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81.
Dynamical effects on the single-particle self-energy Σm(ω), i.e., its ω dependence, are studied microscopically using realistic finite-range NN interactions. In heavy nuclei the coupling of particles to high collective low-lying surface vibrations causes dynamical effects much stronger than in nuclear matter. This result can resolve the discrepancies in previous calculations of giant dipole resonance energies. 相似文献
82.
83.
G. WEIRAUCH M. I. EL IDRISSI J. VANDER AUWERA M. HERMAN A. CAMPARGUE 《Molecular physics》2013,111(11):969-980
The absorption spectrum of dideuteroacetylene has been recorded by intracavity laser absorption spectroscopy (ICLAS) in the 10 200–12 500cm?1 spectral region. Among 25 absorption bands of 12C2D2 rotationally analysed in this spectral region, 17 are newly observed. They include one IIu-Σ+ g and thirteen Σ+ u-Σ+ g bands starting from the vibrational ground state and eleven hot bands from the V 4 = 1 and V 5 = 1 lower states. The rotational structure of two excited levels is affected by a strongly J-dependent interaction with a perturber which induces intensity transfer to extra lines. The coupling is identified as a I-resonance interaction with δu dark states and the vibrational assignment of the perturbers is discussed. Two Σ-Σ bands of the 12C13 CD2 species, present in natural abundance in the sample, could also be identified and rotationally analysed. Most of the corresponding excited vibrational levels of 12C2D2 were unambiguously assigned using the polyad model [Herman, M., el idrissi, M. I., Pisarchik, A., Campargue, A., Gaillot, A.-C., Biennier, L., di lonardo, G. and Fusina, L., 1998, J. chem. Phys., 108, 1377] which allows vibrational energies and B V rotational constants to be predicted. In particular the previously highlighted 1/244 anharmonic resonance is confirmed by energy and intensity features in several {(V 1, V 2, V 3, V 4 = 0, V 5 = 0),(V 1 ?1, V 2 + 1, V 3 V 4 = 2, V 5 = 0)} dyads. Significant deviations between predicted and experimental energy levels are observed for a few levels and discussed. 相似文献
84.
Acta Mathematica Hungarica - For a real biquadratic field, we denote by $$\lambda$$ , $$\mu$$ and $$\nu$$ the Iwasawa invariants of cyclotomic $$\mathbb{Z}_{2}$$ -extension of $$k$$ . We give... 相似文献
85.
Nor EL Houda Tahiri Hamza Saghrouchni Noureddine Hamamouch Mostafa El Khomsi Abdulhakeem Alzahrani Ahmad Mohammad Salamatullah Lyoussi Badiaa Lalla Aicha Lrhorfi 《Molecules (Basel, Switzerland)》2022,27(23)
During the postharvest period, citrus fruits are exposed to Penicillium italicum, Penicillium digitatum, and Geotrichum candidum. Pesticides such as imazalil (IMZ), thiabendazole (TBZ), orthophenylphenol (OPP), and guazatine (GUA) are commonly used as antifungals. Glyphosate (GP) is also used in citrus fields to eliminate weed growth. The sensitivity of fungal pathogens of citrus fruit to these pesticides and 1,8-cineole was evaluated, and the effect of GP on the development of cross-resistance to other chemicals was monitored over a period of 3 weeks. IMZ most effectively inhibited the mycelial growth and spore germination of P. digitatum and P. italicum, with minimum inhibitory concentrations (MICs) of 0.01 and 0.05 mg/mL, respectively, followed by 1,8-cineole, GP, and TBZ. 1,8-Cineole and GP more effectively inhibited the mycelial growth and spore germination of G. candidum, with minimum inhibitory concentrations (MICs) of 0.2 and 1.0 mg/mL, respectively, than OPP or GUA. For the spore germination assay, all substances tested showed a total inhibitory effect. Subculturing the fungal strains in culture media containing increasing concentrations of GP induced fungal tolerance to GP as well as to the fungicides. In soil, experiments confirmed that GP induced the tolerance of P. digitatum to TBZ and GP and the tolerance of P. italicum to IMZ, TBZ, and GP. However, no tolerance was recorded against 1,8-cineole. In conclusion, it can be said that 1,8-cineole may be recommended as an alternative to conventional fungicides. In addition, these results indicate that caution should be taken when using GP in citrus fields. 相似文献
86.
