Slow-release phosphate materials were prepared by activating insoluble phosphate with organic acid to stabilize high concentrations of Cd and Zn in contaminated smelter soil.The results showed that oxalic acid(0.1 mol...Slow-release phosphate materials were prepared by activating insoluble phosphate with organic acid to stabilize high concentrations of Cd and Zn in contaminated smelter soil.The results showed that oxalic acid(0.1 mol/L)activated tricalcium phosphate(TO-0.1)provided the most efficient stabilization of Cd and Zn.After 30 d treatment,leaching concentrations of Cd and Zn in soil were decreased from 3.17 and 16.60 mg/L to 0.078 and 0.32 mg/L,respectively.The acid-soluble fractions of Cd and Zn were transformed into reducible,oxidizable,and residual fractions.Notably,As mobility in TO-0.1 treated soils did not increase.In addition,acid rain leaching and 150 d of natural aging revealed that the slow-release phosphate material provided long-term stability for the stabilization of Cd and Zn.This study verifies the potential application of slow-release phosphate materials for the remediation of heavy metal contaminated soil at smelting sites.展开更多
Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials ...Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials for ASIBs,Na_(3)V_(2)(PO_(4))_(3)(NVP) exhibits excellent structural stability and a high Na+diffusion coefficient,making it a promising option.However,the high solubility of vanadium-based materials in aqueous electrolytes engenders suboptimal cycling stability for Na_(3)V_(2)(PO_(4))_(3),constraining its application in ASIBs.Herein,the Cr-substituted Na_(3)V_(1.3)Cr_(0.7)(PO_(4))3@C(NV_(1.3)Cr_(0.7)P) cathode material was synthesized via a simple sol-gel method.It is found that Cr substitution reduces the cell parameters of NV_(1.3)Cr_(0.7)P,effectively reinforcing the crystal structure.Furthermore,NV_(1.3)Cr_(0.7)P alters the Na^(+)insertion/extraction mechanism,transforming the typical two-phase reaction between Na_(1)V_(2)(PO_(4))_(3)and Na_(3)V_(2)(PO_(4))3into continuous solid-solution reactions with stable intermediates.The Cr substitution diminishes the sodium-ion diffusion energy barrier in NV_(1.3)Cr_(0.7)P,leading to smoother Na+insertion and extraction processes.Consequently,NV_(1.3)Cr_(0.7)P exhibits impressive cycling stability,retaining 74.8% of its capacity after 5,000 cycles at a current density of 5 A g^(-1),along with an outstanding rate performance of 79,2% at 10 A g^(-1).This work elucidates the stable Na^(+)insertion/extraction processes in Cr-substituted NV_(1.3)Cr_(0.7)P,offering insights into the application of vanadium-based materials in aqueous sodium-ion batteries.展开更多
Valtrate is the main drug quality control for the qualitative and quantitative analysis of Valerian medicines in the Chinese Pharmacopoeia 2010. However, valtrate is unstable under some conditions. We, for the first t...Valtrate is the main drug quality control for the qualitative and quantitative analysis of Valerian medicines in the Chinese Pharmacopoeia 2010. However, valtrate is unstable under some conditions. We, for the first time, systemically evaluated the stability of two bath reference standards （RS） by high performance liquid chromatography coupled with a triple quadrupole mass spectrometer （HPLC-MS/MS）. The forced degradations of valtrate were performed to evaluate its optimal storage, transportation and experiment conditions according to ICH guideline. The developed HPLC method was validated to determine the degradation products. Valtrate RS was sensitive to alkaline and thermal conditions, but it was relatively stable under acidic, oxidation and photolysis conditions. A total of nine degradation components were identified under alkaline hydrolysis （N1-N4） and thermal degradation （B1-B5）. The information obtained in this work would be valuable to minimize the decomposition of valtrate during the processes of preparation, storage, distribution and utilization. It was highly suggested to store valtrate with a single dose packing in brown closed ampoule at -20℃. Under the above-mentioned storage condition, valtrate could be stable for up to 3 years.展开更多
The presence of defects and detrimental reactions at NiO_(x)/perovskite interface extremely limit the efficiency performance and long-term stability of the perovskite solar cells(PSCs) based on NiO_(x).Herein,an amphi...The presence of defects and detrimental reactions at NiO_(x)/perovskite interface extremely limit the efficiency performance and long-term stability of the perovskite solar cells(PSCs) based on NiO_(x).Herein,an amphipathic molecule Triton X100(Triton) is modified on the NiO_(x)surface.The hydrophilic chain of Triton as a Lewis base additive can coordinate with the Ni3+on the NiO_(x)surface which can passivate the interfacial defects and hinder the detrimental reactions at the NiO_(x)/perovskite interface.Additionally,the hydrophobic chain of Triton protrudes from the NiO_(x)surface to prevent moisture from penetrating into the NiO_(x)/perovskite interface.Consequently,the NiO_(x)/Triton-based devices(MAPbI3as absorbing layer) show superior moisture and thermal stability,retaining 88.4% and 64.3% of the initial power conversion efficiency after storage in air(40%-50% relative humidity(RH)) at 25 ℃ for 1070 h and in N2at 85℃ for 800 h,respectively.Moreover,the efficiency increases from 17.59% to 19.89% because of the passivation defect and enhanced hole-extraction capability.Besides,the NiO_(x)/Triton-based PSCs with Cs_(0.05)(MA_(0.15)FA_(0.85))_(0.95)Pb(I_(0.85)Br_(0.15))3perovskite as the light-absorbing layer also exhibits better moisture and thermal stability compared to the control devices,indicating the viability of our strategies.Of particular note,a champion PCE of 22.35% and 20.46% was achieved for small-area(0.1 cm^(2)) and large-area(1.2 cm^(2)) NiO_(x)/Triton-based devices,respectively.展开更多
