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Reagentless biosensor based on layer-by-layer assembly of functional multiwall carbon nanotubes and enzyme-mediator biocomposite

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第6期12卷 468-476页

作者： Xing-hua ZHOU Feng-na XI Yi-ming ZHANG xian-fu lin Department of Chemistry Zhejiang University Hangzhou 310027 China

A simple and controllable layer-by-layer （LBL） assembly method was proposed for the construction of reagentless biosensors based on electrostatic interaction between functional multiwall carbon nanotubes （MWNTs） and enzyme-mediator biocomposites. The carboxylated MWNTs were wrapped with polycations poly（allylamine hydrochloride）（PAH） and the resulting PAH-MWNTs were well dispersed and positively charged. As a water-soluble dye methylene blue （MB） could mix well with horseradish peroxidase （HRP） to form a biocompatible and negativelycharged HRP-MB biocomposite. A （PAH-MWNTs/HRP-MB）, bionanomultilayer was then prepared by electrostatic LBL assembly of PAH-MWNTs and HRP-MB on a polyelectrolyte precursor film-modified Au electrode. Due to the excellent biocompatibility of HRP-MB biocomposite and the uniform LBL assembly, the immobilized HRP could retain its natural bioactivity and MB could efficiently shuttle electrons between HRP and the electrode. The incorporation of MWNTs in the bionanomultilayer enhanced the surface coverage concentration of the electroactive enzyme and increased the catalytic current response of the electrode. The proposed biosensor displayed a fast response （2 s） to hydrogen peroxide with a low detection limit of 2.0× 10^-7 mol/L （S/N=3）. This work provided a versatile platform in the further development of reagentless biosensors.

关键词： Reagentless biosensor Layer-by-layer assembl Horseradish peroxidase-methylene blue (HRP-MB) biocomposite functional multiwall carbon nanotubes Hydrogen peroxide

CHEMOENZYMATIC SYNTHESIS OF BIODEGRADABLE POLY(1’-O-VINYLADIPOYL-SUCROSE)

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Chinese Journal of Polymer Science 2002年第6期20卷 579-584页

作者： De-shui Lu Qi Wu xian-fu lin Department of Chemistry Zhejiang University Hangzhou 310027, China Department of Chemistry Zhejiang University Hangzhou 310027

A novel polymer containing the sucrose group was synthesized by radical polymerization from an enzymatically prepared monomer, 1'-O-vinyladipoyl-sucrose (VAS). Transesterification reaction of sucrose with divinyl adipate in anhydrous pyridine catalyzed by an alkaline protease from Bacillus subtilis at 60degreesC for 7 days gave VAS (yield 55%) without any blocking/deblocking steps. The vinyl sucrose ester could be polymerized with potassium persulfate and H2O2 as initiator to give poly(1'-O-vinyladipoyl-sucrose) with M-n = 33,000 and M-w = 53,200, M-w/M-n = 1.61. The polymer was biodegradable. After 6 days in aqueous buffer (pH 7), this alkaline protease could degrade poly(1'-O-vinyladipoyl-sucrose) to M. of ca. 1080, M-w/M-n = 3.30 (37degreesC), and M-n of ca. 5200, M-w/M-n = 2.44 (4degreesC). The polymer containing the sucrose branch would be a functional material in various application fields.

关键词： divinyladipate sucrose alkaline protease polymerization biodegradation

Enzymatic Regioselective Synthesis of Vinyl Lactose Ester and Its Chemical Polymerization

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Chinese Chemical Letters 2002年第5期13卷 416-419页

作者： Qi WU Jian Yue FENG Chen Guo FENG De Shui LU xian fu lin Department of Chemistry Zhejiang UniversityHangzhou 310027

Transesterification reaction of lactose with divinyladipate in pyridine catalyzed by an alkaline protease from Bacillus subtilis at 50C for 3 days gave 6-O-vinyladipoyl-lactose (yield 35%). Poly(6-O-vinyladipoyl-lactose) with Mn = 21,200, Mw = 32,900, Mw/Mn = 1.56 could be obtained by chemical polymerization. Poly(vinyl alcohol) containing lactose branch was biodegradable. After 6 days in aqueous buffer (PH 7), this alkaline protease could degrade the polymer to an Mn of ca. 2100, Mw/Mn = 2.56.

关键词： Regioselectivity vinyl ester lactose alkaline protease polymerization.

