Abstract:Three pre-aging treatments of natural aging, artificial under-aging and artificial peak-aging were chosen to systematically investigate the influence of pre-aging on the corrosion resistance and microstructure of an Al-1.0Mg-0.5Si-0.8Cu alloy produced by combined cold-rolling and aging process using hardness measurement, intergranular corrosion test, slow strain rate technique, and transmission electron microscopy （TEM）. The results show that pre-aging can tune the hardness and corrosion resistance of the alloy. Among the three pre-aging treatments, the artificial peak-aging treatment results in the optimal combination of hardness（being 159 HV） and corrosion resistance（with the maximum intergranular corrosion depth of 55 μm and the stress corrosion cracking susceptibility index Iδ of 8.3%）. The TEM results reveal that the high density of dislocations efficiently enhances the hardness of the alloy. Numerous nano-sized Cu-rich lath-like Q" precipitates or curved continuous precipitates are distributed in the matrix, which eliminate the formation of grain boundary precipitates and greatly reduce the electrochemical potential difference between the matrix and PFZ，consequently significantly improving the corrosion resistance of the alloy. In the alloys pre-aged by natural aging, artificial under-aging and artificial peak-aging, the degree of precipitation in the matrix increases in sequence, so that the electrochemical potential difference between the matrix and PFZ decreases in sequence. Therefore, the corrosion resistance of the alloy is improved in sequence.

Abstract:The effects of different Cd contents on the microstructure and mechanical properties of Al-Cu alloy were studied through mechanical properties testing as well as SEM，EDX and TEM. The results show that the alloys with different Cd content have the similar aging response law in artificial aging process at 175 °C. Cd element can promote the precipitation of strengthening phase θ' of Al-Cu alloys. The time for peak aging of 0.19% Cd alloy and 0.36% Cd alloy was shortened and the peak hardness value was obtained upgrade. In the peak aging state, when the Cd element mass-fraction increased from 0.10% to 0.19%, the alloy yield strength increased from 384.2 MPa to 422.8 MPa, and the elongation decreased from 8.5% to 7.1%, but the yield strength did not change and the elongation decreased to 5.86% when the mass-fraction of Cd was 0.36%. TEM shows that the number of precipitated phases in the 0.19% Cd alloy was large and the size was small, so that the precipitation strengthening effect of the alloy was more obvious; the length of precipitated phases in the 0.36wt.% Cd alloy became slightly shorter, and the increase of the number was not obvious. At the same time, there was Cd-rich intercrystalline residual phase on the fracture surface of the alloy containing 0.19wt.% and 0.36wt.% Cd, which was harmful for improving the properties of Al-Cu alloy.

Abstract:This study focused on the inner correlation between heat treatment, microstructure and mechanical property of TNM （Ti-Al-Nb-Mo） alloy. The samples were firstly annealed at 1 270 ℃，then kept at 800 ℃ for 500， 1 000 and 2 000 hours，separately. Using X-ray diffraction（XRD），scanning electron microscope（SEM）， transmission electron microscope（TEM） and microhardness tester，the phases, microstructures and hardness of the samples bared by varied heat treatments were investigated. It was found that the boundaries of（α2+γ） colonies were boarding when the annealing duration increased；more βo and γ particles precipitated at colony boundaries and formed a cellular structure. At the same time, more nano-scaled βo particles were showed up in the single α2 lamellae，inducing α2 /βo /α2 structure and more interfaces. Therefore，the hardness of TNM alloy can be enhanced with the prolonging of annealing duration due to the bigger hardness of βo particles and α2 /βo interface which can hind dislocation movements additionally.

