We present the results of the multi-epoch broadband spectral study of 1ES 2344+514 and study the evolution of physical parameters.We used nearly simultaneous data obtained from 2017 June 6 to 2022 August 6(MJD 57910–...We present the results of the multi-epoch broadband spectral study of 1ES 2344+514 and study the evolution of physical parameters.We used nearly simultaneous data obtained from 2017 June 6 to 2022 August 6(MJD 57910–59797)in optical,UV,X-ray andγ-ray wavebands from various instruments including Swift-UVOT,Swift-XRT,Nuclear Spectroscopic Telescope Array(NuSTAR),AstroSat(SXT and LAXPC),Fermi-LAT,and TeV flux from MAGIC.During 2017 July,1ES 2344+514 appeared to be in the highest flaring state compared to other periods.We used the 0.5–7.0 keV and 3.0–20.0 keV data,respectively,from SXT and LAXPC of AstroSat and also 0.3–8.0 keV and 3.0–79.0 keV data,respectively,from Swift-XRT and NuSTAR.A joint fit between SXT and LAXPC,and between Swift-XRT and NuSTAR has been done for constraining the synchrotron peak.A clear shift in the synchrotron peak has been observed,which included 1ES 2344+514 in the HSP BL Lac family.A“harder-when-brighter”trend is observed in X-rays,and the opposite trend,i.e.,“softer-when-brighter,”is seen in theγ-rays.The multi-epoch broadband spectral energy distributions(SEDs)of this source were built and studied to get an idea of the radiation processes.The SEDs were fitted using a steady-state leptonic one-zone synchrotron+SSC model,and the fitted parameters of the emission region are consistent with those of other TeV BL Lacs.In this study,we found a weak correlation tendency between bolometric luminosity and magnetic field(B),as well as between bolometric luminosity and the break Lorentz factor(γ_(break)).展开更多
为克服柔性传感器在灵敏度较低、生产流程复杂以及透气性不足等方面的挑战,本研究通过针刺-热熔技术制备了一种三维聚乙烯-聚丙烯(Ethylene-propylene side by side,ES)/聚酯(PET)纤维非织造材料。随后,利用碳纳米管(CNT)对该材料进行...为克服柔性传感器在灵敏度较低、生产流程复杂以及透气性不足等方面的挑战,本研究通过针刺-热熔技术制备了一种三维聚乙烯-聚丙烯(Ethylene-propylene side by side,ES)/聚酯(PET)纤维非织造材料。随后,利用碳纳米管(CNT)对该材料进行浸渍处理,成功开发了一种性能优异的CNT包覆三维ES/PET非织造基压力传感器,并对比分析了不同CNT浸渍时间和浸渍次数对传感器性能的影响。研究结果显示,该CNT包覆三维ES/PET非织造基柔性压力传感器具有高达0.375 kPa^(-1)的灵敏度和0~214.526 kPa的检测范围。经过2100次压缩循环,传感器展现了优异的稳定性和可重复性,响应时间为48 ms,恢复时间为122 ms。在实际应用中,该传感器能够精确识别如呼吸、吞咽、手指弯曲等人体细微生理活动,在运动、医疗、虚拟现实等多个领域具有潜在的广泛应用。展开更多
To investigate the differences in combustion and energy release characteristics of metastable intermolecular composite materials composed of aluminum alloys and polyvinylidene fluoride(PVDF)with different compositions...To investigate the differences in combustion and energy release characteristics of metastable intermolecular composite materials composed of aluminum alloys and polyvinylidene fluoride(PVDF)with different compositions,two types of alloys were selected:Al-Mg and Al-Si.Pure aluminum powder of the same size was also chosen for comparison.The PVDF-coated metal particle composites and the mixtures of PVDF with metal particles were prepared using electrospray(ES)and physical blending methods(PM),respectively.A systematic study was conducted on the morphology,compositional structure,combustion performance,energy release characteristics,and thermal reactivity of the fabricated composites and their combustion products through scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDS),X-ray diffraction(XRD),combustion performance experiments,closed vessel pressure tests,and simultaneous thermogravimetric-differential scanning calorimetry(TG-DSC).The experimental results indicated that the PVDF-coated metal particles prepared by the electrospray method exhibited a distinct core-shell structure,with the metal particles in close contact with the PVDF matrix.Compared to the PM blended materials,the ES composites demonstrated superior combustion performance and energy release characteristics during combustion.Analysis of different metal fuel systems under identical preparation conditions revealed that Al-Mg and Al-Si fuels modulate the combustion and energy release properties of aluminum alloy-PVDF MICs through two distinct pathways.展开更多
