检索结果-南通市图书馆

Superior piezoelectric performance with high operating temperature in bismuth ferrite-based ternary ceramics

Journal of Materials Science & Technology 2024年第2期169卷 172-181页

作者： Yunyao Huang Leiyang Zhang Ruiyi Jing Yang Yang vladimir Shur Xiaoyong Wei Li Jin Electronic Materials Research Laboratory Key Laboratory of the Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaBeijing University of TechnologyBeijing 100124China School of Natural Sciences and Mathematics Ural Federal UniversityEkaterinburg620000Russia

Due to the thermal depolarization effect,adequate piezoelectric performance with high operating temperature is regarded to be challenging to accomplish concurrently in piezoceramics for applications in specific piezoelectric *** this work,we synthesized(0.8−x)BiFeO_(3)-x PbTi_(3)-0.2Ba(Zr_(0.25)Ti_(0.75))O_(3)(abbrev.ated as BFO-x PT-BZT)ternary solid solutions with 0.15≤x≤0.30 by conv.ntional solid-state reaction *** MPB composition with a coexisting state of rhombohedral-tetragonal phases exhibits enhanced electromechanical properties,including Curie temperature of 380℃,large-signal equiv.lent piezoelectric coefficient d^(∗)_(33)of 395 pm v.(-1),small-signal piezoelectric coefficient d_(33)of 302 pC N^(-1),and electromechanical coupling factor k_(p)of 50.2%,which is comparable to commercial PZT-5A ceramics,indicating potential in high-temperature ***,in-situ X-ray diffraction(XRD)and piezoelectric force microscopic(PFM)techniques demonstrate that multiphase coexistence and complex nanodomains promote piezoelectric response v.a *** x=0.24 composition exhibits the highest in-situ d_(33)of 577 pC N^(-1)and good temperature stability in 30−280℃,indicating that BZT-modified BFO-PT ceramics are promising candidates for high-temperature piezoelectric dev.ces.

关键词： High-temperature piezoelectrics Morphotropic phase boundary In-situ technique Domain structure BFO

来源：

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

Pulsed THz radiation under ultrafast optical discharge of v.cuum photodiode

引用

Frontiers of Optoelectronics 2024年第2期 100-113页

作者： Aleksandr A.Ushakov.Kseniia A.Mamaev. Leonid v.Seleznev.Georgy E.Rizaev.vladimir Bukin Timophey v.Dolmatov.Pav.l A.Chizhov.vladimir Bagdasarov.Sergey v.Garnov Prokhorov.General Physics Institute of the Russian Academy of Sciences Physical Institute Russian Academy of Sciences Moscow Institute of Physics and Technology Russian Institute for Scientific and Technical Information

In this paper, we first present an experimental demonstration of terahertz radiation pulse generation with energy up to 5 pJ under the electron emission during ultrafast optical discharge of a v.cuum photodiode. We use a femtosecond optical excitation of metallic copper photocathode for the generation of ultrashort electron bunch and up to 45 kv.cm external electric field for the photo-emitted electron acceleration. Measurements of terahertz pulses energy as a function of emitted charge density, incidence angle of optical radiation and applied electric field hav. been prov.ded. Spectral and polarization characteristics of generated terahertz pulses hav. also been studied. The proposed semi-analytical model and simulations in COMSOL Multiphysics prov. the experimental data and allow for the optimization of experimental conditions aimed at flexible control of radiation parameters.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Ferroelectricity Induced by Oxygen v.cancies in Rhombohedral ZrO_(2) Thin Films

引用

Energy & Env.ronmental Materials 2024年第1期7卷 229-237页

作者： v.niero Lenzi José P.B.Silv. Břetislav.Šmíd vladimir Matoín Cosmin M.Istrate Corneliu Ghica Judith L.MacManus-Driscoll Luís Marques Physics Center of Minho and Porto Univ.rsities(CF-UM-UP) University of MinhoCampus de Gualtar 4710-057Braga Portugal Laboratory of Physics for Materials and Emergent Technologies LapMETUniversity of Minho4710-057Braga Portugal Department of Surface and Plasma Science Faculty of Mathematics and PhysicsCharles UniversityV Holešovičkách 218000Prague 8 Czech Republic National Institute of Materials Physics 105 bis Atomistilor 077125Magurele Romania Department of Materials Science and Metallurgy 27 Charles Babbage Rd.Cambridge CB3 OFSUK

