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Identification of Secondary Metabolites in Tunisian Tilia platyphyllos *** MALDI-TOF and GC-MS

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Journal of Renewable Materials 2024年第4期12卷 827-842页

作者： Ayda Khadhri Mohamed Mendili Marwa Bannour-Scharinger Eric Masson Antonio Pizzi University of El-Manar II Faculty of SciencesPlantSoilEnvironment Interactions LaboratoryCampus AcademiaTunis2092Tunisia LERMAB University of Lorraine27 Rue Philippe SeguinEpinal88000France

This study is the first to evaluate the phytochemical content and biological properties of Tunisian *** Scop.A total of 23 compounds of essential oils were identified by gas chromatography-mass spectrometry(GC-MS)analysis of bracts and fruit *** results show that oxygenated monoterpenes were the dominant class of essential *** phenolic composition was investigated by matrix-assisted laser desorption/ionizationtime of flight(MALDI-TOF).The analysis showed that the chemical profiles of the ethanolic extracts of bracts and fruits are substantially *** highest polyphenol content was found in the ethanolic extracts of the fruits(7.65 mg gallic acid equivalents(GAE).g−1 on dry weight(DW).As for the antioxidant capacity,it was recorded in the essential oils of the fruits(IC_(50)=0.91 ***^(−1)).The results obtained showed that the antioxidant activity of the fruit essential oil was higher than that of the ethanol *** fruit essential oil was also found to have the highest reducing power(IC_(50)=0.67 ***^(−1)).In terms of iron-chelating power,fruit essential oil has the highest chelating power(IC_(50)=2.03 ***^(−1)).Compared to the ethanolic extract,the essential oil had the maximum antioxidant *** enzymatic activity of acetylcholinesterase(AChE)inhibition of the essential oil from *** bracts had the most potent inhibitory effect(IC_(50)=0.77 ***^(−1)),followed by the essential oil from the fruits(IC_(50)=0.95 ***^(−1)).The results suggest that *** can be used as a potential source of naturally occurring bioactive compounds and antioxidants.

关键词： T.platyphyllos antioxidant activity acetylcholinesterase inhibition essential oil MALDI-TOF GC-MS

AN APPROACH TO THE SUPERGRAVITY THEORIES

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Acta Mathematica Scientia 1983年第3期3卷 249-262页

作者：邵常贵 Wuhan Institute of Technology Wuhan Institute of mathematical Sciences academia siaica

In this paper we have established the ISO (3, 1|N),OSp(N|4) and S∪(2,2|N)supergravities, attempted a possible quantization and renormalization scheme of the ISO(3,1|N) supergravity. The embeddingof S∪(5) grand unified theory in the S∪(2,2|N)superunified theory is given and the method of particle multiplets in the supergravities is discussed.

关键词：一夕 AN APPROACH TO THE SUPERGRAVITY THEORIES

Optimizing piezoelectric performance of complex perovskite through increasing diversity of B-site cations

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Journal of Materials Science & Technology 2024年第3期170卷 78-86页

作者： Mengdi Cheng Dongyan Zhang Yangxi Yan Zhimin Li Pangpang Wang Ri-ichi Murakami School of Advanced Materials and Nanotechnology Xidian UniversityXi’an 710126China Nanomaterials Group Institute of SystemInformation Technologies and Nanotechnologies(ISIT)Fukuoka Industry-Academia Symphonicity(FiaS)4-1 KyudaishinmachiNishi-kuFukuoka 819-0388Japan School of Mechanical Engineering Chengdu UniversityChengdu 610106China

Piezoelectric materials with unique properties are hugely appealing for high sensitivity sensors and ultrasonic ***,Pb(Ni_(1/3)Nb_(2/3))O_(3)-Pb(Yb_(1/2)Nb_(1/2))O_(3)-PbTiO_(3)piezoelectric system was designed and investigated in *** optimized piezoelectric response(d_(33)=826 pC/N,d_(33)∗=1017 pm/V)together with good temperature stability and negligible performance degradation up to 10^(6) cycles was achieved in 0.58PNN-0.10PYN-0.32PT *** analysis revealed the amplification of intrinsic and extrinsic contributions in MPB region due to more spontaneous polarization orientations and an increase in chemical disorder of system after the introduction of *** origin of high piezoelectric response was investigated through the combination of scanning electron microscopy and piezoresponse force *** diversity of B-site cations was shown to enhance local structural heterogeneity,weaken long-range ferroelectric ordered domains,and lower free energy barrier via the formation of nanodomain configuration that promoted polarization rotation,thereby improving piezoelectric properties of the ***,it is suggested that increasing the diversity of B-site cations is an effective strategy for achieving outstanding piezoelectric performance.

