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In order to slow down the cooling rate of mixture and reduce the low-temperature cracking of asphalt pavement in large temperature difference areas, polyurethane solid–solid low-temperature phase change materials (PSLPCMs) were prepared by prepolymer method in this study. The PSLPCMs were incorporated into hot mix asphalt mixture to prepare PSLPCMs particle asphalt mixture. The pavement performance and phase change temperature control behavior of this special type of mixture were analyzed from the perspectives of particle content and particle size. Studies have shown that PSLPCMs have good phase change thermal storage performance and thermal stability. Different PSLPCMs content and particle size have certain improvement effect on the high temperature stability and low temperature crack resistance of the mixture, and have no obvious adverse effect on the water stability of the mixture. At the same dosage, with the increase of particle size, the improvement effect of PSLPCMs particles on the road performance of the mixture is more obvious. With the increase of PSLPCMs particle content, the specific heat capacity of asphalt mixture increases, and the thermal conductivity decreases. The temperature regulation effect of asphalt mixture shows an increasing trend, and the cooling rate slows down. The PSLPCMs particles with particle size of 1.18–2.36 mm have better improvement effect on the temperature regulation performance of the mixture. When the content of PSLPCMs is 7 wt%, the maximum temperature regulation effect of the mixture reaches 3.4 °C.

We study a Monge-Ampère type equation that interpolates the classical {σ_2} -Yamabe equation in conformal geometry and the 2-Hessian equation in dimension 4., 37 pages

Liquid metal (LM) has shown potential values in different areas. Attempts to implement LM are tending to develop new functions and make it versatile to improve its performance for practical applications. Here, we present an unprecedented LM-integrated ultra-elastic microfiber with distinctive features for wearable electronics. The microfiber with a polyurethane shell and an LM core was continuously generated by using a sequenced microfluidic spinning and injection method. Due to the precise fluid manipulation of microfluidics, the resultant microfiber could be tailored with tunable morphologies and responsive conductivities. We have demonstrated that the microfiber could act as dynamic force sensor and motion indicator when it was embedded into elastic films. In addition, the values of the LM-integrated ultra-elastic microfiber on energy conversions such as electro-magnetic or electro-thermal conversions have also been realized. These features indicate that LM-integrated microfiber will open up new frontiers in LM-integrated materials and the wearable electronics field.

We revisit faithfully balanced modules. These are faithful modules having the double centralizer property. For finite-dimensional algebras our main tool is the category ${\rm cogen}^1(M)$ of modules with a copresentation by summands of finite sums of $M$ on which ${\rm Hom}(-,M)$ is exact. For a faithfully balanced module $M$ the functor ${\rm Hom}(-,M)$ is a duality on these categories - for cotilting modules this is the Brenner-Butler theorem. We also study new classes of faithfully balanced modules combining cogenerators and cotilting modules. Then we turn to relative homological algebra in the sense of Auslander-Solberg and define a relative version of faithfully balancedness which we call $1$-$\mathbf{F}$-faithful. We find relative versions of the best known classes of faithfully balanced modules (including (co)generators ,(co)tilting and cluster tilting modules). Here we characterize the corresponding modules over the endomorphism ring of the faithfully balanced module - this is what we call a \emph{correspondence}. Two highlights are the relative (higher) Auslander correspondence and the relative cotilting correspondence - the second is a generalization of a relative cotilting correspondence of Auslander-Solberg to an involution (as the usual cotilting correspondence is)., Comment: 37 pages. v2: Some typos have been fixed, including the incorrect statements in Theorem 1.3 and Theorem 1.4

