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Zero thermal expansion (ZTE) alloys have unique aspects in the application of the engineering of precise dimensional control. However, the harsh conditions to realize ZTE, i.e., appropriate coupling among spin, lattice, and charge upon heating, have limited the ZTE alloys by very few numbers of species. In this work, we report a route to achieving two-dimensional (2D) ZTE behavior by regulating crystallographic texture and magneto-volume effects (MVEs) in volumetric positive thermal expansion alloys. This is illustrated in a series of MnxFe5−xSi3compounds by those earth-abundant elements. As a result, a 2D ZTE performance with a coefficient of thermal expansion αl= 0.45 × 10−7K−1over a broad temperature window of 10–310 K was observed in MnFe4Si3. The experimental results by synchrotron X-ray diffraction, neutron diffraction, microscopy, and magnetization measurements reveal that such a ZTE behavior is strongly coupled with fiber crystallographic texture and magnetic moment at the crystallographic 6g site that dominates MVEs in the a-bplane. The competition between ferromagnetic Fe4d-Fe6g(JFM) and antiferromagnetic Mn4d-Mn6g(JAFM) interactions makes the Mn1.5Fe3.5Si3and Mn2Fe3Si3compounds show mixed magnetism and negative thermal expansion (NTE). The integral approach presented here can be used to extend the scope of ZTE/NTE species in other magnetic or ferroelectric materials.

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.

The space deployable mast has been successfully applied to space equipment such as solar sails and space telescopes. At present, the deployable units of the space deployable mast mostly adopt the configurations of deployable units of FAST (Folding Articulated Square Truss), HIMAT, and ADAM (Able Deployable Articulated Mast). The configuration of the deployable unit is relatively few. Besides, there is a lack of ground micro-gravity environment simulation test devices for space deployable masts. This paper proposes the space deployable mast based on the double-layer deployable unit. Firstly, the configuration design method of the double-layer deployable unit based on the screw theory has been carried out. Three double-layer hybrid mechanisms serving as the basic units of the deployable mast have been obtained. Then, the kinematic and dynamic models of deployment of the space deployable mast have been established. And the deployment simulation based on MATLAB and Simscape has been performed. Furthermore, modal and static simulations have been performed to obtain the fundamental frequencies and maximum deformation displacements of the deployable masts consisting of 1, 2, 4, 8, and 12 units with and without cables. Finally, the ground test device has been developed to carry out the ground deployment test of the space deployable mast in the ground micro-gravity environment. It has been found that the ground test device could achieve the micro-gravity simulation level of 90.5%.

The Laves phases, a family of AB2-type intermetallic compounds, have attracted considerable attention in the fields of solid state chemistry and materials science. In this study, we synthesized a series of over-stoichiometric hexagonal Laves TiFe2Mnx(0 ≤ x≤ 1.0) compounds using a supercritical quenching method, specifically by quenching from a high-temperature near melting point (Tm). Neutron powder diffraction (NPD) studies reveal that the excess Mn atoms occupy both the Ti and Fe sites. Magnetic measurement demonstrates that these compounds display multiple magnetic states ranging from antiferromagnetic order (x= 0), mixed antiferromagnetic–ferromagnetic order (x≤ 0.3), to pure ferromagnetic order (0.3 < x< 0.4). Interestingly, a spin glass state emerges in the Mn-rich region (0.4 ≤ x≤ 1.0) below the frozen temperature. A detailed analysis using NPD, ac magnetic susceptibility, and isothermal remanent magnetization (IRM) relaxation measurements demonstrated that spin glass may originate from magnetic frustration interaction among the Mn moment in the A-layer and Mn/Fe moment at the B layer (Kagome layer). Our work broadens the pathway for synthesizing new magnetic functional materials in nonstoichiometric compounds.

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.

It has always been a widespread concern that countless waste cigarette butts cause resource waste and environmental pollution, so it is necessary to explore their recovery and reutilization. For this purpose, waste cigarette butts were recycled via pyrolysis carbonization at 700 °C and 800 °C for sodium ion battery (SIB) anode, respectively. The results suggested that the micro-structure and electrochemical Na-storage performances of N-doped waste cigarette butts hard carbon (NWHC) were affected by the carbonization temperature. For example, NWHC carbonized at 700 °C (NWHC-700) possessed lower degree of graphitization, higher content of N element and larger interlayer spacing than NWHC at 800 °C (NWHC-800). And also, NWHC-700 anode delivered the reversible discharge capacities of 300 mAh g−1at 25 mA g−1for 200 cycles and 135 mAh g−1even at 1500 mA g−1for 2000 cycles, higher than 241 mAh g−1and 105 mAh g−1of NWHC-800 anode, respectively. More disordered micro-structure, lower degree of graphitization, larger interlayer spacing and higher content of N element of NWHC-700 anode may be jointly responsible for higher electrochemical Na-storage performances, which would delay the afflux of the waste cigarette butts into the waste streams.

