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• Mechanical properties of superconducting magnet insulation materials after reheat. • Strain responses during second Vacuum Pressure Impregnation process. • Monitoring by Fiber Bragg Grating sensors embedded in the insulation layers. • Additional strain introduced by the new added epoxy resin. In large-scale, high-field superconducting magnets used for magnetic confinement fusion, high energy accelerators, and magnetic resonance imaging, the insulating system made from glass fiber reinforced resin-based composites is the key component, which mainly plays the role of mechanical support, fixing and protecting superconducting conductors, as well as electrical insulation. Vacuum Pressure Impregnation (VPI) approach is widely used in the manufacturing of the insulation system. The second curing cycle is generally required after the first VPI and curing process. For example, after the superconducting coil is cured in the mold, the de-molding process requires the superconducting coil to be reheated according the curing temperature. Moreover, for large-scale superconducting magnets, the superconducting coil needs to undergo a second VPI process after the first VPI process to fix the coil in the coil case. In this work, the tensile and shear properties of pure epoxy resin and the glass fiber reinforced resin-based composite, were investigated at both room and cryogenic temperatures and the effect of the second curing cycle on the mechanical properties was analyzed. Additionally, the strain evolution of the Nb-Ti superconducting coil during the second curing cycle was measured using the Fiber Bragg Grating (FBG) sensors embedded in the composite. The results indicate that the second curing cycle will not introduce additional strain to the previously cured resin matrix, but the defective or weak parts of the resin matrix may be affected by the new added epoxy resin and a little extra strain has been observed. [ABSTRACT FROM AUTHOR]

• Steady-state simulation for cryogenic distillation of helium isotope separation is conducted. • The profiles of 3He and 4He contents, temperature, vapor–liquid flow rates within column and duties of condenser and reboiler is simulated. • A sensitivity analysis is investigated with respect to the feed concentration of 3He and reflux ratio. Helium-3 (3He) is an invaluable and scarce resource with applications in various scientific and industrial fields. It is typically found mixed with helium- 4(4He) in natural gas and nuclear off-gas, which is industrial source of helium. Therefore, separation of the helium isotope is necessary. Cryogenic distillation is a preferred method of separation due to its higher separation coefficient and processing capacity. In this study, a numerical steady-state simulation of cryogenic distillation column for helium isotope has been conducted using programming. The mathematical model for the equilibrium-state cryogenic distillation process was established and solutions of the thermodynamic formulation was proposed. The simulation provided the distribution of 3He and 4He along each distillation column as well as the profiles of temperature and flow rates along the column, based on the designed specifications including the composition of the feeding mixture, feed flow rate and pressure. The required heat duty of the condenser and reboiler was also calculated, and the column dimensions were estimated. Besides, we have studied the effects of the reflux ratio and feed concentration of 3He on the final isotopic contents of the top and bottom products. The results demonstrated that the distillation simulation could provide crucial theoretical support for the smooth execution of future laboratory experiments. [ABSTRACT FROM AUTHOR]

Abstract: The direct production of methyl, ethyl and n-butyl carbamates (MC, EC and BC) from NH3, CO2 and alcohols could efficiently be catalyzed by V2O5, and ca. 11–25% yields with 98% selectivity for alkyl carbamates could be obtained. The catalyst could be recycled six times without obvious decrease in catalytic activity. XRD and XPS analysis showed that in-situ produced (NH4)2V3O8 was the catalytically active species. [Copyright &y& Elsevier]

A pile-restrained floating wave energy converter (WEC) array is proposed as an alternative to a single floater of the size of the array for use as a floating breakwater. The hydrodynamics of the WEC are modelled based on the Navier-Stokes equations and the model is verified by comparing its results with existing experimental data. The model then is used to characterize the array composed by a line of three WECs in terms of floater heaving, wave energy conversion, wave reflection, transmission and dissipation, for different layouts. In the examined array configuration, the aligned arrays exhibit superior performance compared to the staggered arrays, comprehensively considering both wave energy conversion and wave transmission. Specifically, when kh i > 1.73, the wave energy conversion efficiency of the aligned array with a spacing of 0.1 times the WEC width ranges from 0.141 to 0.330, while the wave transmission coefficient ranges from 0.187 to 0.472, indicating the effectiveness of the arrays in simultaneously reducing wave transmission and converting wave energy under shorter-wavelength conditions. Compared to a single WEC of the same dimensions, the array exhibits a remarkable increase in wave energy conversion efficiency and effectively reduce wave reflection. [ABSTRACT FROM AUTHOR]

