检索结果-南通市图书馆

Highly efficient capture of thorium ion by citric acid-modified chitosan gels from aqueous solution

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第5期35卷 361-365页

作者： Linshan peng Qihang peng Tianxiang jin Zhirong Liu yong Qian State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices East China University of TechnologyNanchang 330013China

A novel citric acid-modified chitosan gel(CSCA)was synthesized through a simple one-step process and was used to extract thorium ions from *** CSCA samples with varying chemical compositions were analyzed using SEM with mapping EDS,FT-IR,and static water contact angle measurements,and their adsorption behaviors were studied in *** results showed that the adsorption performance of CSCA improves with the increase of CA content in the *** possesses an impressive capacity for thorium adsorption of 279.8 mg/***,it showed an ultra-fast adsorption rate and reached equilibrium within 30 *** terms of recyclability,the CSCA still retained more than 86%of its initial adsorption capacity after 6 cycles of *** functional theory(DFT)analysis reveals that the good selectivity of this material towards thorium ions should be attributed to the high density of adsorption sites and strong interaction between carboxyl groups and thorium *** work could be beneficial in the design and synthesis of new polymer materials for extracting thorium.

关键词： Thorium Adsorption Citric acid Chitosan DFT calculation

Two New Dihydroflavanoids from Patrinia vittosa Juss (II)

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2006年第4期17卷 485-488页

作者： jin yong peng Guo Rong FAN Yu Tian WU Shanghai Key Laboratory for Pharmaceutical Metabolite Research School of Pharmacy Second Military Medical University Shanghai 200433

Two new dihydroflavonoids named villosin A and viUosin B were obtained from the traditional Chinese medicinal herb Patrinia viUosa Juss. Their structures were elucidated as （2S）-5, 2＇, 6＇-trihydroxy-2＂, 2＂-dimethylpyrano [5＂, 6＂： 6, 7]flavanone 1 and （2S, 3＂S）-5, 2＇, 6＇- trihydroxy-3＂-γ, γ-dimethylallyl-2＂, 2＂-dimethyl-3＂, 4＂-dihydropyrano [5＂, 6＂： 6, 7] flavanone 2 by spectroscopic methods including UV, IR, HR-TOF- MS, 1D NMR and 2D NMR techniques.

关键词： Patrinia villosa Juss dihydroflavonoids.

Secure symbol level precoding for cell-free network based on band-region constraint of the eavesdropper’s receiving signal

在线全文

学校读者我要写书评

暂无评论

High Technology Letters 2024年第3期30卷 304-309页

作者： LI Zewen jin yong FU Chunling peng Xin HU Zhentao School of Artifical Intelligence Henan UniversityZhengzhou 450000P.R.China School of Physics and Electronics Henan UniversityKaifeng 475000P.R.China

A symbol level secure precoding scheme based on band-region constraint of the eavesdropper’s receiving signal is proposed to enhance the energy efficiency of cell-free multiple-input multiple-output(MIMO)networks in the presence of an eavesdropper while guaranteeing the quality of service(QoS)of user and the security of ***,to lighten its high computational complexity,original problem is divided into several cascade sub-problems firstly,and then those sub-problems are handled by combining Lagrangian dual function and improved Hooke-Jeeves method *** ex-periment with other secure symbol-level precoding schemes demonstrate that proposed scheme can achieve the lower power consumption with almost same symbol error rate and QoS of user.

关键词： cell-free symbol-level precoding(SLP) physical layer security(PLS) multi-ple-input multiple-output(MIMO) band-region constraint

A new bioactive prenylated dihydroflavanoid from Dolichos tenuicaulis (Baker) Craib

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2007年第3期18卷 293-296页

作者： jin yong peng Hal Yan Liu Yan Qi Xu Han You Wei Xu Li Na Xu Qi Wei Xu School of Pharmacy Dalian Medical University Dalian 116027 China People＇s Hospital of the State of Xishuangbanna Yunnan 666100 China

A new prenylated dihydroflavonoid was obtained from the root of Dolichos tenuicaulis （Baker） Craib. The structure was elucidated as （2S）-5,2＇,6＇-trihydroxy-3＇″, 8-di （γ,γ-dimethyl-allyl）-2＇″, 2＇″-dimethylpyrano-[5＇″,6＇″： 6,7]-2＇″″,4＇″″-cyclohexadiene-1 ＇″″-one-[2＇″″,3＇″″： 3＇,4＇]-flavanone, named dolichnin A, by spectroscopic methods including UV, IR, HR-EI-MS, 1D NMR and 2D NMR techniques, and subsequently, the anticancer activity of this compound to inhibit human cancer cells＇ growth including A549, BEL-7402, Hep-3B, SMMC7721, HT-29, MCF-7, SGC-7902, K562, A498 and PC3 cell lines by MTT method was evaluated in vitro.

