|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Application of cusp catastrophe theory to reliability analysis of slopes in open-pit mines显示文摘A method of slope reliability analysis was developed by imposing a state equation on the limit equilibrium theory, given the basis of a fixed safety factor technique. Among the many problems of reliability analysis, the most important problem is to find a performance function. We have created a new method of building a limit state equation for planar slip surfaces by applying the mathematical cusp catastrophe theory. This new technique overcomes the defects in the traditional rigid limit equilibrium theory and offers a new way for studying the reliability problem of planar slip surfaces. Consequently, we applied the technique to a case of an open-pit mine and compared our results with that of the traditional approach. From the results we conclude that both methods are essentially consistent, but the reliability index calculated by the traditional model is lower than that from the catastrophic model. The catastrophe model takes into consideration two possible situations of a slope being in the limit equilibrium condition, i.e., it may or may not slip. In the traditional method, however, a slope is definitely considered as slipping when it meets the condition of a limit equilibrium. We conclude that the catastrophe model has more actual and instructive importance compared to the traditional model. | YANG Kun, WANG Tongxu, MA Zhitao Key Laboratory of Mine Disaster Prevention and Control, Shandong University of Science and Technology, Qingdao 266510, China | 2010 | Mining Science and Technology2010，20，1： | 15 |
| 2 | Interactively interfacial reaction of iron-reducing bacterium and goethite for reductive dechlorination of chlorinated organic compounds显示文摘The interactively interfacial reactions between the iron-reducing bacterium (Shewanella decolorationis, S12) and iron oxide (α-FeOOH) were investigated to determine reductive dechlorination transformation of chlorinated organic compounds (chloroform and pentachlorophenol). The results showed that the interactive system of S12+ α-FeOOH exhibited relatively high dechlorination rate. By comparison, the S12 biotic system alone had no obvious dechlorination, and the α-FeOOH abiotic system showed low dechlorination rate. The enhanced dechlorination of chloroform and pentachlorophenol in the interactive system of S12+α-FeOOH was derived from the promoted generation of adsorbed Fe(Ⅱ) by S12. A decrease in redox potential of the Fe(Ⅲ)/Fe(Ⅱ) couple in the interactive reaction system was determined by cyclic voltammetry. Our results will give new insight into interactively interfacial reaction between iron-reducing bacterium and iron oxides for degradation of chlorinated organic compounds under anaerobic condition. | LI XiaoMin LI YongTao LI FangBai ZHOU ShunGui FENG ChunHua LIU TongXu | 2009 | Chinese Science Bulletin2009，54，16： | 11 |
| 3 | Multiple effects of nitrate amendment on the transport, transformation and bioavailability of antimony in a paddy soil-rice plant system显示文摘Nitrate(NO3^(-))is known to be actively involved in the processes of mineralization and heavy metal transformation;however,it is unclear whether and how it affects the bioavailability of antimony(Sb)in paddy soils and subsequent Sb accumulation in rice.Here,the effects of NO3^(-)on Sb transformation in soil-rice system were investigated with pot experiments over the entire growth period.Results demonstrated that NO3^(-)reduced Sb accumulation in brown rice by 15.6%compared to that in the control.After amendment with NO3^(-),the Sb content in rice plants increased initially and then gradually decreased(in roots by 46.1%).During the first 15 days,the soil p H increased,the oxidation of Sb(Ⅲ)and sulfides was promoted,but the reduction of iron oxide minerals was inhibited,resulting in the release of adsorbed and organic-bound Sb from soil.The microbial arsenite-oxidizing marker gene aox B played an important role in Sb(Ⅲ)oxidation.From days 15 