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111.
Keiji Uchiyama Hideyuki Hara Junji Chida Agriani Dini Pasiana Morikazu Imamura Tsuyoshi Mori Hanae Takatsuki Ryuichiro Atarashi Suehiro Sakaguchi 《International journal of molecular sciences》2021,22(21)
Prion diseases are a group of fatal neurodegenerative disorders caused by accumulation of proteinaceous infectious particles, or prions, which mainly consist of the abnormally folded, amyloidogenic prion protein, designated PrPSc. PrPSc is produced through conformational conversion of the cellular isoform of prion protein, PrPC, in the brain. To date, no effective therapies for prion diseases have been developed. In this study, we incidentally noticed that mouse neuroblastoma N2a cells persistently infected with 22L scrapie prions, termed N2aC24L1-3 cells, reduced PrPSc levels when cultured in advanced Dulbecco’s modified eagle medium (DMEM) but not in classic DMEM. PrPC levels remained unchanged in prion-uninfected parent N2aC24 cells cultured in advanced DMEM. These results suggest that advanced DMEM may contain an anti-prion compound(s). We then successfully identified ethanolamine in advanced DMEM has an anti-prion activity. Ethanolamine reduced PrPSc levels in N2aC24L1-3 cells, but not PrPC levels in N2aC24 cells. Also, oral administration of ethanolamine through drinking water delayed prion disease in mice intracerebrally inoculated with RML scrapie prions. These results suggest that ethanolamine could be a new anti-prion compound. 相似文献
112.
Bisanthracene‐Based Donor–Acceptor‐type Light‐Emitting Dopants: Highly Efficient Deep‐Blue Emission in Organic Light‐Emitting Devices
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Jian‐Yong Hu Yong‐Jin Pu Fumiya Satoh So Kawata Hiroshi Katagiri Hisahiro Sasabe Junji Kido 《Advanced functional materials》2014,24(14):2064-2071
Deep‐blue fluorescent compounds are particularly important in organic light‐emitting devices (OLEDs). A donor–accepotor (DA)‐type blue‐emitting compound, 1‐(10‐(4‐methoxyphenyl)anthracen‐9‐yl)‐4‐(10‐(4‐cyanophenyl)anthracen‐9‐yl)benzene ( BD3 ), is synthesized, and for comparison, a nonDA‐type compound, 1,4‐bis(10‐phenylanthracene‐9‐yl)benzene ( BD1 ) and a weak DA‐type compound, 1‐(10‐phenylanthracen‐9‐yl)‐4‐(10‐(4‐cyanophenyl)anthracen‐9‐yl)‐benzene ( BD2 ), are also synthesized. The twisted conformations of the two anthracene units in the compounds, confirmed by single crystal X‐ray analysis, effectively prevent π‐conjugation, and the compound shows deep‐blue photoluminescence (PL) with a high PL quantum efficiency, almost independent of the solvent polarity, resulting from the absence of an intramolecular charge transfer state. The DA‐type molecule BD3 in a non‐doped device exhibits a maximum external quantum efficiency (EQE) of 4.2% with a slight roll‐off, indicating good charge balance due to the DA‐type molecular design. In the doped device with 4,4′‐bis(N‐carbazolyl)‐1,1′‐biphenyl (CBP) host, the BD3 exhibits higher EQE than 10% with Commission International de L'Eclairge (CIE) coordinates of (0.15, 0.06) and a narrow full‐width at half‐maximum of 45 nm, which is close to the CIE of the high definition television standard blue. 相似文献
113.
