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One new fractional-order chaos system and its circuit simulation by electronic workbench 被引量:1
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作者 周平 程雪峰 张年英 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第9期3252-3257,共6页
This paper proposes a new chaotic system and its fractional-order chaotic system. The necessary condition for the existence of chaotic attractors in this new fractional-order system is obtained. It finds that this new... This paper proposes a new chaotic system and its fractional-order chaotic system. The necessary condition for the existence of chaotic attractors in this new fractional-order system is obtained. It finds that this new fractional-order system is chaotic for q 〉 0.783 if the system parameter m=6. The chaotic attractors for q=0.8, and q=0.9 are obtained. A circuit is designed to realize its fractional-order chaos system for q=0.9 by electronic workbench. 展开更多
关键词 fractional-order chaotic systems necessary condition electronic workbench
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Integrating Electronic Systems for Requesting Clinical Laboratory Test into Digital Clinical Records: Design and Implementation
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作者 Félix Gascón Luna Isidoro Herrera Contreras +1 位作者 Antonio Cruz Guerrero Francisco Bermudo Guitarte 《Health》 2017年第4期622-639,共18页
Clinical laboratory tests are basic elements that support healthcare tasks such as disease detection, diagnosis and monitoring of response to treatments. Current laboratory information systems focus on the patient dat... Clinical laboratory tests are basic elements that support healthcare tasks such as disease detection, diagnosis and monitoring of response to treatments. Current laboratory information systems focus on the patient database, tests and results, with multiple modules available, connecting with the various analytical systems or work areas. However laboratory information systems functioned as “islands of information”, because their design was fundamentally inward-looking and disconnected from other healthcare computer applications. Actually, the Electronic Health Register (EHR) is considered by clinicians as a tool with great potential healthcare benefits. The EHR, in the sense of a unique and complete record of a patient’s healthcare and state of health, regardless of the healthcare level used, is a real attempt to eliminate these “islands of information” and need modules to act as “bridges” with the laboratory information systems. This type of module, which in generic terms may be referred to as a laboratory test request module, has become an essential feature of the EHR. These modules need to use a laboratory coding system as a common language for exchanging information, ensuring that tests and results are unequivocally identified. The development of the laboratory test request module requires the commitment of professionals and political authorities, being necessary time for their design and an adequate pilot phase. The laboratory professionals have to assume a leadership role in the whole process of design, development and implementation of these modules, integrating in the equipment of information technologies of healthcare providers. In our manuscript we review the elements that may prove electronic systems for requesting clinical laboratory test into digital clinical records and the key elements to move from theory to practice. 展开更多
关键词 electronic Health RECORDS LABORATORY Information systemS TEST Request Module Medical Order Entry systemS systemS Integration LABORATORY TEST Codes systematic NOMENCLATURE
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Characterization of local chemical ordering and deformation behavior in high entropy alloys by transmission electron microscopy