Research about magnesium corrosion inhibitors focuses on their influence on corrosion rate, but little attention is paid to whether the service reliability of alloys is improved by the inhibitors. In this work, the effects of selected corrosion inhibitors on the corrosion rate and localized corrosion behavior of magnesium alloy were compared. It is found that some corrosion inhibitors fail to inhibit the localized corrosion of magnesium, resulting in the inability to effectively maintain the mechanical bearing capacity of the corroded magnesium alloy. This study is of great significance for establishing reasonable screening and evaluation criteria for magnesium alloy corrosion inhibitors. • SDBS and PDCA effectively slows down the corrosion rate of Mg alloy but cannot completely inhibit localized corrosion. • SA slightly accelerates Mg corrosion but delays the decline of mechanical properties of alloy. • PCCys significantly slows down the corrosion rate and inhibit the localized corrosion of Mg alloy. • Inhibition efficiency of corrosion inhibitor has no direct link to its effect on the mechanical bearing capacity of Mg alloy. [ABSTRACT FROM AUTHOR]

The up-flow anaerobic sludge blanket (UASB) reactor for treating starch wastewater exhibits poor resistance to organic loading rate shocks and low efficiency in biomethane recovery. This study proposed a solution to address this issue by using oyster shells as an alternative conditioner. Results indicated that the UASB reactor with oyster shells conditioning exhibited a significant increase in methane production from 243 to 435 mL/g-chemical oxygen demand (COD) removed , as the organic loading rate increased from 2.5 to 7.1 kg-COD/(m3·d). This value surpassed that of the control reactor, which experienced a sharp decline in performance. Furthermore, it also exceeded the majority of reported methane yields ranging from 150 to 330 mL/g-COD removed. The pH adjustment and additional supply of carbon dioxide from oyster shells was primarily responsible for the substantial increase in methane production. Moreover, oyster shell conditioning resulted in improvements in specific methanogenic activity, extracellular polymeric substances protection, and settling capacity of anaerobic granular sludge, as well as the enrichment in Methanosaeta abundance, and strengthening of methanogenic functional activity. All these factors contributed to the successful methanogenesis of starch wastewater in UASB reactor through oyster shell conditioning. These findings highlighted the potential of using oyster shells as a favorable conditioner for optimizing UASB treatment of easily acidified wastewater (e.g., starch wastewater), which presented promising practical applications. [Display omitted] • Methane yield reached 435 mL/g-COD removed through oyster shells conditioning. • The significantly improved SAA accounted for the enhanced methane yield. • The settling capacity of AGS was improved through oyster shells conditioning. • UASB became much more stable with Methanosaeta predominating at 69 %. • Oyster shells conditioning had positive application in starch wastewater treatment. [ABSTRACT FROM AUTHOR]

• NA can be used as reactive alumina resource in cement paste. • Influence of NA on the chloride binding capacity of blended cement pastes were investigated. • NA is beneficial for improving the chloride binding capacity of cement paste blended with SCMs. Chloride ingress is one of the main causes for the degradation of reinforced concrete structures. Increasing the chloride binding capacity of concrete is generally thought as a feasible way to restrain the chloride ingress. In our previous study, the γ-phase nano-Al 2 O 3 (NA) was found to be beneficial for improving the chloride binding of plain Portland cement paste as a result of the formation of additional Friedel's salt. Herewith, the cases of blended cement pastes were further investigated, into which supplementary cementitious materials (SCMs) were incorporated, including fly ash (FA), blast furnace slag (SL) and silica fume (SF). NA with a dosage of 1% and 2% was introduced to blended cement paste, and the chloride binding capacity of which were determined with the conventional equilibrium method. The results showed that the use of NA was even viable to improve the chloride binding capacity of blended cement pastes. X-ray diffraction (XRD)/Rietveld refinement method and thermogravimetric analysis (TGA) were performed to unravel the phase assemblages change upon exposure. It was revealed that besides the formation of more Friedel's salt, the addition of NA could allow the enhanced physical binding of chloride as a result of the formation of C-A-S-H, i.e., the substitution of Si by Al in C-S-H gel. [ABSTRACT FROM AUTHOR]

• The radiation forces exerted on the redundant particles by an incident Gaussian laser beam are derived. • The analytical expressions of the axial RFs and the transverse RFs are provided. • The variations of the axial and transverse components of RFs with are numerically analyzed. • The influences of the beam waist widths, radius, refractive index, and off-axial distance are researched. The effective removal of micro-/nanometers redundant particles is a challenging problem for improving the optical surface performance and reliability. The radiation forces(RFs) exerted on the redundant particles by an incident Gaussian laser beam are derived on the basis of generalized Lorenz-Mie theory combining with the scattering theory. The analytical expressions of the axial RFs and the transverse RFs are provided according to the relationship between spherical vector wave functions and triangle functions. The variations of the axial and transverse components of RFs with the beam waist widths, radius, refractive index, and off-axial distance are numerically analyzed. The results provide a theoretical and technological basis for clearing and controlling the redundant particle more efficiently in the nondestructive examination project. [ABSTRACT FROM AUTHOR]