Callovo-Oxfordian(COx)claystone has been considered as a potential host rock for geological radioactive waste disposal in France(Cigéo project).During the exploitation phase(100 years),the stability of drifts(e.g...Callovo-Oxfordian(COx)claystone has been considered as a potential host rock for geological radioactive waste disposal in France(Cigéo project).During the exploitation phase(100 years),the stability of drifts(e.g.galleries/alveoli)within the disposal is assured by the liner,which includes two layers:concrete arch segment and compressible material.The latter exhibits a significant deformation capacity(about 50%)under low stress(<3 MPa).Although the response of these underground structures can be governed by complex thermo-hydro-mechanical coupling,the creep behavior of COx claystone has been considered as the main factor controlling the increase of stress state in the concrete liner and hence the long-term stability of drifts.Therefore,by focusing only on the purely mechanical behavior,this study aims at investigating the uncertainty effect of the COx claystone time-dependent properties on the stability of an alveolus of Cigéo during the exploitation period.To describe the creep behavior of COx claystone,we use Lemaitre’s viscoplastic model with three parameters whose uncertainties are identified from laboratory creep tests.For the reliability analysis,an extension of a well-known Kriging metamodeling technique is proposed to assess the exceedance probability of acceptable stress in the concrete liner of the alveolus.The open-source code Code_Aster is chosen for the direct numerical evaluations of the performance function.The Kriging-based reliability analysis elucidates the effect of the uncertainty of COx claystone on the long-term stability of the concrete liner.Moreover,the role of the compressible material layer between the concrete liner and the host rock is also highlighted.展开更多
All-inorganic CsPbI_(2)Br perovskite solar cells(PSCs)have received extensive research interests recently.Nevertheless,their low efficiency and poor long-term stability are still obstacles for further commercial appli...All-inorganic CsPbI_(2)Br perovskite solar cells(PSCs)have received extensive research interests recently.Nevertheless,their low efficiency and poor long-term stability are still obstacles for further commercial application.Herein,we demonstrate that high efficiency and exceptional long-term stability are realized by incorporating gadolinium(III)chloride(GdCl_(3))into the CsPbI_(2)Br perovskite film.The incorporation of GdCl_(3) enhances the Goldschmidt tolerance factor of CsPbI_(2)Br perovskite,yielding a dense perovskite film with small grains,thus the a-phase CsPbI_(2)Br is remarkably stabilized.Additionally,it is found that the GdCl_(3)-incorporated perovskite film achieves suppressed charge recombination and appropriate energy level alignment compared with the pristine CsPbI_(2)Br film.The noticeable increment in efficiency from14.01%(control PSC)to 16.24%is achieved for GdCl_(3)-incorporated PSC.Moreover,the nonencapsulated GdCl_(3)-incorporated PSC exhibits excellent environmental and thermal stability,remaining over 91%or90%of the original efficiency after 1200 h aging at 40%relative humidity or 480 h heating at 85℃ in nitrogen glove box respectively.The encapsulated GdCl_(3)-incorporated PSC presents an improved operational stability with over 88%of initial efficiency under maximum power point(MPP)tracking at 45℃ for1000 h.This work presents an effective ion-incorporation approach for boosting efficiency and long-term stability of all-inorganic PSCs.展开更多
Long-term stability of large-span caverns is a challenging issue for design and construction of underground rock engineering.The Heidong cavern group consisting of 21 caverns was constructed about 1400 years ago for q...Long-term stability of large-span caverns is a challenging issue for design and construction of underground rock engineering.The Heidong cavern group consisting of 21 caverns was constructed about 1400 years ago for quarrying in massive Cretaceous tuff.The cavern No.5 of the Heidong cavern group is characterized by an unsupported span up to 92 m,with the overburden thickness of only 3-25 m.To analyze its long-term stability,a detailed investigation was conducted to obtain its geometry and rock mass characteristics,and to monitor surrounding rock displacements.Based on field survey and laboratory tests,numerical simulations were performed using the finite difference code FLAC;.The analysis results revealed that for the long-term stability of the cavern No.5,some major factors should be carefully considered,such as cavern excavation method in hard massive rocks,site investigation using trial pits,tools like short iron chisel and hammer for manual excavation,geometric dome roof,and waste rocks within abutment or on the floor.The highlights of the technologies obtained from this large-scale ancient underground project can provide reference for other similar project excavations in practice.展开更多
In this work,we developed the PM6:Y6-based inverted structure organic photovoltaic(i-OPV)with improved power conversion efficiency(PCE)and long-term stability by resolving the origins of the performance deterioration....In this work,we developed the PM6:Y6-based inverted structure organic photovoltaic(i-OPV)with improved power conversion efficiency(PCE)and long-term stability by resolving the origins of the performance deterioration.The deep defects between the metal oxide-based electron transport layer and bulk-heterojunction photoactive layer interface were responsible for suboptimal PCE and facilitated degradation of devices.While the density of deep traps is increased during the storage of i-OPV,the penetrative oxygen-containing defects additionally generated shallow traps below the band-edge of Y6,causing an additional loss in the open-circuit voltage.The suppression of interfacial defects by chemical modification effectively improved the PCE and long-term stability of i-OPV.The modified i-OPV(mi-OPV)achieved a PCE of 17.42%,which is the highest value among the reported PM6:Y6-based i-OPV devices.Moreover,long-term stability was significantly improved:~90%and~80%retention of its initial PCE after 1200 h of air storage and illumination,respectively.展开更多
Based on the analysis of the basic characteristics for the gob site in Northern Shaanxi Province and the room and pillar mining way about coal mine, the variety rule of the coal beds below the site was studied by the ...Based on the analysis of the basic characteristics for the gob site in Northern Shaanxi Province and the room and pillar mining way about coal mine, the variety rule of the coal beds below the site was studied by the using of FEM during the process of coal mining. The statuses of the stresses and strains and the varieties of the plastic area were simulated in the whole rock and coal pillars. The characters of stresses and deformation of the gob area of the coalmine were analyzed and evaluated after the site built in weathering. Moreover, the long-term stability of the gob area was predicted. As a result, the deformation of the gob area under the site is not been finished, and there is the danger that the gob site will collapsing as a whole; therefore, relative measures must be taken.展开更多
