This thesis discusses the earthquake reflecting ability of the observation well pattern system of Jiangsu Province, China, which has been digitally renovated, and probes into the cause of the major differences in the ...This thesis discusses the earthquake reflecting ability of the observation well pattern system of Jiangsu Province, China, which has been digitally renovated, and probes into the cause of the major differences in the earthquake reflecting abilities of well holes at different measurement points. This is achieved through the analysis of the co-seismic responses to the Wenchuan (2008; Ms8.0, China) and Tohoku (2011; Ms9.0, Japan) earthquakes. We found that the co-seismic response of water level from regional well holes in Jiangsu Province was stronger than that of water temperature. The water-level co-seismic response follows a consistent law and is closely related to the earthquake magnitude. The co-seismic response of water temperature strongly varied among well points, and was more often manifested as a slow restorative change. The co-seismic responses also varied based on tectonic elements. The response in central and northern Jiangsu was weaker than that of southern Jiangsu, possibly due to the thicker loess cover layer in central Jiangsu which makes it less effective at capturing the micro-changes of stress-strain states relative to the hilly land in the south. The more complicated geological structure in southern Jiangsu makes it contribute to greater changes in the state of underground water after a minor disturbance.展开更多
As lithium-ion batteries(LIBs)continue to evolve toward lower costs and higher energy densities,their potential safety risks have become increasingly apparent.Incidents such as explosions at energy storage facilities,...As lithium-ion batteries(LIBs)continue to evolve toward lower costs and higher energy densities,their potential safety risks have become increasingly apparent.Incidents such as explosions at energy storage facilities,fires in electric vehicles,and building fires ignited by charging two-wheeled vehicles have been occurring with alarming frequency,often resulting in significant casualties and injuries.Conducting indepth investigations into thermal runaway(TR)incidents in LIBs can significantly reduce the risk of future occurrences.However,current investigations into LIB fire and explosion incidents face challenges due to the difficulty of conducting in-depth analyses and the lack of a robust theoretical framework to guide these investigations.To enhance the effectiveness of in-depth investigations into battery fire and explosion incidents and to address the lack of theoretical guidance,this paper is the first to systematically examine the conservation and flow patterns of elements during the TR process of LIBs.The analysis reveals that during TR,the gas products generated include approximately 1.5 g of H_(2),23.6 g of CO,88.4 g of CO_(2),8.9 g of C_(2)H_(4),7.3 g of CH_(4),3.7 g of C_(2)H_(6),and 82 g of electrolyte vapor.After TR,the solid compounds formed consist of approximately 2.5 g of LiF,29–92.2 g of elemental Ni/Co/Mn,11.4 g of Li_(2)CO_(3),200.6 g of graphite,1.4 g of NiO,29.6 g of MnO,30.1 g of CoO,67 g of elemental Cu,0.03 g of LiNiO_(2),and 4.3 g of LiAlO_(2).Importantly,the energy released from reactions forming solid compounds during TR surpasses that from gas-forming reactions.This investigation represents the first application of Hess’s law to verify the conservation of elements during the TR process of lithium-ion batteries.The proposed methodology is also applicable to other types of energy storage batteries,effectively advancing techniques for comprehensively investigating lithium battery fire and explosion incidents.展开更多
BACKGROUND Data regarding complex Crohn’s perianal fistulas(CPF)epidemiology are limited,and optimal treatment strategies are elusive.An improved understanding of how CPF treatment options are used in the real-world ...BACKGROUND Data regarding complex Crohn’s perianal fistulas(CPF)epidemiology are limited,and optimal treatment strategies are elusive.An improved understanding of how CPF treatment options are used in the real-world setting and factors associated with CPF development,treatment failure,and reasons for undergoing multiple surgeries may help to inform optimal patient management strategies,reduce treatment burden,and improve outcomes in patients with CPF.AIM To describe the epidemiology,treatments,outcomes,and associated risk/protective factors for complex CPF.METHODS Electronic databases(MEDLINE,EMBASE,EBM Reviews,EconLit)were searched.Two reviewers independently used populations,interventions,comparators,outcomes,study designs,and time criteria to identify relevant studies.Observational studies published in English from January 1,2015 to February 17,2022 with>50 patients were included,even if complex CPF was not defined.Items of interest included complex CPF definitions,epidemiology,treatment patterns,morbidity,mortality,and risk factors associated with complex CPF development,treatment failure,and undergoing multiple surgeries.Data were reported using descriptive statistics.RESULTS Overall,140 studies were included.Complex CPF definitions were heterogeneous and rarely reported(24 studies).Hence,data mostly related to CPF in general.CPF prevalence was variable(range:1.5%-81.0%).Incidence was wide-ranging and mostly reported cumulatively at 1-year post-Crohn’s disease diagnosis(range:3.5%-50.1%).Overall healing and failure rates after treatment were in the range of 10.5%-80.2%and 3.6%-83.0%,respectively.Abscesses were the most frequently reported morbidity(n=18).No CPF-related deaths were reported.No consistent risk or protective factors were identified.CONCLUSION Epidemiology,treatment patterns,and risk factors for CPF vary,likely due to inconsistent CPF and clinical outcome definitions.Standardization would facilitate comparability,which may inform optimal complex CPF treatment strategies.展开更多
In wind and solar renewable-dominant hybrid alternating current/direct current(AC/DC)power systems,the active power of high-voltage direct current(HVDC)system is significantly limited by the security and stability eve...In wind and solar renewable-dominant hybrid alternating current/direct current(AC/DC)power systems,the active power of high-voltage direct current(HVDC)system is significantly limited by the security and stability events caused by cascading failures.To identify critical lines in cascading failures,a rapid risk assessment method is proposed based on the gradient boosting decision tree(GBDT)and frequent pat-tern growth(FP-Growth)algorithms.First,security and stability events triggered by cascading failures are analyzed to explain the impact of cascading failures on the maximum DC power.Then,a cascading failure risk index is defined,focusing on the DC power being limited.To handle the strong nonlinear relationship between the maximum DC power and cascading failures,a GBDT with an update strategy is utilized to rapidly predict the maximum DC power under uncertain operating conditions.Finally,the FP-Growth algorithm is improved to mine frequent patterns in cascading failures.The importance index for each fault in a frequent pattern is defined by evaluating its impact on cascading failures,enabling the identification of critical lines.Simulation results of a modified Ningxia–Shandong hybrid AC/DC system in China demonstrate that the proposed method can rapidly assess the risk of cascading failures and effectively identify critical lines.展开更多
This paper considers the short-range sensing imple-mentation in continuous-wave(CW)phased array systems.We specifically address this CW short-range sensing challenges stemming from the self-interference cancellation(S...This paper considers the short-range sensing imple-mentation in continuous-wave(CW)phased array systems.We specifically address this CW short-range sensing challenges stemming from the self-interference cancellation(SIC)operation and synthesis requirement of arbitrary beampatterns for the sensing purpose,which has rarely been researched before.In this paper,unlike the only existed work that exploits the heuris-tic method and shares no analytical solution,an SIC pattern syn-thesis design is presented with a closed-form solution.By utiliz-ing the null-space projection(NSP)method,the proposed method effectively mitigates the self-interference to enable the in-band full-duplex operation of the array system.Subsequently,the NSP design will be innovatively embedded in a singular value decomposition(SVD)based weighted alternating reserve projec-tion(WARP)approach to efficiently synthesize an arbitrary desired pattern by solving a unique rank-deficient weighted least mean square problem.Numerical results validate the effective-ness of the proposed method in terms of beampattern,SIC per-formance,and sensing performance.展开更多
