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Abstract Molybdenum diselenide (MoSe 2) nanosheets thin film gas sensor was firstly fabricated and its sensing potential to ppm-level ethanol vapor at low operating temperature was investigated. Ultrathin MoSe 2 nanosheets were prepared in large scale through a facile liquid-phase exfoliation method using low-boiling-temperature solvent. The exfoliated MoSe 2 nanosheets exhibited high purity and crystallinity with few atomic layer thickness. Systematical gas sensing tests demonstrated that MoSe 2 nanosheets based thin film could be utilized as ethanol gas sensor with linear response, quick recovery, and good repeatability at 90 °C. The sensing mechanism of MoSe 2 toward ethanol was investigated based on first principle calculation. The adsorption behavior of ethanol molecules on MoSe 2 surface was revealed in light of adsorption orientation, adsorption energy, charge transfer, projected electronic density of state, and molecular orbital. The calculation well matched with experimental results. It is found the quick and completed recovery of MoSe 2 nanosheets sensor was benefited by the appropriate physical interaction between ethanol and MoSe 2 surface. This finding offers a competitive option instead of conventional graphene sensor for ethanol gas detection at low temperature. [ABSTRACT FROM AUTHOR]

This study employed first principles calculations to investigate Fe-doped Bi4O5Br2 as a potential photocatalyst with high efficiency. Based on formation energy calculation, the Fe atoms prefer to replace the Bi atoms with coordination bond of 3, and the optimal concentration for Fe-doping is 6.06 wt.%. From surface energy calculations, the (1 0 1 ̄) surface has the lowest surface energy, and therefore the easiest cleavage facet is { 1 0 1 ̄ }. The key factors for the improvement of photocatalytic efficiency after Fe-doped Bi4O5Br2 are estimated as follows. First, the band gap decreases from 2.63 eV in pristine case to 2.40 eV in 4 Fe-doped Bi4O5Br2 case, resulting in the photon absorption edge shift to lower energy range and the absorption coefficient increase. Secondly, the work functions decrease from 5.66 eV (pristine) to 4.92 eV (4 Fe-doped Bi4O5Br2), which facilitate the electrons escaping from the surface. Thirdly, the relative mass ratio of photo-induced electrons and holes increases with Fe concentration. Because the Fe 3 d impurity states in the forbidden band gap become wider, the relative ratio increased after Fe-doped Bi4O5Br2. Finally, the Fe doping process introduces more active sites on the surface, which can effectively improve the capacity of target molecules adsorption. Therefore, it is reasonable to believe that Fe-doped Bi4O5Br2 can effectively improve the photocatalytic efficiency because the abovementioned key factors have tremendously improved. Our work provides a reasonable reason for choosing Fe as a dopant, which can help our experimental work and provide explanation for photocatalytic efficiency improvement. The band gap decrease induce more photon absorption in lower energy range. The relative effective mass ratio of e–/h+ increase, result in higher separation efficiency. The Fe dope introduce more and stronger active sites. [ABSTRACT FROM AUTHOR]

Hydrocephalus is a common neurological disease in humans, but a uniform and particularly effective hydrocephalic animal model amenable to proper appraisal and deep study has not yet been established. In this study, we attempted to construct a high-efficiency model of hydrocephalus via intraventricular kaolin injection. Adult male Sprague-Dawley rats were randomly divided into 2 groups: the control group (n = 15) and the experimental group (n = 30). Kaolin was injected into the lateral ventricle of experimental animals. Control rats underwent the same procedure but received sterile saline injection instead of kaolin. All animals with kaolin injection into the lateral ventricle developed hydrocephalus according to magnetic resonance imaging (MRI) results (success rate up to 100%). Also, the Morris water maze (MWM) test demonstrated disturbed spatial learning and memory. Furthermore, there were significant differences between groups with respect to the histological changes in the periventricular tissue. Our results indicate that experimental hydrocephalus induced by lateral ventricle injection of kaolin in adult rats is feasible and may be widely used. [ABSTRACT FROM AUTHOR]

