Abstract:The high temperature tensile properties and room-temperature mechanical properties of 2024Al/Gr/SiCp hybrid composites after long time thermal exposure were studied. The fractures of 2024Al/Gr/SiCp hybrid composites after a long time of thermal exposure at different temperatures were observed by SEM. The results show that the mechanical properties of 2024Al/Gr/SiCp hybrid composites decrease slightly with the increase of exposure time at 200 ℃. The 2024Al shows a greater decline of mechanical properties than the composites, which is attributed to the addition of SiCp particles and flaky graphite. The mechanical properties of the materials decrease rapidly due to the coarsening of precipitates and grain. The tensile strength at elevated temperatures decreases with the increase of test temperature. The 2024Al is characterized by ductile fracture, while the composites are characterized by the ductile fracture of matrix, the tearing of the graphite and the interface between the particles and matrix.

Abstract:Isothermal compression tests of extruded CuCr25 alloy were carried out at the temperature range of 750~900 ℃ and at the strain rate range of 0.01~10 s-1 on Gleeble-3500D system. The experiment results showed that the flow stress decreased with the increase of deformation temperature and the decrease of strain rate, which could be described by hyperbolic-sine equation with the average hot deformation activation energy Q of 383.4 kJ/mol. The processing maps were calculated on the basis of the dynamic materials model. The optimum processing parameters were proved to be the deformation temperature range of 830~900 ℃ and the strain rate range of 0.01~0.1 s-1 was obtained by processing maps and deformed microstructural observation.

Abstract:The evolution of microstructures and the properties of 2A66 Al-Li alloy during artificial aging was studied with differential scanning calorimetry (DSC), hardness measurement, tensile testing, scanning electron microscope (SEM) and transmission electron microscope (TEM). The results indicate that the strength can reach the peak value with the increase of aging time, and the higher the aging temperature, the shorter the time for peak value. The best aging process for peak value of 2A66 Al-Li alloy ages at 165 ℃ for 64 h and the alloy gets a good combination of strength and plasticity. Its hardness, σb, σ0.2 and δ are 146HB, 526.5 MPa, 448.9 MPa, 10.1%. The δ', θ' and T1 phases are the major precipitates of 2A66 alloy ageing at 165 ℃. At the early stage of aging, the main source of strengthening for the alloy is the GP zone, δ' phase and θ' phase. At the peak of aging, the θ' phase and T1 phase are the main strengthening phases.

Abstract:Nano-CaCO3 was adopted into cement-based materials in the ultrasonic dispersion method. The influence of nano-CaCO3 with different contents on the properties and structures of cement-based materials was studied, and its mechanism was investigated by X-ray diffraction and scanning electron microscope. The results show that the fluidity is decreased, the apparent density of cement paste is increased, and the flexural strength and compressive strength are improved due to the addition of nano-CaCO3. The mechanical properties of cement-based materials containing nano-CaCO3 of 1.5% (in mass) are significantly improved. However, excessive dosage of nano-CaCO3 goes against the improvement of strength. The hydration can be accelerated, the hydration products such as Ca (OH)2 increase with the addition of nano-CaCO3 at the early age; the interface transition zone between aggregate and cement paste and the microstructure of hardened cement paste are greatly improved so that the whole structure can get more dense and homogeneous. The above results indicate that the incorporation of nano-CaCO3 is good for the physical properties and structures of cement-based materials.

Abstract:By using ethylene diaminetetraacetic acid (EDTA) and citric acid as the complexants, hydroxyapatite (HA) coatings were fabricated by means of one-step micro-arc oxidation (MAO) in the acid electrolytes containing Ca2+ and P5+ions. With the increase of Ca/P in the electrolytes, the content of HA in the coatings obviously increased and the coatings possessed coarser surfaces with fine and well-distributed pores. The results of animal experiments have indicated that the inflammatory reactions induced by implant buttons with HA coatings were minor and the new musculature could grow on the surfaces of the coatings.

