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Chinese Physics Letters 2019年第4期36卷 75-78页

作者： meng Ye Cai-Juan xia Bo-Qun zhang Yue Ma School of Science Xi'an Polytechnic University

Based on nonequilibrium Green's function method in combination with density functional theory, we study the electronic transport properties of dipyrimidinyl-diphenyl molecules embedded in a carbon atomic chain sandwiched between zigzag graphene nanoribbon and different edge geometries C_2N-h2D electrodes. Compared with the graphene electrodes, the C_2N-h2D electrode can cause rectifying and negative differential resistance *** C_2N-h2D with zigzag edges, a more remarkable negative differential resistance phenomenon appears, whereas armchair-edged C_2N-h2D can give rise to much better rectifying behavior. These results suggest that this system can be potentially useful for designs of logic and memory devices.

关键词： nonequilibrium system memory

A H_(2)O-in-zircon perspective on the heterogeneous water content of crust-derived magmas in southern Tibet

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Science China Earth Sciences 2021年第7期64卷 1184-1194页

作者： Juntong meng xiaoping xia Lin MA Ziqi JIANG Jian XU Zexian CUI Qing YANG Wanfeng zhang Le zhang State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China College of Earth and Planetary Science University of Chinese Academy of SciencesBeijing 100049China School of Earth Science Guilin University of TechnologyGuilin 541004China

Geophysical and geochemical evidence revealed that certain amounts of water are stored in the Earth’s interior,and its distribution exhibits temporal and spatial *** studies indicate that the H_(2)O-in-zircon has a potential to reveal magma water *** secondary ion mass spectrometry(SIMS),we analyzed the zircon water content and oxygen isotopes in granitoids(two-mica granite,quartz monzonite,diorite,and granodiorite)from southern *** results are used to explore the diversity of water content in crust-derived magmas,which is also supported by the LA-ICPMS zircon trace element *** are low zircon water contents for two partial melting products of the ancient crust(peak at 85 and300 ppm,respectively).Meanwhile,there are high H_(2)O-in-zircon peaks(435 and 475 ppm,respectively)for two partial melting products of the juvenile *** calculated radiation damage accumulation in these zircon grains is below 3×10^(15)αdecay events mg^(–1),suggesting that the zircon grains are well *** is no correlation between REE+Y and H+P,indicating that the mechanism of charge balance for water uptaking into zircon,in which the excess of REE+Y to P controls Hcontent,is not applicable to the studied *** degree of magma fractionation cannot account for the zircon water content variation,because there is no co-variation between zircon Hf and H_(2)O ***,the degree of partial melting was unlikely to be responsible for the H_(2)O-in-zircon *** interpret that the H_(2)O-in-zircon variation reflects the influence of melting mode(dehydration ***-fluxed)and water content in the crustal *** the Late Devonian,dehydration melting of the crustal rocks was facilitated at elevated temperatures,which produced magmas with the lowest water ***-fluxed melting of the ancient crust would produce relatively“drier”magma than water-fluxed melting of the juvenile crust.

关键词： H_2O-in-zircon SIMS dehydration melting water-fluxed melting magma water content

Highly safe and ionothermal synthesis of Ti3C2 MXene with expanded interlayer spacing for enhanced lithium storage

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Journal of Energy Chemistry 2020年第8期29卷 203-209,I0007页

作者： Junbiao Wu Yu Wang Yaopeng zhang Hao meng Yan Xu Yide Han Zhuopeng Wang Yanfeng Dong xia zhang Department of Chemistry College of SciencesNortheastern UniversityShenyang 110819LiaoningChina

MXene is a rising star of two-dimensional(2D)materials for energy relative applications,however,the traditional synthesis of MXene etched by hazard HF acid or LiF+HCl mixed solution is highly dangerous with the risk of splashing or pouring liquid *** this work,we developed a water-free ionothermal synthesis of 2D Ti3C2 MXene via etching pristine Ti3AlC2 MAX in low-cost choline chloride and oxalic acid based deep eutectic solvents(DES)with the presence of NH4F,thus it was highly safe and convenient to operate solid precursor and product materials at room *** from the low vapor pressure and solvating properties of DES,the prepared Ti3C2(denoted as DES-Ti3C2)possessed a high purity up to 98% compared with 95% for HF etched Ti3C2(denoted as HF-Ti3C2).Notably,an expanded interlayer spacing of 1.35 nm could be achieved due to the intercalation of choline cations in DES-Ti3C2,larger than that of HF-Ti3C2(0.98 nm).As a result,the DES-Ti3C2 anodes exhibited enhanced lithium storage performance,such as high reversible capacity of 208 m Ah g-1at 0.5 A g-1,and long cycle life over 400 times,outperforming most reported pure MXene *** ionothermal synthesis of MXene developed here may pave a new way to safely prepare other MXene for various energy relating applications.

