studies reveal that the amorphous structure of Al_(2)O_(3-x)-2,featuring stable oxygen vacancies,significantly enhances Zn^(2+)transfer kinetics and promotes uniform distribution.This unique structure guides controlled Zn deposition along the(002)plane,facilitating stable cycling.Furthermore,the excellent mechanical strength of A-Al_(2)O_(3-x)-2@Zn is well maintained under extended cycling conditions,ensuring lasting interface integrity and durable protection.Under a challenging current density of 60 mA cm^(-2),the A-Al_(2)O_(3-x)-2@Zn symmetric cell demonstrates an impressive cycling lifespan of 9620 cycles.Furthermore,a full cell assembled with an A-Al_(2)O_(3-x)-2@Zn anode and an Al^(3+)-doped MnO_(2)cathode exhibits substantially improved cycling performance with 100% capacity retention after 900 cycles at 1 A g^(-1),underscoring the importance of the synergistic effects between anode and cathode materials in achieving long-life AZIBs,This work provides valuable insights into designing durable protective layers for Zn anodes in aqueous Zn-ion batteries.
基金supported by National Natural Science Foundation of China under grant U23A20361Key Area R&D Program of Guangdong Province under grant 2022B0701180001.
文摘In this work,we design and fabricate AlGaN/GaN-based Schottky barrier diodes(SBDs)on a silicon substrate with a trenched n^(+)-GaN cap layer.With the developed physical models,we find that the n^(+)-GaN cap layer provides more electrons into the AlGaN/GaN channel,which is further confirmed experimentally.When compared with the reference device,this increases the two-dimensional electron gas(2DEG)density by two times and leads to a reduced specific ON-resistance(Ron,sp)of~2.4 mΩ·cm^(2).We also adopt the trenched n^(+)-GaN structure such that partial of the n^(+)-GaN is removed by using dry etching process to eliminate the surface electrical conduction when the device is set in the off-state.To suppress the surface defects that are caused by the dry etching process,we also deposit Si_(3)N_(4)layer prior to the deposition of field plate(FP),and we obtain a reduced leakage current of~8×10^(−5)A·cm^(−2)and breakdown voltage(BV)of 876 V.The Baliga’s figure of merit(BFOM)for the proposed structure is increased to~319 MW·cm^(−2).Our investigations also find that the pre-deposited Si_(3)N_(4)layer helps suppress the electron capture and transport processes,which enables the reduced dynamic R_(on,sp).
基金Projects(51504044,51204100)supported by National Natural Science Foundation of ChinaProject(14KF05)supported by the Research Fund of The State Key Laboratory of Coal Resources and Mine Safety,CUMT,China+3 种基金Project(cstc2016jcyj A1861)supported by the Research Fund of Chongqing Basic Science and Cutting-Edge Technology Special Projects,ChinaProject(2015CDJXY)supported by the Fundamental Research Funds for the Central UniversitiesProject supported by the China Postdoctoral Science FoundationProject(2011DA105287-MS201503)supported by the Independent Subject of State Key Laboratory of Coal Mine Disaster Dynamics and Control,China
文摘The differential cubature solution to the problem of a Mindlin plate lying on the Winkler foundation with two simply supported edges and two clamped edges was derived.Discrete numerical technology and shape functions were used to ensure that the solution is suitable to irregular shaped plates.Then,the mechanical model and the solution were employed to model the protection layer that isolates the mining stopes from sea water in Sanshandao gold mine,which is the first subsea mine of China.Furthermore,thickness optimizations for the protection layers above each stope were conducted based on the maximum principle stress criterion,and the linear relations between the best protection layer thickness and the stope area under different safety factors were regressed to guide the isolation design.The method presented in this work provides a practical way to quickly design the isolation layer thickness in subsea mining.
基金funded by the U.S.Department of Energy,National Energy Technology Laboratory(NETL)under the contract number DE-FE0031548。
文摘Hot corrosion has been extensively observed in various high temperature applications,which might cause large economic losses.To deepen the insight and understanding of hot corrosion,herein,we provide a detailed discussion on hot corrosion induced by molten sulfate salt,in which Na_(2)SO_(4)is the main chemical reactant.The hot corrosion is triggered and sustained by the negative solubility gradient of protective oxide from the oxide/salt interface to salt/gas interface.In this work,we reviewed several key factors,including temperature,gas composition,molten salt composition,alloy element and external stress,influencing the hot corrosion of alloy beneath the molten salt.The application of anti-corrosion coating seems to be the most effective and commercial mothed to mitigate hot corrosion.Therefore,the progress of the development of effective coatings,e.g.,Ni-Cr coatings,aluminide coatings,silicide coatings and MCrAlY(X)coatings,has also been summarized.