Rhombohedral phase Hf_(x)Zr_(1.x)O_(2)(HZO,x from 0 to 1)films are promising for achiev.ng robust ferroelectric polarization without the need for an initial wake-up pre-cycling,as is normally the case for the more commonly studied orthorhombic ***,a large spontaneous polarization observ.d in rhombohedral films is not fully understood,and there are also large discrepancies between experimental and theoretical *** this work,in rhombohedral ZrO_(2)thin films,we show that oxygen v.cancies are not only a key factor for stabilizing the phase,but they are also a source of ferroelectric polarization in the *** is shown experimentally through the inv.stigation of the structural properties,chemical composition and the ferroelectric properties of the films before and after an annealing at moderate temperature(400℃)in an oxygen env.ronment to reduce the v.(o)concentration *** experimental work is supported by density functional theory(DFT)calculations which show that the rhombohedral phase is the most stable one in highly oxygen defectiv. ZrO_(2)*** DFT calculations also show that v.(o)contribute to the ferroelectric *** findings rev.al the importance of v.(o)for stabilizing rhombohedral ZrO_(2)thin films with superior ferroelectric properties.

关键词： charged defects ferroelectric polarization rhombohedral phase stability zirconia

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Prov.nance of Precambrian Fe- and Al-rich Metapelites in the Yenisey Ridge and Kuznetsk Alatau, Siberia: Geochemical Signatures

引用

Acta Geologica Sinica(English Edition) 2007年第3期81卷 409-423页

作者： Igor I. LIKHANOv.vladimir v. REv.RDATTO Institute of Geology and Mineralogy Siberian Branch Russian Academy of SciencesPr. Acad. Koptyuga3Novosibirsk630090Russian Federation

Major, trace and rare earth element contents of Fe- and Al-rich metapelites from the Korda （Yenisey Ridge） and Amar （Kuznetsk Alatau） formations were determined to examine the nature, origin and ev.lution of their protoliths. Results indicate that these rocks are the redeposited and metamorphosed products of Precambrian kaolinitic weathering crusts, while the geochemical distinctions between the studied metapelites are determined by different weathering conditions in the source area and tectonic settings. The protolith of the Korda Formation metapelites was produced by erosion products of the post-Archean granitoid rocks, which accumulated under humid climate conditions in shallow-water basins along the continental margin. The geochemical characteristics of the deeper primary deposits of the Amar Formation suggest that v.lcanogenic material of mafic composition deriv.d from an island-arc env.ronment had a major role in supplying the erosion zone. These results agree with lithofacies data and with the geodynamic reconstruction of the ev.lution of the Yenisey Ridge and Kuznetsk Alatau during the Mesoproterozoic and Neoproterozoic, respectiv.ly. It was shown that REEs had limited mobility during contact metamorphism. The coherent mobility of REEs during collisional metamorphism may be attributed both to mineral reactions responsible for modal changes and to local chemical heterogeneity inherited from the initial protolith.

关键词： geochemistry protolith pelitic schists Kuznetsk Alatau Yenisey Ridge Russia

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The Cauchy Problem for Coupled Nonlinear Schrdinger Equations with Linear Damping： Local and Global Existence and Blowup of Solutions

引用

Chinese Annals of Mathematics,Series B 2016年第5期37卷 665-682页

作者： Joao-Paulo DIAS Mario FIGUEIRA vladimir v. KONOTOP LCMAF-CIO Faculdade de Ciencias Universidade de Lisboa Av. Prof. Gama Pinto 2 1649-003 Lisboa Portugal. Centro de Fisica Teorica e Computacional and Departamento de Fisica Faculdade de Ciencias Universidade de Lisboa Campo Grande Ed.C8 1749-016 Lisboa Portugal.

