全文获取类型
收费全文 | 881篇 |
免费 | 42篇 |
国内免费 | 5篇 |
专业分类
化学 | 727篇 |
晶体学 | 11篇 |
力学 | 8篇 |
数学 | 14篇 |
物理学 | 168篇 |
出版年
2021年 | 6篇 |
2020年 | 12篇 |
2019年 | 11篇 |
2017年 | 8篇 |
2016年 | 15篇 |
2015年 | 25篇 |
2014年 | 26篇 |
2013年 | 38篇 |
2012年 | 38篇 |
2011年 | 46篇 |
2010年 | 24篇 |
2009年 | 22篇 |
2008年 | 47篇 |
2007年 | 40篇 |
2006年 | 40篇 |
2005年 | 38篇 |
2004年 | 33篇 |
2003年 | 22篇 |
2002年 | 29篇 |
2001年 | 30篇 |
2000年 | 25篇 |
1999年 | 14篇 |
1998年 | 13篇 |
1997年 | 16篇 |
1996年 | 16篇 |
1995年 | 10篇 |
1994年 | 10篇 |
1993年 | 7篇 |
1992年 | 17篇 |
1991年 | 9篇 |
1990年 | 8篇 |
1989年 | 7篇 |
1988年 | 8篇 |
1986年 | 8篇 |
1985年 | 17篇 |
1984年 | 7篇 |
1982年 | 11篇 |
1981年 | 9篇 |
1980年 | 10篇 |
1979年 | 8篇 |
1978年 | 10篇 |
1977年 | 9篇 |
1976年 | 15篇 |
1975年 | 8篇 |
1974年 | 13篇 |
1973年 | 16篇 |
1971年 | 11篇 |
1969年 | 8篇 |
1968年 | 8篇 |
1967年 | 9篇 |
排序方式: 共有928条查询结果,搜索用时 31 毫秒
1.
Curved Ferroelectric Liquid Crystal Matrix Displays Driven by Field-Sequential-Color and Active-Matrix Techniques 总被引:1,自引:0,他引:1
Hideo Fujikake Hiroto Sato Takeshi Murashige Yoshihide Fujisaki Taiichiro Kurita Tadahiro Furukawa Fumio Sato 《Optical Review》2006,13(1):14-19
This paper describes a curved field-sequential-color matrix display using fast-response ferroelectric liquid crystal. Black
matrix and transparent electrode patterns were formed on a thin plastic substrate by a transfer method from a glass substrate.
While a composite film of liquid crystal and micro-polymers of walls and fibers was formed between the flexible substrates
by printing, laminating and curing processes of a solution of monomers and liquid crystal, the mechanical stability was enhanced
by use of multi-functional monomers to form large display panels. The image pixels of the matrix panel were driven by an active
matrix scheme using an external switch transistor array at a frequency of 180 Hz for intermittent three-primary-color backlight
illumination. The flexible A4-paper-sized color display with 24 × 16 pixels and 60 Hz field frequency was demonstrated by
illuminating it with sequential three-primary-color lights from light-emitting diodes of the backlight. Our display system
is useful in various information displays because of its freedom of setting and location. 相似文献
2.
H. Sunaoshi Y. Fukashiro M. Furukawa M. Yamauchi S. Hayashibe T. Shinozuka M. Fujioka I. Satoh M. Wada S. Matsuki 《Hyperfine Interactions》1993,78(1-4):241-245
The ground state hyperfine splitting of87Sr+ was measured with a precision of 1×10–8. The experiments were performed with an RF ion trap connected to an ISOL (isotope separator on-line), where all the possible transitions between Zeeman sublevels were observed by a laser-microwave double resonance method. The magnetic dipole hyperfine constant was determined to beA=–1 000 473.673 (11) kHz. 相似文献
3.
Akihiko Yukie 《Mathematische Annalen》1992,292(1):355-374
Partially supported by NSF Grant DMS-8803085, DMS-8610730 相似文献
4.
