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Chinese Chemical Letters 2022年第11期33卷 4750-4755页

作者： Ze Hu Yaqun Xu Hao Wang gao-chao Fan Xiliang Luo Shandong Key Laboratory of Biochemical Analysis College of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

Accurate detection of important biomarkers with ultra-low levels in complex biological matrix is one of the frontier scientific issues because of possible signal interference of potential reductive agents and protein ***,a self-powered anti-interference photoelectrochemical(PEC)immunosensor was explored for sensitive and specific detection of model target of cardiac troponinⅠ(cTnI).Specifically,a novel ternary heterojunction served as the photocathode to offer a remarkable current output and a zwitterionic peptide was introduced to build a robust antifouling ***(CIS)film with porous network nanostructure was first prepared and then modified in order with ZnInS(ZIS)nanocrystals and Au nanoparticles to fabricate the Au/ZIS/CIS heterojunction *** capture cTnI antibody(Ab)was immobilized,the zwitterionic peptide KAEAKAEAPPPPC was then anchored to compete the *** elaborated PEC immunosensor exhibited high sensitivity for target cTnI antigen(Ag)detection,with good anti-interference against reductive agents and nonspecific *** integration strategy of heterojunction photocathode with zwitterionic peptide provides a new sight to develop advanced PEC immunosensors applying in practical biosamples.

关键词： Photoelectrochemistry Immunoassay Zwitterionic peptide Photocathode Anti-interference

Characterization of a Novel Mesophilic Bacterial Amylase Secreted by ZW2531-1, a Strain Newly Isolated from Soil

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Chemical Research in Chinese Universities 2009年第2期25卷 198-202页

作者： WANG Yang LI Fan gao chao-hui ZHANG Ying-Jiu Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education Jilin University Changchun 130021 P. R. China

A novel mesophilic bacterial amylase, named oligosaccharide-producing multifunctional amylase（OPMA）, was discovered and characterized. OPMA is an extracellular enzyme secreted by ZW253 1-1, a strain newly isolated from Chinese soil. It could be purified to homogeneity from the culture supernatant of ZW2531-1 by 30%-60% saturated ammonium sulfate precipitation, followed by twice Sephadex gel filtration chromatography. OPMA is a 66 kDa protein based on SDS-PAGE and has an isoelectric point（p/） at pH=5.3 by Isoelectric focusing electrophoresis（WE）. It only catalyzes the degradation of starch, rather than other alpha-l,4- and/or 1,6-glucan polysaccbarides such as fl-cyclomaltodextrin and pullulan. OPMA degraded starch to produce several oligosccharides including maltose, maltotriose, and isomaltotriose as the major end-products, and perhaps other oligosaccharides such as isomalto- tetraose, rather than glucose. OPMA exhibited optimal catalytic activity at a reaction temperature of 50 ℃ and pH=6.0, as determined by orthogonal test. Under the optimal reaction conditions, purified OPMA bad a specific activity of 13.75 U/rag. These findings suggest that OPMA could be used for the production of some oligosaccharides beneficial to the food industry and medicine.

关键词： Amylase Bacterium Oligosaccharide Purification Starch

pH-responsive poly(2-diethylaminoethyl methacrylate)-functionalized multiwalled carbon nanotubes

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Chinese Science Bulletin 2005年第20期50卷 2276-2280页

作者： LI Wenwen KONG Hao gao chao YAN Deyue College of Chemistry and Chemical Engineering Shanghai Jiaotong University Shanghai 200240 China

Poly(2-diethylaminoethyl methacrylate) (PDEAEMA)-coated multiwalled carbon nanotubes (MWNT- PDEAEMA) were successfully prepared by MWNT-surface initiated atom transfer radical polymerization (ATRP). The obtained MWNT-PDEAEMA nanocylinders have a core of MWNT and a shell of PDEAEMA and this core-shell struc- ture was confirmed by TEM observations. The UV-Vis and AFM measurements showed that the MWNT-PDEAEMA exhibited obvious pH sensitivity. The solubility of PDEAEMA-coated MWNT dramatically decreased when pH increased to ca. 7.0. Because of the giant molecular weight of the molecular hybrids and local high density of polymeric grafts linked onto MWNTs, the resulting MWNT-PDEAEMA nanocomposites are easier to aggregate, or more sensitive to pH, as compared with the neat PDEAEMA.