关键词： PNN-PYN-PT ceramics Piezoelectricity enhancement Relaxation behavior Domain structure

Zn Dissolution-Passivation Behavior with ZnO Formation via In Situ Characterizations

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Energy & Environmental Materials 2024年第1期7卷 193-200页

作者： Tanyanyu Wang Masahiro Kunimoto Masahiro Yanagisawa Masayuki Morita Takeshi Abe Takayuki Homma Graduate School of Advanced Science and Engineering Waseda University1-104 TotsukamachiShinjuku-kuTokyo 169-8050Japan Office of Society-academia Collaboration for Innovation Kyoto UniversityGokashoUji 611-0011Japan Graduate School of Engineering Kyoto UniversityKyoto daigaku-katsuraNishikyo-kuKyoto 615-8510Japan

In this study,ZnO formation during the dissolution-passivation process of Zn anodes is observed via in situ Raman and optical *** Zn passivation during galvanostatic anodization merely follows the dissolution-precipitation model,whereas that of potentiodynamic polarization exhibits different behaviors in different potential ***,the Zn electrode is gradually covered by a ZnO precipitation film and then undergoes solid-state oxidation at~255 *** starting point of solid-state oxidation is well indicated by the abrupt current drop and yellow coloration of the electrode *** the pseudo passivation,an intense current oscillation is ***,blink-like color changes between yellow and dark blue are revealed for the first time,implying that the oscillation is caused by the dynamic adsorption and desorption of OH *** as-formed ZnOs then experience a dissolution-reformation evolution,during which the crystallinity of the primary ZnO film is improved but the solid-state-formed ZnO layer becomes rich in oxygen ***,oxide densification is realized,contributing to the Zn *** study provides new insights into the Zn dissolution-passivation behavior,which is critical for the future optimization of Zn batteries.

关键词： in situ characterization Zn dissolution and passivation ZnO formation

p-wave resonances in the exponential cosine screened Coulomb potential

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Communications in Theoretical Physics 2024年第7期76卷 105-113页

作者： Yuan-Cheng Wang Li Guang Jiao Aihua Liu Yew Kam Ho Stephan Fritzsche College of Physical Science and Technology Shenyang Normal UniversityShenyang 110034China College of Physics Jilin UniversityChangchun 130012China Helmholtz-Institut Jena D-07743 JenaGermany GSI Helmholtzzentrum fur Schwerionenforschung GmbH D-64291 DarmstadtGermany Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China Institute of Atomic and Molecular Sciences Academia SinicaTaipei 10617TaiwanChina

We perform benchmark calculations of the p-wave resonances in the exponentially cosine screened Coulomb potential using the uniform complex-scaling generalized pseudo-spectral *** present results show significant improvement in calculation accuracy compared to previous predictions and correct the misidentification of resonance electron configuration in previous *** is found that the resonance states approximately follow an n^(2)-scaling law which is similar to the bound *** birth of a new resonance would distort the trajectory of an adjacent higher-lying resonance.

