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南极无冰区生态与环境变化在粪土层中的记录

气候变化研究进展 2007年第Z1期3卷 35-40页

作者：孙立广刘晓东 institute of polar environment University of Science and Technology of China Hefei 230026 China

The accumulative profiles of seabird and sea animal excrement together with the depositional sequences influenced by the excrement have been utilized to reconstruct the historical populations of Antarctic penguins and seals, also to study the eco-geology in the ice-free areas of Antarctica and Arctic. The historical populations of Antarctic penguins show dramatic fluctuations, the period of sharp decrease coincides well with Neoglaciation, and extremely cold or warm climate conditions are unfavorable for the survival of Antarctic penguin. The historical change of seal population seems to be related to climatic variations, sea-ice coverage and its forage behavior. The fluctuations of Hg (mercury) in the seal hairs and the sediments influenced by seal excrement were found to be closely associated with ancient gold and silver mining activities and the ancient civilization over the past several thousand years.

关键词： Antarctica sediments influenced by animal excrements penguin seal eco-environmental variation human civilization

Phylogenetic diversity of planktonic bacteria in the Chukchi Borderland region in summer

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Acta Oceanologica Sinica 2013年第6期32卷 66-74页

作者： ZENG Yinxin YU Yong LI Huirong HE Jianfeng LEE Sang H sun Kun Key Laboratory for polar science of State Oceanic Administration Polar Research Institute of China College of Biological Engineering Jimei University Department of Oceanography Pusan National University

Planktonic bacteria are abundant in the Chukchi Borderland region. However, little is known about their di- versity and the roles of various bacteria in the ocean. Seawater samples were collected from two stations K2S and K4S where sea ice was melting obviously. The analysis of water samples with fluorescence in situ hybridization （FISH） showed that DMSP-degrading bacteria accounted for 13% of the total bacteria at the station K2S. No aerobic anoxygenic phototrophic （AAP） bacteria were detected in both samples. The bacterial communities were characterized by two 16S rRNA gene clone libraries. Sequences fell into four major lineages of the domain Bacteria, including Proteobacteria （Alpha, Beta and Gamma subclasses）, Bac- teroidetes, Actinobacteria and Firmicutes. No significant difference was found between the two clone li- braries. SAR11 and Rhodobacteraceae clades of Alphaproteobacteria and Pseudoalteromonas of Gammapro- teobacteria constituted three dominant fractions in the clone libraries. A total of 191 heterotrophic bacterial strains were isolated and 76% showed extracellular proteolytic activity. Phylogenetic analysis reveals that the isolates fell into Gammaproteobacteria, Bacteroidetes, Actinobacteria and Firmicutes. The most common genus in both the bacterial isolates and protease-producing bacteria was Pseudoalteromonas. UniFrac data showed suggestive differences in bacterial communities between the Chukchi Borderland and the northern Bering Sea.

关键词： diversity planktonic bacteria 16S rRNA gene clone library Chukchi Borderland

Benzenesulfonic acid-grafted UIO-66 with improved hydrophobicity as a stable Brønsted acid catalyst

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Frontiers of Chemical science and Engineering 2023年第10期17卷 1389-1398页

作者： Zongliang Kou Guanlun sun Qiuyan Ding Hong Li Xin Gao Xiaolei Fan Xiaoxia Ou Qinhe Pan School of Chemical Engineering and technology National Engineering Research Center of Distillation TechnologyCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Department of Chemical Engineering School of EngineeringThe University of ManchesterManchester M139PLUK Nottingham Ningbo china Beacons of Excellence Research and Innovation institute University of Nottingham Ningbo ChinaNingbo 315100China Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources School of Chemical Engineering and TechnologyHainan UniversityHaikou 570228China

Hydrothermal and catalytic stability of UIO-66 MOFs with defective structures are critical aspects to be considered in their catalytic applications,especially under the conditions involving water,moisture and/or ***,we report a facile strategy to introduce the macromolecular acid group to UIO-66 to improve the stability of the resulting UIO-66−PhSO3H MOF in aqueous phase *** detail,UIO-66−PhSO3H was obtained by grafting benzenesulfonic acid on the surface of the pristine UIO-66 to introduce the hydrophobicity,as well as the Brønsted acidity,then assessed using catalytic hydrolysis of cyclohexyl acetate(to cyclohexanol)in *** introduction of hydrophobic molecules to UIO-66 could prevent the material from being attacked by hydroxyl polar molecules effectively,explaining its good structural stability during ***-66−PhSO3H promoted the conversion of cyclohexyl acetate at ca.87%,and its activity and textural properties were basically intact after the cyclic stability *** facile modification strategy can improve the hydrothermal stability of UIO-66 significantly,which can expand its catalytic applications in aqueous systems.

