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Distribution of functional microorganisms and its significance for iron, sulphur, and nitrogen cycles in reservoir sediments

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Acta Geochimica 2021年第6期40卷 961-972页

作者： Shuang Bai Meilin Yang zheng chen Ming Yang Jing Ma Xue-Ping chen Fushun Wang School of Environmental and Chemical Engineering Shanghai University99 Shangda RoadBaoShan DistrictShanghai 200444China Department of Health and Environmental Sciences Xi’an Jiaotong-Liverpool UniversitySuzhou 215123JiangsuChina

The biogeochemical cycles of sulphur(S),iron(Fe)and nitrogen(N)elements play a key role in the reservoir ***,the spatial positioning and interrelationship of S,Fe and N cycles in the reservoir sediment profile have not been explored to a greater ***,we measure the gradients of Fe^(2+),SO_(4)^(2-),NO_(3)^(-),NH_(4)^(+),DOC,TC and TN in the pore water of the sediment,and combining the vertical distribution of the functional microorganisms involved in S,Fe and N cyclings in the sediments to determine the redox stratification in the *** is found that the geochemical gradient of S,Fe and N of the reservoir sedimentary column is mainly defined by the redox process involved in the related functional *** to the type of electron acceptor,the sediment profile is divided into 3 redox intervals,namely aerobic respiration(0–10 cm),denitrification/iron reduction(10–28 cm)and sulfate reduction(28–32 cm).In the aerobic respiration zone,NH_(4)^(+)is oxidized by aerobic AOB to NO_(3)^(-)(0–5 cm),and Fe^(2+)is oxidized by microaerobic FeRB to Fe^(3+)(3–10 cm).In the denitrification/iron reduction zone,Acinetobacter and Pseudomonas,as the dominant NRB genera,may use nitrate as an electron acceptor to oxidize Fe^(2+)(11–16 cm).The dominant genera in SOB,such as Sulfururvum,Thiobacillus and Thioalkalispira,may use nitrate as an electron acceptor to oxidize sulfide,leading to SO_(4)^(2-)accumulation(14–24 cm).In the sulfate reduction zone,SO_(4)^(2-)is reduced by *** study found that functional microorganisms forming comprehensive local ecological structures to adapt to changing geochemical conditions,and which would be potentially important for the degradation and preservation of C and the fate of many nutrients and contaminants in reservoirs.

关键词： Reservoir sediment Geochemical cycle Microbial community Redox Denitrification

Real time path planning via alternating minimisation through image information

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IET Cyber-Systems and Robotics 2021年第3期3卷 245-255页

作者： zheng chen Minjie Zhang Jiang Zhu Shiqiang Zhu Hainan Institute of Zhejiang University SanyaChina Ocean College Zhejiang UniversityZhoushanChina

Real time path planning from image information is of vital importance in the fields of robots as it has various applications in real time navigation,autonomous driving,robot arm manipulation and human robot cooperation and so *** achieve this task,a two stage approach is *** the first stage,a novel change point detection approach is proposed to process the image to extract the shape of the *** the second stage,several novel approximations are adopted to make the path planning problem ***,the irregular shapes of the obstacles in the environment are approximated as lines and circles,which simplify the distance constraint ***,the non-convex path planning problem is iteratively decomposed as a sequence of subproblems and alternating minimisation method is proposed to efficiently solve the *** improve the quality of the solution,good initial points obtained by A*algorithm is *** numerical experiments and real experiments are conducted to demonstrate the effectiveness of the proposed algorithm.

关键词： PATH PLANNING ROBOT MANIPULATOR

Inhibition of cell proliferation,migration and apoptosis in blue-light illuminated human retinal pigment epithelium cells by down-regulation of HtrA1

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International Journal of Ophthalmology(English edition) 2017年第4期10卷 524-529页

作者： Tian Yu Chang-zheng chen Yi-Qiao Xing Eye Center Renmin Hospital of Wuhan University

AIM：To investigate the effect of Htr A1 on the proliferation,migration and apoptosis of human retinal pigment epithelium（RPE） cells in the light injured model,as well as the expression of the apoptosis related ***：The human RPE cell line ARPE-19 was exposed to blue light to establish the light injured *** cells were transfected with Htr A1 si RNA to knockdown Htr A1 *** expression of Htr A1 was determined by real-time polymerase chain reaction（RTPCR） and Western blot,*** in cell proliferation,migration and apoptosis were assessed by cell counting kit-8（CCK-8）,Transwell assay and flow cytometry respectively,as well as changes in the m RNA and protein levels of Bax,Caspase-3 and Bcl-2 ***：Htr A1 was highly expressed in ARPE-19 cells after blue light *** of Htr A1 expression inhibited the proliferation,migration and apoptosis of the blue-light-irradiated ARPE-19 cells（P〈0.05）.Bax and Caspase-3 expression were significantly reduced both at m RNA and protein levels（P〈0.05） after si RNA ***-2 expression significantly increased in blue-lightirradiated ARPE-19 cells after si RNA interference（P〈0.05）.CONCLUSION：Silence of Htr A1 may inhibit the proliferation,migration and apoptosis of ARPE-19 cells in light injured ***,Htr A1 suppression in blue-lightirradiated ARPE-19 cells may ameliorate cell apoptosis through down-regulation of Bax and Caspase-3,and upregulation of Bcl-2 expression.

