Microscopy imaging is fundamental in analyzing bacterial morphology and dynamics,offering critical insights into bacterial physiology and pathogenicity.Image segmentation techniques enable quantitative analysis of bac...Microscopy imaging is fundamental in analyzing bacterial morphology and dynamics,offering critical insights into bacterial physiology and pathogenicity.Image segmentation techniques enable quantitative analysis of bacterial structures,facilitating precise measurement of morphological variations and population behaviors at single-cell resolution.This paper reviews advancements in bacterial image segmentation,emphasizing the shift from traditional thresholding and watershed methods to deep learning-driven approaches.Convolutional neural networks(CNNs),U-Net architectures,and three-dimensional(3D)frameworks excel at segmenting dense biofilms and resolving antibiotic-induced morphological changes.These methods combine automated feature extraction with physics-informed postprocessing.Despite progress,challenges persist in computational efficiency,cross-species generalizability,and integration with multimodal experimental workflows.Future progress will depend on improving model robustness across species and imaging modalities,integrating multimodal data for phenotype-function mapping,and developing standard pipelines that link computational tools with clinical diagnostics.These innovations will expand microbial phenotyping beyond structural analysis,enabling deeper insights into bacterial physiology and ecological interactions.展开更多
Desulfurization of CaO–Al_(2)O_(3) particles in molten steel was observed in situ using high-temperature confocal scanning laser microscopy.The effects of the aluminum and silicon contents of molten steel on desulfur...Desulfurization of CaO–Al_(2)O_(3) particles in molten steel was observed in situ using high-temperature confocal scanning laser microscopy.The effects of the aluminum and silicon contents of molten steel on desulfurization were analyzed.When the total aluminum content in the steel increased from 6 to 1100 ppm,the CaS content in CaO–Al_(2)O_(3) particles increased from 2.1wt%to 84.84wt%after the reaction for 90 s.Furthermore,when the silicon content in the steel increased from 0.01wt%to 2.20wt%,the CaS content in CaO–Al_(2)O_(3) particles increased from 1.53wt%to 79.01wt%after the reaction for 90 s.This indicates that the increase in the aluminum and silicon contents of the steel promoted the desulfurization of CaO–Al_(2)O_(3) particles.A kinetic model was established to predict the CaO–Al_(2)O_(3) particles composition,and the diffusion coefficient of sulfur in CaO–Al_(2)O_(3) particles was 9.375×10^(−10)m^(2)·s^(−1) at 1600℃,which provided a new method for the calculation of diffusion coefficient.展开更多
【目的】探究温拌沥青混合料黏附机理,拓展温拌沥青与集料黏附性研究方法。【方法】使用原子力显微镜(atomic force microscope,AFM)测得分别加入Sasobit类温拌剂H01(质量分数分别为1.0%、3.0%、5.0%)和表面活性剂类温拌剂H02(质量分数...【目的】探究温拌沥青混合料黏附机理,拓展温拌沥青与集料黏附性研究方法。【方法】使用原子力显微镜(atomic force microscope,AFM)测得分别加入Sasobit类温拌剂H01(质量分数分别为1.0%、3.0%、5.0%)和表面活性剂类温拌剂H02(质量分数分别为0.3%、0.5%、0.7%)的温拌沥青试样黏附力,并经JKR(Johnson-Kendall-Roberts)模型和表面能理论将其转换为沥青表面能,计算沥青-花岗岩和沥青-玄武岩体系的无水、有水黏附功,并与水煮试验、水稳定性试验结果进行对比分析;对基于AFM测得的温拌沥青退针力曲线进行积分,得到黏附性指标G,并将其与沥青表面能进行相关性拟合。【结果】两类温拌剂的加入均降低了温拌沥青-集料体系的黏附功,温拌沥青-花岗岩体系的无水黏附功比温拌沥青-玄武岩体系的大,有水黏附功则相反;基于AFM求解得到的H01温拌沥青-玄武岩体系黏附功的变化趋势与水稳定性试验结果相同,而H02温拌沥青-玄武岩体系的则相反;黏附性指标G与沥青表面能之间具有较好的相关性。【结论】相比温拌沥青-玄武岩体系,温拌沥青-花岗岩体系更容易发生水损害;基于AFM求解沥青-玄武岩体系黏附功的方法适用于Sasobit类温拌沥青,不适用于表面活性剂类温拌沥青;本文提出的黏附性指标G为评价温拌沥青-集料体系黏附性提供了新的量化指标。展开更多
Atomic force microscopy(AFM) is a commonly used technique for graphene thickness measurement.However, due to surface roughness caused by graphene itself and variation introduced in AFM measurement, graphene thicknes...Atomic force microscopy(AFM) is a commonly used technique for graphene thickness measurement.However, due to surface roughness caused by graphene itself and variation introduced in AFM measurement, graphene thickness is difficult to be accurately determined by AFM. In this paper, a histogram method was used for reliable measurements of graphene thickness using AFM. The influences of various measurement parameters in AFM analysis were investigated. The experimental results indicate that significant deviation can be introduced using various order of flatten and improperly selected measurement parameters including amplitude setpoint and drive amplitude. At amplitude setpoint of 100 mV and drive amplitude of 100 m V, thickness of 1 layer(1L), 2 layers(2L) and 4 layers(4L) graphene were measured.The height differences for 1L, 2L and 4L were 1.51 ± 0.16 nm, 1.92 ± 0.13 nm and 2.73 ± 0.10 nm, respectively. By comparing these values, thickness of single layer graphene can be accurately determined to be0.41 ± 0.09 nm.展开更多
An improved arc discharge method is developed to fabricate carbon nanotube probe of atomic force microscopy (AFM) here. First, silicon probe and carbon nanotube are manipulated under an optical microscope by two hig...An improved arc discharge method is developed to fabricate carbon nanotube probe of atomic force microscopy (AFM) here. First, silicon probe and carbon nanotube are manipulated under an optical microscope by two high precision microtranslators. When silicon probe and carbon nanotube are very close, several tens voltage is applied between them. And carbon nanotube is divided and attached to the end of silicon probe, which mainly due to the arc welding function. Comparing with the arc discharge method before, the new method here needs no coat silicon probe with metal film in advance, which can greatly reduce the fabrication's difficulty. The fabricated carbon nanotube probe shows good property of higher aspect ratio and can more accurately reflect the true topography of silicon grating than silicon probe. Under the same image drive force, carbon nanotube probe had less indentation depth on soft triblock copolymer sample than silicon probe. This showed that carbon nanotube probe has lower spring constant and less damage to the scan sample than silicon probe.展开更多
