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Simiao Yong’an decoction (SMYAD), a classic traditional Chinese medicine formula, has been used to treat atherosclerosis (AS) in clinical in China, but its therapeutic mechanism and pharmacodynamic material basis are not clear. In this study, the AS model was caused by a high-fat diet and perivascular carotid collar placement (PCCP), and SMYAD was orally administered to the model and normal mice. A rapid, sensitive, selective, and reliable method using ultrahigh-performance liquid chromatography (UHPLC) system combined with a Q Exactive HF-X mass spectrometer (UHPLC-Q Exactive HF-X MS) was established and validated for the simultaneous determination of seven compounds, including harpagide, chlorogenic acid, swertiamarin, sweroside, angoroside C, liquiritin, and isoliquiritigenin in the plasma of normal and AS mice. The specificity, linearity, precision, accuracy, recovery, and stability of the method were all within the acceptable criteria. The results showed that some pharmacokinetic behaviors of harpagide, chlorogenic acid, and isoliquiritigenin were significantly different among the two groups of mice. The specific parameter changes were harpagide (AUC0–t and AUC0–∞ were 11075.09 ± 2132.38 and 16221.95 ± 5622.42 ng·mL−1·h, respectively; CLz/F was 2.45 ± 0.87 L/h/mg), chlorogenic acid (t1/2 was 21.59 ± 9.16 h; AUC0–∞ was 2637.51 ± 322.54 ng·mL−1·h; CLz/F was 13.49 ± 1.81 L/h/mg) and isoliquiritigenin (AUC0–t and AUC0–∞ were 502.25 ± 165.65 and 653.68 ± 251.34 ng·mL−1·h, respectively; CLz/F was 62.16 ± 23.35 L/h/mg) were altered under the pathological status of AS. These differences might be partly ascribed to the changes in gastrointestinal microbiota, nonspecific drug transporters, and cytochrome P450 activity under the AS state, providing research ideas and experimental basis for pharmacological effects and pharmacodynamic material basis.

LiNO

Six degree of freedom laser measurement technology has many advantages, such as high measurement accuracy, wide measurement area, non-contact measurement and so on. It is a powerful multi degree of freedom simultaneous measurement technology, and has very important applications in many fields, such as aerospace, precision manufacturing, weapons and equipment. This paper briefly introduces the main technology of six degree of freedom laser interferometry system, and summarizes the main measurement technology, including the measurement technology and method based on the combination of laser interference and laser collimation, the measurement technology and method based on laser grating interference, and the measurement technology and method based on laser tracking. This paper summarizes the research progress and development of six degree of freedom laser measurement technology in recent years, summarizes the role of six degree of freedom laser measurement technology in the main fields, and forecasts the future development trend of six degree of freedom laser interferometry technology.

Air refractive index measurement technology based on laser interference has shown great application value in many fields, especially in laser ranging, precision manufacturing and integrated circuit manufacturing equipment. With the help of air refractive index measurement technology, the measurement problems in many fields can be solved. In this paper, the research progress of indirect measurement method, synthetic pseudo wavelength method, F-P cavity method, variable cavity length method and optical frequency comb measurement method are introduced, and the advantages and disadvantages of various measurement methods are analyzed. Compared with the indirect measurement method, the direct measurement method based on laser interference technology has higher measurement accuracy. Finally, the current application status of air refractive index measurement technology is introduced, and its future application prospect and development trend are described in detail.

Atomistic simulations were employed to investigate the stress field spatial distributions, strain energy of the 1/2 〈1 1 1〉 {1 1 0} edge dislocation, and the binding energies between the edge dislocation and the point defects in tungsten, based on two different embedded-atom method (EAM) potentials. The basic static properties are consistent with the elastic theory of dislocations for these two potentials. Comparatively speaking, the map of the binding energy between the edge dislocation and the monovacancy illustrates that the results based on the Marinica’s potential fits better with the elastic theory. In addition, we obtained the radii of absorption between the point defects and the edge dislocation in the slip plane (the maximum value is 19 A for the monovacancy, while 34 A for the self-interstitial atom (SIA)) at 0 K. By calculating the binding energy and the interaction radii, we found the intensity of the interaction between the SIA and the edge dislocation is stronger than that of the vacancy and the edge dislocation.

In digital furniture design, skillful designers usually use professional software to create new furniture designs with various textures and then take advantage of rendering tools to produce eye-catching design results. Generally, a fine- grained furniture model holds many geometric details, inducing significant time cost to model rendering and large data size for storage that are not desired in application scenarios where efficiency is greatly emphasized. To accelerate the rendering process while keeping good rendering results as many as possible, we develop a novel decimation technique which not only reduces the number of faces on furniture models, but also retains their geometric and texture features. Two metrics are utilized in our approach to measure the distortion of texture features. Considering these two metrics as guidance for decimation, high texture distortion can be avoided in simplifying the geometric models. Therefore, we are able to build multi-level representations with different detail levels based on the initial design. Our experimental results show that the developed technique can achieve excellent visual effects on the decimated furniture model.