Enzyme-catalyzed Transesterification of Unusual Substrate: Synthesis of Acyclovir and L-ascorbic Acid (Vitamin C) Vinyl Esters

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Chinese Chemical Letters 2003年第2期14卷 163-166页

作者： Xing Tao XUE De Shui Lu Zhi Chun CHEN Qi WU Ying CAI xian fu lin Department of Chemistry Zhejiang UniversityHangzhou 310027

The synthesis of acyclovir and L-ascorbic acid with divinyladipate was performed with alkaline protease from Bacillus subtilis and lipase from Lipozyme (immobilized from Mucor miehei) in different anhydrous organic so... 详细信息

关键词： Alkaline protease lipase transesterification acyclovir vitamin C vinyl ester.

Engineering high-performance dielectric chiral shells with enhanced chiral fields for sensitive chiral biosensor

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Rare Metals 2024年第3期43卷 1197-1206页

作者： Yi-Fan Wang Shan-Shan Huang Zhen-Dong Dai Shi-lin xian Xuan-Nan Wu fu-Hua Gao Yi-Dong Hou College of Physics Sichuan UniversityChengdu610065China Graduate School of Sichuan University Sichuan UniversityChengdu610065China

Chiral metamaterials have been a topic of significant research interest in recent years due to their potential for various applications in nanophotonic devices and chiral ***,the intrinsic Ohmic loss in surface plasmonic resonance has limited their practical use,resulting in large light dissipation and weak chiroptical ***,we report on the development of high-performance dielectric chiral shells(DCS)through a two-step Si deposition process on a self-assembled microsphere *** form DCS sample completely oyercomes the cancelation effect originated from the disorder property of the micro-sphere monolayer in macroscale,and at a wavelength of approximately 710 nm,the measured optimal chiral signal(g-factor)and transmittance can reach up to 0.7 and 0.3,*** strong chiroptical effect comes from the asymmetric circular displacement currents(i.e.,magnetic modes)enabled by the specific shell *** chiral shell geometry,electromagnetic properties,sensor sensitivity of chiral molecules and figure of merit are systematically *** DCSs demonstrate highly sensitive detection of chiral biomolecules owing to their easily accessible geometry and enhanced uniform chiral field.

关键词： Dielectric chiral shells(DCS) Si deposition Magnetic resonance Highly sensitive sensor Chiral field

A Survey on Distributed Network Localization from a Graph Laplacian Perspective

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Journal of Systems Science & Complexity 2024年第1期37卷 273-293页

作者： HAN Zhimin lin Zhiyun fu Minyue Artificial Intelligence Institute School of AutomationHangzhou Dianzi UniversityHangzhou 310018China Shenzhen Key Laboratory of Control Theory and Intelligent Systems School of System Design and Intelligent ManufacturingSouthern University of Science and TechnologyShenzhen 518055China Peng Cheng Laboratory Shenzhen 518000China

Network localization serves as a fundamental component for enabling various position based operations in multi-agent systems,facilitating tasks like target searching and formation control by providing accurate position information for all nodes in the *** localization focuses on the challenge of determining the positions of nodes within a network,relying on the known positions of anchor nodes and internode relative *** the past few decades,distributed network localization has garnered significant attention from *** paper aims to provide a review of main results and advancements in the field of distributed network localization,with a particular focus on the perspective of graph *** to its favorable characteristics,graph Laplacian unifies various network localization,even when dealing with diverse types of internode relative measurements,into a unified protocol framework,which can be constructed by a linear method and ensure the global convergence.

关键词： Distributed network localization graph Laplaian sensor network

Differences and identification on multi-time hydrocarbon generation of carboniferous-permian coaly source rocks in the Huanghua Depression,Bohai Bay Basin

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Petroleum Science 2024年第2期21卷 765-776页

作者： Jin-Jun Xu xian-Gang Cheng Shu-Nan Peng Jun-Cai Jiang Qi-Long Wu Da Lou fu-Qi Cheng La-Mei lin National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShandongChina PetroChina Dagang Oilfield Company Tianjin300280China

