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Polyimide (PI) is widely deployed in space missions due to its good radiation resistance and durability. The influences from radiation and harsh temperatures should be carefully evaluated during the long-term service life. In the current work, the coupled thermal and radiation effects on the mechanical properties of PI samples were quantitatively investigated via experiments. At first, various PI specimens were prepared, and electron irradiation tests were conducted with different fluences. Then, both uniaxial tensile tests at room temperature and the dynamic mechanical analysis at varied temperatures of PI specimens with and without electron irradiation were performed. After that, uniaxial tensile tests at low and high temperatures were performed. The fracture surface of the PI film was observed using a scanning electron microscope, and its surface topography was measured using atomic force microscopy. In the meantime, the Fourier-transform infrared spectrum tests were conducted to check for chemical changes. In conclusion, the tensile tests showed that electron irradiation has a negligible effect during the linear stretching period but significantly impacts the hardening stage and elongation at break. Moreover, electron irradiation slightly influences the thermal properties of PI according to the differential scanning calorimetry results. However, both high and low temperatures dramatically affect the elastic modulus and elongation at break of PI. [ABSTRACT FROM AUTHOR]

Drug development for Alzheimer's disease, the leading cause of dementia, has been a long-standing challenge. Saponins, which are steroid or triterpenoid glycosides with various pharmacological activities, have displayed therapeutic potential in treating Alzheimer's disease. In a comprehensive review of the literature from May 2007 to May 2023, we identified 63 references involving 40 different types of saponins that have been studied for their effects on Alzheimer's disease. These studies suggest that saponins have the potential to ameliorate Alzheimer's disease by reducing amyloid beta peptide deposition, inhibiting tau phosphorylation, modulating oxidative stress, reducing inflammation, and antiapoptosis. Most intriguingly, ginsenoside Rg1 and pseudoginsenoside-F11 possess these important pharmacological properties and show the best promise for the treatment of Alzheimer's disease. This review provides a summary and classification of common saponins that have been studied for their therapeutic potential in Alzheimer's disease, showcasing their underlying mechanisms. This highlights the promising potential of saponins for the treatment of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Accurately estimating human pose is crucial for providing feedback during exercises or musical performances, but the complex and flexible nature of human joints makes it challenging. Additionally, traditional methods often neglect pixel coordinates, which are naturally present in high-resolution images of the human body. To address this issue, we propose a novel human pose estimation method that directly incorporates pixel coordinates. Our method adds a coordinate channel to the convolution process and embeds pixel coordinates into the feature map, while also using coordinate attention to capture position- and structure-sensitive features. We further reduce the network parameters and computational cost by using small-scale convolution kernels and a smooth activation function in residual blocks. We evaluate our model on the MPII Human Pose and COCO Keypoint Detection datasets and demonstrate improved accuracy, highlighting the importance of directly incorporating coordinate location information in position-sensitive tasks. [ABSTRACT FROM AUTHOR]

Simple Summary: The accurate prediction of growth traits in genomic selection (GS) is essential for pig breeding. Here, we performed GS using variants identified with three genome-wide association study methods on four growth-related traits in Yorkshire and Landrace pigs. A total of 1485 loci related to these traits and 24 candidate genes were mapped. Compared with using 60K SNP-chip data, GS with the pre-selected variants significantly improved prediction accuracies by 4 to 46% in genomic best linear unbiased prediction (GBLUP) models, and 5 to 27% in a two-kernel based GBLUP model for the four traits. Improving the prediction accuracies of economically important traits in genomic selection (GS) is a main objective for researchers and breeders in the livestock industry. This study aims at utilizing potentially functional SNPs and QTLs identified with various genome-wide association study (GWAS) models in GS of pig growth traits. We used three well-established GWAS methods, including the mixed linear model, Bayesian model and meta-analysis, as well as 60K SNP-chip and whole genome sequence (WGS) data from 1734 Yorkshire and 1123 Landrace pigs to detect SNPs related to four growth traits: average daily gain, backfat thickness, body weight and birth weight. A total of 1485 significant loci and 24 candidate genes which are involved in skeletal muscle development, fatty deposition, lipid metabolism and insulin resistance were identified. Compared with using all SNP-chip data, GS with the pre-selected functional SNPs in the standard genomic best linear unbiased prediction (GBLUP), and a two-kernel based GBLUP model yielded average gains in accuracy by 4 to 46% (from 0.19 ± 0.07 to 0.56 ± 0.07) and 5 to 27% (from 0.16 ± 0.06 to 0.57 ± 0.05) for the four traits, respectively, suggesting that the prioritization of preselected functional markers in GS models had the potential to improve prediction accuracies for certain traits in livestock breeding. [ABSTRACT FROM AUTHOR]

