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Thermal regime evolution and settlement behavior of a riverbank over ice-rich permafrost in 20 years were estimated by numerical simulation and layerwise summation calculation. The results show that the permafrost under the riverbank will undergo a thawing process at a dramatically rate under the conditions of practical geology and construction structure, which is responsible for a remarkable settlement. The cases on different conditions of concrete hydration, backfilled soil temperature, seepage and mean annual ground temperature were also discussed, suggesting that these factors have the capability in improving the riverbank performance, among them seepage may be of the most importance. [ABSTRACT FROM AUTHOR]

In this article, we report on a controllable synthesis of superhydrophobic Sb 2 O 3 microcrystals via a solvothermal method assisted with the soluble inorganic Na 2 WO 4 salt. Morphologies of the final products depend on the amount of the OH − ions adsorbed on Sb 2 O 3 nanoplates. By varying the amount of NaOH, the octahedral Sb 2 O 3 can be switched to microcrystals or microspindles. Reaction and formation mechanisms of Sb 2 O 3 were also proposed, which may also benefit synthesis of other metal oxides with controllable morphology. Additionally, after modified by (Heptadecafluoro-1,1,2,2-tetradecyl) trimethoxysilane, the as-synthesized octahedral Sb 2 O 3 microcrystals and Sb 2 O 3 microspindles show superhydrophobic and excellent anticorrosion properties in acidic and basic circumstances. [ABSTRACT FROM AUTHOR]

Efficient removal of arsenic (As) and lead (Pb) from industrial wastewater has long been a critical environmental issue due to their serious risk to human health. Therefore, in this work, a modified banana peel biochar (MBPB) was prepared by mixing calcium nitrate, diammonium hydrogen phosphate, sulfuric acid, ferric nitrate with dehydrated banana peel biochar as adsorbent for As(V) and Pb(II) removal in wastewater, and their absorption mechanism was investigated. SEM-EDS, TEM, FTIR, XRD, XPS, BET, kinetic, and isothermal characteristics of MBPB and pristine banana peel biochar (PBPB) were conducted. The behavior of both metal ions on MBPB and PBPB was well explained by the pseudo-second-order kinetic with Langmuir and Freundlich models. We found that the two biochar's behaviors were mixture processes of monolayer and multilayer adsorption, achieving maximum capacities as determined by the Langmuir model of 39.5 mg g−1 (MBPB-As), 33.2 mg g−1 (MBPB-Pb), 30.8 mg g−1 (PBPB-Pb), and 23.5 mg g−1 (PBPB-As), with maximum efficiencies of 98.7% (MBPB-As) and 90.3% (MBPB-Pb) under optimum conditions. Thermodynamic tests showed that As(V) and Pb(II) removal on MBPB was a spontaneous and endothermic physisorption process. MBPB showed great reusability in As(V) and Pb(II) removal, with removal rates as high as 71.4% and 66.5% after five cycles, respectively. Selective adsorption of As(V) and Pb(II) was also investigated on MBPB, and the removal rate was still high in the mixture of heavy metals. These findings provide a feasible method for the environmental-benign utilization of banana peel as a low-priced adsorbent in wastewater treatment. [Display omitted] • Modified biochar made from banana peel for heavy metals removal was investigated. • Adsorbent was characterized by SEM-EDS, TEM, FTIR, XRD, and XPS techniques. • Modified biochar showed good adsorption performance for As(V) and Pb(II). • Adsorption mechanisms for As(V) and Pb(II) were defined. [ABSTRACT FROM AUTHOR]

• The local search algorithm based on K-Nearest Neighbor adaptively adjusts the K value in the natural neighbor searching process. • The search scheme improves the accuracy and efficiency for the natural element method. • The algorithm has high calculation accuracy in both the elastic analysis and large plastic deformation. Natural element method (NEM) is a meshless method based on the Voronoi diagram and Delaunay triangulation. It has the advantages of the meshless method, and simplifies the imposition of essential boundary conditions. NEM has great potential to solve the problems with large deformation. However, the high computational cost for searching natural neighbors is one of the main problems in NEM. In this paper a local algorithm based on K-Nearest Neighbor is presented for searching natural neighbors. Compared with the global sweep algorithm and other local search algorithms, the proposed algorithm introduces K to reduce the search scope. The value of K can be adjusted adaptively with the distribution characteristics of local neighbors of the calculation point and so the search can reach the global optimal value. The search scope changes with the flow of nodes, avoiding the problem that the natural neighbors exceed the search scope and reducing the calculation error. The proposed approach realizes the meshless characteristic in the natural neighbor searching process. The approach was used to solve the elastic deformation of a cantilever beam and a porous structure and the large plastic deformation in metal forming process. The results show that the proposed approach has great significance to solve problems in the elastic-plastic large deformation of metals and it is efficient. [ABSTRACT FROM AUTHOR]

The idea of employing slant grooves to achieve the conversion between the longitudinal vibration and the torsional vibration has been proposed for many years, however, comparative studies on the effectiveness of different forms of diagonal grooves are seldom reported. In this paper, a sandwich longitudinal-torsional (L&T) composite ultrasonic vibrator driven by a longitudinally polarized PZT stack is presented. Four diagonal grooves were equally distributed around the front mass of the vibrator for mode conversion purpose. The grooves can be machined either along thread curves or along straight lines. The influences of the thread grooves on the characteristics of the vibrator were compared with that of the straight grooves both numerically and experimentally. Modal, harmonic and transient analysis were conducted using a finite element model established in a commercial FEM software. Then, prototypes of a transducer and a pair of front mass with thread and straight grooves were manufactured for experimental purpose. The measurement results coincide with the FE simulation prediction. It indicates that although both types of grooves are able to convert the longitudinal vibration into L&T composite vibration, the thread grooves can achieve much larger torsional amplitudes. The present work provides useful information for engineers to make trade-offs between the two sorts of grooves at designing stage. [ABSTRACT FROM AUTHOR]

Titanium-zirconium-molybdenum (TZM) alloy was fabricated by using powder metallurgy and rolling techniques. Electrochemical corrosion behavior of the alloy was studied quantitatively using potentiodynamic polarization and scanning electron microscope. Effect of different chloride ions concentrations on corrosion resistance and electrochemical corrosion mechanism on TZM alloy was investigated. Results show that pitting corrosion and intergranular corrosion of TZM alloy mainly occurs in sodium chloride solution. Corrosion generates firstly in the form of pitting corrosion around second phase particles and increases with corrosive media Cl − concentration increasing, and then the intergranular corrosion occurs along grain boundaries and defects. Cl − corrosion can effectively destroy the passive film formed on the sample surface. As the Cl − concentration of corrosive media increases, the corrosion rate of TZM alloy increases until 1.0 mol/L and then decreases. TZM alloy exhibits good corrosion resistance when the concentration of Cl − in corrosive media is 0.5 mol/L or 1.5 mol/L. [ABSTRACT FROM AUTHOR]