Abstract:To improve the accuracy of the fracture parameters of interface fracture structure, based on the interfacial fracture mechanics and smoothed finite element method, Cell-Based smoothed finite element method was proposed to solve the fracture parameters of bi-material interface crack, and the smoothing cells of the interaction integral method was given to obtain the stress intensity factor. The central interface cracks of bi-material infinite plate were simulated, and the FEM calculation results and the analytical solution were compared. The relationships among the number of elements, the number of subdomain and normalization stress intensity factors as well as the convergence of the proposed method were discussed. Numerical example results show that this method has good convergence and high accuracy and can be designed and manufactured as necessary references for researchers and engineers in multilayer materials.

Abstract:The mechanical blending method was used to prepare the micro/nano inorganic particle modified PU-EP composites. The influence of the composition and the amount of the particles on the properties of the PU-EP composites were studied, and the toughness mechanism of the obtained composites was also discussed. The results show that the addition of nanoparticles can noticeably improve the interlaminar shear strength and the tensile strength of the PU-EP composites, while reducing the elastic modulus and changing its fracture behaviors. When the content of the nano-SiC particles equaled 2%, the interlaminar shear strength and tensile strength of the composites reached 4.47 MPa and 56.56 MPa, an improvement of about 88% and 74% compared with that of un-modified composites. Also, the temperature corresponding to different weight-losses of the nano-SiC particle modified composites was improved by about 4~8 ℃. The nanoparticles dispersed and strengthened the blunt of the silver strip, which played an important role in the course of the toughness mechanism of the composites.

Abstract:Two azobenzene gelators (M-AZO-1 and M-AZO-2) with melamine moieties were designed and synthesized. The two gelators can gel many kinds of organic solvents with a low concentration. The SEM images of the xerogels showed fibers with larger diameter formed in polar organic solvents such as ethyl acetate, and fibers with smaller diameters formed in apolar organic solvents such as toluene and methyl cyclohexane. The effect of UV irradiation on gelation behavior was further investigated. After the irradiation of 365nm light, M-AZO-1 and M-AZO-2 could still gel the same solvents and the morphologies of aggregations remained unchanged obviously.

Abstract:3D nitrogen-doped graphene (NRG) was prepared in the hydrothermal method with graphene oxide (GO) as the raw material and melamine as the nitrogenous source and reducing agent. Scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, nitrogen adsorption-desorption analysis and electrochemical measurements were used to characterize the morphology, structure, components and supercapacitor performance of as-prepared electrode materials. The results showed that GO could be reduced efficiently by melamine and realized N-doping at the same time. The 3D structure was built due to the strong interaction between graphene sheets. Its content of nitrogen atoms was 4.37%. The electrochemical performance was measured through electrochemical tests. When the mass ratio of GO and melamine was 1∶2 (NRG-2), the highest specific capacitance of 296 F/g can be achieved at the current density of 1 A/g, which was higher than the capacitance of other mass ratios of GO and melamine. 88.5% of the capacitance of NRG-2 remained after 1000 cycles, which meant that NRG-2 had a long life cycle.

Abstract:High strength carbon materials were made with activated petroleum coke powder as the raw material, coal pitch as the binder under different molding pressures and holding time. The mechanical properties of the samples were tested, and SEM, TG-DTA, XRD were analyzed. The interaction mechanism of the raw materials and the binder was clarified. The results have shown that, the properties of the roasted samples increase with the pressure holding time and the molding pressure. In the holding time of 20 min, the molding pressure is 200 MPa, the bulk density of the roasted sample reaches 1.54 g/cm3, the compressive strength is 119 MPa and the flexural strength is 61 MPa. They are all better than the samples made without activated petroleum coke powder as the raw material.

