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The alignment precision of manual brush assembly for a precision conductive slip ring is critical to its performance of reliability and service lifetime. Currently, the alignment precision cannot be guaranteed since it largely depends on the operator's experiences and skill level. In this paper, a machine vision-aided method is proposed to measure the ring groove positions as the brush alignment objective, and track the relative brush position deviation during the manual brush alignment assembly. A vision-aided brush alignment assembly system is also developed to provide quantitative position deviation for the precise alignment of the brush and the ring groove, ensuring higher alignment accuracy and efficiency. The experimental results indicate that, with the developed system, the brush alignment assembly accuracy can be controlled within ±0.02 mm. [ABSTRACT FROM AUTHOR]

By a simple cross-substitution of A-site Li/Na in tetragonal tungsten bronze (TTB) structures, we successfully synthesized a new niobate compound, Pb2.15(Li0.25Na0.75)0.7Nb5O15, with a superstructure. This compound exhibits a strong second harmonic generation (SHG) up to ∼47 × KDP. The large SHG response is related to strengthened local distortion, manifesting cross-substitution as a possibly general route to improve the NLO effect in stiff and low symmetric structures. [ABSTRACT FROM AUTHOR]

The treatment of expired medical injections has always been a thorny environmental concern due to high liquid mobility and crispy glass bottle package. For this purpose, in this work, expired vitamin B1 (VB1) injections were recycled via the hydrothermal carbonization pelletizing and the following pyrolysis for the first time. The resultant VB1-derived N-doped carbon (VBNC) appeared as the morphology of regular micro-spheres with the mean diameter of 3.4 ± 0.7 μm. Furthermore, as the anode-active material in lithium ion battery (LIB), it also delivered high initial discharge capacity of 731 mAh g−1 at 0.025 A g−1 and the reversible discharge capacities of 358, 292, 203 and 118 mAh g−1 even at 0.5 A g−1, 1 A g−1, 2 A g−1 and 4 A g−1 for 500 cycles. Regular micro-spherical morphology and N-doping effect may jointly contribute into the satisfactory electrochemical performances, indicating high feasibility for LIB anode and offering a good strategy to recycle expired waste VB1 injections. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, p-toluene sulfonate (TsONa) doped polypyrrole (PPy) was synthesized for an anode in a lithium-ion battery via a one-step facile electropolymerization on Fe foil. The obtained TsONa-PPy-Fe composite electrode was investigated with scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and galvanostatic charge-discharge profiling. As expected, many irregular microspherical particles of TsONa-doped PPy formed and combined tightly with the surface of Fe foil. Furthermore, the obtained TsONa-PPy-Fe anode also delivered satisfactory electrochemical performances. For example, the reversible capacity was still about 105-115 mAh/g, even after at least 50 cycles. The high lithium storage activity of PPy and the high conductivity of the TsONa-doped PPy jointly contributed into the satisfactory electrochemical performances. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44935. [ABSTRACT FROM AUTHOR]

This paper performs degradation assessment and safety evaluation of a concrete gravity dam at Shenwo reservoir in Liaoning province of China by using two methods, i.e. deterministic method and probabilistic method, respectively. The deterministic responses of representative sluice piers are computed through static pushover and dynamic analyses. The probabilistic uncertainty analysis, including time invariant and time variant reliability analyses, is based on finite element (FE) reliability theory. For time invariant case, the material and loading parameters are considered as random variables, including elastic modulus, Poisson's ratio, mass density and pushover forces. For time variant case, the earthquake history is simulated by using random process, and the first-order reliability method (FORM) approximation combined with Koo's analytical solution is used to compute the mean upcrossing rate for given performance functions, through which the failure probabilities are calculated. Based on the analysis results using these two methods, the safety and reliability of the dam is assessed. Furthermore, the performance assessments of the dam in its current state are compared with those in the original state (i.e. when the dam was built) to quantify its performance degradation. Finally, the assessment results of using the deterministic and probabilistic methods are compared, and the discrepancies between them are quantified and explained. The computation is based on a general FE analysis platform for earthquake engineering simulation, OpenSees. [ABSTRACT FROM AUTHOR]

