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Large stone porous asphalt mixes (LSPMs) have the characteristics of large gaps, large content of coarse aggregate, and large particle size of coarse aggregate. Compared with the traditional asphalt-treated base (ATB), LSPM forms a more obvious skeleton structure in the process of bearing load. In this study, the discrete element method (DEM) model of LSPM is established, and an evaluation method for studying the bearing capacity and high-temperature performance of LSPM through an internal skeleton network is proposed. Firstly, the DEM model of asphalt mixture with different gradations is established, and the virtual uniaxial penetration test is carried out. Then, the performance of the skeleton network inside the asphalt mixture is analyzed, and the contribution of each group of aggregates to the skeleton network is further studied. The experimental results show that the bearing capacity of an asphalt mixture is closely related to the performance of internal skeleton network. The skeleton network inside the asphalt mixture is extracted by the value of the contact force, the angle between the contacts, and the contact continuity. When the skeleton network has better bearing capacity and load-transfer capacity, the asphalt mixture can bear more external load in the virtual penetration test. The contribution of different coarse aggregates to the skeleton network is analyzed from four perspectives: total contact force, vertical work, contact number, and effective coordination number. The aggregates of 19–26.5 and 4.75–9.5 mm constitute the main body of the load-transfer path and play a major role in bearing and transmitting the load in the skeleton network. [ABSTRACT FROM AUTHOR]

The heating temperature field of asphalt pavement is a key factor affecting the quality of pavement heat-in-place recycling (HIR). Using the heat transfer characteristics of HIR, a three-dimensional heat transfer model was simplified into a one-dimensional heat transfer model along the depth direction. A temperature sensor was installed on the site to monitor the temperature change of the asphalt pavement at different depths under different heating powers, and the actual temperature and heat transfer model were highly compatible. Through this model, the influence of heater running speed and heater heat flux density on the temperature field of the asphalt pavement heated by infrared radiation (IR) was calculated by the finite differential method, and an optimal combination of heating is proposed. In accordance with construction continuity and minimum energy consumption principles, at the 3.0–3.5 m/min recommended running speed of the heating machine, the asphalt at a depth of 4 cm satisfied the temperature demand, but the asphalt on the road surface was prone to heat aging. The heating effect of the constant temperature variable power heating (CTVP) is ideal, but the continuous change in heating power increases the difficulty of construction. Constant temperature discrete power heating (CTDP) divides the ideal heat flux density curve into several stages according to the length of the heating plate in the heater, increasing the feasibility of constant temperature heating in engineering and reducing energy consumption. The mileage of roads in some countries has basically satisfied the needs of national development, and the research focus of road workers has gradually shifted from building new roads to the renovation and maintenance of existing roads. In order to meet the purposes of convenient transportation and environmental protection at the same time, construction optimization must be carried out in the process of road renovation and maintenance to ensure that energy is not wasted during the construction process, and the relevant requirements of construction specifications are met. At present, high proportion of paved roads throughout the world have asphalt pavement. HIR has gradually become a popular maintenance method in order to save resources. In this method, the heating temperature field of the original asphalt pavement plays a key role in the construction quality, and the temperature field is affected by many factors, such as the running speed of the heater and the heat flux density of the heater during the heating process. This study mainly considers the foregoing two factors, combined with the actual situation of the project, in order to find a heating method with excellent heating effects and simple construction. The heating effect of the pavement is further optimized, improving the quality of the project, while saving energy and reducing the project cost. [ABSTRACT FROM AUTHOR]

