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91.
What kind of leg trajectories are selected during human walking? To address this question, we have analyzed leg trajectories from two points of view: constraint and exploitation of redundant degrees of freedom. First, we computed the optimal leg swing trajectories for forward and backward walking that minimize energy cost for the condition of having some stretch of elastic components at the beginning of the leg swing and found that the optimal trajectories explain the characteristics of measured trajectories. Second, we analyzed how and when leg joints cooperate to adjust the toe position relative to the hip position during walking and found that joint coordination (i.e., joint synergy) is exploited at some control points during human walking, e.g., the toe height when it passes through its lowest position from the ground and the leg posture at the beginning of the double-support phase. These results suggest that the basic constraint in selecting a leg trajectory would be the minimization of energy cost; however, the joint trajectory is not strictly controlled over the entire trajectory and redundant degrees of freedom are exploited to adjust the foot position at some critical points that stabilizing walking.  相似文献   
92.
Recent progress in hardware and operating system technologies has made it possible to manage multimedia data consisting of text, static images, sound and/or video. Video data is considered to be the most informative of these types of data. It presents a scene consisting of objects and the motion of objects conveying particular meaning of the scene. Thus, the inherent feature of video data lies in the motion of objects. In this paper, we present a system that retrieves video data by means of the motion of objects observed in the video data in the database. The system accepts a query for a video database, which is specified by drawing an example trajectory of an object, and retrieves video data by extracting a moving object observed in the video data. The proposed way of specifying a query condition is superior to other ways of representing a condition, e.g. by text, in the sense that it is suitable for representing the difference of motion.  相似文献   
93.
In future biorefineries, the development of cheap and environmentally friendly solvents for biomass pretreatment is highly desirable. In this sense, low-transition-temperature mixtures (LTTMs) have high potential to serve as green solvents for replacing conventional pretreatment technologies. In this study, a life cycle assessment of LTTMs pretreatment was conducted to determine the environmental impacts caused by biomass delignification. A gate-to-gate analysis which started with harvested oil palm empty fruit bunch and ended with lignin was selected. The environmental impacts such as acidification potential, global warming potential, eutrophication potential, photochemical ozone creation potential, human toxicity potential and volatile organic compounds emission were evaluated. The comparable environmental balances of commercial l-malic acid and cactus malic acid-based LTTMs pretreatment processes verified the suitability of the process with natural malic acid as the source of proton donor. This study concludes that biomass delignification using natural cactus malic acid-based LTTMs had promising features such as high delignification efficiency and environmentally friendly compared to commercial l-malic acid-based LTTMs. Based on environmental point of view, the overall process of biomass delignification using sucrose-based LTTMs had lower CO2 emissions compared to the monosodium glutamate- and choline chloride-based LTTMs. These findings are important for verifying the greenness and sustainability of LTTMs to be applied at industrial scale.  相似文献   
94.
Modification of organic polymer with silanol groups in combination with calcium salts enables the polymer to show bioactivity, that is, the polymer forms apatite on its surface after exposure to body environment. However, how modification with silanol groups influences ability of apatite formation on the polymer substrate and adhesive strength between polymer and apatite is not yet known. In the present study, polyamide containing carboxyl groups was modified with different amounts of silanol groups, and its apatite-forming ability in 1.5SBF, which contained ion concentrations 1.5 times those of simulated body fluid (SBF), was examined. The rate of apatite formation increased with increasing content of silanol groups in the polyamide films. This may be attributed to enhancement of dipole interactions. A tendency for the adhesive strength of the apatite layer on the polyamide film to be decreased with increasing content of silanol groups was observed. This may be attributed to swelling in 1.5SBF and having a high degree of shrinkage after drying. These findings clearly show that modification of organic polymers with the functional groups induces apatite deposition, and also determines the adhesive strength of the apatite layer to the organic substrates.  相似文献   
95.
Fluctuating market price of fossil fuel and overwhelming emission of greenhouse gases to the atmosphere have resulted in climate change and have been a global concern in this decade.Hence,biodiesel has become an alternative option to fossil diesel as it is renewable and environmentally friendly.Nevertheless,this alternative fuel that is usually derived from terrestrial oil crops will cause shortage in food supply and deforestation if mass production is realized.In recent years,cultivation of aquatic microorganism (particularly microalgae) to produce biodiesel is considered as a practical solution due to their high growth rate and ability to synthesize large quantity of lipid within their cell.However,the development of energy and cost-efficiency of microalgae cultivation system are the main issues in producing renewable microalgae biodiesel.Of late,wastewater or organic compost has been used as the cultivation medium as it can provide sufficient nutrients to sustain microalgae growth.Microalgae cultivation method and system are vitally important as these factors undoubtedly affect the final microalgae biomass and lipid yield.In this review,the cultivation system of microalgae,nutrients demanded for microalgae production,cell harvesting and drying,microalgae oil extraction,and utilization of microalgae biomass for biodiesel production are introduced and discussed.It is anticipated to convey clearer perspectives in upstream and downstream processes in microalgae-derived biodiesel production.  相似文献   
96.