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作者 Qiuhong Liu Qing Du +7 位作者 Xiaobin Zhang Yuan Wu Andrey A.Rempel Xiangyang Peng Xiongjun Liu Hui Wang Wenli Song Zhaoping Lü 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期877-886,共10页
Short-range ordering(SRO)is one of the most important structural features of high entropy alloys(HEAs).However,the chemical and structural analyses of SROs are very difficult due to their small size,complexed composit... Short-range ordering(SRO)is one of the most important structural features of high entropy alloys(HEAs).However,the chemical and structural analyses of SROs are very difficult due to their small size,complexed compositions,and varied locations.Transmission electron microscopy(TEM)as well as its aberration correction techniques are powerful for characterizing SROs in these compositionally complex alloys.In this short communication,we summarized recent progresses regarding characterization of SROs using TEM in the field of HEAs.By using advanced TEM techniques,not only the existence of SROs was confirmed,but also the effect of SROs on the deformation mechanism was clarified.Moreover,the perspective related to application of TEM techniques in HEAs are also discussed. 展开更多
关键词 high entropy alloys transmission electron microscopy short-range ordering deformation mechanisms
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The Correlation between the Zeroth-Order General Randic Indices and the π-Electronic Energies of Hexagonal Systems
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作者 郑洁 王贤真 《Journal of Donghua University(English Edition)》 EI CAS 2011年第6期559-562,共4页
A formula was proved for computing the zeroth-order general Randic index of a hexagonal system to explore the correlation between the zeroth-order general Randic index and the π-electronic energy of a hexagonal syste... A formula was proved for computing the zeroth-order general Randic index of a hexagonal system to explore the correlation between the zeroth-order general Randic index and the π-electronic energy of a hexagonal system.As a consequence,the extremal hexagonal systems with minimum or maximum zeroth-order general Randic index were completely characterized.Moreover,by using the least-square fit method and regression analysis,a new and close relation was found between the zeroth-order general Randic index and the π-electronic energy of a hexagonal system.So the zeroth-order general Randic index is a good measure of the π-electronic energies for benzenoid hydrocarbons. 展开更多
关键词 hexagonal system zeroth-order general Randic index π-electronic energy correlation coefficient
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双偶氮苯-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子的二阶非线性光学性质 被引量:1
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作者 张宇红 李博 +4 位作者 陈自然 李渊 徐友辉 张莉萍 何旭东 《原子与分子物理学报》 CAS 北大核心 2025年第2期15-23,共9页
使用密度泛函理论(DFT)M06-2X方法、采用6-311+g(d,p)基组,分别对26个双偶氮-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子进行结构优化与频率计算;使用含时密度泛函理论(TD-DFT)TD-M06-2X方法计算了a1~d6分子的前线分子轨道与... 使用密度泛函理论(DFT)M06-2X方法、采用6-311+g(d,p)基组,分别对26个双偶氮-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子进行结构优化与频率计算;使用含时密度泛函理论(TD-DFT)TD-M06-2X方法计算了a1~d6分子的前线分子轨道与电子吸收光谱,采用有效场FF方法研究了二阶非线性光学性质(NLO).研究结果表明,26个噻蒽四酮类衍生物分子的能隙在1.33—2.02 eV范围,归属于有机半导体;最低能量吸收峰波长在601.8~609.5nm范围;在增大分子的二阶非线性光学系数β_(μ)(或β_(0))值方面,含相同偶氮苯基团或含不同偶氮苯基团分别引入到二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮分子两侧的2,10位优于2,9位,在2,10位分别端接含推、拉基团的偶氮苯优于含相同给电子基团的偶氮苯.在偶氮苯苯环对位分别端接强吸电子基(-NO_(2))与强供电子基(如-N(CH_(3))_(2)、-N(Ph)_(3)、-N-苯基咔唑等)可增强体系的二阶非线性光学性能,获得性能良好的非线性光学材料. 展开更多
关键词 双偶氮 二苯并[b i]噻蒽-[2 3-b]苯-5 7 12 14-四酮 密度泛函理论 电子吸收光谱 二阶非线性光学性质
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电子订货系统(EOS)在医用材料管理中的应用 被引量:4
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作者 任晓敏 唐荣高 +2 位作者 罗志勇 朱秀丽 张彪 《生物医学工程学进展》 CAS 2017年第2期112-115,共4页
