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661.
Hadi Salari Seyedsaeid Ahmadvand Ali Reza Harifi-Mood Mohsen Padervand Mohammad Reza Gholami 《Journal of solution chemistry》2013,42(9):1757-1769
Structural and molecular-microscopic properties of the solvatochromic probes 4-nitroaniline, 4-nitroanisole, and Reichardt’s dye were investigated in binary mixtures of ethylammonium propionate with methanol, ethanol, 1-propanol and 2-propanol. Solvatochromic parameters (α, hydrogen-bond donor acidity; β, hydrogen-bond acceptor basicity; π*, dipolarity/polarizability; $ E_{\text{T}}^{\text{N}} $ , normalized polarity parameter) in different binary mixtures of ionic liquid with molecular solvents were determined with UV–Vis spectroscopy. The $ E_{\text{T}}^{\text{N}} $ parameters show nearly ideal trends in all solvent mixtures, but the other parameters show different behavior in the mixtures. The π* parameters show a negative deviation from ideality in the ionic liquid/methanol system. In contrast, the α parameters have severe positive deviations from ideal behavior in ionic liquid/1-propanol and ionic liquid/2-propanol solvent mixtures. A synergistic solvation effect is observed for the π* parameters in IL/methanol mixtures. Specific solute–solvent interactions or solvent–solvent interactions, which cause non-ideal trends in some parameters, are justified and interpreted by the preferential solvation model. 相似文献
662.
Hadi Z. Fazlelahi Peyman N. Moghadam Mehdi M. Baradarani John A. Joule 《Journal of heterocyclic chemistry》2020,57(10):3673-3684
New pyrazolo[4′,3′:5,6]pyrido[2,3-d]pyrimidines, with an associated spiro-3,3′-oxindole attachment, were prepared by three-component combinations of 5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinoline-1,2-dione with a pair of reactants chosen from a pyrazol-5-one, a pyrazole-5-amine, a barbituric acid, or a 6-aminouracil. 相似文献
663.
A novel mixed-ligand complex of [In(Me-phen)Cl3(DMSO)] (1) was acquired and specified via spectral approaches (IR, UV–Vis, 1H-NMR, and luminescence), thermal evaluation such as thermogravimetric, differential thermal analyses, and single-crystal X-ray diffraction. In this study, we have also reported the nanosize of [In(Me-phen)Cl3(DMSO)] (1) that has been synthesized via the sonochemical process. Characterization of nanoparticle (1) was carried out via X-ray powder diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy. The sample size assembled via the sonochemical approach was approximately 20 nm. Also, a novel screen-printed electrode modified with indium nanocomplex (In NC/SPE) was developed. An electrochemical examination of the adjusted electrode in addition to its efficiency in dopamine electro-oxidation is explained. It was proven that dopamine oxidation at adjusted electrode surface takes place at 150 mV potential less positive compared to an unadjusted screen-printed electrode. The relevant detection limit for dopamine was 2.0 × 10−7 M via differential pulse voltammetry. Moreover, the adjusted electrode was utilized to simultaneously determine dopamine and acetylcholine. Lastly, the adjusted electrode was utilized to determine dopamine and acetylcholine within real specimens. 相似文献
664.
Dr. Haifeng Zheng Kuiyong Dong Dr. Daniel Wherritt Dr. Hadi Arman Prof. Dr. Michael P. Doyle 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(32):13715-13719
The direct Friedel–Crafts-type coupling and dedinitrogenation reactions of vinyldiazo compounds with aromatic compounds using a metal-free strategy are described. This Brønsted acid catalyzed method is efficient for the formation of α-diazo β-carbocations (vinyldiazonium ions), vinyl carbocations, and allylic or homoallylic carbocation species via vinyldiazo compounds. By choosing suitable nucleophilic reagents to selectively capture these intermediates, both trisubstituted α,β-unsaturated esters, β-indole-substituted diazo esters, and dienes are obtained with good to high yields and selectivity. Experimental insights implicate a reaction mechanism involving the selective protonation of vinyldiazo compounds and the subsequent release of dinitrogen to form vinyl cations that undergo intramolecular 1,3- and 1,4- hydride transfer processes as well as fragmentation. 相似文献
665.
Sulfonated Sulfurol supported Fe3O4 (Fe3O4@SiO2-Pr-Sulfurol-SO3H) a new magnetic reusable nanocatalyst was prepared using chemical modification of magnetic nanoparticles (MNPs) surface with Sulfurol-SO3H. The Sulfurol-SO3H moieties on the surface of MNPs act as acidic catalytic sites for catalysis purposes. Fe3O4@SiO2-Pr-Sulfurol-SO3H was authenticated by usual analytical and spectroscopic techniques. The prepared Fe3O4@SiO2-Pr-Sulfurol-SO3H MNPs were applied to the preparation of novel Spiro[acridine-9,5′-thiazole]-1,4′-dione derivatives via the three-component condensation of isatins, dimedone and thioamides or thioureas.
相似文献666.
