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Avian pathogenic Escherichia coli (APEC) is primarily responsible for causing septicemia, pneumonitis, peritonitis, swollen head syndrome, and salpingitis in poultry, leading to significant losses in the poultry sector, particularly within the broiler industry. The removal of the lpxL and lpxM genes led to an eightfold decrease in the endotoxin levels of wild APEC strains. In this study, mutant strains of lpxL / lpxM and their O1, O2, and O78 wild-type strains were developed for an inactivated vaccine (referred to as the mutant vaccine and the wild-type vaccine, respectively), and the safety and effectiveness of these two prototype vaccines were assessed in white Leghorn chickens. Findings indicated that chickens immunized with the mutant vaccine showed a return of appetite sooner post-immunization and experienced earlier disappearance of nodules at the injection site compared to those immunized with the wild-type vaccine. Pathological examinations revealed that lesions were still present in the liver, lung, and injection site in chickens vaccinated with the wild-type vaccine 14 days post-vaccination (dpv), whereas no lesions were found in chickens vaccinated with the mutant vaccine at 14 dpv. There were no significant differences in antibody levels on the challenge day or in mortality or lesion scores between challenged birds immunized with either the mutant vaccine or the wild-type vaccine at the same dose. In this study, the safety of a single dose or overdose of the mutant vaccine and its efficacy at one dose were evaluated in broilers, and the results showed that the mutant vaccine had no adverse effects on or protected vaccinated broilers from challenge with the APEC O1, O2, or O78 strains. These results demonstrated that the mutant polyvalent inactivated vaccine is a competitive candidate against APEC O1, O2, and O78 infection compared to the wild-type vaccine. [ABSTRACT FROM AUTHOR]

Strain-induced phase transformation in a dual-phase Mg–Li alloy after a severe deformation has been investigated. β-Li phase was transformed into α-Mg phase as a consequence of large strain cold rolling. The morphology and density of the strain-induced phase could be controlled by slip activation in the β-Li phase. A multi-direction rolling procedure was designed to enhance phase transformation behavior. High density strain-induced phase refined phase structure and greatly promoted the yield strength of the material without a sacrificing the ductility. Strain-induced phase transformation is a potential method for improving the mechanical properties in dual-phase alloys. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Abstract The microstructure and texture characteristics of commercial pure Ti after friction stir processing (FSP) with a slow rotation speed were studied. The shoulder friction zone (SFZ) which did not exist in the FSPed pure Ti with normal rotation speed (> 250 rpm) was observed in the sample treated with a slow rotation speed of 180 rpm. The texture of SFZ in the pure Ti was affected by shear stress from the shoulder of stir tool and the c-axes of the grains in this zone were nearly parallel to the processing direction. While crystallographic texture in the normal stir zone (SZ) were nearly perpendicular to the processing direction. The maximum depth of SFZ in the sample with 180 rpm was 1.2 mm, which decreased with the increased rotation speed until it disappeared. The grains in the SZ of specimen following FSP at a slow rotation speed were fine and homogeneous. The microhardness increased from 150.2 HV to 191.6 HV after FSP at 180 rpm. The microhardness trends were related to grain sizes, work hardening and texture evolution. The slow rotation speed processed alloy boosted the yield strength by 71.7% after the FSP. Highlights • Shoulder friction zone of pure Ti formed during FSP with a slow rotation speed. • Texture was not uniform in the thickness direction of FSPed pure Ti processed with a slow rotation speed. • Grain size decreased and microstructure homogeneity in thickness increased in pure Ti by FSP with a slow rotation speed. • Mechanical properties of pure Ti were developed after FSP with a slow rotation speed. [ABSTRACT FROM AUTHOR]

The microstructure and mechanical properties of AZ80 wrought magnesium alloys with varying Sn contents (0, 1, 2 and 4 wt.%) have been studied by thermodynamic and precipitation kinetics calculation and examined using scanning electron microscopy (SEM), transmission electron microscopy (TEM), hardness test and uniaxial tensile test at room temperature in this paper. The results of thermodynamic and precipitation kinetics calculation showed that the precipitation sequences were determined by the content of Sn element. It was found that in the aging treatment of this work, Mg 17 Al 12 phase precipitated sooner than Mg 2 Sn phase in the alloys with less than 1.72 wt.% Sn and there was a contrary precipitation sequence of these two phases in the alloys with more than 1.72 wt.% Sn. Experimental results were in agreement with those of calculation. According to SEM and TEM observation, Sn promoted precipitation of Mg 17 Al 12 on aging temperature, however the preferential Mg 2 Sn phase suppressed discontinuous Mg 17 Al 12 precipitates by hindering the growth of these in their growth direction. AZ80 with 1–2 wt.% Sn as-aged alloys exhibited outstanding mechanical property that UTS, YS and EL were ∼420 MPa, ∼290 MPa and ∼5%, respectively. [ABSTRACT FROM AUTHOR]

