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71.
J Santhanalakshmi G Shantha Lakshmi V K Aswal P S Goyal 《Journal of Chemical Sciences》2001,113(1):55-62
Small angle neutron scattering (SANS) measurements of D2O solutions (0.1 M) of sodium cholate (NaC) and sodium deoxycholate (NaDC) were carried out atT= 298 K. Under compositions very much above the critical micelle concentration (CMC), the bile salt micelle size growths were
monitored by adopting Hayter-Penfold type analysis of the scattering data. NaC and NaDC solutions show presence of correlation
peaks atQ = 0.12 and 0.1 ?-1 respectively. Monodisperse ellipsoids of the micelles produce best fits. For NaC and NaDC systems, aggregation number (9.0,
16.0), fraction of the free counterions per micelle (0.79, 0.62), semi-minor (8.0 ?) and semi-major axes (18.4, 31.7 ?) values
for the micelles were deduced. Extent of micellar growth was studied using ESR correlation time measurements on a suitable
probe incorporating NaC and NaDC micelles. The growth parameter (axial ratio) values were found to be 2.3 and 4.0 for NaC
and NaDC systems respectively. The values agree with those of SANS. 相似文献
72.
Methods to generate triplets of organic molecules within zeolites have been established by employing the Zimmerman rearrangement of barrelenes, oxa-di-π-methane rearrangement of β,γ-unsaturated ketones and photodimerization of acenaphthylene as probe reactions. The two methods, heavy cation effect and triplet sensitization, are well established solution techniques and these work well within zeolites. The Zimmerman rearrangement of dibenzobarrelene is enhanced even within Li+ and Na+ exchanged zeolites and these are believed to be the result of slowing of the rearrangement to dibenzocyclooctatetraene from S1 through cation-π interaction. The methods described here provide an opportunity to explore the control afforded by the zeolite environment on triplet reactions. 相似文献
73.
Communicated by R. B. McFadden 相似文献
74.
Understanding the role of shuttle vibrations in pore fluid distribution is an essential task in the exploration of plant growth
in root modules aboard space flights. Results from experimental investigations are reported in this paper on the distribution
of immiscible fluid phases in glass beads under vibrations. Hexadecane, a petroleum compound immiscible with and lighter than
water, was used in the experiments. The higher freezing point of Hexadecane (18 °C) allowed the solidification of the entrapped
blobs in the presence of water in porous media, so that their size distribution can be obtained. van Genuchten function, commonly
used to express moisture retention curves, is found to be an adequate fit for blob size distribution at residual saturation.
The effect of vibrations on the fate (mobilization, stranding, or breakup) of a solitary ganglion in porous media was studied
using a network model. A mobility criterion considering viscous, gravity, and capillary forces was developed to determine
the fate of a solitary ganglion in a porous medium. It is concluded that the effect of vibrations is to increase the likelihood
of breakup and mobilization of blobs entrapped in porous media at residual saturation. The pore fluid distributions after
vibrations are less uniform than those before vibrations. 相似文献
75.
Nonsteroidal Anti‐inflammatory Drug‐based N‐Allylidene Benzohydrazides and 1‐Acyl‐2‐pyrazolines: Their Synthesis as Potential Cytotoxic Agents In Vitro
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Kavitha Kankanala V. Ranga Reddy Yumnam Priyadarshini Devi Lakshmi Narasu Mangamoori D. Rambabu K. Mukkanti Sarbani Pal 《Journal of heterocyclic chemistry》2015,52(1):105-113
A series of 1‐acyl‐2‐pyrazoline derivatives derived from nonsteroidal anti‐inflammatory drugs was designed as potential anticancer agents. Synthesis of these compounds was carried out via the condensation reaction of chalcones and acid hydrazides under heating. The methodology did not require the use of any costly reagents or catalysts, and the acid hydrazide reactants were readily prepared from mefenamic acid or ibuprofen. A variety of 1‐acyl‐2‐pyrazolines was prepared in good to excellent yields. An N‐allylidene benzohydrazide intermediate was isolated during the reaction optimization study, the structure of which was confirmed unambiguously by X‐ray single crystal data. A range of N‐allylidene benzohydrazides were also prepared in good yields. Some of the compounds synthesized showed promising cytotoxic activities when tested against HCT‐15 human colon cancer cell line in vitro. 相似文献
76.
