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111.
Let \({\varphi: \mathbb{P}^N_K\to\mathbb{P}^N_K}\) be a morphism of degree d ≥ 2 defined over a field K that is algebraically closed field and complete with respect to a nonarchimedean absolute value. We prove that a modified Green function \({\hat{g}_\varphi}\) associated to \({\varphi}\) is Hölder continuous on \({\mathbb{P}^N(K)}\) and that the Fatou set \({\mathcal{F}(\varphi)}\) of \({\varphi}\) is equal to the set of points at which \({\hat{g}_\Phi}\) is locally constant. Further, \({\hat{g}_\varphi}\) vanishes precisely on the set of points P such that \({\varphi}\) has good reduction at every point in the forward orbit \({\mathcal{O}_\varphi(P)}\) of P. We also prove that the iterates of \({\varphi}\) are locally uniformly Lipschitz on \({\mathcal{F}(\varphi)}\) . 相似文献
112.
Kawaguchi M Ito R Sakui N Okanouchi N Saito K Nakazawa H 《Journal of chromatography. A》2006,1105(1-2):140-147
A novel method for the trace analysis of 17beta-estradiol (E2) in river water sample was developed, which involved stir bar sorptive extraction (SBSE) with in situ acylation (first derivatization) and thermal desorption (TD) with quartz wool assisted (QWA) in tube silylation (second derivatization), followed by gas chromatography-mass spectrometry (GC-MS), and is called the "dual derivatization method." The optimum conditions for SBSE with in situ acylation, such as the volume of acetic acid anhydride and the extraction time, were investigated. In addition, the optimum conditions for TD with QWA in tube silylation, such as the volume of N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) and the TD temperature and hold time, were investigated as well. The detection limit (S/N = 3) and the quantitation limit (S/N>10) of E2 in the river water sample were 0.5 and 2 pg ml(-1) (ppt), respectively, by the dual derivatization method. In addition, the detection limit was 0.1 pg ml(-1) by using dual derivatization method with multi-shot mode. The calibration curve for E2 was linear in the range of 0.002-10 ng ml(-1) with correlation coefficients >0.999. The average recoveries of E2 (n = 6) at the concentrations of 0.05 and 1.0 ng ml(-1) from the river water sample were 93.1 (RSD: 1.4%) and 98.4% (RSD: 0.8%), respectively, with correction using the added surrogate standard, 17beta-estradiol-(13)C(4). This simple, accurate, sensitive and selective analytical method may be applicable to the determination of trace amounts of E2 in water samples. 相似文献
113.
Takahiro Tsukahara Yusuke Sakamoto Daisuke Aoshima Makoto Yamamoto Yasuo Kawaguchi 《Experiments in fluids》2012,52(4):877-890
The installation of windbreak sand fences around sand dunes is one of the most promising methods to suppress windblown sand
movement. In the study reported in this paper, we investigated the influence and validity of a small fence mounted on a model
sand dune, in order to understand the fence’s suppression mechanism on the sand movement. The flow field around the dune and
the process of sand-dune erosion were measured using LDV, PIV, and laser-sheet visualization techniques. A non-porous fence
was found to suppress sand movements in its upstream area, but to enhance erosion downstream of the fence. This intensive
erosion was caused by separated shear flow from the leading edge of the fence. In this study, four levels of porosity rate
of the fence were tested. The fence-porosity dependences of the turbulent flow field and the erosion were discussed. The shapes
of eroded sand dunes were found to depend on the porosity rate. The relationship between the sand-dune erosion and the flow
field around the dune was illustrated with schematic diagrams. We concluded that the most desirable fence porosity should
be 30% in order to avoid dune erosion if installed at a middle height on the stoss surface of a dune. This porosity provides
a mean velocity reduction with avoiding a separated flow, although the flow bleeding through the porous fence is accompanied
by grid turbulence and induces serious erosion in a narrow space behind the fence. Furthermore, we confirmed that the empirical
correlation of the critical friction velocity can be applied to sand movements influenced by a fence. 相似文献
114.
Hiroyuki Tanaka Toshifumi Shiroya Minako Hanasaki Tatsushi Isojima Hisao Takeuchi Haruma Kawaguchi 《Macromolecular Symposia》2008,266(1):81-84
Summary: Protein chips are important tools for high-throughput analysis of biological events. We have developed a novel method to prepare a protein-based hydrogel, that is, a “Three-Dimensional Nano-structured Protein Hydrogel” (3-D NPH), which is composed of protein and polymer nano-particles. The 3-D NPH could be easily prepared by dispensing a protein and polymer mixture on a substrate. Surprisingly, gold particles conjugated with protein A diffused into the 3-D NPH which was made of mouse IgG through the pores. We have shown that the protein chips made with our 3-D NPH method has tremendously improved sensitivity in detecting protein-protein interactions compared with that of direct protein immobilization methods. 相似文献
115.