A novel method based on acoustic pulse-compression and envelope extraction is proposed and discussed to detect and locate hydrate blockage and leak in natural gas pipelines. Linear frequency modulation (LFM) signal rather than single frequency sinusoidal signal is emitted to inspect the pipeline. Reflected signal is firstly processed through a matched filter and then demodulated with Hilbert transform so that the envelope is obtained. By envelope subtraction, the detection and location of hydrate blockage and leak can be achieved. Based on the measurement and signal processing principle, a simulation model has been established with COMSOL which verifies the feasibility of the method. Experimental results demonstrate that the technique can not only locate hydrate blockage and pipeline leak precisely but also monitor the hydrate formation process in real time. Besides, the spatial resolution is improved and the interference of noises is reduced significantly thanks to matched filtering. The novel method has significantly enhanced the performance of existing system and has considerable application prospect in natural gas pipeline safety online monitoring.

Moral dilemma judgements frequently involve decisions where moral norms and the greater good are in conflict. The current preregistered study tested the effect of the steroid hormone testosterone on moral dilemma judgements using a double-blind administration of testosterone or placebo. Counter to predictions, testosterone administration led to increased inaction in moral dilemmas where harmful actions prohibited by moral norms increase overall well-being. Using a mathematical model to disentangle sensitivity to consequences, sensitivity to moral norms and general preference for inaction versus action, analyses further revealed that testosterone administration influenced judgements by increasing sensitivity to moral norms. Exploratory analyses suggested the opposite pattern for endogenous testosterone measured at baseline, in that higher levels of endogenous testosterone were associated with lower sensitivity to moral norms. The results indicate that the role of testosterone in moral judgements is more complex than suggested by previous findings. PROTOCOL REGISTRATION: The stage 1 protocol for this Registered Report was accepted in principle on 13 November 2017. The protocol, as accepted by the journal, can be found at https://osf.io/rysbe/ 1.

Fouling is inevitable in fluid-conveying pipes which can decrease flow rate, reduce thermal conductivity and increase energy consumption significantly, even cause industrial accidents. As there are some drawbacks in existing descaling methods, a new approach based on leaky guided ultrasonic waves cavitation is proposed in this paper, which is non-destructive and able to cut down downtime costs compared to the existing methods. This paper includes theoretical studies, finite element modeling work and a series of experiments. A frequency selection principle has been proposed to assure that the descaling process is non-destructive and uniform. The results show that this new approach is of high efficiency in descaling a water-filled pipe.

In this paper, an environmental and innovative clean technique for pipeline fouling is proposed, which is based on leaky ultrasonic guided waves (LUGWs) generated by quasi-axisymmetric excitation mode. The cavitation, which induced by the LUGWs in liquid medium, is employed for removing fouling inside a pipe. Cavitation corrosion and high-speed jet generated by the collapse of cavitation bubbles destroy fouling layer, and no by-products are formed during the removal process, which means that fouling removal in this way is friendly to the environment. The working frequency is determined by finite element method models and experiment. The effect of removal and its uniformity are measured by mass analysis, scanning electron microscope and energy-dispersive spectroscopy from macro to micro. The descaling experiment results show that the proposed method is able to remove the fouling inside a pipe uniformly.

The aging of the transformer oil-paper insulation distributes spatially, which results in changes in paper resistivity in different regions. This paper establishes an iterative inversion algorithm using the finite element method to calculate the oil-immersed paper resistivity in different regions of a transformer. This algorithm sets the transformer dielectric loss factor tan δ at low frequency, the dielectric parameters of the transformer oil as inputs and the oil-immersed paper resistivity as output. The resistivity obtained from inversion can be used as a reference to access the insulation state of the oil-paper insulation. This paper aims at achieving the nondestructive detection of the partial state of the oil-paper insulation.

As a promising pathway toward low-cost, long-duration energy storage, rechargeable sodium batteries are of increasing interest. Batteries that incorporate metallic sodium as anode promise a high theoretical specific capacity of 1166 mAh g

