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Physisorption of bromopentafluorobenzene (C6F5Br) on graphene can occur due to the unique σ-hole and π-hole characters of C6F5Br and the rich π-electrons region of graphene, leading to the formation of three types of π-hole···π and σ-hole···π interactions. The π-hole···π interactions are even stronger than the σ-hole···π interactions. The property of graphene was significantly affected by such physisorption. [ABSTRACT FROM AUTHOR]

This study investigated the ballistic resistance of a composite target plate fabricated by combining SiC ceramic with the Dyneema fiber. To achieve a light-weight target plate that conforms to the US National Institute of Justice level four (NIJ IV) standards, minimal areal density analysis was conducted to obtain the optimal SiC ceramic-Dyneema fiber thickness combination. This study used energy absorption to analyze the ballistic resistance of the target plates. To drastically reduce experimental costs, most of this work employed ANSYS/LS-DYNA software to conduct finite element numerical simulations. First, ballistic experiments that conformed to NIJ IV standards were conducted to verify the simulation parameter configurations. Subsequently, the correlation function of the relationship between the combined thickness of the composite material and its ballistic resistance was determined through the experimental design, which effectively reduced the simulation analysis time. According to simulation experiments and regression analysis, the equation for the relationship between the combined thickness of the composite material and its ballistic resistance was E A h c , h f = − 6276.5 + 500.6 h c + 1512.6 h f + 30.7 h c h f − 8.1 h c 2 − 113.6 h f 2 , though there were limitations to its application. From the numerical analysis results, 8.1940 mm SiC ceramic and 6.9637 mm Dyneema fiber were determined to constitute the optimal thickness combination for a composite that features a minimal areal density and which conforms to NIJ IV standards. The combination was verified to be consistent with the numerical simulation analysis results. [ABSTRACT FROM AUTHOR]

Cartilaginous endplate (CEP), a thin layer of hyaline cartilage located between the vertebral endplate and nucleus pulposus, transports the nutrient into the disc. The objective of this study was to evaluate the influence of T140 (polyphemusin II-derived peptide) on the CEP cell growth, apoptosis, and the matrix formation via the stromal cell-derived factor-1 (SDF-1)/cysteine X cysteine (CXC) receptor-4 (CXCR4) signaling pathway. Sprague-Dawley rats were euthanized by cervical dislocation and dissected for the isolation and the appraisal of CEP cells that were extracted from the endplate in rat intervertebral discs and were then added with different concentrations of reagents (SDF-1 and T140). The effect of T140 on CEP cell proliferation and apoptosis were analyzed. The messenger RNA (mRNA) and protein expressions of CXCR4, prominin-1, proteoglycans, type II collagen, B-cell lymphoma-2 (Bcl-2), and Bcl-2 associated X protein were analyzed by reverse transcription quantitative polymerase chain reaction and Western blot analysis. T140 promoted the proliferation of CEP cells and inhibited the apoptosis of CEP cells. Additionally, T140 suppressed the mRNA and protein expression of CXCR4, prominin-1, and Bcl-2 associated X protein, and increased the mRNA and protein expression of proteoglycans, type II collagen, and Bcl-2. T140 promotes the proliferation and matrix formation and inhibits the apoptosis of CEP cells by blocking the SDF-1/CXCR4 signaling pathway in vitro, which provides a certain therapeutic effect on the degeneration of intervertebral discs. [ABSTRACT FROM AUTHOR]

Aim: To highlight a potential dynamic interaction between intestinal bacteria (IB) and metabolites that might contribute to liver regeneration (LR). Methods: Male Sprague–Dawley rats were subjected to surgical removal of two‐thirds of the liver and samples were collected over a 14‐day period. Intestinal community and metabolic profiles were characterized to establish their potential interactions during liver regeneration. Results: Partial hepatectomy caused fluctuating changes in the gut microbiome, which paralleled the biological processes of LR. Briefly, the enhanced cell proliferation occurring within 30–48 h was associated with a decreased ratio of Firmicutes to Bacteroidetes reflected by a reduction in Ruminococcaceae and Lachnospiraceae, and an increase in Bacteroidaceae, Rikenellaceae, and Porphyromonadaceae, which was indicative of a lean phenotype. The microbiota derived from rats at 12–24 h and 3–14 days were characterized by elevated F/B ratios, suggesting the differing energy extract behaviors of microbiota during the course of LR. Functional changes of the shifted microbiota revealed by PICRUSt software confirmed the pyrosequencing results. The microbiome derived from hour 12 rats showed overpresentation of metabolism‐related modules. In contrast, the microbiome derived from day 2 rats was functionally unique in "replication and repair", "amino acid metabolism," and "nucleoid metabolism." Upon examining the dynamic pattern of metabolic response, the specific pathways, including glycerophospholipid metabolism, taurine, and hypotaurine metabolism, were identified to be attributable to the systemic alterations in LR‐related metabolism. Moreover, our data indicated that several key functional bacteria were strongly related to perturbations of the above pathways. Conclusion: Gut flora could play a central role in manipulating metabolic responses in LR. [ABSTRACT FROM AUTHOR]

With the hierarchical Green's function approach, we study a doped Mott insulator described with the Hubbard model by analytically solving the equations of motion of an one-particle Green's function and related multiple-point correlation functions, and find that the separation of the spin and charge degrees of freedom of the electrons is an intrinsic character of the doped Mott insulator. For enough of large on-site repulsive Coulomb interaction, we show that the spectral weight of the one-particle Green's function is proportional to the hole doping concentration that is mainly produced by the charge fluctuation of electrons, while the excitation spectrum of the electrons is composed of two parts: One is contributed by the spin fluctuation of the electrons, which is proportional to the hole doping concentration, and another one is coming from the coupling between the charge and spin fluctuations of the electrons that takes the maximum at undoping. All of these low energy/temperature physical properties originate from the strong on-site Coulomb interaction. The present results are consistent with the spectroscopy observations of the cuprate superconductors and the numerical calculations in normal state above the pseudogap regime. [ABSTRACT FROM AUTHOR]

In the present study, the efficacy of unilateral transverse process-pedicle and bilateral puncture techniques in percutaneous kyphoplasty (PKP) for Kummell disease was compared. Between March 2015 and June 2017, 63 patients with Kummell disease were recruited and underwent PKP with two different puncture techniques: A total of 38 patients were treated by unilateral transverse process-pedicle PKP and 25 patients were treated by bilateral PKP. The operative time, intra-operative fluoroscopy time, volume of bone cement injection and bone cement leakage were recorded. Prior to surgery and 1 day post-surgery, the visual analogue scale (VAS) pain score and Oswestry disability index (ODI) were determined, and the vertebral body height and Cobb angle were measured. The results indicated that the incidence of bone cement leakage in the unilateral group was similar with the bilateral group (15.79% vs. 16.00%), with no statistically significant difference between the two groups. None of the patients in the two groups had any obvious damage of the spinal cord. The operative time, intra-operative fluoroscopy time and volume of bone cement injection in the unilateral group were lower than those in the bilateral group. A chest X-ray examination at 1 day post-surgery revealed no pulmonary embolism in the two groups. The VAS score, ODI, vertebral body height and Cobb angle were significantly improved in the unilateral and bilateral groups at 1 day post-surgery and at the last follow-up (12 months post-surgery) as compared with these parameters prior to surgery. In conclusion, the unilateral transverse process-pedicle and bilateral puncture techniques in PKP exhibited good efficacy as a treatment for Kummell disease. The operative time, intra-operative fluoroscopy time and volume of bone cement injection were lower in the unilateral group. [ABSTRACT FROM AUTHOR]

