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Complexation of DNA with cationic surfactants as studied by small-angle X-ray scattering

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Science China Chemistry 2014年第12期57卷 1738-1745页

作者： NIU Lin YAN JingJing YANG XuYan BURGER Christian RONG LiXia HSIAO Benjamin LIANG dehai Beijing National Laboratory for Molecular Sciences the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education Department of Polymer Science and Engineering College of Chemistry and Molecular Engineering Peking University Department of Chemistry State University of New York at Stony Brook

The phase behaviors of the complex formed by didodecyldimethylammonium bromide（DDAB）and cetyltrimethylammonium bromide（CTAB）interacting with three different types of DNAs,salmon testes DNA（~2000 bp）,21-bp double-stranded oligonucleotides（oligo-ds DNA）,and 21-nt single-stranded oligonucleotides（oligo-ss DNA）were studied by synchrotron small-angle X-ray *** was found that the DNA length and flexibility,together with the positive/negative charge ratio,determined the final *** higher charge ratios,the DNA length exhibited negligible *** oligo-ds DNA and salmon DNA formed inverted hexagonal packing of cylinders with CTAB,as well as bilayered lamella with ***,at lower charge ratios,oligo-ds DNA formed a distorted hexagonal phase with CTAB and a new structure with DDAB,which was different from the behaviors of salmon *** flexible oligo-ss DNA formed rich structures that were subject to environmental *** study also indicated that the structures of the complex formed by oligo-ss DNA took much longer to mature than the structures formed by oligo-ds *** attributed this result to the conformational adjustment of oligo-ss DNA in the complex.

关键词： phase behavior DNA surfactant synchrotron small-angle X-ray scattering kinetics

Immunosuppressant mycophenolic acid biosynthesis employs a new globin-like enzyme for prenyl side chain cleavage

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Acta Pharmaceutica Sinica B 2019年第6期9卷 1253-1258页

作者： Xiwei Chen Lu Wang Jinmei Zhang Tao Jiang Changhua Hu dehai Li Yi Zou College of Pharmaceutical Sciences Southwest UniversityChongqing 400715China Key Laboratory of Marine Drugs Chinese Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Biological Science Research Center Southwest UniversityChongqing 400715China

Mycophenolic acid(MPA,1)and its derivatives are first-line immunosuppressants used in organ transplantation and for treating autoimmune *** chemical synthetic achievements,the biosynthetic formation of a seven-carbon carboxylic acid pharmacophore side chain of 1,especially the processes involving the cleavage of the prenyl side chain between DHMP(4)and DMMPA(5),remains *** this work,we identified a membrane-bound prenyltransferase,PgMpaA,that transfers FPP to 4 to yield FDHMP(6).Compound 6 undergoes the first cleavage step via a new globin-like enzyme PgMpaB to form a cryptic intermediate *** expression of PgMpa genes in Aspergillus nidulans demonstrates that the second cleavage step(from 12 to 5)of 1 is a PgMpa clusterindependent process in *** results,especially the discovery of the broad tolerance of substrates recognized by PgMpaB,set up a strategy for the formation of"pseudo-isopentenyl"natural products using fungal globin-like enzymes.

关键词： Biosynthesis Mycophenolic acid Prenylation C-C bond cleavage Globin enzyme

Liquid metal hydraulics paradigm:Transmission medium and actuation of bimodal signals

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Science China(Technological Sciences) 2022年第1期65卷 77-86页

作者： FU JunHeng GAO JianYe QN Peng LI DongDong YU dehai SUN Peng HE ZhiZhu DENG ZhongShan LIU Jing Beijing Key Laboratory of Cryo-Biomedical Engineering and Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China School of Future Technology University of Chinese Academy of SciencesBeijing 100049China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China Department of Biomedical Engineering School of MedicineTsinghua UniversityBeijing 100084China Department of Vehicle Engineering College of EngineeringChina Agricultural UniversityBeijing 100083China

In this article,room temperature gallium-based fluids(RTGFs)with unique thermal and conductive properties are proposed as a transmission fluid for the force carrying medium of hydraulics,which rectify the lack of the multi-functional hydraulic roles of liquid metal(LM).The typical physical properties of RTGFs and comparative conventional hydraulic fluids(commercial hydraulic oil and deionized water),such as thermal stability and rheological characteristics,are *** and numerical methods,then,were adopted to clarify the force transmission performance of RTGFs and commercial hydraulic oils,as well as the influence of temperature fields on the viscosity of *** results disclosed that the advantages of inherent flame resistance,wide liquid temperature range,and the viscosity changing slightly with temperature made RTGFs potential in finding efficient application in the hydraulics as new working ***,for illustration,the rigid and flexible actuators driven by RTGFs were designed as hydraulic fluid and demonstrated their capabilities in grasping objects with various shapes and weights,*** the tunable stiffness of such a flexible actuator was enabled via the solid-liquid phase change of ***,a frequency-adjustable antenna was manufactured and showcased owing to the introduced transformable electromagnetic behaviors of ***,the gallium-based LM fluids with thermoelectrical and mechanical multimodal signal medium would serve as a potential candidate for future complex multifunctional signal transmission systems.