Highlights • Recycled sand was used to develop UHPCCs. • Mixtures of UHPCCs with recycled sand were designed via linear packing model. • 5 UHPCCs were designed with different replacement percentages of recycled sand. • Compressive strength of UHPCCs with recycled sand was up to 170.0 MPa. • Replacement rate of recycled sand in UHPCCs was recommended under 50%. Abstract Due to the excellent mechanical and durability properties, ultra-high performance cement-based composites (UHPCCs) have attracted a lot of attention during the past decades. It is noted that most existing UHPCCs are manufactured from raw materials with high quality, for instance, well-graded river sands. However, the huge consumption of river sands as construction materials has inevitably resulted in some serious ecological impacts, as reported around the world. In this regard, it shall be much beneficial if some substitutes, such as recycled sands produced through processing of construction and demolition waste (CDW), could be used to replace natural sands to manufacture the qualified UHPCCs. This paper presents such a preliminary study on the feasibility of manufacturing UHPCCs with recycled sands. A total of five UHPCCs are designed and cast with different replacement percentages of recycled sand, i.e., 0%, 30% 50%, 70% and 100% (in mass). The associated packing density of the mixed sands is estimated based on the linear packing model. The fresh and hardened properties of the UHPCCs, including the workability, strength and shrinkage, are experimentally examined. The test results indicate that it is possible to use recycled sand to replace natural river sand in the manufacture of UHPCCs; however, the amount of the recycled sand needs to be limited. In the case when the replacement percentage of the recycled sand is lower than 50% (in mass), the properties of the UHPCCs with the recycled sand are comparable with those containing river sand only. [ABSTRACT FROM AUTHOR]

Abstract Bacterial infections cause acute and chronic diseases. Antimicrobial resistance and aging-related immune weakness remain challenging in therapy of infectious diseases. Vaccines are however an alternative to prevent bacterial infections. Here we report a facile method to rapidly generate bacterium-membrane-formed nanovesicles as a vaccine using nitrogen cavitation. The vaccine is comprised of double-layered membrane vesicles (DMVs) characterized by cryo-TEM, biochemistry and proteomics, showing DMVs possess the integrity of bacterial membrane and contain a wide range of membrane proteins required for vaccination. In the mouse sepsis model induced by Pseudomonas aeruginosa , we found that DMVs can improve mouse survival after mice were immunized with DMVs. The increased adaptive immunity and unique biodistribution of DMVs were responsible for enhanced protection of bacterial infection. Our studies demonstrate that this simple and innovative approach using nitrogen cavitation would be a promising technology for vaccine developments. [ABSTRACT FROM AUTHOR]

Aims In order to investigate the effects and mechanism of Bisphenol A (BPA) on the growth of preantral follicles and the maturation of oocytes in vitro , preantral follicles were harvested from mouse ovaries and in vitro cultured for 11 days with different concentrations of BPA (0, 4.5 and 45 μM) for calculating the percentages of antral follicles, denuded oocytes, degenerative oocytes and the maturation rate of oocytes, besides measuring the diameter of follicles and the thickness of cumulus cell layers. Methods The contents of estradiol (E 2 ) in the culture media on Day 4, 8 and 10 were detected by ELISA. The estrogen receptor (ER) expression, spindle morphology and chromosome distribution in oocytes on Day 10 and 11 were observed by immunofluorescence. Western blotting was used to detect the expressions of growth differentiation factor 9 (GDF-9), bone morphogenetic protein-15 (BMP-15), phosphorylated extracellular signal-regulated kinase 1 (p-Erk1) and phosphorylated Ca 2 + /calmodulin-dependent protein kinase II (p-CaMKII) in the oocytes. Results Compared with control, BPA (45 μM) significantly reduced percentages of antral follicles (9.25% vs. 91.17%, P   <   0.05 ) and the maturation rate of oocytes (7.61% vs. 79.83%, P   <   0.05 ), but increased the percentages of denuded oocytes (30.29% vs. 3.36%, P   <   0.05 ) and degenerative oocytes (45.70% vs. 2.45%, P   <   0.05 ). The diameter of follicles and the thickness of the cumulus cell layers were decreased significantly ( P   <   0.05 ). Moreover, BPA (45 μM) significantly decreased E 2 contents in the culture medium on Day 8 and 10 ( P <   0.05 ) and the expressions of ER, GDF-9 and BMP-15 in oocytes ( P   <   0.05 ). Furthermore, BPA (4.5 and 45 μM) treatment resulted in the abnormal spindle morphology and chromosome distribution, and the decreased expressions of p-Erk1 and p-CaMKII in the MII oocytes. Conclusion Together, these results clearly demonstrated BPA retarded the preantral follicle growth in vitro through interfering with the synthesis and secretion of E 2 and reducing the expressions of ER, GDF-9 and BMP-15, and led to the abnormal meioses of oocytes through reducing p-Erk1 and p-CaMKII expressions in the preantral follicles, which will help us to further unsderstand the mechanism of BPA exposure retarding in vitro growth of preantral follicles and maturation of oocyes. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Optimization effect of earthworms in vermicomposting was studied by PLFA profiles. • Earthworm activity expanded the microbial community diversity in vermicomposting. • Percentages of fungi and protozoa were increased due to the presence of earthworms. • The burrowing action of earthworms improved aerobic condition of vermicomposting. Abstract In this study, the influences of earthworms on the structure of microbial community as well as the metabolic function in vermicomposting (VPs, with earthworms) for excess sludge stabilization were investigated. Comparison between the dynamic variation of PLFA profiles in VPs and common composting (CPs, with no earthworms) was conducted. The Shannon index was increased in VPs, while it was decreased in CPs with time, indicating earthworm activity enhanced microbial community diversity. The fungal and protozoal biomasses were significantly increased in VPs compared with CPs. Further researches by principal component analysis (PCA) indicated that earthworms benefited certain microorganisms containing biomarkers of 18:1ω9c, 18:3ω3, 18:3ω6, 20:1ω9, 20:2ω6 and 20:3ω6. Moreover, the ratios of monounsaturated to branched PLFAs in VPs were larger than those in CPs, suggesting the aeration condition was promoted by the burrowing behaviors of earthworms and therefore facilitated the growth and propagation of aerobic microorganisms, such as protozoa. Those results indicated that earthworm activity led to the general optimization of vermicomposting for excess sludge stabilization. [ABSTRACT FROM AUTHOR]

