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排序方式: 共有533条查询结果,搜索用时 15 毫秒
91.
92.
Takashi Uemura Nobuyuki Okuda Hiroya Kirmura Yasuko Okuda Yoshinobu Ueba Tuguru Shirakawa 《先进技术聚合物》1997,8(7):437-442
Electroluminescent(EL) devices have been fabricated using four different polymers with different glass transition temperatures (Tg) dispersed with N,N′-bis-(3-methylphenyl)-N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine (TPD) as a hole transport layer and tris(8-hydroxyquinoline) aluminum (Alq3) as an emitting layer. It was found that the higher the Tg of the polymer, the longer the lifetime of the device. From observations of TPD-doped polymer films with optical microscope and atomic force microscope, dispersing TPD in the polymers was found to suppress the crystallization that causes the roughness of the film surface. It was also observed that the higher the Tg of the host polymers, the more difficult TPD crystallization was. The property of the EL device with polyethersulfone (PES) dispersed with TPD was also investigated. The lifetime of EL device with the TPD doped PES film was improved more than five times at a current density below 10 mA/cm2 compared with the device with a conventional TPD hole transport layer. © 1997 John Wiley & Sons, Ltd. 相似文献
93.
Hyoe Hatakeyama Takanori Yoshida Yoshinobu Izuta Shigeo Hirose Tatsuko Hatakeyama 《Macromolecular Symposia》1999,144(1):313-321
Cellulose-based polycaprolactone (CAPCL) sheets were prepared from cellulose acetate (CA) and ϵ-caprolactone (CL). Thermal properties of the obtained CAPCL's were studied by differential scanning calorimetry (DSC), thermogravimetry (TG) and TG-Fourier transform infrared spectrometry (TG-FTIR). The glass transition temperatures (Tg 's) of CAPCL decreased with increasing CL/OH ratio, until CL/OH ratio reached 15 and then increased above that ratio. Melting of CAPCL was observed when CL/OH ratio was over 10. The thermal degradation temperatures (Td 's) of CAPCL increased from ca. 350 °C to 390 °C with increasing CL/OH ratio. The results obtained by TG-FTIR analysis of CAPCL showed that gases with OH, CH, C=O, C-O-C groups evolved by thermal degradation. 相似文献
94.
95.
Phase behaviors of argon in several types of cylindrical and slit pores are examined by grand-canonical Monte Carlo simulations. Condensation processes in single- and multi-walled carbon nanotubes along with those in hard-wall tubes are compared. Effects of the pore size on pressure-tensor components, the fluid-wall surface tension, and the adsorption are also compared for the different fluid-pore interactions. The chemical potential at which the fluid begins to condense in the single-walled nanotube is greater than that in the multi-walled nanotube by an amount nearly equal to the difference in the potential-well depth of the fluid-pore interaction, and the adsorption isotherms overlap each other almost completely for narrow pores and partially for wider pores. Similar analyses are performed for slit pores of two different hydrocarbon models. 相似文献
96.
The electrochemical reduction of nitric oxide in the presence of the excess oxygen was reviewed. It was shown that the selectivity
and activity of the cathodes is strongly dependent on the composition and on the microstructure of the cathode material. A
concept of electrochemical reactor with multilayer electro-catalytic electrode was proposed and successfully designed in Advanced
Manufacturing Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Nagoya, Japan.
The typical values of current efficiency in such electrochemical reactors are of the order of 10–20% at gas composition: 1,000 ppm
NO and 2% O2 balanced in He and at gas flow rate 50 ml/min. The value of current efficiency depends on the functional multi-layer electrode
composition, structure, and operating temperature. Such electrochemical reactors show the value of NO/O2 selectivity (ν
sel) higher than 5 (ν
sel > 5) at intermediate temperature and up to ν
sel = 25 at low temperature operation. It was shown that multilayer electro-catalytic electrode should consist at list from three
main functional layers: cathode, electro-catalytic electrode, covering layer, in order to operate as an electrode with high
selectivity. 相似文献
97.
Yoshiteru Akezaki Shunichi Yasuda Katumi Hamaoka Yoshinobu Yoshimoto Susumu Yoshimura Takuo Nomura Hiroshi Yamasaki Atushi Sato 《Physical Therapy Research》2009,12(1):9-12
Purpose: The obstacle negotiation gait (ONG) is a fundamental activity of daily living. In cerebrovascular hemiplegic patients (stroke patients), the weight-bearing rate (WBR) on the paretic limb necessary for an independent ONG was studied. Methods: One hundred and seventeen stroke patients were involved. The patients'' average age at the time of the study was 67 years, and the average time from stroke onset was 102 days. There were 68 men and 49 women. Seventy patients were right hemiplegics, and 47 were left hemiplegics. The correlations between ONG and age, sex, body mass index (BMI), time from stroke onset, muscle strength of both the paretic and non-paretic limbs, Brunnstrom stage of the lower limbs, deep sensation, and the WBR on both the paretic and non-paretic limbs were studied. Patients who could perform ONG independently and safely were categorized as the independent group (IG), and those who needed observation or any assistance were categorized as the dependent group (DG). Results: The BMI, muscle strength of both the paretic and non-paretic limbs, Brunnstrom stage of the lower limbs, deep sensation and the WBR for both the paretic and non-paretic limbs were significantly different between the IG and DG groups. In particular, the WBR on the paretic limb was found to correlate significantly with the ONG, and a WBR value of 80.5% on the paretic limb gave a clear cut-off value. Conclusion: Although multiple factors influenced the ONG of stroke patients, the WBR on the paretic limb was the most influential. 相似文献
98.
99.
K. Shiokawa 《Journal of mathematical chemistry》2009,45(1):175-187
Dynamical aspects of quantum Brownian motion in a low temperature environment are investigated. We give a systematic calculation
of quantum entanglement among two Brownian oscillators without invoking Born–Markov approximation widely used for the study
of open systems. Our approach is suitable to probe short time dynamics at cold temperatures where many experiments on quantum
information processing are performed. 相似文献
100.
Atsushi Goto Norihiro Hirai Yoshinobu Tsujii Takeshi Fukuda 《Macromolecular Symposia》2008,261(1):18-22
Summary : Phosphorus compounds were employed as catalysts in Reversible Chain Transfer Catalyzed Polymerization (RTCP), a novel class of living radical polymerization (LRP) which we had recently developed. Low-polydispersity polystyrene and poly(methyl methacrylate) with predicted molecular weights were obtained with a fairly high conversion in a fairly short time. These catalysts are particularly featured by their high reactivity hence small amounts being required, low toxicity, and low cost. Some phosphorus catalysts used in this work are among the least expensive catalysts/mediators of LRP developed so far. 相似文献