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Polysaccharides are a kind of biological macromolecule, which widely exists in plants, fungi, animals, microorganisms, and other organisms. Polysaccharides exhibit various biological activities such as immunological regulation, antioxidation, antitumor, antiinflammatory, regulating intestinal flora, and protecting liver. These biological activities depend on their structure and physicochemical properties including monosaccharide composition, molecular weight (Mw), spatial configuration, etc. However, biological activities of polysaccharides are hardly comparable to synthetic drugs due to their inherent physicochemical properties. Therefore, structural modification of polysaccharides is an effective way to enhance their biological activities and promote the presentation of bioactivity. At present, phosphorylation modification is a common chemical modification method, which can effectively improve the biological activities of polysaccharides. However, there are limited reports on the synthesis, structure identification, and biological activities of phosphorylated polysaccharides. In view of this, the synthesis methods, structure identification methods, and biological activities of phosphorylated polysaccharides are reviewed in this paper. The findings can provide useful guidance for the research, production, and application of phosphorylated polysaccharides in functional foods and therapeutic agents. [ABSTRACT FROM AUTHOR]

The two models of microwave assisted aqueous two‐phase extraction (MATPE) of polysaccharides from Malus hupehensis are established by response surface methodology (RSM) and back propagation neural network (BP‐NN), compared their prediction ability, and comparatively optimized extraction process by using RSM and BP‐NN coupled genetic algorithm (GA), and the antioxidant activity of M. hupehensis polysaccharides (MHPs) is evaluated by the scavenging ability of free radicals. The results show that the predictive ability of BP‐NN is significantly better than that of RSM. The optimal extraction parameters to achieve the highest MHPs yield (4.71 ± 0.04)% by MATPE are obtained through BP‐NN coupled GA method under the microwave power of 337 W, mass fraction of ammonium sulfate of 23%, ethanol concentration of 29%, and liquid‐to‐solid ratio of 22 mL g−1. The IC50 values of 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and hydroxyl radicals (OH) scavenging capacities for MHPs achieve 5.13 and 3.29 mg mL−1, respectively. The findings provide important references for the development and utilization of M. hupehensis. [ABSTRACT FROM AUTHOR]

AbstractFruits and vegetables contain polysaccharides, polyphenols, antioxidant enzymes, and various vitamins, etc. Fruits and vegetables polysaccharides (FVPs), as an important functional factor in health food, have various biological activities such as lowering blood sugar, blood lipids, blood pressure, inhibiting tumors, and delaying aging, etc. In addition, FVPs exhibit good physicochemical properties including low toxicity, biodegradability, biocompatibility. Increasing research has confirmed that FVPs could enhance the stability and biological activities of anthocyanins, affecting their bioavailability to improve food quality. Simultaneously, the addition of FVPs in natural starch suspension could improve the physicochemical properties of natural starch such as viscosity, gelling property, water binding capacity, and lotion stability. Hence, FVPs are widely used in the modification of natural anthocyanins/starch. A systematic review of the latest research progress and future development prospects of FVPs is very necessary to better understand them. This paper systematically reviews the latest progress in the extraction, purification, structure, and analysis techniques of FVPs. Moreover, the review also introduces the potential mechanisms, evaluation methods, and applications of the interaction between polysaccharides and anthocyanins/starch. The findings can provide important references for the further in-depth development and utilization of FVPs. [ABSTRACT FROM AUTHOR]

This study aimed to explore the interaction and antiaging characteristics of composite phase change materials in asphalt for long-term temperature adjustment of asphalt pavement. First, the epoxy resin/phase change materials (E-PCMs) modified asphalt binders were prepared by the melt blending method, and their microscopic, rheological, and temperature adjustment properties were tested. Finally, the long-term performance of the modified asphalt binders was evaluated by simulated aging. The results show that E-PCMs are well dispersed in the modified asphalt binders. E-PCMs can improve the temperature sensitivity and high-temperature stability of asphalt binders, and they could reduce the fluidity of asphalt molecules at high-temperature. The extreme temperature of the E-PCMs–modified asphalt binders can be reduced by 10.4°C and have an excellent temperature adjustment effect. The aged modified asphalt binders still have excellent temperature adjustment properties, and the survival rate of phase change enthalpy is 88%. E-PCMs could also prevent the oxidative aging of asphalt molecules and reduce the adverse effects of the photothermal environment on asphalt. It provides reference and basis for the large-scale promotion and application of temperature-adjusting pavement, which reduces the temperature disease of asphalt pavement and the near-surface thermal environment. [ABSTRACT FROM AUTHOR]

