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991.
Production of no-carrier-added 64Cu and applications to molecular imaging by PET and PETIS as a biomedical tracer 总被引:1,自引:0,他引:1
S. Watanabe Y. Iida N. Suzui T. Katabuchi S. Ishii N. Kawachi H. Hanaoka S. Watanabe S. Matsuhashi K. Endo N. S. Ishioka 《Journal of Radioanalytical and Nuclear Chemistry》2009,280(1):199-205
Copper-64 was produced by the 64Ni(p, n)64Cu reaction using enriched 64NiO target. We investigated and compared the production yield of 64Cu for proton beams of various energies by using a thick target. Enriched 64Ni was recovered with high yield by simple procedures. Imaging studies using positron emission tomography (PET) and positron
emitting tracer imaging system (PETIS) were performed. We obtained clear images in PET and PETIS studies. The results of this
study indicate that 64Cu can be utilized as a biomedical tracer for the molecular imaging both in animals and plants. 相似文献
992.
Bis(azafulvene) derivative of gem-dimethyldipyrrylmethane reacted with 2,2′-bipyrrole under neutral conditions without catalyst to give a mixture of expanded isocorroles in ca. 50% total yields. GPC separation gave eleven porphyrinoids containing 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, and 44 units of pyrrole. 相似文献
993.
Y Kobayashi M. K. Kubo Y. Yamada T. Saito H. Ueno H. Ogawa W. Sato K. Yoneda H. Watanabe N. Imai H. Miyoshi K. Asahi 《Journal of Radioanalytical and Nuclear Chemistry》2003,255(3):403-406
In-beam Mössbauer spectra of 57Fe, decayed from short-lived 57Mn (T1/2 = 1.45 min) implanted into potassium permanganate, KMnO4, were measured at temperatures between 11 K and 130 K. This is the first application of a secondary RI beam to the study of valence states after nuclear transformation. The in-beam Mössbauer spectra obtained below 90 K could be analyzed with two components, a doublet and a singlet. From the calculations of the molecular orbital wave functions, the singlet is suggested to be substitutional 57Fe atoms for Mn-sites in tetrahedral [MnO4]– with an unusually high valence state of Fe8+. 相似文献
994.
在GdBCO超导块材的熔融织构生长过程中施加10T强磁场,通过SEM研究强磁场对Gd2BaCuO5(Gd211)颗粒的影响.研究发现棒状Gd211颗粒在强磁场的作用下发生了择优取向——Gd211颗粒的长边与磁场方向平行.延长样品处于熔融状态的时间,发现Gd211颗粒的取向性明显增加.通过分析熔融织构的相变过程,结合磁取向能的公式,讨论了取向性增加的原因.同时,探讨了Gd211颗粒的择优取向对样品的超导性能产生的影响. 相似文献
995.
N. Watanabe H. Shiromaru Y. Negishi Y. Achiba N. Kobayashi Y. Kaneko 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,26(Z1):252-254
Reactions of carbon clusterions with O2 were studied by using an RF ion trap in which cluster ions of specific size produced by laser ablation could be stored selectively. Reaction rate constants for positive and negative carbon cluster ions were estimated. In the case of the positive cluster ions, these were consistent with the previous experimental results using FTMS. Negative carbon cluster ions C
n
–
(n=4–8) were much less reactive than positive cluster ions. The CnO– products were seen only in n=4 and 6. 相似文献
996.
997.
998.
R. Seki M. Watanabe K. Kurihara 《Journal of Radioanalytical and Nuclear Chemistry》2000,243(2):383-386
The amount of long-lived radioiodine, 129I (half-life 1.57·107 y) in the Japanese environment has been studied by measuring thyroids of humans and animals. The collected samples were thyroids of (1) humans in Ibaraki Prefecture, in Kanto district, the central part of Japan, (2) cattle in Aomori Prefecture, north part of Japan, and (3) wild deer in Chiba Prefecture, in Kanto district. The measured mean isotopic ratio 129I/127I for thyroids of cattle in Aomori Prefecture is 3.5±1.8·10-9. A higher value of 14±5·10-9 has been obtained for thyroids of wild deer in Kanto district. On the other hand, the measured ratio for human thyroids in Kanto district is 1±0.2·10-9. This value is significantly lower than that of cattle thyroids in Aomori and also those reported for human thyroids in Europe and USA. The higher mean ratio for cattle thyroid in Kanto district is possibly explained by the influence of nuclear reprocessing plant. Lower mean ratio for human thyroid might be due to higher dietary intake of algae. 相似文献
999.
P. Christopher Selvin S. Watanabe J. S. Ayala-Arenas 《Radiation Physics and Chemistry》2001,61(3-6):531-533
The natural mineral chrysocolla (CuSiO3·2H2O) has been investigated in terms of thermally stimulated luminescence and EPR measurements. The glow curves for natural samples present three glow peaks at 190, 357 and 450°C. Pre annealed and subsequently irradiated samples give rise to four glow peaks at 140°C, 193°C, 305°C and 450°C. The formation of Ho centers at the expense of water molecules present in the channels has been identified by EPR measurements. 相似文献
1000.
Hiroshi Watanabe Tomohiro Sato Kunihiro Osaki Mutsuo Matsumoto Dobrin P. Bossev Cathy E. McNamee Masaru Nakahara 《Rheologica Acta》2000,39(2):110-121
Linear viscoelastic behavior was investigated for aqueous solutions of perfluorooctyl sulfonate (C8F17SO−
3; abbreviated as FOS) micelles having a mixture of tetraethylammonium (N+(C2H5)4; TEA) and lithium (Li+) ions as the counter-ions. The solutions had the same FOS concentration (0.1 mol l−1) and various Li+ fractions in the counter-ions, φLi = 0−0.6, and the FOS micelles in these solutions formed threads which further organized into dendritic networks. At T ≤ 15 °C,
the terminal relaxation time τ and the viscosity η, governed by thermal scission of the networks, increased with increasing
φLi up to 0.55. A further increase of φLi resulted in decreases of τ and η and in broadening of the relaxation mode distribution. These rheological changes are discussed
in relation to the role of TEA ions in thermal scission: Previous NMR studies revealed that only a fraction of TEA ions were
tightly bound to the FOS micellar surfaces and these bound ions stabilized the thread/network structures. The concentration
of non-bound TEA ions, CTEA
*, decreased and finally vanished on increasing φLi up to φLi
* ≅ 0.6, and the concentration of the bound TEA ions significantly decreased on a further increase of φLi. The non-bound TEA ions appeared to catalyze the thermal scission of the FOS threads, and the observed increases of τ and
η for φLi < 0.55 were attributed to the decrease of CTEA
*. On the other hand, the decreases of τ and η as well as the broadening of the mode distribution, found for φLi > 0.55 (where CTEA
* ≅ 0), were related to destabilization of the FOS threads/networks due to a shortage of the bound TEA ions and to the existence
of concentrated Li+ ions. Viscoelastic data of pure FOSTEA and FOSTEA/FOSLi/TEACl solutions lent support to these arguments for the role of TEA
ions in the relaxation of FOSTEA/FOSLi solutions.
Received: 12 October 1999/Accepted: 1 November 1999 相似文献