to 45,after NO3^(-)was partially consumed,the soil p H decreased,and the reductive dissolution of Fe(Ⅲ)-bearing minerals was enhanced;consequently,iron oxide-bound Sb was transformed into adsorbed and dissolved Sb species.After day 45,NO3^(-)was completely reduced,Sb(V)was evidently reduced to Sb(Ⅲ),and green rust was generated gradually.Thus,the available Sb decreased due to its enhanced affinity for iron oxides.Moreover,NO3^(-)inhibited the reductive dissolution of iron minerals,which ultimately caused low Sb availability.Therefore,NO3^(-)can chemically and biologically reduce the Sb availability in paddy soils and alleviate Sb accumulation inrice.This study provides a potential strategy for decreasing Sb accumulation in rice in the Sb-contaminated sites. | Xiaofeng Zhang Tongxu Liu Fangbai Li Xiaomin Li Yanhong Du Huanyun Yu Xiangqin Wang Chuanpin Liu MiFeng Bing Liao | 2021 | Journal of Environmental Sciences2021，33，2： | 6 |
| 4 | Mesoporous silica decorated with platinum nanoparticles for drug delivery and synergistic electrodynamic-chemotherapy显示文摘Electrodynamic therapy(EDT)is a conceptually new cancer treatment approach recently proposed by our group.During EDT,the electro-driven catalytic reaction would occur on the surface of platinum nanoparticles(PtNPs)to produce reactive oxygen species(ROS)under the direct current(DC)or square-wave alternating current(AC)electric field.To further extend the potential of EDT,we hereby designed mesoporous silica-based nanocomposites decorated with PtNPs and loaded with anticancer drug doxorubicin(DOX)for synergistic electrodynamic-chemotherapy.Such silica-based nanocomposites could enable homogenous killing of large-sized tumors(over 500 mm^3)and realize remarkable tumor destruction efficacy at a relatively low quantity of electricity.To our best knowledge,this is the first study to combine EDT and chemotherapy to develop a synergetic nanoplatform,openning a new dimension for the design of other EDT-based anticancer strategies. | Tongxu Gu Tong Chen Liang Cheng Xiang Li Gaorong Han Zhuang Liu | 2020 | Nano Research2020，13，8： | 4 |
| 5 | Microaerobic Fe (Ⅱ) oxidation coupled to carbon assimilation processes driven by microbes from paddy soil显示文摘Microaerobic Fe(Ⅱ) oxidation process at neutral pH, driven by microbes can couple to carbon assimilation process in iron-rich freshwater and marine environments;however, few studies report such coupled processes in paddy soil of the critical zone in South China. In this study, rhizosphere soil from flooded paddy field was used as the inoculum to enrich the microaerophilic Fe(Ⅱ)-oxidizing bacteria(FeOB) in gradient tubes with different Fe(Ⅱ) substrates(FeS and FeCO_3) and ^(13)C-biocarbonate as inorganic carbon source to track the carbon assimilation. Kinetics of Fe(Ⅱ) oxidation and biomineralization were analyzed, and the composition and abundance of the microbial community were profiled using 16 S rRNA gene-based highthroughput sequencing. Results showed that microbial cell bands were formed 0.5–1.0 cm below the medium surface in the inoculated tubes with Fe(Ⅱ) substances, while no cell band was found in the non-inocula controls. The protein concentrations in the cell bands reached the highest values at 18.7–22.9 mg m^L(-1) on 6 d in the inocula tubes with Fe(Ⅱ) substrates. A plateau of the yields of ^(13)C-biocarbonate incorporation was observed during 6–15 d at 0.44–0.54% and 1.61–1.98% in the inocula tubes with FeS and FeCO_3, respectively. The inocula tube with FeS showed a higher Fe(Ⅱ) oxidation rate of 0.156 mmol L^(-1) d^(-1) than that with FeCO_3(0.106 mmol L^(-1) d^(-1)). Analyses of X-ray diffraction and scanning electron microscopy with energy-dispersive X-ray spectroscopy revealed that amorphous iron oxide was formed on the surface of rod-shaped bacteria after Fe(Ⅱ) oxidation.Relative to the agar only control, the abundances of Clostridium and Pseudogulbenkiania increased in the inocula tube with FeS,while those of Vogesella, Magnetospirillum, Solitalea, and Oxalicibacterium increased in the inocula tube with FeCO_3, all of which might be the potential microaerophilic FeOB in paddy soil. The findings in this study suggest that microbes that couple microaerobic Fe(Ⅱ) oxidation to carbon assimilation existed in the paddy soil, which provides an insight into the iron-carbon coupling transformation under microaerobic conditions in the critical zone of the iron-rich red soil. | Xiaomin LI Shan MOU Yating CHEN Tongxu LIU Jun DONG Fangbai LI | 2019 | Science China Earth Sciences2019，62，11： | 3 |
