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Real-time and in-situ intracellular ATP assay with polyimidazolium brush-modified nanopipette

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Science China Chemistry 2020年第7期63卷 1004-1011页

作者： Kailin zhang Tianyi Xiong fei wu Qingwei Yue Wenliang ji ping Yu Lanqun Mao Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living BiosystemsInstitute of Chemistrythe Chinese Academy of Sciences(CAS)Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The level and dynamics of adenosine 5’-triphosphate(ATP) in single living cells are closely related to many kinds of important physiological and pathological processes. Herein, we report a nanosensor based on polyimidazolium brush(PimB)-modified nanopipette for intracellular ATP assay, which shows good selectivity, high spatiotemporal resolution and excellent *** the specific supramolecular interaction between polyimidazolium and ATP, and the rationally tunable property of the ion transport at a confined nanopipette enable the selective assay of ATP even in complex intracellular environment. Moreover, the tiny tip(ca.300 nm) and the low polarized current(e.g., 1 nA) essentially make the as-prepared nanosensor safe to the living cells. The nanosensor is demonstrated to be useful for in-situ monitoring the basal ATP levels of chromaffin cells from wild-type mice and DJ-1 knockout mice, and for real-time monitoring the metabolism process of intracellular ATP.

关键词： intracellular ATP nanosensor ion transport single-cell analysis supramolecular interaction

Catalytic asymmetric dipolar cycloadditions of indolyl delocalized metal-allyl species for the enantioselective synthesis of cyclopenta[b]indoles and pyrrolo[1,2-α]indoles

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Science China Chemistry 2021年第1期64卷 34-40页

作者： fei Tian wu-Lin Yang Tao Ni jian zhang Wei-ping Deng Shanghai Key Laboratory of New Drug Design and School of Pharmacy East China University of Science and TechnologyShanghai 200237China

The development of novel synthons and efficient methods to synthesize chiral polycyclic indoles has been a hot topic in organic synthesis and medicinal chemistry owing to their broad applications in medicines,pesticides,and other functional ***,we disclosed novel indolyl substituted metal-allyl zwitterionic intermediates through the decarboxylation of conveniently available vinyl indoloxazolidones,which could be regarded as two types of dipolar species through the anionic *** palladium-π-allyl species tended to serve as an all-carbon 1,3-dipole in the asymmetric[3+2]cycloaddition with electrondeficient alkenes,which furnished polysubstituted cyclopenta[b]indoles with high regio-and ***,the iridium-π-allyl species was recognized as an aza-1,3-dipole in asymmetric[3+2]cycloaddition with in situ generated C1 ammonium enolates,affording pyrrolo[1,2-α]indoles with high diastereo-and *** addition,the dipolar cycloadditions could be easily scaled-up and several synthetic transformations of the cycloadducts were demonstrated for the rapid synthesis of diverse chiral polycyclic indoles.

关键词： palladium catalysis iridium catalysis asymmetric synthesis dipolar cycloaddition polycyclic indoles

Analysis of Non-WSSUS Fading Dispersive Channel Model

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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 20-25页

作者： zhang Ming zhang jian-hua jiANG Jun zhang ping wu Yu-fei Wireless Technology Innovation Labs (WTI) Beijing University of Posts and TelecommunieationsBeijing 100876 P.R. China Motorola (China)Electronics Ltd. No. 4 Avenue Technology Development Zone Tianjin 301800 P.R. China

The Wide-Sense Stationary Uncorrelated Scattering （WSSUS） model has long been viewed as a basic channel model to describe the fading dispersive channel. But non- WSSUS models have more universal applicability when the wireless mobile channel with broadband is studied with finer and more detailed knowledge of propagation environments. So the four-Dimension （4-D） characteristics of channel, namely time, lag, frequency, and Doppler, should be studied together. In this paper, Wigner-Ville distribution of Time-Frequency （TF） domain is introduced to analyze channel in which the incidence rays are non-stationary and correlated with each other. Several channel models, according to different move modes of incidence rays, with time-varying Doppler shift are designed and 4-D Local Scattering Function （LSF） are computed and simulated respectively. Our simulation results show the LSF present asymmetric and non-periodic TF distri- bution for some symmetric and periodic move modes of incidence rays.

