期刊文献+
共找到18,300篇文章
< 1 2 250 >
每页显示 20 50 100
The first discovery of non-avian dinosaur egg and bone fossils in the Hefei Basin 被引量:1
1
作者 WANG Qiang DONG Zhe +4 位作者 MAO Lei ZHU Xu-Feng CHEN Yan-Bin HUANG Jian-Dong DING Hai-Dong 《古脊椎动物学报(中英文)》 北大核心 2025年第3期248-252,共5页
This report is about the first record of non-avian dinosaur eggs in the Hefei Basin,Anhui Province,China.Based on the combination of elongated egg body,linear ridges on the outer surface and two structure layer,the eg... This report is about the first record of non-avian dinosaur eggs in the Hefei Basin,Anhui Province,China.Based on the combination of elongated egg body,linear ridges on the outer surface and two structure layer,the eggs can be referred to Elongatoolithidae.The gradual boundary between the cone and the column layers as well as the relative thin eggshell(less than 1 mm)indicates its affinity within Elongatoolithus.The eggs are identified as Elongatoolithus oosp.,as they were severely compressed and experienced erosion on both inner and outer surfaces.The discovery of egg fossil in the Hefei Basin offers evidence for stratum comparison in this region and supplements the diversity of egg fossils in Anhui.Meanwhile,this discovery also enriches the paleogeographic distribution of elongatoolithids. 展开更多
关键词 Hefei Basin Upper Cretaceous Zhangqiao Formation egg fossil Elongatoolithidae
在线阅读 下载PDF
Impacts of synoptic weather patterns on Hefei's ozone in warm season and analysis of transport pathways during extreme pollution events 被引量:1
2
作者 Feng Hu Pinhua Xie +5 位作者 Jin Xu Ang Li Yinsheng Lv Zhidong Zhang Jiangyi Zheng Xin Tian 《Journal of Environmental Sciences》 2025年第10期371-384,共14页
Extreme ozone pollution events(EOPEs)are associated with synoptic weather patterns(SWPs)and pose severe health and ecological risks.However,a systematic investigation of themeteorological causes,transport pathways,and... Extreme ozone pollution events(EOPEs)are associated with synoptic weather patterns(SWPs)and pose severe health and ecological risks.However,a systematic investigation of themeteorological causes,transport pathways,and source contributions to historical EOPEs is still lacking.In this paper,the K-means clustering method is applied to identify six dominant SWPs during the warm season in the Yangtze River Delta(YRD)region from 2016 to 2022.It provides an integrated analysis of the meteorological factors affecting ozone pollution in Hefei under different SWPs.Using the WRF-FLEXPART model,the transport pathways(TPPs)and geographical sources of the near-surface air masses in Hefei during EOPEs are investigated.The results reveal that Hefei experienced the highest ozone concentration(134.77±42.82μg/m^(3)),exceedance frequency(46 days(23.23%)),and proportion of EOPEs(21 instances,47.7%)under the control of peripheral subsidence of typhoon(Type 5).Regional southeast winds correlated with the ozone pollution in Hefei.During EOPEs,a high boundary layer height,solar radiation,and temperature;lowhumidity and cloud cover;and pronounced subsidence airflow occurred over Hefei and the broader YRD region.The East-South(E_S)patterns exhibited the highest frequency(28 instances,65.11%).Regarding the TPPs and geographical sources of the near-surface air masses during historical EOPEs.The YRD was the main source for land-originating air masses under E_S patterns(50.28%),with Hefei,southern Anhui,southern Jiangsu,and northern Zhejiang being key contributors.These findings can help improve ozone pollution early warning and control mechanisms at urban and regional scales. 展开更多
关键词 OZONE Objective weather classification Transport pathway Source attribution Hefei
原文传递
Upper crustal azimuthal anisotropy and seismogenic tectonics of the Hefei segment of the Tan-Lu Fault Zone from ambient noise tomography 被引量:1
3
作者 Cheng Li HuaJianYao +4 位作者 Song Luo HaiJiang Zhang LingLi Li XiaoLi Wang ShengJun Ni 《Earth and Planetary Physics》 2025年第2期253-265,共13页
The Tan-Lu Fault Zone is a large NNE-trending fault zone that has a substantial effect on the development of eastern China and its earthquake disaster prevention efforts. Aiming at the azimuthally anisotropic structur... The Tan-Lu Fault Zone is a large NNE-trending fault zone that has a substantial effect on the development of eastern China and its earthquake disaster prevention efforts. Aiming at the azimuthally anisotropic structure in the upper crust and seismogenic tectonics in the Hefei segment of this fault, we collected phase velocity dispersion data of fundamental mode Rayleigh waves from ambient noise cross-correlation functions of ~400 temporal seismographs in an area of approximately 80 × 70 km along the fault zone. The period band of the dispersion data was ~0.5–10 s. We inverted for the upper crustal three-dimensional(3-D) shear velocity model with azimuthal anisotropy from the surface to 10 km depth by using a 3-D direct azimuthal anisotropy inversion method. The inversion result shows the spatial distribution characteristics of the tectonic units in the upper crust. Additionally, the deformation of the Tan-Lu Fault Zone and its conjugated fault systems could be inferred from the anisotropy