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281.
N. Khalifa B. Yacoubi I. Attar A. Bardaoui R. Chtourou 《Colloid and polymer science》2013,291(11):2705-2709
In this work, we study the inclusion mechanism of Fe3+ ions in a polyvinyl alcohol (PVA) matrix. Thin films of pure and FeCl3-doped PVA on silicon substrates, prepared by the spin-coating method, are investigated using spectroscopic ellipsometry (SE) and Fourier transform infrared (FT-IR) spectroscopy. SE measurements of PVA and Fe3+-doped thin films are carried out at an incidence angle of 75° over the wavelength range of 0.24–1.1 μm. An optical model is used to obtain the refractive index (n) and the extinction coefficient (k). The gap energy E g is afterwards evaluated. The Fe3+ doping is found to affect strongly the optical parameters of the polymer films. In fact, an increase in the refractive index with doping is observed, resulting from the intermolecular hydrogen bonding between Fe3+ ions with the adjacent OH group of PVA. The increase of the thin films' absorption with doping is estimated by the k spectral profile analysis. The gap energy is then calculated and shows an important decrease with the Fe3+ filling, more pronounced for low doped samples. Such a behavior is confirmed by FT-IR analysis. 相似文献
282.
Nagy M. Khalifa Mostafa M. Ramla Abd El-Galil E. Amr Mohamed M. Abdulla 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):3046-3062
A series of some new acetylated S-glycosides of pyridine-2-thione derivatives, including D-glucose, D-galactose, D-xylose and L-arabinose derivatives were synthesized. Oxidation of some formed S-glycosides derivatives with H2O2 afforded the corresponding sulfones. S-Alkylation of pyridine-2-thione derivatives was performed to furnish the S-acyclo deazauridine derivatives. The entire tested compound showed potent anti-inflammatory activity were potent against edema and in the same time inhibited the prostaglandine formation. It is work mention that all the tested compounds showed high safety margin. The structures of the new synthesized compounds have been proved by IR, 1 HNMR, mass spectra and elemental analysis. 相似文献
283.
Ali A. Alhazime M. ME. Barakat Radiyah A. Bahareth E. M. Mahrous Saad Aldawood S. Abd El Aal and S. A. Nouh 《中国物理 B》2022,31(9):97802-097802
We applied an ex-situ casting procedure to prepare a nanocomposite (NCP) from Makrofol polycarbonate (PC) and CdSe nanoparticles. The CdSe nanoparticles were prepared by a thermolysis procedure in the presence of N2 gas flow. Rietveld refinement of x-ray data illustrated that the CdSe adopts a cubic zinc blend structure of 6.057 Å lattice parameter and 2 nm typical grain size. Samples from the prepared NCP were exposed to γ dosages (20 kGy-250 kGy). The modifications induced in the NCP films owing to γ dosages have been studied. The γ irradiation (50 kGy-250 kGy) causes crosslinks that reduce the optical bandgap from 4.15 eV to 3.81 eV, associated with an increase in dielectric parameters and refractive index. This is attributed to an increase in the mass fraction of the disordered regions as specified by x-ray diffraction. The PC-CdSe NCP was found to have a reaction to color modification which makes it suitable for saleable reproduction on a printing press. 相似文献
284.
Design,Docking, and Synthesis of Some New Pyrazoline and Pyranopyrazole Derivatives as Anti‐inflammatory Agents 下载免费PDF全文
Magda M. F. Ismail Nagy M. Khalifa Hoda H. Fahmy Eman S. Nossier Mohamed M. Abdulla 《Journal of heterocyclic chemistry》2014,51(2):450-458
Design and synthesis of some novel pyrazoline and pyranopyrazole derivatives as potential anti‐inflammatory agents are described. Most of the compounds were tested for their anti‐inflammatory (in vitro and in vivo) and ulcerogenic activities. In all tested compounds, it was found that pyrazolines, 2a , and pyrazolopyrano[2,3‐d]pyrimidine 9 are the potent anti‐inflammatory and selective cyclooxygenase‐2 (COX‐2) inhibitor. All compounds are mainly in the safe level. Docking study of 2a and 9 revealed higher affinity for binding with the active site of COX‐2 enzyme like SC‐558, a selective COX‐2 inhibitor. 相似文献
285.
Nagy M. Khalifa Mosaad S. Mohamed Magdi E. Zaki Mohamed A. Al-Omar Yasser M. Zohny 《Research on Chemical Intermediates》2014,40(4):1565-1574
A series of substituted pyrene derivatives 2–15 incorporated heterocyclic and sugar moieties were synthesized and evaluated as antiviral activities using 1-acetylpyrene as a starting material. The structure assignment of the new compounds was based on chemical and spectroscopic evidence. The detailed synthesis, spectroscopic data and pharmacological activities of the synthesized compounds were reported. 相似文献
286.
