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21.
Hilal Goktas Dogan Mansuroglu Betul Atalay Sinan Bilikmen Ismet Kaya 《Plasma Chemistry and Plasma Processing》2012,32(1):35-44
The synthesis of polyfluorene (PF) thin films by simultaneously superposing a continuous and pulsed discharge and the characterizations
of these samples are presented. The double discharge plasma system is constructed by superposing two discharges; namely, a
low pressure dc glow one and a high current pulsed one. The fluorene monomer in powder form was vaporized in the system at
argon plasma without any modification, at 0.5 mbar operating pressure. The structure of the thin films was investigated via
XPS, UV–visible, FTIR, XRD and SEM. The FTIR and the UV–visible results revealed that the fluorene structure was retained
at the produced samples. Semi-conducting behavior was established, and upon the iodine doping, the optical energy band gap
(E
g
) dropped down from 3.7 to 2.4 eV. The morphology of the synthesized PF thin films was amorphous, with granular structures
of different sizes depending on the location of the substrate. 相似文献
22.
Polycaprolactone (PCL) based α,ω-methacrylated macromonomer (DMPCL) was synthesized via enzymatic ring-opening polymerization (eROP) by using Novozyme 435 as the enzyme immobilized catalyst. DMPCL was further photopolymerized with monofunctional poly(ethylene glycol) methyl ether methacrylate (PEGMA-950) macromonomer and trimethylolpropane triacrylate (TMPTA) as tri-functionalized crosslinking agent in glass vials when CHCl3 was the solvent and Irgacure 819 was the photoinitiator. Ultraviolet (UV) Light Emitting Diode (LED) bulbs enabled photoinduced reactions at room temperature with low heat generation and high reaction efficiency. The obtained gels were characterized with Fourier Transform Infrared Spectroscopy (FT-IR) and Differential Scanning Calorimetry (DSC). DMPCL participated as an effective crosslinking agent in the photopolymerization of PEGMA-950. Combined usage of DMPCL and PEGMA-950 resulted in significantly more effective polymerization than the separate photopolymerizations of these macromonomers. 相似文献
23.
We investigate the resonant production of color octet muons in order to explore the discovery potential of Future Circular Collider(FCC)-based μp colliders.It is shown that the search potentials of μp colliders essentially surpass the potential of the LHC and would exceed that of the FCC pp collider. 相似文献
24.
The transport of Hg (II) ions from an aqueous solution into an aqueous receiving solution through bulk and supported liquid membranes containing a calix[4]arene derivative 1 as a carrier was examined. The kinetic parameters of bulk liquid membrane studies were analyzed assuming two consecutive, irreversible first‐order reactions. The influence of temperature, stirring rate, carrier concentration and solvent on the kinetic parameters (k1, k2, Rm max, tmax, Jd max, Ja max) has also been investigated. The membrane entrance rate, k1, and the membrane exit rate, k2, increased with increasing temperature and stirring rate. The activation energy values are calculated as 4.87 and 48.63 kj mol?1 for extraction and reextraction, respectively. The values of calculated activation energy indicate that the process is diffusionally controlled by species. Also, the transport behavior of Hg2+ from aqueous solution through a flat‐sheet supported liquid membrane has been investigated by the use of calix[4]arene derivative 1 as carrier and Celgard 2500 as the solid support. A Danesi mass transfer model was used to calculate the permeability coefficients for each parameter studied. The highest values of permeability were obtained with 2‐nitrophenyloctyl‐ether (NPOE) solvent and the influence was found to be in the order of NPOE>chloroform>xylene. 相似文献
25.
26.
New epoxy resins were prepared from hydroxyl substituted Schiff base monomers in two steps. The first step is based on the synthesis of hydroxyl substituted Schiff base monomers via condensation reaction. The second step includes the reaction between Schiff base monomers with epichlorohydrine (EPC) to obtain epoxy resins. The structures of resulting compounds were confirmed by FTIR and 1H-NMR. TG-DTA and DSC measurements were made for thermal characterizations of the compounds. Chemical resistances of the cured epoxy-amine systems in acidic, alkaline and organic solvents were determined for coating applications. HCl (aqueous solution, 10%), NaOH (aqueous solution, 10%), DMSO, DMF, N-methylpyrrolidone, ethanol, THF and acetone were used for corrosion tests. Chemical resistance data show that the synthesized resins have good chemical resistance against various acid, alkaline and common organic solvents. 相似文献
27.