Abstract:The effect of pre-deformation amount on microstructure and properties of Al-Zn-Mg-Cu aluminum alloy was studied by hardness and electrical conductivity, tensile test, intergranular corrosion and exfoliation corrosion experiments, optical microscopy （OM），scanning electron microscopy（SEM） and transmission electron microscopy（TEM）. The results showed that the strength of the alloys with the increase of deformation amount first increased and then decreased under the same ageing heat treatment. The tensile strength and yield strength of the alloy with pre-deformation amount of 5.8% was 577.8 MPa and 549.8 MPa，respectively, which was increased by 25.7% and 20.8%，respectively，when compared with those without pre-deformation. The corrosion resistance was improved with the increase of pre-deformation. The precipitates became the larger discontinuous distribution grain boundary one and the width of the precipitate free zone became wider，which were attributed to the pre-deformation resulting in a large number of dislocation and benefit for precipitation under re-ageing．

Abstract:Carbon fiber was pre-oxidized and desized, and then mixed with mesophase pitch toluene solution. Carbon fiber membrane skeleton was prepared by vacuum assisted flow-filtration，and secondary filtration graphite oxide was filled between carbon skeletons. A self-supporting G-CF-MP composite film with a three-dimensional network structure was obtained after heat treatment. The effects of different heat treatment temperatures of carbonation and graphitization on the morphology，electrical conductivity，and thermal conductivity of the thin film materials were explored and analyzed. Through structural characterization，it is found that carbon fibers form a carbon skeleton with high mechanical properties. Carbon fiber surfaces and the spaces between the fibers are evenly coated and filled with graphene. The mesophase pitch exhibits fluidity and viscosity after reaching the softening point and then fully wets the gap between carbon fiber and graphene. The three carbon materials act synergistically to obtain a high mechanical strength and high conductivity G-CF-MP composite film material. Conductivity test found that graphitization can effectively improve the conductivity of the material. The square resistance of G-CF-MP composite film after carbonization at 900 ℃ is 2.853 Ω/sq，and the square resistance after graphitization is 0.229 Ω/sq. The thermal conductivity test results show that the thermal conductivity of G-CF-MP（900 ℃） is 475.2 W/（m·K），and the thermal conductivity of G-CF-MP（2 300 ℃） is 532.8 W/（m·K）.

Abstract:In order to describe the two-phase coupling flow process of paint deposition on spherical surface, the Euler-Lagrange method was used to establish the model of paint deposition on spherical surface, including continuous phase model, discrete phase model as well as impinging and sticking model. Polyhedral mesh and SIMPLE algorithm were used to solve this model. According to the results of numerical simulation, the spray flow field of paint deposition on spherical surface and flat almost has the same form in the diffusion zone, but in the paint-deposition zone, the gas phase velocity and the coverage of the spray flow field on spherical surface are larger than those on flat. The main source for forming the paint film is large-diameter particles and medium-diameter particles in the spray flow field. The shape of paint films on the spherical surface is a spherical surface, of which the projection on axial direction is an oval, while it is an oval on flat, and the film thickness decreases along the elliptical radial direction. By comparison, the film thickness on spherical surface is thinner than that on flat, and the coverage of film distribution and the painting rate on spherical surface are smaller than those on flat. However, the uniformity of paint film on spherical surface is better than that on flat. As the diameter of spherical surface increases, the coverage of film distribution and the uniformity of film thickness increase，and the film thickness and the painting rate also increase. The characteristics of paint deposition on spherical surface were verified by experiments.

Abstract:In view of the mixed aggregate filling mine，in order to determine the optimum proportion of filling slurry, firstly，the physicochemical properties of filling materials were analyzed. Based on the theory of Talbol grading and the theory of maximum bulk density，the ratio of rod grinding sand and waste rock was determined. 13 groups of tests were designed with BBD response surface method（RSM-BBD） to analyze the effects of slurry mass fraction, cement-aggregate ratio and mixture aggregate ratio on the strength of filling body. Finally，the response surface model was constructed with the intensity of each age as the response value to study the correlation between each response parameter and the target response as well as the optimal ratio of the filling slurry under multi-objective conditions. The results show that the strength of the filling body is affected by single factors, and the interaction between the various factors has a great influence on the filling body. The interaction between the mass fraction and aggregate ratio plays a decisive role in the early strength of the filling body. The interaction between the cement-aggregate ratio and aggregate ratio has a significant effect on the medium strength of the filling body. The late strength of the backfill is greatly affected by the interaction of the mass fraction and cement-aggregate ratio. The optimization is based on the lowest unit filling cost, and the optimal ratio is as follow: slurry mass fraction is 80%, cement-aggregate is 1 ∶ 6，the ratio of rod grinding sand and waste rock is 3 ∶ 7，and the test is verified to meet Jinchuan Mine strength requirements.

