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Material handling tasks often lead to skeletal injury of workers. The whole-body static biomechanical modeling method based on virtual humans is the theoretical basis for analyzing the human factor index in the lifting process. This paper focuses on the study of humans’ body static biomechanical model for virtual human ergonomics analysis: First, the whole-body static biomechanical model is constructed, which calculates the biomechanical data such as force and moment, average strength, and maximum hand load at human joints. Secondly, the prototype model test system is developed, and the real experiment environment is set up with the inertial motion capture system. Finally, the model reliability verification experiment and application simulation experiment are designed. The comparison results with the industrial ergonomic software show that the model is consistent with the output of the industrial ergonomic software, which proves the reliability of the model. The simulation results show that under the same load, the maximum joint load and the maximum hand load are strongly related to the working posture, and the working posture should be adjusted to adapt to the load. Upright or bent legs have less influence on the maximum load capacity of the hand. Lower hand load capacity is due to forearm extension, and the upper arm extension greatly reduces the load capacity of the hand. Compared with a one-handed load, the two-handed load has a greater load capacity.

Surrounding rock deformation prediction can provide decision-makers with future deformation information, which enhances construction safety. Aiming at the problems of nonlinearity, high dynamics, and low prediction accuracy of surrounding rock deformation, this article proposes a time series prediction method based on the sparrow search algorithm (SSA)-variational mode decomposition (VMD)-gated recurrent unit (GRU) deep learning model. First, aiming at the problem that parameters in VMD are difficult to determine, a VMD evaluation standard in the field of surrounding rock deformation is proposed, and the SSA is used to find the optimal combination of decomposition parameters under this standard. Second, the VMD with optimal parameters is used to decompose the surrounding rock deformation series into the trend and random term displacement. Finally, a GRU neural network with memory and feedback capabilities is built to predict the displacement components separately, and superimposed reconstruction is performed to obtain the final predicted values. The proposed method is applied to the prediction of peripheral rock deformation in a tunnel and compared with the traditional model. The results show that the proposed SSA-VMD-GRU model can accurately predict rock deformation, and the prediction accuracy of each displacement component is high, and the error is small. The final predicted of the two groups of deformation sequences were 0.9265 and 0.9119, root mean square error were 0.1262 and 0.1243 mm, and mean absolute error were 0.1101 and 0.1062 mm, respectively. This research provides an efficient and reliable solution for the prediction of surrounding rock deformation.

Porous graphitic carbon nanorings (PGCNs) are proposed by smart catalytic graphitization of nano-sized graphene quantum dots (GQDs). The as-prepared PGCNs show unique ring-like morphology with diameter around 10 nm, and demonstrate extraordinary mesoporous structure, controllable graphitization degree and highly defective nature. The mechanism from GQDs to PGCNs is proven to be a dissolution-precipitation process, undergoing the procedure of amorphous carbon, intermediate phase, graphitic carbon nanorings and graphitic carbon nanosheets. Further, the relationship between particles size of GQDs precursor and graphitization degree of PGCNs products is revealed. The unique microstructure implies PGCNs a broad prospect for energy storage application. When applied as negative electrode materials in dual-carbon lithium-ion capacitors, high energy density (77.6 Wh·kg −1 ) and super long lifespan (89.5% retention after 40,000 cycles at 5.0 A·g −1 ) are obtained. The energy density still maintains at 24.5 Wh·kg −1 even at the power density of 14.1 kW·kg −1 , demonstrating excellent rate capability. The distinct microstructure of PGCNs together with the strategy for catalytic conversion from nanocarbon precursors to carbon nanorings opens a new window for carbon materials in electrochemical energy storage.

Complex wind and temperature characteristics in the Yellow River basin (YRB) challenge the safety and durability of long-span concrete-filled steel tube (CFST) bridges greatly. To address this issue, it is important to accurately assess the joint actions of wind and temperature. In this paper, the joint actions of wind and temperature in eight typical YRB cities are analyzed. The joint distributions of wind speed and air temperature are developed with the Archimedean Copula, and the Kendall return period is used for occurrence probability estimations. Eight wind–temperature combinations are considered. Responses for these combinations are calculated and compared with specification actions. Results show significant wind–temperature variations in the YRB. When wind actions adopt the univariate representative values (URVs), the temperature actions are reduced by 20–40%; when temperature actions use URVs, wind actions experience a reduction by more than half of their URVs. The joint responses can sometimes exceed, but are mostly less than, the specification responses, with a maximum strength margin over 11 MPa. These efforts suggest that the proposed joint actions can expand the provisions in the General Specification and provide guidance for the design of long-span CFST bridges.

