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In this work, the effect of Zn content on the formability and aging precipitation of Al–Zn–Mg–Cu–Nb alloys prepared by laser powder bed fusion (LPBF) were investigated via experiments and in-depth characterization. Results show that the increase in Zn content narrows the LPBF processing window, owing to the significant evaporation of Zn element during LPBF. The increase of Zn content not only accelerates the aging kinetics of Al–Zn–Mg–Cu–Nb alloys, but also increases the number density of nanoprecipitates and reduces the PFZ width, resulting in an enhancement in the peak microhardness. The microstructure evolution and aging behavior of alloys during direct aging (DA) and traditional solution treatment and aging (STA) were compared. DA can maintain fine equiaxed grains, while a bimodal grain structure with coarse and fine grains can be obtained after STA. The peak microhardness and the number density of nanoprecipitates in alloys treated with STA is higher than that of alloys treated with DA, which indicates that the traditional STA heat treatment is still applicable to Al–Zn–Mg–Cu–Nb alloys fabricated by LPBF.

Metamaterials, typically consisting of sub-wavelength metal-atom arrays and a dielectric layer matrix such as glass fiber reinforced epoxy resin (FR-4), have been widely used in the field of stealth equipment due to their good electromagnetic parameter designability and strong absorption for electromagnetic waves at specific frequencies. In offensive and defensive confrontations, laser weapons pose a serious threat to the survival of stealth equipment. However, the interaction mechanism between the metamaterials and laser and the effect of laser ablation on microwave absorption performance are still unclear. In this work, we firstly irradiated the double arc-shaped Cu-atom array/FR-4 matrix metamaterials by using a high-energy continuous-wave laser and studied the interaction and response mechanism between them. The high temperature caused by laser irradiation leads to the melting of the metal atoms and the pyrolysis of the resin matrix. By simulating and testing the reflection loss of the metamaterials before and after irradiation, we found that the resin pyrolysis products strongly affect the impedance matching characteristics and reduce the microwave absorption properties significantly in extreme cases. Our findings help deeply understand the interaction between the metamaterials and the laser and will show guidance in the applications involving laser-metamaterial interactions.

In aquatic systems, sediment is both a sink for persistent organic pollutants (POPs) and a potential source of POPs release. Consequently, it is important to understand the pollution characteristics and sources of polychlorinated naphthalenes (PCNs) as POPs of Stockholm Convention in sediment for control of the ecological risk. Atmospheric deposition is a potential source of PCNs in sediment. However, there is no clear report on the contribution of atmospheric deposition to PCNs in sediments. In this study, the Chaobai River in China was selected because it is an important drinking water source that is not affected by wastewater discharge. Surface sediments from the river were analyzed for 75 PCN congeners by using high resolution gas chromatography combined with high resolution mass spectrometry. The total PCNs concentration ranged from 54 to 2266 (mean: 402) pg/g. The toxic equivalent quantity of 19 PCNs in surface sediments was 9.69 × 10−2, and CN73, CN66/CN67, and CN63 had the largest contributions to this value. Dichlorinated and trichlorinated naphthalenes were the dominant homologs. The PCN data from the sediment samples in this study were combined with data for PCNs in ambient air from a literature, which has a good match with this study in both temporal and spatial scales. The contribution of atmospheric deposition to PCNs in the surface sediment was evaluated by comparing congener characteristics and correlation analysis. Our study indicated atmospheric transportation and deposition are important pathways for transport of PCNs into surface sediments.

In this study, a novel protein designated MC-2 was isolated from Momordica charantia L., and the positively regulates lipid metabolism activity was detected by the bile acid binding activity test. Then, the amino acid composition of MC-2 was analyzed, and the total content of Asp, Glu, and Lys is up to 38.96 g/100 g in MC-2. Furtherly, its lipid metabolism activity were explored. In vitro, MC-2 ameliorated FFA-induced HepG2 steatosis phenotypes and intracellular triglycerides level with the promotion of bile acids secretion. In vivo, MC-2 was able to protect rats against NAFLD-induced in response to a high-fat diet through a manner associated with the regulation of inflammatory cytokines and oxidative stress-related factors. The hepatoprotective activity of MC-2 was closely tied to improvements CPT1A, FATP2, ACSL1, and PPAR-α expressions. Together, these data highlight the promise of MC-2 (rich in Asp, Glu, and Lys) as a candidate functional food ingredient.