Abstract:Based on 80V2O5-20P2O5-xSb2O3(x=0,1,3,5 mol%) system glass and heating 1 h at 850 ℃, a glass sample was successful prepared. The mechanism of the increased crystallization stability of Sb2O3-doped vanadium phosphate sealing glass was investigated with infrared absorption spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and nuclear magnetic resonance (NMR) . The tests showed that, by introducing Sb2O3 into glass system, the amount of BO increased while NBO decreased, and part of the NBO structure broke and turned into BO structure. Meanwhile, with the increase of V4+/V5+, these two factors led to the breaking of V=O bond, which was essential for the formation of V2O5 crystalline phase and inhibited the formation of the crystalline phase. By introducing Sb2O3 into the glass system, the amount of (V2O8)n zigzag chain increased while (VO3)n single chain decreased. The intermediate structure of the network equilibrium was destroyed by the introduction of Sb2O3.The (VO3)n single chain was gradually transformed into (V2O8)n zigzag chain and the glass structure became tighter. It was difficult to crystalline. The crystallization stability of glass was improved.

Abstract:Two types of pitch carbon-coated artificial graphite were prepared in the vacuum liquid impregnation method, while the coating agents were medium pitch and modified pitch dissolved in THF solutions. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to characterize the structure of the carbon-coated graphite and artificial graphite. Li-lion batteries were assembled and their electrochemistry performances were evaluated. The results have shown that the pitch carbon has been coated on the surface of the artificial graphite particles. Meanwhile, the average pore diameter decreases due to the carbon coating. The carbon coating increases the disorder degree on the surface of the artificial graphite. However, the crystal structure of the artificial graphite remains the same. The BET specific surface area of the carbon-coated artificial graphite derived from the modified pitch decreases from 4.27 m2/g to 1.65 m2/g. Its initial coulombic efficiency increases by 3.5%, and its irreversible capacity decreases by 10.9 mAh/g. Meanwhile, the cyclic performance has been enhanced.

Abstract:The mechanical properties of ductile iron samples containing 0.25% molybdenum and 0.2%~0.8% nickel were tested after being annealed at a low graphitization temperature. The microstructure and impact fracture were observed and analyzed. The ferrite content of ductile iron was increased after adding a small amount of molybdenum and nickel. Consequently, the impact toughness was increased by more than 50% while the strength and the hardness were decreased. The pearlite in the ductile iron was gradually transformed into ferrite after low temperature annealing. The impact toughness was increased substantially and the impact absorbed energy was increased to 500% compared with cast ductile iron samples. Many tearing ridges and dimples were found on the impact fracture through SEM observation. The mechanical properties in different annealing parameters were relatively more stable with a smaller fluctuation after molybdenum and nickel were added.

Abstract:A kind of repair mortar for geotechnical building was prepared with lime and metakaolin as major materials. Two kinds of water-repellent admixtures (tung oil and calcium stearate) were used to improve the water resistance of the mortars. Different properties of the mortars were evaluated， such as strength, the process of reaction, water absorption, softening coefficient and shrinkage. Phase and microstructure analysis of the mortars were carried out through XRD and SEM. The results show that tung oil and calcium stearate can improve water resistance of the mortars significantly. Water absorption of the mortars with tung oil or calcium stearate can be below 2.5%.Tung oil and calcium stearate hinder the pozzolanic reaction of metakaolin, which as a result decrease the mortars’ strength. But 28 d compressive strength of the mortars are all above 5 MPa. Also, tung oil and calcium stearate can regulate the growth of products and affect the micromorphology and structure of mortars. Tung oil make the particle size smaller and the structure more compact, while calcium stearate leads to a looser structure. Considering both the mortar strength and water resistance, the optimum dosage of tung oil and calcium stearate was 5% and 1.5% respectively.