该文探讨了医院设备科库房医用材料自动补货问题,尝试将物流EOS系统与现有的医院"HIS系统"和"物资管理系统"相结合,优化了相关领域与订货流程,从而建立一套实用、科学、符合医院实际情况的基于物流系统的医用材料... 该文探讨了医院设备科库房医用材料自动补货问题,尝试将物流EOS系统与现有的医院"HIS系统"和"物资管理系统"相结合,优化了相关领域与订货流程,从而建立一套实用、科学、符合医院实际情况的基于物流系统的医用材料管理方法。 展开更多
关键词 电子订货系统(eos) 物资管理 库存周转率
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噻吩酰亚胺衍生物二阶非线性光学性质的DFT研究
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作者 蔺彬彬 闫慧君 《原子与分子物理学报》 CAS 北大核心 2025年第1期20-28,共9页
采用密度泛函理论(DFT)CAM-B3LYP方法,计算研究了12个设计的噻吩酰亚胺衍生物的电子光谱和二阶非线性光学性质.结果表明,此类化合物有较大的第一超极化率β_(tot)值和β_(vec)值,且β_(tot)值和β_(vec)值随引入氰基数目的增加而显著增... 采用密度泛函理论(DFT)CAM-B3LYP方法,计算研究了12个设计的噻吩酰亚胺衍生物的电子光谱和二阶非线性光学性质.结果表明,此类化合物有较大的第一超极化率β_(tot)值和β_(vec)值,且β_(tot)值和β_(vec)值随引入氰基数目的增加而显著增大.给/吸电子基团引起的电荷转移变化对体系β_(tot)值和β_(vec)值的影响大于分子六元杂环中N杂原子位置变化对其影响. 展开更多
关键词 噻吩酰亚胺衍生物 密度泛函理论 二阶非线性光学性质 电子光谱
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Effective Doping of Rare-earth Ions in Silica Gel:A Novel Approach to Design Active Electronic Devices 被引量:1
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作者 D.Haranath Savvi Mishra +2 位作者 Amish G.Joshi Sonal Sahai Virendra Shanker 《Nano-Micro Letters》 SCIE EI CAS 2011年第3期141-145,共5页
Eu^(3+)luminescence spectroscopy has been used to investigate the effective doping of alkoxide-based silica(SiO_2) gels using a novel pressure-assisted sol-gel method. Our results pertaining to intense photoluminescen... Eu^(3+)luminescence spectroscopy has been used to investigate the effective doping of alkoxide-based silica(SiO_2) gels using a novel pressure-assisted sol-gel method. Our results pertaining to intense photoluminescence(PL) from gel nanospheres can be directly attributed to the high specific surface area and remarkable decrease in unsaturated dangling bonds of the gel nanospheres under pressure. An increased dehydroxylation in an autoclave resulted in enhanced red(~611 nm) PL emission from europium and is almost ten times brighter than the SiO_2 gel made at atmospheric pressure and^50 using conventional St¨ober-Fink-Bohn process. The presented results are entirely different from those reported earlier for SiO_2:Eu3+gel nanospheres and the origin of the enhanced PL have been discussed thoroughly. 展开更多
关键词 LUMINESCENCE NANOPHOSPHOR Short-range order Electron microscopy
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Connection between Physical Properties in Homologous Series of Molecular Systems 被引量:1
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作者 Dolomatov Michail Yurievich Dezortsev Sergey Vladislavovich 《Journal of Chemistry and Chemical Engineering》 2013年第6期566-572,共7页
The connections between different physical-chemical properties in homologous molecular series are analyzed from the quantum-mechanic and the algebraic theory points of view and are explained by influence of the gage t... The connections between different physical-chemical properties in homologous molecular series are analyzed from the quantum-mechanic and the algebraic theory points of view and are explained by influence of the gage to the quantum electronic continuum. The connection between quantum and macroscopic properties of the substances is confirmed in homologous series of n-alkanes. Linear correlation between the coefficient of magnetization and energy of the highest occupied molecular orbital in homologous series of n-alkanes C2-C10 is established. The connection between diamagnetic and electronic characteristics of n-alkanes with the temperatures of the first order phase transitions (melting point) and other physical-chemical properties were discovered. The nature of interconnection between critical and diamagnetic properties of n-alkanes C2-C10 and results of previous works allow to suppose significant role of the spin interactions in electronic continuum states along the process of the first order phase transitions. 展开更多
关键词 N-ALKANES electronic structure physical-chemical properties band gap width first order phase transitions coefficient ofmagnetization.
