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排序方式: 共有292条查询结果,搜索用时 31 毫秒
251.
In this research, polysubstituted quinolines are prepared from the reaction of 2-aminobenzophenones and ethylacetoacetate or ketones in the presence of 1-butyl-3-methylimidazolium hydrogen sulfate [bmim]HSO4 as an acidic ionic liquid in good to high yields at 70 °C under solvent-free conditions. 相似文献
252.
Abdulrazzaq Tuqa Togun Hussein Goodarzi Marjan Kazi S. N. Ariffin M. K. A. Adam N. M. Hooman Kamel 《Journal of Thermal Analysis and Calorimetry》2020,140(1):373-379
Journal of Thermal Analysis and Calorimetry - In this study, catalyst formation [Pb(H2O)6][ATZ]·H2O (ATZ?=?azo tetrazolium anion) was successfully synthesized originally;... 相似文献
253.
Marjan Mollazadeh Maryam Mohammadi-Khanaposhtani Homa Azizian Afsaneh Zonouzi Zahra Abdolahi Hamid Nadri Bagher Larijani Mahmood Biglar Mohammad Mahdavi 《中国化学会会志》2020,67(10):1910-1928
2,4-Dioxochroman-pyridinium-phenylacetamide derivatives 7a–n were synthesized and evaluated for their in vitro cholinesterase (ChE) inhibitory activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Obtained results demonstrated that, among the synthesized compounds, two compounds, 7j and 7k , were more potent than the standard drug donepezil against BuChE and did not show cytotoxicity and carcinogenicity. Furthermore, through molecular modeling and molecular dynamic studies. we showed that these compounds can be located deep in the gorge cavity of BuChE and that they interacted with catalytic residues, acyl, and cholin-binding pockets of this enzyme. Support information 相似文献
254.
Masoud Bezi Javan 《Applied Physics A: Materials Science & Processing》2013,113(1):105-113
The structural, electronic and optical properties of Si n C n (n=12,16,20,30,35 and 60) nanocages were studied using different approximations of density functional theory, i.e. local density approximation (LDA), generalized gradient approximation (GGA) and density functional theory based tight binding approximation (DFTB). The highest occupied molecular orbitals (HOMO) and lowest unoccupied molecular orbitals (LUMO) energy gaps were calculated for all nanocages. Time-dependent density functional theory (TD-DFT) was also applied for estimating of the optical excitation and exciton binding energies of the nanocages and the results compared with pure DFT calculations. 相似文献
255.
Masoud Bezi Javan Samaneh Ebrahimi 《Applied Physics A: Materials Science & Processing》2014,114(2):529-536
We studied the structural, electronic, and magnetic properties of C59Ir, C58Ir2, and C69Ir heterofullerenes by employing density functional theory and the generalized gradient approximation. There are six distinct isomers of C58Ir2 with high probability to form stable structures. The most stable structure of the C69Ir heterofullerene was investigated by comparing the iridium binding energies at the different atomic sites on the D5h C70 cage. There is a strong hybridization between the atomic orbitals of the iridium and those of the carbon atoms, leading to the spin quenching of the iridium atoms in the most stable C58Ir2 heterofullerene. 相似文献
256.
On the Activation of Methane and Carbon Dioxide by [HTaO]+ and [TaOH]+ in the Gas Phase: A Mechanistic Study
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Marjan Firouzbakht Dr. Nicole J. Rijs Dr. Patricio González‐Navarrete Dr. Maria Schlangen Prof. Dr. Martin Kaupp Prof. Dr. Helmut Schwarz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(30):10581-10589
The thermal reactions of [Ta,O,H]+ with methane and carbon dioxide have been investigated experimentally and theoretically by using electrospray ionization mass spectrometry (ESI MS) and density functional theory calculations. Although the activation of methane proceeds by liberation of H2, the activation of CO2 gives rise to the formation of [OTa(OH)]+ under the elimination of CO. Computational studies of the reactions of methane and carbon dioxide with the two isomers of [Ta,O,H]+, namely, [HTaO]+ and [Ta(OH)]+, have been performed to elucidate mechanistic aspects and to explain characteristic reaction patterns. 相似文献
257.
Pourya Seyfi Amir Heidari Ahmad Khademi Mehrdad Golghand Marjan Gharavi Hamid Ghomi 《等离子体物理论文集》2021,61(3):e202000155
In this paper, the dynamics and flow behaviour of an atmospheric argon plasma jet was studied in the new nozzle structure similar to the surface dielectric barrier discharge (SDBD) using the Schlieren imaging method. The effect of plasma jet driven by repetitive high-voltage microsecond pulses with low-frequency sinusoidal bias was measured qualitatively in a single mirror Schlieren optical system. The enhancement of plasma jet length and cross-section of plasma jet with surface in this condition is due to highly turbulent flow of argon plasma jet in this structure. This study revealed the important role of SDBD structure and modulated electric field on the behaviour of plasma jet in a high diameter nozzle. In practice, this technique allows us to increase the jet length of the nozzle output to 5 cm and under these conditions, the diameter of the plasma jet cross-section is increased to 8 mm, without increasing the electrical power consumption. Eventually, the hydrophilicity of the surface is also measured by the contact angle of a water droplet that decreases from 78° to 8° after surface treatment, implying we were able to reach a super-hydrophilic surface with this plasma jet structure. 相似文献
258.
