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971.
Since the nutritional value of farm‐raised fish fillets is directly related to the diet provided, we supplemented the diet of Tilapia (Oreochromis niloticus) with a blend of chia (Salvia hispanica L.) oil, tung (Aleurites fordii) oil, and conjugated linoleic acid (CLA) to evaluate the effects on the fatty acid composition. Vitamin E was also added to the diet to improve the antioxidant capacity of tilapia fillets. We observed an increase in α‐linolenic acid content (from 6.56 to 19.03 mg g?1 of total lipids), as well as the incorporation of CLA and conjugated linolenic acid (CLnA) isomers in the fillets. The addition of vitamin E resulted in the antioxidant capacity improvement of the fillets and higher values were found after 15 feeding days (39.25 µmol TE g?1 in the Ferric Reducing Ability Power assay). Supplementation proved to be an excellent tool to improve the nutritional value of fish fillets.  相似文献   
972.
973.
Two types of cationic cyclic α,α‐disubstituted α‐amino acids: Api (which possesses a lysine mimic side chain) and ApiC2Gu (which possesses an arginine mimic side chain), were developed. These amino acids were incorporated into an arginine‐based peptide sequence [(l ‐Arg‐l ‐Arg‐dAA)3: dAA=Api or ApiC2Gu], and the relationship between the secondary structures of the resulting peptides and their ability to pass through cell membranes was investigated. The peptide containing ApiC2Gu formed a stable α‐helical structure and was more effective at penetrating cells than the nonhelical Arg nonapeptide (R9). Furthermore, the peptide was able to deliver plasmid DNA into various types of cells in a highly efficient manner.  相似文献   
974.
Liver X receptor (LXR) agonists are candidates for the treatment of atherosclerosis via induction of ABCA1 (ATP‐binding cassette A1) gene expression, which contributes to reverse cholesterol transport (RCT) and to cholesterol efflux from the liver and intestine. However, LXR agonists also induce genes involved in lipogenesis, such as SREBP‐1c (sterol regulatory binding element protein 1c) and FAS (fatty acid synthase), thereby causing an undesirable increase in plasma and hepatic triglyceride (TG) levels. Recent studies indicate that LXRα contributes to lipogenesis in liver, and selective LXRβ activation improves RCT in mice. Therefore, LXRβ‐selective agonists are promising candidates to improve atherosclerosis without increasing plasma or hepatic TG levels. However, the ligand‐binding domains in the two LXR isoforms α/β share high sequence identity, and few LXR ligands show subtype selectivity. In this study we identified a tetrachlorophthalimide analogue as an LXRβ‐selective agonist. Structural development led to (E)‐4,5,6,7‐tetrachloro‐2‐(2‐styrylphenyl)isoindoline‐1,3‐dione ( 24 a ), which shows potent and selective LXRβ agonistic activity in reporter gene assays. In binding assays, compound 24 a bound to LXRβ preferentially over LXRα. It also induced the expression of ABCA1 mRNA but not SREBP‐1c mRNA in cells. Compound 24 a appears to be a promising lead compound for therapeutic agents to treat atherosclerosis without the side effects induced by LXRα/β dual agonists.  相似文献   
975.
Magnetic resonance imaging provides important intravital information on deep tissues that cannot be visualized by other methods. Although we had previously developed an off/on switching (19)F MRI probe to monitor reporter enzyme activity on the basis of the paramagnetic relaxation enhancement effect, it was difficult to monitor biological events in living cells because the (19)F MRI probe did not permeate living cell membrane. In this study, we have developed a new (19)F MRI system for monitoring gene expression in living cells by exploiting cell-surface-displayed β-lactamase and the specifically designed (19)F MRI probe. By using this system, cellular gene expression was successfully detected by (19)F MRI without cell fixation. This imaging strategy shows promise for monitoring in vivo gene expression, and therefore it could lead to useful technologies for the diagnosis and therapy of various diseases.  相似文献   
976.
