Abstract:The effect of water toughening treatment on mechanical properties of high manganese steel bonded TiC hard alloy was systemically investigated, and the microstructure and element distribution of the alloy before and after the treatment were also evaluated by SEM and EDS in order to understand the internal relationship of its properties. The bending strength and impact toughness of high manganese steel bonded TiC hard alloy by normal vacuum sintering were raised by 154.6% and 125.3%. They were 61.81%, 45.38% and 65.59%, 32.90% for low pressure sintering and vacuum sintering plus low pressure sintering specimen, respectively. The results revealed that water toughening treatment could effectively improve the alloy's bending strength and impact toughness.

Abstract:Hard carbon anode containing boron atoms for lithium ion batteries was synthesized by adding boric acid in the pre-carbonized precursor of phenolic epocy resin. The micro-structures of materials were characterized by X-ray diffraction, scanning electron microscope and other technical means. The pore characteristics and specific surface areas were determined in nitrogen absorption method. The electrochemical performance of anode was analyzed by cyclic voltammetry, electrochemical impedance spectra and galvanostatic charge and discharge experiments.The results show that the layer distances, specific surface area, pore volume and initial irreversible specific capacities decrease and the initial coulombic efficiency increases with the increase of the content of boric acid. The reversible capacity increases from 332.2 mAh·g-1 to 461.1 mAh·g-1 and the corresponding resistance of solid inter-phase film decreases from 33.86 Ω to 24.53 Ω when the doping content of boric acid reaches 10%.

Abstract:In this research, the jute fibers were first treated with heating, alkali, silane coupling agent and isocyanate respectively, then the jute fibers fabrics were treated with hot pressing process, and finally, the jute fiber reinforced epoxy resin composites were fabricated with VARTM molding process. Scanning Electron Microscopy (SEM) analysis shows that the interface bonding of jute fibers treated with heating and alkali reinforced epoxy resin composites has not been improved, but the interface bonding of composites has been significantly improved with the jute fibers treated with silane coupling agent and isocyanate. The hot-pressing process can not only increase the jute fibers volume content in the composites but also improve the performance of composites by the jute fibers treated in advance with silane coupling agent and isocyanate. The mechanical properties of the composites show that tensile strength, modulus and flexural strength of the jute fiber treated with the silane coupling agent reinforced composite increase by 18.6%, 71.4% and 50.2%, respectively, and the tensile strength, modulus and flexural strength of the jute fiber treated with the isocyanate reinforced composite increase by 16.3%, 34.0% and 50.3%, respectively.

Abstract:By using DSC/TG, SEM, BET, particle size distribution and hydration temperature curve, the pyrolysis characteristics and mechanical properties of phosphorus recycled gypsum, desulphurized recycled gypsum and their changing mechanism were studied. The results indicated that the pyrolysis characteristics and mechanical properties of recycled gypsum were decreased, the twice dehydration temperatures of phosphorus recycled gypsum dropped 4℃ and 2℃, respectively, and desulphurized recycled gypsum both reduced by 2℃. The low decrease in strength and modest increase in water absorption were seen in phosphorus recycled gypsum, and the rate was 15%~30% and 22.40%, respectively. But the 45%~70% decrease in strength and 76.61% increase in water absorption were possessed by desulphurized recycled gypsum, which was much greater than phosphorus recycled gypsum, and approximately the same dehydration temperatures and mechanical properties were observed by the two recycled gypsum. The analysis has shown that the reduction in pyrolysis characteristics is due to the decrease of particle sizes in recycled gypsum. The main reason of the great difference of mechanical properties between raw gypsum and their recycled gypsum are the increase in specific surface area, decrease in particle sizes and the uneven distribution of recycled gypsum. And the poor crystal of phosphorus gypsum results in the low decrease rate of its recycled gypsum.