Background: Re-radical surgery is the only curative therapy for unsuspected gallbladder carcinoma (UGC). The aim of this study was to compare prognosis of pT3 UGC patients receiving anatomic hepatectomy (AH) or wedge hepatectomy (WH) combined with en bloc local-regional lymphadenectomy of the hepatoduodenal ligament using propensity score-matching (PSM) analysis. Materials and Methods: A retrospective study was carried out on 81 consecutive pT3 UGC patients who underwent radical re-resection at Eastern Hepatobiliary Surgery Hospital from 2006 to 2015. Overall survival (OS) was estimated using Kaplan-Meier method. The difference in OS between the AH and WH groups was analyzed using the log-rank test and the PSM method. Result: The AH and WH groups showed no significant difference in OS (P > .05) by either log-rank test or PSM analysis. Conclusions: Both AH and WH radical re-resections are effective treatments for UCG patients with pT3 tumors. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to investigate the thermal characteristics of the clutch hydraulic system under various oil flow conditions. Increasing the oil flow is one of the most important approaches to reduce the clutch temperature. However, the effect of the oil flow on the clutch temperature remains to be explored. Design/methodology/approach: The thermal resistance network model and the lumped parameter method are used to study the thermal characteristics of the clutch hydraulic system. The predicted temperature variations of the clutch and the oil are compared with experimental data. Findings: Results demonstrate that the larger the friction power is, the higher the temperatures of the clutch and the oil are. However, the temperature growth rates of the clutch and oil present different trends: the former decreases gradually and the latter increases constantly. Additionally, increasing the oil flow within a certain range gives rise to the decrease of clutch temperature and the increase of oil temperature; nevertheless, their variation trends are gradually weakening. When the oil flow is large enough, it brings a slight effect on the clutch temperature rise. Originality/value: This paper extends the knowledge into the oil flow supply of the clutch hydraulic system. The conclusions can provide a theoretical guidance for the oil management of the transmission system. Additionally, the thermal resistance network model is also effective and efficient for other hydraulic equipment to predict the temperature variation. [ABSTRACT FROM AUTHOR]

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. • The model for circumferential mechanical buckling is presented and validated. • The comprehensive fault diagnosis method of the multi-disc clutch is developed. • The effect of temperature on the friction and wear characteristics of a disc is studied. • The safety mechanical-thermal boundary of the clutch is proposed and validated. • The thickness of separate plate should be varied according to its axial position. [ABSTRACT FROM AUTHOR]

Urban areas in coastal lowlands host a significant part of the world's population. In these areas, cities have often expanded to unfavorable locations that have to be drained or where excess rain water and groundwater need to be pumped away in order to maintain dry feet for its citizens. As a result, groundwater seepage influences surface water quality in many of such urban lowland catchments. This study aims at identifying the flow routes and mixing processes that control surface water quality in the groundwater-influenced urban catchment Polder Geuzenveld, which is part of the city of Amsterdam. Geuzenveld is a highly paved urban area with a subsurface rain water collection system, a groundwater drainage system, and a main surface water system that receive runoff from pavement and roofs, shallow groundwater and direct groundwater seepage, respectively. We conducted a field survey and systematic monitoring to identify the spatial and temporal variations in water quality in runoff, ditch water, drain water, and shallow and deep groundwater. We found that Geuzenveld receives a substantial inflow of deep, O 2 -depleted groundwater, which is enriched in ammonium and phosphorus due to the subsurface mineralization of organic matter under sulfate-reducing conditions. This groundwater is mixed in the ditches during wet periods with O 2 -rich runoff, and iron- and phosphate-rich drain water. Unlike natural catchments, the newly created, separated urban flow routes lead to mixing of water in the main surface water itself, shortcutting much of the soil and shallow subsurface. This leads to low O 2 and high ammonia concentrations in dry periods, which might be mitigated by water level management or artificially increasing O 2 levels by water inlet or artificially aeration of the main water canals. Further research is necessary how to optimize artificial urban systems to deliver a better ecological and chemical status of the surface water. Unlabelled Image • Urbanization of lowlands changes mixing processes between the aqueous compartments. • The impact of groundwater chemistry on surface water is strongest in dry seasons. • Urban mixing changes hydrogeochemical reactions and retention patterns. • Urban runoff brings oxygen and heavy metals to the water system. • Residential deep water levels drive nutrient rich groundwater towards surface water. [ABSTRACT FROM AUTHOR]

In a noisy environment, the interested sound field is interfused with the non-stationary incoming field from the back side of the measurement plane and the scattered field caused by the incoming wave falling on the surface of the target source. In order to remove the non-stationary incoming and scattered fields simultaneously, a recovery method of the non-stationary free field with the pressure and particle acceleration measurements is proposed. First, the mixed time-evolving pressure and particle acceleration are firstly measured on one measurement plane, where the particle acceleration is obtained by the finite difference approximation with the aid of an auxiliary measurement plane; Then, two physical relations are employed to deduce a forward complete recovery formulation of the target source in the noisy environment. One relation contains two impulse response functions relating the time-wavenumber pressure spectrum to particle acceleration and pressure spectra, respectively, and the other is the surface reflection coefficient of the target source relating the scattered field to the incoming field. Finally, the mixed pressure and particle acceleration are substituted into the recovery formulation, and the time-evolving pressure radiated by the target source in free-field is recovered. Thereby, the proposed method possesses a significant feature of real-time recovery of the non-stationary free field. A circular piston fixed on an infinite rigid baffle and two monopole sources are designed in a numerical simulation to test the performance of the proposed method. The simulation results attest that the proposed method not only can recover the time-evolving pressure radiated by the target source in free-field at any space points, but also recover the space distribution of the non-stationary sound field of the target source in free-field at different time instants effectively. An experiment with two speakers embedded in a planar steel plate and a speaker is further employed to verify the validity of the proposed method. [ABSTRACT FROM AUTHOR]

Blueberry is an important health food, as it contains vitamins, anthocyanins, and antioxidative enzymes. However, post-harvest life of this fruit is very short, and its quality (in terms of microbial growth, antioxidant value, and decay rate) deteriorates rapidly during storage. In this work, air cold plasma at atmospheric pressure was evaluated as a pre-treatment approach for prolonging the shelf life and improving the quality of blueberries. After plasma treatment for 10 min, the number of bacteria and fungi decreased by 93.0% and 25.8%, respectively, which might be due to the increases in DNA damage and guanine oxidation. Accordingly, the blueberry decay rates reduced by 17.7%, 14.3%, and 5.2% in the plasma treatment groups of 6, 8, and 10 min, respectively, after 20 days of storage. Interestingly, the contents of sugar, vitamin C, and total anthocyanin as well as the superoxide dismutase activity level showed the maximum increases of 1.5-fold, 1.5-fold, 2.2-fold, and 79.3%, respectively, following different plasma discharge treatments and storage times compared with those in the control groups. Furthermore, in the treated samples, the degradation times for these four parameters to decrease to control levels were longer compared to the samples without treatment. These results indicated that air cold plasma at atmospheric pressure has excellent potential as a method for enhancing the quality and shelf life of fresh produce in the food industry. [ABSTRACT FROM AUTHOR]

Ultra-thin MFI zeolite membranes with different Si/Al ratios (152, 47 and 26) were prepared on graded α-alumina supports in the presence of organic template molecules and evaluated for separation of equimolar CO 2 /CH 4 mixtures at temperatures from 315 to 249 K. The thicknesses of all membranes were less than 500 nm and permporometry showed that the number and size of defects were low for the two membranes with the highest Si/Al ratio (152 and 47). The membrane with the lowest Si/Al ratio (26) also had low amounts of defects in the mesopore range, but did have a few macropore defects. All membranes showed very high CO 2 permeances in the entire temperature range studied and the permeances increased with increasing temperature. The CO 2 permances were also correlated to the Si/Al ratio of the membranes. The higher permeances was observed for membranes with higher Si/Al ratio. The highest observed CO 2 permeance was 142 × 10−7 mol s−1 m−2 Pa−1 at room temperature for the membrane with Si/Al = 152. The separation factor, on the other hand, increased with decreasing temperature for the two membranes with the highest Si/Al ratio (152 and 47), but for the membrane with a Si/Al ratio of 26, the separation factor went through a maximum at ca. 270 K. The highest separation factor observed was 7.1 at 249 K for the membrane with Si/Al = 47. These observations are consistent with an adsorption controlled separation mechanism. Image 1 • MFI membranes with different Si/Al ratios were prepared by using organic template. • The defects distributions for different membranes were evaluated and analysed. • Very high CO 2 premance was obtained for separation of equimolar CO 2 /CH 4 mixture. • The separation factors and CO 2 permances are correlated to the Si/Al ratios. [ABSTRACT FROM AUTHOR]