A novel free-standing electrode consisting of nickel phosphide (Ni2P) nanoparticles on nitrogen and phosphorus co-doped porous carbon (NPC) are synthesized on carbon cloth (CC). Polyaniline (PANI) and nickel (Ni) are sequentially electro-deposited on the surface of CC, which are then transformed into NPC and Ni2P by an in-situ carbonization-phosphorization combined process. The electrode surface is distributed with large amounts of uniform macropores, which could expose more active sites and enhance the interfacial exchange with the electrolyte. The Ni2P@NPC@CC electrode delivers early overpotentials of 92 and 280 mV vs. Reversible Hydrogen Electrode (RHE) at 10 mA cm−2 for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline condition, respectively. The electrolytic cell with Ni2P@NPC@CC electrode both as anode and cathode can achieve 10 mA cm−2 at a small bias of 1.54 V for the overall water splitting. Density functional theory (DFT) calculation indicates that combination with Ni2P and NPC can decrease Gibbs free energy for H* adsorption (ΔGH*) and increase charge density on the interface, thus could lead to the enhanced activity for water splitting. The free-standing and noble-metal free Ni2P@NPC@CC electrode is stable, highly active and cost effective, thus have great potential for the hydrogen production.

Dissimilar joining of 6 mm thick steel/Al butt joints was carried out using a novel laser offset welding process. The effect of the different locations at the interface on the intermetallic compound (IMC) layers of the joints produced by two different laser powers was investigated. Microstructure inhomogeneity of the IMC layers was investigated in terms of phase morphology, thickness, grain size, main component and phase compositions. As a result, the IMC layer at the interface has the same phase types consisting of η-Fe2Al5 and θ-Fe4Al13 phase for the three locations produced by two laser powers. However, the morphology of the θ-Fe4Al13 phases, the grain size and the thickness of the η-Fe2Al5 layers, and the predominant component in the IMC layers is strongly affected by the laser powers and the locations at the interface. The highest UTS of 85.5 MPa is obtained at the middle location due to the formation of the thinner η-Fe2Al5 layers and the minimum amount of θ-Fe4Al13 phases. Decreasing laser energy inputs effectively improves the IMC layer uniformity, and the influence of locations at the interface on the IMC layer thickness will be weakened with further decreasing the energy inputs. The heating temperature at the interface has a very important impact on the thickness of the η-Fe2Al5 layer attributed to the ferrite or austenite phases appeared in the steel substrate affecting the growth rate of the η-Fe2Al5 layers.

The calcium-activated chloride channel, also known as TMEM16A, shows both calcium and membrane potential dependent activation. The channel is expressed broadly and contributes to a variety of physiological processes, and it is expected to be a target for the treatment of diseases such as hypertension, pain, cystic fibrosis and lung cancer. A thorough understanding of the structural characteristics of TMEM16A is important to reveal its physiological and pathological roles. Recent studies have released several Cryo-EM structures of the channel, revealed the structural basis and mechanism of the gating of the channel. This review focused on the understandings of the structural basis and molecular mechanism of the gating and permeation of TMEM16A channel, which will provide important basis for the development of drugs targeting TMEM16A.

Polyurethane solid–solid phase change material (PCM) with low phase change temperature is synthesized via prepolymer method. The synthetic polyurethane solid–solid PCM had lower crystallinity than PTMEG2000. The polyurethane solid–solid PCM was still in solid state during the heating process, and no liquid leakage was observed. After many phase change cycles, the polyurethane solid–solid PCM exhibited good stability of phase change cycles. Hence, the asphalt modified by polyurethane solid–solid PCM was prepared by high-speed shearing method. With increasing polyurethane solid–solid PCM proportion, the high temperature deformation resistance of modified asphalt gradually increased. At low temperature ( 3 wt%, the specific heat capacity of the modified asphalt had an evident peak ranging from 13 °C to 25 °C. In the range of the proportion, the coefficient of the heat conductivity of the modified asphalt gradually increased with increasing PCM content. During the cooling process, the modified asphalt cooled relatively slow before the phase transition of the polyurethane solid–solid PCM. With continued decrease in the temperature, the phase transition of the polyurethane solid–solid PCM occurred, and the cooling rate of the modified asphalt further decreased. With increasing polyurethane solid–solid PCM content, the temperature control ability of modified asphalt and the efficiency of temperature control gradually increased.