Lithium-sulfur (Li-S) batteries have been recognized as one of the most promising choices beyond lithium-ion batteries (LIB), because of its low cost and high theoretical specific energy (~2510 Wh/kg or ~10 times of LIB). However, Li-S batteries still face a few challenges, including large volume expansion, poor conductivity, low active material loading, inert end products, and polysulfide crossover called the “shuttle effect”, etc. To address these challenges, we have incorporated lithium iron phosphate (LFP) into our sulfur composite cathode. The addition of LFP enabled a more uniform slurry rheology, which allowed mass loading to double the amount of typical sulfur cathodes. Meanwhile, LFP can effectively adsorb polysulfides, which restricted the shuttle effects common in high-sulfur-loading batteries. Our LFP-hybrid Li-S batteries showed high areal capacity for 300 cycles under both low- and high-current charge-discharge cycles. More importantly, our characterizations demonstrated that LFP in Li-S batteries can reconstruct into Fe2P during cycling. We propose that Fe2P is an effective electrocatalyst for anchoring polysulfides. To unveil the role of Fe2P, we have directly incorporated these materials into the sulfur composite cathode. Using a hydrothermal synthesis, we showed that Fe2P nanoparticles can be directly anchored on the sulfur-carbon composite. This approach caused minimal phase separation and enabled a uniform morphology. We presented the analysis of the cathodes by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). These results allow us to develop a mechanistic hypothesis and a comparison between Fe2P and LFP in terms of the electrochemical performances.

A pressing need in low energy spintronics is two-dimensional (2D) ferromagnets with Curie temperature above the liquid-nitrogen temperature (77 K), and sizeable magnetic anisotropy. We studied Mn3Br8 monolayer which is obtained via inducing Mn vacancy at 1/4 population in MnBr2 monolayer. Such defective configuration is designed to change the coordination structure of the Mn-d5 and achieve ferromagnetism with sizeable magnetic anisotropy energy (MAE). Our calculations show that Mn3Br8 monolayer is a ferromagnetic (FM) half-metal with Curie temperature of 130 K, large MAE of − 2.33 meV per formula unit, and atomic magnetic moment of 13/3μB for the Mn atom. Additionally, Mn3Br8 monolayer maintains to be FM under small biaxial strain, whose Curie temperature under 5% compressive strain is 160 K. Additionally, both biaxial strain and carrier doping make the MAE increases, which mainly contributed by the magneto-crystalline anisotropy energy (MCE). Our designed defective structure of MnBr2 monolayer provides a simple but effective way to achieve ferromagnetism with large MAE in 2D materials.

Reversible electrodeposition of metals at liquid-solid interfaces is a requirement for long cycle life in rechargeable batteries that utilize metals as anodes. The process has been studied extensively from the perspective of the electrochemical transformations that impact reversibility, however, the fundamental challenges associated with maintaining morphological control when a intrinsically crystalline solid metal phase emerges from an electrolyte solution have been less studied, but provide important opportunities for progress. A crystal growth stabilization method to reshape the initial growth and orientation of crystalline metal electrodeposits is proposed here. The method takes advantage of polymer-salt complexes (PEG-Zn2+ -aX- ) (a = 1,2,3) formed spontaneously in aqueous electrolytes containing zinc (Zn2+ ) and halide (X- ) ions to regulate electro-crystallization of Zn. It is shown that when X = Iodine (I), the complexes facilitate electrodeposition of Zn in a hexagonal closest packed morphology with preferential orientation of the (002) plane parallel to the electrode surface. This facilitates exceptional morphological control of Zn electrodeposition at planar substrates and leads to high anode reversibility and unprecedented cycle life. Preliminary studies of the practical benefits of the approach are demonstrated in Zn-I2 full battery cells, designed in both coin cell and single-flow battery cell configurations.

The identification of the modulation mode is the key to the identification and differentiation of data link signals. In view of this, for the modulation modes (π/4-DQPSK, MSK, QPSK, 8PSK, BPSK, OQPSK) of the U.S. military Link-11, Link-16, Link-22 and CDL tactical data link signals, this paper proposes a tactical data link signal modulation recognition algorithm based on joint features. It mainly studies the extraction of four feature parameters of each modulated signal under Gaussian channels : high-order cumulant, square spectrum, fourth-order spectrum and high-order cumulant of differential signals. After that, several common tactical data link modulated signals are identified and classified by the decision tree. Finally, the simulation experiments shows that the algorithm has low computational complexity and high recognition rate, and has strong reliability and accuracy.

We investigate the interaction between self-interstitial atoms (SIAs) and 1/2 self-interstitial dislocation loops in tungsten (W) via atomistic simulations. We explore the variation of the anisotropic distribution of binding energies with the shapes and sizes of the 1/2[111] loop and the nonequivalent configurations of SIAs. For an arbitrarily shaped loop, SIA can be more easily trapped in the concave region of the loop than the convex region, which forms a loop whose curvature is closer to that of a circular loop. The direction of SIAs can largely affect the interaction behaviors with the loop. The capture distance of an SIA by the edge of a circular-shaped 1/2[111] loop is clearly elongated along the direction of the SIA; however, it weakly depends on the size of the loop. Then, we analyze the slanted ring-like capture volume of SIAs formed by the circular loop based on their generated anisotropic stress fields. Furthermore, the binding energies obtained from the elastic theory and atomistic simulations are compared. The results provide a reasonable interpretation of the growth mechanism of the loop and the anisotropic interaction that induces irregular-shaped capture volume, affording an insight into the numerical and Object Kinetic Monte Carlo simulations to evaluate the long-term and large-scale microstructural evolution and mechanical properties of W.

