The Metal Stable Isotope Geochemistry Laboratory(MSIGL)at the University of Science and Technology of China has developed state-of-the-art analytical methods for twelve stable isotope systems,including Mg,Si,V,Fe,Cu,Z...The Metal Stable Isotope Geochemistry Laboratory(MSIGL)at the University of Science and Technology of China has developed state-of-the-art analytical methods for twelve stable isotope systems,including Mg,Si,V,Fe,Cu,Zn,Rb,Sr,Ag,Cd,Ba,and U.Geological and biological samples were first digested by acid dissolution or alkali dissolution.The target element was subsequently purified by the column chromatography method.A Neptune Plus MC-ICP-MS was used to measure isotope compositions and the isotope bias caused during measurements was calibrated by standard bracketing and/or the double spike method.The analytical procedure was carefully checked to ensure the high precision and accuracy of the data.Here,we summarized the protocol of these established methods and compiled the standard data measured at our lab as well as those reported in literature.This comprehensive dataset can serve as a reliable benchmark for calibration,method validation,and quality assurance in metal stable isotope analyses.展开更多
The properties of electrolytes are critical for fast-charging and stable-cycling applications in lithium metal batteries(LMBs).However,the slow kinetics of Li^(+)transport and desolvation in commercial carbonate elect...The properties of electrolytes are critical for fast-charging and stable-cycling applications in lithium metal batteries(LMBs).However,the slow kinetics of Li^(+)transport and desolvation in commercial carbonate electrolytes,cou pled with the formation of unstable solid electrolyte interphases(SEI),exacerbate the degradation of LMB performance at high current densities.Herein,we propose a versatile electrolyte design strategy that incorporates cyclohexyl methyl ether(CME)as a co-solvent to reshape the Li^(+)solvation environment by the steric-hindrance effect of bulky molecules and their competitive coordination with other solvent molecules.Simulation calculations and spectral analysis demonstrate that the addition of CME molecules reduces the involvement of other solvent molecules in the Li solvation sheath and promotes the formation of Li^(+)-PF_(6)^(-)coordination,thereby accelerating Li^(+)transport kinetics.Additionally,this electrolyte composition improves Li^(+)desolvation kinetics and fosters the formation of inorganic-rich SEI,ensuring cycle stability under fast charging.Consequently,the Li‖LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)battery with the modified electrolyte retains 82% of its initial capacity after 463 cycles at 1 C.Even under the extreme fast-charging condition of 5 C,the battery can maintain 80% capacity retention after 173 cycles.This work provides a promising approach for the development of highperformance LMBs by modulating solvation environment of electrolytes.展开更多
Biomarker and stable carbon isotope analyses are presented for the Garau Formation of the Cretaceous Age,an important source rock in western Iran,to reveal its potential as an oilprone source rock.The C_(28)/C_(29)ste...Biomarker and stable carbon isotope analyses are presented for the Garau Formation of the Cretaceous Age,an important source rock in western Iran,to reveal its potential as an oilprone source rock.The C_(28)/C_(29)sterane ratio value range(0.72 to 0.83)of bitumen samples from the formation suggests that they were likely formed during phytoplankton blooms.Sterane,hopane,and isoprenoid/n-alkane ratios indicate that the formation's organic matter predominantly consists of algae,and bacteria,accompanied by some reworked material derived from higher plants.Due to the predominance of anoxic conditions and the actions of sulfate-reducing bacteria,the bitumen present is enriched with sulfur compounds.The percentages of saturates,aromatics,and nitrogen-sulfuroxygen(NSO)fractions in the bitumen samples classify them as naphthenic oils.Isotope analysis reveals that biodegradation and water-washing have reduced the concentrations of some volatile saturates and low molecular weight aromatics in the bitumen samples.These actions have resulted in distinctiveδ^(13)C values for the formation's kerogen and bitumen fractions.The formation's organic matter has been subjected to high-temperature thermal regimes and has entered the oil-generation window at the sampled localities,with vitrinite reflectance(%R_(C))varying between 0.7%and 0.75%.展开更多