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 αl= 0.16(0) × 10–6K–1was achieved in cubic Gd0.25Dy0.75Co1.93Fe0.07(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.

Expired medicines in the environment may cause the pollution and resource waste if they are not reasonably recycled. Therefore, it is very instructive to exploit the non-medical values of expired medicines. Herein, such an attempt to recycle expired aminophylline was made as the anode active material of lithium ion batteries (LIBs) for the first time. The microstructure and chemical element component of the expired aminophylline were confirmed by using the methods of scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Furthermore, the feasibility of using an expired-aminophylline-based anode in LIBs was evaluated by galvanostatic charge/discharge and cyclic voltammetry. To be satisfactory, the reversible specific discharge capacities of expired-aminophylline-based anode were maintained at 268·8 mAh/g at 50 mA/g for 200 cycles and 140 mAh/g even at 500 mA/g for 1000 cycles. In addition, after coupling with a commercial lithium cobalt (III) oxide (LiCoO2) cathode, the resultant full cell also delivered 130 mAh/g at the 100th cycle at 100 mA/g. These satisfactory results may not only pave a way for the reasonable exploitation of the non-medical values of expired medicines but also offer good inspiration and strategy to develop sustainable energy and circular economy.

As one kind of metal–organic framework material, zinc l-phenylalanine chelate may combine the merits of organic and inorganic components at the molecular level, thus making it a preferred anode active material. However, reports about zinc l-phenylalanine chelate anodes for lithium (Li) ion batteries are still scarce at the moment. Herein, shape-controlled synthesis of zinc l-phenylalanine chelate was carried out through a facile liquid-phase precipitation reaction and subsequent lyophilization. The obtained zinc l-phenylalanine chelate was investigated by field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis, galvanostatic charge/discharge and cyclic voltammetry. The results suggest that zinc l-phenylalanine chelate appeared as uniform nanofibers about 140 nm diameter and 2–5 μm long. Furthermore, the zinc l-phenylalanine chelate nanofiber anode exhibited satisfactory electrochemical performances. For example, the initial specific discharge capacity was as high as 255 mAh/g at 100 mA/g and the reversible capacity remained 109 mAh/g even at 1000 mA/g for 200 cycles. Additionally, the possible lithium-storage mechanism was also explored. The synergistic effect of the combination of organic/inorganic components at the molecular level, regular nanofiber-like morphology and structural cavities may facilitate good strain accommodation, short ionic/electronic transport paths and high electrochemical performance.

It is very important to recycle the waste biomass resources for the environment protection and the circular economy. For this purpose, the waste old loofah was carbonized at 800°C for 1 h in the inert nitrogen gas (N2) atmosphere for lithium ion battery anode. The resultant waste-loofah-derived carbon was investigated by scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, nitrogen adsorption and desorption, galvanostatic charge/discharge, cyclic voltammetry and alternating current impedance. The results suggested that the waste-loofah-derived carbon powders consisted of many concomitant microparticles and nanoparticles with a specific surface area of about 492 m2/g. Furthermore, the waste-loofah-derived carbon anode also delivered high electrochemical lithium (Li) storage activity. For example, the initial specific discharge capacity was about 697 mAh/g, and the reversible discharge capacity was about 187 mAh/g at 1000 mA/g for 500 cycles and still about 98 mAh/g even at 3000 mA/g for 500 cycles, exhibiting good cycling stability. High surface area and structural defects may jointly contribute to high electrochemical performances.

Metals typically crystallize in highly symmetric structures due to their nondirectional and nonsaturated metallic bonds. Here, we report that terbium metal in its ferromagnetic state adopts an unusual low-symmetry orthorhombic structure with a Cmcmspace group. A similar structure has been previously observed only in a few actinide metals with bonding 5f electrons at ambient pressure, such as uranium, neptunium, and plutonium, but with different nearest coordination numbers and bond-length variations. The Tb atom occupies the 4c site (0, ∼0.1661, 1/4), building up −[Tb–Tb]– layers stacking along the b-axis. Our first-principles many-body calculations of the crystal field splitting in the correlated Tb 4f-shell demonstrate that the Cmcmstructure for ferromagnetic terbium is stabilized by magneto-elastic forces due to a secondary order of quadrupolar moments in the ferromagnetic state. These findings are significant for further understanding of the nature of terbium, including its electron structure, energy bands, phonons, and magnetism.