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Constitutive model for casting magnesium alloy involving spherical void evolution

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中国有色金属学会会刊：英文版 2008年第A01期18卷 175-179页

作者：陈斌彭向和范镜泓孙士涛 department of Engineering Mechanics College of Resource and Environment ScienceChongqing University

Casting magnesium alloys are highly heterogeneous materials inevitably containing numerous *** voids will evolve during material deformation and markedly affect material behaviors,so it is important to investigate the equation of the void evolution and the constitutive relation involving the void *** assuming the voids in casting magnesium alloys were spherical,the growth equation of the voids was obtained from the incompressibility and continuity conditions of material matrix. Through combining the obtained void-growth equation with the void-nucleation equation relative to the increment of intrinsic-time measure,the evolution equation of the voids was *** introducing the presented void-evolution equation to a nonclassical elastoplastic constitutive equation,a constitutive model involving the void evolution was put *** corresponding numerical algorithm and finite element procedure of the model were developed and applied to the analysis of the elastoplastic response and the porosity change of casting magnesium alloy *** results show satisfactory agreement with those of the corresponding experiments.

关键词：镁合金压铸铸件饱和多孔介质

Synergistic effects of particulate matter(PM_10) and SO_2 on human non-small cell lung cancer A549 via ROS-mediated NF-κB activation

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Journal of environmental Sciences 2015年第5期27卷 146-153页

作者： Yang Yun Rui Gao Huifeng Yue Guangke Li Na Zhu Nan Sang College of environment and resource Research Center of Environment and Health Shanxi University

Since a real atmospheric scenario usually represents a system involving multiple pollutants, air pollution studies typically focused on describing adverse effects associated with exposure to individual pollutants cannot reflect actual health risk. Particulate matter（PM10） and sulfur dioxide（SO2） are two major pollutants derived from coal combustion processes and co-existing in coal-smoke air pollution, but their potentially synergistic toxicity remains elusive thus far. In this study, we investigated the cytotoxic responses of PM10 and SO2, singly and in binary mixtures, using human non-small cell lung cancer A549 cells, followed by clarifying the possible mechanisms for their interaction. The results indicated that the concomitant treatment of PM10 and SO2 at low concentrations led to synergistic injury in terms of cell survival and apoptosis occurrence, while PM10 and SO2 alone at the same concentrations did not cause damage to the cells. Also, radical oxygen species（ROS） production followed by nuclear factor kappa B（NF-κB） activation was involved in the above synergistic cytotoxicity, which was confirmed by the repression of the actions by an ROS inhibitor（NAC）. This implies that assessment of health risk should consider the interactions between ambient PM and gaseous copollutants.

关键词： PM10 SO2 Synergistic toxicity ROS NF-κB

Particulate matter(PM(2.5)) exposure season-dependently induces neuronal apoptosis and synaptic injuries

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Journal of environmental Sciences 2017年第4期29卷 336-345页

作者： Minjun Chen Ben Li Nan Sang College of environment and resource Research Center of Environment and HealthShanxi University

Epidemiological studies have shown that particulate matter 2.5（PM（2.5）） not only increases the incidence of cardiopulmonary illnesses but also relates to the development of neurodegenerative diseases. Considering that PM（2.5）is highly heterogeneous with regional disparity and seasonal variation, we investigated whether PM（2.5）exposure induced neuronal apoptosis and synaptic injuries in a season-dependent manner. The results indicated that PM（2.5）altered the expression of apoptosis-related proteins（mainly bax and bcl-2）, activated caspase-3 and caused neuronal apoptosis. Additionally, PM（2.5）decreased the levels of synaptic structural protein postsynaptic density（PSD-95） and synaptic functional protein N-methyl-D-aspartate（NMDA） receptor subunit（NR2B） expression. These effects occurred in a season-dependent manner, and PM（2.5）collected from the winter showed the strongest changes. Furthermore, the effect was coupled with the inhibition of phosphorylated extracellular signal-regulated kinase 1/2（p-ERK1/2） and phosphorylated c AMP-response element binding protein（p-CREB）. Based on the findings, we analyzed the correlations between the chemical composition of PM（2.5）samples and the biological effects, and confirmed that winter PM（2.5）played a major role in causing neuronal apoptosis and synaptic injuries among different season samples.