Cu and Fe are the main impurity elements in the hydrometallurgical regeneration of spent lithium‐ion batteries. Hence, it is important to study the effect of Cu and Fe doping on the structures and electrochemical properties of cathode materials. In this study, a series of Cu‐ and/or Fe‐doped LiNi0.8Co0.15Al0.05O2 cathode materials are synthesized by spray pyrolysis and high‐temperature solid‐state method. The inductively coupled plasma (ICP), X‐ray diffraction (XRD), and Rietveld refinement results reveal that Cu and Fe can incorporate into the crystal lattice and cation mixing is suppressed. The X‐ray photoelectron spectroscope (XPS) results show that the relative ratio of Ni2+/Ni3+ on the surface is effectively decreased. Electrochemical results display that the electrochemical performances of Cu‐ and/or Fe‐doped samples are improved when the atomic ratio of Ni to Cu and Ni to Fe is greater than 79.0 and 399.0, respectively. The dQ/dV, GITT, EIS, XRD, and XPS studies indicate that the structure stability, Li+ diffusion coefficient, and charge transfer can be increased by appropriate Cu and/or Fe substitution. The results suggest that appropriate Cu and Fe can be doped into LiNi0.8Co0.15Al0.05O2 as beneficial elements rather than removed as impurities. The electrochemical performances can be improved by Cu and Fe doping. The mechanism of the effect of Cu and Fe doping on the material is studied. Spent lithium‐ion battery can be regenerated without deep separation of Cu and Fe.

Methylammonium lead triiodide (MAPbI3) perovskite has attracted broad interest for solar cells, light‐emitting diodes, and so forth. Experiments have captured that the alternative coexistence of polar and nonpolar domains in MAPbI3 can be switched by photons and phonons. Therefore, it is urgent to clarify the interplay among the crystal space group, polarity, ferroic properties, and switching mechanisms for MAPbI3. Herein, we perform a statistical synthesis on ferroelectric and anti‐ferroelectric features for tetragonal MAPbI3 perovskite. The polar and nonpolar domains are ferroelectric with the I4cm space group and anti‐ferroelectric with the I4/mcm space group, respectively. The domain wall (DW) separating nonpolar and polar regions is charged. Combining the effects of the electric properties of ferroic domains and the charged DWs, novel switching mechanisms are proposed in which photons and phonons drive alternations between ferroelectric and anti‐ferroelectric domains, which provide a reasonable approach to clarify the ambiguous understanding of ferroic behavior for MAPbI3 perovskite. This review establishes the inherent relation among space group, polarity, ferroic properties, and switching mechanisms in tetragonal MAPbI3 perovskite. More important from this review is that, ferroic domain wall engineering including electric potential, organic orientation, and so forth, would be an efficient way to tune photoelectric and thermomechanical performances of MAPbI3 perovskite.

LiMn2O4/graphite batteries using LiF additive were fabricated and their electrochemical performance including discharge, cycling and storage performances were tested and compared with LiF-free LiMnEO4/graphite batteries. The LiMnEO4/graphite battery with LiF added shows better capacity （107.5 mAh/g）, cycling performance （capacity retention ratio of 93% after 100 cycles）, and capacity recovery ratio （98.1%） than the LiF-free battery. The improvement in electrochemical performance of the LiF-added LiMnEO4/graphite battery was due to the fact that LiF can restrain the dissolution of Mn from the spinel LiMn2O4 cathode into the electrolyte, leading to a smaller resistance and polariza- tion.

