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The key to battery management systems (BMS) is an accurate and real-time prediction on State of Charge (SOC) of the power battery. The methods of estimating SOC of power battery were analyzed. The gray neural network model was introduced into the field of SOC estimation. The model is used to establish the relationship of SOC, discharge current and rebound voltage. The model can be used to estimate SOC of battery on line by detecting the values of rebound voltage and discharge current during the discharge process. The model of SOC estimation is proved feasible by comparing the experimental data with calculated data. [ABSTRACT FROM AUTHOR]

Highlights • All kinds of A-type tracks were classified into three types based on the conditions of vapor model proposed by Dominguez (2009). • A simple deceleration mechanism was confirmed by the data fitted well with the regular data of the terminal A-β type track. • Thermal effects happened around and along track was observed by scanning electron microscopy. Abstract As an attractive collector medium for hypervelocity particles, SiO 2 aerogel has been deployed on outer space missions. Aiming at quantifying the complicated relationship between the penetration track and the residual grains, many attempts have been made on hypervelocity experiments and models. However, models were difficult to accord strictly well with experimental data attributed to many uncertainties including thermal effects, aerogel accretions and projectile ablation during the penetration. In this paper, impact experiments were conducted at various density silica aerogels (50∼120 kg·m−3) with regular soda-lime glass beads as projectiles. Varying degrees of thermal effects happened around and along track was observed by scanning electron microscopy. That energy distribution in the track released by hypervelocity projectile has a decreasing change. The regular data of the terminal A-β type track (the track with combined features) was found according to A-type tracks classification based on the conditions of vapor model (Domínguez, 2009). Just considering for projectile overcoming the crushing strength with uniform deceleration, the simple mechanism was confirmed by the data fitted well with the snowplow model (Domínguez et al., 2004). The result after tracks classification is due to the terminal track with few thermal effects and aerogel accretions. In addition, other two types of tracks formation processes were discussed. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

The lithium ion battery is considered as the experimental object, and its discharge characteristics are studied. A model of the battery in different charge-states is established by a tool of neural network while battery's rebound voltage, temperature and load are set as input parameters. The validity of the model is tested based on the experimental data. The accuracy, adaptability and stability of the SOC in this model is validated in a variety of the working conditions, and the accuracy of the model is demonstrated to be higher than 5%. [ABSTRACT FROM AUTHOR]

To study the ignition characteristics of semiconductor bridges (SCB) for automobile airbag igniters, a model was proposed to compute the electrical characteristics of SCB based on the structural characteristics, resistance properties, and the working process of the bridge. Numerical simulation was conducted to analyze the voltage and current trends at two ends of bridges with various geometric dimensions and those with identical geometric dimensions and oxide layers of different thicknesses. Voltage-current curves for bridges of three different dimensions were obtained through numerical simulation. Bridges of larger geometric dimensions were found to require higher voltage to reach the melting point, which means higher energy input is required. [ABSTRACT FROM AUTHOR]

A Semiconductor Bridge (SCB) explosive initiator has many advantages such as shorter action time, better ignition consistency and higher reliability. The development of a SCB has traditionally been guided by an experimental approach. Experiments conducted worldwide show that the melting and vaporization of a SCB when heated by an electrical current is a very complex physical process. In this process, the bridge goes through multi-phase changes, i.e., in order solid, liquid, gaseous and plasma-state. This paper discusses the numerical simulation of the SCB working process when driven with a short low-energy pulse. In an effort to elucidate the behaviors of the SCB working process, the temperature distribution before the SCB melting and SCB discharge are presented. The basic semiconductor equations and heat transfer equation are described to evaluate the temperature distribution in the SCB. The results are obtained from finite-difference implementations. The edge gasification effect of SCB is proved by the curve of temperature distribution, and the double temperature characteristic of SCB is shown. Finally, a SCB discharge model is established. The result shows that the bigger the external voltage, the longer is the discharge time. [ABSTRACT FROM PUBLISHER]

