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排序方式: 共有269条查询结果,搜索用时 15 毫秒
261.
René van den Brink Yukihiko Funaki Gerard van der Laan 《European Journal of Operational Research》2013
The Reverse Talmud rule for bankruptcy problems applies the Constrained Equal Awards rule (CEA rule) for ‘large’ amounts of the estate, while it applies the Constrained Equal Losses rule (CEL rule) for ‘small’ amounts of the estate. The CEA rule, respectively CEL rule, can be axiomatized using the Exemption and Exclusion properties respectively. There is no rule that satisfies both these two properties. In this paper we axiomatize the Reverse Talmud rule by using compatible weaker versions of the Exemption and Exclusion properties. 相似文献
262.
Ternary semihypergroups are algebraic structures with one ternary associative hyperoperation. In this paper we give some properties of left (right) and lateral hyperideals in ternary semihypergroups. We introduce the notion of left simple, lateral simple, left (0-)simple and lateral 0-simple ternary semihypergroups and characterize the minimality and maximality of left (right) and lateral hyperideals in ternary semihypergroups. The relationship between them is investigated in ternary semihypergroups extending and generalizing the analogues results for ternary semigroups. 相似文献
263.
Masakiyo Tsunoda Ken-ichi Imakita Mamiko Naka Migaku Takahashi 《Journal of magnetism and magnetic materials》2006
The degree of order S of Mn–Ir layers and the exchange anisotropy of Mn–Ir/Co–Fe bilayers were investigated for various chemical compositions of Mn–Ir layers, underlayer materials, and underlayer thicknesses. It was found that: (1) The compositional range over which L12-phase Mn3Ir could be formed is 22–32 at% Ir and giant exchange anisotropy is obtained in this range. (2) Ru is favorable as an underlayer material for avoiding interdiffusion with the Mn–Ir layer during deposition on the temperature elevated substrate. (3) The underlayer thickness could be reduced to 5 nm while maintaining a giant exchange anisotropy in excess of 1 erg/cm2. 相似文献
264.
Mikiji Miyata Yasuhiro Kitahara Yukihiko Osaki Kiichi Takemoto 《Journal of inclusion phenomena and macrocyclic chemistry》1984,2(1-2):391-398
The inclusion polymerization of diene monomers with different sizes and shapes in apocholic acid canals was studied under -ray irradiation. It was found that the sizes and shapes of monomers profoundly influenced the microstructures of the corresponding polymers obtaied. Thus, polybutadiene contained a significant amount of 1,2-units like usual radical polymerization in solution. Polyisoprene consisted of a mixture of head-to-tail and head-to-head (tail-to-tail) addition. The introduction of two methyl groups into butadiene led to the synthesis of polymers with almost exclusively head-to-tail, 1,4-trans structure. 相似文献
265.
In this paper we consider a model of an economy with a common pool resource. Under decreasing returns to scale, it is well-known
that no Nash equilibrium attains Pareto efficiency. We examine whether it is possible to achieve Pareto efficiency and avoid
the tragedy of the commons through cooperation among players. For that purpose, we use the notion of a game in partition function
form. Whether or not the core exists depends crucially on the expectations of each coalition regarding the coalition formation
of the outsiders. If each coalition has pessimistic expectations, then the core always exists, while if it has optimistic
expectations, the core may be empty.
Received: January 1998/Final version: November 1998 相似文献
266.
Yasuyuki Irie Kensuke Naka 《Journal of polymer science. Part A, Polymer chemistry》2016,54(5):628-633
9H‐carbazole‐9‐ethyl and 9H‐carbazole‐9‐hexyl‐terminated polyhedral octasilicate (OS)‐core dendrimers, denoted as OS‐C2‐Cz and OS‐C6‐Cz, respectively, were prepared by ring‐opening reaction and subsequent condensation of octakis(propenyl succinicanhydrido)polyhedral octasilicate (OS‐SA) with 9H‐carbazole‐9‐ethanol (Cz‐C2‐OH) and 9H‐carbazole‐9‐hexanol (Cz‐C6‐OH), respectively. Both the dendrimers formed optical transparent coating films. In particular, the coating film of OS‐C2‐Cz was easily peeled off from a substrate and formed a free‐standing film. The results of X‐ray diffraction and differential scanning calorimeter suggest that the films of OS‐C2‐Cz and OS‐C6‐Cz were amorphous. Thermogravimetric analysis of OS‐C2‐Cz and OS‐C6‐Cz showed 10 wt % weight losses at 374 and 383 °C, respectively. Photoluminescence property revealed that the carbazole group in OS‐C2‐Cz is prevented the excimer formation, while the carbazole group in OS‐C6‐Cz formed the excimer. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 628–633 相似文献
267.
268.
Keiji Nagai Nobukatsu Nemoto Yukihiko Ueno Koji Ikeda Nobuo Takamiya Masao Kaneko 《Macromolecular Symposia》1992,59(1):257-266
Polysiloxanes containing pendant tris(2,2′-bipyridine)ruthenium(II) complex (Ru(bpy)32+) were prepared by reaction of polysiloxane-pendant 2,2′-bipyridine (PSiO-bpy) with cis-Ru(bpy)2Cl2. In methanol solution, the polymer pendant Ru(bpy)32+ showed absorption maximum at 456nm and emission maximum at around 609nm, both of which are shifted to longer wavelength than the monomeric Ru(bpy)32+. The lifetime τ0 of the excited polymer complex with low Ru(bpy)32+ content was almost the same as that of the monomeric one in methanol (830ns), but τ0 of the polymer with higher complex content was shorter because of a concentration quenching. In a solid state, τ0 was much shorter (306–503ns) than that in a methanol solution contrary to the conventional polymeric system. Higher complex content in the polymer film caused higher glass transition temperature (Tg), but shorter τ0. These results indicate concentration quenching in the polymer film. The excited polymer pendant Ru(bpy)32+ was quenched by oxygen, and the relative emission intensity followed the Stern-Volmer equation. In a methanol solution the quenching rate constant (kq) was the same order of magnitude as the monomeric complex, and independent of the complex content in the polymer. In a film, kq was higher for the polymer with higher complex content. 相似文献
269.
Kensuke Naka Rie Yamashita Tohru Nakamura Akira Ohki Shigeru Maeda Keigo Aoi Kaname Tsutsumiuchi Masahiko Okada 《Macromolecular rapid communications》1996,17(4):269-274
The peptide-containing block copolymer poly(N-acetyliminoethylene)-block-poly(L -phenylalanine) (1) formed large water-soluble aggregates in water due to the hydrophobic and hydrogen-bonding character of the poly(L -phenylalanine) block. The solution properties of 1 were compared with those of the block copolymer poly(N-acetyliminoethylene)-block-poly(N-benzoyliminoethylene) (2) with an analogous structure. 1 formed aggregates even though the poly(phenylalanine) segment was short as compared with 2 in which hydrophobic interaction may be the only driving force to form aggregates. The aggregates have strong capability of incorporating Lipase P and largely increase the hydrolysis activity against p-nitrophenyl propionate as compared with that of free Lipase P. 相似文献