Ecosystems play a pivotal role in advancing Sustainable Development Goals(SDGs)by providing indispensable and resilient ecosystem services(ESs).However,the limited analysis of spatiotemporal heterogeneity often re str...Ecosystems play a pivotal role in advancing Sustainable Development Goals(SDGs)by providing indispensable and resilient ecosystem services(ESs).However,the limited analysis of spatiotemporal heterogeneity often re stricts the recognition of ESs’roles in attaining SDGs and landscape planning.We selected 183 counties in the Sichuan Province as the study area and mapped 10 SDGs and 7 ESs from 2000 to 2020.We used correlation analysis,principal component analysis,Geographically and Temporally Weighted Regression model,and self organizing maps to reveal the spatiotemporal heterogeneity of the impacts of the bundle of ESs on the SDGs and to develop spatial planning and management strategies.The results showed that(1)SDGs were improved in all counties,with SDG 1(No Poverty)and SDG 3(Good Health and Well-being)exhibiting poor performance.West ern Sichuan demonstrated stronger performance in environment-related SDGs in the Sichuan Province,while the Sichuan Basin showed better progress in socio-economic-related SDGs;(2)habitat quality,carbon sequestration,air pollution removal,and soil retention significantly influenced the development of 9 SDGs;(3)supporting,regulating,and provisioning service bundles have persistent and stable spatiotemporal heterogeneity effects on SDG1,SDG8,SDG11,SDG13,and SDG15.These findings substantiate the need for integrated management of multiple ESs and facilitate the regional achievement of SDGs in geographically intricate areas.展开更多
Electrolyte additives are pivotal for stable cycling of rechargeable sodium-ion batteries(SIBs),which dictate the creation of the protective interface film on electrodes.Cyclic sulfur-containing additives,such as1,3,2...Electrolyte additives are pivotal for stable cycling of rechargeable sodium-ion batteries(SIBs),which dictate the creation of the protective interface film on electrodes.Cyclic sulfur-containing additives,such as1,3,2-dioxathiolane-2,2-dioxide(DTD),with the structure of sulfur surrounded by four oxygen atoms,have been proposed but less knowledge is available on the relationship between their molecular structures and interfacial stability.This work compares two similar molecule structure of cyclic sulfurcontaining additives,DTD and ethylene sulfite(ES),to investigate their effects on the electrochemical performance of NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM)||hard carbon(HC)pouch cells.Therein,ES with the structure of sulfur surrounded by three oxygen atoms,as electrolyte additive,is investigated in the SIBs for the first time.It is shown that adding 3.0%ES or 2.0%DTD(the optimal proportion)in the Control electrolyte(1 M NaPF_(6)in EC:EMC=3:7 with 5.0%FEC in weight)can improve cyclic stability and rate performance,respectively.Even under the high-temperature conditions,both ES and DTD exhibit good performance,but DTD is superior.Combinations of electrochemical methods,multi-spectroscopy,and theoretical calculations have been employed to evaluate and compare the effects of ES and DTD on sodium-ion battery.They reveal that ES and DTD can generate different content and composition by redox reaction on cathode and anode surface.The more and effective high-valence sulfur-containing components for DTD are the main reason to explain the better effect on DTD.This work shares new insights into the relationship between cyclic sulfur-containing additive molecule structure and electrolyte-electrode interface films effect,which fills the blanks of previous research.展开更多