In this study, water and air were used as simulated media to investigate the spray characteristics of a gas-centered swirl coaxial (GCSC) injector under different ambient pressures through experimental, simulation, and theoretical approaches. The results showed that for the same liquid mass flow rate, the breakup length of the liquid film decreased with increasing ambient pressure, with the extent of the decrease diminishing as the ambient pressure increased. In addition, it was found that under the same ambient pressure, the larger the liquid mass flow rate, the shorter the liquid film breakup length. Moreover, for any gas–liquid mass flow ratio (GLR), the spray angle increased significantly with ambient pressure, and the liquid film suddenly expanded compared to the no-ambient pressure condition. At the same time, the breakup length of the liquid film increased. As ambient pressure increased, the spray angle increased while the breakup length decreased. When the GLR was small, self-pulsation occurred, which gradually disappeared with increasing ambient pressure. The frequency of self-pulsation decreased with increasing ambient pressure. The periodic self-pulsation of the spray was the result of the combined effects of the centrifugal force of the rotating liquid film, surface tension of the liquid film, aerodynamic force, and pressure difference inside and outside the liquid film. Overall, these findings provide insight into the spray characteristics of GCSC injectors under different ambient pressures, which can be of importance to the design and optimization of liquid rocket engines. [ABSTRACT FROM AUTHOR]

Based on steady-state experiments, a three-dimensional (3D) simulation study under pulsation conditions was carried out. This was performed to study the effect of pulsation of the supply system on the atomization characteristics of a gas-centered swirl coaxial injector. The results indicated that the spray shape resembled a pagoda when the Klystron effect occurred. When the low-frequency pulsation (200 Hz) was applied to the liquid inlet, the peak of the exit pressure was close to the trough of the inlet mass flow rate. Meanwhile, the exit mass flow rate and pressure were approximately sinusoidal. There was no significant lag effect in the response of the exit mass flow rate to the inlet mass flow rate but with a small sawtooth-like oscillation. Increasing the amplitude of the liquid inlet disturbance amplified the exit mass flow rate fluctuation, which was greater than the set amplitude of the inlet pulsation. The dominant frequency of the injector exit mass flow rate and pressure variation was significantly less than the inlet pulsation frequency when the frequency of the liquid inlet pulsation was increased to 1000 Hz. This was due to the low-pass filtering effect of the annular slit. There was no significant change in the overall spray morphology for the gas inlet pulsation. By applying the same amplitude and frequency of pulsation to the gas and liquid inlets of the injector, the pulsation of the liquid inlet had a stronger effect on the injector exit spray than that of the gas inlet. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the changes in adhesion performance between recycled asphalt pavement (RAP) materials and aggregates by the regeneration process. The oil-rich RAP fine aggregate was utilized to assess the adhesion performance and its improvement between recycled asphalt mortar and aggregates. Various testing methods, such as contact angle test, dynamic shear rheometer (DSR), atomic force microscopy (AFM), and water stability tests, were employed to comprehensively analyze and evaluate the adhesion performance of oil-rich RAP fine aggregate in the regeneration process of recycled asphalt mortar at multi-scale. The results show that alkaline aggregate limestone and SBS-modified asphalt exhibit higher adhesion work by surface-free energy theory. The anti-stripping agents XTA2 and LQ20 can improve the adhesion area between recycled asphalt and aggregates. Under the same influencing factors, SBS-modified asphalt, aggregate, and additive type can all improve adhesion performance between recycled asphalt mortar and aggregates. The recycled asphalt mixture prepared from SBS-modified asphalt has a freeze-thaw splitting tensile strength ratio (TSR) increase of 3.5∼10 % compared to matrix asphalt, limestone can increase TSR by 2∼6 % compared to basalt, and TSR increases by 7∼10 % before and after adding anti stripping agents. The mechanism of adhesion performance enhancement in recycled asphalt mortar was analyzed from a micro/nano perspective. That provides a reference for the durability development of RAP recycled asphalt pavement. • The adhesion of aged asphalt in oil-rich RAP fine aggregate increased by 14.7 %. • The water stability performance of mixture is improved by 10 % through the increase of oil-rich RAP fine aggregate adhesion. • The study revealed the adhesion enhancement mechanism of oil-rich RAP fine aggregate recycled asphalt. [ABSTRACT FROM AUTHOR]