Although some established electromagnetic particle detectors have been used to detect and distinguish micro-particles in different fields, the adopted particle equivalent model leads to large detection error because that ignores the difference of the magnetic perturbations induced by particles with different shapes and postures. To improve the development of high-precision electromagnetic micro-particle detectors, the magnetic models of particles with different shapes and postures are established. The distribution of magnetic flux density and the magnetic energy change caused by particles are calculated. The theoretical and experimental results illustrate that the change of magnetic energy caused by spherical particles is much lower than that caused by ellipsoidal and flaky particles of the same volume, meanwhile, with the increase of the rotation angle of ellipsoidal and flaky particles, the variation of magnetic energy decreases significantly. Based on the results, precise particle equivalent functions considering the magnetic properties of particles are proposed.

To analyze the latent heat thermoregulation effect of the microencapsulated phase change material (Micro-PCM) on the pavement asphalt mixture, 300 mm × 300 mm × 300 mm outdoor cubic specimen made up of asphalt mixture with the Micro-PCM was prepared. By arranging a sufficient number of temperature sensors inside the specimen, a real-time monitoring system was established to record the temperature variations of the specimen. Two indices, the latent heat accumulated temperature value (LHATV) and latent heat thermoregulation index (LHTI) were proposed to evaluate the latent heat thermoregulation performance of the Micro-PCM under heating and cooling processes. The results showed that the solar radiation and air flow conditions were the important factors affecting the latent heat effect of the Micro-PCM. The responses of the heat transfer process of the Micro-PCM varied at different locations inside the specimen, which caused a difference in the latent heat efficiency. Meanwhile, under the conditions where the ambient temperature changed rapidly, the phase change response inside the specimen would be relatively lagged, the process of latent heat storage was hindered, and the heat couldn’t be completely converted to the latent form. It can be conclude that the excessive heating and cooling rates will affect the process of latent heat, the thermoregulation efficiency of the Micro-PCM can be maintained at a high level under the appropriate variable temperature conditions, a medium temperature range and time span. Under these conditions, the Micro-PCM can exert an effective latent heat thermoregulation function to asphalt mixture.

Phase change material is a high thermal storage substance, which can reduce temperature-related diseases of asphalt pavement when mixed with asphalt mixture. In this paper, NiTi alloy phase change heat-storage asphalt mixture (NiTi APCHAM) are prepared by using equal volume parts to replace fine asphalt aggregates partially with the NiTi alloy phase change energy-storage particles (NiTi APCEP). As the temperature increases, the specific heat capacity of NiTi APCHAM will increase first and then decrease due to the heat-storage effect of NiTi APCEP. The thermal conductivity coefficient of NiTi APCHAM shows a linear increasing trend with the increase in the substitution rate of NiTi APCEP. Adding NiTi APCEP in asphalt mixture can reduce its daily maximum temperature. Increasing admixture of NiTi APCEP in asphalt mixture can help to improve the phase change heat-storage thermoregulation capacity of the mixture. However, at a 6 wt% substitution rate of NiTi APCEP, the latent heat thermoregulation efficiency of NiTi APCEP reaches to maximum. With the increase in the content of NiTi APCEP, the Marshall stability of asphalt mixture gradually increases, and flexural-tensile strain at low temperature decreases gradually. By contrast, the water stability of the asphalt mixture is unaffected by the addition of NiTi APCEP.

A “one stop” thermal stabilizer, zinc arginine complex (Zn(Arg) 2 ), with excellent excellent initial whiteness, whiteness retention and long-term thermal stability time for PVC, was conveniently synthesized in water solution. The successful synthesis of Zn(Arg) 2 was confirmed by FTIR, TGA and element analysis. Besides the longer Congo red and static thermal stability time than nitrogen-containing thermal stabilizer reported, Zn(Arg) 2 also had better initial whiteness, whiteness retention and dynamic thermal stability time showed by Congo red test, discoloration test and torque rheology test. Especially, the static thermal stability time was more than 150 min, and the dynamic thermal stability time reached 78 min. The excellent thermal stability effect of Zn(Arg) 2 on PVC was ascribed to the simultaneous possession of three mechanisms: absorbing HCl, replacing labile chlorine atoms and complexing ZnCl 2 . Moreover, PVC with Zn(Arg) 2 also showed excellent transmittance tested by vis-uv-near infrared spectrophotometer. Therefore, Zn(Arg) 2 is a “one stop” thermal stabilizer with good application prospects in transparent PVC.