Erectile dysfunction(ED)is prevalent among men,but its relationship with dietary habits is uncertain.The aim of our study was to assess whether dietary patterns enhance erectile function by reviewing the literature pu...Erectile dysfunction(ED)is prevalent among men,but its relationship with dietary habits is uncertain.The aim of our study was to assess whether dietary patterns enhance erectile function by reviewing the literature published before August 1,2022,via PubMed,Web of Science,and EMBASE databases.The data compiled included author details;publication dates,countries,treatments,patient numbers,ages,follow-ups,and clinical trial outcomes,such as ED cases,odds ratios(ORs),confidence intervals(CIs),and International Index of Erectile Function-5(IIEF-5)scores with means and standard deviations.An analysis of 14 studies with 27389 participants revealed that plant-based diets(OR=0.71,95%CI:0.66-0.75;P<0.00001),low-fat diets(OR=0.27,95%CI:0.13-0.53;P=0.0002),and alternative diets such as intermittent fasting and organic diets(OR=0.54,95%CI:0.36-0.80;P=0.002)significantly reduced ED risk.High-protein low-fat diets(hazard ratio[HR]=1.38,95%CI:1.12-1.64;P<0.00001)and high-carb low-fat diets(HR=0.79,95%CI:0.55-1.04;P<0.00001)improved IIEF-5 scores.Combined diet and exercise interventions decreased the likelihood of ED(OR=0.49,95%CI:0.28-0.85;P=0.01)and increased the IIEF-5 score(OR=3.40,95%CI:1.69-5.11;P<0.0001).Diets abundant in fruits and vegetables(OR=0.97,95%CI:0.96-0.98;P<0.00001)and nuts(OR=0.54,95%CI:0.37-0.80;P=0.002)were also correlated with lower ED risk.Our meta-analysis underscores a strong dietary-ED association,suggesting that low-fat/Mediterranean diets rich in produce and nuts could benefit ED management.展开更多
The Yellow River Delta(YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the regio...The Yellow River Delta(YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the region has witnessed significant land use/cover changes(LUCC), impacting ecosystem services(ES) and ecological security patterns(ESP). Investigating LUCC's effects on ES and ESP in the YRD is crucial for ecological security and sustainable development. This study utilized the PLUS model to simulate 2030 land use scenarios, including natural development(NDS), economic development(EDS), and ecological protection scenarios(EPS). Subsequently, the InVEST model and circuit theory were applied to assess ES and ESP under varying LUCC scenarios from 2010 to 2030. Findings indicate:(1) Notable LUCC from 2010 to 2030, marked by decreasing cropland and increasing construction land and water bodies.(2) From 2010 to 2020, improvements were observed in carbon storage,water yield, soil retention, and habitat quality, whereas 2020–2030 saw increases in water yield and soil retention but declines in habitat quality and carbon storage. Among the scenarios, EPS showed superior performance in all four ES.(3) Between 2010 and 2030, ecological sources, corridors, and pinchpoints expanded, displaying significant spatial heterogeneity. The EPS scenario yielded the most substantial increases in ecological sources,corridors, and pinchpoints, totaling 582.89 km^(2), 645.03 km^(2),and 64.43 km^(2), respectively. This study highlights the importance of EPS, offering insightful scientific guidance for the YRD's sustainable development.展开更多
The objectives of this study were to assess distribution patterns of plant species richness,plant diversity and vegetation structure in relation to environmental factors along elevation gradient in Al-Jabal Al-Akhdar,...The objectives of this study were to assess distribution patterns of plant species richness,plant diversity and vegetation structure in relation to environmental factors along elevation gradient in Al-Jabal Al-Akhdar,Libya.For each species,its growth form,chorological affinities,degree of occurrence,endemism status and originality were provided.A total of 534 taxa were generated from 70 families of the flowering plants,and 3 of the non-flowering plants were identified.The native flora of the study area was counted for 80.2%of the total indigenous taxa(465).The hump-shaped pattern of plant species richness was obtained,with the highest species richness at the mid-elevations,and both ends of the gradient have the lowest.The annuals(300 species,56.2%)and non-succulent perennial herbs(165 species,30.9%)were the most dominant growth forms of the total species composition.Along the elevation gradient,Asteraceae,Fabaceae,Poaceae,Lamiaceae and Apiaceae were the dominant families with the highest numbers of species.This investigation recorded 31 endemic taxa,comprising 25 dicots and 6 monocots,primarily of Mediterranean origin,with most belonging to the Asteraceae and Lamiaceae families.Mediterranean chorotype was the dominant,whether pure(mono-),or combined with one(bi-and pluri-regional)or more(pluri-regional).Application of cluster analysis on the vegetation data yielded four cluster groups;each was linked to an elevation level.It emphasized the importance of establishing conservation strategies to minimize human disturbance and safeguard relic habitats of Juniperus phoenicea L.at its southern distribution limits in Africa,underlining the proactive management required for species preservation.The application of Redundancy Analysis revealed that Shannon diversity index(H'),pH and Fe were the determinant soil factor in the mid-elevation levels(L2 and L3)whereas altitude,fine sand,HCO3,OM,and soil contents of Na,SO4 and Cl for the extreme levels(L1 and L4).展开更多
Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradient...Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradients in subalpine meadow ecosystems. To reveal the elevational patterns of warming effects on plant biodiversity, community structure, productivity, and soil properties, we conducted a warming experiment using open-top chambers from August 2019 to August 2022 at high(2764 m a. s. l.), medium(2631 m a. s. l.), and low(2544 m a. s. l.) elevational gradients on a subalpine meadow slope of Mount Wutai, Northern China. Our results showed that three years of warming significantly increased topsoil temperature but significantly decreased topsoil moisture at all elevations(P<0.05), and the percentage of increasing temperature and decreasing moisture both gradually raised with elevation lifting. Warming-induced decreasing proportions of soil organic carbon(SOC, by 19.24%), and total nitrogen(TN, by 24.56%) were the greatest at high elevational gradients. Experimental warming did not affect topsoil C: N, p H, NO_(3)^(-)-N, or NH_(4)^(+)-N at the three elevational gradients. Warming significantly increased species richness(P<0.01) and Shannon-Weiner index(P<0.05) at low elevational gradients but significantly decreased belowground biomass(P<0.05) at a depth of 0–10 cm at three elevational gradients. Warming caused significant increases in the aboveground biomass in the three elevational plots. Warming significantly increased the aboveground biomass of graminoids in medium(by 92.47%) and low(by 98.25%) elevational gradients, that of sedges in high(by 72.44%) and medium(by 57.16%) elevational plots, and that of forbs in high(by 75.88%), medium(by 34.38%), and low(by 74.95%) elevational plots. Species richness had significant linear correlations with SOC, TN, and C: N(P<0.05), but significant nonlinear responses to soil temperature and soil moisture in the warmed treatment(P<0.05). The warmed aboveground biomass had a significant nonlinear response to soil temperature and significant linear responses to soil moisture(P<0.05). This study provided evidence that altitude is a factor in sensitivity to climate warming, and these different parameters(e.g., plant species richness, Shannon-Weiner index, soil temperature, soil moisture, SOC, and TN) can be used to measure this sensitivity.展开更多
A prediction framework based on the evolution of pattern motion probability density is proposed for the output prediction and estimation problem of non-Newtonian mechanical systems,assuming that the system satisfies t...A prediction framework based on the evolution of pattern motion probability density is proposed for the output prediction and estimation problem of non-Newtonian mechanical systems,assuming that the system satisfies the generalized Lipschitz condition.As a complex nonlinear system primarily governed by statistical laws rather than Newtonian mechanics,the output of non-Newtonian mechanics systems is difficult to describe through deterministic variables such as state variables,which poses difficulties in predicting and estimating the system’s output.In this article,the temporal variation of the system is described by constructing pattern category variables,which are non-deterministic variables.Since pattern category variables have statistical attributes but not operational attributes,operational attributes are assigned to them by posterior probability density,and a method for analyzing their motion laws using probability density evolution is proposed.Furthermore,a data-driven form of pattern motion probabilistic density evolution prediction method is designed by combining pseudo partial derivative(PPD),achieving prediction of the probability density satisfying the system’s output uncertainty.Based on this,the final prediction estimation of the system’s output value is realized by minimum variance unbiased estimation.Finally,a corresponding PPD estimation algorithm is designed using an extended state observer(ESO)to estimate the parameters to be estimated in the proposed prediction method.The effectiveness of the parameter estimation algorithm and prediction method is demonstrated through theoretical analysis,and the accuracy of the algorithm is verified by two numerical simulation examples.展开更多
