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41.
A. Tillmann U. Kreiser P. Munzinger S. Frigge S. Buschbaum P. Schmid D. Loeffelmacher M. Merkwitz T. Theilig 《Journal of Electronic Materials》1998,27(12):1278-1285
The transient thermal behavior of 200 and 300 mm wafers in a new rapid thermal processing (RTP) chamber is investigated. The
AST3000 is a new RTP tool to meet the process requirements for both wafer sizes in 0.18 μm technologies and beyond. In this
paper, experimental results obtained on both 200 and 300 mm wafers for varying processing conditions are shown: spike anneal
experiments with fast ramp rates up to 200°C/s were performed. For standard anneal recipes, the steady state time is varied
in a broad range and also the inherent temperature uniformity is investigated. 相似文献
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Phycotoxins produced by various species of toxigenic microalgae occurring in the plankton are a global threat to the security
of seafood resources and the health of humans and coastal marine ecosystems. This has necessitated the development and application
of advanced methods in liquid chromatography coupled to mass spectrometry (LC-MS) for monitoring of these compounds, particularly
in plankton and shellfish. Most such chemical analyses are conducted in land-based laboratories on stored samples, and thus
much information on the near real-time biogeographical distribution and dynamics of phycotoxins in the plankton is unavailable.
To resolve this problem, we conducted ship-board analysis of a broad spectrum of phycotoxins collected directly from the water
column on an oceanographic cruise along the North Sea coast of Scotland, Norway, and Denmark. We equipped the ship with a
triple-quadrupole linear ion-trap hybrid LC-MS-MS system for detection and quantitative analysis of toxins, such as domoic
acid, gymnodimine, spirolides, dinophysistoxins, okadaic acid, pectenotoxins, yessotoxins, and azaspiracids (AZAs). We focused
particular attention on the detection of AZAs, a group of potent nitrogenous polyether toxins, because the culprit species
associated with the occurrence of these toxins in shellfish has been controversial. Marine toxins were analyzed directly from
size-fractionated plankton net tows (20 μm mesh size) and Niskin bottle samples from discrete depths, after rapid methanolic
extraction but without any further clean-up. Almost all expected phycotoxins were detected in North Sea plankton samples,
with domoic acid and 20-methylspirolide G being most abundant. Although AZA was the least abundant of these toxins, the high
sensitivity of the LC-MS-MS enabled detailed quantification, indicating that the highest amounts of AZA-1 were present in
the southern Skagerrak in the 3–20 μm size-fraction. The direct on-board toxin measurements enabled isolation of plankton
from stations with high AZA-1 levels and from the most suspicious size-fraction, i.e. most likely to contain the AZA-producer.
A large number (>100) of crude cultures were established by serial dilution and later screened for the presence of AZAs after
several weeks growth. From one crude culture containing AZA, a small dinoflagellate was subsequently isolated and brought
into pure culture. We have thus proved that even sophisticated mass spectrometers can be operated in ship laboratories without
any limitation caused by vibrations of the ship’s engine or by wave movement during heavy seas at wind forces up to nine Beaufort.
On-board LC–MS–MS is a valuable method for near real-time analysis of phycotoxins in plankton for studies on bloom dynamics
and the fate of toxins in the food web, and for characterization and isolation of putatively toxigenic organisms. 相似文献
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Stephan Tillmann 《Topology》2005,44(1):203-216
The A-polynomial of a manifold whose boundary consists of a single torus is generalised to an eigenvalue variety of a manifold whose boundary consists of a finite number of tori, and the set of strongly detected boundary curves is determined by Bergman's logarithmic limit set, which describes the exponential behaviour of the eigenvalue variety at infinity. This enables one to read off the detected boundary curves of a multi-cusped manifold in a similar way to the 1-cusped case, where the slopes are encoded in the Newton polygon of the A-polynomial. 相似文献
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Dr. Jayanta Ghosh Mirali Gheibi Dr. Tillmann Kalas Cristian Sarpe Bastian Zielinski Ramela Ciobotea Christoph Burghard Morscher Dr. Ingo Koehne Prof. Dr. Rudolf Pietschnig Dr. Arne Senftleben Prof. Dr. Thomas Baumert Dr. Hendrike Braun 《Chemphyschem》2023,24(12):e202300001
Temporally delayed, phase-locked coherent pairs of near IR femtosecond laser pulses were employed to study electronic coherences in molecular Nd3+-complexes at room temperature. Dissolved and solid complexes were studied under a confocal microscope set-up with fluorescence detection. The observed electronic coherence on a few hundred femtoseconds time scale is modulated by additional coherent wave packet dynamics, which we attribute mainly to be vibrational in nature. In future, the complexes may serve as prototypes for possible applications in quantum information technology. 相似文献