The subject of the present paper is to prove that the recently introduced conjecture of boundedness puts a ban over the view of stability as asymptotic property. This result comes in sharp contrast with the prescripti...The subject of the present paper is to prove that the recently introduced conjecture of boundedness puts a ban over the view of stability as asymptotic property. This result comes in sharp contrast with the prescription of the traditional thermodynamics and statistical physics which consider the existence of equilibrium as asymptotic property of all systems. The difference commences from the use of infinitesimal calculus as the basic implement for modelling by the latter while the primary premise of the conjecture of boundedness is sustaining the energy/matter/information permanently bounded and finite. The latter property overrules the infinitesimal calculus as the major implement of modelling because, among all, it is proven that the traditional one suffers unsoluble difficulties.展开更多
It is well known that calcium arsenates may not be a good choice for arsenic removal and immobilization in hydrometallurgical practices.However,they are still produced at some plants in the world due to various reason...It is well known that calcium arsenates may not be a good choice for arsenic removal and immobilization in hydrometallurgical practices.However,they are still produced at some plants in the world due to various reasons.Furthermore,calcium arsenates can also naturally precipitate under some specific environments.However,the transformation process of poorly crystalline calcium arsenates(PCCA)and the stability of these samples under atmospheric CO2 are not yet well understood.This work investigated the transformation process of PCCA produced by using different neutralization reagents(CaO vs.NaOH)with various Ca/As molar ratios at pH 7-12 in the presence of atmospheric CO2.After aging at room temperature for a period of time,for samples neutralized with NaOH and precipitated at pH 10 and 12,release of arsenic back into the liquid phase occurred.In contrast,for the samples precipitated at pH 8,the aqueous concentration of arsenic was observed to decrease.XRD,Raman,and SEM results suggested that the formation of various types of crystalline calcium carbonates and/or calcium arsenates controls the arsenic behavior.Moreover,the application of lime may enhance the stability of the generated PCCA.However,no matter what neutralization reagent is used,the stability of the generated PCCA is still of concern.展开更多
We describe the long-term stability and mean climatology of oceanic circulations simulated by version 2 of the Flexible Global Ocean-Atmosphere-Land System model （FGOALS-s2）. Driven by pre-industrial forcing, the in...We describe the long-term stability and mean climatology of oceanic circulations simulated by version 2 of the Flexible Global Ocean-Atmosphere-Land System model （FGOALS-s2）. Driven by pre-industrial forcing, the integration of FGOALS-s2 was found to have remained stable, with no obvious climate drift over 600 model years. The linear trends of sea SST and sea surface salinity （SSS） were -0.04℃ （100 yr）-1 and 0.01 psu （100 yr）-1, respectively. The simulations of oceanic temperatures, wind-driven circulation and thermohaline circulation in FGOALS-s2 were found to be comparable with observations, and have been substantially improved over previous FGOALS-s versions （1.0 and 1.1）. However, significant SST biases （exceeding 3℃） were found around strong western boundary currents, in the East China Sea, the Sea of Japan and the Barents Sea. Along the eastern coasts in the Pacific and Atlantic Ocean, a warm bias （〉3℃） was mainly due to overestimation of net surface shortwave radiation and weak oceanic upwelling. The difference of SST biases in the North Atlantic and Pacific was partly due to the errors of meridional heat transport. For SSS, biases exceeding 1.5 psu were located in the Arctic Ocean and around the Gulf Stream. In the tropics, freshwater biases dominated and were mainly caused by the excess of precipitation. Regarding the vertical dimension, the maximal biases of temperature and salinity were located north of 65°N at depths of greater than 600 m, and their values exceeded 4℃ and 2 psu, respectively.展开更多
Spherical Ag nanoparticles(AgNPs) with a diameter of 20 nm or smaller were biologically synthesized using algae Parachlorella kessleri. The effect of storage conditions on the long-term stability of AgNPs was investig...Spherical Ag nanoparticles(AgNPs) with a diameter of 20 nm or smaller were biologically synthesized using algae Parachlorella kessleri. The effect of storage conditions on the long-term stability of AgNPs was investigated. UV/Vis spectrophotometry, transmission electron microscopy, and dynamic light scattering measurements revealed that the long-term stability of AgNPs was influenced by light and temperature conditions. The most significant loss of stability was observed for the AgNPs stored in daylight at room temperature. The AgNPs stored under these conditions began to lose their stability after approximately 30 d; after 100 d, a substantial amount of agglomerated particles settled to the bottom of the Erlenmeyer flask. The AgNPs stored in the dark at room temperature exhibited better long-term stability. Weak particle agglomeration began at approximately the 100 th day. The AgNPs stored in the dark at about 5℃ exhibited the best long-term stability; the AgNPs stored under such conditions remained spherical, with a narrow size distribution, and stable(no agglomeration) even after 6 months. Zeta-potential measurements confirmed better dispersity and stability of AgNPs stored under these conditions.展开更多