Ti-doped LiB (001) is a promising material for hydrogen storage. The adsorption of H2 is greatly enhanced by doping Ti into LiB (001), change the electronic structures of the surface Li, B atoms. After H2 is adsorbed on the surface, the Ead of the (H2)n@Ti/LiB (001) system is considered. It is around -0.22 eV/H2 to -0.31 eV/H2, which is close to the target specified by U.S. Department of Energy. The nature of the bonding between Ti and H2 is due to the H 1s, Ti 4s and B 2s orbital hybridization. In addition, Ti 3d orbital is hybridized strongly with B-2p orbital, resulting in more stable Ti/LiB (001) system. These results are verified by the electron density distribution intuitively. It is found that the system can adsorb up to four H2 at ambient temperature and pressure. Therefore, the Ti-doped LiB (001) would be a promising hydrogen storage material. Such optimal molecular hydrogen adsorption system makes H2 adsorption feasible at ambient conditions, which is critical for practical applications. [ABSTRACT FROM AUTHOR]

Background: Shunt obstruction is a type of ventriculoperitoneal shunt (VPS) failure. Whether changes in cerebrospinal fluid (CSF) parameters can influence shunt outcomes or not is debatable. Methods: In this study, we retrospectively included adult hydrocephalus patients who received VPS from 6 general hospitals in different provinces of China from November 2013 to September 2021. The inclusion criteria: Patients with hydrocephalus of all etiologies underwent shunt surgery from 6 general hospitals in different provinces of China were included in the study. The exclusion criteria: 1.Patients under the age of 18; 2.Patients who had previous shunt surgery; 3. Shunt failure from other factors; 4.Patients died from other causes; 5. Patients with incomplete data. The CSF of shunt patients had been analyzed at the time of shunt insertion. The CSF samples were collected and analyzed when the shunt was implanted. The relationship between CSF parameters and the incidence rate of shunt obstruction in one year was analyzed. Results: A total of 717 eligible patients from 6 hospitals were included, of whom 59(8.23%) experienced obstruction. Multivariate logistic regression analysis identified that protein level(odds ratio [OR] 1.161, 95% CI 1.005 ~ 1.341, p = 0.043), decreased glucose level(< 2.5 mmol/L)(odds ratio 3.784, 95% confidence interval 1.872 ~ 7.652, p = 0.001) and protein level increase(> 0.45 g/L) (odds ratio 3.653, 95% confidence interval 1.931 ~ 6.910, p = 0.001)were independent risk factors of shunt obstruction. Conclusion: This study suggested that increased protein level (> 0.45 g/L) and decreased glucose level (< 2.5 mmol/L) in CSF indicated an increased risk of shunt obstruction in a patient with hydrocephalus. Thus, shunt surgery should be more carefully considered when the CSF glucose and protein were abnormal. [ABSTRACT FROM AUTHOR]

This article proposes a biomimetic multilayer foam-filled structure (BMFS) that mimics the microstructural characteristics of biological structures such as human bone and whale baleen. The lateral compression performance of such structures is investigated using experimental and numerical analyses. The proposed structure consists of three layers of aluminum foam with different densities filled in several concentric circular aluminum tubes. The test includes a solid design (Design-1) and a hollow design (Design-2). A series of quasi-static compression tests and finite element simulations are conducted, and the results show that BMFS exhibits a more advantageous sequential collapse deformation pattern for practical use. An energy absorption analysis of each layer shows that the energy absorption ratio of the foam layer reaches 85%. Comparing Models 1–3 of the two designs shows that the energy efficiency decreases, and the work efficiency increases, as the foam density increases. In addition, the interaction between the tubes and foams enhances the energy absorption properties of the structure. The parameter study shows that the energy absorption characteristics of Design-2 are insensitive to the diameter of the tube. The SEA of Design-1 increases with the thickness of Tube-1. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to study the influence of lubricant temperature-viscosity on the performance for a hydrodynamic journal floating ring bearing (FRB), including ring-journal speed ratio and stability. Design/methodology/approach: The finite difference method was used to solve computational models of Reynolds equation, energy equation and temperature–viscosity equation. Dynamic coefficients were obtained based on the floating ring balance. The dynamic model of journal and floating ring was established to deduce the stability criterion of single mass symmetrical rigid FRB rotor system by the Routh–Hurwitz method. The outlet temperature and ring-journal speed ratio under different journal speeds were compared to experimental data. Findings: The temperature–viscosity effect reduces the ring-journal speed ratio and stability of rotor system. According to theoretical and experimental results, the outlet temperature rises and ring-journal ratio drops when the journal speed rises. Originality/value: The temperature–viscosity effect is combined with dynamic characteristics to analyze the stability of the rotor system and lubrication mechanism for an FRB. Influence of temperature–viscosity on the ring-journal ratio and multi-stable regions of system are studied. [ABSTRACT FROM AUTHOR]