The semiconductor bridge (SCB) is a heavily n-doped semiconductor. The SCB device has advantages for reducing voltage and energy requirements compared with a conventional device. It also has very excellent safety. When driven with a short low-energy pulse, the SCB creates hot plasma to ignite energetic materials. The hot plasma permeates the energetic materials and deposits its latent heat of fusion to the grains, thereby heating the granular surfaces to energy states required for self-sustained reaction. The behavior of the SCB can be facilitated through the simulation of the electrical components. The resistance of the SCB is a key parameter during the process of producing the plasma. The dynamic resistance of a heavily doped semiconductor resistor was evaluated by observing the electrical mobility and conductivity of the resistor as a function of temperature covering the range from room temperature to the plasma temperature. In an effort to elucidate the dynamic resistance of the SCB, current was forced to flow through the bridge with an initial resistance of 1 \Omega. The energy stored in a 25- \mu\F capacitor was used to activate the plasma. Two peaks in the voltage–time curve were typically observed. Time histories of the resistance and voltage show the special features of the resistor. It appears that the resistance increases initially before the intrinsic temperature and then decreases due to negative resistance behavior, and then, the resistor is melted and vaporized to generate plasma. [ABSTRACT FROM PUBLISHER]

This paper focuses on the trajectory tracking issue of the pneumatic artificial muscle (PAM) exoskeleton system. First of all, a new type of the PAM elbow exoskeleton was introduced to assist wearers in elbow flexion/extension movement. Moreover, a model-free adaptive control approach was combined with the prescribed performance control to ensure the tracking errors to be converged to the predefined requirements. Meanwhile, to suffer the influence of the unknown external disturbance on the exoskeleton, a terminal sliding mode control was adopted to reduce the tracking errors. From a theoretical perspective, the stability of the proposed controller can be proved by Lyapunov synthesis. After two sets of experiments, the proposed control method can further improve the tracking accuracy in the PAM elbow exoskeleton, compared with the other three model-free adaptive control methods. Simultaneously, the maximum absolute value of the tracking errors never exceeded the designed boundary. [ABSTRACT FROM AUTHOR]

As an attractive collector medium for hypervelocity particles, combined with outstanding physical properties and suitable compositional characteristics, SiO2 aerogel has been deployed on outer space missions and laser shock-loaded collection experiments. In this paper, impact experiments were conducted to understand the penetration process of irregular grains, irregular Al2O3 grains with two different sizes and speeds (~110 μm@7 km/s, ~251 μm@2.3 km/s) at various density silica aerogels. By classifying the shapes of projectile residues and tracks, the morphology of tracks was analyzed. It was observed that there were several kinds of typical tracks in the penetration of irregular grains, accompanied by residues with the shapes of near-sphere, polyhedron, streamlined body wedge, and rotator. The rotational behavior was demonstrated by the final status of one flake projectile as direct evidence. In addition, there was no obvious relationship between the track length and experimental parameters, which may be caused by the uncertain interaction between aerogels and irregular particles. In addition, it confirmed the existence of fragmentation, melting situation by observing the shape of the impact entrance hole. At the same time, optical coherence tomography was used to observe the detail of tracks clearly, which provided a method to characterize the tracks nondestructively. [ABSTRACT FROM AUTHOR]

This work aims to develop a numerical-analytical framework within the kinematic approach of limit analysis to assess the stability of non-circular tunnel faces under seepage conditions with tensile strength cut-off from a discretization-based perspective. Considering the overestimation of the tensile strength of the soil by the Mohr-Coulomb criterion, a modification based on the concept of tensile strength cut-off is recommended to reduce or eliminate the tensile strength. A modified 3D rotational discretization-based failure mechanism incorporating the tension cut-off is generated point-to-point starting from a real non-circular tunnel face to model the face failure, where the failure surface on the top intersects more rapidly due to the increasing rupture angle in the tensile regime. The seepage towards the non-circular tunnel face is numerically simulated, and then the numerical seepage field is extracted into the 3D discretization-based failure mechanism. Within the kinematic approach, the seepage effect is introduced from two aspects: pore pressure and seepage force. A hybrid optimization routine is employed to search for the maximum required face pressure. The developed framework is validated by comparisons with numerical fluid-mechanical simulations and previous studies. Afterward, parametric analyses are carried out on different seepage conditions, different face pressure distributions, different soil strengths, and different tension cut-off conditions. The developed framework can give insight into the combined effect of the tension cut-off and seepage on the stability of non-circular tunnel faces under various conditions. [ABSTRACT FROM AUTHOR]