model. In particular, the faults that have remained active from the early and middle Pleistocene control the anisotropic characteristics of the upper crustal structure in this area. The direction of fast axes near the fault zone area in the upper crust is consistent with the strike of the faults, whereas for the region far away from the fault zone, the direction of fast axes is consistent with the direction of the regional principal stress caused by plate movement. Combined with the azimuthal anisotropy models in the deep crust and uppermost mantle from the surface wave and Pn wave, the different anisotropic patterns caused by the Tan-Lu Fault Zone and its conjugated fault system nearby are shown in the upper and lower crust. Furthermore,by using the double-difference method, we relocated the Lujiang earthquake series, which contained 32 earthquakes with a depth shallower than 10 km. Both the Vs model and earthquake relocation results indicate that earthquakes mostly occurred in the vicinity of structural boundaries with fractured media, with high-level development of cracks and small-scale faults jammed between more rigid areas. 展开更多
关键词 ambient noise tomography azimuthal anisotropy upper crust seismogenic structure the Tan-Lu Fault Zone Hefei segment
在线阅读 下载PDF
Angular vibration analysis of a plane grating monochromator at the Hefei Advanced Light Facility
4
作者 Xiang Zhong Jixia Yi +6 位作者 Xinyu Lian Huaxia Deng Guanghui Han Mengchao Ma Yang Peng Shen Wei Xinglong Gong 《Theoretical & Applied Mechanics Letters》 2025年第5期421-426,共6页
The stability of the plane grating monochromator in the Hefei Advanced Light Facility is highly important for beamline focusing,with angular vibration being a key indicator for assessing its stability.This paper propo... The stability of the plane grating monochromator in the Hefei Advanced Light Facility is highly important for beamline focusing,with angular vibration being a key indicator for assessing its stability.This paper proposes an elastic fitting method based on fifth-order polynomial fitting for the precise analysis of microangular vibrations on grating surfaces.Compared with the traditional rigid body method,this method fully considers the three major elastic characteristics exhibited by optical components during vibration:significant phase differences,nonuniform deformation gradients,and spatial distribution differences in angular deformation.The research results indicate that this method can accurately reflect the actual vibration state of the grating surface,not only enabling the quantitative prediction of local angular microvibration but also establishing a reliable theoretical analysis framework for the stability assessment of high-precision instruments. 展开更多
关键词 Hefei Advanced Light Facility Dynamic simulations Elastic deformation Local angular microvibration
在线阅读 下载PDF
Discovery of a Novel Ginseng Polysaccharide:Structure Characterization,in vitro Fermentability and Anti-oxidative Mechanism of Fermented Product via the Nrf2/HO-1 Pathway on Aβ-induced-PC 12 Cells
5
作者 DONG Binbin HOU Zong +3 位作者 ZHENG Zhong XING Junpeng LIU Zhiqiang LIU Shu 《高等学校化学学报》 北大核心 2026年第1期173-189,共17页
In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented... In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs. 展开更多
关键词 Ginseng polysaccharide Structural characterization Intestinal microbiota FERMENTABILITY Oxidative stress
在线阅读 下载PDF
Relationship of Non-Essential and Essential Metals with Vitamin D in a Chinese Early Adolescent Cohort
6
作者 Gengfu Wang Weibo Liu +9 位作者 Min Li Ting Tang Qi Zhong Guangbo Qu Yi Zhou Mengyuan Yuan Yonghan Li Fangbiao Tao Puyu Su Chaoxue Zhang 《Biomedical and Environmental Sciences》 2026年第1期116-122,共7页
Vitamin D deficiency(VDD)represents a significant nutritional concern among children and adolescents.The estimated prevalence of VDD in China is 46.8%in this population^([1]).VDD during childhood and adolescence has b... Vitamin D deficiency(VDD)represents a significant nutritional concern among children and adolescents.The estimated prevalence of VDD in China is 46.8%in this population^([1]).VDD during childhood and adolescence has been associated with the onset of various conditions,including acute respiratory infections,asthma,atopic dermatitis,and food allergies^([2]).Multiple factors,including age,sun exposure,adiposity,and genetics,influence vitamin D levels^([2,3]).Increasing attention has been directed toward understanding the environmental determinants that may influence vitamin D status.Given the potential of metallic pollutants to disrupt endocrine function and their ubiquity in the environment,investigating the effects of metal exposure on human vitamin D status,particularly in vulnerable populations,is imperative. 展开更多
关键词 vitamin d deficiency vdd represents Chinese early adolescent cohort essential metals vitamin d non essential metals food allergies multiple acute respiratory infectionsasthmaatopic dermatitisand vitamin D deficiency
暂未订购
Crushing evolution in pebble bed based on a novel method:a crushable DEM study
7
作者 Jian Wang Ming‑Zhun Lei +4 位作者 Ming‑Zong Liu Qi‑Gang Wu Zi‑Cong Cai Kai‑Song Wang Hai‑Shun Deng 《Nuclear Science and Techniques》 2026年第1期212-224,共13页