In this work, the low-power-loss Mn–Zn ferrite was prepared by the traditional ceramic sintering process. This sample shows the good wide-temperature stability of power loss (P cv). In the whole measurement temperature range of 25 - 120 °C, P cv s maintain less than 100, 682, and 1455 kW/m3 at 100 kHz/100 mT, 500 kHz/100 mT and 800 kHz/100 mT, respectively. The effect of uniaxial compressive stress on power loss at 100, 500 and 800 kHz was investigated. Stress has greater impact on P cv at high frequencies and P cv increases remarkably. To clarify the mechanism of stress on power loss, P cv was divided into three parts including hysteresis loss (P hv), eddy current loss (P ev) and residual loss (P rv), and the effect of stress on each part of loss was discussed. At the low frequency of 100 kHz, P cv is mainly contributed by P hv. The applied stress leads the local anisotropic stress and makes domain wall displacement more difficult, which is the reason of the increase of P hv. When frequency increases to 500 and 800 kHz, P ev and P rv become more important. The compressive stress is in favour of electron transfer between Fe3+ and Fe2+ in grains and electron tunnelling effect at grain boundaries, which leads to the decrease of resistivity. This is the origin of enhanced P ev under the compressive stress. The enhanced P rv is related to the enhanced electronic diffusion under the compressive stress. The clarification of the mechanism of stress on power loss is beneficial to develop new soft ferrite materials with low stress sensitivity for high-frequency applications. [ABSTRACT FROM AUTHOR]

To meet the challenge of varied working temperatures of inductance components in new energy vehicle and 5G communication, the high- T C high-permeability MnZn ferrite with excellent temperature stability was developed by the addition of SnO 2. In this series of samples, initial permeability μ i maintains large values in a wide temperature range. With increasing the SnO 2 content, the temperature of the second permeability peak T sp decreases and meanwhile Curie temperature T C maintains as high as 160 °C. For the best sample with 6000 ppm SnO 2 , μ i at 25 °C is 7244 and exhibits the excellent temperature stability with the low specific temperature coefficient of 0.35 × 10−6 °C−1 between 25 and 130 °C. The addition of SnO 2 generates Fe2+ and adjusts the magneto-crystalline anisotropy constant K 1 = 0 point, which is responsible for the wide-temperature high permeability. The effect of SnO 2 addition on magnetization process has also been clarified. [ABSTRACT FROM AUTHOR]

Ulcerative colitis (UC) is relevant to dysregulation of inflammation and immune processes. Sophora flavescens Aiton is a classic medicine widely used in the treatment of UC in ancient and modern China, alkaloids and flavonoids are the main components. Previous studies reveal that Sophora flavescens Aiton total flavonoids extracts (SFE) exert an anti-UC effect by regulating the intestinal microbe structure and restoring the balance of the "host-microbe" co-metabolic network in UC mice. However, whether SFE influences immune inflammation remains unclear, which is the core link to UC disease. It also remains to be verified flavonoids are the material basis that plays a role in SFE. To identify the action mechanism of the immune-inflammatory regulation of SFE and its main active component Kurarinone against UC. This study constructed UC mice and abnormal immune RAW 264.7 cell models, and subsequently used western blotting and flow cytometry (FCM) to evaluate the effects of SFE on the NF-κB pathway and the regulation of immunity in UC mice. Kurarinone was screened from flavonoid compounds of SFE by lipopolysaccharide (LPS)-induced RAW 264.7 cells, and its effect was subsequently investigated in UC mice. Western blotting, ELISA, FCM, and RT-PCR were used to determine the regulation of Kurarinone on the Th17/Treg differentiation and the JAK2/STAT3 signaling pathway. SFE regulated the differentiation of Th17/Treg in peripheral blood and inhibited immune-inflammatory response to treat UC. Various flavonoid components in SFE inhibited the synthesis of IL-6 and TNF-α in RAW 264.7 cells, among which Kurarinone had better effect. This study revealed the therapeutic effects of Kurarinone in UC mice for the first time. Kurarinone promoted the secretion of SIgA to improve the regulation of the intestinal mucosal barrier and resistance to pathogens. It also regulated the transcription level of RORγt and Foxp3 in colon, decreased the expression of pro-inflammatory factor IL-17A and up-regulated the expression of immunosuppressive factors TGF-β1 and IL-10 in colon. Furthermore, Kurarinone restored intestinal immune system homeostasis by down-regulating the JAK2/STAT3 signaling pathway and regulating the balance of Th17/Treg cell differentiation in UC. SFE, especially the flavonoid ingredients represented by Kurarinone, has significant effects on immunoregulation against UC. And their mechanism of effect is related to inhibiting the activation of JAK2/STAT3 signaling pathway and regulating differentiation of Th17/Treg cells. Immunoregulatory; Kurarinone; Th17 cells; Treg cells; Ulcerative colitis. [Display omitted] • SFE inhibited the levels of inflammatory cytokines in UC mice. • SFE could regulate the homeostasis of Th17/Treg cells in peripheral blood. • Kurarinone had therapeutic effect in UC mice. • Kurarinone regulated the homeostasis of Th17/Treg differentiation. • Kurarinone inhibited the overactivation of JAK2/STAT3 signaling pathway. [ABSTRACT FROM AUTHOR]

