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121.
Journal of Radioanalytical and Nuclear Chemistry - Decreasing trends of both 137Cs and 3H activity concentrations and an increasing trend of 3H/137Cs activity ratio at Fukushima Dai-ichi Nuclear... 相似文献
122.
123.
Kazufumi KITAGAKI Rei ONO Harumi KONISHI Michio NAKANISHI Hiroyuki MIURA Tatsuo AOKI Teruo NOGUCHI 《Physical Therapy Research》2022,25(3):106
Objective: This study aimed to investigate whether longitudinal changes in exercise capacity in patients with acute myocardial infarction (AMI) differ by sex and clarified what contributed to these differences. Methods: We retrospectively examined the differences in each variable between men and women in 156 patients with AMI (mean age: 65 ± 12 years; 82.0% male) who participated in a 3-month cardiac rehabilitation (CR) program and could be followed-up for exercise capacity 12-months after AMI onset. Sex-related differences in the change in peak oxygen uptake (peak VO2) at baseline, 3-months, and 12-months after AMI were analyzed. Results: Male patients with AMI were younger and had higher body mass index and employment rate than women. The attendance of the CR program was higher in women (men vs. women; 10 [3–15] vs. 14 [11–24] sessions, p = 0.0002). Women showed a significant lower %change in peak VO2 after 12 months (men vs. women; 7.8% [–0.49% to 14.6%] vs. 1.3% [–5.7% to 7.5%], p = 0.013). In multiple linear regression analysis, age (β = –0.76, 95% confidence interval [CI] = –1.0 to –0.50, p <0.0001) and female sex (β = –6.3, 95% CI = –9.1 to –3.5, p <0.0001) were negative independent predictors of change in peak VO2 over 12 months, while CR attendance (β = 0.21, 95% CI = 0.0032–0.42, p = 0.047) and recommended exercise habit after the CR program (β = 2.1, 95% CI = 0.095–4.1, p = 0.040) were positive independent predictors of change in peak VO2 over 12 months. Conclusion: In female patients, exercise capacity improved during the CR program but decreased to AMI onset levels after 12 months. 相似文献
124.
Stereoselective synthesis of the chemoattractant sperm-activating and attracting factor (SAAF), isolated from the eggs of the ascidian Ciona intestinalis, was achieved via reductive 1,3-transposition of an allylic alcohol and the axial opening of an epoxide as key steps. This second-generation synthesis improved the total yield of SAAF over that of the first-generation synthesis and provided a key intermediate for synthesizing molecular probes of SAAF. 相似文献
125.
Ryugo S. HAYANO Masaharu TSUBOKURA Makoto MIYAZAKI Akihiko OZAKI Yuki SHIMADA Toshiyuki KAMBE Tsuyoshi NEMOTO Tomoyoshi OIKAWA Yukio KANAZAWA Masahiko NIHEI Yu SAKUMA Hiroaki SHIMMURA Junichi AKIYAMA Michio TOKIWA 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2015,91(8):440-446
BABYSCAN, a whole-body counter (WBC) for small children was developed in 2013, and units have been installed at three hospitals in Fukushima Prefecture. Between December, 2013 and March, 2015, 2707 children between the ages of 0 and 11 have been scanned, and none had detectable levels of radioactive cesium. The minimum detectable activities (MDAs) for 137Cs were ≤3.5 Bq kg−1 for ages 0–1, decreasing to ≤2 Bq kg−1 for ages 10–11. Including the 134Cs contribution, these translate to a maximum committed effective dose of ∼16 µSv y−1 even for newborn babies, and therefore the internal exposure risks can be considered negligibly small.Analysis of the questionnaire filled out by the parents of the scanned children regarding their families’ food and water consumption revealed that the majority of children residing in the town of Miharu regularly consume local or home-grown rice and vegetables, while in Minamisoma, a majority avoid tap water and produce from Fukushima. The data show, however, no correlation between consumption of locally produced food and water and the children’s body burdens. 相似文献
126.