Electrochemical corrosion behavior of platinum coated (Pt-coated) lanthanum doped titanium-zirconium-molybdenum alloy (La-TZM alloy) was studied in this paper. La-TZM alloy plates were fabricated using powder metallurgy and rolling technique, and platinum was coated on their surfaces by using electroplating. Corrosion behavior of Pt-coated La-TZM alloy samples were investigated in neutral and alkaline medium while the Cl − concentrations keep invariant, which was quantitatively analyzed using potentiodynamic polarization, scanning electron microscope and energy spectrum techniques. Results show that the Pt-coating can improve the corrosion resistance of the La-TZM alloy. Pt-coating on La-TZM alloy can effectively hinder the matrix alloy electrochemical corrosion during different corrosion mediums. In addition, the Pt-coating on La-TZM alloy in a neutral medium is more corrosion resistant than that in an alkaline medium. Pt-coating can effectively hinder the Cl − destroys the corrosion formed on the surface passivation film, OH − and Cl − double erosion promoted La-TZM alloy intergranular corrosion increased during the electrochemical corrosion processes. [ABSTRACT FROM AUTHOR]

The influence of crystalline memory effect on poly(lactic acid) (PLA) crystallization was probed by time-resolved Fourier transform infrared spectroscopy (FTIR). The melt with different degrees of order was prepared by melting at various temperatures. The vibrational changes associated with inter- and intra-chain interactions during crystallization were monitored. In the initial period of crystallization, the order of intensity changes is as follows: 1458 cm −1 > 1210 cm −1 ≫ 921 cm −1 , 1458 cm −1 > 1210 cm −1 > 921 cm −1 , and 1458 cm −1 > 1210 cm −1 ∼ 921 cm −1 for PLA melted at 190, 170, and 168 °C, respectively. With increasing the degree of order, both the formation of skeletal conformational-ordered structure and, especially, the 10 3 helix structure are accelerated. The influence of memory effect on the crystallization kinetics was also discussed based on the Avrami model. [ABSTRACT FROM AUTHOR]

Molybdenum powders were high-energy ball milled for 3, 6, 9 and 12 h respectively, using two ball milling methods: (1) dry milled in vacuum and (2) wet milled in mixed solution of ethanol-polyethylene glycol. The effect of high-energy ball milling on relative density of titanium-zirconium-molybdenum (TZM) alloy was investigated. Particle size distribution and calculated proportion in each size range were designed according to the Dinger-Funk model, reaching the dense packing state. The effects of three different kinds of carbon source (graphite, stearic acid (C 18 H 36 O 2 ) and carbon nanotubes (CNTs)) on oxygen content and relative density were analyzed. The effects of carbon source on oxygen content were studied. After high-energy milling, fine molybdenum alloy powder particles and large amounts of dislocations and vacancies are helpful to improve TZM alloy density during solid sintering process. Doping carbon nanotubes (CNTs) into the TZM alloy as carbon source can improve its density and decrease oxygen content, which is more effective than graphite or stearic acid as carbon sources. Higher TZM alloy relative density results in lower oxygen content. [ABSTRACT FROM AUTHOR]

Titanium-Zirconium-Molybdenum alloy and Lanthanum-doped Titanium-Zirconium-Molybdenum alloy were fabricated by powder metallurgy method. The effect of lanthanum in arc erosion of titanium-zirconium-molybdenum alloy was investigated by using SEM, arc erosion test system and analytical balance. Results show that lanthanum-doped Titanium-Zirconium-Molybdenum alloy has a higher strength, density and lower electrical resistivity compared to that of Titanium-Zirconium-Molybdenum alloy. The average of arc energy and the arc time decrease 17.9% and 20.9% respectively because doping lanthanum decreases the arc current by forming reverse current between the contacts. The mass loss decreases 32.5% and erosion area reduces 32.6%. The lanthanum in the cathode has a good ability of electron emission. [ABSTRACT FROM AUTHOR]

This study aimed to develop an exact mass suspect screening approach to perform finding of multiple lipophilic marine toxins (LMTs) in seawater, suspended particulate matter (SPM), and marine sediment from marine aquaculture area using liquid chromatography-time of flight mass spectrometry (LC-TOF/MS). The method was validated and proven to be reliable for the screening of various LMTs. Then, the method was applied to screen LMTs in marine environmental samples collected from mariculture area of Jiaozhou Bay, China. Okadaic acid (OA), pectenotoxin 2 (PTX2), etc were detected and tentatively identified. Positive detection results were confirmed by liquid chromatography-tandem mass spectrometry (LC–MS/MS), and contents of OA and PTX2 in seawater, SPM and marine sediment were also quantified. The mean concentration of OA ranged from 2.71 to 14.06 ng L −1 in seawater and from 0.78 to 3.34 ng g −1 dry weight in marine sediment. The mean concentration of PTX2 ranged from 0.86 to 7.90 ng L −1 in seawater, from 1.56 to 10.67 ng in SPM obtained from 1 L seawater sample and from 0.95 to 2.23 ng g −1 dry weight in marine sediment. The above results suggested that the proposed method was convenient and reliable for the screening of LMTs in different marine environmental samples. In addition, typical LMTs exist in different marine environmental media of the mariculture area of Jiaozhou Bay, China. Follow-up studies should focus on improving current understanding on the environmental behavior of these LMTs in the marine aquaculture environment. [ABSTRACT FROM AUTHOR]

Background There is good evidence that air pollution is a risk factor for adverse respiratory and vascular health outcomes. However, data are limited as to whether ambient fine particles contribute to the transmission of influenza and if so, how the association is modified by weather conditions. Objectives We examined the relationship between ambient PM 2.5 and influenza incidence at the national level in China and explored the associations at different temperatures. Methods Daily data on concentrations of particulate matter with aerodynamic diameter < 2.5 μm (PM 2.5 ) and influenza incidence counts were collected in 47 Chinese cities. A Poisson regression model was used to estimate the city-specific PM 2.5 -influenza association, after controlling for potential confounders. Then, a random-effect meta-analysis was used to pool the effects at national level. In addition, stratified analyses were performed to examine modification effects of ambient temperature. Results For single lag models, the highest effect of ambient PM 2.5 on influenza incidence appeared at lag day 2, with relative risk (RR) of 1.015 (95% confidence interval (CI): 1.004, 1.025) associated with a 10 μg/m 3 increase in PM 2.5 . For moving average lag models, the significant association was found at lag 2–3 days, with RR of 1.020 (95% CI: 1.006, 1.034). The RR of influenza transmission associated with PM 2.5 was higher for cold compared with hot days. Overall, 10.7% of incident influenza cases may result from exposure to ambient PM 2.5 . Conclusions Ambient PM 2.5 may increase the risk of exposure to influenza in China especially on cooler days. Control measures to reduce PM 2.5 concentrations could potentially also be of benefit in lowering the risk of exposure and subsequent transmission of influenza in China. [ABSTRACT FROM AUTHOR]

Pt coating on La-TZM alloys can effectively hinder the matrix alloy oxygen corrosion during high temperature oxidation processes. Doping powder metallurgy was used to prepare La-TZM alloy plates (doped with lanthanum), and electroplating was utilized to deposit a platinum coating on the plate surface. After high temperature treatment of the Pt-coated La-TZM alloy samples at different times and temperatures, scanning electron microscopy and energy dispersive spectra analysis of the sample surface and cross-sections were performed to observe the microstructure and composition changes. Differential thermal analysis of the Pt-coated La-TZM alloy specimens after high temperature treatment was performed to assess the high temperature oxidation resistance of the coated matrix alloy. The results show that the oxidation resistance of the TZM alloy can be enhanced, expanding its temperature application range. [ABSTRACT FROM AUTHOR]