The organization of the higher order structure of chromatin in chicken erythrocytes has been examined withtapping-mode scanning force microscopy under conditionsclose to their native environment. Reproducible highreso...The organization of the higher order structure of chromatin in chicken erythrocytes has been examined withtapping-mode scanning force microscopy under conditionsclose to their native environment. Reproducible highresolution AFM images of chromatin compaction at several levels can be demonstrated. An extended beads-on-astring (width of ~ 15-20nm, height of ~ 2-3nm for eachindividual nucleosome) can be consistently observed. Furthermore, superbeads (width of ~ 40nm, height of ~ 7nm)are demonstrated. Visualization of the solenoid conformation at the level of 30nm chromatin fiber is attained eitherby using AFM or by using electron microscopy. In addition, tightly coiled chromatin fibers (~ 50-60nm and ~90-110nm) can be revealed. Our data suggest that the chromatin in the interphase nucleus of chicken erythrocyte represents a high-order conformation and AFM provides useful high-resolution structural information concerning thefolding pattern of interphase chromatin fibers.展开更多
Si/SiC heterostructures with different growth temperatures were prepared on 6 HSiC(0001)by LPCVD.Current mode atomic force microscopy and transmission electron microscopy were employed to investigate the electrical pr...Si/SiC heterostructures with different growth temperatures were prepared on 6 HSiC(0001)by LPCVD.Current mode atomic force microscopy and transmission electron microscopy were employed to investigate the electrical properties and crystalline structure of Si/SiC heterostructures.Face-centered cubic(FCC)on hexagonal close-packing(HCP)epitaxy of the Si(111)/SiC(0001)heterostructure was realized at 900°C.As the growth temperature increases to1050°C,the<110>preferred orientation of the Si film is observed.The Si films on 6 H-SiC(0001)with different growth orientations consist of different distinctive crystalline grains:quasi-spherical grains with a general size of 20μm,and columnar grains with a typical size of 7μm×20μm.The electrical properties are greatly influenced by the grain structures.The Si film with<110>orientation on SiC(0001)consists of columnar grains,which is more suitable for the fabrication of Si/SiC devices due to its low current fluctuation and relatively uniform current distribution.展开更多
The characteristics of nonmetallic inclusions formed during steel production have a significant influence on steel performance.In this paper,studies on inclusions using confocal scanning laser microscopy(CSLM)are revi...The characteristics of nonmetallic inclusions formed during steel production have a significant influence on steel performance.In this paper,studies on inclusions using confocal scanning laser microscopy(CSLM)are reviewed and summarized,particularly the col-lision of various inclusions,dissolution of inclusions in liquid slag,and reactions between inclusions and steel.Solid inclusions exhibited a high collision tendency,whereas pure liquid inclusions exhibited minimal collisions because of the small attraction force induced by their<90°contact angle with molten steel.The collision of complex inclusions in molten steel was not included in the scope of this study and should be evaluated in future studies.Higher CaO/Al_(2)O_(3)and CaO/SiO_(2)ratios in liquid slag promoted the dissolution of Al_(2)O_(3)-based in-clusions.The formation of solid phases in the slag should be prevented to improve dissolution of inclusions.To accurately simulate the dissolution of inclusions in liquid slag,in-situ observation of the dissolution of inclusions at the steel-slag interface is necessary.Using a combination of CSLM and scanning electron microscopy-energy dispersive spectroscopy,the composition and morphological evolution of the inclusions during their modification by the dissolved elements in steel were observed and analyzed.Although the in-situ observa-tion of MnS and TiN precipitations has been widely studied,the in-situ observation of the evolution of oxide inclusions in steel during so-lidification and heating processes has rarely been reported.The effects of temperature,heating and cooling rates,and inclusion character-istics on the formation of acicular ferrites(AFs)have been widely studied.At a cooling rate of 3-5 K/s,the order of AF growth rate in-duced by different inclusions,as reported in literature,is Ti-O<Ti-Ca-Zr-Al-O<Mg-O<Ti-Zr-Al-O<Mn-Ti-Al-O<Ti-Al-O<Zr-Ti-Al-O.Further comprehensive experiments are required to investigate the quantitative relationship between the formation of AFs and inclusions.展开更多
Objective:Verrucous epidermal nevus(VEN),seborrheic keratosis(SK),verruca plana(VP),verruca vulgaris(VV),and nevus sebaceous(NS)are common verrucous proliferative skin diseases with similar clinical appearances,often ...Objective:Verrucous epidermal nevus(VEN),seborrheic keratosis(SK),verruca plana(VP),verruca vulgaris(VV),and nevus sebaceous(NS)are common verrucous proliferative skin diseases with similar clinical appearances,often posing diagnostic challenges.Dermoscopy and reflectance confocal microscopy(RCM)can aid in their differentiation,yet their specific features under these tools have not been systematically described.This study aims to summarize and analyze the dermoscopic and RCM features of VEN,SK,VP,VV,and NS.Methods:A total of 121 patients with histopathologically confirmed verrucous proliferative skin diseases were enrolled.Dermoscopy and RCM imaging was used to observe