Abstract:Non-isothermal crystallization transformation kinetics and isothermal crystallization kinetics of prepared Zr57.5Cu27.3Al8.5Ni6.7 bulk metallic glass (BMG) were investigated with differential scanning calorimetry (DSC). In isochronal mode, the values of activation energy, Eg, Ex, Ep1 and Ep2, calculated by Kisinger method are 409.70 kJ/mol (± 60.07 kJ/mol), 335.53 kJ/mol (± 39.94 kJ/mol), 323.95 kJ/mol (± 15.21 kJ/mol) and 187.75 kJ/mol (± 13.27 kJ/mol), respectively. In isothermal mode, the S-shape relation curves of crystalline volume fraction and temperature reveal the typical transition of nucleation and growth. The Avrami exponent n ranges from 3.0 to 4, indicating the crystallization mechanism in the Zr57.5Cu27.3Al8.5Ni6.7 BMG is mainly interface-controlled. The crystal growth way changes from two-dimensional growth with decreased nucleation rate to three-dimensional growth in the isothermal crystallization process. In isothermal mode, the mean value of activation energy is 434.81 kJ/mol, which is higher than that in the isochronal mode.

Abstract:A pure iron (1 mm in thickness) was gas nitrided at 580 ℃ for 4h, followed by oil quenching or furnace cooling. The oil-quenched samples were first naturally aged (NA), and then artificially aged between 100 ℃and 140 ℃. The microstructural examinations and property characterization were investigated using X-ray di?ractometer, scanning electron microscope, transmission electron microscope, Vickers hardness tester and fatigue tester. It was found that the nitrided samples consisted of compound layers (CLs) and diffusion layers (DLs). The cooling method did not change the thickness of the CLs and the phase constitutes of the upper-most layer, but had remarkable effect on the microstructure and mechanical property of the DLs. A great quantity of rich-N clusters precipitated from the oil-quenched DLs after natural ageing for 200h, and the oil-quenched DLs had a great natural ageing strengthening phenomenon. During artificial ageing (AA), the type and number of precipitates could be controlled by the ageing temperature and ageing time. The main precipitates are the α″-Fe16N2 during lower temperature ageing while it is the γ′-Fe4N at higher temperature ageing. The NA samples could get very high hardness and strength. The hardness and strength of the AA samples decreased with the increase of ageing temperature. The high temperature ageing greatly improves the elongation of the oil-quenched samples. The CLs had little effect on the tensile stress of the nitrided samples, but greatly decreased the fatigue strength under the tensile.

Abstract:The microstructure, mechanical properties and corrosive behavior of the 3.5wt%NaCl solution of the as-cast and the as-extruded Mg-4.5Zn-4.5Sn-2Al alloy were investigated. The results show that the average grain size of the as-cast alloy is 183 μm and that of the extruded alloy is 9 μm. Compared with as-cast alloy, the tensile strength of the extruded alloy increases from 209 MPa to 354 MPa, the yield strength increases from 157 MPa to 216 MPa, and the elongation reaches about 19.6%. The tensile fracture of the extruded alloys exhibits ductile fracture. Static immersion corrosion tests and electrochemical measurements show that the corrosion resistance of the extruded alloy is obviously inferior to that of as-cast alloy.

Abstract:The effect of quenching rate on the exfoliation corrosion of Al-5Zn-3Mg-1Cu aluminum alloy thick plate was investigated by means of end-quench technique, corrosion immersion test, optical microscopy, transmission electron microscopy and scanning and transmission electron microscopy. The resistance to the exfoliation corrosion of Al-5Zn-3Mg-1Cu aluminum alloy thick plate decreases with the decrease of quenching rate (from 2 160 ℃/min to 100 ℃/min), and exfoliation corrosion rate is from P to ED with the maximum corrosion depth increasing from 15μm to 530μm. The decrease of quenching rate leads to a larger amount of second phase particles at grain boundaries, a higher concentration of Zn and Mg in them and wider precipitate free zone near grain boundaries, which was the main reasons for lower resistance to exfoliation corrosion.

