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排序方式: 共有251条查询结果,搜索用时 15 毫秒
71.
Karim Nour 《Archive for Mathematical Logic》2000,39(4):261-280
In 1990 J-L. Krivine introduced the notion of storage operators. They are -terms which simulate call-by-value in the call-by-name strategy and they can be used in order to modelize assignment instructions.
J-L. Krivine has shown that there is a very simple second order type in AF2 type system for storage operators using G?del translation of classical to intuitionistic logic. In order to modelize the
control operators, J-L. Krivine has extended the system AF2 to the classical logic. In his system the property of the unicity of integers representation is lost, but he has shown that
storage operators typable in the system AF2 can be used to find the values of classical integers. In this paper, we present a new classical type system based on a logical
system called mixed logic. We prove that in this system we can characterize, by types, the storage operators and the control
operators.
Received: 7 May 1997 相似文献
72.
We give in this paper a short semantical proof of the strong normalization for full propositional classical natural deduction.
This proof is an adaptation of reducibility candidates introduced by J.-Y. Girard and simplified to the classical case by
M. Parigot. 相似文献
73.
Let G be a connected simply connected nilpotent Lie group. In [A. Baklouti, N. Ben Salah, The Lp−Lq version of Hardy's Theorem on nilpotent Lie groups, Forum Math. 18 (2006) 245-262], we proved for 2?p,q?+∞ the Lp−Lq version of Hardy's Theorem known as the Cowling-Price Theorem. In the setup where 1?p,q?+∞, the problem is still unsolved and the upshot is known only for few cases. We prove in this paper such a result in the context of 2-NPC nilpotent Lie groups. A proof of the analogue of Beurling's Theorem is also provided in the same context. 相似文献
74.
A. Sh Ghazal M. S. M. Nour El-Din M. Y. M. Hassan 《The European Physical Journal A - Hadrons and Nuclei》2004,19(2):221-229
A linear form of density-dependent total nucleon-nucleon (NN) cross-section that depends on the coordinates of the projectile and target is applied in the Glauber phase shift formula. The only free parameter in these calculations is the density-dependent parameter
, which is adjusted to obtain an agreement between the calculated angular distribution of the elastic-scattering cross-section and the corresponding experimental one. The elastic scattering of the 12C ion on the 12C ion target has been studied at incident energies of 300, 360, 1016, 1441 and 2400 MeV. The total reaction cross-section
is also calculated with the obtained value of
for the same reactions. The obtained values of
are compared with those obtained from the optical-model analysis as well as those of the experimental value. Nuclear transparency effects are also discussed. Generally, the density-dependent NN cross-section improves the calculated results.Received: 11 February 2003, Revised: 8 July 2003, Published online: 26 January 2004PACS:
24.10.-i Nuclear-reaction models and methods - 25.70.-z Low and intermediate energy heavy-ion reactions 相似文献
75.
Mohamed G. G. Nour El-Dien F. A. El-Gamel N. E. A. 《Journal of Thermal Analysis and Calorimetry》2002,67(1):135-146
The present work aims chiefly to study the thermal behaviour of complex compounds with general formula: [M(HL)xH2O](A)yH2O (where HL=C13H11N4O2=6-(2-pyridylazo)-3-acetamidophenol (PAAP), M=Cu(II), Zn(II), Cd(II) and Fe(III) x=1, 3; y=2, 5) while A=CH3COO– (Ac), Cl2. The second formula is [M(H2L)xH2O]Cl2yH2O, (where H
2
L=C13H12N4O2 (PAAP), M=Ni(II), Co(II) x=3; y=4, 6). The compounds were identified by elemental analysis, FT-IR spectra and TG/DTG,DTA methods. It was found that during the thermal decomposition of complex compounds water molecules of crystallization are released in the first step. In the next step the pyrolysis of organic ligand takes place. Metal oxide remained as a solid product of the thermal decomposition. Mass spectroscopy has been used for the determination of the thermal decomposition on the intermediate products. It was found that the thermal stability of the studied compounds increases as the ionic radii decreases. The activation energy E, the entropy change S
*, the enthalpy H
* change and Gibbs free energy change G
* were calculated from TG curve.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
76.
The present work aims chiefly to study the thermal behaviour of Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes with 6-(2-pyridylazo)-3-acetamidophenol (PAAP) in nitrogen atmosphere. The moieties of the prepared complexes contain mainly coordinated water molecules (1-3) together with some water of crystallization. The water molecules of crystallization are removed in a single stage. The decomposition and combustion of the fragments occur in the second and subsequent stages. The fragmentation of the prepared complexes is also studied by mass spectrometry in order to identify the molecular ions obtained. The comparison of thermal analysis (TG) and mass spectra of the compounds is helpful in checking the correct proposed thermal decomposition schemes. This comparative study shows that mass spectra are correlated with the thermal analyses suggestions. The activation thermodynamic parameters of thermal decomposition pathways, such as energy of activation, enthalpy, entropy and free energy change of the complexes are evaluated and the stability of the thermal treated complexes is discussed, which shows that the thermal stabilities of the complexes are enhanced as the ionic radii decrease. 相似文献
77.
Malika Berredjem Zine Regainia Georges Dewynter Jean Louis Montero Nour‐Eddine Aouf 《Heteroatom Chemistry》2006,17(1):61-65
A series of new chiral N,N′‐sulfonyl bis‐oxazolidin‐2‐ones were synthesized starting from 2‐aminoalcohols, sulfuryl chloride, and diethyl carbonate. This method utilizes natural amino acids as a source of chirality for the preparation of oxazolidinones. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:61–65, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20183 相似文献
78.
79.
80.
This paper describes the development of screen-printed (SPE) and carbon paste (CPE) sensors for the rapid and sensitive quantification of naphazoline hydrochloride (NPZ) in pharmaceutical formulations. This work compares the electroactivity of conventional carbon paste and screen-printed carbon paste electrodes towards potentiometric titration of NPZ. The repeatability and accuracy of measurements performed in the analysis of these pharmaceutical matrices using new screen printed sensors were evaluated. The influence of the electrode composition, conditioning time of the electrode and pH of the test solution, on the electrode performance were investigated. The drug electrode showed Nernstain responses in the concentration range from 1 × 10(-6) to 1 × 10(-2) mol L(-1) with slopes of 57.5 ± 1.3 and 55.9 ± 1.6 mV per decade for SPE and CPE, respectively, and was found to be very precise and usable within the pH range 3-8. These sensors exhibited a fast response time (about 3 s for both SPE and CPE, respectively), a low detection limit (3.5 × 10(-6) and 1.5 × 10(-6) M for SPE and CPE, respectively), a long lifetime (3 and 2 months for SPE and CPE, respectively) and good stability. The selectivity of the electrode toward a large number of inorganic cations, sugars and amino acids was tested. It was applied to potentiometric determination of NPZ in pure state and pharmaceutical preparation under batch conditions. The percentage recovery values for the assay of NPZ in tablets (relative standard deviations ≤0.3% for n = 4) were compared well with those obtained by the official method. 相似文献