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81.
Jun-ichi Maskawa 《Physica A》2007,383(1):90-95
We examine the correlation of the limit price with the order book, when a limit order comes. We analyzed the Rebuild Order Book of Stock Exchange Electronic Trading Service, which is the centralized order book market of London Stock Exchange. As a result, the limit price is broadly distributed around the best price according to a power-law, and it is not randomly drawn from the distribution, but has a strong correlation with the size of cumulative unexecuted limit orders on the price. It was also found that the limit price, on the coarse-grained price scale, tends to gather around the price which has a large size of cumulative unexecuted limit orders. 相似文献
82.
Several human lung samples were dissected into lobes and uranium and silicon contents in each lobe were determined by the fission track method and the inductively coupled plasma-atomic emission spectrometry (ICP-AES), respectively. It was found that both uranium and silicon concentrations were high in the upper lobe compared with those in the lower one. Though the tendency may be mainly interpreted by the deposition way of airborne dust in the lung, the higher U/Si concentration ratio in the upper part than that in the lower part of lungs may suggest the partial removal of uranium deposited in the lower part of the tissue. 相似文献
83.
Katsumi Katoh Shunsuke Ito Yuji Ogata Jun-ichi Kasamatsu Hiroshi Miya Masaaki Yamamoto Yuji Wada 《Journal of Thermal Analysis and Calorimetry》2010,99(1):159-164
In order to prevent the spontaneous ignition of nitrocellulose (NC), NC is stabilized by washing with industrial water in
its synthesis process. However, there is a possibility that the components in industrial water contribute to the thermal stability
of NC. In this way, the purpose of this study is to clarify the effect of industrial water components on the thermal stability
of NC. In experiments, a heat flux calorimeter was used to observe the thermal behavior of NC with the residue of vaporized
industrial water. The induction period of heat release of NC with 2-mass% residues was approximately 2–5 h shorter than that
of NC alone whose induction period was observed at 7 h. Those results indicate that the residue destabilized NC. On the other
hand, when the additive amount of the residue was increased, the induction period gradually increased as well. Based upon
these results, we assume that inorganic salts contributing to stabilization and destabilization competitively coexist in the
industrial water components. The same thermal analysis was performed on NC with CaCO3, CaSO4, CaCl, ZnSO4, NaCl, and CuCl. Those salts are predicted to exist in the industrial water. In the results, the induction period of NC with
2-mass% CaCO3 was approximately 15-h longer than that of NC alone, while the induction period with the inorganic salts CaSO4, CaCl, ZnSO4, NaCl, and CuCl was 4–5-h shorter. Therefore, when the industrial water components accumulate in NC, the destabilization
by inorganic salts such as CaSO4, CaCl, ZnSO4, NaCl, and CuCl and the stabilization by compounds such as CaCO3 are thought to countervail against each other. 相似文献
84.
We find numerically that a regular array of isolated ring defects can exist as a stable state in a highly chiral liquid crystal confined in a thin cell imposing fixed planar anchoring at the parallel confining surfaces. This peculiar defect structure can be stable when the cell thickness d is around 3/4 of the helical pitch p. A cell of thickness 3p/4 with parallel surface anchoring is incompatible with helical alignment that favors d=mp/2 (with m being an integer). Formation of ring defects can thus be regarded as a result of frustrations between the helical alignment with a specific pitch and the confining surfaces that prevent it. 相似文献
85.
Jun-ichi Mukuno 《Geometriae Dedicata》2014,168(1):359-368
If a homogeneous space $G/H$ is acted properly discontinuously upon by a subgroup $\varGamma $ of $G$ via the left action, the quotient space $\varGamma \backslash G/H$ is called a Clifford–Klein form. In Calabi and Markus (Ann Math (2) 75: 63–76, 1962) proved that there is no infinite subgroup of the Lorentz group $O(n+1,\,1)$ whose left action on the de Sitter space $O(n+1,\,1)/O(n,\,1)$ is properly discontinuous. It follows that a compact Clifford–Klein form of the de Sitter space never exists. In the present paper, we provide a new extension of the theorem of E. Calabi and L. Markus to a certain class of Lorentzian manifolds that are not necessarily homogeneous by using the techniques of differential geometry. 相似文献
86.
Sachiko Kaidzu Kazunobu Sugihara Masahiro Sasaki Aiko Nishiaki Hiroyuki Ohashi Tatsushi Igarashi Masaki Tanito 《Photochemistry and photobiology》2023,99(4):1142-1148
Basal cells in the corneal limbus play an important role in the turnover cycle because they are the source of all cells that constitute the corneal epithelium. We examined the penetration depth of ultraviolet (UV) light in the corneal limbus and assessed the safety of Far-UV-C on stem cells in the basal area of the corneal limbus. Rats were irradiated with UV at peaks of 207, 222, 235, 254 and 311 nm while under anesthesia. The UV penetration depth in the rat corneal limbal epithelium was wavelength dependent: 311 nm UV-B and 254 nm UV-C reached the basal cells of the epithelium, and 235 nm radiation reached the middle area; however, 207 and 222 nm UV-C reached only the superficial layer of the epithelium. Porcine cornea, which is similar to the human eye in size and structure, were irradiated with 222 and 254 nm UV-C. As in rats, 222 nm UV-C reached only the superficial layer of the porcine corneal limbal epithelium. These results indicate that Far-UV-C, such as radiation of wavelengths of 207 and 222 nm, could not reach corneal epithelial stem cells, i.e. the cells remained intact. It is unlikely that the turnover of the corneal epithelium is obstructed or disrupted by exposure to Far-UV-C. 相似文献
87.
The reaction of an N-acyliminium ion with an alkyl iodide and hexabutyldistannane took place to give the alkylation product. A mechanism involving the addition of an alkyl radical to an N-acyliminium ion to produce the corresponding radical cation has been suggested. 相似文献
88.
Two novel aromatic glycosides were obtained from Puerariae Radix and their chemical structures were characterized. 相似文献
89.
Takako Toda Hiroshi Igarashi Masahiro Watanabe 《Journal of Electroanalytical Chemistry》1999,460(1-2)
The design of high performance cathode electrocatalysts is essential for polymer–electrolyte fuel cells, which are now attracting enormous interest as a primary power source for zero-emission electric vehicles. We have discovered a significant enhancement of electrocatalytic activity of Pt by alloying with Fe, and found a maximum activity at ca. 50% Fe content, which results in 25 times higher activity than pure Pt activity. It was confirmed experimentally at Pt–Fe bulk alloys that the alloy catalyst surface consists of a pure Pt skin-layer (<1 nm in thickness) that is modified in the electronic structure by that of the bulk alloy. The enhancement could be well explained by the 5d-vacancy of the surface, but not by Pt interatomic distance or roughening of the surfaces. 相似文献
90.
Jun-ichi Matsuo Ryosuke Okuno Kosuke Takeuchi Mizuki Kawano Hiroyuki Ishibashi 《Tetrahedron letters》2010,51(29):3736-3737
Optimized reaction conditions for the preparation of various 2-monosubstituted 3-ethoxycyclobutanones are described. 2-Monoalkyl 3-ethoxycyclobutanones were efficiently prepared by the reaction of the corresponding carboxylic acid chlorides and an excess amount of ethyl vinyl ether in the presence of diisopropylethylamine at 90 °C in a sealed tube. 2-Monoaryl 3-ethoxycyclobutanones were prepared by using 2,6-lutidine as a base in the above-mentioned procedure. 相似文献