A lock solution composed of gentamicin sulfate(5 mg/mL) and ethylenediaminetetraacetic acid disodium salt(EDTA-Na2, 30 mg/mL) could fully eradicate in vivo bacterial biofilms in totally implantable venous access ports...A lock solution composed of gentamicin sulfate(5 mg/mL) and ethylenediaminetetraacetic acid disodium salt(EDTA-Na2, 30 mg/mL) could fully eradicate in vivo bacterial biofilms in totally implantable venous access ports(TIVAP). In this study, fabrication, conditioning and sterilization processes of antimicrobial lock solution(ALS) were detailed and completed by a stability study. Stability of ALS was conducted for12 months in vial(25 °C 7 2 °C, 60% 7 5% relative humidity(RH), and at 40 °C 7 2 °C, RH 75% 7 5%)and for 24 h and 72 h in TIVAP(40 °C 7 2 °C, RH 75% 7 5%). A stability indicating HPLC assay with UV detection for simultaneous quantification of gentamicin sulfate and EDTA-Na2 was developed. ALS was assayed by ion-pairing high performance liquid chromatography(HPLC) needing gentamicin derivatization, EDTA-Na2 metallocomplexation of samples and gradient mobile phase. HPLC methods to separate four gentamicin components and EDTA-Na2 were validated. Efficiency of sterility procedure and conditioning of ALS was confirmed by bacterial endotoxins and sterility tests. Physicochemical stability of ALS was determined by visual inspection, osmolality, pH, and sub-visible particle counting. Results confirmed that the stability of ALS in vials was maintained for 12 months and 24 h and 72 h in TIVAP.展开更多
Numerical analysis of the optimal supporting time and long-term stability index of the surrounding rocks in the underground plant of Xiangjiaba hydro-power station was carried out based on the rheological theory. Firs...Numerical analysis of the optimal supporting time and long-term stability index of the surrounding rocks in the underground plant of Xiangjiaba hydro-power station was carried out based on the rheological theory. Firstly,the mechanical parameters of each rock group were identified from the experimental data; secondly,the rheological calculation and analysis for the cavern in stepped excavation without supporting were made; finally,the optimal time for supporting at the characteristic point in a typical section was obtained while the creep rate and displacement after each excavation step has satisfied the criterion of the optimal supporting time. Excavation was repeated when the optimal time for supporting was identified,and the long-term stability creep time and the maximum creep deformation of the characteristic point were determined in accordance with the criterion of long-term stability index. It is shown that the optimal supporting time of the characteristic point in the underground plant of Xiangjiaba hydro-power station is 5-8 d,the long-term stability time of the typical section is 126 d,and the corresponding largest creep deformation is 24.30 mm. While the cavern is supported,the cavern deformation is significantly reduced and the stress states of the surrounding rock masses are remarkably improved.展开更多
Phenethylamine（PEA） was successfully introduced into hole-conductor-free, fully printable mesoscopic MAPbI3 perovskite solar cells（MPSCs） with a carbon electrode by mixing phenethylammonium iodide with MAPbI3 pero...Phenethylamine（PEA） was successfully introduced into hole-conductor-free, fully printable mesoscopic MAPbI3 perovskite solar cells（MPSCs） with a carbon electrode by mixing phenethylammonium iodide with MAPbI3 perovskite solution. PEA-MAPbI3 films show better pore filling into TiO2 scaffold that forms better contact, and induce longer exciton lifetime and higher quantum efficiency of photoinduced charge separation. As a result, the power conversion efficiency of PEA-MAPbI3 MPSCs is 37% higher than that of MAPbI3 MPSCs. And PEA-MAPbI3 MPSCs show excellent long-term stability that could keep 90% of origin power conversion efficiency for over 80 days in the air.展开更多
Spherical Ag nanoparticles（AgNPs） were biologically synthesized using four different extracts prepared from Parachlorella kessleri algae cultivated for 1, 2, 3 and 4 weeks. The influence of algae life cycle on AgNPs...Spherical Ag nanoparticles（AgNPs） were biologically synthesized using four different extracts prepared from Parachlorella kessleri algae cultivated for 1, 2, 3 and 4 weeks. The influence of algae life cycle on AgNPs formation and effect of different storage conditions on AgNPs long-term stability were investigated. The age of algae influenced the rate of AgNPs synthesis and amount of AgNPs in solution. The age of algae did not influence the AgNPs long-term stability. UV–vis and TEM observation revealed that long-term stability of AgNPs can be influenced by storage temperatures, and low temperature positively influences the AgNPs stability. AgNPs stored at dark and at temperature of ~5 °C showed the best long-term stability regardless of the culture age. Such AgNPs remained spherical, fine（5-20 nm） and stable（no agglomeration） even after 6 months.展开更多
Long-term stability of large span caverns is earnest but poorly understood in preservation of cultural relics.The life span of huge caverns is difficult to extrapolate from short period of monitoring or laboratory tes...Long-term stability of large span caverns is earnest but poorly understood in preservation of cultural relics.The life span of huge caverns is difficult to extrapolate from short period of monitoring or laboratory testing.A huge ancient quarry with 21 caverns whose original status is well kept over 1400 years was found in Tiantai County of South China.One of the caverns has an 81 m span which is far beyond the 50 m expectation on current knowledge.The tension at the core of long stability is the excavation speed versus deliberation.Here we show a unique technique of Digging Holes for Quarrying Vertical Flagstone(DQF)invented by ancestors to ensure the safety,which is much smarter compared to blasting and casting technique that commonly used after the Industrial Revolution.展开更多
基金supported by the Natural Science Foundation of Hunan Province,China(No.2024JJ1012)the Postgraduate Innovative Project of Central South University,China(No.2023ZZTS0459)the National Key Research and Development Program of China(No.2019YFC1803605)。
文摘Slow-release phosphate materials were prepared by activating insoluble phosphate with organic acid to stabilize high concentrations of Cd and Zn in contaminated smelter soil.The results showed that oxalic acid(0.1 mol/L)activated tricalcium phosphate(TO-0.1)provided the most efficient stabilization of Cd and Zn.After 30 d treatment,leaching concentrations of Cd and Zn in soil were decreased from 3.17 and 16.60 mg/L to 0.078 and 0.32 mg/L,respectively.The acid-soluble fractions of Cd and Zn were transformed into reducible,oxidizable,and residual fractions.Notably,As mobility in TO-0.1 treated soils did not increase.In addition,acid rain leaching and 150 d of natural aging revealed that the slow-release phosphate material provided long-term stability for the stabilization of Cd and Zn.This study verifies the potential application of slow-release phosphate materials for the remediation of heavy metal contaminated soil at smelting sites.