The densified MnZn ferrite ceramics were prepared using the cold sintering process under pressure, with an acetate ethanol solution used as the transient solvent. The effects of the transient solvent, the pressure and annealing temperature on the density, and the micromorphology and magnetic properties of the sintered MnZn ferrites were studied. The densified MnZn ferrite was obtained using the cold sintering process and its relative density reached up to 85.4%. The transient solvent and high pressure are essential to the cold sintering process for MnZn ferrite. The annealing treatment is indispensable in obtaining the sample with the higher density. The relative density was further increased to 97.2% for the sample annealed at 950 °C for 6 h. The increase in the annealing temperature reduces the power loss at high frequencies. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to explore the relationships between the construction sector and the rest of the Chinese economy in the energy consumption as it is crucial in energy consumption of the whole economy. Therefore, this paper uses the Modified Hypothetical Extraction Method (MHEM) to quantify the linkages of energy consumption in 2002, 2005, 2007, 2010, 2012, 2015, 2017 and 2018, providing a new perspective for energy consumption linkage studies in China. In this paper we discover the volumes and paths of energy consumption net flows from other blocks to the construction sector and identify the key energy suppliers of the construction sector. The empirical findings show that the indirect energy consumption exceeded the direct energy consumption between 2002 and 2018, representing more than 90% of total (direct plus indirect) energy consumption of the construction sector. Between 2002 and 2018, the indirect energy consumption of the construction sector increased from 27,579 to 111,760 × 104 tons of coal equivalent (tce). We further find that the construction sector has the largest inflows of energy consumption to obtain its own demand than other sectors from 2002 to 2018. The average annual energy consumption net flows from other seven sectors to the construction sector were 1477, 687, 47,998, 6067, 1483, 7362 and 1923 × 104 tce in 2002–2018, respectively. Moreover, we find that the Manufacturing sector is the largest energy supplier of the construction sector between 2002 and 2018. [ABSTRACT FROM AUTHOR]

In this study, MnZn ferrites with added YIG nanoparticles were developed for MHz frequency applications. The effect of the magnetic YIG additive on the power loss, initial permeability, and cutoff frequency of MnZn ferrites was investigated. A small quantity of added YIG effectively reduces the power loss and concurrently increases the initial permeability. Compared to the results for the MnZn ferrite with no added YIG, the optimal MnZn ferrite with 600 ppm added YIG exhibits a reduction in the power loss at 25°C of 56.4% and 36.6% at 1 MHz/50 mT and 3 MHz/10 mT, respectively, and a 13.9% increase in the initial permeability. This sample also exhibits a good stability of the power loss against temperature. The power loss remains below 205 kW/m3 over temperatures ranging from 25 to 140°C. The effect mechanism of YIG addition on the magnetic properties of MnZn ferrites was studied. An analysis based on the equivalent circuit model showed that the reduction in the eddy current loss and power loss mainly results from the increase in the grain boundary resistance caused by the addition of highly resistive YIG. [ABSTRACT FROM AUTHOR]

