Polyaniline/CoRExFe2−xO4 (RE=La, Ce, Y, x=0.05–0.25) nanocomposites were successfully synthesized by a novel coordination-oxidative polymerization-hydrothermal method, and doped by sulfosalicylic acid. The resultant nanocomposites were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM) and electromagnetic measurements. The composites mainly showed nanofibers with a diameter of ca. 70nm and a length longer than 2μm. The surface of composites was uniformly covered with numerous nanoparticles with an average size of ca. 10–20nm. Microwave absorption properties of polyaniline/CoRExFe2−xO4 nanocomposites doped with La ion were found to be better than those doped with Ce and Y ions. For the polyaniline/CoLaxFe2−xO4 nanocomposite, the optimal microwave absorption performance is at x=0.15, that is, the mass ratio of La in CoLaxFe2−xO4 is 7.5%, with the conductivity of the composite about 0.833S/cm. Furthermore, when the layer thickness is 2mm, the maximum reflection loss achieves the maximum number of −42.65dB at 15.91GHz with a bandwidth of 6.14GHz above −10dB loss, suggesting that these nanocomposites are excellent in microwave absorbing capacity.

Polyaniline/CoFe2 O4 binary nano-composites were prepared by coordination-oxidative polymeriza-tion-hydrothermal method, and doped by sulfosalicylic acid. The influence of reactants ratio and concentration of doping acid on electromagnetic properties of resulting composites was investigated. The micrographs, struc-ture and electromagnetic properties of polyaniline/CoFe2 O4 composites were characterized by TEM, XRD, FTIR and electromagnetic measurements. The results indicate that the prepared composite show a multi-level structure in which CoFe2 O4 is cube-shaped with an average particle size less than 20 nm. The optimal experi-mental results were as follows: the conductivity of the composite is about 0.43 S/cm when the content of CoFe2 O4 in composite is 8.86%( mass fraction) . When the thickness of PAn/CoFe2O4 composite is at 2 mm, a maximum reflection loss of -16.71 dB at 16.01 GHz is observed with a bandwidth of 4.68 GHz above -10 dB loss; and when the thickness of PAn/CoFe2O4 composite is at 3.2 mm, a maximum reflection loss of-51.81 dB at 9.23 GHz is observed with a bandwidth of 3.69 GHz above -10 dB loss. The nanocomposite exhibits excellent microwave absorbing capacity.

Lintong-Chang'an fracture zone and its relationship with earth fissures are briefly represented and it is testified in this paper that there exists earth fissures in the fracture zone based on two stratigraphic sections located in Lintong-Chang'an fracture zone.The result shows that the earth fissure developed into fracture zone has the same attribute as that of earth fissure upon hanging wall of Lintong-Chang'an fault.Also,the characteristics of the earth fissure and its activity law are analyzed on the basis of faulted bedding plane and the thickness variation of the same formation.It shows that the activity of earth fissure developed into Lintong-Chang'an fracture zone is varied in different sector:the western is relatively weak but the eastern strong,which is consistent with the fault's activity.

The aim of this study is to investigate the effect of KGF (Keratinocyte growth factor) gene therapy mediated by the attenuated Salmonella typhimurium Ty21a on radiation-induced pulmonary injury in rats model. Sprague-Dawley rats were divided into three groups: TPK group (treated with TPK strain, attenuated Salmonella typhimurium Ty21a-recombined human KGF gene); TP group (treated with TP strain, attenuated Salmonella typhimurium Ty21a-recombined blank plasmid); and Saline group (treated with saline). After intraperitoneal administration for 48 h, the thoraxes of the rats were exposed to X-ray (20 Gy), and the rats were administered again two weeks after radiation. On the 3rd, 5th, 7th, 14th and 28th day after radiation, the rats were sacrificed and lung tissues were harvested. Histological analysis was performed, MDA contents and SOD activity were detected, mRNA levels of KGF, TGF-β, SP-A and SP-C were measured by Real-time RT-PCR, and their concentrations in the BALF were quantified with ELISA. Administration of TPK strain improved the pathological changes of the lung on the 28th day. In the TPK group, KGF effectively expressed since the 3rd day, MDA contents decreased and SOD activity increased significantly, on the 7th day and 14th day respectively. SP-A and SP-C expression elevated, whereas TGF-β expression was inhibited in the TPK group. These results suggest that this novel gene therapy of KGF could ameliorate radiation-induced pulmonary injury in rats, and may be a promising therapy for the treatment of radiative pulmonary injury.

Objective To explore the toxic effect of lead acetate on human renal mesangial cells (HRMC).Methods After the treatment of HRMC with 10,20μmol/L lead acetate for 24 h,HE staining was applied to observe the morphological changes of these cells.The expression levels of p53,bax,bcl-2 were detected with immunohistochemical method.The rate of apoptosis was measured by stain and flow cytometry.Results Morphological changes of apoptosis in HRMC were observed in the treated group.Immunohistochemical analysis indicated that the expression of p53 and bax was increased while the expression of bcl-2 was decreased by the treatment.The flow cytometry and stain results showed the higher induced cell apoptosis rate in the treated group than that in the control group.Conclusion Lead acetate can remarkably inhibit human renal mesangial cells growth,promote apoptosis,and affect the kidney.