The comprehensive fault diagnosis method has been developed to analyze the failure of the multi-disc clutch. The mechanical buckling model is developed to investigate the relationship between the resistance torque and the periodic circumferential bright spots. The contact pressure and temperature on the friction surfaces are obtained with the consideration of the concentrated reactive load of the circlip. The friction and wear characteristics of the friction disc under different temperature conditions are explored by the pin-on-disc test, and then the surface morphologies of tested discs are observed by the metalloscope. The results demonstrate that both the thermal buckling and the mechanical buckling can result in the mechanical-thermal buckling. As the temperature varies from 15 °C to 400 °C, the disc experiences the abrasive wear, ploughing wear, adhesive wear and delamination wear in order. Finally, the mechanical-thermal safety boundaries are proposed. Moreover, the paper provides some suggestions for better design of clutch: the circlip should be optimized to avoid stress concentration; the teeth number of separate plates should be increased to improve the torque transmission capacity; the thickness of separate plates should be different which can be determined by their axial positions in the clutch pack.

A totally new theory of “two-step stabilization mechanism” for triazole-based zinc-containing complex (abbreviated as [Zn(ttr)(OAc)]) was proposed through several designed experiments. [Zn(ttr)(OAc)] strongly absorbed HCl at the beginning, and then broke down into 3-amino-1,2,4-triazole which could further stabilized PVC. The structure of [Zn(ttr)(OAc)] was characterized by FTIR spectroscopy, elemental analysis and SEM. Then, Congo red tests and discoloration tests verified [Zn(ttr)(OAc)] could absorb HCl effectively, but PVC showed poor initial whiteness, which further proved above-mentioned stabilization mechanism. Moreover, [Zn(ttr)(OAc)] combined with ZnSt2 and dibenzoyl methane (DBM) effectively improved the initial color of PVC samples and provided PVC with shorter plasticizing time and longer dynamic thermal stability time than commercial stabilizer 1086F, confirmed by discoloration tests and dynamic thermal stability analysis. We believe [Zn(ttr)(OAc)]/ZnSt2/DBM stabilizer system can be used as a commercial stabilizer and the stabilization mechanism of [Zn(ttr)(OAc)] may provide a new way to stabilize PVC.

Early Triassic marine ecosystems experienced multiple environmental perturbations and a delayed biotic recovery following the end-Permian mass extinction. The Smithian–Spathian boundary (SSB), in the late Early Triassic, marks a major shift toward a less intensely warm climate, ameliorated marine environmental conditions, and the onset of a more sustained recovery of marine faunas. Accumulating geochemical evidence indicates that these developments were accompanied by large changes in global-ocean circulation during the Smithian–Spathian (S–S) transition. In the present study, tandem carbon and sulfur isotopic records were used to investigate changes in the marine carbon and sulfur cycles across the SSB and their potential relationship to global-ocean circulation changes. First, we conducted a carbon‑sulfur isotope study at two deepwater SSB sections (West Pingdingshan and Jiarong) in South China. High-resolution δ13Ccarb-δ34SCAS profiles show large positive excursions and strong correlations through the S–S transition, suggesting control by co-burial of organic matter and pyrite. Second, we reviewed global carbon‑sulfur isotope studies through the Smithian and Spathian substages. Similar to carbonate carbon isotopes, sulfate sulfur isotopes also show vertical gradient changes during the S–S transition. We link these changes to an expansion of oceanic oxygen-minimum zones (OMZs) in response to a cooling-driven re-invigoration of global-ocean circulation that triggered enhanced productivity on platform margins. OMZ expansion may have contributed to a second-order extinction among conodonts and ammonoids at the SSB, but the long-term shift toward more vigorous ocean circulation and better-ventilated watermasses is likely to have facilitated the overall recovery of marine biotas during the Spathian Substage of the late Early Triassic.

