Low Mass X-ray Binary As the Progenitor of PSR J1713+0747

We have calculated the evolution of low-mass X-ray binaries that leads to the formation of the binary radio pulsars like PSR J1713+0747. We show that the mass transfer is most likely to be nonconservative, due to unstable disk accretion, to account for the mass of PSR J1713+0747, which is close to its initial value. We assume that part of the lost material from the binary may form a circumbinary disk, and find that it can significantly influence the mass transfer processes. We briefly discuss the implications of the circumbinary disks on the evolution of low-mass X-ray binaries and the formation of low-mass binary pulsars.Comment: 8 pages, 4 figures, accepted for publication in PAS

The control strength quantification analysis of outer pendulum rod for double inverted pendulum

Due to the complexity of the dynamics characteristics of an inverted pendulum, and the problem that the linearization analyze method cannot satisfy the controlling requirement, a nonlinear dynamics analyze method was proposed. Through decoupling the dynamics model of a double inverted pendulum, the outer pendulum rod motion equation was derived. And then, aiming at the control strength function of outer pendulum rod, the qualitative and quantitative relationship between spatial position of pendulum rod and the control strength of outer rod, and the quantification relationship between dynamics parameters and the control strength of outer rod were separately analyzed. And the simulation verified the correctness of the analysis

A thermal behavior of low-substituted hydroxyethyl cellulose and cellulose solutions in NaOH-water

The articles belonging to the special issue are open access, all published articles are freely available online.International audienceHydroxyethyl cellulose (HEC) with low molar substitution has better solubility in 8%NaOH-water solution than pure cellulose. The thermal behavior of ternary HEC/NaOH/water mixtures was investigated by DSC, and the results are compared with those of cellulose/NaOH/water solutions, aiming at providing better understanding about cellulose dissolution mechanism in NaOH-water. At low polymer concentrations and below 0°C, HEC and cellulose solutions exhibit a similar thermal behavior with ice, eutectic and/or melting and recrystallization peaks, showing that the overall interactions between NaOH, water and cellulose or HEC are identical. However, when the concentration increases above 2%, the eutectic peak of HEC solutions disappeared, leaving only the ice peak, which is different from previous results for cellulose where the disappearance of the eutectic peak was related to the maximum solubility of cellulose (around 8 wt%). This implies that the dissolution behavior of HEC in NaOH solution is changed due to possible changes of chain flexibility and/or increased attractions to water caused by the hydrophilic hydroxyethyl groups. The melting and recrystallization peaks visible only at low concentrations of HEC or cellulose in solution also support the conclusion that dissolution of cellulose and HEC at low concentrations bears features which are not yet understood

Electrochemical Performance of Nanorod-like (La, Zr) Co-Doped Li-rich Li₁.₂Ni₀.₂Mn₀.₆O₂ OF ACCESS Cathodes for Use in Lithium-Ion Batteries

A lithium-rich layered structure in lithium-ion batteries (LIBs) has attracted much attention due to its high capacity of over 250 mAhg⁻¹ after activation. This could satisfy the requirements of next-generation energy-storage devices. However, a spinel-like impurity phase that forms from the pristine layered structure during cycling is considered to be harmful to the structure stability and Li⁺ mobility, resulting in undesired electrochemical performance. In this study, nanorod-like Li₁.₂Ni₀.₂Mn₀.₆O₂ with a three-dimensional architecture was synthesized by evaporative-crystallization with as-prepared nano-MnO₂ as a hard template. The structure stability and Li⁺ mobility of the nanorod-like Li₁.₂Ni₀.₂Mn₀.₆O₂ was improved by the addition of an appropriate molar ratios of (La, Zr) co-dopants. This combination exhibited outstanding capacity retention of 80.9% with a stable discharge capacity of 102 mAh g⁻¹ after 300 cycles under a high current density of 1000 mAg⁻¹ (corresponding to S C). This study suggests that the use of a multi-prong strategy that combines morphology control and co-doping should be an effective method for improving the high-rate performance of Li-rich materials

LiNi₀.₅Mn₁.₅O₄ Cathode Materials Co-Doped with La³⁺ and S²⁻ for Use in Lithium-Ion Batteries

Spherical LiNi₀.₅Mn₁.₅O₄ particles co-doped with lanthanum (La) and sulfur (S) were synthesized by a facile co-precipitation assisted solid-state annealing method with stable oxysulfide La₂O₂S (x = 0, 0.3, 0.5, 0.7, 1.0, and 1.2 at%) as a dopant. The prepared composite materials exhibited a slight shrinkage of lattice parameters without any impurity phase under x <= 0.7 at%, and the Ni/Mn disordered arrangement in the spinel lattice increased with an increase in the ratio of dopants, as confirmed by X-ray diffraction and Raman spectroscopy. X-ray photoelectron spectroscopy and electrochemical measurements also clearly indicated that the residual Mn³⁺ in the cubic lattice could be effectively eliminated with the use of La₂O₂S dopants. The composite materials showed outstanding rate and cycling performance compared with those of the pristine material. Specifically, the material doped with 0.5 at% La₂O₂S showed a high reversible capacity of 115.9 mAh g⁻¹ at 10 C, and a remarkable cycling performance of 109.2 mAh g⁻¹ even after 200 cycles. All of these extraordinary performances were attributed to the synergistic effects of La and S in the spinel structure, which induce a suitable pathway for lithium ion and a robust architecture during the electrochemical assessment

Large-Signal Stability Criteria in DC Power Grids with Distributed-Controlled Converters and Constant Power Loads

The increasing adoption of power electronic devices may lead to large disturbance and destabilization of future power systems. However, stability criteria are still an unsolved puzzle, since traditional small-signal stability analysis is not applicable to power electronics-enabled power systems when a large disturbance occurs, such as a fault, a pulse power load, or load switching. To address this issue, this paper presents for the first time the rigorous derivation of the sufficient criteria for large-signal stability in DC microgrids with distributed-controlled DC-DC power converters. A novel type of closed-loop converter controllers is designed and considered. Moreover, this paper is the first to prove that the well-known and frequently cited Brayton-Moser mixed potential theory (published in 1964) is incomplete. Case studies are carried out to illustrate the defects of Brayton-Moser mixed potential theory and verify the effectiveness of the proposed novel stability criteria

Academic Activities Transaction Extraction Based on Deep Belief Network

Extracting information about academic activity transactions from unstructured documents is a key problem in the analysis of academic behaviors of researchers. The academic activities transaction includes five elements: person, activities, objects, attributes, and time phrases. The traditional method of information extraction is to extract shallow text features and then to recognize advanced features from text with supervision. Since the information processing of different levels is completed in steps, the error generated from various steps will be accumulated and affect the accuracy of final results. However, because Deep Belief Network (DBN) model has the ability to automatically unsupervise learning of the advanced features from shallow text features, the model is employed to extract the academic activities transaction. In addition, we use character-based feature to describe the raw features of named entities of academic activity, so as to improve the accuracy of named entity recognition. In this paper, the accuracy of the academic activities extraction is compared by using character-based feature vector and word-based feature vector to express the text features, respectively, and with the traditional text information extraction based on Conditional Random Fields. The results show that DBN model is more effective for the extraction of academic activities transaction information