AIM:To determine the smartphone use patterns and effects of smartphone use on accommodation and convergence system of the eyes among Malaysian teenagers.METHODS:A total of 62 participants aged between 13 and 17y were ...AIM:To determine the smartphone use patterns and effects of smartphone use on accommodation and convergence system of the eyes among Malaysian teenagers.METHODS:A total of 62 participants aged between 13 and 17y were involved.A self-administered questionnaires containing 12 items was used to evaluate the smartphone usage patterns.This was followed by an eye examination,involving a battery of accommodation and convergence assessments before and after the smartphone use.The data analysis comprised descriptive statistics,paired t-test,and correlation coefficients.RESULTS:The use of smartphones is at a high level and at an optimal distance daily,with more than 6h a day watching video films,games,and completing school projects.Majority of the participants not reported eye strain factors and eye prescription changes with the use of digital devices.The use of a smartphone continuously for 30min was found to significantly decrease amplitude of accommodation,accommodative facility,and positive relative accommodation(P<0.001).Meanwhile,the lag of accommodation parameters and negative relative accommodation increased with the use of smartphones significantly(P<0.001).The near point of convergence(NPC)and distance and near negative fusional vergence decreased significantly(P<0.001).The NPC parameter was found to have a weak negative association with the frequency of smartphone use(R=-0.276,P<0.05).CONCLUSION:Frequent and continuous use of smartphones have increased visual stress and resulted in weakness of accommodation and vergence functions.Therefore,frequent break is mandatory when using a smartphone and appropriate visual hygiene,the 20-20-20 rule(every 20min,view something 20 feet away for 20s)are required during smartphone use to maintain visual function.展开更多
Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns(SWPs),however,the consistency of different classification methods is rarely examine...Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns(SWPs),however,the consistency of different classification methods is rarely examined.In this study,we apply two widely-used objective methods,the self-organizing map(SOM)and K-means clustering analysis,to derive ozone-favorable SWPs at four Chinese megacities in 2015-2022.We find that the two algorithms are largely consistent in recognizing dominant ozone-favorable SWPs for four Chinese megacities.In the case of classifying six SWPs,the derived circulation fields are highly similar with a spatial correlation of 0.99 between the two methods,and the difference in themean frequency of each SWP is less than 7%.The six dominant ozone-favorable SWPs in Guangzhou are all characterized by anomaly higher radiation and temperature,lower cloud cover,relative humidity,and wind speed,and stronger subsidence compared to climatology mean.We find that during 2015-2022,the occurrence of ozone-favorable SWPs days increases significantly at a rate of 3.2 days/year,faster than the increases in the ozone exceedance days(3.0 days/year).The interannual variability between the occurrence of ozone-favorable SWPs and ozone exceedance days are generally consistent with a temporal correlation coefficient of 0.6.In particular,the significant increase in ozone-favorable SWPs in 2022,especially the Subtropical High type which typically occurs in September,is consistent with a long-lasting ozone pollution episode in Guangzhou during September 2022.Our results thus reveal that enhanced frequency of ozone-favorable SWPs plays an important role in the observed 2015-2022 ozone increase in Guangzhou.展开更多
The preparation of red,green,and blue quantum dot(QD)pixelated arrays with high precision,resolution,and brightness poses a significant challenge on the development of advanced micro-displays for virtual,augmented,and...The preparation of red,green,and blue quantum dot(QD)pixelated arrays with high precision,resolution,and brightness poses a significant challenge on the development of advanced micro-displays for virtual,augmented,and mixed reality applications.Alongside the controlled synthesis of high-performance QDs,a reliable QD patterning technology is crucial in overcoming this challenge.Among the various methods available,photolithography-based patterning technologies show great potentials in producing ultra-fine QD patterns at micron scale.This review article presents the recent advancements in the field of QD patterning using photolithography techniques and explores their applications in micro-display technology.Firstly,we discuss QD patterning through photolithography techniques employing photoresist(PR),which falls into two categories:PRassisted photolithography and photolithography of QDPR.Subsequently,direct photolithography techniques based on photo-induced crosslinking of photosensitive groups and photo-induced ligand cleavage mechanisms are thoroughly reviewed.Meanwhile,we assess the performance of QD arrays fabricated using these photolithography techniques and their integration into QD light emitting diode display devices as well as color conversionbased micro light emitting diode display devices.Lastly,we summarize the most recent developments in this field and outline future prospects.展开更多
The Hengduan Mountains,situated on the southeastern edge of the Qinghai-Tibet Plateau,are the longest and widest north-south-oriented mountain range in China,exerting a significant influence on the ecological and geog...The Hengduan Mountains,situated on the southeastern edge of the Qinghai-Tibet Plateau,are the longest and widest north-south-oriented mountain range in China,exerting a significant influence on the ecological and geographical pattern.Understanding the topographic and geomorphological characteristics of the Hengduan Mountains is fundamental and crucial for research in related fields such as ecology,geography,and sustainability.In this study,Digital Elevation Model(DEM)data were utilized to extract and analyze the topography and geomorphology(TG)pattern.TG maps have been developed to quantitatively classify the TG types in the Hengduan Mountains by combining the five factors of elevation,slope,aspect,relief and landform.The spatial distribution and quantitative characteristics of these factors were mapped and investigated using geographic information systems.The results revealed that:(1)The Hengduan Mountains exhibit an elongated north-south distribution,with an average elevation of approximately 3746 m,an average slope of around 25°,and an average relief of about 266 m.(2)The Hengduan Mountains display significant elevation differences,with an overall high elevation,characterized by a trend of lower elevation in the east and higher elevation in the west,as well as irregular orientations of various aspects.(3)The 19 landform types were identified,the landform types of the Hengduan Mountains are primarily composed of low-relief high-mountains(42.0618%),low-relief mid-mountains(22.4624%),and high-elevation hills(20.5839%).The results of the study can provide data and information support for the ecology,environmental protection and sustainable development of the Hengduan Mountains.展开更多
Rock fractures or faults could be reactivated by the thermal stress generated during the decay process of the high-level radioactive waste in deep geological repositories(DGRs).Understanding thermoshearing behavior an...Rock fractures or faults could be reactivated by the thermal stress generated during the decay process of the high-level radioactive waste in deep geological repositories(DGRs).Understanding thermoshearing behavior and its influencing factors are important for the long-term performance assessment of DGRs.We designed multistage mechanical(M)shear tests and thermomechanical(TM)shear tests on three 100 mm-cubic granite specimens,each containing a single inclined sawcut fracture with distinct microroughness of 8-15μm.M test results have shown that the static friction coefficient of the granite fracture decreases in proportion to the increase in the logarithm of the loading rate within the range of 1-15 kPa/s.For the given heating and boundary conditions,thermal loading rate,i.e.,thermal stress increment with heating time,is measured to be around 1 kPa/s in the fractured granite.Thermoshearing can be well predicted by the linear Mohr-Coulomb failure envelope deduced from M shear tests employing a loading rate that is comparable with the thermal loading rate.The granite fractures exhibited two distinct slip patterns during the mechanical shearing,i.e.,stick-slip observed in the smooth fracture and stable sliding in the relatively rough surface.In contrast,the mechanical loading rate(1-15 kPa/s)investigated in this study appears to not influence the slip pattern.Unlike those in M shear tests,thermoshearing in both smooth and relatively rough fractures show stable sliding with a very slow peak velocity of around 0.002μm/s.展开更多
