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21.
Ahmad Arouri Anders Højgaard Hansen Thomas Elmelund Rasmussen Ole G. Mouritsen 《Current Opinion in Colloid & Interface Science》2013,18(5):419-431
Colloidal and interfacial phenomena lie at the core of drug formulation, drug delivery, as well as drug binding and action at diseased sites, e.g., in cancer therapy. We review a class of liposome-based drug-delivery systems whose design and functional properties are intimately controlled by the stability of sub-micron structures, lipid-bilayer interfaces, and interfacially activated enzymes that can be exploited to target and deliver drugs. Moreover these drugs can themselves be special lipid molecules in the form of lipid prodrugs that both form the liposomal carrier as well as the substrate for endogenously upregulated lipases that turn the prodrugs into potent drugs precisely at the diseased site. 相似文献
22.
SPE HG-AAS method for the determination of inorganic arsenic in rice—results from method validation studies and a survey on rice products 总被引:1,自引:0,他引:1
Rie R. Rasmussen Yiting Qian Jens J. Sloth 《Analytical and bioanalytical chemistry》2013,405(24):7851-7857
The present paper describes the development, validation and application of a method for inorganic arsenic (iAs) determination in rice samples. The separation of iAs from organoarsenic compounds was done by off-line solid-phase extraction (SPE) followed by hydride generation atomic absorption spectrometry (HG-AAS) detection. This approach was earlier developed for seafood samples (Rasmussen et al., Anal Bioanal Chem 403:2825–2834, 2012) and has in the present work been tailored for rice products and further optimised for a higher sample throughput and a lower detection limit. Water bath heating (90 °C, 60 min) of samples with dilute HNO3 and H2O2 solubilised and oxidised all iAs to arsenate (AsV). Loading of buffered sample extracts (pH 6?±?1) followed by selective elution of arsenate from a strong anion exchange SPE cartridge enabled the selective iAs quantification by HG-AAS, measuring total arsenic (As) in the SPE eluate. The in-house validation gave mean recoveries of 101–106 % for spiked rice samples and in two reference samples. The limit of detection was 0.02 mg kg?1, and repeatability and intra-laboratory reproducibility were less than 6 and 9 %, respectively. The SPE HG-AAS method produced similar results compared to parallel high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (ICP-MS) analysis. The SPE separation step was tested collaboratively, where the laboratories (N?=?10) used either HG-AAS or ICP-MS for iAs determination in a wholemeal rice powder. The trial gave satisfactory results (HorRat value of 1.6) and did not reveal significant difference (t test, p?>?0.05) between HG-AAS and ICP-MS quantification. The iAs concentration in 36 rice samples purchased on the Danish retail market varied (0.03–0.60 mg kg?1), with the highest concentration found in a red rice sample. 相似文献
23.
Prof. Pil Seok Chae Andrew C. Kruse Dr. Kamil Gotfryd Rohini R. Rana Kyung Ho Cho Prof. Søren G. F. Rasmussen Hyoung Eun Bae Richa Chandra Prof. Ulrik Gether Prof. Lan Guan Prof. Brian K. Kobilka Prof. Claus J. Loland Dr. Bernadette Byrne Prof. Samuel H. Gellman 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(46):15645-15651
Integral membrane proteins play central roles in controlling the flow of information and molecules across membranes. Our understanding of membrane protein structures and functions, however, is seriously limited, mainly due to difficulties in handling and analysing these proteins in aqueous solution. The use of a detergent or other amphipathic agents is required to overcome the intrinsic incompatibility between the large lipophilic surfaces displayed by the membrane proteins in their native forms and the polar solvent molecules. Here, we introduce new tripod amphiphiles displaying favourable behaviours toward several membrane protein systems, leading to an enhanced protein solubilisation and stabilisation compared to both conventional detergents and previously described tripod amphiphiles. 相似文献
24.
Prof. Pil Seok Chae Prof. Søren G. F. Rasmussen Rohini R. Rana Kamil Gotfryd Andrew C. Kruse Aashish Manglik Kyung Ho Cho Shailika Nurva Prof. Ulrik Gether Prof. Lan Guan Prof. Claus J. Loland Dr. Bernadette Byrne Prof. Brian K. Kobilka Prof. Samuel H. Gellman 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(16):4964-4964
25.