In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical m... In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical model,and its validity was verified using a simple impact test.A crushable discrete element method(DEM)framework is built based on the previously established theoretical model.The tensile strength,which considers the fractal theory,size effect,and Weibull variation,was assigned to each generated particle.The assigned strength is then used for crush detection by comparing it with its maximum tensile stress.Mass conservation is ensured by inserting a series of sub-particles whose total mass was equal to the quality loss.Based on the crushable DEM framework,a numerical simulation of the crushing behavior of a pebble bed with hollow cylindrical geometry under a uniaxial compression test was performed.The results of this investigation showed that the particle withstands the external load by contact and sliding at the beginning of the compression process,and the results confirmed that crushing can be considered an important method of resisting the increasing external load.A relatively regular particle arrangement aids in resisting the load and reduces the occurrence of particle crushing.However,a limit exists to the promotion of resistance.When the strain increases beyond this limit,the distribution of the crushing position tends to be isotropic over the entire pebble bed.The theoretical model and crushable DEM framework provide a new method for exploring the pebble bed in a fusion reactor,considering particle crushing. 展开更多
关键词 Crushing behavior Granular material Discrete element method Pebble bed Fractal theory
在线阅读 下载PDF
Monolithically Integrated Optical Convolutional Processors on Thin Film Lithium Niobate
8
作者 Rui-Xue Liu Yong Zheng +5 位作者 Yuan Ren Bo-Yang Nan Yun-Peng Song Rong-Bo Wu Min Wang Ya Cheng 《Chinese Physics Letters》 2026年第1期49-63,共15页
Photonic neural networks(PNNs)of sufficiently large physical dimensions and high operation accuracies are envisaged as ideal candidates for breaking the major bottlenecks in the current artificial intelligence archite... Photonic neural networks(PNNs)of sufficiently large physical dimensions and high operation accuracies are envisaged as ideal candidates for breaking the major bottlenecks in the current artificial intelligence architectures in terms of latency,energy efficiency,and computational power.To achieve this vision,it is of vital importance to scale up the PNNs while simultaneously reducing the high demand on the dimensions required by them.The underlying cause of this strategy is the enormous gap between the scales of photonic and electronic integrated circuits.Here,we demonstrate monolithically integrated optical convolutional processors on thin film lithium niobate(TFLN)that harness inherent parallelism in photonics to enable large-scale programmable convolution kernels and,in turn,greatly reduce the dimensions required by subsequent fully connected layers.Experimental validation achieves high classification accuracies of 96%(86%)on the MNIST(Fashion-MNIST)dataset and 84.6%on the AG News dataset while dramatically reducing the required subsequent fully connected layer dimensions to 196×10(from 784×10)and 175×4(from 800×4),respectively.Furthermore,our devices can be driven by commercial field-programmable gate array systems;a unique advantage in addition to their scalable channel number and kernel size.Our architecture provides a solution to build practical machine learning photonic devices. 展开更多
关键词 photonic neural networks pnns artificial intelligence architectures breaking major bottlenecks monolithic integration LATENCY energy efficiency thin film lithium niobate photonic neural networks
原文传递
Between Themis and Prometheus:a history of the ethics of science and technology
9
作者 Jia-Yun Chen Zong-Zhen Wu +7 位作者 Qiang-Yu Xiang Lu Zhang Jia-Lin Diao Ya-Hui Zhang Shen-Shen Yan Kun-Lan Zuo Jian-Liang Huang Huan Liu 《History and Philosophy of Medicine》 2026年第1期49-59,共11页
Background:With the rapid development of modern emerging technologies,the ethical dilemmas and social controversies triggered by scientific and technological activities have become increasingly prominent.How to guide ... Background:With the rapid development of modern emerging technologies,the ethical dilemmas and social controversies triggered by scientific and technological activities have become increasingly prominent.How to guide technology for good and prevent and control technological risks has become an important issue of global concern.Research on science and technology ethics is dedicated to integrating ethical theories into governance practices and constructing ethical models that adapt to the development of the times.Methods:This article systematically reviews the six core approaches of scientific and technological ethics thought,including technological autonomy and political philosophy criticism,responsibility ethics and intergenerational obligations,technological intermediation and the integration of life and the world,ethical principles and normative frameworks,participatory governance and ethical