A wet-chemical method was presented for preparation of spherical, flowerlike, hexagonal, and triangular microsized silver crystals. Well-defined particles were prepared by mixing of iron(II) sulfate heptahydrate sol...A wet-chemical method was presented for preparation of spherical, flowerlike, hexagonal, and triangular microsized silver crystals. Well-defined particles were prepared by mixing of iron(II) sulfate heptahydrate solution with silver nitrate solution at the presence of different modifiers with high-speed stirring at 8-20℃. It is found that the diameters of resulting products are 0.6-6.0 um and the morphologies of the silver microcrystals are greatly affected by the introduced modifiers. It is concluded that the microsized silver crystals with different morphologies can be synthesized by introducing appropriate modifiers at appropriate experimental parameters. Scanning electron microscopy and X-ray diffraction were used to characterize the resulting products.展开更多
Recently, Hsieh and Horng [1] published the paper entitled as above. In section 3 results and discussion, the authors mentioned the first and the second order kinetic models without any quotations. In fact these two k...Recently, Hsieh and Horng [1] published the paper entitled as above. In section 3 results and discussion, the authors mentioned the first and the second order kinetic models without any quotations. In fact these two kinetic models have been published [2-5]. In order to distinguish a kinetics model based on the ad- sorption capacity of a solid from the one based on the concentration of a solution, Lagergren's first-order rate equation has been called pseudo-first-order [6-7]. The Lagergren's equation has been widely cited, but there are far more mistakes made in the quotation and in the reference section of papers, including the title, the author's name, journal title, year of publishing, volume, and page number [3]. In addition, the second order kinetic expression for the adsorption systems of divalent metal ions using sphagnum moss peat has been reported by Ho [8].展开更多
Microsized bismuth(Bi)with in-situ constructed three-dimensional(3D)porous network has been considered as a promising anode for high-performance potassium-ion batteries(PIBs).However,the mechanism of the in-situ porou...Microsized bismuth(Bi)with in-situ constructed three-dimensional(3D)porous network has been considered as a promising anode for high-performance potassium-ion batteries(PIBs).However,the mechanism of the in-situ porous evolution of microsized Bi during the charge/discharge process is still mysterious.Herein,various electrolytes are employed to disclose the origin of porous evolution of microsized Bi in PIBs.Experimentally and theoretically,the 3D porous network originates from the uniform interfacial charge distribution on the Bi surface in the linear ether-based electrolyte.In addition,the universality of the interfacial charge distribution mechanism was verified by microsized Sn and Sb.The in-situ constructed 3D porous network of Bi enables a superior potassium storage performance in a wide temperature range from-40 to 40℃.More importantly,the K_(0.9)Mn_(0.7)Ni_(0.3)O_(2)||Bi full cell delivers excellent cycling stability(a high capacity retention of 88.44%even after 2,000 cycles)and good temperature tolerance.This work gives a distinct clarification of the origin of the porous evolution of microsized Bi during cycling,which is critical for developing high-performance PIBs.展开更多
Silicon with high specific capacity is deemed an ideal anode material for lithium ion batteries,which,however suffers from low cycling life due to its dramatic volume changes.Water-soluble polymer binders recently gai...Silicon with high specific capacity is deemed an ideal anode material for lithium ion batteries,which,however suffers from low cycling life due to its dramatic volume changes.Water-soluble polymer binders recently gain increasing attention by providing an eco-friendly and low-cost way in improving the cycling stability of Si-based anodes.Herein,a novel bioinspired supramolecular mineral hydrogel binder consisting of polyacrylic acid (PAA) physically crosslinked with amorphous calcium carbonate (ACC) nanoparticles is designed for high-performance anodes made from low-cost microsized Si particles.Owing to its organic-inorganic hydrophilic nature,ACC-PAA hybrid binder exhibits the reported highest modulus (~22 GPa) for polymer binders in electrolyte,even higher than lithiated Si species (Li15Si4,~12 GPa).Together with its excellent adhesion and electrochemical stability,ACC-PAA binder can effectively suppress the pulverization of Si particles and maintain the mechanical integrity of electrodes during cycling.Therefore,even with a low binder content,the anode still shows an initial discharge capacity of 2,973 mAh·g^-1 and Coulombic efficiency of 81.5%,and retains 75% at a current density of 600 mA·g^-1 after 100 cycles.The present organic-inorganic hybrid mineral binder may open a new approach for designing more effective polymer binders for Si-based lithium-ion batteries.展开更多
