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81.
D. Okai R. Nagai G. Motoyama T. Fukami T. Yamasaki Y. Yokoyama H.M. Kimura A. Inoue 《Physica C: Superconductivity and its Applications》2010,470(20):1048-1051
The superconducting property of Zr(1−x)Cox (x = 10–50 at.%) alloys and a Zr55Co30Al15 bulk metallic glass fabricated using techniques of rapid solidification was investigated. The Zr55Co30Al15 alloy crystallized by heat treatment in a vacuum atmosphere exhibited superconductivity of Tc,on = 2.4 K. This was attributable to the superconducting property of a crystalline Zr–Co alloy precipitated in the Zr55Co30Al15 alloy. The Tc,on of the crystalline Zr(1−x)Cox alloy was sensitive to the Co content. The increase of Co content for the Zr(1−x)Cox alloy led to the decrease of Tc,on. The Zr(1−x)Cox alloy exhibited superconductivity of a maximum Tc,on = 3.9 K for the Zr80Co20 alloy with superconducting nanocrystal particles embedded in the amorphous matrix. 相似文献
82.
Usui K Hiratsuka A Shiseki K Maruo Y Matsushima T Takahashi K Unuma Y Sakairi K Namatame I Ogawa Y Yokoyama K 《Electrophoresis》2006,27(18):3635-3642
We developed a polymeric 2-DE chip system. The chip consisted of an IEF region, an SDS-PAGE region, a valveless connection port, and a sample introduction port. A "junction structure" as a valveless connection port, which allowed separating and connecting the first- and second-dimensional gels, was fabricated between their regions. A "solution inlet" as a sample introduction port was fabricated to perform the liquid and sample introductions without solution leakage. Simultaneous sample monitoring was performed using the on-chip detection system. The performances of the system were demonstrated using commercially available proteins as a standard specimen and tissue-extracted proteins as the real samples. All procedures were employed without any movement of relocation part. This new 2-D separation system realized improved labor-intensive operations and a reduced experimental time. 相似文献
83.
Tomohiro Masukawa Akihiro Yokoyama Tsutomu Yokozawa 《Macromolecular rapid communications》2009,30(16):1413-1418
Well‐defined diblock copolymers composed of poly(N‐octylbenzamide) and polystyrene were synthesized by reversible addition‐fragmentation chain transfer (RAFT) polymerization of styrene with a polyamide chain transfer agent (CTA) prepared via chain‐growth condensation polymerization. Synthesis of a dithioester‐type macro‐CTA possessing the polyamide segment as an activating group was unsatisfactory due to side reactions and incomplete introduction of the benzyl dithiocarbonyl unit. On the other hand, a dithiobenzoate‐CTA containing poly(N‐octylbenzamide) as a radical leaving group was easily synthesized, and the RAFT polymerization of styrene with this CTA afforded poly(N‐octylbenzamide)‐block‐polystyrene with controlled molecular weight and narrow polydispersity.
84.
K. Sakamoto K. Itoh T. Takashima S. Yokoyama K. Yamazaki 《Journal of Radioanalytical and Nuclear Chemistry》1980,60(2):323-342
Uranium concentrations in three types of inclusions of the Allende (C III), a bulk sample of the Plainview (H5), and a bulk
and 5 to 15 density separates of the Huckitta pallasite were determined and discussed by comparing the results from homogenized
fission track and/or239Np analyses with the133Xe results. Stepwise heating experiment revealed that the133Xe release from the Plainview is bimordal and incomplete by a simple heating at 1600 °C, and that the133Xe releases in the Huckitta bulk and metallic samples are multitudinous but can be extracted rather completely at 1600–1700
°C. In the Huckitta, uranium-rich phase (∼100 ppb) was in the lightest density fraction of d=2.9–3.3, but the bulk uranium
was found to be mostly from the heavy metal-rich fraction of d>4.2. 相似文献
85.