基金financially supported by the Natural Science Foundation of China(No.51304014)the Natural Science Foundation of China and Baosteel(No.51134008)the National Basic Research Program of China(No.2012CB720401)
文摘A variety of techniques, such as chemical analysis, scanning electron microscopy-energy dispersive spectroscopy, and X-ray diffraction, were applied to characterize the adhesion protective layer formed below the blast furnace taphole level when a certain amount of titanium-bearing burden was used. Samples of the protective layer were extracted to identify the chemical composition, phase assemblage, andistribution. Furthermore, the formation mechanism of the protective layer was determined after clarifying the source of each componenFinally, a technical strategy was proposed for achieving a stable protective layer in the hearth. The results show that the protective layemainly exists in a bilayer form in the sidewall, namely, a titanium-bearing layer and a graphite layer. Both the layers contain the slag phaswhose major crystalline phase is magnesium melilite（Ca2Mg Si2O7） and the main source of the slag phase is coke ash. It is clearly determinethat solid particles such as graphite, Ti（C,N） and Mg Al2O4play an important role in the formation of the protective layer, and the key factofor promoting the formation of a stable protective layer is reasonable control of the evolution behavior of coke.
基金Projects 2005CB221503 supported by the National Basic Research Program of China70533050 and 50674089 by the National Natural Science Foundationof China
文摘With the increase in mining depth, the danger of coal and gas outbursts increases.In order to drain coal gas effectively and to eliminate the risk of coal and gas outbursts, we used a specific number of penetration boreholes for draining of pressure relief gas.Based on the principle of overlying strata movement, deformation and pressure relief, a good effect of gas drainage was obtained.The practice in the Panyi coal mine has shown that, after mining the C11coal seam as the protective layer, the relative expansion deformation value of the protected layer C13 reached 2.63%, The permeability coefficient increased 2880 times, the gas drainage rate of the C13 coal seam increased to more than 60%, the amount of gas was reduced from 13.0 to 5.2 m3/t and the gas pressure declined from 4.4 to 0.4 MPa, which caused the danger the outbursts in the coal seams to be eliminated.The result was that we achieved a safe and highly efficient mining operation of the C13 coal seam.
基金supported the National Science Foundation for Young Scientists of China (No. 51304014)the Open Foundation of the State Key Laboratory of Advanced Metallurgy (No. 41603007)
文摘A long campaign life of blast furnaces is heavily linked to the existence of a protective layer in their hearths. In this work, we conducted dissection studies and investigated damage in blast furnace hearths to estimate the formation mechanism of the protective layer. The results illustrate that a significant amount of graphite phase was trapped within the hearth protective layer. Furthermore, on the basis of the thermodynamic and kinetic calculations of the graphite precipitation process, a precipitation potential index related to the formation of the graphite-rich protective layer was proposed to characterize the formation ability of this layer. We determined that, under normal operating conditions, the precipitation of graphite phase ~om hot metal was thermodynamically possible. Among elements that exist in hot metal, C, Si, and P favor graphite precipitation, whereas Mn and Cr inhibit this process. Moreover, at the same hot-face temperature, an increase of carbon concentration in hot metal can shorten the precipitation time. Finally, the results suggest that measures such as reducing the hot-face tem- perature and increasing the degree of carbon saturation in hot metal are critically important to improve the precipitation potential index.
基金supported by National Key Research and Development Program,China(2016YFA0202500 and 2016YFA0200102)National Natural Science Foundation of China,China(21805161,21808124,U1932220)Fundamental Research Funds for the Central Universites of Central South University,China(2020zzts471)。
文摘Lithium(Li)metal anodes with the high theoretical specific capacity(3860 mAh g^(-1))and most negative reduction potential(-3.04 V vs.standard hydrogen electrode)have been considered as an ultimate choice for energy storage devices with high energy density[1-4].However,the practical applications of Li metalbased batteries(LMBs)are confronted with two tough issues:Li dendrite growth induced by uneven Li depositions and unstable solid electrolyte interphase(SEI)(Fig.1a)[5,6].
