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51.
A new exact quantization rule simplifies the calculation of the energy levels for the exactly solvable quantum system. In this work we calculate the energy levels of the Schrödinger equation with the hyperbolic potential by this quantization rule. The corresponding eigenfunction is also derived for completeness. The second Pöschl-Teller like potential case is also carried out.  相似文献   
52.
A series of 0-D, 1-D, and 2-D metal-organic compounds through reactions of quinoline-2,3-dicarboxylic acid (2,3-H(2)qldc) with transition metal salts MCl(2), namely, M(2,3-Hqldc)(2)(H(2)O)(2) (M = Co(1), Zn(4) and Cd(7)), [M(3-qlc)(2)(H(2)O)(2)](n) (M = Co(2), Zn(5) and Cd(8)), M(2-qldc-3-OCH(3))(2)(CH(3)OH)(2) (M = Co(3) and Zn(6)) and [Cd(2,3-qldc-OCH(3))(μ(2)-Cl)](2n) (9) (where, 3-Hqlc = quinoline-3-carboxylic acid and 2-qldc-3-OCH(3) = 3-(methoxycarbonyl)quinoline-2-carboxylic acid), were synthesized and characterized by elemental analysis, IR, thermogravimetric analysis (TG), and single-crystal X-ray diffraction. When the temperature ranged from room temperature to 70 °C, three isomorphous mononuclear complexes 1, 4 and 7 were obtained in H(2)O/H(2)O + CH(3)OH. As the temperature rose further to above 90 °C, due to the decomposition of 2-position carboxyl group in ligand 2,3-H(2)qldc, the same reactions, respectively, produced three isomorphous 2-D layer-like structures 2, 5 and 8 with 4(4) topology in water. By contrast, when the mixed solvent of H(2)O + CH(3)OH at a 1?:?1 ratio (v/v) was applied, the three above-mentioned reactions respectively gave compounds 3, 6 and 9 with the 3-position esterification of 2,3-H(2)qldc. Compounds 3 and 6 are mononuclear and isomorphous, while complex 9 has a 1-D double-stranded chain-like structure connected by two μ(2)-Cl bridges. Obviously, these results reveal that the reaction temperature and solvent play a critical role in structural direction of these low-dimensional compounds. Meanwhile, the photoluminescent property of the selected compounds is also investigated.  相似文献   
53.
Non-stoichiometric Ni50Mn27 Ga23 polycrystalline ribbons are prepared by melt-spinning technique. The magneticfield-induced strain (MFIS) of Ni-Mn-Ga bulk alloy prepared by bonding the melt-spun ribbons is obtained. The experimental results show that Ni50Mn27Ga23 bonded ribbons exhibit a typical thermal-elastic shape memory effect in the thickness direction. The martensitic transformation strain of bonded ribbons is an expansive strain of about 0.3% without the magnetic field and a contractive strain of about -0.46% at the magnetic field of 1 T. The field can not only enhance the value of the martensitic transformation strain of the bonded ribbons, but can also change the direction of the strain. The bonded ribbons alloy presents negative MFIS and obtains a larger value of the strain though influenced by the adhesive between the ribbons. Therefore, the preparation technique of the Ni-Mn-Ga bulk alloy by bonding melt-spun ribbons is helpful to get rid of the size restriction of the ribbon and to broaden the applications of the ribbons.  相似文献   
54.
55.
In the paper we have constructed and investigated some properties of the Perelomov's “generalized coherent states” and photon-added coherent states for the Morse one-dimensional Hamiltonian (MO-PACSs), using the SU(2) group generators. We have found the integration measure in the resolution of unity and we have calculated some expectation values in the MO-PACSs representation. Using these states, the diagonal P-representation of the density operator is constructed as a new result for Morse potential. In addition, we have calculated some thermal expectation values for the quantum canonical diatomic gas of the Morse oscillators.  相似文献   
56.