The secure operation of electricity generation system (EGS) is essential to the quality of electricity and the security of energy Internet. In order to design secure control strategy for EGS, the behavior and capacity of adversary and possible attack should be studied. From this point of view and considering the actuator saturation and the false-data injection attack in control input channel of EGS, we analyze the behavior and stealthiness of adversary and design stealthy attack strategies in this paper. First, we prove that the magnitude of effective attack signal is smaller than the magnitude of injected attack signal because of actuator saturation. Second, we find that smaller actuator saturation limit makes the adversary easier to be detected. Finally, two stealthy attack strategies are designed for EGS which incorporates a $\chi ^{2}$ attack detector, and the effectiveness of them are illustrated through simulation. [ABSTRACT FROM AUTHOR]

In this paper, a new method of multi-objective optimization of the shape parameters was proposed for the Autonomous Underwater Vehicle (AUV) with both towed and self-propelled, aiming to reduce drag and enhance motion stability during navigation. In this study, the hydrodynamics calculation of AUV was conducted by CFD method covering a wide range of Reynolds number between 105 and 107, and the optimization was performed by NSGA-II multi-objective optimization algorithm. Prior to deploying the optimization process, a sample library was created using the Latin hypercube sampling method to construct the Kriging approximation model. Thereafter, the model was used as the NSGA-II multi-objective optimization function, in which the range of design variables was considered to obtain the Pareto optimal solution. Furthermore, we also introduce and discuss the Pareto optimal points with special characteristics. In addition, the objective function values of these four optimal points were compared with the results of the initial model. The results showed that the drag at the four optimal points were reduced by 12.07%, 11.59%, 10.98% and 7.94%, respectively, and the overturning moments were reduced by 1.96%, 7.38%, 12.73% and 14.08%, respectively. The proposed multi-objective optimization method optimizes the shape of AUV effectively and provides valuable guidance for the design of AUV. • A new method of multi-objective optimization of the shape parameters is proposed for AUV. • Latin hypercube sampling and CFD methods are employed to obtain a surrogate model. • The multi-objective optimization is performed using the NSGA-II genetic algorithm. • The Pareto optimal points with special characteristics are presented and discussed. [ABSTRACT FROM AUTHOR]

In this paper, a new method of multi-objective optimization of the shape parameters was proposed for the Autonomous Underwater Vehicle (AUV) with both towed and self-propelled, aiming to reduce drag and enhance motion stability during navigation. In this study, the hydrodynamics calculation of AUV was conducted by CFD method covering a wide range of Reynolds number between 105 and 107, and the optimization was performed by NSGA-II multi-objective optimization algorithm. Prior to deploying the optimization process, a sample library was created using the Latin hypercube sampling method to construct the Kriging approximation model. Thereafter, the model was used as the NSGA-II multi-objective optimization function, in which the range of design variables was considered to obtain the Pareto optimal solution. Furthermore, we also introduce and discuss the Pareto optimal points with special characteristics. In addition, the objective function values of these four optimal points were compared with the results of the initial model. The results showed that the drag at the four optimal points were reduced by 12.07%, 11.59%, 10.98% and 7.94%, respectively, and the overturning moments were reduced by 1.96%, 7.38%, 12.73% and 14.08%, respectively. The proposed multi-objective optimization method optimizes the shape of AUV effectively and provides valuable guidance for the design of AUV. • A new method of multi-objective optimization of the shape parameters is proposed for AUV. • Latin hypercube sampling and CFD methods are employed to obtain a surrogate model. • The multi-objective optimization is performed using the NSGA-II genetic algorithm. • The Pareto optimal points with special characteristics are presented and discussed. [ABSTRACT FROM AUTHOR]

• The IR-PAC based anti-corrosive coating for rebar was prepared. • Compared with OPC and SAC, IR-PAC had good resistance to Cl- penetration, excellent strength against abrasion and impact ductility. • IR-PAC coated rebars has good corrosion resistance. The anti-corrosive coating has been taken as an effective measure to keep rebars from corrosion. In this study, the iron-rich phosphoaluminate cement (IR-PAC) based anti-corrosive coating for rebar was prepared. The Cl- diffusion coefficient, strength against abrasion, and impact ductility of IR-PAC mortar were tested, with ordinary Portland cement (OPC) and sulphoaluminate cement (SAC) mortar as controls. The experimental results demonstrated that the chloride ion diffusion coefficient of IR-PAC was the lowest at any age. Compared with OPC and SAC, the strength against abrasion of IR-PAC at 90 d increased by 19.19 % and 14.32 %, respectively. The impact ductility of IR-PAC at 28 d increased by 28.21 % and 17.37 %, respectively. IR-PAC had good resistance to Cl- penetration, excellent strength against abrasion and impact ductility, which assisted the coating in blocking Cl- intrusion and resisting damage. The optimum SCMs based coating for rebar is as follows: 10.08 % Fly ash (FA), 0.1 % nano-silica (NS), and 0.65 % superplasticizer (SP). The coatings prepared with this formulation were used for electrochemical experiments. The rebars coated with IR- PAC had good corrosion resistance, which proved it is feasible to use IR-PAC to prepare anti-corrosive coatings for rebars. [ABSTRACT FROM AUTHOR]

• CSFV-specific epitopes, the target of neutralizing antibodies, are identified on the D/A domain of E2 protein. • Epitopes 780–794, 810–824, and 846–850 likely form a complex conformational epitope domain. • The residues 783-MGD-785, 789-FGLCPF-794, 813-AFYLVCPIGWTG-824, and 846-REK-848 are critical for antigenicity. • The residue F789 is critical for the antigenic difference between the Riems strain and other CSFV strains. • The identified epitopes are important for developing improved diagnostic tests for CSF. Classical swine fever virus (CSFV) shares high antigenic homology with other members of the genus Pestivirus. Because several pestivirus species can also infect swine, eliciting cross-reactive antibodies, it is important to define CSFV-specific epitopes for the differential diagnosis of classical swine fever (CSF) by serology. For this purpose, epitope mapping of seven monoclonal antibodies (mAbs), recognizing sites on the D/A domain of glycoprotein E2, was performed using recombinant expressed antigenic domains and mutants of E2, as well as an overlapping peptide library. Three CSFV-specific epitopes, i.e. , 780-IEEMGDDFGFGLCPF-794, 810-NGSAFYLVCPIGWTG-824, and 846-REKPF-850, were identified within the D/A domain of E2. Site-directed mutagenesis further confirmed that residues 783-MGD-785, 789-FGLCPF-794, 813-AFYLVCPIGWTG-824, and 846-REK-848 were critical residues in these regions. In addition, a F789S difference within the epitope 780-IEEMGDDFGFGLCPF-794 was responsible for the absence of binding of two mAbs to the E2 protein of the live attenuated CSFV vaccine strain Riems. Structural modeling revealed that, the three epitopes are located near each other, suggesting that they may form a more complex conformational epitope on the D/A domain in vivo. Six of the mAbs neutralized viruses of diverse genotypes, indicating that the target epitopes are involved in virus interaction with cells. The binding of CSFV to cells was significantly reduced after pre-incubation with either truncated E2 proteins comprising the D/A domain or with the CSFV-specific mAbs targeting the domain D/A. These epitopes identified on the D/A domain are important targets for virus neutralization that might be involved in the early steps of CSFV infection. These findings reveal potential candidates for improving the differential diagnosis of pestiviruses by serology. [ABSTRACT FROM AUTHOR]