Abstract:Polyurethane prepolymers were synthesized from poly (caprolactone) diol (PCL-2000) and isophorone diisocyanate（IPDI）. With a chain extension polymerization of polyurethane prepolymers, piperazine and epoxy resin E-44, and by controlling the material ratio of copolymers to adjust the molecular weight and flexibility of synthetic resin，a series of linear multi-block macromolecular resin can be made. With its neutralization hydration effect, new cationic waterborne resin can be obtained. The design idea of the experiment was introduced in detail. The effect of material ratio on the resin structure parameters, properties of waterborne resins and cured products was explored. The results show that the molecular weight of synthetic resin and the particle size of waterborne resins can be controlled by adjusting the material ratio. The tensile strength, elongation at break, Tg of cured product can be adjusted from 10.46 MPa to 22.14 MPa，629% to 190% and 24.1 ℃ to 44.7 ℃，respectively

Abstract:A kind of UV-absorbing fluorine-silicon acrylic resin was prepared by solution copolymerization with vinyltrimethoxysilane（VTMS），hexafluorobutyl methacrylate（HFMA） and 2-（4-Benzoyl-3-hydroxyphenoxy） ethyl acrylate（BHEA） as modifying monomers. The acrylic polymers were characterized by Fourier transform infrared spectrum（FT-IR），Ultraviolet（UV） absorption spectrum；and the coatings thereof were studied by thermogravimetric analysis（TGA），water contact angle（CA） and Xenon lamp artificial accelerated aging tests. The results showed that the resins contained modifying groups and exhibited high UV absorbing performance, and the coatings showed good heat-resistance and hydrophobicity with the water CA of 92°. Meanwhile, the weather-resistance was promoted under the enduring protection of the modifying monomers. After 1 000 h aging test，the color difference and gloss retention of coatings were 3.12 and 80.4%, respectively.

Abstract:A purity certified reference material for Basic Orange II was studied by means of raw material purification, qualitative analysis，quantitative analysis，homogeneity test，stability test，as well as characterization and uncertainty evaluation. The candidate standard substance was prepared by recrystallization of purchased Basic Orange II. The candidates were purified，dried，and then encapsulated in brown glass bottles. The homogeneity and stability of several sample bottles were studied by stratified random sampling. The chemical composition of the candidate reference material of Basic Orange II was confirmed by infrared（IR） spectrum，high resolution mass spectrometry （MS） and proton nuclear magnetic resonance（NMR）. 7 qualified laboratories were cooperated for certification of Basic Orange II. The purity of the product was analyzed by mass balance method （concluding area normalization, water content, ash content and residual solvent analysis by liquid chromatography）. The results showed that the certified value of the purity reference material was 99.2% and the relative expansion uncertainty was 1.0%（k = 2）. The purity reference material was identified as the national grade II certified reference materials，which was numbered GBW（E）100372，and was expected to be used in the calibration of instruments and method evaluation in food and cosmetic analysis.

Abstract:The FT （FLOWERING LOCUS T） overexpression and mutant plants were analyzed by quantitative PCR and physiological assays to further study the effect of FT gene on the plant vegetative growth. The results showed that the FT overexpression lines had shorter and sparser root hairs with abnormal phenotypes such as branch, ballooned and wavy types when compared with the wild type. On the contrary，ft-10 had longer and denser root hairs with normal phenotypes when compared with wild type. Quantitative analysis of the gene expression including KOAJK、SCN1、RHD2、LRL3、RSL4、RHD6 related to root hair initiation elongation showed that the FT overexpression lines were significantly lower than those of the wild type, while ft-10 were slightly higher than those of the wild type. The results indicate that the FT gene plays a negative role in the initial elongation of root hairs and affects the polar growth and quantitative distribution of root hairs. This study promotes the understanding of the FT function in the vegetative growth process，and also lays the foundation in research of the root development mechanism.