Aqueous zinc-ion batteries (AZIBs) are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc (Zn) deposition and hydrogen evolution.Particularly,the ...Aqueous zinc-ion batteries (AZIBs) are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc (Zn) deposition and hydrogen evolution.Particularly,the intricate mechanisms behind the electrochemical discrepancies induced by interfacial Zn^(2+)-solvation and deposition behavior demand comprehensive investigation.Organic molecules endowed with special functional groups (such as hydroxyl,carboxyl,etc.) have the potential to significantly optimize the solvation structure of Zn^(2+)and regulate the interfacial electric double layer (EDL).By increasing nucleation overpotential and decreasing interfacial free energy,these functional groups facilitate a lower critical nucleation radius,thereby forming an asymptotic nucleation model to promote uniform Zn deposition.Herein,this study presents a pioneering approach by introducing trace amounts of n-butanol as solvation regulators to engineer the homogenized Zn (H-Zn) anode with a uniform and dense structure.The interfacial reaction and structure evolution are explored by in/ex-situ experimental techniques,indicating that the H-Zn anode exhibits dendrite-free growth,no by-products,and weak hydrogen evolution,in sharp contrast to the bare Zn.Consequently,the H-Zn anode achieves a remarkable Zn utilization rate of approximately 20% and simultaneously sustains a prolonged cycle life exceeding 500 h.Moreover,the H-Zn//NH_(4)V_(4)O^(10)(NVO) full battery showcases exceptional cycle stability,retaining 95.04%capacity retention after 400 cycles at a large current density of 5 A g^(-1).This study enlightens solvation-regulated additives to develop Zn anode with superior utilization efficiency and extended operational lifespan.展开更多
Despite the promising progress in conductive hydrogels made with pure conducting polymer,great challenges remain in the interface adhesion and robustness in longterm monitoring.To address these challenges,Prof.Seung H...Despite the promising progress in conductive hydrogels made with pure conducting polymer,great challenges remain in the interface adhesion and robustness in longterm monitoring.To address these challenges,Prof.Seung Hwan Ko and Taek-Soo Kim’s team introduced a laserinduced phase separation and adhesion method for fabricating conductive hydrogels consisting of pure poly(3,4-ethylenedioxythiophene):polystyrene sulfonate on polymer substrates.The laser-induced phase separation and adhesion treated conducting polymers can be selectively transformed into conductive hydrogels that exhibit wet conductivities of 101.4 S cm^(−1) with a spatial resolution down to 5μm.Moreover,they maintain impedance and charge-storage capacity even after 1 h of sonication.The micropatterned electrode arrays demonstrate their potential in long-term in vivo signal recordings,highlighting their promising role in the field of bioelectronics.展开更多
In this paper,we study the Bowen entropy of stable sets in positive entropy G-system of amenable group actions.The lower bound of the Bowen entropy of these sets are estimated.
The residues of Al^(3+),Ga^(3+),and In^(3+)in the environment pose an increasingly serious threat to human health and ecosystems.However,their specific and rapid detection remains challenging.In this study,we present ...The residues of Al^(3+),Ga^(3+),and In^(3+)in the environment pose an increasingly serious threat to human health and ecosystems.However,their specific and rapid detection remains challenging.In this study,we present a water‑stable cadmium metal‑organic framework(Cd‑MOF)based luminescence probe,which can detect Al^(3+),Ga^(3+),and In^(3+)ions in aqueous solutions via a luminescence“turn‑on”mode.The corresponding detection limits for the Al^(3+),Ga^(3+),and In^(3+)ions were 2.31,3.06,and 2.78μmol·L^(-1),respectively.This probe operated effectively within a pH range of 3‑10 in an all‑aqueous environment.Investigations into the detection mechanism revealed that this“turn‑on”recognition is attributed to the formation of new structures upon ion interaction.展开更多
针对现有无数据模型窃取攻击技术在有限的查询预算下难以拟合原始训练集分布,进而影响对目标模型决策边界拟合效果问题,提出了一种基于Stable Diffusion的模型窃取攻击方法(Model Extraction Attack Based on Stable Diffusion,MEASD)....针对现有无数据模型窃取攻击技术在有限的查询预算下难以拟合原始训练集分布,进而影响对目标模型决策边界拟合效果问题,提出了一种基于Stable Diffusion的模型窃取攻击方法(Model Extraction Attack Based on Stable Diffusion,MEASD).利用预训练的Stable Diffusion生成训练数据可能涵盖多个域,并包含大量非判别性样本,设计了ILAF方法以优化Stable Diffusion生成的数据品质.将高质量合成数据的原始样本与由对抗样本生成器生成的对抗样本组成替代训练集.由DPA模块组合的替代模型基于替代训练集拟合目标模型的决策边界.实验结果表明,在四个主流的基准数据集上与EBFA和DMEAE方法相比,所提的MEASD方法能够将目标模型决策边界的拟合程度提高至84%,对目标模型的黑盒对抗攻击成功率超过68%,并且查询预算较低.MEASD方法能够有效地提升目标模型决策边界拟合效果及攻击成功率.展开更多