基金financially supported by the Scientific and Technological Plan Project of Guizhou Province ([2024]054)Additional support came from the Industry and Education Combination Innovation Platform of Intelligent Manufacturing and Graduate Joint Training Base at Guizhou University (2020-520000-83-01324061)the Guizhou Engineering Research Center for Smart Services (2203-520102-04-04-298868)。
文摘Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials for ASIBs,Na_(3)V_(2)(PO_(4))_(3)(NVP) exhibits excellent structural stability and a high Na+diffusion coefficient,making it a promising option.However,the high solubility of vanadium-based materials in aqueous electrolytes engenders suboptimal cycling stability for Na_(3)V_(2)(PO_(4))_(3),constraining its application in ASIBs.Herein,the Cr-substituted Na_(3)V_(1.3)Cr_(0.7)(PO_(4))3@C(NV_(1.3)Cr_(0.7)P) cathode material was synthesized via a simple sol-gel method.It is found that Cr substitution reduces the cell parameters of NV_(1.3)Cr_(0.7)P,effectively reinforcing the crystal structure.Furthermore,NV_(1.3)Cr_(0.7)P alters the Na^(+)insertion/extraction mechanism,transforming the typical two-phase reaction between Na_(1)V_(2)(PO_(4))_(3)and Na_(3)V_(2)(PO_(4))3into continuous solid-solution reactions with stable intermediates.The Cr substitution diminishes the sodium-ion diffusion energy barrier in NV_(1.3)Cr_(0.7)P,leading to smoother Na+insertion and extraction processes.Consequently,NV_(1.3)Cr_(0.7)P exhibits impressive cycling stability,retaining 74.8% of its capacity after 5,000 cycles at a current density of 5 A g^(-1),along with an outstanding rate performance of 79,2% at 10 A g^(-1).This work elucidates the stable Na^(+)insertion/extraction processes in Cr-substituted NV_(1.3)Cr_(0.7)P,offering insights into the application of vanadium-based materials in aqueous sodium-ion batteries.
基金Special Funds of the National Natural Science Foundation of China on"Major New Drugs Innovation and Development"(Grant No.2014ZX09304307-002)
文摘Valtrate is the main drug quality control for the qualitative and quantitative analysis of Valerian medicines in the Chinese Pharmacopoeia 2010. However, valtrate is unstable under some conditions. We, for the first time, systemically evaluated the stability of two bath reference standards （RS） by high performance liquid chromatography coupled with a triple quadrupole mass spectrometer （HPLC-MS/MS）. The forced degradations of valtrate were performed to evaluate its optimal storage, transportation and experiment conditions according to ICH guideline. The developed HPLC method was validated to determine the degradation products. Valtrate RS was sensitive to alkaline and thermal conditions, but it was relatively stable under acidic, oxidation and photolysis conditions. A total of nine degradation components were identified under alkaline hydrolysis （N1-N4） and thermal degradation （B1-B5）. The information obtained in this work would be valuable to minimize the decomposition of valtrate during the processes of preparation, storage, distribution and utilization. It was highly suggested to store valtrate with a single dose packing in brown closed ampoule at -20℃. Under the above-mentioned storage condition, valtrate could be stable for up to 3 years.
基金supported by the National Key Research and Development Program of China(2018YFA0208701)the National Natural Science Foundation of China(21773308)+7 种基金the Research Funds of Renmin University of China(2017030013,201903020 and 20XNH059)the Fundamental Research Funds for Central Universities(China)supported by the Solar Energy Research Institute of Singapore(SERIS) at the National University of Singapore(NUS)supported by NUSthe National Research Foundation Singapore(NRF)the Energy Market Authority of Singapore(EMA)the Singapore Economic Development Board(EDB)the financial support from the China Scholarship Council(CSC) funding。
文摘The presence of defects and detrimental reactions at NiO_(x)/perovskite interface extremely limit the efficiency performance and long-term stability of the perovskite solar cells(PSCs) based on NiO_(x).Herein,an amphipathic molecule Triton X100(Triton) is modified on the NiO_(x)surface.The hydrophilic chain of Triton as a Lewis base additive can coordinate with the Ni3+on the NiO_(x)surface which can passivate the interfacial defects and hinder the detrimental reactions at the NiO_(x)/perovskite interface.Additionally,the hydrophobic chain of Triton protrudes from the NiO_(x)surface to prevent moisture from penetrating into the NiO_(x)/perovskite interface.Consequently,the NiO_(x)/Triton-based devices(MAPbI3as absorbing layer) show superior moisture and thermal stability,retaining 88.4% and 64.3% of the initial power conversion efficiency after storage in air(40%-50% relative humidity(RH)) at 25 ℃ for 1070 h and in N2at 85℃ for 800 h,respectively.Moreover,the efficiency increases from 17.59% to 19.89% because of the passivation defect and enhanced hole-extraction capability.Besides,the NiO_(x)/Triton-based PSCs with Cs_(0.05)(MA_(0.15)FA_(0.85))_(0.95)Pb(I_(0.85)Br_(0.15))3perovskite as the light-absorbing layer also exhibits better moisture and thermal stability compared to the control devices,indicating the viability of our strategies.Of particular note,a champion PCE of 22.35% and 20.46% was achieved for small-area(0.1 cm^(2)) and large-area(1.2 cm^(2)) NiO_(x)/Triton-based devices,respectively.