关键词： hydraulic system LM force transmission phase change controllable antenna

Numerical Study on Seasonal Transportation of the Suspended Sediments in the Modern Yellow River Mouth Effected by the Artificial Water and Sediment Regulation

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Journal of Ocean University of China 2019年第1期18卷 20-30页

作者： WANG Nan QIAO Lulu LI Guangxue ZHONG Yi SONG dehai DING Dong GAO Fei JI Fengying College of Oceanic and Atmospheric Ocean University of China College of Marine Geosciences Ocean University of China Key Laboratory of Submarine Sciences & Prospecting Techniques MOE Ocean University of China Key Laboratory of Physical Oceanography MOE Ocean University of China Key Laboratory of Marine Hydrocarbon Resources and Environmental Geology Ministry of Land and Resources Qingdao Institute of Marine Geology National Marine Data and Information Service

Since 2002, an artificial water and sediment regulation(AWSR) has been carried out, which largely reduced water and sediment discharged from the Yellow River into the Bohai Sea. Although the sediment transport in the Yellow River Mouth(YRM) has been observed and modeled intensively since AWSR, but preferentially for the non-storm conditions. In this study, a three-dimensional current-wave-sediment coupled model, DHI-MIKE numerical model, was used to examine the seasonal suspended-sediment transport in the YRM after the AWSR. Results show that the seasonal distribution of suspended-sediments in the YRM is dominated by wind and wave rather than river input. The major transport pathway of suspended-sediments is from the western Laizhou Bay to the Bohai Strait during the winter monsoon, especially in storm events. In addition, about 66% of the river sediments deposit within 30 km of the YRM, which is smaller than previous estimations. It suggests that the YRM has been eroded in recent decades.

关键词： Yellow River Mouth artificial water and sediment regulation MIKE suspended-sediment transport seasonal variation

经济新常态、污染防治与政府规制:环境突发事件演化博弈模型

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系统工程理论与实践 2021年第6期41卷 1454-1464页

作者：宋民雪刘德海尹伟巍东北财经大学管理科学与工程学院大连116025 辽宁警察学院治安系大连116036

推进污染防治取得更大成效是我国全面建成小康社会三大攻坚战之一,经济新常态下地方政府面临着环境保护与稳增长保就业的权衡.考虑周边群众抗议环境污染事件的社会稳定压力,供给侧改革下传统重化工企业环保和转型发展压力,构建了周边群... 详细信息

推进污染防治取得更大成效是我国全面建成小康社会三大攻坚战之一,经济新常态下地方政府面临着环境保护与稳增长保就业的权衡.考虑周边群众抗议环境污染事件的社会稳定压力,供给侧改革下传统重化工企业环保和转型发展压力,构建了周边群众与企业的自发演化博弈模型,然后讨论政府规制下周边群众与企业的受控演化博弈过程.通过演化均衡分析和案例研究,解释了企业排污和周边群众抗议行为的周期性波动;为了达到{接受,承担社会责任}的演化均衡,政府需要执行适宜的环境规制强度区间;企业生产营业额越大,政府执行环境规制政策的可操作空间越大.本文研究为政府实现高质量发展与保就业双赢提供有益参考借鉴.

关键词：政府规制群体性突发事件演化博弈环境污染经济新常态

Preparation of hydrophobic transparent paper via using polydimethylsiloxane as transparent agent

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Journal of Bioresources and Bioproducts 2020年第1期5卷 37-43页

作者： Feixiang Guan Zhaoping Song Furong Xin Huili Wang dehai Yu Guodong Li Wenxia Liu State Key Laboratory of Biobased Material and Green Papermaking Qilu University of TechnologyShandong Academy of SciencesJinan 250353China

Transparent paper with good hydrophobicity and flexibility was expected to act as an alternative substrate in fabrication of flexible ***,conventional paper made of cellulose fibers was opaque and hydrophilic without undergoing special ***,cellulose fiber paper was treated by impregnating with hydrolyzed tetraethyl orthosilicate(TEOS)followed by coating with hydrophobic polydimethylsiloxane(PDMS)to prepare hydrophobic transparent *** results showed that silica nanoparticles produced by the TEOS hydrolysis improved the paper transparency to some extent,increased the paper thermal stability,but still remained the hydrophilicity of *** the paper was further coated with the PDMS and the PDMS was consolidated,the paper became clearly transparent and *** processed paper had a transmittance of more than 90%at 550 *** water contact angle of the paper reached about 110°.This work provided a new approach for the fabrication of hydrophobic transparent paper with conventional cellulose fiber paper.

