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First record of the little fire ant,Wasmannia auropunctata(Hymenoptera:Formicidae),in Chinese mainland

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Journal of Integrative Agriculture 2022年第6期21卷 1825-1829页

作者： CHEN Si-qi ZHAO yi LU Yong-yue RAN Hao xu yi-juan Red Imported Fire Ant Research Center South China Agricultural UniversityGuangzhou 510642P.R.China

In January 2022,we received ant specimens collected from three field colonies from Shantou City,Guangdong Province,*** were identified as the little fire ant,Wasmannia auropunctata,through morphological and molecular *** auropunctata is listed as one of the 100 most dangerous invasive species by the International Union for Conservation of Nature(IUCN)and has spread from its native range in South America to every continent except *** analysis of mitochondrial cytochrome c oxidase subunit I(COI)in nine specimens of *** found that they had a close genetic relationship with specimens from *** study represents the first formal record of the establishment of *** outdoor in Chinese ***,the invasion stage and occurrence degree of *** in China are not clear to *** implementation of quarantine measures,investigation of the occurrence and distribution,and development of monitoring and control strategies are needed to actively respond to the threat posed by this highly invasive ant.

关键词： little fire ant morphological identification mitochondrial cytochrome c oxidase subunit I

A new radical way to N,N-dimethylaniline hydroperoxide (DMAHP) and its application in organic synthesis

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Chinese Chemical Letters 2007年第7期18卷 807-810页

作者： yi xu Shi Lei Zhang Wen Hu Duan Shanghai Institute of Materia Medica Shanghai Institutes of Biological Sciences Chinese Academy of SciencesGraduate School of the Chinese Academy of Sciences Shanghai 201203 China

N,N-Dimethylaniline hydroperoxide was obtained when treating N,N-dimethylaniline with NHPI/Co（OAc）2/O2 via a radical reaction mechanism. This intermediate has potential application in the synthesis of some important... 详细信息

关键词： Aerobic oxidation NHPI N,N-Dimethylaniline

Immobilization of acetylcholinesterase on functionalized SBA-15 mesoporous molecular sieve for detection of organophosphorus and carbamate pesticide

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Chinese Chemical Letters 2018年第9期29卷 1387-1390页

作者： yin Rui Xiaomei Wu Baodi Ma yi xu School of Chemical and Environmental Engineering Shanghai Institute of Technology

The immobilization of acetylcholinesterase （ACHE） on amino functionalized SBA-15 mesoporous sieves （NH2-SBA-15） was explored for detection of organophosphorus and carhamate pesticides. Several methods have been studied and the ＂adsorption-crosslinking＂ is found to be the best one. Firstly, AChE and bovine serum albumin （BSA） were adsorbed in turn on the surface of NH2-SBA-15 by electrostatic adsorption, and then glutaraldehyde was added for cross-linking the amino group of AChE. The NH2-SBA- 15 showed around 95% immobilization efficiency and the specific activity of immobilized AChE （ACHE- NH2-SBA-15） reached 130% relative to free AChE under optimal immobilization conditions. It was found AChE-NH2-SBA-15 retained 94.0% and 82.8% of its initial activity after 60days at 4℃ and 25℃, respectively. It remained 55.0% of its initial activity after 6 times recycling. During the detection of pesticide, the AChE-NH2-SBA-15 showed wider linear range and much lower limit of detection compared with free ACHE. The current method showed good recovery （93.8%-109.3%） and low RSD （〈5%） for both standard solution and real vegetable samples of Carbaryl and Trichlorfon. It was believed that AChE-NH2- SBA- 15 could be exploited as a fast, sensitive and low-cost biocatalyst towards the detection of pesticides residues which could be stored at room temperature for a long time.

关键词： Acetylcholinesterase Immobilization Adsorption-crosslinking Mesoporous SBA-15 molecular sieve Pesticide residues detection

Cylindrical vector beams reveal radiationless anapole condition in a resonant state

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Opto-Electronic Advances 2022年第4期5卷 69-75页

作者： Yudong Lu yi xu xu Ouyang Mingcong Xian Yaoyu Cao Kai Chen Xiangping Li Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications Institute of Photonics TechnologyJinan UniversityGuangzhou 510632China Department of Electronic Engineering College of Information Science and TechnologyJinan UniversityGuangzhou 510632China

Nonscattering optical anapole condition is corresponding to the excitation of radiationless field distributions in open resonators,which offers new degrees of freedom for tailoring light-matter *** mechanisms for achieving such a condition relies on sophisticated manipulation of electromagnetic multipolar moments of all orders to guarantee superpositions of suppressed moment strengths at the same *** contrast,here we report on the excitation of optical radiationless anapole hidden in a resonant state of a Si nanoparticle utilizing a tightly focused radially polarized(RP)*** coexistence of magnetic resonant state and anapole condition at the same wavelength further enables the triggering of resonant state by a tightly focused azimuthally polarized(AP)beam whose corresponding electric multipole coefficient could be *** a result,high contrast inter-transition between radiationless anapole condition and ideal magnetic resonant scattering can be achieved experimentally in visible *** proposed mechanism is general which can be realized in different types of *** results showcase that the unique combination of structured light and structured Mie resonances could provide new degrees of freedom for tailoring light-matter interaction,which might shed new light on functional meta-optics.