文摘Callovo-Oxfordian(COx)claystone has been considered as a potential host rock for geological radioactive waste disposal in France(Cigéo project).During the exploitation phase(100 years),the stability of drifts(e.g.galleries/alveoli)within the disposal is assured by the liner,which includes two layers:concrete arch segment and compressible material.The latter exhibits a significant deformation capacity(about 50%)under low stress(<3 MPa).Although the response of these underground structures can be governed by complex thermo-hydro-mechanical coupling,the creep behavior of COx claystone has been considered as the main factor controlling the increase of stress state in the concrete liner and hence the long-term stability of drifts.Therefore,by focusing only on the purely mechanical behavior,this study aims at investigating the uncertainty effect of the COx claystone time-dependent properties on the stability of an alveolus of Cigéo during the exploitation period.To describe the creep behavior of COx claystone,we use Lemaitre’s viscoplastic model with three parameters whose uncertainties are identified from laboratory creep tests.For the reliability analysis,an extension of a well-known Kriging metamodeling technique is proposed to assess the exceedance probability of acceptable stress in the concrete liner of the alveolus.The open-source code Code_Aster is chosen for the direct numerical evaluations of the performance function.The Kriging-based reliability analysis elucidates the effect of the uncertainty of COx claystone on the long-term stability of the concrete liner.Moreover,the role of the compressible material layer between the concrete liner and the host rock is also highlighted.
基金supported by the National Natural Science Foundation of China(52172237,52072228)the Shaanxi International Cooperational Project(2020KWZ-018)+1 种基金the Research Fund of the State Key Laboratory of Solidification Processing(NPU),China(Grant No.2021-QZ-02)the Fundamental Research Funds for the Central Universities(3102019JC005)。
文摘All-inorganic CsPbI_(2)Br perovskite solar cells(PSCs)have received extensive research interests recently.Nevertheless,their low efficiency and poor long-term stability are still obstacles for further commercial application.Herein,we demonstrate that high efficiency and exceptional long-term stability are realized by incorporating gadolinium(III)chloride(GdCl_(3))into the CsPbI_(2)Br perovskite film.The incorporation of GdCl_(3) enhances the Goldschmidt tolerance factor of CsPbI_(2)Br perovskite,yielding a dense perovskite film with small grains,thus the a-phase CsPbI_(2)Br is remarkably stabilized.Additionally,it is found that the GdCl_(3)-incorporated perovskite film achieves suppressed charge recombination and appropriate energy level alignment compared with the pristine CsPbI_(2)Br film.The noticeable increment in efficiency from14.01%(control PSC)to 16.24%is achieved for GdCl_(3)-incorporated PSC.Moreover,the nonencapsulated GdCl_(3)-incorporated PSC exhibits excellent environmental and thermal stability,remaining over 91%or90%of the original efficiency after 1200 h aging at 40%relative humidity or 480 h heating at 85℃ in nitrogen glove box respectively.The encapsulated GdCl_(3)-incorporated PSC presents an improved operational stability with over 88%of initial efficiency under maximum power point(MPP)tracking at 45℃ for1000 h.This work presents an effective ion-incorporation approach for boosting efficiency and long-term stability of all-inorganic PSCs.
基金financial support by the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology(Grant No.SKLGP2011K007)the Key Research Program of the Chinese Academy of Sciences(KZZD-EW05-02)the National Natural Science Foundation of China (Nos.41372324,40972198 and 41172269)
文摘Long-term stability of large-span caverns is a challenging issue for design and construction of underground rock engineering.The Heidong cavern group consisting of 21 caverns was constructed about 1400 years ago for quarrying in massive Cretaceous tuff.The cavern No.5 of the Heidong cavern group is characterized by an unsupported span up to 92 m,with the overburden thickness of only 3-25 m.To analyze its long-term stability,a detailed investigation was conducted to obtain its geometry and rock mass characteristics,and to monitor surrounding rock displacements.Based on field survey and laboratory tests,numerical simulations were performed using the finite difference code FLAC;.The analysis results revealed that for the long-term stability of the cavern No.5,some major factors should be carefully considered,such as cavern excavation method in hard massive rocks,site investigation using trial pits,tools like short iron chisel and hammer for manual excavation,geometric dome roof,and waste rocks within abutment or on the floor.The highlights of the technologies obtained from this large-scale ancient underground project can provide reference for other similar project excavations in practice.
基金supported by a National Research Foundation of Korea(grant#:2020R1A2C1003929,2019R1A6A1A11053838,2020M1A2A2080746,2021M2E8A1044198,2016R1A5A1012966,2021M3H4A1A03051379).
文摘In this work,we developed the PM6:Y6-based inverted structure organic photovoltaic(i-OPV)with improved power conversion efficiency(PCE)and long-term stability by resolving the origins of the performance deterioration.The deep defects between the metal oxide-based electron transport layer and bulk-heterojunction photoactive layer interface were responsible for suboptimal PCE and facilitated degradation of devices.While the density of deep traps is increased during the storage of i-OPV,the penetrative oxygen-containing defects additionally generated shallow traps below the band-edge of Y6,causing an additional loss in the open-circuit voltage.The suppression of interfacial defects by chemical modification effectively improved the PCE and long-term stability of i-OPV.The modified i-OPV(mi-OPV)achieved a PCE of 17.42%,which is the highest value among the reported PM6:Y6-based i-OPV devices.Moreover,long-term stability was significantly improved:~90%and~80%retention of its initial PCE after 1200 h of air storage and illumination,respectively.