Highlights • Interval linguistic hesitant fuzzy preference relations are presented. • An additive consistency concept is defined. • Models for judging consistency and determining missing values are constructed. • Two equivalent methods for ranking objects are provided; • An additive consistency and consensus-based algorithm is developed. Abstract This paper introduces a new type of fuzzy sets called interval linguistic hesitant fuzzy sets (ILHFSs), which can address the qualitatively uncertain preferences of decision makers as well as reflect their hesitancy. Such fuzzy sets endow the decision makers with more flexibility: (i) several interval linguistic variables are allowed to represent a judgment, and (ii) the number of interval linguistic variables can be different for different preferences. To show the application of ILHFSs, a group decision-making method with interval linguistic hesitant fuzzy preference relations (ILHFPRs) is introduced. To achieve this goal, an additive consistency concept for ILHFPRs is presented to derive the rational rankings. Following this concept, a programming model for judging the additive consistency of ILHFPRs is constructed. Then, an additive consistency-based programming model is established to ascertain missing values in incomplete ILHFPRs. Subsequently, an approach for calculating the interval linguistic hesitant fuzzy priority weight vector from incomplete and inconsistent ILHFPRs is presented. To measure the agreement degree of the decision makers' judgements, a consensus index is offered, and a method for determining the weights of the decision makers is proposed. Finally, a numerical example about evaluating commodity sales platforms in China is chosen to illustrate the utilization of the new method. The results extend and perfect the application scope of preference relations, which offer the decision makers more choices to express their judgments. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Ternary Bi-BiOI/graphene photocatalyst was synthesized by solvothermal method. • The composite photocatalyst can harness from visible to NIR spectrum. • Bi-BiOI/graphene shows efficient photocatalytic activity for NO oxidation removal. • O 2 – radical species play the most critical role in the photocatalytic process. Abstract In order to further improve its photocatalytic activity, the BiOI microspheres were activated by a synchronous coupling of Bi metal and graphene under solvothermal conditions. The effects of the synthesis temperature (160–200 °C) on crystallinity, morphology, and photocatalytic activity were studied in particular. As expected, the ternary Bi-BiOI/graphene photocatalyst synthesized at 180 °C exhibited higher photocatalytic activity for NO oxidation removal under visible light irradiation than individual BiOI, and binary Bi-BiOI and BiOI/graphene composites. The photocatalytic efficiency for the NO removal of the ternary Bi-BiOI/graphene photocatalyst synthesized at 180 °C reached 51.8% within 30 min of visible light irradiation. The enhanced photocatalytic activity of the ternary Bi-BiOI/graphene photocatalyst is attributed to (I) the efficient transfer of photo-generated electrons from BiOI and Bi to graphene, leading to the effective separation of the photo-generated electron-hole pairs and (II) the surface plasmon resonance effect of Bi nanoparticles in the composite photocatalyst. Furthermore, the results of the scavenger experiments and DMPO-ESR spin-trapping measurements reveal that O 2 − radical species play the most critical role and holes serve as a secondary active species in the oxidative removal process of NO by 180BOI/GR composite under visible light irradiation. [ABSTRACT FROM AUTHOR]

The detection of PCB defect quality plays an important role in PCB fabrication. However, the size of the PCB defects is too small to identify. In order to improve the detection efficiency of existing algorithms, a joint multiscale PCB defect target detection and attention mechanism, which named RAR-SSD, was proposed. By using lightweight receptive field block module (RFB-s) with an attention mechanism module, we built a wider range of effective focused features, which exploited the importance of different features in different channels without increasing the computing power of the network. In addition, we built a feature fusion module to efficiently fuse low-level feature information with high-level feature information to produce a more complete feature map and improve the accuracy of fault recognition. The proposed network improved the fault recognition accuracy of PCBs by 2.23% over the original SSD algorithm, with a recall rate of 6.51% and an F1 value of 4.85%, the model has greatly improved in terms of detection performance. The optimized algorithm has significant speed and accuracy advantages over the algorithms YOLOv3 and YOLOv5. Experimental results show that the proposed RAR-SSD model has good performance in detecting small and medium size targets for defects in the PCB manufacturing process and is of some guidance for the subsequent detection of PCB defects. [ABSTRACT FROM AUTHOR]