To compare the cytotoxicity on HeLa cells induced by nanosized and microsized tellurium powders, HeLa cells were exposed to different concentrations of tellurium powders (0, 50, 100, 150 and 200 μg/mL) for 12 h. In...To compare the cytotoxicity on HeLa cells induced by nanosized and microsized tellurium powders, HeLa cells were exposed to different concentrations of tellurium powders (0, 50, 100, 150 and 200 μg/mL) for 12 h. In this study, detection of a series of biomarkers, including reactive oxygen species (ROS), glutathione (GSH), 8-hydroxy-2'- deoxyguanosine (8-OHdG), in addition to DNA and protein crosslink (DPC) and MTT assay, were conducted to evaluate the cytotoxicity. It is indicated that compared with the control group, there was no significant difference in the induced cytotoxicity at concentrations lower than 50 μg/mL for both nanosized and microsized tellurium powders. While there appears a significant difference in the induced cytotoxicity for nanosized tellurium powders when the concentration is higher than 100 μg/mL as well as for microsized tellurium powders when the concentration is higher than 200 μg/mL. Moreover, it is found that the cytotoxicity induced on HeLa cells exhibits a certain dose-effect relationship with the concentration of tellurium powders. A conclusion has been reached that the toxicity on HeLa cells can be induced by both nanosized and microsized tellurium powders, and the toxicity of the nanosized tellurium powders is significantly greater than the microsized one.展开更多
Microseism,acoustic emission and electromagnetic radiation(M-A-E)data are usually used for predicting rockburst hazards.However,it is a great challenge to realize the prediction of M-A-E data.In this study,with the ai...Microseism,acoustic emission and electromagnetic radiation(M-A-E)data are usually used for predicting rockburst hazards.However,it is a great challenge to realize the prediction of M-A-E data.In this study,with the aid of a deep learning algorithm,a new method for the prediction of M-A-E data is proposed.In this method,an M-A-E data prediction model is built based on a variety of neural networks after analyzing numerous M-A-E data,and then the M-A-E data can be predicted.The predicted results are highly correlated with the real data collected in the field.Through field verification,the deep learning-based prediction method of M-A-E data provides quantitative prediction data for rockburst monitoring.展开更多
There was an evident increase in the number of earthquakes in the Xinfengjiang Reservoir from June to July 2014 after the landing of Typhoon Hagibis.To understand the spatial and temporal evolution of this microseismi...There was an evident increase in the number of earthquakes in the Xinfengjiang Reservoir from June to July 2014 after the landing of Typhoon Hagibis.To understand the spatial and temporal evolution of this microseismicity,we built a high-precision earthquake catalog for 2014 and relocated 2275 events using recently developed methods for event picking and catalog construction.Seismicity occurred in the southeastern part of the reservoir,with the preferred fault plane orientation aligned along the Heyuan Fault.The total seismic energy peaked when the typhoon passed through the reservoir,and seismicity correlated with typhoon energy.In contrast,a limited seismic response was observed during the later Typhoon Rammasun.Combining data regarding the water level in the Xinfengjiang Reservoir and seismicity frequency changes in the Taiwan region during these two typhoon events,we suggest that typhoon activity may increase microseism energy by impacting fault stability around the Xinfengjiang Reservoir.Whether a fault can be activated also depends on how close the stress accumulation is to its failure point.展开更多
Shake table testing was performed to investigate the dynamic stability of a mid-dip bedding rock slope under frequent earthquakes. Then, numerical modelling was established to further study the slope dynamic stability...Shake table testing was performed to investigate the dynamic stability of a mid-dip bedding rock slope under frequent earthquakes. Then, numerical modelling was established to further study the slope dynamic stability under purely microseisms and the influence of five factors, including seismic amplitude, slope height, slope angle, strata inclination and strata thickness, were considered. The experimental results show that the natural frequency of the slope decreases and damping ratio increases as the earthquake loading times increase. The dynamic strength reduction method is adopted for the stability evaluation of the bedding rock slope in numerical simulation, and the slope stability decreases with the increase of seismic amplitude, increase of slope height, reduction of strata thickness and increase of slope angle. The failure mode of a mid-dip bedding rock slope in the shaking table test is integral slipping along the bedding surface with dipping tensile cracks at the slope rear edge going through the bedding surfaces. In the numerical simulation, the long-term stability of a mid-dip bedding slope is worst under frequent microseisms and the slope is at risk of integral sliding instability, whereas the slope rock mass is more broken than shown in the shaking table test. The research results are of practical significance to better understand the formation mechanism of reservoir landslides and prevent future landslide disasters.展开更多