Russian Journal of General Chemistry - 2-Phenyl-4-{4-[(1-phenyl-1H-1,2,3-triazol-4-yl)methoxy]benzylidene}oxazol-5(4H)-one derivatives were synthesized by click chemistry reactions. Exploration of... 相似文献
77.
Rao K Chodisetti B Gandi S Mangamoori LN Giri A 《Applied biochemistry and biotechnology》2011,165(5-6):1366-1378
Alpinia galanga is a rhizomatous herb rich in essential oils and various other significant phytoconstituents. Rapid direct regeneration was obtained from the rhizome explants (15.66 ± 0.57 shoots) on MS media supplemented with zeatin at a concentration of 2 mg/l. The callus cultures of A. galanga were initiated from the rhizome explants on MS media supplemented with 2 mg/l each of BAP, 2,4-D, and NAA. The callus was analyzed for the presence of a vital phytoconstituent--acetoxychavicol acetate (ACA) associated with various biological properties. ACA was detected in the young friable callus as well as the stationary phase callus. Moreover, the induction of morphogenetic response in callus resulted in higher accumulation of ACA. The phytohormone withdrawal from the propagation media and the subsequent transfer of callus to BAP (2 mg/l) containing MS media has resulted in multiple shoot induction. The regenerated (indirect) plants have shown 1.6-fold higher ACA content (1.253%) when compared to the control plant (0.783%). Micropropagation of such conventionally propagated plants is very essential to meet the commercial demand as well as to ensure easy storage and transportation of disease free stocks. 相似文献
78.
B. Lakshmi Prakash Gouda Avaji K.N. Shivananda Praveen Nagella S.H. Manohar K.N. Mahendra 《Polyhedron》2011,30(9):1357-1515
A series of binuclear Co(II), Ni(II) and Cu(II) complexes were synthesized by the template condensation of glyoxal, biacetyl or benzil bis-hydrazide, 2,6-diformyl-4-methylphenol and Co(II), Ni(II) or Cu(II) chloride in a 2:2:2 M ratio in ethanol. These 22-membered macrocyclic complexes were characterized by elemental analyses, magnetic, molar conductance, spectral, thermal and fluorescence studies. Elemental analyses suggest the complexes have a 2:1 stoichiometry of the type [M2LX2]·nH2O and [Ni2LX22H2O]·nH2O (where M = Co(II) and Cu(II); L = H2L1, H2L2 and H2L3; X = Cl; n = 2). From the spectroscopic and magnetic studies, it has been concluded that the Co(II) and Cu(II) complexes display a five coordinated square pyramidal geometry and the Ni(II) complexes have a six coordinated octahedral geometry. The Schiff bases and their metal complexes have also been screened for their antibacterial and antifungal activities by the MIC method. 相似文献
79.
Koosam Mahendar A. V. S. Sarma P. Raghavaiah Mannepalli Lakshmi Kantam Kenneth J. Klabunde 《Helvetica chimica acta》2011,94(8):1533-1542
Aldol‐type reaction between electron deficient aldehydes and sulfonium salts to afford the corresponding β‐hydroxy α‐sulfanyl esters in moderate‐to‐good yields by using nanocrystalline MgO is described. The sulfanyl group is a useful group for further transformations in organic synthesis. Low Rf‐value isomer is anti‐configured as revealed by X‐ray diffraction study and consistent with the assignment of 1H‐NMR spectrum. 相似文献
80.
John CJ Amalanathan M Sajan D Lakshmi KU Joe IH 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,78(1):264-272
FT-Raman and FT-IR spectra of the nonlinear optical crystal 1-(4-N,N-dimethylaminopyridinium) acetic acid bromide monohydrate have been recorded and analyzed. The equilibrium geometry, vibrational wavenumbers and the first order hyperpolarizability of the crystal have been calculated with the help of density functional theory computations. The assignments of the vibrational spectra have been carried out with the help of Scaled Quantum Mechanic force field theory. Optimized geometry gives the charge transfer interaction of the pyridine ring and the amino group in the electron-donor side of the nonlinear optic chromophore. Electron–phonon coupling and O–H?O interactions in making the molecule nonlinear optical active have been analyzed based on the vibrational spectral features. The Natural Bond Orbital analysis confirms the occurrence of strong intermolecular O–H?O hydrogen bonding. 相似文献