关键词： Transparent paper Cellulose fiber paper Hydrophobicity Tetraethyl orthosilicate(TEOS) Polydimethylsiloxane

Secondary Metabolites of a Deep Sea Derived Fungus Aspergillus versicolor CXCTD-06-6a and Their Bioactivity

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Journal of Ocean University of China 2014年第4期13卷 691-695页

作者： KONG Xianglan CAI Shengxin ZHU Tianjiao GU Qianqun LI dehai LUAN Yepeng Key Laboratory of Marine Drugs of Chinese Ministry of Education School of Medicine and Pharmacy Ocean University of China

In order to obtain novel secondary metabolites, a deep sea inhabiting fungus Aspergillus versicolor CXCTD-06-6a was investigated. One new diketopiperazine brevianamide W(1a), as well as five known diketopiperazine alkaloids, diketopiperazine V(1b), brevianamide Q(2), brevianamide R(3), brevianamide K(4), and brevianamide E(5), were isolated from the Et OAc extract of the fermentation broth. Their structures were elucidated by spectroscopy techniques(NMR, MS). The six compounds exhibited moderate radical scavenging activity against DPPH with clearance ratio of 55.0%(1a and 1b), 53.7%(2), 46.2%(3), 61.4%(4) and 19.3%(5) at a concentration of 13.9 μmol L-1, respectively; while the positive control ascorbic acid showed a ratio of 70.3% at the concentration of 28.4 μmol L-1.

关键词： deep sea fungus secondary metabolite diketopiperazine

A Ceph-based storage strategy for big gridded remote sensing data

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Big Earth Data 2022年第3期6卷 323-339页

作者： Xinyu Tang Xiaochuang Yao Diyou Liu Long Zhao Li Li dehai Zhu Guoqing Li College of Land Science and Technology China Agricultural UniversityBeijingChina Key Laboratory of Remote Sensing for Agri-Hazards Ministry of Agriculture and Rural AffairsBeijingChina Aerospace Information Research Institute Chinese Academy of SciencesBeijingChina School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijingChina

When using distributed storage systems to store gridded remote sensing data in large,distributed clusters,most solutions utilize big table index storage ***,in practice,the performance of big table index storage strategies degrades as scenarios become more complex,and the reasons for this phenomenon are analyzed in this *** improve the read and write performance of distributed gridded data storage,this paper proposes a storage strategy based on Ceph *** strategy encapsulates remote sensing images in the form of objects through a metadata management strategy to achieve the spatiotemporal retrieval of gridded data,finding the cluster location of gridded data through hash-like *** method can effectively achieve spatial operation support in the clustered database and at the same time enable fast random read and write of the gridded *** write and spatial query experiments proved the feasibility,effectiveness,and stability of this *** experiments prove that the method has higher stability than,and that the average query time is 38%lower than that for,the large table index storage strategy,which greatly improves the storage and query efficiency of gridded images.

关键词： Gridded images distributed storage system metadata management Ceph remote sensing

Preparation of alumina supported on carbon nano-tubes and its application in fluoride adsorption from an aqueous solution

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Chinese Science Bulletin 2002年第9期47卷 722-724页

作者： WANG Shuguang LI Yanhui ZHAO Dan XU Cailu LUAN Zhaokun LIANG Ji WU dehai State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Department of Mechanical Engineering State Key Laboratory of Automotive Safety and EnergyTsinghua UniversityBeijing 100084China Department of Chemistry Northeast UniversityShenyang 110004China

A novel material, alumina supported on carbon nanotubes (Al2O3/CNT), was prepared from carbon nano-tubes and A1(NO3)3. X-ray diffraction (XRD) spectra demonstrate that alumina is amorphous, and scanning electron microscope (SEM) images show that CNT and alumina are homogeneously mixed. Furthermore, the fluoride adsorption behavior on the surface of Al2O3/CNT has been investigated and compared with other adsorbents. The results indicate that Al2O3/CNT has a high adsorption capacity, with a saturation adsorption capacity of 39.4 mg/g. It is also found that the adsorption capacity of Al2O3/CNT is 3.0-4.5 times that of γ-Al2O3 while almost equal to that of IRA-410 polymeric resin at 25°C . The adsorption isotherms of fluoride on Al2O3/CNT fit the Freundlich equation well, and optimal pH ranging from 5.0 to 9.0.

关键词： carbon nanotube alumina fluoride removal composite material.