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101.
Power systems have become very large, and in addition the forthcoming open electricity market will make power system operation more complex. Therefore, power system operation must become more efficient and flexible. Very fast power system simulation is a means of achieving more sophisticated power system on‐line monitoring and control, and parallel computing is a key technology for very fast power system simulation. This paper proposes an efficient and fast parallel network calculation algorithm that will contribute to the development of fast power system simulation programs. Numerical examples show that the proposed method using six processors is about 4.0 times as fast as the usual serial algorithm when applied to a large‐scale radial power system and about 3.2 times as fast when applied to a large‐scale loop power system. © 2001 Scripta Technica, Electr Eng Jpn, 135(3): 26–36, 2001 相似文献
102.
Masaki Horie I.-Wen Shen Henry Leventis Jenny Nelson Michael L. Turner 《Polymer》2010,51(7):1541-11830
Poly(3,4-dioctylthienylenevinylene) (PDOTV) was synthesised by ring-opening metathesis polymerization (ROMP) with controlled molecular weight. PDOTV has been used to fabricate organic photovoltaic devices in combination with phenyl C61-butyric acid methyl ester (PCBM) for the first time. The devices show power conversion efficiency up to 0.18%. Optimal device performance was found at a film thickness of 100 nm and a ratio of PCBM to PTV of 2:1. External quantum efficiency (EQE) measurements, transient absorption spectroscopy and morphology studies were carried out to establish factors governing photovoltaic performance. These results suggest that the efficiency values for the devices were limited by the hole mobility and unexpected phase separation within the blend. Nevertheless, the results show that ROMP is a viable, alternative, synthetic strategy for preparing PTV donors for use in bulk heterojunction OPVs. 相似文献
103.
Masamichi Kajita Masaki MagariKagefumi Todo Naoki KanayamaHitoshi Ohmori 《Journal of Bioscience and Bioengineering》2010,109(4):407-410
A hypermutating B cell line DT40 is useful for screening antibodies and improving affinity of the selected antibodies in vitro. To perform affinity maturation efficiently, we generated an engineered DT40 line whose immunoglobulin mutation pattern can be transformed from gene conversion into point mutation by conditional suppression of XRCC3 expression. 相似文献
104.
Takami Kai Norihide Okada Manabu Baba Takeshige Takahashi Masaki Misawa Ion Tiseanu Naoki Ichikawa 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2007,130(2-3):119-124
In a fluidized catalyst bed, the reactant gas transfers from the bubble phase to the emulsion phase and reactions proceed in the emulsion phase. The catalyst particles around the bubbles should contact the gases containing a high concentration of the reactants. Therefore, the effect of the catalysts around the bubbles is very important for estimating the conversion and selectivity in the reactor. In order to study the role of these catalysts, the hydrogenation of carbon dioxide was carried out in a fluidized catalyst bed. Based on the results, the amount of the catalyst that was effective for the reaction was calculated. In addition, the shape of the bubbles ascending in the fluidized catalyst bed was observed using a fast X-ray computer tomography (CT) scanner. The structure of the bubbles in the fluidized catalyst bed was very complicated and the surface area of the bubbles was much greater than the obtained when assuming spherical shaped bubble. By assuming that effective catalysts existed around the bubbles, the thickness of catalyst layer was obtained. Finally, the 3-dimensional images of the catalyst layers around the bubbles were reconstructed. 相似文献
105.
Tomoyuki Kawase Kazuhiro Okuda Hiroyuki Kogami Hitoshi Nakayama Masaki Nagata Hiromasa Yoshie 《Journal of materials science. Materials in medicine》2010,21(2):731-739
Our animal implantation studies have demonstrated that, after osteogenic processing, cultured human periosteal sheets form
osteoid tissue ectopically without the aid of conventional scaffolding materials. To improve the osteogenic activity of these
periosteal sheets, we have tested the effects of including a scaffold made of salmon collagen-coated ePTFE mesh. Periosteal
sheets were produced with minimal manipulation without enzymatic digestion. Outgrown cells penetrated into the coated mesh
fiber networks to form complex multicellular layers and increased expression of alkaline phosphatase activity in response
to the osteoinduction. In vitro mineralization was notably enhanced in the original tissue segment regions, but numerous micro-mineral
deposits were also formed on the coated-fiber networks. When implanted subcutaneously into nude mice, periosteal sheets efficiently
form osteoid around the mineral deposits. These findings suggest that the intricate three-dimensional mesh composed of collagen-coated
fibers substantially augmented the osteogenic activity of human periosteal sheets both in vitro and in vivo. 相似文献
106.
107.
LiMxMn2−xO4 (M=Co, Ni) materials have been synthesized by a melt-impregnation method using γ-MnOOH as the manganese source. Highly crystallized LiMxMn2−xO4 compounds were synthesized at a calcination temperature of 800°C for 24 h in air. All compounds show a single phase except for LiNi0.5Mn1.5O4 based on the X-ray diffraction (XRD) diagram. With the increase of the doping content from 0.1 to 0.5, the capacity of doping materials decreases mainly in the 4 V region.
Although LiM0.5Mn1.5O4 (M=Co, Ni) compound shows a small capacity in the (3+4) V region compared with parent LiMn2O4, it is a very effective material in reducing capacity loss in the 3 V region that is caused by the Jahn–Teller distortion. The doping of Co and Ni ions in the LiMn2O4 cathode material promotes the stability of this structure and provides an excellent cyclability. 相似文献
108.
T Komuro S Miwa XF Zhang T Minowa T Enoki S Kobayashi Y Okamoto H Ninomiya T Sawamura K Kikuta Y Iwamuro H Furutani H Hasegawa Y Uemura H Kikuchi T Masaki 《Canadian Metallurgical Quarterly》1997,30(4):504-509
The alpha-amylase of Streptomyces sp. IMD 2679 was subject to catabolite repression. Four different growth rates were achieved when the organism was grown at 40 degrees C and 55 degrees C in the presence and absence of cobalt, with an inverse relationship between alpha-amylase production and growth rate. Highest alpha-amylase yields (520 units/ml) were obtained at the lowest growth rate (0.062 h-1), at 40 degrees C in the absence of cobalt, while at the highest growth rate (0.35 h-1), at 55 degrees C in the presence of cobalt, alpha-amylase production was decreased to 150 units/ml. As growth rate increased, the rate of specific utilisation of the carbon source maltose also increased, from 46 to 123 micrograms maltose (mg biomass)-1 h-1. The pattern and levels of alpha-glucosidase (the enzyme degrading maltose) detected intracellularly in each case, indicate that growth rate effectively controls the rate of feeding of glucose to the cell, and thus catabolite repression. 相似文献
109.
110.
Hideki Taguchi Katsuyuki Nakade Masashi Yosinaga Masaki Kato Ken Hirota 《Journal of the American Ceramic Society》2008,91(1):308-310
X-ray photoelectron spectroscopy was performed to elucidate the catalytic activity of CH4 oxidation on perovskite-type Ca(Mn1− x Ti x )O3−δ synthesized at 1173 K in a flow of oxygen from a gel with citric acid and ethylene glycol. The Mn ion content decreases and the ratio of the Mn3+ ion in the Mn ion increases with increases in x . Ca(Mn1− x Ti x )O3−δ has a high catalytic activity of CH4 oxidation at x =0.4. These results indicate that the catalytic activity strongly depends on the Mn3+ ion content of the surface. 相似文献