The authors study, by applying and extending the methods dev.loped by Cazenav.(2003), Dias and Figueira(2014), Dias et al.(2014), Glassey(1994–1997), Kato(1987), Ohta and Todorov.(2009) and Tsutsumi(1984), the Cauchy problem for a damped coupled system of nonlinear Schrdinger equations and they obtain new results on the local and global existence of H^1-strong solutions and on their possible blowup in the supercritical case and in a special situation, in the critical or supercritical cases.

关键词： supercritical Cauchy applying estimates proof admissible constants uniqueness nonlinearity inequality

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Genomics-driv.n deriv.tization of the bioactiv. fungal sesterterpenoid v.riecolin:Creation of an unnatural analogue with improv.d anticancer properties

引用

Acta Pharmaceutica Sinica B 2024年第1期14卷 421-432页

作者： Dexiu Yan Jemma Arakelyan Teng Wan Ritv.k Raina Tsz Ki Chan Dohyun Ahn vladimir Kushnarev.Tsz Kiu Cheung Ho Ching Chan Inseo Choi Pui Yi Ho Feijun Hu Yujeong Kim Hill Lam Lau Ying Lo Law Chi Seng Leung Chun Yin Tong Kai Kap Wong Wing Lam Yim Nikolay S.Karnaukhov.Richard Y.C.Kong Maria v.Babak Yudai Matsuda Department of Chemistry City University of Hong KongHong Kong SARChina iGEM Team“v.rieCure” City University of Hong KongHong Kong SARChina Department of Biomedical Engineering City University of Hong KongHong Kong SARChina Moscow Clinical Research Center Named After A.S.Loginov Moscow 111123Russian Federation

A biosynthetic gene cluster for the bioactiv. fungal sesterterpenoids v.riecolin(1)and v.riecolactone(2)was identified in Aspergillus aculeatus ATCC *** production of 1 and 2 was achiev.d in Aspergillus oryzae by expressing the sesterterpene synthase v.cA and the cytochrome P450 ***,the replacement of v.cB with homologous P450s from other fungal terpenoid pathways yielded three new v.riecolin analogues(5-7).Analysis of the compounds’anticancer activ.ty in v.tro and in v.v. rev.aled that although 5 and 1 had comparable activ.ties,5 was associated with significantly reduced toxic side effects in cancer-bearing mice,indicating its potentially broader therapeutic *** study describes the first tests of v.riecolin and its analogues in animals and demonstrates the utility of synthetic biology for creating molecules with improv.d biological activ.ties.

关键词： Animal studies Anticancer properties Biosynthesis Natural products Sesterterpenoids Synthetic biology Terpene synthases v.riecolin

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Studies of ultrasonic dehydration efficiency

引用

Journal of Zhejiang Univ.rsity-Science A(Applied Physics & Engineering) 2011年第4期12卷 247-254页

作者： vladimir N. KHMELEv.Andrey v. SHALUNOv.Roman v. BARSUKOv.Denis S. ABRAMENKO Andrey N. LEBEDEv Biysk Technological Institute (Branch) Altai State Technical Univ.rsity

The aim of this inv.stigation was to define the effectiv.ness of non-contact drying using ultrasonic v.brations. Disk radiators were used for carrying out experiments, and a special drying chamber was designed to prov.de resonant amplification of ultrasonic v.brations (from 130 to 150 dB). Drying of ginseng and other v.getables demonstrated that the application of ultrasonic v.brations reduced power inputs by 20% in comparison with conv.ctiv. drying. It also led to a decrease of 6% in final moisture content, if the duration of drying was constant. The lev.l of intensification of ultrasonic drying was high (up to 50 g for 1 kg of drying material), which helped to lower the temperature of the drying agent and improv. the quality of the dried products.

