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41.
《Comptes Rendus Physique》2015,16(9):819-835
Monolayer- and compact-multilayer-stacked ingestible TX coils are investigated for ingestible capsule systems. The inductive link through the human body is modeled. The efficiency of the near-field magnetic induction link budget is evaluated in the air, in the homogeneous human body and in the three-layer human body. The variations of the position and the orientation of the TX capsule coil are taken into account to evaluate the coupling response between the TX ingestible and RX on-body coils. 相似文献
42.
The DC and inverter characteristics for the position of a single grain boundary (GB) in a nanosheet gate-all-around (GAA) MOSFET based on poly-crystalline silicon with three channels were analyzed. For the same channel layer, owing to the band banding by the drain voltage, the GB displays decreasing influence on the current as it moves towards the drain. The GB exhibits the highest on-state current of 6.89 × 10−4 A/μm when it is located at the drain. The DC characteristics determine the noise margin and delay time of the inverter. The higher the induced current, the lower the noise margin and delay time of the NMOS leading to improved characteristics of the inverter. The delay time when the GB existed in the drain, was considered to be the best in terms of DC performance as it was the lowest at 6.47 ps and showed 8.3% improvement in the switching characteristics. 相似文献
43.
Excitation function and mean projected recoil ranges of nuclei produced in the12C-induced reactions on51V target were measured by conventional stacked foil and thick-target thick-recoil-catcher technique for bombarding energiesE ≤ 84 MeV for12C ion beam. The measured recoil ranges are converted to momentum transfer. Information on momentum transfer was used to get
clues about some aspects of the interaction such as complete fusion which corresponds to full momentum transfer and incomplete
fusion reaction mechanism. The measured excitation functions are compared with the calculation based on the statistical model
which describes only equilibrium decay of the compound nucleus using the Cascade code and the geometry dependent hybrid model
which describes equilibrium as well as pre-equilibrium decay of the compound nucleus using the Alice/91 code. The measured
excitation functions and average ranges of the radioisotope products of the reactions12C on51V indicate that the three separate reaction mechanisms could be attributable to complete fusion of12C, incomplete fusion of8Be and incomplete fusion of4He respectively with the target. The8Be and4He are the break-up component of12C into8Be +4He. The predictions of the codes, especially the Cascade, generally agree with the measured cross-sections which could be
attributed to complete fusion of12C with the target51V. 相似文献
44.
Capacitive coupling effects in some circular stacked inductors are studied in this paper, by taking into account the possible
incomplete overlapping and cross-overlapping between up and bottom tracks of different layers. Formulas are derived for extracting
the equivalent capacitance of double-and multi-spiral circular inductors with integral and fractional number of turns. Compared
with the full-wave and the analytical methods with the completely overlapping assumption, the proposed method can predict
equivalent capacitance and self-resonance frequency (f
SR
) accurately for on-chip circular stacked inductors used in the design of RFICs. 相似文献
45.
We evaluated the collimated beam quality of a planar microlens (PML) for parallel optical interconnect systems. It has been confirmed that the divergence beam from a single mode fiber was collimated by single PML and propagated with good beam quality by about 10 mm, which is the nominal length of microoptics components considered. The divergence beam from a vertical cavity surface emitting laser was collimated using stacked PML and the collimated beam width of 100 μm was obtained. The collimated beam profile was good enough for low loss beam interconnect in a micro-optical bench scheme. 相似文献
46.
研究了一种结构紧凑型的多级层叠Blumlein纳秒脉冲形成线,从理论上分析了放电时回路各分布参数对层叠Blumlein脉冲形成线输出电压的影响,并利用PSpice模拟验证了各分布参数对层叠Blumlein脉冲形成线输出结果的影响,发现开关的导通电阻是制约输出电压幅值的主要因素,开关的分布电感对输出波形的影响大于负载分布电感的影响,基于时域有限差分法原理,利用XFDTD软件模拟了两级层叠Blumlein线的电磁耦合效应。开展了多级层叠Blumlein脉冲形成线实验,结果表明,基于陶瓷固态传输线和GaAs光导开关的层叠Blumlein脉冲形成线能够实现输出电压叠加,可用于产生ns量级脉宽的脉冲高压。 相似文献
47.
Analysis and applications of a frequency selective surface via a random distribution method
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A novel frequency selective surface (FSS) for reducing radar cross section (RCS) is proposed in this paper. This FSS is based on the random distribution method, so it can be called random surface. In this paper, the stacked patches serving as periodic elements are employed for RCS reduction. Previous work has demonstrated the efficiency by utilizing the microstrip patches, especially for the reflectarray. First, the relevant theory of the method is described. Then a sample of a three-layer variable-sized stacked patch random surface with a dimension of 260 mm x 260 mm is simulated, fabricated, and measured in order to demonstrate the validity of the proposed design. For the normal incidence, the 8-dB RCS reduction can be achieved both by the simulation and the measurement in 8 GHz-13 GHz. The oblique incidence of 30° is also investigated, in which the 7-dB RCS reduction can be obtained in a frequency range of 8 GHz-14 GHz. 相似文献
48.
V. Vittoria 《Journal of Macromolecular Science: Physics》2013,52(3-4):489-502
Smectic isotactic polypropylene films were annealed at different temperatures for different times. Density, wide-angle x-ray scattering (WAXS), differential scanning calorimetry, and the transport properties of methylene chloride vapor were used to follow the transformation of the smectic phase into the monoclinic phase. The results of WAXS diffractograms indicate different saturation levels of crystallization with the maximum order attained progressively more quickly at higher temperatures. Density measurements, however, show that, after a first saturation level, a further increase of this parameter occurs after long annealing times; and this second step is lower, the higher the temperature. Sorption and diffusion, analyzed to investigate the amorphous component, show that annealing the smectic phase at 50°C results in a decrease of amorphous fraction without transformation of the smectic phase. The transition from smectic to monoclinic phase occurs at temperatures higher than 60°C. During the annealing at 80°C there is first a decrease of amorphous fraction corresponding to the first saturation level of the density, and then a further decrease of amorphouse phase corresponding to the final increase of density after 24 hr of annealing. 相似文献
49.
Yusheng Dou Shuai Yuan Wenying Zhang Hong Tang Glenn V. Lo 《Molecular physics》2013,111(14):1517-1524
The nonradiative decay of a π-stacked adenine and thymine, following excitation of thymine by an ultrafast laser pulse, was studied by semiclassical dynamics simulations. The simulation found that a bonded exciplex is formed after excitation due to strong interaction between the stacked bases. The strong interaction significantly lowers the energy gap between the LUMO and HOMO and consequently facilitates the deactivation of the electronically excited molecule. It also restricts the deformation vibration of the excited thymine molecule, which slows down the coupling between the HOMO and LUMO energy levels and delays the deactivation of the excited adenine molecule to the electronic ground state. 相似文献
50.
有机太阳电池由于质轻、价廉、柔性,受到人们的广泛关注.单个有机材料只能吸收部分太阳光,叠层结构的太阳电池将不同吸收带隙的有机材料通过中间层连接起来,既能充分吸收太阳光,又能提高太阳电池的开路电压或短路电流.本文综述了近年来有机共混结构叠层太阳电池的研究进展,介绍了各种叠层有机太阳电池的结构、原理及性能,阐述了国内外有机叠层太阳电池研究的现状及存在问题,为高性能有机太阳电池的研究提供有价值的参考. 相似文献