Reka Geczy Niels Johan Christensen Kim K. Rasmussen Ildik Klomista Manish K. Tiwari Pratik Shah Seong Wook Yang Morten J. Bjerrum Peter W. Thulstrup 《Angewandte Chemie (International ed. in English)》2020,59(37):16091-16097
Fluorescent, DNA‐stabilized silver nanoclusters (DNA‐AgNCs) are applied in a range of applications within nanoscience and nanotechnology. However, their diverse optical properties, mechanism of formation, and aspects of their composition remain unexplored, making the rational design of nanocluster probes challenging. Herein, a synthetic procedure is described for obtaining a high yield of emissive DNA‐AgNCs with a C‐loop hairpin DNA sequence, with subsequent purification by size‐exclusion chromatography (SEC). Through a combination of optical spectroscopy, gel electrophoresis, inductively coupled plasma mass spectrometry (ICP‐MS), and small‐angle X‐ray scattering (SAXS) in conjunction with the systematic study of various DNA sequences, the low‐resolution structure and mechanism of the formation of AgNCs were investigated. Data indicate that fluorescent DNA‐AgNCs self‐assemble by a head‐to‐head binding of two DNA hairpins, bridged by a silver nanocluster, resulting in the modelling of a dimeric structure harboring an Ag12 cluster. 相似文献
26.
Concentrations of rare earth elements in sediments,mussels and fish from a Danish marine environment,Lillebaelt 总被引:1,自引:0,他引:1
I. Drabaek P. Eichner L. Rasmussen 《Journal of Radioanalytical and Nuclear Chemistry》1987,114(1):29-38
Results for the content of the rare earth elements (REE), La, Ce, Nd, Sm, Eu, Tb, Yb and Lu in sediments, mussels and fish are presented for an area polluted by REE. The REE are emitted with the process waste water stream from a fertilizer production plant. The method of analysis has been INAA. An attempt to combine the INAA with a simple destruction/preconcentration method is described. 相似文献
27.
28.
E. F. Jones P. M. Gore J. H. Hamilton A. V. Ramayya A. P. de Lima R. S. Dodder J. Kormicki J. K. Hwang C. J. Beyer X. Q. Zhang S. J. Zhu G. M. Ter-Akopian Yu. Ts. Oganessian A. V. Daniel J. O. Rasmussen I. Y. Lee J. D. Cole M. W. Drigert W.-C. Ma 《Physics of Atomic Nuclei》2001,64(7):1157-1164
The levels in 162Gd were identified in spontaneous fission studies. Its transition energies are remarkably similar to those in 160Gd. From that work, an analysis of yrast bands in even-even proton to neutron-rich Ba to Pb nuclei led to the discovery of a new phenomenon, shifted identical bands (SIB). SIBs are yrast bands in neighboring nuclei (a, b) with moments of inertia which are identical when shifted by a constant amount κ, so J 1a (1+κ)=J 1b , from 2+ to 8+ and higher to 16+. Out of over 700 comparisons, 55 SIBs were found from stable to the most neutron-rich Ce-W nuclei with $\left| {\bar k} \right|$ between 1.5% and 13%, where the spread in κ is less than ±1%, and only four identical bands ( $\bar k \cong 0$ ). As examples, we found for 158Sm-160Gd, $\bar k = \left( { - 3.2_{ - 0.2}^{ + 0.1} } \right)\%$ (where the ± is the total spread in κ from ?3.1 to ?3.4); 156Nd-160Gd, (?10.6 ?0.2 +0.4 )%; 158Sm-160Sm, (3.4 ?0.3 +0.5 )%. The J 1 values were fitted to a variable moment of inertia model with parameters J 0 and C whose values correlate with the SIB J 1 values. The SIBs are not correlated either with deformation or with the N p N n product of the IBA model. 相似文献
29.
E. F. Jones P. M. Gore S. J. Zhu J. H. Hamilton A. V. Ramayya J. K. Hwang R. Q. Xu L. M. Yang K. Li Z. Jiang Z. Zhang S. D. Xiao X. Q. Zhang W. C. Ma J. D. Cole M. W. Drigert I. Y. Lee J. O. Rasmussen Y. X. Luo M. A. Stoyer 《Physics of Atomic Nuclei》2006,69(7):1198-1203
We have used our analysis of γ-γ-γ data (5.7 × 1011 triples and higher folds) taken with Gammasphere from prompt γ rays emitted in the spontaneous fission of 252Cf to study the collective bands in 104,106,108Mo. The one-phonon and two-phonon γ-vibrational bands and known two-quasiparticle bands in neutron-rich 104,106Mo were extended to higher spins. The one-and two-phonon γ-vibrational bands have remarkably close energies for transitions from the same spin states and identical moments of inertia.
Several new bands are observed and are proposed as quasiparticle bands in 104,106Mo, along with the first β-type vibrational band in 106Mo. The quasiparticle bands have essentially constant moments of inertia near the rigid-body value that indicate blocking
of the pairing interaction. Candidates for chiral doublet bands in 106Mo are strong. These are the first reported chiral vibrational bands in an even-even nucleus.
The text was submitted by the authors in English. 相似文献
30.
Ebbe Rasmussen 《Zeitschrift für Physik A Hadrons and Nuclei》1932,73(11-12):779-790