Friction stir processing (FSP) was successfully performed on ultra-light dual-phase LZ91 Mg Li alloy, which provided a chance to study the microstructure and texture evolution of this alloy during severe plastic deformation. The results showed that LZ91 Mg Li alloy could be processed successfully with 200–400 rpm, 25 mm/min, and water cooling during FSP. No defects were observed on the surface and in the cross-section. The microstructure was strongly influenced by the material flow modes during FSP. Two greatly phase refinement regions were found in the stir zone where the α-Mg and β-Li phases were refined to submicron scale and homogeneously mixed. Maelstrom currents flow between two threads on the pin triggered this phase fragment. The high rotation rate of FSP leads to a remarkable recrystallization and grain growth due to the high heat input. The severe plastic deformation caused a phase transformation inside the refined α-Mg phase. The new phases enriched Li element exhibited a coherent relationship with the matrix. It shows that FSP promoted the short-term diffusion in refined α-Mg. • Two phases in dual-phase Mg Li alloy were refined to submicron scale and distributed evenly after FSP. • Materials flow modes strongly influenced the grain refinement and phase distribution in FSPed Mg Li alloy. • A phase transformation inside refined α-Mg phase was discovered and analyzed. [ABSTRACT FROM AUTHOR]

The dried and pulverized medical solid waste was pyrolyzed at 500 °C, and the components and characteristics were analyzed after the solid, liquid and gas products were collected respectively. Experimental results showed that the combustible component in the obtained gas product accounted for 83.22% and the heat value was 10,995.02kcal/Nm3. The liquid product obtained was black viscous tar with a heat value of 8972.82 kcal/kg, GC/MS analysis indicated that hydrocarbons and lipids accounted for about 60% of liquid product, and the carbon chain length of the products is C 6 –C 28. The carbon content of solid product after purification was up to 63.13%, and the heat value was 5454.54 kcal/kg. Furthermore, in order to make the most of the pyrolysis oil, the liquid product was separated and purified by fractional condensation under the condition of decompression. The effect of process parameters such as vacuum degree and condensing temperature was emphasized, and the optimum technological condition was obtained as follows: vacuum degree 0.04 MPa, heating temperature 140 °C and the first stage condensing temperature was 70 °C. Finally, the viscosity measurement of the residual high-viscosity components was intended to provide data support for the solution of tar plugging equipment and piping problems in practical applications. • Mixed medical waste was selected as pyrolysis raw materials. • The heat value of gas and solid products were 10,995.02kcal/Nm3 and 5454.54 kcal/kg. • The oil was reprocessed by fractional condensation to obtain the optimum condition. • This study provides a reference for the high-value utilization of medical waste. [ABSTRACT FROM AUTHOR]

Polyamidoamine (PAMAM) dendrimers grafted Polyacrylonitrile (PAN) UF membrane (PAN-PAMAM) was prepared for the first time. The optimized PAN-PAMAM membrane showed both a high flux (420 L m−2 h−1.bar−1) and a good BSA rejection (99%). To improve its hydrophilicity, the membrane was further modified with ethanolamine (ETA) under different conditions. The results suggest that PAN-PAMAM membrane modified by ETA/NaOH has an improved antifouling property for sodium alginate (SA), humic acid (HA) and bovine serum albumin (BSA), the flux recover ratio (FRR) increased from 61% to above 91%. Moreover, the modified membrane shows a better antifouling property in phosphate-buffered saline (PBS) solution than in water solution. DLS results showed that BSA aggregate morphology are different in two solutions. AFM image and BSA adsorption revealed that PBS decreases the coverage and amount of BSA adsorbed on the membrane surface, leading to an improved antifouling property. Surface tension and XDLVO theory were further used to analyze the fouling process. It was found that ETA/NaOH modification greatly increases the Lewis acid-base interfacial interaction of membrane. However, after the adsorption of BSA, Lewis acid-base interaction decreases greatly, leading to the irreversible fouling of membrane. Image 1 • PAMAM grafted PAN UF membrane with good performance was prepared for the first time. • ETA/NaOH modification further reduced BSA adsorption and improved antifouling property. • PBS solution reduced the coverage and amount of adsorbed BSA on membrane surface. • XDLVO theory analysis shows the adsorbed BSA reduces the Lewis AB interfacial interaction. [ABSTRACT FROM AUTHOR]