Background: Improving Water, Sanitation and Hygiene in health care settings is a critical prerequisite for achieving national health goals and Sustainable Development Goals (SDGs). The World Health Organization (WHO) ...Background: Improving Water, Sanitation and Hygiene in health care settings is a critical prerequisite for achieving national health goals and Sustainable Development Goals (SDGs). The World Health Organization (WHO) has set a target for each United Nations member state to reach by 2030. Each member state is required to reach by 2022, 2025 and 2030 at least 60%, 80% and 100%, respectively of basic level of service of the five elements which are water, sanitation, hygiene, waste management and environmental cleaning. Methods: This study aimed to evaluate and document the current state of basic water, sanitation, and hygiene services in all lower-level health care facilities in the Dar es Salaam region of Tanzania as of July 2022. A cross-sectional study was conducted in 99 public dispensaries in the Dar es Salaam region’s five councils: Ubungo, Kigamboni, Kinondoni and Temeke Municipalities, and Ilala City. The interviewee form and observational checklists were both digitalized using the Kobo tool software. The respondents were health care facility in-charges or nurse in-charges. Data were downloaded, validated, and imported to Stata version 15 for analysis. Results: The basic WASH level per JMP is far below the target in 2022. Each member state by 2022 is required to reach at least 60% of the basic level of service of each element. We found a low coverage of basic WASH in the 99 dispensaries included in this study. The basic WASH coverage was met in only 10 (10.1%) of the dispensaries, while the remaining 89 (89.9%) dispensaries fall on limited WASH services. Conclusion: This study revealed lower coverage of basic WASH services in dispensaries. An urgent need is required to improve the status of WASH in all the dispensaries and facilitate the provision of quality health care services, patient safety and reduce health care associated infections.展开更多
The Chezhen depression,located in the south of Bohai Bay Basin,is an oil-producing basin in China. The third and fourth members of the Shahejie Formation(E(s3) and E(s4)) are the main source rock series in the Chezhen...The Chezhen depression,located in the south of Bohai Bay Basin,is an oil-producing basin in China. The third and fourth members of the Shahejie Formation(E(s3) and E(s4)) are the main source rock series in the Chezhen depression. Widespread overpressures occurred in the E(s3) and E(s4) from the depths of approximately 2 000 to 4 600 m,with the maximum pressure coefficient of 1.98 from drillstem tests(DST). Among the sonic,resistivity and density logs,sonic-log is the only reliable pressure indicator and can be used to predict the pore pressure with Eaton's method. All the overpressured mudstones in the source rock series have higher acoustic traveltimes compared with normally pressured mudstones at a given depth. The overpressured mudstones in the E(s3) and E(s4) units are characterized by a normal geothermal gradient,high average density values up to 2.5 g/cm^3,strong present-day hydrocarbon generation capability,abundant mature organic matter and high contents of residual hydrocarbons estimated by the Rock-Eval S1 values and chloroform-soluble bitumen "A" values. All suggest that the dominant mechanism for overpressure in the mudstones of source rock series in the Chezhen depression is hydrocarbon generation. A comparison between the matrix porosity of the normally pressured sandstones and overpressured sandstones,the quantitative evaluation of porosity loss caused by compaction and the conventional thin section inspection demonstrate that the sandstones in the Chezhen depression were normally compacted. The high contents of hydrocarbons in the overpressured reservoirs prove that the overpressure in the sandstones of the source rock series was caused by pressure transmission from the source rocks.展开更多
为降低紫外线对聚丙烯(Polyethylene,PP)非织造土工布的影响,选择ES(Ethylene-Propylene Side By Side)纤维和含有抗老化母粒的PP纤维为原料,TiO_(2)浸轧处理为后整理工序,采用针刺加固和热黏合加固技术制备了具有抗紫外老化功能的PP/E...为降低紫外线对聚丙烯(Polyethylene,PP)非织造土工布的影响,选择ES(Ethylene-Propylene Side By Side)纤维和含有抗老化母粒的PP纤维为原料,TiO_(2)浸轧处理为后整理工序,采用针刺加固和热黏合加固技术制备了具有抗紫外老化功能的PP/ES高强非织造土工布。研究了抗老化工艺对PP/ES土工布力学性能和抗紫外老化性能的影响。结果表明:添加抗老化母粒和TiO_(2)浸轧后整理的PP/ES土工布力学性能少许上升;该土工布紫外老化后的羰基吸收峰强度最弱,T 5%仅下降4.73℃,纵向和横向的断裂强度保留率仅下降26.55%和26.76%,表现出最佳的抗紫外老化性能。展开更多