In the era of the digital economy,digital trade has demonstrated strong vitality,becoming a crucial driving force for the highquality development of national and regional economies.However,understanding the resilience...In the era of the digital economy,digital trade has demonstrated strong vitality,becoming a crucial driving force for the highquality development of national and regional economies.However,understanding the resilience of digital trade in the face of external crises is an important topic.Taking the backdrop of Sino-US trade friction,this paper constructs a resilience index system for digital trade.It utilizes entropy method,kernel density estimation,and ArcGIS mapping to calculate and visually analyze the resilience of China’s digital trade from 2017 to 2021.Additionally,a Tobit model is constructed to explore the main influencing factors of digital trade resilience patterns.The research findings indicate:1)temporally,during the period of Sino-US trade friction,China’s digital trade resilience shows an overall upward trend,but there are regional differences in resilience levels across the country,with a severe polarization phenomenon.2)Spatially,high resilience is observed in the eastern and central regions of China,while the western and northeastern regions exhibit low resilience.3)From a dimensional perspective,the resistance of digital trade resilience displays a spatial distribution of high values in the east and low values in the west.The recovery force is aggregated along coastal areas,and the renewal force tends to aggregate along the eastern coastline.4)Factors such as economic scale,industrial structure,urbanization rate,government fiscal expenditure,and technological talents significantly promote the enhancement of digital trade resilience.This study reveals the dynamic characteristics and influencing factors of digital trade resilience in responding to external shocks,providing theoretical basis and policy suggestions for enhancing digital trade resilience,and promoting high-quality economic development in China.展开更多
A custom micro-arc oxidation(MAO)apparatus is employed to produce coatings under optimized constant voltage–current two-step power supply mode.Various analytical techniques,including scanning electron microscopy,conf...A custom micro-arc oxidation(MAO)apparatus is employed to produce coatings under optimized constant voltage–current two-step power supply mode.Various analytical techniques,including scanning electron microscopy,confocal laser microscopy,X-ray diffraction,X-ray photoelectron spectroscopy,transmission electron microscopy,and electrochemical analysis,are employed to characterize MAO coatings at different stages of preparation.MAO has MgO,hydroxyapatite,Ca_(3)(PO_(4))_(2),and Mg2SiO4 phases.Its microstructure of the coating is characterized by"multiple breakdowns,pores within pores",and"repaired blind pores".The porosity and the uniformity of MAO coating first declines in the constant voltage mode,then augments while the discharge phenomenon takes place,and finally decreases in the repair stage.These analyses reveal a four-stage growth pattern for MAO coatings:anodic oxidation stage,micro-arc oxidation stage,breakdown stage,and repairing stage.During anodic oxidation and MAO stages,inward growth prevails,while the breakdown stage sees outward and accelerated growth.Simultaneous inward and outward growth in the repair stage results in a denser,more uniform coating with increased thickness and improved corrosion resistance.展开更多
The isolated fracture-vug systems controlled by small-scale strike-slip faults within ultra-deep carbonate rocks of the Tarim Basin exhibit significant exploration potential.The study employs a novel training set inco...The isolated fracture-vug systems controlled by small-scale strike-slip faults within ultra-deep carbonate rocks of the Tarim Basin exhibit significant exploration potential.The study employs a novel training set incorporating innovative fault labels to train a U-Net-structured CNN model,enabling effective identification of small-scale strike-slip faults through seismic data interpretation.Based on the CNN faults,we analyze the distribution patterns of small-scale strike-slip faults.The small-scale strike-slip faults can be categorized into NNW-trending and NE-trending groups with strike lengths ranging 200–5000 m.The development intensity of small-scale strike-slip faults in the Lower Yingshan Member notably exceeds that in the Upper Member.The Lower and Upper Yingshan members are two distinct mechanical layers with contrasting brittleness characteristics,separated by a low-brittleness layer.The superior brittleness of the Lower Yingshan Member enhances the development intensity of small-scale strike-slip faults compared to the upper member,while the low-brittleness layer exerts restrictive effects on vertical fault propagation.Fracture-vug systems formed by interactions of two or more small-scale strike-slip faults demonstrate larger sizes than those controlled by individual faults.All fracture-vug system sizes show positive correlations with the vertical extents of associated small-scale strike-slip faults,particularly intersection and approaching fracture-vug systems exhibit accelerated size increases proportional to the vertical extents.展开更多
Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guang...Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guangdong and Guangxi sections of the Pearl River Basin as examples,the transfer-matrix method and standard deviation ellipse model were applied to characterize the evolution of territorial space patterns from 1990 to 2020.A trend surface analysis and the Theil index were used to analyze regional differences in the evolution process,and geodetectors were used to identify the underlying mechanisms of the changes.There were three key results.(1)In these critical areas of the Pearl River Basin,agricultural and ecological spaces have rapidly declined due to urban expansion,with transfers between these spaces dominating the evolution of territorial space patterns.Spatial pattern changes in the Guangdong section were more intense than in the Guangxi section.(2)Regional differences in urban space have decreased,whereas differences in agricultural and ecological spaces have intensified.Driven by socio-economic growth,the cross-regional transfers of territorial space have created a“high in the east,while low in the west”inter-regional difference,and a“high in the south,while low in the north”intra-regional difference shaped by natural conditions.The regional differences in space patterns were greater in Guangdong than in Guangxi.(3)The evolution of watershed territorial space patterns resulted from scale changes,locational shifts,structural reorganizations,and directional changes driven by multiple factors.Natural environment,social life,economic development,and policy factors played foundational,leading,key driving,and guiding roles,respectively.Additionally,the regional differences in the evolution of watershed territorial space patterns originated from the differential transmission of the influence of various factors affecting spatial evolution.Enhancing urban space efficiency,restructuring agricultural space,and optimizing ecological space are key strategies for building a complementary and synergistic territorial space pattern in the basin.展开更多
基金supported by the Scientific and Technological Support Project of Jiangsu Province (No.BS2007084)Seismic Technology Spark Project (No.XH12020)
文摘This thesis discusses the earthquake reflecting ability of the observation well pattern system of Jiangsu Province, China, which has been digitally renovated, and probes into the cause of the major differences in the earthquake reflecting abilities of well holes at different measurement points. This is achieved through the analysis of the co-seismic responses to the Wenchuan (2008; Ms8.0, China) and Tohoku (2011; Ms9.0, Japan) earthquakes. We found that the co-seismic response of water level from regional well holes in Jiangsu Province was stronger than that of water temperature. The water-level co-seismic response follows a consistent law and is closely related to the earthquake magnitude. The co-seismic response of water temperature strongly varied among well points, and was more often manifested as a slow restorative change. The co-seismic responses also varied based on tectonic elements. The response in central and northern Jiangsu was weaker than that of southern Jiangsu, possibly due to the thicker loess cover layer in central Jiangsu which makes it less effective at capturing the micro-changes of stress-strain states relative to the hilly land in the south. The more complicated geological structure in southern Jiangsu makes it contribute to greater changes in the state of underground water after a minor disturbance.