High-quality asphalt with a composite modifier is necessary for the high-grade pavement to meet the requirements. In this study, nano-organic palygorskite (O-PAL) was successfully prepared by acid activation and silane modification. O-PAL, together with styrene-butadiene-styrene block copolymer (SBS) modified asphalt, was prepared by melt blending. O-PAL composite SBS modified asphalt can form a multi-phase homogeneous system with a spinodal strengthened structure, which can improve the properties of asphalt. 3 wt% O-PAL composite SBS modified asphalt showed excellent water stability; and the critical temperature of the modified asphalt increased up to 40% by adding O-PAL. O-PAL can not only reduce the aging of the asphalt matrix but also reduce the thermal decomposition oxidation of linear SBS. The anti-aging and storage stability performance of the composite modified asphalt is also improved by the addition of O-Pal. O-PAL and SBS are quite a good combination for modified asphalt in high-temperature and humid areas. Unlabelled Image • Organic palygorskite(O-PAL) and its modified asphalt were prepared. • The spinodal strengthened structure of O-PAL and SBS was formed. • The combination property of asphalt could be improved by the incorporation of O-PAL and SBS. [ABSTRACT FROM AUTHOR]

Iron is an essential trace element in the human body. Iron deficiency can lead to iron deficiency anemia (IDA) and induce various diseases. Hence, it is urgent to find an iron supplement with minimal side effects and good iron supplementation effect. Natural polysaccharides from plants have various biological activities such as antioxidant, hypoglycemic, immunomodulatory, etc. Increasing research has shown that polysaccharides modified with iron can enhance their biological activities. Among them, polysaccharide iron complex (PIC) has significant anti‐anemia activity. With the powerfully development of PIC, increasing research has found that PIC showed some advantages, including good water solubility, high bioavailability, low gastrointestinal irritation, and high iron content. Therefore, PIC has received widespread attention. Currently, PIC is widely used in various fields such as agriculture, animal husbandry, and clinical treatment. However, there are limited reports on the preparation, biological activities, and applications of PIC. This paper systematically reviews the preparation methods, iron content determination methods, biological activities, and applications of PIC. The results provide important references for the deep development and utilization of PIC. [ABSTRACT FROM AUTHOR]

• SiO 2 -PCMs has been successfully prepared and features excellent compatibility, thermal performance and anti-leakage ability. • PEG/SiO 2 shows excellent ability to adjust the pavement temperature. • The heat transfer model provide reference and theoretical support for temperature adjustment. In recent years, extreme temperatures have occurred frequently in summer, which is a challenge to asphalt pavement and its surrounding environment. Phase change materials (PCMs) have unique energy storage characteristics, which provide a new idea for alleviating the high-temperature damage of pavement and reducing the environment temperature. In this paper, the silica composite phase change materials (SiO 2 -PCMs) were prepared by the sol–gel method, and SiO 2 -PCMs with better performance was applied to the asphalt mixture. The finite element heat transfer model was established by measuring the boundary conditions, and the temperature adjustment effect was predicted and analyzed. SiO 2 -PCMs meet the mixing temperature requirements of asphalt mixtures and have excellent compatibility, thermal cycle stability and anti-leakage ability. Asphalt mixture with PEG/SiO 2 has an excellent temperature adjustment effect, and it can reduce the upper surface temperature of the asphalt mixture by about 9 °C. The high unity of theory and experiment is implemented by establishing the heat transfer model. PCMs reduce the temperature of asphalt pavement by storing and transforming energy, which provides reference and theoretical support for improving the near-surface thermal environment and prolonging the service life of asphalt pavement. [ABSTRACT FROM AUTHOR]

In engineering applications, many real-world optimization problems are nonlinear with multiple local optimums. Traditional algorithms that require gradients are not suitable for these problems. Meta-heuristic algorithms are popularly employed to deal with these problems because they can promisingly jump out of local optima and do not need any gradient information. The arithmetic optimization algorithm (AOA), a recently developed meta-heuristic algorithm, uses arithmetic operators (multiplication, division, subtraction, and addition) to solve optimization problems including nonlinear ones. However, the exploration and exploitation of AOA are not effective to handle some complex optimization problems. In this paper, an opposition learning and spiral modelling based AOA, namely OSAOA, is proposed for enhancing the optimization performance. It improves AOA from two perspectives. In the first perspective, the opposition-based learning (OBL) is committed to taking both candidate solutions and their opposite solutions into consideration for improving the global search with a high probability of jumping out of local minima. Then, the spiral modelling is introduced as the second perspective, which is particularly useful in getting the solutions gathering faster and accelerating the convergence speed in the later stage. In addition, OSAOA is compared with other existing advanced meta-heuristic algorithms based on 23 benchmark functions and four engineering problems: the three-bar truss design, the cantilever beam design, the pressure vessel design, and the tubular column design. From our simulations and engineering applications, the proposed OSAOA can provide better optimization results in dealing with these real-world optimization problems. [ABSTRACT FROM AUTHOR]

