Using surface and balloon-sounding measurements, satellite retrievals, and ERA5 reanalysis during 2011–20, this study compares the precipitation and related wind dynamics, moisture and heat features in different area...Using surface and balloon-sounding measurements, satellite retrievals, and ERA5 reanalysis during 2011–20, this study compares the precipitation and related wind dynamics, moisture and heat features in different areas of the South China Sea(SCS) before and after SCS summer monsoon onset(SCSSMO). The rainy sea around Dongsha(hereafter simply referred to as Dongsha) near the north coast, and the rainless sea around Xisha(hereafter simply referred to as Xisha) in the western SCS, are selected as two typical research subregions. It is found that Dongsha, rather than Xisha, has an earlier and greater increase in precipitation after SCSSMO under the combined effect of strong low-level southwesterly winds, coastal terrain blocking and lifting, and northern cold air. When the 950-h Pa southwesterly winds enhance and advance northward, accompanied by strengthened moisture flux, there is a strong convergence of wind and moisture in Dongsha due to a sudden deceleration and rear-end collision of wind by coastal terrain blocking. Moist and warm advection over Dongsha enhances early and deepens up to 200 h Pa in association with the strengthened upward motion after SCSSMO, thereby providing ample moisture and heat to form strong precipitation. However, when the 950-h Pa southwesterly winds weaken and retreat southward, Xisha is located in a wind-break area where strong convergence and upward motion centers move in. The vertical moistening and heating by advection in Xisha enhance later and appear far weaker compared to that in Dongsha, consistent with later and weaker precipitation.展开更多
As a promising candidate electrode material in both Li-and Na-ion batteries(L/SIBs),the application of Co_(9)S_(8) is being hindered by its unsatisfactory electrochemical performance caused by the sluggish ion diffusi...As a promising candidate electrode material in both Li-and Na-ion batteries(L/SIBs),the application of Co_(9)S_(8) is being hindered by its unsatisfactory electrochemical performance caused by the sluggish ion diffusion kinetics and drastic volume expansion.Herein,a hybrid material composed of Co_(9)S_(8-x),N-doped carbon foam that seeded with Co nanoparticles(Co_(9)S_(8-x)@Co-NC) is constructed.Particularly,theoretical and experimental results imply that a built-in electric field at the interface of Co and NC is observed due to the variation of Fermi levels,forming rich Mott-Schottky-like heterointerfaces,which can significantly enhance the charge transfer capability between the active materials of Co_(9)S_(8) and conductive NC skeleton.Moreover,the sulfur defects in Co_(9)S_(8-x)can not only effectively lower the energy barrier of the ion diffusion and charge transfer processes,but also endow the target sample with more storage/adsorption/active sites for Li^(+)/Na^(+) ions,thus improving the rate performance of the Co_(9)S_(8-x)@Co-NC composite.As a result,the Co_(9)S_(8-x)@Co-NC exhibits fast surface-controlled redox kinetics and robust cycling stability.For instance,the Co_(9)S_(8-x)@Co-NC displays impressive Li-storage properties in both half and full cells with a high reversible capacity of 1007.4 mA h g^(-1)at 0.1 A g^(-1)after 100 cycles and superior rate capability up to 5 A g^(-1).Moreover,based on these comprehensive merits,the Co_(9)S_(8-x)@Co-NC composite shows decent electrochemical performance(472.2 and 311.1 mA h g^(-1)at 0.1 and 10 A g^(-1),respectively) as an anode for SIBs.This work presents an effective strategy for the construction of Mott-Schottky-like heterointerfaces in Co_(9)S_(8) based materials and provides specific inspiration for future works designing high-performance electrodes via interfacial engineering.展开更多
Fluorescence lifetime is not only associated with the molecular structure f fuorophores,but alsostrongly depends on the environment around them,which llows fuorescence lifetime imagingmicroscopy(FLIM)to be used as a t...Fluorescence lifetime is not only associated with the molecular structure f fuorophores,but alsostrongly depends on the environment around them,which llows fuorescence lifetime imagingmicroscopy(FLIM)to be used as a tool for precise measurement of the cell or tisue microenvironment,This review introduces the basic principle of fuorescence lifetime imagingtechnology and its application in clinical medicine,including research and diagnosis of diseases inskin,brain,eyes,mouth,bone,blood vessels and cavity organs,and drug evaluation.As anoninvasive,nontoxic and nonionizing radiation technique,FLIM demonstrates excellent per-formance with high sensitivity and specificity,which allows to determine precise position of thelesion and,thus,has good potential for application in biomedical research and clinical diagnosis.展开更多