用真空快淬炉制备了名义成分为Ni50Mn27Ga23,淬速 分别为2,4,8m/s的快淬态试样,并将部分试样热处理.研究结果表明,与铸态相比,快淬态试样马氏体相 变温度、居里温度均有所降低,经热处理后,降低的马氏体温度和居里温度会提高.快淬合 金与铸态合金相比更容易获得单相的Ni2MnGa结构,并能使合金主衍射峰从(22 0)转向( 400),形成织构,热处理后织构消失.快淬工艺对相变应变和磁致应变的影响表现出复杂性 ,研究发现获得织构的快淬带具有较浇铸态试样更大的相变应变和磁致应变. 关键词: 50Mn27Ga23')" href="#">Ni50Mn27Ga23 快淬 马氏体相变 应变  相似文献   
57.
We present the position–momentum uncertainties for the Pöschl–Teller potential. We observe that the Δx decreases with the potential depth λ but increases with quantum number n. Interestingly, we find that the Δp first increases and then decreases with the n  . The ΔxΔpΔxΔp first decreases and then increases with the λ  , but almost becomes a constant (n+1/2)?(n+1/2)? for a larger λ. Particularly, there exists a squeezed phenomenon in position x for the lower states. The squeezing in x compensated for by an increase in momentum p  , such that ΔxΔp??/2ΔxΔp??/2 is still satisfied.  相似文献   
58.
杨世海  金克新  王晶  罗炳成  陈长乐 《物理学报》2013,62(14):147305-147305
利用脉冲激光沉积法成功制备了BaTiO3/p-Si异质结, 该异质结在80–300 K 显示出了良好的整流特性和光诱导特性. 开启电压随着温度的升高而逐渐降低. 利用不同频率的光子辐照样品, 观察到明显的光电导效应. 且随着照射光子能量的增大, 结电流也相应变大, 光诱导效应越明显. BaTiO3薄膜电阻-温度(R-T) 曲线显示氧缺陷条件下BaTiO3薄膜具有良好的半导体特性. 关键词: 异质结 光诱导效应 3薄膜')" href="#">BaTiO3薄膜  相似文献   
59.
This work illustrates a possible application of quantum game theory to the area of quantum information, in particular to quantum cryptography. The study proposed two quantum key-distribution (QKD) protocols based on the quantum version of the Monty Hall game devised by Flitney and Abbott. Unlike most QKD protocols, in which the bits from which the key is going to be extracted are encoded in a basis choice (as in BB84), these are encoded in an operation choice. The first proposed protocol uses qutrits to describe the state of the system and the same game operators proposed by Flitney and Abbott. The motivation behind the second proposal is to simplify a possible physical implementation by adapting the formalism of the qutrit protocol to use qubits and simple logical quantum gates. In both protocols, the security relies on the violation of a Bell-type inequality, for two qutrits and for six qubits in each case. Results show a higher ratio of violation than the E91 protocol.  相似文献   
60.
Based on a Hamiltonian identity,we study one-dimensional generalized hypervirial theorem,Blanchardlike(non-diagonal case) and Kramers'(diagonal case) recurrence relations for arbitrary x~κ which is independent of the central potential V(x).Some significant results in diagonal case are obtained for special κ in x~κ(κ≥ 2).In particular,we find the orthogonal relation(n_1|n_2) = δ_(n_1n_2)(κ = 0),(n_1|V'(x)\n_2) =(E_(n_1)-E_(n_2))~2〈n_1x|n_2)(κ = 1),E_n =(n/V'(x)x/2|n) +(n|V(x)|n)(κ = 2) and-4E_n(n|x|n) +(n|V'(x)x~2\n〉 +4〈n|V(x)x|n〉 = 0(κ = 3).The latter two formulas can be used directly to calculate the energy levels.We present useful explicit relations for some well known physical potentials without requiring the energy spectra of quantum system.  相似文献   
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