Edible fungus is widely eaten because of their delicious taste and high nutritional value. Growing evidence indicates that edible fungus is rich in various active ingredients including polysaccharides, proteins, fats, vitamins, and other ingredients. Polysaccharides are one of the main active ingredients of edible fungi. Increasing research has confirmed that edible fungus polysaccharides (EFPs) show multiple biological activities such as antioxidant, anti‐inflammatory, anti‐tumor, immune regulation, anti‐virus, gut microbiota regulation, hypoglycemic, etc. Hence, EFP related research has received more and more attention due to their non‐toxic, high medical, and nutritional values. This paper reviews the latest research progress of EFPs biological activities, and looks forward to their future development trend. This review provides a theoretical basis for studying the application of EFPs in the fields of biomedicine, cosmetics, health food, and promotes the development and utilization of EFPs. [ABSTRACT FROM AUTHOR]

Polysaccharides are another important class of bioactive macromolecules in organisms, in addition to proteins and nucleic acids. Numerous studies have confirmed that polysaccharides have various biological activities, including anti‐inflammatory, antiviral, antioxidant, immunomodulatory, anticancer, and other activities, which have attracted the attention of researchers in the biomedical field. In the past decade, increasing researches have found that sulfation modification can improve many physicochemical properties of polysaccharides, significantly enhance their original biological activities, and even generate new activity. Hence, sulfated polysaccharides have attracted more and more attention. A systematic review of the latest research progress and future development prospects of sulfated polysaccharides is very essential to better understand them. Hence, the study has systematically summarized current knowledge about synthesis, structural characteristics, biological activities, and potential molecular mechanisms of sulfated polysaccharides. This review provides some valuable insights and important guidance for the further study of sulfated polysaccharides. [ABSTRACT FROM AUTHOR]

With the rapid development of economic construction, styrene-butadiene-styrene (SBS)-modified asphalt is being more and more widely used in highway engineering, but there are still many deficiencies in the process of its use. In order to further improve its performance for use, nano-organic palygorskite (A-Pal) and star-shaped SBS were compounded to obtain modified asphalt in this study. The high-temperature stability of SBS-modified asphalt was enhanced after incorporation with A-Pal for the high-temperature stability test by a dynamic shear rheometer. The A-Pal should improve the surface free energy and adhesion of SBS-modified asphalt by the water stability test analysis. The aging test shows that A-Pal can reduce the thermal oxygen decomposition of SBS and improve the anti-aging performance and the fatigue resistance of SBS-modified asphalt. A-Pal has a certain improvement effect on the low temperature performance of SBS-modified asphalt as shown by a low temperature crack resistance test. A-Pal-compounded SBS-modified asphalt features good storage stability in normal temperatures with the lowest critical compatibility temperature. [ABSTRACT FROM AUTHOR]

• Organic palygorskite (A-Pal) was prepared by the grafting reaction. • The optimal content of A-Pal modified asphalt is 4% ~ 6%. • The spatial network structure of A-Pal was formed in the matrix asphalt for better rheological and aging properties. This paper aims to promote the application of nano-mineral materials in asphalt and improve the compatibility of modifiers with asphalt to produce high-performance and economical modified asphalt. In this paper, palygorskite (Pal) was organic grafted by γ-aminopropyltriethoxysilane (ATPES) to obtain an organomodified palygorskite (A-Pal). Then A-Pal was adopted to modify asphalt by melt blending with different contents. The microstructure and elemental distribution of the modified asphalt were characterized to confirm the interface state of different components. The rheology, water stability and aging resistance of Pal and A-Pal in the asphalt were evaluated. The organic group was successfully grafted on the surface of Pal, and A-Pal had good compatibility with asphalt. Adding A-Pal could enhance the water stability, high-temperature stability and anti-rutting capacity of asphalt binder. The thermo-oxidative aging resistance of asphalt increased after TFOT and PAV aging under the shielding effect of A-Pal fibers. Considering high- and low-temperature performances, water stability, anti-aging performances and economic benefits, the optimal amount of A-Pal in asphalt was recommended from 4 to 6%. A-Pal has been proved to be an excellent and environmental-friendly asphalt modifier for the nanofiber effect. [ABSTRACT FROM AUTHOR]