文摘Based on the analysis of the basic characteristics for the gob site in Northern Shaanxi Province and the room and pillar mining way about coal mine, the variety rule of the coal beds below the site was studied by the using of FEM during the process of coal mining. The statuses of the stresses and strains and the varieties of the plastic area were simulated in the whole rock and coal pillars. The characters of stresses and deformation of the gob area of the coalmine were analyzed and evaluated after the site built in weathering. Moreover, the long-term stability of the gob area was predicted. As a result, the deformation of the gob area under the site is not been finished, and there is the danger that the gob site will collapsing as a whole; therefore, relative measures must be taken.
文摘The subject of the present paper is to prove that the recently introduced conjecture of boundedness puts a ban over the view of stability as asymptotic property. This result comes in sharp contrast with the prescription of the traditional thermodynamics and statistical physics which consider the existence of equilibrium as asymptotic property of all systems. The difference commences from the use of infinitesimal calculus as the basic implement for modelling by the latter while the primary premise of the conjecture of boundedness is sustaining the energy/matter/information permanently bounded and finite. The latter property overrules the infinitesimal calculus as the major implement of modelling because, among all, it is proven that the traditional one suffers unsoluble difficulties.
基金supported by the National Natural Science Foundation of China (Nos. 41530643, 41673130 and 41877393)the National Key R&D Program of China (No. 2017YFD0800301)the Chinese Academy of Sciences (No. QYZDJ-SSW-DQC038)
文摘It is well known that calcium arsenates may not be a good choice for arsenic removal and immobilization in hydrometallurgical practices.However,they are still produced at some plants in the world due to various reasons.Furthermore,calcium arsenates can also naturally precipitate under some specific environments.However,the transformation process of poorly crystalline calcium arsenates(PCCA)and the stability of these samples under atmospheric CO2 are not yet well understood.This work investigated the transformation process of PCCA produced by using different neutralization reagents(CaO vs.NaOH)with various Ca/As molar ratios at pH 7-12 in the presence of atmospheric CO2.After aging at room temperature for a period of time,for samples neutralized with NaOH and precipitated at pH 10 and 12,release of arsenic back into the liquid phase occurred.In contrast,for the samples precipitated at pH 8,the aqueous concentration of arsenic was observed to decrease.XRD,Raman,and SEM results suggested that the formation of various types of crystalline calcium carbonates and/or calcium arsenates controls the arsenic behavior.Moreover,the application of lime may enhance the stability of the generated PCCA.However,no matter what neutralization reagent is used,the stability of the generated PCCA is still of concern.
基金supported by the National Key Program for Developing Basic Sciences(GrantNos. 2010CB950502)the "Strategic Priority Research Program-Climate Change:Carbon Budget and Related Issues" of the Chinese Academy of Sciences (Grant No.XDA05110302)+1 种基金the National Natural Science Foundation of China(Grant Nos. 40906012 and 41023002)National High Technology Research and Development Program of China(Grant No. 2010AA012303)
文摘We describe the long-term stability and mean climatology of oceanic circulations simulated by version 2 of the Flexible Global Ocean-Atmosphere-Land System model （FGOALS-s2）. Driven by pre-industrial forcing, the integration of FGOALS-s2 was found to have remained stable, with no obvious climate drift over 600 model years. The linear trends of sea SST and sea surface salinity （SSS） were -0.04℃ （100 yr）-1 and 0.01 psu （100 yr）-1, respectively. The simulations of oceanic temperatures, wind-driven circulation and thermohaline circulation in FGOALS-s2 were found to be comparable with observations, and have been substantially improved over previous FGOALS-s versions （1.0 and 1.1）. However, significant SST biases （exceeding 3℃） were found around strong western boundary currents, in the East China Sea, the Sea of Japan and the Barents Sea. Along the eastern coasts in the Pacific and Atlantic Ocean, a warm bias （〉3℃） was mainly due to overestimation of net surface shortwave radiation and weak oceanic upwelling. The difference of SST biases in the North Atlantic and Pacific was partly due to the errors of meridional heat transport. For SSS, biases exceeding 1.5 psu were located in the Arctic Ocean and around the Gulf Stream. In the tropics, freshwater biases dominated and were mainly caused by the excess of precipitation. Regarding the vertical dimension, the maximal biases of temperature and salinity were located north of 65°N at depths of greater than 600 m, and their values exceeded 4℃ and 2 psu, respectively.
基金supported by Slovak Grant Agency (VEGA 1/0197/15)the Ministry of Education, Youth and Sport of the Czech Republic within the scope of project No.LO1207 of the program NPU1
文摘Spherical Ag nanoparticles(AgNPs) with a diameter of 20 nm or smaller were biologically synthesized using algae Parachlorella kessleri. The effect of storage conditions on the long-term stability of AgNPs was investigated. UV/Vis spectrophotometry, transmission electron microscopy, and dynamic light scattering measurements revealed that the long-term stability of AgNPs was influenced by light and temperature conditions. The most significant loss of stability was observed for the AgNPs stored in daylight at room temperature. The AgNPs stored under these conditions began to lose their stability after approximately 30 d; after 100 d, a substantial amount of agglomerated particles settled to the bottom of the Erlenmeyer flask. The AgNPs stored in the dark at room temperature exhibited better long-term stability. Weak particle agglomeration began at approximately the 100 th day. The AgNPs stored in the dark at about 5℃ exhibited the best long-term stability; the AgNPs stored under such conditions remained spherical, with a narrow size distribution, and stable(no agglomeration) even after 6 months. Zeta-potential measurements confirmed better dispersity and stability of AgNPs stored under these conditions.