practice innovation,as well as domain-specific ethical norms,thereby constructing an ethical analysis framework applicable to medical technology risks.And cross-analysis was conducted by taking medical events such as gene editing and xenotransplantation as examples.Results:Research shows that a single ethical approach has limitations in addressing complex medical ethical challenges,while the six approaches are complementary and synergistic.By criticizing technological autonomy,establishing a responsibility ethics orientation,setting the bottom line of ethical principles,promoting participatory governance,formulating domain norms,and continuously reflecting on the intermediary nature of technology,a multi-level and dynamically adaptive governance system for scientific and technological ethics can be constructed.Conclusion:The key to addressing contemporary medical ethics challenges lies in the comprehensive application of science and technology ethics theories and the integration of ethical considerations throughout the entire process of scientific and technological research and development.In the future,a governance framework that adapts to the development of new technologies should be established to promote cross-cultural and cross-disciplinary ethical dialogue and public participation,ensuring that scientific and technological innovation always serves the dignity of human life and overall well-being. 展开更多
关键词 ethics of science and technology history of science ethical governance responsible innovation medical ethics
暂未订购
Ultrathin Gallium Nitride Quantum-Disk-in-Nanowire-Enabled Reconfigurable Bioinspired Sensor for High-Accuracy Human Action Recognition
10
作者 Zhixiang Gao Xin Ju +10 位作者 Huabin Yu Wei Chen Xin Liu Yuanmin Luo Yang Kang Dongyang Luo JiKai Yao Wengang Gu Muhammad Hunain Memon Yong Yan Haiding Sun 《Nano-Micro Letters》 2026年第2期439-453,共15页
Human action recognition(HAR)is crucial for the development of efficient computer vision,where bioinspired neuromorphic perception visual systems have emerged as a vital solution to address transmission bottlenecks ac... Human action recognition(HAR)is crucial for the development of efficient computer vision,where bioinspired neuromorphic perception visual systems have emerged as a vital solution to address transmission bottlenecks across sensor-processor interfaces.However,the absence of interactions among versatile biomimicking functionalities within a single device,which was developed for specific vision tasks,restricts the computational capacity,practicality,and scalability of in-sensor vision computing.Here,we propose a bioinspired vision sensor composed of a Ga N/Al N-based ultrathin quantum-disks-in-nanowires(QD-NWs)array to mimic not only Parvo cells for high-contrast vision and Magno cells for dynamic vision in the human retina but also the synergistic activity between the two cells for in-sensor vision computing.By simply tuning the applied bias voltage on each QD-NW-array-based pixel,we achieve two biosimilar photoresponse characteristics with slow and fast reactions to light stimuli that enhance the in-sensor image quality and HAR efficiency,respectively.Strikingly,the interplay and synergistic interaction of the two photoresponse modes within a single device markedly increased the HAR recognition accuracy from 51.4%to 81.4%owing to the integrated artificial vision system.The demonstration of an intelligent vision sensor offers a promising device platform for the development of highly efficient HAR systems and future smart optoelectronics. 展开更多
关键词 GaN nanowire Quantum-confined Stark effect Voltage-tunable photoresponse Bioinspired sensor Artificial vision system
在线阅读 下载PDF
Combined multidetector computed tomography and gastrointestinal endoscopy for gastric cancer screening,preoperative staging,and lymph node metastasis detection
11
作者 Le-Ping Ye Yan-Ping Zhang +4 位作者 Gang Chen Yi-Xian Wu Cheng-Long He Dong Wang Qiao Mei 《World Journal of Gastrointestinal Oncology》 2026年第1期200-210,共11页
BACKGROUND Early screening,preoperative staging,and diagnosis of lymph node metastasis are crucial for improving the prognosis of gastric cancer(GC).AIM To evaluate the diagnostic value of combined multidetector compu... BACKGROUND Early screening,preoperative staging,and diagnosis of lymph node metastasis are crucial for improving the prognosis of gastric cancer(GC).AIM To evaluate the diagnostic value of combined multidetector computed tomography(MDCT)and gastrointestinal endoscopy for GC screening,preoperative staging,and lymph node metastasis detection,thereby providing a reference for clinical diagnosis and treatment.METHODS In this retrospective study clinical and imaging data of 134 patients with suspected GC who were admitted between January 2023 and October 2024 were initially reviewed.According to the inclusion and exclusion criteria,102 patients were finally enrolled in the analysis.All enrolled patients had undergone both MDCT and gastrointestinal endoscopy examinations prior to surgical intervention.Preoperative clinical staging and lymph node metastasis findings were compared with pathological results.RESULTS The combined use of