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991.
Hiroharu Ajiro Yoshikazu Takahashi Mitsuru Akashi Tomoko Fujiwara 《Macromolecular bioscience》2012,12(10):1315-1320
Novel block copolymers using the monomers 5‐(2‐methoxyethyoxymethyl)‐5‐methyl‐[1,3]‐dioxa‐2‐one (TMCM‐MOE1OM) as a hydrophilic segment and lactides as a hydrophobic segment were designed in order to prepare controllable degradation polymers by dynamic polymer rearrangement based on the hydrophilicity. When the copolymer film contacted water, the hydrophobic polylactide (PLA) segments tend to be buried under the TMCM‐MOE1OM segments due to the hydrophilicity of the methoxyethoxy groups. The copolymers were hardly degraded by both proteinase K and lipase, while both of their homopolymers, poly(trimethylene carbonate) and PLA, were degraded, which suggests that the rearrangement of the TMCM‐MOE1OM segments at the outermost surface significantly improved the degradation ratio.
992.
993.
Hirokazu Masai Toshiro Tanimoto Takumi Fujiwara Syuji Matsumoto Yoshihiro Takahashi Yomei Tokuda Toshinobu Yoko 《Journal of Non》2012,358(2):265-269
The authors investigate the structural change of a ZnO–P2O5 sintered matrix for the preparation of SnO-doped zinc phosphate (SZP) glass using a platinum crucible. Heat treatment of zinc oxide and ammonium phosphate at 800 °C causes the formation of a Zn2P2O7-like species, which is effective in preventing damage to the platinum crucible. Although the thermal property of the glass was affected by added Al2O3, Al2O3 hardly affects the quantum efficiency of the SZP glass phosphor. This process is important for the fabrication of contamination-free phosphate glass using ammonium phosphate as a starting material. 相似文献
994.
Carefully designed indentation creep experiments and detailed finite-element computations were carried out in order to establish a robust and systematic method to extract creep properties accurately during indentation creep tests. Samples made from an Al–5.3?mol%?Mg solid-solution alloy were tested at temperatures ranging from 573 to 773?K. Finite-element simulations confirmed that, for a power-law creep material, the indentation creep strain field is indeed self-similar in a constant-load indentation creep test, except during short transient periods at the initial loading stage and when there is a deformation mechanism change. Self-similar indentation creep leads to a constitutive equation from which the power-law creep exponent n, the activation energy Q c for creep, the back or internal stress and so on can be evaluated robustly. The creep stress exponent n was found to change distinctively from 4.8 to 3.2 below a critical stress level, while this critical stress decreases rapidly with increasing temperature. The activation energy for creep in the stress range of n = 3.2 was evaluated to be 123?kJ?mol?1, close to the activation energy for mutual diffusion of this alloy, 130?kJ?mol?1. Experimental results suggest that, within the n = 3.2 regime, the creep is rate controlled by viscous glide of dislocations which drag solute atmosphere and the back or internal stress is proportional to the average applied stress. These results are in good agreement with those obtained from conventional uniaxial creep tests in the dislocation creep regime. It is thus confirmed that indentation creep tests of Al–5.3?mol%?Mg solid-solution alloy at temperatures ranging from 573 to 773?K can be effectively used to extract material parameters equivalent to those obtained from conventional uniaxial creep tests in the dislocation creep regime. 相似文献
995.
Katsuyuki Morishita Hiroshi Karasuno Yuka Yokoi Kazunori Morozumi Hisayoshi Ogihara Toshikazu Ito Takayuki Fujiwara Tetsuya Fujimoto Koji Abe 《Physical Therapy Research》2014,17(1):1-7
Purpose: This study aimed to clarify the effects of therapeutic ultrasound on intramuscular local blood circulation (and oxygen dynamics) using near-infrared spectroscopy (NIRS). Participants: The participants were 11 healthy males. Methods: All participants performed all three trials; (1) the ultrasound (US group), (2) without powered ultrasound (placebo group), and (3) rest (control group). Ultrasound was applied at 3 MHz, 1.0 W/cm2, and 100% duty cycle for 10 minutes. Evaluation index were oxygenated, deoxygenated, and total hemoglobin (Hb) concentrations in the intramuscular and skin surface temperature (SST). The experimental protocol was a total of 40 minutes, that is, 10 minutes before trial (rest), 10 minutes during the trial (ultrasound, placebo, and control), and 20 minutes after trial (rest). The NIRS and SST data collected before and after the trial were divided into 5 minutes intervals for further analysis. Results: Oxygenated and total hemoglobin levels were significantly higher in the US group than in the placebo and control groups for the 20 minutes after ultrasound (p < 0.01). The SST was significantly higher in the US group than in the control for 15 minutes after ultrasound (p < 0.05), while it was significantly lower in the placebo group than in the US and control groups for 20 minutes after the trials (p < 0.01). Conclusion: The effects of ultrasound were maintained for 20 minutes after the trial on intramuscular blood circulation and oxygen dynamics. These effects were caused by a combination of thermal and mechanical effects of the ultrasound. 相似文献
996.
