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Low‐permittivity ZnAl2‐x(Zn0.5Ti0.5)xO4 ceramics were synthesized via conventional solid‐state reaction method. A pure ZnAl2O4 solid‐state solution with an Fd‐3m space group was achieved at x ≤ 0.1. Results showed that partial substitution of [Zn0.5Ti0.5]3+ for Al3+ effectively lowered the sintering temperature of the ZnAl2O4 ceramics and remarkably increased the quality factor (Q × f) values. Optimum microwave dielectric properties (εr = 9.1, Q × f = 115,800 GHz and τf = −78 ppm/°C) were obtained in the sample with x = 0.1 sintered at 1400°C in oxygen atmosphere for 10 h. The temperature used for the sample was approximately 250°C lower than the sintering temperature of conventional ZnAl2O4 ceramics. [ABSTRACT FROM AUTHOR]

Microwave dielectric properties of low-permittivity LiAl1−x(Mg0.5Si0.5)xO2 (LAMS) (x = 0.02–0.2) ceramics synthesised through solid-state reaction route were investigated. All compositions show pure LiAlO2 phase with a P41212 space group at x ≤ 0.18. Microstructure and relative permittivity (εr) were greatly affected by the partial substitution of [Mg0.5Si0.5]3+ for Al3+ site. Bond energy decreased with increasing x value, thereby increasing the temperature coefficient of resonant frequency (τf) in the negative direction. Finally, the optimum microwave dielectric properties of LAMS (x = 0.02) sample were obtained at 1300 °C with εr = 6.17, Q × f = 53,300 GHz and τf = − 129 ppm/°C. Then CaTiO3 was added to the LAMS (x = 0.02) material to adjust the τf value to near zero. [ABSTRACT FROM AUTHOR]

It has been found that the traffic speed is most direct reflection of traffic state. The speed of individual vehicle, however, is inadequate to estimate accurately actual traffic status. Thereby the speeds from several vehicles should be aggregated in order to arrive at a good approximation of actually travel speed for total traffic. In this paper, with the GPS data, a series of technologies are combined with the geographic information systems for transportation map to compute the road average-speed, which is computed by aggregating all of the instantaneous speeds in interested road section. And after that, an evaluation index of traffic situations is introduced to estimate the real traffic state based on the road average-speeds and free-flow speeds. At same time, some key factors influencing traffic state are considered in order to get more accurate estimations. The illustration and experimental results indicate that the proposed method can characterize the actual traffic speeds well and provide an accurate estimation of traffic state. [ABSTRACT FROM AUTHOR]

Gear hobbing is the use of machinery to manufacture external gears. With the booming motor industry, there are more requirements for gear hobbing accuracy than ever before. Thermal error – as a major source of error in a dry hobbing machine – must be effectively compensated to achieve accuracy. Thus, studies on the thermal error of hob assembly are important both in theory and practice. This paper discusses the development of a valid numerical modelling method for the hob assembly of a dry hobbing machine. The equations used to determine the values of heat sources and heat transfer coefficients are given. The temperature field and thermal deformation of the hob assembly were obtained by thermal-structural coupling numerical simulations. Numerical results showed that the deformation can maximally reach to 94.5 µm, which is non-ignorable in the thermal deformation analysis of the whole dry gear hobbing machine. Subsequently, by comparing the simulation results and experimental data, the newly proposed method to determine the forced convection heat transfer coefficient proved more fitting for describing the airflow pattern inside the gear hobbing zone. The satisfactory agreement between simulation results and experimental data also suggests that the numerical analysis method proposed in this paper can provide an effective research tool to optimize the design of hob assembly. And the results obtained by the proposed method can be used for thermal error modelling in real error compensation. [ABSTRACT FROM AUTHOR]

Alcoholic liver disease (ALD) is a progressive liver disease that can cause a series of complications, including cirrhosis, liver failure and hepatocellular carcinoma. Granulocytic myeloid‐derived suppressor cell (gMDSC) populations have been observed to expand in various liver diseases and to inhibit innate and adaptive immunity in patients with liver disease. However, the characteristics of gMDSCs in patients with ALD have not been studied. We studied 24 healthy controls (HCs) and 107 patients with ALD and found an accumulation of gMDSCs in the peripheral blood of patients with alcoholic liver cirrhosis (ALC). Furthermore, ALC patients with a poor prognosis displayed a significant increase in peripheral gMDSCs and showed an increased capacity for arginase I production compared to HCs. In contrast, plasma arginase I levels in ALC patients were negatively correlated with total bilirubin and international normalized ratio, two key parameters of liver damage. Importantly, gMDSCs accumulated in the livers of ALC patients, and the frequency of liver gMDSCs significantly correlated with that of peripheral gMDSCs. In addition, gMDSC enrichment in vitro significantly inhibited the function of natural killer (NK) cells, perhaps preventing the NK‐induced apoptosis of hepatic stellate cells. In summary, increased peripheral and intrahepatic gMDSC populations are present in patients with ALC and may contribute to enhancing the severity of liver cirrhosis. [ABSTRACT FROM AUTHOR]