Highlights: What are the main findings? The intergranular Cu-rich phase formed by elemental segregation is not conducive to joint performance. The addition of Ti and Zr in the filler wire effectively refines the grain of the weld and also leads to coarse phases of Ti and Zr in the weld. Natural aging precipitation occurs in welds, and Al3Li particles or GPZs appear in the weld. What is the implication of the main finding? The main findings could provide guidance for Al-Li alloy filler wire design and weld aging rein-forcement. 2A55 Al-Li alloy is considered to have potential applications in the manufacture of fuel tanks for aerospace vehicles. However, the composition design of filler wires for 2A55 Al-Li alloy TIG welding has not been fully studied. This work focuses on the mechanical properties and microstructure of 2A55 Al-Li alloy TIG welded joints obtained using 2A55 alloy and Al-8Cu filler wire that was designed for this work, as well as the effects brought about by natural aging on them. When filler wire with higher Zr and Ti content was used, the weld grain was significantly refined. Due to the difference in the Cu content of filler wire, the formed Cu-rich phases in welds are significantly different, showing a grid-like distribution in the Al-8Cu weld compared to the dispersed distribution in the 2A55 weld. After welding, the lack of dominant strengthening precipitates caused a sharp softening of the welds. However, Li and Cu atoms dissolved in the Al matrix can precipitate fine and dispersed Al3Li particles and GPZs by natural aging to strengthen the welds. After natural aging, the yield strength (YS) of the 2A55 joint increased by 24.1% compared with the 14.7% improvement of the Al-8Cu joint. [ABSTRACT FROM AUTHOR]

Aluminum (Al)–copper (Cu)–lithium (Li) alloys are susceptible to environmental degradation, which limits the in-service lifetime of the components. Because of their complex composition, there are seldom studies focusing on corrosion behavior influenced by one single element, which is essential to clarify the corrosion mechanism. Herein, the sole influence of Mg on the corrosion behavior of Al–Cu–Li–xMg alloys was analyzed. Results revealed that the addition of Mg can affect the nucleation and precipitation process of the T1 precipitate, resulting in a difference of potential between grain interior and grain boundary. The precipitation of the T1 precipitate was promoted in a 0.7Mg alloy while impeded in a 1.1Mg alloy, due to the competition of Cu atoms and nucleation sites between T1 and S′. Two types of corrosion behavior of Al–Cu–Li–xMg alloys appeared due to the potential difference and continuity of grain boundaries. Continuous precipitates in grain boundaries and less precipitates within the grain are likely to cause intergranular corrosion (IGC), while more precipitates within the grain will result in pitting. [ABSTRACT FROM AUTHOR]

An accurate and efficient automatic brain tumor segmentation algorithm is important for clinical practice. In recent years, there has been much interest in automatic segmentation algorithms that use convolutional neural networks. In this paper, we propose a novel hierarchical multi-scale segmentation network (HMNet), which contains a high-resolution branch and parallel multi-resolution branches. The high-resolution branch can keep track of the brain tumor's spatial details, and the multi-resolution feature exchange and fusion allow the network's receptive fields to adapt to brain tumors of different shapes and sizes. In particular, to overcome the large computational overhead caused by expensive 3D convolution, we propose a lightweight conditional channel weighting block to reduce GPU memory and improve the efficiency of HMNet. We also propose a lightweight multi-resolution feature fusion (LMRF) module to further reduce model complexity and reduce the redundancy of the feature maps. We run tests on the BraTS 2020 dataset to determine how well the proposed network would work. The dice similarity coefficients of HMNet for ET, WT, and TC are 0.781, 0.901, and 0.823, respectively. Many comparative experiments on the BraTS 2020 dataset and other two datasets show that our proposed HMNet has achieved satisfactory performance compared with the SOTA approaches. [ABSTRACT FROM AUTHOR]