Coal is a solid combustible mineral,and coal-bearing strata have important hydrocarbon generation potential and contribute to more than 12%of the global hydrocarbon ***,the deposition and hydrocarbon evolution process of ancient coal-bearing strata is characterized by multiple geological times,leading to obvious distinctions in their hydrocarbon generation potential,geological processes,and production,which affect the evaluation and exploration of hydrocarbon resources derived from coaly source rocks *** study aimed to identify the differences on oil-generated parent macerals and the production of oil generated from different coaly source rocks and through different oil generation *** with the analysis of previous tectonic burial history and hydrocarbon generation history,high-temperature and high-pressure thermal simulation experiments,organic geochemistry,and organic petrology were performed on the Carboniferous-Permian(C-P)coaly source rocks in the Huanghua Depression,Bohai Bay *** oil-generated parent macerals of coal's secondary oil generation process(SOGP)were mainly hydrogen-rich collotelinite,collodetrinite,sporinite,and cutinite,while the oil-generated parent macerals of tertiary oil generation process(TOGP)were the remaining small amount of hydrogen-rich collotelinite,sporinite,and cutinite,as well as dispersed soluble organic matter and unexhausted residual *** with coal,the oil-generated parent macerals of coaly shale SOGP were mostly sporinite and *** part of hydrogen-poor vitrinite,lacking hydrocarbon-rich macerals,and macerals of the TOGP,in addition to some remaining cutinite and a small amount of crude oil and bitumen from SOGP contributed to the oil *** results indicated that the changes in oil yield had a good junction between SOGP and TOGP,both coal and coaly shale had higher SOGP aborted oil yield than TOGP starting yield,and coaly shale TOGP peak oil yield was low

关键词： Thermal simulation Multi-time oil generation processes Coaly source rock Carboniferous-permian Huanghua Depression

Elastohydrodynamic Lubrication Interface Stiffness and Damping Considering Asperity Lateral Contact

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Acta Mechanica Solida Sinica 2024年第1期37卷 109-123页

作者： Zhiqiang Gao Yu Zhang xian Wei Yanfang Zhu Lixia Peng Weiping fu Wen Wang School of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048China School of Intelligent Manufacturing Panzhihua UniversityPanzhihua 617000China Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Light Chemical TechnologyYibin 644002China School of Mechanical Engineering Anyang Institute of TechnologyAnyang 455099China

Elastohydrodynamic lubrication(EHL)point contact occurs between two rough surfaces at the mesoscopic level,while the interaction of rough surfaces involves contact between asperities at the microscale *** most cases,the contact between asperities within an interface takes the form of lateral contact rather than peak *** devoid of contact asperities are filled with lubricating ***,conventional models often oversimplify lateral contact forms as interactions between asperities and a smooth,rigid *** simplifications fail to accurately represent the true contact conditions and can lead to inaccuracies in the analysis of EHL’s contact *** address this issue,we have developed a novel EHL interface model comprising two rough *** model allows us to explore the influence of asperity height,contact angle,and contact azimuth angle on EHL interface performance.

关键词： EHL interface Asperity lateral contact Contact stiffness Damping

Intermediate-mass black holes in Green pea galaxies(IMBH-GP) I:A candidate sample from LAMOST and SDSS

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 151-165页

作者： Ruqiu lin Zhen-Ya Zheng Fang-Ting Yuan Jun-xian Wang Chunyan Jiang Ning Jiang lingzhi Wang linhua Jiang xiang Ji Shuairu Zhu Xiaodan fu Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of Sciences School of Astronomy and Space Sciences University of Chinese Academy of Sciences CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of China Chinese Academy of Sciences South America Center for Astronomy (CASSACA) National Astronomical ObservatoriesChinese Academy of Sciences CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences Kavli Institute for Astronomy and Astrophysics Peking University Department of Astronomy School of PhysicsPeking University

The scaling relation of central massive black holes（MBHs） and their host galaxies is well-studied for supermassive BHs(SMBHs,MBH≥10～6M⊙).However,this relation has large uncertainties in the mass range of the intermediate-mass BHs(IMBHs,MBH～10～3-10～6M⊙).Since Green pea（GP） galaxies are luminous compact dwarf galaxies,which may be likely to host less massive SMBHs or even IMBHs,we systematically search for MBHs in a large sample of 2190 GP galaxies at zline width,BPT diagram,mid-infrared color,X-ray luminosity,and radio *** studies show that it is very promising to find IMBHs in GP galaxies,and the BH sample so obtained enables us to probe the connection between the MBHs and compact dwarf galaxies in the low-redshift Universe.

关键词： SMBHs IMBHs Green pea galaxies compact dwarf galaxies

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