Keiko Azuma Katsunari Ippoushi Hidekazu Ito Hisao Higashio Junji Terao 《Journal of the science of food and agriculture》1999,79(14):2010-2016
The antioxidative effects of vegetable extracts were evaluated using linoleic acid emulsion and liposomal phospholipid suspension systems. First, the antioxidative activities of water, ethanol and 2% metaphosphoric acid extracts of the vegetables were investigated by measuring the rate of oxygen consumption in the peroxidation of linoleic acid initiated by a radical generator, 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH), with a Clark electrode in the absence of metal chelators. Ethanol extracts of moroheiya and perilla exhibited the highest antioxidative activities. Without metal chelators, 12 ethanol extracts and one water extract acted as prooxidants, and this phenomenon could be attributed to the prooxidant action of ascorbic acid in the presence of free transition metal ions. Next, peroxyl radical-scavenging activities of vegetable extracts were examined by adding a metal chelator, diethylenetriaminepentaacetic acid (DTPA), to the linoleic acid emulsion system. The results were compared with their antioxidative activities in phospholipid bilayers by measuring the inhibition of lipid peroxidation in large unilamellar vesicles composed of egg yolk phosphatidylcholine (PC). A good correlation was observed between the antioxidative activities obtained from these two systems. The antioxidative activities in the liposomal phospholipid suspension system correlated with total contents of ascorbic acid and polyphenols in vegetable extracts. © 1999 Society of Chemical Industry 相似文献
114.
115.
This paper analyzes the effect of fuzzy logic-controlled superconductive magnetic energy storage (SMES) on minimizing shaft torsional oscillations of synchronous generators in a multi-machine power system. The proposed fuzzy logic controller has been designed in a very simple way considering only one input variable and one output variable. The time derivative of the total kinetic energy deviation (TKED) of the synchronous generators is used as the global input to the fuzzy controller for SMES switching. The influence of time delay associated with the global input calculation of the fuzzy controller on minimizing shaft torsional oscillations is investigated. Global positioning system (GPS) is proposed for the practical implementation of the calculation of the global input to the fuzzy controller. Simulation results of a balanced fault at different points in a multi-machine power system show that the proposed SMES can minimize the shaft torsional oscillations of synchronous generators well. Moreover, the time delay has an influence on the performance of fuzzy controlled SMES to minimize shaft torsional oscillations. However, even though the performance of fuzzy controlled SMES is somewhat effected by the communication delay, it is clear from the simulation responses that the fuzzy logic-controlled SMES considering typical communication delays can minimize the shaft torsional oscillations of synchronous generators well. 相似文献
116.
Daisuke Yokoyama Ken‐ichi Nakayama Toshiya Otani Junji Kido 《Advanced materials (Deerfield Beach, Fla.)》2012,24(47):6386-6386
117.
Nabeshi H Yoshikawa T Matsuyama K Nakazato Y Arimori A Isobe M Tochigi S Kondoh S Hirai T Akase T Yamashita T Yamashita K Yoshida T Nagano K Abe Y Yoshioka Y Kamada H Imazawa T Itoh N Kondoh M Yagi K Mayumi T Tsunoda S Tsutsumi Y 《Nanotechnology》2012,23(4):045101
We previously reported that well-dispersed amorphous nanosilicas with particle size 70 nm (nSP70) penetrate skin and produce systemic exposure after topical application. These findings underscore the need to examine biological effects after systemic exposure to nanosilicas. The present study was designed to examine the biological effects. BALB/c mice were intravenously injected with amorphous nanosilicas of sizes 70, 100, 300, 1000 nm and then assessed for survival, blood biochemistry, and coagulation. As a result, injection of nSP70 caused fatal toxicity, liver damage, and platelet depletion, suggesting that nSP70 caused consumptive coagulopathy. Additionally, nSP70 exerts procoagulant activity in vitro associated with an increase in specific surface area, which increases as diameter reduces. In contrast, nSP70-mediated procoagulant activity was absent in factor XII-deficient plasma. Collectively, we revealed that interaction between nSP70 and intrinsic coagulation factors such as factor XII, were deeply related to nSP70-induced harmful effects. In other words, it is suggested that if interaction between nSP70 and coagulation factors can be suppressed, nSP70-induced harmful effects may be avoided. These results would provide useful information for ensuring the safety of nanomaterials (NMs) and open new frontiers in biological fields by the use of NMs. 相似文献
118.