基金support of the Department of Atomic Energy,Government of India,under project identification No.RT4002supported by Fermi vip Investigator grants NNX08AN56G,NNX08AN56G,NNX09AV10G,and NNX15AU81G。
文摘We present the results of the multi-epoch broadband spectral study of 1ES 2344+514 and study the evolution of physical parameters.We used nearly simultaneous data obtained from 2017 June 6 to 2022 August 6(MJD 57910–59797)in optical,UV,X-ray andγ-ray wavebands from various instruments including Swift-UVOT,Swift-XRT,Nuclear Spectroscopic Telescope Array(NuSTAR),AstroSat(SXT and LAXPC),Fermi-LAT,and TeV flux from MAGIC.During 2017 July,1ES 2344+514 appeared to be in the highest flaring state compared to other periods.We used the 0.5–7.0 keV and 3.0–20.0 keV data,respectively,from SXT and LAXPC of AstroSat and also 0.3–8.0 keV and 3.0–79.0 keV data,respectively,from Swift-XRT and NuSTAR.A joint fit between SXT and LAXPC,and between Swift-XRT and NuSTAR has been done for constraining the synchrotron peak.A clear shift in the synchrotron peak has been observed,which included 1ES 2344+514 in the HSP BL Lac family.A“harder-when-brighter”trend is observed in X-rays,and the opposite trend,i.e.,“softer-when-brighter,”is seen in theγ-rays.The multi-epoch broadband spectral energy distributions(SEDs)of this source were built and studied to get an idea of the radiation processes.The SEDs were fitted using a steady-state leptonic one-zone synchrotron+SSC model,and the fitted parameters of the emission region are consistent with those of other TeV BL Lacs.In this study,we found a weak correlation tendency between bolometric luminosity and magnetic field(B),as well as between bolometric luminosity and the break Lorentz factor(γ_(break)).
文摘为克服柔性传感器在灵敏度较低、生产流程复杂以及透气性不足等方面的挑战,本研究通过针刺-热熔技术制备了一种三维聚乙烯-聚丙烯(Ethylene-propylene side by side,ES)/聚酯(PET)纤维非织造材料。随后,利用碳纳米管(CNT)对该材料进行浸渍处理,成功开发了一种性能优异的CNT包覆三维ES/PET非织造基压力传感器,并对比分析了不同CNT浸渍时间和浸渍次数对传感器性能的影响。研究结果显示,该CNT包覆三维ES/PET非织造基柔性压力传感器具有高达0.375 kPa^(-1)的灵敏度和0~214.526 kPa的检测范围。经过2100次压缩循环,传感器展现了优异的稳定性和可重复性,响应时间为48 ms,恢复时间为122 ms。在实际应用中,该传感器能够精确识别如呼吸、吞咽、手指弯曲等人体细微生理活动,在运动、医疗、虚拟现实等多个领域具有潜在的广泛应用。
基金the National Natural Science Foundation of China(NSFC,Grant Nos.52176114 and 52306145)Natural Science Foundation of Jiangsu Province(Grant No.BK20230929)+3 种基金China Postdoctoral Science Foundation(Grant No.2023M731693)Fundamental Research Funds for the Central Universities,Grant No.30924010505Jiangsu Funding Program for Excellent Postdoctoral Talentthe Center of Analytical Facilities,Nanjing University of Science and Technology for providing technical equipment support for this article。
文摘To investigate the differences in combustion and energy release characteristics of metastable intermolecular composite materials composed of aluminum alloys and polyvinylidene fluoride(PVDF)with different compositions,two types of alloys were selected:Al-Mg and Al-Si.Pure aluminum powder of the same size was also chosen for comparison.The PVDF-coated metal particle composites and the mixtures of PVDF with metal particles were prepared using electrospray(ES)and physical blending methods(PM),respectively.A systematic study was conducted on the morphology,compositional structure,combustion performance,energy release characteristics,and thermal reactivity of the fabricated composites and their combustion products through scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDS),X-ray diffraction(XRD),combustion performance experiments,closed vessel pressure tests,and simultaneous thermogravimetric-differential scanning calorimetry(TG-DSC).The experimental results indicated that the PVDF-coated metal particles prepared by the electrospray method exhibited a distinct core-shell structure,with the metal particles in close contact with the PVDF matrix.Compared to the PM blended materials,the ES composites demonstrated superior combustion performance and energy release characteristics during combustion.Analysis of different metal fuel systems under identical preparation conditions revealed that Al-Mg and Al-Si fuels modulate the combustion and energy release properties of aluminum alloy-PVDF MICs through two distinct pathways.