Abstract:Cell penetrating peptides are small molecular peptides that can penetrate cell membranes without damaging the structure of cell membranes. These peptides are generally composed of no more than 30 amino acids. Two tumor lineage-homing cell-penetrating peptides labeled with FITC for lung cancer and liver cancer were synthesized and added to different kinds of tumor cells with different concentration gradients. The number of cells containing fluorescence was detected. The results approved that the two kinds of cell-penetrating peptides showed different cell selectivity. The fluorescence specificity of CPP33 was strong at the concentration of 10 μmol/L. The number of cells containing fluorescence was about 50% by Flow cytometer. The fluorescence specificity of CPP44 was strong at the concentration of 10 μmol/L. The number of cells containing fluorescence was about 60% by Flow cytometer. Moreover, the number of cells containing fluorescence increased with the increase of concentration, respectively. In conclusion, these tumor lineage-homing cell-penetrating peptides may provide a new method for precise delivery of anticancer molecules in vivo.

Abstract:After NDV infects the liver tumour cell，USP18 （Ubiquitin Specific Protease 18） acts as a deubiquitin enzyme and cleaves ubiquitin from ubiquitinated protein substrates. NDV infection of liver tumour cell can induce the apoptosis of cancer cells. Infection with NDV up-regulates the expression of USP18，and the role of USP18 in the apoptosis induced by NDV was investigated. In this study, the liver tumour cell line Huh7 is taken as the system, and western blot and qualitative PCR are considered. It is found that USP18 promotes the apoptosis of cancer cells induced by NDV，which demonstrates that USP18 has the anticancer function. In contrast, knock-down of USP18 inhibits the apoptosis of the cancer cells, which reveals that USP18 can positively regulate the protein level of Bax and NOXA. Consistently，overexpression of USP18 enhances the permeability of mitochondrial membrane and promotes the release of CYTOCHROME C. Similarly, overexpression of USP18 increases the cleaved caspase-7 and strengthens the apoptosis as well. It is also found that USP18 can upregulate the protein level of ISG12a（IFN-stimulated gene 12a）. It attenuates the ubiquitination degradation of ISG12a. The findings in this research provide a profound influence and a new insight towards treatment for liver cancer.

Abstract:This research mainly used the electrostatic interaction and self-assembly of surfactant to induce the formation of CTAB-PdNPs aggregation. The results showed that the electrostatic interaction between the cationic surfactant and anionic Pd precursor can shield the electrostatic repulsion between the hydrophilic groups of CTA+. It drives the formation of CTAB-PdNPs aggregation on the molecular level. This study chose p-CNB as target pollutant and its catalytic reduction as probe, showing that CTAB-PdNPs have high catalytic activity and dehalogenation ability which can convert p-CNB into aniline in 90 minutes. Besides, this study further investigated the effect of Pd dosages，CTAB concentration, initial pH and NaBH4 dosages on the catalytic reduction. The optimum conditions were Pd dosage value of 0.125 mmol/L，CTAB concentration value of 1.0 mmol/L，initial pH value of 5 and NaBH4 dosage value of 15 mmol/L. The dechlorination efficiency of p-CNB can reach up to 81.9% after eight times recycle tests，which proves the aggregation has an outstanding catalytic stability. Above all，this study not only reports a new method of synthesizing PdNPs assembly with special regular shapes，but also provides a feasible technology for the removal of micro-pollutants in the environment.

Abstract:Active chlorine（chlorine and hypochlorite） was generated with NaCl electrolytes by mixed metal oxide（IrO2-Ta2O5/Ti） electrode to inactivate Microcystis aeruginosa. The generation of active chlorine abides by the Faraday's law, and its concentration is proportional to the applied current density and reaction time. The variation of integrity, surface morphology, and photosynthetic ability of Microcystis aeruginosa during the electrochemical oxidation processes（EOPs） were investigated, and the release and degradation of algal organic matters and microcystins （MC-LR） were also studied. The results indicat that the EOPs can effectively inactivate Microcystis aeruginosa, and the proportion of cell lysis increases with current density and reaction time. The concentration of extracellular MC-LR during the EOPs increased and then decreased to below 1.0 μg·L-1. The EOPs can not only inactivate Microcystis aeruginosa，but also control the concentrations of algal organic matters and MC-LR. Therefore，the EOPs have a promising application potential for treating algae-laden water.

