We present a short and simple proof of the recent result of Yang and Wang [12]. Stimulated by their idea, two geometric parameters Uax（ε） and βx （ε）, both related to Gao＇s modulus of U-convexity of a Banach sp...We present a short and simple proof of the recent result of Yang and Wang [12]. Stimulated by their idea, two geometric parameters Uax（ε） and βx （ε）, both related to Gao＇s modulus of U-convexity of a Banach space X, are introduced. Their properties and the relationships with normal structure are studied. Some existing results involving normal structure and fixed points for non-expansive mappings in Banach spaces are improved.展开更多
Detecting subsurface fault structure is important for evaluating potential earthquake risks associated with active faults.In this study,we propose a new method to detect faults using reflected surface waves observed i...Detecting subsurface fault structure is important for evaluating potential earthquake risks associated with active faults.In this study,we propose a new method to detect faults using reflected surface waves observed in ambient noise cross correlation functions.Ambient noise tomography using direct surface waves obtained from ambient noise interferometry has been widely used to characterize active fault zones.In cases where a strong velocity contrast exists across the fault interface,fault-reflected surface waves are expected.We test this idea using a linear array deployed in the Suqian segment of Tanlu fault zone in Eastern China.The fault-reflected surface waves can be clearly seen in the cross-correlation functions of the ambient noise data,and the spatial position of the fault on the surface is close to the stations where the reflected signals first appear.Potentially reflected surface waves could also be used to infer the dip angle,fault zone thickness and the degree of velocity contrast across the fault by comparing synthetic and observed waveforms.展开更多
The critical factor of spatial constraint,provided by the external confinement(e.g.,matrix),is often overlooked during photodynamic inactivation,despite playing a crucial role in determining the molecular photophysica...The critical factor of spatial constraint,provided by the external confinement(e.g.,matrix),is often overlooked during photodynamic inactivation,despite playing a crucial role in determining the molecular photophysical process and subsequent antipathogen performance.Here,as a proof-of-concept model,we employed two types of polymers with varying interaction energies with dopants to investigate the intrinsic relationship between spatial constraint and the essential excited-state behaviors of doped photosensitizer(4-(2-(5-(4-(diphenylamino)phenyl)thiophen-2-yl)ethyl)-1-methylquinolin-1-ium iodine,TPP).Through experimental investigation and theoretical calculations,we found that TPP tends to remain in the excited state for a shorter dwell time under weaker spatial constraints due to less restricted molecular motion in polyurethane(PU) nanofibers.Consequently,the singlet oxygen(^(1)O_(2)) generated from doped-TPP shows a 9.23-fold enhancement in PU than in the polyvinylchloride(PVC) matrix.Under light irradiation,the PU@TPP nanofiber can efficiently eliminate the coronavirus MHV-A59(≥99.9997%) at a 220,000-fold higher concentration than the infected space.Its antibacterial efficacy has also been demonstrated,with a killing rate of ≥99%.展开更多
Quantitatively analysing the impacts on regional water sustainability under the energy transition is vital to regional water management and specific technology selection,which is also relevant to dealing with climate ...Quantitatively analysing the impacts on regional water sustainability under the energy transition is vital to regional water management and specific technology selection,which is also relevant to dealing with climate change.This study proposed a new multi-indicator evaluation framework for regional water sustainability under local energy transition to quantitatively evaluate the water withdrawal and water environment during the energy transition from a lifecycle perspective.An integrated regional energy-water evaluation model was also developed based on the Low Emissions Analysis Platform with a combination of lifecycle assessment and water footprint analysis.Shaanxi province in China was then taken as a case study,and the impacts of its energy transition on regional water environmental sustainability,including quantity and quality,were investigated under five scenarios.Results showed that the large-scale application of carbon capture,utilisation and storage technology and bio-energy equipped with carbon capture and storage technology could have additional advantages regarding CO_(2) emissions.However,such technologies exhibit a minimal effect on improving water environmental quality and reducing water demand for the first time due to the leakage of absorbents,CO_(2) and other risky substances during capture,transportation and storage from a lifecycle perspective.This finding drives the innovation of related breakthrough technologies with the promotion of water and end-treatment technologies in the future.展开更多
