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71.
Aminobisphosphonates, e.g., alendronate and neridronate, are a well known class of molecules used as drugs for various bone diseases. Although these molecules have been available for decades, a detailed understanding of their most important physicochemical properties under comparable conditions is lacking. In this study, ten aminobisphosphonates, H2N(CH2)nC(OH)[P(O)(OH)2]2, in which n = 2-5, 7-11 and 15 have been synthesized. Their aqueous solubility as a function of temperature and pH, pKa-values, thermal stability, IR absorptions, and NMR spectral data for bothliquid (1H, 13C, 31P-NMR) and solid state (13C, 15N and 31P-CPMAS NMR) were determined.  相似文献   
72.
Using Singh-Rajput MES as memory states in the evolutionary process of pattern storage and the non-evolutionary process of pattern recall (the two fundamental constituents of QuAM), the suitability and superiority of these MES over Bell’s MES have been demonstrated in both these processes. It has been shown that, under the operations of all the possible memorization operators for a two-qubit system, the first two states of Singh-Rajput MES are useful for storing the pattern |11> and the last two of these MES are useful in storing the pattern |10> while Bell’s MES are not much suitable as memory states in a valid memorization process. The recall operations have also been conducted by separately choosing Singh-Rajput MES and Bell’s MES as memory states for possible various queries and it has been shown that in each case the choices of Singh-Rajput MES as valid memory states are much more suitable than those of Bell’s MES.  相似文献   
73.
Eight Janus-type dendrimers up to the second generation were synthesized, and their thermal properties were evaluated. Compounds consist of the dendritic bisMPA based polyester moieties, and either 3,4-dihexyloxybenzoic acid or 3,4-dihexadecyloxybenzoic acid moieties, attached to opposite sides of the pentaerythritol core. The structures of the molecules were verified with 1H NMR, 13C NMR, ESI TOF mass spectrometry and elemental analysis. The thermal stability was evaluated by thermogravimetric analysis, displaying onset decomposition temperatures (Td) ranging from 241 to 308 °C. Phase transitions were studied by differential scanning calorimetry. Based on the performed studies it was confirmed that OH terminated dendrimers 2, 4, 6 and 8 exhibited liquid crystalline phases. Also, the X-ray powder diffraction measurements were accomplished for the dendrimers having terminal hydroxyl groups.  相似文献   
74.
Carrying out the classification of patterns in a two-qubit system by separately using Grover’s and Ventura’s algorithms on different possible superposition, it has been shown that the exclusion superposition and the phase-invariance superposition are the most suitable search states obtained from two-pattern start-states and one-pattern start-states, respectively, for the simultaneous classifications of patterns. The higher effectiveness of Grover’s algorithm for large search states has been verified but the higher effectiveness of Ventura’s algorithm for smaller data base has been contradicted in two-qubit systems and it has been demonstrated that the unknown patterns (not present in the concerned data-base) are classified more efficiently than the known ones (present in the data-base) in both the algorithms. It has also been demonstrated that different states of Singh-Rajput MES obtained from the corresponding self-single- pattern start states are the most suitable search states for the classification of patterns |00>,|01 >, |10> and |11> respectively on the second iteration of Grover’s method or the first operation of Ventura’s algorithm.  相似文献   
75.
76.
We report a simulation of deuterated water using a Car-Parrinello approach based on maximally localized Wannier functions. This provides local information on the dynamics of the hydrogen-bond network and on the origin of the low-frequency infrared activity. The oscillator strength of the translational modes, peaked around approximately 200 cm-1, is anisotropic and originates from intermolecular--not intramolecular--charge fluctuations. These fluctuations are a signature of a tetrahedral hydrogen-bonding environment.  相似文献   
77.
Samples of high alloy Stainless Steel SS 1 were analyzed by instrumental neutron activation analysis (INAA) at 5 research institutes in 4 European countries within the frame of an Inter-Laboratory Comparison (ILC) exercise aiming at checking if the results were independent of the standardization methods, and if INAA was accurate enough to contribute to certification. The mean element concentration values yielded by INAA were also compared with mean values obtained by atomic emission spectroscopy techniques at other laboratories that took part in the International Proficiency Testing organized by KIMAB Institute of Sweden, producer of the SS 1. The performances of the nuclear and atomic techniques were compared in terms of the z-score values calculated for 11 element concentrations evaluated by the two analytical ways. Finally, consideration is given to the ways in which highest accuracy and precision can be ensured for certifying stainless steels as CRMs.  相似文献   
78.
Realization of qudit quantum computation has been presented in terms of number operator and phase operators associated with one-dimensional harmonic oscillator and it has been demonstrated that the representations of generalized Pauli group, viewed in harmonic oscillator operators, allow the qudits to be explicitly encoded in such systems. The non-Hermitian quantum phase operators contained in decomposition of the annihilation and creation operators associated with harmonic oscillator have been analysed in terms of semi unitary transformations (SUT) and it has been shown that the non-vanishing analytic index for harmonic oscillator leads to an alternative class of quantum anomalies. Choosing unitary transformation and the Hermitian phase operator free from quantum anomalies, the truncated annihilation and creation operators have been obtained for harmonic oscillator and it has been demonstrated that any attempt of removal of quantum anomalies leads to absence of minimum uncertainty.  相似文献   
79.
The design of molecular containers capable of selectively binding specific guest molecules presents an interesting synthetic challenge in supramolecular chemistry. Here, we report the synthesis and structure of a coordination cage assembled from Cu3I4 clusters and tripodal cationic N-donor ligands. Owing to the localized permanent charges in the ligand core the cage binds iodide anions in specific regions within the cage through ionic interactions. This allows the selective binding of bromomethanes as secondary guest species within the cage promoted by halogen bonding, which was confirmed by single-crystal X-ray diffraction.  相似文献   
80.
In the present paper, simultaneous classification of Orange and Apple has been carried out using both Grover’s iterative algorithm (Grover 1996) and Ventura’s model (Ventura and Martinez, Inf. Sci. 124, 273–296, 2000) taking different superposition of two- pattern start state containing Orange and Apple both, one- pattern start state containing Apple as search state and another one- pattern start state containing Orange as search state. It has been shown that the exclusion superposition is the most suitable two- pattern search state for simultaneous classification of pattern associated with Apples and Oranges and the superposition of phase-invariance are the best choice as the respective search state based on one –pattern start-states in both Grover’s and Ventura’s methods of classifications of patterns.  相似文献   
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