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151.
In recent years, near-infrared spectroscopy (NIRS) has gained importance for non-invasive or minimally invasive diagnostic
applications in cancer. This technology is based on differences of endogenous chromophores between cancer and normal tissues
using either oxy-haemoglobin or deoxy-haemoglobin, lipid or water bands, or a combination of two or more of these as diagnostic
markers. These marker bands provide a basis for the diagnosis and therapy monitoring of several cancers. Various applications
also use advances in NIR fluorescence spectroscopy which is based on exogenous contrast-enhancing agents. In this review the
literature published during the last seven years has been assessed. It will provide an overview on the importance of the NIRS
tools in cancer pathology, and in the near future it is envisaged to play a crucial role in cancer diagnosis, treatment decisions,
and defining therapeutic drug levels. 相似文献
152.
Prasad Mishra G Venkata Ramana G Venkateswara Rao B 《Chemical communications (Cambridge, England)》2008,(29):3423-3425
A new, efficient and highly diastereoselective approach for the synthesis of 1,2,3,5-tetraacetylcarba-alpha-D-lyxofuranose from D-ribose is reported via one-pot conversion of to using Tebbe reagent which involves a cascade reaction sequence of methylenation, cleavage of isopropyl group, carbocyclization and again methylenation. 相似文献
153.
Venkatapuram Padmavathi Annaji Venkata Nagendra Mohan Konda Mahesh 《Journal of heterocyclic chemistry》2008,45(4):1131-1138
154.
Venkatapuram Padmavathi Kaveti Sudheer Dandu Rangayapalle Chinna Venkata Subbaiah Konda Mahesh 《Journal of heterocyclic chemistry》2008,45(2):513-519
155.
Mudiganti NV Claessens S Habonimana P De Kimpe N 《The Journal of organic chemistry》2008,73(10):3867-3874
An efficient synthesis of naturally occurring compounds isolated from Pentas longiflora, cis-3,4-dihydroxy-3,4-dihydromollugin 2, and trans-3,4-dihydroxy-3,4-dihydromollugin 3 is described. The O-protected mollugins were dihydroxylated using OsO4 to achieve the corresponding cis-dihydroxy derivatives in excellent yield. The synthesis of trans-3,4-dihydroxy-3,4-dihydromollugin was achieved using Oxone in good yield. A mechanism for the formation of cis-3,4-dihydroxymollugin acetonide from the reaction of mollugin with Oxone is proposed. 相似文献
156.
Electrospinning is a well-known technique since 1544 to fabricate nanofibers using different materials like polymers, metals oxides, proteins, and many more. In recent years, electrospinning has become the most popular technique for manufacturing nanofibers due to its ease of use and economic viability. Nanofibers have remarkable properties like high surface-to-volume ratio, variable pore size distribution (10–100 nm), high porosity, low density, and are suitable for surface functionalization. Therefore, electrospun nanofibers have been utilized for numerous applications in the pharmaceutical and biomedical field like tissue engineering, scaffolds, grafts, drug delivery, and so on. In this review article, we will be focusing on the versatility, current scenario, and future endeavors of electrospun nanofibers for various biomedical applications. This review discusses the properties of nanofibers, the background of the electrospinning technique, and its emergence in chronological order. It also covers the various types of electrospinning methods and their mechanism, further elaborating the factors affecting the properties of nanofibers, and applications in tissue engineering, drug delivery, nanofibers as biosensor, skin cancer treatment, and magnetic nanofibers. 相似文献
157.
Spectroscopic investigation of a dihydrogen-bonded complex between phenol and triethylgermanium hydride is reported here. Laser-induced fluorescence excitation, fluorescence-detected infrared, and IR-UV hole-burning spectroscopic studies were carried out in supersonic jet to investigate the complex formation between phenol and triethylgermanium hydride. The lowering of the O-H stretching frequency of the phenol moiety in the complex with triethylgermanium hydride clearly establishes the role of phenol as hydrogen bond donor. The experimental results together with the ab-initio calculations unambiguously confirm formation of an O-H...H-Ge dihydrogen-bonded complex between phenol and triethylgermanium hydride. 相似文献
158.
The electronic transitions of phenylacetylene complexes with water and trifluoroethanol are shifted to the blue, while the corresponding transitions for methanol and ethanol complexes are shifted to the red relative to the phenylacetylene monomer. Fluorescence dip infrared (FDIR) spectra in the O-H stretching region indicate that, in all the cases, phenylacetylene is acting as a hydrogen bond acceptor to the alcohols. The FDIR spectrum in the acetylenic C-H stretching region shows Fermi resonance bands for the bare phenylacetylene, which act as a sensitive tool to probe the intermolecular structures. The FDIR spectra reveal that water and trifluoroethanol interact with the pi electron density of the acetylene C-C triple bond, while methanol and ethanol interact with the pi electron density of the benzene ring. It can be inferred that the hydrogen bonding acceptor site on phenylacetylene switches from the acetylene pi to the benzene pi with lowering in the partial charge on the hydrogen atom of the OH group. The most significant finding is that the intermolecular structures of water and methanol complexes are notably distinct, which, to the best of our knowledge, this is first such observation in the case of complexes of substituted benzenes. 相似文献
159.
Valeriu Mereacre Denis Prodius Ayuk M. Ako Narpinder Kaur Janusz Lipkowski Charles Simmons Naresh Dalal Ion Geru Christopher E. Anson Annie K. Powell Constantin Turta 《Polyhedron》2008
Reaction of manganese acetate and lanthanide nitrates in the presence of excess of PhCOOH affords highly asymmetric dodecanuclear mixed-metal [Mn10Ln2(OH)(O)8(PhCOOH)(PhCOO)19] (Ln = PrIII (1), NdIII (2)) clusters. The similar reaction, but with only 2 equiv. of PhCOOH resulted in the compounds with higher nuclearity [Mn11Eu4(O)8(OH)8(PhCOO)18(NO3)2(H2O)6]NO3 · 4CH3CN (3). Variable-temperature solid-state magnetic susceptibility of 1 and 2 in the temperature range 1.8–300 K were carried out, and for both complexes antiferromagnetic exchange interactions between the metal centers were observed, giving an estimated S = 17/2 ground state. AC magnetic susceptibility data have revealed out-of-phase signals, which suggest that these complexes exhibit a slow relaxation of magnetization as observed in single-molecule magnets. 相似文献
160.
Vydyula Pavan Kumar Iragavarapu Suryanarayana Yadavalli Venkata Durga Nageswar Kakulapati Rama Rao 《Helvetica chimica acta》2008,91(4):753-758
Two modified β‐cyclodextrins, H‐2 and H‐3 , having a flexible appended moiety were studied for the chiral discrimination of the enantiomers of various amino acids by means of fluorescence as signaling option. These hosts quenched the fluorescence intensities of amino acids upon binding. The d‐ enantiomers were better recognized by these hosts. The association constants (Ks) and enantioselectivity factors (α) of the host?guest complexes were calculated. 相似文献