关键词： metal−organic frameworks(MOFs) UIO-66 hydrolysis of cyclohexyl acetate hydrophobicity Brønsted acidity

Mercury and lead in a single strand of pinnule of snow petrel (Pagodroma Nivea) in the Antarctic

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Chinese Journal Of Geochemistry 2006年第B8期25卷 196-196页

作者： Zhouqing XIE Siqi XU liguang sun Yuying HUANG Wei HE institute of polar environment School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China

燃煤电厂石灰石-石膏湿法脱硫系统中痕量元素的迁移分布规律

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环境科学研究 2023年第6期36卷 1115-1124页

作者：水玉蝶王润芳金琳琳马大卫陈剑朱仁斌杨娴中国科学技术大学极地环境与全球变化安徽省重点实验室安徽合肥230026 安徽新力电业科技咨询有限责任公司安徽合肥230601 国网安徽省电力有限公司电力科学研究院安徽合肥230601

燃煤电厂是煤炭消耗的主力军,煤炭在燃烧过程中,大量痕量元素随烟气排出.随着我国环保要求的不断提高,燃煤电厂的痕量元素排放受到广泛关注.石灰石-石膏湿法烟气脱硫(WFGD)系统不仅能高效吸收烟气中的SO_(2),同时影响痕量元素的迁移分布... 详细信息

燃煤电厂是煤炭消耗的主力军,煤炭在燃烧过程中,大量痕量元素随烟气排出.随着我国环保要求的不断提高,燃煤电厂的痕量元素排放受到广泛关注.石灰石-石膏湿法烟气脱硫(WFGD)系统不仅能高效吸收烟气中的SO_(2),同时影响痕量元素的迁移分布.本研究对安徽省3个超低排放燃煤电厂的WFGD系统中进/出口烟尘、石灰石、工业水、污泥、石膏和脱硫废水等环境样品进行了采集,研究了Cr、As、Cd、Pb和Hg等痕量元素的迁移分布特征.结果表明:①WFGD系统对烟尘中痕量元素的去除率在95%以上,脱硫污泥中Cr、As和Hg浓度分别为29.9~52.2、12.5~36.7和2.2~6.5 mg/kg,约为石膏中Cr、As和Hg浓度的7~9倍.②元素质量平衡分析表明,痕量元素主要来源于烟气和石灰石,主要输出为污泥和石膏,废水中仅富集少量Cd.研究显示,脱硫石膏和污泥的处置及再利用过程中需着重关注痕量元素的环境影响.

关键词：燃煤电厂超低排放痕量元素湿法脱硫烟气脱硫石膏

Composition and structure of coatings on Ti-6Al-4V alloy by micro-plasma oxidation in NaAlO2 solution

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 162-165页

作者： YAO Zhong-ping JIANG Zhao-hua sun Xue-tong WU Zheng-dong ZHANG Xue-lin Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China

Compound ceramic coatings on Ti-6Al-4V alloy were prepared for different time by pulsed bi-polar micro-plasma oxidation (MPO) in NaAlO2 solution. The phase composition was studied by XRD. And the electrochemical impedance spectra (EIS) of the coatings were measured to study the structure of the coatings, combined with the surface morphology. Using the proper EIS interpreting software, the "equivalent circuit" of the coatings was established, and meanwhile fitting values of equivalent element were obtained. The results show that the coating is composed of Al2 TiO5, α-Al2O3 and rutile TiO2, of which Al2 TiO5 is the main crystalline. Increasing the MPO time, the contents of Al2TiO5, rutile TiO2 and α-Al2O3 in the surface of the coating increase. And the EIS analysis and the surface morphology of the coatings illustrates the double-layer structure of the coatings, and the outer layer is loosen and the inner layer is compact. With the increase of the oxidizing time, the surface coarse degree of the coatings and the porosity of the outer layer of the coating are increased while the compactness of the inner layer of the coating is improved.

关键词： micro-plasma oxidation ceramic coatings electrochemical impedance spectra Ti-6Al-4V alloy

DNA Topoisomerase 1 Prevents R-loop Accumulation to Modulate Auxin-Regulated Root Development in Rice

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Molecular Plant 2017年第6期10卷 821-833页

作者： Sarfraz Shafiq Chunli Chen Jing Yang Lingling Cheng Fei Ma Emilie Widemann Qianwen sun Center for Plant Biology and Tsinghua-Peking Joint Center for Life sciences School of Life Sciences Tsinghua University Beijing 100084 China College of Life science and technology Huazhong Agricultural University Wuhan 430070 China Permanent affiliation: Department of environmental sciences COMSATS Institute of Information Technology Abbottabad 22060 Pakistan

R-loop structures （RNA：DNA hybrids） have important functions in many biological processes, including transcriptional regulation and genome instability among diverse organisms. DNA topoisomerase 1 （TOP1）, an essential manipulator of DNA topology during RNA transcription and DNA replication processes, can prevent R-loop accumulation by removing the positive and negative DNA supercoiling that is made by RNA polymerases during transcription. TOP1 is required for plant development, but little is known about its function in preventing co-transcriptional R-loop accumulation in various biological processes in plants. Here we show that knockdown of OsTOP1 strongly affects rice development, causing defects in root archi- tecture and gravitropism, which are the consequences of misregulation of auxin signaling and transporter genes. We found that R-loops are naturally formed at rice auxin-related gene loci, and overaccumulate when OsTOP1 is knocked down or OsTOP1 protein activity is inhibited. OsTOP1 therefore sets the accurate expression levels of auxin-related genes by preventing the overaccumulation of inherent R-loops. Our data reveal R-loops as important factors in polar auxin transport and plant root development, and highlight that OsTOP1 functions as a key to link transcriptional R-loops with plant hormone signaling, provide new in- sights into transcriptional regulation of hormone signaling in plants.