and analyze the microscopic features of these conditions.Results:Under dermoscopy,the 5 diseases displayed distinct characteristics:VEN typically showed gyriform structures;SK was characterized by gyriform structures,comedo-like openings,and milia-like cysts;VP and VV featured dotted vessels and frogspawn-like structures;NS presented as brownish-yellow globules.RCM revealed shared features such as hyperkeratosis and acanthosis across all 5 diseases.Specific features included gyriform structures and elongated rete ridges in VEN;pseudocysts and gyriform structures in SK;evenly distributed ring-like structures in VP;vacuolated cells and papillomatous proliferation in VV;and frogspawn-like structures in NS.Conclusion:These 5 verrucous proliferative skin conditions exhibit distinguishable features under both dermoscopy and RCM.The combination of these 2 noninvasive imaging modalities holds significant clinical value for the differential diagnosis of verrucous proliferative skin diseases.展开更多
Recently,charged solitons have been found in a two-dimensional CoCl_(2)/HOPG system,whose microscopic nature remains to be elusive.In this work,we investigate the charged solitons in monolayer CoCl_(2) using scanning ...Recently,charged solitons have been found in a two-dimensional CoCl_(2)/HOPG system,whose microscopic nature remains to be elusive.In this work,we investigate the charged solitons in monolayer CoCl_(2) using scanning tunneling microscopy(STM)and atomic force microscopy(AFM).Moreover,we study the electrical properties of the charged solitons at zero electric field by measuring local contact potential difference(LCPD)via Kelvin probe force microscopy(KPFM)using the Δf(V)method.The compensation voltage corresponding to the vertex of the parabola is obtained by fitting the quadratic relationship between Δf and sample bias.The results show that,without an external electric field,the solitons behave as negatively charged entities.Meanwhile,the LCPD mapping characterizes the spatial distribution of the potential at the charged solitons,which agrees well with those obtained from STM band bending measurements.展开更多
Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution fo...Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution for high-throughput digital pathology,combining high resolution,large field of view,and extended depth of field(DOF).However,the full-color capabilities of FPM are hindered by coherent color artifacts and reduced computational efficiency,which significantly limits its practical applications.Color-transferbased FPM(CFPM)has emerged as a potential solution,theoretically reducing both acquisition and reconstruction threefold time.Yet,existing methods fall short of achieving the desired reconstruction speed and colorization quality.In this study,we report a generalized dual-color-space constrained model for FPM colorization.This model provides a mathematical framework for model-based FPM colorization,enabling a closed-form solution without the need for redundant iterative calculations.Our approach,termed generalized CFPM(gCFPM),achieves colorization within seconds for megapixel-scale images,delivering superior colorization quality in terms of both colorfulness and sharpness,along with an extended DOF.Both simulations and experiments demonstrate that gCFPM surpasses state-of-the-art methods across all evaluated criteria.Our work offers a robust and comprehensive workflow for high-throughput full-color pathological imaging using FPM platforms,laying a solid foundation for future advancements in methodology and engineering.展开更多
In this work, we investigate the Co-Si reaction, the Co growth mode at room temperature, diffusion be- haviour as well as morphology evolution during annealing on both H-terminated and clean Si(001) and Si(111) sur- f...In this work, we investigate the Co-Si reaction, the Co growth mode at room temperature, diffusion be- haviour as well as morphology evolution during annealing on both H-terminated and clean Si(001) and Si(111) sur- faces. From in-situ X-ray photoelectron spectroscopy (XPS) investigation, “Co-Si” reaction appears to occur on both H-terminated and clean surfaces at room temperature (RT) and the silicide crystallinity is improved upon annealing. Co growth mode on H-terminated Si surfaces occurs in a pseudo layer-by-layer manner while small close-packed is- land growth mode is observed on the clean Si surface. Upon annealing at different temperatures, Co atom concentra- tion decreases versus annealing time, which in part is attributed to Co atoms inward diffusion. The diffusion behav- iour on both types of surfaces demonstrates a similar trend. Morphology study using ex-situ atomic force microscopy (AFM) shows that the islands formed on Si(001) surface after annealing at 700 °C are elongated with growth direc- tions alternate between the two perpendicular [ 110 ] and [110] directions. Triangular islands are observed on Si (111) surface.展开更多
High-resolution transmission electron microscopy(HRTEM)promises rapid atomic-scale dynamic structure imaging.Yet,the precision limitations of aberration parameters and the challenge of eliminating aberrations in Cs-co...High-resolution transmission electron microscopy(HRTEM)promises rapid atomic-scale dynamic structure imaging.Yet,the precision limitations of aberration parameters and the challenge of eliminating aberrations in Cs-corrected transmission electron microscopy constrain resolution.A machine learning algorithm is developed to determine the aberration parameters with higher precision from small,lattice-periodic crystal images.The proposed algorithm is then validated with simulated HRTEM images of graphene and applied to the experimental images of a molybdenum disulfide(MoS_(2))monolayer with 25 variables(14 aberrations)resolved in wide ranges.Using these measured parameters,the phases of the exit-wave functions are reconstructed for each image in a focal series of MoS_(2)monolayers.The images were acquired due to the unexpected movement of the specimen holder.Four-dimensional data extraction reveals time-varying atomic structures and ripple.In particular,the atomic evolution of the sulfur-vacancy point and line defects,as well as the edge structure near the amorphous,is visualized as the resolution has been improved from about 1.75?to 0.9 A.This method can help salvage important transmission electron microscope images and is beneficial for the images obtained from electron microscopes with average stability.展开更多