Low-frequency signals have been widely found in the conventional oil/gas field and volcanic region as well as during hydraulic fracturing of unconventional oil/gas reservoirs.Their generation mechanism has been ascrib...Low-frequency signals have been widely found in the conventional oil/gas field and volcanic region as well as during hydraulic fracturing of unconventional oil/gas reservoirs.Their generation mechanism has been ascribed to the flow of gas/fluid in the fractures,which can induce the Krauklis wave around fractures and can further excite low-frequency seismic body wave signals at diffraction points.Thus,it is theoretically feasible to determine the gas/fluid enrichment areas and migration pathways by locating the low-frequency signals.Here we have utilized a surface dense seismic array deployed above the Sijiazhuang coal mine in Shanxi province to detect and locate such low-frequency signals that are dominant in the frequency range of 1.5–4.0 Hz.Waveform migrationbased location method is employed to locate these signals that have low signal to noise ratios.We further compare the distribution of low-frequency signals and coalbed methane concentrations that are estimated based on ambient noise tomography result with the same seismic array.The spatial consistency between low-frequency signals and coalbed methane enrichment areas suggests that detecting and locating low-frequency signals with a surface seismic array is an efficient way to identify gas enrichment areas and potential gas migration pathways.展开更多
文摘We present a short and simple proof of the recent result of Yang and Wang [12]. Stimulated by their idea, two geometric parameters Uax（ε） and βx （ε）, both related to Gao＇s modulus of U-convexity of a Banach space X, are introduced. Their properties and the relationships with normal structure are studied. Some existing results involving normal structure and fixed points for non-expansive mappings in Banach spaces are improved.
基金supported by the National Key R&D Program of China(2018YFC1504102)National Natural Science Foundation of China(41961134001).
文摘Detecting subsurface fault structure is important for evaluating potential earthquake risks associated with active faults.In this study,we propose a new method to detect faults using reflected surface waves observed in ambient noise cross correlation functions.Ambient noise tomography using direct surface waves obtained from ambient noise interferometry has been widely used to characterize active fault zones.In cases where a strong velocity contrast exists across the fault interface,fault-reflected surface waves are expected.We test this idea using a linear array deployed in the Suqian segment of Tanlu fault zone in Eastern China.The fault-reflected surface waves can be clearly seen in the cross-correlation functions of the ambient noise data,and the spatial position of the fault on the surface is close to the stations where the reflected signals first appear.Potentially reflected surface waves could also be used to infer the dip angle,fault zone thickness and the degree of velocity contrast across the fault by comparing synthetic and observed waveforms.
基金supported by the Shenzhen Science and Technology Program (JSGG20200225151916021)the National Natural Science Foundation of China (U21A2097)+3 种基金Department of Science and Technology of Guangdong Province (2019ZT08Y191,2019QN01Y640)Guangdong Provincial Key Laboratory of Advanced Biomaterials(2022B1212010003)Shenzhen Key Laboratory of Smart Healthcare Engineering (ZDSYS20200811144003009)Shenzhen Science and Technology Program (KQTD20190929172743294)。
文摘The critical factor of spatial constraint,provided by the external confinement(e.g.,matrix),is often overlooked during photodynamic inactivation,despite playing a crucial role in determining the molecular photophysical process and subsequent antipathogen performance.Here,as a proof-of-concept model,we employed two types of polymers with varying interaction energies with dopants to investigate the intrinsic relationship between spatial constraint and the essential excited-state behaviors of doped photosensitizer(4-(2-(5-(4-(diphenylamino)phenyl)thiophen-2-yl)ethyl)-1-methylquinolin-1-ium iodine,TPP).Through experimental investigation and theoretical calculations,we found that TPP tends to remain in the excited state for a shorter dwell time under weaker spatial constraints due to less restricted molecular motion in polyurethane(PU) nanofibers.Consequently,the singlet oxygen(^(1)O_(2)) generated from doped-TPP shows a 9.23-fold enhancement in PU than in the polyvinylchloride(PVC) matrix.Under light irradiation,the PU@TPP nanofiber can efficiently eliminate the coronavirus MHV-A59(≥99.9997%) at a 220,000-fold higher concentration than the infected space.Its antibacterial efficacy has also been demonstrated,with a killing rate of ≥99%.