| 6 | Existence of positive solutions for boundary - value problems of second - order delay differential equations显示文摘 | Ding Yongbai Yuan Tongxu | 2005 | Applied Mathematics Letters2005，18，： | 1 |
| 7 | Development of a photocatalytic wet scrubbing process for gaseous odor treatment 显示文摘 | L1U Tongxu LI Xiangzhong LI Fangbai | 2010 | Industrial & Engineering Chemistry Research2010，49，8： | 1 |
| 8 | New insight into iron biogeochemical cycling in soil-rice plant system using iron isotope fractionation显示文摘Iron (Fe) migration in soil-plants is a critical part of Fe biogeochemical cycling in the earth surface system. Fe isotope fractionation analysis in the soil-rice system is promising for quantitatively assessing various pathways and clarifying Fe transformation processes. However, the mechanisms of Fe isotope fractionation in the soil-rice system are not well understood. In this study, the Fe isotopic compositions (δ^(56)Fe) of rhizosphere soils, pore water, Fe plaque, and rice plant tissues at the jointing and mature stages of the plants were determined. The rice plants were slightly enriched in heavier δ^(56)Fe by 0.3‰ relative to the soil, and the stele and cortex showed similar δ^(56)Fe values, indicating that the uptake of Fe by rice plants predominantly occurred via Fe(III)-phytosiderophores (Fe(III)-PS) chelation, but not Fe(III) reduction. Additionally, at both the jointing and mature stages, the rice plant tissues showed similar δ^(56)Fe values. However, the Fe isotope fractionation between the roots and stems (Δ56Feroot−stem) was 1.39 ± 0.13‰, which is similar to the previously Ab initio-calculated values between Fe(III)-citrate and Fe(III)- 2-deoxymugineic acid (DMA), indicating that both the phloem and xylem have similar δ^(56)Fe values, and the major Fe-chelating substances in the phloem of the rice plants are Fe(III)-DMA and Fe(II)- Nicotianamine (NA). Therefore, this study demonstrates that Fe isotope fractionation can be used as a signature for interpreting the Fe uptake and translocation mechanism in the soil-rice system. | Guojun Chen Tongxu Liu Yongzhu Li Ting Gao Fang Huang Xiaomin Li Songxiong Zhong Fangbai Li | 2021 | Fundamental Research2021，1，3： | 1 |
| 9 | Development of a photocat- alytic wet scrubbing process for gaseous odor treatment 显示文摘 | Liu Tongxu Li Xiangzhong Li Fangbai | 2010 | Indus- trial & Engineering Chemistry Research2010，49，8： | 1 |
| 10 | Effects of Cd on reductive transformation of lepidocrocite by Shewanella oneidensis MR-1显示文摘We investigated the reduction of lepidocrocite(γ-FeOOH) by Shewanella oneidensis MR-1 in the presence and absence of Cd. The results showed that Cd^(2+) retarded microbial reduction of γ-Fe OOH and avoided formation of magnetite. The inhibitory effect on γ-Fe OOH transformation may not result from Cd^(2+) toxicity to the bacterium; it rather was probably due to competitive adsorption between Cd^(2+) and Fe^(2+) on γ-Fe OOH as its surface reduction catalyzed by adsorbed Fe^(2+) was eliminated by adsorption of Cd^(2+). | Chaolei Yuan Fangbai Li Rui Han Tongxu Liu Weimin Sun Weilin Huang | 2017 | Acta Geochimica2017，36，3： | 0 |