关键词： non- WSSUS channel stimulation local scattering function Wigner- Ville distribution Doppler shift

A unified model for determining fracture strain of metal films on flexible substrates

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Journal of Materials Science & Technology 2020年第19期54卷 87-94页

作者： Xu-ping wu Xue-Mei Luo Hong-Lei Chen ji-Peng Zou Guang-ping zhang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of Chin1Shenyang 110016China

Failure strain determination of polymer-supported thin films is a key for the design of the flexible devices.A theoretical model R/R0=(L/L0)2(R,L are the electrical resistance and the length of the stretched film,respectively.R0,L0 are the corresponding initial values.)has been widely used to determine the fracture strain of thin films on flexible ***,this equation loses its function in some special ***,a simple and universal theoretical model was proposed to determine the fracture strain of metal thin films on flexible substrates in more generally *** this model,we investigated the thicknessdependent failure strains of Cu-5 at.%Al films with thickness of 10 nm,200 nm,1000 nm,and Ti films with thickness of 50 nm,100 nm,300 *** model was also employed to study the published data *** results showed that the new model provided a fairly good prediction of the failure strains of different films.

关键词： Thin films Fracture Electrical resistance Microstructure Flexible substrate

A novel phenylpropanoid glycoside from Callicarpa kwangtungensis Chun

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Chinese Chemical Letters 2009年第7期20卷 827-829页

作者： Er Lei Xie Guo ping Zhou Teng fei ji Jun wu Gui ping Yuan jiangxi Provical Institute for Drug and Food Control Nanchang 330029 China Key Laboratory of Bioactive substances and Resources Utilization of Chinese Herbal Medicine Institute of Materia MedicaChinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050 China Guangdong Key Laboratory of Marine Materia Medica South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

A novel phenylpropanoid glycoside, Callicarposide A has been isolated from the aerial parts of Callicarpa kwangtungensis Chun. The chemical structure is elucidated on the basis of spectral analysis. C 2009 Teng fei ji... 详细信息

关键词： Callicarpa kwangtungensis Chun Phenylpropanoid glycoside Callicarposide A

Genotypic and Environmental Variations of Arabinoxylan Content and Endoxylanase Activity in Barley Grains

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Journal of Integrative Agriculture 2013年第8期12卷 1489-1494页

作者： zhang Xiao-qin XUE Da-wei wu fei-bo zhang Guo-ping Agronomy Department Zhejiang University College of Life and Environmental Sciences Hangzhou Normal University

Arabinoxylan （AX） content in barley grains is an important quality determinant when barley is used as raw material of malt or beer production. The cultivar and environmental variations of total arabinoxylan （TAX）, water extractable arabinoxylan （WEAX） and endoxylanase activity （EA） were investigated using eight barley cultivars growing at seven locations with diverse environmental conditions. The results showed that both barley cultivar and location significantly affected the TAX, WEAX and EA levels, but the variations of TAX content and EA were mainly attributed to cultivar, while the impact of location on WEAX content was greater than that of cultivar. Correlation analysis indicated that TAX was significantly correlated to wuAX.