The adverse impact of vehicle emissions on the roadside environment is becoming increasingly serious. Traditional catalytic materials exhibit a singular practical effect and are prone to aggregation within asphalt systems. This study employed organic montmorillonite (MMT) as a two-dimensional nanomaterial load-bearing phase for graphitic carbon nitride (g-C3N4) based on the structural features of available materials and the concept of composite material construction, resulting in the synthesis of a g-C3N4/MMT composite material (CN-M). The phase composition, binding behavior, thermal stability, physical adsorption capacity, and morphology of CN-M were studied systematically. The results demonstrate that CN-M possesses stable properties and structural morphology. The specific surface area of CN-M is 3.38 times that of g-C3N4 , indicating superior spatial confinement capabilities. A comprehensive analysis was conducted from both macroscopic and microscopic perspectives on the modification mechanism, rheological characteristics, aging behavior, and catalytic performance of the modified asphalt. It is speculated that CN-M disperses in a layered state within the asphalt binder, effectively restricting the movement of asphalt macromolecular chains. When the CN-M content reached 5%, the modified asphalt exhibited a high-temperature critical temperature of 71.6°C, showcasing optimal high-temperature rheological performance and aging resistance. The prepared modified asphalt mixture demonstrated the ability for waste degradation, achieving a degradation rate of 21.66% for nitric oxide (NO). The research results provide technical support for the development and application of catalytic asphalt materials. [ABSTRACT FROM AUTHOR]

In extreme learning machine (ELM) framework, the hidden layer setting determines its generalization ability; and in presence of outliers in the training set, weights between hidden layer and output layer based on the least squares would be overly estimated. To address these two problems in ELM implementation, we extend robust penalized statistical framework in ELM and propose a general robust penalized ELM, which consists of two components (robust loss function and regularization item), for regression to improve the efficiency of ELM training with more elegant neural network structure resulting in more accurate predictions. We investigate six different loss functions ( l 1 -norm loss, l 2 -norm loss, Huber loss, Bisquare loss, exponential squared loss and Lncosh loss) and two regularization strategies (lasso penalty and ridge penalty). Furthermore, we present two training procedures for our robust penalized ELM via iterative reweighted least squares method with hyper-parameter setting by cross-validation with lasso penalty and ridge penalty, respectively. Finally, the proposed robust penalized ELM is employed in an ultra-short-term wind speed forecasting study, and our framework is confirmed in this specific application producing more effective predictions according to the multi-step forecasting performance. [ABSTRACT FROM AUTHOR]

The incidence of diabetes, as a metabolic disease characterized by high blood sugar levels, is increasing every year. The predominantly western medicine treatment is associated with certain side effects, which has prompted people to turn their attention to natural active substances. Natural polysaccharide is a safe and low-toxic natural substance with various biological activities. Hypoglycemic activity is one of the important biological activities of natural polysaccharides, which has great potential for development. A systematic review of the latest research progress and possible molecular mechanisms of hypoglycemic activity of natural polysaccharides is of great significance for better understanding them. In this review, we systematically reviewed the relationship between the hypoglycemic activity of polysaccharides and their structure in terms of molecular weight, monosaccharide composition, and glycosidic bonds, and summarized underlying molecular mechanisms the hypoglycemic activity of natural polysaccharides. In addition, the potential mechanisms of natural polysaccharides improving the complications of diabetes were analyzed and discussed. This paper provides some valuable insights and important guidance for further research on the hypoglycemic mechanisms of natural polysaccharides. [ABSTRACT FROM AUTHOR]

Hawthorn (Crataegus pinnatifida Bge.) contains various active components including polysaccharides, polyphenols, vitamin, phenolic acid, etc. Polysaccharides are one of the most critical active components in hawthorn, which exhibits different biological activities such as immunomodulatory antioxidant, anti‐inflammatory, hypoglycemic, and other activities. Hence, the main purpose of this paper is to optimize the aqueous two‐phase extraction (UTPE) of polysaccharides from hawthorn via a response surface methodology coupled genetic algorithm (RSM‐GA) and then evaluate its antioxidant activity through free radicals scavenging experiments. The results show that the optimal extraction conditions to achieve the maximum polysaccharides yield (6.42 ± 0.08)% from hawthorn by UTPE is obtained under the mass fraction of ammonium sulfate of 11%, extraction temperature of 57 °C, liquid‐to‐solid ratio of 33 mL g−1, ethanol concentration of 26%, and extraction time of 30 min, and the relative error between the experimental value and the theoretical value is 4.56%. The antioxidant capacity is enhanced with the increase of hawthorn polysaccharides (HPs) concentration. However, the antioxidant activity of HPs is weaker than that of ascorbic acid. The results of this study provide a critical material basis for promoting the further research of HPs, and have certain significance for the deep processing and product development of hawthorn. [ABSTRACT FROM AUTHOR]