Highly efficient visible-light-driven heterojunction photocatalysts, spindle-shaped nanoporous TiO 2 coupled with graphitic g-C 3 N 4 nanosheets have been synthesized by a facile one-step solvothermal method. The as-prepared photocatalysts were characterized by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N 2 adsorption-desorption analysis and UV–vis diffuse reflectance spectrometry (DRS), proving a successful modification of TiO 2 with g-C 3 N 4 . The results showed spindle-shaped nanoporous TiO 2 microspheres with a uniform diameter of about 200 nm dispersed uniformly on the surface of graphitic g-C 3 N 4 nanosheets. The g-C 3 N 4 /TiO 2 hybrid materials exhibited higher photocatalytic activity than either pure g-C 3 N 4 or nanoporous TiO 2 towards degradation of typical rhodamine B (RhB), methyl blue (MB) and methyl orange (MO) dyes under visible light (>420 nm), which can be largely ascribed to the increased light absorption, larger BET surface area and higher efficient separation of photogenerated electron–hole pairs due to the formation of heterostructure. In addition, the possible transferred and separated behavior of electron–hole pairs and photocatalytic mechanisms on basis of the experimental results are also proposed in detail. [ABSTRACT FROM AUTHOR]

Peanut shells were used as raw materials, and the synergistic effects of various acid pretreatments and catalytic pyrolysis for biomass were comprehensively studied. The results showed that the oil yield of 0.5 mol/L hydrochloric acid treatment was 44.75 wt%, and that of 0.5 mol/L acetic acid treatment was 43.40 wt%. The solid products decreased apparently after pretreatment. Acid-washing pretreatment and the subsequent catalytic pyrolysis of the pretreated biomass promoted the yield of aromatic in bio-oil. The yield of bio-oil gradually decreased while the gas yield increased with the increase of catalytic pyrolysis temperature. Ketones and anhydrosugars were also reduced in the bio-oil, while aromatics increased significantly, reaching the highest value of 19.62 wt% (0.5 mol/L hydrochloric acid treatment) and 19.30 wt% (0.5 mol/L acetic acid treatment) respectively at 600 ℃. Synergy effect facilitated the conversion of pyrolytic intermediates to gas and aromatics. Besides, the possible formation mechanism of bio-oil under different pyrolysis conditions is proposed. The study indicates the optimized combination could effectively improve the quality of bio-oil. [Display omitted] • Pretreatment reduce acids and ketones and contribute to the generation of sugars (27.25 wt%). • Acid-washing and catalyst synergistically promote the yield of aromatic in bio-oil. • Anhydrosugars from pretreatment are important raw materials for aromatization. • Bio-oil yields (44.75 wt%) were obtained after 0.5 mol/L hydrochloric acid treatment. [ABSTRACT FROM AUTHOR]

The Incoloy 945 nickel-based corrosion-resistant alloy was subjected to a low-temperature solid solution with a two-step aging process to fabricate a bimodal grain structure. The study investigated the mechanism behind the formation of the bimodal grain structure and its impact on mechanical properties. The results show that numerous clusters of fine grains, with an average size of 4 μm, were formed among the normal grains, which had an average size of 23 μm. The precipitation behavior in fine-grain clusters differs from that in normal grains. A high density of rod-like δ phases tends to precipitate inside refined grains. The inhomogeneous precipitation of δ phases is the main reason for the formation of fine-grain clusters because they have a strong ability to pin the grain boundaries for the growth of new recrystallized nuclei. The morphology of γ' varies from short rod-like particles to spherical particles depending on their location in fine-grain clusters or normal grains. The difference in precipitation and grain structure leads to different deformation mechanisms in the two regions. The bimodal grain structure results in higher strength and work hardening rate during tension. The quasi-in-situ tensile test indicates that slip transfer is more easily induced in fine-grain clusters. Fine grains had an advantage in accumulating necessary geometric dislocations during deformation, resulting in a high work hardening rate for this bimodal grain structure sample. • Bimodal grain structure with fine grain clusters formed during the two-step aging. • Inhomogeneous precipitation of δ phase causes the formation of fine grain cluster. • Segregation of Nd atoms is responsible for bimodal grain structure. • Change of precipitation behavior enhance work hardening rate in fine grain clusters. [ABSTRACT FROM AUTHOR]