Dry hobbing machine is a kind of specialized machine tool to manufacture high-quality small-module gears. With the development of shipbuilding, automobile, and wind power industries, higher request on the dry gear hobbing accuracy is called. The thermal-induced error, which accounts for 50-70% of machining error, needs to be reduced more efficiently. Hence, in-depth investigation on the thermal-structural characteristics of the dry hobbing machine is indispensable. In this paper, thermal-structural coupling numerical simulations were conducted to investigate the heat transfer process as well as thermal-induced deformation of the worktable of a YDE3120CNC gear hobbing machine in the large-volume gear production. New equations were used here to describe the convection heat transfer happened on the worktable assembly. Verifying test results proved the feasibility of the newly proposed numerical method. Following numerical simulation, results indicated that during the gear hobbing process, the highest surface temperature of the worktable assembly appeared at the top surface of the fixture, and corresponding thermal-induced deformation reached the maximum of 49.9 μm. Besides, in a large-volume production, the worktable assembly would attain thermal equilibrium in 15,000 s. Hence, the assumption widely used in previous studies on gear hobbing machines that the worktable assembly could be treated as an ideal solid without any thermal deformation is wrong. The thermal-induced deformation of the worktable assembly should be considered in the subsequent development of the thermal error compensation system. [ABSTRACT FROM AUTHOR]

[Display omitted] • Citric acid promoted hydrogen corrosion of zero valent iron for methane production. • Zero valent iron and citric acid increased methane production potential by 63.8%. • Hydrogen accumulation with zero valent iron and citric acid were the highest. • Ferrous ions increased to 2.32 times higher than that with solo zero valent iron. • Hydrogenotrophic methanogens enriched while acetotrophic methanogens reduced. Anaerobic digestion of waste activated sludge (WAS) for biofuel recovery is one key step for developing energy-self-sufficient and carbon–neutral wastewater treatment plants. Although zero valent iron (ZVI) is an alternative additive to promote methane production from WAS, low hydrogen corrosion of ZVI is one important limitation. This study explored whether methane production potential could be further enhanced while using citric acid (CA) to accelerate hydrogen corrosion of ZVI. Results showed that the maximum methane production reached 92.77 mL/g volatile suspended solid (VSS) with ZVI of 30 mM and CA of 6 mM, which increased by 63.8% compared to that with solo ZVI. Mechanism analysis demonstrated that the proposed strategy could accelerate the solubilization of WAS, increase the accumulation of short-chain fatty acids (SCFAs), and optimize the composition of SCFAs. Meanwhile, both the efficiencies of hydrogen yield and production rate obtained with ZVI and CA were the highest. The accumulation of hydrogen with ZVI and CA reached 5 mL/g VSS during the 9-hour period, which was 2.42 times higher than that with solo ZVI, and the hourly hydrogen production rate was 2.47 mL/g VSS−1h−1, which was higher than those with either solo CA or ZVI. Thus, the effectiveness of 1 + 1＞2 was obtained. Correspondingly, the concentration of ferrous ion with ZVI and CA increased to 2.32 times higher than that with solo ZVI. In addition, the microbial community analysis indicated that hydrogenotrophic methanogens were predominated with ZVI and CA. These findings may provide some new solutions for promoting the role of nano-ZVI in enhancing methane production from anaerobic digestion. [ABSTRACT FROM AUTHOR]

Injectable antibacterial hydrogels have attracted considerable attention in wound management. However, the development of injectable hydrogels with excellent antibacterial activity, good biocompatibility, and strong tissue adhesion remains a challenge. In this study, an antibacterial tissue-adhesive hydrogel was developed based on a catalyst-free o -phthalaldehyde (OPA)/amine reaction by simply mixing OPA-terminated four-arm poly(ethylene glycol) (4aPEG-OPA) and ε-poly- l -lysine (ε-PLL) solutions. The hydrogel showed tunable gelation time, storage moduli, and degradation rate depending on the polymer concentration and 4aPEG-OPA/ε-PLL mass ratio. The hydrogel exhibited nearly 100% bacterial inhibition rates in-vitro against Gram-negative E. coli and Gram-positive S. aureus , while maintaining good biocompatibility. The hydrogel matched well in shape and tightly adhered to the tissue after in-situ formation at the wound sites. Following the treatment of rat models of full-thickness skin incisions and round wounds, the hydrogel effectively closed the wounds and promoted wound healing. Moreover, after administering to S. aureus infected full-thickness skin wounds, the hydrogel exhibited remarkable efficacy in inhibiting wound infection with a bacterial inhibition rate over 99.94%, achieving a significantly accelerated wound healing compared with the commercially available Prontosan® gel. Therefore, the hydrogel exhibits great potential as a wound dressing for infection prevention and promotion of healing. [ABSTRACT FROM AUTHOR]