To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral cortex.However,these me...To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral cortex.However,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly age-related.In this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed laser.We observed the molding process in mice of different ages and presented age-dependent vascular embolism differentiation.Moreover,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a stroke.Our imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes.展开更多
Stochastic optical reconstruction microscopy(STORM),as a typical technique of single-molecule localization microscopy(SMLM),has overcome the diffraction limit by randomly switching fluorophores between fluorescent and...Stochastic optical reconstruction microscopy(STORM),as a typical technique of single-molecule localization microscopy(SMLM),has overcome the diffraction limit by randomly switching fluorophores between fluorescent and dark states,allowing for the precise localization of isolated emission patterns and the super-resolution reconstruction from millions of localized positions of single fluorophores.A critical factor influencing localization precision is the photo-switching behavior of fluorophores,which is affected by the imaging buffer.The imaging buffer typically comprises oxygen scavengers,photo-switching reagents,and refractive index regulators.Oxygen scavengers help prevent photobleaching,photo-switching reagents assist in facilitating the conversion of fluorophores,and refractive index regulators are used to adjust the refractive index of the solution.The synergistic interaction of these components promotes stable blinking of fluorophores,reduces irreversible photobleaching,and thereby ensures high-quality super-resolution imaging.This review provides a comprehensive overview of the essential compositions and functionalities of imaging buffers used in STORM,serving as a valuable resource for researchers seeking to select appropriate imaging buffers for their experiments.展开更多
The photocatalytic activity of a photocatalyst is significantly influenced by its microstructure.Therefore,it is crucial to understand and characterize the microstructure.Transmission electron microscopy(TEM)has been ...The photocatalytic activity of a photocatalyst is significantly influenced by its microstructure.Therefore,it is crucial to understand and characterize the microstructure.Transmission electron microscopy(TEM)has been an indispensable tool that provides direct visualization of the microstructure at the atomic level.Despite numerous reviews on photocatalytic processes,there has been a lack of comprehensive summaries that focus on the critical role of TEM in photocatalytic applications.This review aims to fill this gap by highlighting the significant contributions of TEM techniques in understanding key photocatalytic processes,including light absorption,charge separation and transfer,and surface reaction.In addition,this review discusses in-situ TEM techniques for observing photocatalytic reactions and explores the challenges and future perspectives related to the application of TEM in photocatalysis.展开更多
Fine particle detachment and subsequent migration can lead to severe pore plugging and consequent permeability decline.Therefore,it is crucial to quantify the critical condition when fine particle detachment occurs.Th...Fine particle detachment and subsequent migration can lead to severe pore plugging and consequent permeability decline.Therefore,it is crucial to quantify the critical condition when fine particle detachment occurs.The frequently observed deviations or even contradictions between experimental results and theoretical predictions of fines detachment arise from an insufficient understanding of adhesion force that can be highly influenced by salinity and temperature.To clarify the intrinsic influence of salinity and temperature on fines detachment,adhesion forces between carboxyl microspheres and hydrophilic silica substrates in an aqueous medium were measured at various salinities and tempera-tures using atomic force microscopy(AFM).The AFM-measured adhesion force decreases with increasing salinity or temperature.Trends of mean measured adhesion forces with temperature and salinity were compared with the DLVO and XDLVO theories.DLVO theory captured the trend with temperature via the impact of temperature on electric double layer interactions,whereas XDLVO theory captured the observed trend with salinity via the impact of salinity on the repulsive hydration force.Our results highlight the significance of hydration force in accurately predicting the fate of fines in porous media.展开更多
基金financially supported by the Open Project Program of Wuhan National Laboratory for Optoelectronics(No.2022WNLOKF009)the National Natural Science Foundation of China(No.62475216)+2 种基金the Key Research and Development Program of Shaanxi(No.2024GH-ZDXM-37)the Fujian Provincial Natural Science Foundation of China(No.2024J01060)the Startup Program of XMU,and the Fundamental Research Funds for the Central Universities.