No studies have been focused on the inclusion of organic selenium in formulated feed of abalone when organic minerals are accepted by aquaculture feed industry. This experiment evaluated the effect of organic selenium on the growth, antioxidation, immunity and gene expressions of selenoproteins in abalone. Graded levels of organic selenium were included to the basal diet at 0.00, 0.15, 0.30 and 0.60 ppm providing 157.83, 322.51, 437.59 and 596.59 ug/kg of selenium in the diet. Accordingly, the diets were named as Se‐0.00, Se‐0.15, Se‐0.30 and Se‐0.60 respectively. Results had shown that survival rate, weight gain rate and shell length increase rate were lowest for Se‐0.60 group (p < 0.05). The concentration of selenium in the whole body generally increased with increasing level of dietary organic selenium (p < 0.05). The enzyme activities related to antioxidation increased initially with low levels of dietary selenium and decreased with higher levels, with the highest value in Se‐0.30 group (p < 0.05). The enzyme activities of immunity increased with the addition of dietary selenium. With the increase of dietary selenium, Myostain expression decreased initially and increased afterwards, with lowest value for Se‐0.30 group (p < 0.05). However, the expressions of other genes related to growth, antioxidation and selenoproteins firstly increased and then decreased, with the highest value recorded for Se‐0.15 group. In conclusion, the inclusion rate of 0.15 – 0.30 ppm Se in diet could promote growth, antioxidation, immunity and gene expressions of selenoproteins in abalone; however, excess selenium with 0.60 ppm inclusion lever in diet had toxic effects. [ABSTRACT FROM AUTHOR]

Excessive anxiety is highly prevalent during childhood and adolescence, with detrimental effects on somatic and mental health, and quality of life. Although structural abnormalities in the brain have been found in people with anxiety disorders, whether anxiety affects the brain development of children and adolescents remains unknown. Here, we applied a multivariate approach to two single-site MRI datasets consisting of 733 and 775 participants aged 5–18 years. Using linear support vector regression and cross-validation, brain age is estimated by predicting the chronological age from the features that combine cortical thickness and surface area of 68 brain regions. We found that gray matter can predict the chronological age of children and adolescents with a low mean absolute error. Compared to specific brain network, the whole structural brain measures predicted brain age better. Importantly, adolescents with higher generalized anxiety and those with lower separation anxiety showed lower brain age, indicating a slow development of brain structures. The relationship between anxiety and brain age of youths could also be found in parent-reported separation anxiety. The findings highlight differential effects of different anxiety types on brain structural development and suggest that different types of anxiety during childhood and adolescence should be treated differently. • Cortical thickness and surface area can predict chronological age in adolescence. • Adolescents with higher generalized anxiety show lower brain age. • Adolescents with lower separation anxiety show lower brain age. • Parent-reported separation anxiety is positively associated with brain age. [ABSTRACT FROM AUTHOR]

Background: Beta-ketothiolase deficiency (BKTD) is an autosomal recessive disorder caused by biallelic mutation of ACAT1 that affects both isoleucine catabolism and ketolysis. There is little information available regarding the incidence, newborn screening (NBS), and mutational spectrum of BKTD in China.Results: We collected NBS, biochemical, clinical, and ACAT1 mutation data from 18 provinces or municipalities in China between January 2009 and May 2020, and systematically assessed all available published data from Chinese BKTD patients. A total of 16,088,190 newborns were screened and 14 patients were identified through NBS, with an estimated incidence of 1 per 1 million newborns in China. In total, twenty-nine patients were genetically diagnosed with BKTD, 12 of which were newly identified. Most patients exhibited typical blood acylcarnitine and urinary organic acid profiles. Interestingly, almost all patients (15/16, 94%) showed elevated 3-hydroxybutyrylcarnitine (C4OH) levels. Eighteen patients presented with acute metabolic decompensations and displayed variable clinical symptoms. The acute episodes of nine patients were triggered by infections, diarrhea, or an inflammatory response to vaccination. Approximately two-thirds of patients had favorable outcomes, one showed a developmental delay and three died. Twenty-seven distinct variants were identified in ACAT1, among which five were found to be novel.Conclusion: This study presented the largest series of BKTD cohorts in China. Our results indicated that C4OH is a useful marker for the detection of BKTD. The performance of BKTD NBS could be improved by the addition of C4OH to the current panel of 3-hydroxyisovalerylcarnitine and tiglylcarnitine markers in NBS. The mutational spectrum and molecular profiles of ACAT1 in the Chinese population were expanded with five newly identified variants. [ABSTRACT FROM AUTHOR]