MDCT and gastrointestinal endoscopy demonstrated a sensitivity of 98.53%,specificity of 97.06%,accuracy of 98.04%,positive predictive value of 98.53%,and negative predictive value of 97.06%for diagnosing GC.These factors were all significantly higher than those of MDCT or endoscopy alone(P<0.05).The accuracy rates of the combined approach for detecting clinical T and N stages were 97.06%and 92.65%,respectively,outperforming MDCT alone(86.76% and 79.41%)and endoscopy alone(85.29% and 70.59%)(P<0.05).Among 68 patients with confirmed GC,50(73.53%)were pathologically diagnosed with lymph node metastasis.The accuracy for detecting lymph node metastasis was 66.00%with endoscopy,76.00%with MDCT,and 92.00% with the combined approach,all with statistically significant differences(P<0.05).CONCLUSION The combined application of MDCT and gastrointestinal endoscopy enhanced diagnostic accuracy for GC,provided greater consistency in preoperative staging,and improved the detection of lymph node metastasis,thereby demonstrating significant clinical utility. 展开更多
关键词 Multidetector computed tomography Gastrointestinal endoscopy Gastric cancer Preoperative staging Lymph node metastasis
暂未订购
Unveiling the origins of Northern Thailand’s haze:comprehensive chemical characterization and source apportionment of PM_(2.5) using targeted molecular markers
12
作者 Supattarachai Saksakulkrai Somporn Chantara +2 位作者 Pavidarin Kraisitnitikul Deepchandra Srivastava Zongbo Shi 《Journal of Environmental Sciences》 2026年第1期635-648,共14页
Annual haze in Northern Thailand has become increasingly severe,impacting health and the environment.How-ever,the sources of the haze remain poorly quantified due to limited observational data on aerosol molecular tra... Annual haze in Northern Thailand has become increasingly severe,impacting health and the environment.How-ever,the sources of the haze remain poorly quantified due to limited observational data on aerosol molecular tracers.This study comprehensively investigates chemical composition of PM_(2.5),including both inorganic and organic compounds throughout haze and post-haze periods in 2019 at a rural site of Northern Thailand.Average PM_(2.5) concentrations during haze and post-haze period were 87±36 and 21±11μg/m^(3),respectively.Organic matter was the dominant contributor in PM_(2.5) mass,followed by water soluble inorganic ions and mineral dust.Molecular markers,including levoglucosan,dehydroabietic acid,and 4-nitrocatechol,and ions(Cl^(-),and K^(+)),were used to characterize low haze(PM_(2.5)<100μg/m^(3))and episodic haze(PM_(2.5)>100μg/m^(3)).Low haze is associated with local aerosols from agricultural waste burning,while episodic haze is linked to aged aerosols from mixed agricultural waste,softwood,and hardwood burning.Source apportionment incorporating these molecular markers in receptor modelling(Positive matrix factorization),identified three distinct biomass burning sources:mixed,local,and aged biomass burnings,contributing 31,19 and 13%of PM_(2.5) during haze period.During post-haze period,contributions shifted,with local biomass burning(32%)comparable to secondary sulfate(34%)and mixed dust and traffic sources(26%).These findings demonstrate that both regional and local sources con-tribute to severe haze,highlighting the need for integrated policies for cross-border cooperation as well as stricter regulations to reduce biomass burning in Northern Thailand and Southeast Asia. 展开更多
关键词 Chiang Mai Smoke haze Biomass burning PM_(2.5) Source apportionment Positive matric factorization
原文传递
Flexible Monolithic 3D-Integrated Self-Powered Tactile Sensing Array Based on Holey MXene Paste
13
作者 Mengjie Wang Chen Chen +9 位作者 Yuhang Zhang Yanan Ma Li Xu Dan‑Dan Wu Bowen Gao Aoyun Song Li Wen Yongfa Cheng Siliang Wang Yang Yue 《Nano-Micro Letters》 2026年第2期772-785,共14页
Flexible electronics face critical challenges in achieving monolithic three-dimensional(3D)integration,including material compatibility,structural stability,and scalable fabrication methods.Inspired by the tactile sen... Flexible electronics face critical challenges in achieving monolithic three-dimensional(3D)integration,including material compatibility,structural stability,and scalable fabrication methods.Inspired by the tactile sensing mechanism of the human skin,we have developed a flexible monolithic 3D-integrated tactile sensing system based on a holey MXene paste,where each vertical one-body unit simultaneously functions as a microsupercapacitor and pressure sensor.The in-plane mesopores of MXene significantly improve ion accessibility,mitigate the self-stacking of nanosheets,and allow the holey MXene to multifunctionally act as a sensing material,an active electrode,and a conductive interconnect,thus drastically reducing the interface mismatch and enhancing the mechanical robustness.Furthermore,we fabricate a large-scale device using a blade-coating and stamping method,which demonstrates excellent mechanical flexibility,low-power consumption,rapid response,and stable long-term operation.As a proof-of-concept application,we integrate our sensing array into a smart access control system,leveraging deep learning to accurately identify users based on their unique pressing behaviors.This study provides a promising approach for designing highly integrated,intelligent,and flexible electronic systems for advanced human-computer interactions and personalized electronics. 展开更多
