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41.
42.
Om Prakash Deepak K. Aneja Khalid Hussain Ravi Kumar Sanjiv Arora Chetan Sharma Kamal R. Aneja 《Journal of heterocyclic chemistry》2012,49(5):1091-1097
A series of new symmetrical 3,6‐bis(aryl)bis([1,2,4]triazolo)[3,4‐a:4′,3′‐c]phthalazines 9a‐l has been conveniently synthesized by oxidative cyclization of 1,4‐bis(substituted benzalhydrazino)phthalazines 8a‐l promoted by iodobenzene diacetate under mild conditions (12 examples, up to 93% yield). All the 12 compounds were tested in vitro for their antibacterial activity against two Gram‐positive bacteria, namely, Staphylococcus aureus, Bacillus subtilis and two Gram‐negative bacteria, namely, Escherichia coli and Pseudomonas aeruginosa. All the synthesized compounds were also tested for their antifungal action against two fungi, Aspergillus niger and Aspergillus flavus. 相似文献
43.
Mahato P Ghosh A Mishra SK Shrivastav A Mishra S Das A 《Chemical communications (Cambridge, England)》2010,46(48):9134-9136
Selective colorimetric detection of ATP in physiological conditions by a Zn(II)-based receptor is reported. This reagent was found to be non-toxic to the living cells and could be used for studying the growth of the yeast cells. 相似文献
44.
Success in isoelectric trapping separations critically depends on the knowledge of the accurate operational pH value of the buffering membranes used. Currently, due to a lack of easy, rapid, accurate methods that can be used for the post-synthesis determination of the operational pH value of a buffering membrane, only nominal pH values calculated from the amounts of the reagents used in the synthesis of the membranes and their acid-base dissociation constants are available. To rectify this problem, UV-absorbing and fluorescent carrier ampholyte mixtures were prepared by alkylating pentaethylenehexamine with a chromophore and a fluorophore, followed by Michael addition of acrylic acid and itaconic acid to the resulting oligoamine. Carrier ampholyte mixtures, with evenly distributed absorbance values across the 3相似文献
45.
For many orbital measures μ, on SU(n), we show that either μk ∈ L2 or μk is singular to L1. The least k for which μk ∈ L2 is determined and is shown to be the minimum k for which the k-fold product of the conjugacy class supporting the measure has positive measure. It would be interesting to know if all orbital
measures satisfy this dichotomy. 相似文献
46.
For many orbital measures μ, on SU(n), we show that either μk ∈ L2 or μk is singular to L1. The least k for which μk ∈ L2 is determined and is shown to be the minimum k for which the k-fold product of the conjugacy class supporting the measure has positive measure. It would be interesting to know if all orbital
measures satisfy this dichotomy. 相似文献
47.
G. L. N. Reddy S. Vikram Kumar J. V. Ramana Sanjiv Kumar 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(3):1455-1460
Depth profiling of titanium using the resonances at 1,007, 1,013 and 1,362 keV in 48Ti(p,γ)49V nuclear reaction (E γ = 7.9 MeV) has been investigated. The resonance at 1,362 keV with a detection sensitivity of ~5.1 × 1020 at. cm?3 (~ 1 at.%), probing depth of ~800 nm and a depth resolution of ~24 nm in silicon is best suited for analytical applications. Lower probing depth and lesser detection sensitivity are the major limitations of the two other resonances. The applicability of the resonance at 1,362 keV is demonstrated by depth profiling Ti in Pd (32 nm)/Ti (57 nm)/Mg (300 nm)/Ti (57 nm)/Si multi-layered coating. 相似文献
48.
Shobhana Sharma Asha Jain Sanjiv Saxena 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1676-1688
Titanium(IV) complexes of the general formula TiL(OPr i )2 [where LH2 = R CH3 where R = ─C6H5, ─C6H4Cl(p)] were prepared by the interaction of titanium isopropoxide with sterically hindered Schiff bases derived from heterocyclic β -diketones in 1:1 molar ratio in dry benzene. The complexes TiL(OPr i )2 were used as versatile precursors for the synthesis of other titanium(IV) complexes. Titanium(IV) complexes of the type TiLL'(OPr i ) (where L'H═R1R2C═NOH, R1 = R2 = ─CH3; R1 = ─CH3,R2 = ─C6H5; R1 = ─COC6H5, R2 = ─C6H5) were synthesized by the reaction of TiL(OPr i )2 with ketooximes (L'H) in equimolar ratio in dry benzene. Another type of titanium(IV) complexes having the general formula TiLGH(OPr i ) (where GH2═HO─G─OH, G = ─CH2─CH2─) have been prepared by the reaction of TiL(OPr i )2 with glycol in 1:1 molar ratio in dry benzene. Plausible structures of these new titanium(IV) complexes have been proposed on the basis of analytical data, molecular weight measurements, and spectral studies. 相似文献
49.
Shobhana Sharma Asha Jain Sanjiv Saxena 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1689-1701
Zirconium(IV) Schiff base chelates having the general formula ZrL(OPr i )2 [where LH 2 = R CH 3 , R = –C 6 H 5 , –C 6 H 4 Cl(p)] were synthesized by the reaction of Zr(OPr i )4.Pr i OH with sterically constrained sulfur-containing Schiff bases of heterocyclic β -diketones in a 1:1 molar ratio in dry refluxing benzene. The complexes ZrL(OPr i ) 2 were used as important precursors for the synthesis of the complexes of the type Zr(L) 2 . The complexes, Zr(L) 2 , were prepared by the interaction of precursor ZrL(OPr i ) 2 with sterically constrained sulfur-containing Schiff bases of heterocyclic β -diketones in a 1:1 molar ratio in dry benzene. The structures of these zirconium(IV) chelates have been discerned with the help of elemental analyses, physicochemical studies, and spectral [IR and NMR ( 1 H and 13 C)] data. A distorted trigonal bipyramidal and a distorted octahedral geometry may be assigned to zirconium(IV) chelates of the types ZrL(OPr i ) 2 and Zr(L) 2 , respectively. 相似文献
50.
Sanjiv Arora Deepak K. Aneja Mahesh Kumar Chetan Sharma Om Prakash 《Journal of Thermal Analysis and Calorimetry》2013,111(1):17-25
A series of new unsymmetrical 2,5-disubstituted 1,3,4-oxadiazoles (3a–d) has been synthesized to evaluate their antibacterial and thermal properties. All compounds have been tested for their in vitro antibacterial activity against two Gram-positive bacteria namely, Staphylococcus aureus and Bacillus subtilis. Among the tested compounds, compound 2-(4-chlorophenyl)-5-(thiophen-2-yl)-1,3,4-oxadiazole (3c) has been found to be most potent member having minimum inhibitory concentration. Thermal stability and melting point of compounds have been studied by TG and DSC analysis in air atmosphere at heating rate of 10 °C min?1. Thermal degradation kinetics of the most potent antibacterial compound 3c has been carried out by multiple heating rate model free kinetic methods namely, Ozawa–Flynn–Wall, modified Coats-Redfern, and Kissinger. 相似文献