关键词： Ionothermal synthesis Deep eutectic solvents MXene Expanded interlayer spacing Lithium ion batteries

Effect of a near-zero magnetic field on development and flight of oriental armyworm(Mythimna separata)

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Journal of Integrative Agriculture 2021年第5期20卷 1336-1345页

作者： AN meng-meng zhang Lei CHENG Yun-xia Thomas W.SAPPINGTON PAN Wei-dong JIANG Xing-fu State Key Laboratory for Biology of Plant Disease and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China Corn Insects and Crop Genetics Research Unit USDA-ARSAmesIA 50011USA Beijing Key Laboratory of Bioelectromagnetics Institute of Electrical EngineeringChinese Academy of SciencesBeijing 100190P.R.China

The geomagnetic field affects all living organisms on the *** this study we investigated the developmental and behavioral effects of rearing Mythimna separata in a near-zero magnetic field(<500 n T)compared to the local geomagnetic field(approximately 50μT).The near-zero magnetic field produced by a Helmholtz coil system significantly lengthened larval and pupal development durations,increased male longevity,and reduced pupal weight,female reproduction,and the relative expression level of the vitellogenin(Vg)gene in newly emerged ***,the near-zero magnetic field had a considerable negative effect on the mating ratio of *** *** addition,the moths in the near-zero magnetic field displayed less flight activity late in the night than those in the Earth's normal geomagnetic field,indicating that the flight rhythm of *** may be affected by the near-zero magnetic *** in magnetic field intensity may have negative effects on the development and flight of oriental armyworm,with consequent additional effects on its migration.

关键词： development flight activity geomagnetic field Mythimna separata near-zero magnetic field

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梯度醇沉盐藻多糖结构及免疫调节活性分析

食品与发酵工业 2025年第1期51卷 182-188页

作者：张喜峰张浩刘霞王兆丰罗光宏河西学院生命科学与工程学院甘肃张掖734000 甘肃省河西走廊特色资源利用重点实验室甘肃张掖734000 天水师范学院生物工程与技术学院甘肃天水741000 河西学院甘肃省微藻技术创新中心甘肃张掖734000

采用40%、60%和80%(体积分数)的乙醇分级沉淀法获得不同分子质量的盐藻多糖(polysaccharide ofDunaliella salina,PD),分别命名为PD-40、PD-60和PD-80,分析3种多糖组分的高效凝胶渗透色谱、傅里叶变换红外光谱(Fourier transform infrared spectrometer,FT-IR)、单糖组成、扫描电镜、热重分析(thermogravimetric analysis,TGA)、刚果红实验等理化性质,并在RAW 264.7细胞培养物中评估其体外免疫活性。结果表明,当乙醇体积分数分别增加至40%、60%和80%,依次产生3个分子质量下降的PD组分(PD-40>PD-60>PD-80)。基于FT-IR、TGA结果分析,不同分子质量的多糖在结构或热稳定性方面无差异。3个PD组分都由10个单糖残基组成,但摩尔比不同,其中,PD-40组分的含量最多且分子质量最大(M_(W)=2.31×10^(7)),占PD总质量的61.4%,具有最高的半乳糖摩尔比和糖醛酸含量;此外,PD-40组分能显著增强RAW 264.7细胞中NO和活性氧的产生以及吞噬活性。乙醇分级沉淀法是一种从盐藻中分离具有免疫活性多糖的有效方法,且可减少溶剂消耗。

关键词：分级沉淀盐藻免疫活性理化性质单糖组成

Chloroaluminate ionic liquid catalyzed isomerization of n-pentane in the presence of product distribution improver

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Petroleum Science 2011年第2期8卷 219-223页

作者： xia Rong＇an zhang Rui meng xianghai Liu Zhichang meng Jiaying Xu Chunming State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China

The ionic liquid Et3NHC1-2AIC13 can catalyze the isomerization of n-pentane. This paper investigates the ionic liquid catalyzed isomerization performance of n-pentane with several product distribution improvers in an autoclave. The product distribution of n-pentane isomerization could be improved by such improvers as benzene, cyelohexane, and methyl cyclohexane at the expense of conversion of n-pentane. The optimal product distribution improver was determined to be cyclohexane. The yield of isomerate and the selectivity of liquid isoalkanes increased, whereas the conversion of n-pentane decreased, with increasing cyclohexane amount. At the same conversion of n-pentane, the research octane number （RON） of liquid product, with cyclohexane amount of 0.5 wt%, was about 1.3 higher than that without cyclohexane. At the same reaction conditions, the presence of cyclohexane enhanced the yield of isomerate, the selectivity of liquid isoalkanes, and the RON of the liquid product, but reduced the conversion of n-pentane.