关键词： Dolichos tenuicaulis (Baker) Craib Prenylated dihydroflavonoid Anticancer activity

Mechanisms involved in the cytotoxic effects of berberine on human colon cancer HCT-8 cells

在线全文

学校读者我要写书评

暂无评论

BIOCELL 2012年第3期36卷 113-120页

作者： LI-NA XU BI-NAN LU MING-MING HU YOU-WEI XU XU HAN YAN QI jin-yong peng College of Pharmacy Dalian Medical University9 Western Lvshun South RoadDalian 116044China Institute of Chinese Minority Traditional Medicine Minzu University of China27 Zhongguancun South AvenueHadian districtBeijing 100081China Research Institute of Integrated Traditional and Western Medicine of Dalian Medical University Dalian 116011China

Berberine,a constituent of some traditional Chinese medicinal plants,has been reported to have cytotoxicity effects on different human cancer cell *** is no available information about the effects and mechanism of action of berberine on human colon cancer cell line *** this paper,the cytotoxicity of berberine on HCT-8 cancer cells was investigated by MTT assay,fluorescence microscopy and flow cytometry *** data revealed that berberine could significantly inhibit the growth of HCT-8 cells in a dose-and time-dependent *** of apoptotic cells was studied with acridine orange/ethidium bromide *** concentrations of lactate dehydrogenase and both acid and alkaline phos-phatases were significantly increased in cell supernatants after berberine treatment,suggesting cell ***,flow cytometry analysis showed that berberine could arrest HCT-8 cells at S phase in a time-dependent *** further investigate the apoptotic molecular mechanism,reverse transcription-poly-merase chain reaction(RT-PCR)and western blotting methods were *** up-regulated mRNA and/or protein expressions of Fas,FasL,TNF-α,caspase-3 and down-regulation of pro-caspase-3 suggest that the death receptor pathway may be involved in the apoptotic pathway induced by *** of Bcl-2 and increase of Bax in mRNA and/or protein expressions showed that the Bcl-2 family proteins were involved in berberine-induced *** also found that berberine-induced apoptosis was associated with an up-regulated expressions of p53 and prohibitin(PHB),and decreased vimentin *** results suggest that berberine can suppress cell growth and reduce cell survival by arresting the cell-cycle and by inducing apoptosis of HCT-8 cells.

关键词： apoptosis cell cycle arrest death receptor pathway mitochondrial pathway natural product

Interface Design Strategy for GNS/AZ91 Composites with Semi-Coherent Structure

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 467-483页

作者： jing-peng Xiong Yi-Qi Zeng jin-Long Liu Wei-Cheng Wang Lan Luo yong Liu Key Laboratory of Lightweight and High Strength Structural Materials of Jiangxi Province School of Advanced ManufacturingNanchang UniversityNanchang 330031China School of Physics and Materials Science Nanchang UniversityNanchang 330031China

The interfacial structure plays an important role in the mechanical properties of magnesium matrix composite(MMCs)reinforced with graphene nanosheet(GNS)due to their poor wettability with the Mg *** interface design strategy was proposed to form the semi-coherent interfacial structure with superior bonding *** lattice mismatch and interfacial bonding strength between Mg/rare earth oxide/carbon were utilized as key characteristics to evaluate the interfacial *** oxide(La2O3)was selected as the intermediate candidate due to its low lattice mismatch and high interfacial bonding *** identify the interfacial structure of Mg/La2O3/graphene,first-principles calculations were conducted to calculate the ideal work of separation and electronic structure of the *** demonstrated the presence of strong ionic and covalent interactions at the interface,which theoretically verified the strong interfacial bonding strength among Mg/La2O3/graphene *** experimentally validate the interface strength,MMCs with the interface structure of Mg/La2O3/GNS were *** formation of in-situ La2O3 led to the successful attainment of semi-coherent structures between Mg/La2O3 and La2O3/GNS,resulting in high strength and good ductility of the ***,this work proposes a new approach to interface design in MMCs with an enhancement of mechanical properties.