A pressing need in low energy spintronics is two-dimensional (2D) ferromagnets with Curie temperature above the liquid-Nitrogen temperature (77K), sizeable magnetic anisotropy. We studied Mn3Br8 monolayer which is obtained via inducing Mn vacancy at 1/4 population in MnBr2 monolayer. Such defective configuration is designed to change the coordination structure of the Mn-d5, to achieve ferromagnetism with sizeable magnetic anisotropy energy (MAE). Our calculations show that Mn3Br8 monolayer is a ferromagnetic (FM) half-metal and has Curie temperature of 130K, large MAE of -2.33 meV per formula unit, atomic magnetic moment of 13/3µB. Additionally, Mn3Br8 monolayer maintains to be FM under small biaxial strain, whose Curie temperature under 5% compressive strain is 160K. Additionally, both biaxial strain and carrier doping make the MAE increase, which mainly contributed by the magneto-crystalline anisotropy energy (MCE). Our designed defective structure of MnBr2 monolayer provides a simple but effective way to achieve ferromagnetism with large MAE in 2D materials.

How to build a high-performance liver-related computer assisted diagnosis system is an open question of great interest. However, the performance of the state-of-art algorithm is always limited by the amount of data and the quality of the label. To address this problem, we propose the biggest treatment-oriented liver cancer dataset for liver surgery and treatment planning. This dataset provides 216 cases (total about 268K frames) scanned images in contrast-enhanced computed tomography (CT). We labeled all the CT images with the liver, liver vasculature, and liver tumor segmentation ground truth for train and tune segmentation algorithms in advance. Based on that, we evaluate several recent and state-of-the-art segmentation algorithms, including 7 deep learning methods, on CT sequences. All results are compared to reference segmentations five error metrics that highlight different aspects of segmentation accuracy. In general, compared with previous datasets, our dataset is really a challenging dataset. To our knowledge, the proposed dataset and benchmark allow for the first time systematic exploration of such issues, and will be made available to allow for further research in this field.

Using a phase-field approach with the heat conduction equation, we predict the grain growth behaviors in tungsten (W) and their effects on effective thermal conductivity. Results show that the simulated grain growth kinetics is basically consistent with experimental observations. An empirical correlation is derived, describing the averaged grain area as a function of temperature and time. Further, we study the effect of grain growth, columnar crystal structure, and recrystallization on the effective thermal conductivity of W. It is found that the effective thermal conductivity increases nonlinearly with increasing grain size, and a simple correlation of converting two-dimension into three-dimension effective thermal conductivity is obtained. Interestingly, the effective thermal conductivity of the columnar crystal is relatively high along the elongated direction and higher than that of the isometric crystal. Nevertheless, the effective thermal conductivity decreases with the occurrence of the recrystallization due to the increased grain boundary density. Our results reveal that grain growth and grain structure can affect the capacity of heat transfer at high temperatures, which could be considered in the transient event of the long-time service of W materials in fusion devices.

The sudden outbreak of novel coronavirus 2019 (COVID-19) increased the diagnostic burden of radiologists. In the time of an epidemic crisis, we hope artificial intelligence (AI) to reduce physician workload in regions with the outbreak, and improve the diagnosis accuracy for physicians before they could acquire enough experience with the new disease. In this paper, we present our experience in building and deploying an AI system that automatically analyzes CT images and provides the probability of infection to rapidly detect COVID-19 pneumonia. The proposed system which consists of classification and segmentation will save about 30%–40% of the detection time for physicians and promote the performance of COVID-19 detection. Specifically, working in an interdisciplinary team of over 30 people with medical and/or AI background, geographically distributed in Beijing and Wuhan, we are able to overcome a series of challenges (e.g. data discrepancy, testing time-effectiveness of model, data security, etc.) in this particular situation and deploy the system in four weeks. In addition, since the proposed AI system provides the priority of each CT image with probability of infection, the physicians can confirm and segregate the infected patients in time. Using 1,136 training cases (723 positives for COVID-19) from five hospitals, we are able to achieve a sensitivity of 0.974 and specificity of 0.922 on the test dataset, which included a variety of pulmonary diseases., Highlights • We build a system for detecting COVID-19 infection regions. • We build a dataset of COVID-19. • It is easy to distinguish pneumonia from healthy cases.

