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Transition metal oxides are promising anode materials for rechargeable lithium-ion batteries (LIBs) because of their high theoretical specific capacity. Li2MoO4 (LMO) has a high specific capacity due to its variable oxidation state and alloying reaction, but the low conductivity and large volume expansion significantly impede its practical applications. To overcome these challenges, here we propose a nickel-doping strategy to prepare Li2NixMo1−xO4 (LNMO) as an anode of LIBs by doping Li2MoO4 with Ni2+ ions using a sol–gel process. The Ni-doping can not only help minimize the path length for ion and electron transport, thus enhancing electron transmission or conductivity, but also offers a mechanical cushion against volume expansion and contraction amid regular insertion and removal of Li+. As a result, the as-developed LNMO anode exhibits a higher reversible charge/discharge specific capacity than LMO, in addition to excellent cycling stability. The Li2Ni0.05Mo0.95O4 anode exhibits a stable lithium storage capacity of 487.2 mA h g−1, much higher than the 210.9 mA h g−1 for the LMO anode after 100 charge/discharge cycles at a current density of 100 mA g−1. This work offers a facile yet effective approach to creating high-performance Li2MoO4 anode materials, thus promoting their real-world application in rechargeable LIBs. [ABSTRACT FROM AUTHOR]

This article discusses the coordinated control problem of multiple high-speed trains operating under the virtual coupling mode. The study proposes a novel distributed model predictive control (DMPC) algorithm to address safety inter-train distance constraints and other independent constraints affecting train dynamics. The algorithm decomposes the centralized control problem into a sequence of local problems and considers potential hypothetical control policies among neighboring trains. The feasibility and effectiveness of the proposed algorithm are confirmed through theoretical analysis and numerical experiments. The article also discusses the modeling and control of high-speed trains operating under the virtual coupling mode, with a focus on designing control strategies that ensure speed consensus, maintain inter-train distances, and avoid collisions. A distributed model predictive control framework is proposed to handle the multiple constraints involved in the cooperative operation of the trains. The article presents a distributed model predictive control problem for coordinating the operation of high-speed trains in a virtual coupling mode. The problem is solved using a distributed serial iterative architecture to reduce communication requirements and increase robustness. The problem is converted into a series of smaller optimization problems that can be solved cooperatively based on information from adjacent trains. The feasibility of the optimization problems is proven, and the proposed approach is more practical for implementation. The article discusses a distributed control protocol for high-speed trains operating under the virtual coupling mode, aiming to achieve speed consensus and maintain safe distances between trains. The effectiveness of the control protocol is supported by a theorem and proof, and numerical simulations comparing the proposed protocol with other control policies are conducted. The simulations consider parameters [Extracted from the article]

Abstract: To guarantee the position and velocity tracking performance of high speed trains (HSTs) with actuator faults, a composite control algorithm consisting of the disturbance‐observer‐based control (DOBC) and ℋ ∞ control is proposed. Based on the multiple point‐mass model, the dynamics of HSTs is established by a cascade of carriages which are connected by flexible couplers, during the procedure of which, the running resistance, actuator faults and multiple disturbances are taken into account. The multiple disturbances are composed of two parts, one of which is the ramp resistance due to the track slope, the other is unknown gusts which can be modeled as a harmonic disturbance with time‐varying frequency. The unknown gusts is estimated and rejected via the DOBC methodology, meanwhile, the running resistance and the ramp resistance are attenuated by the ℋ ∞ control methodology. According to the Lyapunov stability analysis and LMI‐based algorithms, main results are derived such that the closed‐loop system is asymptotically stable and the desired performance can be guaranteed. Compared with the numeral simulation results with the single ℋ ∞ control method, it is demonstrated that the proposed control methodology is more effective and the system has a higher precision of position and velocity tracking. [ABSTRACT FROM AUTHOR]

