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1.
A. Indrasena Sd. Riyaz Prema L. Mallipeddi P. Padmaja B. Sridhar P.K. Dubey 《Tetrahedron letters》2014
A series of indolylidinepyrazolones were synthesized using a simple, green, and effective route and evaluated as anti-bacterial agents. The compounds were further studied via structure-guided docking study. One of the compounds exhibiting H-bonding interactions with conserved residue Arg144 turned out to be the most potent compound of the series. The minimum inhibitory concentration values ranged from 50 to 25 μg/mL against Staphylococcus aureus in their anti microbial evaluation. 相似文献
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Balasubramanian Sridhar Jagadeesh Babu Nanubolu Krishnan Ravikumar 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(2):128-135
A new polymorph of cytosine, C4H5N3O, is reported half a century after the report of its first known crystal structure [Barker & Marsh (1964). Acta Cryst. 17 , 1581–1587]. Cytosine thus provides the first polymorphic example in the category of parent nucleobases. The new form, denoted (Ib), was observed unexpectedly during an attempt to cocrystallize cytosine with catechol. Form (Ib) crystallizes in the orthorhombic centrosymmetric space group Pccn with two molecules in the asymmetric unit. The previously known form, denoted (Ia), crystallizes in the orthorhombic noncentrosymmetric space group P212121. The cytosine molecule is planar in both forms. Hydrogen‐bonding interactions are also similar for both forms. Infinite one‐dimensional ribbons composed of cytosine base‐pair dimers in R22(8) arrangements are observed in both (Ia) and (Ib). However, the way that the ribbons are packed differs in (Ia) and (Ib). This appears to guide the centrosymmetric versus noncentrosymmetric space‐group selection through the formation of an inversion‐related motif in polymorph (Ib) and a helical propagation in polymorph (Ia). A few selected polymorphic systems have been gathered from the Cambridge Structural Database to understand possible structural features responsible for achiral molecules adopting centro‐ and noncentrosymmetric space groups. 相似文献
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Krishnan Ravikumar Balasubramanian Sridhar Jagadeesh Babu Nanubolu Tamilselvan Rajasekaran Basi Venkata Subba Reddy 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(4):322-329
Four structures of oxoindolyl α‐hydroxy‐β‐amino acid derivatives, namely, methyl 2‐{3‐[(tert‐butoxycarbonyl)amino]‐1‐methyl‐2‐oxoindolin‐3‐yl}‐2‐methoxy‐2‐phenylacetate, C24H28N2O6, (I), methyl 2‐{3‐[(tert‐butoxycarbonyl)amino]‐1‐methyl‐2‐oxoindolin‐3‐yl}‐2‐ethoxy‐2‐phenylacetate, C25H30N2O6, (II), methyl 2‐{3‐[(tert‐butoxycarbonyl)amino]‐1‐methyl‐2‐oxoindolin‐3‐yl}‐2‐[(4‐methoxybenzyl)oxy]‐2‐phenylacetate, C31H34N2O7, (III), and methyl 2‐[(anthracen‐9‐yl)methoxy]‐2‐{3‐[(tert‐butoxycarbonyl)amino]‐1‐methyl‐2‐oxoindolin‐3‐yl}‐2‐phenylacetate, C38H36N2O6, (IV), have been determined. The diastereoselectivity of the chemical reaction involving α‐diazoesters and isatin imines in the presence of benzyl alcohol is confirmed through the relative configuration of the two stereogenic centres. In esters (I) and (III), the amide group adopts an anti conformation, whereas the conformation is syn in esters (II) and (IV). Nevertheless, the amide group forms intramolecular N—H...O hydrogen bonds with the ester and ether O atoms in all four structures. The ether‐linked substituents are in the extended conformation in all four structures. Ester (II) is dominated by intermolecular N—H...O hydrogen‐bond interactions. In contrast, the remaining three structures are sustained by C—H...O hydrogen‐bond interactions. 相似文献
4.
Cherukumalli Purna Koteswara Rao Tadiboina Bhaskara Rao Gulipalli Kali Charan Bodige Srinu Gangarapu Kiran Sridhar Gattu 《Russian Journal of General Chemistry》2020,90(10):1981-1989
Russian Journal of General Chemistry - A novel series of bis-isoxazole incorporated benzothiazole derivatives has been designed and synthesized. Molecular structures of the compounds have been... 相似文献
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A first principle study of hydrogen storage in titanium-doped small carbon clusters (C2nTin,n = 2–6)
Structural Chemistry - Hydrogen storage in Ti-doped small carbon clusters, C2nTin (n = 2–6), has been studied using density functional theory. Using the principle of maximum hardness (η)... 相似文献
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M. A. Sridhar N. K. Lokanath J. Shashidhara Prasad C. V. Yelammagad S. K. Varshney 《Liquid crystals》2013,40(1):45-49
The title compound, cholesteryl 6[4-(4-pentyloxyphenylethynyl)phenoxy]hexanoate (DMT5), a cholesterol-based dimesogen, crystallizes in the monoclinic space group P21 with the parameters a = 9.812(3) Å, b = 9.713(2) Å, c = 24.179(2) Å, β = 92.48(1)° V = 2302.2(9) Å3, Z = 2, F000 = 836, λ(MoKα) = 0.71069 Å, μ = 0.067 cm 1, final R = 0.0772. The structure has intermolecular hydrogen bonds; it is stabilized by the presence of intermolecular contacts whose spacings are less than van der Waals' radii. 相似文献
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Sridhar Madabhushi Kondal Reddy GodalaRaveendra Jillella Kishore Kumar Reddy MalluNarsaiah Chinthala 《Tetrahedron letters》2014
The synthesis of highly functionalized 2,3-dihydroisoxazoles by a one-pot multicomponent reaction of an aldehyde, hydroxamic acid, and malononitrile or methyl cyanoacetate is described. 相似文献