文摘Microscopy imaging is fundamental in analyzing bacterial morphology and dynamics,offering critical insights into bacterial physiology and pathogenicity.Image segmentation techniques enable quantitative analysis of bacterial structures,facilitating precise measurement of morphological variations and population behaviors at single-cell resolution.This paper reviews advancements in bacterial image segmentation,emphasizing the shift from traditional thresholding and watershed methods to deep learning-driven approaches.Convolutional neural networks(CNNs),U-Net architectures,and three-dimensional(3D)frameworks excel at segmenting dense biofilms and resolving antibiotic-induced morphological changes.These methods combine automated feature extraction with physics-informed postprocessing.Despite progress,challenges persist in computational efficiency,cross-species generalizability,and integration with multimodal experimental workflows.Future progress will depend on improving model robustness across species and imaging modalities,integrating multimodal data for phenotype-function mapping,and developing standard pipelines that link computational tools with clinical diagnostics.These innovations will expand microbial phenotyping beyond structural analysis,enabling deeper insights into bacterial physiology and ecological interactions.
基金supported by the National Key R&D Program of China(No.2023YFB3709900)the National Nature Science Foundation of China(No.U22A20171)+1 种基金the China Baowu Low Carbon Metallurgy Innovation Foundation(No.BWLCF202315)the High Steel Center(HSC)at North China University of Technology and University of Science and Technology Beijing,China.
文摘Desulfurization of CaO–Al_(2)O_(3) particles in molten steel was observed in situ using high-temperature confocal scanning laser microscopy.The effects of the aluminum and silicon contents of molten steel on desulfurization were analyzed.When the total aluminum content in the steel increased from 6 to 1100 ppm,the CaS content in CaO–Al_(2)O_(3) particles increased from 2.1wt%to 84.84wt%after the reaction for 90 s.Furthermore,when the silicon content in the steel increased from 0.01wt%to 2.20wt%,the CaS content in CaO–Al_(2)O_(3) particles increased from 1.53wt%to 79.01wt%after the reaction for 90 s.This indicates that the increase in the aluminum and silicon contents of the steel promoted the desulfurization of CaO–Al_(2)O_(3) particles.A kinetic model was established to predict the CaO–Al_(2)O_(3) particles composition,and the diffusion coefficient of sulfur in CaO–Al_(2)O_(3) particles was 9.375×10^(−10)m^(2)·s^(−1) at 1600℃,which provided a new method for the calculation of diffusion coefficient.
文摘【目的】探究温拌沥青混合料黏附机理,拓展温拌沥青与集料黏附性研究方法。【方法】使用原子力显微镜(atomic force microscope,AFM)测得分别加入Sasobit类温拌剂H01(质量分数分别为1.0%、3.0%、5.0%)和表面活性剂类温拌剂H02(质量分数分别为0.3%、0.5%、0.7%)的温拌沥青试样黏附力,并经JKR(Johnson-Kendall-Roberts)模型和表面能理论将其转换为沥青表面能,计算沥青-花岗岩和沥青-玄武岩体系的无水、有水黏附功,并与水煮试验、水稳定性试验结果进行对比分析;对基于AFM测得的温拌沥青退针力曲线进行积分,得到黏附性指标G,并将其与沥青表面能进行相关性拟合。【结果】两类温拌剂的加入均降低了温拌沥青-集料体系的黏附功,温拌沥青-花岗岩体系的无水黏附功比温拌沥青-玄武岩体系的大,有水黏附功则相反;基于AFM求解得到的H01温拌沥青-玄武岩体系黏附功的变化趋势与水稳定性试验结果相同,而H02温拌沥青-玄武岩体系的则相反;黏附性指标G与沥青表面能之间具有较好的相关性。【结论】相比温拌沥青-玄武岩体系,温拌沥青-花岗岩体系更容易发生水损害;基于AFM求解沥青-玄武岩体系黏附功的方法适用于Sasobit类温拌沥青,不适用于表面活性剂类温拌沥青;本文提出的黏附性指标G为评价温拌沥青-集料体系黏附性提供了新的量化指标。
基金supported by the Program of National Key Technology R&D Program of the Ministry of Science and Technology of China(2011BAK15B04)
文摘Atomic force microscopy(AFM) is a commonly used technique for graphene thickness measurement.However, due to surface roughness caused by graphene itself and variation introduced in AFM measurement, graphene thickness is difficult to be accurately determined by AFM. In this paper, a histogram method was used for reliable measurements of graphene thickness using AFM. The influences of various measurement parameters in AFM analysis were investigated. The experimental results indicate that significant deviation can be introduced using various order of flatten and improperly selected measurement parameters including amplitude setpoint and drive amplitude. At amplitude setpoint of 100 mV and drive amplitude of 100 m V, thickness of 1 layer(1L), 2 layers(2L) and 4 layers(4L) graphene were measured.The height differences for 1L, 2L and 4L were 1.51 ± 0.16 nm, 1.92 ± 0.13 nm and 2.73 ± 0.10 nm, respectively. By comparing these values, thickness of single layer graphene can be accurately determined to be0.41 ± 0.09 nm.