In many places across the globe,including the Wassa District of Ghana,groundwater provides a significant supply of water for various purposes.Understanding the groundwater origin and hydrogeochemical processes control...In many places across the globe,including the Wassa District of Ghana,groundwater provides a significant supply of water for various purposes.Understanding the groundwater origin and hydrogeochemical processes controlling the groundwater chemistry is a major step in the sustainable management of the aquifers.A total of 29groundwater samples were collected and analysed.Ionic ratio graphs,multivariate statistical analysis,mineral saturation indices,stable isotopes,and geostatistics methods were used to examine the sources and the quality of the groundwater.The findings describe the water types in the district as Ca-Mg-HCO_(3)-Cl,Ca-Na-HCO_(3),Na-Ca-HCO_(3),Ca-Na-HCO_(3)-Cl,Na-Ca-HCO_(3)-Cl,mix water type,NaHCO_(3)-Cl,with possible evolution to Ca-Na-Cl-HCO_(3),and Na-Ca-Cl-HCO_(3).According to the IEWQI for drinking water,around 53.6% of the samples have good quality,whereas 10.7% have very low-quality groundwater.Only 3.45% of the samples are suitable to use for irrigation without treatment,whereas 41.4% are somewhat safe with minimal treatment.Water-rock interactions,including the dissolution and weathering of silicate minerals,cation exchange processes,and human activities like mining andquarrying,are some of the main factors influencing groundwater chemistry.Principal component analysis revealed that groundwater chemistry is influenced by a combination of natural and anthropogenic sources.The APCs-MLR receptor model quantifies the factors that play important roles in groundwater salinization,including mineral dissolution and weathering(19.4%),localised Cd(16%),Ni(14.6%),Pb(12.8%),and Fe(11.4%)contamination from urbanisation while unidentified sources of pollution account for about 26.0%.The stable isotopes revealed groundwater is of meteoric origin and water-rock interaction the major mechanism for groundwater mineralization.The results of this research highlight the need of implementing an integrated strategy for managing and accessing groundwater quality.展开更多
Scintillator is a key material for the development of X-ray detectors,which has a promising application in medical imaging,security inspection and industrial non-injury detection.The majority of scintillators currentl...Scintillator is a key material for the development of X-ray detectors,which has a promising application in medical imaging,security inspection and industrial non-injury detection.The majority of scintillators currently used in imaging are real-time imaging scintillators,which can cause ionization radiation damage to biological subjects or detection equipment during the imaging process and require complex,highly sensitive detection systems.Therefore,exploring stable,environmentally friendly scintillator materials that can achieve delayed imaging is of significance in the field of imaging.Herein,we devel-oped an X-ray time-lapse imaging scintillator,Sr_(2)Al_(6)O_(11):Dy^(3+)phosphor,which generates stable traps by X-ray irradiation,thus endowing it with excellent persistent luminescence and information storage properties(>42 d).Moreover,traps constructed by X-ray can be repeatedly refilled(>40 times)under UV light and carriers are released in theform of mechanical or thermal excitation when refilling is complete.By constructing the traps in the phosphor during X-ray excitation and using it for repetitive imaging,the detection limit is 74.78 nGy/s,and the spatial imaging resolution is as high as 16 lp/mm.This discovery providesa new idea for the development oftime-delayed X-ray scintillator.展开更多
基金the National Science Foundation of China(Nos.42273007 and 42473008)the Distinguished Young Scholars of Anhui,China(No.2408085J021)。
文摘The Metal Stable Isotope Geochemistry Laboratory(MSIGL)at the University of Science and Technology of China has developed state-of-the-art analytical methods for twelve stable isotope systems,including Mg,Si,V,Fe,Cu,Zn,Rb,Sr,Ag,Cd,Ba,and U.Geological and biological samples were first digested by acid dissolution or alkali dissolution.The target element was subsequently purified by the column chromatography method.A Neptune Plus MC-ICP-MS was used to measure isotope compositions and the isotope bias caused during measurements was calibrated by standard bracketing and/or the double spike method.The analytical procedure was carefully checked to ensure the high precision and accuracy of the data.Here,we summarized the protocol of these established methods and compiled the standard data measured at our lab as well as those reported in literature.This comprehensive dataset can serve as a reliable benchmark for calibration,method validation,and quality assurance in metal stable isotope analyses.
