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1.
Mohamed El Guendouzi Abderrahim Dinane Abdelfetah Mounir 《Journal of solution chemistry》2002,31(2):119-129
The mixed aqueous electrolyte system of ammonium and lithium chlorides has been studied by the hygrometric method at 25°C. The relative humidities of this system are measured at total molalities from 0.3 to 6 mol-kg– 1 for different ionic-strength fractions y of NH4Cl with y = 0.33, 0.50, and 0.67. The data obtained allow the deduction of new water activities and osmotic coefficients. The experimental results are compared with the predictions of the ECA (extended composed additivity) law proposed in our previous work. The Zdanovskii–Stokes–Robinson (ZSR), the Robinson–Stokes (RS), Reilly–Wood–Robinson (RWR), the Pitzer, and the Lietzke–Stoughton (LS II) models are also compared with our results. Predictions made using these models are, in general, consistent with our results. From these measurements, new Pitzer mixing ionic parameters are determined and used to predict the solute activity coefficients in the mixture for different ionic-strength fractions. 相似文献
2.
Abdelfetah Mounir Mohamed El Guendouzi Abderrahim Dinane 《Journal of solution chemistry》2002,31(10):793-799
Ternary aqueous solutions of MgSO4 and K2SO4 have been studied by the hygrometric method at 25°C. The relative humidity of this system is measured at total molalities from 0.35 mol-kg–1 to about saturation for three ionic-strength fractions (y = 0.25, 0.50, and 0.80 of MgSO4. The data allow calculation of water activities and osmotic coefficients. From these measurements, the Pitzer ionic mixing parameters are determined and used to predict the solute activity coefficients in the mixture. The results are used to calculate the excess Gibbs energy at total molalities for ionic-strength fraction y. 相似文献
3.
Ahmed Fouzi Tarchoun Djalal Trache Amir Abdelaziz Abdelatif Harrat Walid Oussama Boukecha Mohamed Abderrahim Hamouche Hani Boukeciat Mohammed Dourari 《Molecules (Basel, Switzerland)》2022,27(20)
This research aims to develop new high-energy dense ordinary- and nano-energetic composites based on hydrazine 3-nitro-1,2,4-triazol-5-one (HNTO) and nitrated cellulose and nanostructured nitrocellulose (NC and NMCC). The elaborated energetic formulations (HNTO/NC and HNTO/NMCC) were fully characterized in terms of their chemical compatibility, morphology, thermal stability, and energetic performance. The experimental findings implied that the designed HNTO/NC and HNTO/NMCC formulations have good compatibilities with attractive characteristics such as density greater than 1.780 g/cm3 and impact sensitivity around 6 J. Furthermore, theoretical performance calculations (EXPLO5 V6.04) displayed that the optimal composition of the as-prepared energetic composites yielded excellent specific impulses and detonation velocities, which increased from 205.7 s and 7908 m/s for HNTO/NC to 209.6 s and 8064 m/s for HNTO/NMCC. Moreover, deep insight on the multi-step kinetic behaviors of the as-prepared formulations was provided based on the measured DSC data combined with isoconversional kinetic methods. It is revealed that both energetic composites undergo three consecutive exothermic events with satisfactory activation energies in the range of 139–166 kJ/mol for HNTO/NC and 119–134 kJ/mol for HNTO/NMCC. Overall, this research displayed that the new developed nanoenergetic composite based on nitrated cellulose nanostructure could serve as a promising candidate for practical applications in solid rocket propellants and composite explosives. 相似文献
4.
Wakif Abderrahim Chamkha Ali Thumma Thirupathi Animasaun I. L. Sehaqui Rachid 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1201-1220
Journal of Thermal Analysis and Calorimetry - Sequel to the fact that hybrid nanofluidic systems (e.g. scalable micro-/nanofluidic device) exhibit greater thermal resistance with increasing... 相似文献
5.
