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11.
Bartholomy O Credé V van Pee H Anisovich AV Anton G Bantes R Beloglazov Y Bogendörfer R Castelijns R Ehmanns A Ernst J Fabry I Flemming H Fösel A Freiesleben H Fuchs M Funke Ch Gothe R Gridnev A Gutz E Höffgen SK Horn I Hössl J Joosten R Junkersfeld J Kalinowsky H Klein F Klempt E Koch H Konrad M Kopf B Krusche B Langheinrich J Löhner H Lopatin I Lotz J Matthäy H Menze D Messchendorp J Morales C Novinski D Ostrick M Radkov A Reinnarth J Sarantsev AV Schadmand S Schmidt Ch Schmieden H Schoch B 《Physical review letters》2005,94(1):012003
Single pi(0) photoproduction has been studied with the CB-ELSA experiment at Bonn using tagged photon energies between 0.3 and 3.0 GeV. The experimental setup covers a very large solid angle of approximately 98% of 4pi. Differential cross sections dsigma/dOmega have been measured. Complicated structures in the angular distributions indicate a variety of different resonances being produced in the s channel intermediate state gammap-->N(*)(Delta(*))-->ppi(0). A combined analysis including the data presented in this letter along with other data sets reveals contributions from known resonances and evidence for a new resonance N(2070)D15. 相似文献
12.
Several methods are presented for the routine ultra-trace analytical monitoring of inorganic and organic anions and cations on the surface and in the native oxide of silicon wafers--the wafer-surface water-extraction method, the vapor-phase-decomposition method, and the re-dissolving method. Electrokinetic injection, sample stacking, and electrolyte composition were, therefore, optimized and made robust. For electrokinetic injection with transient isotachophoretic preconcentration a linear range of 0.05 to 0.5 micromol L(-1) was obtained; for sample stacking the linear range was 0.5 to 10 micromol L(-1), even in the presence of up to 750 micromol L(-1) hydrofluoric acid. Inorganic anions and monovalent carboxylic acids are predominately dissolved in the aqueous layer on the wafer surface whereas dicarboxylic acids are chemically bonded to the silanol groups and form esters. 相似文献
13.
D J Van Tasell D A Fabry L M Thibodeau 《The Journal of the Acoustical Society of America》1987,81(5):1586-1597
Confusion matrices for seven synthetic steady-state vowels were obtained from ten normal and three hearing-impaired subjects. The vowels were identified at greater than 96% accuracy by the normals, and less accurately by the impaired subjects. Shortened versions of selected vowels then were used as maskers, and vowel masking patterns (VMPs) consisting of forward-masked threshold for sinusoidal probes at all vowel masker harmonics were obtained from the impaired subjects and from one normal subject. Vowel-masked probe thresholds were transformed using growth-of-masking functions obtained with flat-spectrum noise. VMPs of the impaired subjects, relative to those of the normal, were characterized by smaller dynamic range, poorer peak resolution, and poorer preservation of the vowel formant structure. These VMP characteristics, however, did not necessarily coincide with inaccurate vowel recognition. Vowel identification appeared to be related primarily to VMP peak frequencies rather than to the levels at the peaks or to between-peak characteristics of the patterns. 相似文献
14.
15.
R. Hoelzl K.-J. Range L. Fabry 《Applied Physics A: Materials Science & Processing》2002,75(4):525-534
Based on experimental findings we set up calculations of numerical modeling of gettering efficiencies for Cu in various silicon
wafers. Gettering efficiencies for Cu were measured by applying a reproducible spin-on contamination in the 1012 atoms/cm2 range, followed by a thermal treatment to redistribute the metallic impurity. Subsequently, the wafers were analyzed by a
novel wet chemical layer-by-layer etching technique in combination with inductively coupled plasma mass spectrometry. We investigated
p/p+ and n/n+ epitaxial wafers with different doping levels and different substrate-doping species. We have also investigated
gettering efficiencies of phosphorus-diffused p- and n-type wafers. Heavilyboron doped silicon exhibited a gettering efficiency
of ∼100%, while gettering by n+ silicon occurred for doping levels >3×1019 atoms/cm3 only. In another set of experiments we investigated the dependence of the gettering efficiency of p-type wafers with poly-silicon
back sides for different cooling rates and Cu spiking levels. A strong dependence on both parameters was found. Cu gettering
in p/p+ epitaxial wafers was modeled by calculating the increased solubility of Cu in p+ silicon compared to non-doped silicon
taking into account the Fermi-level effect, which stabilizes donors in p+ silicon, and the pairing reaction between Cu and
B. Calculated gettering efficiencies were in very good agreement with experimental results. Gettering in n+ silicon was similarly
modeled in terms of pairing reactions and the Fermi-level effect. But, for n-type silicon, many experimental uncertainties
existed; thus, we applied our expressions to solubility data of Hall and Racette to obtain the unknown parameters. The empirical
calculations were in good agreement even with results on n/n+ wafers. For phosphorus-diffused wafers we had to consider an
excess vacancy concentration of 1.2–5.5 times the equilibrium concentration to explain the experimental findings by the model.