Hypoxia induced injury of pulmonary microvascular endothelial barrier is closely related to the pathogenesis of acute lung injury after lung transplantation. VE-cadherin is an important structural molecule for pulmonary microvascular endothelial barrier. In this study, we aim to investigate the roles of VE-cadherin in hypoxia induced injury of pulmonary microvascular endothelial barrier.Rat model of hypoxia and cultured pulmonary microvascular endothelial cells (PMVECs) were utilized. Determination of PMVECs apoptosis, skeleton combination was conducted to verify the effects of hypoxia on injury of pulmonary microvascular endothelial barrier. In addition, VE-cadherin expression was modulated by administration of siRNA in order to investigate the roles of VE-cadherin in hypoxia induced PMVECs apoptosis and skeleton recombination.Our data indicated that expression of VE-cadherin was down-regulated in hypoxia-exposed PMVECs. Whereas, in the cells treated using siRNA, down-regulation of VE-cadherin did not trigger PMVECs apoptosis, but it increased the sensitivity of PMVECs to the hypoxia induced apoptosis. In cases of hypoxia, the expression of VE-cadherin was significantly down-regulated, together with endothelial skeleton recombination and increase of permeability, which then triggered endothelial barrier dysfunction.These data verify that VE-cadherin expression played an important role in hypoxia induced PMVECs apoptosis and cellular skeletal recombination.

Surface cleaning has always been an important procedure to improve quality and performance of final components in modern industrial manufacturing. Among various surface cleanings, laser cleaning has been identified as the most promising green cleaning technology to replace conventional mechanical and chemical cleaning. Laser cleaning is a green cleaning technology that will not result in environmental pollution. And, laser cleaning is a versatile, precise, and controllable technology. A set of laser cleaning system that consists of line structured light and industrial manipulator, was designed in this paper. The line structured light, combined with camera, was used to scan workpiece surface and reconstruct the 3D model of workpiece surface. The industrial manipulator was utilized to perform scanning and cleaning movements. This new system is called Laser Cleaning Robot (LCR). To improve automation level and cleaning efficiency of the LCR, a path generation method based on line structured light and industrial manipulator was proposed in this paper. Experimental results demonstrate the performance of the proposed method in terms of cleaning efficiency for large-scale workpiece.

Metals use a chemotaxis-like process to overcome diffusion limitations and prevent dendritic electrodeposition in batteries., The propensity of metal anodes of contemporary interest (e.g., Li, Al, Na, and Zn) to form non-planar, dendritic morphologies during battery charging is a fundamental barrier to achievement of full reversibility. We experimentally investigate the origins of dendritic electrodeposition of Zn, Cu, and Li in a three-electrode electrochemical cell bounded at one end by a rotating disc electrode. We find that the classical picture of ion depletion–induced growth of dendrites is valid in dilute electrolytes but is essentially irrelevant in the concentrated (≥1 M) electrolytes typically used in rechargeable batteries. Using Zn as an example, we find that ion depletion at the mass transport limit may be overcome by spontaneous reorientation of Zn crystallites from orientations parallel to the electrode surface to dominantly homeotropic orientations, which appear to facilitate contact with cations outside the depletion layer. This chemotaxis-like process causes obvious texturing and increases the porosity of metal electrodeposits.

The sudden outbreak of novel coronavirus 2019 (COVID-19) increased the diagnostic burden of radiologists. In the time of an epidemic crisis, we hoped artificial intelligence (AI) to help reduce physician workload in regions with the outbreak, and improve the diagnosis accuracy for physicians before they could acquire enough experience with the new disease. Here, we present our experience in building and deploying an AI system that automatically analyzes CT images to detect COVID-19 pneumonia features. Different from conventional medical AI, we were dealing with an epidemic crisis. Working in an interdisciplinary team of over 30 people with medical and / or AI background, geographically distributed in Beijing and Wuhan, we were able to overcome a series of challenges in this particular situation and deploy the system in four weeks. Using 1,136 training cases (723 positives for COVID-19) from five hospitals, we were able to achieve a sensitivity of 0.974 and specificity of 0.922 on the test dataset, which included a variety of pulmonary diseases. Besides, the system automatically highlighted all lesion regions for faster examination. As of today, we have deployed the system in 16 hospitals, and it is performing over 1,300 screenings per day.

Self-attention mechanisms have made striking state-of-the-art (SOTA) progress in various sequence learning tasks, standing on the multi-headed dot product attention by attending to all the global contexts at different locations. Through a pseudo information highway, we introduce a gated component self-dependency units (SDU) that incorporates LSTM-styled gating units to replenish internal semantic importance within the multi-dimensional latent space of individual representations. The subsidiary content-based SDU gates allow for the information flow of modulated latent embeddings through skipped connections, leading to a clear margin of convergence speed with gradient descent algorithms. We may unveil the role of gating mechanism to aid in the context-based Transformer modules, with hypothesizing that SDU gates, especially on shallow layers, could push it faster to step towards suboptimal points during the optimization process., Comment: Accepted at ACL 2020

