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Titanium alloy is a crucial structural material in the modern aerospace field due to its strong corrosion resistance and strength, low density, and reduced sensitivity to vibration load and impact load, as well as its ability to resist expansion in the case of cracks. However, during high-speed cutting of titanium alloy, it is prone to periodic saw-tooth chip formation, which can cause high-frequency fluctuations in the cutting force, aggravate the vibration of the machine tool system, and ultimately reduce the tool’s service life and the workpiece’s surface quality. In this study, we investigated the influence of the material constitutive law in modeling the Ti-6AL-4V saw-tooth chip formation and proposed a joint material constitutive law JC-TANH which was developed based on the Johnson–Cook constitutive law and the TANH constitutive law. It has two advantages of the two models (JC law and TANH law), which means that it can describe the dynamic properties accurately, the same as the JC model, not only under low strain but also under high strain. The most important thing is that it does not need to fit the JC curve at the early stage of strain changes. Additionally, we established a developed cutting model, which integrates the new material constitutive, and the improved SPH method to predict chip morphology, cutting and thrust forces which are collected by the force sensor; we also compared the data with experimental results. Experimental results show that this developed cutting model can better explain the shear localized saw-tooth chip formation and correctly estimate its morphology as well as the cutting forces.

Calcium–magnesium–alumina–silicate (CMAS) attack is a crucial issue for thermal–environmental barrier coatings (T/EBCs) with the ever-increasing operating temperature of turbine engines. In this study, CeO2 has been demonstrated as a promising protective material for T/EBCs against CMAS attack. At 1300 °C, CeO2 powder kept excellent phase and structural stability in molten CMAS; there were some CMAS constituents dissolved into the CeO2 lattice to form a solid solution. With higher CeO2 contents and longer duration time, more CeO2 solid solution particles were formed, which acted as the nucleating agent for CMAS crystallization. As a result, apatite, anorthite and wollastonite crystalline products were easily generated. At 1300 °C for 10 h, CeO2 pellets covered with CMAS powder had limited degradation, which was attributed to the rapid crystallization of molten CMAS due to the excellent nucleating agent effect of the precipitated CeO2 solid solution.

Massive amounts of biogas slurry are produced due to the development of biogas plants. The pollution features and the risk of biogas slurry were fully evaluated in this work. Thirty-one biogas slurry samples were collected from sixteen different cities and five different raw materials biogas plants (e.g. cattle manure, swine manure, straw-manure mixture, kitchen waste and chicken manure). The chemical oxygen demand (COD), ammonia nitrogen ( NH 4 + - N ), anions (e.g. Cl−, SO 4 2 - , NO 3 - and PO 4 3 - ), antibiotics (e.g. sulphonamides, quinolones, β2-receptor agonists, macrolides, tetracyclines and crystal violet) and heavy metals (e.g. Cu, Cd, As, Cr, Hg, Zn and Pb) contents from these biogas slurry samples were systematically investigated. On this basis, risk assessment of biogas slurry was also performed. The concentrations of COD, NH 4 + - N and PO 4 3 - in biogas slurry samples with chicken manure as raw material were significantly higher than those of other raw materials. Therefore, the biogas slurry from chicken manure raw material demonstrated the most serious eutrophication threat. The antibiotic contents in biogas slurry samples from swine manure were the highest among five raw materials, mostly sulphonamides, quinolones and tetracyclines. Biogas slurry revealed particularly serious arsenic contamination and moderate potential ecological risk. The quadratic polynomial stepwise regression model can quantitatively describe the correlation among NH 4 + - N , PO 4 3 - and heavy metals concentration of biogas slurry. This work demonstrated a universal potential threat from biogas slurry that can provide supporting data and theoretical basis for harmless treatment and reuse of biogas slurry.

Improving the biodegradation efficiency of terephthalic acid (TA) wastewater processes is highly challenging, particularly in large-scale up-flow anaerobic sludge blanket (UASB) reactors.