Zero thermal expansion (ZTE) alloys are dimensionally stable under the influence of heat, which is critical in high-precision components but remains rare among single phase materials. This work reports a single phase and nearly isotropic ZTE alloy (Hf 0.8 Nb 0.2)Fe 2.5 over a wide temperature range of 5–460 K (α l ≈ 1.07 × 10−6 K −1) via non-stoichiometric regulation. The introduction of excess Fe breaks the dual-phase nature of parent alloy, extends the magnetic ordering temperature, and induces a spin reorientation. The evolution of magnetic structure versus temperature gives rise to the ZTE behavior. The design concept of changing the internal magnetic interaction through non-stoichiometric regulation provides support for the discovery of novel ZTE materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Expired medicines and spent Li-anode batteries may result in the environment pollution and the waste of resource if they aren't reasonably recycled. In order to achieve the innocent treatment and the resource recovery, expired ferrous sulfate granules and waste Li foils were simultaneously recycled in the form of LiFePO 4 /C powders via the facile hydrothermal route. The obtained LiFePO 4 /C was investigated by methods of X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), energy dispersive X-ray spectrum (EDX), transmission electron microscope (TEM), galvanostatic charge/discharge and cyclic voltammetry (CV). As expected, the as-recycled LiFePO 4 /C powders consisted of many rod-like or sphere-like nanoparticles with the particle size about 60–400 nm. Furthermore, the resultant LiFePO 4 /C cathode delivered an initiate discharge capacity of 147.0 mAhg−1 at 0.1C and the reversible discharge capacity of 143 mAhg−1 after 50 cycles; even cycling at 5C and 10C for 500 cycles, the reversible discharge capacities remained about 123 mAhg−1 and 94 mAhg−1, respectively, comparable with those of pristine LiFePO 4 /C cathode. Obviously, the decent results may open a new way to develop the circular economy, which is very important in terms of the resource recovery and the environmental protection. Highlights • The expired ferrous sulfate and waste Li foils were simultaneously recycled. • Their recoveries were 78.9% and 77.3%, respectively. • The obtained LiFePO 4 /C cathode delivered the satisfactory performances. • The new connection between the waste resources and LiFePO 4 /C cathode was built. [ABSTRACT FROM AUTHOR]

Waste antibiotics into the natural environment are the large challenges to the environmental protection and the human health, and the unreasonable disposal of the expired antibiotics is a major pollution source. Herein, to achieve the innocent treatment and the resource recovery, the expired tetracycline was tried to be reutilized as the electrode active material in lithium ion battery (LIB) for the first time. The micro-structure and element component of the expired tetracycline were characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). Furthermore, the corresponding electrochemical performances were also investigated by galvanostatic charge/discharge and cyclic voltammetry (CV). To be satisfactory, the expired-tetracycline-based electrode delivered the initial specific discharge capacity of 371.6 mAh/g and the reversible specific capacity of 304.1 mAh/g after 200 cycles. The decent results will not only offer an effective strategy to recycle the expired tetracycline, but also shed a new light on the cyclic economy and the sustainable development. [ABSTRACT FROM AUTHOR]

The wide applications of metal Cu inevitably resulted in a large quantity of waste Cu materials. In order to recover the useful Cu under the mild conditions and reduce the environmental emission, waste Cu scraps were recycled in the form of CuCl powders with high economic value added (EVA) via the facile hydrothermal route. The recycled CuCl powders were characterized in terms of scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The results suggested that the recycled CuCl powders consisted of many regular tetrahedron-like micro-particles. Furthermore, in order to reduce the cost of lithium ion battery (LIB) anode and build the connection of waste Cu scraps and LIB, the recycled CuCl powders were evaluated as the anode active material of LIB. As expected, the reversible discharge capacity was about 171.8 mAh/g at 2.0 C even after 50 cycles, implying the satisfactory cycle stability. Clearly, the satisfactory results may open a new avenue to develop the circular economy and the sustainable energy industry, which would be very important in terms of both the resource recovery and the environmental protection. [ABSTRACT FROM AUTHOR]

Composite sodium p-toluenesulfonate/polypyrrole/TiO 2 nanotubes/Ti was designed and synthesized for sodium ion battery anode via facile electrochemical methods. The obtained composite sodium p-toluenesulfonate/polypyrrole/TiO 2 nanotubes/Ti (TsONa/PPy/TiO 2 NT/Ti) electrode was investigated in terms of SEM, EDX, FTIR, galvanostatic charge/discharge and AC impedance. As expected, the composite TsONa/PPy/TiO 2 NT/Ti electrode displayed higher electrochemical performances than the bare TiO 2 NT/Ti electrode. For example, the reversible capacity after 50 cycles was still as high as about 200 mAh/g, higher than 170 mAh/g of TiO 2 NT/Ti electrode. High Na-storage activities of both TiO 2 NT and TsONa/PPy, high conductivity of TsONa-doped PPy and the synergy effect among the various components may be responsible for the improved electrochemical performances. [ABSTRACT FROM AUTHOR]

