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• A binary step-response serial coded target (BSSCT) is proposed, the binary step period in the image has a strong robustness to external noise interference, and the capacity can be greatly expanded by periodically encoding corner elements of coded targets. • A robust decoding algorithm based on multi-radius neighborhood search is proposed, the robust decoding of the dot-dispersing coded target using cross-ratio invariance needs to ensure P2-invariant stability. • The BSSCT coding and decoding method based on step period has a high recognition rate and location accuracy with different illumination environments, noise environments, and measurement angles. In close-range photogrammetry, it is difficult to meet the measurement requirements of large scenes in actual engineering due to the limited capacity of coded targets. To expand the capacity of the coded target, we propose a binary step-response serial-coded target (BSSCT). The BSSCT introduces periodic binary wave information as an additional feature in the dot-dispersing coded target. Also, a robust recognition algorithm for the BSSCT is developed, the P2-Invariant, and the step period is used for decoding. The capacity of the coded target reaches 7 magnitudes without increasing the auxiliary points. Under different lighting conditions and viewing angles, the measurement experiments show that the BSSCT outperforms other state-of-the-art coded targets. Our BSSCT is a promising standard method for large-field system calibration and object measurement. [ABSTRACT FROM AUTHOR]

We tested the hypothesis that chronic fetal hypoxia, at a severity present in many types of congenital heart disease, would lead to abnormal neurodevelopment. Eight mid-gestation fetal sheep were cannulated onto a pumpless extracorporeal oxygenator via the umbilical vessels and supported in a fluid-filled environment for 22 ± 2 days under normoxic or hypoxic conditions. Total parenteral nutrition was provided. Control fetuses (n = 7) were harvested at gestational age 133 ± 4 days. At necropsy, brains were fixed for histopathology. Neurons were quantified in white matter tracts, and the thickness of the external granular layer of the cerebellum was measured to assess neuronal migration. Capillary density and myelination were quantified in white matter. Data were analyzed with unpaired Student t tests or 1-way analysis of variance, as appropriate. Oxygen delivery was reduced in hypoxic fetuses (15.6 ± 1.8 mL/kg/min vs 24.3 ± 2.3 mL/kg/min, P <.01), but umbilical blood flow and caloric delivery were not different between the 2 groups. Compared with normoxic and control animals, hypoxic fetuses had reduced neuronal density and increased external granular layer thickness. Compared with normoxic and control animals, hypoxic fetuses had increased capillary density in white matter. Cortical myelin integrity score was lower in the hypoxic group compared with normoxic and control animals. There was a significant negative correlation between myelin integrity and capillary density. Chronic fetal hypoxia leads to white matter hyper-vascularity, decreased neuronal density, and impaired myelination, similar to the neuropathologic findings observed in children with congenital heart disease. These findings support the hypothesis that fetal hypoxia, even in the setting of normal caloric delivery, impairs neurodevelopment. [ABSTRACT FROM AUTHOR]

This work presents a new technique for 3D shape measurement of moving object in translational motion, which finds applications in online inspection, quality control, etc. A low-complexity 1D fast Fourier transform (FFT)-based spatial matching approach is devised to obtain accurate object displacement estimates, and it is combined with single shot fringe pattern prolometry (FPP) techniques to achieve high measurement performance with multiple captured images through coherent combining. The proposed technique overcomes some limitations of existing ones. Specifically, the placement of marks on object surface and synchronization between projector and camera are not needed, the velocity of the moving object is not required to be constant, and there is no restriction on the movement trajectory. Both simulation and experimental results demonstrate the effectiveness of the proposed technique. [ABSTRACT FROM AUTHOR]