In this paper, the change in the mechanical properties of a composite plate was studied using the heat treatment method, and it was found that the performance of the composite plate was greatly improved under the process of quenching at 900 °C and tempering at 200 °C. The hot-rolled NM500/Q345 clad plates were subjected to heat treatment tests of 860 °C, 900 °C, and 940 °C austenitization + 200 tempering. With the help of an optical microscope, scanning electron microscope, EBSD, and transmission electron microscope, the microstructure, interface element distribution, and defect composition at the composite bonding interface of hot rolling and heat treatment were analyzed. An analysis and friction and wear tests were carried out on the wear resistance of the clad NM500. It was found that the microstructure of the NM500/Q345 clad plate before austenitization was mainly pearlite and ferrite, and both were transformed into lath martensite after austenitization. As the austenitization temperature increased, the size of the martensitic lath bundle also became coarse. After austenitization at 900 °C and tempering at 200 °C, the lath-like martensite structure of NM500 contained high-density dislocations between the laths. With the increase in the austenitization temperature, the surface Rockwell hardness showed a trend of first increasing and then decreasing. The wear was the worst when the material was not quenched. When the clad plate was quenched at 900 °C and tempered at 200 °C, the wear of NM500 was the lightest; the maximum depth of the wear scar was 14 μm; the width was the narrowest, 0.73 mm; and the wear volume was the smallest, 0.0305 mm3. [ABSTRACT FROM AUTHOR]

The space-charge field (SCF) is a key factor in vacuum electronic devices, accelerators, free electron lasers and plasma systems, etc. The calculation of the SCF is very important since it has a great influence on the precision of numerical simulation results. However, calculating the SCF usually takes a lot of time, especially when the number of simulated particles is large. In this paper, we used a vectorization, parallelization and truncation method to optimize the calculation of the SCF based on the traditional calculation algorithms. To verify the validity of the optimized SCF calculation algorithm, it was applied in the performance simulation of a millimeter wave traveling wave tube. The results showed that the time cost was reduced by three orders compared with conventional treatment. The proposed algorithm also has great potential applications in free electron lasers, accelerators and plasma systems. [ABSTRACT FROM AUTHOR]

Iron-manganese co-oxide film (MeOx) has a high removal efficiency for ammonium (NH4+) and manganese (Mn2+) in our previous studies, but it cannot effectively remove CODMn from water. In this study, the catalytic oxidation ability of MeOx was enhanced by dosage with potassium ferrate (K2FeO4) to achieve the simultaneous removal of CODMn and NH4+ from water in a pilot-scale experimental system. By adding 1.0 mg/L K2FeO4 to enhance the activity of MeOx, the removal efficiencies of CODMn (20.0 mg/L) and NH4+ (1.1 mg/L) were 92.5 ± 1.5% and 60.9 ± 1.4%, respectively, and the pollutants were consistently and efficiently removed for more than 90 days. The effects of the filtration rate, temperature and pH on the removal of CODMn were also explored, and excessive filtration rate (over 11 m/h), lower temperature (below 9.2 °C) and pH (below 6.20) caused a significant decrease in the removal efficiency of CODMn. The removal of CODMn was analyzed at different temperatures, which proved that the kinetics of CODMn oxidation was pseudo-first order. The mature sands (MeOx) from column IV were taken at different times for microscopic characterization. Scanning electron microscope (SEM) showed that some substances were formed on the surface of MeOx and the ratio of C and O elements increased significantly, and the ratio of Mn and Fe elements decreased significantly on the surface of MeOx by electron energy dispersive spectrometer (EDS). However, the elemental composition of MeOx would gradually recover to the initial state after the dosage of Mn2+. According to X-ray photoelectron spectroscopy (XPS) analysis, the substance attached to the surface of MeOx was [(-(CH2)4O-)n], which fell off the surface of MeOx after adding Mn2+. Finally, the mechanism of K2FeO4-enhanced MeOx for CODMn removal was proposed by the analysis of the oxidation process. [ABSTRACT FROM AUTHOR]

