MIDNet:Deblurring Network for Material Microstructure Images

Scanning electron microscopy(SEM)is a crucial tool in the field of materials science,providing valuable insightsinto the microstructural characteristics of materials.Unfortunately,SEM images often suffer from blurrinesscaused by improper hardware calibration or imaging automation errors,which present challenges in analyzingand interpretingmaterial characteristics.Consequently,rectifying the blurring of these images assumes paramountsignificance to enable subsequent analysis.To address this issue,we introduce a Material Images DeblurringNetwork(MIDNet)built upon the foundation of the Nonlinear Activation Free Network(NAFNet).MIDNetis meticulously tailored to address the blurring in images capturing the microstructure of materials.The keycontributions include enhancing the NAFNet architecture for better feature extraction and representation,integratinga novel soft attention mechanism to uncover important correlations between encoder and decoder,andintroducing newmulti-loss functions to improve training effectiveness and overallmodel performance.We conducta comprehensive set of experiments utilizing the material blurry dataset and compare them to several state-of-theartdeblurring methods.The experimental results demonstrate the applicability and effectiveness of MIDNet in thedomain of deblurring material microstructure images,with a PSNR(Peak Signal-to-Noise Ratio)reaching 35.26 dBand an SSIM(Structural Similarity)of 0.946.Our dataset is available at:https://github.com/woshigui/MIDNet.

Ultrasonic Computed Tomography Imaging Method of Concrete Materials Based on Simulated Annealing Genetic Algorithm

Stability and accuracy of the imaging results are still unmet practical demands for ultrasonic computed tomography(CT)of concrete material.To address these issues,a CT technique based on simulated annealing genetic algorithm(SAGA)is presented in this work.Firstly,a natural weight matrix with clear physical meaning is introduced in the inverse algorithm and then a quadric broadening objective function is formed according to the propagation characteristics of ultrasound in concrete.After that,the simulated annealing(SA)searching is added to speed up the inverse process and to improve the convergence and stability of the algorithm.Finally,the optimal inverse imaging results have been achieved by variable ectopic adaptive genetic algorithm.The numerical simulation experiments have shown that the usage of the correct priori information and the excellent characteristic of SAGA in searching the global minimum value of the function have produced accurate and effective results with stable numerical values.The imaging resolution is improved and the imagining results reflecting the inner defections of the tested objects are more reliable and accurate.

Perspective on the imaging device based on perovskite materials

Large light absorption coefficients,tunable bandgaps,high tolerance to defects,long carrier lifetimes as well as diffusion lengths render lead halide perovskite materials ideal candidates for optoelectronic devices.Except application in solar cell,photodetectors based on perovskite materials have been recognized as another game changer due to the achievements such as high responsivity of 1.9×104 A/W[1],gain factor larger than 5.0×104[1],large detectivity of 1014 J[2],high on/off ratio of 105[3],fastest response time down to 1 ns[4],large linear dynamic range exceeding 170[5]and low detachable light intensity as small as 1 pW/cm2[6],which demonstrate the potential applications of perovskite based photodetector in the areas of weak light detection.

Applications of Secondary Electron Composition Contrast Imaging Method in Microstructure Studies on Heterojunction Semiconductor Devices and Multilayer Materials

The principle, imaging condition and experimental method for obtaining high resolution composition contrast in secondary electron image were described. A new technique of specimen preparation for secondary electron composition contrast observation was introduced and discussed. By using multilayer P+Si1-xGex/pSi heterojunction internal photoemission infrared detector as an example, the applications of secondary electron composition contrast imaging in microstructure studies on heterojunction semiconducting materials and devices were stated. The characteristics of the image were compared with the ordinary transmission electron diffraction contrast image. The prospects of applications of the imaging method in heterojunction semiconductor devices and multilayer materials are also discussed.

Coverless Information Hiding Based on the Molecular Structure Images of Material

The traditional information hiding methods embed the secret information by modifying the carrier,which will inevitably leave traces of modification on the carrier.In this way,it is hard to resist the detection of steganalysis algorithm.To address this problem,the concept of coverless information hiding was proposed.Coverless information hiding can effectively resist steganalysis algorithm,since it uses unmodified natural stego-carriers to represent and convey confidential information.However,the state-of-the-arts method has a low hidden capacity,which makes it less appealing.Because the pixel values of different regions of the molecular structure images of material(MSIM)are usually different,this paper proposes a novel coverless information hiding method based on MSIM,which utilizes the average value of sub-image’s pixels to represent the secret information,according to the mapping between pixel value intervals and secret information.In addition,we employ a pseudo-random label sequence that is used to determine the position of sub-images to improve the security of the method.And the histogram of the Bag of words model(BOW)is used to determine the number of subimages in the image that convey secret information.Moreover,to improve the retrieval efficiency,we built a multi-level inverted index structure.Furthermore,the proposed method can also be used for other natural images.Compared with the state-of-the-arts,experimental results and analysis manifest that our method has better performance in anti-steganalysis,security and capacity.