Exchange bias (EB) is a crucial property with widespread applications but particularly occurs by complex interfacial magnetic interactions after field cooling. To date, intrinsic zero-field-cooled EB (ZEB) has only emerged in a few bulk frustrated systems and their magnitudes remain small yet. Here, enabled by high temperature synthesis, we uncover a colossal ZEB field of 4.95 kOe via tuning compensated ferrimagnetism in a family of kagome metals, which is almost twice the magnitude of known materials. Atomic-scale structure, spin dynamics, and magnetic theory revealed that these compensated ferrimagnets originate from significant antiferromagnetic exchange interactions embedded in the holmium-iron ferrimagnetic matrix due to supersaturated preferential manganese doping. A random antiferromagnetic order of manganese sublattice sandwiched between ferromagnetic iron kagome bilayers accounts for such unconventional pinning. The outcome of the present study outlines disorder-induced giant bulk ZEB and coercivity in layered frustrated systems.

Nano ferroelectrics holds the potential application promise in information storage, electro-mechanical transformation, and novel catalysts but encounters a huge challenge of size limitation and manufacture complexity on the creation of long-range ferroelectric ordering. Herein, as an incipient ferroelectric, nanosized SrTiO 3 was indued with polarized ordering at room temperature from the nonpolar cubic structure, driven by the intrinsic three-dimensional (3D) tensile strain. The ferroelectric behavior can be confirmed by piezoelectric force microscopy and the ferroelectric TO1 soft mode was verified with the temperature stability to 500 K. Its structural origin comes from the off-center shift of Ti atom to oxygen octahedron and forms the ultrafine head-to-tail connected 90° nanodomains about 2 to 3 nm, resulting in an overall spontaneous polarization toward the short edges of nanoparticles. According to the density functional theory calculations and phase-field simulations, the 3D strain-related dipole displacement transformed from [001] to [111] and segmentation effect on the ferroelectric domain were further proved. The topological ferroelectric order induced by intrinsic 3D tensile strain shows a unique approach to get over the nanosized limitation in nanodevices and construct the strong strain-polarization coupling, paving the way for the design of high-performance and free-assembled ferroelectric devices., Competing Interests: Competing interests statement:The authors declare no competing interest.

Tuberculosis (TB) is a prevalent and severe infectious disease that poses a significant threat to human health. However, it is frequently disregarded as there are not enough quick and accurate ways to diagnose tuberculosis. Here, we develop a strategy for tuberculosis detection to address the challenges, including an experimental strategy, namely, Double Adapter Directional Capture sequencing (DADCSeq), an easily operated and low-cost whole transcriptome sequencing method, and a computational method to identify hub differentially expressed genes as well as the diagnosis of TB based on whole transcriptome data using DADCSeq on peripheral blood mononuclear cells (PBMCs) from active TB and latent TB or healthy control. Applying our approach to create a robust and stable TB multi-mRNA risk probability model (TBMMRP) that can accurately distinguish active and latent TB patients, including active TB and healthy controls in clinical cohorts, this diagnostic biomarker was successfully validated by several independent cross-platform cohorts with favorable performance in differentiating active TB from latent TB or active TB from healthy controls and further demonstrated superior or similar diagnostic accuracy compared to previous diagnostic markers. Overall, we develop a low-cost and effective strategy for tuberculosis diagnosis; as the clinical cohort increases, we can expand to different disease kinds and learn new features through our disease diagnosis strategy.

Vector measurement is a vital measurement item during the satellite assembly, integration, and test (AIT) process. With the increasing popularity of commercial spaceflight, the development cycle of a satellite is shorter, and the number of satellites has been growing rapidly. The traditional on-site vector measurement method is inefficient and significantly affects the development cycle of the satellite. Therefore, it is of utter importance to propose an online high-precision automatic vector measurement system. The most challenging step of the online automatic vector measurement is coarse alignment because a cubic prism must be identified, and the normal direction of its surface must be calculated at a certain precision in the unstructured environment during the coarse alignment step. A reflection-based vision guide method was proposed to identify and calculate the normal direction of the cubic prism. The working principle and advantage of the proposed vision guide system were described in detail. What is more, the calibration and calculation methods of the proposed vision guide system were also presented. Finally, experiments were conducted to verify the effectiveness of the proposed method.