A facile route has been established for the synthesis of PVP/CaF2: RE3+ and PVP/CaF2: Ce3+ nanoparticles (RE=Eu, Tb, Ce/Tb; PVP=Poly(N-vinyl-2-pyrrolidone)) heated at 70°C in ethanol at ambient pressure. The as-prepared nanoparticles were shown to be well dispersed in water. The nanoparticles were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The investigation of fluorescence properties showed that there exists energy transfer from the surface coating of PVP to Eu3+ and Tb3+ leading to the sensitized fluorescence emission of Eu3+ and Tb3+. Co-doping the PVP/CaF2: Tb3+ nanoparticles with Ce3+ results in significant increase in the emission intensity of Tb3+ and this has been attributed to the sensitization of Ce3+ and PVP on Tb3+. [ABSTRACT FROM AUTHOR]

Abstract: We systematically investigated the size-selective effects of geometrical structures and electronic properties on anionic (n =1–13) nanoclusters by using density functional theory (DFT-B3LYP) calculations with double-ξ LanL2DZ basis set. The lowest-energy structures and their low-lying isomers were identified. Compared with the neutral clusters, the ground state structures of and were obviously rearranged due to the addition of an extra electron. The threshold number of endohedral cage-like clusters was favored at n =10, whereas the most stable cluster was found at n =12, and reflected by the average binding energies and second-order difference in the total energies. The present results demonstrated that the induced effects by an additional electron to the neutral clusters can enhance their stabilities. However, the values of HOMO–LUMO gaps have a decreasing tendency along with the increasing number of Ge atoms. Adiabatic electron affinity (AEA), vertical electron affinity (VEA), and vertical detachment energy (VDE) were obtained and discussed in detail. The chemical bondings of some stable nanoclusters were also analyzed with the electron localization function (ELF). [Copyright &y& Elsevier]

Abstract: Phase Shift Profilometry (PSP) method is widely used in 3D shape measurement. The advantage of the PSP method is that it is less sensitive to the surface reflectivity variations and the object can be measured point by point. But if only a single wavelength λ 1 is used, the step height cannot be larger than λ 1/4. In order to measure step height object, Gray Code (GC) and Multi-Wavelength Phase Shift Profilometry (MWPSP) method are used. But the GC method cannot solve the problem of the objects with a variety of colors under different illumination. The shortcoming of MWPSP method is that its speed is too slow because a lot of images with multi-wavelengths should be captured by the system. In order to solve the problem of measurement speed and measurement range, a new phase unwrapping algorithm based on Three Wavelength Phase Shift Profilometry (TWPSP) is proposed in this paper. A series of fringe images only with three wavelengths λ 1, λ 2 and λ 3, are captured by the 3D measurement system. Three equivalent wavelengths λ 12, λ 23and λ 123 based on the original three wavelengths are calculated to perform the phase unwrapping algorithm. Compared with the GC method, the proposed method can measure the objects with different colors under different illuminations. Compared with the MWPSP method, the proposed method is faster and high precision. Experiments demonstrate that the proposed method is robust, high precision, low noise and suit to measure the object with variety colors under different illumination. It can be used to measure arbitrary step height and multiple objects together. [Copyright &y& Elsevier]

Abstract: Oleic acid (OA)-modified CaF2:Tb3+ nanoparticles with various Tb3+ concentrations and CaF2:Ce3+, Tb3+ nanoparticles were synthesized. The as-prepared nanoparticles were shown to be well dissolved in some common organic solvents, such as chloroform and toluene. The nanoparticles were characterized by Fourier transform infrared spectroscopy (FT-IR), X-Ray diffraction (XRD) and transmission electron microscopy (TEM). The investigation of fluorescence properties of CaF2:Tb3+ nanoparticles showed that the Tb3+ ions could be sensitized efficiently by the surface coating of OA and CaF2:Tb3+ nanoparticles with 10mol% Tb3+ concentrations possess the highest emission intensity. The comparison of emission for CaF2:Ce3+, Tb3+ and CaF2:Tb3+ (10mol%) nanoparticles revealed that the emission intensity of the former is about 4.5 times as strong as that of the latter. [Copyright &y& Elsevier]