[Objective]To investigate the effect of lead acetate on apoptosis and activity of Caspase-3 in human femoral artery endothelial cells(HFAEC).[Methods]After treated with lead acetate,Hoechst 33258 staining was applied to observe the morphological changes of HFAEC,and the expression level of caspase-3,P53,Bax and Bcl-2 was detected with immunohistochemical method.The rate of apoptosis was measured by the flow cytometry.[Results]After treated with 10 μmol/L lead acetate 24 h and 48 h,Hochest 33258-PI staining showed morphological changes in lead acetate group.Immunohistochemical analysis on artery endothelial cells indicated that the expression of Caspase-3,P53 and Bax was increased while the expression of Bcl-2 was decreased by the treatment.The flow cytometry results showed cell apoptosis rate of the lead acetate group was higher than that of the control group(P0.05).[Conclusion]Lead acetate can induce apoptosis in HFAEC with a possible mechanism,which may be related to the activation of Caspase-3.

Objective To study lead acetate induced apoptosis of mice astrocytes C8 and provide theoretical criteria for the damage of lead to blood-brain barrier.Methods Mice astrocytes C8 in logarithmic growth phase were exposed to different concentration of lead acetate(0,5,10,20,and 40μmol/L) for different time periods(6,12,24,and 48 h).Proliferation of cells was detected by MTT.Cell morphology was observed by inverted phase contrast microscope.Spectrophotometer was used to detect the cell damage level,LDH activity and MDA content in cellular supernatant.The expressions of P53,Bax and Bcl-2 were detected by immunohistochemistry.Cell apoptosis rate was detected by PI-Hoechst33342 stain and flow cytometry. Results Under different concentrations of lead acetate with different treatment time periods,the cell growth activities in treated groups reduced significantly compared to the control group(P0.01) showing concentration and time-dependent relationship.Morphological observation of the group treated with lead acetate(5,and 10μmol/L) for 24h showed that cell density lowered,synapses became shorter and thinner and the intercellular junction reduced compared to control group.LDH and MDA contents in supernatant of toxicant groups increased significantly compared to control group(P0.01).The results of immunohistochemistry showed that the expression of P53 and Bax increased,while that of Bcl-2 decreased. PI-Hoechst33342 double staining and flow cytometry demonstrated that cell apoptosis rate of treated groups increased significantly compared to control group.Conclusions Lead acetate is able to inhibit mice astrocytes growth and accelerate the apoptosis by raising the Bax/Bcl-2 rate value,and finally damages the blood-brain barrier.

为探讨乙酸铅对人星形胶质细胞超微结构及凋亡相关蛋白天冬氨酸特异性半胱氨酸蛋白酶-3(Caspase-3)表达的影响,将处于对数生长期人星形胶质细胞(细胞密度约5×103个/ml)分别暴露于0(对照)、10、20μmol/L乙酸铅,培养24 h后,采用倒置相差显微镜观察细胞的形态学变化,采用透射电镜观察细胞超微结构的变化,采用流式细胞仪检测细胞凋亡率,采用细胞免疫化学法检测Caspase-3的表达,采用Western blot法检测细胞中Caspase-3表达量。结果显示,显微镜下观察发现,乙酸铅染毒人星形胶质细胞变小、变圆,细胞间隙变大,细胞部分脱落。透射电镜观察发现,乙酸铅染毒细胞胞质内出现空泡,核固缩,核膜结构模糊,线粒体数目减少、空泡化。流式细胞仪检测结果表明,乙酸铅染毒组细胞凋亡率高于对照组,差异有统计学意义(P<0.05)。细胞免疫化学法和Western Blot法检测结果显示,乙酸铅染毒人星形胶质细胞Caspase-3表达量均高于对照组,并且表达量随着染铅剂量增加而升高。提示乙酸铅可诱发人星形胶质细胞凋亡,其机制可能与Capase-3的活化有关。

[Objective] To investigate the toxic effect of lead acetate on in vitro cultured cortical neurons of rats.[Methods]Primary cultured cortical neurons of newborn rats were treated with different concentration of lead acetate (50,100 and 200 μg/ml). Neutral red stain and PI-Hoechst 33342 double stain were used to compare the viability of cortex neurons, which were cultured in the medium containing different concentration of lead acetate for 6 hours, 12 hours, 24 hours and 48 hours respectively.[Results]PI-Hoechst 33 342 double staining showed pyknosis occurred in some cortical neurons and that increased with the increase of the dose of lead acetate and culture time, the cortical neurons with red fluorescent and apoptosis increased, after 12 hours of lead acetate exposure. Apoptotic rate of cortical neurons of control group was significantly lower than that in both medium and high concentration of lead acetate groups (P0.05). Neutral red staining showed time, and the difference was significant between cortical neurons treated with high concentration of lead acetate for 24 and 48 hours and cortical neurons treated for 6 hours, the rest was not significantly different (P0.05). The viability of cortical neurons treated with different concentration of lead acetate decreased with the increase of lead acetate dose, especially for the high and low concentration of lead acetate groups, the difference was significant (P0.05).[Conclusion]The viability of cortical neurons treated with high, medium and high concentration of lead acetate for 12 hours is significantly lower than that of control group, and shows dose-and time-dependent relationship.