In this work, Friedel-Crafts alkylation was successfully applied to prepare a magnetic ionic liquid hypercrosslinked polymer composite (Fe

effects of HHP on the texture properties of eel surimi, eel myofibrillar protein (MP) structure, and angiotensin-converting enzyme (ACE) inhibitory activity were studied. In this study, eel surimi samples were treated with HHP at 100, 200, 300, 400, 500, and 600 MPa. Texture profiling analysis results of eel surimi under HHP (> 400 MPa) showed that the hardness, adhesiveness, and chewiness of surimi had significantly increased compared to control, which greatly improved the quality of surimi. HHP could convert the α-helix and β-sheet to random coil and β-turn, enhancing the contents of the interior hydrophobic and reactive sulfhydryl groups. The hardness, adhesiveness, chewiness, and springiness of surimi showed a negative relationship with the α-helix and β-sheet, and a positive correlation with random coil and β-turn. The ACE inhibitory activity of MP after HHP treatment increased, and the ACE inhibitory activity was highly (76.9%) observed at 300 MPa, which was increased by 16.5% compared with that of the control group. A positive relationship between the hydrophobic and ACE inhibitory activity of MP, and a negative relationship with the β-sheet structure were observed. The overall results suggested that structurally induced changes can be a major cause of the significant enhance of texture of surimi and ACE inhibitory activity of MP under HHP.

Amorphous and irregular nanoparticles of CoSx were anchored on regular CaTiO3 nanocubes by the method of in situ growth, and the S-scheme heterojunction for photocatalytic hydrogen production was c...

In this study, a new method comprising graphene oxide (GO) and amino group modifications of carbon felt (CF) electrode material surfaces was employed to improve the initial adhesion capacities of b...

An effective method to reduce the recombination rate of photogenerated electron–hole pairs was developed by the construction of heterojunctions with rationally designed photocatalysts having a matched band structure. Herein, g-C3N4 hexagonal tubes possessing a lower conduction band were coupled with Co3S4 ultra-fine nanoparticles having relatively higher positions for their conduction band. A step-scheme heterojunction was constructed between these two materials, and through this heterojunction, the spatial charge separation was boosted. The boosted spatial charge separation led to more useful electrons with a higher reduction ability that participated in a photocatalytic H2 evolution reaction. The Co3S4 ultra-fine nanoparticles act as a mirror to repeatedly scatter and reflect incident light and thus enhance light utilization, and they also accelerate the spatial charge separation. The photocatalytic H2 evolution activity of the composite catalyst reached 2120 μmol g−1 h−1, which was 176 times higher than that of pristine g-C3N4 tubes. A series of characteristics were determined to investigate the interaction that occurred between the g-C3N4 hexagonal tubes and the Co3S4 ultra-fine nanoparticles, and to study the mechanism of the formed step-scheme. This work will guide the design of step-scheme heterojunction-based photocatalysts to produce H2 from photocatalytic water splitting.

Hydrogen production from water splitting is considered as a brand-new and promising way to convert solar energy into recyclable chemical energy. Herein, a core–shell-shaped structure which consisted of Mn0.05Cd0.95S nanorods and flowerlike NiAl-LDH microsphere was constructed via a simple hydrothermal method. The constructed Mn0.05Cd0.95S/ NiAl-LDH core–shell-shaped structure shows superior photocatalytic H2 evolution. The highest photocatalytic H2 evolution rate of the composite is 7.5 mmol g−1 h−1, which is 17 and 6 times higher than those of NiAl-LDH and Mn0.05Cd0.95S respectively. The core–shell like structure is beneficial for the H2 production reaction because NiAl-LDH flowerlike microsphere can provide large surface for the anchoring of Mn0.05Cd0.95S nanorods, which can enhance the interaction between these two materials. A series of characterizations including XRD, FT-IR, SEM, TEM, BET, XPS, UV−vis DRS, etc., were conducted and studied to analyze the reason for the enhanced photocatalytic hydrogen evolution activity. The results of XPS show that an interaction between NiAl-LDH and Mn0.05Cd0.95S has been occurred. The interaction between these two materials is presented through the transfer of electrons, which can be demonstrated by the results of XPS. And, it is found that the rational designed structure can accelerate the transfer of electrons and this is the reason for the enhanced photocatalytic evolution performance. A core-shell like structure consisted of Mn0.05Cd0.95S nanorods and NiAl-LDH nanoflower like sphere was designed rationally via a simple method. The NiAl-LDH nanoflower like sphere with some wrinkles on its surface can provide more areas to contact with Mn0.05Cd0.95S nanorods, which can is beneficial for the interaction between these two materials and accelerate the transfer of electrons.