Cryogenic transmission electron microscopy on beam-sensitive materials and quantum science

Transmission electron microscopy(TEM)offers unparalleled atomic-resolution imaging of complex materials and heterogeneous structures.However,high-energy imaging electrons can induce structural damage,posing a challenge for electron-beam-sensitive materials.Cryogenic TEM(Cryo-TEM)has revolutionized structural biology,enabling the visualization of biomolecules in their near-native states at unprecedented detail.The low electron dose imaging and stable cryogenic environment in Cryo-TEM are now being harnessed for the investigation of electron-beam-sensitive materials and low-temperature quantum phenomena.Here,we present a systematic review of the interaction mechanisms between imaging electrons and atomic structures,illustrating the electron beam-induced damage and the mitigating role of Cryo-TEM.This review then explores the advancements in low-dose Cryo-TEM imaging for elucidating the structures of organic-based materials.Furthermore,we showcase the application of Cryo-TEM in the study of strongly correlated quantum materials,including the detection of charge order and novel topological spin textures.Finally,we discuss the future prospects of Cryo-TEM,emphasizing its transformative potential in unraveling the complexities of materials and phenomena across diverse scientific disciplines.

Enhancement of Biomass Material Characterization Images Using an Improved U-Net

For scanning electronmicroscopes with high resolution and a strong electric field,biomass materials under observation are prone to radiation damage from the electron beam.This results in blurred or non-viable images,which affect further observation of material microscopic morphology and characterization.Restoring blurred images to their original sharpness is still a challenging problem in image processing.Traditionalmethods can’t effectively separate image context dependency and texture information,affect the effect of image enhancement and deblurring,and are prone to gradient disappearance during model training,resulting in great difficulty in model training.In this paper,we propose the use of an improvedU-Net(U-shapedConvolutional Neural Network)to achieve image enhancement for biomass material characterization and restore blurred images to their original sharpness.The main work is as follows:use of depthwise separable convolution instead of standard convolution in U-Net to reduce model computation effort and parameters;embedding wavelet transform into the U-Net structure to separate image context and texture information,thereby improving image reconstruction quality;using dense multi-receptive field channel modules to extract image detail information,thereby better transmitting the image features and network gradients,and reduce the difficulty of training.The experiments show that the improved U-Net model proposed in this paper is suitable and effective for enhanced deblurring of biomass material characterization images.The PSNR(Peak Signal-to-noise Ratio)and SSIM(Structural Similarity)are enhanced as well.

Performance Assessment on Corrosion Resistance of Refractory Materials Based on High-temperature Machine Vision Technology

Refractory materials,as the crucial foundational materials in high-temperature industrial processes such as metallurgy and construction,are inevitably subjected to corrosion and penetration from high-temperature media during their service.Traditionally,observing the in-situ degradation process of refractory materials in complex high-temperature environments has presented challenges.Post-corrosion analysis are commonly employed to assess the slag resistance of refractory materials and understand the corrosion mechanisms.However,these methods often lack information on the process under the conditions of thermal-chemical-mechanical coupling,leading to potential biases in the analysis results.In this work,we developed a non-contact high-temperature machine vision technology by the integrating Digital Image Correlation(DIC)with a high-temperature visualization system to explore the corrosion behavior of Al2O3-SiO2 refractories against molten glass and Al2O3-MgO dry ramming refractories against molten slag at different temperatures.This technology enables realtime monitoring of the 2D or 3D overall strain and average strain curves of the refractory materials and provides continuous feedback on the progressive corrosion of the materials under the coupling conditions of thermal,chemical,and mechanical factors.Therefore,it is an innovative approach for evaluating the service behavior and performance of refractory materials,and is expected to promote the digitization and intelligence of the refractory industry,contributing to the optimization and upgrading of product performance.

FFT IMAGE APPLICATION TO DETECTION AND ANALYSIS OF THE DEFECTS IN GaAs MATERIALS

The presence of inhomogeneous distribution of defects in GaAs wafers strongly limits thereproductivity of IC fabrication processes.In this paper,we report for the first time a Fourier Transforma-tion Image Testing approach,called FTIT,for the two dimensional evaluation of the disorder in a wafer,asit appears in infrared transmission images.The fourier analysis of the cell struchture reveals a dominant statis-tical rectangular organization of the dislocations along【110】and【010】directions.The definitionsof α and β in the paper are typical of the organization of the cells to evaluate quantitatively properties ofIC materials.