关键词： arabinoxylan barley (Hordeum vulgare L.) cultivar endoxylanase environment

Broadband channel measurement and analysis

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The Journal of China Universities of Posts and Telecommunications 2006年第3期13卷 24-28页

作者： zhang Ming zhang jian-hua jiANG Jun zhang ping wu Yu-fei Wireless Technology Innovation Labs (WTI) Beijing University of Posts and Telecommunications Beijing 100876 China

An outdoor propagation measurement campaign for beyond 3G （B3G） as well as a wide-band indoor measurement campaign have been performed recently in Beijing, China, in which the sounding signals are transmitted by an one-antenna base station and received by a two-antenna mobile receiver operated at 3.49～3.51 GHz bandwidth. Different scenarios： stationary line-of-sight （LoS）, stationary non-LoS （NLoS） scenarios, and dynamic NLoS are deliberately chosen in a classic urban environment and office environment. The initial results are presented in this article. Parameters including vector channel impulse response, path loss, rays number, excess delay spread etc. are extracted, analyzed, and briefly reported here.

关键词： Broadband measurement Beyond 3G path loss,multipath delay rays number

Genotypic differences in callus induction and plant regeneration from mature embryos of barley(Hordeum vulgare L.)

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第5期12卷 399-407页

作者： Yong HAN Xiao-li jiN fei-bo wu Guo-ping zhang Department of Agronomy College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China

An efficient induction system and regeneration protocol based on mature barley embryos were *** isolated from mature seeds,dehusked by hand and inoculated with longitudinally bisected sections,showed low contamination and high primary callus-forming *** influences of nine culture media on primary callus induction and germination from the mature embryos of barley cultivars Golden Promise and Zaoshu 3 were *** results showed that the two cultivars had much higher values of primary callus induction in the B16M6D medium as compared to the other eight medium formulations,with a frequency of 74.3% and 78.4% for Golden Promise and Zaoshu 3,***,Zaoshu 3 demonstrated particularly high stability in callus induction over the different media,indicating its potential utilization in callus induction and regeneration for its good agronomic traits and wide *** were significant differences amongst 11 barley genotypes in terms of primary callus induction in the optimum medium,with percentages of callus induction and germination response ranging from 17.9% to 78.4% and 2.8% to 47.4%,*** plantlets of Dong 17,Golden Promise,and Zaoshu 3 were successfully de-veloped from primary calli through embryogenesis,with green plant differentiation frequencies ranging from 9.7% to 21.0% across genotypes.

关键词： Barley Mature embryo Genotypic difference Primary callus Plant regeneration

Analytical modelling of the mechanical damage of soil induced by lightning strikes capturing electro-thermal,thermo-osmotic,and electro-osmotic effects

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Journal of Mountain Science 2022年第7期19卷 2027-2043页

作者： RAO ping-ping OUYANG Pei-hao NIMBALKAR Sanjay CHEN Qing-sheng wu Zhi-lin CUI ji-fei Department of Civil Engineering University of Shanghai for Science and TechnologyShanghai200093China School of Civil and Environmental Engineering University of Technology Sydney15 BroadwayUltimoNSW2007Australia Technology Research Center of Ecological Road Engineering Hubei University of TechnologyWuhan430068China

This article presents a mathematical model for simulating the mechanical behaviour of lightning strikes and analysing the resulting damage to the *** article focuses on the electro-thermal effect and seepage caused by lightning strikes in ***,a numerical model based on the conservation laws of momentum,mass and energy is developed for soil subjected to lightning *** to field observations and theoretical calculations are used to demonstrate the efficacy and accuracy of numerical *** findings demonstrate that lightning strikes can cause soils to experience both seepage force and heat *** the calculative condition of this article:by increasing the intrinsic permeability of the soil,k_(p)(≥10^(-10)m^(2)),the seepage force can be effectively reduced,hence reducing the risk of lightning strikes;improving the electrical conductivity of the soil β(≥10^(-1) S/m^(2))and lowering its thermal expansion coefficient(≤10^(-6)K^(-1))can greatly reduce the damage caused by lightning strikes to the *** preceding investigations demonstrate that the suggested model is capable of evaluating mechanical damage caused by lightning in the soil,and the findings contribute to a better understanding of soil mechanical response to lightning strikes.

关键词： Lightning strikes Analytical modelling Soil damage Electro-thermo-osmotic effect Conservation laws