In this work, Ti-Sn-Sb/γ-Al2O3 particle electrodes were prepared and employed for the degradation of oxytetracycline (OTC) by three-dimensional electrocatalytic technology. Factors associated with the preparation of Ti-Sn-Sb/γ-Al2O3 particle electrodes were investigated. The effects of initial concentration, conductivity, pH value, aeration intensity, current density, plate spacing, and particle electrode dosage on OTC removal were studied. The removal rate of OTC and total organic carbon were achieved approximately 92.0% and 41.0% under the optimal operating condition, respectively. In addition, Ti-Sn-Sb/γ-Al2O3 particle electrode was analyzed by Fourier Transform Infrared spectroscopy (FT-IR), scanning electron microscope (SEM), energy dispersive spectrum analysis (EDX), X-Ray Fluorescence Spectrometer (XRF), and X Ray Diffraction analysis (XRD), which indicated that a significant amount of TiO2, SnO2, and Sb2O3 were formed on the surface of Ti-Sn-Sb/γ-Al2O3 particle electrode. It was also observed that the primary function of Ti-Sn-Sb/γ-Al2O3 particle electrode in the three-dimensional electrode electrolysis process is the strong oxidizing function of ·OH for degrading OTC. Consequently, the analysis of degradation products of oxytetracycline (OTC) demonstrates. In addition, the results and conclusions of this study provide a methodological basis and engineering practice basis for removing the low concentration of antibiotics in water.

Shared control structure is beneficial to steering controller design of intelligence vehicles, and human-machine goal consistency is a key prerequisite for shared control. However, the goal consistency is usually given and cannot be changed, and the steering controller in low goal consistency, which directly affect the vehicle performance in case of emergency, has not been sufficiently investigated. This paper proposes a shared steering controller for path-following task based on Nash game strategy and steer-by-wire system considering different human-machine goal consistency. The driver-automation interactive path-following task is modeled by non-cooperative MPC, and authority weight of lateral displacement is used to balance the control objectives of the driver and automation. Human-machine goal consistency is determined by the driver and the automation controller steering angle. Aimed at different goal consistencies, a continuous authority weight adjustment algorithm is designed to ensure correct path following. This is especially true in low consistency in this study, when four driving modes are given to meet the different demand for control power. Simulations and hard-in-loop tests are conducted to verify the proposed control algorithm and the results show that it can perform the path-following task irrespective of human-machine goal consistency.

Phase change materials (PCMs) can effectively adjust the temperature of asphalt pavement and have broad application prospects. Microencapsulated phase change materials (micro-PCMs) can solve the leaking problem of PCMs, which easily occurs during the heating process of the asphalt mineral mixture. This paper is intended to provide two indices to evaluate the temperature regulation effect of micro-PCMs: the latent heat accumulated temperature value (LHATV) and latent heat thermoregulation index (LHTI). The LHATV reflects the thermal regulation capability of micro-PCMs and the accumulation in temperature difference in a certain time range. The LHTI represents the completion degree of latent heat in unit time and unit temperature, and it reflects the efficiency of latent heat thermoregulation. The outdoor cube model test was conducted on two cube models with dimensions of 30 cm × 30 cm × 30 cm. Each cube model consisted of three asphalt specimens with dimensions of 30 cm × 30 cm × 10 cm. The first cube model, which was mixed with 0.3% wt of micro-PCMs, served as the experimental group, and the other cube model without micro-PCMs addition served as the control group. Inside the two cube models, sufficient temperature sensors were placed to monitor the temperature. The analysis results show that there is a transformable relationship between the latent heat time domain and the temperature domain. In the moderate temperature range and time span, the latent heat thermal stabilization of micro-PCMs can be efficient.

