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161.
Brooke E. Crowley Claudia Wultsch Marcella J. Kelly 《Isotopes in environmental and health studies》2013,49(5):478-498
ABSTRACTFaecal isotopic analysis may complement other non-invasive wildlife survey tools for monitoring landscape use by carnivores, such as motion-detecting cameras and non-invasive genetic sampling. We analysed carbon, nitrogen, and strontium isotopes in faecal matter produced by jaguars (Panthera onca) as well as bones from consumed prey at the Mountain Pine Ridge Forest Reserve (MPR) in Belize, Central America. The MPR is ideally suited for a spatial isotope study as vegetation and geology both vary considerably. The isotopic composition of faecal matter should reflect the habitat and geology where consumed prey lived. We used bone from consumed prey recovered from jaguar scats as a proxy for diet. Faecal matter and bone showed comparable spatial isotopic trends, suggesting that the isotopic composition of jaguar faeces can be used to detect foraging in different habitats (pine forest versus broadleaf forest) or on different geologies (Mesozoic carbonates; Palaeozoic granite, contact metamorphics, and metasediments). This result is reassuring as bones are not always present in carnivore scats. Studying landscape use by cryptic and wide-ranging carnivore species like jaguars remains challenging. Isotopic analysis of faecal matter complements the existing array of non-invasive spatial monitoring tools. 相似文献
162.
Berardi S La Ganga G Natali M Bazzan I Puntoriero F Sartorel A Scandola F Campagna S Bonchio M 《Journal of the American Chemical Society》2012,134(27):11104-11107
Isostructural cubane-shaped catalysts [Co(III)(4)(μ-O)(4)(μ-CH(3)COO)(4)(p-NC(5)H(4)X)(4)], 1-X (X = H, Me, t-Bu, OMe, Br, COOMe, CN), enable water oxidation under dark and illuminated conditions, where the primary step of photoinduced electron transfer obeys to Hammett linear free energy relationship behavior. Ligand design and catalyst optimization are instrumental for sustained O(2) productivity with quantum efficiency up to 80% at λ > 400 nm, thus opening a new perspective for in vitro molecular photosynthesis. 相似文献
163.
Busto N García B Leal JM Secco F Venturini M 《Organic & biomolecular chemistry》2012,10(13):2594-2602
A thermodynamic and kinetic study on the mode of binding of 9-amino-6-chloro-2-methoxi-acridine (ACMA) to poly(dA-dT)·poly(dA-dT) and poly(dG-dC)·poly(dG-dC) has been undertaken at pH = 7.0 and I = 0.1 M. The spectrophotometric, kinetic (T-jump), circular dichroism, viscometric and calorimetric information gathered point to formation of a fully intercalated ACMA complex with poly(dA-dT)·poly(dA-dT) and another one only partially intercalated (7%) with poly(dG-dC)·poly(dG-dC). The ACMA affinity with the A-T bases was higher than with the G-C bases. The two polynucleotide sequences give rise to external complexes when the ACMA concentration is raised, namely, the electrostatic complex poly(dA-dT)·poly(dA-dT)-ACMA and the major groove binding complex poly(dG-dC)·poly(dG-dC)-ACMA. A considerable quenching effect of the ACMA fluorescence is observed with poly(dA-dT)·poly(dA-dT), ascribable to face-to-face location in the intercalated A-T-ACMA base-pairs. The even stronger effect observed in the presence of poly(dG-dC)·poly(dG-dC) is related to the guanine residue from on- and off-slot ACMA positions. 相似文献
164.
165.
Valore A Balordi M Colombo A Dragonetti C Righetto S Roberto D Ugo R Benincori T Rampinini G Sannicolò F Demartin F 《Dalton transactions (Cambridge, England : 2003)》2010,39(42):10314-10318
Various Ru(II) complexes with substituted 1,10-phenanthroline or 4,5-diazafluorene are characterized by a good to very large second order NLO response, as determined by EFISH. Among these complexes, [Ru(9-fulleriden-4,5-diazafluorene)(PPh(3))(2)Cl(2)] is particularly appealing due to its huge second-order NLO response and its transparency to the second harmonic generation. The structure of cis-Cl,trans-PPh(3)-[Ru(5-NO(2)-1,10-phen)(PPh(3))(2)Cl(2))] was determined by single-crystal X-ray diffraction. 相似文献
166.