| 11 | Microaerobic iron oxidation and carbon assimilation and associated microbial community in paddy soil显示文摘Iron oxidation is a prevalent and important biogeochemical process in paddy soil,but little is known about whether and how microbially mediated iron oxidation is coupled with carbon assimilation,particularly under microaerobic conditions.Here,we investigated kinetics of CO_2 assimilation and Fe(Ⅱ)oxidation in an incubation experiment with paddy soil under suboxic conditions,and profiled the associated microbial community using DNA-stable isotope probing and 16S r RNA gene-based sequencing.The results showed that CO_2 assimilation and Fe(II)oxidation in the gradient tubes were predominantly mediated by the microbes enriched in the paddy soil,primarily Azospirillum and Magnetospirillum,as their relative abundances were higher in the^( 13)C heavy fractions compared to^( 12)C heavy fractions.This study provided direct evidence of chemoautotrophic microaerophiles linking iron oxidation and carbon assimilation at the oxic–anoxic interface in the paddy soil ecosystem. | Yating Chen Xiaomin Li Tongxu Liu Fangbai Li | 2017 | Acta Geochimica2017，36，3： | 0 |
| 12 | Chromium transformation driven by iron redox cycling in basalt-derived paddy soil with high geological background values显示文摘The flooding and drainage of paddy fields has great effects on the transformation of heavy metals, however, the transformation of Cr in basalt-derived paddy soil with high geological background values was less recognized. The typical basalt-derived paddy soil was incubated under alternating redox conditions. The Cr fractions and the dynamics of Fe/N/S/C were examined. The HCl-extractable Cr increased under anaerobic condition and then decreased during aerobic stage. The UV-vis spectra of the supernatant showed that amounts of colloids were released under anaerobic condition, and then re-aggregated during aerobic phase. The scanning transmission electron microscopy(TEM) and X-ray photoelectron spectroscopy(XPS) revealed that Fe oxides were reduced and became dispersed during anaerobic stage, whereas Fe(Ⅱ) was oxidized and recrystallized under aerobic condition. Based on these results, a kinetic model was established to further distinguish the relationship between the transformation of Cr and Fe. During anaerobic phase, the reduction of Fe(Ⅲ) oxides not only directly released the structurally bound Cr, but also enhanced the breakdown of soil aggregation and dissolution of organic matter causing indirect mobilization of Cr. During aerobic phase, the oxidation of Fe (Ⅱ) and further recrystallization of newly formed Fe(Ⅲ) oxides might induce the re-aggregation of soil colloids and further incorporation of Cr. In addition,the kinetic model of Cr and Fe transformation was further verified in the pot experiment.The model-based findings demonstrated that the Cr transformation in the basalt-derived paddy soil with high geological background values was highly driven by redox sensitive iron cycling. | Ke Zhang Yang Yang Wenting Chi Guojun Chen Yanhong Du Shiwen Hu Fangbai Li Tongxu Liu | 2023 | Journal of Environmental Sciences2023，，3： | 0 |
| 13 | The in situ spectral methods for examining redox status of c-type cytochromes in metal-reducing/oxidizing bacteria显示文摘The membrane-associated c-type cytochromes(c-Cyts) have been well known as the key enzymes mediating extracellular electron transfer to terminal electron acceptors, resulting in biogeochemical elemental transformation, contaminant degradation, and nutrient cycling. Although c-Cyts-mediated metal reduction or oxidation have been mainly investigated with the purified proteins of metal reducing/oxidizing bacteria, the in vivo behavior of c-Cyts is still unclear, given the difficulty in measuring the proteins of intact cells. Fortunately, the in situ spectroscopy would be ideal for measuring the reaction kinetics of c-Cyts in intact cells under noninvasive physiological conditions. It can also help the establishment of kinetic/thermodynamic models of extracellular electron transfer processes, which are essential to understand the electron transfer mechanisms at the molecular scale. This review briefly summarizes the current advances in spectral methods for examining the c-Cyts in intact cells of dissimilatory metal reducing bacteria and Fe(Ⅱ)-oxidizing bacteria. | Xiaobo Luo Yundang Wu Xiaomin Li Dandan Chen Ying Wang Fangbai Li Tongxu Liu | 2017 | Acta Geochimica2017，36，3： | 0 |