基金supported by the Second Tibetan Plateau Scien-tific Expedition and Research Program(STEP)of China(Grant No.2019QZKK0402).
文摘Ecosystems play a pivotal role in advancing Sustainable Development Goals(SDGs)by providing indispensable and resilient ecosystem services(ESs).However,the limited analysis of spatiotemporal heterogeneity often re stricts the recognition of ESs’roles in attaining SDGs and landscape planning.We selected 183 counties in the Sichuan Province as the study area and mapped 10 SDGs and 7 ESs from 2000 to 2020.We used correlation analysis,principal component analysis,Geographically and Temporally Weighted Regression model,and self organizing maps to reveal the spatiotemporal heterogeneity of the impacts of the bundle of ESs on the SDGs and to develop spatial planning and management strategies.The results showed that(1)SDGs were improved in all counties,with SDG 1(No Poverty)and SDG 3(Good Health and Well-being)exhibiting poor performance.West ern Sichuan demonstrated stronger performance in environment-related SDGs in the Sichuan Province,while the Sichuan Basin showed better progress in socio-economic-related SDGs;(2)habitat quality,carbon sequestration,air pollution removal,and soil retention significantly influenced the development of 9 SDGs;(3)supporting,regulating,and provisioning service bundles have persistent and stable spatiotemporal heterogeneity effects on SDG1,SDG8,SDG11,SDG13,and SDG15.These findings substantiate the need for integrated management of multiple ESs and facilitate the regional achievement of SDGs in geographically intricate areas.
基金supported by the National Natural Science Foundation of China(21875076)the Guangdong Provincial International Joint Research Center for Energy Storage Materials(2023A0505090009)the Science and Technology Planning Project of Guangzhou City(2023B03J1278)。
文摘Electrolyte additives are pivotal for stable cycling of rechargeable sodium-ion batteries(SIBs),which dictate the creation of the protective interface film on electrodes.Cyclic sulfur-containing additives,such as1,3,2-dioxathiolane-2,2-dioxide(DTD),with the structure of sulfur surrounded by four oxygen atoms,have been proposed but less knowledge is available on the relationship between their molecular structures and interfacial stability.This work compares two similar molecule structure of cyclic sulfurcontaining additives,DTD and ethylene sulfite(ES),to investigate their effects on the electrochemical performance of NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM)||hard carbon(HC)pouch cells.Therein,ES with the structure of sulfur surrounded by three oxygen atoms,as electrolyte additive,is investigated in the SIBs for the first time.It is shown that adding 3.0%ES or 2.0%DTD(the optimal proportion)in the Control electrolyte(1 M NaPF_(6)in EC:EMC=3:7 with 5.0%FEC in weight)can improve cyclic stability and rate performance,respectively.Even under the high-temperature conditions,both ES and DTD exhibit good performance,but DTD is superior.Combinations of electrochemical methods,multi-spectroscopy,and theoretical calculations have been employed to evaluate and compare the effects of ES and DTD on sodium-ion battery.They reveal that ES and DTD can generate different content and composition by redox reaction on cathode and anode surface.The more and effective high-valence sulfur-containing components for DTD are the main reason to explain the better effect on DTD.This work shares new insights into the relationship between cyclic sulfur-containing additive molecule structure and electrolyte-electrode interface films effect,which fills the blanks of previous research.