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Electronic structure of Au-Cu alloys 被引量:1
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作者 余方新 谢佑卿 +3 位作者 聂耀庄 李小波 彭红键 陶辉锦 《中国有色金属学会会刊:英文版》 CSCD 2004年第6期1041-1049,共9页
By studying the correlativity between energy, volume and electronic structure of characteristic crystals and bound conditions of OA theory, the potential energy function, atomic volume interactive function and electro... By studying the correlativity between energy, volume and electronic structure of characteristic crystals and bound conditions of OA theory, the potential energy function, atomic volume interactive function and electronic structure of Au-Cu alloys have been determined. Then following the general Vegard’s law in characteristic theory, the electronic structure and properties of disordered continue solid solution and three ordered alloys with the maximum ordering degree are calculated. It is found that the non-bonding electrons and near-free electrons in outer shell will transform to covalent electrons during alloying. By analyzing the variation of electronic structure and cohesion of ordering and disordered alloys, the transformation of order-disorder transition Au-Cu alloy has been studied. 展开更多
关键词 电子结构 金-铜合金 CC 排序变换 原子体积
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Charge ordering modulations in a Bi_(0.4)Ca_(0.6)MnO_3 film with a thickness of 110 nm
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作者 丁艳华 王乙潜 +2 位作者 蔡鎔声 陈允忠 孙继荣 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期482-486,共5页
The low temperature sample stage in a transmission electron microscope is used to investigate the charge ordering behaviours in a Bi0.4Ca0.6MnO3 film with a thickness of 110 nm at 103 K. Six different types of superla... The low temperature sample stage in a transmission electron microscope is used to investigate the charge ordering behaviours in a Bi0.4Ca0.6MnO3 film with a thickness of 110 nm at 103 K. Six different types of superlattice structures are observed using the selected-area electron diffraction (SAED) technique, while three of them match well with the modulation stripes in high-resolution transmission electron microscopy (HRTEM) images. It is found that the modulation periodicity and direction are completely different in the region close to the Bi0.4Ca0.6MnO3/SrTiO3 interface from those in the region a little further from the Bi0.4Ca0.6MnO3/SrTiO3 interface, and the possible reasons for this are discussed. Based on the experimental results, structural models are proposed for these localized modulated structures. 展开更多
关键词 charge ordering selected-area electron diffraction high-resolution transmission electron microscopy pulsed laser deposition
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First-principles study of orbital ordering in cubic fluoride KCrF_3
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作者 明星 熊良斌 +3 位作者 徐火希 杜菲 王春忠 陈岗 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期514-517,共4页
Comprehensive first-principles calculations are performed to provide insight into the intriguing physical properties of the ternary cubic fluoride KCrF3. The electronic structures exhibit a prominent dependence on the... Comprehensive first-principles calculations are performed to provide insight into the intriguing physical properties of the ternary cubic fluoride KCrF3. The electronic structures exhibit a prominent dependence on the effective local Coulomb interaction parameter Ueff. The ground state of the cubic phase is a ferromagnetic (FM) half-metal with Ueff equal to 0, 2, and 4 eV, whereas the insulating A-type antiferromagnetic (A-AFM) state with concomitant homogeneous orbital ordering is more robust than the FM state for Ueff exceeding 4 eV. We propose that the origin of the orbital ordering is purely electronic when the cooperative Jahn-Teller distortions are absent in cubic KCrF3. 展开更多
