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141.
K. Hegnerová M. Piliarik M. Šteinbachová Z. Flegelová H. Černohorská J. Homola 《Analytical and bioanalytical chemistry》2010,398(5):1963-1966
We present a compact surface plasmon resonance (SPR) biosensor for the detection of bisphenol A (BpA), an endocrine-disrupting
chemical. The biosensor is based on an SPR sensor platform (SPRCD) and the binding inhibition detection format. The detection
of BpA in PBS and wastewater was performed at concentrations ranging from 0.05 to 1,000 ng/ml. The limit of detection for
BpA in PBS and wastewater was estimated to be 0.08 and 0.14 ng/ml, respectively. It was also demonstrated that the biosensor
can be regenerated for repeated use. Results achieved with the SPR biosensor are compared with those obtained using ELISA
and HPLC methods. 相似文献
142.
Nives Škrlj Vladka Čurin Šerbec Marko Dolinar 《Applied biochemistry and biotechnology》2010,160(6):1808-1821
Prion diseases are incurable neurodegenerative diseases that affect both humans and animals. The infectious agent is a pathogenic
form of the prion protein that accumulates in brain as amyloids. Currently, there is neither cure nor reliable preclinical
diagnostics on the market available. The growing number of reports shows that passive immunisation is one of the most promising
strategies for prion disease therapy, where antibodies against prions may prevent and even cure the infection. Since antibodies
are large molecules and, thus, might not be suitable for the therapy, different antibody fragments are a good alternative.
Therefore, we have designed and prepared single-chain antibody fragments (scFvs) derived from the PrPSc-specific murine monoclonal antibody V5B2. Using a new expression vector pMD204, we produced scFvs in two opposing chain orientations
in the periplasm of Escherichia coli. Both recombinant antibody fragments retained the specificity of the parent antibody and one of these exhibited binding properties
comparable to the corresponding murine Fab fragments with the affinity in nM range. Our monovalent antibody fragments are
of special interest in view of possible therapeutic reagents for prion diseases as well as for development of a new generation
of diagnostics. 相似文献
143.
Nikica Šprem Ivan Babić Domagoj Barišić Delko Barišić 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(1):513-517
The aim of this study was to investigate 137Cs and 40K load in large mammal game species in the mountain forest region of Gorski Kotar in Croatia approximately a quarter of century after the Chernobyl accident. 137Cs and 40K activity were determined by the gamma-spectrometric method in 49 meat samples of five large game species: brown bear (Ursus arctos), wild boar (Sus scrofa), roe deer (Capreolus capreolus), red deer (Cervus elaphus), and chamois (Rupicapra rupicapra). The results indicated that herbivore game species (roe deer, red deer and chamois) show significantly lower 137Cs concentrations than omnivore species (brown bear, wild boar), thereby confirming the hypothesis that different dietary strategy impact caesium concentrations in meat. The measured caesium load in brown bear meat was in the range of two orders of magnitude, while caesium load in wild boar meat was found in the range of one order of magnitude. The estimated effective equivalent dose showed that uptake of the highest caesium doses would be from consumption of omnivore species meat, while much lower doses could be taken in with the consumption of meat from herbivore species. 相似文献
144.
Iva Movre Šapić Vesna Volovšek Krešimir Furić Lahorija Bistričić Vladimir Dananić 《Macromolecular Symposia》2011,305(1):122-125
In this work we investigated the solidification of aminopropylsilanetriol dissolved in water (∼25%) under different conditions by Raman spectroscopy. The solidification was carried out at three different temperatures 8 °C, 23 °C and 60 °C. The influence of electromagnetic radiation on the polymerization process was also studied. Samples were held to solidify in dark and at UV (254 nm and 356nm) spectral range. In order to investigate the influence of the substrate on the resulting polymer structure, teflon, PVC, glass, brass and silica were used. Best ordered polymerized structure was achieved for samples deposited on plastics and solidified in dark, at room temperature. 相似文献
145.
L. Kosta V. Ravnik A. R. Byrne J. Štirn M. Dermelj P. Stegnar 《Journal of Radioanalytical and Nuclear Chemistry》1978,44(2):317-332
A number of investigations of trace elements in the waters, organisms and sediments of the Adriatic, using neutron activation
analysis with radiochemical, separations are reported. These include studies of Hg in mussels from the Northern Adriatic,
of Hg and Se in edible animals from the Rijeka region, and of seven elements (As, Cd, Cu, Hg, Mn, Se and Zn) in marine invertebrates
from the Slovene coast. Additionally, plankton, sediment cores and water samples were taken from a grid of stations covering
the whole Adriatic and analyzed for 6 to 11 of the trace elements As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Sb and Zn (Hg only in water).