In this paper we give a review of several previously published papers on anomalous tremors observed before the 2008 Ms8.0 Weuchuan earthquake. Based on the observed time and frequency shifts between coastal and inland...In this paper we give a review of several previously published papers on anomalous tremors observed before the 2008 Ms8.0 Weuchuan earthquake. Based on the observed time and frequency shifts between coastal and inland stations, we discussed some methods to distinguish different kinds of microseisms, and speculated that a pre-earthquake typhoon might have caused a "mainland-originated microseism" which in turn trig- gered the earthquake.展开更多
We present second-order expressions for the free-surface elevation, velocity potential and pressure resulting from the interaction of surface waves in water of arbitrary depth. When the surface waves have nearly equal...We present second-order expressions for the free-surface elevation, velocity potential and pressure resulting from the interaction of surface waves in water of arbitrary depth. When the surface waves have nearly equal frequencies and nearly opposite directions, a second-order pressure can be felt all the way to the sea bottom. There are at least two areas of applications: reflective structures and microseisms. Microseisms generated by water waves in the ocean are small vibrations of the ground resulting from pressure oscillations associated with the coupling of ocean surface gravity waves and the sea floor. They are recorded on land-based seismic stations throughout the world and they are divided into primary and secondary types, as a function of spectral content. Secondary microseisms are generated by the interaction of surface waves with nearly equal frequencies and nearly opposite directions. The efficiency of microseism generation thus depends in part on ocean wave frequency and direction. Based on the second-order expressions for the dynamic pressure, a simple theoretical analysis that quantifies the degree of nearness in amplitude, frequency, and incidence angle, which must be reached to observe the phenomenon, is presented.展开更多
The temporal and spatial distributions of Antarctic sea ice play important roles in both the generation mechanisms and the signal characteristics of microseisms. This link paves the way for seismological investigation...The temporal and spatial distributions of Antarctic sea ice play important roles in both the generation mechanisms and the signal characteristics of microseisms. This link paves the way for seismological investigations of Antarctic sea ice. Here we present an overview of the current state of seismological research about microseisms on Antarctic sea ice. We first briefly review satellite remote-sensing observations of Antarctic sea ice over the past 50 years. We then systematically expound upon the generation mechanisms and source distribution of microseisms in relation to seismic noise investigations of sea ice, and the characteristics of Antarctic microseisms and relationship with sea ice variations are further analyzed. We also analyze the continuous data recorded at seismic station BEAR in West Antarctica from 2011 to 2018 and compare the microseism observations with the corresponding satellite remotesensing observations of Antarctic sea ice. Our results show that:(1) the microseisms from the coastal regions of West Antarctica exhibit clear seasonal variations,SFM with maximum intensities every April-May and minimum intensities around every October-November;while DFM intensities peak every February-March,and reach the minimum around every October. Comparatively,the strong seasonal periodicity of Antarctic sea ice in better agreement with the observed DFM;and(2) microseism decay is not synchronous with sea ice expansion since the microseism intensity is also linked to the source location,source intensity(e. g.,ocean storms,ocean wave field),and other factors. Finally, we discuss the effect of Southern Annular Mode on Antarctic sea ice and microseisms,as well as the current limitations and potential of employing seismological investigations to elucidate Antarctic sea ice variations and climate change.展开更多
文摘A wet-chemical method was presented for preparation of spherical, flowerlike, hexagonal, and triangular microsized silver crystals. Well-defined particles were prepared by mixing of iron(II) sulfate heptahydrate solution with silver nitrate solution at the presence of different modifiers with high-speed stirring at 8-20℃. It is found that the diameters of resulting products are 0.6-6.0 um and the morphologies of the silver microcrystals are greatly affected by the introduced modifiers. It is concluded that the microsized silver crystals with different morphologies can be synthesized by introducing appropriate modifiers at appropriate experimental parameters. Scanning electron microscopy and X-ray diffraction were used to characterize the resulting products.