Zero thermal expansion (ZTE) alloys as dimensionally stable materials are usually challenged by harsh environmental erosion, since ZTE and corrosion resistance are generally mutually exclusive. Here, a high-performance alloy, Zr 0.8 Ta 0.2 Fe 1.7 Co 0.3 , is reported, that shows isotropic ZTE behavior (α l  = 0.21(2) × 10 -6 K -1 ) in a wide temperature range of 5-360 K, high corrosion resistance in a seawater-like solution compared with classic Invar and stainless Invar, and excellent cyclic thermal and structural stabilities. Such stabilities are attributed to the cubic symmetry, the controllable magnetic order, and the spontaneously formed passive film with Ta and Zr chemical modifications. The results are evidenced by X-ray/neutron diffraction, microscopy, spectroscopy, and electrochemistry investigations. Such multiple stabilities have the potential to broaden the robust applications of ZTE alloys, especially in marine services., (© 2022 Wiley-VCH GmbH.)

This paper presents a novel camera calibration method using a planar target with pure translation and a known translation distance. It only requires the straightness and position accuracy of the one-axis translational platform. There are theoretically no constraints among the normal direction of the planar target, the optical axis direction of the camera, and the moving direction of the translational platform. The paper analyzes the closed-form solution, followed by a nonlinear refinement based on the maximum likelihood criterion. Both computer simulation and real data are implemented to verify the effectiveness of the proposed method. Compared with Zhang's method, the proposed method realizes the camera calibration process automatically and evaluates the calibration process via the measurement accuracy of the calibrated camera, so it is a key factor to advance 3D computer vision one more step from expert to novice use.

Metallic materials that exhibit negligible thermal expansion or zero thermal expansion (ZTE) have great merit for practical applications, but these materials are rare and their thermal expansions are difficult to control. Here, we successfully tailored the thermal expansion behaviors from strongly but abruptly negative to zero over wide temperature ranges in a series of (Gd,R)(Co,Fe) 2 (R = Dy, Ho, Er) intermetallic compounds by tuning the composition to bring the first-order magnetic phase transition to second-order. Interestingly, an unusual isotropic ZTE property with a coefficient of thermal expansion of α l = 0.16(0) × 10 -6 K -1 was achieved in cubic Gd 0.25 Dy 0.75 Co 1.93 Fe 0.07 (GDCF) in the temperature range of 10-275 K. The short-wavelength neutron powder diffraction, synchrotron X-ray diffraction, and magnetic measurement studies evidence that this ZTE behavior was ascribed to the rare-earth-moment-dominated spontaneous volume magnetostriction, which can be controlled by an adjustable magnetic phase transition. The present work extends the scope of the ZTE family and provides an effective approach to exploring ZTE materials, such as by adjusting the magnetism or ferroelectricity-related phase transition in the family of functional materials.

Large-scale surfaces are prevalent in advanced manufacturing industries, and 3D profilometry of these surfaces plays a pivotal role for quality control. This paper proposes a novel and flexible large-scale 3D scanning system assembled by combining a robot, a binocular structured light scanner and a laser tracker. The measurement principle and system construction of the integrated system are introduced. A mathematical model is established for the global data fusion. Subsequently, a robust method is introduced for the establishment of the end coordinate system. As for hand-eye calibration, the calibration ball is observed by the scanner and the laser tracker simultaneously. With this data, the hand-eye relationship is solved, and then an algorithm is built to get the transformation matrix between the end coordinate system and the world coordinate system. A validation experiment is designed to verify the proposed algorithms. Firstly, a hand-eye calibration experiment is implemented and the computation of the transformation matrix is done. Then a car body rear is measured 22 times in order to verify the global data fusion algorithm. The 3D shape of the rear is reconstructed successfully. To evaluate the precision of the proposed method, a metric tool is built and the results are presented., Competing Interests: The authors declare no conflict of interest.

A laser stripe sensor has limited application when a point cloud of geometric samples on the surface of the object needs to be collected, so a galvanometric laser scanner is designed by using a one-mirror galvanometer element as its mechanical device to drive the laser stripe to sweep along the object. A novel mathematical model is derived for the proposed galvanometer laser scanner without any position assumptions and then a model-driven calibration procedure is proposed. Compared with available model-driven approaches, the influence of machining and assembly errors is considered in the proposed model. Meanwhile, a plane-constraint-based approach is proposed to extract a large number of calibration points effectively and accurately to calibrate the galvanometric laser scanner. Repeatability and accuracy of the galvanometric laser scanner are evaluated on the automobile production line to verify the efficiency and accuracy of the proposed calibration method. Experimental results show that the proposed calibration approach yields similar measurement performance compared with a look-up table calibration method., Competing Interests: The authors declare no conflict of interest.