基金This project is supported by National Natural Science Foundation of China (No.50205006).
文摘An improved arc discharge method is developed to fabricate carbon nanotube probe of atomic force microscopy (AFM) here. First, silicon probe and carbon nanotube are manipulated under an optical microscope by two high precision microtranslators. When silicon probe and carbon nanotube are very close, several tens voltage is applied between them. And carbon nanotube is divided and attached to the end of silicon probe, which mainly due to the arc welding function. Comparing with the arc discharge method before, the new method here needs no coat silicon probe with metal film in advance, which can greatly reduce the fabrication's difficulty. The fabricated carbon nanotube probe shows good property of higher aspect ratio and can more accurately reflect the true topography of silicon grating than silicon probe. Under the same image drive force, carbon nanotube probe had less indentation depth on soft triblock copolymer sample than silicon probe. This showed that carbon nanotube probe has lower spring constant and less damage to the scan sample than silicon probe.
文摘The organization of the higher order structure of chromatin in chicken erythrocytes has been examined withtapping-mode scanning force microscopy under conditionsclose to their native environment. Reproducible highresolution AFM images of chromatin compaction at several levels can be demonstrated. An extended beads-on-astring (width of ~ 15-20nm, height of ~ 2-3nm for eachindividual nucleosome) can be consistently observed. Furthermore, superbeads (width of ~ 40nm, height of ~ 7nm)are demonstrated. Visualization of the solenoid conformation at the level of 30nm chromatin fiber is attained eitherby using AFM or by using electron microscopy. In addition, tightly coiled chromatin fibers (~ 50-60nm and ~90-110nm) can be revealed. Our data suggest that the chromatin in the interphase nucleus of chicken erythrocyte represents a high-order conformation and AFM provides useful high-resolution structural information concerning thefolding pattern of interphase chromatin fibers.
基金Supported by the National Key Research and Development Program of China(2018YFB2200500)the National Natural Science Foundation of China(51402230,51177134,21503153)+1 种基金Natural Science Basic Research Plan in Shaanxi Province of China(2017JM6075,2015JM6282)Scientific Research Program Funded by Shaanxi Provincial Education Department(17JK0335)。
文摘Si/SiC heterostructures with different growth temperatures were prepared on 6 HSiC(0001)by LPCVD.Current mode atomic force microscopy and transmission electron microscopy were employed to investigate the electrical properties and crystalline structure of Si/SiC heterostructures.Face-centered cubic(FCC)on hexagonal close-packing(HCP)epitaxy of the Si(111)/SiC(0001)heterostructure was realized at 900°C.As the growth temperature increases to1050°C,the<110>preferred orientation of the Si film is observed.The Si films on 6 H-SiC(0001)with different growth orientations consist of different distinctive crystalline grains:quasi-spherical grains with a general size of 20μm,and columnar grains with a typical size of 7μm×20μm.The electrical properties are greatly influenced by the grain structures.The Si film with<110>orientation on SiC(0001)consists of columnar grains,which is more suitable for the fabrication of Si/SiC devices due to its low current fluctuation and relatively uniform current distribution.
基金supported by the National Key R&D Program(No.2023YFB3709900)the National Nature Science Foundation of China(No.U22A20171)+2 种基金China Baowu Low Carbon Metallurgy Innovation Foundation(No.BWLCF202315)the High Steel Center(HSC)at North China University of TechnologyUniversity of Science and Technology Beijing,China.
文摘The characteristics of nonmetallic inclusions formed during steel production have a significant influence on steel performance.In this paper,studies on inclusions using confocal scanning laser microscopy(CSLM)are reviewed and summarized,particularly the col-lision of various inclusions,dissolution of inclusions in liquid slag,and reactions between inclusions and steel.Solid inclusions exhibited a high collision tendency,whereas pure liquid inclusions exhibited minimal collisions because of the small attraction force induced by their<90°contact angle with molten steel.The collision of complex inclusions in molten steel was not included in the scope of this study and should be evaluated in future studies.Higher CaO/Al_(2)O_(3)and CaO/SiO_(2)ratios in liquid slag promoted the dissolution of Al_(2)O_(3)-based in-clusions.The formation of solid phases in the slag should be prevented to improve dissolution of inclusions.To accurately simulate the dissolution of inclusions in liquid slag,in-situ observation of the dissolution of inclusions at the steel-slag interface is necessary.Using a combination of CSLM and scanning electron microscopy-energy dispersive spectroscopy,the composition and morphological evolution of the inclusions during their modification by the dissolved elements in steel were observed and analyzed.Although the in-situ observa-tion of MnS and TiN precipitations has been widely studied,the in-situ observation of the evolution of oxide inclusions in steel during so-lidification and heating processes has rarely been reported.The effects of temperature,heating and cooling rates,and inclusion character-istics on the formation of acicular ferrites(AFs)have been widely studied.At a cooling rate of 3-5 K/s,the order of AF growth rate in-duced by different inclusions,as reported in literature,is Ti-O<Ti-Ca-Zr-Al-O<Mg-O<Ti-Zr-Al-O<Mn-Ti-Al-O<Ti-Al-O<Zr-Ti-Al-O.Further comprehensive experiments are required to investigate the quantitative relationship between the formation of AFs and inclusions.