La-doping titanium-zirconium-molybdenum alloys have good arc erosion resistance performances, but there is no research about the changes during the arc erosion. Arc erosion characteristics of La-doping titanium-zirconium-molybdenum alloys after 5000 operations under direct current 20 V, 15 A and resistive load conditions were investigated using a JF04C test system. The results indicated that the probability distribution and change trend of arc energy and arc time during 5000 operations were similar and the relationship between arc time and arc energy followed exponential function. The change of arc energy with test number was consistent to electrical resistance. Oxide particles, crater and cracks defects were discovered on the surface of La-doping titanium-zirconium-molybdenum alloy. The electrical resistance change is mainly concerned with the surface. [ABSTRACT FROM AUTHOR]

The BiOI/BiOCl composites with high photocatalyitic and adsorption ablities were prepared via a facile ionic liquid assisted ultrasonic method in several hours at room temperature. The BiOI/BiOCl composites with different contents of BiOI can be conveniently synthesized via changing the amount of 1-ethyl-3-methylimidazolium iodide precursor during the preparation process. Microstructures, morphologies, porosities and bandgaps of the as-prepared samples were determined through various experimental methods. A first-principles calculation was employed to explicate electronic structures of the complex. Photocatalytic results suggest that the obtained BiOI/BiOCl composite with 40% BiOI has the highest photoactivity for the degradation of rhodamine-B and quinoline blue under visible light irradiation. All the rhodamine-B and quinoline blue can be degraded in 25 min and 15 min, respectively. To observe the universality of the BiOI/BiOCl, the degradation results of colorless target pollutant (tetracycline) was also investigated. Based on experimental and computational results, origins of the photocatalytic abilities leading to the observed results were proposed. [ABSTRACT FROM AUTHOR]

Unique structural and electric properties of inorganic layered crystals (ILCs) have enlarged their functions as hosting matrixes in material manipulations. While most doping routes were carried out via introducing hetero dopants into the ILC compounds, doping with their component elements or element clusters is scarcely reported. Here, we demonstrated a first-principles investigation of the ILC MoS 2 monolayer decorated with deficient and excessive Mo n and S n ( n = −3 → 3) clusters on 5 × 5 supercells, with more emphasis on the n > 0 cases. The X n @MoS 2 (X = Mo or S, n = −3 → 3) systems can keep intrinsic monolayer form. When n > 0, most X n clusters prefer to be adsorbed on the host. However, the Mo n ( n = 2, 3) clusters will extrude one S atom from the host, forming new SMo 2 and SMo 3 clusters above the slab. System magnetism was inherited from cluster dopants, and the Mo 1 @MoS 2 and Mo 3 @MoS 2 possess 3 μB. All bandgaps in the defective complexes are lower than the pristine host, with a transition from direct to an indirect bandgap in Mo n @MoS 2 ( n = −3, −1, 3) and in S n @MoS 2 ( n = −3, −2 −1). The Mo n @MoS 2 ( n > 0) systems are stable at room temperature according to molecular dynamic simulations. Combining the 0D isoelement clusters to the 2D layered hosts, the present work offers a possible manipulation strategy to boost semiconductive ILCs applications in magnetics without needs of introducing hetero impurities. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrostatic LBL self-assembly strategy is firstly employed to integrate MoS 2 with CMOF. • Superior rejection rates are increased above 27–55% more than that of monomer membranes for FQs. • Synergy of size exclusion, electrostatic repulsion, and hydrophilic interaction is explained. • High stability in harsh environments for 72 h and over 90% rejection against FQs in the real sample. Developing a novel nanofiltration membrane for effectively purifying antibiotic wastewater has been a daunting challenge in recent years. However, a convenient and controllable strategy for constructing membranes with two-dimensional nanomaterials (2DNMs) and metal–organic frameworks (MOFs) needs to be further studied. Herein, a loosely hierarchical architecture composite membrane has been fabricated, utilizing an electrostatic layer-by-layer (LBL) self-assembly method to intercalate chitosan crosslinked UiO-66-NH 2 MOFs (CMOF) into MoS 2 laminates. Through regulating the CMOF content, lower hydraulic-resisted channels and precise separation regions have been formed in the hierarchical architecture. The well-designed MoS 2 /CMOF composite membrane exhibited enhanced water permeance (78.98 ± 1.45 L·m-2h−1 bar−1) and superior antibiotic rejection capability (98.01 ± 1.12% for ciprofloxacin and 94.31 ± 0.68% for ofloxacin), which are increased by 27–55% more than monomer membranes. Detailed analysis results indicate the nanofiltration performance of the MoS 2 /CMOF composite membrane depends heavily on the synergistic mechanism, including the molecular sieving effect (size exclusion), electrostatic repulsion, and hydrophilic-hydrophobic interaction. Besides, the MoS 2 /CMOF composite membrane has emerged with excellent antifouling ability and long-term stability, which could maintain favorable rejection efficiency in continuous nanofiltration for 72 h under an alkaline and acidic environment. Furthermore, it presents over 90% antibiotic rejection rates for real water samples obtained from the municipal domestic sewage and livestock wastewater along the Xiangjiang River in China, indicating its good availability. In general, this work provides a new vision and a reasonable design strategy to construct 2DNMs/MOFs-based nanofiltration membranes with hierarchical architecture, further expanding their application in wastewater treatment and reclamation, in harmony with the global trend of green and low-carbon development. [ABSTRACT FROM AUTHOR]

The construction of advanced systems that can accurately detect neuron-specific enolase (NSE) is critical to the rapid diagnosis of small cell lung cancer (SCLC). Herein, a luminol-based electrochemiluminescence (ECL) biosensor enhanced by reactive oxygen species (ROS) is proposed to perform the ultrasensitive detection of NSE. D-Fe 2 O 3 @Pt, synthesized as a signal indicator, was combined with luminol to significantly shorten its electron transfer pathway. Its peroxidase activity catalyzed the decomposition of H 2 O 2 to generate a large amount of •OH, thus considerably increasing the ECL signal of the luminol–H 2 O 2 system. CePO 4 /CeO 2 heterostructures with improved surface-active areas were then employed as sensing substrates. The platform enabled the accelerated generation of O 2 •− through enriched Ce4+/Ce3+ redox pairs, thereby amplifying the strength of the response of the foundation. Through integrated dual ROS amplification, the proposed sandwich ECL immunosensor configuration achieved sensitive detection in the detection range of 76 fg/mL – 100 ng/mL, with a detection limit of 72.4 fg/mL. Furthermore, the sensor exhibited high selectivity for the determination of NSE in human serum. Overall, this study serves as an important reference for integrating ROS and enzymatic strategies in ECL research to achieve accurate, sensitive, and highly selective detection of a target. [ABSTRACT FROM AUTHOR]