Common buckwheat (Fagopyrum esculentum M.) is an important pseudo-cereal crop and contains an abundance of nutrients and bioactive compounds. However, the yield of buckwheat is low compared to that of other major crops. QTL mapping and candidate gene screening of grain size are very important for increasing production in common buckwheat through molecular breeding in the future. In the present study, an F1 segregating population with 217 individuals was established using a cross between Ukraine daliqiao (UD) and Youqiao 2 (YQ2) that showed a significant difference in grain size. The InDel and SSR primers were developed based on transcriptome sequencing between parents in the previous study. We constructed a genetic linkage map, including 39 SSR loci and 93 InDel loci, with a total length of 1398.33 cM and an average spacing of 10.59 cM. Combined with the grain size phenotype data of the F1 population, a total of 14 QTL were detected, including 6-grain length QTL, 3-grain width QTL, and 5 hundred-grain-weight QTL. QTL of grain width and hundred-grain weight were all detected near SWU_Fe_InDel086 and SWU_Fe_InDel076. Some putative candidate genes with the ex1pression or InDel difference between parents were screened within the QTL interval. This study would lay the foundation for map-based cloning and molecular mechanism of grain size and ultimately improvement of yield in common buckwheat. [ABSTRACT FROM AUTHOR]

As a nano-carbon material with excellent properties, Graphene oxide (GO) has been widely used in cement-based materials, and the negative effect of paste workability caused by GO agglomeration has also been widely concerning. In this study, a polycarboxylate-silane modified graphene oxide composite (PSG) was prepared by coupling polycarboxylate molecules to the surface of graphene oxide (GO) via a reaction with vinyl triethoxysilane. The effects of GO and PSG on the cement paste and the mechanisms underpinning these effects were investigated using fluidity and rheological parameter measurements, and ion concentration and zeta potential analyses. It was found that, in the aqueous phase of the paste, the polycarboxylate molecular chains on the surface of the PSG complexed with calcium ions (Ca2+), thereby preventing Ca2+ from bridging the GO sheets, and thus stabilizing the surface potential and the electrostatic repulsion. This prevented the PSG from forming an agglomerate structure such as that formed by GO under the same conditions, thereby substantially enhancing workability of paste with nano-carbon material. This study provides some new foundations and ideas for the further application of graphene oxide materials in cement-based materials. [ABSTRACT FROM AUTHOR]

Plankton microorganisms play central roles in the marine food web and global biogeochemical cycles, while their distribution and abundance are affected by environmental variables. The determinants of microbial community composition and diversity in estuaries and surrounding waters with multiple environmental gradients at a fine scale remain largely unclear. Here, we investigated bacterial and protistan community assembly in surface waters from 27 stations across the Changjiang Estuary to the ocean, with salinity ranging from 0 to 32.1, using 16S rRNA and 18S rRNA gene amplicon sequencing. Statistical analyses revealed that salinity is the major factor structuring both bacterial and protistan communities. Salinity also acted as a significant environmental determinant influencing alpha-diversity patterns. Alpha diversity indices for bacterial and protistan communities revealed a species minimum in higher-salinity waters (22.1–32.1). Contrary to the protistan community, the highest bacterial diversity was identified in medium-salinity waters (2.8–18.8), contrasting Remane's Artenminimum concept. The distribution of major planktonic taxa followed the expected pattern, and the salinity boundary for Syndiniales was specifically identified. These findings revealed the significant effects of salinity on the microbial community across an estuary to ocean transect and the distinct response to salinity between bacterial and protistan communities. [ABSTRACT FROM AUTHOR]