关键词 electron density of states band structure orbital ordering first-principles calculations
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Magnetic Properties of Perovskite Manganite La_ (0.3)Ca_ (0.7)Mn_ (0.96)W_ (0.04)O_3 in Charge Ordering Phase
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作者 彭振生 郭焕银 +1 位作者 严国清 毛强 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期251-254,共4页
The sample La_ 0.3Ca_ 0.7Mn_ 0.96W_ 0.04O_3 was prepared by the solid-state method. Magnetic properties of La_ 0.3Ca_ 0.7Mn_ 0.96W_ 0.04O_3 was studied through the measurement of M-T curve, M-H curves and ESR curves o... The sample La_ 0.3Ca_ 0.7Mn_ 0.96W_ 0.04O_3 was prepared by the solid-state method. Magnetic properties of La_ 0.3Ca_ 0.7Mn_ 0.96W_ 0.04O_3 was studied through the measurement of M-T curve, M-H curves and ESR curves of the sample. The results show that: charge ordering (CO) phase forms at 265 K; the system exhibits paramagnetism when T>265 K; it exhibits long-range anti-ferromagnetism (there is a little FM component in AFM background) and the coexistence of a little FM phase and AFM/CO phase forms when T<225 K; the system transforms from paramagnetism to antiferromagnetism in charge-ordering state with temperature decreasing from 265 to 225 K. The width of ESR spectrum line of the sample La_ 0.3Ca_ 0.7Mn_ 0.96W_ 0.04O_3 was measured, and the value of the line width of paramagnetic resonance ΔH_ PP increases with temperature decreasing, which indicates that ferromagnetic connection of the sample strengthens with temperature decreasing. 展开更多
关键词 MANGANITE La_ 0.3Ca_ 0.7Mn_ 0.96W_ 0.04O_3 charge ordering electron paramagnetic resonance magnetic properties
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ORDERING OF VACANCIES IN RAPIDLYQUENCHED TiNi SHAPE MEMORY ALLOY
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作者 WANG Shidong LAM Cheungching +2 位作者 SHEN Guangjun ZHANG Jinping WU Xiaozhen (Southeast University, Nanjing,China)(City Polytechnic of Hong Kong, Hong Kong) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1995年第3期162-166,共5页
The modification of the electron diffraction pattern(EDP) of B2 in an as rapidly quenched then short time aged Ti Ni shape memory alloy(SMA) has been studied systematically using TEM. It was found that the diffusio... The modification of the electron diffraction pattern(EDP) of B2 in an as rapidly quenched then short time aged Ti Ni shape memory alloy(SMA) has been studied systematically using TEM. It was found that the diffusion scattering rings in EDP of an as rapidly quenched Ti-Ni SMA is associated with short range order (SRO) of vancancies in parent B2. After aging at 450℃ for 5 min the diffusion scattering rings are replaced by 1/2 {001} and 1 / 4 {012} extra reflections. It indicates that the SRO of vacancies has transformed into long range order (LRO) of vacancies,moreover,the LRO of vacancies exists in microdomains. 展开更多
关键词 Ti Ni shape memory alloy vacancy order electron diffraction
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Theoretical Study on the Effect of Multiband Structure on Critical Temperature and Electronic Specific Heat in SmOFeAs Iron Pnictide Superconductor
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作者 Shamin Masih Piyush Masih Sarita Khandka 《Journal of Applied Mathematics and Physics》 2022年第7期2232-2244,共13页