基金supported by the National Natural Science Foundation of China(52106284,52422609)the Natural Science Foundation of Hebei Province(B2021507001)Key Research Special Project of CPPU(ZDZX202501)。
文摘As lithium-ion batteries(LIBs)continue to evolve toward lower costs and higher energy densities,their potential safety risks have become increasingly apparent.Incidents such as explosions at energy storage facilities,fires in electric vehicles,and building fires ignited by charging two-wheeled vehicles have been occurring with alarming frequency,often resulting in significant casualties and injuries.Conducting indepth investigations into thermal runaway(TR)incidents in LIBs can significantly reduce the risk of future occurrences.However,current investigations into LIB fire and explosion incidents face challenges due to the difficulty of conducting in-depth analyses and the lack of a robust theoretical framework to guide these investigations.To enhance the effectiveness of in-depth investigations into battery fire and explosion incidents and to address the lack of theoretical guidance,this paper is the first to systematically examine the conservation and flow patterns of elements during the TR process of LIBs.The analysis reveals that during TR,the gas products generated include approximately 1.5 g of H_(2),23.6 g of CO,88.4 g of CO_(2),8.9 g of C_(2)H_(4),7.3 g of CH_(4),3.7 g of C_(2)H_(6),and 82 g of electrolyte vapor.After TR,the solid compounds formed consist of approximately 2.5 g of LiF,29–92.2 g of elemental Ni/Co/Mn,11.4 g of Li_(2)CO_(3),200.6 g of graphite,1.4 g of NiO,29.6 g of MnO,30.1 g of CoO,67 g of elemental Cu,0.03 g of LiNiO_(2),and 4.3 g of LiAlO_(2).Importantly,the energy released from reactions forming solid compounds during TR surpasses that from gas-forming reactions.This investigation represents the first application of Hess’s law to verify the conservation of elements during the TR process of lithium-ion batteries.The proposed methodology is also applicable to other types of energy storage batteries,effectively advancing techniques for comprehensively investigating lithium battery fire and explosion incidents.
基金Supported by Takeda Pharmaceuticals USA,Inc.Medical writing support was provided by Luke Humphreys,PhD,of Oxford PharmaGenesis,Oxford,UK and was funded by Takeda Development Center Americas,Inc.
文摘BACKGROUND Data regarding complex Crohn’s perianal fistulas(CPF)epidemiology are limited,and optimal treatment strategies are elusive.An improved understanding of how CPF treatment options are used in the real-world setting and factors associated with CPF development,treatment failure,and reasons for undergoing multiple surgeries may help to inform optimal patient management strategies,reduce treatment burden,and improve outcomes in patients with CPF.AIM To describe the epidemiology,treatments,outcomes,and associated risk/protective factors for complex CPF.METHODS Electronic databases(MEDLINE,EMBASE,EBM Reviews,EconLit)were searched.Two reviewers independently used populations,interventions,comparators,outcomes,study designs,and time criteria to identify relevant studies.Observational studies published in English from January 1,2015 to February 17,2022 with>50 patients were included,even if complex CPF was not defined.Items of interest included complex CPF definitions,epidemiology,treatment patterns,morbidity,mortality,and risk factors associated with complex CPF development,treatment failure,and undergoing multiple surgeries.Data were reported using descriptive statistics.RESULTS Overall,140 studies were included.Complex CPF definitions were heterogeneous and rarely reported(24 studies).Hence,data mostly related to CPF in general.CPF prevalence was variable(range:1.5%-81.0%).Incidence was wide-ranging and mostly reported cumulatively at 1-year post-Crohn’s disease diagnosis(range:3.5%-50.1%).Overall healing and failure rates after treatment were in the range of 10.5%-80.2%and 3.6%-83.0%,respectively.Abscesses were the most frequently reported morbidity(n=18).No CPF-related deaths were reported.No consistent risk or protective factors were identified.CONCLUSION Epidemiology,treatment patterns,and risk factors for CPF vary,likely due to inconsistent CPF and clinical outcome definitions.Standardization would facilitate comparability,which may inform optimal complex CPF treatment strategies.
基金supported by the National Key Research and Development Program of China"Key technologies for system stability and HVDC transmission of large-scale renewable energy generation base without conventional power support(2022YFB2402700)"the project of the State Grid Corporation of China(52272222001J).
文摘In wind and solar renewable-dominant hybrid alternating current/direct current(AC/DC)power systems,the active power of high-voltage direct current(HVDC)system is significantly limited by the security and stability events caused by cascading failures.To identify critical lines in cascading failures,a rapid risk assessment method is proposed based on the gradient boosting decision tree(GBDT)and frequent pat-tern growth(FP-Growth)algorithms.First,security and stability events triggered by cascading failures are analyzed to explain the impact of cascading failures on the maximum DC power.Then,a cascading failure risk index is defined,focusing on the DC power being limited.To handle the strong nonlinear relationship between the maximum DC power and cascading failures,a GBDT with an update strategy is utilized to rapidly predict the maximum DC power under uncertain operating conditions.Finally,the FP-Growth algorithm is improved to mine frequent patterns in cascading failures.The importance index for each fault in a frequent pattern is defined by evaluating its impact on cascading failures,enabling the identification of critical lines.Simulation results of a modified Ningxia–Shandong hybrid AC/DC system in China demonstrate that the proposed method can rapidly assess the risk of cascading failures and effectively identify critical lines.
基金supported by the National Natural Science Foundation of China(62001227)the Academy of Finland(315858341489).
文摘This paper considers the short-range sensing imple-mentation in continuous-wave(CW)phased array systems.We specifically address this CW short-range sensing challenges stemming from the self-interference cancellation(SIC)operation and synthesis requirement of arbitrary beampatterns for the sensing purpose,which has rarely been researched before.In this paper,unlike the only existed work that exploits the heuris-tic method and shares no analytical solution,an SIC pattern syn-thesis design is presented with a closed-form solution.By utiliz-ing the null-space projection(NSP)method,the proposed method effectively mitigates the self-interference to enable the in-band full-duplex operation of the array system.Subsequently,the NSP design will be innovatively embedded in a singular value decomposition(SVD)based weighted alternating reserve projec-tion(WARP)approach to efficiently synthesize an arbitrary desired pattern by solving a unique rank-deficient weighted least mean square problem.Numerical results validate the effective-ness of the proposed method in terms of beampattern,SIC per-formance,and sensing performance.