| 14 | Effects of zero-valent iron added in the flooding or drainage process on cadmium immobilization in an acid paddy soil显示文摘Zero-valent iron(ZVI)is a promising material for the remediation of Cd-contaminated paddy soils.However,the effects of ZVI added during flooding or drainage processes on cadmium(Cd)retention remain unclear.Herein,Cd-contaminated paddy soil was incubated for 40days of flooding and then for 15 days of drainage,and the underlying mechanisms of Cd immobilization coupled with Fe/S/N redox processes were investigated.The addition of ZVI to the flooding process was more conducive to Cd immobilization.Less potential available Cd was detected by adding ZVI before flooding,which may be due to the increase in paddy soil pH and newly formed secondary Fe minerals.Moreover,the reductive dissolution of Fe minerals promoted the release of soil colloids,thereby increasing significantly the surface sites and causing Cd immobilization.Additionally,the addition of ZVI before flooding played a vital role in Cd retention after soil drainage.In contrast,the addition of ZVI in the drainage phase was not conducive to Cd retention,which might be due to the rapid decrease in soil pH that inhibited Cd adsorption and further immobilization on soil surfaces.The findings of this study demonstrated that Cd availability in paddy soil was largely reduced by adding ZVI during the flooding period and provide a novel insight into the mechanisms of ZVI remediation in Cd-contaminated paddy soils. | Hanbing Meng Shiwen Hu Zebin Hong Wenting Chi Guojun Chen Kuan Cheng QiWang Tongxu Liu Fangbai Li Kexue Liu Yang Yang | 2024 | Journal of Environmental Sciences2024，，4： | 0 |
| 15 | Finite Element Simulation of Temperature Variations in Concrete Bridge Girders显示文摘The internal temperature of cast-in-place concrete bridges undergoes strong variations during the construction as a result of environmental factors.In order to determine precisely such variations,the present study relies on the finite element method,used to model the bridge box girder section and simulate the internal temperature distribution during construction.The numerical results display good agreement with measured temperature values.It is shown that when the external temperature is higher,and the internal and external temperature difference is relatively small,the deviation of the fitting line from existing specifications(Chinese specification,American specification,New Zealand specification)is relatively large and vice versa. | Hongzhi Liu Shasha Wu Yongjun Zhang Tongxu Hu | 2023 | Fluid Dynamics & Materials Processing2023，19，6： | 0 |
| 16 | (±)-Pyriindolin with a 2,2'-bipyridine-spiro[furan-3,3'-indoline]chimeric skeleton from the endophytic Streptomyces albolongus EA12432显示文摘(±)-Pyriindolin(1)with a rare molecular backbone formed by fusing a 2,2'-bipyridine nucleus into a spiro[furan-3,3'-indoline]skeleton,was isolated from the Streptomyces albolongus EA12432.The constitution and the relative configuration of(±)-1 were determined by extensive spectroscopic analyses,^(13)C calculation and DP4+probability analysis.The absolute configurations of optically pure(+)-1 and(-)-1 which were obtained after a chiral high performance liquid chromatography(HPLC)separation were further identified by electronic circular dichroism(ECD)calculations.(+)-and(-)-Pyriindolins displayed moderate cytotoxicity against HCT-116 cell line with the half-maximal inhibitory concentration(IC_(50))values of 2.89±0.17μmol/L and 4.47±0.26μmol/L,respectively. | Mengmeng Lan Tongxu Cui Kaichun Xia Guodong Cui Yiwen Chu Peng Fu Weiming Zhu | 2022 | Chinese Chemical Letters2022，33，1： | 0 |