关键词： HtrA1 retinal pigment epithelium small interfering RNA

50 ppm of Pd dispersed on Ni（OH）2 nanosheets catalyzing semi-hydrogenation of acetylene with high activity and selectivity

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Nano Research 2018年第2期11卷 905-912页

作者： Hu, Mingzhen Zhang, Jian Zhu, Wei chen, zheng Gao, Xin Du, Xianjun Wan, Jiawei Zhou, Kebin chen, chen Li, Yadong School of Chemistry and Chemical Engineering University of Chinese Academy of Sciences Beijing China Department of Chemistry Tsinghua University Beijing China

We report a highly efficient Pd/Ni（OH）2 catalyst loaded with ultra-low levels of palladium （50 ppm Pd by mass） for the selective hydrogenation of acetylene to ethylene. The turnover frequency for acetylene conversion over the 0.005% Pd/Ni（OH）2 catalyst is twice that of the equivalent 0.8% Pd/Ni（OH）2 catalyst. Notabl an acetylene-to-ethylene selectivity of 80% was achieved over a wide range of temperatures. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy was used to reveal the atomically dispersed nature of palladium in the 0.005% Pd/Ni（OH）2 catalyst. The excellent selectivity of this catalyst is attributed to its atomically dispersed Pd sites, while the abundant hydroxyl groups of the support significantly enhance the acetylene conversion activity. This work opens up innovative opportunities for new types of highly efficient catalysts with trace noble-metal loadings for a wide variety of reactions.

关键词： catalyst trace-loading palladium hydrogenation

Formation Mechanism of the High-quality Upper Paleozoic Natural Gas Reservoirs in the Ordos Basin

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Acta Geologica Sinica(English Edition) 2005年第6期79卷 843-855页

作者： ZHAO Wenzhi WANG Zecheng chen Menjin zheng Hongju Research Institute of Petroleum Exploration and Development Petrochina Beijing 100083

The upper Paleozoic natural gas reservoirs in the Ordos basin are generally characterized by a large gas-bearing area and low reserve abundance. On such a geological background, there still exist gas-enriched zones, with relatively high outputs, high reserve abundance and stably distributed gas layers. The gas-enriched layers with relatively high permeability （the lower limit permeability is 0.5×10^-3μm^2） are key factors for the enrichment and high output of natural gas. Based on core observation, analytic results of inclusions, and a great deal of drilling data, we proposed the following four mechanisms for the formation of high-quality reservoirs：（1） in the source area the parent rocks are mainly metamorphic rocks and granites, which are favorable to keeping primary porosity; （2） under the condition of low A/S （accommodation/sediment supply） ratios, sandstone complex formed due to multistage fluvial stacking and filling are coarse in grain size with a high degree of sorting, low content of mud and good physical properties; （3） early-stage recharge of hydrocarbons restricted compaction and cementation, and thus are favorable to preservation of primary pores; （4） microfractures caused by the activity of basement faults during the Yanshan Movement stage can not only improve the permeability of tight sandstones, but also afford vertical pathways for hydrocarbon gas migration.

关键词： lithology of parent rock A/S ratio recharge of hydrocarbons microfractures multistage fluvial complex upper Paleozoic Ordos Basin

Microscopic phase-field study for oriented diffusion channel effect of nickel-based alloy and phases' effect mechanism

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Science China(Technological Sciences) 2011年第4期54卷 835-840页

作者： YANG Kun chen zheng DONG WeiPing WANG YongXin ZHANG MingYi State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China

In this paper,a microscopic phase-field model was used to investigate the effect of the oriented diffusion channel and the phases' effect mechanism for the Ni75Al6.0V19.0 alloy during a phase transformation process.A diffusion channel of V was formed in the [100] *** oriented growth of DO22 in this direction,when an elastic misfit stress field existed,forced Al to form a diffusion channel next to DO22,resulting in L12-oriented *** an increase in stress,the oriented growth increased initially and then *** a higher stress,the average values of the occupation probability for V atoms became constant later while Al atoms earlier.