Magnetic resonance imaging of the cirrhotic liver in the eraof gadoxetic acid

Gadoxetic acid improves detection and characterization of focal liver lesions in cirrhotic patients and can estimate liver function in patients undergoing liver resection.The purpose of this article is to describe the optimal gadoxetic acid study protocol for the liver,the unique characteristics of gadoxetic acid,the differences between gadoxetic acid and extra-cellular gadolium chelates,and the differences in phases of enhancement between cirrhotic and normal liver using gadoxetic acid.We also discuss how to obtain and recognize an adequate hepatobiliary phase.

Gadoxetic acid magnetic-enhanced resonance imaging in the diagnosis of cholangiocarcinoma

The use of liver magnetic resonance imaging is increasing thanks to itsmultiparametric sequences that allow a better tissue characterization, and the useof hepatobiliary contrast agents. This review aims to evaluate gadoxetic acidenhanced magnetic resonance imaging in the diagnosis and staging ofcholangiocarcinoma and its different clinical and radiological classificationsproposed in the literature. We also analyze the epidemiology, risk factors incorrelation with clinical findings and laboratory data.

Learning material law from displacement fields by artificial neural network

The recently developed data-driven approach can establish the material law for nonlinear elastic composite materials(especially newly developed materials)by the generated stress-strain data under different loading paths(Computational Mechanics,2019).Generally,the displacement(or strain)fields can be obtained relatively easier using digital image correlation(DIC)technique experimentally,but the stress field is hard to be measured.This situation limits the applicability of the proposed data-driven approach.In this paper,a method based on artificial neural network(ANN)to identify stress fields and further obtain the material law of nonlinear elastic materials is presented,which can make the proposed data-driven approach more practical.A numerical example is given to prove the validity of the method.The limitations of the proposed approach are also discussed.

3D visualization of the material flow in friction stir welding process

The material flow in friction stir welded 2014 Al alloy has been investigated using a marker insert technique （MIT）. Results of the flow visualization show that the material flow is asymmetrical during the friction stir welding （FSW） process and there are also significant differences in the flow patterns observed on advancing side and retreating side. On advancing side, some material transport forward and some move backward, but on retreating side, material only transport backward. At the top surface of the weld, significant material transport forward due to the action of the rotating tool shoulder. Combining the data from all the markers, a three-dituensional flow visualization, similar to the 3D image reconstruction technique, was obtained. The three-dimensional plot gives the tendency chart of material flow in friction stir welding process and from the plot it can be seen that there is a vertical, circular motion around the longitudinal axis of the weld. On the advancing side of the weld, the material is pushed downward but on the retreating side, the material is pushed toward the crown of the weld. The net result of the two relative motions in both side of the advancing and the retreating is that a circular motion comes into being. Comparatively, the material flow around the longitudinal axis is a secondary motion.

Field Sensing Characteristic Research of Carbon Fiber Smart Material

In order to research the field sensing characteristic of the carbon fiber smart material, the Tikhonov regularization principle and the modified Newton-Raphson(MNR) algorithm were adopted to solve the inverse problem of the electrical resistance tomography(ERT). An ERT system of carbon fiber smart material was developed. Field sensing characteristic was researched with the experiment. The experimental results show that the specific resistance distribution of carbon fiber smart material is highly consistent with the distribution of structural strain. High resistance zone responds to high strain area, and the specific resistance distribution of carbon fiber smart material reflects the distribution of sample strain in covering area. Monitoring by carbon fiber smart material on complicated strain status in sample field domain is realized through theoretical and experimental study.

Cooling and Crack Suppression of Bone Material Drilling Based on Microtextured Bit Modeled on Dung Beetle

In recent years,the number of patients with orthopedic diseases such as cervical spondylosis has increased,resulting in an increase in the demand for orthopedic surgery.However,thermal necrosis and bone cracks caused by surgery severely restrict the development and progression of orthopedic surgery.For the material of cutting tool processing bone in bone surgery of drilling high temperature lead to cell death,easy to produce the problem such as crack cause secondary damage effects to restore,in this paper,a bionic drill was designed based on the micro-structure of the dung beetle's head and back.The microstructure configuration parameters were optimized by numerical analysis,and making use of the optical fiber laser marking machine preparation of bionic bit;through drilling test,the mathematical model of drilling temperature and crack generation based on micro-structure characteristic parameters was established by infrared thermal imaging technology and acoustic emission signal technology,and the cooling mechanism and crack suppression strategy were studied.The experimental results show that when the speed is 60 m/min,the cooling effects of the bionic bit T1 and T2 are 15.31%and 19.78%,respectively,and both kinds of bits show obvious crack suppression effect.The research in this paper provides a new idea for precision and efficient machining of bone materials,and the research results will help to improve the design and manufacturing technology and theoretical research level in the field of bone drilling tools.