Lignin nanoparticles, emerged as novel porous and functional materials, have attracted great attentions during the past decades. However, use of organic solvents and tedious solvent exchange processes restricted their scale-up production due to the concerns on environmental protection and sustainability. Here, we presented an organic solvent-free strategy to fabricate spherical lignin nanoparticles via soft templating and sol-gel-hydrothermal process in alkaline water media for the first time, in which technical soda lignin was precursor and both PEO−PPO−PEO triblock copolymers (P123) and sodium oleate (SO) acted as soft templates. Assisted by the P123/SO templates, lignin nanospheres (LHCS) were obtained with an average diameter of 190 nm, good dispersity and higher yield (63.29%, wt%). For valorization of prepared samples, lignin nanospheres were coated with tannin acid (TA@LHCS) and introduced into polyvinyl alcohol (PVA) hydrogels for enhancement their mechanical properties. The mechanical strength of the hydrogel was improved by the addition of TA@LHCS, endowing hydrogel with superior stretchability and compressibility. The maximum tensile strength of TA@LHCS enhanced PVA hydrogel reached 303.1 kPa, which was improved by three times. Therefore, this work provided a promising strategy for fabricating lignin nanoparticles via a facile method and broadened their valorizations in enhancing hydrogel strength. • Organic solvent-free method was established to fabricate technical lignin nanospheres. • The nanospheres were assembled via soft templating/hydrothermal alkaline water media. • The nanospheres possessed good dispersity, smaller diameter and higher yield (63.29%). • Mechanical properties of PVA hydrogels was enhanced by introducing lignin nanospheres. [ABSTRACT FROM AUTHOR]

Leaf morphology varies significantly among Brassica juncea. However, little is known regarding the causal gene that controls lobed leaf shape in B. juncea. In our study, the BjRCO gene, which is associated with leaf morphological variation, was cloned from chromosome A10 in B. juncea via BSR-seq. Blast analysis suggested that the BjRCO encodes a HD-Zip I transcription factor, which may serve as a positive regulator of lobed leaf formation in leaf mustard. Interestingly, the lobed leaf genes reported in the related species of Brassica (B. rapa, B. napus, and B. juncea) were located in A10. Phylogenetic analysis showed that BjRCO was also homologous to the lobed leaf gene BoLl reported on chromosome 9 in B. oleracea. In addition, qRT-PCR results showed that the expression levels of the BjRCO gene were higher expressed in the inner small lobed leaves than in the little sawtooth-like leaves (LSL). These results of this study indicate that the BjRCO gene is related to lobed leaf formation in B. juncea. These findings help to establish a solid foundation for future research investigating the molecular mechanism governing lobed leaf formation in B. juncea. [ABSTRACT FROM AUTHOR]