文摘Recently, Hsieh and Horng [1] published the paper entitled as above. In section 3 results and discussion, the authors mentioned the first and the second order kinetic models without any quotations. In fact these two kinetic models have been published [2-5]. In order to distinguish a kinetics model based on the ad- sorption capacity of a solid from the one based on the concentration of a solution, Lagergren's first-order rate equation has been called pseudo-first-order [6-7]. The Lagergren's equation has been widely cited, but there are far more mistakes made in the quotation and in the reference section of papers, including the title, the author's name, journal title, year of publishing, volume, and page number [3]. In addition, the second order kinetic expression for the adsorption systems of divalent metal ions using sphagnum moss peat has been reported by Ho [8].
基金supported by the National Natural Science Foundation of China(No.22005082,52202286)Natural Science Foundation of Hebei Province(No.B2020202065)+2 种基金the Special Project of Local Science and Technology Development Guided by the Central Government of China(226Z4402G)Science Research Project of Hebei Education Department(No.QN2020209,CXY2024036)Basic Research Project of Wenzhou City(G20220016)。
文摘Microsized bismuth(Bi)with in-situ constructed three-dimensional(3D)porous network has been considered as a promising anode for high-performance potassium-ion batteries(PIBs).However,the mechanism of the in-situ porous evolution of microsized Bi during the charge/discharge process is still mysterious.Herein,various electrolytes are employed to disclose the origin of porous evolution of microsized Bi in PIBs.Experimentally and theoretically,the 3D porous network originates from the uniform interfacial charge distribution on the Bi surface in the linear ether-based electrolyte.In addition,the universality of the interfacial charge distribution mechanism was verified by microsized Sn and Sb.The in-situ constructed 3D porous network of Bi enables a superior potassium storage performance in a wide temperature range from-40 to 40℃.More importantly,the K_(0.9)Mn_(0.7)Ni_(0.3)O_(2)||Bi full cell delivers excellent cycling stability(a high capacity retention of 88.44%even after 2,000 cycles)and good temperature tolerance.This work gives a distinct clarification of the origin of the porous evolution of microsized Bi during cycling,which is critical for developing high-performance PIBs.
基金the National Natural Science Foundation of China (NSFC)(Nos.51733003 and 51873035).
文摘Silicon with high specific capacity is deemed an ideal anode material for lithium ion batteries,which,however suffers from low cycling life due to its dramatic volume changes.Water-soluble polymer binders recently gain increasing attention by providing an eco-friendly and low-cost way in improving the cycling stability of Si-based anodes.Herein,a novel bioinspired supramolecular mineral hydrogel binder consisting of polyacrylic acid (PAA) physically crosslinked with amorphous calcium carbonate (ACC) nanoparticles is designed for high-performance anodes made from low-cost microsized Si particles.Owing to its organic-inorganic hydrophilic nature,ACC-PAA hybrid binder exhibits the reported highest modulus (~22 GPa) for polymer binders in electrolyte,even higher than lithiated Si species (Li15Si4,~12 GPa).Together with its excellent adhesion and electrochemical stability,ACC-PAA binder can effectively suppress the pulverization of Si particles and maintain the mechanical integrity of electrodes during cycling.Therefore,even with a low binder content,the anode still shows an initial discharge capacity of 2,973 mAh·g^-1 and Coulombic efficiency of 81.5%,and retains 75% at a current density of 600 mA·g^-1 after 100 cycles.The present organic-inorganic hybrid mineral binder may open a new approach for designing more effective polymer binders for Si-based lithium-ion batteries.