Oxidation of Cu3Au(1 1 0) using a hyperthermal O2 molecular beam (HOMB) was investigated by X-ray photoemission spectroscopy in conjunction with a synchrotron light source. From the incident energy dependence of the O-uptake curve, the precursor-mediated dissociative adsorption occurs, where the trapped O2 molecule can migrate and dissociate at the lower activation-barrier sites, dominantly at thermal O2 exposures. Dissociative adsorption of O2 on Cu3Au(1 1 0) is as effective at the thermal O2 exposure as on Cu(1 1 0). On the other hand, at the incident energies of HOMB where the direct dissociative adsorption is dominant, it was determined that the dissociative adsorption of O2 implies a higher activation barrier and therefore less reactivity due to the Au alloying in comparison with the HOMB oxidation of Cu(1 1 0). The dissociative adsorption progresses with the Cu segregation on Cu3Au(1 1 0) similarly as on Cu3Au(1 0 0). The growth of Cu2O for 2 eV HOMB suggests that the diffusion of Cu atoms also contribute to the oxidation process through the open face, which makes the difference from Cu3Au(1 0 0). 相似文献
127.
Synthesis of a 6/6/6 tricyclic ether system (3) corresponding to the ABC ring fragment of yessotoxin (1) has been achieved via coupling of a triflate and a 2-lithiofuran followed by intramolecular hetero-Michael addition. The IJ ring fragment (4) of 1 was readily synthesized via successive Sharpless epoxidation and 6-endo cyclization of the resulting vinyl epoxide. 相似文献
128.
Negishi Y Tsunoyama H Suzuki M Kawamura N Matsushita MM Maruyama K Sugawara T Yokoyama T Tsukuda T 《Journal of the American Chemical Society》2006,128(37):12034-12035
We report herein the X-ray magnetic circular dichroism (XMCD) at the Au L2,3 edges of a series of Au clusters protected by glutathione (GSH). The samples used here included AuN(SG)M with (N, M) = (10, 10), (15, 13), (18, 14), (22, 16), (25, 18), (29, 20), (39, 24) and a sodium gold(I) thiomalate (SGT) as a reference. Magnetic moments per cluster were found to be increased with size, whereas those per Au-S bond were nearly constant. This finding suggests that a localized hole created by Au-S bonding at the gold/glutathione interface, rather than the quantum size effect, is responsible for the spin polarization of gold clusters. 相似文献
129.
The structure of a protein molecule is considered to be primarily determined by the inter-amino-acid nonbonded interactions, such as hydrogen bonds. However, the conformational space of the polypeptide chain should be simultaneously restricted by the intrinsic conformational preferences of the individual amino acids. We present here precise single amino acid potential (SAAP) surfaces for glycine (For-Gly-NH(2)) and alanine (For-Ala-NH(2)) in water (epsilon = 78.39) and ether (epsilon = 4.335), which were calculated at the HF/6-31+G(d,p) level applying the self-consistent isodensity polarizable continuum model (SCIPCM) reaction field with geometry optimization in the corresponding solvents. The obtained Ramachandran potential surfaces in water showed distinct potential wells in the alpha- and beta-regions. The profiles were in almost perfect agreement with the Ramachandran plots of glycine and alanine residues in folded proteins, suggesting the Boltzmann distributions on the SAAP surfaces. Molecular simulations of polyalanines (For-Ala(n)-NH(2); n = 3-5) by using the SAAP force field equipped with the SCIPCM potentials revealed that the polyalanines readily form 3(10)-helical structures in water but not in vacuo. In ether (hydrophobic environments), the helical structures were relatively stable, but the most stable structure was assigned to a different one. These results indicated that the intrinsic conformational preferences of the individual amino acids (i.e., the SAAPs) in water are of significant importance not only for describing conformations of a polypeptide chain in the random coil state but also for understanding the folding to the secondary and tertiary structures. 相似文献
130.
Yamada M Minowa M Sato S Kako M Slanina Z Mizorogi N Tsuchiya T Maeda Y Nagase S Akasaka T 《Journal of the American Chemical Society》2010,132(50):17953-17960
Thermal carbosilylation of endohedral dimetallofullerene La(2)@I(h)-C(80) with silirane (silacyclopropane) is reported herein for the first time. Two diastereomers of the carbosilylated La(2)@I(h)-C(80) have been isolated and characterized. The fascinating molecular structure of one diastereomer of the carbosilylated derivatives has been determined unambiguously using X-ray crystallographic analysis. Detailed characteristics of the molecular structures including their metal atom movements have also been revealed using NMR spectroscopic studies and computational calculations. Results revealed that two La atoms move dynamically inside the carbon sphere. Furthermore, electrochemical study has demonstrated that carbosilylation is effective to fine-tune the La(2)@I(h)-C(80) electronic properties. 相似文献