Hybrid phospholipid bilayer coatings for separations of cationic proteins in capillary zone electrophoresis
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Elyssia S. Gallagher Seid M. Adem Leonard K. Bright Isen A. C. Calderon Elisabeth Mansfield Craig A. Aspinwall 《Electrophoresis》2014,35(8):1099-1105
Protein separations in CZE suffer from nonspecific adsorption of analytes to the capillary surface. Semipermanent phospholipid bilayers have been used to minimize adsorption, but must be regenerated regularly to ensure reproducibility. We investigated the formation, characterization, and use of hybrid phospholipid bilayers (HPBs) as more stable biosurfactant capillary coatings for CZE protein separations. HPBs are formed by covalently modifying a support with a hydrophobic monolayer onto which a self‐assembled lipid monolayer is deposited. Monolayers prepared in capillaries using 3‐cyanopropyldimethylchlorosilane (CPDCS) or n‐octyldimethylchlorosilane (ODCS) yielded hydrophobic surfaces with lowered surface free energies of 6.0 ± 0.3 or 0.2 ± 0.1 mJ m?2, respectively, compared to 17 ± 1 mJ m?2 for bare silica capillaries. HPBs were formed by subsequently fusing vesicles comprised of 1,2‐dilauroyl‐sn‐glycero‐3‐phosphocholine or 1,2‐dioleoyl‐sn‐glycero‐3‐phosphocholine to CPDCS‐ or ODCS‐modified capillaries. The resultant HPB coatings shielded the capillary surface and yielded reduced electroosmotic mobility (1.3–1.9 × 10?4 cm2 V?1s?1) compared to CPDCS‐ and ODCS‐modified or bare capillaries (3.6 ± 0.2 × 10?4 cm2 V?1s?1, 4.8 ± 0.4 × 10?4 cm2 V?1s?1, and 6.0 ± 0.2 × 10?4 cm2 V?1s?1, respectively), with increased stability compared to phospholipid bilayer coatings. HPB‐coated capillaries yielded reproducible protein migration times (RSD ≤ 3.6%, n ≥ 6) with separation efficiencies as high as 200 000 plates/m. 相似文献
28.
Ayten Behçet Aydın Aktaş Yetkin Gök Rüya Kaya Parham Taslimi İlhami Gülçin 《Journal of heterocyclic chemistry》2021,58(2):603-611
Herein, novel silver-based N-heterocyclic carbene (NHC) complexes bearing 2-(4-hydroxyphenyl)ethyl group were synthesized. Novel Ag(I)NHC complexes were synthesized from the 2-(4-hydroxyphenyl)ethyl-substituted benzimidazolium salts and silver oxide via in situ deprotonation method. The successful formation of all Ag(I)NHC complexes was proved by using 1H NMR, 13C NMR, FTIR spectroscopy, and elemental analysis techniques. In addition, their inhibitory effects have been investigated of these substances on acetylcholinesterase (AChE), α-glycosidase (α-Gly), human carbonic anhydrase I (hCA I), and human carbonic anhydrase II (hCA II) enzymes. It has been seen that all compounds have a better ability to inhibit compared with existing tried inhibitors. Among these, the best inhibitor against AChE enzyme is 1g (Ki : 9.54 ± 0.98 μM and IC50 : 17.40), and against α-Gly, 1c showed the highest effect (Ki 3.09 ± 0.36 μM and IC50 7.91). The best inhibitor against hCA I and hCA II enzymes are 1c and 1g compounds. For hCA I and hCA II, IC50 values were calculated as 17.85 and 9.06 μM and Ki values were measured as 5.45 ± 2.02 and 8.99 ± 2.02 μM, respectively. 相似文献
29.
Rambabu Sirgamalla Kurumanna Adem Sakram Boda Ashok Kommakula Suryam Neradi Shyam Perka Kiran Bojja Mohammed Arifuddin 《Journal of heterocyclic chemistry》2020,57(9):3375-3383
We report herein DABCO mediated one pot synthesis of 2-(3-benzyl-2, 6-dioxo-3,6-dihydropyrimidin-1[2H]-yl)-N-(4-(1,3-dioxo-1H-benzo[de]isoquinolin-2[3H]-yl) aryl) acetamides ( 4a-j ). The silent features of this new one pot synthesis include the shorter reaction time, high yields, simple workup, and simultaneous formation of N-Amide and N-benzyl bonds in the one pot. The newly synthesized compounds ( 4a-j ) were characterized by different spectral techniques such as IR, 1H-NMR, 13C-NMR, HRMS. All the synthesized compounds were evaluated for their anti-bacterial and anti-fungal activities. The anti-bacterial activities results reveal that the compounds 4a , 4g , 4i , and 4j are most active against S. aureus. In the case of B. subtilis the compounds 4a , 4i , and 4j are found to be most active. The compounds 4c , 4e , 4i , and 4j are most active against E. coli. In the case of P. aeruginosa 4a , 4i & 4j are found to be more active. On the other hand, the anti-fungal activity result shows that the compounds 4d , 4f , 4i , and 4j are more active against A. niger. The compounds 4a , 4d , 4i , and 4j are found to be more active against C. albicans. 相似文献
30.
Gülhan Turan Begüm Nurpelin Sağlik Ulviye Acar Çevik Serkan Levent Betül Kaya Çavuşoğlu 《Phosphorus, sulfur, and silicon and the related elements》2020,195(6):491-497
AbstractIn this study, a novel series of benzothiazole-thiazolylhydrazine (3a–3i) was synthesized and their structures were characterized by 1H-NMR, 13C-NMR spectrometry, and mass spectroscopy. These compounds were evaluated as inhibitors of type A and type B monoamine oxidase (MAO) enzymes. The most active compound 3b (2-((2-(2-(4-(4-Nitrophenyl)thiazol-2-yl)hydrazineylidene)-2-phenylethyl)thio)benzothiazole) showed strong inhibitory activity at hMAO-A (IC50 of 0.095?±?0.004?µM). Furthermore, compound 3i (2-((2-(2-(4-(2,4-dichlorophenyl)thiazol-2-yl)hydrazineylidene)-2-phenylethyl)thio)benzothiazole) showed significant inhibition profile on hMAO-A with the IC50 values 0.141?±?0.006?µM. 相似文献