An ultrathin seal serves as a preventive maintenance technology. The design method predominantly relies on engineering experience and lacks a theoretical foundation. In order to investigate the impact of aggregate size, spreading mass, and original pavement texture depth on the formation of an ultrathin seal, a compaction model was developed using the discrete element method (DEM). Different aggregate sizes and spreading masses were analyzed to examine the particle structure and thickness. The three-dimensional (3D) Weierstrass–Mandelbrot (WM) function was used to reconstruct random rough surfaces to assess the effect of the original pavement texture depth (1, 2, 3, and 4 mm) on voids and dosage of filling asphalt. Results showed that the dynamic compaction led to a rapid increase in collision velocity and then declined sharply by 0.02 s, eventually reaching zero by 0.3 s. Particle contacts steadily increased to 365 by 0.3 s and kept stable after the plateau, indicating the formation of an interlocking structure. Coordination numbers and contact vectors varied with particle size and spreading mass, which were more pronounced for small particles. However, the smaller particles (<4.5 mm) had negligible compaction effects, suggesting that the optimal aggregate size should be 3–5 mm. Excessive spreading mass resulted in a multilayered structure incompatible with the single thickness requirement and the recommended range was 9–12 kg/m2. Furthermore, greater texture depth led to higher void content at the bottom of the seal, requiring more filling asphalt. Therefore, when designing asphalt dosage, both the compaction and the variation in voids due to the original pavement texture depth should be considered to ensure sufficient contacts. [ABSTRACT FROM AUTHOR]

This paper presents a virtual generation method for the heterogeneous microstructure of asphalt mixtures. The coarse aggregates used in the digital asphalt mixture were derived from real aggregates captured by a three-dimensional (3D) laser scanner. Then, a rigid-body dynamic simulation framework was proposed to generate a stable skeletal structure composed of coarse aggregates similar to those formed by compaction. Furthermore, FAM and air voids were generated based on the generated aggregate skeleton and the assumption of equal thickness of FAM film. To prove the reliability of the model, the air voids of the digital asphalt mixture samples were verified by comparison with real specimens. The generated digital specimens were also applied to finite element method (FEM) simulations to predict the dynamic modulus of the asphalt mixture and the simulated results were in good agreement with the experimental results. The method can be applied to study the spatial distribution of asphalt mixture components, the movement pattern of aggregate particles during compaction and numerical simulations at the microscopic scale. [ABSTRACT FROM AUTHOR]

This paper presents a virtual generation method for the heterogeneous microstructure of asphalt mixtures. The coarse aggregates used in the digital asphalt mixture were derived from real aggregates captured by a three-dimensional (3D) laser scanner. Then, a rigid-body dynamic simulation framework was proposed to generate a stable skeletal structure composed of coarse aggregates similar to those formed by compaction. Furthermore, FAM and air voids were generated based on the generated aggregate skeleton and the assumption of equal thickness of FAM film. To prove the reliability of the model, the air voids of the digital asphalt mixture samples were verified by comparison with real specimens. The generated digital specimens were also applied to finite element method (FEM) simulations to predict the dynamic modulus of the asphalt mixture and the simulated results were in good agreement with the experimental results. The method can be applied to study the spatial distribution of asphalt mixture components, the movement pattern of aggregate particles during compaction and numerical simulations at the microscopic scale. [ABSTRACT FROM AUTHOR]

• The new Mn ferrite with low power loss at high frequencies of 1–3 MHz over a wide temperature range of 25–140 °C was successfully developed. • Power loss was divided into hysteresis loss (P hv), eddy current loss (P ev) and residual loss (P rv), and the effect of Ta 2 O 5 on each part of power loss at high frequencies was investigated. • Small content of Ta 2 O 5 segregates at grain boundaries and reduces P hv , P ev and P rv. • The mechanism of reduction of P hv , P ev and P rv by the Ta 2 O 5 addition was clarified. Dramatic increase of power loss in the MHz frequency range is the bottleneck problem for MnZn ferrites to be applied in high-frequency power electronic devices. In this work, manganese ferrites with low power loss in the frequency range of 1–3 MHz have been developed by the addition of Ta 2 O 5. The manganese ferrite with 300 ppm Ta 2 O 5 exhibits excellent P cv performance. P cv at 25 °C is as low as 41, 94 and 164 kW/m3 under measurement conditions of 1 MHz/50 mT, 2 MHz/50 mT and 3 MHz/30 mT, respectively. Excellent temperature stability of power loss in the temperature range of 25–140 °C is also achieved in this sample. Power loss was divided to three parts of hysteresis loss, eddy current loss and residual loss. Ta 2 O 5 segregates at grain boundaries and reduces all three parts of loss. The mechanism of Ta 2 O 5 influence on each part of loss has been clarified. [ABSTRACT FROM AUTHOR]