To characterize the fracture behaviors of the selective laser melting (SLM) processed GTD222 superalloy, in-situ scanning electron microscopy (SEM) observation was conducted during 760 °C tensile deformation. The results showed that the microcracks were mainly nucleated at the grain boundary and then propagating into the grain interior.

Background: Norovirus (NoV) is recognized as a leading global cause of viral acute gastroenteritis (AGE). To better understand the prevalence and genotypic patterns of NoV infection in Southeast China, we conducted a retrospective study of diarrheal syndrome surveillance of NoV and analyzed the epidemiological characteristics of AGE cases and phylogenetic evolution of NoV strains. Methods: 1464 AGE patients in two diarrhea surveillance sentinel hospitals were sampled during 2016 and 2017. NoV Positive samples were genotyped by ORF1/ORF2 overlapping regional gene sequencing. Sequences analyses of the NoV genotypes were confirmed by online NoV Genotyping Tool and the phylogenetic analysis was constructed by MEGA 7.0. Results: 139 (9.49%) of the AGE specimens were NoV positive. The GII strain was the main geno-group in NoV infected patients. At least 12 NoV genotypes and seven recombinant strains were detected. Major NoV genotypic transformations were GII.Pe/GII.4, GII.P17/GII.17 and GII.Pe/GII.17 in 2016 to GII.P16/GII.2, GII.P17/GII.17 and GII.Pe/GII.4 in 2017. Phylogenetic analysis showed that GII.P16/GII.2 recombinant strains clustered with those detected in the USA, Russia and Japan in 2016. Conclusion: We characterized the molecular epidemiology of NoV infection in AGE patients during 2016–2017. The main three NoV GII genotypes circulating in the population of Taizhou were GII.P17/GII.17, GII.Pe/GII.4 and GII.P16/GII.2.The GII.P16/GII.2 genotype has become the predominant strain since first quarter 2017. Monitoring of the NoV genotypic shift is important for the prevention and control of AGE. Keywords: Molecular epidemiology, Norovirus, Acute gastroenteritis, Genotype

Strengthening is a critical issue for improving the mechanical properties of ceramic particles reinforced metal matrix composites (CPRMMCs). A Ni matrix composite reinforced by TiN nano-particles (TiNNP) with a three-dimensional (3D) network structure was synthesized via low-energy ball-milling (LEBM) and spark plasma sintering (SPS). The ultimate tensile strength (UTS) of the TiN/Ni composite is 690 MPa, an increase of 383% compared to that of the Ni matrix. The 3D network structure of TiN nano-particles formed at the grain boundaries refines the grains significantly and generates a high density of dislocations near the TiN/Ni interface, synergistically contributing to the enhanced strength. Ceramic particles of 3D network structure may be a potential solution to achieving superior properties of CPRMMCs.

This article contains data related to the research article entitled “Distribution and potential ecological risk of 50 phenolic compounds in three rivers in Tianjin, China” [1]. This data article reports the detailed information for the contaminant level of phenolic compounds in three rivers in Tianjin, China. The data collects from seven sample sites in Beitang drainage river, sixteen sample sites in Dagu drainage river, and fourteen sample sites in Yongdingxin river. The ranges, standard deviations, average values, median values of the concentrations of identified phenolic compounds in three rivers and the standard deviations, average values, the maximum values of risk quotients of identified phenolic compounds in three rivers are listed in this paper. Keywords: Phenolic compounds, Suspended particulate matter, Surface water, Sediment, Tianjin