This trial was conducted to investigate the effect of mannose oligosaccharides (MOS) on the growth performance, antioxidation, immunity and disease resistance of Vibro Parahemolyticus in juvenile abalone Haliotis discus hannai Ino. Four formulated diets were produced to contain 0.00 g/kg, 0.40 g/kg, 0.80 g/kg and 1.60 g/kg Actigen®, with functional ingredients of MOS, respectively. Accordingly, the experimental diets were named as A0, A4, A8 and A16. After 120-days feeding trial, the best growth performance was observed in A8 group (P < 0.05) and there was no significant difference in A0, A4 and A16 groups. With the increase of dietary MOS, the activity of the total antioxidant capacity in hepatopancreas is increasingly elevated (P < 0.05) while no significant difference was observed on activity of glutathione S‐transferase (P > 0.05). The activities of superoxide dismutase and glutathione peroxidase were firstly increased and then decreased, with the highest values in A8 group (P < 0.05). Immune-related parameters were significantly affected by dietary MOS inclusion. Specifically, the activities of alkaline phosphatase and acid phosphatase in hepatopancreas and serum of abalone fed diets containing MOS were significantly higher than those of control A0 group (P < 0.05). Moreover, the highest values of both enzymes were observed in hepatopancreas of A8 group but in serum of A16 group, respectively. The lysozyme activities in hepatopancreas and serum of A4 group were significantly higher than those of other groups (P < 0.05) and there was no significant difference in A0, A8 and A16 groups (P > 0.05). The activities of cytophagy and respiratory burst in serum of abalone were not significantly affected by dietary MOS content (P > 0.05). The mRNA levels of focal adhesion kinase and integrin-linked kinase were gradually elevated with the increase of dietary MOS, with the highest value recorded in A16 group (P < 0.05). The gene expression of caspse-3 in A8 group was dramatically higher than those of other groups (P < 0.05) and there was no significant difference in A0, A4 and A16 groups (P > 0.05). The mRNA level of nuclear factor-κB was not significantly affected by dietary MOS (P > 0.05). During 56 h of V. Parahemolyticus challenge period, the accumulated mortality rate of abalone fed diets containing MOS were significantly lower than that of control A0 group in each time point (P < 0.05). Overall, the lowest rate was happened in A8 group (P < 0.05). In conclusion, MOS inclusion in diet has obviously positive effect on growth, immunity and disease resistance capability of abalone, with the optimal level of Actigen® at 0.80 g/kg in diet. • MOS had positive effect on growth, antioxidation and innate immunity in abalone. • MOS increased expressions of genes related to immune signal pathways. • MOS increased the disease resistance capability against Vibro in abalone. • The optimal addition level for MOS is 0.80 g/kg in diet in the form of Actigen®. [ABSTRACT FROM AUTHOR]

In previous study, it was found that the fractal dimension of the silica aerogel could be only controlled by adjusting the catalysts. In this work, we used the aging process investigated by Hæreid et al. to continuously adjust the fractal dimension of silica aerogel. The fractal structure of the silica aerogels were analyzed by small angle x-ray scattering (SAXS). The SAXS measurements show linear increases in the volume fractal dimension (2.32–2.64) of the secondary particles with aging time (0–72 h). This linear behavior is due to the silica precipitated from the aging solution to the secondary particles is at a constant rate. In the meantime, the light transmittances was obtained by ultraviolet–Visible–infrared spectrophotometer, extinction coefficient were obtained by fitting the curve of light transmittances. We developed a new model to build a connection between the extinction coefficient and the fractal dimension of the silica aerogel obtained by SAXS. From new model, it was found it is due to the increases in volume fractal dimension ( D f ) that result in increases of extinction coefficient and decreases of light transmittances. The optical transparency of silica aerogel is strongly affected by the volume fractal dimension ( D f ) of the secondary particles of silica aerogel. [ABSTRACT FROM AUTHOR]

Photosensitive ZrO 2 -SiO 2 hybrid sol-gel coatings containing large contents of chelating rings were prepared by using the zirconium n -butoxide (TBOZ) and methyltriethoxysilane (MTES) as hybrid precursors, and benzoylacetone (BZAC) as chelating agent. The change of ultraviolet (UV) absorption spectra, chemical composition, and optical properties of ZrO 2 -SiO 2 hybrid sol-gel coatings were analyzed before and after UV exposure and calcination. The refractive index of the ZrO 2 -SiO 2 hybrid gel coatings decreased from 1.673 to 1.561 with the increase of the molar content of MTES in precursors. The sol-gel coating patterns with the periods of 20.24 μm, 10.11 μm and 3.99 μm on the PAMS substrates were firstly obtained by using the photosensitive ZrO 2 -SiO 2 hybrid sol-gel films as fundamental materials through a process of UV contact lithography with photo masks and etching with ethanol. Finally, the free-standing gel coating patterns supported by copper grids, with the period of 12.70 μm and line width of 4.93 μm, and the period of 14.20 μm and line width of 3.82 μm, were obtained by removing the PAMS thermal degradation sacrifice layer after being calcined at 330 °C. Micrometer-periodic free-standing gel coating patterns with different structure have potential applications in the laser physical experiments. [ABSTRACT FROM AUTHOR]