To improve and adjust the combustion and energy output of HMX/Al, graphite fluoride (CF) as oxidizer was introduced in HMX/Al and gradient structured HMX/Al/CF was prepared by additive manufacturing technology. For HMX/Al added with CF, a significantly exothermic peak is observed ranging from 860 to 950 °C due to the reaction of Al and fluorine derived from CF decomposition, and the heat release increases by 106.63% compared to that of HMX/Al. The fourth exothermic heat increases from 161.48 to 955.25 J/g with the increased Al content from 10 to 30 wt%. Moreover, the combustion rate and pressure output of HMX/Al have been improved by introducing CF. For HMX/Al added with CF, the combustion time decreases from 10.3 to 2.5 s, which is dependent on the Al content from 10 to 30 wt%. And the highest peak pressure is 1712.2 kPa when Al content is 20 wt% in HMX/Al/CF composites. Furthermore, gradient structured HMX/Al/CF consisting of three layers with Al content of 10, 20 and 30 wt% was prepared to improve combustion and pressure output. The combustion rate and peak pressure of gradient structured HMX/Al/CF are higher than those of single structured HMX/Al/CF. The highest peak pressure (∼2.24 MPa) is obtained when the Al content of the middle layer and outer layer is 30 wt% and 20 wt% in the gradient structured HMX/Al/CF cylinder, respectively. Finally, the reaction intermediates and combustion reaction products were fully characterized to understand the enhanced effect of CF in HMX/Al. This work provides a promoting way to improve and regulate the combustion reaction performance and pressure output of HMX/Al. [ABSTRACT FROM AUTHOR]

• Unveiling the role of carbonate in Ni-based core/shell plasmonic photocatalyst. • Revealing amorphous NiCO 3 as an active side for H 2 reduction via DFT calculations. • Enhancing photocatalytic activity by the incorporation of NiO as a middle layer. • Optimizing the photocatalytic performance by post-vacuum annealing thermal treatment. Though carbonates are known for several decades, their role in sun-light driven photocatalysis is still hidden. Herein, carbonate boosted solar water splitting in nickel-based plasmonic hybrid nanostructures is disclosed for the first time via in-situ experiments and density-functional theory (DFT)-based calculations. Ni@NiO/NiCO 3 core@shell (shell consisting of crystalline NiO and amorphous NiCO 3) nanostructure with varying size and compositions are studied for hydrogen production. The visible light absorption at ∼470 nm excludes the possibility of NiO as an active photocatalyst, emphasizing plasmon driven H 2 evolution. Under white light irradiation, higher hydrogen yield of ∼80 µmol/g/h for vacuum annealed sample over pristine (∼50 µmol/g/h) complements the spectroscopic data and DFT results, uncovering amorphous NiCO 3 as an active site for H 2 absorption due to its unique electronic structure. This conclusion also supports the time-resolved photoluminescence results, indicating that the plasmonic electrons originating from Ni are transferred to NiCO 3 via NiO. The H 2 evolution rate can further be enhanced and tuned by the incorporation of NiO between Ni and NiCO 3. [ABSTRACT FROM AUTHOR]

The salinity of soil can result in serious potential environmental hazards such as increased collapsibility and corrosiveness. Microbially induced carbonate precipitation is an upcoming and pollution-free treatment modality that can eliminate environmental and engineering hazards of saline soil. To verify the feasibility of the method of curing saline soils, a series of tests were conducted to investigate the impact of chloride salt on urea hydrolysis, the impact of the method on engineering and mechanical properties of coarse-grained soils containing chloride salt and the deterioration mechanism of curing effect caused by salt. The study demonstrated that, even though the curing effect of the method is excellent, the negative effect of salt cannot be ignored. With increased salt concentration, the hydrolysis rate and calcium carbonate precipitation efficiency sharply decrease at first and tend to be flatter. The unconfined compressive strength and shear strength of the samples can be greatly improved through the application of the method. However, calcium carbonate content reduces with an increase in the salt content, which decreases the strength. Compared to uncured samples, the permeability coefficient of cured samples reduced from 1 to 2 orders of magnitude. On the other hand, as the dominant aperture size increases with a decrease in the calcium carbonate content, the permeability coefficient increases with an increase in the salt content. Furthermore, micro-mechanical tests, such as X-ray diffraction and scanning electron microscope tests, were conducted to analyze the mechanism by which salt degrades the reinforcement. As a guiding agent, while chloride salt can improve the proportion of calcite in calcium carbonate, it decreases the total quantity of calcium carbonate through the limiting urea hydrolysis process. A significant amount of calcium carbonate is deposited on the surface of the particles in each sample, especially the contact surface. In conclusion, even though salt has a certain deterioration effect, microbially-induced carbonate precipitation is still an effective and environment-friendly method to cure saline soil. This study can provide a theoretical basis for using this method to solidify saline soil. [ABSTRACT FROM AUTHOR]

Ionic liquid assisted ultrasonic method was developed to prepare BiOCl at room temperature in a short time. Through this method, BiOCl with different controllable morphologies can be easily obtained via the simple change of the reaction solvents. The flowerlike microspheres, sheet and plate morphologies have been prepared in DMF, ethanol and water, respectively. And the as-prepared BiOCl samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), N 2 absorption-desorption isotherms and UV–vis diffuse reflectance spectroscopy. The photocatalytic activity of the as-prepared samples was evaluated towards degradation of Rhodomine B (RhB), Quinoline blue (QB) and methyl orange (MO). The results indicate that the as-prepared BiOCl samples have high photoactivities for the degradation of dyes both under the visible light irradiation and sunlight irradiation. [ABSTRACT FROM AUTHOR]

Nanoporous cobalt (NPCo) with three-dimensional network nanostructure was obtained by selectively dealloying Al from CoAl alloy in a mild alkaline solution. Co 3 O 4 grew further on the surface of NPCo and then NPCo/Co 3 O 4 was obtained. Gold nanoparticles functionalized NPCo/Co 3 O 4 (NPCo/Co 3 O 4 –Au) was used to fabricate electrochemiluminescence (ECL) modified electrodes for detecting mycotoxin deoxynivalenol (DON). In addition the introduction of AuNPs enhanced the conductivity, and NPCo/Co 3 O 4 –Au exhibited excellent catalytic properties for the luminescence of RuSi@Ru(bpy) 3 2+ . The fabricated ECL modified electrodes exhibited a high activity for DON in a wide linear range from 5 pg/mL to 100 ng/mL with a low detection limit of 1 pg/mL. The NPCo/Co 3 O 4 –Au based ECL modified electrodes displayed excellent stability and reproducibility, and successfully achieved the detection of DON in wheat flour with desirable results as well. The NPCo/Co 3 O 4 –Au possesses great application potential for ECL modified electrodes with sample detection, unique catalytic activity, and high structure stability. [ABSTRACT FROM AUTHOR]

Uniaxial deformation of amorphous poly(lactic acid) (PLA) film was performed at 60 °C (around the glass transition temperature). The deformed samples revealed a strain-induced mesophase, and its fraction and thermal stability increased with draw strain. Further annealing was performed in situ at constant length, at the drawing temperature for the films drawn to strains of 100% and 230%. Interestingly, the orientation of amorphous phase relaxed more rapidly for the 100% sample compared with the 230% one. This could be ascribed to the constraint effect of mesophase on the amorphous chains. In addition, the chains of mesophase relaxed slightly for the 100% sample while it retained high orientation for the 230% sample. Meanwhile, the mesophase fraction decreased, and the trend was more significant for the sample drawn to 100%. These effects can be ascribed to the melting of mesophase and the different thermal stabilities of the mesophases. [ABSTRACT FROM AUTHOR]