关键词：碳纳米管 MWNT-PDEAEMA 聚乙烯 PH灵敏度可溶性

Improved hydrogen storage properties of LiBH4 confined with activated charcoal by ball milling

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Rare Metals 2019年第4期38卷 321-326页

作者： He Zhou Xin-Hua Wang Hai-Zhen Liu Shi-chao gao Mi Yan State Key Laboratory of Silicon Materials School of Materials Science & Engineering Zhejiang University Hangzhou 310027 China State Key Laboratory of Advanced Transmission Technology Global Energy Interconnection Research Institute State Grid Corporation of China Beijing 102209 China

In order to enhance the hydrogen storage properties of LiBH4,activated charcoal (AC) was used as the scaffold to confine LiBH4 in this *** milling was used to prepare LiBH4/AC *** results show that dehydrogenation properties of ball-milled LiBH4/AC (LiBH4/AC-BM) are greatly improved compared with that of pristine LiBH4,ball-milled LiBH4 (LiBH4-BM) and hand-milled LiBH4/AC (LiBH4/AC-HM).The onset dehydrogenation temperature of LiBH4 for LiBH4/AC-BM is around 160 ℃,which is 170 ℃ lower than that of pristine *** around 400 ℃,LiBH4/AC-BM finishes the dehydrogenation with a hydrogen capacity of 13.6 wt%,which is approximately the theoretical dehydrogenation capacity of pure LiBH4 (13.8 wt%),while the dehydrogenation processes for LiBH4-BM and LiBH4/AC-BM do not finish even when they were heated to 600 ℃.The isothermal dehydriding measurements show that it takes only 15 min for LiBH4/AC-BM to reach a dehydrogenation capacity of 10.1 wt% at 350 ℃,whereas the pristine LiBH4 and the LiBH4/AC-HM release hydrogen less than 1 wt% under the same *** dehydrogenation process and the effect of AC were discussed.

关键词： Hydrogen storage properties Hydrogen storage materials Lithium borohydride Activated charcoal

Microwave-assistant Syntheses, Crystal Structures and Safener Activities of Two Substituted Phenyl Isoxazole Derivatives

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Chinese Journal of Structural Chemistry 2021年第9期40卷 1231-1237,1111页

作者： gao Ying-chao SHAO Xin-Xin FU Ying College of Arts and Sciences Northeast Agricultural UniversityHarbin 150030China

Two novel substituted phenyl isoxazole benzoxazine formamide derivatives were designed and synthesized with substituted o-aminophenol,1,2-dibromoethane and different phenyl substituted isoxazole formyl chloride as the raw materials via microwave assistant *** target compounds were characterized by IR,^(1)H NMR,^(13)C NMR and *** single-crystal structures were further determined by X-ray diffraction.3-(2’-Chloro-6’-fluoro-phenyl)-4-(2’,3’-dihydro-1’,4’-benzoxazine)-5-methyl-isoxazole formamide (4a) crystallizes in orthorhombic system,P2_(1) space group with a=8.9414(18),b=10.834(2),c=17.706(4)A,V=1715.1(6)A^(3),D_(c)=1.444 Mg/m^(3),Z=4,F(000)=768,μ(Mo Kα)=0.255 mm^(-1),R=0.0406 and wR=0.1171.3-Phenyl-4-(6-methyl-2’,3’-dihydro-1’,4’-benzoxazine)-5-methyl-isoxazole formamide (4b) is of triclinic system,space group PI with a=7.7659(16),b=8.3626(17),c=13.484(3)A,α=76.04(3)°,β=100.63(3)°,γ=82.01(3)°,V=841.6(3)A^(3),D_(c)=1.319 Mg/m^(3),Z=2,F(000)=352,μ(Mo Kα)=0.090 mm^(-1),R=0.0672 and wR=*** crystals are packed through C–H···O hydrogen bonding *** is C–H···F hydrogen bond between 4a molecules,and C–H···N between 4b *** results showed that compounds 4a and 4b exhibited detoxification on maize and restored maize growth index.