关键词： apole multipole decomposition all-dielectric nanoparticles

Microstructural Characterization of Spray Formed FGH4095 Superalloy During Hot Deformation

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Journal of Iron and Steel Research International 2013年第7期20卷 57-62页

作者： xu yi SHU Qin GUO Biao SUN Chuan-shui School of Materials Science and Engineering Southwest Jiaotong University

In order to study the hot workability and to optimize the processing parameters for spray formed FGH4095 superalloy, thermal compression tests for spray formed FGH4095 superalloy have been finished by using a Gleeble 1500 thermal simulated test machine at the strain rates of 0.01-10.0 s 1 and temperatures of 1 050-1 140 ℃. The effects of strain rate and deformation temperature on the true stress-true strain curves and microstructure evolution were investigated. The results show that the generation of dynamic recrystallization （DRX） depends sensitively on deformation temperature. When the temperature was lower than 1080 ~C, long and＂ narrow necklace grains were shown in the microstructure. When the temperature increased to 1 140 ℃, new recrystallization grains were genera-ted. The size and shape of X＇ precipitates in the grains have a very important effect as factors of hindering sufficient migration of dislocations on plastic deformation. The result of thermal processing map is in accord with the micro-structure observation, and the best material thermal processing temperature is above 1 128 ℃.

关键词： spray forming microstructure FGH4095 superalloy dynamic recrystallization dislocation thermalprocessing map

Lubrication in Hot Tube Extrusion of Superalloys and Ti Alloys

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Journal of Materials Science & Technology 2001年第1期17卷 113-114页

作者： Shihong ZHANG yi xu Yangling SHANG Ke YANG Zhongtang WANG Institute of Metal Research Chinese Academy of SciencesShenyang 110015China

Tubular products made of superalloys and titanium alloys usually work in high temperature environment and applied heavy loading. Hot extrusion is the best technology to form tubular billets with fine microstructures and good mechanical properties. Lubrication is one of the key techniques in hot extrusion, glass lubricants are most suitable for hot extrusion. Lubrication technique in hot extrusion is dealt with in this paper, the lubrication principle of hot tube extrusion is presented. Experiments of glass lubricated backward tube extrusion of titanium alloys and forward tube extrusion of superalloys are also discussed.

关键词： hot extrusion titanium alloys mechanical properties high temperature environment and key techniques hot tube

Preparation of Exfoliated Low-density Polyethylene/Montmorillonite Nanocomposites Through Melt Extrusion

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Chemical Research in Chinese Universities 2006年第3期22卷 383-387页

作者： YANG Hong-mei SONG yi-hu xu Bo ZHENG Qiang Department of Polymer Science ＆ Engineering Key Laboratory of Macromolecule Synthesis and Functionalization of MOE Zhejiang University Hangzhou 310027 P. R. China

The effects of ethylene vinyl acetate copelymer （EVA） as a compatibilizer on the dispersion of organically modified montmorillonite（org-MMT） into low-density polyethylene（LDPE） during melt extrusion compounding were studied. The X-ray diffraction patterns reveal that as compared with LDPE, EVA can intercalate more easily into the interlay gallery of org-MMT when the composites contain a low org-MMT content. Exfoliated LDPE/org-MMT nanocompesites in the presence of an EVA compatibilizer could be prepared by using a two-step melt compounding technique with a twin-screw extruder.

关键词： Polyethylene Montmorillonite Nanocompesite Intercalation Exfoliation

Design,preparation,and structure of particle preforms for Si_3N_(4(P))/Si_3N_4 radome composites prepared using chemical vapor infiltration process

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Journal of University of Science and Technology Beijing 2008年第1期15卷 62-66页

作者： Yongsheng Liu Laifei Cheng Litong Zhang Yongdong xu yi Liu National Key Laboratory of Thermostructure Composite Materials Northwestern Polytechnical University Xi＇an 710072 China

A particle preform was designed and prepared by conglomerating and cold-pressed process, which was condensed by chemical vapor infiltration （CVI） process to fabricate silicon nitride particles reinforced silicon nitride composites. The conglomerations are of almost sphericity after conglomerated. There are large pores among the conglomerations and small pores within themselves in the preform according to the design and the test of pore size distribution. The pore size of the preform is characterized by a double-peak distribution. The pore size distribution is influenced by conglomeration size. Large pores among the conglomerations still exist after infiltrated Si3N4 matrix. The conglomerations, however, are very compact. The CVI Si3N4 looks like cauliflowershaped structure. 2008 University of Science and Technology Beijing. All rights reserved.

关键词： silicon nitride particle preform design microstructure chemical vapor infiltration (CVI)

NOVEL HYPERBRANCHED POLY(AMINE-ESTER) FILMS: PREPARATION, CHARACTERIZATION AND PROPERTIES

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Chinese Journal of Polymer Science 2006年第3期24卷 291-297页

作者： Xiu-zhen Wei 朱宝库 Ling Xiao You-yi xu Institute of Polymer Science Zhejiang University Hangzhou 310027 China

Crosslinked film of hyperbranched poly（amine-ester）（HPAE） was prepared by crosslinking its terminal hydroxyl groups with glutaraldehyde （GA）. Atom force microscope （AFM） and scanning electron microscope （SEM） reveals that they have smooth surfaces, dense and homogenous matrices. It was found that the water static contact angle is smaller than 41.7°, the tensile strength is higher than 8.9 MPa, the elongation at break is higher than 5.1%, the swelling degree is higher than 42% in water, and the Bovine hemoglobin （Hb） adsorption is relatively low. These results indicate that the crosslinked HPAE films might have some potential applications in many areas.

关键词： Crosslinking Hyperbranched poly(amine-ester) Glutaraldehyde Films.