Abdalrahman Khalifa Dr. Marco Giles Dr. Hamed I. Ali Dr. Samy Mohamady 《European journal of organic chemistry》2023,26(17):e202300207
Phthalimide derivatives are important in medicinal chemistry, several phthalimidation methodologies have been developed. Here, we report a facile, metal-free, and catalyst-free method for the preparation of N-phthalimides in good to excellent yield by reacting 2-(arenesulfonyl)phthalimides with various amine substrates. 相似文献
287.
Let R be a locally finite-dimensional (LFD) integral domain. We investigate two invariants ${j_R(a)={{\rm inf}}\{{\rm height}P-{\rm height} Q\}}$ , where P and Q range over prime ideals of R such that ${Q\subset aR\subseteq P}$ , and ${j(R)={\rm sup}\{j_R(a)\}}$ (called the jump of R), where a range over nonzero nonunit elements of R. We study the jump of polynomial ring and power series ring, we give many results involving jump, and specially we give more interest to LFD-domain R such that j(R)?=?1. We prove that if R is a finite-dimensional divided domain, then R is a Jaffard domain if and only if for all integer ${n,\,j(R[x_1,\ldots,x_n])=1}$ . 相似文献
288.
Antifungal Activity of Soft Tissue Extract from the Garden Snail Helix aspersa (Gastropoda,Mollusca)
Hoda H. Abd-El Azeem Gamalat Y. Osman Hesham R. El-Seedi Ahmed M. Fallatah Shaden A. M. Khalifa Mohamed M. Gharib 《Molecules (Basel, Switzerland)》2022,27(10)
Gastropods comprise approximately 80% of molluscans, of which land snails are used variably as food and traditional medicines due to their high protein content. Moreover, different components from land snails exhibit antimicrobial activities. In this study, we evaluated the antifungal activity of soft tissue extracts from Helix aspersa against Candida albicans, Aspergillus flavus, and Aspergillus brasiliensis by identifying extract components using liquid chromatography-tandem mass spectrometry (LC-MS-MS). Two concentrations of three extracts (methanol, acetone, and acetic acid) showed antifungal activity. Both acetone (1 g/3 mL) and acetic acid extracts (1 g/mL) significantly inhibited C. albicans growth (p = 0.0001, 5.2 ± 0.2 mm and p = 0.02, 69.7 ± 0.6 mm, respectively). A. flavus and A. brasiliensis growth were inhibited by all extracts at 1 g/mL, while inhibition was observed for acetic acid extracts against A. brasiliensis (p = 0.02, 50.3 ± 3.5 mm). The highest growth inhibition was observed for A. flavus using acetic acid and acetone extracts (inhibition zones = 38 ± 1.7 mm and 3.1 ± 0.7 mm, respectively). LC-MS-MS studies on methanol and acetone extracts identified 11-α-acetoxyprogesterone with a parent mass of 372.50800 m/z and 287.43500 m/z for luteolin. Methanol extracts contained hesperidin with a parent mass of 611.25400 m/z, whereas linoleic acid and genistein (parent mass = 280.4 and 271.48900 m/z, respectively) were the main metabolites. 相似文献
289.
Eslam B. Elkaeed Reda G. Yousef Mohamed M. Khalifa Albaraa Ibrahim Ahmed B. M. Mehany Ibraheem M. M. Gobaara Bshra A. Alsfouk Wagdy M. Eldehna Ahmed M. Metwaly Ibrahim H. Eissa Mohamed Ayman El-Zahabi 《Molecules (Basel, Switzerland)》2022,27(19)
Four new nicotinamide-based derivatives were designed as antiangiogenic VEGFR-2 inhibitors. The congeners were synthesized possessing the pharmacophoric essential features to bind correctly with the VEGFR-2 active pocket. All members were evaluated for their cytotoxic and VEGFR-2 inhibitory potentialities. Compound 6 was the most potent showingIC50 values of 9.3 ± 0.02 and 7.8 ± 0.025 µM against HCT-116 and HepG-2 cells, respectively, and IC50 of 60.83 nM regarding VEGFR-2 enzyme inhibition. Compound 6 arrested the growth of HCT-116 cells at the pre-G1 and G2-M phases. Further, it induced both early and late apoptosis. Additionally, compound 6 caused a significant decrease in TNF-α and IL6 by 66.42% and 57.34%, respectively. The considered compounds had similar docking performances to that of sorafenib against the VEGFR-2 (PDB ID: 2OH4). The correct binding of compound 6 with VEGFR-2 was validated using MD simulations, and MM-GPSA calculations. 相似文献