基金supported by the Project of Health Committee of Hunan Province(D202304128868),China.
文摘Objective:Verrucous epidermal nevus(VEN),seborrheic keratosis(SK),verruca plana(VP),verruca vulgaris(VV),and nevus sebaceous(NS)are common verrucous proliferative skin diseases with similar clinical appearances,often posing diagnostic challenges.Dermoscopy and reflectance confocal microscopy(RCM)can aid in their differentiation,yet their specific features under these tools have not been systematically described.This study aims to summarize and analyze the dermoscopic and RCM features of VEN,SK,VP,VV,and NS.Methods:A total of 121 patients with histopathologically confirmed verrucous proliferative skin diseases were enrolled.Dermoscopy and RCM imaging was used to observe and analyze the microscopic features of these conditions.Results:Under dermoscopy,the 5 diseases displayed distinct characteristics:VEN typically showed gyriform structures;SK was characterized by gyriform structures,comedo-like openings,and milia-like cysts;VP and VV featured dotted vessels and frogspawn-like structures;NS presented as brownish-yellow globules.RCM revealed shared features such as hyperkeratosis and acanthosis across all 5 diseases.Specific features included gyriform structures and elongated rete ridges in VEN;pseudocysts and gyriform structures in SK;evenly distributed ring-like structures in VP;vacuolated cells and papillomatous proliferation in VV;and frogspawn-like structures in NS.Conclusion:These 5 verrucous proliferative skin conditions exhibit distinguishable features under both dermoscopy and RCM.The combination of these 2 noninvasive imaging modalities holds significant clinical value for the differential diagnosis of verrucous proliferative skin diseases.
基金supported by the National Key Research and Development Program of China(Grant Nos.2022YFA1403300 and 2019YFA0308404)the National Natural Science Foundation of China(Grant Nos.11427902,11991060,12074075,12474165,12274084,and 12241402)+5 种基金Shanghai Municipal Science and Technology Major Project(Grant No.2019SHZDZX01)Shanghai Municipal Natural Science Foundation(Grant No.22ZR1407400)Innovation Program for Quantum Science and Technology(Grant No.2024ZD0300104)Innovation Program of Shanghai Municipal Education Commission(Grant No.2023ZKZD03)Science and Technology Commission of Shanghai Municipality(Grant No.20JC1415900)China Postdoctoral Science Foundation(Grant No.KLH1512149).
文摘Recently,charged solitons have been found in a two-dimensional CoCl_(2)/HOPG system,whose microscopic nature remains to be elusive.In this work,we investigate the charged solitons in monolayer CoCl_(2) using scanning tunneling microscopy(STM)and atomic force microscopy(AFM).Moreover,we study the electrical properties of the charged solitons at zero electric field by measuring local contact potential difference(LCPD)via Kelvin probe force microscopy(KPFM)using the Δf(V)method.The compensation voltage corresponding to the vertex of the parabola is obtained by fitting the quadratic relationship between Δf and sample bias.The results show that,without an external electric field,the solitons behave as negatively charged entities.Meanwhile,the LCPD mapping characterizes the spatial distribution of the potential at the charged solitons,which agrees well with those obtained from STM band bending measurements.
基金supported by the National Natural Science Foundation of China(Grant Nos.12104500 and 82430062)the Key Research and Development Projects of Shaanxi Province(Grant No.2023-YBSF-263),the Shenzhen Engineering Research Centre(Grant No.XMHT20230115004)the Shenzhen Science and Technology Innovation Commission(Grant No.KCXFZ20201221173207022).
文摘Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution for high-throughput digital pathology,combining high resolution,large field of view,and extended depth of field(DOF).However,the full-color capabilities of FPM are hindered by coherent color artifacts and reduced computational efficiency,which significantly limits its practical applications.Color-transferbased FPM(CFPM)has emerged as a potential solution,theoretically reducing both acquisition and reconstruction threefold time.Yet,existing methods fall short of achieving the desired reconstruction speed and colorization quality.In this study,we report a generalized dual-color-space constrained model for FPM colorization.This model provides a mathematical framework for model-based FPM colorization,enabling a closed-form solution without the need for redundant iterative calculations.Our approach,termed generalized CFPM(gCFPM),achieves colorization within seconds for megapixel-scale images,delivering superior colorization quality in terms of both colorfulness and sharpness,along with an extended DOF.Both simulations and experiments demonstrate that gCFPM surpasses state-of-the-art methods across all evaluated criteria.Our work offers a robust and comprehensive workflow for high-throughput full-color pathological imaging using FPM platforms,laying a solid foundation for future advancements in methodology and engineering.
文摘In this work, we investigate the Co-Si reaction, the Co growth mode at room temperature, diffusion be- haviour as well as morphology evolution during annealing on both H-terminated and clean Si(001) and Si(111) sur- faces. From in-situ X-ray photoelectron spectroscopy (XPS) investigation, “Co-Si” reaction appears to occur on both H-terminated and clean surfaces at room temperature (RT) and the silicide crystallinity is improved upon annealing. Co growth mode on H-terminated Si surfaces occurs in a pseudo layer-by-layer manner while small close-packed is- land growth mode is observed on the clean Si surface. Upon annealing at different temperatures, Co atom concentra- tion decreases versus annealing time, which in part is attributed to Co atoms inward diffusion. The diffusion behav- iour on both types of surfaces demonstrates a similar trend. Morphology study using ex-situ atomic force microscopy (AFM) shows that the islands formed on Si(001) surface after annealing at 700 °C are elongated with growth direc- tions alternate between the two perpendicular [ 110 ] and [110] directions. Triangular islands are observed on Si (111) surface.