基金supported by the Department of Science and Technology of Zhejiang province in China (Pioneer and Bellwethers R&D Projects,2022C03119)the Environmental Defense Fund (EDF-B-2019,and 20220023).
文摘Quantitatively analysing the impacts on regional water sustainability under the energy transition is vital to regional water management and specific technology selection,which is also relevant to dealing with climate change.This study proposed a new multi-indicator evaluation framework for regional water sustainability under local energy transition to quantitatively evaluate the water withdrawal and water environment during the energy transition from a lifecycle perspective.An integrated regional energy-water evaluation model was also developed based on the Low Emissions Analysis Platform with a combination of lifecycle assessment and water footprint analysis.Shaanxi province in China was then taken as a case study,and the impacts of its energy transition on regional water environmental sustainability,including quantity and quality,were investigated under five scenarios.Results showed that the large-scale application of carbon capture,utilisation and storage technology and bio-energy equipped with carbon capture and storage technology could have additional advantages regarding CO_(2) emissions.However,such technologies exhibit a minimal effect on improving water environmental quality and reducing water demand for the first time due to the leakage of absorbents,CO_(2) and other risky substances during capture,transportation and storage from a lifecycle perspective.This finding drives the innovation of related breakthrough technologies with the promotion of water and end-treatment technologies in the future.
基金supported by National Natural Science Foundation of China under grant 41961134991。
文摘Low-frequency signals have been widely found in the conventional oil/gas field and volcanic region as well as during hydraulic fracturing of unconventional oil/gas reservoirs.Their generation mechanism has been ascribed to the flow of gas/fluid in the fractures,which can induce the Krauklis wave around fractures and can further excite low-frequency seismic body wave signals at diffraction points.Thus,it is theoretically feasible to determine the gas/fluid enrichment areas and migration pathways by locating the low-frequency signals.Here we have utilized a surface dense seismic array deployed above the Sijiazhuang coal mine in Shanxi province to detect and locate such low-frequency signals that are dominant in the frequency range of 1.5–4.0 Hz.Waveform migrationbased location method is employed to locate these signals that have low signal to noise ratios.We further compare the distribution of low-frequency signals and coalbed methane concentrations that are estimated based on ambient noise tomography result with the same seismic array.The spatial consistency between low-frequency signals and coalbed methane enrichment areas suggests that detecting and locating low-frequency signals with a surface seismic array is an efficient way to identify gas enrichment areas and potential gas migration pathways.
文摘Nature于2019年末选出了其创刊150年历史上出版.过的最具有历史影响力的10篇论文,其中包括剑桥大学的阿根廷生物学家CesarMilstein(色萨·米尔斯坦)和德国生物学家Georges J.F.Kohler(乔治斯·科勒)在1975年发表的文章,他们提出的利用杂交瘤细胞生产单克隆抗体(monoclonal antibody)的方法,为此后半个世纪的免疫学以及癌症和自身免疫性疾病治疗的医学研究提供了重要的工具和思路.此文一经发表,就引发了领域内研究者们的热切关注.当时德国科隆大学(Universitat zu KoIn)的免疫学家Rajewsky在为Nature撰写的新闻稿中这么评论道:“我当时立刻意识到我们的研究领域迎来了一个转折点.”