Abstract: The title compound was firstly synthesized by solid state reaction and its single crystals were successfully obtained using a selected flux. It is isotypic with the mineral buetschliite, K2Ca(CO3)2, and crystallizes in the trigonal space group R-3m with a = 5.4526(12) Å, c = 17.781(8) Å, Z = 3. In the structure, Ba and K atoms are disordered on a same site in the proportion of 0.492(4):0.508(4). The fundamental building units are YO6 octahedra and BO3 triangles. The structure consists of [YB2O6]∞ double layers constructed by corner-sharing YO6 and BO3 groups. Ba/K atoms occupy the spaces between these two layers and play the role of bridges. In addition, the luminescence properties of Eu3+ doped KBaY(BO3)2 were also studied. [Copyright &y& Elsevier]

Abstract: The OA-modified CaF2: Eu nanocrystals that can be well dispersed in chloroform to form a clear solution were synthesized and characterized. The nanocrystals have a roughly spherical shape with particle diameter of about 10nm. Possible mechanism was proposed to explain the growth process. Upon the excitation at 395nm, the room-temperature emission spectrum of the nanocrystals in chloroform presents the characteristic transitions 5D0→7F J of Eu3+ ions, with 5D0→7F2 (610nm) transition as the most prominent group. The luminescence decay of Eu3+ ions in CaF2 nanocrystals was also investigated and two luminescence lifetimes of 737μs (11.2%) and 2.08ms (88.8%) were obtained. [Copyright &y& Elsevier]

Abstract: In this work, we have prepared a sol–gel derived hybrid material directly doped with Er1.4Yb0.6(Benzoate)6(Phen)2 (Phen=1,10-phenanthroline) complex, which was reported with intramolecular Yb–Er energy-transfer process in our previous work. The infrared (IR) spectra of the pure complex and hybrid gel material were investigated. The NIR photoluminescence (PL) spectrum of hybrid gel material shows strong characteristic emission of Er3+ with broad full width at half-maximum (FWHM) of 70nm. Judd–Ofelt theory was used in order to analyze the optical properties of Er3+ ions in the hybrid gel material. [Copyright &y& Elsevier]

3D surface measurement is an important requirement for modern industry. Non-contact optical method is a commonly used way to plot 2D and 3D measurement. Shape from shading (SFS) is a convenient 3D method because it can recover the 3D shape only from one image. But the existing SFS research has a lot of restriction, such as Lambertian illumination model. If the object is not under Lambertian model, the precision will decrease quickly. We propose an improved SFS based on BP neural network combining with genetic algorithm. This proposed SFS can provide the approximation of the reflectance model. So even the object is not under Lambertian light source, it can also be recovered and the precision has been greatly increased. It has been tested in the 3D reconstruction of synthetic vase, black and complex motorcar part, and really used in the online 3D measurement of work pieces. [Copyright &y& Elsevier]

Abstract: Automatic 3D surface reconstruction has been an important research topic in digital photogrammetry for many years. Shaping from stereoscopic information is one of the widely studied topics in computer vision. Its central part is to solve the stereo matching problem automatically. Most algorithms used to solve the matching problem can be categorized as either area-base techniques or feature-based techniques. Feature-based techniques have gained more and more popularity for and it is the method that supports activities in object recognition and image understanding. But none of the former research can ensure the 100% matching exactness, thus, cannot complete high precision 3D surface measurement. In order to improve the precision of 3D measurement, we design a novel grating matching method, which can ensure 100% matching accuracy. It does not need any other assistant symbol or flag, only select one of the gratings which have to be projected to the objects. On the beginning of the measurement, the background of the object is captured by a CCD camera. Later gratings include single grating and group gratings will be projected to the object in sequence. All the images include gratings will make a subtraction with the background. The difference of the two images will be treated as 3D cues to acquire the 3D shape. Because no recognizing work is needed, the location of the single grating and each one in the group can be positioned exactly. From a lot of experiments, the proposed grating matching method is proved and it is a technique with high precision, low costs, easy operation, and an automatically matching method. Furthermore, it can be widely used in most of 3D vision recovery systems. [Copyright &y& Elsevier]

