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The entry distribution in angular momentum and excitation energy for the formation of 254No has been measured after the 208Pb(48Ca,2n) reaction at 215 and 219 MeV. This nucleus is populated up to spin 22Planck's over 2pi and excitation energy greater, similar6 MeV above the yrast line, with the half-maximum points of the energy distributions at approximately 5 MeV for spins between 12Planck's over 2pi and 22Planck's over 2pi. This suggests that the fission barrier is greater, similar5 MeV and that the shell-correction energy persists to high spin.  相似文献   
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Let E/Q be an elliptic curve with complex multiplication by the ring of integers of an imaginary quadratic field K. In 1991, by studying a certain special value of the Katz two-variable p-adic L-function lying outside the range of p-adic interpolation, K. Rubin formulated a p-adic variant of the Birch and Swinnerton–Dyer conjecture when E(K) is infinite, and he proved that his conjecture is true for E(K) of rank one. When E(K) is finite, however, the statement of Rubin’s original conjecture no longer applies, and the relevant special value of the appropriate p-adic L-function is equal to zero. In this paper we extend our earlier work and give an unconditional proof of an analogue of Rubin’s conjecture when E(K) is finite.  相似文献   
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Team sport competition can be characterized as a complex adaptive system in which concepts from nonlinear dynamics can provide a sound theoretical framework to understand emergent behavior such as movement coordination and decision making in game play. Nonlinear Pedagogy is presented as a methodology for games teaching, capturing how phenomena such as movement variability, self-organization, emergent decision making, and symmetry-breaking occur as a consequence of interactions between agent-agent and agent-environment constraints. Empirical data from studies of basketball free-throw shooting and dribbling are used as task vehicles to exemplify how nonlinear phenomena characterize game play in sport. In this paper we survey the implications of these data for Nonlinear Pedagogy, focusing particularly on the manipulation of constraints in team game settings. The data and theoretical modeling presented in this paper provide a rationale in nonlinear dynamics for the efficacy of a prominent model of game play teaching, Teaching Games for Understanding approach.  相似文献   
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Electrocatalysis of epinephrine at gold electrode pre‐modified with the self‐assembled monolayer of cysteamine and subsequently integrated with novel metallo‐octacarboxyphthalocyanine (MOCPc where M=Fe, Co and Mn) complexes (Au‐Cys‐MOCPc) was investigated. The electrodes showed response to the presence of epinephrine. The oxidation peak potential (Ep/V vs. Ag|AgCl, sat'd KCl) and charge transfer resistance (Rct (kΩ)) in epinephrine solution depend markedly on the central metal of the phthalocyanine cores: Au‐Cys‐FeOCPckch=4.1×107 M?1 s?1) which is higher than that of the Au‐cys‐CoOCPc or Au‐cys‐MnOCPc electrode. Mechanism, recognizing the mediation of the electrocatalytic process by the central M(II)/M(III) redox processes was proposed. Epinephrine electro‐oxidation at the Au‐cys‐FeOCPc electrode was studied in more details for the response characteristics. The diffusion coefficient of epinephrine was evaluated as (2.62±0.23)×10?9 cm2 s?1. It was established that Au‐Cys‐FeOCPc is suitable for sensitive determination of epinephrine in physiological pH (7.40) conditions showing linear concentration range of up to 300 nM, with excellent sensitivity (0.53±0.01 nA nM?1), and very low limits of detection (13.8 nM) and quantification (45.8 nM). The peak separation between ascorbic acid and epinephrine is large enough (190 mV) to permit simultaneous determination of both epinephrine and ascorbic acid in physiological pH 7.4 conditions using the Au‐cys‐FeOCPc electrode. Au‐cys‐FeOCPc electrode was successfully used for the determination of epinephrine in epinephrine hydrochloric acid injection with recovery of ca. 98.4%.  相似文献   
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Nitrogen isotope ratio of nitrate provides a powerful tool to investigate nitrate sources and cycling mechanisms. Although the use of an isotope ratio method for 15N/14N allows identifying the nitrate sources in rivers by estimating a seasonal variation of N-NO3 concentration, however, there are some restrictions. Nitrification, the conversion of NH4+ to NO3-, can proceed with significant nitrogen isotope fractionation, preferentially accumulating 14N in the produced NO3-, and can make it difficult to identify the nitrate source with a high proportion of the isotope δ15N. However, the uptake and assimilation of NH4+ and NO3- have the capability of affecting isotopic compositions of riverine nitrogen compounds, and this may hinder the determination of whether the impact of the nitrate source with a high proportion of the isotope δ15N reduces. In addition, this study demonstrates that nitrate nitrogen concentration may correlate with δ15NNO3 values both positively and negatively. Such correlations are the result of isotope effects during nitrogen transformation processes (e.g. nitrification and assimilation) and isotopic variability in the various nitrate sources. A comparison of NO3- concentration and δ15NNO3 can be used to further distinguish mixing from biological processing. However, in order to get a more precise answer regarding the nitrate sources, it would be useful to take both the data of nitrogen isotopes and data of oxygen isotopes present in nitrates.  相似文献   
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