Highlights • p ompT gene is likely to play an important role in the virulence of APEC strain E058. • λ red recombination system have side-effects on E. coli mutant construction. • An unexpected transcriptome pompTʹ emerged in mutant E058Δp ompTʹ. • Pathogenicity of E058Δp ompTʹ was higher than that of E058Δp ompT. Abstract The lambda red recombination system makes it suitable for screening virulence gene utility in avian pathogenic Escherichia coli (APEC) on account of its wide applicability, simplicity and high efficiency. In APEC E058 (O2 serogroup), there are two copies of the outer membrane protease (ompT) gene, c ompT encoding cOmpT that is located on the chromosome and p ompT encoding pOmpT that is located on a ColV plasmid. However, the relationship between pathogenesis and p ompT expression in APEC E058 has yet to be elucidated. Here, we successfully constructed two p ompT gene mutants: E058Δp ompT containing a chloramphenicol (cat) resistance gene and E058Δp ompTʹ without the cat gene. By RT-PCR and sequencing analysis, an unexpected transcriptome p ompTʹ was detected in mutant strain E058Δp ompTʹ after deletion of the cat gene induced by the lambda red recombination system. Surprisingly, the pathogenicity of mutant E058Δp ompT was significantly attenuated compared to its parental strain in the chicken infection model and HD11 cell model then the p ompT gene was knocked out, while the pathogenicity of the other mutant strain E058Δp ompTʹ had no difference. Furthermore, the presence of unexpected transcriptome p ompTʹ influenced the bactericidal activity of SPF chicken serum and decreased the transcription level of TLR2 in the heart tissue of chickens. Our study identifies the p ompT gene plays an important role in the virulence of APEC E058, and the unexpected transcriptome p ompTʹ contributes to the increased pathogenicity of APEC E058 mutants following deletion of the cat gene induced by the lambda red recombination system, which suggests that this system still has some limitations for construction of mutant strains particularly where these are used in development of live vaccine. [ABSTRACT FROM AUTHOR]

AA2099 Al-Cu-Li alloys were rolled by both asymmetrical and conventional rolling to a total thickness reduction of 80% at room temperature. Microstructure and texture evolution through thickness of rolling sheets were comprehensively investigated. Results show that large shear stress in ASR sample gave rise to a distortion of grain structure and a remarkable work hardening at region close to fast rolled surface. Shear banding behavior was largely promoted by ASR and various types of shear bands with higher density were observed. The shear bands triggered a kink of grain structure during rolling process. The kink behavior was related to the tilt angle and width of shear bands. The shear bands exhibited large tilt angle and width gave rise to a more significant kink of the grain structure nearby. Recrystallization during subsequent annealing was also promoted by ASR. Shear bands became favorable nucleation sites for rolled material. Growth advantage of some nuclei inside shear bands had a stronger influence on the recrystallized texture in AA2099 rolled sheets. • Asymmetrical rolling brought inhomogeneous microstructure and texture through thickness. • Grain structure was kinked into several parts due to formation of shear band. • Kink behavior is depended on the direction and the width of shear bands. • Shear banding nucleation triggers uncommon recrystallized texture during annealing. [ABSTRACT FROM AUTHOR]

Molecular separation of dye mixtures containing the same charge remains a challenge. In the present study, we prepared a composite membrane that could efficiently separate anionic dye mixtures. Briefly, Al-Metal-organic framework (Al-MOF) nanoparticles synthesized by the ion-exchange method were used as fillers during the in-situ synthesis of ethanolamine (ETA) grafted polyacrylonitrile (PAN) membrane. The optimized composite membrane showed a high rejection of congo red (CR) from a single solution (96% rejection) and the CR/methyl orange (MO) mixture (93%/18%) solution. The flux of dye mixture solution reached 180 L m−2 h−1, higher than many reports in the literature. The further modification on pore size (heat treatment) or surface charge (hydrolysis treatment) improved the membrane performance to separate smaller dye mixture of methyl blue (MB)/MO. Both modified membranes showed a good MB rejection (93%) and flux of 70–85 L m−2 h−1. While for the separation of the MB/MO mixture, the heat-treated membrane showed the lowest flux and a middling rejection. The surface hydrolyzed membrane showed a better selectivity (96% MB/32% MO) and a higher flux (127 L m−2 h−1) than that of the entirety hydrolyzed membrane (93% MB/58% MO and flux of 78 L m−2 h−1), which was attributed to their different charge distribution. Image 1 • Al metal-organic framework prepared by ion-exchange method was used as filler. • Congo red/methyl orange mixture was separated by the composite membrane. • Membranes modified by pore size or charge separate methyl blue/methyl orange. • Charge distribution of membrane greatly affects its dye separation performance. [ABSTRACT FROM AUTHOR]