基金supported by the Lithium Resources and Lithium Materials Key Laboratory of Sichuan Province(LRMKF202405)the National Natural Science Foundation of China(52402226)+3 种基金the Natural Science Foundation of Sichuan Province(2024NSFSC1016)the Scientific Research Startup Foundation of Chengdu University of Technology(10912-KYQD2023-10240)the opening funding from Key Laboratory of Engineering Dielectrics and Its Application(Harbin University of Science and Technology)(KFM202507,Ministry of Education)the funding provided by the Alexander von Humboldt Foundation。
文摘The properties of electrolytes are critical for fast-charging and stable-cycling applications in lithium metal batteries(LMBs).However,the slow kinetics of Li^(+)transport and desolvation in commercial carbonate electrolytes,cou pled with the formation of unstable solid electrolyte interphases(SEI),exacerbate the degradation of LMB performance at high current densities.Herein,we propose a versatile electrolyte design strategy that incorporates cyclohexyl methyl ether(CME)as a co-solvent to reshape the Li^(+)solvation environment by the steric-hindrance effect of bulky molecules and their competitive coordination with other solvent molecules.Simulation calculations and spectral analysis demonstrate that the addition of CME molecules reduces the involvement of other solvent molecules in the Li solvation sheath and promotes the formation of Li^(+)-PF_(6)^(-)coordination,thereby accelerating Li^(+)transport kinetics.Additionally,this electrolyte composition improves Li^(+)desolvation kinetics and fosters the formation of inorganic-rich SEI,ensuring cycle stability under fast charging.Consequently,the Li‖LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)battery with the modified electrolyte retains 82% of its initial capacity after 463 cycles at 1 C.Even under the extreme fast-charging condition of 5 C,the battery can maintain 80% capacity retention after 173 cycles.This work provides a promising approach for the development of highperformance LMBs by modulating solvation environment of electrolytes.
文摘Biomarker and stable carbon isotope analyses are presented for the Garau Formation of the Cretaceous Age,an important source rock in western Iran,to reveal its potential as an oilprone source rock.The C_(28)/C_(29)sterane ratio value range(0.72 to 0.83)of bitumen samples from the formation suggests that they were likely formed during phytoplankton blooms.Sterane,hopane,and isoprenoid/n-alkane ratios indicate that the formation's organic matter predominantly consists of algae,and bacteria,accompanied by some reworked material derived from higher plants.Due to the predominance of anoxic conditions and the actions of sulfate-reducing bacteria,the bitumen present is enriched with sulfur compounds.The percentages of saturates,aromatics,and nitrogen-sulfuroxygen(NSO)fractions in the bitumen samples classify them as naphthenic oils.Isotope analysis reveals that biodegradation and water-washing have reduced the concentrations of some volatile saturates and low molecular weight aromatics in the bitumen samples.These actions have resulted in distinctiveδ^(13)C values for the formation's kerogen and bitumen fractions.The formation's organic matter has been subjected to high-temperature thermal regimes and has entered the oil-generation window at the sampled localities,with vitrinite reflectance(%R_(C))varying between 0.7%and 0.75%.