• PL additive had a diminishing retarding effect on cement hydration. • Appropriate dosage of PL had positive effects on the work performance of cement-based materials. • PL could increase the dispersion of cement system. The application of lignin dispersants in cementitious materials has been limited due to its strong retarding effect on cement hydration. In this study, polyaniline modified lignin (PL) was prepared to be as a new lignin additive to increase the dispersion of cement system and maintain good mechanical properties of cementitious materials. This investigation systematically revealed that different contents of PL (0%, 0.5%, 1.0%, 2.0%) had various effects on the early hydration, the work performance and the microstructure of cement paste and mortar. Appropriate dosage of PL was beneficial to achieve better dispersion and improve the fluidity of cement system. The retarding effect on cement hydration was significantly reduced by PL, compared to unmodified lignin. When the content of PL was 0.5% and 1.0%, the mechanical properties of the mortar was maintained as well as mortar without PL. However, excessive content of PL (2.0%) decreased the flexural strength and compressive strength significantly. XRD and TG tests exhibited that no new hydration products were generated and the formation of calcium hydroxide was inhibited after the addition of PL. Besides, SEM and MIP results showed that low dosage of PL could decrease the porosity due to the filling effect. When the dosage of PL in cement exceeds 2.0%, the structure was more loose and porous, attributed to the delayed hydration and air entertainment. The dispersion mechanism was also discussed and ascribed to electrostatic repulsion caused by PL adsorbed on the surface of cement particles and the steric effect due to the branched chains of PL. This study provides a new idea for high-value application of lignin and the promotion of low-carbon building materials by using renewable resources. [ABSTRACT FROM AUTHOR]

The cerium-based coatings have attracted increasing attention for modifying Mg surface in biomedical applications due to their corrosion protectiveness and potential biological effects. However, their anti-corrosion mechanisms have not been fully understood. In this work, the corrosion resistance of anodic electrodeposited cerium-based oxides coating on Mg alloy was investigated in Hanks' balanced salt solution. The obtained results demonstrate that the strengthened precipitation of protective calcium phosphate products on this coating results in its enhanced anti-corrosion nature. These findings enrich the understanding on anti-corrosion mechanisms of the cerium-based coating and point out its prospect on Mg alloys for bone implants. • Cerium-based oxides coating was prepared on Mg alloy by anodic electrodeposition. • The coating presented additional anti-corrosion properties over immersion time in HBSS. • The strengthened precipitation of protective calcium phosphate products on coating was clarified. • Anti-corrosion mechanisms of cerium-based oxides coated Mg alloys in HBSS were revealed. [ABSTRACT FROM AUTHOR]

Background Global disparities in prostate cancer (PCa) incidence highlight the urgent need to identify genomic abnormalities in prostate tumors in different ethnic populations including Asian men. Objective To systematically explore the genomic complexity and define disease-driven genetic alterations in PCa. Design, setting, and participants The study sequenced whole-genome and transcriptome of tumor-benign paired tissues from 65 treatment-naive Chinese PCa patients. Subsequent targeted deep sequencing of 293 PCa-relevant genes was performed in another cohort of 145 prostate tumors. Outcome measurements and statistical analysis The genomic alteration landscape in PCa was analyzed using an integrated computational pipeline. Relationships with PCa progression and survival were analyzed using nonparametric test, log-rank, and multivariable Cox regression analyses. Results and limitations We demonstrated an association of high frequency of CHD1 deletion with a low rate of TMPRSS2-ERG fusion and relatively high percentage of mutations in androgen receptor upstream activator genes in Chinese patients. We identified five putative clustered deleted tumor suppressor genes and provided experimental and clinical evidence that PCDH9 , deleted/loss in approximately 23% of tumors, functions as a novel tumor suppressor gene with prognostic potential in PCa. Furthermore, axon guidance pathway genes were frequently deregulated, including gain/amplification of PLXNA1 gene in approximately 17% of tumors. Functional and clinical data analyses showed that increased expression of PLXNA1 promoted prostate tumor growth and independently predicted prostate tumor biochemical recurrence, metastasis, and poor survival in multi-institutional cohorts of patients with PCa. A limitation of this study is that other genetic alterations were not experimentally investigated. Conclusions There are shared and salient genetic characteristics of PCa in Chinese and Caucasian men. Novel genetic alterations in PCDH9 and PLXNA1 were associated with disease progression. Patient summary We reported the first large-scale and comprehensive genomic data of prostate cancer from Asian population. Identification of these genetic alterations may help advance prostate cancer diagnosis, prognosis, and treatment. [ABSTRACT FROM AUTHOR]