The exploration of the dependency structure of the Chinese and EU carbon trading markets is crucial to the construction of a globally harmonized carbon market. In this paper, we studied the characteristics of structural interdependency between China's major carbon markets and the European Union (EU) carbon market before and after the launch of the national carbon emissions trading scheme (ETS) and the occurrence of the new coronavirus (COVID-19) by applying the C-vine copula method, with the carbon trading prices of the EU, Beijing, Shanghai, Guangdong, Shenzhen and Hubei as the research objects. The study shows that there exists a statistically significant dependence between the EU and the major carbon markets in China and their extremal dependences and dependence structures are different at different stages. After the launch of the national carbon ETS, China has become more independent in terms of interdependency with the EU carbon market, and is more relevant between domestic carbon markets. Most importantly, we found that the dependence between the EU and Chinese carbon markets has increased following the outbreak of COVID-19, and tail dependency structures existed before the launch of the national carbon ETS and during the outbreak of the COVID-19. The results of this study provide a basis for the understanding of the linkage characteristics of carbon trading prices between China and the EU at different stages, which in turn can help market regulators and investors to formulate investment decisions and policies. [ABSTRACT FROM AUTHOR]

[Display omitted] • To evaluate the pharmacodynamic effects of SFE against streptozotocin-induced DR rats from multiple levels for the first time. • To study the distribution of flavonoids of Sophora flavescens Aiton in rat's aqueous humor and retina by UHPLC-MS. • To explore the mechanism of SFE against on DR based on untargeted retinal metabolomics. • To elucidate the effects, material basis and treatment mechanism of SFE on DR systematically. Diabetic retinopathy (DR) is the most common microvascular complication of diabetes and a leading cause of vision impairment and blindness, which lacks effective diagnostic measures and therapeutic options. Sophora flavescens Aiton or "Kushen" is a traditional Chinese medicine used since ancient times, either alone or in combination, to clear heat, dampness, and tearing, and to treat ocular diseases and improve eyesight. Additionally, the flavonoids of Sophora flavescens Aiton extracted using ethyl acetate (EtOAc) (SFE) is effective in managing diabetes and diabetic vascular complications. In this study, we explored the pharmacodynamic effects and material basis of action of SFE on DR for the first time and elucidated the mechanism based on untargeted retinal metabolomics. Results from the pharmacodynamic studies showed that SFE could reduce blood glucose levels in rats, regulate serum lipopolysaccharide, tauroursodeoxycholic acid, and trimethylamine oxide levels, and significantly improve the structure of retina in rats with DR. Moreover, SFE could protect the blood-retinal barrier, reduce angiogenesis and capillary formation, and inhibit retinal nerve cell apoptosis. A total of 13 compounds were identified in the aqueous humor and retina, which were dihydroflavonoid, isoflavonoid, pterostane flavonoid, chalcone, and dihydroflavonol derivatives. In addition, 39 differential metabolites were screened based on retinal metabolomics data and 23 were found to be affected by SFE, indicating its anti-DR effect by regulating the synthetic metabolic pathways, including lactose, bile acid, glycerophospholipid, arginine, purine, and pyrimidine metabolism pathways. Collectively, our findings elucidated the effects, material basis, and treatment mechanism of SFE on DR systematically and could lay the foundation for promoting the clinical application of Sophora flavescens Aiton. [ABSTRACT FROM AUTHOR]