Abstract: On the background of increasing request for stringent quality improvement and rising productivity, requirements for online measurement systems are growing as well. Among all the measurement tools, the vision system is considered as the most appropriate tool to provide proper accuracy, high speed, low cost, and 100% online inspection. Structure lighting sensor is the most popular method used in vision system. In this paper, the theory of vision system based on structure lighting is introduced. The measurement application to the seamless steel tube is introduced particularly. Another typical application, the online measurement on car body using structure lighting, is also illustrated. [Copyright &y& Elsevier]

Abstract: Sphericity evaluation is an important work in modern industry. Because the former 3D measurement is complex and with low precision, a lot of sphericity evaluation is studied only based on 2D measurement. But the 2D sphericity evaluation method is reported unreasonable because sphere is a 3D object. In order to evaluate sphericity error accurately and effectively, based on SFS-NDT 3D measurement method studied in reference [Research on 3D recovery based on only one online measuring image. TianJin University, Doctor thesis (2004)], this paper proposes a novel 3D sphericity evaluation method, which use all the 3D data in the evaluation procedure. Minimum zone solution using all the 3D data is adopted to make the evaluation more accurate and reliable. Compared with the conventional sphericity evaluation based on 2D measurement, the proposed 3D evaluation has the merits of non-contact, non-destructive, low cost, high speed, and high reliable. 3D shape recovery of a sphere based on SFS and its 3D sphericity evaluation procedure will be analyzed in this paper. [Copyright &y& Elsevier]

Abstract: NDT plays a crucial role in everyday life and is necessary to assure safety and reliability. NDT applied to surface detection as far as possible should be a non-contacting technique operating easily with low inspection costs and a high accuracy, human beings as inspectors as well as the environment should not be harmed. A novel NDT based on Shape From Shading (SFS) is introduced in this paper. SFS is a prospecting 3D recovery method because it recovers 3D shape of work piece only from one image. We firstly use SFS in the field of 3D surface defect detection, which is an effective way to guarantee the product quality. Compared with other defect detection method, this SFS method only needs CCD, optical system, image-collection card and computer. It has the merits such as low cost, easy operation, non-contact, non-destructive, no harming to people, and it is 3D overall shape detection. SFS-NDT has been used in the online defect detection measurement of TianJin SanHuan new material Ltd in Chinese Academy of Science. The 3D shape recovery method and application in the field of defect detection are presented. The precision of 3D recovery is analyzed. [Copyright &y& Elsevier]

Ferritin is the main iron storage protein and plays an important role in maintaining iron homeostasis. In a previous study, we reported that apoferritin exerted a neuroprotective effect against MPTP by regulation of brain iron metabolism and ferroptosis. However, the precise cellular mechanisms of extracellular ferritin underlying this protection are not fully elucidated. Ferritin was reported to be localized in different intracellular compartments, cytoplasm or released outside cells. Here we demonstrated that the intracellular iron increased after iron treatment in primary cultured astrocytes. These iron-loaded astrocytes released more ferritin in order to buffer extracellular iron. Using co-culture system of primary cultured astrocytes and MES23.5 dopaminergic cells, we showed that ferritin released by astrocytes could enter MES23.5 dopaminergic cells. And primary cultured astrocytes protected MES23.5 dopaminergic cells against 1-methyl-4-phenylpyridinium ion (MPP+)-induced neurotoxicity and ferroptosis. In addition, we found that exogenous Apoferritin or Ferritin pretreatment could significantly inhibit MPP+-induced cell damage by restoring the cell viability and mitochondrial transmembrane potential (ΔΨm). Furthermore, exogenous Apoferritin and Ferritin might also protect MES23.5 dopaminergic cells against MPP+ by decreasing reactive oxygen species (ROS) and inhibiting the increase of the labile iron pool (LIP). This suggests that astrocytes increased ferritin release to respond to iron overload, which might inhibit iron-mediated oxidative damage and ferroptosis of dopamine (DA) neurons in Parkinson's disease (PD). [Display omitted] • Astrocytes increased ferritin release to respond to iron overload. • Astrocytes protected MES23.5 dopaminergic cells against MPP +-induced neurotoxicity. • Exogenous Apoferritin or Ferritin protected against MPP +-induced cell damage. [ABSTRACT FROM AUTHOR]