Microplastics have significant implications for global ecosystems. The microplastic distribution, types, sources, and quantified microplastic-heavy metal synergistic pollution in agricultural soil in Chengdu, China were analyzed. The microplastics were detected in all soil samples collected from 103 sites, with concentrations ranging from 1333 to 15067 particle kg−1. The abundance of microplastics in grassland (12,667 ± 3394 particle kg−1) was more than twice higher than that in open field, vegetable field, orchard, and woodland. The main morphological types of microplastics included fibers, films, and granules (all "3-Dimensional" microplastics), with the colors red, blue, and transparent. Granular and fiber microplastics were predominantly in particles < 500 mm, while film microplastics were uniformly distributed at all sizes. The plastic compositions were mainly polypropylene and polyethylene plastics, accounting for 20.73% and 27.90% of the soil microplastic, respectively. Agricultural plastic applications and irrigation water were the sources of soil microplastics. The concentration of Cd, Cr, and Cu in the microplastics was strongly correlated with the corresponding concentration in the soils (p < 0.01), and the microplastic-heavy metal synergistic pollution might deteriorate the soil environment. The results of soil TOC measurements were influenced by microplastics in the soil. The results provide important data for the characteristics of microplastics in the agroecosystem. [Display omitted] • Microplastics are widespread in agricultural fields in Chengdu, China. • The highest MPs abundance is in grassland among the five cultivation modes. • The main sources of soil MPs are varied among different cultivation modes. • Cd, Cr, and Cu content in soil and in microplastics are positively correlated. • Microplastics may influence the results of soil TOC measurements. [ABSTRACT FROM AUTHOR]

The seismic permanent displacement is an essential aspect to evaluate the seismic stability of slope. The conventional Newmark block method commonly adopts a constant yield acceleration to determine the seismic permanent displacement of slope. In order to reflect a more realistic behavior of seismic displacement, the dynamic kinetic failure mechanism and the instant displacement model of slope reinforced by prestressed anchors in infinitesimal time are established. The time-dependent formula for dynamic yield acceleration is deduced based on upper bound method. A modified method is proposed to determine the seismic permanent displacement within the framework of Newmark block theory. The results are compared with the existing work with regard to the yield acceleration and seismic permanent displacement. Three typical seismic ground motions are performed to study the responses of the anchor force, the dynamic yield acceleration and the seismic permanent displacement. Results show that the anchor force, the dynamic yield acceleration and the seismic displacement all increase continuously during the excitation of seismic ground motion. The anchor causes the yield acceleration to increase, and the seismic permanent displacement to decrease significantly. The conventional method adopting a constant yield acceleration greatly overestimates the seismic permanent displacement. [ABSTRACT FROM AUTHOR]

This paper shows that nanosecond repetitively pulsed discharges were able to mitigate the response of lean methane-air swirl flames to acoustic excitations, at pressures up to 3 bar. Flame transfer functions with and without plasma discharges were investigated at pressures of 1.2, 2.0, and 3.0 bar, in a frequency range 48–380 Hz. Results show that the plasma discharges decreased by up to 50% the gain of the flame transfer functions, regardless of the pressure. Mechanisms responsible for this effect are discussed. [ABSTRACT FROM AUTHOR]

Fan noise has become an important noise component of civil aviation engines with the increasing bypass ratio. The mode identification method is the key to in-duct fan noise testing. The number of modes that can propagate through the duct increases dramatically for high-frequency in-duct fan noise, which requires a large number of microphones to measure the sound field in the duct. Since the number of modes is usually larger than the number of microphones, it is difficult to realize mode identification. A Sparse Bayesian Learning algorithm for mode identification is proposed to solve this problem in this paper. The in-duct sound field is described by a statistical model, and the inverse problem of mode identification is expressed in a Bayesian framework. The non-convex optimization problem of the cost function is considered, iteratively achieving the sparsest solution via a block coordinate descent algorithm in a majorization-minimization framework. The mode identification method based on Sparse Bayesian Learning has high sparsity and can achieve parameter adaptation. The effectiveness of the Sparse Bayesian Learning method for duct mode identification is verified by numerical simulations and experimental tests. The results show that the mode identification method of Sparse Bayesian Learning can accurately identify the target mode using fewer microphones. • Applying the Sparse Bayesian Learning (SBL) method for mode identification, the strong sparse induction performance of the SBL method is better at suppressing the non-target modes and identifying accurate sparse target modes. • The sparsest mode coefficient amplitudes are solved indirectly by estimating the hyperparameters. The optimal parameters can be determined adaptively by iterations without the need for manual selection of parameters. • It is verified through numerical simulations and experimental tests that the mode identification method of SBL can accurately identify target modes with a small number of microphones, and its results have strong sparsity and robustness. [ABSTRACT FROM AUTHOR]

• The models, imaging algorithms, and applications are systematically compared, analyzed, and concluded in this paper to explore the differences between the PAD-DBF and FDD-DBF techniques and provide guidance on the application of the technology. • A large number of simulations are investigated to explore the imaging characteristics of two rotor aerodynamic dipole source imaging technologies under different testing conditions, including different analysis frequencies, axis directions, SNRs, and measured distances. • The two imaging techniques are applied to the semi-anechoic chamber test for rotating dipole sources and the actual BO105 rotor wind tunnel test, respectively, which is further used to compare and validate the imaging effectiveness and applicability of the two techniques. The acoustic imaging technology for rotating dipole sources has been one of the topics concerned. In recent years, two state-of-the-art imaging technologies for rotating dipole sources were proposed, including beamforming technologies based on the predefined axis direction (PAD-DBF) and frequency-domain deconvolution (FDD-DBF). However, a systematic comparison of these two imaging technologies does not currently exist. In this paper, the models and imaging algorithms are firstly systematically compared and analyzed to explore the differences between the two technologies and provide guidance on the application of the technology. Secondly, extensive simulations are investigated to analyze the performance of the two imaging technologies under different working conditions. Finally, the two imaging technologies are applied to the semi-anechoic chamber test for rotating dipole sources and the actual BO105 rotor wind tunnel test, respectively, which is further used to compare and validate the imaging effectiveness and applicability of the two technologies. The analysis shows that both technologies can effectively achieve rotating dipole source localization. The PAD-DBF technology can achieve a more accurate rotating dipole source location, higher imaging resolution at a lower time cost, and it can get more robust imaging results in the low signal-to-noise ratio (SNR) of the wind tunnel environment. In contrast, the FDD-DBF technology can get a more accurate sound source magnitude while effectively imaging the rotating dipole source. [ABSTRACT FROM AUTHOR]

The acoustic vector sensor (AVS) has a wide application in the direction of arrival (DOA) estimation of sound sources including aircraft, underwater or on-land vehicles, search-and-rescue efforts, etc. The performance of only one acoustic vector sensor can compare favorably with a traditional acoustic array in DOA estimation. The anisotropic noise problem of the vector sensor has had a severe affective on the estimation accuracy and has caused little attention until now. In this paper, an AVS measurement system is designed, and an Anisotropic Sparse Bayesian Learning (SBL) method (the A-SBL method) is proposed to model and estimate the anisotropic noise of the AVS system. A high-resolution DOA estimation method is also introduced based on the noise estimation algorithm. The experimental results exhibit the necessity of modeling the anisotropic noise, and the estimation accuracy of the proposed A-SBL method based on the noise model is verified. The comparison of DOA methods shows the superiority of the proposed method, in which the DOA estimation error is not more than 1 °. The proposed method's utility may be found in applications for localization or tracking of targets with prominent acoustic characteristics when the environment is complicated. [ABSTRACT FROM AUTHOR]