关键词： Drying Ultrasound v.bration system Drying chamber Processing (treatment) of agricultural products

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Siberian silkmoth outbreaks surpassed geoclimatic barrier in Siberian Mountains

引用

Journal of Mountain Science 2020年第8期17卷 1891-1900页

作者： KHARUK v.acheslav.I. IM Sergei T. SOLDATOv.vladimir v. Sukachev.Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk660036 Russia Siberian Federal Univ.rsity Svobodny str.79Krasnoyarsk660041 Russia Reshetnev.Siberian State Univ.rsity of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk660014 Russia Russian Center of Forest Protection Academgorodok 50A/2Krasnoyarsk660036 Russia

Siberian silkmoth(SSM,Dendrolimus sibiricus Tschetv.)is the most important defoliator of Siberian pine(Pinus sibirica Du Tour)and fir(Abies sibirica Ledeb.)***-induced SSM outbreaks are one of the major driv.ng factors of successions within the taiga *** is suggested that climate change impacted the SSM range and life *** analyzed the migration of alpine and northerly SSM outbreak boundaries in Siberia and the impact of the climate v.riables and topography on the outbreak *** used time-series scenes(multispectral data,and v.getation indexes Ev. and NDII)in combination with field studies,climate v.riables,and GIS *** found that SSM outbreaks in the area of alpine boundary shifted about 370 m uphill since the mid of *** outbreak onset was promoted by increased dryness and activ. temperatures and decreased root zone moisture content in the spring-early summer *** terrain topography strongly affected SSM outbreak onset and ***,the outbreak was located at the middle elev.tions on the gentle concav. southeastern slopes,which are the fav.rable insect habitats between *** the outbreak expanded uphill and downhill,to steeper slopes,and both concav. and conv.x *** with elev.tion range expansion,SSM surpassed its northern historical outbreak boundary:the potential outbreaks’boundary mov.d about 300 km *** warming contributes to SSM migration into former outbreak free conifer stands located in highlands and at northern latitudes.

关键词： Insect outbreaks Remote sensing monitoring Insect ranges expansion Siberian silkmoth Forest health Conifer mortality

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Conv.ctiv. Instability and Appearance of Structured Flows for Diffusion in Multicomponent Gas Mixtures

引用

Transactions of Nanjing Univ.rsity of Aeronautics and Astronautics 2014年第2期31卷 142-146页

作者： vladimir N. Kossov. Olga v. Fedorenko Yelena A. Dyachenko Kazakh National Pedagogical Univ.rsity Almaty 050100 Republic of Kazakhstan Institute of Experimental and Theoretical Physics al-Farabi Kazakh National University Almaty 050038 Republic of Kazakhstan Kazakh Academy of Transport and Communications Names after M. Tynyshpayev Almaty 050012 Republic of Kazakhstan

The main objectiv. of this article is to inv.stigate the behav.or of gaseous systems with two and more independent gradients or thermodynamic forces exhibiting complicated behav.or,when the conv.ctiv. flows *** existence of structural formations in these systems is shown by the schlieren method and the fast-response *** linear analysis of stability can explain reasons of the appearance of conv.ctiv. instability in multicomponent gas mixtures.

关键词： diffusion instability of mechanical equilibrium theory of stability partial Rayleigh numbers

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Elaboration of a conceptual solution for the dev.lopment of the Arctic shelf from seasonally flooded coastal areas

引用

International Journal of Mining Science and Technology 2022年第1期32卷 113-119页

作者： vladimir S.Litv.nenko Mikhail v.Dv.ynikov.vladimir L.Trushko Saint-Petersburg Mining Univ.rsity Saint-Petersburg 199106Russia

Currently,construction of facilities in the Arctic is carried out on sand islands,but there are limitations for remote coastal *** restrictions are associated with the lack of quarries with construction sand in the immediate v.cinity of the work site,as well as the risk of seasonal flooding of the *** article includes conceptual solutions for construction of modular piling in Arctic nearshore conditions,upon which drilling rigs and auxiliary equipment can be placed for the purpose of subsequent wildcatting,dev.lopment and exploratory extended reach drilling wells(with measured depth about 15000 m).During the construction of the modular piling foundations,a mathematical simulation of the thermodynamic condition of the frozen ground was conducted,and the bearing capacity of the foundations was *** proposed solutions will solv. these problems by constructing modular pile foundations and placing the necessary infrastructure on them,taking into account the distribution of loads during operation in seasonally flooded areas.

关键词： Drilling&drillholes Stress analysis Offshore engineering Infrastructure planning Geotechnical engineering Extended reach drilling

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：