基金supported by the grant from National Natural Science Foundation of China(grant No.81602236).
文摘Erectile dysfunction(ED)is prevalent among men,but its relationship with dietary habits is uncertain.The aim of our study was to assess whether dietary patterns enhance erectile function by reviewing the literature published before August 1,2022,via PubMed,Web of Science,and EMBASE databases.The data compiled included author details;publication dates,countries,treatments,patient numbers,ages,follow-ups,and clinical trial outcomes,such as ED cases,odds ratios(ORs),confidence intervals(CIs),and International Index of Erectile Function-5(IIEF-5)scores with means and standard deviations.An analysis of 14 studies with 27389 participants revealed that plant-based diets(OR=0.71,95%CI:0.66-0.75;P<0.00001),low-fat diets(OR=0.27,95%CI:0.13-0.53;P=0.0002),and alternative diets such as intermittent fasting and organic diets(OR=0.54,95%CI:0.36-0.80;P=0.002)significantly reduced ED risk.High-protein low-fat diets(hazard ratio[HR]=1.38,95%CI:1.12-1.64;P<0.00001)and high-carb low-fat diets(HR=0.79,95%CI:0.55-1.04;P<0.00001)improved IIEF-5 scores.Combined diet and exercise interventions decreased the likelihood of ED(OR=0.49,95%CI:0.28-0.85;P=0.01)and increased the IIEF-5 score(OR=3.40,95%CI:1.69-5.11;P<0.0001).Diets abundant in fruits and vegetables(OR=0.97,95%CI:0.96-0.98;P<0.00001)and nuts(OR=0.54,95%CI:0.37-0.80;P=0.002)were also correlated with lower ED risk.Our meta-analysis underscores a strong dietary-ED association,suggesting that low-fat/Mediterranean diets rich in produce and nuts could benefit ED management.
基金financially supported by the National Natural Science Foundation of China (Grant No. 41461011)。
文摘The Yellow River Delta(YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the region has witnessed significant land use/cover changes(LUCC), impacting ecosystem services(ES) and ecological security patterns(ESP). Investigating LUCC's effects on ES and ESP in the YRD is crucial for ecological security and sustainable development. This study utilized the PLUS model to simulate 2030 land use scenarios, including natural development(NDS), economic development(EDS), and ecological protection scenarios(EPS). Subsequently, the InVEST model and circuit theory were applied to assess ES and ESP under varying LUCC scenarios from 2010 to 2030. Findings indicate:(1) Notable LUCC from 2010 to 2030, marked by decreasing cropland and increasing construction land and water bodies.(2) From 2010 to 2020, improvements were observed in carbon storage,water yield, soil retention, and habitat quality, whereas 2020–2030 saw increases in water yield and soil retention but declines in habitat quality and carbon storage. Among the scenarios, EPS showed superior performance in all four ES.(3) Between 2010 and 2030, ecological sources, corridors, and pinchpoints expanded, displaying significant spatial heterogeneity. The EPS scenario yielded the most substantial increases in ecological sources,corridors, and pinchpoints, totaling 582.89 km^(2), 645.03 km^(2),and 64.43 km^(2), respectively. This study highlights the importance of EPS, offering insightful scientific guidance for the YRD's sustainable development.
文摘The objectives of this study were to assess distribution patterns of plant species richness,plant diversity and vegetation structure in relation to environmental factors along elevation gradient in Al-Jabal Al-Akhdar,Libya.For each species,its growth form,chorological affinities,degree of occurrence,endemism status and originality were provided.A total of 534 taxa were generated from 70 families of the flowering plants,and 3 of the non-flowering plants were identified.The native flora of the study area was counted for 80.2%of the total indigenous taxa(465).The hump-shaped pattern of plant species richness was obtained,with the highest species richness at the mid-elevations,and both ends of the gradient have the lowest.The annuals(300 species,56.2%)and non-succulent perennial herbs(165 species,30.9%)were the most dominant growth forms of the total species composition.Along the elevation gradient,Asteraceae,Fabaceae,Poaceae,Lamiaceae and Apiaceae were the dominant families with the highest numbers of species.This investigation recorded 31 endemic taxa,comprising 25 dicots and 6 monocots,primarily of Mediterranean origin,with most belonging to the Asteraceae and Lamiaceae families.Mediterranean chorotype was the dominant,whether pure(mono-),or combined with one(bi-and pluri-regional)or more(pluri-regional).Application of cluster analysis on the vegetation data yielded four cluster groups;each was linked to an elevation level.It emphasized the importance of establishing conservation strategies to minimize human disturbance and safeguard relic habitats of Juniperus phoenicea L.at its southern distribution limits in Africa,underlining the proactive management required for species preservation.The application of Redundancy Analysis revealed that Shannon diversity index(H'),pH and Fe were the determinant soil factor in the mid-elevation levels(L2 and L3)whereas altitude,fine sand,HCO3,OM,and soil contents of Na,SO4 and Cl for the extreme levels(L1 and L4).
基金carried out in the framework of the 1331 Project of Cultural Ecology Collaborative Innovation Center in Wutai Mountain (00000342)co-financed by Program for the Philosophy and Social Sciences Research of Higher Learning Institutions of Shanxi (2022J027)+1 种基金Applied Basic Research Project of Shanxi Province (202203021221225)Basic Research Project of Xinzhou Science and Technology Bureau (20230501)。
文摘Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradients in subalpine meadow ecosystems. To reveal the elevational patterns of warming effects on plant biodiversity, community structure, productivity, and soil properties, we conducted a warming experiment using open-top chambers from August 2019 to August 2022 at high(2764 m a. s. l.), medium(2631 m a. s. l.), and low(2544 m a. s. l.) elevational gradients on a subalpine meadow slope of Mount Wutai, Northern China. Our results showed that three years of warming significantly increased topsoil temperature but significantly decreased topsoil moisture at all elevations(P<0.05), and the percentage of increasing temperature and decreasing moisture both gradually raised with elevation lifting. Warming-induced decreasing proportions of soil organic carbon(SOC, by 19.24%), and total nitrogen(TN, by 24.56%) were the greatest at high elevational gradients. Experimental warming did not affect topsoil C: N, p H, NO_(3)^(-)-N, or NH_(4)^(+)-N at the three elevational gradients. Warming significantly increased species richness(P<0.01) and Shannon-Weiner index(P<0.05) at low elevational gradients but significantly decreased belowground biomass(P<0.05) at a depth of 0–10 cm at three elevational gradients. Warming caused significant increases in the aboveground biomass in the three elevational plots. Warming significantly increased the aboveground biomass of graminoids in medium(by 92.47%) and low(by 98.25%) elevational gradients, that of sedges in high(by 72.44%) and medium(by 57.16%) elevational plots, and that of forbs in high(by 75.88%), medium(by 34.38%), and low(by 74.95%) elevational plots. Species richness had significant linear correlations with SOC, TN, and C: N(P<0.05), but significant nonlinear responses to soil temperature and soil moisture in the warmed treatment(P<0.05). The warmed aboveground biomass had a significant nonlinear response to soil temperature and significant linear responses to soil moisture(P<0.05). This study provided evidence that altitude is a factor in sensitivity to climate warming, and these different parameters(e.g., plant species richness, Shannon-Weiner index, soil temperature, soil moisture, SOC, and TN) can be used to measure this sensitivity.