A novel and simple photoelectrochemical (PEC) bioassay protocol for estradiol was proposed based on in situ generated CdS-enhanced TiO 2 film via competitive strategy. The CdS was generated in situ by immediately dropping S 2− onto the Cd 2+ -functionalized titanium phosphate nanoparticles (TiP@Cd 2+ ). The TiO 2 photoactive sensing film with countless active sites was obtained by calcination and further explored for estradiol (E 2 ) capture. The TiP@Cd 2+ was used as labels and immobilized through affinity-specific binding with E 2 on the surface of the electrode. Greatly enhanced sensitivity was achieved by using porous TiP nanoparticles as carriers to load a large amount of Cd 2+ and further for more CdS production through the S 2− deposition. What's more, the photocurrent of CdS generated on the electrode surface could be significantly amplified by the coupling of CdS and TiO 2 , which could enhance the excitation and photo-to-electric conversion efficiency. Through the application of a competitive binding assay, the proposed biosensor showed high sensitivity with a detection limit down to 2 pg/mL. This simple and fast PEC E 2 -sensing approach offers great promise to extend its application for the assay of small molecules of biomedical, food and environmental interest. Additionally, the strategy of employing in situ generated narrow-band gap semiconductors paves a new way for PEC sensing. [ABSTRACT FROM AUTHOR]

The effects of drawing temperature ( T d ) and draw strain on the orientation and structure of semicrystalline poly(lactic acid) (PLA) films were investigated by wide angle X-ray diffraction and polarized Fourier transform infrared spectroscopy. Semicrystalline PLA samples with two initial levels of crystallinity, X c = 1% and 11%, were prepared by cold crystallization at 80 ° C. Whatever X c and T d , the total amount of the ordered phases ( i.e. crystalline + mesophase) increased with draw strain, which could be ascribed to the formation of strain-induced mesophase at T d = 60 or 70 ° C but crystalline at 80 ° C. Also, the molecular orientation of both the amorphous and ordered phases increased with draw strain. Whatever X c , the orientation of the ordered phases was insensitive to T d , whereas higher orientation in the amorphous phase was achieved at lower T d , and the trend was more significant for X c = 1% compared with 11%. [ABSTRACT FROM AUTHOR]

A novel non-enzymatic immunoassay was designed for ultrasensitive electrochemical detection of carcino-embryonic antigen (CEA) using β-cyclodextrin functionalized Cu@Ag (Cu@Ag-CD) core–shell nanoparticles as labels and β-cyclodextrin functionalized graphene nanosheet (CD-GN) as sensor platform. CD-GN has excellent conductivity which promoted the electric transmission between base solution and electrode surface and enhanced sensitivity of immunosensor. In addition, owing to supramolecular recognition of CD-GN for the guest molecule, quite a few synthesized adamantine-modified primary antibodies (ADA-Ab 1 ) were immobilized on the CD-GN by supramolecular host–guest interaction between CD and ADA. Cu@Ag-CD as a signal tag could be captured by ADA-modified secondary antibody (ADA-Ab 2 ) through a host–guest interaction, leading to a large loading of Cu@Ag nanoparticles with high electrical conductivity and catalytic activity. The fabricated immunosensor exhibits excellent analytical performance for the measurement of CEA with wide range linear (0.0001–20 ng/mL), low detection limit (20 fg/mL), good sensitivity, reproducibility and stability, which provide an enormous application prospect in clinical diagnostics. [ABSTRACT FROM AUTHOR]

Abstract: Constructions of versatile electroactive labels are key issues in the development of electrochemical immunosensors. In this study, copper-doped titanium dioxide nanoparticle (Cu@TiO2) was synthesized and used as labels for fabrication of sandwich-type electrochemical immunosensors on glassy carbon electrode (GCE). Due to the presence of copper ions, Cu@TiO2 shows a strong response current when coupled to an electrode. The prepared nanocomposite also shows high electrocatalytic activity towards reduction of hydrogen peroxide (H2O2). The dual functionality of Cu@TiO2 enables the fabrication of immunosensor using different detection modes, that is, square wave voltammetry (SWV) or chronoamperometry (CA). While Cu@TiO2 was used as labels of secondary antibodies (Ab2), carboxyl functionalized graphene oxide (CFGO) was used as electrode materials to immobilize primary antibodies (Ab1). Using human immunoglobulin G (IgG) as a model analyte, the immunosensor shows high sensitivity, acceptable stability and good reproducibility for both detection modes. Under optimal conditions, a linear range from 0.1pg/mL to 100ng/mL with a detection limit of 0.052pg/mL was obtained for SWV analysis. For CA analysis, a wider linear range from 0.01pg/mL to 100ng/mL and a lower detection limit of 0.0043pg/mL were obtained. The proposed metal ion-based enzyme-free and noble metal-free immunosensor may have promising applications in clinical diagnoses and many other fields. [Copyright &y& Elsevier]

[Display omitted] • Slightly crosslinked PVDF is prepared by γ-ray irradiation. • Piezoelectric film is fabricated by melt stretching of slightly crosslinked PVDF. • The film shows high optical transmittance and also superior mechanical properties. • Ultrahigh content of electroactive β-phase is obtained with aligned nanofibrils morphology. • Excellent sensing performances of film are demonstrated by serving as a wearable sensor. Flexible, transparent and lightweight polymer piezoelectric films are promising for emerging sensor applications, including wearable electronics and human–machine interfaces. However, it remains a great challenge for large-scale fabrication of high-quality polymer piezoelectric films by a cost-effective melt processing approach, mainly due to the difficulty of acquiring well-defined electroactive phases. Herein, a readily implementable and scalable strategy is reported to achieve poly(vinylidene fluoride) (PVDF) film with ultrahigh content of electroactive β-phase (∼96%) via melt stretching of slightly crosslinked PVDF. Upon controlled temperature and stretch ratio, the β-phase adopts an oriented nanofibril (diameter, 21.6 nm) morphology, while nanofibrils are further densely and parallelly aligned to fill the film space. The hierarchical nanoscale phase morphology endows the slightly crosslinked film with high optical transmittance (∼90%), good flexibility and also superior mechanical properties. Moreover, flexible piezoelectric device constructed on the film is demonstrated to have excellent electrical output with sensitive and repeatable responses in sensing dynamic pressure (0–250 kPa), temperature variation (3.3 mV oC-1), human motions and subtle physiological activities. This study therefore paves the way towards scalable manufacturing of high-performance piezoelectric polymer film through simple melt stretching. [ABSTRACT FROM AUTHOR]