基金supported by Centre de Recherche Translationnelle de I'Institut Pasteur, grant Number S- PI15007-02Asupported by the French Government's Investissement d'Avenir program:Laboratoire d'Excellence ‘Integrative Biology of Emerging Infectious Diseases’ (grant no. ANR-10-LABX62-IBEID.)+1 种基金the Fondation pour la Recherche Médicale (grant no. DEQ. 20140329508)the Center for Translational Science of the Institut Pasteur (S-PI15007-02A)
文摘A lock solution composed of gentamicin sulfate(5 mg/mL) and ethylenediaminetetraacetic acid disodium salt(EDTA-Na2, 30 mg/mL) could fully eradicate in vivo bacterial biofilms in totally implantable venous access ports(TIVAP). In this study, fabrication, conditioning and sterilization processes of antimicrobial lock solution(ALS) were detailed and completed by a stability study. Stability of ALS was conducted for12 months in vial(25 °C 7 2 °C, 60% 7 5% relative humidity(RH), and at 40 °C 7 2 °C, RH 75% 7 5%)and for 24 h and 72 h in TIVAP(40 °C 7 2 °C, RH 75% 7 5%). A stability indicating HPLC assay with UV detection for simultaneous quantification of gentamicin sulfate and EDTA-Na2 was developed. ALS was assayed by ion-pairing high performance liquid chromatography(HPLC) needing gentamicin derivatization, EDTA-Na2 metallocomplexation of samples and gradient mobile phase. HPLC methods to separate four gentamicin components and EDTA-Na2 were validated. Efficiency of sterility procedure and conditioning of ALS was confirmed by bacterial endotoxins and sterility tests. Physicochemical stability of ALS was determined by visual inspection, osmolality, pH, and sub-visible particle counting. Results confirmed that the stability of ALS in vials was maintained for 12 months and 24 h and 72 h in TIVAP.
基金Projects(50911130366, 50979030) supported by the National Natural Science Foundation of ChinaProject(2008BAB29B01) supported by the National Key Technology R&D Program of China
文摘Numerical analysis of the optimal supporting time and long-term stability index of the surrounding rocks in the underground plant of Xiangjiaba hydro-power station was carried out based on the rheological theory. Firstly,the mechanical parameters of each rock group were identified from the experimental data; secondly,the rheological calculation and analysis for the cavern in stepped excavation without supporting were made; finally,the optimal time for supporting at the characteristic point in a typical section was obtained while the creep rate and displacement after each excavation step has satisfied the criterion of the optimal supporting time. Excavation was repeated when the optimal time for supporting was identified,and the long-term stability creep time and the maximum creep deformation of the characteristic point were determined in accordance with the criterion of long-term stability index. It is shown that the optimal supporting time of the characteristic point in the underground plant of Xiangjiaba hydro-power station is 5-8 d,the long-term stability time of the typical section is 126 d,and the corresponding largest creep deformation is 24.30 mm. While the cavern is supported,the cavern deformation is significantly reduced and the stress states of the surrounding rock masses are remarkably improved.
基金support by the National Nature Science Foundation of China(91433203,61564003,61474049,61774050,51502141)the Ministry of Science and Technology of China(2015AA034601)+2 种基金the Guangxi Natural Science Foundation(2015GXNSFGA139002)the Bagui Scholars Program of Guangxi,Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Materials,China Postdoctoral Science Foundation(2016M600588)the Project of Guangxi Graduate Education(YCSW2017148)
文摘Phenethylamine（PEA） was successfully introduced into hole-conductor-free, fully printable mesoscopic MAPbI3 perovskite solar cells（MPSCs） with a carbon electrode by mixing phenethylammonium iodide with MAPbI3 perovskite solution. PEA-MAPbI3 films show better pore filling into TiO2 scaffold that forms better contact, and induce longer exciton lifetime and higher quantum efficiency of photoinduced charge separation. As a result, the power conversion efficiency of PEA-MAPbI3 MPSCs is 37% higher than that of MAPbI3 MPSCs. And PEA-MAPbI3 MPSCs show excellent long-term stability that could keep 90% of origin power conversion efficiency for over 80 days in the air.
基金supported by Slovak Grant Agency(VEGA 1/0197/15)the Ministry of Education,Youth and Sport of the Czech Republic within the scope of project No.LO1207 of the programme NPU1
文摘Spherical Ag nanoparticles（AgNPs） were biologically synthesized using four different extracts prepared from Parachlorella kessleri algae cultivated for 1, 2, 3 and 4 weeks. The influence of algae life cycle on AgNPs formation and effect of different storage conditions on AgNPs long-term stability were investigated. The age of algae influenced the rate of AgNPs synthesis and amount of AgNPs in solution. The age of algae did not influence the AgNPs long-term stability. UV–vis and TEM observation revealed that long-term stability of AgNPs can be influenced by storage temperatures, and low temperature positively influences the AgNPs stability. AgNPs stored at dark and at temperature of ~5 °C showed the best long-term stability regardless of the culture age. Such AgNPs remained spherical, fine（5-20 nm） and stable（no agglomeration） even after 6 months.
基金support by the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(SKLGP2011K007)Chengdu University of Technology,the Key Research Program of the Chinese Academy of Sciences(KZZD-EW-05-02)+2 种基金by the National Natural Science Foundation of China(NSFC)(Nos.40972198,41172269)support is also from the Chinese Special Funds for Major State Basic Research Project under Grant No.2010CB732001Help provided by Master Chang Shen,Long Fu of Heidong CiEn Temple,and Mr.He Wantong during field investigations is thankfully acknowledged.
文摘Long-term stability of large span caverns is earnest but poorly understood in preservation of cultural relics.The life span of huge caverns is difficult to extrapolate from short period of monitoring or laboratory testing.A huge ancient quarry with 21 caverns whose original status is well kept over 1400 years was found in Tiantai County of South China.One of the caverns has an 81 m span which is far beyond the 50 m expectation on current knowledge.The tension at the core of long stability is the excavation speed versus deliberation.Here we show a unique technique of Digging Holes for Quarrying Vertical Flagstone(DQF)invented by ancestors to ensure the safety,which is much smarter compared to blasting and casting technique that commonly used after the Industrial Revolution.
