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171.
Dr. M. Kumari 《Heat and Mass Transfer》1988,23(4):219-227
The flow, heat and mass transfer at the stagnation point of a three-dimensional body in unsteady laminar compressible fluid with variable properties have been studied using a second-order boundary-layer theory when the basic potential flow admits selfsimilarity. Both nodal and saddle point regions have been considered. The equations governing the flow have been solved numerically using an implicit finite-difference scheme. It is observed that the enhancement or reduction in the skin friction and heat transfer due to the second-order boundary layers depends upon the values of the parameter characterizing the unsteadiness in the free-stream velocity, the nature of the stagnation point, the variation of the density-viscosity product across the boundary layer, mass transfer and the wall temperature. The suction increases the skin friction and heat transfer whereas injection does the opposite. 相似文献
172.
M. Thankamony B. Sindhu Kumari G. Rijulal K. Mohanan 《Journal of Thermal Analysis and Calorimetry》2009,95(1):259-266
Condensation of 2-amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene with carbonyl compounds such as isatin, o-hydroxyacetophenone or benzoin in 1:1 ratio in ethanol medium yielded three distinctly different heterocyclic Schiff bases
viz. 2-(N-indole-2-one)amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene (ISAT), 2-(N-o-hydroxyacetophenone)amino- 3-carboxyethyl-4,5,6,7-tetrahydro-benzo[b]thiophene (HAAT) or 2-(N-benzoin)amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene
(HBAT) respectively. These ligands formed well defined complexes with lanthanum(III) chloride under suitable conditions.
The ligands and the complexes have been characterized on the basis of elemental analyses, molar conductance measurements,
UV-visible, IR and proton NMR spectral studies. Kinetics and mechanism of the thermal decomposition of the ligands and the
metal complexes have been studied using non-isothermal thermogravimetry. Kinetic parameters were calculated for each step
of the decomposition reactions using Coats-Redfern equation. The rate controlling process for all the ligands and complexes
is random nucleation with the formation of one nucleus on each particle (Mampel equation). Relative thermal stabilities of
the ligands and the metal complexes have been compared. 相似文献
173.
Vijai Singh Pallavi Somvanshi Gaurav Rathore D. Kapoor B. N. Mishra 《Applied biochemistry and biotechnology》2010,160(7):1985-1991
Aerolysin is a significant virulent toxin protein secreted by Aeromonas hydrophila; it produces deep wound infections and hemorrhagic septicemia. The complete aerolysin gene (1,482 bp) was amplified from
A. hydrophila. Furthermore, it was cloned and expressed into Escherichia coli BL21(DE3) codon plus RP cells using 0.5 mM IPTG for induction. The protein size was 54 kDa as estimated by SDS-PAGE, and
it was purified by Ni–NTA affinity chromatography. Anti-His antibodies were used to characterize the expressed aerolysin by
Western blotting and showed hemolytic activity with fish red blood cells. Aerolysin may be used as immunoassays for earlier
control of A. hydrophila and is also compatible for vaccination. 相似文献
174.
Group 6 metal (Cr, Mo, and W)-bis(toluene) sandwich complexes are synthesized in a laser-vaporization molecular beam source. Conformational isomers and isomerization of these complexes are studied by variable-temperature pulsed-field-ionization zero-electron-kinetic-energy spectroscopy and density functional theory. For Cr-bis(toluene), four rotational conformers are identified with methyl-group dihedral angles of 0, 60, 120, and 180°. The ground electronic states of these conformers are (1)A(1) (C(2v), 0°), (1)A (C(2), 60 and 120°), and (1)A(g) (C(2h), 180°) in the neutral form and (2)A(1) (C(2v), 0°), (2)A (C(2), 60 and 120°), and (2)A(g) (C(2h), 180°) in the singly charged cationic form. For Mo- and W-bis(toluene), the four rotamers are resolved into three (0, 60/120, and 180°) and two (0 and 60/120/180°) groups, respectively. For all three metal sandwiches, the most stable conformer is in the complete eclipsed configuration (0°) and has the highest ionization energy. The conversion from 60/120/180° to 0° rotamer is observed from helium to argon supersonic expansions and is more efficient for the heavier Mo and W species. 相似文献
175.
A. G. Pinkus Jason A. Kautz Pallavi Ahobila-Vajjula 《Journal of chemical crystallography》2003,33(3):181-186
The crystal structures of 2,6-dichlorobenzoic acid (1) and 3,5-dichlorobenzoic acid (2) were obtained by single-crystal X-ray diffraction. Crystallization of 1 occurred in the centrosymmetric triclinic space group P1 (No. 2) with a = 7.2678(9), b = 9.8543(8), and c = 11.8290(11) Å = 95.000(7), = 104.262(10), and = 102.128(8); and Z = 4. Crystallization of 2 occurred in the monoclinic centrosymmetric space group P21/n (No. 14) with a = 3.7812(3), b = 13.996(2), and c = 14.514(2) Å = 95.183(8); and Z = 4. Chlorine substituents of four dimeric molecules of 2 formed square channels, ca. 3.54 Å on a side, which run parallel to the crystallographic a axis. Monomers of 1 and 2 formed centrosymmetric dimers via near-linear hydrogen bonds. Details of the structures and spectroscopic results are presented and discussed. 相似文献
176.