Abstract:Two most abundant sources with the highest anticancer activity of natural polymethoxyflavonoids were oxidated by dimethyldioxirane ( DMDO ) to polymethoxy flavonoids 9 and 10 respectively. 9 or 10 were condensed with α-acetylglucosyl bromide, α-acetylgalactosyl bromide or α-acetylrhamnosyl bromide in dilute NaOH (aq)/CHCl3 system through phase transfer catalytic glycosation reaction, and followed by deacetylation, four new polymethoxyflavonoids glycosides 1~4 were synthesized. The structures of all the synthesized compounds were characterized by 1HNMR, 13CNMR and MS spectra. This synthetic method has the advantages of easy availability of starting materials，simple operation．

Abstract:Amorphous Ni-P and Ni-Sn-P coatings were prepared on pure copper substrates by electroless plating. The structure, surface morphology and composition of the as-plated coatings were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive analysis (EDS). The corrosion resistance behaviors of the as-plated Ni-P and Ni-Sn-P coatings were investigated by Tafel polarization, electrochemical impedance spectroscopy (EIS), open circuit potential and accelerating corrosion indoors in wNaCl=3.5% solution at pH 5.5 and in soil with a water content of wS=20% at pH 5.5. The results indicate that electroless amorphous Ni-P and Ni-Sn-p plating of the corrosion current density is 4.5% and 1.2% of the bare copper and the two coatings offer better corrosion resistance than copper in weak acidic corrosive medium, while Ni-Sn-P coating exhibits the best corrosion resistance. Besides, the two coatings have a negative shift of self-corrosion potential when compared with Cu substrate, showing a good application prospect as anodic protective coatings for Cu ground wires in acidic or weak acidic soil medium.

Abstract:Solid superbases Rb2O/γ-Al2O3were prepared from rubidium salts separated from salt brine. Sucrose was used as the template, Rb2CO3 (prepared from RbCl) and Al(NO3)3 as the raw materials, we prepared Rb2O/γ-Al2O3 successfully by using in-situ method. In impregnation method, we first used sucrose as the template, Al (NO3)3 and Al［CH(CH3)2］3 as aluminum sources, respectively to prepare γ-Al2O3,and then a series of Rb2O/γ-Al2O3 with different rubidium contents through the impregnation of RbNO3 (prepared from RbCl). The base strength of Rb2O/γ-Al2O3 both can reach 26.5 or more, belonging to superbase prepared through the two methods by controlling the conditions. The prepared Rb2O/γ-Al2O3 solid superbases were used to simulate interesterification in the process of producing biodiesel by catalyzing triglycerides acetate and methanol. The optimum reaction conditions were as follows: the ratio of alcohol to ester was 8∶1, the reaction temperature was 338 K, the reaction time was 4 h, and the amount of catalyst is 6.0% of the weight of ester. Under those conditions, the productivity of methyl acetate was up to 98%.

Abstract:The UV-curable waterborne polyurethane was synthesized by using isophorone diisocyanate (IPDI), polytetrahydrofuran (PTMEG), dimethylol propionic acid (DMPA), and hydroxyl-terminated polystyrene (HTPS) as materials. The rigid phenyl group was introduced into the UV-curable waterborne polyurethane (UVWPU) structure to improve heat resistance and hardness of the coating film, and the product was confirmed using FT-IR. The effects of curing parameter, dosage of DMPA and HTPS on the properties of coating and emulsion stability were discussed. The results show that the storage stability of the emulsion is over 6 months when the amount of DMPA is above 6 %, and the coating film exhibits excellent appearance and good properties when the curing parameter is above 1.35. The weight-loss temperature of 5 % and 10 % is respectively 245 ℃ and 282 ℃, which is higher 32 ℃ and 27 ℃ than the UVWPU without using HTPS modified, and the adhesion and pencil hardness are also improved.

Abstract:A new degradation method for crystal violet (CV) from wastewater was proposed without adding any oxidant. The microwave catalyst of MgFe2O4-Fe2O3 was obtained through co-precipitation crystallization method, and its degradation performance for the wastewater containing CV was systematically evaluated under microwave irradiation, including catalyst dosage, microwave power and irradiation time. The results indicated that microwave catalyst MgFe2O4-Fe2O3 displayes excellent catalytic activity, and degradation efficiency for CV from a 200 mg/L wastewater can be highly up to 99.3% with microwave power of 800 W, catalyst dosage of 1 g/L, and irradiation time of 5 min. In addition, the mechanism for the microwave catalytic oxidation degradation was preliminary discussed, and hydroxyl radical (·OH) generated during the catalytic reaction acted as the dominant oxidant for the degradation, demonstrating from the experiment of adding different oxides as removal agents. Under microwave irradiation, microwave catalyst can effectively absorb electromagnetic wave to produce photo-electric effects with generation of electron-hole pairs (e-cb+h+vb), which will react with H2O molecules to produce ·OH, and then the formed ·OH groups oxidation can degrade the organic compounds existing in wastewater. The proposed microwave catalytic oxidation degradation is a new method for highly efficient degradation of organic wastewater.