Gettering by poly-silicon back sides was simulated by solving the time-dependent diffusion equation with boundary conditions
that take into account different surface reaction rates of silicon point defects. Using this advanced model, the experimentally
measured gettering efficiencies were reproduced within the uncertainty of the measurement.
Received: 3 September 2001 / Accepted: 4 September 2001 / Published online: 20 December 2001 相似文献
16.
E. P. Fabry 《Experiments in fluids》1998,24(1):39-46
A new 3D PIV system combining holography and stereoscopic PIV is presented. The double pulsed holographic recording relies
on the forward scattering of particles in the laser sheet. The holographic images of the particles are used for a stereoscopic
PIV analysis. An imaging system with a rightangle prism is used to acquire a stereoscopic pair of images. The application
of the system to the vortex flow from an inclined delta wing shows the prospects and limitations of the technique.
Received: 23 December 1996/Accepted: 1 June 1997 相似文献
17.
L. Fabry 《Analytical and bioanalytical chemistry》1997,357(2):148-150
Analytics is a professional and systematic compilation of instances for the inference of problem solving truths. Relevant
analytical results are the starting point of inductive learning in engineering. In the semiconductor industry, diagnostic
investigations must be based on both process and product monitoring using trace-analytical methods. The analyst’s strive for
detection power and an increasing number of analytes are the key and flywheel of engineering knowledge.
Received: 9 October 1995 / Accepted: 14 May 1996 相似文献
18.
19.
Fabry B Maksym GN Hubmayr RD Butler JP Fredberg JJ 《Journal of magnetism and magnetic materials》1999,194(1):120-125
Magnetic twisting cytometry (MTC) measures cellular mechanical properties, such as cell stiffness and viscosity, by applying mechanical stress to specific cell surface receptors via ligand-coated ferromagnetic beads. MTC measures simultaneously the rotation of approximately 50,000 beads attached to 20,000 - 40,000 cells. Here we show direct evidence of heterogeneous bead behavior and examine its consequences in the interpretation of cell mechanical properties. 相似文献
20.
G. Pepponi B. Beckhoff T. Ehmann G. Ulm C. Streli L. Fabry S. Pahlke P. Wobrauschek 《Spectrochimica Acta Part B: Atomic Spectroscopy》2003,58(12):2245-2253
Organic contamination is starting to play an important role in the production and quality control of Si wafers. For the traceability of the source of contamination, information on the chemical binding conditions is very valuable. A near edge X-ray absorption fine structure (NEXAFS) investigation is the natural development of total reflection X-ray fluorescence (TXRF) analysis of the wafer surfaces able to solve the problem of speciation. The plane grating monochromator beamline for undulator radiation of the Physikalisch-Technische Bundesanstalt at the electron storage ring BESSY II, which provides photon energies between 30 eV and 1.9 keV for the specimen excitation, is an ideal excitation source for TXRF-NEXAFS experiments that require a high resolving power and a sufficient photon flux for trace analysis of low Z elements. The contaminants have been diluted and deposited as droplets on wafer pieces thoroughly cleaned after the cutting. The K edges of C, N, O have been examined. Some discrepancies have been found in the analysis of the same compounds in two different beamtimes; molecular orientation is pointed to as the cause for the difference in magnitude of the resonances. The unintentional contamination has been identified as mainly composed of aliphatic chains. 相似文献