文摘Background: Improving Water, Sanitation and Hygiene in health care settings is a critical prerequisite for achieving national health goals and Sustainable Development Goals (SDGs). The World Health Organization (WHO) has set a target for each United Nations member state to reach by 2030. Each member state is required to reach by 2022, 2025 and 2030 at least 60%, 80% and 100%, respectively of basic level of service of the five elements which are water, sanitation, hygiene, waste management and environmental cleaning. Methods: This study aimed to evaluate and document the current state of basic water, sanitation, and hygiene services in all lower-level health care facilities in the Dar es Salaam region of Tanzania as of July 2022. A cross-sectional study was conducted in 99 public dispensaries in the Dar es Salaam region’s five councils: Ubungo, Kigamboni, Kinondoni and Temeke Municipalities, and Ilala City. The interviewee form and observational checklists were both digitalized using the Kobo tool software. The respondents were health care facility in-charges or nurse in-charges. Data were downloaded, validated, and imported to Stata version 15 for analysis. Results: The basic WASH level per JMP is far below the target in 2022. Each member state by 2022 is required to reach at least 60% of the basic level of service of each element. We found a low coverage of basic WASH in the 99 dispensaries included in this study. The basic WASH coverage was met in only 10 (10.1%) of the dispensaries, while the remaining 89 (89.9%) dispensaries fall on limited WASH services. Conclusion: This study revealed lower coverage of basic WASH services in dispensaries. An urgent need is required to improve the status of WASH in all the dispensaries and facilitate the provision of quality health care services, patient safety and reduce health care associated infections.
基金sponsored by the China National Science and Technology Major Project (No. 2016ZX05006003-001)the Programme of Introducing Talents of Discipline to Universities (No. B14031)+1 种基金the National Natural Science Foundation of China (Nos. 41572114, 41302110)The SINOPEC Shengli Oilfield is thanked for providing background geological data and support
文摘The Chezhen depression,located in the south of Bohai Bay Basin,is an oil-producing basin in China. The third and fourth members of the Shahejie Formation(E(s3) and E(s4)) are the main source rock series in the Chezhen depression. Widespread overpressures occurred in the E(s3) and E(s4) from the depths of approximately 2 000 to 4 600 m,with the maximum pressure coefficient of 1.98 from drillstem tests(DST). Among the sonic,resistivity and density logs,sonic-log is the only reliable pressure indicator and can be used to predict the pore pressure with Eaton's method. All the overpressured mudstones in the source rock series have higher acoustic traveltimes compared with normally pressured mudstones at a given depth. The overpressured mudstones in the E(s3) and E(s4) units are characterized by a normal geothermal gradient,high average density values up to 2.5 g/cm^3,strong present-day hydrocarbon generation capability,abundant mature organic matter and high contents of residual hydrocarbons estimated by the Rock-Eval S1 values and chloroform-soluble bitumen "A" values. All suggest that the dominant mechanism for overpressure in the mudstones of source rock series in the Chezhen depression is hydrocarbon generation. A comparison between the matrix porosity of the normally pressured sandstones and overpressured sandstones,the quantitative evaluation of porosity loss caused by compaction and the conventional thin section inspection demonstrate that the sandstones in the Chezhen depression were normally compacted. The high contents of hydrocarbons in the overpressured reservoirs prove that the overpressure in the sandstones of the source rock series was caused by pressure transmission from the source rocks.
文摘为降低紫外线对聚丙烯(Polyethylene,PP)非织造土工布的影响,选择ES(Ethylene-Propylene Side By Side)纤维和含有抗老化母粒的PP纤维为原料,TiO_(2)浸轧处理为后整理工序,采用针刺加固和热黏合加固技术制备了具有抗紫外老化功能的PP/ES高强非织造土工布。研究了抗老化工艺对PP/ES土工布力学性能和抗紫外老化性能的影响。结果表明:添加抗老化母粒和TiO_(2)浸轧后整理的PP/ES土工布力学性能少许上升;该土工布紫外老化后的羰基吸收峰强度最弱,T 5%仅下降4.73℃,纵向和横向的断裂强度保留率仅下降26.55%和26.76%,表现出最佳的抗紫外老化性能。