This study firstly evaluated the microbial role when choosing the acclimated anaerobic granular sludge (AGS) and waste activated sludge (WAS) as microbial and nutritional regulators to improve the biomethanation of fruit and vegetable wastes (FVW). Results showed that the enriched hydrogenotrophic methanogens, and Firmicutes and Spirochaeta in the AGS were responsible for the enhanced methane yield. A synthetic waste representing the mixture of WAS and FVW was then used to investigate the influences of different substrate composition on methane generations. The optimal mass ratio of carbohydrate/protein/cellulose was observed to be 50:45:5, and the corresponding methane yield was 411 mL/g-VS added . Methane kinetic studies suggested that the modified Gompertz model fitted better with those substrates of carbohydrate- than protein-predominated. Parameter results indicated that the maximum methane yield and production rate were enhanced firstly and then reduced with the decreasing carbohydrate and increasing protein percentages; the lag phase time however increased continuously. [ABSTRACT FROM AUTHOR]

With coupled mechanical-chemical field, the predominant role of fatigue crack evolution and tribo-chemistry on Si-DLC films were investigated under different relative humidity. Results show that incorporating Si stabilized friction interface and induced lubricating carbonaceous material transfer (0.053 under 20% RH), but the lubricating effect was deteriorated (0.12) by the iron oxide products on sliding shear stress. Furthermore, Si element aggravate overall wear rates than DLC film. Increasing relative humidity was beneficial to lowering wear rates of films with lower Si content, but aggravated the wear rates of films with higher Si content. The predominant role of tribo-chemistry on the friction coefficient (COF) was confirmed, meanwhile, critical impact of fatigue cracks evolution on surface wear is worse than that of tribo-chemistry. • Incorporating Si induced lubricating carbonaceous transfer, but the iron oxide products deteriorated lubricating effect. • Increasing relative humidity reduced wear rates of lower Si films, but aggravated the wear rates of higher Si films. • The fatigue cracks evolution of Si-DLC films was consistent with the increasing wear rates of Si-DLC films. [ABSTRACT FROM AUTHOR]

[Display omitted] • MgAlO x oxides derived from LDHs was used as support for high active NH 3 -SCR catalyst. • The highly dispersed MnO x on support were prepared by incipient wetness impregnation. • The novel catalysts exhibited superior low-temperature activity and N 2 selectivity. • The optimal catalyst MnA/MgAlO x -800 showed remarkable resistance to H 2 O. A series of novel highly dispersed MnO x on the MgAlO x support derived from layered double hydroxides (LDHs) were successfully prepared by incipient wetness impregnation method for low-temperature selective catalytic reduction of NO x with ammonia (NH 3 -SCR). The physicochemical properties and the catalytic performance of the prepared samples with different Mn precursor salt (acetate, nitrate and sulfate) and varying calcination temperatures of MgAlO x support were systematically investigated. The optimal catalyst, MgAlO x calcined at 800 °C with impregnating manganese acetate (denoted as MnA/MgAlO x -800), exhibited superior denitration performance, with NO x conversion over 80 % in the temperature range of 100–300 °C as well as remarkable resistance against H 2 O. The proper supports MgAlO x not only provided large specific area for the dispersion of the Mn, but also supplied more adsorption sites for reactant molecules. It was also found that the interaction between Mn species and MgAlO x support induced the higher concentration of Mn4+ and chemisorbed oxygen species. As suggested from in situ DRIFTs analysis, Lewis acid sites promoted the adsorption and activation of NH 3 , which facilitated the NH 3 -SCR reaction to proceed. Furthermore, E-R mechanism was proposed in the SCR reaction, evidenced by in situ DRIFTS study. [ABSTRACT FROM AUTHOR]