Compared to polymer fibers, it is still challenging for fabricating large-scale polymer products with superb mechanical properties. Herein, high density polyethylene (HDPE) films reinforced with carbon nanotubes (CNTs) were prepared via an ingenious high-speed melt stretching strategy. With employing a homemade two-drum extensional rheometer, the maximum 80 × stretch ratio of supercooled melt was realized within very short time of 220 ms. The achieved nanocomposite films present the highest tensile strength of 147 MPa in reported HDPE-based composites, while the Young's modulus keeps simultaneously a high level of 2300 MPa in spite of low filler fraction of 3 wt%. Furthermore, the nanocomposite films display an excellent erosion resistance, ensuring the durability in harsh using environments. Microstructural characterization indicates a strong synergy between high-speed melt stretching and CNTs in (1) forming the densely distributed shish-kebab superstructures, (2) making a nearly perfect orientation of shish-kebab crystal and (3) reinforcing the physical connectivity of shish-kebab network. The construction of such characteristic microstructures greatly improves the transfer of mechanical load and underlies a significant enhancement on the mechanical performance. Due to the ultrastrong nanocomposite films fabricated directly by melt processing, the current work is of guiding significance in engineering practice and lights a feasible path towards expanding applications of general plastics to some special occasions like collision protection and structural materials. [Display omitted] • PE/C nanocomposite films are fabricated by high-speed melt stretching. • Films show ultrahigh mechanical properties and excellent erosion resistance. • Dense shish-kebab superstructures with nearly perfect orientation are formed. • CNTs greatly reinforce physical connectivity of shish-kebab crystal network. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Li-TFSI was encapsulated in the NH 2 -MIL-101, preventing from attack of water. • The regular oxidation process of doped devices can be performed in an ambient condition. • Amino functionalized Li-TFSI@NH 2 -MIL-101 could inhibit the ion migration of Pb2+. • This approach realizes an enhanced stability for 10-fold that of conventional devices. Lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) is generally regarded as a conventional p-dopant for classical hole transport material Spiro-OMeTAD, which improves the hole mobility and conductivity of hole-transporting layer (HTL). However, the hygroscopic Li-TFSI would absorb moisture and accelerate the degradation of perovskite film, causing a decline in the long-term stability of perovskite solar cells (PSCs). Herein, a novel dopant Li-TFSI endohedral metal–organic frameworks (namely Li-TFSI@NH 2 -MIL-101) is constructed for reducing the amount of Li salt and resisting the attack from water molecules. With a significantly decreased Li salt loading mass, the optimal power conversion efficiency (PCE) of 19.01% is achieved for Li-TFSI@ NH 2 -MIL-101 doped PSCs, which is comparable to that of conventional devices (19.23%). Furthermore, the strong interaction between ammonium groups (–NH 2) and uncoordinated Pb2+ ions would passivate the trap states and inhibit ion migration at perovskite/hole transport layer interface, which further improve the device stability. Importantly, this approach realizes an enhanced stability for approximately 10-fold that of conventional devices at the preliminary stage (time to reduce to 90% of initial PCE). The Li-TFSI@NH 2 -MIL-101 doped PSCs display impressive property stability retaining over 85% of the optimal PCE after 3600 h storage in ambient environment (room temperature and RH ≈ 40%). [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple method is presented using different DMSO/salt mixtures to optimize TE PEDOT:PSS films. • Seebeck coefficients and conductivities provide optimized power factors. • The morphology-structure–property relationship of the TE systems is gained. The combination of dimethyl sulfoxide (DMSO)-solvent doping and physical–chemical DMSO/salt de-doping in a sequence has been used to improve the thermoelectric (TE) properties of poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) films. A high power factor of ca. 105.2 µW m−1 K−2 has been achieved for the PEDOT:PSS film after post-treatment with 10 % sodium sulfite (Na 2 SO 3) in the DMSO/salt mixture (v/v), outperforming sodium bicarbonate (NaHCO 3). The initial DMSO-doping treatment induces a distinct phase separation by facilitating the aggregation of the PEDOT molecules. At the same time, the subsequent DMSO/salt de-doping post-treatment strengthens the selective removal of the surplus non-conductive PSS chains. Substantial alterations in the oxidation level, chain conformations, PEDOT crystallites and their preferential orientation are observed upon treatment on the molecular level. At the mesoscale level, the purification and densification of PEDOT-rich domains enable the realization of inter-grain coupling by the formation of the electronically well-percolated network. Thereby, both electrical conductivity and Seebeck coefficient are optimized. [ABSTRACT FROM AUTHOR]

Abstract: The effect of one of the 1,3,5-benzenetrisamide derivatives, N,N',N''-tricyclohexyl-1,3,5- benzenetricarboxylamide (defined here as TMC), on the crystallization behavior of isotactic polypropylene (iPP) was investigated by differential scanning calorimetry. TMC shows excellent nucleating effect on iPP. The nucleation efficiency of the blends reaches 30% even at a very low loading of 0.05 wt% TMC. For 0.1 wt% TMC, the crystallization half-time of the blend decreases from 39.41 to 3.97 min at 136 °C, compared with pure iPP. The isothermal crystallization data were further analyzed by the Avrami model. The values of the Avrami exponent of the blends are comparable to that of pure iPP, indicating that the presence of TMC does not change the crystallization mechanism of the matrix. The presence of TMC increases significantly the nuclei density of iPP but has no discernible effect on its crystalline structure, evidenced by polarized optical microscopy and wide angle X-ray diffraction measurements. [Copyright &y& Elsevier]

Highlights: [•] A pectin-coated liposomal formulations was prepared by forming an ion-complex. [•] The pectin-coated liposome has an excellent stability and mucoadhesiveness properties. [•] The pectin-coated liposome would be a promising drug carrier system for colon cancer. [ABSTRACT FROM AUTHOR]

Abstract: A grand canonical Monte Carlo-simulation (GCMC) study is presented focussing on the adsorption of CO2/CH4 mixtures in different nanopore models, including pristine mesoporous carbons, carbon foams, carbon nanotubes (CNTs), and nanopore models modified with hydrophilic carboxylic groups. We also report and discuss the selectivity of the different adsorbent surfaces under a wide range of temperature and pressure. Our results show that foam structures have the highest adsorption capacity of all the pristine structures studied because of its special architecture. The selectivity markedly enhanced after modification, especially at low pressures, and modified CNTs are found to have the highest selectivity among all the models tested. The effect of temperature and pressure is evaluated and the change in the selectivity trends of modified nanopore models are in contrast to that of the pristine models. The results suggest that the separation performance in carbon nanopores is greatly affected by the nature of the architecture and the heterogeneity of the materials. These findings could be beneficial in conventional pressure swing adsorption processes and the nanoporous structures could be used as parts of mixed polymer membranes. The results of this work present some guidelines for the designing nanoporous structures in order to achieve optimal separation of CO2/CH4 mixtures. [Copyright &y& Elsevier]

Abstract: Molecular dynamics simulations were performed to study the hydration of Na+ inside carbon nanotubes (CNTs) under external electric fields from 0 to 0.1V/nm. The simulation results show that the hydration of Na+ varies with the electric field intensity (E). The coordination number in the first hydration shell of Na+ increases with the increase of E. The analysis of orientation distributions for water dipole shows the Na+ hydration is strengthened when the direction of external field is aligned with the electric field generated by Na+, and is weakened when these are opposite. When E is aligned with the electric field of Na+, the strength of hydration is non-monotonic as E and reaches its maximum when E is equal to 0.01V/nm. This finding provides some guidance for the application of electric field in ion-transporting channels. [Copyright &y& Elsevier]

Highlights: [•] Extract of Crataegus pinnatifida pollen (ECPP) possesses antioxidant activity. [•] Eight phenolic compounds are determined in ECPP. [•] ECPP possesses stronger ability to protect plasmid pBR322 DNA breaks in site-specific system induced by hydroxyl radicals. [•] ECPP can protect against endogenous oxidative DNA damage in mouse lymphocytes. [ABSTRACT FROM AUTHOR]