The authors study plasmonic enhancements of photoluminescence (PL) in Si nanodisk (ND) arrays hybridized with nanostructures such as nanoplates of Au, where these hybrid nanostructures are fabricated by fully top-down lithography: neutral-beam etching using bio-nano-templates and high-resolution electron-beam lithography. The separation distance between the Si ND and Au nanostructure surfaces is precisely controlled by inserting a thin SiO2 layer with a thickness of 3 nm. We observe that PL intensities in the Si NDs are enhanced by factors up to 5 depending on the wavelength by integrating with the Au nanoplates. These enhancements also depend on the size and shape of the Au nanoplates.  相似文献   
977.
The sleep-promoting effect of isoliquiritigenin (ILTG) was investigated by analyzing the sleep architecture in mice. A hypnotic diazepam (DZP, 2 mg/kg) significantly decreased sleep latency by 39.7% and increased the amount of non-rapid eye movement sleep (NREMS) by 103.8% for the first 3 h after administration. ILTG (50 mg/kg) also produced a significant decrease in sleep latency (30.7%) and an increase in the amount of NREMS (61.1%). DZP significantly decreased delta (0.5–4 Hz) activity as compared with the vehicle; however, ILTG did not alter the delta activity. These results mean that ILTG induces sleep similar to physiological sleep without a decline in sleep quality.  相似文献   
978.
ABSTRACT

Ammonium nitrate (AN) propellants have attracted attention because of their low cost and ecofriendliness despite certain major disadvantages such as low burning rate, poor ignitability, low energy, and volume change due to phase transition of AN. The addition of nitramine to AN propellants is one of the approaches to overcome these disadvantages. However, AN/nitramine propellants are characterized by easy initiation, high sensitivity, and high detonation velocity because of the high energy of nitramine. The detonation properties of AN/nitramine propellants were investigated in this study. It was observed that the AN/nitramine propellant required a booster to detonate the propellants, as detonation did not occur while using only a commercial electric blasting cap. It was further observed that the detonation velocity (D) increased linearly as the mass of nitramine per unit propellant volume was increased, and AN had a negligible effect on the detonation properties. An approximate equation was derived from the relationship between D and the mass per unit propellant volume of nitramine. The dominant factors that can be used to estimate the detonation/no-detonation boundaries of the propellants were identified, and the experimental boundary equations were determined using these factors.  相似文献   
979.
A method to recognize speed limit signs in night scene images is proposed in this paper. The proposed method involves two main stages. First, sign candidates are detected by using the outline of white domain on the signs. This region has little influence on the change of color information or size. Next, the feature and common parts in speed limit signs are distinguished on the basis of their layout. We extract a suitable label from sign candidates and recognize it as a sign through a matching experiment. Experimental results for 596 images show that the proposed method is able to recognize speed limit signs with an accuracy of 94.3%. It is also shown that 423 images without speed limit signs are perfectly distinguished as images having no speed limit signs. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
980.
Ammonium nitrate (AN)‐based composite propellants have several major problems, namely, a low burning rate, poor ignitability, low energy, and high hygroscopicity. The addition of a burning catalyst proved to be effective in improving the burning characteristics of AN‐based propellants. In this study, the burning characteristics of AN‐based propellants supplemented with MnO2 as a burning catalyst were investigated. The addition of MnO2 is known to improve the ignitability at low pressure. The most effective amount of MnO2 added (ξ) for increasing the burning rate is found to be 4 %. The increasing ratio with ξ is virtually independent of the burning pressure and the AN content. However, the pressure exponent unfortunately increased by addition of MnO2. The apparent activation energy of the thermal decomposition for AN and the propellant is decreased by addition of MnO2. From thermal decomposition kinetics it was found that MnO2 could accelerate the thermal decomposition reaction of AN in the condensed phase, and therefore, the burning characteristics of the AN‐based propellant are improved.  相似文献   
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