基金National Natural Science Foundation of China (52301273, 52072411)Science and Technology Innovation Program of Hunan Province (2024RC3222)+3 种基金Key project of scientific research project of Hunan Provincial Department of Education (22A0479)China Postdoctoral Science Foundation (2024M753668)Central South University Innovation-Driven Research Programme (2023CXQD038)Hunan Provincial Postgraduate Research Innovation Programme(CX20240970)。
文摘Aqueous zinc-ion batteries (AZIBs) are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc (Zn) deposition and hydrogen evolution.Particularly,the intricate mechanisms behind the electrochemical discrepancies induced by interfacial Zn^(2+)-solvation and deposition behavior demand comprehensive investigation.Organic molecules endowed with special functional groups (such as hydroxyl,carboxyl,etc.) have the potential to significantly optimize the solvation structure of Zn^(2+)and regulate the interfacial electric double layer (EDL).By increasing nucleation overpotential and decreasing interfacial free energy,these functional groups facilitate a lower critical nucleation radius,thereby forming an asymptotic nucleation model to promote uniform Zn deposition.Herein,this study presents a pioneering approach by introducing trace amounts of n-butanol as solvation regulators to engineer the homogenized Zn (H-Zn) anode with a uniform and dense structure.The interfacial reaction and structure evolution are explored by in/ex-situ experimental techniques,indicating that the H-Zn anode exhibits dendrite-free growth,no by-products,and weak hydrogen evolution,in sharp contrast to the bare Zn.Consequently,the H-Zn anode achieves a remarkable Zn utilization rate of approximately 20% and simultaneously sustains a prolonged cycle life exceeding 500 h.Moreover,the H-Zn//NH_(4)V_(4)O^(10)(NVO) full battery showcases exceptional cycle stability,retaining 95.04%capacity retention after 400 cycles at a large current density of 5 A g^(-1).This study enlightens solvation-regulated additives to develop Zn anode with superior utilization efficiency and extended operational lifespan.
基金supported by the National Natural Science Foundation of China(52475610)Zhejiang Provincial Natural Science Foundation of China(LDQ24E050001).
文摘Despite the promising progress in conductive hydrogels made with pure conducting polymer,great challenges remain in the interface adhesion and robustness in longterm monitoring.To address these challenges,Prof.Seung Hwan Ko and Taek-Soo Kim’s team introduced a laserinduced phase separation and adhesion method for fabricating conductive hydrogels consisting of pure poly(3,4-ethylenedioxythiophene):polystyrene sulfonate on polymer substrates.The laser-induced phase separation and adhesion treated conducting polymers can be selectively transformed into conductive hydrogels that exhibit wet conductivities of 101.4 S cm^(−1) with a spatial resolution down to 5μm.Moreover,they maintain impedance and charge-storage capacity even after 1 h of sonication.The micropatterned electrode arrays demonstrate their potential in long-term in vivo signal recordings,highlighting their promising role in the field of bioelectronics.
基金Supported by NSFC(No.11861010),also supported by NSFC(No.12171175),also supported by NSFC(No.12261006)NSF of Guangxi Province(No.2018GXNSFFA281008)Project of Guangxi First Class Disciplines of Statistics(No.GJKY-2022-01)。
文摘In this paper,we study the Bowen entropy of stable sets in positive entropy G-system of amenable group actions.The lower bound of the Bowen entropy of these sets are estimated.
文摘The residues of Al^(3+),Ga^(3+),and In^(3+)in the environment pose an increasingly serious threat to human health and ecosystems.However,their specific and rapid detection remains challenging.In this study,we present a water‑stable cadmium metal‑organic framework(Cd‑MOF)based luminescence probe,which can detect Al^(3+),Ga^(3+),and In^(3+)ions in aqueous solutions via a luminescence“turn‑on”mode.The corresponding detection limits for the Al^(3+),Ga^(3+),and In^(3+)ions were 2.31,3.06,and 2.78μmol·L^(-1),respectively.This probe operated effectively within a pH range of 3‑10 in an all‑aqueous environment.Investigations into the detection mechanism revealed that this“turn‑on”recognition is attributed to the formation of new structures upon ion interaction.