关键词： Particulate matter(PM(2.5)) Season-dependent effect Neuronal apoptosis Synaptic injury

Effect of organophosphorus pesticide pollution on soil animals

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Journal of environmental Sciences 2000年第1期12卷 49-58页

作者： Wang, Zhen-Zhong Zhang, You-Mei Guo, Yong-Can Li, Zhong-Wu resource and environment department Hunan Normal University Changsha 410081 China

This paper studied the change in soil animal community in contaminated and irrigated area by organophosphorus pesticide waste water and its mechanism was discussed. The results showed that the species and quantities of soil animals decreased with organophosphorus pesticide pollution degree increasing. The species of soil animals decreased with average and rare population mainly decreasing, while the amount change was associated with that of the dominant population of Acarina, Collembola and Nematoda. Toxicity experiment demonstrated that the respiration intensity of soil animal was restrained obviously by pesticide pollution. After observation of SEM, the effect of pesticide pollution on the earthworm (\%Pheretima robusta)\% stomach intestinal mucosa damage has been observed, which showed the pesticide contamination may damage the earthworms bodies. Ulcerous focus and perforation on stomach mucosa were usually seen. The stomach microvilli appeared atrophic and disordered especially in the bodies of these earthworms growing in seriously polluted soil, bad atrophic phenomena were seen not only on the stomach mucosa microvilli but also on the cilia of the intestinal mucosa which appeared swollen as a spheroid. Under TEM, RER and Golgi compound dilatation, chondrisome swell and ridge disappearance were observed on cells of stomach epithelium mucosa of \%***\% collected from heavy polluted area. By calculation, the safety concentration of earthworm in methamidophos pesticide is 0\^2517 ml/L.

关键词： pesticide pollution soil animal respiration intensity pathological changes LC 50 CLC number: X592 Document code: A

The Hydrochar Characters of Municipal Sewage Sludge Under Different Hydrothermal Temperatures and Durations

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Journal of Integrative Agriculture 2014年第3期13卷 471-482页

作者： ZHANG Jin-hong LIN Qi-mei ZHAO Xiao-rong department of Soil and Water Science College of Resource and Environment China Agricultural University

Innovative measure is a urgent requirement for managing the huge volume of municipal sewage sludge. The hydrothermal carbonation （HTC） shows some potential advantages for using hydrochar as a soil conditioner. The aim of this work was to investigate the properties of hydrochars, by means of the HTC of municipal sewage sludge under different temperatures （190 and 260~C） and reaction hours （1, 6, 12, 18 and 24 h）. The HTC led to the decreases of N, O and H contents by more than 54.6, 37.9 and 10.0%, respectively, and slight changes of C content. The Py-GC-MS analysis showed that a large proportion of fatty acids, in particular hexadecanoic acid, transferred into alkenes, olefins and aromatic compounds. The 13C-NMR and fourier transform infrared spectra （FTIR） confirmed the transformation and changes in chemical structure in which hydrochar contained lower oxygen-containing organic C of O-alkyl, carboxylic and carbonyl C and aliphaticity, but higher aromatic C and aromaticity. The rich hydrophobic functions induced in high positive charges in the charred sludge. The HTC facilitated the pore structure development, proved by higher specific surface area and specific pore volume, with a maximum of 17.30 and 0.83 cm^3 g^-1, respectively. The availabilities of N, P and K markedly reduced during HTC treatment. The activities of most heavy metals were depressed though they accumulated in the hydrochar. Further work is required to investigate the values and risk of the charred sludge amended to soil.

关键词： municipal sewage sludge hydrothermal carbonization hydrochar

Electrochemical corrosion of steel balls in wet grinding

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中国有色金属学会会刊：英文版 2003年第4期13卷 958-962页

作者：谢恒星李松仁李定或 College of resource and environment Engineering School of resources Processing and Bioengineering department of Mineral Engineering

Rest potentials for the steel ball electrode and the pyrite electrode as well as the combination potentials and the galvanic currents developed in the pyrite steel ball couple were measured. The data demonstrate that the galvanic couples are going to form between the pyrite particles and the steel balls when they contact with each other. The initial combination potential and the initial galvanic current of the pyrite ball couple while bubbling with oxygen are greater than those in aeration of air. The combination potential and the galvanic current decrease more quickly with time while bubbling with oxygen than they do in aeration of air. In an experiment of simulating wear differences, a galvanic current, which is smaller than that developed in the pyrite ball couple, exists between two different ball electrodes in wear degree on the surface of them. Under different grinding time conditions, the equivalent corrosion current density calculated from marked ball wear data by applying Faraday’s law correlates well with those estimated from polarization curves of pyrite and ball electrodes, and the former is always greater than the latter.