关键词 Holey MXene Microsupercapacitor Tactile sensor Monolithic 3D integration Deep learning algorithm
在线阅读 下载PDF
Taxonomic classification of 80 near-Earth asteroids
14
作者 Fan Mo Bin Li +9 位作者 HaiBin Zhao Jian Chen Yan Jin MengHui Tang Igor Molotov A.M.Abdelaziz A.Takey S.K.Tealib Ahmed.Shokry JianYang Li 《Earth and Planetary Physics》 2026年第1期196-204,共9页
Near-Earth objects are important not only in studying the early formation of the Solar System,but also because they pose a serious hazard to humanity when they make close approaches to the Earth.Study of their physica... Near-Earth objects are important not only in studying the early formation of the Solar System,but also because they pose a serious hazard to humanity when they make close approaches to the Earth.Study of their physical properties can provide useful information on their origin,evolution,and hazard to human beings.However,it remains challenging to investigate small,newly discovered,near-Earth objects because of our limited observational window.This investigation seeks to determine the visible colors of near-Earth asteroids(NEAs),perform an initial taxonomic classification based on visible colors and analyze possible correlations between the distribution of taxonomic classification and asteroid size or orbital parameters.Observations were performed in the broadband BVRI Johnson−Cousins photometric system,applied to images from the Yaoan High Precision Telescope and the 1.88 m telescope at the Kottamia Astronomical Observatory.We present new photometric observations of 84 near-Earth asteroids,and classify 80 of them taxonomically,based on their photometric colors.We find that nearly half(46.3%)of the objects in our sample can be classified as S-complex,26.3%as C-complex,6%as D-complex,and 15.0%as X-complex;the remaining belong to the A-or V-types.Additionally,we identify three P-type NEAs in our sample,according to the Tholen scheme.The fractional abundances of the C/X-complex members with absolute magnitude H≥17.0 were more than twice as large as those with H<17.0.However,the fractions of C-and S-complex members with diameters≤1 km and>1 km are nearly equal,while X-complex members tend to have sub-kilometer diameters.In our sample,the C/D-complex objects are predominant among those with a Jovian Tisserand parameter of T_(J)<3.1.These bodies could have a cometary origin.C-and S-complex members account for a considerable proportion of the asteroids that are potentially hazardous. 展开更多
关键词 near-Earth asteroids optical telescope photometric observation taxonomic classification
在线阅读 下载PDF
Assessing ability of a wet swale to manage road runoff:A case study in Hefei, China 被引量:3
15
作者 唐宁远 李田 葛军 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第6期1353-1362,共10页
The ability of a wet swale,constructed in an area of poor soil permeability,to manage runoff from a roadway was monitored through 27 storm events over a period of 8 months.During the monitoring period,the wet swale re... The ability of a wet swale,constructed in an area of poor soil permeability,to manage runoff from a roadway was monitored through 27 storm events over a period of 8 months.During the monitoring period,the wet swale reduced the total runoff volume by 50.4%through exfiltration and evapotranspiration.The wet swale significantly decreased the influent pollutant concentrations,and the effluent mean concentrations of total suspended solids,total phosphorus,chemical oxygen demand,ammonium,oxidized nitrogen,and total nitrogen in the effluent were 31 mg/L,0.10 mg/L,29 mg/L,0.52 mg/L,0.35 mg/L and1.28 mg/L,respectively.Pollutant loads were also substantially reduced from 70%to 85%.Plant uptake played an important role in nutrient removal in the wet swale.Approximately half of the nitrogen(53.8%)and phosphorus(51.5%)that entered the wet swale was incorporated in above-ground plants.It is shown that wet swales are useful for managing runoff from roads in areas of poor soil permeability. 展开更多
关键词 wet swale stormwater runoff water quality improvement water quantity reduction removal mechanism VEGETATION
在线阅读 下载PDF
Butterfly taxonomic and functional diversity in the urban green spaces of Hefei city
16
作者 Haicong Zeng Yan Zhu +5 位作者 Junyao Zhang Chenliang Li Jian Zhang Hui Liu Jianan Wang Dexian Zhao 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期47-62,共16页