关键词： isoxazole benzoxazine formamide microwave-assistant synthesis single-crystal structure safener activity

Survey of multi-channel MAC protocols for IEEE 802.11-based wireless Mesh networks

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The Journal of China Universities of Posts and Telecommunications 2011年第2期18卷 33-44页

作者： LEI Hong-jiang gao chao GUO Yong-cai ZHANG Zhi-zhong College of Optoelectronic Engineering Chongqing University Chongqing 400050 China School of Commtmication and Information Engineering Chongqing University of posts and telecommunications Chongqing 400065 China

This paper reviews multi-channel media access control（MAC） protocols based on IEEE 802.11 in wireless Mesh networks（WMNs）.Several key issues in multi-channel IEEE 802.11-based WMNs are introduced and typical solutions proposed in recent years are classified and discussed in *** experiments are performed by network simulator version 2（NS2） to evaluate four representative algorithms compared with traditional IEEE *** results indicate that using multiple channels can substantially improve the performance of WMNs in single-hop scenario and each node equipped with multiple interfaces can substantially improve the performance of WMNs in multi-hop scenario.

关键词： wireless Mesh networks multi-channel protocol medium access control layer IEEE 802.11

A RESEARCH TO HIGH-PERFORMANCE MULTI-LEVEL SINGLE-PHASE AC/DC POWER FACTOR CORRECT SWITCHING CONVERTER

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Journal of Electronics(China) 2008年第5期25卷 716-720页

作者： gao chao Department of Electronic Engineering Shenzhen Institute of Information Technology Shenzhen 518029 China

This letter studies and analyzes the working features of main circuit of tri-level boost Power Factor Correct(PFC) converter and the advantages of tri-level switch converter in aspects of bearing high-voltage of power components,overall system loss and magnetic component selection based upon the single-level boost PFC switch ***,relying on the application of mi-croprocessor in power converter technology and DSP(Digital Signal Processing) chip's strong cal-culating capacity,the letter presents the adoption of modified scheme of tri-level boost PFC converter under the control of predictive control ***,the operating principle and control method are specified,the results of circuit test and analysis are provided and the advantages of pre-dictive control technology-based multi-level boost PFC converter is verified.

关键词： Multi-level Power Factor Correct (PFC) Digital Signal Processing (DSP) Converter Predictive control Microprocessor

Synergistic effect of Zr and Mo on precipitation and high-temperature properties of Al-Si-Cu-Mg alloys

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China Foundry 2024年第1期21卷 71-81页

作者： chao gao Bing-rong Zhang Yin-ming Li Zhi-ming Wang Xiang-bin Meng Faculty of Mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Hebei Ounai Machinery Mould Co.Ltd. Xingtai 054500HebeiChina

This study focuses on finding a solution to the sharp decline in mechanical properties of Al-Si-Cu-Mg alloys due to rapid coarsening of traditional intermediate phases at high temperature.A new type of modified al oy,to be used in automobile engines at high temperatures,was prepared by adding Zr and Mo into Al-Si-Cu-Mg *** synergistic effects of Zr and Mo on the microstructure evolution and high-temperature mechanical properties were *** show that the addition of Zr and Mo generates a series of intermetallic phases dispersed in the *** can improve the strength of the alloy by hindering dislocation movement and crack *** addition,some nano-strengthened phases show coherent interfaces with the matrix and improve grain *** addition of Mo greatly improves the heat resistance of the *** extremely low diffusivity of Mo enables it to improve the thermal stability of the intermetallic phases,inhibit precipitation during aging,reduce the size of the precipitates,and improve the heat resistance of the alloy.