Kamagata K Kawaguchi T Iwahashi Y Baba A Fujimoto K Komatsuzaki T Sambongi Y Goto Y Takahashi S 《Journal of the American Chemical Society》2012,134(28):11525-11532
A method was developed to detect fluorescence intensity signals from single molecules diffusing freely in a capillary cell. A unique optical system based on a spherical mirror was designed to enable quantitative detection of the fluorescence intensity. Furthermore, "flow-and-stop" control of the sample can extend the observation time of single molecules to several seconds, which is more than 1000 times longer than the observation time available using a typical confocal method. We used this method to scrutinize the fluorescence time series of the labeled cytochrome c in the unfolded state. Time series analyses of the trajectories based on local equilibrium state analysis revealed dynamically differing substates on a millisecond time scale. This system presents a new avenue for experimental characterization of the protein-folding energy landscape. 相似文献
116.
Atsushi?NarumiEmail author Yudai?Kimura Seigou?Kawaguchi 《Colloid and polymer science》2012,290(4):379-384
The precipitation polymerizations of N-tert-butylacrylamide (NtBAM) in water are demonstrated; for example, the polymerization with potassium peroxodisulfate using a 15 g L−1 (118 mmol L−1) concentration of NtBAM in the feed ([NtBAM]0) was performed at 70 °C for 12 h, quantitatively producing poly(N-tert-butylacrylamide) particles with a number-average diameter (d
n) of 203 nm and a coefficient of variation (C
v) of 4.7%. The particle sizes were controlled in the d
ns range between 75 and 494 nm by changing the monomer feeds or adding an electrolyte such as NaCl. The solid contents in the
resulting aqueous latex solutions ranged from 0.1 to 1.5%, whereas it increased to 4.8% by applying a “shot-growth” technique.
The polymerization in water under a somewhat unique condition is described, which was started from a heterogeneous system
due to the presence of significantly large amounts of monomers ([NtBAM]0 = 50 g L−1). This also provided monodisperse latexes with the d
n of 370 nm in 96% yield, in which the solid content reached 4.9%. 相似文献
117.
Shigekazu Okumura Nami Yasuoka Kenichi Kawaguchi Yu Tanaka Mitsuru Ekawa 《Journal of Crystal Growth》2012,340(1):87-91
An investigation was performed of columnar InAs quantum dots (CQDs) with modulated tensile-strained InGaAsP barriers in which the amount of tensile strain in the upper parts was higher than in the lower parts, the dots being deposited on an InP substrate grown by metalorganic vapor phase epitaxy. The smaller tensile strain of the barrier layers in the lower parts made the photoluminescence (PL) wavelength longer while the larger tensile strain of the barrier layers in the upper parts increased the strain compensation of the CQDs. Compared to CQDs with uniformly tensile-strained barriers, 1.55 μm emission was obtained at a higher average strain of barrier layers. By utilizing modulated tensile-strained barriers, triple-stacking of 12-fold CQDs with a PL wavelength of 1.55 μm using 30-nm-thick spacer layers was achieved with good crystallinity, indicating suitability for fabrication of high density CQDs. 相似文献
118.
Koide Y Kawaguchi M Urano Y Hanaoka K Komatsu T Abo M Terai T Nagano T 《Chemical communications (Cambridge, England)》2012,48(25):3091-3093
We have designed and synthesized a reversible near-infrared (NIR) fluorescence probe, 2-Me TeR, for reactive oxygen species (ROS), utilizing the redox properties of the tellurium (Te) atom. 2-Me TeR is oxidized to fluorescent 2-Me TeOR by various ROS, while the generated 2-Me TeOR is quickly reduced in the presence of glutathione to regenerate 2-Me TeR. This redox-induced reversible NIR-fluorescence response of 2-Me TeR allowed us to detect the endogenous production of ROS and subsequent homeostatic recovery of the intracellular reductive environment in hydrogen peroxide-stimulated HL-60 cells. This probe is expected to be useful for monitoring the dynamics of ROS production continuously in vivo. 相似文献
119.
Gen Tanaka Ikuhiko Nakase Yasunori Fukuda Ryo Masuda Shinya Oishi Kazuya Shimura Yoshimasa Kawaguchi Tomoka Takatani-Nakase Ülo Langel Astrid Gräslund Katsuya Okawa Masao Matsuoka Nobutaka Fujii Yasumaru Hatanaka Shiroh Futaki 《Chemistry & biology》2012,19(11):1437-1446
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120.
In this paper, three-dimensional Brownian dynamics simulation has been conducted for dilute micellar surfactant solution under
a steady shear flow. The rodlike micelle in surfactant solution is assumed as a rigid rod made up of lined-up beads. The Lennard–Jones
potential and soft-sphere potential are employed and taken as the inter-bead potentials for end–end beads and interior–interior
beads, respectively. The motion of the rodlike micelles is determined by solving the translational and rotational equations
for each rod under hydrodynamic drag force, Brownian force and inter-rod potential force. Velocity Verlet algorithm has also
been exerted in the simulation. The micellar network structure is formed at low shear rates and destroyed by high shear rates.
The computed shear viscosities and the first normal stress coefficient represent shear thinning characteristics. The paper
reveals the relation between rheology and microstructure of surfactant solution at different shear rates. The effect of surfactant
solution concentration rested on the micellar structures and rheological properties has also been investigated. 相似文献