[Display omitted] • Corrosion of the substrate was effectively inhibited by the presence of MgSO 4 during coating preparation. • MgSO 4 results in the transformation of the middle calcite from cubic to spindle-shaped crystals. • Mg2+ and SO 4 2− promote the precipitation of metastable aragonite and vaterite in the outer layer. • The corrosion resistance of CaCO 3 coating for Mg substrate can be adjusted by MgSO 4 concentration. • CaCO 3 could be transformed into Ca-P products during immersion. Too fast corrosion of magnesium(Mg)-based materials is one of main concerns prior to their applications as biodegradable biomaterials. In present study, a CaCO 3 coating on Mg alloy is developed via hydrothermal method to control the corrosion of Mg2Zn0.2Ca alloy. The morphology and anti-corrosion property of the CaCO 3 protective coating are adjusted by the concentration of MgSO 4 in coating preparation electrolyte. The results reveal that the presence of MgSO 4 stabilizes the precipitation of metastable CaCO 3 crystalline (aragonite and vaterite) and affects the structure and growth rate of the middle calcite layer on Mg alloy surface, which leads to the transformation of cubic calcite into small rhombohedral aggregates in the middle layer as the concentration of MgSO 4 increases. Consequently, the corrosion protection property of the coating is significantly enhanced due to the increased compactness of the coating as the concentration of MgSO 4 increases from 0 mM to 20 mM. Whereas, with further increase of MgSO 4 concentration, the spindle-shaped calcite crystalline formed in the middle layer provides more penetrable boundaries, leading to a lower resistance for Mg substrate. Long-term immersion tests indicate the transformation of CaCO 3 into calcium phosphate, which exhibits a great prospect for Mg alloys as orthopedic implants. [ABSTRACT FROM AUTHOR]

Coal combustion in coal-fired power plants is one of the important anthropogenic NO x sources, especially in China. Many policies and methods aiming at reducing pollutants, such as increasing installed capacity and installing air pollution control devices (APCDs), especially selective catalytic reduction (SCR) units, could alter NO x emission characteristics (NO x concentration, NO 2 /NO x ratio, and NO x emission factor). This study reported the NO x characteristics of eight new coal-fired power-generating units with different boiler patterns, installed capacities, operating loads, and coal types. The results showed that larger units produced less NO x , and anthracite combustion generated more NO x than bitumite and lignite combustion. During formation, the NO x emission factors varied from 1.81 to 6.14 g/kg, much lower than those of older units at similar scales. This implies that NO x emissions of current and future units could be overestimated if they are based on outdated emission factors. In addition, APCDs, especially SCR, greatly decreased NO x emissions, but increased NO 2 /NO x ratios. Regardless, the NO 2 /NO x ratios were lower than 5%, in accordance with the guidelines and supporting the current method for calculating NO x emissions from coal-fired power plants that ignore NO 2 . [ABSTRACT FROM AUTHOR]

It was reported that Proprotein convertase subtilisin/kexin type 6 (PCSK6) can promote the progression of rheumatoid arthritis to a higher aggressive status. In this work, a novel visible light induced photoelectrochemical (PEC) platform was designed to detect PCSK6 gene. ZnO@CdTe nanocable arrays/carboxylated g-C 3 N 4 used as the PEC signal generator. Hexagonal ZnO nanorods grew on ITO electrode firstly. CdTe were then electrodeposited on the ZnO nanorods surface to enhance the photogenerated h + /e − separation efficiency. Carboxylated g-C 3 N 4 was utilized to improve h + /e − separation efficiency and anchor the capture probes of PCSK6 gene by the covalent bonding effect. The 5′ and 3′ primers captured PCSK6 ssDNA by the specific recognition. The linear range was 10 pg/mL to 20.0 ng/mL with a detection limit of 2 pg/mL. [ABSTRACT FROM AUTHOR]

• The surface recombination velocities of silicon wafers can be accurately determined due to the improved measurement sensitivity. • No independent measurement of the instrumental frequency response is required. • The proposed method can be further used to the quick and accurate characterization the surface passivation quality of silicon wafers. Surface recombination has a great impact on the performance of solar cells and photodetectors, and thus is necessary to be accurately determined. In this paper, a self-normalized photocarrier radiometry (PCR) with mean square variance graph is employed to improve the determination accuracy of the surface recombination velocities of silicon wafers and to reduce the influence of initial values on multi-parameter estimations. In this method data obtained from both the illuminated front surface and the illuminated rear surface are employed. The uncertainties of the estimated carrier recombination parameters, especially for the surface recombination velocities are improved significantly. Moreover, the influence of instrumental frequency response (IFR) on the multi-parameter estimation is totally eliminated. Theoretical simulations and experiments are performed to confirm the theoretical predictions. The estimated average uncertainties of the front and back surface recombination velocities for the sample used are approximately ± 7.60% and ± 5.71% by the proposed method, which are much improved than ± 13.65% and >±50% by the conventional method. [ABSTRACT FROM AUTHOR]

Highlights: [•] The OH-terminated MAO surface promoted the generation of TiO2 layer. [•] The interface was bonded by the interaction of phosphate radical and Ti–O bond. [•] The chemically anchored interface contributed to the in vitro degradation slowdown. [ABSTRACT FROM AUTHOR]