A micro-sized B-Al alloy has application potential to be an energetic material for metal fuel. To understand the combustion mechanism of micro-sized B-Al compound powder and explosives containing B-Al (30 wt.%), the ignition and combustion characteristics of B-Al compound powder without and with HMX (cyclotetramethylenetetranitramine) under different pressures (0.4, 0.8, 1.2, 1.5 and 1.8 MPa) and atmospheres (60% O + 2 40 % N 2 , 80% O + 2 20 % N 2 and 100% O 2) were studied via a laser ignition experimental system. The images and characteristic parameters of the ignition and combustion process with different conditions for the B-Al compound powder without and with HMX were obtained. The effects of atmosphere and pressure on the ignition and combustion characteristics of the B-Al compound powder without and with HMX were discussed through a comparative analysis. For the condensed combustion products (CCPs), the phase crystal structures were analysed with X-ray diffraction (XRD), the micro-morphology of the surface was observed with scanning electron microscopy (SEM), and the micro-area elementary composition was analysed with X-ray energy dispersive spectrum (EDS). The results show that whether the increase in pressure or oxygen concentration, the ignition delay time (t id) and combustion time (t ct) of samples without and with HMX decrease, while the maximum spectral intensity (I max) and the maximum combustion temperature (T max) increase. According to the flame morphology, the combustion of the B-Al compound powder is weaker, while that of the B-Al powder with HMX is more intense, and the flame area is larger, which produces a large amount of smoke and presents a deflagration phenomenon. Specially, for various B-Al powder (B/Al = 3/7, 1/1 and 7/3) with HMX under high pressures (1.2, 1.5 and 1.8 MPa), the higher ratio of B leads to shorter combustion time and stronger spectral intensity. Unreacted B, Al and their final oxides, B 2 O 3 and Al 2 O 3 , were detected in the CCPs of both samples without and with HMX. In addition, the CCPs like BN, AlN and Al 5 O 6 N were also detected. The experimental results can help us better understand the chemical reaction mechanism and energy release characteristics of HMX-based explosives containing B-Al. [ABSTRACT FROM AUTHOR]

Phase transformation in low alloyed Fe-C steels during quenching and partitioning (Q&P), though authentically attributed to carbon diffusion, is scarcely quantified experimentally in terms of microstructural evolution and lack of fundamental backing at a quantum mechanics level. Herein, we report on a combined in-situ high energy synchrotron X-ray diffraction and density functional theory (DFT) study to unveil the physical mechanism of phase transformation in a Q&P processed advanced Fe-C steel. Beside a small fraction of bainite, a low air-quenching rate of ∼6 °C/s in the M s to quenching temperature range leads to carbon enrichment into the untransformed austenite, which simultaneously turns up with the later stage of martensitic transformation at the existing austenite/martensite interfaces. The resulting transformations are ascertained by DFT results and attributed to a second energy barrier in ferrite/martensite facilitation to carbon diffusion to austenite at elevated temperatures, along with the well-known carbon solubility difference/equilibrium in austenite and martensite. The development of cubic martensite in the carbon steel is theoretically elucidated and attributed to more probable hopping sites and diffusion paths of carbon in the ferrite/martensite than in the austenite. [Display omitted] [ABSTRACT FROM AUTHOR]

Neuron-specific enolase (NSE) is the preferred marker for monitoring small cell lung cancer and neuroblastoma. We devised a dual-signal ratiometric electrochemiluminescence (ECL) sensing strategy for sensitive detection of NSE. In this work, Ru (bpy) 3 2+ functionalized zinc-based metal-organic framework (Ru-MOF-5) nanoflowers (NFs) with plentiful carboxyl groups provide an excellent biocompatible sensing platform for the construction of immunosensor. Importantly, Ru-MOF-5 NFs possess stable and efficient "dual-potential" ECL emission of cathode (−1.5 V) and anode (1.5 V) in the existence of co-reactant K 2 S 2 O 8. Simultaneously, the cathode ECL emitter ZnO-AgNPs are employed as the secondary antibody marker, whose participation amplify the cathode ECL signal as well attenuate the anode ECL emission of Ru-MOF-5 NFs. By monitoring the ECL dual-signal of −1.5 V and 1.5 V and calculating their ratios, a ratiometric strategy of quantified readout proportional is implemented for the proposed immunosensor to precise analyze NSE. Based on optimization conditions, the ECL immunosensor displays the wide linear range of 0.0001 ng/mL to 200 ng/mL and the minimum detection limit is 0.041 pg/mL. The "dual-potential" ratiometric ECL immunosensor effectively reduces system error or background signal by self-calibration from both emissions and improves detection reliability. The dual-signal ratiometric strategy with satisfactory reproducibility and stability provides further development possibilities for other biomolecular detection and analysis. [Display omitted] • The single luminophore Ru-MOF-5 NFs showed "dual-potential" ECL emission. • The "dual-potential" of ECL emission was cathode (−1.5 V) and anode (1.5 V). • ZnO-AgNPs acted as both cathodic luminophore and anodic quencher. • The ratiometric immunosensor provided a novel strategy for NSE detection. [ABSTRACT FROM AUTHOR]

In this paper, the effect of compressive in-plane load on the equilibrium paths and vibration characteristics of a vertical symmetric laminated plate coupled with fluid is studied theoretically both in the pre- and post-buckling state. The Third-order shear deformation theory and von Karman nonlinear strain displacement relationship are utilized to describe the nonlinear deformation of the plate consists of a number of fiber-reinforced layers. The Hamilton's principle is introduced to formulate the plate-fluid coupled governing equations. A two-step theoretical approach is developed. Firstly, based on the Cylindrical arc-length method, we solve the nonlinear static equations to trace the snap-back behavior and pass the limit points along the complex equilibrium paths obtaining the stable buckling deflection. Then the coupled vibration characteristics are calculated using the tangent stiffness at the stable positions. The present theoretical results are validated by the numerical results. The effects of added mass and hydrostatic load are compared and analyzed. It is noted that, in the post-buckling state, the number of limit points along the static unstable equilibrium path increases with the compressive in-plane load getting larger. The variation trends of the natural frequencies and modes under different in-plane loads in pre- and post-buckling state are investigated. [ABSTRACT FROM AUTHOR]

Abstract: A novel label-free electrogenerated chemiluminescence (ECL) DNA-based biosensing method for the determination of trace bleomycin (BLM) was developed on basis of Fe(II)·BLM-mediated DNA strand scission and Ru(phen)3 2+ as an ECL probe. A thiolated ss-DNA, as substrate for BLMs, was self-assembled onto surface of a gold electrode to form a hairpin structure. Ru(phen)3 2+ was intercalated into the hairpin DNA structure. In the presence of Fe(II)·BLM, the hairpin DNA sequence undergoes the irreversible cleavage event under the oxidative effect of BLM with Fe(II) as a cofactor and the intercalated Ru(phen)3 2+ released from the gold electrode, which can be transduced into a significant decrease in ECL intensity. The ECL intensity versus the concentration of BLMs was linear in the range from 0.1pM to 50pM. The detection limit was 0.03pM. This work demonstrates that using the sequence selectivity of DNA cleavage strategy for the fabrication of the label-free ECL biosensing method is a promising approach for the determination of antitumor drugs. [Copyright &y& Elsevier]