In this work, we study existence theorem of the initial value problem for the system of fractional differential equations where Dα denotes standard Riemann-Liouville fractional derivative, 0 and A ?is a square matrix...In this work, we study existence theorem of the initial value problem for the system of fractional differential equations where Dα denotes standard Riemann-Liouville fractional derivative, 0 and A ?is a square matrix. At the same time, power-type estimate for them has been given.展开更多
In order to effectively use the ERA5 reanalysis data,observation data in and around Guangdong Province was used to evaluate the reanalysis data by analyzing the correlation coefficient and deviation. The results showe...In order to effectively use the ERA5 reanalysis data,observation data in and around Guangdong Province was used to evaluate the reanalysis data by analyzing the correlation coefficient and deviation. The results showed that among the surface elements,the sea level pressure and air temperature performed the best reproducibility,second the relative humidity and wind speed,and they had better performance in the Pearl River Delta and its surrounding areas,while the worst was wind direction. Except the relative humidity,elements had better performance at higher levels than lower levels among the ERA5 reanalysis upper-air data.展开更多
Supported Pd based catalysts are considered as the efficient candidates for low-carbon alkane oxidation for their outstanding capability to break C-H bond. Whereas, the irreversible deactivation of Pd based catalysts ...Supported Pd based catalysts are considered as the efficient candidates for low-carbon alkane oxidation for their outstanding capability to break C-H bond. Whereas, the irreversible deactivation of Pd based catalysts was still frequently observed. Herein, we reinforced the extruded Pd nanoparticles with quantitive Pt to assemble the evenly distributed Pd Pt nanoalloy onto ferrite perovskite(Pd Pt-LCF) matrix with strengthened robustness of metal/oxide support interface. We further co-achieved the enhanced performance, anti-overoxidation as well as resistance of vapor-poisoning in durability measurement. The operando X-ray photoelectron spectroscopy(O-XPS) combined with various morphology characterizations confirms that the accumulation of surface deep-oxidation species of Pd^(4+) is the culprit for fast activity loss in exsolved Pd system, especially at high temperature of 400 ℃. Conversely, it could be completely suppressed by in-situ alloying Pd with equal amount of Pt, which helps maintain the metastable Pd^(2+)/Pd shell and metallic solid-solution core structure. The density function theory(DFT) calculations further buttress that the dissociation of C–H was facilitated on alloy/perovskite interface which is, on the contrary, resistant toward O–H bond cleavage, as compared to Pd/perovskite. Our work suggests that the modification of exsolved metal/oxide catalytic interface could further enrich the toolkit of heterogeneous catalyst design.展开更多
Core-shell nanostructures consisting of active metal cores and protective shells often exhibit enhanced catalytic performance, in which reactants can access a small part of the core surfaces through the pores in the s...Core-shell nanostructures consisting of active metal cores and protective shells often exhibit enhanced catalytic performance, in which reactants can access a small part of the core surfaces through the pores in the shells. In this study, we show that Pt nanoparticles (NPs) can be embedded into few-layer hexagonal boron nitride (h-BN) overlayers, forming Pt@h-BN core-shell nanocatalysts. The h-BN shells not only protect the Pt NPs under harsh conditions but also allow gaseous molecules such as CO and 02 to access a large part of the Pt surfaces through a facile intercalation process. As a result, the Pt@h-BN nanostructures act as nanoreactors, and CO oxidation reactions with improved activity, selectivity, and stability occur at the core-shell interfaces. The confinement effect exerted by the h-BN shells promotes the Pt-catalyzed reactions. Our work suggests that two-dimensional shells can function as robust but flexible covers on nanocatalyst surfaces and tune the surface reactivity.展开更多