Heat dissipation through interfaces becomes challenging in nanodevices which impedes the dissipation of waste heat. Accordingly, effective approaches are needed to optimize interfacial thermal transport. In this work, by combining the molecular dynamics simulations and machine learning technique, we systematically study the optimization of interfacial thermal transport in Si/Ge heterostructures through interfacial nanostructuring. Three structural parameters are proposed to describe the nanostructures at interfaces and applied to the machine learning driven predictions. The results demonstrate that the interfacial thermal transport significantly depends on the interfacial nanostructures and diverse guidances are discovered for the optimization. When fixing the density of nanostructures, the interfacial thermal resistance has a minimum at specific heights of nanostructures with small angles, while the minimum is gradually disappeared for the nanostructures with larger angles. When fixing the height of nanostructures, there is also a minimum versus density but gradually disappeared with increasing angles. The nonmonotonic dependences on density and height open spaces for the optimization of interfacial thermal transport. Our spectral decomposition analysis provides physical insights into machine learning predictions and optimizations. Finally, we also summarize the machine learning predictions from the perspective of contact area, in which the distinct dependencies on nanostructuring angle and height manifest the feasibility for the further optimization of interfacial thermal transport. Our machine learning driven study provides comprehensive knowledge and guidances for the optimization of interfacial heat dissipation in nanodevices through nanostructuring.

Construction of tunable and robust two-dimensional (2D) molecular arrays with desirable lattices and functionalities over a macroscopic scale relies on spontaneous and reversible noncovalent interactions between suitable molecules as building blocks. Halogen bonding, with active tunability of direction, strength, and length, is ideal for tailoring supramolecular structures. Herein, by combining low-temperature scanning tunneling microscopy and systematic first-principles calculations, we demonstrate novel halogen bonding involving single halogen atoms and phase engineering in 2D molecular self-assembly. On the Au(111) surface, we observed catalyzed dehalogenation of hexabromobenzene (HBB) molecules, during which negatively charged bromine adatoms (Brδ-) were generated and participated in assembly via unique C-Brδ+···Brδ- interaction, drastically different from HBB assembly on a chemically inert graphene substrate. We successfully mapped out different phases of the assembled superstructure, including densely packed hexagonal, tetragonal, dimer chain, and expanded hexagonal lattices at room temperature, 60 °C, 90 °C, and 110 °C, respectively, and the critical role of Brδ- in regulating lattice characteristics was highlighted. Our results show promise for manipulating the interplay between noncovalent interactions and catalytic reactions for future development of molecular nanoelectronics and 2D crystal engineering.

Thermal desorption of deuterium in tungsten pre-irradiated with the inert gas (helium, neon, argon) is modelled by TMAP (Tritium Migration & Analysis Program). Each TMAP model incorporates three activation energies linked with three types of traps respectively. First-principles method is performed to calculate the activation energies of deuterium detrapping from different kinds of defects. By comparing the activation energies modelled in TMAP with that obtained from first-principles method, the types of traps are determined. The pre-irradiation of helium can suppress the deuterium retention in vacancy clusters. Neon and argon pre-irradiation suppresses deuterium retention in mono-vacancies due to decreasing the number of mono-vacancies caused by the occupation of the inert gas atoms into mono-vacancies. The pre-irradiation of neon can facilitate deuterium retention in vacancy clusters through generating vacancy clusters during the injection process. Argon pre-irradiation facilitates deuterium retention mainly through generating voids, which are of a larger scale than vacancy clusters and can serve as effective traps.

Atomistic simulations have been used to investigate the core structures, static properties of isolated 1/2 screw dislocations, and their interaction with vacancies in bcc tungsten (W) based on three empirical interatomic potentials. Differential displacement maps show that only one embedded atom method potential is able to reproduce the compact non-degenerate core as evidenced by ab initio calculations. The obtained strain energy and stress distribution from atomistic simulations are, in general, consistent with elasticity theory predictions. In particular, one component of the calculated shear stress, which is not present according to elasticity theory, is non-negligible in the core region of our dislocation model. The differences between the results calculated from three interatomic potentials are in details, such as the specific value and the symmetry, but the trend of spatial distributions of static properties in the long range are close to each other. By calculating the binding energies between the dislocations and vacancies, we demonstrate that the dislocations act as vacancy sinks, which may be important for the nucleation and growth of hydrogen bubbles in W under irradiation.

Molecular dynamic simulation is utilized to study the nanocluster and the fuzz structure on the PFM surface of tungsten. The polyhedral and linear cluster structures based on the icosahedron, cuboctahedron and rhombic dodecahedron are built up. Three interatomic potentials are used in calculating the relationship between the cluster energy and the number of atoms. The results are compared with first-principles calculation to show each potential’s best application scale. Furthermore, the transition between the icosahedral and the cuboctahedral clusters is observed in molecular dynamic simulation at different temperatures, which follows a critical curve for different numbers of atoms. The linear structures are proved to be stable at experimental temperatures by thermodynamics. The work presents a selection of interatomic potentials in simulating tungsten cluster systems and helps researchers understand the growth and evolution laws of clusters and the fuzz-like structure formation process in fusion devices.