文摘A prediction framework based on the evolution of pattern motion probability density is proposed for the output prediction and estimation problem of non-Newtonian mechanical systems,assuming that the system satisfies the generalized Lipschitz condition.As a complex nonlinear system primarily governed by statistical laws rather than Newtonian mechanics,the output of non-Newtonian mechanics systems is difficult to describe through deterministic variables such as state variables,which poses difficulties in predicting and estimating the system’s output.In this article,the temporal variation of the system is described by constructing pattern category variables,which are non-deterministic variables.Since pattern category variables have statistical attributes but not operational attributes,operational attributes are assigned to them by posterior probability density,and a method for analyzing their motion laws using probability density evolution is proposed.Furthermore,a data-driven form of pattern motion probabilistic density evolution prediction method is designed by combining pseudo partial derivative(PPD),achieving prediction of the probability density satisfying the system’s output uncertainty.Based on this,the final prediction estimation of the system’s output value is realized by minimum variance unbiased estimation.Finally,a corresponding PPD estimation algorithm is designed using an extended state observer(ESO)to estimate the parameters to be estimated in the proposed prediction method.The effectiveness of the parameter estimation algorithm and prediction method is demonstrated through theoretical analysis,and the accuracy of the algorithm is verified by two numerical simulation examples.
文摘AIM:To determine the smartphone use patterns and effects of smartphone use on accommodation and convergence system of the eyes among Malaysian teenagers.METHODS:A total of 62 participants aged between 13 and 17y were involved.A self-administered questionnaires containing 12 items was used to evaluate the smartphone usage patterns.This was followed by an eye examination,involving a battery of accommodation and convergence assessments before and after the smartphone use.The data analysis comprised descriptive statistics,paired t-test,and correlation coefficients.RESULTS:The use of smartphones is at a high level and at an optimal distance daily,with more than 6h a day watching video films,games,and completing school projects.Majority of the participants not reported eye strain factors and eye prescription changes with the use of digital devices.The use of a smartphone continuously for 30min was found to significantly decrease amplitude of accommodation,accommodative facility,and positive relative accommodation(P<0.001).Meanwhile,the lag of accommodation parameters and negative relative accommodation increased with the use of smartphones significantly(P<0.001).The near point of convergence(NPC)and distance and near negative fusional vergence decreased significantly(P<0.001).The NPC parameter was found to have a weak negative association with the frequency of smartphone use(R=-0.276,P<0.05).CONCLUSION:Frequent and continuous use of smartphones have increased visual stress and resulted in weakness of accommodation and vergence functions.Therefore,frequent break is mandatory when using a smartphone and appropriate visual hygiene,the 20-20-20 rule(every 20min,view something 20 feet away for 20s)are required during smartphone use to maintain visual function.
基金supported by the Guangdong Basic and Applied Basic Research project (No.2020B0301030004)the Key-Area Research and Development Program of Guangdong Province (No.2020B1111360003)+1 种基金the National Natural Science Foundation of China (No.42105103)the Guangdong Basic and Applied Basic Research Foundation (No.2022A1515011554).
文摘Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns(SWPs),however,the consistency of different classification methods is rarely examined.In this study,we apply two widely-used objective methods,the self-organizing map(SOM)and K-means clustering analysis,to derive ozone-favorable SWPs at four Chinese megacities in 2015-2022.We find that the two algorithms are largely consistent in recognizing dominant ozone-favorable SWPs for four Chinese megacities.In the case of classifying six SWPs,the derived circulation fields are highly similar with a spatial correlation of 0.99 between the two methods,and the difference in themean frequency of each SWP is less than 7%.The six dominant ozone-favorable SWPs in Guangzhou are all characterized by anomaly higher radiation and temperature,lower cloud cover,relative humidity,and wind speed,and stronger subsidence compared to climatology mean.We find that during 2015-2022,the occurrence of ozone-favorable SWPs days increases significantly at a rate of 3.2 days/year,faster than the increases in the ozone exceedance days(3.0 days/year).The interannual variability between the occurrence of ozone-favorable SWPs and ozone exceedance days are generally consistent with a temporal correlation coefficient of 0.6.In particular,the significant increase in ozone-favorable SWPs in 2022,especially the Subtropical High type which typically occurs in September,is consistent with a long-lasting ozone pollution episode in Guangzhou during September 2022.Our results thus reveal that enhanced frequency of ozone-favorable SWPs plays an important role in the observed 2015-2022 ozone increase in Guangzhou.
基金supported by the National Natural Science Foundation of China(62374142,12175189 and 11904302)External Cooperation Program of Fujian(2022I0004)+1 种基金Fundamental Research Funds for the Central Universities(20720190005 and 20720220085)Major Science and Technology Project of Xiamen in China(3502Z20191015).
文摘The preparation of red,green,and blue quantum dot(QD)pixelated arrays with high precision,resolution,and brightness poses a significant challenge on the development of advanced micro-displays for virtual,augmented,and mixed reality applications.Alongside the controlled synthesis of high-performance QDs,a reliable QD patterning technology is crucial in overcoming this challenge.Among the various methods available,photolithography-based patterning technologies show great potentials in producing ultra-fine QD patterns at micron scale.This review article presents the recent advancements in the field of QD patterning using photolithography techniques and explores their applications in micro-display technology.Firstly,we discuss QD patterning through photolithography techniques employing photoresist(PR),which falls into two categories:PRassisted photolithography and photolithography of QDPR.Subsequently,direct photolithography techniques based on photo-induced crosslinking of photosensitive groups and photo-induced ligand cleavage mechanisms are thoroughly reviewed.Meanwhile,we assess the performance of QD arrays fabricated using these photolithography techniques and their integration into QD light emitting diode display devices as well as color conversionbased micro light emitting diode display devices.Lastly,we summarize the most recent developments in this field and outline future prospects.
基金funded by the Yunnan Provincial Basic Research Joint Special Fund Project(2019FH001(-052))Cangshan Mountain Synthetic Scientific Expeditions Fund.
文摘The Hengduan Mountains,situated on the southeastern edge of the Qinghai-Tibet Plateau,are the longest and widest north-south-oriented mountain range in China,exerting a significant influence on the ecological and geographical pattern.Understanding the topographic and geomorphological characteristics of the Hengduan Mountains is fundamental and crucial for research in related fields such as ecology,geography,and sustainability.In this study,Digital Elevation Model(DEM)data were utilized to extract and analyze the topography and geomorphology(TG)pattern.TG maps have been developed to quantitatively classify the TG types in the Hengduan Mountains by combining the five factors of elevation,slope,aspect,relief and landform.The spatial distribution and quantitative characteristics of these factors were mapped and investigated using geographic information systems.The results revealed that:(1)The Hengduan Mountains exhibit an elongated north-south distribution,with an average elevation of approximately 3746 m,an average slope of around 25°,and an average relief of about 266 m.(2)The Hengduan Mountains display significant elevation differences,with an overall high elevation,characterized by a trend of lower elevation in the east and higher elevation in the west,as well as irregular orientations of various aspects.(3)The 19 landform types were identified,the landform types of the Hengduan Mountains are primarily composed of low-relief high-mountains(42.0618%),low-relief mid-mountains(22.4624%),and high-elevation hills(20.5839%).The results of the study can provide data and information support for the ecology,environmental protection and sustainable development of the Hengduan Mountains.