Abstract: Copper(II) catalyzed cross-dehydrogenative coupling of cyclic benzylic ethers with a variety of simple carbonyl compounds mediated by Na2S2O8 is developed. The scope of carbonyl components is broad, including simple aldehydes as well as ketones. The use of Na2S2O8 as the oxidant for the CDC reaction is attractive based on economical and environmental factors. [Copyright &y& Elsevier]

Highlights: [•] The addition of La in Cu-based oxides increased the types of active oxygen. [•] NO x adsorption, soot oxidation and simultaneous NO x -soot removal were enhanced. [•] The possible catalytic mechanism was studied via in situ FTIR analysis. [•] Soot oxidation was promoted by the NO2 intermediate. [ABSTRACT FROM AUTHOR]

Abstract: 〈001〉 textured Bi4Ti3O12 platelets with micro scale size were synthesized by a facile molten salt method. The photocatalytic activities of the as-prepared samples were measured with the photodegradation of methylene blue at room temperature under visible light irradiation. The Bi4Ti3O12 with the aspect ratio of 35 exhibited good absorption in the visible light region and the photodegradation against methylene blue was higher than that of anatase TiO2 reference, showing that the high degree of preferred {001} facets on the plate surface benefits the electronic transmission. In addition, the layer-pervoskite structure facilitates the mobility of the photogenerated carriers and hampers their recombination. The above results indicated that the large specific surface area of the as-prepared samples could attribute to the presence of a number of oxygen vacancies and then lead to the good photo-electric property. This work proposed an alternative way to tailor the structure of micro-sized platelets to get excellent properties comparable to the nano materials. [Copyright &y& Elsevier]

Abstract: Biodegradable magnesium alloys are potential for bone implants. In order to improve the corrosion resistance and the surface bioactivity of Mg–Zn–Ca alloy, a composite coating which had high adhesion strength with the substrate was prepared on Mg–Zn–Ca alloy through combined micro-arc oxidation and electrochemical deposition. The composite coating had needle-like structure and consisted of MgO, Mg3(PO4)2, hydroxyapatite and octacalcium phosphate. The thickness of the composite coating was about 12–15μm and the adhesion strength of the optimum composite coating with the substrate was higher than 40MPa. The potentiodynamic polarization and hydrogen evolution tests in simulated body fluid indicated that the composite coating significantly improved the corrosion resistance of the substrate. Deposition of Ca/P salt on the composite coating showed good surface bioactivity of the composite coating in hydrogen evolution tests. The compression tests of the composite coating modified alloy immersed in simulated body fluid for different time revealed that it could meet requirement of bone implant materials in the initial bone reunion period. Thus, the surface modification of the composite coating greatly enhanced the potential of magnesium and its alloy as degradable implants. [Copyright &y& Elsevier]

Abstract: A nano TiO2 film was coated on AZ31 alloy substrate by sol–gel method. The TiO2 film was characterized by X-ray diffractometry (XRD), differential scanning calorimetry-thermogravimetric analysis (DSC-TG), field emission scanning electron microscopy (FE-SEM) and energy dispersion spectroscopy (EDS). The degradation of the nano-TiO2 coated alloy was evaluated by immersion test and electrochemical measurement. An attempt was made to relate corrosion of coated alloys with the annealing treatment and resultant structural evolution. [Copyright &y& Elsevier]

Abstract: Magnesium alloys have been widely investigated in the field of biomaterials due to their moderate mechanical properties close to human bone and gradual degradation in human physiological environment without second surgeries. But results from clinical studies showed that magnesium implants suffered from too rapid degradation in human physiological environment. To reduce the degradation rate of magnesium alloys, surface modification is essential and effective besides element alloying. In this study, TiO2 films were deposited on Mg–Zn alloy by direct current reactive magnetron sputtering. The morphology and structure of the films were characterized by atomic force microscopy (AFM), scanning electron microscope (SEM) and X-ray diffraction (XRD). The corrosion resistance in simulated body fluid (SBF) at 37°C was evaluated by potentiodynamic polarization and hydrogen evolution tests. The corrosion behavior of the samples was investigated by SEM with energy dispersive spectroscopy (EDS) after immersion for different periods. The results showed that the compact films were composed of particles with the size of about 100nm and could effectively improve the corrosion resistance in SBF. After immersion for 10 days, the corrosion rates of the substrates and samples with TiO2 films were 4.13mm/y and 1.95mm/y, respectively. During the immersion, the TiO2 films could induce the growth of hydroxyapatite (HAp) to improve the bioactivity of the samples. [ABSTRACT FROM AUTHOR]