关键词：磨矿电化学腐蚀钢球球磨机选矿

An improved protein expression system for T3SS genes regulation analysis in Xanthomonas oryzae pv. oryzae

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Journal of Integrative Agriculture 2019年第6期18卷 1189-1198页

作者： XU Jin-bo ZHANG Cui-ping WUNIERBIEKE Mei-li YANG Xiao-fei LI Yi-lang CHEN Xiao-bin CHEN Gong-you ZOU Li-fang department of environment and resource School of Agriculture and BiologyShanghai Jiao Tong University

Xanthomonas oryzea ***(Xoo)is the causal agent of bacterial blight of rice,which is a significant threat to many of rice-growing *** type Ⅲ secretion system(T3SS)is an essential virulence factor in *** of the T3SS is often induced in the host environment or in hrp-inducing medium but is repressed in nutrient-rich *** elucidation of molecular mechanism underlying induction of T3SS genes expression is a very important step to lift the veil on global virulence regulation network in ***,an efficient and reliable genetic tool system is required for detection of the T3SS *** this study,we constructed a protein expression vector pH3-flag based on the backbone of pHM1,a most widely used vector in Xoo strains,especially a model strain *** vector contains a synthesized MCS-FLAG cassette that consists of a multiple cloning site(MCS),containing a modified pUC18 polylinker,and Flag as a C-terminal *** cassette is flanked by transcriptional terminators to eliminate interference of external transcription enabling detection of accurate protein *** evaluated the potential of this expression vector as T3SS proteins detection system and demonstrated it is applicable in the study of T3SS genes expression regulation in *** improved expression system could be very effectively used as a molecular tool in understanding some virulence genes expression and regulation in Xoo and other Xanthomonas spp.

关键词： Xanthomonas oryzae pv.oryzae broad-host range vector expression vector T3SS genes

Selective removal of nickel from iron substrate by non-cyanide strippers

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中国有色金属学会会刊：英文版 2004年第3期14卷 599-602页

作者：李德良吴晓芙王淀佐 J.A.Finch School of resource and environment School of resources Processing and Bioengineering department of Mining and Metallurgical Engineering

A novel nickel stripper using ammonia as the key component was developed to substitute cyanide for removing nickel film from iron substrates. Its compositions are: ammonia 150 g/L, hydrogen peroxide 50 g/L, ammonium chloride 100 g/L, EDTA 7.5 g/L, copper chloride 15 g/L and glucopyrone 1.2 g/L. The optimum operating conditions are: pH 9.511, temperature 4050 ℃ and stripping time 1 h. It shows many advantages over the traditional cyanide stripper including no toxicity, mild operation, lower cost, larger holding capacity, faster stripping rate and good protection for the base metal, and can meet the technical requirements in industry.

关键词：环境友好技术清洁生产镍选择性去除非氰化萃取器环境工程

PM2.5 exposure induces age-dependent hepatic lipid metabolism disorder in female mice

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Journal of environmental Sciences 2020年第3期32卷 227-237页

作者： Ruifeng Yan Tingting Ku Huifeng Yue Guangke Li Nan Sang College of environment and resource Research Center of Environment and HealthShanxi UniversityTaiyuanShanxi 030006China

Particulate matter exposure has been described to elevate the risk of lung and cardiovascular *** increasing number of recent studies have indicated positive correlations between PM2.5(the fraction of airborne particles with an aerodynamic diameter less than2.5 μm) exposure and the risk of liver ***,research on the effects of PM2.5exposure on liver fat synthesis,secretion,and clearance mechanisms under normal diet conditions is limited,and whether these effects are age-dependent is largely *** C57BL/6 mice at different ages(4 weeks(4 w),4 months(4 m),and 10 months(10 m))were treated with 3 mg/kg body weight of PM2.5 every other day for 4 ***,the ultrastructural changes of liver,the expression of genes involved in oxidative damage and lipid metabolism in the liver were *** of hepatic ultrastructure showed more and larger lipid droplets in the livers of 4-week-old and 10-month-old mice exposed to *** analysis showed that PM2.5 exposure increased the expression of genes related to lipid synthesis,but decreased the expression of genes involved in lipid transport and catabolism in the livers of 10-month-old *** findings suggest that exposure to PM2.5 disrupts the normal metabolism of liver lipids and induces lipid accumulation in the liver of female mice in an age-dependent manner,with older mice being more susceptible to PM2.5.

关键词： Fine particulate matter Liver Lipid metabolism Different ages