| 17 | Role of cytokines in promoting immune escape of FasL-expressing human colon cancer cells显示文摘AIM: To investigate the potential role of cytokines in promoting Fas ligand (FasL)-expressing colon cancer cells.METHODS: Immunohistochemical SABC method was used to observe the expression of Fas receptor and ligand in SW620 colon cancer cell line and Jurkat T cells in order to provide the morphological evidence for the functions of Fas receptor and ligand. To examine the cytotoxicity of effector cells, CytoTox96(R) non-radioactive cytotoxicity assay was adopted to measure the lactate dehydrogenase-releasing value after SW620 cells were co-cultured with Jurkat T lymphocytes.RESULTS: The FasL of colon cancer SW620 cells was positive. The positive substances were distributed in the cell membrane and cytoplasm. The Fas receptor of colon cancer SW620 cells was negative. The Fas receptor and ligand of Jurkat T lymphocytes tumed out to be positive. The positive substances were distributed in the cell membrane.After phytohemagglutinin (PHA)-stimulated Jurkat T lymphocytes were co-cultured with phorbol 12-myristate 13-acetate (PMA)-plus-ionomycin-stimulated (for 48 h) SW620ceils or tumor necrosis factor-alpha (TNF-α)-stimulated (for 48 h) SW620 cells or unstimulated SW620 cells for 4 h,the cytotoxicity of SW620 cells to PHA-stimulated Jurkat cells at effector-to-target ratios of 10:1, 5:1, 2.5:1, and 1.25:1was 74.6%, 40.8%, 32.4%, and 10.9% (F= 8.19, P<0.05);or 54.9%, 35.3%, 22.0%, and 10.3% (F= 11.12, P<0.05);or 14.9%, 10.5%, 6.9%, and 5.8% (F= 3.45, P<0.05).After PHA-stimulated Jurkat T lymphocytes were co-cultured with unstimulated SW620 cells for 8 h, the cytotoxicity of SW620 cells to PHA-stimulated Jurkat cells at effector-totarget ratios of 5:1, 2.5:1, and 1.25:1 from the experiment was 83.9%, 74.1%, and 28.5% (F= 137.04, P<0.05)respectively. Non-radioactive cytotoxicity assay showed that the apoptotic rate of Jurkat cells remarkably increased with the increase of planting concentration of SW620 cells and co-culture time after the SW620 cells were co-cultured with the Jurkat T lymphocytes. The cytotoxicity was significantly enhancedby PMA+ionomycin or TNF-α.CONCLUSION: The FasL expressed in human colon cancer cells may be regulated by endogenous factors in the microenvironment of the host and facilitate the escape of tumor cells from the host immune system. | TongXu Bao-CunSun QiangLi Xi-ShanHao | 2005 | World Journal of Gastroenterology2005，11，25： | 0 |
| 18 | Kinetics of antimony biogeochemical processes under pre-definite anaerobic and aerobic conditions in a paddy soil显示文摘While the transformation of antimony(Sb) in paddy soil has been previously investigated, the biogeochemical processes of highly chemical active Sb in the soil remain poorly understood. In addition, there is a lack of quantitative understanding of Sb transformation in soil. Therefore, in this study, the kinetics of exogenous Sb in paddy soils were investigated under anaerobic and aerobic incubation conditions. The dissolved Sb(V) and the Sb(V) extracted by diffusive gradient technique decreased under anaerobic conditions and then increased under aerobic conditions. The redox reaction of Sb occurred, and Sb bioavailability significantly decreased after 55 days of incubation. The kinetics of Fe and the scanning transmission electron microscopy analysis revealed that the Fe oxides were reduced and became dispersed under anaerobic conditions, whereas they were oxidized and re-aggregated during the aerobic stage. In addition, the redox processes of sulfur and nitrogen were detected under both anaerobic and aerobic conditions. Based on these observations, a simplified kinetic model was established to distinguish the relative contributions of the transformation processes. The bioavailability of Sb was controlled by immobilization as a result of S reduction and by mobilization as a result of Fe reductive dissolution and S oxidation, rather than the p H. These processes coupled with the redox reaction of Sb jointly resulted in the complex behavior of Sb transformation under anaerobic and aerobic conditions. The model-based method and findings of this study provide a comprehensive understanding of the Sb transformation in a complex soil biogeochemical system under changing redox conditions. | Bingqing Xia Yang Yang Fangbai Li Tongxu Liu | 2022 | Journal of Environmental Sciences2022，34，3： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员