This study conducted 3D numerical simulations to investigate the impact of combustion chamber diameter on the combustion characteristics of liquid kerosene scramjet rotating detonation under high Mach number flow conditions (Ma6/28 km). After ignition, a local hotspot near the contact surface between the combustion product and fresh reactant facilitates the generation of new detonation wave heads, resulting in a co-directional multi-wave mode in the detonation combustion flow field. The higher total temperature of the incoming flow restricts the accumulation of a substantial fuel gas layer in the axial direction of the combustion chamber, resulting in a smaller fuel distribution area and a lower wave head. Increasing the inner diameter of the combustion chamber leads to an increase in the number of wave heads but a decrease in overall height. Specifically, when using diameters of 125 and 150 mm, we observed significant periodic low-frequency oscillations in the peak pressure of the detonation wave during stable propagation. The specific impulse of the fuel does not vary significantly across different combustion chamber diameters. However, when the inner diameter is 75 mm, periodic oscillations occur, which reduce thrust stability. These findings provide valuable insights into optimizing combustion chamber design and improving the efficiency and stability of liquid kerosene scramjet rotating detonation propulsion systems under high Mach number flow conditions. [ABSTRACT FROM AUTHOR]

110 kinds of traditional Chinese medicines can be used for medicine and food from Chinese pharmacopoeia in 2021. With the deepening of research in recent years, medicinal and edible homologous (MEH) traditional Chinese medicines have great development and application prospects in many fields. Polysaccharides are one of the major and representative pharmacologically active macromolecules in traditional Chinese medicines with MEH. Moreover, traditional Chinese medicines with MEH have become the main source of natural polysaccharides with safety, high efficiency, and low side effects. Increasing researches have confirmed that MEH polysaccharides (MEHPs) have multiple biological activities both in vitro and in vivo methods, such as antioxidant, immunomodulatory, anti-tumor, anti-aging, anti-inflammatory, hypoglycemic, hypolipidemic activities, and regulating intestinal flora. Additionally, different raw materials, extraction, purification, and chemical modification methods result in differences in the structure and biological activities of MEHPs. The purpose of the present review is to provide comprehensively and systematically reorganized information in the extraction, purification, structure, modification, biological activities, and potential mechanism of MEHPs to support their therapeutic effects and health functions. New valuable insights and theoretical basis for the future researches and developments regarding MEHPs were proposed in the fields of medicine and food. • Extraction and purification methods of MEHPs were summarized. • Structure and chemical modification of MEHPs were reviewed. • The characteristics of various extraction and purification methods were outlined. • Diverse biological activities and potential mechanisms of MEHPs were outlined. [ABSTRACT FROM AUTHOR]

As unsupervised learning algorithm, clustering algorithm is widely used in data processing field. Density-based spatial clustering of applications with noise algorithm (DBSCAN), as a common unsupervised learning algorithm, can achieve clusters via finding high-density areas separated by low-density areas based on cluster density. Different from other clustering methods, DBSCAN can work well for any shape clusters in the spatial database and can effectively cluster exceptional data. However, in the employment of DBSCAN, the parameters, EPS and MinPts, need to be preset for different clustering object, which greatly influences the performance of the DBSCAN. To achieve automatic optimization of parameters and improve the performance of DBSCAN, we proposed an improved DBSCAN optimized by arithmetic optimization algorithm (AOA) with opposition-based learning (OBL) named OBLAOA-DBSCAN. In details, the reverse search capability of OBL is added to AOA for obtaining proper parameters for DBSCAN, to achieve adaptive parameter optimization. In addition, our proposed OBLAOA optimizer is compared with standard AOA and several latest meta heuristic algorithms based on 8 benchmark functions from CEC2021, which validates the exploration improvement of OBL. To validate the clustering performance of the OBLAOA-DBSCAN, 5 classical clustering methods with 10 real datasets are chosen as the compare models according to the computational cost and accuracy. Based on the experimental results, we can obtain two conclusions: (1) the proposed OBLAOA-DBSCAN can provide highly accurately clusters more efficiently; and (2) the OBLAOA can significantly improve the exploration ability, which can provide better optimal parameters. [ABSTRACT FROM AUTHOR]

Accurate power load forecasting has a significant effect on a smart grid by ensuring effective supply and dispatching of power. However, electric load data generally possesses the characteristics of nonlinearity, periodicity, and seasonality. For complex electric load systems, the presence of redundant information potentially reduces the real pattern extraction for load forecasting. Bearing in mind these issues, we propose an effective forecasting model in which a feature extraction module is introduced that is combined with the variational mode decomposition (VMD) with the variational autoencoder (VAE). In this combination, VMD is utilized for decomposing complex load series and VAE is used to filter the redundant information (noises) from each decomposed series. With two real data sets from China, we demonstrate that the proposed model can achieve highly accurate predictions, as we find the mean absolute percentage error (MAPE) values for one-step-ahead prediction to be 1% (Nanjing) and 0.8% (Taixing), respectively. • A dimensionality reduction approach is proposed. • A novel combination method is designed for load forecasting. • The proposed approach can improve the accuracy in actual projects. [ABSTRACT FROM AUTHOR]