State of charge (SOC) estimation is the core of any battery management system. Most closed-loop SOC estimation algorithms are based on the equivalent circuit model with fixed parameters. However, the parameters of the equivalent circuit model will change as temperature or SOC changes, resulting in reduced SOC estimation accuracy. In this paper, two SOC estimation algorithms with online parameter identification are proposed to solve this problem based on forgetting factor recursive least squares (FFRLS) and nonlinear Kalman filter. The parameters of a Thevenin model are constantly updated by FFRLS. The nonlinear Kalman filter is used to perform the recursive operation to estimate SOC. Experiments in variable temperature environments verify the effectiveness of the proposed algorithms. A combination of four driving cycles is loaded on lithium-ion batteries to test the adaptability of the approaches to different working conditions. Under certain conditions, the average error of the SOC estimation dropped from 5.6% to 1.1% after adding the online parameters identification, showing that the estimation accuracy of proposed algorithms is greatly improved. Besides, simulated measurement noise is added to the test data to prove the robustness of the algorithms. [ABSTRACT FROM AUTHOR]

Owing to their good stability and high photothermal conversion efficiency, the development of carbon-based nanoparticles has been intensively investigated, while the limitation of unsatisfactory cellular internalization impedes their further clinical application. Herein, we report a novel strategy for fabrication of Fe3O4 yolk–shell mesoporous carbon nanocarriers (Fe3O4@hmC) with monodispersity and uniform size, which presented significantly higher cell membrane adsorption and cellular uptake properties in comparison with common solid silica-supported mesoporous carbon nanoparticles with core–shell structure. Moreover, the MRI performance of this novel Fe-based nanoparticle could facilitate precise tumor diagnosis. More importantly, after DOX loading (Fe3O4@hmC-DOX), owing to synergistic effect of chemo–phototherapy, this therapeutic agent exhibited predominant tumor cell ablation capability under 808 nm NIR laser irradiation, both in vitro and in vivo. Our work has laid a solid foundation for therapeutics with hollowed carbon shell for solid tumor diagnosis and therapy in clinical trials. [ABSTRACT FROM AUTHOR]

The long-path differential optical absorption spectroscopy (LP-DOAS) technique was deployed in Shanghai to continuously monitor ozone (O3), formaldehyde (HCHO), nitrogen dioxide (NO2), nitrous acid (HONO), and nitrate radical (NO3) mixing ratios from September 2019 to August 2020. Through a clustering method, four typical clusters of the O3 diurnal pattern were identified: high during both the daytime and nighttime (cluster 1), high during the nighttime but low during the daytime (cluster 2), low during both the daytime and nighttime (cluster 3), and low during the nighttime but high during the daytime (cluster 4). The drivers of O3 variation for the four clusters were investigated for the day- and nighttime. Ambient NO caused the O3 gap after midnight between clusters 1 and 2 and clusters 3 and 4. During the daytime, vigorous O3 generation (clusters 1 and 4) was found to accompany higher temperature, lower humidity, lower wind speed, and higher radiation. Moreover, O3 concentration correlated with HCHO for all clusters except for the low O3 cluster 3, while O3 correlated with HCHO/NOx, but anti-correlated with NOx for all clusters. The lower boundary layer height before midnight hindered O3 diffusion and accordingly determined the final O3 accumulation over the daily cycle for clusters 1 and 4. The interactions between the O3 diel profile and other atmospheric reactive components established that higher HONO before sunrise significantly promoted daytime O3 generation, while higher daytime O3 led to a higher nighttime NO3 level. This paper summarizes the interplays between day- and nighttime oxidants and oxidation products, particularly the cause and effect for daytime O3 generation from the perspective of nighttime atmospheric components. [ABSTRACT FROM AUTHOR]

The unique thermal history of selective laser melting (SLM) can lead to high residual stress and a non-equilibrium state in as-fabricated titanium alloy components and hinders their extensive use. Post heat treatment, as a classical and effective way, could transform non-equilibrium α' martensite and achieves desirable mechanical performance in SLMed Ti alloys. In this study, we aimed to establish the correlation between the microstructure and mechanical performances of SLMed Ti6Al4V (Ti-64) by using different heat treatment processes. The columnar prior β grain morphology and grain boundary α phase (GB-α) after different heat treatment processes were characterized, with their influences on the tensile property anisotropy fully investigated. Scanning electron microscope (SEM) observation of the fracture surface and its cross-sectional analysis found that the tensile properties, especially the ductility, were affected by the GB-α along the β grain boundary. Furthermore, the discontinuous ratio of GB-α was firstly proposed to quantitatively predict the anisotropic ductility in SLMed Ti-64. This study provides a step forward for achieving the mechanical property manipulation of SLMed Ti-64 parts. [ABSTRACT FROM AUTHOR]