OBJECTIVE: To observe the clinical effect of Gushenyutai plaster administered at the Guanyuan(CV4) acupoint on male infertility associated with semen non-liquefaction.METHODS: Sixty-two male patients with infertility ...OBJECTIVE: To observe the clinical effect of Gushenyutai plaster administered at the Guanyuan(CV4) acupoint on male infertility associated with semen non-liquefaction.METHODS: Sixty-two male patients with infertility caused by semen non-liquefaction were random-ized into a treatment and control group. The control group received comprehensive therapy, which included oral administration of clarithromycin sustained release tablets, hip bath with Zhongyaoxiaoyan granules, prostate massage, and transurethral microwave treatment. The treatment group was administered Gushenyutai plaster in addition to the comprehensive therapy. Both groups were treated for 8 weeks. After treatment, the clinical effect and pregnancy rate were assessed and compared between the two groups.RESULTS: The effective rate of the treatment group was significantly higher than that of the control group(96.77% vs 70.97%, P<0.05) and the pregnancy rates of the treatment group and control groups were 38.71% and 16.13%, respectively(P<0.05).CONCLUSION: The effect of Gushenyutai plaster plus comprehensive therapy was better than that of the comprehensive therapy alone on male infertility induced by semen non-liquefaction.展开更多
Hybrid joints have better tensile properties than pure bonded and bolted bolts,and are increasingly used in the aerospace field.Tensile tests are carried out for the Hybrid Bonded/Bolted(HBB)joints of Carbon Fiber Rei...Hybrid joints have better tensile properties than pure bonded and bolted bolts,and are increasingly used in the aerospace field.Tensile tests are carried out for the Hybrid Bonded/Bolted(HBB)joints of Carbon Fiber Reinforced Polymer(CFRP)laminate and titanium alloy plate under different bolt numbers,and the corresponding load–displacement curves are obtained.At the same time,based on Continuum Damage Mechanics(CDM)theory,which is derived from 3D Hashin failure criteria,and a Cohesive Zone Model(CZM),the tensile strength prediction model of the composite laminate-titanium alloy plate multi-bolted HBB joint was established,and the numerical simulation results were in good agreement with the experimental height,which validate the feasibility of the model.The difference in the bearing capacity of HBB joints under different numbers of bolts is compared and analyzed.On this basis,the influence of inter-bolt distance on the tensile properties of the HBB joints is explored.The results show that the double-nail HBB joints can effectively improve the end warpage and low bearing capacity of the single-nail HBB joints.The tensile failure load of the double-nail HBB joints under the standard lap width(30 mm)is 82.6%higher than that of the single nail,the tensile failure load of the three-bolt HBB joints is 34.1%higher than that of the double nail.For the three-bolt HBB joint,the joint strength is controlled by the adhesive and the external bolt,while the internal bolt is redundant,the hybrid joint can be simplified by reducing the middle bolt.The inter-bolt distance has a great influence on the failure load of the hybrid joint.Increasing the inter-bolt distance can effectively improve the bearing capacity of the structure.展开更多
基金supported by a Guangdong Major Project of Basic and Applied Basic Research (Grant No.2020B0301030004)the Collaborative Observation and Multisource Real-time Data Fusion and Analysis Technology & Innovation team (Grant No.GRMCTD202103)the Foshan Special Project on Science and Technology in Social Field (Grant No.2120001008761)。
文摘Using surface and balloon-sounding measurements, satellite retrievals, and ERA5 reanalysis during 2011–20, this study compares the precipitation and related wind dynamics, moisture and heat features in different areas of the South China Sea(SCS) before and after SCS summer monsoon onset(SCSSMO). The rainy sea around Dongsha(hereafter simply referred to as Dongsha) near the north coast, and the rainless sea around Xisha(hereafter simply referred to as Xisha) in the western SCS, are selected as two typical research subregions. It is found that Dongsha, rather than Xisha, has an earlier and greater increase in precipitation after SCSSMO under the combined effect of strong low-level southwesterly winds, coastal terrain blocking and lifting, and northern cold air. When the 950-h Pa southwesterly winds enhance and advance northward, accompanied by strengthened moisture flux, there is a strong convergence of wind and moisture in Dongsha due to a sudden deceleration and rear-end collision of wind by coastal terrain blocking. Moist and warm advection over Dongsha enhances early and deepens up to 200 h Pa in association with the strengthened upward motion after SCSSMO, thereby providing ample moisture and heat to form strong precipitation. However, when the 950-h Pa southwesterly winds weaken and retreat southward, Xisha is located in a wind-break area where strong convergence and upward motion centers move in. The vertical moistening and heating by advection in Xisha enhance later and appear far weaker compared to that in Dongsha, consistent with later and weaker precipitation.