Vibration procedures significantly affect the performances of cement-based materials. However, studies on the distribution of certain particles within cement-based materials are limited due to the complexity and difficulty of identifying each specific particle. This paper presents a new method for simulating and quantifying the movements of particles within cement paste through the use of "tagged materials". By separating the tagged particles from the cement paste after vibration, the distribution of the particles in the cement paste can be calculated statistically. The effect of the vibration time and frequency, fresh behavior, and powder characteristics of cement paste on particle motions are investigated. The results demonstrate that when the vibration exceeds 1800 s, it induces a significant uneven dispersion of microparticles. This effect is more pronounced at low viscosities (<1 Pa·s) of cement paste or high vibration frequencies (>200 Hz). Larger and denser particles exhibit greater dispersion. This method provides a valuable tool for investigating the theory of particle motion in cement paste, which is crucial for understanding the influence of vibration on the properties of cement-based materials. [ABSTRACT FROM AUTHOR]

Ammonia (NH 3) detection is crucial for both harnessing hydrogen energy and safeguarding public health. However, the NH 3 sensors based on semiconductors is currently constrained by their necessity to operate at elevated temperatures and their limited ability to distinguish NH 3 from other gases. In this study, the high oxygen vacancy W@WO 2.92 core-shell nanostructures have been synthesized by pulsed laser ablation in water. The gas sensors based on W@WO 2.92 nanoparticles response to NH 3 with high sensitivity (|R a -R g |/R a =72.6 %@100 ppm, R a and R g represent the resistance of the material when exposed to air and the test gas, respectively.) at room temperature with detection limit of 730 ppb. Additionally, the response to NH 3 can achieve 55 % even at 5℃, which plays a great role in timely detection of NH 3 during low temperature transportation. Furthermore, the sensors reveal outstanding selectivity toward NH 3 in the presence of 11 other potential interfering gases. This research presents a groundbreaking strategy, holding significant potential for the development of high-performance NH 3 sensors that operate efficiently at low temperatures. [Display omitted] • The W@WO 2.92 core-shell nanoparticles were fabricated by pulsed laser ablation in liquid. • The W core can donate electrons to WO 2.92 shell, improving the ammonia sensing performance of WO 2.92. • The W@WO 2.92 -based NH 3 sensors can operate from 5°C to RT with an exceptional sensitivity and unparalleled selectivity. [ABSTRACT FROM AUTHOR]

In this work, a prediction model, which can be used to reveal the corrosion mechanism and behavior of Mg-RE-Ni alloys, was successfully developed with machine learning. The model is constructed based upon the microstructure parameters of LPSO phase, and the accuracy of the prediction model is greater than 93 %. The results agree well with the literature when it is used to study the relationship of composition-structure-corrosion behavior of Mg-RE-Ni alloys. This work solves the shortcomings of experimental studies, which provide a route to quantitively analyze and reveal the corrosion mechanism of Mg-RE-Ni alloys. • The microstructure characteristics of LPSO phase are quantitatively evaluated. • A accurate composition-structure-corrosion behavior prediction model is developed. • The corrosion mechanism in Mg-RE-Ni alloy is quantitatively revealed by machine learning. [ABSTRACT FROM AUTHOR]

[Display omitted] • Theoretical assessment on chirality-, width- and functionalization-dependent work function of Ti 2 B (MBene) nanoribbon is performed by DFT study. • The work function of Ti 2 B nanoribbons has been discussed in terms of the non-equivalent edges and the halogen termination. • The work function variation of the Ti 2 B nanoribbons has been explained by the edge dipole moments caused by the edge's charge redistribution, halogen electronegativity, and edge reconstruction. One-dimensional nanoribbons have foreshadowed potential applications in nanoelectronics due to their fascinating quantum confinement effects. We present theoretical assessment from first-principles calculations to explore the work functions of Ti 2 B-based MBene nanoribbons, focusing on the size, edge, and functionalization dependencies. We found that the bare and halogen-functionalized Ti 2 B nanoribbons exhibit metallic properties and chemical stability. The work function of both bare and halogen-terminated armchair Ti 2 B nanoribbons tends to saturate as width. In contrast, the work function of zigzag Ti 2 B nanoribbons varies complexly with width and has been discussed in terms of the non-equivalent edges and halogen termination. The work functions of halogen-terminated Ti 2 B nanoribbons have been found to be significantly affected by the edge dipole moments, which are determined by three factors: functionalization-induced electron redistribution at the edge, the electronegativity of halogen functional groups, and the edge reconstruction. These findings provide valuable insights for designing, characterizing, and utilizing the proposed nanostructures. [ABSTRACT FROM AUTHOR]