Gold nano-rod array membranes (Au-NRM) were prepared by modification of the template method. A simple two-electrode device was assembled by holding an electrolyte solution between the Au-NRM and a transparent electrode. Small reflectance changes (less than 2%) in the visible band were induced on the Au-NRM surface by applying a DC voltage to the device. These changes could be visually observed. It was found based on a further evaluation that the reflectance changes responded very fast (less than 100 ms) to the DC voltage application, and were stable during the switching repetition (over 5000 times). When the cyclic scanning of the applied voltage to the device was carried out between -1.5 V and +1.5 V, the reflectance changes were increased over +1.0 V (-1.0 V). It was suggested from these experimental results that the reflectance changes were attributed to the surface oxidation and the deformation or mechanical motion of the Au nano-rod. 相似文献
119.
Kenji TakadaYuta Ishigami Junji Inukai Yuzo NagumoHiroshi Takano Hiroyuki Nishide 《Journal of power sources》2011,196(5):2635-2639
Visualization inside polymer electrolyte fuel cells (PEFCs) is important for elucidating reaction distributions to improve the performance and durability of the cells. An O2-sensitive porphyrin luminescent dye film was used to visualize oxygen partial pressures and water blockages simultaneously in triple-serpentine gas flow channels in an operating PEFC. Water droplets formed near the exit of a gas-flow channel lowered the oxygen partial pressure noticeably over the channel by blocking air flow near the entrance. Meanwhile, air was continuously supplied from the other channels through the gas diffusion layer, thus allowing power to be generated in the blocked channel. With water blockages, however, the catalyst layer under the channel became flooded by the water produced during the reaction, and the flooded state continued to exist in the catalyst and/or porous layers, even after blowing the water droplet out, so that the power generation was lowered along the channel. 相似文献
120.
Shimada Y Chow LC Takagi S Tagami J 《Journal of research of the National Institute of Standards and Technology》2010,115(4):233-241
Previous studies reported premixed calcium phosphate cements (CPCs) that were stable in the package and form hydroxyapatite (HA) as the product after exposure to an aqueous environment. These cements had setting times of greater than 60 min, which are too long to be useful for some clinical applications. The present study investigated properties of fast-setting HA-forming premixed CPCs that initially consisted of two separate premixed pastes: (1) finely ground (1.0 μm in median size) dicalcium phosphate anhydrous (DCPA) mixed with an aqueous NaH(2)PO(4) solution, 1.5 mol/L or 3.0 mol/L in concentration, and (2) tetracalcium phosphate consisting of combinations of particles of two different size distributions, 5 μm (TTCP5) and 17 μm (TTCP17) in median size, mixed with glycerin. Equal volume of Pastes 1 and 2 were injected with the use of atwo-barrel syringe fitted with a static mixer into sample molds. The molar Ca/P ratio of combined paste was approximately 1.5. Cements were characterized in terms of setting time (Gilmore needle), diametral tensile strength (DTS), and phase composition (powder x-ray diffraction, XRD). Setting times were found to range from (4.3 ± 0.6 to 68 ± 3) min (mean ± sd; n = 3), and 1-d and 7-d DTS values were from (0.89 ± 0.08 to 2.44 ± 0.16) MPa (mean ± sd; n = 5). Both the NaH(2)PO(4) concentration and TTCP particle size distribution had significant (p < 0.01) effects on setting time and DTS. Powder XRD analysis showed that low crystallinity HA and unreacted DCPA were present in the 1-day specimens, and the extent of HA formation increased with increasing amount of TTCP5 in the TTCP paste. CONCLUSION: Injectable HA-forming premixed CPCs with setting times from 4 to 70 min can be prepared by using DCPA and TTCP as the ingredients. Compared to the conventional powder liquid cements, these premixed CPCs have the advantages of being easy to use and having a range of hardening times. 相似文献