Amir Jouya Talaei Nahid Zarei Anwarul Hasan Samir Haj Bloukh Zehra Edis Niusha Abbasi Gamasaee Marjan Heidarzadeh Mohammad Mahdi Nejadi Babadaei Koorosh Shahpasand Majid Sharifi Keivan Akhatri Suliman Khan Menzghou Xue Mojtaba Falahati 《Arabian Journal of Chemistry》2021,14(2):102923
The interaction of nanoparticles with biological systems can provide useful information about their therapeutic applications. The aluminum nanoparticles (Al2O3 NPs) were synthesized by laser ablation technique and well-characterized by different methods. Fluorescence spectroscopy, circular dichroism (CD) spectroscopy, and molecular docking studies were employed to evaluate the effect of Al2O3 NPs on the protein structure. Growth inhibitory and apoptotic effects of the Al2O3 NPs against K562 cancer cells and lymphocyte cells were assessed using [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT), flow cytometry, and real time polymerase chain reaction (PCR) assays. The antipathogenic activity of Al2O3 NPs against a diverse range of Gram-negative and Gram-positive pathogens was explored through a disk diffusion method. The characterization techniques determined that the Al2O3 NPs were successfully synthesized in the nanoscales. Intrinsic, 1-anilino-8-naphthalenesulfonate (ANS) and acrylamide fluorescence spectroscopy studies disclosed that Al2O3 NPs can partially change the tertiary structure of human serum albumin (HSA), whereas CD spectroscopy investigation depicted that the secondary structure of HSA remained intact. Molecular docking investigation also manifest that the Al2O3 nano-clusters preferably bind to electrostatic residues. Al2O3 NPs exhibited promising and selective anticancer features through reactive oxygen species (ROS) production, apoptosis induction, and elevation of Bax/Bcl-2 mRNA ratio. Furthermore, the Al2O3 NP showed a remarkable antibacterial activity against both Gram-negative and Gram-positive pathogens. In conclusion, it may be suggested that the synthesized Al2O3 NPs can be integrated in the development of anticancer and antipathogenic agents. 相似文献
259.
Marjan Motiei Luis Pleno de Gouveia Tom opík Robert Vícha David koda Jaroslav Císa Reza Khalili Eva Domincov Bergerov Luk Münster Haojie Fei Vladimír Sedlaík Petr Sha 《Molecules (Basel, Switzerland)》2021,26(7)
The alkaline milieu of chronic wounds severely impairs the therapeutic effect of antibiotics, such as rifampicin; as such, the development of new drugs, or the smart delivery of existing drugs, is required. Herein, two innovative polyelectrolyte nanoparticles (PENs), composed of an amphiphilic chitosan core and a polycationic shell, were synthesized at alkaline pH, and in vitro performances were assessed by 1H NMR, elemental analysis, FT-IR, XRD, DSC, DLS, SEM, TEM, UV/Vis spectrophotometry, and HPLC. According to the results, the nanostructures exhibited different morphologies but similar physicochemical properties and release profiles. It was also hypothesized that the simultaneous use of the nanosystem and an antioxidant could be therapeutically beneficial. Therefore, the simultaneous effects of ascorbic acid and PENs were evaluated on the release profile and degradation of rifampicin, in which the results confirmed their synergistic protective effect at pH 8.5, as opposed to pH 7.4. Overall, this study highlighted the benefits of nanoparticulate development in the presence of antioxidants, at alkaline pH, as an efficient approach for decreasing rifampicin degradation. 相似文献
260.
Aleksandar S. Cvetković Marjan M. Matejić Gradimir V. Milovanović 《Results in Mathematics》2016,69(3-4):443-455
Given numbers \({n,s \in \mathbb{N}}\), \({n \geq 2}\), and the \({n}\)th-degree monic Chebyshev polynomial of the first kind \({\widehat T_n(x)}\), the polynomial system “induced” by \({\widehat T_n(x)}\) is the system of orthogonal polynomials \({\{p_{k}^{n,s} \}}\) corresponding to the modified measure \({d \sigma^{n,s}(x)=\widehat T^{2s}_n(x) d\sigma(x)}\), where \({d\sigma(x)=1/\sqrt{1-x^{2}}dx}\) is the Chebyshev measure of the first kind. Here we are concerned with the problem of determining the coefficients in the three-term recurrence relation for the polynomials \({p^{n,s}_{k}}\). The desired coefficients are obtained analytically in a closed form. 相似文献