Urbanization has profound impacts on ecological environments. Green spaces are a vital component of urban ecosystems and play a crucial role in maintaining ecological balance and enhancing sustainability. This study a... Urbanization has profound impacts on ecological environments. Green spaces are a vital component of urban ecosystems and play a crucial role in maintaining ecological balance and enhancing sustainability. This study aimed to investigate the community composition characteristics of butterflies in urban green spaces within the context of rapid urbanization. Simultaneously, it explored the status and differences in butterfly taxonomic diversity, functional diversity, and functional traits among different types of urban green spaces, regions, and urban gradients to provide relevant insights for further improving urban green space quality and promoting biodiversity conservation. We conducted a year-long survey of 80 green spaces across different urban regions and ring roads within Hefei City, Anhui Province, with monthly sampling intervals over 187 transects. A total of 4822 butterflies, belonging to 5 families, 17 subfamilies, 40 genera, and 55 species were identified. The species richness, Shannon, Simpson, functional richness, and Rao's quadratic entropy indices of butterflies in urban park green spaces were all significantly higher than those in residential and street green spaces(P < 0.05). Differences in butterfly diversity and functional traits among different urban regions and ring roads were relatively minor, and small-sized, multivoltine, and long flying duration butterflies dominated urban green spaces. Overall, these spaces offer more favorable habitats for butterflies. However, some residential green spaces and street green spaces demonstrate potential for butterfly conservation. 展开更多
关键词 Urban green space planning Rapid urbanization Butterfly functional traits Green space types Urban biodiversity
在线阅读 下载PDF
Exploring Nanoscale Perovskite Materials for Next‑Generation Photodetectors:A Comprehensive Review and Future Directions 被引量:2
17
作者 Xin Li Sikandar Aftab +4 位作者 Maria Mukhtar Fahmid Kabir Muhammad Farooq Khan Hosameldin Helmy Hegazy Erdi Akman 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期46-108,共63页
The rapid advancement of nanotechnology has sparked much interest in applying nanoscale perovskite materials for photodetection applications.These materials are promising candidates for next-generation photodetectors(... The rapid advancement of nanotechnology has sparked much interest in applying nanoscale perovskite materials for photodetection applications.These materials are promising candidates for next-generation photodetectors(PDs)due to their unique optoelectronic properties and flexible synthesis routes.This review explores the approaches used in the development and use of optoelectronic devices made of different nanoscale perovskite architectures,including quantum dots,nanosheets,nanorods,nanowires,and nanocrystals.Through a thorough analysis of recent literature,the review also addresses common issues like the mechanisms underlying the degradation of perovskite PDs and offers perspectives on potential solutions to improve stability and scalability that impede widespread implementation.In addition,it highlights that photodetection encompasses the detection of light fields in dimensions other than light intensity and suggests potential avenues for future research to overcome these obstacles and fully realize the potential of nanoscale perovskite materials in state-of-the-art photodetection systems.This review provides a comprehensive overview of nanoscale perovskite PDs and guides future research efforts towards improved performance and wider applicability,making it a valuable resource for researchers. 展开更多
关键词 Nanoscale perovskites PHOTODETECTORS NANOSHEETS NANORODS NANOWIRES Quantum dots NANOCRYSTALS
在线阅读 下载PDF
Polyamino acid-mediated crystallization and crystal stabilization in perovskite for efficient and stable photovoltaic devices 被引量:1
18
作者 Chaoyang Wu Chao Wang +3 位作者 Feifan Chen Xinhe Dong Jiajiu Ye Haiying Zheng 《Journal of Semiconductors》 2025年第5期103-111,共9页
Although perovskite solar cells(PSCs) demonstrate outstanding power conversion efficiency(PCE), their practical applications are still limited by stability issues caused by various problems such as poor crystal qualit... Although perovskite solar cells(PSCs) demonstrate outstanding power conversion efficiency(PCE), their practical applications are still limited by stability issues caused by various problems such as poor crystal quality triggered structural instability. Herein, to address the structural instability of perovskites, we introduced a polymer additive, poly-L-lysine hydrobromide(PLL), into the perovskite precursor to promote perovskite crystal growth, thereby constructing a stable crystal structure. The results show that the introduction of PLL modulates the colloidal aggregation state in the precursor solution, provides longer time for growth of perovskite and successfully realizes the formation of large-sized perovskite films with high crystallinity. More importantly, owing to its hydrophobic long-chain structure and the widespread distribution of C=O and NH on the chain, PLL firmly locks the perovskite crystals, enhancing their structural stability while blocking the intrusion of external factors such as water molecules, significantly enhances the overall stability of the device. The results show that the PLL-based PSC has negligible hysteresis and its PCE is improved from 22.20% to 23.66%. while the PLL-modified perovskite films and devices demonstrate excellent thermal and environmental stability. These findings highlight PLL as a promising additive for optimizing perovskite crystallization, offering guidance for fabricating efficient and stable photovoltaic devices. 展开更多