Ni base superalloys for structural castings of aero engines demand higher service temperatures and lower costs while retaining their processing characteristics. To achieve these properties, alloying with the rare precious metals inevitably leads to a decrease in the castability and a marked increase in the raw material cost. In this work, we develop a novel Ni base composite (MC/IN718C) with a high creep resistance, excellent microstructure stability and excellent castability by optimizing the chemistry and microstructure of the commercial IN718C superalloy. In this work, both tensile strengths at room temperature and at 704 °C were obviously improved, while the steady-state creep rate of the MC/IN718C composite at 704 °C was reduced by one order of magnitude. The rupture life of MC/IN718C at 704 °C/620 MPa was enhanced by one order of magnitude compared to the IN718C alloy due to the load bearing effect of the MC carbide, the elimination of the metastable strengthening precipitation phase γ″ and a decrease in the harmful Laves and δ phases. MC/IN718C Ni base composite presents a new strategy for the design and preparation of high-temperature materials potentially for critical structural castings. Keywords: Nickel superalloys, Carbides, Synchrotron radiation X-ray diffraction, Creep, Microstructure

The ordered L12 phase generally appears as dispersed precipitates in FCC multi-principal element alloys (MPEAs). In this work, a single L12 ordered intermetallic is obtained in the annealed equimolar FeCoNiV alloy. Experiments show that the FCC to L12 ordering transformation occurs below 778±2 °C, accompanied by lattice contraction, anti-phase boundaries (APBs) formation and low-temperature magnetic moment decrease. A strong linear strain hardening rate up to 5.0 GPa is obtained during the tensile deformation for L12 ordered alloy at room temperature. The ab initio calculations based on the exact muffin‑tin orbitals in combination with coherent potential approximation predict that V atoms prefer to occupy the cubic corner positions of L12 sublattice, and the FCC phase becomes more stable with respect to L12 phase above 849 °C considering the competition between enthalpy and entropy. The ab initio molecular dynamic simulations indicate that V atoms prefer to bond with the unlike atoms (Fe, Co and Ni) in liquid FeCoNiV, which is consistent with the cubic corner site occupation of V in L12 ordered structure. The present work demonstrates a new design strategy of MPEAs which focus on single phase ductile intermetallic compounds. Keywords: High-entropy alloys, Ordering transformation, FeCoNiV, Ab initio calculations, Liquid structure

Only few studies were conducted to assess genotoxicity of centralized source waters in China and almost none of them dealt with the causal relationship between the genotoxic effect and genotoxicants. In this work, 16 centralized source waters in China were sampled from five river systems and genotoxicity of their organic extracts was assessed by use of the SOS/umu test for DNA-damaging effect and the miniaturized flow cytometry-based micronucleus (MN) test for chromosome-damaging effect. In addition, initial identification of potential genotoxicants for the six samples from the Yangtze River was done with a GC/MS method and the QSAR toolbox 3.0. The results demonstrate that eight samples showed both indirect and direct DNA-damaging effects, another four samples showed only indirect DNA-damaging effects, while chromosome-damaging effects were found for 14 out of the 16 samples, in which aneugenic and clastogenic modes of action were found for 4 and 10 samples, respectively. Both direct/indirect DNA-damaging effects and chromosome-damaging effects were induced by the six Yangtze River samples, and the existing different types of genotoxicant confirmed the results. Furthermore, o-phenylphenol was initially identified as the major cause for the DNA-damaging effects while PAHs, pesticides, phenol and anthraquinone were identified as ubiquitous chromosome-damaging agents among these samples. In conclusion, a combination of the SOS/umu test and the miniaturized flow cytometry-based MN test to detect both DNA-damaging and chromosome-damaging effects could be used as a comprehensive genotoxicity assessment tool for the evaluation and classification of genotoxicity of complex mixtures, and potential genotoxicants can be initially identified with additional information from chemical analysis and the QSAR toolbox., (Copyright © 2014. Published by Elsevier B.V.)