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The anterior cruciate ligament is one of the important tissues to maintain the stability of the human knee joint, but it is difficult for this ligament to self-heal after injury. Consequently, transplantation of artificial ligaments (ALs) has gained widespread attention as an important alternative treatment method in recent years. However, accurately predicting the intricate mechanical properties of ALs remains a formidable challenge, particularly when employing theoretical frameworks such as braiding theory. This obstacle presents a significant impediment to achieving optimal AL design. Therefore, in this study, a high-precision machine learning model based on an artificial neural network was developed to rapidly and accurately predict the mechanical properties of ALs. The results showed that the proposed model achieved a reduction of 45.22% and 50.17% in the normalized root mean square error on the testing set when compared to traditional machine learning models (Random Forest and Support Vector Machine), demonstrating its higher accuracy. In addition, the design of ALs with desired mechanical properties was achieved by optimizing the braiding parameters, and its effectiveness was verified through experiments. The mechanical properties of the prepared ALs were able to fully meet the desired targets and were at least 2% higher. Finally, the influence weights of different braiding parameters on the mechanical properties of ALs were analyzed by feature importance. [ABSTRACT FROM AUTHOR]

Cobalt-free perovskite oxides NdBaCu 2 O 5+δ (NBCO) and NdBa 0.5 Sr 0.5 Cu 2 O 5+δ (NBSCO) has been investigated as cathode materials in intermediate-temperature solid fuel cells (IT-SOFCs). The crystal structure, thermal expansion, electrical conductivity and electrochemical properties have been characterized by X-ray diffraction (XRD), dilatometer, four-probe dc method, electrochemical impedance spectroscopy (EIS) and cathodic polarization examinations. The average thermal expansion coefficients (TEC) values of NBCO and NBSCO are 13.0 × 10 −6 /°C and 14.5 × 10 −6 /°C, which are more desirable on combining with the electrolytes than cobalt-based cathodes. The partly substitution of Sr on B-site increases the electron hole concentration and improves the conductivity. The polarization resistances values of NBSCO are 0.205 Ωcm 2 , 0.200 Ωcm 2 and 0.135 Ωcm 2 , whereas the polarization resistances values of NBCO are 8.61 Ωcm 2 , 3.18 Ωcm 2 and 0.83 Ωcm 2 at 600 °C, 700 °C and 800 °C, respectively. The improved electrochemical performance of NBSCO should be ascribed to the higher conductivity as well as the improved oxygen adsorption/desorption and oxygen ions diffusion processes. [ABSTRACT FROM AUTHOR]

In order to simplify the template method for the synthesis of cathode materials for lithium ion batteries, a facile template method using plant stalks as bio-templates has been introduced. Based on this method, LiNi 0.5 Mn 1.5 O 4 spinel with a significantly improved electrochemical performance has been synthesized using corn stalk as a template. X-ray diffraction (XRD), Fourier transform infrared pectroscopy (FTIR) and scanning electron microscope (SEM) have been used to investigate the phase composition and micro-morphologies of the products. Charge-discharge measurements in lithium cells, cyclic voltammetry (CV) and Electrochemical impedance spectroscopy (EIS) have been used to study the electrochemical performance of the products. The results indicate that the templated product exhibits higher crystallinity than that of non-templated product. Both of the templated product and the non-templated product are combination of the ordered space group P4 3 32 and the disordered Fd-3 m. The specific BET surface area of the templated product is about twice larger than that of the non-templated product. Moreover, the electrochemical performances of the templated product including specific capacity, cycling stability and rate capability are significantly improved as compared with the non-templated product, due to its higher crystallinity, larger Li + diffusion coefficient and lower charge transfer resistance. [ABSTRACT FROM AUTHOR]

High-voltage LiNi0.5Mn1.5O4 spinels were synthesized by a low temperature solution combustion method at 400°C, 600°C and 800°C for 3h. The phase composition, structural disordering, micro-morphologies and electrochemical properties of the products were investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and constant current charge–discharge test. XRD analysis indicated that single phase LiNi0.5Mn1.5O4 powders with disordered Fd-3m structures were obtained by the method at 400°C, 600°C and 800°C. The crystallinity increased with increasing preparation temperatures. XRD and FTIR data indicated that the degree of structural disordering in the product prepared at 800°C was the largest and in the product prepared at 600°C was the least. SEM investigation demonstrated that the particle size and the crystal perfection of the products were increased with increasing temperatures. The particles of the product prepared at 600°C with ~200nm in size are well developed and homogeneously distributed. Charge/discharge curves and cycling performance tests at different current density indicated that the product prepared at 600°C had the largest specific capacity and the best cycling performance, due to its high purity, high crystallinity, small particle size as well as moderate amount of Mn3+ ions. [ABSTRACT FROM AUTHOR]

