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91.
The multi-particle states and rotational properties of the two-particle bands in 254No are investigated by the cranked shell model with pairing correlations treated by the particle number conserving method.The rotational bands on top of the two-particle K^π=3^+,8^− and 10^+ states and the pairing reduction are studied theoretically in 254No for the first time.The experimental excitation energies and moments of inertia of the multi-particle states are reproduced well by the calculations.Better agreement with the data is achieved by including the high-order deformation ε6,which leads to enlarged Z=100 and N=152 deformed shell gaps.An increase of J1 in these two-particle bands compared with the ground state band is attributed to the pairing reduction due to the Pauli blocking effect. 相似文献
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Designing and preparing air-stable high-performance single-molecule magnets (SMMs) is of great significance toward the implementation of SMMs in high-density information storage,quantum computation and molecular-based spintronics devices. Herein,an air-stable macrocyclic Dy (III) single-ion magnet with pentagonal bipyramidal local symmetry is obtained by the reaction between N,N'-bis (2-aminoethyl)-1,3-propanediamine and 2,6-diacetylpyridine with the dysprosium ion as template. Single crystal X-ray diffraction reveals that the dysprosium ion is encapsulated in the equatorial plane with BPh4− as counter anion and the axial position is occupied by two Ph3 SiO−. The state magnetic measurements gives the χM T value of 13. 96 cm3·K/mol at room temperature,close to the theoretical value of 14. 17 cm3·K/mol for one isolated Dy (III) ion. The dynamic magnetic measurements confirm its typical SMM behavior under a zero dc field with the effective magnetic reversal barrier up to 1008 K. Magneto-structural investigations show that the excellent SMM properties are attributed to the D5h local symmetry and the strongly axial crystal field created by two Ph3 SiO− for the dysprosium ion. Thermogravimetric analysis indicates that the compound is extremely air stable and the decomposition temperature reaches up to 297 ℃ ,which provides a promising avenue for depositing high performance SMMs on conductive substrate surfaces. © 2022, Science Press (China). All rights reserved. 相似文献
96.
以氮杂环化合物为电化学分析底物的2-氨基-3-羟基吡啶-H2O2-辣根过氧化物酶(HRP)伏安酶联免疫体系测定人血清癌胚抗原(CEA).HRP催化H2O2氧化2-氨基-3-羟基吡啶的酶促反应产物,在缓冲液中-0.36 V处产生一个灵敏的伏安还原峰,借助此峰可以测定游离的HRP,进而可用于以HRP为标记物的酶联免疫分析.对酶促反应条件和测定条件的优化反应条件为:以B-R缓冲液(pH 6.0)为反应介质,在10 mL总反应液中含有1.0 mL 0.2 mol/L B-R缓冲液、3.0 mL 8.0 mmol/L 2-氨基-3-羟基吡啶溶液以及1.5 mL 0.5 mmol/L H2O2溶液,反应温度37 ℃,反应时间30 min.最佳测定条件为:B-R缓冲液(pH 7.0)为支持电解质,在10 mL总测定溶液中含有5 mL上述总反应液、1.0 mL 0.2 mol/L B-R缓冲液.测定仪器条件:起始电位0.00 V,终止电位-0.80 V,电位扫描速度400 mV/s,滴汞静止时间7 s.在最佳的反应条件和测定条件下,新体系测定游离HRP的线性范围为4.0×10-4~1.0 μg/L; 对HRP的检出限为0.12 ng/L.新体系对CEA测定的线性范围为0.50~80.0 μg/L; 检出限为0.50 μg/L.为经典ELISA法的检出限的1/10. 相似文献
97.
采用溶胶-凝胶(sol-gel)工艺制备0.1 mol% Er3+掺杂Al2O3体系和SiO2-Al2O3复合体系粉末. 实验结果表明:5 mol%的SiO2复合加入Al2O3抑制γ→θ和θ→α相转变. 掺0.1 mol%Er3+:Al2O3体系粉末,900℃烧结,在1.47-1.63 μm波段内光致发光(PL)谱为中心波长1.53 μm、半高宽56 nm的单一宽峰,1000-1200℃烧结,劈裂为多峰PL谱. 掺0.1 mol%Er3+:SiO2-Al2O3复合体系粉末,在高达1200℃烧结,仍保持中心波长1.53 μm的单一宽峰PL谱,由于-OH更完全的脱除,PL强度较900℃烧结Al2O3体系,SiO2-Al2O3复合体系均提高1个数量级. 相似文献
98.
Study of a rectangular coupled cavity extendedinteraction oscillator in sub-terahertz waves
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An extended interaction oscillator (EIO) generating 120 GHz wave in sub-terahertz waves is studied by using the three-dimensional electromagnetic simulation software CST and PIC codes. A rectangular reentrant coupled-cavity is proposed as the slow-wave structure of EIO. By CST, the circuit parameters including frequency-phase dispersion, interaction impedance and characteristic impedance are simulated and calculated. The operation mode of EIO is chosen very close to the point where βL = 2π with corresponding frequency 120 GHz, the beam voltage 12 kV and the dimensions of the cavity with the period 0.5mm, the height 3mm and the width 1.4mm. Simulation results of beam-wave interaction by PIC show that the exciting frequency is 120.85 GHz and output peak power 465 W with 12-period coupled-cavity with the perveance 0.17 μP. Simulation results indicate that the EIO has very wide range of the operation voltage. 相似文献
99.
The crystal structure of the minor phase, named superstructure II, existing in multiferroic compound BiMnO3 has been studied by electron diffraction and high-resolution transmission electron microscopy. Domains of major and minor phases coexisting in BiMnO3 were observed in high-resolution electron microscope images. The unit cell of minor phase was determined to be triclinic with the size 4×4×4 times as large as the distorted perovskite subcell. The [111] and [101] projected structure maps of the minor phase have been derived from the corresponding images by means of the image processing. A possible rough three-dimensional (3D) structure model was proposed based on the 3D structural information extracted from the two projected structure maps. Since there is no inversion centre in the proposed model, the minor phase may contribute to the ferroelectric property of BiMnO3. 相似文献
100.
FUZun-Tao YAOZhen-Hua LIUShi-Kuo LIUShi-Da 《理论物理通讯》2005,44(1):23-30
In this paper, four transformations are introduced to solve single sine-Gordon equation by using the knowledge of elliptic equation and Jacobian elliptic functions. It is shown that different transformations are required in order to obtain more kinds of solutions to the single sine-Gordon equation. 相似文献