A mathematical model is developed in this study to simulate the performance and fates of carbon (C), nitrogen (N) and phosphorus (P) in wet and high-total solid (TS) anaerobic digestion (AD) processes. The “Anaerobic Digestion Model No. 1” (ADM1) is improved by adding inorganic components and integrating the inhibition of high-TS and liquid-solid processes. The model's outputs are validated with experimental results obtained from a semi-continuous reactor, with pig manure as a single substrate at wet and high-TS operation stages. The predicted C (methane production and volatile fatty acid concentrations), N (ammonia nitrogen concentrations) and P (phosphorus concentrations) fates are reasonable and exhibit good accuracy. The model is subsequently applied to simulate CH4 production under different hydraulic retention times and organic loading rates. The simulation analysis demonstrates that pret-reatments, such as promoting the hydrolysis and biodegradility of substrate and immobilising strains, are necessary in the high-TS AD process for pig manure to enhance performance. This study provides guidance for the future optimisation of process and nutrient recycling in AD.

Hydrogen production from photocatalytic water splitting has been considered as a promising way to convert solar energy into chemical energy. Herein, a novel photocatalyst was synthesized successful...

The photocatalytic decomposition of water to produce hydrogen is an important process, through which solar energy can be converted to chemical energy. Non-precious metal phosphides have quietly attracted attention as an emerging inexpensive photocatalyst. In this study, we reported that a CoP/CeVO4 hybrid photocatalyst exhibited high hydrogen evolution efficiency owing to EY (eosin Y) sensitization under visible light irradiation for the first time, and the amount of generated hydrogen reached 444.6 μmol in 5 h. The CoP/CeVO4 nanohybrids were synthesized by a simple chemical precipitation method. The coupling of CoP and CeVO4 with ZIF-9 as a precursor could be completed in one step. The CeVO4 particles were firmly attached to the surface of the CoP particles to form a “small point” to “big point” heterojunction. The results of X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, EDX, and transmission electron microscopy showed the formation of CoP and CeVO4 nanoparticles and the structure of the composite. Based on a detailed analysis of the Mott-Schottky plot, the UV-vis diffuse reflectance spectra, photocurrent-time (it) curve, Tafel curve, Nyquist curve (EIS), linear volt-ampere curve (LSV), and steady-state fluorescence spectra were studied. The time-resolved photoluminescence measurements indicated that the reason for the high-efficiency hydrogen evolution of CoP/CeVO4 was that the bands of CoP and CeVO4 were bent due to the existence of the Schottky barrier, and a heterojunction was formed between CoP and CeVO4, which generated an internal electric field and accelerated the charge transfer. In addition, the synergistic effect between CoP and CeVO4 provided a new hydrogen-evolution activity center for each of them. The improved carrier separation efficiency and the decrease in the photo-generated recombination rate led to the excellent photocatalytic hydrogen-evolution activity of the CoP/CeVO4 composite catalyst. This work provides a new strategy for modulating the electronic structure and carrier behavior of transition metal phosphide photocatalysts.

One-dimensional hierarchically superstructured metal-doped titanate and TiO2 materials with coated-nanosheet and interconnected meso-/macropores have been successfully constructed via a general strategy based on the self-evolution of building blocks. The as-fabricated superstructured TiO2-based fibers exhibited remarkable stable cycling performance at a high current rate (5C) in lithium–sulfur (Li–S) batteries.

Insulin administration at mealtimes for the control of postprandial glucose is a major part of basal-bolus insulin therapy; however, painful subcutaneous (SC) injections lead to poor patient compliance. The microneedle (MN) patch, which allows painless transdermal drug delivery, is a promising substitute; however, it remains a big challenge to deliver insulin as rapidly as by SC injection. Here a novel MN patch is designed in which the MNs are coated with insulin/poly-l-glutamic acid (PGA) layer-by-layer (LBL) films at pH 3.0. This coating is pH-sensitive because the net charge of insulin turns from positive to negative when the pH increases from 3.0 to 7.4. As a result, when transferred to pH 7.4 media, e.g., when inserted into skin, the coating dissociates instantly and releases insulin rapidly. A brief epidermal application (