In the present theoretical work, superconducting order parameter (&#8710;) and electronic specific heat (C<sub>es</sub>) of SmOFeAs iron pnictide (IP) superconductor has been studied using multiband (M... In the present theoretical work, superconducting order parameter (&#8710;) and electronic specific heat (C<sub>es</sub>) of SmOFeAs iron pnictide (IP) superconductor has been studied using multiband (MB) model of IP superconductors. Attempt has been made to use the MB structure of IP superconductors and expressions for critical temperature (T<sub>c</sub>) and C<sub>es</sub> are obtained, calculations being made for one, two and three bands of SmOFeAs. It has been found that MB results are close to the experimental value of T<sub>c</sub> for this compound. C<sub>es</sub> calculations show jump of 1.5 × 10<sup>-5</sup> eV/atom K, 4 × 10<sup>-5</sup> eV/atom K and 4 × 10<sup>-5</sup> eV/atom K for one, two and three band models respectively. The study brings out the importance of MB structure in IPs, highlighting the fact that increasing the number of bands, increases T<sub>c</sub>. The specific heat jump (&#8710;C) does not correspond to the BCS value, thereby proving that IPs are unconventional in nature. 展开更多
关键词 electronic Specific Heat Iron Pnictide Superconductor MULTIBAND Superconducting Order Parameter
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Electronic Absorption Spectra and Third-Order Nonlinear Optical Property of Dinaphtho[2,3-b:2’,3’-d]Thiophene-5,7,12,13- Tetraone (DNTTRA) and Its Phenyldiazenyl Derivatives: DFT Calculations 被引量:1
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作者 Ziran Chen Yujin Zhang +3 位作者 Zhanrong He Yonghua Guan Yuan Li Hongping Li 《Computational Chemistry》 2020年第4期43-60,共18页
Third-order nonlinear optical (NLO) materials have broad application prospects in high-density data storage, optical computer, modern laser technology, and other high-tech industries. The structures and frequencies of... Third-order nonlinear optical (NLO) materials have broad application prospects in high-density data storage, optical computer, modern laser technology, and other high-tech industries. The structures and frequencies of Dinaphtho[2,3-b:2’,3’-d]thiophene-5,7,12,13-tetraone (DNTTRA) and its 36 derivatives containing azobenzene were calculated by using density functional theory B3LYP and M06-2X methods at 6-311++g(d, p) level, respectively. Besides, the atomic charges of natural bond orbitals (NBO) were analyzed. The frontier orbitals and electron absorption spectra of A-G5 molecule were calculated by TD-DFT (TD-B3LYP/6-311++g(d, p) and TD-M06-2X/6-311++g(d, p)). The NLO properties were calculated by effective finite field FF method and self-compiled program. The results show that 36 molecules of these six series are D-π-A-π-D structures. The third-order NLO coefficients γ (second-order hyperpolarizability) of the D series molecules are the largest among the six series, reaching 10<sup>7</sup> atomic units (10<sup><span style="color:#4F4F4F;font-family:-apple-system, " font-size:14px;white-space:normal;background-color:#ffffff;"="">-</span>33</sup> esu) of order of magnitude, showing good third-order NLO properties. Last, the third-order NLO properties of the azobenzene ring can be improved by introducing strong electron donor groups (e.g. -N(CH<sub>3</sub>)<sub>2</sub> or -NHCH<sub>3</sub>) in the azobenzene ring, so that the third-order NLO materials with good performance can be obtained. 展开更多
关键词 AZOBENZENE Dinaphtho[2 3-b:2’ 3’-d]Thiophene-5 7 12 13-Tetraone Density Functional Theory electronic Absorption Spectra Third-Order Nonlinear Optical Property
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Third-order polynomial model for analyzing stickup state laminated structure in flexible electronics
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作者 Xianhong Meng Zihao Wang +1 位作者 Boya Liu Shuodao Wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2018年第1期48-61,共14页