Shoichi Kondo Masayuki Ishikawa Masakazu Fujiwara Isamu Ono Shigeru Mita 《Molecular Crystals and Liquid Crystals》2013,570(1):777-784
Abstract The orientational order parameters of six solutes with different shapes and sizes dissolved in two nematic solvents have been measured as a function of temperature. The parameter, Sxx-Syy is correlated with the molecular geometrical structure, while Szz is affected by not only the geometry but also the anisotropy in the polarizability. The molecular dynamics simulations are carried out using a realistic atom-atom potential for evaluating the ordering properties in the nematic phase. The results provide reasonable values of Szz corresponding to experimental ones for solutes and solvents, and also a prediction of uniaxiality for the nematic phase. 相似文献
997.
We have examined the neutron-deuteron low-energy effective-range parameters, differential cross sections and spin polarization observables of the elastic nucleon-deuteron scattering up to the incident nucleon energy E N = 65 MeV, using the quark-model nucleon–nucleon interaction fss2. These observables are consistently described without introducing three nucleon forces except for the nucleon analyzing power A y (θ) and the deuteron vector analyzing power iT 11(θ) in the low-energy region E N ≤ 25 MeV. The long-standing A y puzzle is slightly improved, but still remains. We have incorporated the screened Coulomb force to the proton-deuteron scattering, modifying the Vincent–Phatak approach for the sharp cutoff Coulomb force. The Coulomb effect on the elastic scattering observables is discussed. 相似文献
998.
Naoko Fujiwara Shin-ichi Yamazaki Zyun Siroma Tsutomu Ioroi Hiroshi Senoh Kazuaki Yasuda 《Electrochemistry communications》2009,11(2):390-392
Nonenzymatic glucose fuel cells were prepared by using a polymer electrolyte membrane and Pt-based metal catalysts. A fuel cell with a cation exchange membrane (CEM), which is often used for conventional polymer electrolyte fuel cells, shows an open circuit voltage (OCV) of 0.86 V and a maximum power density (Pmax) of 1.5 mW cm?2 with 0.5 M d-glucose and humidified O2 at room temperature. The performance significantly increased to show an OCV of 0.97 V and Pmax of 20 mW cm?2 with 0.5 M d-glucose in 0.5 M KOH solution when the electrolyte membrane was changed from a CEM to an anion exchange membrane (AEM). This is due to the superior catalytic activity for both glucose oxidation and oxygen reduction in alkaline medium than in acidic medium. The anodic reaction of the fuel cell can be estimated to be the oxidation of glucose to gluconic acid via a two-electron process under these experimental conditions. The crossover of glucose through an electrolyte membrane was negligibly small compared with methanol and may not represent a serious technical problem due to the cross-reaction. 相似文献
999.
Masako Fujiwara Takeshi Kobayashi Takahiro Jomori Yutaka Maruyama Yoshitomo Oka Hiroshi Sekino Yutaka Imai Kazuhisa Takeuchi 《Analytical and bioanalytical chemistry》2009,394(6):1655-1660
1H NMR spectroscopic and pattern recognition-based methods (NMR-PR) were applied to the metabolic profiling studies on hemodialysis
(HD). Plasma samples were collected from 37 patients before and after HD and measured by 600 MHz NMR spectroscopy. Each spectrum
was data-processed and subjected to principal component analysis for pattern recognition. Spectral patterns of plasma between
pre- and post-dialyses were clearly discriminated, together with significant fluctuations in the levels of creatinine, trimethylamine-N-oxide, glucose, lactate, and acetate, which were quantitated. We have first observed the significant elevation of lactate
levels in post-dialysis plasma. The present study has demonstrated the high feasibility of NMR-PR method for monitoring the
dialysis condition and comprehensive profiling of the change of low-molecular-weight metabolites in HD.
Figure PCA for 1H NMR spectra of plasma from HD patients 相似文献
1000.
Kenzo Kubota Yuya Ozaki Yoshiki Matsumiya Motoki Kubo 《Applied biochemistry and biotechnology》2009,158(3):493-501
To analyze the relationship between biomass of microorganisms and methane production, the total biomass of bacteria and archaea
(BA) during methane fermentation was analyzed by the environmental DNA analysis method. In the case of using methanogenic
sludge as a seed which is generally used for methane fermentation, the total BA biomass reached to 1.5 × 108 to 3.6 × 108 cells/ml when methane was produced. On the other hand, soil suspension was used as a seed; methane was not produced for 14-day
cultivation. However, the total BA biomass reached to above 1.5 × 108 cells/ml. The methanogen biomass was counted by using a fluorescence microscope (coenzyme F420), and the methanogen biomass and the ratio of methanogens in the total of BA were analyzed during methane fermentation. At
the methane-producing phase, the methanogen biomass reached to 1.3 × 108 cells/ml, and the ratio of methanogens was above 70% of the total BA. When the ratio of methanogens in a seed was changed,
the methane-producing phase was moved. However, the relationship between methanogens and other microorganisms at the methane-producing
phase was almost similar. 相似文献