关键词： complex-scaling method shape resonance generalized pseudospectral method exponential cosine screened Coulomb potential

EXCEPTIONALLY HIGH AND DIVERSE MUTATION RATES IN INSECTS SMALL rRNA

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Science China Chemistry 1985年第10期28卷 1060-1063页

作者：冯亚雄 KRUPP GUIDO GROSS J.HANS academia siaica Institut für Biochemie der Universitt Würzburg Shanghai Institute of Biochemistry D-8700 Würzburg FRG Rontgenring 11

The nucleotide sequence of 5S rRNA from the posterior silk gland of the silk worm Philosamia cynthia ricini has been determined. The comparison with other insect 5S rRNAs revealed an exceptionally conserved secondary structure, in spite of an extremely high mutation rate: Thirteen nucleotides are different in Philosamia and Drosophila 5S rRNA, but all substitutions are either compensatory or occur in loops or introduce G:U base pairs. The rates of base substitution per site per year of several insect species (diptera and lepidoptera) 5S and 5.8S rRNAs are compared with those occurring in vertebrate rRNAs. In the latter cases the rates are remarkably constant, whereas their value is not only about twofold higher in insect rRNAs, but is found to be extremely large in the 5S rRNA of the silkworm Bombyx mori. These data demonstrate that phylogcnetic conclusions derived from small rRNA sequence comparisons are only of limited value.

关键词： EXCEPTIONALLY HIGH AND DIVERSE MUTATION RATES IN INSECTS SMALL rRNA rate

THIRD ORDER NONLINEAR OPTICAL PROPERTIES OF PERNIGRANILINE SOLUTION IN CONCENTRATED SULFURIC ACID

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Chinese Journal of Polymer Science 1996年第1期14卷 80-85页

作者：万梅香李明米辛姜谦叶佩弦 Institute of Chemistry Academia Sinica Beijing 100080 Institute of Physics Academia Sinica Beijing 100080

The fully oxidized state of polyaniline (PANI), pernigraniline (PN), was synthesized by oxidation of the emeraldine base form of PAM dissolved in NMP solvent with m-chloroperoxybenzoic acid. The resulted PN was characterized by FTIR and UV-Visible spectra. The third-order nonlinear optical properties of PN in concentrated sulfuric acid (PN/H2SO4) were measured by a degenerated four wave mixing (DFWM) method. The results obtained suggest that the soliton-pair intermediate state associated with the degenerated state does not play a major role in the third order nonlinear optical properties of PANI.

关键词： polyaniline pernigraniline degenerated four waves mixing (DFWM) third-order nonlinear optical properties

ELECTROCHEMICAL STUDIES ON CONDUCTING COMPOSITE FILMS FROM POLYURETHANE AND POLYPYRROLE

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Chinese Journal of Polymer Science 1988年第4期6卷 377-385页

作者：毕先同裴啟兵李永舫 Institute of Chemistry academia Sinica academia Sinica Beijing

A study on the electrooxidative polymerization of pyrrole onto polyurethane-coated platinum electrodes and the electrochemical properties of the composite polyurethane/polypyrrole films （PU/PPy） as-prepared is presented. It is found that polypyrrole grows layer by layer from the polyurethane/platinum interface through the polyurethane matrix, and ca. 20 wt.% of polypyrrole will fill up the matrix. Cyclic voltemmograms show that the composite films are porous, and the reduction-reoxidation （redox） rate of the composite films is limited by the diffusion of counteranions through the films. Larger anion size leads to slower diffusion process. The composite films can also act as modified electrodes.

关键词： Polypyrrole, Conducting composite Electrochemistry

Instantaneous Temperature-rise History and Nonequilibrium Thermophysical Properties of Thin Films Irradiated by Transient Laser Pulse

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Science China Mathematics 1993年第1期36卷 109-116页

作者：唐大伟曹卉周本濂何冠虎张才根 Institute of Metal Research academia Sinica International Center for Materials Physics Academia Sinica Shanghai Institute of Technical Physics Academia Sinica

Recent development in the study of nonequilibrium thermophysical properties of thin films in our lab is reported. A high-speed indirect heating system by using 0.1 μs CO_2 laser pulse was established. A photoelectric installation for micrometric length-change measurement, an infrared radiation pyrometer for transient temperature measurement, a high-speed acquisition system as recording device and microcomputer system for data treatmeat were developed. Using the systems, the traditional flash method is extended to the measurement of thermal diffusivity of the thin films of around 50 μm in thickness, and deviations of this method is analyzed for the case of thin film specimens. Nonsynchronous change of temperature rise and thermal expansion under transient heating was observed.

关键词： instantaneous temperature-rise history thin films nonequilibrium thermophysical properties transient laser pulse.