Abstract:Series of the hydroxyl-terminated co-polyethers whose molecular weight is around 2 000 were synthesized by controlling the rate of THF and ECH and the dosage of initintor. Varied types of modified UV curable waterborne polyurethane emulsions were synthesized by using the co-polyethers acting as soft segment, and the corresponding product structures were characterized by using FTIR. The results have shown that: with the increasing ratio of epoxy chloropropane, the strong polarity halogen atoms in the soft segment increases while the tensile strength of curable film changes from 4.6 MPa to 6.7 MPa and the elongation at break reduces from 162% to 113%. When the ratio of THF and ECH grows to be 1∶1, the weightlessness temperature of 5% and 10% increases from 164 ℃ to 200 ℃ and 220 ℃ to 275 ℃. In addition, the adhesion of the coating significantly increases to 1 level, also the hardness and impact resistance performance improves.

Abstract:By comparing the dynamic interfacial tension (DIFT) of oil/alkali and oil/alkali-surfactant, it was found that, compared with O/A system, the interfacial tension of O/AS system was higher at lower alkaline concentration and lower at higher alkaline concentration. It was also found that OH- played an important role in increasing oil/Alkali interfacial tension by comparing the DIFTmin of Oil/NaOH and oil/NaOH-NaCl under similar ionic concentration. It was also observed that the amount of oil components diffusing into water phase increased with the decrease of interfacial tension. The oil droplet contracted during the measurement of interfacial tension after the oil components left the oil/water interface. Combining all the results together, the synergism between alkali and surfactant for reducing oil/aqueous solution could be deduced as: alkali reacted with oil to form in situ surfactant，added surfactants to stimulate the diffusion of in situ surfactants. Therefore, more surface active components in oil could diffuse to O/W interface, thus producing more in situ surfactants to reduce the oil/water IFT.

Abstract:With vinyl acetate(VAC) as the hard monomer, butyl acrylate (BA) and 2-Ethylhexyl acrylate (2-EHA) as the soft monomer, acrylic acid(AA) as the crosslinking monomer, polyvinyl alcohol (PVA-1788) as the protective colloid, alcohol polyoxyethylene ether(AEO-9) and sodium dodecyl sulfate (SDS) as the emulsifier, potassium persulfate (K2S2O8) as the initiator, hardcore soft shell emulsion was synthesized. The core-shell particle structure was designed. The effect of soft and hard monomer, protective colloid, emulsifiers on tack, viscosity and size and distribution of particles of adhesives were studied. The results have shown that the hardcore softshell vinyl acetate-acrylate emulsion adhesives have good tack, low viscosity and narrow distribution of particle size. It can meet the requirements of high-speed cigarette filter tipping for punching water-paper.

Abstract:To identify proteins interacting with transcription factor FOXA1，different prokaryotic expression vectors for human FOXA1 protein were constructed and the proteins of FOXA1 C-terminus and FOXA1 N-terminus were purified. They provided a material foundation for future studies of FOXA1-interacted proteins. Total RNAs were extracted from human breast cancer MCF7 cells and reverse transcribed into cDNAs. The full length cDNA of FOXA1 was amplified by PCR, and the C-terminal and N terminal segments were also amplified respectively. The different FOXA1 cDNA fragments were cloned into a prokaryotic expression vector pGEX-4T-1. The correct vectors were confirmed by double restriction enzyme digestion and DNA sequencing and transformed into E. coli BL21 Rosetta DE3. The FOXA1 proteins were purified with Glutathione Sepharose 4B and analyzed through SDS-PAGE electrophoresis and Western blot. GST Pull-down experiments were performed with lysates of MCF7 cells and FOXA1 proteins to test the interaction between FOXA1 and a known FOXA1-interacted protein TLE3.Prokaryotic expression vectors of pGEX-4T-1-FOXA1-C and pGEX-4T-1-FOXA1-N were constructed successfully. The proteins of FOXA1 C-terminus (GST-FOXA1-C) and FOXA1 N-terminus (GST-FOXA1-N) were purified by Glutathione Sepharose 4B. It was confirmed that the purified GST-FOXA1-C was able to interact with the known FOXA1-interacted protein TLE3 in the Pull-down experiment.