André L. Boehman Jon Luecke Lisa Fouts Matthew Ratcliff Bradley T Zigler Robert L. McCormick 《Proceedings of the Combustion Institute》2021,38(4):5549-5555
This study explores the impacts of combinations of biofuel (ethanol, isobutanol and 2-methyl furan) and aromatic (toluene) compounds in a four component fuel blend, at fixed research octane number (RON) on ignition delay measured in an advanced fuel ignition delay analyzer (AFIDA 2805). Ignition delay measurements were performed over a range of temperatures from 400 to 725 °C (673 to 998 K) and two chamber pressures of 10 and 20 bar. The four component mixtures are compared to primary reference fuels at RON values of 90 and 100. The ignition delay measurements show that as the aromatic and biofuel concentrations increased, two stage ignition behavior was suppressed, at both initial chamber pressures. But both RON 100 (isooctane) and RON 90 reference fuels showed two stage ignition behavior, as did fuel mixtures with low biofuel and aromatic content. RON 90 fuels showed stronger two stage ignition behavior than RON 100 fuels, as expected. Depending on the type of biofuel in the mixture, the ignition delay at low chamber temperatures could be far greater than for the reference fuels. In particular, for the RON 100 mixtures at either 10 or 20 bar initial chamber pressure, the ignition delay at 400 °C (673 K) for the high level blend of 2-methyl furan and toluene (30 vol% of each) exhibited an ignition delay that was 10 times longer than for neat isooctane. The results show the strong non-linear octane blending response of these three biofuel compounds, especially in concert with the kinetic antagonism that toluene is known to display in mixtures with isooctane. These results have implications for the formulation of biofuel mixtures for spark ignition and advanced compression ignition engines, where this non-linear octane blending response could be exploited to improve knock resistance, or modulate the autoignition process. 相似文献
87.
MANSOURI Said MAJDOUBI Hicham HADDAJI Younesse TAMRAOUI Youssef EL ACHABY Mounir MANOUN Bouchaib ABOURRICHE Abdelkrim HANNACHE Hassan OUMAM Mina 《高等学校化学研究》2020,36(6):1339-1347
This paper discusses the elaboration of adsorbents from oil shale. The experimental designs a response surface methodology(RSM), which has been applied to optimize the significant preparation factors, such as temperature, time, and the activating agent percentage. The results obtained from central composite design(CCD) revealed that the interaction between the factors was significant for the maximum quantity of adsorption(response). Planned results have shown that a maximum quantity of adsorption for methylene blue is 65 mg/g, which could be achieved with a temperature of 275℃ over 2 h and a percentage of the activating agent of 45%. The predicted values agreed with the experimental finding, with a determination coefficient(R2) of 0.96. The model has been validated by experiments after conditions optimization. The new material(RHO) was characterized by cation exchange capacity, zero charge pH, surface functions, X-ray fluorescence, specific surface area, and electron microscopy analysis. Phenol adsorption was determined using Langmuir, Freundlich and Temkin, which were used to describe the adsorption isotherms. The adsorption capacity of the material was about 263 mg/g, and the kinetic studies showed rapid adsorption. 相似文献
88.
Aboufaris EL Alaoui S. M. Ghallali L. EL Guendouzi M. Benbiyi A. 《Journal of solution chemistry》2022,51(7):802-815
Journal of Solution Chemistry - In this investigation, calculated and experimental solubilities of the binary aqueous solutions of dipotassium hydrogenphosphate and disodium hydrogenphosphate have... 相似文献
89.
Let K be a compact Lie group acting on a finite dimensional Hermitian vector space V via some unitary representation. Now K acts by automorphisms on the associated Heisenberg group ${H_V=V \times \mathbb{R}}$ , and we say that (K, H V ) is a Gelfand pair when the algebra ${L^1_K(H_V)}$ of integrable K-invariant functions on H V commutes under convolution. In this situation an application of the Orbit Method yields a injective mapping ${\Psi}$ from the space Δ(K, H V ) of bounded K-spherical functions on H V to the space ${\mathfrak{h}_V^{*}/K}$ of K-orbits in the dual of the Lie algebra for H V . We prove that ${\Psi}$ is a homeomorphism onto its image provided that the action of K on V is “well-behaved” in a sense made precise in this work. Our result encompasses a widely studied class of examples arising in connection with Hermitian symmetric spaces. 相似文献
90.
Haddou EL Ghazi Anouar Jorio Izeddine Zorkani Mohamed Ouazzani-Jamil 《Optics Communications》2008,281(12):3314-3319
Electroluminescence (EL) properties of InxGa1−xN/AlyGa1−yN/GaN/SiC diode were studied. The spectral range for which EL spectra were recorded is 1–3.5 eV. Room temperature EL was obtained for forward bias (3.18 V, 220 μA) at 446.067 nm (blue luminescence band), 606.98 nm (yellow luminescence band) and 893.84 nm (Infrared luminescence band). The EL temperature dependence shows that, BL band is mostly given by e–h recombination corresponding to indium composition equal to 0.17 ± 0.01 and 0.14 ± 0.02 obtained theoretically and experimentally, respectively. The yellow band is generally weak and absent at low temperature. The IRL band is more consistent with the DAP recombination and could be explained by the thermal activation of Mg states. The luminescence bands shift to lower energies is due probably to the larger potential fluctuations effect. 相似文献