In the industrial scenes, the machinery operates under diverse working conditions and generates varying levels of noise, which can hinder the performance of the intelligent fault diagnosis model that is trained in the laboratory. This is because the different working conditions and environmental noise change the distribution of laboratory vibration signal. To tackle this issue, we proposed a novel transfer soft thresholding network (TSoft-Net) based on self-attention for intelligent fault diagnosis of rotating machinery, which has good anti-noise performance and can be transferred to different working conditions with excellent accuracy. This paper constructs a soft residual block for extracting the fault representation and enhancing the residual learning. In this block, we propose a residual factor to learn and enhance domain-invariant fault representation. Furthermore, a representation soft fusion block is built for extracting and fusing the different scale fault representation. In this block, we propose a scale-attention weight to dynamically fuse the different scale fault representation. The experiments show that the TSoft-Net, compared with six existing methods on eight sub-datasets, has better anti-noise ability and achieves an accuracy of up to 100% on the target domain. • A soft residual block is constructed to extract the domain-invariant fault representation. • A representation soft fusion block is constructed to extract the fault representation at different scales. • The anti-noise and transfer performance of the TSoft-Net is verified. • We interpret the TSoft-Net validity from the perspective of the high-level features and gradient. [ABSTRACT FROM AUTHOR]

A new phosphate crystal CsMg 2 P 3 O 10 was grown by molten salt method. The single-crystal X-ray diffraction analysis reveals that this compound crystallizes in orthorhombic space group P bcn (No.60) with unit cell parameters a = 7.8757(8) Å, b = 8.6902(9) Å and c = 13.7235(14) Å, V = 939.26(17) Å3. In the structure, the basic building units are the [P 3 O 10 ]5- trimers consisted of three PO 4 tetrahedra shared the corner oxygen atoms, and the [Mg 2 O 8 ] dimers composed of two MgO 5 hexahedrons linked through edge-sharing. The structure exhibits a novel three-dimensional network, constructed by the [Mg 2 O 8 ] dimers and [P 3 O 10 ]5- trimers, where the Cs+ ions reside in the cavities. Furthermore, some related tests and first-principle calculations were employed for the compound characterization. Image 1087 • The crystals of CsMg 2 P 3 O 10 were successfully obtained using molten salt method. • The basic building units are the [P 3 O 10 ]5- trimer and [Mg 2 O 8 ] dimer in CsMg 2 P 3 O 10. • Polycrystalline samples of CsMg 2 P 3 O 10 can be easily synthesized by solid-state reaction method. [ABSTRACT FROM AUTHOR]

In arthropods, the large majority of studies on olfaction have been focused on insects, where most of the proteins involved have been identified. In particular, chemosensing in insects relies on two families of membrane receptors, olfactory/gustatory receptors (ORs/GRs) and ionotropic receptors (IRs), and two classes of soluble proteins, odorant-binding proteins (OBPs) and chemosensory proteins (CSPs). In other arthropods, such as ticks and mites, only IRs have been identified, while genes encoding for OBPs and CSPs are absent. A third class of soluble proteins, called Niemann-Pick C2 (NPC2) has been suggested as potential carrier for semiochemicals both in insects and other arthropods. Here we report the results of a proteomic analysis on olfactory organs (Haller's organ and palps) and control tissues of the tick Ixodes ricinus , and of immunostaining experiments targeting NPC2s. Adopting different extraction and proteomic approaches, we identified a large number of proteins, and highlighted those differentially expressed. None of the 13 NPC2s known for this species was found. On the other hand, using immunocytochemistry, we detected reaction against one NPC2 in the Haller's organ and palp sensilla. We hypothesized that the low concentration of such proteins in the tick's tissues could possibly explain the discrepant results. In ligand-binding assays the corresponding recombinant NPC2 showed good affinity to the fluorescent probe N-phenylnaphthylamine and to few organic compounds, supporting a putative role of NPC2s as odorant carriers. [ABSTRACT FROM AUTHOR]