In this study, an integrated and assembled recyclable biofilm material was prepared by loading Herminiimonas arsenicoxydans (H. arsenicoxydans) onto electrospun biomass-activated carbon nanofibers (denoted as H. arsenicoxydans-BACFs films). The H. arsenicoxydans-BACFs biofilms showed an approximately 50% increase in As(III) removal rate for 50 mg/L during a 48-h incubation. Furthermore, the biofilms demonstrated satisfactory biocompatibility, ideal catalytic As(III) oxidation and excellent recyclability in cyclic reactions (at least 5 runs). The improved catalytic efficiency is mainly due to a large amount of biomass accumulation and biofilms formation on the surface of the BACF films. More important, the BACF films as an electron transport medium from an oxidized state to a reduced state promote the electron transfer of As(III) oxidation of H. arsenicoxydans. The dual factors can synergistically promote As(III) oxidation efficiency. The oxidation process of As(III) in the H. arsenicoxydans-BACFs composite biofilm reactor was more in line with the first-order kinetic equation, and the oxidation rate of As(III) by H. arsenicoxydans-BACF

Microbe-photocatalyst biohybrids, integrating the optimal attributes of whole-cell catalysts and nanometer photocatalysts, have emerged as a promising strategy for environment-associated applications. However, few such biohybrids have been tested for complex pollution systems. Herein, we constructed an outer membrane photosensitized Geobacter sulfurreducens (G. sulfurreducens)-CdS biohybrid, which enabled to generate stronger photocurrent in response to irradiation and meanwhile achieved an significant promotion for the redox transformation of Cr(VI) and tetracycline compared with that of bare G. sulfurreducens or CdS counterparts. Further analysis revealed that the outer membrane played a significant role in photoelectron transfer. Differential pulse voltammetry (DPV) tests demonstrated that CdS enhanced the catalytic activity of C-type cytochromes on the outer membrane under irradiation, resulting in the increase of electron-hole pairs separation efficiency. The possible degradation pathway of tetracycline was proposed based on determined intermediates, whose toxicities were well evaluated. Importantly, the toxicity of the final detected intermediates was apparently decreased. Overall, this work aims to explore the working mechanisms of the novel G. sulfurreducens-CdS biohybrid system and opens up a new avenue to purifying combined wastewater by microbe-photocatalyst biohybrids.

Ara h 1 is recognized as a major peanut allergen. The effects of high hydrostatic pressure (HHP) on the immunoreactivity and structure of Ara h 1 were investigated in this study. The immunoreactivity of Ara h 1 was considerably reduced (P

Background: To investigate the effect of polyunsaturated fatty acids ω-3 and ω-6 and their metabolites prostaglandin PGE2 and PGE3 on the proliferation, invasion and neovascularization of gastric cancer.Methods: RT-PCR and ELISA were used to detect the gene and protein expression of COX-1 and COX-2 in gastric cancer cell lines, respectively. The effects of ω-3, ω-6, PFG2 and PEG3 on the proliferation, invasion and neovascularization of gastric cancer cells were detected by cell proliferation, invasion and neovascularization assay in vitro. COX-2 siRNA was synthesized by short gene interfering RNA (siRNA) technique and transfected into gastric cancer cells, and the expression of COX-2 protein in gastric cancer cell lines was detected again by Western blot. The effects of COX-2 gene silencing on proliferation, invasion and neovascularization of gastric cancer cells were detected by WST-1 assay, transwell chamber assay and gastric cancer neovascularization assay, respectively.Results: COX-2 was only expressed in MKN74 and MKN45 cell lines, while COX-1 was expressed in four gastric cancer cell lines. In gastric cancer cell lines with positive COX-2 expression, ω-6 and PEG2 could significantly enhance the proliferation, invasion and neovascularization of gastric cancer cells, and after transfection with COX-2 siRNA, the effects of ω-6 and PEG2 on enhancing the proliferation, invasion and neovascularization of gastric cancer cells were significantly attenuated; ω-3 and PEG3 could inhibit the proliferation, invasion and neovascularization of gastric cancer cells. In gastric cancer cell lines with negative COX-2 expression, ω-6 and PEG2 had no significant effect on the proliferation, invasion and neovascularization of gastric cancer; ω-3 and PEG3 could significantly inhibit the proliferation, invasion and neovascularization of gastric cancer.Conclusion: ω-6 PUFAs reinforce the metastatic potential energy of gastric cancer cells via COX-2/PGE2; ω-3 PUFAs inhibit the metastatic potential energy of gastric cancer via COX-1/PGE3.