关键词： diffusion channel effect stresses-induced diffusion diffusion-induced stresses microscopic phase-field

Effect of NHE1 antisense gene transfection on the biological behavior of SGC-7901 human gastric carcinoma cells

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World Journal of Gastroenterology 2008年第14期14卷 2162-2167页

作者： Hai-Feng Liu Xiao-Chun Teng Jing-chen zheng Gang chen Xing-Wei Wang Department of Gastroenterology General Hospital of Chinese People's Armed Police Forces Beijing 100039 China Department of Gastroenterology Southwest Hospital Third Military Medical University Chongqing 400038 China

AIM: To study the effect of type 1 Na+/H+ exchanger (NHE1 ) antisense human gene transfection on the biological behavior of gastric carcinoma cell line SGC-7901. METHODS: Antisense NHE1 eukaryotic expression on vector pcDNA3.1 was constructed by recombinant DNA technique and transfected into gastric carcinoma cell line SGC-7901 with DOTAP liposome transfection method. Morphological changes of cells were observed with optic and electron microscopes. Changes in cell proliferative capacity, apoptosis, intracellular pH (pHi), cell cycle, clone formation in two-layer soft agar, and tumorigenicity in nude mice were examined. RESULTS: Antisense eukaryotic expressing vectors were successfully constructed and transfected into SGC-7901. The transfectant obtained named 7901 -antisense (7901-AS) stablely produced antisense NHE1. There was a significant difference between the pHi of 7901-AS cells (6.77 ± 0.05) and that of 7901-zeo cells and SGC-7901 cells (7.24 ± 0.03 and 7.26 ± 0.03, P < 0.01). Compared with SGC-7901 and 7901-zeo cells, 7901-AS cells mostly showed cell proliferation inhibition, G1/G0 phase arrest, increased cell apoptotic rate, recovery of contact inhibition, and density contact. The tumorigenicity in nude mice and cloning efficiency in the two-layer soft agar were clearly inhibited. CONCLUSION: NHE1 antisense gene significantly restrains the malignant behavior of human gastric carcinoma cells, suppresses cell growth and induces cell apoptosis, and partially reverses the malignant phenotypes of SGC-7901 . These results suggest a potential role for human tumor gene therapy.

关键词： NHE1 gene Eukaryotic expression vector Antisense gene therapy Gastric cancer

One-pot Syntheses of Spinel AB2O4 （A=Ni or Co, B=Mn or Fe） Microspheres with Different Hollow Interiors for Supercapacitors Application

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Chinese Journal of Chemistry 2017年第1期35卷 67-72页

作者： Ge Liu Jie Shao Youjun Gao zheng chen Qunting Qu Department of Chemistry Chifeng University Chifeng Inner Mongolia 024000 China College of Physics Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow University Suzhou Jiangsu 215006 China College of Chemical and Biological Engineering Hezhou University Hezhou Guangxi 542899 China

Spinel NiMn2O4, CoMn2O4, NiFe2O4 and CoFe2O4 hollow microspheres are prepared through an easy and general approach. The preparation procedures include the one-pot hydrothermal treatment of mixed metal salts and glucose, and subsequent calcination. The different penetration ability of Mn2＋ and Fe3＋ precursor ions into the interior of glucose-derived carbon microspheres results in single-shelled manganites and triple-shelled ferrites, respectively. Investigations on the electrochemical behaviors of the as-prepared four bimetal oxides show that they possess good supercapacitive properties in aqueous electrolytes.

关键词： hollow microspheres ferrites manganites spinel supercapacitors

Cobalt-manganese bimetallic organic frameworks catalyzed solvent-free oxidation of benzyl C-H bonds with O_(2) as sole oxidant

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Nano Research 2024年第11期17卷 9532-9539页

作者： Ke Cao Yan Zhou Shanshan Lv Mengmeng Feng Changjin Qian zheng chen Key Laboratory of Functional Molecular Solids Ministry of Education College of Chemistry and Materials Science Anhui Normal University Wuhu 241002 China State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210023 China

The selective oxidation of hydrocarbons can be used to produce oxygen-containing functional compounds such as alcohols, aldehydes or ketones and its efficient and green conversion lies in the development of efficient catalysts that activate C-H bonds and O_(2) simultaneously. In this work, the bimetallic organic framework (CoMnBDC) material with morphology of stacked nanosheets was synthesized using terephthalic acid as ligands to coordinate with Co^(2+) and Mn^(2+) cations under solvothermal conditions. As revealed by spectroscopic characterizations, the electron transfer from Mn to Co in the CoMnBDC resulted in the reduction of the Co average oxidation state and increase of the Mn average oxidation state. The CoMnBDC nanosheets were used as catalyst in catalytic oxidation of ethylbenzene, in which the redox effect promotes the effective electron transfer, the activation of O_(2) and benzyl C-H bond. The 96.2% conversion of ethylbenzene and 98.0% selectivity towards acetophenone could be obtained with oxygen as sole oxidant and solvent-free condition. The excellent catalytic performance is related to the structure of CoMnBDC and is also the best when compared with reported results. Various types of aromatic hydrocarbons containing benzyl C-H bonds can be effectively oxidized by CoMnBDC to produce corresponding ketone products. The density functional theory (DFT) calculation revealed that the redox effect leads to the relative enrichment of electrons on Co in CoMnBDC, which is conducive to the activation of O_(2);Mn with higher oxidation state is beneficial for the adsorption of ethylbenzene and activation of C-H bonds. The CoMnBDC has a lower energy barrier for transition state, making it easier for the ethylbenzene oxidation to produce acetophenone.

关键词： metallic organic framework transition metal nanocatalysis oxidation ketone