Tungsten (W) and W alloys are considered as the most promising candidates for plasma facing materials in future fusion reactor. Grain boundaries (GBs) play an important role in the self-healing of irradiation defects in W. Here, we investigate the stability of point defects [vacancy and self-interstitial atoms (SIA’s)] in a Σ5(3 1 0) [0 0 1] tilt W GB by calculating the energetics using a first-principles method. It is found that both the vacancy and SIA are energetically favorable to locate at neighboring sites of the GB, suggesting the vacancy and SIA can easily segregate to the GB region with the segregation energy of 1.53 eV and 7.5 eV, respectively. This can be attributed to the special atomic configuration and large available space of the GB. The effective interaction distance between the GB and the SIA is ∼6.19 A, which is ∼2 A larger than that of the vacancy-GB, indicating the SIA are more preferable to locate at the GB in comparison with the vacancy. Further, the binding energy of di-vacancies in the W GB are much larger than that in bulk W, suggesting that the vacancy energetically prefers to congregate in the GB.

The recombination of one Frenkel pair in tungsten has been investigated through first-principles simulation. Two different recombination types have been identified: instantaneous and thermally activated. The small recombination barriers for thermally activated recombination cases indicate that recombination can occur easily with a slightly increased temperature. For both of the two recombination types, recombination occurs through the self-interstitial atom moving towards the vacancy. The recombination process can be direct or through replacement sequences, depending on the vertical distance between the vacancy and the 〈1 1 1〉 line of self-interstitial atom pair.

Natural gas has been widely used around the world as a clean and environmental friendly energy. Natural gas hydrate blockage may form under a low temperature and high pressure condition, which will affect production process and even lead to severe accidents. In this paper, an identification method for gas hydrate blockage in pipeline based on acoustic excitation is presented, which can also work for pipeline leakage. An acoustic signal is transmitted into the pipeline by loudspeaker, then the reflected signals caused by hydrate blockage or leakage are acquired by a microphone near the loudspeaker. Empirical mode decomposition (EMD) method is employed to extract the eigenvectors of reflected signals, then a support vector machine (SVM) method is used to identify the types of reflected signals. Finally it is proved in the experiments that the proposed method can effective identify the hydrate blockage or leakage, and the identification accuracy rate is 97.5%.

This study presented an innovative method for phosphorus (P) recovery as vivianite from waste activated sludge (WAS) via optimizing iron dosing and pH value during anaerobic fermentation (AF). The optimal conditions for vivianite formation were in the pH range of 6.0–9.0 with initial PO43− >5 mg/L and Fe/P molar ratio of 1.5. Notably, FeCl3 showed advantages over ZVI for the simultaneous release of Fe2+ and PO43− during WAS fermentation, especially in acidic conditions. The FeCl3 dosing at pH 3.0 could contribute to 78.81% Fe2+ release and 85.69% of total PO43− release from WAS. They were ultimately recovered in the form of high-purity vivianite (93.67%). Clostridiaceae (40.25%) was the predominant bacteria in FeCl3-pH3 reactors, which played key roles in inducing dissimilatory iron reduction for Fe2+ formation. Therefore, P recovery as vivianite from WAS fermentation might be a promising and highly valuable approach to relieve the P crisis.

As a new class of non-coding RNA, circular RNAs (circRNAs) play crucial roles in the development and progression of various cancers. However, the detailed functions of circRNAs in cervical cancer have seldom been reported. In this study, circRNA sequence was applied to detect the differentially expressed circRNAs between cervical cancer tissues and adjacent normal tissues. The relationships between circCLK3 level with clinicopathological characteristics and prognosis were analyzed. In vitro CCK-8, cell count, cell colony, cell wound healing, transwell migration and invasion, and in vivo tumorigenesis and lung metastasis models were performed to evaluate the functions of circCLK3. The pull-down, RNA immunoprecipitation (RIP), luciferase reporter and rescue assays were employed to clarify the interaction between circCLK3 and miR-320a and the regulation of miR-320a on FoxM1. We found that the level of circCLK3 was remarkably higher in cervical cancer tissues than in adjacent normal tissues, and closely associated with tumor differentiation, FIGO stage and depth of stromal invasion. Down-regulated circCLK3 evidently inhibited cell growth and metastasis of cervical cancer in vitro and in vivo, while up-regulated circCLK3 significantly promoted cell growth and metastasis in vitro and in vivo. The pull-down, luciferase reporter and RIP assays demonstrated that circCLK3 directly bound to and sponge miR-320a. MiR-320a suppressed the expression of FoxM1 through directly binding to 3′UTR of FoxM1 mRNA. In addition, FoxM1 promoted cell proliferation, migration, and invasion of cervical cancer, while miR-320a suppressed cell proliferation, migration, and invasion through suppressing FoxM1, and circCLK3 enhanced cell proliferation, migration and invasion through sponging miR-320a and promoting FoxM1 expression. In summary, circCLK3 may serve as a novel diagnostic biomarker for disease progression and a promising molecular target for early diagnoses and treatments of cervical cancer.