基金supported by the International Collaborative Research Program(fundamental research,2021-2023)funded by Korea Institute of Civil Engineering and Building Technology(KICT).
文摘Rock fractures or faults could be reactivated by the thermal stress generated during the decay process of the high-level radioactive waste in deep geological repositories(DGRs).Understanding thermoshearing behavior and its influencing factors are important for the long-term performance assessment of DGRs.We designed multistage mechanical(M)shear tests and thermomechanical(TM)shear tests on three 100 mm-cubic granite specimens,each containing a single inclined sawcut fracture with distinct microroughness of 8-15μm.M test results have shown that the static friction coefficient of the granite fracture decreases in proportion to the increase in the logarithm of the loading rate within the range of 1-15 kPa/s.For the given heating and boundary conditions,thermal loading rate,i.e.,thermal stress increment with heating time,is measured to be around 1 kPa/s in the fractured granite.Thermoshearing can be well predicted by the linear Mohr-Coulomb failure envelope deduced from M shear tests employing a loading rate that is comparable with the thermal loading rate.The granite fractures exhibited two distinct slip patterns during the mechanical shearing,i.e.,stick-slip observed in the smooth fracture and stable sliding in the relatively rough surface.In contrast,the mechanical loading rate(1-15 kPa/s)investigated in this study appears to not influence the slip pattern.Unlike those in M shear tests,thermoshearing in both smooth and relatively rough fractures show stable sliding with a very slow peak velocity of around 0.002μm/s.
基金Under the auspices of National Natural Science Foundation of China(No.42471205)the General Scientific Research Project of Zhejiang Provincial Department of Education(No.2024JYTYB12)the Philosophy and Social Science Planning Project of Zhejiang Province(No.23NDJC109YB)。
文摘In the era of the digital economy,digital trade has demonstrated strong vitality,becoming a crucial driving force for the highquality development of national and regional economies.However,understanding the resilience of digital trade in the face of external crises is an important topic.Taking the backdrop of Sino-US trade friction,this paper constructs a resilience index system for digital trade.It utilizes entropy method,kernel density estimation,and ArcGIS mapping to calculate and visually analyze the resilience of China’s digital trade from 2017 to 2021.Additionally,a Tobit model is constructed to explore the main influencing factors of digital trade resilience patterns.The research findings indicate:1)temporally,during the period of Sino-US trade friction,China’s digital trade resilience shows an overall upward trend,but there are regional differences in resilience levels across the country,with a severe polarization phenomenon.2)Spatially,high resilience is observed in the eastern and central regions of China,while the western and northeastern regions exhibit low resilience.3)From a dimensional perspective,the resistance of digital trade resilience displays a spatial distribution of high values in the east and low values in the west.The recovery force is aggregated along coastal areas,and the renewal force tends to aggregate along the eastern coastline.4)Factors such as economic scale,industrial structure,urbanization rate,government fiscal expenditure,and technological talents significantly promote the enhancement of digital trade resilience.This study reveals the dynamic characteristics and influencing factors of digital trade resilience in responding to external shocks,providing theoretical basis and policy suggestions for enhancing digital trade resilience,and promoting high-quality economic development in China.
文摘A custom micro-arc oxidation(MAO)apparatus is employed to produce coatings under optimized constant voltage–current two-step power supply mode.Various analytical techniques,including scanning electron microscopy,confocal laser microscopy,X-ray diffraction,X-ray photoelectron spectroscopy,transmission electron microscopy,and electrochemical analysis,are employed to characterize MAO coatings at different stages of preparation.MAO has MgO,hydroxyapatite,Ca_(3)(PO_(4))_(2),and Mg2SiO4 phases.Its microstructure of the coating is characterized by"multiple breakdowns,pores within pores",and"repaired blind pores".The porosity and the uniformity of MAO coating first declines in the constant voltage mode,then augments while the discharge phenomenon takes place,and finally decreases in the repair stage.These analyses reveal a four-stage growth pattern for MAO coatings:anodic oxidation stage,micro-arc oxidation stage,breakdown stage,and repairing stage.During anodic oxidation and MAO stages,inward growth prevails,while the breakdown stage sees outward and accelerated growth.Simultaneous inward and outward growth in the repair stage results in a denser,more uniform coating with increased thickness and improved corrosion resistance.
基金supported by the National Natural Science Foundation of China(No.U21B2062).
文摘The isolated fracture-vug systems controlled by small-scale strike-slip faults within ultra-deep carbonate rocks of the Tarim Basin exhibit significant exploration potential.The study employs a novel training set incorporating innovative fault labels to train a U-Net-structured CNN model,enabling effective identification of small-scale strike-slip faults through seismic data interpretation.Based on the CNN faults,we analyze the distribution patterns of small-scale strike-slip faults.The small-scale strike-slip faults can be categorized into NNW-trending and NE-trending groups with strike lengths ranging 200–5000 m.The development intensity of small-scale strike-slip faults in the Lower Yingshan Member notably exceeds that in the Upper Member.The Lower and Upper Yingshan members are two distinct mechanical layers with contrasting brittleness characteristics,separated by a low-brittleness layer.The superior brittleness of the Lower Yingshan Member enhances the development intensity of small-scale strike-slip faults compared to the upper member,while the low-brittleness layer exerts restrictive effects on vertical fault propagation.Fracture-vug systems formed by interactions of two or more small-scale strike-slip faults demonstrate larger sizes than those controlled by individual faults.All fracture-vug system sizes show positive correlations with the vertical extents of associated small-scale strike-slip faults,particularly intersection and approaching fracture-vug systems exhibit accelerated size increases proportional to the vertical extents.
基金National Social Science Foundation Program,No.22VRC163National Natural Science Foundation of China,No.42061043+1 种基金Postgraduate Research&Practice Innovation Program of Jiangsu Province,No.KYCX24_1008Innovation Project of Guangxi Graduate Education,No.YCSW2024473。
文摘Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guangdong and Guangxi sections of the Pearl River Basin as examples,the transfer-matrix method and standard deviation ellipse model were applied to characterize the evolution of territorial space patterns from 1990 to 2020.A trend surface analysis and the Theil index were used to analyze regional differences in the evolution process,and geodetectors were used to identify the underlying mechanisms of the changes.There were three key results.(1)In these critical areas of the Pearl River Basin,agricultural and ecological spaces have rapidly declined due to urban expansion,with transfers between these spaces dominating the evolution of territorial space patterns.Spatial pattern changes in the Guangdong section were more intense than in the Guangxi section.(2)Regional differences in urban space have decreased,whereas differences in agricultural and ecological spaces have intensified.Driven by socio-economic growth,the cross-regional transfers of territorial space have created a“high in the east,while low in the west”inter-regional difference,and a“high in the south,while low in the north”intra-regional difference shaped by natural conditions.The regional differences in space patterns were greater in Guangdong than in Guangxi.(3)The evolution of watershed territorial space patterns resulted from scale changes,locational shifts,structural reorganizations,and directional changes driven by multiple factors.Natural environment,social life,economic development,and policy factors played foundational,leading,key driving,and guiding roles,respectively.Additionally,the regional differences in the evolution of watershed territorial space patterns originated from the differential transmission of the influence of various factors affecting spatial evolution.Enhancing urban space efficiency,restructuring agricultural space,and optimizing ecological space are key strategies for building a complementary and synergistic territorial space pattern in the basin.