Abstract:Os11g39000 is a member of atypical bHLH transcription factor family in rice, and its function remains unclear. Yeast two-hybrid experiments revealed that the transcription factor Os11g39000 could form a homologous protein polymer. Random binding site selection demonstrated that Os11g39000 could bind to DNA, and its binding site was preliminarily identified as TT/CG/CACC/GT/C. Expression pattern analysis discovered that the Os11g39000 gene was mainly expressed in leaves and roots, which was a speculation that Os11g39000 may play a role in the developmental regulation of leaves and roots. The hydroponic experiments showed that, compared with wild-type plants, the loss-of-function transgenic plants exhibited much shorter roots and obvious defect in root development, indicating that Os11g39000 was involved in the developmental regulation of roots. Q-PCR analysis further revealed that the transcriptional levels of auxin biosynthesis and signal transduction related genes increased significantly in loss-of-function transgenic plants. These results together demonstrated that the transcription factor Os11g39000 was involved in the regulation of auxin biosynthesis and signal transduction.

Abstract:To address polymer flooding emulsion in high water cut crude oil demulsification and oil-water separation, the bottle test method for the screening of a class of polymer containing liquid oil-water separation was used and the oligomeric quaternary ammonium salt I was found to show excellent demulsification performance, When ammonium salt I was added with the concentration of 25 mg/L, and the emulsion was demulsificated at 55 ℃ for 60 min, the dehydration rate reached 96.5%. Compared with conventional polyether or polyamines demulsifiers, the quaternary ammonium salt I made the solution clearer and oil-water interface neater. The mechanism of the quaternary ammonium salt I affecting the emulsion was studied with optical microscope, dynamic analyzer and contact angle analyses. It was shown that free water in the oil droplet coalescence separation zone accounting for a leading role was instable and the emulsion oil droplet moved upward when oligomeric quaternary ammonium salt I was added to polymer flooding produced water. Being immersed, the solution of ammonium salt I on the surface of the pore core turned to water wet state. The result showed that changes of the interfacial wettability of the pore core on the membrane emulsification of strong dissolving capacity might lead to the rupture of the liquid film and oil-water separation. The contact angle measurement showed that the salt I of the liquid surface of the emulsion changed to water wet state, the strong wettability of the emulsion film was caused by the change of the film breakup, and the oil water was successfully separated.

Abstract:A novel catalyst, nikel ferrite (NiFe2O4), was prepared via hydrothermal synthesis method, and successfully used to activate peroxymonosulfate for degradation of oxcarbazepine (OXC). The catalyst was characterized by scanning electron microscopy (SEM), X-ray diffractometry (XRD), and magnetic hysteresis loops.The effects of NiFe2O4 dosage, peroxymonosulfate dosage, and initial pH on the OXC degradation were investigated.The experimental results indicated that high NiFe2O4 and peroxymonosulfate dosages, neutral initial pH enhanced the degradation efficiency. Furthermore, by adding different radical scavengers (TBA and MeOH), hydroxyl radical (OH·) and sulfate radical (SO4-·) were identified to be responsible for OXC degradation and SO4-·made the predominant contribution. Besides, NiFe2O4 could retain high degradation efficiency around 88% even after being reused for six times. The catalytic oxidation of OXC in filtrate and raw water with PMS/ NiFe2O4 system was also effective. All results suggest that oxidation of PPCPs such as OXC using PMS/ NiFe2O4 system has a promising application potential.