Vibrio parahaemolyticus has been one of the most important foodborne pathogens in Japan since the 1960s, and a large epidemic was caused by the pandemic serotype O3:K6 from 1997 to 2001. V. parahaemolyticus infections, however, have sharply declined since that time. Data on serotypes isolated from 977 outbreaks were collected and analysed. Total and pathogenic, thermostable direct hemolysin (TDH) gene-positive V. parahaemolyticus were qualitatively and quantitatively detected in 842 seafood samples from wholesale markets in 2007-2009. Strains isolated from patients and seafood were analysed by serotyping, tdh-PCR, group-specific PCR for pandemic strains, and pulsed-field gel electrophoresis (PFGE). The sharp decrease in the infections from 1999 onwards was noted not only for O3:K6 infections but also for other serotypes. The change in the seafood contamination situation from 2001 to 2007-2009 was characterised by a decrease to three-fourths in the frequency of tdh-positive samples, although that decrease was small compared to the 18-fold decrease in the cases of V. parahaemolyticus outbreaks. PFGE detected the pandemic O3:K6 serotype in the same profile in seafood and patients from 1998 to the present. Because of no large decrease in seafood contamination by V. parahaemolyticus from the production to distribution stages and the presence of pandemic O3:K6 serotype in seafood to the present, it was suggested that the change of seafood contamination was unrelated to the sharp decrease in V. parahaemolyticus infections. V. parahaemolyticus infections might be prevented at the stages after the distribution stage.  相似文献   
97.
We synthesized a ferroelectric liquid crystal monomer possessing both carboxyl p-benzolxy-benzoate and carboxyl (s)-(-)-2-methylbutyl ester in its side chain. The liquid crystal and styrene monomers were utilized to form matrices of microspheres prepared by the dispersion or suspension polymerization. In this study, we characterized in detail physicochemical properties, thermo-responses, or electro-optical responses in the microspheres. We demonstrated the following results: (1) the volume-averaged diameters of microspheres prepared by the dispersion or suspension polymerization were of 1.5 or 45 μm, respectively, (2) the microspheres prepared showed liquid crystal abilities at the prescribed temperature, (3) the phase transition temperatures toward the liquid crystal phase of the microspheres prepared by copolymerizing the liquid crystal and styrene monomers could be decreased with increasing styrene monomer concentrations, and (4) the microspheres obtained remarkably exhibited electro-optical responses at the appointed voltage.  相似文献   
98.
Although the rate of preterm birth has increased in recent decades, a number of preterm infants have escaped death due to improvements in perinatal and neonatal care. Antenatal glucocorticoid (GC) therapy has significantly contributed to progression in lung maturation; however, its potential effects on other organs remain controversial. Furthermore, the effects of antenatal GC therapy on the fetal heart show both pros and cons. Translational research in animal models indicates that constant fetal exposure to antenatal GC administration is sufficient for lung maturation. We have established a premature fetal rat model to investigate immature cardiopulmonary functions in the lungs and heart, including the effects of antenatal GC administration. In this review, we explain the mechanisms of antenatal GC actions on the heart in the fetus compared to those in the neonate. Antenatal GCs may contribute to premature heart maturation by accelerating cardiomyocyte proliferation, angiogenesis, energy production, and sarcoplasmic reticulum function. Additionally, this review specifically focuses on fetal heart growth with antenatal GC administration in experimental animal models. Moreover, knowledge regarding antenatal GC administration in experimental animal models can be coupled with that from developmental biology, with the potential for the generation of functional cells and tissues that could be used for regenerative medical purposes in the future.  相似文献   
99.
A chronic feeding study to evaluate the safety of the genetically modified glyphosate-tolerant soybeans (GM soybeans) was conducted using rats. F344 DuCrj rats were fed diet containing GM soybeans or Non-GM soybeans at the concentration of 30% in basal diet. Non-GM soybeans were closely related strain of GM soybeans. These two diets were adjusted to an identical nutrient level. In this study, the influence of GM soybeans on rats was compared with that of the Non-GM soybeans, and furthermore, to assess the effect of soybeans themselves, the groups of rats fed GM and Non-GM soybeans were compared with a group fed commercial diet (CE-2). General conditions were observed daily and body weight and food consumption were recorded. At the intermediate examination (26 weeks), and at the termination (52 weeks), animals were subjected to hematology, serum biochemistry, and pathological examination. There were several differences in animal growth, food intake, serum biochemical parameters and histological findings between the rats fed the GM and/or Non-GM soybeans and the rats fed CE-2. However, body weight and food intake were similar for the rats fed the GM and Non-GM soybeans. Gross necropsy findings, hematological and serum biochemical parameters, organ weights, and pathological findings showed no meaningful difference between rats fed the GM and Non-GM soybeans. These results indicate that long-term intake of GM soybeans at the level of 30% in diet has no apparent adverse effect in rats.  相似文献   
100.
Oxidation of low-density lipoprotein (LDL) has been implicated in atherogenesis. Antioxidants that prevent LDL from oxidation may reduce atherosclerosis. We investigated LDL antioxidant activity and extracted compounds of mulberry (Morus alba L.) leaves. The LDL antioxidant activity of 60% ethanol extracted of mulberry leaves, which inhibits human LDL oxidation induced by copper ion, was determined on the basis of oxidation lag time and calculated as epigallocatechin 3-gallate equivalents (58.3 μmol of EGCG equivalent/g of dry weight). Three flavonol glycosides [quercetin 3-(6-malonylglucoside), rutin (quercetin 3-rutinoside) and isoquercitrin (quercetin 3-glucoside)] were identified as the major LDL antioxidant compounds by LC-MS and NMR. The amounts of these flavonol glycosides in mulberry leaves and mulberry-leaf tea were determined by HPLC. Our results showed that quercetin 3-(6-malonylglucoside) and rutin were the predominant flavonol glycosides in the mulberry leaves.  相似文献   
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