International audience; We apply the Object Kinetic Monte Carlo method to simulate the hydrogen (H) clustering behaviour with large vacancy (V) clusters in tungsten. The main advantage of this method is to consider the temperature effects, large V clusters, and long-time evolution. It is thus a very useful tool to study the microstructure evolution of defects in irradiated materials covering from the atomic scale to mesoscale. Simulation results show that the number of trapped H atoms by V and V clusters decreases with the increase of temperature. This is expected because the de-trapping ability of H atoms increases when the temperature is increased. With the correction of the zero-point-energy in calculating binding energies, the present results show that the number of H atoms trapped by monovacancy decreases for all studied temperatures. We also found that the trapping ability of V clusters for H decreases with the increase of the sizes of V clusters, independent on temperature. The H concentration can largely affect the clustering behaviour of HmVn. When the H saturation concentration is reached, the clustering behaviour of HmVn is mainly determined by the sizes of V clusters.

Helium (He) has a synergistic effect on hydrogen (H) retention in metallic plasma-facing materials for nuclear fusion devices, which further makes a potential impact on hydrogen bubble formation in the materials. Using first-principles calculations, we investigated the interactions between H and He in molybdenum. The calculated results show that the binding energies of H are decreased at the pre-formed He-vacancy complex compared to those at the monovacancy without He. This indicates H trapping at the He-vacancy complex is energetically less favorable and the plasma-facing material will have less H retention. Most importantly, we revealed the critical characteristics of hydrogen concentration with the presence of He based on a thermodynamic model and the calculated energies of HmHeV complexes. The existence of He could apparently enhance the critical hydrogen concentration beyond which an initial stage of hydrogen bubble formation will occur. Our findings provide explicit evidences for the suppressing effect of helium on hydrogen bubble formation in molybdenum.

In this study, a rapid detection method based on near-infrared reflectance spectroscopy was proposed for measuring the contents of cellulose, hemicellulose and lignin in corn stover. In the basis of strategies of variable selection, feature extraction and nonlinear modeling, BiPLS-PCA-SVM was constructed using backward interval partial least squares combined with principal component analysis and support vector machine, which was used to improve the performance of spectral regression calibration model. For BiPLS-PCA-SVM model, the determination coefficients, root mean squared error and residual predictive deviation for the validation set were 0.906, 0.900% and 3.213 for cellulose; 0.987, 0.797% and 9.071 for hemicellulose; and 0.936, 0.264% and 4.024 for lignin, correspondingly. The results indicate that near-infrared reflectance spectroscopy combined with BiPLS-PCA-SVM can provide a reliable alternative strategy to detect contents of lignocellulosic components for pretreated corn stover in the anaerobic digestion process.

Surface cleaning is an essential procedure to improve quality and performance of workpiece in modern industrial manufacturing. Among surface cleaning technologies, laser cleaning has been regarded as the most promising green cleaning technology. Laser cleaning is a green cleaning technology that will not cause any environmental pollution. Laser cleaning has the ability of cleaning the area of the designated shape. A set of laser cleaning system that consists of two-dimensional galvanometer and 3-axis motion platform, was designed in this paper. The two-dimensional galvanometer was used to clean the area of the specified shape. The 3-axis motion platform expands the limited cleaning area of the two-dimensional galvanometer to a larger area. Laser displacement sensor is utilized to ameliorate the cleaning quality. To improve the cleaning accuracy of the system proposed in this article, a camera was adopted to recognize the origin of the workpiece and correct the pose of the workpiece. Experimental results demonstrate the performance of the proposed system for large-scale plane workpiece.

This paper proposes a new method to predict the corona onset voltage for a rod-plane air gap, based on the support vector machine (SVM). Because the SVM is not limited by the size, dimension and nonlinearity of the samples, this method can realize accurate prediction with few training data. Only electric field features are chosen as the input; no geometric parameter is included. Therefore, the experiment data of one kind of electrode can be used to predict the corona onset voltages of other electrodes with different sizes. With the experimental data obtained by ozone detection technology, and experimental data provided by the reference, the efficiency of the proposed method is validated. Accurate predicted results with an average relative less than 3% are obtained with only 6 experimental data.

A high hydrogen concentration at the sub-surface layers of tungsten plasma facing materials has been previously observed by experiments. We have performed the first-principles calculations to understand this experimental phenomenon. The layer-dependent hydrogen dissolution energies, vacancy formation energies and hydrogen trapping energies are calculated for the W(110) surface. Our results show that hydrogen dissolving into the vacancy-free sub-surfaces is energetically unfavorable. A surface tungsten vacancy is easier to form than in the bulk and has a large trapping effect on hydrogen dissolving. The present work demonstrates the important role of surface vacancies on the hydrogen retention in the tungsten sub-surfaces.