Tanaka S Kubo Y Yokoyama Y Toda A Taguchi K Kajioka H 《The Journal of chemical physics》2011,135(23):234503
We investigated the phase separation phenomena in dilute surfactant pentaethylene glycol monodedecyl ether (C(12)E(5)) solutions focusing on the growth law of separated domains. The solutions confined between two glass plates were found to exhibit the phase inversion, characteristic of the viscoelastic phase separation; the majority phase (water-rich phase) nucleated as droplets and the minority phase (micelle-rich phase) formed a network temporarily, then they collapsed into an usual sea-island pattern where minority phase formed islands. We found from the real-space microscopic imaging that the dynamic scaling hypothesis did not hold throughout the coarsening process. The power law growth of the domains with the exponent close to 1/3 was observed even though the coarsening was induced mainly by hydrodynamic flow, which was explained by Darcy's law of laminar flow. 相似文献
86.
Hidekatsu Yokoyama Toshiyuki Sato Tateaki Ogata Hiroaki Ohya-Nishiguchi Hitoshi Kamada 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1997,129(2):201-206
A signal detector of longitudinally detected ESR (LODESR) is independent of the resonant frequency. We developed anin vivoLODESR spectrometer operating in the regions of 300, 700, and 900 MHz. Using this apparatus, we estimated signal intensities at different operating frequencies obtained from non- or high-dielectric loss phantoms that contained nitroxide radical solutions and from live rats that had received a nitroxide radical. Our result, higher signal intensities in the high-dielectric loss samples (such as physiological saline solution and animals) at a lower frequency, shows that the influence of a decrease in dielectric loss dominates over the signal reduction caused by smaller Zeeman splitting. We believe that this finding strongly supports anin vivoESR resonant frequency that tends to be low. 相似文献
87.
Signal intensities of longitudinally detected ESR (LODESR) of 1,1-diphenyl-2-picrylhydrazyl powder were precisely measured
at 250 to 950 MHz under a constant magnetic field microwave that was applied using a single-turn coil. The LODESR signal intensity
was reduced linearly due to smaller Zeeman splitting. Because the noise level was constant, the sensitivity of LODESR was
approximately proportional to the resonant frequency. As far as we know, this study represents the first attempt to measure
precisely the relationship between the signal intensities and resonant frequencies of ESR in an experimental condition. 相似文献
88.
89.
Hidekatsu Yokoyama 《Applied magnetic resonance》2009,36(1):49-59
Coarse control and fine control of the resonant frequency of a loop-gap resonator (LGR) operating at an electron paramagnetic
resonance (EPR) frequency of ca. 650 MHz were achieved using a single-turn coil with a varactor diode attached (a frequency
shift coil). When the distance between the LGR and the frequency shift coil was changed from 15 to 10 mm under the condition
of constant voltage to the varactor diode (0 V), a shift of the resonant frequency of the LGR of ca. 20 MHz was observed (coarse
frequency control). When the voltage applied to the varactor diode was changed from 0 to 15 V at the same distance between
the LGR and the frequency shift coil (10 mm), a shift of the resonant frequency of the LGR of ca. 200 kHz was observed (fine
frequency control). There were no significant changes in sensitivity of EPR measurements of a phantom (comprised of agar with
a nitroxide radical and physiological saline solution) without and with the frequency shift coil. The EPR sensitivity did
not change discernibly when the resonant frequency was shifted by the frequency shift coil. Furthermore, radio-frequency phase
adjustment for homodyne detection could be performed by using the frequency shift coil without applying frequency modulation
to the carrier wave. 相似文献
90.
PVTx relationships and solid-liquid equilibria for the m-xylene-p-xylene system under high pressures
PVTx relationships of the m-xylene-p-xylene system have been measured with a glass piezometer at 283.15 and 298.15 K and pressures up to 200 MPa, or up to the point of solidification of m-xylene where this occurred at a lower pressure. Freezing pressures of m-xylene were observed as a discontinuity in the volume at increasing pressure. Approximate solid-liquid equilibria under high pressures were obtained from the freezing pressure measurement. The Carnahan-Starling-van der Waals (CS-vdW) equation of state was used to correlate the PVTx data. The solid-liquid equilibria under high pressures were calculated with the CS-vdW equation of state for the liquid phase and a simple equation of state for the solid phase. In order to test the validity of the calculation method, the solid-liquid equilibrium relationships of the benzene-cyclohexane system were also calculated. It was found that the solid molar volume should be treated as a function of temperature and/or pressure to fit the experimental data. 相似文献