Titanium/steel composite plate was prepared by cold-hot rolling method. The influence of temperature on the interfacial reaction behavior of titanium/steel composite plate was studied by double beam focused ion beam system and spherical aberration correction transmission electron microscopy. The results show that the interfacial reaction of the cold-rolled titanium/steel composite plate mainly occurs in the heating stage, and the continuous intermetallic compounds layer formed at the interface during heating fractures during hot rolling. An interfacial layer composed of submicron TiC layer and α-Ti/α-Fe is formed when the hot rolling temperature is not higher than 850 °C, and the interfacial bonding strength increases with the increase of rolling temperature. An interface layer composed of micro (FeTi+TiC)/Fe 2 Ti layer, nano FeTi/Fe 2 Ti layer and micro pores is formed when the hot rolling temperature exceeds 900 °C. The interfacial micro (FeTi+TiC)/Fe 2 Ti layer and micro pores will seriously damage the interfacial bonding quality. • Titanium/steel composite plate was prepared by cold-hot rolling method for the first time. • An interfacial layer composed of submicron TiC layer and α-Ti/α-Fe is formed when the temperature is lower than 850 °C, and the interface is tightly bonded without pore defects. • An interface layer composed of micro (FeTi+TiC)/Fe 2 Ti layer, nano FeTi/Fe 2 Ti layer and micro pores is formed when the temperature is higher than 900 °C. The interfacial micro (FeTi+TiC)/Fe 2 Ti layer and micro pores will seriously damage the interfacial bonding quality. [ABSTRACT FROM AUTHOR]

Botanicals (BOTs) are well known for their anti-inflammatory and antioxidant activities. They have been widely used as feed additives to reduce inflammation and improve intestinal functions in agricultural animals. However, the effects of BOTs on chicken intestinal epithelial functions are not fully understood. The 3D apical-out chicken enteroids recapitulate the intestinal tissue, and allow convenient access to the luminal surface, thus serving as a suitable model for investigating gut functions. The aim of this study was to identify the roles of BOTs in protecting the intestinal epithelium in chicken enteroids under challenging conditions. Apical-out enteroids were isolated from the small intestines of 18 days-old chicken embryos. Lipopolysaccharide (LPS , 10 µg/mL) and menadione (400 µM) challenges were performed in the media with or without BOTs. Paracellular Fluorescein isothiocyanate–dextran 4kD (FD4) permeability, inflammatory cytokine gene expression, and reactive oxygen species (ROS) generation were analyzed post-BOTs and challenges treatments. Statistical analysis was performed using one-way ANOVA and post hoc multiple comparisons among treatments. The results showed that the LPS challenge for 24 h induced a 50% increase in FD4 permeability compared with nontreated control; thymol, thyme essential oil, and phenol-rich extract significantly (P < 0.02) reduced FD4 permeability by 25%, 41%, and 48% respectively, in comparison with LPS treatment. Moreover, the gene expression of inflammatory cytokines was upregulated, tight junction proteins and defensins were downregulated (P < 0.05) after 6 h of LPS treatment, while these BOTs treatments significantly restored the LPS-induced gene expression alterations (P < 0.05). Menadione oxidative challenge for 1 h significantly increased the ROS level compared with unchallenged control. Enteroids treated with thymol and thyme essential oils showed 30% reduced ROS levels, while the phenol-rich extract reduced them by 60%, in comparison with the challenged group (P < 0.0001). These data confirmed the role of BOTs in supporting the barrier function and reducing the disruptive effects of inflammation and oxidation in the chicken intestine. [ABSTRACT FROM AUTHOR]

Antibody-drug conjugates (ADCs) are a class of tumor cell-targeting drugs that have developed rapidly in recent years. From the perspective of further improving ADC targeting and developing natural macromolecules as drug carriers, it is still challenging and necessary to try new targeted drug delivery modalities. In this study, we have developed an antibody-modified prodrug nanoparticle based on biomacromolecule dextran (DEX) to delivery antitumour drug doxorubicin (DOX). Firstly, oxidized dextran (ODEX) and DOX were bonded to yield ODEX-DOX via Schiff base reaction, which can self-assemble into nanoparticles (NPs) carrying some aldehyde groups. Subsequently, the amino groups of CD147 monoclonal antibody were bound to the aldehyde groups on the surface of ODEX-DOX NPs, resulting in acid-responsive and antibody-modified CD147-ODEX-DOX NPs with relatively small particle size and high DOX loading. FT-IR, UV-Vis, HPLC, and 1H NMR were used to demonstrate the successful synthesis of polymer prodrug ODEX-DOX NPs and antibody-modified nanomedicine CD147-ODEX-DOX NPs. Dynamic light scattering (DLS) was used to evaluate the stability and the pH responsiveness of ODEX-DOX NPs in different media and tumour microenvironment. The in vitro total release content of DOX reached approximately 70% in PB 5.0 buffer solution after 103 h. Furthermore, the in vivo antitumour efficacy and biodistribution experiments confirmed that CD147-ODEX-DOX NPs could significantly inhibit the growth of HepG2 tumour. All of the results indicate that this acid-sensitive nanomedicine has higher safety and targeting effects. It promises to be an ideal strategy for future targeted drug delivery systems and anticancer therapies. [Display omitted] • An antibody-modified nanoprodrug based on oxidized dextran (ODEX) and doxorubicin (DOX) was prepared. • CD147 mAb was bound onto the surface of prodrug ODEX-DOX nanoparticles by Schiff base reaction. • The multifunctional nanoparticles have abilities of active targeting and pH responsive drug delivery. • In vitro and in vivo tests prove that antibody-bonded nanoprodrugs have good targeting and tumor-inhibiting effects. [ABSTRACT FROM AUTHOR]

The ventilation work is an important step to be completed before the start of the positive pressure explosion-proof robot. The existing explosion-proof technology uses constant pressure inflation, which will cause explosive gas to accumulate in the corner area of the cavity for a long time. In order to solve this problem, a ventilation method with periodic pulse intake is proposed. Based on the finite element method, the cleaning and ventilation process of the positive pressure explosion-proof robot is simulated and analyzed. The concentration of explosive gas in the robot cavity with time under constant pressure intake and pulse intake with different periods and amplitudes is compared. The simulation results show that the pulse intake is beneficial to the ventilation of the corner position. The period and amplitude of the pulse intake has an effect on the ventilation efficiency, when the period is the same, the greater the amplitude of the pulse intake, the higher the ventilation efficiency; when the amplitude is the same, the smaller the period of the pulse intake, the higher the ventilation efficiency. After experimental verification, the validity of the simulation results is proved. This study helps to improve the ventilation efficiency of positive-pressure explosion-proof robots and provides guidance for practical applications. [ABSTRACT FROM AUTHOR]

Background: Enormous clinical and biomedical researches have demonstrated that microbes are crucial to human health. Identifying associations between microbes and diseases can not only reveal potential disease mechanisms, but also facilitate early diagnosis and promote precision medicine. Due to the data perturbation and unsatisfactory latent representation, there is a significant room for improvement. Results: In this work, we proposed a novel framework, Multi-scale Variational Graph AutoEncoder embedding Wasserstein distance (MVGAEW) to predict disease-related microbes, which had the ability to resist data perturbation and effectively generate latent representations for both microbes and diseases from the perspective of distribution. First, we calculated multiple similarities and integrated them through similarity network confusion. Subsequently, we obtained node latent representations by improved variational graph autoencoder. Ultimately, XGBoost classifier was employed to predict potential disease-related microbes. We also introduced multi-order node embedding reconstruction to enhance the representation capacity. We also performed ablation studies to evaluate the contribution of each section of our model. Moreover, we conducted experiments on common drugs and case studies, including Alzheimer's disease, Crohn's disease, and colorectal neoplasms, to validate the effectiveness of our framework. Conclusions: Significantly, our model exceeded other currently state-of-the-art methods, exhibiting a great improvement on the HMDAD database. [ABSTRACT FROM AUTHOR]