The execution method of geological hazard evaluation report and the results of the state-of-art evaluation,forecast evaluation and comprehensive evaluation on the geological hazards of No.3 line of Guangzhou MRT system are presented in this paper on basis of the relative government documents.Then prevention and treatment measures for geological hazards are proposed in detail,clear evaluation results are achieved and engineering countermeasures are recommended.This paper has guidance significance for the design and construction of No.3 line of Guangzhou MRT system and has reference significance for similar geological hazard evaluations in the future.

本文介绍了广州市轨道交通六号线主线地质发育特点。主要从工程地质条件的角度,分段对线路施工工法的选择等提出了建议。

Taking the special physical exploration of Tianmei fault for Guangzhou metro line nine for an example,the superiority characteristics of physical exploration have been discussed.These superiority features are embodied on many aspects,such as finding out the position and characteristics of the fault;investigating the spatial position between fault structural and tunnel;studying the rock character and hydrogeological characteristics of the fault;prediction the engineering problems which may encounter during the excavation in fault and putting forward the suggestion of engineering measures.This technology can provide geology foundation for the engineering design and construction.

Objective To explore the toxic effect of lead acetate on renal tubular epithelial cell HK-2. Methods HK-2 cells were treated with 10μmol/L and 20μmol/L lead acetate. After 48 hours,Giemsa and H E stainings were applied to observe the morphological changes of these cells,and expression levels of apoptosis-related genes P53,Bax and Bcl-2 were detected with the immunohistochemical method. The apoptosis rate was measured by flow cytometry. Results Characteristic apoptotic changes of HK-2 cells were observed in the treatment group. Immunohistochemical analysis indicated that expressions of P53 and Bax were increased,while expression of Bcl-2 was decreased after the treatment. Flow cytometry results showed that the cell apoptosis rate was higher in the treatment group than in the control group. Conclusion Lead acetate can remarkably inhibit renal tubular epithelial cell growth,promote apoptosis,and affect the kidney.

Objective To investigate the effects of lead acetate on the ultrastructure and Caspase-3 expression in human femoral artery endothelial cells(HFAECs).Methods The HFAECs were treated with 10 μmol/L and 20 μmol/L lead acetate for 24 hrs and observed for ultra-structure changes with transmission electron microscope.The rate of cell apoptosis was measured by flow cytometry.The expression levels of Caspase-3 were measured with immunohistochemical method as well as western blotting.Results The HFAECs demonstrated chromatin condensation and margination,and nucleoplasmic space enlargement with lead acetate treatment.The typical apoptotic bodies of cells were formed in the 20 μmol/L group.Immunohistochemical analysis indicated that the expression of Caspase-3 was activated by the treatment.Expression of Caspase-3 in the treated group was higher than that in the control group and amount of expression was increasing with lead concentration.The flow cytometry results showed that the higher cell apoptosis rate induced in the treated group than in the control group(P0.05).Conclusion Lead acetate could induce apoptosis through activation of Caspase-3 in HFAECs.

[Objective]To observe the toxic effect of lead acetate on human femoral artery endothelial cells (HFAEC) and astrocytes,and explore the mechanism of lead acetate passing through blood-brain barrier.[Methods]After treated with lead acetate,Giemsa and H.E.staining was applied to observe the morphological changes of these 2 cells,and the expression level of P53,Bax,Bc1-2 were detected with immunohistochemical method.The rate of apoptosis was measured by flow cytometry.[Results]After treated with 10 μmol/L lead acetate for 24 hours,Giemsa and H.E.staining showed that morphological changes of apoptosis cells were observed in the lead acetate group.Immunohistochemical analysis indicated that the positive expression of P53 and Bax increased while the expression of Bc1-2 decreased.The flow cytometry results showed the higher cell apoptosis rate in the treated group than that in the control group.[Conclusion]Lead acetate can damage HFAEC and astrocytes,promote apoptosis,and affect the blood-brain barrier.

The layer and rock character are the key project of the ground bearing capacity and foundation.Based on the technical survey of the geological condition and the prospecting by boring,the layer is divided into nine rock stratum.The physical property and mechanical property of each rock statum are tested.At the same time,the geotechnical engineering conditon is appraisal appraised.Finally,the proper preliminary engineering project is put forward.

The paper analyzed the standards and theories of physical mechanics parameter value selection in the ground level, summarized experiences and lessons on parameter value selection in course of geotechnical engineering investigation of Guangzhou track traffic engineering, and presented the method of parameter value selection. An important significance was presented to unify the methods and standards of parameter value selection in course of geotechnical engineering investigation of Guangzhou track traffic engineering.