Raoudha Abderrahim Belgacem Baccar et Mohamed Lamine Benkhoud 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1033-1040
The reaction of hexamethylphosphotriamide or methylphosphonic bis(dimethylamide) compounds with amidines derived from N-Benzimidazoyl imidates 1 leads to (1,2a)benzimidazolo-1,3,5,2-tiazaphosphorine-2-oxides 4 in good yields. If the condensation is realized at room temperature, N-phosphonic amidines 3 can be isolated as intermediates. The isolated compounds 2 , 3 , and 4 are identified by spectroscopic methods: IR, 1 H, 13 C, 31 P, NMR, and M.S. 相似文献
6.
Begaa Samir Messaoudi Mohammed Ouanezar Abdelkader Hamidatou Lylia Malki Abderrahim 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(2):1107-1112
Journal of Radioanalytical and Nuclear Chemistry - The objectives of this research were to study the elemental concentrations of Mentha spicata L., using a sensitive nuclear analytical technique... 相似文献
7.
Reaction of ethyl chloroformate and acyl chlorides with iminoesters derived from 2- aminobenzimidazole, followed by Grignard reagent condensation leads to a variety of oxadiazinobenzimidazoles in good yield. 相似文献
8.
M. Smadhi R. Abderrahim 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2229-2232
The condensation of hexamethylphosphorotriamide and bis-(dimethylamino) methylphosphonate with amidrazones 1 constitutes a new route to the synthesis of 1,2,4,3-triazaphosphole-3-oxide derivatives 3. Structures of all the synthesized compounds have been established by NMR (1H, 13C, 31P) and IR spectroscopy, as well as by elemental analysis and MS spectral data for some products. 相似文献
9.
Tanguy Jousselin-Oba Masashi Mamada Karen Wright Jrome Marrot Chihaya Adachi Abderrahim Yassar Michel Frigoli 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2022,134(1):e202112794
We report the synthesis and optoelectronic properties of TIPS-peri-pentacenopentacene ( TIPS-PPP ), a vertical extension of TIPS-pentacene ( TIPS-PEN ) and a low-band-gap material with remarkable stability. We found the synthetic conditions to avoid the competition between 1,2- and 1,4-addition of lithium acetylide on the large aromatic dione. The high stability of TIPS-PPP is due to the peri-fusion which increases the aromaticity by generating two localized aromatic sextets that are flanked with 2 diene fragments, similar to two fused-anthracenes. Like TIPS-PEN , TIPS-PPP shows the archetypal 2D brickwall motif in crystals with a larger transfer integral and smaller reorganization energy. The high mobility of up to 1 cm2 V?1 s?1 was obtained in an organic field-effect transistor fabricated by a wet process. Also, TIPS-PPP was used as a near-infrared (NIR) emitter for NIR organic-light-emitting-diode devices resulting in a high external quantum efficiency at 800 nm. 相似文献
10.
Abderrahim A?t Adoubel Christophe J. Morin Nadine Mofaddel Georges Dupas Paul-Louis Desbène 《Analytical and bioanalytical chemistry》2009,394(2):597-608
Enantiomer separations of underivatised amino acids were carried out by using ligand exchange capillary electrophoresis (LECE).
Chiral discrimination is based on the formation of ternary complexes between copper(II), a chiral selector (L-proline or trans-4-hydroxy-L-proline) and an amino acid. All amino acids containing aromatic moieties or not were detected at 214 nm because
of their interactions with copper(II). In order to reduce copper(II) adsorption onto capillary walls, we used hexadimethrine
bromide to reverse the electroosmotic flow. Using this original strategy, the studied enantiomers migrated in the opposite
direction of the anodic electroosmosis. After optimising the analytical conditions taking into account the chiral resolution
and the detection sensitivity, we performed very satisfactory enantioseparations not only of aromatic amino acids (tryptophan,
tyrosine, phenylalanine and histidine) but also of aliphatic amino acids (threonine, serine, isoleucine and valine). These
enantioseparations were performed in a short analysis time at 35 °C. In order to rationalise the obtained results, we evaluated
the complexation constants corresponding to the formed ternary complexes by capillary electrophoresis and we used molecular
mechanics modelling. 相似文献