关键词： R-loops DNA TOP1 auxin signaling root development

智绘地质——新一代智能化地质编图模式及应用

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地质通报 2020年第6期39卷 861-870页

作者：李仰春王永志陈圆圆孟祥卉孙仁斌蒋作瑞林燕中国地质调查局发展研究中心北京100037 吉林大学综合信息矿产预测研究所吉林长春130061 吉林大学地球探测科学与技术学院吉林长春130061 河北省区域地质调查院河北廊坊065000 北京创时空科技发展有限公司北京100083 中国煤炭地质总局勘查研究总院北京100039

为了弥补传统数字地质编图工作量大、重复操作多、周期长、质量难保证等不足,从地质图件快速编制的业务需求出发,提出了多学科交叉的智能地质综合编图理念,构建了以"地质数据+专家知识+人工智能"为核心的智能化地质编图技术体系,研制了... 详细信息

为了弥补传统数字地质编图工作量大、重复操作多、周期长、质量难保证等不足,从地质图件快速编制的业务需求出发,提出了多学科交叉的智能地质综合编图理念,构建了以"地质数据+专家知识+人工智能"为核心的智能化地质编图技术体系,研制了具有需求驱动、数据驱动、模型驱动、知识驱动等特点的地质调查综合智能编图系统--智绘地质。智绘地质以地质专家知识为全流程控制主线,有机融合地图综合、地理信息系统、数据库、可视化、人工智能、制图标准、质量控制等关键技术和方法,依托地质演化关系、各种规则库、智能算法等,模拟编图专家自动或半自动地完成大量地质要素的综合处理,打通了大中比例尺到小比例尺图件的快速缩编、基础图件编制、跨行政边界的协作编图、定制化图件开发等技术流程。智绘地质已在中国1∶150万和1∶250万地质图修编、区域地质图件编制、沿海城市建设影响因素图件开发等生产工作中试用,实践证明该软件至少能节省65%~75%的编图时间,减轻编图人员压力,有效提高成果数据质量。开发的两套智绘地质软件已初步投入使用,有利于开启新一代交互式智能化编图的工作模式,可为地质调查、矿产资源、生态保护、国际编图等更多领域提供技术支撑,促进编图工作的标准化、规范化。

关键词：地图综合地质编图智绘地质人工智能地理信息系统地质专家知识

Feeding strategies of Euphausia superba in the eastern South Shetland Islands in austral summer

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Acta Oceanologica Sinica 2019年第10期38卷 75-83页

作者： Mengtan Liu Zhencheng Tao Ye Zhang Guang Yang Song sun Chaolun Li Fengfeng Le Jiaozhou Bay National Marine Ecosystem Research Station Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and environmental science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Center for Ocean Mega-science Chinese Academy of SciencesQingdao 266071China Key Laboratory of Marine Ecology and environmental sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China East Sea Marine environmental Investigating and Surveying Center Ministry of Natural ResourcesShanghai 200137China Laboratory of Marine Ecosystem and Biogeochemistry Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China

Euphausia superba is a key species in the Southern Ocean that serves as a link between primary production and higher trophic *** investigate the feeding strategies of *** from the eastern South Shetland Islands,fatty acid biomarkers,stable isotope signatures,and an incubation experiment were *** results of the incubation experiment proved that adult *** mainly fed on 2–20μm particles,demonstrating the importance of nanoplankton in their ***,significant positive relationships betweenδ15N and body size demonstrated that size-related dietary shifts were present in *** from principal component analysis and the C16:1ω7/C18:4ω3 ratio showed that juveniles preferentially fed on dinoflagellates and adults were more likely to feed on *** acid profiles in adult *** roughly mirrored the different trophic conditions and feeding strategies between *** *** at Stas D2-07,D5-07,DA-01 and DA-02 exhibited elevated levels of C16:1ω7,C18:4ω3,C18:1ω9 and C18:1ω9/C18:1ω7,indicating higher levels of feeding on both phytoplankton and higher trophic *** contrast,adult *** at Stas D1-03 and D1-04 were characterized by high levels of polyunsaturated fatty acids/saturated fatty acids ratios and low levels of C16:1ω7,C18:1ω7,C18:4ω3,C18:1ω9 and total fatty *** inferred that adult krill at Stas D1-03 and D1-04 still suffered from difficult dietary conditions after *** different dietary conditions between stations suggest a highly plastic feeding strategy of *** in the eastern South Shetland Islands.

关键词： Euphausia superba South Shetland Islands fatty acids stable isotopes