Recovering ammonia from anaerobic digestion (AD) effluent offers the opportunity to produce a renewable fertilizer and reduce environmental impact. A novel process developed for such an application was evaluated during this study. The feature of the process is integrating biogas stripping and gypsum (CaSO 4 ·2H 2 O) absorption. The result revealed that the lower CO 2 content and the absorption temperature contributed the higher efficiency of ammonia recovery. The gypsum solution recovered around 95% of the stripped ammonia when the stripping gas contained 10% CO 2 and it rose to 100% when the gas contained more than 30% CO 2. Furthermore, a statistical model and genetic algorithm were applied to estimate the total ammonia recovery and optimize the operating parameters. The experimental and modeling results indicated that integrating biogas stripping with gypsum absorption can effectively harvest ammonia nitrogen and reduce CO 2 emissions while producing (NH 4) 2 SO 4 fertilizer from AD effluent. [Display omitted] [ABSTRACT FROM AUTHOR]

High compliance with methadone maintenance therapy (MMT) is crucial to successful opioid abstinence in addicts. However, MMT has numerous side effects, including reductions in quality of life and quality of sleep. Many studies have demonstrated that electroacupuncture relieves withdrawal symptoms in opioid addicts. The present study was a case-control study. From January 2015 to September 2016, 106 patients undergoing MMT at a medical center in central Taiwan were recruited and separated into an electroacupuncture treatment group and a control group. Electroacupuncture was performed for 15 minutes twice weekly for 4 weeks. The electroacupuncture treatment group was discovered to have improved quality of life, especially in terms of vitality and mental health. Although electroacupuncture did not significantly improve sleep quality, we found that sleep quality was significantly improved once methadone dosage had been reduced. Electroacupuncture can improve quality of life in patients undergoing MMT. If methadone dosage can be reduced and electroacupuncture can be employed, both sleep and life quality can be improved. [ABSTRACT FROM AUTHOR]

Abstract The effects of dynamical load from acoustic waves to structural responses cannot be neglected for some cases such as a thin structure submerged in a heavy fluid. To deal with this kind of problem, a hybrid numerical method consisting of finite element method (FEM) and boundary element method (BEM) for the acoustic-structural coupling problems is proposed. The FEM is built on the first-order Reissner-Mindlin plate theory and the discrete shear gap (DSG) method is applied to construct a locking-free FEM. A collocation BEM with linear continuous element based on Burton-Miller formulation is adopted with an aim to produce a meshing conforming coupling method with the FEM not only on geometry but also on physical nodal quantities at the interface. In addition, analytical expressions of the singular integrals appeared in the Burton-Miller formulations are available to eliminate the numerical difficulties in the implementation of the BEM. Furthermore, the coupling matrix at the interface based on the conforming linear triangular mesh is obtained analytically to avoid the numerical quadrature. A solution scheme by absorbing the FEM equations to the BEM's is proposed to take the advantage of less memory cost of the linear BEM. Optimized algorithms are designed to reduce the memory cost while keep the accuracy of the coupling method during the absorption of the structure effects to the acoustic domain. Numerical examples are setup to validate the accuracy and demonstrate the potential capability of the proposed method. [ABSTRACT FROM AUTHOR]

• CFD model (VOF-FW-H) was developed for CO 2 -ILs system. • VOF method was improved by adding specific drag force and variable viscosity term. • CO 2 bubble formation in ILs was characterized by acoustic pressure signals. • Flow behavior and mass transfer during CO 2 bubble formation in ILs were studied. Industrial applications of Ionic liquids (ILs) in CO 2 capture are still limited due to lack of research on CO 2 -ILs bubble dynamics. A CFD model was developed to understand CO 2 bubble formation in the pool of ILs by coupling improved VOF (Volume of Fluid) method with FW–H (Ffowcs Williams and Hawkings) acoustic formulation. Conventional VOF method was improved by adding suitable drag force for CO 2 -ILs interaction and ILs viscosity was considered as a variable with dissolved CO 2. The predicted results are in good agreement with experimental measurements. Based on current CFD model, distinct acoustics pressure signals were examined to characterize CO 2 bubble formation stages (growth, necking, detachment). It was investigated that bubble diameter and detachment time were increased with increasing of orifice diameter. Moreover, effects of gas and ILs inlet velocities were explained by fluctuations in Reynolds number and acoustic pressure signals respectively. Higher dissolved CO 2 quantity and earlier bubble detachment time were obtained in aqueous ILs than pure ILs. The results have potential to give some useful guidelines to design industrial gas distributor (multiple-holes) for CO 2 -ILs system. [ABSTRACT FROM AUTHOR]

Chemical composition difference widely exists in real fuels, and the composition difference will affect the fuel autoignition and heat release in HCCI-based advanced engines. This study aims to explore the composition effects on autoignition by comparing the autoignition characteristics of two commercial diesels (China Stage-V and Stage-VI). The main composition difference is that Stage-V diesel has a higher paraffin content and a lower naphthene content than Stage-VI diesel. Ignition delay times (IDTs) of the two diesels were measured in a heated rapid compression machine at equivalence ratios of 0.37–1.25, pressures of 10–20 bar, and temperatures of 687–865 K. It is found that the difference in the total IDTs of the two diesels varies with the temperature range, and the first-stage IDTs of Stage-V diesel are much shorter than those of Stage-VI diesel. The IDT discrepancies were appropriately explained using the composition difference between the two diesels. Model simulation was carried out using a ternary and a five-component diesel surrogate coupled with an updated kinetic model. Simulation results show that the composition effects on the autoignition of the two diesels can be well captured by the two surrogates, where the ternary and five-component surrogates agree well with Stage-V and Stage-VI diesels, respectively. To further reveal the intrinsic mechanism of the composition effects, low-temperature reactivity difference between the two surrogates was interpreted from a kinetic perspective. Rate of production (ROP) analysis on OH radical confirms that the addition of decalin in the five-component surrogate is primarily responsible for the longer first-stage IDT compared to the ternary surrogate. Since the two surrogates capture the composition difference and autoignition characteristics of the two diesels, the conclusion from the kinetic analysis will help understand the composition effects on the autoignition of the diesels. [ABSTRACT FROM AUTHOR]

Abstract Autoignition characteristics of RP-3 kerosene were investigated using a heated rapid compression machine and a heated shock tube over a wide range of conditions. Ignition delay times (IDTs) for RP-3 kerosene were measured at pressures of 10, 15 and 20 bar over a range of temperatures from 624 to 1437 K and for equivalence ratios from 0.5 to 1.5. A three-component surrogate fuel (49.8% dodecane, 21.6% iso-cetane and 28.6% toluene by mole) was proposed and a kinetic model was developed to describe the combustion chemistry of RP-3. Negative temperature coefficient (NTC) behavior was observed in the autoignition, of which the temperature range varied within 701−884 K depending on operating conditions. IDT correlations in low and high temperature regions were obtained and then the dependences of IDT on pressure, equivalence ratio, oxygen content and dilution ratio were systemically studied. Comparison between the predictions using the new model and the experimental data shows that this model can accurately describe the autoignition characteristics of RP-3. Brute force sensitivity analyses were carried out to identify the key reactions that govern the ignition event. The large experimental data set and kinetic model provided in the current work will provide insights into the understanding of RP-3 ignition. [ABSTRACT FROM AUTHOR]