关键词 perovskite solar cells polyamino acid ADDITIVE CRYSTALLIZATION stability
在线阅读 下载PDF
Spatial-temporal distribution and emission of urban scale air pollutants in Hefei based on Mobile-DOAS 被引量:1
19
作者 Zhidong Zhang Pinhua Xie +8 位作者 Ang Li Min Qin Jin Xu Zhaokun Hu Xin Tian Feng Hu Yinsheng Lv Jiangyi Zheng Youtao Li 《Journal of Environmental Sciences》 2025年第5期238-251,共14页
As a significant city in the Yangtze River Delta regions,Hefei has experienced rapid changes in the sources of air pollution due to its high-speed economic development and urban expansion.However,there has been limite... As a significant city in the Yangtze River Delta regions,Hefei has experienced rapid changes in the sources of air pollution due to its high-speed economic development and urban expansion.However,there has been limited research in recent years on the spatial-temporal distribution and emission of its atmospheric pollutants.To address this,this study conducted mobile observations of urban roads using the Mobile-DOAS instrument from June 2021 to May 2022.The monitoring results exhibit a favourable consistent with TROPOMI satellite data and ground monitoring station data.Temporally,there were pronounced seasonal variations in air pollutants.Spatially,high concentration of HCHO and NO_(2)were closely associated with traffic congestion on roadways,while heightened SO_(2)levels were attributed to winter heating and industrial emissions.The study also revealed that with the implementation of road policies,the average vehicle speed increased by 95.4%,while the NO concentration decreased by 54.4%.In the estimation of urban NO_(x)emission flux,it was observed that in temporal terms,compared with inventory data,the emissions calculated viamobile measurements exhibitedmore distinct seasonal patterns,with the highest emission rate of 349 g/sec in winter and the lowest of 142 g/sec in summer.In spatial terms,the significant difference in emissions between the inner and outer ring roads also suggests the presence of the city’s primary NO_(x)emission sources in the area between these two rings.This study offers data support for formulating the next phase of air pollution control measures in urban areas. 展开更多
关键词 Mobile-DOAS HCHO NO_(2) SO_(2) Spatial-temporal distribution NOx emission
原文传递
Novel homozygous SPAG17 variants cause human male infertility through multiple morphological abnormalities of spermatozoal flagella related to axonemal microtubule doublets 被引量:1
20
作者 Tao Liu Fazal Rahim +15 位作者 Meng-Lei Yang Meftah Uddin Jing-Wei Ye Imtiaz Ali Yousaf Raza Abu Mansoor Muhammad Shoaib Mujahid Hussain Ihsan Khan Basit Shah Asad Khan Ahmad Nisar Hui Ma Bo Xu Wasim Shah Qing-Hua Shi 《Asian Journal of Andrology》 2025年第2期245-253,共9页
Male infertility can result from impaired sperm motility caused by multiple morphological abnormalities of the flagella(MMAF).Distinct projections encircling the central microtubules of the spermatozoal axoneme play p... Male infertility can result from impaired sperm motility caused by multiple morphological abnormalities of the flagella(MMAF).Distinct projections encircling the central microtubules of the spermatozoal axoneme play pivotal roles in flagellar bending and spermatozoal movement.Mammalian sperm-associated antigen 17(SPAG17)encodes a conserved axonemal protein of cilia and flagella,forming part of the C1a projection of the central apparatus,with functions related to ciliary/flagellar motility,skeletal growth,and male fertility.This study investigated two novel homozygous SPAG17 mutations(M1:NM_206996.2,c.829+1G>T,p.Asp212_Glu276del;and M2:c.2120del,p.Leu707*)identified in four infertile patients from two consanguineous Pakistani families.These patients displayed the MMAF phenotype confirmed by Papanicolaou staining and scanning electron microscopy assays of spermatozoa.Quantitative real-time polymerase chain reaction(PCR)of patients’spermatozoa also revealed a significant decrease in SPAG17 mRNA expression,and immunofluorescence staining showed the absence of SPAG17 protein signals along the flagella.However,no apparent ciliary-related symptoms or skeletal malformations were observed in the chest X-rays of any of the patients.Transmission electron microscopy of axoneme cross-sections from the patients showed incomplete C1a projection and a higher frequency of missing microtubule doublets 1 and 9 compared with those from fertile controls.Immunofluorescence staining and Western blot analyses of spermatogenesis-associated protein 17(SPATA17),a component of the C1a projection,and sperm-associated antigen 6(SPAG6),a marker of the spring layer,revealed disrupted expression of both proteins in the patients’spermatozoa.Altogether,these findings demonstrated that SPAG17 maintains the integrity of spermatozoal flagellar axoneme,expanding the phenotypic spectrum of SPAG17 mutations in humans. 展开更多
关键词 C1a projection central apparatus male infertility multiple morphological abnormalities of the flagella SPAG17
原文传递
上一页 1 2 250 下一页 到第
使用帮助 返回顶部