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131.
基于空间向量积分法建立了共轴涡旋结构载流线圈的解析模型,计算了磁场及磁力,并对特殊取值下的磁场空间分布进行了数值分析和讨论。基于仿真结果,提出线圈密绕情况下的近似模型并进行了相应的误差分析。结果表明,所提模型可有效地直接对磁场分布进行近似,但需对受力近似进行一定的补偿。 相似文献
132.
Zhongyu Mou Prof. Takashi Kubo Prof. Miklos Kertesz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(50):18230-18236
Homogeneous π‐stacking dimers of phenalenyl and its derivatives have gained tremendous interest as components of conducting organic materials. For the first time, we investigate theoretically heterogeneous phenalenyl π‐dimers. Key parameters, including charge transfer, interaction energy, singly occupied molecular orbital (SOMO) energy, and spin density, are studied with the help of density functional theory. We find that the amount of charge transfer between the two monomers in phenalenyl π‐dimers correlates with the difference in the SOMO energies of the constituent monomers, where the SOMO energy plays the role of a monomer (group) electronegativity index. Charge transfer plays an important role in stabilizing the heterodimers while maintaining a significant diradicaloid character. For five heterodimers the interaction energy is found to be as large as ?30 to ?50 kcal mol?1. The presented correlation between the monomer SOMO energy levels and their stability can provide a simple predictive tool to design new highly stable π‐stacking heterodimers. 相似文献
133.
分析了外加应力对光纤消光比的影响,对封装后的光纤线圈建立了简化的力学模型。根据弹性力学原理,利用有限元分析方法对其进行热应力分析,结果表明通过减小胶粘剂的热变形量可以减小对光纤的热应力影响。此外还进行了实验验证,所得实验结果与理论分析基本符合。 相似文献
134.
135.
A new device designed for both volumetric and surface NQR detection of substances spatially located in several positions,
and in the presence of environmental interference, is described. The device consists of two probe coils, placed on the same
detection plane, for excitation and detection of NQR signals. Experimental results obtained using Strong Off Resonance Comb
(SORC) pulse sequences, for the excitation of the ν- transition in samples of Sodium Nitrite (NaNO
2), are presented. It is shown that, when the total signals induced in each coil are properly combined, the interference commonly
detected in both coils is attenuated relative to the NQR signal detected by either one or both probe coils. NQR signal can
be detected by either one or both coils, but in both cases the noise induced by distant environmental sources is attenuated.
These files correspond to the revised version of the paper N° O-G-6, entitled “Pulsed 14N NQR device designed to detect substances in the presence of environmental noise” presented at the XVII International symposium
on Nuclear Quadrupole Interactions, held in Bonn, Germany in 2004.
Argentinian and International patents pending. 相似文献
136.
Bioinorganic chemists aspire to achieve the same exquisite and highly controlled inorganic chemistry featured in biology. An exciting mimetic approach involves the use of miniature artificial protein scaffolds designed de novo (often based on the coiled coil (CC) scaffold), for reproducing native metal ion sites and their function. Recently, there is increased interest, instead, in the design of xeno‐metal sites within CC assemblies. This involves incorporating either non‐biological metal ions, cofactors or non‐proteinogenic amino acid ligands for metal ion coordination, whilst retaining a minimal CC protein scaffold. Using this approach, one should be able to create functional designs with unique and unusual properties, which combine the advantages of both biology and ‘traditional’ non‐biological inorganic chemistry. It is the recent progress with respect to the design of xeno‐metallo CCs which will be discussed in this Focus Review. 相似文献
137.
20 T以上强磁场在高场科学工程中有着不可替代的作用. 电工研究所正在研制一个25 T全超导磁体系统, 包括15 T背景磁场和10 T高温超导内插磁体. 在磁体的设计和优化中, 线圈的数量和种类对于最终优化结果十分关键. 为了研究磁体数量和磁体相关参数的关系, 计算了20 组不同的线圈组合下磁体的优化结果. 优化中除了考虑必要的限制条件以外, 还采用了一种结合局部优化算法和全局优化算法的方法. 通过对比分析发现, 线圈数量和磁体造价之间, 存在一个“V”形的关系. 更进一步地, 本文分析了不同超导体在磁体中应该贡献的最佳磁场, 以及背景磁体统一供电给优化结果带来的影响. 相似文献
138.
设计了HL-2M环向场线圈基本形状、特殊的指形接头和斜面接头以及馈线、绝缘结构和水冷回路。每个环向场线圈由L形中心段、上弧段和外弧段分别通过指形接头和斜面接头组装成完整的D形线圈。分段可拆卸的D形线圈结构可以使得真空室和单个极向场线圈分别整体吊装到环向场线圈内侧。单根引线和双回线的馈线结构既能节省装置空间,又能降低杂散磁场。TF线圈匝间绝缘500V,对地绝缘30kV。采用软焊在线圈旁侧槽内的铜管对线圈进行水冷以带走线圈放电产生的焦耳热。 相似文献
139.
The optimization problem for coil arrays is largely unsolved, even for the case of a two-coil system. This paper reports a systematic computer simulation to investigate the maximal achievable signal-to-noise ratio (SNR) with a two-coil receiver system where, using cancellation circuitry, mutual inductance is made zero. Both symmetrical and asymmetrical solutions with respect to two-coil geometry are considered. SNR is measured at a single point at a certain depth and also along a longitudinal or transverse line at the same depth. The conducting medium containing these regions of interest is assumed to be an infinite half space, an infinite cylinder or a finite sphere. The previous coil array design using a "magical" overlap only approximates the optimal solution for the infinite half space. For the infinite cylinder and the finite sphere, optimal solutions can be quite different from the "magical" overlap. 相似文献
140.