Highlights: [•] Large-diameter tube-like mesoporous TiO2 was synthesized using CTAB and urea. [•] A possible mechanism for the formation of tube-like mesoporous TiO2 was proposed. [•] Tube-like TiO2 was suitable for photodegradation of papermaking wastewater. [•] Tube-like TiO2 showed much higher photocatalytic activities than Degussa P25. [ABSTRACT FROM AUTHOR]

With the rapid global urbanization, the unlimited increasing transportation infrastructure has met the needs of urban expansion, but it has caused a series of ecological problems lacking consideration of ecological conservation. The land suitability assessment for supporting transport planning based on carrying capacity and demand for construction is an effective way to promote urban socioeconomic development and ecological conservation. Therefore, we constructed a logical framework of resources and environment supporting, traffic construction demand driving, and ecological protection red line and basic farmland constraining, and applied the analytic hierarchy process (AHP), GIS, three-dimensional magic cube method, and gravity model to evaluate the suitability of expressway development in Sichuan Province, China. The results showed that the spatial difference in the carrying capacity of resources and environment and the demand for expressway construction was relatively high in Sichuan, and those in eastern cities were even higher. The land suitability for supporting transport planning was relatively high, and the suitable areas with a grade from 8 to 10, accounted for 20.77% of the total study area, which could almost meet the demand for transportation infrastructure construction. The land suitability performed a circle structure with Chengdu as the core and gradually decreasing to the periphery. Overall, this study adds new insights to transport planning reform in other similar regions around the world and can provide important references for regional development planning and environmental protection. [ABSTRACT FROM AUTHOR]

To develop a full-biodegradable thermoresponsive polymer with a wide temperature range, a hydrophilic, biodegradable and biocompatible thermoresponsive polymer having a polylactide backbone polymer and a side chain norbornene group was synthesized by ring-opening polymerization of a norbornene-functionalized lactide, followed by graft of backbone polymer with polyethylene glycol monomethyl ether (MPEG) and modification with isopropylamide (IPA), the latter of which critically influences the phase transition temperature of the copolymer. The effects of polymerization degree (DP), molecular weight of MPEG, the proportion of MPEG and IPA, and the concentration of polymer on the behaviors of the thermoresponsive polymer solution were systematically studied. The Cp ranged from 32 to 72 °C, and it was found that higher number of the MPEG moiety led to higher Cp, whereas the longer isopropylamide group resulted in lower Cp. It is noteworthy that with the unique characteristics, thermosensitivity at body temperature, biodegradability, and a well-defined copolymer structure, the developed thermoresponsive polymer is promising for biomedical applications as an essential material. Unlabelled Image [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive system for assessing contaminant emissions, including the dominant contaminant reduction effects, recessive contaminant reduction effects, and contaminant reduction efficiency indexes. The system is used to evaluate the linkage changes in contaminant emissions reduction across different sectors, the ease of regulation, and the returns on emissions reduction efforts. The study's results demonstrate that firstly, COVID-19 initially reduced contaminant emissions across almost all sectors, although this effect waned over time. Secondly, applying conventional regulatory measures to sectors with high reductions in contaminant emissions may not yield the expected results. Thirdly, while some sectors may be more difficult to regulate, they may offer a higher return on investment in terms of emissions reduction. Based on the above results, the paper advocates for timely measures to consolidate environmental gains, prevent rebounding of contaminant emissions, prioritize supervision and management of easily regulated sectors, prioritize upgrading of cleaner production in sectors with high reduction efficiency indices, and increase investment in environmental technology. • Created a new comprehensive system for assessing contaminant emission changes. • Quantified the unique linkage changes of contaminant emissions during COVID-19. • Developed new models to reveal contaminants' regulatory difficulty and return. • The innovative reduction effects of four key contaminant indicators were measured. • Applied WHEM firstly in research across multiple areas of contaminant emissions. [ABSTRACT FROM AUTHOR]