Haifeng Zheng Kuiyong Dong Daniel Wherritt Hadi Arman Michael P. Doyle 《Angewandte Chemie (International ed. in English)》2020,59(32):13613-13617
The direct Friedel–Crafts‐type coupling and dedinitrogenation reactions of vinyldiazo compounds with aromatic compounds using a metal‐free strategy are described. This Brønsted acid catalyzed method is efficient for the formation of α‐diazo β‐carbocations (vinyldiazonium ions), vinyl carbocations, and allylic or homoallylic carbocation species via vinyldiazo compounds. By choosing suitable nucleophilic reagents to selectively capture these intermediates, both trisubstituted α,β‐unsaturated esters, β‐indole‐substituted diazo esters, and dienes are obtained with good to high yields and selectivity. Experimental insights implicate a reaction mechanism involving the selective protonation of vinyldiazo compounds and the subsequent release of dinitrogen to form vinyl cations that undergo intramolecular 1,3‐ and 1,4‐ hydride transfer processes as well as fragmentation. 相似文献
667.
Dr. Qing‐Qing Cheng Lynée A. Massey Brook S. Willett Dr. Yongming Deng Dr. Hadi Arman Prof. Dr. Michael P. Doyle 《Angewandte Chemie (International ed. in English)》2018,57(32):10343-10346
Enoldiazoimides, a new subclass of enoldiazo compounds, generate enol‐substituted carbonyl ylides whose reactions with sulfur ylides enable an unprecedented formal [4+2] cycloaddition. The resulting multifunctionalized indolizidinones, which incorporate sulfur, are formed in good yields under mild reaction conditions. The uniqueness of this transformation stems from the role of the silyl‐protected enol, since the corresponding acetyldiazoimide failed to provide any cross‐products in metal‐catalyzed reactions with sulfur ylides. This copper‐catalyzed cycloaddition is initiated with the generation of enol‐substituted carbonyl ylides and sulfur ylides from enoldiazoimides and sulfonium salts, respectively, and proceeds through stepwise six‐membered ring formation, C?O and C?S bond cleavage, and silyl and acetyl group migration. 相似文献
668.
Amin Reyhani Mitchell D. Nothling Hadi Ranji‐Burachaloo Dr. Thomas G. McKenzie Dr. Qiang Fu Dr. Shereen Tan Prof. Gary Bryant Prof. Greg G. Qiao 《Angewandte Chemie (International ed. in English)》2018,57(32):10288-10292
The use of hemoglobin (Hb) contained within red blood cells to drive a controlled radical polymerization via a reversible addition‐fragmentation chain transfer (RAFT) process is reported for the first time. No pre‐treatment of the Hb or cells was required prior to their use as polymerization catalysts, indicating the potential for synthetic engineering in complex biological microenvironments without the need for ex vivo techniques. Owing to the naturally occurring prevalence of the reagents employed in the catalytic system (Hb and hydrogen peroxide), this approach may facilitate the development of new strategies for in vivo cell engineering with synthetic macromolecules. 相似文献
669.
Mehdi Baghayeri Hojat Veisi Samaneh Farhadi Hadi Beitollahi Behrooz Maleki 《Journal of the Iranian Chemical Society》2018,15(5):1015-1022
We studied a rapid, sensitive and selective amperometric sensor for determination of hydrogen peroxide by electrodeposited Ag NPs on a modified glassy carbon electrode (GCE). The modified GCE was constructed through a step by step modification of magnetic chitosan functional composite (Fe3O4–CH) and high-dispersed silver nanoparticles on the surface. The resulted Ag@Fe3O4–CH was characterized by various analytical methods including Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, scanning electron microscopy and cyclic voltammetry. The proposed sensor employed Ag@Fe3O4–CH/GCE as the working electrode with a linear current response to the hydrogen peroxide concentration in a wide range from 0.01 to 400 µM with a low limit of detection (LOD = 0.0038 µM, S/N = 3). The proposed sensor showed superior reproductivity, sensitivity and selectivity for the detection of hydrogen peroxide in environmental and clinical samples. 相似文献
670.
Hadi M. Marwani 《Journal of fluorescence》2013,23(2):251-257
In the current study, spectroscopic and physicochemical properties of newly prepared ionic liquids were investigated. Ionic liquids were synthesized via a simple and straightforward route using a metathesis reaction of either N,N-diethyl-p-phenylenediamine monohydrochloride or N-phenacylpyridinium bromide with bis(trifluoromethane)sulfonimide lithium in water. High yield and purity were obtained for the resultant ionic liquids. Data acquired by use of 1H NMR and FT-IR measurements were consistent with the chemical structures of newly prepared ionic liquids. Results of thermal gravimetric analysis also implied that these ionic liquids have good thermal stability. In addition, UV–vis and fluorescence spectroscopy measurements provided that new ionic liquids are good absorbent and fluorescent. Time-based fluorescence steady-state measurements showed that ionic liquids have high photostability against photobleaching. For a deeper mechanistic understanding of the analytical potential of newly synthesized ionic liquids, spectroscopic and physicochemical parameters, including singlet absorption, extinction coefficient, fluorescence quantum yield, Stokes shift, oscillator strength and dipole moment, were also investigated. 相似文献