关键词： Al-Si-Cu-Mg alloy high-temperature properties Zr-Mo-rich intermetallics nano-strengthening phases

A graphitized expanded graphite cathode for aluminum-ion battery with excellent rate capability

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Journal of Energy Chemistry 2022年第3期31卷 38-44,I0002页

作者： Xiaozhong Dong Hao Chen Haiwen Lai Liyong Wang Jiaqing Wang Wenzhang Fang chao gao MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringKey Laboratory of Adsorption and Separation Materials&Technologies of Zhejiang ProvinceZhejiang UniversityHangzhou 310027ZhejiangChina Department of Materials Engineering Taiyuan Institute of TechnologyTaiyuan 030008ShanxiChina Hangzhou gaoxi Technology Co.Ltd. Hangzhou 310000ZhejiangChina Hebei Normal University for Nationalities Chengde 067000HebeiChina

Aluminum-ion battery(AIB)is very promising for its safety and large current charge–***,it is challenging to build a high-performance AIB system based on low-cost materials especially cathode&*** the low-cost expanded graphite-triethylaminehydrochloride(EG-ET)system has been improved in cycle performance,its rate capability still remains a gap with the expensive graphene-alkylimidazoliumchloride AIB *** this work,we treated the cheap EG appropriately through an industrial high-temperature process,employed the obtained EG3K(treated at 3000℃)cathode with AlCl_(3)-ET electrolyte,and built a novel,high-rate capability and double-cheap AIB *** new EG3K-ET system achieved the cathode capacity of average 110 m Ah g^(-1)at 1 A g^(-1)with 18,000cycles,and retained the cathode capacity of 100 m Ah g^(-1)at 5 A g^(-1)with 27,500 cycles(fast charging of 72 s).Impressively,we demonstrated that a battery pack(EG3K-ET system,12 m Ah)had successfully driven the Model car running 100 m *** addition,it was confirmed that the improvement of rate capability in the EG3K-ET system was mainly derived by deposition,and its capacity contribution ratio was about 53.7%.This work further promoted the application potential of the low-cost EG-ET AIB system.

关键词： Aluminum-ion battery Expanded graphite Triethylamine hydrochloride

A Review on Graphene Oxide Two-dimensional Macromolecules: from Single Molecules to Macro-assembly

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Chinese Journal of Polymer Science 2021年第3期39卷 267-308,I0004页

作者： Wen-Zhang Fang Li Peng Ying-Jun Liu Fang Wang Zhen Xu chao gao Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

Graphene oxide(GO), which consists of two-dimensional(2 D) sp^(2) carbon hexagonal networks and oxygen-contained functional groups, has laid the foundation of mass production and applications of graphene materials. Made by chemical oxidation of graphite, GO is highly dispersible or even solubilized in water and polar organic solvents, which resolves the hard problem of graphene processing and opens a door to wet-processing of graphene. Despite its defects, GO is easy to functionalize, dope, punch holes, cut into pieces, conduct chemical reduction, form lyotropic liquid crystal, and assemble into macroscopic materials with tunable structures and properties as a living building block. GO sheet has been viewed as a single molecule, a particle, as well as a soft polymer material. An overview on GO as a 2 D macromolecule is essential for studying its intrinsic properties and guiding the development of relevant subjects. This review mainly focuses on recent advances of GO sheets, from single macromolecular behavior to macro-assembled graphene material properties. The first part of this review offers a brief introduction to the synthesis of GO molecules. Then the chemical structure and physical properties of GO are presented, as well as its polarity in solvent and rheology behavior. Several key parameters governing the ultimate stability of GO colloidal behavior, including size, p H and the presence of cation in aqueous dispersions, are highlighted. Furthermore, the discovery of GO liquid crystal and functionalization of GO molecules have built solid new foundations of preparing highly ordered, architecture-tunable, macro-assembled graphene materials, including 1 D graphene fibers, 2 D graphene films, and 3 D graphene architectures. The GO-based composites are also viewed and the interactions between these target materials and GO are carefully discussed. Finally, an outlook is provided in this field, where GO is regarded as macromolecules, pointing out the challenges and o

关键词： Graphene 2D macromolecules Macro-assembly