Abstract:Samarium-doped ZnO Nanoparticles were synthesized via a facile and surfactant-free solvothernal method after calcined 3 h at 400 ℃. The prepared nanostructures were characterized by UV-vis spectrophotometer, scanning electron microscopy (SEM), energy dispersive spectrum analysis (EDX) and Fourier transform infrared spectroscopy(FTIR).The SEM images show that the synthesized ZnO nanoparticles are regular hexagonal columnar body. And the morphology of the nanostructures is not changed after doped Sm，while the crystal volume of ZnO-Sm nanoparticles become smaller. The EDX spectrum depict that Sm ions are successfully doped into ZnO. The photocatalytic studies show that the ZnO-Sm(2.0%) photocatalytic degradation of RhB enhanced approximately 30% under visible light irradiation compared with the pure ZnO. And in order to obtain the best photocatalytic effect, the optimal experimental conditions were explored. As such, ZnO-Sm nanostructures were indicated great potential for practical applications in wastewater treatment.

Abstract:Formation and decay of different forms of chloramines were analyzed in stainless steel loop. The experimental results show that under the Cl/N ratio of 1~12, the formation of free chlorine, monochloramine and total chlorine in different water qualitity follows the ranking of deionized water> bulk water > stainless steel loop; the formation of dichloramine in stainless steel loop is much higher than that in deionized water and bulk water, at Cl/N ratio of 10, it accounts for more than 90% of the total chlorine. Under different Cl/N ratio, dichloramine first increases and then decreases with time and other forms of chloramines continuously decrease with the reaction time. The decay rate of monochloramine under different Cl/N ratio follows as: 6∶1 > 3∶1 > 4∶1 > 5∶1, the concentration of dichloramine has no obvious correlation with Cl/N ratio.

Abstract:Natural clinoptilolite were modified by five different valence state cationic salts. The differences of adsorption ability to ammonia nitrogen were studied with particle morphology, channel characteristic, cation exchange capacity and adsorption ability to ammonia nitrogen taken as evaluation indexes. EDS test revealed that the metal cation content corresponding to five kinds of modified salts in the clinoptilolite will increase with K+ increasing most in KCl modified clinoptilolite. The results of specific surface area and pore size distribution test indicated that the specific surface area of KCl modified clinoptilolite decreased least, whereas AlCl3 modified zeolite dropped most. The mesoporous volume of NaCl and KCl modified clinoptilolite increased most, but macroporous volume reduced most.However the clinoptilolite modified by MgCl2 and CaCl2 showed little change. Cation-exchange capacity order of the modified zeolite was NaCl＞AlCl3＞CaCl2＞MgCl2＞KCl. The ability of clinoptilolite for removing ammonia nitrogen was found to be positive correlation with cation-exchange capacity, but there was a big difference in the cation-exchange capacity of salt modified zeolite with the same valence. The results indicated that the cation valence was not positive correlation with cation-exchange capacity and ammonia nitrogen removing ability.

Abstract:This study was performed to analyze the distribution, contamination degree and human health risks of traffic-related heavy metals (HMs) in roadside soils along G4 highway and G60 highway in Hunan province, China. A total of 45 composite soil samples from three sampling sites (LC, CT, and TS)with different distance (5 m，10 m，15 m，40 m，or 80 m) were analyzed for HMs concentrations of Zn, Pb, Cd, Cr and Cu. The results showed that the concentrations of those HMs in roadside soils decreased with the increasing distance from highways. A pollution assessment by Geo-accumulation Index (Igeo) showed that the pollution level for the HMs is in the following order: Cd＞Pb＞Cr＞Zn＞Cu. The Cd levels can be considered “heavily contaminated” status in the distance of 5 m. And Cd also presented high risk based on potential ecological risk indexes (RI). The other detected heavy metals are practically uncontaminated or uncontaminated to moderately contaminated. The health risk of HMs in highway roadside soils was evaluated by hazard index (HI) and cancer risk (CR). The results showed high HI for Cd, Cr and Pb, indicating a potential human health risk for both adult and children in these areas. But cancer risk of all those HMs for both adult and children was acceptable. Cr in three studied sections showed a slight cancer risk (carcinogenic risk in the acceptable range) in the distance of 80 m, which indicated the residents around highways should be living outside the distance of 80 m.