Spinel LiMn 2 O 4 -based lithium-ion batteries are widely applied in electric two-wheeler and low-speed vehicles due to their low cost and low toxicity. Nevertheless, the Mn deposition at the anode originated from Mn dissolution of LiMn 2 O 4 causes a poor elevated temperature cycle life of graphite/LiMn 2 O 4 batteries. Herein, a graphite/LiFePO 4 cell with specific Mn 2+ added in the electrolyte is provided as an efficient evaluation method to research Mn 2+ deposition. Besides, an effective strategy by adding a ligand hexamethylenetetramine (HMTA) as an electrolyte additive is proposed to prevent Mn 2+ depositing. HMTA effectively “locks in” Mn 2+ through strong coordination, as confirmed by Raman spectroscopy and density functional theory (DFT) calculations. Moreover, the CV and XPS results indicate that the adsorption of HMTA is able to significantly inhibit side reactions at the anode/electrolyte interface. By adopting this strategy, the capacity retention of graphite/LiMn 2 O 4 cell is enhanced from 68.9% to 79.0% at 0.5 C after 100 cycles under 60 °C when adding 0.5% HMTA additive into the blank electrolyte. This work provides a new insight into revealing the mechanism of Mn 2+ regulation by introducing HMTA and improving the electrochemical performance of graphite/LiMn 2 O 4 batteries at elevated temperature.

All-solid-state lithium batteries (ASSLBs) are regarded as the most promising alternative to traditional liquid lithium-ion batteries due to their high-energy density and excellent safety. As an important part of ASSLBs, composite polymer electrolytes (CPEs) with excellent comprehensive performance have attracted wide attention from researchers. Herein, a series of CPEs were prepared by employing Li 6.4 Ga 0.2 La 3 Zr 2 O 12 (LGLZO) submicron particles with cubic phase as fillers in polyethylene oxide (PEO) matrix. The tape-casting method was employed to prepare PEO-LiTFSI-x% LGLZO (CPE-x, where x  = 0–80). In these CPE-x, the CPE-40 exhibits elevated ionic conductivity (6.20 × 10 −5 S cm −1 at 20 °C and 1.88 × 10 −4 S cm −1 at 60 °C), attractive Li + transference number (0.31 at 60 °C), low activation energy barrier of lithium-ion migration, wide electrochemical window, and high critical current density of 1.3 mA cm −2 . Furthermore, the LiFePO 4 | CPE-40 | Li batteries deliver outstanding cycle performance (capacity retention of 85.43% after 225 cycles at 0.2C and 60 °C) and rate performance. These results show that the PEO-base solid-state electrolytes filled with submicron LGLZO particles possess a broad application prospect.

The Fukang Sag in the Junggar Basin is an important petroleum exploration and exploitation region. However, the geothermal regime and tectono-thermal evolution of the Fukang Sag, which control its hydrocarbon generation and conservation, are still controversial. This study involved a systematic analysis of the present-day geothermal gradient, heat flow, and thermal history of the Fukang Sag for better further exploration. According to the well log data and well-testing temperature data, we calculated that the geothermal gradient of the Fukang Sag ranges from 16.6 °C/km to 29.6 °C/km, with an average of 20.8 °C/km, and the heat flow ranges from 34.6 mWm−2 to 64.3 mWm−2, with an average of 44.6 mWm−2. Due to the basement relief, they decrease from northeast to southwest. The weight averages of the single-grain apatite (U-Th)/He ages of the core samples are 1.3–85.2 Ma, and their apatite fission track ages range from 50.9 Ma to 193.8 Ma. The thermal modeling results revealed that the Fukang Sag experienced late Permian, late Jurassic, and late Cretaceous cooling events (although the timing and magnitude of these events varied among the samples), which were related to the continuous compression of the Junggar Basin. In addition, basin modeling indicated that the heat flow of the Fukang Sag decreased from 80 mWm−2 in the Carboniferous to the current value of 44.6 mWm−2. The Fukang Sag’s edge exhibits prolific hydrocarbon generation in the Carboniferous–Permian source rocks, while the Jurassic source rocks within the sag also undergo abundant hydrocarbon generation. This study provides new insights into the present-day geothermal field and tectono-thermal evolutionary history of the Fukang Sag, which are significant in terms of regional tectonic evolution and oil and gas resource assessment.