Abstract:Taking the municipal sludge as the remediation objects and aiming at studying the effects of electrokinetic remediation of heavy metals from municipal sludge，model tests were carried out with different reagents，which were sophorolipid, rhamnolipid，saponin and composite reagents of biosurfactants and citric acid. Current density and heavy metal concentration in discharge liquid and sludge were examined and analyzed in order to explore the mechanism of reagents from the perspective of microstructure. The results demonstrated that the migration of heavy metals was mainly in the sludge and the concentration of heavy metals was very low in the discharge liquid. Best treatment was achieved around anode area and then followed by the cathode region, while heavy metals were accumulated in middle region. By comparing the removal effect of four biosurfactants, the highest removal rates of Zn，Cu，Ni and Cd were sophorolipid（53.85%），rhamnolipid（44.26%），rhamnolipid（56.33%） and sophorolipid（34.43%），respectively in anode region. Citric acid promoted the migration of heavy metals significantly in middle region, so that the removal rate with composite reagents of biosurfactants and citric acid were increased by 0.90%~16.08%. Based on the test results，it is recommended to apply sophorolipid or composite reagents with citric acid for high concentration of Zn and Cd in sludge treatment. As for high concentration of Cu and Ni, rhamnolipid or composite reagents with citric acid is a better choice.

Abstract:In the process of identifying groundwater pollution sources，a monitoring well optimization method based on Bayesian formula and information entropy is proposed for the problem that the monitoring value of monitoring wells is insufficient or the correlation between monitoring values and model parameters is weak. The two-dimensional groundwater contaminant transport model was numerically solved by GMS software. To reduce the computational load of the numerical model repeatedly in the optimization design of the monitoring wells and the identification process of the pollution source, the Kriging method was used to establish the surrogate model of the numerical model. As an optimization index, the optimal monitoring schemes of different monitoring types were selected, and the monitoring cost and inversion accuracy were taken as reference factors for the corresponding monitoring schemes. Then, the differential evolution adaptive Metropolis algorithm was used to identify the pollution source. The case study results show that: The determination coefficient of the Kriging surrogate models of the 7 monitoring wells was greater than 0.98, which indicated that the Kriging surrogate models can well replace the original numerical model. The scheme 1（single well No. 3） based on the lowest monitoring cost has an information entropy of 12.772；The scheme 2 （the combination of well No.2 and No.3） taking the monitoring cost and inversion accuracy into account has an information entropy of 9.723；The scheme 3（the combination of well No.2，3 and 5） with higher inversion precision has an information entropy of 9.377. Both the posterior distribution ranges and the standard deviation of model parameters from scheme 1 to scheme 3 were gradually reduced, which verifies that the information entropy is an effective measure of the uncertainty of the posterior distribution of the parameters.

Abstract:In this study, the mass concentrations of inorganic elements in PM2.5 of Chenzhou city were determined by using inductively coupled plasma mass spectrometry（ICP-MS），and their sources were analyzed by the enrichment factor and principal component analysis. The results showed that the average mass concentration of PM2.5 in the study area were 28.7 μg·m-3，30.7 μg·m-3，41.4 μg·m-3 and 58.1 μg·m-3 in the spring, summer, autumn and winter, respectively. The average proportion of inorganic elements was 15.63% of PM2.5，of which Al，Fe，Zn，Cu， Pb，Cr，Mn，As，Si and Ti accounted for 90.6% of the total amount of inorganic elements. The enrichment factor analysis showed that Cd，Ag，Bi，Sb，As，Cu，Pb，Zn，Cr，Ni and V were mainly originated from anthropogenic factor. Particularly，the enrichment degree of non-ferrous metals was higher, which was related to the fact that Chenzhou is a famous town of non-ferrous metals, and the exploitation and smelting of non-ferrous metals are well developed. Principal component analysis showed that the inorganic elements in PM2.5 of Chenzhou city were mainly derived from the combustion of coal and petroleum, automobile exhaust emissions, smelting of non-ferrous metals and soil dust.