Akikazu Matsumoto Daisuke Furukawa Hideyuki Nakazawa 《Journal of polymer science. Part A, Polymer chemistry》2006,44(17):4952-4965
We report the stereocontrol of diene polymers by the topochemical polymerization of alkoxy-substituted benzyl muconates in the solid state. A monomer stacking structure is controlled by the weak intermolecular interactions in the monomer crystals, depending on the structure and position of the alkoxy-substituent. The translational and alternating types of molecular stacking structures in a column provide diisotactic and disyndiotactic polymers, respectively, by the solid-state polymerization under UV and γ-ray irradiation. On the other hand, the meso and racemo structures of the resulting polymers are determined by the molecular symmetry of the used muconate monomers. The various substituted benzyl ester polymers are transformed into the same ethyl ester polymers with the four types of tacticities. The structure and crystallization behavior of the substituted benzyl ester polymers as well as the ethyl ester polymers have been revealed in detail. We clarify the effects of the tacticity on the crystallization property of the stereoregular polymuconates. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4952–4965, 2006 相似文献
5.
6.
Tasuku Nakajima Takayuki Kurokawa Hidemitsu Furukawa Qiu Ming Yu Yoshimi Tanaka Yoshihito Osada Jian Ping Gong 《高分子科学》1996,(1):1-9
Living tissues work with fantastic functions in soft and wet gel-like state. Thus, hydrogels have attracted much attention as excellent soft & wet materials, suitable for making artificial organs for medical treatments.However, conventional hydrogels are mechanically too weak for practical uses. We have created double network (DN) hydrogels with extremely high mechanical strength in order to overcome this problem. DN gels are interpenetrating network (IPN) hydrogels consisting of rigid polyelectrolyte and soft neutral polymer. Their excellent mechanical properties cannot be explained by the standard fracture theories. In this paper, we discuss about the toughening mechanism of DN gels in accordance with their characteristic behavior, such as large hysteresis and necking phenomenon. We also describe the results on tissue engineering application of DN gels. 相似文献
7.
I. Kunugiyama N. Ito T. Ishida S. Suzuki Y. Katoh Y. Furukawa 《Journal of Radioanalytical and Nuclear Chemistry》1992,165(5):309-317
Bromine and chlorine concentrations in some tissues (liver, spleen, thymus) of healthy mice (normal group) and lymphomatous mice (lymphoma group) were determined by neutron activation analysis. There were significant differences in the Br concentrations of the tissues between the normal and lymphomatous group, while the Cl concentrations were found relatively constant in all the tissues. As a result, the Br/Cl ratios in the tissues of the lymphomatous group were significantly higher than those of the normal group. It was difficult to conclude that Br was absorbed into the bodies of lymphomatous mice more easily than was Cl. It is suggested that Br excretion from the body is suppressed. 相似文献
8.
9.
Junji Furukawa Eiichi Kobayashi Morio Nakamura 《Journal of polymer science. Part A, Polymer chemistry》1974,12(12):2789-2799
The effect of ultraviolet irradiation on the terpolymerization was investigated. In the terpolymerizations of sulfur dioxide–butene-1–acrylonitrile, sulfur dioxide–butene-1–n-butyl acrylate, and maleic anhydride–allyl chloride–acrylonitrile systems, the composition of the terpolymers prepared under ultraviolet irradiation was different from those prepared in the dark. The unit content of sulfur dioxide and butene-1 or of maleic anhydride and allyl chloride in the terpolymer increased under ultraviolet irradiation. The nature of the growing end under ultraviolet irradiation is supposed to be the same as that of the dark polymerization on the basis of the same solvent effect on the terpolymer composition, the rate of polymerization and the molecular weight of polymer. The experimental results suggest that the complex between sulfur dioxide and butene-1 or maleic anhydride and allyl chloride might be excited by ultraviolet light and the excited complex may participate in the terpolymerization. 相似文献
10.
Functional poly(ethylene oxide) star polymers possessing a tertiary amino group at each arm end were prepared by free-radical copolymerization of poly(ethylene oxide) macromonomers with divinylbenzene (DVB) in water or ethanol. The poly(ethylene oxide) arm was prepared by anionic polymerization using 2-[2-(N,N-dimethylamino)ethoxy]ethanol potassium alkoxide as the initiator. The star polymers had narrow molecular weight distribution. The arm number was controlled by varying the feed ratio [DVB]/[M], the initial concentration of macromonomer [M], and solvent media. The branching factor g' in methanol ([eta]S/[eta]L are the intrinsic viscosities of the star and linear molecules, respectively) exhibited a power-law dependence on the arm number, f, with a negative exponent. This means that the dimensions of a star were in agreement with the Daoud-Cotton scaling model. 相似文献