文摘To compare the cytotoxicity on HeLa cells induced by nanosized and microsized tellurium powders, HeLa cells were exposed to different concentrations of tellurium powders (0, 50, 100, 150 and 200 μg/mL) for 12 h. In this study, detection of a series of biomarkers, including reactive oxygen species (ROS), glutathione (GSH), 8-hydroxy-2'- deoxyguanosine (8-OHdG), in addition to DNA and protein crosslink (DPC) and MTT assay, were conducted to evaluate the cytotoxicity. It is indicated that compared with the control group, there was no significant difference in the induced cytotoxicity at concentrations lower than 50 μg/mL for both nanosized and microsized tellurium powders. While there appears a significant difference in the induced cytotoxicity for nanosized tellurium powders when the concentration is higher than 100 μg/mL as well as for microsized tellurium powders when the concentration is higher than 200 μg/mL. Moreover, it is found that the cytotoxicity induced on HeLa cells exhibits a certain dose-effect relationship with the concentration of tellurium powders. A conclusion has been reached that the toxicity on HeLa cells can be induced by both nanosized and microsized tellurium powders, and the toxicity of the nanosized tellurium powders is significantly greater than the microsized one.
基金supported by the National Natural Science Foundation of China(Grant No.51934007)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20220691).
文摘Microseism,acoustic emission and electromagnetic radiation(M-A-E)data are usually used for predicting rockburst hazards.However,it is a great challenge to realize the prediction of M-A-E data.In this study,with the aid of a deep learning algorithm,a new method for the prediction of M-A-E data is proposed.In this method,an M-A-E data prediction model is built based on a variety of neural networks after analyzing numerous M-A-E data,and then the M-A-E data can be predicted.The predicted results are highly correlated with the real data collected in the field.Through field verification,the deep learning-based prediction method of M-A-E data provides quantitative prediction data for rockburst monitoring.
基金Strategic Priority Research Program(B)of the Chinese Academy of Sciences(No.XDB42020304)National Natural Science Foundation of China(No.42074059).
文摘There was an evident increase in the number of earthquakes in the Xinfengjiang Reservoir from June to July 2014 after the landing of Typhoon Hagibis.To understand the spatial and temporal evolution of this microseismicity,we built a high-precision earthquake catalog for 2014 and relocated 2275 events using recently developed methods for event picking and catalog construction.Seismicity occurred in the southeastern part of the reservoir,with the preferred fault plane orientation aligned along the Heyuan Fault.The total seismic energy peaked when the typhoon passed through the reservoir,and seismicity correlated with typhoon energy.In contrast,a limited seismic response was observed during the later Typhoon Rammasun.Combining data regarding the water level in the Xinfengjiang Reservoir and seismicity frequency changes in the Taiwan region during these two typhoon events,we suggest that typhoon activity may increase microseism energy by impacting fault stability around the Xinfengjiang Reservoir.Whether a fault can be activated also depends on how close the stress accumulation is to its failure point.
基金National Natural Science Foundation of China under Grant No. 41372356the College Cultivation Project of the National Natural Science Foundation of China under Grant No. 2018PY30+1 种基金the Basic Research and Frontier Exploration Project of Chongqing,China under Grant No. cstc2018jcyj A1597the Graduate Scientific Research and Innovation Foundation of Chongqing,China under Grant No. CYS18026。
文摘Shake table testing was performed to investigate the dynamic stability of a mid-dip bedding rock slope under frequent earthquakes. Then, numerical modelling was established to further study the slope dynamic stability under purely microseisms and the influence of five factors, including seismic amplitude, slope height, slope angle, strata inclination and strata thickness, were considered. The experimental results show that the natural frequency of the slope decreases and damping ratio increases as the earthquake loading times increase. The dynamic strength reduction method is adopted for the stability evaluation of the bedding rock slope in numerical simulation, and the slope stability decreases with the increase of seismic amplitude, increase of slope height, reduction of strata thickness and increase of slope angle. The failure mode of a mid-dip bedding rock slope in the shaking table test is integral slipping along the bedding surface with dipping tensile cracks at the slope rear edge going through the bedding surfaces. In the numerical simulation, the long-term stability of a mid-dip bedding slope is worst under frequent microseisms and the slope is at risk of integral sliding instability, whereas the slope rock mass is more broken than shown in the shaking table test. The research results are of practical significance to better understand the formation mechanism of reservoir landslides and prevent future landslide disasters.