Abstract:An endophytic actinomycete strain OsiSh-10 significantly against rice blast pathogens was successfully isolated from Xiangaizao 7 rice (Oryza indica) of Liuyang Dawei Mountain in Hunan Province. The control effects of OsiSh-10 on leaf blast in field were investigated by coating seeds and spraying leaf of rice with it, which were as follows: leaf blast was controlled by spraying OsiSh-10 on leaf of rice , but coated seeds with OsiSh-10 unworked for leaf blast. According to its morphological features, culture characteristics, physiological and biochemical characteristics, 16s rRNA gene sequence comparison, and phylogenetic tree construction analysis, OsiSh-10 strain was classified as Streptomyces albus. OsiSh-10 strain is a promising biocontrol actinomycete for rice blast.

Abstract:To discover the function of CONSTANS-LIKE 7 (COL7) in regulating plant flowering, we used qPCR, GUS staining, et al, to study the light and circadian regulating the expression of COL7, and COL7 regulating Arabidopsis flowering time. The results showed that COL7 was regulated by light and circadian, and the overexpressing COL7 transgenic lines inhibited Arabidopsis flowering time under long-day (LD) condition through down-regulating CONSTANS (CO) and FLOWERING LOCUS T (FT), and the col7 mutant had no obvious flowering phenotype under LD or SD conditions. So COL7 may have redundant functions with other CONSTANS-LIKEs (COLs) in controlling the flowering time of Arabidopsis.

Abstract:According to the factors affecting the diameter size (i.e. mass flow rate, pipeline length and pressure drop), this article analyzed the pipeline design model of Rubin from the three aspects and established their corresponding numerical models. Furthermore, the reliabilities of the proposed numerical models were validated by another pipeline design model (i.e. the MIT model). Besides, the economic cost of CO2 pipeline transportation was also estimated through the cost analysis of the total pipeline capital investment and the additional pressure station cost. The research result shows that: (i) the proposed models share the same variable change rules and numerical model types with the validation model, and (ii) all of them have high correlation with numerical models (their correlation coefficients R2 are larger than 0.970). The pipeline design and cost analysis proposed in this work have some reference value for the process design of CO2 pipeline transportation.

Abstract:To explore the impact of different transcription factor FOXM1 isoforms in breast cancer EMT process, the eukaryotic expression plasmids for two FOXM1 isoforms, FOXM1B-EGFP and FOXM1C-EGFP, were constructed and transfected into breast cancer cells. The expression levels of FOXM1 isoforms and EMT related genes in the cells were detected with RT-PCR and Western blot. The migration ability of the cells overexpressing the FOXM1 isoforms was measured with the transwell test. The FOXM1B-EGFP and FOXM1C-EGFP eukaryotic expression plasmids were successfully constructed. We found that the levels of exogenous FOXM1B in mesenchymal cells were higher than those in epithelial cells, and it was mainly located in the nucleus. The high levels of FOXM1B expression significantly stimulated the invasion of breast cancer cells and EMT process. The levels of exogenous FOXM1C in epithelial cells were higher than those in mesenchymal cells, and they were expressed in both the nucleus and the cytoplasm. The high levels of FOXM1C expression inhibited the invasion of breast cancer cells and EMT process. FOXM1B was located mainly in the nucleus of cells and FOXM1C was expressed in both the nucleus and the cytoplasm of cells. The research has indicated that FOXM1B and FOXM1C play different roles in the process of EMT of breast cancer cells.