High-speed trains are susceptible to unexpected events such as strong winds and equipment failures, which can result in deviations from the scheduled timetable. As the density of traffic increases, these delays can quickly spread to other trains, eventually leading to conflicts in the timetable. To ensure the efficiency of high-speed railways, quickly resolving potential conflicts and generating appropriate rescheduling schemes are essential. The existing hierarchical structure of train control and online rescheduling tends to be inefficient in terms of information communication and can even lead to unfeasible rescheduled timetables and trajectories. To address these issues, an integrated structure of timetable rescheduling and train trajectory optimization is proposed by introducing the train minimum running time into the process of timetable rescheduling and using the adjusted running time as the objective of trajectory optimization. The integration model is formulated by considering the constraints of timetable rescheduling such as the maximum number of trains overtaking trains, platforms at stations, and the priority of the train, as well as the constraints of trajectory optimization. A deep reinforcement learning (DRL)-based approach is proposed to solve the problem. Numerical experiments are conducted on a segment of the Beijing-Shanghai high-speed railway line, using adapted data to demonstrate the effectiveness of the proposed method in rescheduling timetables and optimizing train trajectories. The results show that the integrated rescheduled timetable and the optimized train trajectory can be generated simultaneously and the computation time exhibits a linear increase with respect to the size of the problem.

The hunt for a higher power storage, relatively inexpensive, non-polluting battery technology is currently a pressing issue because of the rapid growth of the worldwide economic and the progressively significant environmental pollution. Among the possible nanomaterials for rechargeable batteries that can have heteroatoms applied to it in order to improve its electrochemical behavior is Li x Ti y (PO 4 ) 3 . Carbon-coated Mn-doped Li 2 Mn 0.1 Ti 1.9 (PO 4 ) 3 materials was synthesized by spray drying method. The material was characterized by XRD, SEM, TEM, BET, TGA et al. Crystal data refinement results by Rietveld method showed that the symmetry space group is Pbcn.The lattice parameters of Li 2 Mn 0.1 Ti 1.9 (PO 4 ) 3 are a = 11.9372 Å, b = 8.5409 Å, c = 8.5979 Å, α = β = γ = 90°, V = 876.59 Å 3 and Z = 4). Rietveld refinement was performed, and the confidence factors are Rwp = 11.79%, Rp = 9.14%, and χ 2 = 1.425. It was exhibited that LMTP0.1/CA-700 material has good crystallinity. Testing the cells with LAND test procedure (200 mA/g current density for 200 cycles), the LMTP0.1/CA-700 material has a discharge specific capacity of about 65 mAh/g. The capacity decayed by only 3% during the cycle. It has some potential application values as cathode of lithium ion battery in the future., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Sun, Hu, Bai, Mao and Song.)

Objective: To evaluate the Expression and correlation of cyclooxygenase-2 (COX-2) and vascular endothelial growth factor receptor (VEGF) in nasopharyngeal carcinoma., Method: In this study, expression levels of COX-2, VEGF were examined in 58 patients with nasopharyngeal carcinoma and 38 patients with inflammation in nasopharyngeal mucosa by immunohistochemistry method., Result: The expression of COX-2, VEGF were higher in nasopharyngeal carcinoma than those in nasopharyngeal mucosa (P < 0.05), and they had some correlation with the invasion and lymphatic metastasis and with the clinical stage of nasopharyngeal carcinoma (P < 0.05). The expression of COX-2 was positively correlated with that of VEGF (P < 0.05)., Conclusion: The coexpression of COX-2 and VEGF may play animportant role in the carcinogenesis and development of nasopharyngeal carcinoma, and they may prom (see text) lymph node metastasis of nasopharyngeal carcinoma.

Objective: To discuss the expression and correlation of COX2 and LMP1 in NPC., Method: Fifty-three nasopharyngeal biopsy specimens of NPC patients who had been diagnosed definitely with pathology in our department from 2000 to 2005, and 8 nasopharyngeal biopsy specimens of chronic nasopharyngitis patients were collected. The expression of COX2, LMP1 were detected with streptavidin peroxidase immunohistochemistry staining. All the datas were analyzed with SPSS 12.0., Result: The positive expression rate of COX2 was 71.70% (38/53), and that of LMP1 was 66.04% (35/53) of Nasopharyngeal carcinoma tissue. The higher expression rate was detected in neck lymph nodes metastasis group of nasopharyngeal carcinoma (P<0.05). While the expression rate of COX2, LMP1 was no significant relation with age, gender, clinical stage and pathological classification (P>0.05). The expression of COX2 and LMP1 showed positive correlation (gamma = 0.797, P<0.01)., Conclusion: COX2 and LMP1 were highly expressed in nasopharyngeal carcinoma cells. The expressions of COX2 and LMP1 was significantly associated with neck lymph nodes metastasis, and was none-significant relation with age, gender, clinical stage and pathological classification. The expression of LMP1 showed a significant positive correlation with that of COX2. LMP1 could enhance NPC neck lymph nodes metastasis by up-regulating the expression of COX2.