A new halophosphate crystal Sr 3 P 3 O 10 Cl was grown in molten chloride flux media. It crystallizes in the centrosymmetric orthorhombic space group Pnma (No. 62) with a = 10.617(2) Å, b = 10.736(2) Å, and c = 8.7354(17) Å. In the structure, the basic building unit is the [P 3 O 10 ] 5− anion, which is consist of three PO 4 tetrahedra by sharing the corner oxygen atoms. The two Sr atoms and the Cl atom are linked to construct an infinite [Sr 3 Cl] 5+ chain. The [P 3 O 10 ] 5− anions are interconnected with the [Sr 3 Cl] 5+ chains to form a three-dimensional frameworks. Additionally, the first-principle calculation was employed to obtain the band structures and densities of states. [ABSTRACT FROM AUTHOR]

Perovskite compounds are always the focus in the material research field. Herein, the polycrystalline samples and single crystals of Na 2 ZrTeO 6 , a B-site ordered double-perovskite compound, were prepared successfully. Single crystal X-ray diffraction demonstrated that Na 2 ZrTeO 6 crystallizes in the cubic space group Fm-3m (No. 225) with unit parameters of a = b = c = 7.80360(10) Å. The crystal structure of Na 2 ZrTeO 6 , formed by ZrO 6 and TeO 6 octahedra through sharing the corner oxygen atoms, belongs to the typical rock-salt-type perovskite structure. The density functional theory calculations show that Na 2 ZrTeO 6 has a direct band gap with band gap of 3.21 eV, which is lower than the experimental value of 3.85 eV. Interestingly, the powder samples of Na 2 ZrTeO 6 exhibit a self-activated near-infrared emission centered at 780 nm under ultraviolet light excitation. And a strong luminescence thermal stability was also observed. Compared to room temperature, the luminescence intensity can maintain 64 % at 200 °C. [Display omitted] • The high-purity double-perovskite Na 2 ZrTeO 6 samples were synthesized by wet chemical method. • Structure analysis indicate that Na 2 ZrTeO 6 belongs to the typical rock-salt-type perovskite structure. • Na 2 ZrTeO 6 exhibits self-activated near-infrared emission centered at 780 nm excited by 308 nm. • The sample's emission intensity maintained 64 % of its room temperature peak intensity at 200 °C. [ABSTRACT FROM AUTHOR]

• A robust monitoring approach with dictionary pair learning is proposed to reduce the computation burden during model development. • An l 2 , 1 -norm constraint is enforced on the projective analytical dictionary to alleviate the negative effect of outliers. • A graph embedding regularizer is developed to preserve the comprehensive information of original data. • Fault diagnosis strategy in terms of reconstruction is introduced to identify fault variables. Process data collected from industrial processes is frequently corrupted with outliers, which arouses a challenge to monitor industrial processes. In this context, robustness to corruption is critical for an efficient process monitoring approach. In this paper, we propose a novel method termed as graph embedding dictionary pair learning (GEDPL) for robust process monitoring. The proposed method jointly learns a synthetic dictionary and an analytical dictionary for data representation, which reduces the computation burden during the training phase over the monitoring method based on traditional dictionary learning with the l 1 or l 0 -norm sparsity constraint. To alleviate the negative effect of corruption, an l 2 , 1 -norm constraint is forced on the projective analytical dictionary to enhance robustness of the dictionary. Moreover, a graph embedding regularizer is constructed to preserve local geometric information and global structures in data. In this way, the faithful reduced-dimensional representations can be effectively captured, improving the subsequent process monitoring capability. Besides, a reconstruction-based contribution plot based on the GEDPL is developed to identify fault variables. Finally, two case studies, including the Tennessee Eastman benchmark processes and a real-world industrial application, validate the efficacy of the proposed process monitoring scheme. [ABSTRACT FROM AUTHOR]

