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181.
182.
G. Y. S. K. Swamy B. Sridhar K. Ravikumar Y. S. Sadanandam 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(2):o80-o83
The molecules of (±)‐2‐(4‐methoxyphenyl)‐1‐phenethyl‐2,3‐dihydroquinazolin‐4(1H)‐one, C23H22N2O2, (I), and (±)‐2‐(1,3‐benzodioxol‐5‐yl)‐1‐phenethyl‐2,3‐dihydroquinazolin‐4(1H)‐one, C23H20N2O3, (II), have T‐shaped forms in the crystal structure. The tetrahydropyrimidine ring in both structures adopts a sofa conformation. Both molecules are linked by N—H...O and C—H...O hydrogen bonds to form sheets built from alternating R22(8) and R44(26) [R44(24) in (II)] edge‐fused rings. Additionally, the structures are stabilized by extensive C—H...π interactions. 相似文献
183.
Chidrawar Ajay Devulapally Yogananda Chary Dr. Sridhar Balasubramanian Dr. Basi V. Subba Reddy 《European journal of organic chemistry》2023,26(13):e202201361
Rh(III)-catalyzed C−H bond annulation of 2-arylquinoxalines with cyclic 2-diazo-1,3-diketones has been accomplished for the first time to synthesize a novel series of 2,3-dihydrodibenzo[a,c]phenazin-4(1H)-one frameworks by means of carbene insertion followed by condensation. The reaction proceeds through the C−H bond activation and functionalization of 2-arylquinoxalines using Rh(III)/AgSbF6 complex to produce highly substituted 2,3-dihydrodibenzo[a,c]phenazin-4(1H)-one and benzo[5,6][1,2,4]thiadiazino[2,3-f]phenanthridin-5(6H)-one-10,10-dioxide derivatives in good to excellent yields. 相似文献
184.
4H-Chromenyl-tetrahydro-2H-pyrancarboxylates 3a–k have been conveniently prepared by the reaction of 3-formylchromones 1a–k and ethyl 4,4,4-trifluoro-3-oxobutanoate 2a with good yields. Thus obtained 4H-chromenyl-tetrahydro-2H-pyrancarboxylates 3a–k were reacted with amines 4a–e to provide series of 5-(2-hydroxybenzoyl)-2-(trifluoromethyl)-1,2-dihydropyridine-3-carboxylates 5a–o. The reaction proceeded via Michael addition (C-N bond formation) and followed by cleavage of chromone and pyran rings (C-O bond cleavage) in one pot. 相似文献
185.
Synthesis,Spectral Characterization and Antioxidant Activity of Novel Zafirlukast Sulfonyl Derivatives 下载免费PDF全文
Donka Rajasekhar Doddaga Srinivasulu Chenchugari Sridhar Godlaveti Vijay Narasimha Kumar Peddakonda Ramesh 《中国化学会会志》2016,63(3):267-274
A new series of cyclopentyl 3‐(2‐methoxy‐4‐(piperazine‐1‐carbonyl)benzyl)‐1‐methyl‐1H‐indol‐5‐ylcarbamate sulfonyl derivatives were synthesized by the reaclion of 4‐((5‐(cyclopentyloxycarbonylamino)‐1‐methyl‐1H‐indol‐3‐yl)methyl)‐3‐methoxybenzoic acid (ZAK drug intermediate) with Boc piperazine in the presence of EDC?HCl, HOBt, TEA in DMF followed by deboxylation by using 2N HCl or 35 % HCl in acetone to get an intermediate compound. Further, this compound was treated with various substituted benzene sulfonyl chlorides in the presence of TEA in THF to afford title compounds. All the title compounds were characterized by 1HNMR, 13CNMR, IR and mass spectral data. The title compounds and starting material were evaluated for their antioxidant activity by using the DPPH, H2O2 and NO methods. The results revealed that some of the compounds have shown significant antioxidant activity. 相似文献
186.
187.
Lahankar SA Chambreau SD Zhang X Bowman JM Suits AG 《The Journal of chemical physics》2007,126(4):044314
Recently, a new mechanism of formaldehyde decomposition leading to molecular products CO and H(2) has been discovered, termed the "roaming atom" mechanism. Formaldehyde decomposition from the ground state via the roaming atom mechanism leads to rotationally cold CO and vibrationally hot H(2), whereas formaldehyde decomposition through the conventional molecular channel leads to rotationally hot CO and vibrationally cold H(2). This discovery has shown that it is possible to have multiple pathways for a reaction leading to the same products with dramatically different product state distributions. Detailed investigations of the dynamics of these two pathways have been reported recently. This paper focuses on an investigation of the energy dependence of the roaming atom mechanism up to 1500 cm(-1) above the threshold of the radical channel, H(2)CO-->H+HCO. The influence of excitation energy on the roaming atom and molecular elimination pathways is reported, and the branching fraction between the roaming atom channel and molecular channel is obtained using high-resolution dc slice imaging and photofragment excitation spectroscopy. From the branching fractions and the reaction rates of the radical channel, the overall competition between all three dissociation channels is estimated. These results are compared with recent quasiclassical trajectory calculations on a global H(2)CO potential energy surface. 相似文献
188.
Dogamanti Ashok Chiranjeevi Pamula Aamate Vikas Kumar Vagolu Siva Krishna Sriram Dharmarajan Balasubramanian Sridhar Sarasija Madderla 《Molecular diversity》2021,25(4):2137-2148
Molecular Diversity - As part of an ongoing effort to develop new anti-tubercular agents, a series of novel indole-fused spirochromene hybrids (7a–l) were efficiently synthesized in excellent... 相似文献
189.
190.
Gattu Sridhar Mudavath Somnath Gangavaram V. M. Sharma Thodupunuri Prashanth 《合成通讯》2017,47(6):551-556
A ZrCl4-mediated simple method for the conversion of vinyl nitrates to 1,2,3-triazoles in excellent yields is developed. The obtained new triazoles were evaluated for their antimicrobial activity. 相似文献