文摘针对现有无数据模型窃取攻击技术在有限的查询预算下难以拟合原始训练集分布,进而影响对目标模型决策边界拟合效果问题,提出了一种基于Stable Diffusion的模型窃取攻击方法(Model Extraction Attack Based on Stable Diffusion,MEASD).利用预训练的Stable Diffusion生成训练数据可能涵盖多个域,并包含大量非判别性样本,设计了ILAF方法以优化Stable Diffusion生成的数据品质.将高质量合成数据的原始样本与由对抗样本生成器生成的对抗样本组成替代训练集.由DPA模块组合的替代模型基于替代训练集拟合目标模型的决策边界.实验结果表明,在四个主流的基准数据集上与EBFA和DMEAE方法相比,所提的MEASD方法能够将目标模型决策边界的拟合程度提高至84%,对目标模型的黑盒对抗攻击成功率超过68%,并且查询预算较低.MEASD方法能够有效地提升目标模型决策边界拟合效果及攻击成功率.
文摘In many places across the globe,including the Wassa District of Ghana,groundwater provides a significant supply of water for various purposes.Understanding the groundwater origin and hydrogeochemical processes controlling the groundwater chemistry is a major step in the sustainable management of the aquifers.A total of 29groundwater samples were collected and analysed.Ionic ratio graphs,multivariate statistical analysis,mineral saturation indices,stable isotopes,and geostatistics methods were used to examine the sources and the quality of the groundwater.The findings describe the water types in the district as Ca-Mg-HCO_(3)-Cl,Ca-Na-HCO_(3),Na-Ca-HCO_(3),Ca-Na-HCO_(3)-Cl,Na-Ca-HCO_(3)-Cl,mix water type,NaHCO_(3)-Cl,with possible evolution to Ca-Na-Cl-HCO_(3),and Na-Ca-Cl-HCO_(3).According to the IEWQI for drinking water,around 53.6% of the samples have good quality,whereas 10.7% have very low-quality groundwater.Only 3.45% of the samples are suitable to use for irrigation without treatment,whereas 41.4% are somewhat safe with minimal treatment.Water-rock interactions,including the dissolution and weathering of silicate minerals,cation exchange processes,and human activities like mining andquarrying,are some of the main factors influencing groundwater chemistry.Principal component analysis revealed that groundwater chemistry is influenced by a combination of natural and anthropogenic sources.The APCs-MLR receptor model quantifies the factors that play important roles in groundwater salinization,including mineral dissolution and weathering(19.4%),localised Cd(16%),Ni(14.6%),Pb(12.8%),and Fe(11.4%)contamination from urbanisation while unidentified sources of pollution account for about 26.0%.The stable isotopes revealed groundwater is of meteoric origin and water-rock interaction the major mechanism for groundwater mineralization.The results of this research highlight the need of implementing an integrated strategy for managing and accessing groundwater quality.
基金the National Natural Science Foundation of China(12364044)Yunnan Major Scientific and Technological Projects(202202AG050004,202202AG050016,202302AQ370003)+1 种基金the International Joint Innovation Platform of Yunnan Province(202203AP140004)the Outstanding Youth Project of Yunnan Province Applied Basic Research Project(202401AV070012).
文摘Scintillator is a key material for the development of X-ray detectors,which has a promising application in medical imaging,security inspection and industrial non-injury detection.The majority of scintillators currently used in imaging are real-time imaging scintillators,which can cause ionization radiation damage to biological subjects or detection equipment during the imaging process and require complex,highly sensitive detection systems.Therefore,exploring stable,environmentally friendly scintillator materials that can achieve delayed imaging is of significance in the field of imaging.Herein,we devel-oped an X-ray time-lapse imaging scintillator,Sr_(2)Al_(6)O_(11):Dy^(3+)phosphor,which generates stable traps by X-ray irradiation,thus endowing it with excellent persistent luminescence and information storage properties(>42 d).Moreover,traps constructed by X-ray can be repeatedly refilled(>40 times)under UV light and carriers are released in theform of mechanical or thermal excitation when refilling is complete.By constructing the traps in the phosphor during X-ray excitation and using it for repetitive imaging,the detection limit is 74.78 nGy/s,and the spatial imaging resolution is as high as 16 lp/mm.This discovery providesa new idea for the development oftime-delayed X-ray scintillator.