• In order to reconstruct the 3D bubble flow field quickly and accurately, a Bi-Direction Filtering Maximum Likelihood Expectation Maximization (BDF-MLEM) algorithm is proposed based on multi-view images. The BDF-MLEM algorithm improves the reconstruction accuracy and computation speed of 3D reconstruction for bubble flow field. • The main highlights of this work are as follows. • A multi-camera calibration method was proposed in this work. • A BDF-MLEM algorithm for 3Dreconstruction of bubble flow field is proposed. • The effectiveness of BDF-MLEM algorithm is verified by experiments. Aiming at the problem of the three-dimensional (3D) reconstruction of bubble flow field, a Bi-Direction Filtering Maximum Likelihood Expectation Maximization (BDF-MLEM) algorithm based on multi-view bubble images was proposed in this work. The calibration method for the multi-view was studied to unify the world coordinate systems and obtain the mapping relationship between the 3D world and the projection images. Combined with the calibration results, a 3D reconstruction algorithm of BDF-MLEM for bubble flow field was developed from MLEM. In BDF-MLEM, the setting method of iterative initial value was optimized and the projection and back projection methods in the iterative process was improved based on bi-direction filtering. The experimental results have shown that, compared with SART algorithm and MLEM algorithm, both the reconstruction speed and reconstruction accuracy of the proposed BDF-MLEM algorithm were greatly improved. In addition, the reconstruction results of overlapped bubbles have been improved to some extent by using the proposed method. [ABSTRACT FROM AUTHOR]

Structures, chemical stabilities and nonlinear optical properties of alkali metals-adsorbed niobium-doped silicon (M@Si n Nb + ) clusters are investigated using the DFT methods. The alkali metals prefer energetically to be attached as bridged bond rather than M–Si single bond in most of optimized structures. Adsorption of alkali metals on doped silicon clusters gradually enhances their chemical stabilities with increasing cluster size. Noteworthily, the first hyperpolarizabilities ( β tot ) of the M@Si n Nb + clusters, obtained by using the long-range corrected CAM-B3LYP functional, are large enough to establish their strong nonlinear optical behavior, especially for M@Si 9 Nb + (M = Li, Na, and K), and the enhanced β tot ordering by alkali metals is Na > K > Li. [ABSTRACT FROM AUTHOR]

Accuracy of machinery fault diagnosis and interpretability of diagnosis methods are fundamental to safe operation of machinery and help to improve the universality of the model. Mechanical vibration signals can reflect the operating state of the machine. Therefore, to improve the accuracy of fault diagnosis, this paper constructs a 6-layer residual neural network (ResNet06), which embeds two residual blocks to fully extract features of the mechanical vibration signals. Then, we use the gradient-based class activation map (Grad-CAM) and eigenvector-based class activation map (Eigen-CAM) to interpret the ResNet06 visually and to verify the ResNet06 correctness. Experimental results indicate that the fault diagnosis accuracy of our proposed model can reach almost 100%, and it can be seen that the model can accurately capture the fault points by the visualization of the model. • Based on features of vibration signals, we construct a 6-layer residual neural model. • Use the Grad-CAM and Eigen-CAM to interpret the ResNet06. • Visualize advanced features using t-SNE. Analyze the clustering of advanced features. [ABSTRACT FROM AUTHOR]