基金financial support from the National Natural Science Foundation of China(Grant No.61971201)。
文摘High-resolution transmission electron microscopy(HRTEM)promises rapid atomic-scale dynamic structure imaging.Yet,the precision limitations of aberration parameters and the challenge of eliminating aberrations in Cs-corrected transmission electron microscopy constrain resolution.A machine learning algorithm is developed to determine the aberration parameters with higher precision from small,lattice-periodic crystal images.The proposed algorithm is then validated with simulated HRTEM images of graphene and applied to the experimental images of a molybdenum disulfide(MoS_(2))monolayer with 25 variables(14 aberrations)resolved in wide ranges.Using these measured parameters,the phases of the exit-wave functions are reconstructed for each image in a focal series of MoS_(2)monolayers.The images were acquired due to the unexpected movement of the specimen holder.Four-dimensional data extraction reveals time-varying atomic structures and ripple.In particular,the atomic evolution of the sulfur-vacancy point and line defects,as well as the edge structure near the amorphous,is visualized as the resolution has been improved from about 1.75?to 0.9 A.This method can help salvage important transmission electron microscope images and is beneficial for the images obtained from electron microscopes with average stability.
基金supported by University of Macao,China,Nos.MYRG2022-00054-FHS and MYRG-GRG2023-00038-FHS-UMDF(to ZY)the Macao Science and Technology Development Fund,China,Nos.FDCT0048/2021/AGJ and FDCT0020/2019/AMJ and FDCT 0011/2018/A1(to ZY)Natural Science Foundation of Guangdong Province of China,No.EF017/FHS-YZ/2021/GDSTC(to ZY)。
文摘To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral cortex.However,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly age-related.In this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed laser.We observed the molding process in mice of different ages and presented age-dependent vascular embolism differentiation.Moreover,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a stroke.Our imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes.
基金funded by the National Natural Science Foundation of China(No.62305041)the Natural Science Foundation of Liaoning Province(No.2023-MS-103)。
文摘Stochastic optical reconstruction microscopy(STORM),as a typical technique of single-molecule localization microscopy(SMLM),has overcome the diffraction limit by randomly switching fluorophores between fluorescent and dark states,allowing for the precise localization of isolated emission patterns and the super-resolution reconstruction from millions of localized positions of single fluorophores.A critical factor influencing localization precision is the photo-switching behavior of fluorophores,which is affected by the imaging buffer.The imaging buffer typically comprises oxygen scavengers,photo-switching reagents,and refractive index regulators.Oxygen scavengers help prevent photobleaching,photo-switching reagents assist in facilitating the conversion of fluorophores,and refractive index regulators are used to adjust the refractive index of the solution.The synergistic interaction of these components promotes stable blinking of fluorophores,reduces irreversible photobleaching,and thereby ensures high-quality super-resolution imaging.This review provides a comprehensive overview of the essential compositions and functionalities of imaging buffers used in STORM,serving as a valuable resource for researchers seeking to select appropriate imaging buffers for their experiments.
基金financially supported by the National Science Foundation of China(No.12274011)。
文摘The photocatalytic activity of a photocatalyst is significantly influenced by its microstructure.Therefore,it is crucial to understand and characterize the microstructure.Transmission electron microscopy(TEM)has been an indispensable tool that provides direct visualization of the microstructure at the atomic level.Despite numerous reviews on photocatalytic processes,there has been a lack of comprehensive summaries that focus on the critical role of TEM in photocatalytic applications.This review aims to fill this gap by highlighting the significant contributions of TEM techniques in understanding key photocatalytic processes,including light absorption,charge separation and transfer,and surface reaction.In addition,this review discusses in-situ TEM techniques for observing photocatalytic reactions and explores the challenges and future perspectives related to the application of TEM in photocatalysis.
基金supports from the National Natural Science Foundation of China(Grant No.52474059,Grant No.52174046)are greatly acknowledged.
文摘Fine particle detachment and subsequent migration can lead to severe pore plugging and consequent permeability decline.Therefore,it is crucial to quantify the critical condition when fine particle detachment occurs.The frequently observed deviations or even contradictions between experimental results and theoretical predictions of fines detachment arise from an insufficient understanding of adhesion force that can be highly influenced by salinity and temperature.To clarify the intrinsic influence of salinity and temperature on fines detachment,adhesion forces between carboxyl microspheres and hydrophilic silica substrates in an aqueous medium were measured at various salinities and tempera-tures using atomic force microscopy(AFM).The AFM-measured adhesion force decreases with increasing salinity or temperature.Trends of mean measured adhesion forces with temperature and salinity were compared with the DLVO and XDLVO theories.DLVO theory captured the trend with temperature via the impact of temperature on electric double layer interactions,whereas XDLVO theory captured the observed trend with salinity via the impact of salinity on the repulsive hydration force.Our results highlight the significance of hydration force in accurately predicting the fate of fines in porous media.