关键词： Isomerization ionic liquid improver pentane cyclohexane

Flex Ethernet Technology and Application in 5G Mobile Transport Network

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China Communications 2021年第2期18卷 250-258页

作者： meng zhang Research Institute of Telecommunications Transmission(RITT) China Academy of Information Communications Technology(CAICT)MIITBeijing 100191China

With the advent of 5G era,the rise of cloud services,virtual reality/virtual reality(AR/VR),vehicle networking and other technologies has put forward new requirements for the bandwidth and delay of the bearer *** Ethernet technology cannot meet the new requirements very *** Ethernet(FlexE)technology has emerged as the times *** paper introduces the background,standardization process,functional principle,application mode and technical advantages of FlexE technology,and finally analyses its application prospects and shortcomings in 5G mobile transport network.

关键词： Flex Ethernet(FlexE) 5G mobile transport network network slicing

Arsenic species analysis in porewaters and sediments using hydride generation atomic fluorescence spectrometry

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Journal of Environmental Sciences 2006年第5期18卷 995-999页

作者： LIAO meng-xia DENG Tian-long College of Materials Chemistry and Chemical Engineering Chengdu University of Technology Chengdu 610059 China Qinghai Institute of Salt Lakes Chinese Academy of Sciences Xining 810008 China

It was observed that the atomic fluorescence emission due to signal during the determination of As（Ⅲ） in the mixture of As（Ⅲ） and As（V） could has a 10% to 40% of fluorescence emission As（V）. Besides, interferes from heavy metals such as Pb（Ⅱ）, Cu（Ⅱ） can cause severe increase of the signals as compared to the insignificant effects caused by Cd（Ⅱ）, Zn（Ⅱ）, Mn（Ⅱ） and Fe（Ⅲ）. On the basis of further studies, the masking agent of 8-hydroxyquinoline was used as an efficient agent to eliminate interference of As（V） emission and the heavy metal of Cu^2＋ and Pb^2＋ in the measurements of arsenic species, After a series standard additions and CRM researches, a sensitive and interference-free analytical procedure was developed for the speciation of arsenic in samples of porewaters and sediments in Poyang Lake, China.

关键词： arsenic speciation 8-hydroxyquinoline porewaters sediments Poyang Lake

Electrochemical synthesis of functionalized gem-difluoroalkenes with diverse alkyl sources via a defluorinative alkylation process

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Organic Chemistry Frontiers 2022年第1期9卷 95-101页

作者： Haoxiang zhang mengze Liang xiao zhang meng-Ke He Chao Yang Lin Guo Wujiong xia State Key Lab of Urban Water Resource and Environment School of ScienceHarbin Institute of Technology(Shenzhen)Shenzhen518055China Wenzhou University WenzhouZhejiang 325000China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan 453007China

An electrochemical defluorinative alkylation protocol ofα-trifluoromethyl alkenes is *** reaction enables the preparation of functionalized gem-difluoroalkenes with the use of diverse alkyl sources including organohalides,N-hydroxyphthalimide(NHP)esters and Katritzky *** method exhibits lots of synthetic advantages including mild conditions,simple operation,and convenience of amplification,and provides a new route for the synthesis of gem-difluoroalkenes。

关键词： synthesis alkyl alkylation

Ionotropic receptor 8a is involved in the attraction of Helicoverpa armigera to acetic acid

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Insect Science 2022年第3期29卷 657-668页

作者： xia-Xuan zhang Bin Yang Dong-Dong Sun meng-Bo Guo Jie zhang Gui-Rong Wang State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina Lingnan Guangdong Laboratory of Modem Agriculture Genome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhenGuangdong ProvinceChina College of Life Sciences Anhui Normal UniversityWuhuAnhui ProvinceChina

Ionotropic receptors(IRs)were first found in Drosophila melanogaster,and derive from ionotropic glutamate receptors(iGluRs),which are implicated in detecting acids,ammonia,amine,temperature and *** IRs are involved in sensing acid odors in a few insects,such as ***,Aedes aegypti,and Manduca sexta,the function of IRs in Helicoverpa armigera is still ***8a was confirmed to be a co-receptor associated with acid *** the results of phylogenetic analysis,HarmIR8a displayed high similarity compared to homologs in ***,***,and ***,suggesting that HarmIR8a might have a consistent function as a co-receptor for acid *** this study,clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)-mediated genome editing was implemented to knockout HarmIR8a for in vivo functional *** and behavioral assays were performed to compare the differences between HarmIR8a knockout mutants and wild type *** electroantennogram(EAG)analysis,we found that wild type *** adults could detect short-chain carboxylic *** addition,wind tunnel experiments showed that 1%acetic acid attracted wild type *** ***,acid sensing and attraction were reduced or abolished in the HarmIR8a knockout *** data suggest that HarmIR8a is important for *** to detect short-chain carboxylic acids and mediate attraction behavior to acetic acid.

关键词： acetic acid CRISPR/Cas9 electroantennogram Helicoverpa armigera ionotropic receptors