Traditional Chinese medicines are tremendous sources of polysaccharides, which are of great interest in the human welfare system as natural medicines, food, and cosmetics. This review aims to highlight the recent trends in extraction (conventional and non-conventional), purification and analytic techniques of traditional Chinese medicine polysaccharides (TCMPs), and the chemical structure, biological activities (anti-tumor, hypoglycemic, antioxidant, intestinal flora regulation, immunomodulatory, anti-inflammatory, anti-aging, hypolipidemic, hepatoprotective, and other activities), and the underlying mechanisms of polysaccharides extracted from 76 diverse traditional Chinese medicines were compared and discussed. With this wide coverage, a total of 164 scientific articles were searched from the database including Google Scholar, PubMed, Web of Science, and China Knowledge Network. This comprehensive survey from previous reports indicates that TCMPs are non-toxic, highly biocompatible, and good biodegradability. Besides, this review highlights that TCMPs may be excellent functional factors and effective therapeutic drugs. Finally, the current problems and future research advances of TCMPs are also introduced. New valuable insights for the future researches regarding TCMPs are also proposed in the fields of therapeutic agents and functional foods. [ABSTRACT FROM AUTHOR]

• SA/DI featured preferable thermal reliability and chemical stability. • The maximum peak temperature reduction of upper and bottom surface can reach at 10.9 °C and 5.03 °C, respectively. • The heat transfer model and the thermal conductivity properties were consistent with the actual test results. It is an important research field to restrict the extreme temperature of pavement by using the robust thermal performance of phase change materials. In this study, diatomite, expanded perlite, and stearic acid were chosen to prepare compound phase change materials (CPCMs) for the fabrication of novel cooling asphalt pavement. The microtopography and characteristics of CPCMs were described by scanning electronic micro-scopy, Fourier transform infrared spectroscopy and X-ray diffraction. The thermal performance and stability were confirmed by thermogravimetric analysis and differential scanning calorimetry. The cooling asphalt pavement was evaluated by pavement performance and thermal performance test. Finally, the heat transfer simulation of the cooling asphalt pavement and the conventional asphalt pavement were established by the finite element method. CPCMs with diatomite as carrier still feature superior chemical and thermal stability after 100 cycles. The upper and bottom surface temperatures of the asphalt pavement can be reduced by 10.90 °C and 5.03 °C, respectively. The temperature gradient at each stage showed that the addition of CPCMs helps to restrict the extreme temperature of the pavement, and has the potential to restrict the temperature extremities in pavement and the effect of urban heat island. [ABSTRACT FROM AUTHOR]

To address issues related to the limited improvement in the performance of phase-change material (PCMs) modified asphalt and the unclear underlying mechanisms, this study developed two structurally stable and thermally efficient coal gangue composite phase-change agents. The impact on enhancing the properties of asphalt was systematically investigated. The study revealed that when the dosage of the phase-change agent is below 20%, there was a pronounced interactive effect between the agent and asphalt. This interaction had the capability to regulate both the non-polar and polar components within the asphalt colloid system. By controlling the dosage of the PCMs agent, it was possible to enhance the high-temperature rheological properties, high-temperature shear resistance and low-temperature flexibility of the asphalt. Additionally, this control improved the adhesion and moisture sensitivity of the PCMs modified asphalt and aggregate system. The maximum temperature-regulating effect of PCMs modified asphalt could reach up to 8.3 °C, with the functional attribute strongly correlated with the low-temperature performance of the asphalt. This research contributes to the promotion and application of PCMs in road engineering. • The service performance of asphalt can be improved by adding CPER or APER. • The adhesion between phase change asphalt and mineral aggregates was enhanced. • CPER or APER can endow asphalt with the temperature regulation ability. [ABSTRACT FROM AUTHOR]

Nd 2 Fe 14 C-based magnet is prepared by a mechanochemical method, namely high-energy ball-milling Nd 2 Fe 11 B x (x = 0–0.15) alloy in heptane (C 7 H 16 ), followed by annealing to 850 °C in vacuum. Under the action of high-energy ball-milling, Nd 2 Fe 11 B x react with heptane to form NdH 2+δ , Fe-(CB), C, etc. H 2 is released and Nd 2 Fe 17 , Nd 2 Fe 17 C x (x = 0–3), Nd 2 Fe 14 C, Nd carbides and α-Fe are formed in the subsequent annealing. C amount depends on ball-milling time t . Long time ball milling or high C content suppresses the formation of 2:17 phase and favors the formation of 2:14:1 phase in the final products. Excessive ball-milling results in the quick increase of α-Fe. The maximum of magnetically hard Nd 2 Fe 14 C is obtained at t = 4 h. For Nd 2 Fe 11 samples, there exists considerable quantity of Nd carbides and α-Fe phase appears earlier and increases rapidly with extending the ball-milling time t . The addition of B element shortens the ball-milling time of the formation of maximum Nd 2 Fe 14 C and prominently suppresses the formation of Nd carbide and α-Fe. The optimum magnetic properties, coercivity i H c of 1193.7 kA/m, remanence M r of 580.9 kA/m, maximum magnetic energy product ( BH ) max of 91.7 kJ/m 3 is approaching to its theoretic value of 99.2 kJ/m 3 for isotropic Nd 2 Fe 14 C magnet, are obtained in Nd 2 Fe 11 B 0.06 alloy ball milled for 3.5 h. [ABSTRACT FROM AUTHOR]