Ba1+1/ M[Si2O5+1/ M] low-permittivity microwave dielectric ceramics are prepared using the conventional solid-state method. Pure phases are obtained in barium silicates with M = 1, 3, 4, 5, and ∞, except for M = 7, in which two phases, Ba5Si8O21 and BaSi2O5, are observed. As the complexity of the crystal structure described by the Shannon information per reduced unit cell increases, the τf value tends to change from a negative to a positive value, except for M = 5, which has the highest complexity. A single Ba5Si8O21 phase with εr anomaly peak at −180°C exhibits a rare positive τf value (+25 ppm/°C), which is a novel temperature compensator. [ABSTRACT FROM AUTHOR]

This study aims to utilize the hybrid solid-state LiDAR (SSL) point cloud to achieve pavement 3D reconstruction and overcome the stratification problem of the pavement point cloud. A low-cost Mobile Laser Scanning (MLS) system based on the hybrid SSL is constructed beforehand. Then, a region of interest (ROI) extraction algorithm is designed to filter the useless point cloud. Finally, a plane-based global registration (PGR) approach is proposed to address the stratification problem of vertical direction. PGR includes two parts: coarse registration and refined registration. The coarse registration extracts the pavement plane to reduce the vertical error. The refined registration utilizes the Iterative Closest Point (ICP) algorithm to reduce the registration error further. Compared with the mainstream registration algorithms, PGR shows the highest registration accuracy in different road scenarios and maintains excellent real-time performance. Furthermore, the reconstruction accuracy is kept within 1 cm, sufficient to extract pavement information. • Hybrid solid-state LiDAR (SSL) point cloud for pavement 3D reconstruction. • Useless point cloud filtering using region of interest (ROI) extraction algorithm. • Plane-based global registration (PGR) to improve reconstruction accuracy. • High-quality point cloud acquisition using a low-cost and lightweight MLS system. [ABSTRACT FROM AUTHOR]

In this paper, an overview focusing on the bond behavior of recycled coarse aggregate concrete (RAC) with steel bar is carried out. The results show that the failure modes of RAC specimen were not only influenced by a single factor, it is necessary to comprehensively consider the influence of various factors on the failure modes of RAC specimen; The steel bar diameter, the concrete cover to diameter ratio and the replacement rate of RCA all affect the load-slip curve of RAC specimen; Bond strength predictive equations and bond-slip relationship models of RAC with steel bar has been summarized to ensure engineers to better understand their applicability; The influencing factors of the bond behavior of RAC specimens including the replacement rate of RCA, the concrete compressive strength, the steel bar type and steel bar diameter, the steel bar embedment length and the aggregate performance; The freeze-thaw cycles and the steel bar corrosion all affect the bond behavior of RAC with steel bar. When freeze-thaw damage and steel bars corrosion reach a certain degree, the bond behavior of RAC with steel bar deteriorates.

Ba 2 Zn (1+ x ) Si 2 O (7+ x ) ceramics were prepared using the conventional solid-state method at 1200 °C for 3 h in air. Apart from the previously reported Ba 2 Zn (1+ x ) Si 2 O (7+ x ) ( x = 0) with a monoclinic structure ( C 2/c ), the end-member compositions at x = −1 and 1 exhibit single-phase β -BaSiO 3 with an orthorhombic structure ( P 2 1 2 1 2 1 ) and BaZnSiO 4 with a hexagonal structure ( P 6 3 ), and possess a coexistence of weak ferroelectricity and low-permittivity microwave dielectric properties. A reduction in Zn 2+ content mainly decreases the intensity of the ε r anomaly peak at lower temperature and increases the ε r (or frequency) stability against temperature. The Zn 2+ -rich BaZnSiO 4 phase has a τ f value of −181 ppm/°C, whereas the τ f value of Zn 2+ -free BaSiO 3 phase decreases to −35.4 ppm/°C. The Zn 2+ deficiency in Ba 2 ZnSi 2 O 7 composition could inhibit the presence of BaZnSiO 4 phase and improve the τ f value, whereas excessive Zn 2+ cations prompt the formation of the BaZnSiO 4 phase to deteriorate significantly the τ f value. [ABSTRACT FROM AUTHOR]