基金the financial support of the National Natural Science Foundation of China (51902089)the Educational Department of Jilin Province, China (JJKH20230587KJ)the Science and Technology Department of Jilin Province, China (20220101071JC)。
文摘As a promising candidate electrode material in both Li-and Na-ion batteries(L/SIBs),the application of Co_(9)S_(8) is being hindered by its unsatisfactory electrochemical performance caused by the sluggish ion diffusion kinetics and drastic volume expansion.Herein,a hybrid material composed of Co_(9)S_(8-x),N-doped carbon foam that seeded with Co nanoparticles(Co_(9)S_(8-x)@Co-NC) is constructed.Particularly,theoretical and experimental results imply that a built-in electric field at the interface of Co and NC is observed due to the variation of Fermi levels,forming rich Mott-Schottky-like heterointerfaces,which can significantly enhance the charge transfer capability between the active materials of Co_(9)S_(8) and conductive NC skeleton.Moreover,the sulfur defects in Co_(9)S_(8-x)can not only effectively lower the energy barrier of the ion diffusion and charge transfer processes,but also endow the target sample with more storage/adsorption/active sites for Li^(+)/Na^(+) ions,thus improving the rate performance of the Co_(9)S_(8-x)@Co-NC composite.As a result,the Co_(9)S_(8-x)@Co-NC exhibits fast surface-controlled redox kinetics and robust cycling stability.For instance,the Co_(9)S_(8-x)@Co-NC displays impressive Li-storage properties in both half and full cells with a high reversible capacity of 1007.4 mA h g^(-1)at 0.1 A g^(-1)after 100 cycles and superior rate capability up to 5 A g^(-1).Moreover,based on these comprehensive merits,the Co_(9)S_(8-x)@Co-NC composite shows decent electrochemical performance(472.2 and 311.1 mA h g^(-1)at 0.1 and 10 A g^(-1),respectively) as an anode for SIBs.This work presents an effective strategy for the construction of Mott-Schottky-like heterointerfaces in Co_(9)S_(8) based materials and provides specific inspiration for future works designing high-performance electrodes via interfacial engineering.
基金funded by the Science and Technology Planning Fundamental Research Project of Shenzhen(No.JCYJ20150324140036853)National Natural Science Foundation of China(No.61378091)+1 种基金Ningbo Natural Science Foundation Project(No.2016A610032)the Central University Basic Scientic Research Business Expenses Project(No.NSIY051405).
文摘Fluorescence lifetime is not only associated with the molecular structure f fuorophores,but alsostrongly depends on the environment around them,which llows fuorescence lifetime imagingmicroscopy(FLIM)to be used as a tool for precise measurement of the cell or tisue microenvironment,This review introduces the basic principle of fuorescence lifetime imagingtechnology and its application in clinical medicine,including research and diagnosis of diseases inskin,brain,eyes,mouth,bone,blood vessels and cavity organs,and drug evaluation.As anoninvasive,nontoxic and nonionizing radiation technique,FLIM demonstrates excellent per-formance with high sensitivity and specificity,which allows to determine precise position of thelesion and,thus,has good potential for application in biomedical research and clinical diagnosis.
文摘In this work, we study existence theorem of the initial value problem for the system of fractional differential equations where Dα denotes standard Riemann-Liouville fractional derivative, 0 and A ?is a square matrix. At the same time, power-type estimate for them has been given.
基金Supported by the Science and Technology Research Project of Guangdong Meteorological Service(GRMC2018M17)。
文摘In order to effectively use the ERA5 reanalysis data,observation data in and around Guangdong Province was used to evaluate the reanalysis data by analyzing the correlation coefficient and deviation. The results showed that among the surface elements,the sea level pressure and air temperature performed the best reproducibility,second the relative humidity and wind speed,and they had better performance in the Pearl River Delta and its surrounding areas,while the worst was wind direction. Except the relative humidity,elements had better performance at higher levels than lower levels among the ERA5 reanalysis upper-air data.
基金supported by the National Natural Science Foundation of China (Nos.22272136, 22202041, 22102135, 22202163,22172129)the Fundamental Research Funds for the Central Universities (No.20720220119)+3 种基金Science and Technology Project of Fujian Province (No.2022L3077)the financial support from Guangdong Basic and Applied Basic Research Fund (No.2022A1515110239)the funds from Science and Technology Projects of Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM)(No.HRTP-[2022]-3)the Fundamental Research Funds for the Central Universities (No.20720220008)。
文摘Supported Pd based catalysts are considered as the efficient candidates for low-carbon alkane oxidation for their outstanding capability to break C-H bond. Whereas, the irreversible deactivation of Pd based catalysts was still frequently observed. Herein, we reinforced the extruded Pd nanoparticles with quantitive Pt to assemble the evenly distributed Pd Pt nanoalloy onto ferrite perovskite(Pd Pt-LCF) matrix with strengthened robustness of metal/oxide support interface. We further co-achieved the enhanced performance, anti-overoxidation as well as resistance of vapor-poisoning in durability measurement. The operando X-ray photoelectron spectroscopy(O-XPS) combined with various morphology characterizations confirms that the accumulation of surface deep-oxidation species of Pd^(4+) is the culprit for fast activity loss in exsolved Pd system, especially at high temperature of 400 ℃. Conversely, it could be completely suppressed by in-situ alloying Pd with equal amount of Pt, which helps maintain the metastable Pd^(2+)/Pd shell and metallic solid-solution core structure. The density function theory(DFT) calculations further buttress that the dissociation of C–H was facilitated on alloy/perovskite interface which is, on the contrary, resistant toward O–H bond cleavage, as compared to Pd/perovskite. Our work suggests that the modification of exsolved metal/oxide catalytic interface could further enrich the toolkit of heterogeneous catalyst design.