Imaging the crystal orientation of 2D transition metal dichalcogenides using polarization-resolved second-harmonic generation

We use laser-scanning nonlinear imaging microscopy in atomically thin transition metal dichalcogenides(TMDs)to reveal information on the crystalline orientation distribution,within the 2D lattice.In particular,we perform polarization-resolved second-harmonic generation(PSHG)imaging in a stationary,raster-scanned chemical vapor deposition(CVD)-grown WS2 flake,in order to obtain with high precision a spatially resolved map of the orientation of its main crystallographic axis(armchair orientation).By fitting the experimental PSHG images of sub-micron resolution into a generalized nonlinear model,we are able to determine the armchair orientation for every pixel of the image of the 2D material,with further improved resolution.This pixel-wise mapping of the armchair orientation of 2D WS2 allows us to distinguish between different domains,reveal fine structure,and estimate the crystal orientation variability,which can be used as a unique crystal quality marker over large areas.The necessity and superiority of a polarization-resolved analysis over intensity-only measurements is experimentally demonstrated,while the advantages of PSHG over other techniques are analysed and discussed.

Quantitative analysis of microstructure of carbon materials by HRTEM

The main object of the present research is to make a quantitative evaluation on the microstructure of carbon materials in terms of microcrystal. The digitized images acquired from finely pulverized carbon materials under HRTEM at a high magnification were processed by the image processing software so as to extract the fringes of (002) lattice of graphite crystal from the background image, and an FFT-IFFT filtering operation was performed followed by processes as binarization for the image and skeletonization for the fringes. A set of geometrical parameters including position, length and orientation was set up for every lattice fringe by calculating the binarized image. Then, the above obtained fringe parameters were put into an algorithm, which was especially developed for such fringe images so as to find fringes that could be regarded as those belonged to one single graphite microcrystal. The fringe was subjected sequentially to comparing procedures with every other fringe on aspects as parallelism, relative position and spacing, and the above comparisons were repeated till the last fringe. Eventually, the microcrystal size, its stacking number, and the distribution of the microcrystal in the whole sample, as well as other related structure information of such microcrystal in carbon materials were statistically calculated. Such microstructure information at nanometer level may contribute greatly to the interpretation of the properties of carbon materials and a better correlation with the same macrostructure.

Quantitative Analysis of Micro-porosity of Eco-material by Using SEM Technique

Microstructure of the eco-material combining vegetation recovery with slope protection is important for determining plant-growing properties.Several techniques for analyzing the eco-material microstructure are presented,including the freeze-cut-drying method of preparing samples for scanning electronic microscopy (SEM),the SEM image processing technique and quantifying analysis method of the SEM images,and etc.The aggregates and pores in SEM images are identified using the different mathematics operators,and their effects are compared.The areas of aggregates and pores are obtained using the operator of morphology,and the influences of different thresholds in image segmentation are also discussed.The results show that the method,in which the variation of non-maximum grey-level gradient is limited,improves the effect of edge detections due to a weak distinction existing at the edge between the aggregates and pores in image.The determination of the threshold should combine the image characteristic with filling operation,so as to assure the precision of the image analysis,in which the contact-segmentation is the simplest and most effective method.The results also show that the pore areas in eco-materials are generally larger than those in the correlative soils,and their increment is large as soil fabric being fine.These differences are related to admixture of expansive perlitic.The operator of morphology provides a new method for the image analysis of other porous material microstructure such as soils and concretes.

ON THE ELECTROELASTIC INTERACTION OF A PIEZOELECTRIC SCREW DISLOCATION WITH AN ELLIPTICAL INCLUSION IN PIEZOELECTRIC MATERIALS

The electroelastic interaction of a piezoelectric screw dislocation with an elliptical inclusion in piezoelectric materials is considered. The electroelastic fields in both the matrix and the inclusion were given explicitly by using the perturbation concept and the method of Laurent series expansion. Furthermore, the expressions of the image force acting on a piezoelectric screw disolcation were obtained. Numerical examples are provided to reveal the effect of piezoelectricity and the relative stiffness between the inclusion and the matrix on the image force. Consequently, the new interaction mechanism is found.

Design of small-scale gradient coils in magnetic resonance imaging by using the topology optimization method

A topology optimization method based on the solid isotropic material with penalization interpolation scheme is utilized for designing gradient coils for use in magnetic resonance microscopy.Unlike the popular stream function method,the proposed method has design variables that are the distribution of conductive material.A voltage-driven transverse gradient coil is proposed to be used as micro-scale magnetic resonance imaging(MRI)gradient coils,thus avoiding introducing a coil-winding pattern and simplifying the coil configuration.The proposed method avoids post-processing errors that occur when the continuous current density is approximated by discrete wires in the stream function approach.The feasibility and accuracy of the method are verified through designing the z-gradient and y-gradient coils on a cylindrical surface.Numerical design results show that the proposed method can provide a new coil layout in a compact design space.