Abstract: In the present study the evaporative precipitation into aqueous solution (EPAS) process and the high homogenization press (HPH) process were compared to evaluate their feasibility to form a chemically stable quercetin nanosuspension. The particle size and Zeta potential of the EPAS nanosuspension were similar to those of the HPH nanosuspension. Differences in results of differential scanning calorimetery and X-ray measures were observed between the two processes. The crystalline-to-amorphous phase transition was shown in the profile of EPAS dried powder. On the contrary the initial crystalline state of drug was maintained throughout the HPH process. Dissolution test results indicated that the EPAS process showed a higher improvement in the drug solubility and dissolution rate than the HPH process. At last the High performance liquid chromatography (HPLC) analysis proved the superiority of both nanosuspensions over QCT solution formulation for the chemical and photo-stability. As a result, it can be concluded that the EPAS and HPH techniques were feasible to prepare a chemically stable QCT nanosuspension with significantly enhanced dissolution rate. [ABSTRACT FROM AUTHOR]

Abstract: A porous carbon was prepared using halloysite as a template and sucrose as carbon source by means of template method. Nitrogen adsorption analysis showed that the obtained porous carbon material possess a wide pore size distribution and a large pore volume, especially in the range of mesopores. The application of the resultant carbon for electrodes of electric double layers capacitor (EDLC) in organic LiPF6/PE+CE electrolyte indicated that the specific capacitance, as high as 232F/g at a current density of 0.05mA/cm2, was larger than for commercially activated carbons. Cyclic voltammetry (CV) also showed that the performance of templated carbon in 1mol/l aqueous solution of H2SO4 was better at a large scan rate than for the commercial activated carbons. [Copyright &y& Elsevier]

Degradation behavior is a key fundamental topic in the field of silk-based biomaterials. In this study, genipin-crosslinked silk fibroin films with varying crosslinking degrees were generated to investigate the effect of the crosslinking degree on the degradation behavior. Higher crosslinking degrees resulted in increased inter-intramolecular network crosslinking density through covalent bonds, which restricted enzymatic attacks and the release of enzyme-degraded polypeptides from silk fibroin molecular networks, providing greater resistance to enzyme degradation. Furthermore, genipin crosslinking induced the conformational transition from random coil to β-sheet due to the structural rearrangement of the chains to form covalent bonds. High β-sheet content contributes to a more crystalline structure that also enhances resistance to enzyme degradation. Consequently, changing the crosslinking degree had a substantial impact on the degradation rate. The high-crosslinking films (with a crosslinking degree greater than 90%) showed a similar degradability to 75% ethanol-treated films, which were barely degraded by collagenase IA and subcutaneous implantation in SD rats. However, decreasing the crosslinking degree from 90% to 78% significantly increased the degradation ratio from 4 wt% to 18 wt% after 28 days in vivo degradation, respectively. In particular, the degradability was strongly correlated to the crosslinking degree in the low-crosslinking (lower than 90%) films. These results reveal that the crosslinking process can efficiently control molecular structures and regulate the crystallization of silk fibroin materials, in turn providing control of the degradation rate. [ABSTRACT FROM AUTHOR]

SmBaCo 2−x−y Mn x Mg y O 5+δ (x = 0.5, 1, 1.5 and y = 0.05, 0.1) samples are synthesized by sol-gel method. The influence of different substitution of Mn and Mg for Co on crystal structures, thermal expansion coefficient (TEC), electrical conductivities and electrochemical performances have been investigated. The generation of the secondary phase BaMnO 3 is suppressed with Mg 2+ increasing. Demonstrated by temperature-dependent X-ray diffraction from 25 °C to 700 °C, the structure of SmBaCo 0.4 Mn 1.5 Mg 0.1 O 5+δ in high temperature is stable. The TEC of SmBaCo 1.45 Mn 0.5 Mg 0.05 O 5+δ , SmBaCo 0.95 MnMg 0.05 O 5+δ , SmBaCo 0.45 Mn 1.5 Mg 0.05 O 5+δ and SmBaCo 0.4 Mn 1.5 Mg 0.1 O 5+δ are 15.77 × 10 −6 K −1 , 16.20 × 10 −6 K −1 , 12.19 × 10 −6 K −1 and 12.58 × 10 −6 K −1 , respectively, which are much lower than those of cobalt-based layered perovskites and more compatible with the thermal expansion of SDC electrolyte. Although the electrochemical performances of SmBaCo 2−x−y Mn x Mg y O 5+δ (x = 0.5, 1, 1.5 and y = 0.05, 0.1) decrease slightly with Mn increasing, the polarization resistances of the SmBaCo 1.45 Mn 0.5 Mg 0.05 O 5+δ and SmBaCo 0.4 Mn 1.5 Mg 0.1 O 5+δ are 0.17 Ω cm 2 and 0.30 Ω cm 2 at 800 °C, respectively, which can meet the electrochemical performance requirements of cathode materials. Among the samples, the SmBaCo 1.45 Mn 0.5 Mg 0.05 O 5+δ and SmBaCo 0.4 Mn 1.5 Mg 0.1 O 5+δ show better tradeoff properties between TEC and electrochemical performance as cathode materials for IT-SOFCs. [ABSTRACT FROM AUTHOR]