Abstract The crucian carp (Carassius auratus) and common carp (Cyprinus carpio) are close relatives and coexist in most of their natural habitats but with different levels of abundance. The crucian carp is usually more abundant than the common carp in high predation-pressure habitats. To verify whether the crucian carp exhibits a significantly higher survival capacity combined with additional antipredator strategies than the common carp, we measured the morphology, behavioral traits, fast-start escape swimming performance and survival time under predation in both fish species. Additionally, the relationships between morphology, behavioral traits, locomotion and survival in both fish species were analyzed to determine which components can explain survival. We found that the crucian carp showed significantly higher survival times combined with greater body depth and fast-start escape performance than did the common carp, and the fast-start escape performance may be the main reason that the crucian carp showed a higher survival capacity. Additionally, the predator (Channa argus) chased the common carp more frequently when exposed to both species simultaneously. The higher survival capacity of the crucian carp and the preference of the predator for the common carp may be partial reasons that crucian carp were more abundant in habitats with high-predation pressure. Despite the differences among species, only the fast-start maximum velocity and exploration of the crucian carp were significantly related to survival time based on Pearson correlations. Overall, the relationships between the components measured in this study and survival in both fish species were quite weak or even lacking, which may be associated with the lack of predation experience in the fish specimens used. Highlights • We examined why the proportions of two closely related fish species are different abundant in high-predation habitats. • The more abundant fish have larger body depth, stronger fast-start escape performance and greater survival than the less abundant fish. [ABSTRACT FROM AUTHOR]

Abstract This paper presents an analytical solution for calculation of flux density distribution on the image plane of a round spherical heliostat which is deduced from the convolution-based integration method. The two-dimensional integration for flux density calculation is converted to a one-dimensional integration and solved as a function, thereby reducing the amount of calculation and obtaining fast computation. The flux density on the receiver plane can be calculated through projection even if the distance between the heliostat and receiver is not equal to the focal length of the heliostat. The ray tracing and numerical method are applied to validate the accuracy of the analytical method which shows the analytical method can be applied to most heliostats for solar tower system with a faster calculation speed than SolTrace code, and the error source is analyzed, which is inversely proportional to the cube of the focal length f and is proportional to the biquadrate of the heliostat radius R 0. It is proved that a radially symmetric solar flux density distribution on the image plane is produced by a round spherical heliostat, which is so far the only radially symmetric solar flux density distribution formed by the heliostat when the incident angle is not 0. Highlights • Analytical solution for solar flux by heliostats with Walzel model. • Numerical method for solar flux by a round focusing heliostat. • A radial distribution of the solar flux at the image plane of round heliostat. • The error of the convolution based method is related to the ratio of the focal length to the size of heliostat. • Analytical solution for solar flux by heliostats with pillbox model. [ABSTRACT FROM AUTHOR]

Abstract By introducing the phase transformation of electron operators, we map the equation of motion of an one-particle Green's function into that of a non-interacting one-particle Green's function where the electrons are moving in a time-depending scalar potential and pure gauge fields for a D-dimensional electron gas, and we demonstrate that the electronic correlation strength strongly depends upon the excitation energy spectrum and collective excitation modes of electrons. It naturally explains that the electronic correlation strength is strong in the one dimension, while it is weak in the three dimensions. [ABSTRACT FROM AUTHOR]

In order to explore the genetic evolution of Actinobacillus pleuropneumoniae (App) in different countries and clarify the relationships among different App in each region, the 16S rRNA gene of App in the NCBI nucleotide database was analyzed and compared by the bioinformatics method. The phylogenetic tree was constructed after tailoring alignment. The results showed that a stable genetic phenomenon was indicated in the evolutionary process of App. The isolates derived from China were clustered and showed a high degree of conservation. They had a certain genetic relationship with the British and American strains, but had far rela tionship with the strains from Japan which was a neighboring country of China. The isolates from different countries in the Eurasian continent shared high homology. The isolates of the two regions originated from common ancestors. [ABSTRACT FROM AUTHOR]

Abstract Autoignition and oxidation characteristics of a three-component diesel surrogate fuel were studied in a heated rapid compression machine (RCM) and a flow reactor (FR) over a wide range of conditions. The surrogate components, n-cetane, 2,2,4,4,6,8,8-heptamethylnonane (HMN), and 1-methylnaphthalene (1-MN), all fall within the C10–C20 range of real diesel fuel. The RCM-measured ignition delay times (IDTs) and FR oxidation data of the surrogate fuel were then compared with those of the target diesel. It is found that the diesel surrogate fuel is in good agreement with the target diesel in total ignition delay time and FR speciation data over the whole temperature range, reflecting the success of the surrogate fuel construction. A semi-detailed kinetic model was used to predict the autoignition and oxidation behavior of the surrogate fuel in RCM and FR experiments. Results show that the kinetic model captures well the measured total IDTs and the mole fractions of O 2 , H 2 , CO 2 , and small hydrocarbons under all investigated conditions. To deepen the understanding of low-temperature reaction scheme, rate of production (ROP) analysis of OH and HO 2 radicals was carried out during the first-stage ignition to explore the causes of low-temperature and negative temperature coefficient (NTC) reactivity. A brute force sensitivity analysis of first-stage ignition delay time was also conducted to further identify the controlling reactions in the first-stage ignition of the surrogate fuel. [ABSTRACT FROM AUTHOR]

Abstract In a cable-stayed bridge, the employment of magnetorheological (MR) dampers among stay cables are steadily increasing for mitigation of rain-wind induced vibration. A major problem for the practical application of these devices is to develop a suitable algorithm that effectively suppresses the vibration of stay cables with basic calculations and minimal feedback requirement. This paper discusses an optimal equivalent control algorithm for vibration mitigation of stay cables based on the linear quadratic regulator (LQR). The control algorithm is anticipated to effectively reduce the risk of structural response amplification, which is due to the control forces along the direction of MR damper motion. Furthermore, this algorithm approximates the optimal LQR control forces through equivalent stiffness and damping, resulting in a significant reduction in the calculative effort of the optimal control forces. Hence, it is proved as a great significance for the MR semi-active control system application in the field of practical engineering. In the proposed equivalent control technique, control performance is evaluated by the vibration control problem faced by wind induced stay cable of the Second Nanjing Yangtze River Bridge. The results demonstrate that the MR semi-active control algorithm as proposed in this paper performs better than that of optimal passive control with almost achieving the level of LQR control with minimal feedbacks requirements. [ABSTRACT FROM AUTHOR]

The lead-free perovskites derivatives of Cs3Sb2X9 (X = Cl, Br, I) have been synthesized, but their photocatalytic properties are not explored. To evaluate the feasibility for the visible light catalytic performance, we calculate the structural, electronic, optical and charge transfer properties of Cs3Sb2X9, based on the hybrid density functional theory of HSE06 with the projector augmented wave potential. The results show the decrease of band energy gaps and the redshift of absorption edges from X = Cl to I. The absolute potential of the valence band maximum and conduction band minimum is determined to justify the feasibility of the photocatalytic water splitting or CO2 reduction. The calculated carrier mobilities reveal that the high electron mobilities of Cs3Sb2I9 are beneficial to the reducing powers for hydrogen generation and CO2 reduction. The present results indicate that Cs3Sb2I9 is appropriate for the photocatalytic water splitting to produce hydrogen or the CO2 reduction driven by the visible light. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a novel time-domain equalizer for visible light communication (VLC) system using machine learning (ML) method. In this work, we employ discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) as modem scheme and convolution neural network (CNN) as kernel processing unit of equalizer. After estimating channel state information (CSI) from training sequence, the proposed equalizer recovers transmitted symbols according to the estimated CSI. Numerical simulations indicate that the equalizer can significantly enhance bit error rate (BER) performance. For example, when signal-to-noise ratio (SNR) is 20 dB and 16/32/64-quadrature amplitude modulation (QAM) is exploited, original BER is about 0.5 while the BER after recovery achieves 1 0 − 5 , which is much lower than forward error correction (FEC) limit 3. 8 × 1 0 − 3. This work promotes the application of ML in VLC domain. To the best of our knowledge, this is the first time a CNN-based equalizer has been explored. [ABSTRACT FROM AUTHOR]

Uniform spherical Ag NPs with controllable size are synthesized in a simple one-step aqueous solution system. A unique digestive ripening process is observed using in situ UV-vis spectra, which performs key functions for the formation of ultra-uniform Ag NPs. [ABSTRACT FROM AUTHOR]