Generally, levels found were not indicative of pollution as compared with oceanic samples, but some evidence of locally increased
levels was found, especially for Hg. The levels of eleven trace elements in three marine Intercomparison samples prepared
by the IAEA Monaco Laboratory are also presented. 相似文献
146.
F. Šebesta 《Journal of Radioanalytical and Nuclear Chemistry》1970,6(1):41-46
The extraction-chromatographic behaviour of zinc on a column with dithizone as chelating agent has been investigated in the
absence and presence of oxalic acid as masking agent. From the results the extraction constant and the stability constants
of zinc oxalate complexes have been determined. These values are in good agreement with the published data so that it seems
possible to predict the extraction-chromatographic separation of various metals from known extraction and stability constants. 相似文献
147.
148.
Samples of poly(12-dodecanelactam) (polylaurolactam, nylon 12) with n 1 × 103?33 × 103 were prepared. Polymerizations initiated with water or with lauric acid proceeded under conditions for minimum changes in end-group concentration. Values of n were calculated from the end-group content and n from light scattering in the mixture m-cresol/60 vol% of 2.2,3,3-tetrafluoropropanol. From measurements of intrinsic viscosity in m-cresol, the relationship [n] ? n was established in the given range of n. The relationship [n] ? w for w from 3.3 × 103 to 125 × 103 has been established. 相似文献
149.
The influence of different modes of preparation on the stoichiometry of thermal decomposition of isothiocyanatonickel(II) complexes with ammonia was studied. It was found that the complex Ni(NCS)2(NH3)4 (I) prepared by heterogeneous reaction undergoes decomposition in two steps (–2 NH3, –2 NH3), while for complex II, of the same composition but prepared by homogeneous reaction from solution, the decomposition proceeds in three steps (–1 NH3, –1 NH3, –2NH3). Electronic and infrared absorption spectra were used for the study of the spectral properties of the starting complex. It was found that the different stoichiometries of thermal decompositions of complexes I and II do not cause differences in the bonding strength of the ammonia molecules (chemical factor); this effect is rather brought about by physical factors such as different imperfections of the crystal lattice.
Zusammenfassung Der Einfluß der Herstellung auf die Stöchiometrie der thermischen Zersetzung von Amin-Komplexen des Isothiocyanatonickels wurde studiert. Der Zerfall des Komplexes Ni(NCS)2(NH3)4 (I), hergestellt durch heterogene Reaktion, verlief in zwei Etappen (–2 NH3, –2 NH3). Beim selben Komplex (II), hergestellt durch homogene Reaktion in Lösung, wurden jedoch drei Etappen beobachtet (–1 NH3, –1 NH3, –2 NH3). Die Eigenschaften des Ausgangsproduktes wurden durch Elektronen- und IR-Spektroskopie untersucht. Das unterschiedliche thermische Verhalten ist nicht auf eine verschiedene Bindungsstärke der NH3 Moleküle, sondern auf physikalische Ursachen, wie z. B. Unregelmässigkeiten im Kristallgitter zurückzuführen.
Résumé On a étudié l'influence des diverses méthodes de préparation sur la stoechiométrie de la réaction de décomposition thermique des complexes de l'isothiocyanate de nickel(II) avec l'ammoniac. On a établi que le complexe Ni(SCN)2(NH3)4, (I), préparé rar réaction hétérogène, subit une décomposition en deux étapes (–2NH3, –2NH3), tandis que le complexe (II), de même composition, mais préparé par réaction homogène, à partir de solutions, se décompose en trois étapes (–1NH3,–1NH3, –2NH3). Les propriétés spectrales du complexe initial ont été étudiées par absorption électronique et infrarouge. On a trouvé que les différences de stoechiométrie des réactions de décomposition thermique des complexes (I) et (II) n'apportaient pas de différences entre les énergies de liaison des molécules d'ammoniac (facteur chimique). C'est plutôt à des facteurs physiques, comme les différentes imperfections du réseau cristallin, que cet effet serait dû.
(II) . , Ni(NCS)2(NH3)4 (I), , (–2NH3,–2NH3). , II , , (–1 NH3,–1 NH3 –2NH3). . , I II ( ), , .相似文献
150.
Dynamic light scattering spectroscopy has been used to determine the temperature dependence of the anchoring strength of the nematic liquid crystal 8OCB on DMOAP‐silanated glass surfaces inducing homeotropic alignment. Wedge‐type glass cells with known thickness profile starting from 150 nm to several microns have been used in the experiments. The relaxation rates of the nematic fluctuations with the wave vector perpendicular to the confining surfaces have been measured as a function of the cell thickness. Fitting of the thickness dependence of the relaxation rate allows for straightforward determination of the surface extrapolation length and therefore also the strength of the surface anchoring, which is 1×10?4 J m?2. The overall experimental accuracy of the experiments is discussed. 相似文献