Reactions of 6-(1′-phenylvinyl)-1,2,4-trioxanes 2-5, with FeCl2·4H2O, FeBr2, and a combination of hemin (bovine) and reduced glutathione (GSH) under various conditions have been studied. 相似文献
177.
Mari Sithambaram Karthikeyan Bantwal Shivarama Holla Balakrishna Kalluraya Nalilu Suchetha Kumari 《Monatshefte für Chemie / Chemical Monthly》2007,138(12):1309-1316
Summary. A series of dichlorofluorophenyl containing triazolothiadiazoles were obtained by cyclocondensation of triazole with substituted
benzoic, aryloxyacetic, and anilinoacetic acids using POCl3 as cyclizing agent. The structures of the newly synthesized compounds were characterized and confirmed by IR, 1H NMR, mass spectra, and elemental analysis. Selected compounds were screened for their antitubercular activity against Mycobacterium tuberculosis. The compound bearing 2,4-dichloro-5-fluorophenyl moiety at position 3, and 6 of the triazolothiadiazole showed excellent
activity in vitro primary screening. Compounds with 3-chloro-4-fluorophenyl and 4-fluorophenoxymethyl moieties at position 6 of the triazolothiadiazole
showed very good analgesic activity. Triazolothiadiazole with 4-chlorophenyl, 4-fluoro-3-phenoxyphenyl, and 2,4-dichloro-5-fluorophenyl
moieties showed excellent antimicrobial activity against the tested strains at 6.25 μg cm−3 concentrations. 相似文献
178.
The design and facile conversion of naturally occurring 4-hydroxyproline to all four diastereomers of thymine pyrrolidine PNA monomer, (2R,4S)-adenine, -guanine and -cytosine monomers and their incorporation into duplex forming PNA oligomers is reported. The interesting results of the hybridization studies with complementary DNA/RNA sequences in either parallel or antiparallel orientation reveal the stereochemistry-dependent DNA vs. RNA discriminations and parallel/antiparallel orientation selectivity. 相似文献
179.
Sharmila Kameyanda Poonacha Madhyastha Harishkumar Madhyastha Radha Remya Varadarajan Suchetha Kumari Nalilu Shilpa Sharathraj Shetty Praveen Kumar Shetty Revanasiddappa Bistuvalli Chandrashekharappa Mahendra Gowdru Sreenivas Satheesh Kumar Bhandary Bavabeedu 《Molecules (Basel, Switzerland)》2021,26(24)
Oroxylum indicum, of the Bignoniaceae family, has various ethnomedical uses such as an astringent, anti-inflammatory, anti-bronchitis, anti-helminthic and anti-microbial, including anticancer properties. The druggability of OI stem bark extract was determined by its molecular docking interactions with PARP and Caspase-3, two proteins involved in cell survival and death. Note that 50 µg/mL of Oroxylum indicum extract (OIE) showed a significant (p < 0.05%) toxicity to HSC-3 cells. MTT aided cell viability and proliferation assay demonstrated that 50 µg/mL of OIE displayed significant (p < 0.5%) reduction in cell number at 4 h of incubation time. Cell elongation and spindle formation was noticed when HSC-3 cells were treated with 50 µg/mL of OIE. OIE initiated DNA breakage and apoptosis in HSC-3 cells, as evident from DNA ladder assay and calcein/EB staining. Apoptosis potential of OIE is confirmed by flow cytometer and triple-staining (live cell/apoptosis/necrosis) assay. Caspase-3/7 fluorescence quenching (LANCE) assay demonstrated that 50 µg/mL of OIE significantly enhanced the RFU of caspases-3/7, indicating that the apoptosis potential of OIE is probably through the activation of caspases. Immuno-cytochemistry of HSC-3 cells treated with 50 µg/mL of OIE showed a significant reduction in mitochondrial bodies as well as a reduction in RFU in 60 min of incubation time. Immunoblotting studies clearly showed that treatment of HSC-3 cells with OI extract caused caspase-3 activation and PARP deactivation, resulting in apoptotic cell death. Overall, our data indicate that OIE is an effective apoptotic agent for human squamous carcinoma cells and it could be a future cancer chemotherapeutic target. 相似文献
180.
M. Rathna Kumari P. Suresh Kumar C. Subramanian 《Crystal Research and Technology》2002,37(11):1172-1179
Effect of oxygen partial pressure on the nucleation kinetics of orthorhombic YBCO from tetragonal phase has been studied using classical nucleation theory. The free energy of formation of orthorhombic YBCO has been evaluated as a function of oxygen partial pressure. 相似文献