Laminated hard-soft integrated structures play a significant role in the fabrication and development of flexible electronics devices. Flexible electronics have advantageous characteristics such as soft and light-weigh... Laminated hard-soft integrated structures play a significant role in the fabrication and development of flexible electronics devices. Flexible electronics have advantageous characteristics such as soft and light-weight, can be folded,twisted, flipped inside-out, or be pasted onto other surfaces of arbitrary shapes. In this paper, an analytical model is presented to study the mechanics of laminated hard-soft structures in flexible electronics under a stickup state. Thirdorder polynomials are used to describe the displacement field,and the principle of virtual work is adopted to derive the governing equations and boundary conditions. The normal strain and the shear stress along the thickness direction in the bimaterial region are obtained analytically, which agree well with the results from finite element analysis. The analytical model can be used to analyze stickup state laminated structures, and can serve as a valuable reference for the failure prediction and optimal design of flexible electronics in the future. 展开更多
关键词 Flexible electronics Stickup state Third-order polynomials Virtual work principle
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Charge-Ordering in La_(0.33) Ca_(0.67) MnO_3 Perovskite
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作者 WANG Ren-hui GUI Jia-nian +1 位作者 Zhu Yi-mei ( Department of Physics, Wuhan University, Wuhan 430072, China Brookhaven National Laboratory, Upton, NY 11973, USA) 《Wuhan University Journal of Natural Sciences》 CAS 2000年第1期79-79,共1页
Structure model of charge-ordered La_0.33 Ca_0.67 MnO_3, perovskite is one of current focused study in condensed matter physics. There are great discrepancies in previous studies in this field. Our transmission electr... Structure model of charge-ordered La_0.33 Ca_0.67 MnO_3, perovskite is one of current focused study in condensed matter physics. There are great discrepancies in previous studies in this field. Our transmission electron microscopy study confirms Wigner crystal model with transverse displacement and is not consisent with the hi-stripe model with longitudinal displacement. We observed incommensurate modulation and anti-phase domains with a displacement vector a_co/3 in charge--ordered La_0.33 Ca_0.67 MnO_3, perovskite. 展开更多
关键词 CHARGE-ordering perovskite structure La_(0.33) Ca_(0.67) MnO_3 electron microscopy domain structure transition metal oxides colossal magnetoresistance
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基于R-L分数阶定义的CCM Flyback变换器建模与分析
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作者 王硕禾 符屹男 +2 位作者 常宇健 杨鹏 李倩 《太阳能学报》 EI CAS CSCD 北大核心 2024年第6期217-225,共9页
针对电容电感都为分数阶这一事实,利用分数阶微积分R-L定义和状态空间平均法,对工作在电感电流连续模式(CCM)下的分数阶Flyback变换器进行建模与分析。推导CCM分数阶Flyback变换器的静态工作点和小信号传递函数以及变换器工作在CCM模式... 针对电容电感都为分数阶这一事实,利用分数阶微积分R-L定义和状态空间平均法,对工作在电感电流连续模式(CCM)下的分数阶Flyback变换器进行建模与分析。推导CCM分数阶Flyback变换器的静态工作点和小信号传递函数以及变换器工作在CCM模式下的条件。其次,讨论Caputo模型与R-L导数模型的区别,得出在R-L分数阶定义下直流静态工作点不仅与占空比相关,而且还与电感和电容的阶数以及负载有关。最后,在PSIM中搭建R-L分数阶CCM Flyback变换器电路模型,得到不同分数阶电感电容阶数下分数阶Flyback变换器输出电压和电感电流的仿真波形,通过仿真结果与理论计算结果对比,验证所建模型的正确性,得出分数阶电感电容的阶数会影响闭环控制器的设计和分数阶模型能更加精确地描述Flyback变换器的工作特性。 展开更多
关键词 DC-DC变换器 电力电子 仿真平台 R-L定义 分数阶建模
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氧化物中存在O2p空穴的典型实验结果和磁性氧化物的O2p巡游电子模型
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作者 唐贵德 齐伟华 《河北师范大学学报(自然科学版)》 CAS 2024年第1期1-8,共8页
负二价氧离子具有满壳层价电子结构(2s^(2)2p^(6)).负一价氧离子的价电子结构为2s^(2)2p^(5),相当于存在1个O2p空穴.传统的凝聚态物理和材料化学研究中都假设氧化物中的氧离子全部为负二价离子,在迄今为止的绝大多数研究氧化物磁性和电... 负二价氧离子具有满壳层价电子结构(2s^(2)2p^(6)).负一价氧离子的价电子结构为2s^(2)2p^(5),相当于存在1个O2p空穴.传统的凝聚态物理和材料化学研究中都假设氧化物中的氧离子全部为负二价离子,在迄今为止的绝大多数研究氧化物磁性和电输运性质的报道中,采用关于磁有序的超交换和双交换作用模型,都没有考虑O2p空穴的影响.然而,许多价电子状态实验证明,在氧化物中存在不可忽略的O2p空穴,即存在不可忽略的负一价氧离子,其占比可达30%或更多.基于这些实验结果,对传统磁有序模型进行改进,英美学者首先进行了探讨,笔者所在课题组与中国科学院物理研究所磁学国家重点实验室合作进行了系统的研究.介绍了相关的典型实验结果和理论模型. 展开更多
关键词 磁性材料 磁有序模型 O2p空穴 电子能量损失谱 X-射线光电子谱
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