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61.
62.
63.
T. Arnold A. Barbour S. Chanaa R. E. Cook D. Fernandez-Canato P. Landry T. Seydel P. Yaron J. Z. Larese 《The European physical journal. Special topics》2009,167(1):143-150
Recent incoherent neutron scattering investigations of the dynamics of thin
alkane films adsorbed on the Magnesium Oxide (100) surface are reported.
There are marked differences in the behaviour of these films, as a function
of temperature and coverage, compared to similar measurements on graphite.
In particular, it has previously been shown that adsorbed multilayer films
on graphite exhibit an interfacial solid monolayer that coexists with
bulk-like liquid, well above the bulk melting point. In contrast, these
studies show that the alkane films on MgO exhibit no such stabilization of
the solid layer closest to the substrate as a function of the film
thickness, even though the monolayer crystal structures are remarkably
similar. These studies are supported by extensive thermodynamic data, a
growing body of structural data from neutron diffraction and state of the
art computer modelling 相似文献
64.
Naiyu Zheng Jianing Zeng Qin C. Ji Aida Angeles Anne-Francoise Aubry Shenita Basdeo Adela Buzescu Ishani Savant Landry Navin Jariwala Wesley Turley Richard Burrell Mark E. Arnold 《Analytica chimica acta》2016
Dried saliva spot (DSS) sampling is a non-invasive sample collection technique for bioanalysis that can be potentially implemented at the patient's home. A UHPLC-MS/MS assay was developed using detergent-assisted sample extraction to quantify BMS-927711, a drug candidate in development for the treatment of migraines, in human DSS. By implementing DSS sampling at the patients' home, the bioanalytical sample collection for pharmacokinetic evaluation can be done at the time of the acute migraine attack without the need for clinical visits. DSS samples were prepared by spotting 15 μL of liquid saliva onto regular Whatman FTA™ DMPK-C cards and verified with a UV lamp (at λ 254 nm or 365 nm) during DSS punching. The 4-mm DSS punches in a 96-well plate were sonicated with 200 μL of [13C2, D4]-BMS-927711 internal standard (IS) solution in 20/80 MeOH/water for 10 min, followed by sonication with 50 μL of 100 mM NH4OAc with 1.0% Triton-X-100 (as detergent) prior to liquid-liquid extraction with 600 μL EtOAc/Hexane (90:10). UHPLC-MS/MS was performed with an Aquity® UPLC BEH C18 Column (2.1 × 50 mm, 1.7 μm) on a Triple Quad™ 5500 mass spectrometer. The assay was linear with a concentration range from 2.00 to 1000 ng mL−1 for BMS-927711 in human saliva. The intra- and inter-assay precision was within 8.8% CV, and the accuracy was within ±6.7% Dev of the nominal concentration values. This UHPLC–MS/MS assay has been successfully applied to determine the drug's pharmacokinetics within a clinical study. For the first time, we observed BMS-927711 exposure in human DSS, confirming the suitability of this sampling technique for migraine patients to use at home. Detergent-assisted extraction with Triton-X-100 could be very useful in DSS or other dried matrix spot (DMS) assays to overcome low or inconsistent analyte recovery issues. 相似文献
65.
Duncan AK Klemm PJ Raymond KN Landry CC 《Journal of the American Chemical Society》2012,134(19):8046-8049
Particle-based magnetic resonance imaging (MRI) contrast agents have been the focus of recent studies, primarily due to the possibility of preparing multimodal particles capable of simultaneously targeting, imaging, and treating specific biological tissues in vivo. In addition, particle-based MRI contrast agents often have greater sensitivity than commercially available, soluble agents due to decreased molecular tumbling rates following surface immobilization, leading to increased relaxivities. Mesoporous silica particles are particularly attractive substrates due to their large internal surface areas. In this study, we immobilized a unique phosphonate-containing ligand onto mesoporous silica particles with a range of pore diameters, pore volumes, and surface areas, and Gd(III) ions were then chelated to the particles. Per-Gd(III) ionic relaxivities ranged from ~2 to 10 mM(-1) s(-1) (37 °C, 60 MHz), compared to 3.0-3.5 mM(-1) s(-1) for commercial agents. The large surface areas allowed many Gd(III) ions to be chelated, leading to per-particle relaxivities of 3.3 × 10(7) mM(-1) s(-1), which is the largest value measured for a biologically suitable particle. 相似文献
66.
A. Caboussat C. Landry J. Rappaz 《Journal of Optimization Theory and Applications》2010,147(1):141-156
The numerical analysis of a dynamic constrained optimization problem is presented. It consists of a global minimization problem
that is coupled with a system of ordinary differential equations. The activation and the deactivation of inequality constraints
induce discontinuity points in the time evolution. A numerical method based on an operator splitting scheme and a fixed point
algorithm is advocated. The ordinary differential equations are approximated by the Crank-Nicolson scheme, while a primal-dual
interior-point method with warm-starts is used to solve the minimization problem. The computation of the discontinuity points
is based on geometric arguments, extrapolation polynomials and sensitivity analysis. Second order convergence of the method
is proved when an inequality constraint is activated. Numerical results for atmospheric particles confirm the theoretical
investigations. 相似文献
67.
Fe(III) undergoes a reaction with colourless Ru(CN)(4-)(6) to produce an intensely violet-blue complex that absorbs at 550 nm and obeys Beer's law over the iron concentration range 0.04-2 mug/ml in acidic medium. Some common cations and anions are tolerable at low concentrations. The procedure is applicable for determination of total iron in potable water. Destruction of organic matter is required for contaminated surface waters or soil samples. 相似文献
68.
We developed an oblique-incidence reflectivity difference (OI-RD) scanning microscope for label-free imaging of microarrays of biomolecules upon solid substrates. We demonstrate that hybridization reactions in an oligonucleotide microarray fabricated upon a glass slide can be detected by such an OI-RD microscope. 相似文献
69.
Starting with Berry's hypothesis for fixed energy waves
in a classically chaotic system, and casting it in a Green
function form, we derive wavefunction correlations and density
matrices for few or many particles. Universal features of fixed
energy (microcanonical) random wavefunction correlation functions
appear which reflect the emergence of the canonical ensemble as
N↦∞. This arises through a little known asymptotic limit
of Bessel functions. The Berry random wave hypothesis in many
dimensions may be viewed as an alternative approach to quantum
statistical mechanics, when extended to include constraints and
potentials. 相似文献
70.
Burford N Edelstein E Landry JC Ferguson MJ McDonald R 《Chemical communications (Cambridge, England)》2005,(40):5074-5076
Subtle steric strain imposed by 2,6-dimethylphenyl substituents on N-Sb frameworks has enabled identification of the first acyclic dipnictadiazane and the first six-membered cyclotristibatriazane providing insight into the dehydrohalide coupling reaction of amines with halopnictines. 相似文献