关键词： Interface design strategy Magnesium matrix composite Graphene nanosheets Semi-coherent interface Mechanical properties

Probing the Two-stage Transition upon Crossing the Glass Transition of Polystyrene by Solid-state NMR

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2016年第4期34卷 446-456页

作者： yong-jin peng Chen-ting Cai Rong-chun Zhang Tie-hong Chen 孙平川李宝会 Xiao-liang Wang Gi Xue An-Chang Shi School of Physics Nankai University Tianjin 300071 China Key Laboratory of Functional Polymer Materials of Ministry of Education and College of Chemistry Nankai University and Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300071 China Department of Polymer Science and Engineering The School of Chemistry and Chemical Engineering State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210093 China Department of Physics and Astronomy McMaster University Hamilton Ontario L8S 4M1 Canada

A two-stage transition upon crossing the glass transition of polystyrene with increasing temperature was precisely determined and interpreted by using solid-state nuclear magnetic resonance （SSNMR）, 1H-XH dipolar couplings based double quantum-filtered （DQF） and dipolar filter （DF） experiments and 13C chemical shift anisotropy （CSA） based centerband-only detection of exchange （CODEX） experiment are used to fully characterize the time scale of molecular motions during the glass transition. While differential scanning calorimetry （DSC） and CODEX experiment predicted the first stage of glass transiton, DQF and DF experiments provided the evidence for the second stage transition during which the time scale of molecular motions changed from very slow （t 〉 ms） to very fast （t 〈 Its）. The first stage of glass transition begins with the occurrence of remarkable slow re-orientation motions of the polymer backbone segments and ends when the degree of slow motion reaches maximum. The onset and endpoint of the conventional calorimetric glass transition of polystyrene can be quantitatively determined at the molecular level by SSNMR. In the second stage, a subsequent dramatic transition associated with the melting of the glassy components was observed. In this stage liquid-like NMR signals appeared and rapidly increased in intensity after a characteristic temperature Tf （-1.1Tg）. The signals associated with the glassy components completely disappeared at another characteristic temperature Tc （-1.2Tg）.

关键词： Glass transition Polystyrene Heterogeneous dynamics Solid-state NMR.

Long-time Asymptotics for the Reverse Space-time Nonlocal Hirota Equation with Decaying Initial Value Problem:without Solitons

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2024年第3期40卷 708-727页

作者： Wei-qi peng yong CHEN School of Mathematical Sciences East China Normal UniversityShanghai 200241China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

In this work,we mainly consider the Cauchy problem for the reverse space-time nonlocal Hirota equation with the initial data rapidly decaying in the solitonless *** from the Lax pair,we first construct the basis Riemann-Hilbert problem for the reverse space-time nonlocal Hirota ***,using the approach of Deift-Zhou nonlinear steepest descent,the explicit long-time asymptotics for the reverse space-time nonlocal Hirota is *** the reverse space-time nonlocal Hirota equation,since the symmetries of its scattering matrix are different with the local Hirota equation,the v(λ_(i))(i=0,1)would like to be imaginary,which results in theδ_(λi)^(0)contains an increasing t(±Imv(λ_(i)))/2,and then the asymptotic behavior for nonlocal Hirota equation becomes differently.

关键词： Riemann-Hilbert problem reverse space-time nonlocal Hirota equation long-time asymptotics nonlinear steepest descent method

Simple preparation of C(CS)/g-C_(3)N_(4)/Co carbon aerogel and its catalytic performance for ammonium perchlorate

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第3期33卷 186-196页

作者： Yujie Yan Bo jin Rufang peng State Key Laboratory of Environment-friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang621010China

Biomass chitosan(CS)was used as a template,graphitic phase carbon nitride(g-C_(3)N_(4))with high nitrogen content and certain catalytic activity was used as a dopant,and nano-transition metal cobalt(Co)was used as a catalytic center *** carbon aerogel(C(CS)/g-C_(3)N_(4)/Co)with a three-dimensional network-like structure was prepared by assembling the three materials through experimental operations such as freeze-drying and high-temperature *** was demonstrated by scanning and transmission characterization that the CS in the carbon aerogel could provide more active sites for the cobalt nanoparticles,and the doping of graphite-phase carbon nitride as a template dispersed the cobalt nanoparticles and changed the conductivity of the *** investigate the catalytic effect of carbon aerogel on ammonium perchlorate(AP),it was investigated by differential thermal analyzer and TG thermal *** carbon aerogel was very effective in catalyzing AP,and the 10 wt% content of the catalyst reduced the AP pyrolysis peak from 703.9 to 595.5 *** to further investigate the synergistic effect of the three materials,further carbon aerogels such as C(CS)/Co,g-C_(3)N_(4)/Co were prepared and applied to catalyze AP,and the same ratio reduced the AP pyrolysis peak by 98.1℃ and 97.7℃.This result indicates a synergistic effect of the assembly of the three materials.

关键词： g-C_(3)N_(4) Chitosan Co Ammonium perchlorate Pyrolysis kinetics