基金Acknowledgements This work was financially supported by the National Natural Science Foundation of China (Nos. 21373208, 91545204, 21688102, and 21621063), and Ministry of Science and Technology of China (Nos. 2016YFA0200200, 2013CB834603, and 2013CB933100), and the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDB17020200).
文摘Core-shell nanostructures consisting of active metal cores and protective shells often exhibit enhanced catalytic performance, in which reactants can access a small part of the core surfaces through the pores in the shells. In this study, we show that Pt nanoparticles (NPs) can be embedded into few-layer hexagonal boron nitride (h-BN) overlayers, forming Pt@h-BN core-shell nanocatalysts. The h-BN shells not only protect the Pt NPs under harsh conditions but also allow gaseous molecules such as CO and 02 to access a large part of the Pt surfaces through a facile intercalation process. As a result, the Pt@h-BN nanostructures act as nanoreactors, and CO oxidation reactions with improved activity, selectivity, and stability occur at the core-shell interfaces. The confinement effect exerted by the h-BN shells promotes the Pt-catalyzed reactions. Our work suggests that two-dimensional shells can function as robust but flexible covers on nanocatalyst surfaces and tune the surface reactivity.
基金the Science and Technology Planning for social development Project of Guangdong Province[Guangdong S&T Planning(2011)No.71]the Construction of Chinese Medicine Strong Province Project supported by Administration of Traditional Chinese Medicine of Guangdong Province[Guangdong TCM(2012)No.23]The Social Development Project of Shantou[Shantou Finance(2010)No.480]
文摘OBJECTIVE: To observe the clinical effect of Gushenyutai plaster administered at the Guanyuan(CV4) acupoint on male infertility associated with semen non-liquefaction.METHODS: Sixty-two male patients with infertility caused by semen non-liquefaction were random-ized into a treatment and control group. The control group received comprehensive therapy, which included oral administration of clarithromycin sustained release tablets, hip bath with Zhongyaoxiaoyan granules, prostate massage, and transurethral microwave treatment. The treatment group was administered Gushenyutai plaster in addition to the comprehensive therapy. Both groups were treated for 8 weeks. After treatment, the clinical effect and pregnancy rate were assessed and compared between the two groups.RESULTS: The effective rate of the treatment group was significantly higher than that of the control group(96.77% vs 70.97%, P<0.05) and the pregnancy rates of the treatment group and control groups were 38.71% and 16.13%, respectively(P<0.05).CONCLUSION: The effect of Gushenyutai plaster plus comprehensive therapy was better than that of the comprehensive therapy alone on male infertility induced by semen non-liquefaction.
基金co-supported by the National Natural Science Foundation of China(No.U1833116)Key Scientific Research Project of Colleges and Universities in Henan Province,China(No.20A460023)。
文摘Hybrid joints have better tensile properties than pure bonded and bolted bolts,and are increasingly used in the aerospace field.Tensile tests are carried out for the Hybrid Bonded/Bolted(HBB)joints of Carbon Fiber Reinforced Polymer(CFRP)laminate and titanium alloy plate under different bolt numbers,and the corresponding load–displacement curves are obtained.At the same time,based on Continuum Damage Mechanics(CDM)theory,which is derived from 3D Hashin failure criteria,and a Cohesive Zone Model(CZM),the tensile strength prediction model of the composite laminate-titanium alloy plate multi-bolted HBB joint was established,and the numerical simulation results were in good agreement with the experimental height,which validate the feasibility of the model.The difference in the bearing capacity of HBB joints under different numbers of bolts is compared and analyzed.On this basis,the influence of inter-bolt distance on the tensile properties of the HBB joints is explored.The results show that the double-nail HBB joints can effectively improve the end warpage and low bearing capacity of the single-nail HBB joints.The tensile failure load of the double-nail HBB joints under the standard lap width(30 mm)is 82.6%higher than that of the single nail,the tensile failure load of the three-bolt HBB joints is 34.1%higher than that of the double nail.For the three-bolt HBB joint,the joint strength is controlled by the adhesive and the external bolt,while the internal bolt is redundant,the hybrid joint can be simplified by reducing the middle bolt.The inter-bolt distance has a great influence on the failure load of the hybrid joint.Increasing the inter-bolt distance can effectively improve the bearing capacity of the structure.