The applications of terahertz (THz) devices in communication, imaging, and plasma diagnostic are limited by the lack of high-power, miniature, and low-cost THz sources. To develop high-power THz source, the high-harmonic traveling wave tube (HHTWT) is introduced, which is based on the theory that electron beam modulated by electromagnetic (EM) waves can generate high harmonic signals. The principal analysis and simulation results prove that amplifying high harmonic signal is a promising method to realize high-power THz source. For further improvement of power and bandwidth, two novel dual-beam schemes for high-power 346 GHz TWTs are proposed. The first TWT is comprised of two cascaded slow wave structures (SWSs), among which one SWS can generate a THz signal by importing a millimeter-wave signal and the other one can amplify THz signal of interest. The simulation results show that the output power exceeds 400 mW from 340 GHz to 348 GHz when the input power is 200 mW from 85 GHz to 87 GHz. The peak power of 1100 mW is predicted at 346 GHz. The second TWT is implemented by connecting a pre-amplification section to the input port of the HHTWT. The power of 600 mW is achieved from 338 GHz to 350 GHz. The 3-dB bandwidth is 16.5 GHz. In brief, two novel schemes have advantages in peak power and bandwidth, respectively. These two dual-beam integrated schemes, constituted respectively by two TWTs, also feature rugged structure, reliable performance, and low costs, and can be considered as promising high-power THz sources. [ABSTRACT FROM AUTHOR]

In this paper, CNTs@PANi nanocomposites were prepared by in-situ oxidation polymerization of aniline, and their structure, morphology and conductivity were characterized. A mixed solvent of toluene and tetrahydrofuran was used to prepare dispersions of CNTs@PANi and poly(styrene-ethylene-butylene-styrene) (SEBS) triblock copolymer, and bilayer composite film was prepared. According to the solvent phase separation and uneven evaporation flux, CNTs@PANi self-assembled into the interconnected coffee ring structure on the SEBS matrix. The prepared bilayer composite film had excellent stretchability, and the conductivity of the functional layer was close to that of CNTs@PANi, which could light up an LED lamp under 100% strain and restore the topological structure. Electrochemical tests showed that the bilayer film had obvious heterogeneity. The impedance characteristics of the CNTs@PANi functional layer and the SEBS matrix were analyzed, and its heterogeneous corrosion resistance mechanism further discussed. [ABSTRACT FROM AUTHOR]

The model parameters of the lithium-ion battery are of great importance to model-based battery state estimation methods. The fact that parameters change in different rates with operation temperature, state of charge (SOC), state of health (SOH) and other factors calls for an online parameter identification algorithm that can track different dynamic characters of the parameters. In this paper, a novel multiple forgetting factor recursive least square (MFFRLS) algorithm was proposed. Forgetting factors were assigned to each parameter, allowing the algorithm to capture the different dynamics of the parameters. Particle swarm optimization (PSO) was utilized to determine the optimal forgetting factors. A state of the art SOC estimator, known as the unscented Kalman filter (UKF), was combined with the online parameter identification to create an accurate estimation of SOC. The effectiveness of the proposed method was verified through a driving cycle under constant temperature and three different driving cycles under varied temperature. The single forgetting factor recursive least square (SFFRLS)-UKF and UKF with fixed parameter were also tested for comparison. The proposed MFFRLS-UKF method obtained an accurate estimation of SOC especially when the battery was running in an environment of changing temperature. [ABSTRACT FROM AUTHOR]

Open circuit voltage (OCV) is an important characteristic parameter of lithium-ion batteries, which is used to analyze the changes of electronic energy in electrode materials, and to estimate battery state of charge (SOC) and manage the battery pack. Therefore, accurate OCV modeling is a great significance for lithium-ion battery management. In this paper, the characteristics of high-capacity lithium-ion batteries at different temperatures were considered, and the OCV-SOC characteristic curves at different temperatures were studied by modeling, exponential, polynomial, sum of sin functions, and Gaussian model fitting method with pulse test data. The parameters of fitting OCV-SOC curves by exponential model (n = 2), polynomial model (n = 3~7), sum of sin functions model (n = 3), and Gaussian model (n = 4) at temperatures of 45 °C, 25 °C, 0 °C, and −20°C are obtained, and the errors are analyzed. The experimental results show that the operating temperature of the battery influences the OCV-SOC characteristic significantly. Therefore, these factors need to be considered in order to increase the accuracy of the model and improve the accuracy of battery state estimation. [ABSTRACT FROM AUTHOR]