基金supported by the National Natural Science Foundation of China(90814009)Quality Control’s Special Funds for Scientific Researchon Public Causes(10-215)National Key Technology Research and Development Program(2008BAC35B05)
文摘In this paper we give a review of several previously published papers on anomalous tremors observed before the 2008 Ms8.0 Weuchuan earthquake. Based on the observed time and frequency shifts between coastal and inland stations, we discussed some methods to distinguish different kinds of microseisms, and speculated that a pre-earthquake typhoon might have caused a "mainland-originated microseism" which in turn trig- gered the earthquake.
基金partly supported by the Science Foundation Ireland(SFI)under the research project "High-end computational modeling for wave energy systems"(SFI/10/IN.1/12996)in collaboration with Marine Renewable Energy Ireland(MaREI)the SFI Centre for Marine Renewable Energy Research(SFI/12/RC/2302)
文摘We present second-order expressions for the free-surface elevation, velocity potential and pressure resulting from the interaction of surface waves in water of arbitrary depth. When the surface waves have nearly equal frequencies and nearly opposite directions, a second-order pressure can be felt all the way to the sea bottom. There are at least two areas of applications: reflective structures and microseisms. Microseisms generated by water waves in the ocean are small vibrations of the ground resulting from pressure oscillations associated with the coupling of ocean surface gravity waves and the sea floor. They are recorded on land-based seismic stations throughout the world and they are divided into primary and secondary types, as a function of spectral content. Secondary microseisms are generated by the interaction of surface waves with nearly equal frequencies and nearly opposite directions. The efficiency of microseism generation thus depends in part on ocean wave frequency and direction. Based on the second-order expressions for the dynamic pressure, a simple theoretical analysis that quantifies the degree of nearness in amplitude, frequency, and incidence angle, which must be reached to observe the phenomenon, is presented.
基金sponsored by the National Key R&D Program of China(2018YFC1503204)the National Natural Science Foundation of China(41874046)。
文摘The temporal and spatial distributions of Antarctic sea ice play important roles in both the generation mechanisms and the signal characteristics of microseisms. This link paves the way for seismological investigations of Antarctic sea ice. Here we present an overview of the current state of seismological research about microseisms on Antarctic sea ice. We first briefly review satellite remote-sensing observations of Antarctic sea ice over the past 50 years. We then systematically expound upon the generation mechanisms and source distribution of microseisms in relation to seismic noise investigations of sea ice, and the characteristics of Antarctic microseisms and relationship with sea ice variations are further analyzed. We also analyze the continuous data recorded at seismic station BEAR in West Antarctica from 2011 to 2018 and compare the microseism observations with the corresponding satellite remotesensing observations of Antarctic sea ice. Our results show that:(1) the microseisms from the coastal regions of West Antarctica exhibit clear seasonal variations,SFM with maximum intensities every April-May and minimum intensities around every October-November;while DFM intensities peak every February-March,and reach the minimum around every October. Comparatively,the strong seasonal periodicity of Antarctic sea ice in better agreement with the observed DFM;and(2) microseism decay is not synchronous with sea ice expansion since the microseism intensity is also linked to the source location,source intensity(e. g.,ocean storms,ocean wave field),and other factors. Finally, we discuss the effect of Southern Annular Mode on Antarctic sea ice and microseisms,as well as the current limitations and potential of employing seismological investigations to elucidate Antarctic sea ice variations and climate change.