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171.
Geometric structure of N2Oq+ (q = 5, 6) studied by Ne8+ ion-induced Coulomb explosion imaging
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We report the study on the complete three-body Coulomb explosion (CE) of N2Oq+ (q = 5, 6) induced by 56-keV/u Ne8+ ion collision with N2O gaseous molecule. Six CE channels for N2O5+ and seven for N2O6+ are identified by measuring three ionic fragments and the charge-changed projectile in quadruple coincidence. Correspondingly the kinetic energy release (KER) and momentum correlation angle (MCA) distributions of three ionic fragments for each of the CE channels are also deduced. Numerical computation is presented to reconstruct the geometric structure of N2Oq+ prior to dissociation based on the measured KER and MCA. The N-N and N-O bond lengths and the N-N-O bond angles of N2Oq+ for each of the channels are determined. 相似文献
172.
Multi-window transparency and fast–slow light switching in a quadratically coupled optomechanical system assisted with three-level atoms
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We study theoretically the features of the output field of a quadratically coupled optomechanical system assisted with three-level atoms. In this system, the atoms interact with the cavity field and are driven by a classical field, and the cavity is driven by a strong coupling field and a weak signal field. We find that there exists a multi-window transparency phenomenon. The width of the transparent windows can be adjusted by controlling the system parameters, including the number of the atoms, the powers of the lasers driving the atoms and driving the cavity, and the environment temperature.We also find that a tunable switch from fast light to slow light can be realized in this system. 相似文献
173.
174.
Xiao-Yu Hu 《Frontiers of Physics》2016,11(3):114203
We study the phase sensitivity of an SU(1,1) interferometer with two input beams in the displaced squeezed vacuum state and the coherent state, respectively. We find that there exists an optimal squeezing fraction of the displaced squeezed vacuum state that optimizes the phase sensitivity. We also examine the effects of some factors, including the loss, mean photon number of the input beams and amplitude gain of the optical parameter amplifiers, on the optimal squeezing fraction so that we can choose the optimal values to enhance the phase sensitivity. 相似文献
175.
Phase sensitivity of two nonlinear interferometers with inputting entangled coherent states
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We investigate the phase sensitivity of the SU(1,1) interfereometer [SU(1,1)I] and the modified Mach–Zehnder interferometer(MMZI) with the entangled coherent states(ECS) as inputs. We consider the ideal case and the situations in which the photon losses are taken into account. We find that, under ideal conditions, the phase sensitivity of both the MMZI and the SU(1,1)I can beat the shot-noise limit(SNL) and approach the Heisenberg limit(HL). In the presence of photon losses, the ECS can beat the coherent and squeezed states as inputs in the SU(1,1)I, and the MMZI is more robust against internal photon losses than the SU(1,1)I. 相似文献
176.
177.
Ultraviolet photo-lithography is employed to introduce two-dimensional (2D) photonic crystal (PC) structure on the top surface of GaN-based light emitting diode (LED). PC patterns are transferred to 460-rimthick transparent indium tin oxide (ITO) electrode by inductively coupled plasma (ICP) etching. Light intensity of PC-LED can be enhanced by 38% comparing with the one without PC structure. Rigorous coupled wave analysis method is performed to calculate the light transmission spectrum of PC slab. Simulation results indicate that total internal reflect angle which modulated by PC structure has been increased by 7°, which means that the light extraction efficiency is enhanced outstandingly. 相似文献
178.
Deterministic quantum teleportation and information splitting via a peculiar W-class state
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In the paper ({\em Phys. Rev.} 2006 A {\bf 74} 062320)
Agrawal {\em et al}. have introduced a kind of W-class state which
can be used for the quantum teleportation of single-particle state
via a three-particle von Neumann measurement, and they thought that
the state could not be used to teleport an unknown state by making
two-particle and one-particle measurements. Here we reconsider the
features of the W-class state and the quantum teleportation process
via the W-class state. We show that, by introducing a unitary
operation, the quantum teleportation can be achieved
deterministically by making two-particle and one-particle
measurements. In addition, our protocol is extended to the process
of teleporting two-particle state and splitting information. 相似文献
179.
We propose a scheme for generating a genuine four-particle polarisation entangled state ︱χ00 that has many interesting entanglement properties and potential applications in quantum information processing. In our scheme, we use the weak cross-Kerr nonlinear interaction between field-modes and the non-demolition measurement method based on highly efficient homodyne detection, which is feasible under the current experiment conditions. 相似文献
180.
为预测企业碳排放峰值,帮助企业设计碳排放的减排路径,需要对企业碳排放峰值预测方法进行研究。当前采用基于TFDI模型的预测模型对企业碳排放峰值进行预测,预测过程中无法全面考虑企业碳排放影响因素,导致预测企业碳排放峰值出现误差。为此,提出一种基于灰色神经网络模型的企业碳排放峰值预测模型。该模型是以灰色模型为基础,与神经网络相融合构建的灰色神经网络,将模型中企业碳排放原数据进行叠加,并用微分方程表示,将VSTE算法作为灰色神经网络模型预测的基础算法,计算企业碳排放路径碳排放值,满足高斯分布随机函数,以此进行企业碳排放峰值的预测。实验结果证明,所提模型可以准确预测企业碳排放峰值,有效帮助企业设计碳排放减排路径。 相似文献