Abstract: The non-phosgene carbonylation of 1,6-hexamethylenediamine (HDA) with alkyl carbamates using Y(NO3)3·6H2O as a catalyst and the influence of reaction variables on the yields of dialkyl hexamethylenedicarbamate (HDC) were studied. At 453K and in the presence of 5wt.% Y(NO3)3·6H2O, nearly 100% HDA conversion and 85% dibutyl hexamethylenedicarbamate (BHDC) isolated yield could be achieved when butyl carbamate (BC) was employed as a carbonyl source. During reaction, an induction period was observed, but it almost disappeared by pretreating the catalyst with n-butanol. The FT-IR, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) characterizations of the catalyst showed that some transformation occurred when the catalyst was pretreated with n-butanol or employed during reaction, i.e., part decomposition of Y(NO3)3 to Y2O3, conversion from crystal to amorphous state, changes occurring in chemical state of the active species, as well as some subtle interactions between the catalyst and n-butanol. All these observed changes might be the reason resulting in activation of the catalyst. [Copyright &y& Elsevier]

• Three Schiff bases as new corrosion inhibitors for Mg alloy were synthesized. • The Schiff bases could effectively control the degradation rate of Mg alloy. • The inhibition mechanism is that Schiff bases complex with Mg2+ to form complexes. • Providing a new reference for the controlled degradation of bio-magnesium alloys. In this research, three new Schiff bases were synthesized by paeonol and amino acids and tested as corrosion inhibitors for Mg-Zn-Y-Nd alloy. Weight loss measurements and electrochemical measurements demonstrated that three Schiff bases showed high inhibition efficiency on Mg corrosion. The corrosion products on Mg surface were analyzed by scanning electron microscopy (SEM), Fourier transform infrared spectrum (FTIR) and X-ray photoelectron spectroscopy (XPS). The possible inhibition mechanism was proposed, in which the Schiff bases react with Mg2+ ions to form complexes on Mg surface in inhibitors-containing electrolytes. The theoretical calculation of quantum chemical demonstrated the experimental findings. [ABSTRACT FROM AUTHOR]

• Sulfate attack under three conditions. • Parts of bound chlorides will be released due to sulfate attack. • C b is more advantageous than R b for evaluating the chloride binding. • The influence of MgSO 4 attack on the stability of bound chlorides depends on the concentration of MgSO 4 solution. Chloride binding is an important factor for chloride transport in cementitious materials. The ions from the pore solution or the environment may affect the stability of the bound chlorides. In this study, the equilibrium method was used to investigate the stability of bound chlorides of well hydrated cement paste (HCP) with different concentrations of sodium sulfate (Na 2 SO 4) and magnesium sulfate (MgSO 4) attack under three conditions (including: I. HCP intermixed with chloride was submerged in sulfate solution; II. HCP was soaked in combined chloride-sulfate solution; III: HCP was exposed to chloride solution, followed by sulfate solution). Experimental techniques including X-ray diffraction (XRD) and thermogravimetric (TG) were combined to identify the phase assemblage of HCP before and after sulfate attack. The results show that the presence of sulfate decreases the amount of bound chlorides, which is mainly caused by the decomposition of Friedel's salt. Besides, the influence of MgSO 4 attack on the stability of bound chlorides depends on the concentration of MgSO 4 solution. As a result of the "blocking effect" of brucite, sample exposed to 1% MgSO 4 presented a higher chloride binding capacity than that exposed to 1% Na 2 SO 4 solution. However, extensive brucite and gypsum were formed with the increase of the concentration of MgSO 4 solution. This leads to the formation of microcracks in cement paste, which provides additional routes for the ingress of sulfate ions. [ABSTRACT FROM AUTHOR]

This study describes the preparation and characterisation of MIL-53(Fe) and its effect on the performance of forward osmosis (FO) membranes. The cellulose acetate (CA)/MIL-53(Fe) hybrid membranes were fabricated using the method of phase inversion by dispersing MIL-53(Fe) in a CA casting solution. To improve the selectivity and permeability performance of FO membranes, the effects of MIL-53(Fe) content, casting solution temperature, coagulation bath temperature, and annealing temperature were studied. Results from scanning electron microscopy, membrane porosity, atomic force microscopy, and water contact angle tests of all the membranes show that the structural properties of the CA/MIL-53(Fe) hybrid membranes were optimised. The results of the FO performance tests, including the values of water flux and reverse salt flux, indicate improvement in the selectivity and permeability properties of the CA/MIL-53(Fe) hybrid membranes. Under the conditions of deionised water as the feed solution and 1 M NaCl solution as the draw solution, the water flux and reverse salt flux of the CA/MIL-53(Fe) hybrid membranes reached 34.9 L/(m2·h) and 2.02 g/(m2·h), respectively, in comparison with CA membranes. This study demonstrates that MIL-53(Fe) can improve the desalination performance and structural properties of FO membranes. • MIL-53(Fe) with high porosity was used to fabricate cellulose acetate (CA)/MIL-53(Fe) hybrid membranes for the first time. • Optimal experimental conditions of CA/MIL-53(Fe) hybrid membranes were conducted. • The water flux and reverse salt flux of CA/MIL-53(Fe) hybrid membranes were improved compared to CA membranes. • Effect of MIL-53(Fe) on structural properties of CA membranes was widely discussed. [ABSTRACT FROM AUTHOR]