Abstract:A new kind of three-component nanomaterials-In2S3-Ag/TiO2 nanotube arrays was first synthesized in two-step deposition method. In this study, the morphology, elements, crystal structure and photoelectric property testing of the three-component photocatalyst were characterized by scanning electron microscope (SEM) and fluorescence photoluminescence spectra (PL), etc. The three-component photocatalyst was applied to the photodegradation 2,4-dichlorophenoxyacetic acetic acid (2,4-D). The photocatalytic degradation experiment results of 2,4-D have shown that its 100% removal rate can be achieved within 140 minutes. The unique two-step excitation process in the three-component In2S3-Ag/TiO2NTs system leads to the significant improvement of photocatalytic ability. The experiments indicate that different values of pH and the concentration of 2,4-D have significant effect on degradation. The preliminary results show that the photocatalytic reactions are optimized at pH 4.23, higher or lower pH levels will reduce the removal rate due to the phase change of 2,4-D molecules. The photocatalytic degradation mechanism was also analyzed with equations and model diagrams.

Abstract:Plots were set up in typical hilly red soil region field (conventional tillage, CT and no tillage, NT) of central Hunan province. Simulated rainfall experiments were conducted to modify the built linear regression model in which the variable was the runoff rate of sediment delivery by runoff, and then, the model of SOC loss was established on the basis of the revised model and SOC enrichment characteristics of sediment. The results showed that the model of SOC loss could be effectively adapted to the simulation of SOC loss in hilly red soil region of central Hunan province during a rainfall event and could get a wonderful simulation result and accuracy. The mean error from the simulation of SOC loss rate was observed to be around 30% with the determination coefficient beyond 0.85 in CT and NT. In the meantime, the simulated results indicated that the process of the sediment and SOC loss revealed a fluctuant state under overland flow erosion. The sediment and SOC loss rate rose at the first stage of 0~10 min after runoff began and then kept a relatively stable tendency. Comparing the model of sediment transport by runoff and SOC loss in NT with that in CT,the results demonstrated that the sediment and SOC loss rate in CT were greater than that in NT under erosive rainfall. And the situation of sediment and SOC loss in CT were similar to that in NT under non-erosive rainfall.

Abstract:Iron-carbon microelectrolysis with Fenton process was used to pretreat the mature landfill leachate and to enhance its biodegradability.The factors, such as initial pH, iron-carbon concentration, the mass ratio of iron to carbon, dosage of H2O2 and reaction time were investigated. Under the optimal conditions of initial pH of 3, iron-carbon concentration of 52 g/L, iron to carbon mass ratio of 3, H2O2 dosage of 12ml/L, the removal efficiency of COD reached 75% after a reaction time of 1 h. The ratio of BOD5 to COD also increased from 0.075 to 0.250, which suggested that iron-carbon microelectrolysis with Fenton process could significantly improve the biodegradability of landfill leachate, compared with the single iron-carbon microelectrolysis or Fenton process.

Abstract:With the acceleration of new-type urbanization, how to realize the coordinated development between urbanization and eco-environment will be the central topic of the development of Yangtze River Economic Zone. 36 cities in the Yangtze River Economic Zone were studied, three indices were selected to build an eco-environment health evaluation system, including the pressure, status and restoration potential of ecological environment. An entropy-comprehensive evaluation model was established to comprehensively assess the eco-environment health of each city. The results indicate that the eco-environment level of 36 cities in the Yangtze River Economic Zone has obvious spatial difference, and the synthetic index of environment of the cities on the lower reaches of the Yangtze River is higher than those on the middle and upper reaches. According to the differences of various eco-environment indices of 36 cities in the Yangtze River Economic Zone, the 36 cities are divided into six types with the PCA ordination. Finally, the study analyzed the relationship between urbanization and the pressure, status, restoration potential of ecological environment to understand the eco-environment level differences of 36 cities in the Yangtze River Economic Zone under the background of urbanization with the correlation analysis method. The results show that urbanization and the eco-environment pressure exhibit exponential curve and the coupling characteristics of urbanization and eco-environment of cities on the upper, middle and lower reaches of the Yangtze River are different.