• The feasibility of coal gangue with different structural characteristics in road engineering was demonstrated. • Coal gangue by microstructure adjustment can promote stable structures in asphalt for durable pavement. • Sustainable development of coal gangue in asphalt pavement materials. The efficient application of coal gangue into asphalt pavement materials not only improves pavement service performance, but also relieves environmental pressure of accumulation. However, the compatibility of coal gangue powder with asphalt pavement materials promises further strengthens, calling for enhanced processing schemes of coal gangue. Firstly, modified materials were successfully prepared by modulating the coal gangue powder. A series of microscopic experiments were conducted to characterize the phase structure, microstructure, thermal stability, adsorption capacity, and functional group change characteristics of different types of coal gangue powder. Then, three kinds of coal gangue powders were applied to the matrix asphalt by melt blending method, and the composite's rheological properties and aging resistance were also studied. Finally, the modification mechanism of the composite was discussed from the micro level. The research showed that the specific surface area of intercalated and activated coal gangue powder increased about 1.45 times and 1.25 times, respectively, compared with ordinary coal gangue powder. The physical adsorption capacity of gangue powder can be improved by chemical intercalation or high-temperature activation. The high-temperature resistance and anti-aging performance of asphalt can be affected by enhancing the interaction between coal gangue powder and the asphalt matrix. The design of coal gangue modified asphalt materials with different structural characteristics promotes the development of sustainable and durable pavement. [ABSTRACT FROM AUTHOR]

In this paper, we present a new preparation method for Sm 2 Fe 17 C x compound based on solid-liquid reaction. High-energy ball-milled in heptane for 8 h, Sm 25 Fe 75 alloy containing SmFe 2 , SmFe 3 and Sm 2 Fe 17 phases disproportionates into SmH 2 + δ , α-Fe, Fe 3 C and graphite. H and C atoms come from heptane. Annealed to 850 °C under vacuum, SmH 2 + δ decomposes and Sm-C, Sm 2 Fe 14 C, α-Fe are formed. Re-milling for 1.5 h in argon and re-annealing at 600 °C for 15 min promotes the transformation of partial Sm 2 Fe 14 C to Sm 2 Fe 17 C x ( x : 0.3–1.5) and the formation of nanoscale microstructure. Due to the intergrain exchange coupling between magnetically hard Sm 2 Fe 17 C x and soft Sm 2 Fe 14 C/α-Fe, the product behaves like magnet with single magnetically hard phase. Maximum coercivity of 4.4 kOe is obtained. Shorter ball-milling time (6 h) results in the insufficiency of α-Fe and Fe 3 C, limiting the formation of Sm 2 Fe 14 C and the transformation of Sm 2 Fe 14 C to Sm 2 Fe 17 C x . Longer ball-milling time (10 h) results in excess of α-Fe in the final product. Both cases reduce the ratio of magnetically hard phase to soft one in the nanocomposite magnet, resulting in the decrease of coercivity. [ABSTRACT FROM AUTHOR]

• Hard spots (caused by speckle segregation) and surface defects (caused by porosity) lead to stress concentrations that form crack sources. • Axial cracks, pores and inclusions can accelerate the propagation of cracks. • Axial inclusions are rated and analyzed. The steering knuckle of a truck with a load capacity of 22 tons broke during driving, and the wheel fell off; the truck had travelled only 1100 km. The composition, mechanical properties, fracture morphology, and microstructure of the failed parts were investigated. The results showed that the heat treatment of the steering knuckle is standardised. The composition of the raw material meets the relevant standard; however, spot segregation, pores, axial cracks, and inclusions appear in the raw material. Cracks originate from hard spots, which are caused by spot segregation, and surface defects, which are caused by pores. Axial cracks, pores, and inclusions can accelerate crack growth and cause rapid fracture of parts. According to the inspection and analysis results, we propose a product quality inspection and control scheme to the manufacturer. [ABSTRACT FROM AUTHOR]