Abstract The reconstruction of sound sources is recognized as a typical inverse problem consisting of back-propagating the measurements of an array onto the sources plane based on the propagation function of the sound. In this paper, the reconstruction of the cyclostationary sources in noisy environment is investigated. The cyclostationary sources assumption covers a wide range of sound sources with a cyclic transfer of energy in time, which are usually generated from the repetitive physical mechanism of a rotating machine. The rotating machines are commonly assembled with the mechanical components generating the stationary sources. The proposed back-propagating cyclic wiener filter aims at reconstructing only the cyclostationary sources from the total measurements of with stationary noises. The proposed method can be considered as an extension of the classic cyclic wiener filter, where the latter can only filter the mixed signals in the time domain whereas the former can reconstruct the spatial sources by integrating the propagation function. Thus, it extended the classic cyclic Wiener filter from the filtration of measurements to the reconstruction of sources by a cascade of the cyclic wiener filter and the Bayesian focusing. The proposed method is first validated by a laboratory experiment in a semi-anechoic chamber. Next, an industrial application involving engine bay on-site measurements is investigated to validate the proposed method: a cyclostationary source on the High Pressure Pump (HPP) is reconstructed, free of the noise interference from the engine. Highlights • The reconstruction of cyclostationary sources with noisy measurements is investigated. • The back-propagating cyclic wiener filter is proposed. • Laboratory experiment and industrial example are given to demonstrate the proposed method. [ABSTRACT FROM AUTHOR]

Abstract 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. Highlights • A coupled numerical multi-physics model is presented to study the generation and variation mechanisms of friction torque. • The bench test is conducted to verify the accuracy of numerical model and investigate the stability of the friction torque. • The most significant operating factor affecting the friction stability is the applied pressure, followed by the rotating speed and ATF temperature. [ABSTRACT FROM AUTHOR]

The electrode configuration determines the thermophysical field during the electroslag remelting (ESR) process and affects the final microstructure of the ingot. In this work, ingot with a diameter of 400 mm was prepared with two electrode configuration modes of single power ESR process, namely one electrode (OE) and two series-connected electrodes (TSCE). Finite element simulation was employed to calculate the electromagnetic field, flow field and temperature field of the ESR system. The results show that the temperature of the slag pool and the metal pool of the TSCE process is lower and more uniform than that of the OE process. The calculated temperature distribution of the ingot could be indirectly verified from the shape of the metal pool by the experiment. The experimental results show that the depth of the metal pool in the OE ingot is about 160 mm, while the depth of the TSCE ingot is nearly 40 mm shallower than that of the OE ingot. Microstructural comparisons indicate that coarse eutectic carbides are formed in the center of the OE ingot, whereas more even eutectic carbides appear in the center of the TSCE ingot. In general, compared with the OE process, the TSCE process is preferred to remelt high speed steel ingots. [ABSTRACT FROM AUTHOR]

Development of a neutral Zn–air battery is of much significance due to the high stability of zinc in a neutral electrolyte. Here, Ni/Co-doped C–N nanotube composites (C–N, Ni/C–N, Co/C–N, and Ni–Co/C–N) as efficient oxygen reduction reaction (ORR) electrocatalysts in a neutral medium have been prepared by direct pyrolysis of Ni/Co salt, dicyandiamide (DCD) and glucose. Among the synthesized catalysts, Ni–Co/C–N presents a high ORR current density of 8.5 mA ⋅ cm − 2 in a 0.5 mol ⋅ L − 1 KNO3 solution. The ORR electron transfer number of the catalyst Ni–Co/C–N is 3.8, indicating that O2 is almost completely reduced to H2O. A neutral zinc–air battery utilizing a 0.5 mol ⋅ L − 1 KNO3 solution has been assembled by using the prepared composite catalyst coated on carbon paper as an air cathode, and Zn plate as an anode. The battery with the cathode catalyst Ni–Co/C–N delivers the open-circuit voltage of 1.13 V and the maximum power density of 65 mW ⋅ cm − 2 . The constant discharge current density of 50 mA ⋅ cm − 2 , 100 mA ⋅ cm − 2 and 150 mA ⋅ cm − 2 can last 202 h, 93 h and 11 h, respectively. A stable voltage plateau appears at various discharge current densities. The neutral zinc–air battery can be repeatedly discharged after replacing the zinc anode. Results indicate that the synthesized Ni–Co/C–N catalyst is an excellent cathode material applied to a neutral zinc–air battery, showing broad application prospects as a mobile power source. Ni/Co-doped C–N nanotube composites have been prepared through direct pyrolysis of Ni/Co salt, dicyandiamide and glucose. The Ni–Co/C–N catalyst presents a more uniform size of nanotube particles with diameter as small as 30 nm, and it possesses excellent ORR performance as the cathode catalysts of neutral Zn–air battery. [ABSTRACT FROM AUTHOR]

Abstract Diesel/gasoline blended fuel, also named as dieseline, has attracted worldwide interests in varied advanced engine combustion modes dominated by mixing time scale and chemical reaction time scale. However, the research on ignition properties and chemical reaction mechanism of diesel/gasoline blends over wide operating conditions is still lacking. In current study, ignition delay time measurement of diesel/gasoline blends with different diesel proportion (30%, 50%, and 70% by volume) were conducted in a heated shock tube and a heated rapid compression machine (RCM) covering a broad range of temperatures between 636 and 1317 K at pressures between 6 and 20 bar for gas-phase dieseline/O 2 /N 2 mixture at varying equivalence ratios from 0.5 to 1.5. The experimental results revealed different dependence of ignition delay time on pressure, equivalence ratio and composition at different temperatures and varying negative-coefficient (NTC) behaviors were also observed at intermediate-temperature regime. The increase in proportion of diesel led to shorter ignition delay times under all conditions, though the ignition data at high temperature only showed marginal discrepancies. Besides, a crossover of ignition data occurred at the highest temperature for varying equivalence ratios. A tertiary surrogate for diesel and a tertiary surrogate for gasoline were chosen to calculate conditions after reflected shock in shock tube and compression in RCM. Then, simulations of ignition delay time for diesel/gasoline blends were conducted using a detailed model. Finally, kinetic analyses were performed to gain insight into the ignition characteristic of diesel/gasoline blends. [ABSTRACT FROM AUTHOR]

Highlights • Large scale PS MCC film was obtained by combining spin-coating and lifting up method. • SDS solution was used to reduce the PS particle space. • The lifting-up process repaired the defects of PS films. • Hybrid film microlens array was obtained using the PS film as a mask. Abstract PS microspheres emulsions with different PS diameters of 207 and 378 nm were prepared by using an emulsifier-free polymerization method. A novel secondary self-assembly method which combined the spin coating and the lifting-up method was used to prepare the close-packed PS MCC films. During the process, the PS MCC film was firstly assembled on a glass substrate by a spin coating technique. Secondly, the obtained PS MCC film was transferred on the air-water interface by immersing the PS glass substrate in water using a dip-coater. Thirdly, the floating close-packed PS MCC films on the air-water interface was transferred to a new glass substrate by using a lifting-up method. During the spin-coating and the self-assembly process, some SDS solution was added in the PS films to improve the uniformity of the PS layer. Effects of the spin-coating speeds, the SDS solution concentration and the lifting-up rates on the morphology of PS MCC films have been discussed. Scanning electron microscopy was used to observe the morphological properties of the PS colloidal crystal films. Results indicate that a relatively close-packed and large scale PS MCC films can be obtained when the spinning speed is 2000 rpm for 60 s, the SDS solution concentration is 2 wt% and the lifting-up rate is 2 mm/min. Furthermore, the polydimethylsiloxane soft mold was replicated from the-fabricated PS MCC films and was then imprinted onto the photosensitive hybrid film under UV-irradiation and thus the micro-lens arrays built in the photosensitive hybrid sol–gel film were obtained. [ABSTRACT FROM AUTHOR]