Marina Cretich Daniela Breda Francesco Damin Marta Borghi Laura Sola Selim M. Unlu Samuele E. Burastero Marcella Chiari 《Analytical and bioanalytical chemistry》2010,398(4):1723-1733
We have recently introduced a silicon substrate for high-sensitivity microarrays, coated with a functional polymer named copoly(DMA-NAS-MAPS).
The silicon dioxide thickness has been optimized to produce a fluorescence intensification due to the optical constructive
interference between the incident and reflected lights of the fluorescent radiation. The polymeric coating efficiently suppresses
aspecific interaction, making the low background a distinctive feature of these slides. Here, we used the new silicon microarray
substrate for allergy diagnosis, in the detection of specific IgE in serum samples of subjects with sensitizations to inhalant
allergens. We compared the performance of silicon versus glass substrates. Reproducibility data were measured. Moreover, receiver-operating
characteristic (ROC) curves were plotted to discriminate between the allergy and no allergy status in 30 well-characterized
serum samples. We found that reproducibility of the microarray on glass supports was not different from available data on
allergen arrays, whereas the reproducibility on the silicon substrate was consistently better than on glass. Moreover, silicon
significantly enhanced the performance of the allergen microarray as compared to glass in accurately identifying allergic
patients spanning a wide range of specific IgE titers to the considered allergens. 相似文献
167.
Edith Joseph Silvia Prati Giorgia Sciutto Marcella Ioele Paola Santopadre Rocco Mazzeo 《Analytical and bioanalytical chemistry》2010,396(2):899-910
Different Fourier transform infrared microspectroscopic techniques, using attenuated total reflection (ATR) mode and single-element
mercury–cadmium–telluride (MCT) detector (mapping) or multielement MCT detector (raster scanning), are compared with each
other for the characterisation of inorganic compounds and organic substances in paint cross sections. All measurements have
been performed on paint cross sections embedded in potassium bromide, a transparent salt in the mid-infrared region, in order
to better identify the organic materials without the interference of the usual embedding resin. The limitations and advantages
of the different techniques are presented in terms of spatial resolution, data quality and chemical information achieved.
For all techniques, the chemical information obtained is found to be nearly identical. However, ATR mapping performed with
a recently developed instrumentation shows the best results in terms of spectral quality and spatial resolution. In fact,
thin organic layers (∼10 μm) have been not only identified but also accurately located. This paper also highlights the recent
introduction of multielement detectors, which may represent a good compromise between mapping and imaging systems. 相似文献
168.
Marcella P. Felicissimo José Luis S. Peixoto Roberto Tomasi Ammar Azioune Jean-Jacques Pireaux Laurent Houssiau 《哲学杂志》2013,93(32):3483-3496
X-ray photoemission spectroscopy (XPS) and time-of-flight (TOF) secondary-ion mass spectroscopy (SIMS) have been applied to investigate potsherd samples from Pantanal, Brazil. One of the potsherds presented burnt bone as an additive, which was characterized by XPS as carbonate hydroxyapatite. For shell-tempered ceramics the phase present in shells after firing was identified by X-ray diffraction. TOF-SIMS was used to study the distribution of quartz as temper in one of the sherds. XPS was also applied to the characterization of the finishing external layer of the ceramic vessels. In this case, based on the Fe 2p spectra of the sherd's interior and outermost layers, it was possible to prove that their difference in coloration is due to black heart formation. Hierarchical clustering analysis and principal component analysis of the XPS elemental data enabled the potsherds to be classified with respect to their clay composition. 相似文献
169.
170.
Charles A. Homsy Krystyna D. Ansevin William O'bannon Sara A. Thompson Roosevelt Hodge Marcella E. Estrella 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(3):615-634
A rapid in vitro screening protocol to guide selection and monitoring of polymers for implant or extracorporeal applications is described. There are four main procedures under the protocol: 1) and 2) measurement of physical property change over thermal and simulated biochemical stress, 3) infrared spectrophotometric assay of migratible species developed over simulated biochemical stress, and 4) cell culture sensitivity to those migratible species. In vivo biochemical stress was simulated and accelerated by exposing polymer specimens to a pseudoextracellular fluid (PECF) at 120°C for 62 hr. Results from procedures 3) and 4) are presented. These show a good correlation between cell culture response and the total carbon-hydrogen bonds developed in the PSF over the exposure period. Correlation of these data with available clinical and animal implant experience is consistent and is discussed in detail. Infrared assays for a candidate polymer may be obtained at relatively low cost within 4 days and stand as a rational basis for rejection or retention for preclinical in vivo studies. 相似文献