A large number of electronic devices could generate a lot of electromagnetic waves, which could interfere with other equipment and harm the human body. Therefore, an electromagnetic interference shielding (EMI) material is urgently needed to protect the human body and the electronic equipment. In this paper, the multi-wall carbon nanotubes (MWCNTs) and the nano-Fe3O4 were added into the polylactic acid (PLA) matrix to form the composite film with electromagnetic interference shielding performance. And the structure and properties of MWCNTs/Fe3O4/PLA composite films, such as the morphology, chemical structure, crystallization, mechanical property, conductive property, magnetic property and electromagnetic interference shielding property, were researched. The result shows that too much Fe3O4 could lead to agglomeration, and the coupling agent KH570 had grafted and modified the surface of MWCNTs. The MWCNTs and nano-Fe3O4 could increase the crystallinity of PLA matrix. With the increase of MWCNTs, the maximum tensile stress of composite films gradually increased, and the maximum tensile strain decreased, and the resistance value showed a significant downward trend. The Fe3O4 could improve the magnetic properties of composite film. The MWCNTs and Fe3O4 could improve the electromagnetic interference shielding efficiency (EMI SE). The MWCNTs played a more significant role than the Fe3O4 in the process of EMI, and the EMI SE of the composite film with 3:1 ratios of MWCNTs/Fe3O4 could rise to 22 dB. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) surgical suture can be absorbed by human body. In order to avoid surgical site infections (SSIs), the drug is usually loaded on the PLA suture, and then the drug can release directly to the wound. Because the different types of wounds heal at different times, it is needed to control the drug release rate of PLA suture to consistent to the wound healing time. Two biopolymers, polyglycolide (PGA) and polycaprolactone (PCL), were selected as the carrier of ciprofloxacin (CPFX) drug, and then the CPFX-PCL/PGA was coated on the PLA suture. The degradation rate of drug-carrier can be controlled by adjusting the proportion of PCL/PGA, which can regulate the rate of CPFX drug release from PLA suture. The results show that the surface of PLA suture, coating with PCL/PGA, was very rough, which led to increased stitching resistance when we were suturing the wound. These materials, such as the PLA suture, the PCL/PGA carriers and the CPFX drug, were just physically mixed rather than chemically reacted, which was very useful for ensuring the original efficacy of CPFX drug. With the increasing of PCL in the carriers, both the breaking strength and elongation of these un-degraded sutures increased. During degradation, the breaking strength of all sutures gradually decreased, and the more PCL in the coating materials, the longer effective strength-time for the suture. With the increasing of PCL in the drug-carrier, the rate of drug releasing became lower. The drug release mechanism of CPFX-PCL/PGA was a synergistic effect of drug diffusion and PCL/PGA carrier dissolution. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) suture can be absorbed by the human body, and so have wide applications in modern surgery operations. The degradation period of PLA suture is expected to meet with the healing time of different types of wounds. In order to control the degradation period of the PLA suture, the carbon nanotubes (CNTs) were composited with PLA suture, and the degradation experiment in vitro was performed on sutures. The structure and properties of sutures during degradation, such as surface morphology, breaking strength, elongation, mass and chemical structure, were tracked and analyzed. The results indicated that the degradation brought about surface defects and resulted in 13.5 weeks for the strength valid time of the original PLA suture. By contrast, the strength valid time of the CNTs/PLA suture was increased to 26.6 weeks. Whilst the toughness of both the pure PLA and CNTs/PLA sutures decreased rapidly and almost disappeared after 3 to 4 weeks of degradation. The mass loss demonstrated that the time required for complete degradation of the two sutures was obviously different, the pure PLA suture 49 weeks, while CNTs/PLA sutures 63 to 73 weeks. The research proved that CNTs delayed PLA degradation and prolonged its strength valid time in degradation. [ABSTRACT FROM AUTHOR]