Abstract: The aim of the present study was to investigate the antioxidant and hepatotective effects of Schisandra chinensis pollen extract (SCPE) on CCl4-induced acute liver damage in mice. Total phenolic content, total flavonoid content, individual phenolic compounds and antioxidant activities (1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, chelating activity, and reducing power assay) were determined. In vivo study, SCPE (10, 20 and 40g/kg) administered daily orally for 42days prior to CCl4-intoxicated. Our results showed that SCPE had high total phenolic content (53.74±1.21mg GAE/g), total flavonoid content (38.29±0.91mg Rutin/g), quercetin and hesperetin may be the major contributor to strong antioxidant activities. Moreover, SCPE significantly prevented the increase in serum ALT and AST level in acute liver damage induced by CCl4, decreased the extent of malondialdehyde (MDA) formation in liver and elevated the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in liver. The results indicated that SCPE has strong antioxidant activities and significant protective effect against acute hepatotoxicity induced by CCl4, and have been supported by the evaluation of liver histopathology in mice. The hepatoprotective effect may be related to its free radical scavenging effect, increasing antioxidant activity and inhibiting lipid peroxidation. [Copyright &y& Elsevier]

Abstract: To understand the antioxidant properties of buckwheat honeys, we investigated their antioxidant effects on hydroxyl radical-induced DNA breaks in the non-site-specific and site-specific systems, the physicochemical properties, antioxidant activities (1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical scavenging activity, chelating, and reducing power assays), total phenolic content and individual phenolic acids were also determined. Total phenolic content of buckwheat honeys ranged from 774 to 1694mg PA/kg, and p-hydroxybenzoic and p-coumaric acids proved to be the main components in buckwheat honeys. All the buckwheat honey samples possess stronger capability to protect DNA in the non-site-specific systems than in the site-specific systems from being damaged by hydroxyl radicals. In the non-site-specific and site-specific system, buckwheat honeys samples prevented OH-induced DNA breaks by 21–78% and 5–31% over control value, respectively. [Copyright &y& Elsevier]

Graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation is mediated by the activation of recipient dendritic cells and subsequent proliferation of donor T cells. The complement system was recently shown to modulate adaptive immunity through an interaction of the complement system and lymphocytes. Complement proteins participate in the activation of dendritic cells, antigen presentation to T cells, and proliferation of T cells. Our studies with a murine model of bone marrow transplantation demonstrate that complement system regulates alloimmune responses in GVHD. Mice deficient in the central component of the complement system (C3−/−) had significantly lower GVHD-related mortality and morbidity compared with wild-type recipient mice. The numbers of donor-derived T cells, including IFN-γ+, IL-17+, and IL-17+IFN-γ+ subsets, were decreased in secondary lymphoid organs of C3−/− recipients. Furthermore, the number of recipient CD8α+CD11c+ cells in lymphoid organs was reduced. We conclude that C3 regulates Th1/17 differentiation in bone marrow transplantation, and define a novel function of the complement system in GVHD. [ABSTRACT FROM AUTHOR]

Abstract: A novel, sensitive and high selective flow-injection chemiluminescence (FI-CL) method for the determination of phenol is reported, based upon its decreasing effect on the CL reaction of luminol with hydrogen peroxide catalyzed by manganese (III) deuteroporphyrin [MnDP, , 3] in alkaline solution. Under the selected optimized experimental conditions, the relative CL intensity was linear with phenol in the range of 4.0×10−9 to 4.0×10−7 gmL−1. The detection limit (3σ) was 6.3×10−10 gmL−1 and the relative standard deviation for 1.0×10−7 gmL−1 phenol (n =11) was 2.99%. The regression equation was I =120.79+1.14×1010c (R =0.9936). This method has been applied to the determination of phenol in water with satisfactory results. [Copyright &y& Elsevier]

The use of different available chlorine concentrations (ACCs) of slightly acidic electrolyzed water (SAEW; 0.5 to 30 mg/liter), different treatment times, and different temperatures for inactivating Escherichia coli O157:H7 and Staphylococcus aureus was evaluated. The morphology of both pathogens also was analyzed with transmission electron microscopy. A 3-min treatment with SAEW (pH 6.0 to 6.5) at ACCs of 2 mg/liter for E. coli O157:H7 and 8 mg/liter for S. aureus resulted in 100% inactivation of two cultures (7.92- to 8.75-log reduction) at 25°C. The bactericidal activity of SAEW was independent of the treatment time and temperature at a higher ACC (P > 0.05). E. coli O157:H7 was much more sensitive than S. aureus to SAEW. The morphological damage to E. coli O157:H7 cells by SAEW was significantly greater than that to S. aureus cells. At an ACC as high as 30 mg/liter, E. coli O157:H7 cells were damaged, but S. aureus cells retained their structure and no cell wall damage or shrinkage was observed. SAEW with a near neutral pH may be a promising disinfectant for inactivation of foodborne pathogens. [ABSTRACT FROM AUTHOR]

Abstract: A novel and ultrasensitive electrochemical approach for sequence-specific DNA detection based on signal dual-amplification with Au NPs and marker-loaded apoferritin NPs was reported. Target DNA was sandwiched between capture DNA coupled to magnetic beads and signal DNA self-assembled on Au NPs which were incorporated with marker-loaded apoferritin NPs. Subsequent electrochemical stripping analysis of the electroactive markers released from apoferritin NPs in acidic buffers provided a means to quantify the concentration of target DNA. In this means, one target signal could be transformed into multiple redox signals of the markers since a single Au NP could be loaded with dozens of apoferritin NPs, and an apoferritin NP could be loaded with thousands of markers. Under the optimum conditions, the linear range was from 2.0×10−16 to 1.0×10−14 M and the detection limit was 5.1×10−17 M by using the cadmium as a model marker. The proposed DNA biosensor not only exhibited excellent sensitivity but also had good reproducibility and selectivity against two-base mismatched DNA. [ABSTRACT FROM AUTHOR]

Abstract: Restoration of lymphatic drainage using lymph vessels or tissue grafting is becoming an efficient method for alleviating obstructive lymphedema. However, the lack of ideal lymphatic grafts is the key problem that limits the application of lymphatic transplantation, but now that may be resolved with tissue-engineered lymph vessels. In this study, the feasibility of reconstructing lymph vessels was explored using lymphatic endothelial cells (LECs) combined with polyglycolic acid (PGA) scaffolds. The highly purified human dermal LECs can be isolated from human dermis by immunomagnetic bead sorting and multiplied in culture. The viability and growth potential of subcultured LECs make it possible to obtain large amount of cells in vitro. Light and scanning electron microscopy (SEM) showed that the prefabricated PGA scaffolds, with three-dimensional structure, can support cell adhesion, growth and spreading. The constructs formed with LECs combined with PGA scaffolds were cultured in vitro for 10 days and then implanted subcutaneously into nude mice. Six weeks after implantation, the portions of implanted tubules were harvested. Gross and histological observation demonstrated that the tubular structure still remained in the experimental groups but not in the control groups. Immunohistochemical staining and RT-PCR assay of the implanted vessels revealed positive staining in experimental groups for the lymphatic specific markers Podoplanin, VEGFR-3 and LYVE-1. The results indicate that LECs can serve as seed cells and be successfully combined with PGA scaffolds, and the tissue-engineered tubular structure using implanted LECs–PGA compounds showed preliminary characteristics of lymph vessels. A gap between the nearly normal or functional lymph vessel still exists as we have only the endothelial cell-lined duct, but this study demonstrates that it is feasible to construct tissue-engineered lymph vessels using LECs combined with a biodegradable material. [ABSTRACT FROM AUTHOR]