The use of high-capacity batteries as the battery pack of electric vehicles is the current development trend. In order to better design battery packages and battery management systems and develop related battery estimation technology, the related characteristics of high capacity battery cells need to be studied in depth. Capacity and pulse tests of batteries at different temperatures are carried out in this paper. Through these experimental data, the electrical characteristics of different parameters of the high capacity battery, such as capacity characteristic data, internal resistance characteristic data, OCV-SOC characteristic relation curve, power data and temperature rise are analyzed. The specific parameters of the battery in the second order equivalent circuit model are obtained by using the off-line parameter identification method. These parameters results can be used as comparison data and reference data. It is beneficial to the on-line parameter identification of battery model and the estimation of battery state, so as to shorten the development time and improve the quality of the development. [ABSTRACT FROM AUTHOR]

Sate of charge (SOC) accurate estimation is one of the most important functions in a battery management system for battery packs used in electrical vehicles. This paper focuses on battery SOC estimation and its issues and challenges by exploring different existing estimation methodologies. The key technologies of lithium-ion battery state estimation methodologies of the electrical vehicles categorized under five groups, such as the conventional method, adaptive filter algorithm, learning algorithm, nonlinear observer, and the hybrid method, are explored in an in-depth analysis. Lithium-ion battery characteristic, battery model, estimation algorithm, and cell unbalancing are the most important factors that affect the accuracy and robustness of SOC estimation. Finally, this paper concludes with the challenges of SOC estimation and suggests other directions for possible research efforts. [ABSTRACT FROM AUTHOR]

State of charge (SOC) estimation is becoming increasingly important, along with electric vehicle (EV) rapid development, while SOC is one of the most significant parameters for the battery management system, indicating remaining energy and ensuring the safety and reliability of EV. In this paper, a hybrid wavelet neural network (WNN) model combining the discrete wavelet transform (DWT) method and adaptive WNN is proposed to estimate the SOC of lithium-ion batteries. The WNN model is trained by Levenberg-Marquardt (L-M) algorithm, whose inputs are processed by discrete wavelet decomposition and reconstitution. Compared with back-propagation neural network (BPNN), L-M based BPNN (LMBPNN), L-M based WNN (LMWNN), DWT with L-M based BPNN (DWTLMBPNN) and extend Kalman filter (EKF), the proposed intelligent SOC estimation method is validated and proved to be effective. Under the New European Driving Cycle (NEDC), the mean absolute error and maximum error can be reduced to 0.59% and 3.13%, respectively. The characteristics of high accuracy and strong robustness of the proposed method are verified by comparison study and robustness evaluation results (e.g., measurement noise test and untrained driving cycle test). [ABSTRACT FROM AUTHOR]

An iron-manganese co-oxide filter film (MeO x ) has been proven to be a good catalyst for the chemical catalytic oxidation of ammonium in groundwater. Compared with groundwater, surface water is generally used more widely and has characteristics that make ammonium removal more difficult. In this study, MeO x was used to remove ammonium from surface water. It indicated that the average ammonium removal efficiency of MeO x was greater than 90%, even though the water quality changed dramatically and the water temperature was reduced to about 6-8 °C. Then, through inactivating microorganisms, it showed that the removal capability of MeO x included both biological (accounted for about 41.05%) and chemical catalytic oxidation and chemical catalytic oxidation (accounted for about 58.95%). The investigation of the characterizations suggested that MeO x was formed by abiotic ways and the main elements on the surface of MeO x were distributed homogenously. The analysis of the catalytic oxidation process indicated that ammonia nitrogen may interact with MeO x as both ammonia molecules and ammonium ions and the active species of O₂ were possibly • O and O₂ - .