The Kamura section, located in the Chichibu Belt of Kyushu Island in southern Japan, contains a succession of uppermost Permian to Upper Triassic shallow-marine atoll sediments from the mid-Panthalassic Ocean. In the present study, carbonate microfacies, conodont biostratigraphy, and carbonate carbon isotopes were analyzed, making it possible to construct a detailed biochronological framework for the Triassic of the central Panthalassic region. A total of 14 conodont zones are recognized from the uppermost Changhsingian to the upper Norian. The Lower Triassic contains the Hindeodus parvus, Isarcicella isarcica, and H. postparvus zones (Griesbachian), the Neospathodus dieneri Zone (Dienerian), and the Novispathodus ex gr. waageni-Parachirognathus Zone (Smithian), while no evidence of the upper Lower Triassic Spathian substage was recovered at Kamura. The overlying Middle Triassic section consists of the Chiosella ex gr. timorensis-Cratognathus, ‘Paragondolella’ ex gr. alpina-Pg. ex gr. excelsa, Budurovignathus hungaricus, and B. mungoensis zones, followed in the Upper Triassic by the Quadralella tadpole-Gladigondolella malayensis, Q. lobata-Q. carpathica, Primatella cf. orchardi-Pr. permica, Epigondolella rigoi-‘Pg.’ hallstattensis, and E. ex gr. bidentata-Norigondolella steinbergensis zones. The exact stratigraphic intervals present at Kamura were refined through intercalibration of the conodont biozonation data with its δ13Ccarb profile, which shows a characteristic series of negative and positive excursions that correspond to well-established global reference profiles. The Permian–Triassic boundary is placed 0.20 m above the Mitai-Kamura formation contact (a reference datum corresponding to the end-Permian extinction horizon, = 0 m) based on the first appearance of H. parvus, and the Olenekian–Anisian boundary is placed 17.60 m above the reference datum based on the first appearance of Ch. ex gr. timorensis. Kamura carbonates were assigned to six fabric types and 17 microfacies. The microfacies succession records a deepening immediately following the end-Permian mass extinction, a strong shallowing during the mid to late Smithian, development of an unconformity spanning the entire Spathian, and minor sea-level fluctuations during the Middle and Late Triassic. The Spathian unconformity is attributed to a eustatic fall related to a sharp cooling event at or close to the Smithian–Spathian boundary that exposed the Kamura atoll. The subsequent resumption of shallow-marine sedimentation in the earliest Middle Triassic was probably due to continued thermal subsidence of the oceanic crustal basement beneath the atoll. The present work is the most complete analysis to date of the conodont biostratigraphic, carbon isotope chemostratigraphic, and eustatic records of the Triassic System in the central Panthalassic Ocean and should serve as a regional reference standard in the future.

Bronze is one of copper alloy materials that have been widely used not only in the Bronze Age, but also nowadays because they are hard, easy to cast and resistant against corrosion. For bronze, tin is commonly used as the major non-copper ingredient of bronze because of many highly desirable characteristics including the fact that metallic tin is not toxic. We find that the tin bronze is a suitable electrode material for non-enzymatic electrochemical glucose sensing in saliva. For electrocatalytic oxidation of glucose on the bronze electrode, a negative potential is applied for proton reduction which creates a temporary alkaline condition. The sensor has a linear range from 0 to 320 μM with the regression equation: i = 11 + 0.015 C (i is the current in μA and C is the concentration in μM) with a correlation coefficient of 0.994. The sensitivity is found to be 480 μA mM−1 cm-2, and the detection limit is 6.6 μM with a signal-to-noise ratio of 3. The electrode is found to be highly selective towards glucose oxidation in the presence of interfering species such as ascorbic acid and uric acid. The electrochemical senor is integrated into a smart toothbrush for monitoring of saliva glucose, which is potentially useful for non-invasive screening of diabetes. Compared with other electrochemical glucose sensors, a naked bronze electrode is used as the working electrode to ensure the robustness of the sensor. No additional reagent is involved for the electrochemical determination of saliva glucose and the electrode can be regenerated simply by mechanically polishing for long-term uses.

A coupled numerical multi-physics model is developed to study the generation and variation mechanisms of friction torque, including fluid lubricating, micro-contact, sliding and heat transfer among the friction components. The engagement experiment is conducted to verify the accuracy of numerical model and investigate the stability of friction torque. The results show that the most significant operating factor affecting the friction stability is the applied pressure, followed by the rotating speed and the ATF temperature. Simultaneously, the operating factors have great influence on the torque response, engagement time and temperature rise. Moreover, the growth model of friction torque can be divided into two categories: one is increasing linearly and the other is concave parabolic rising.