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951.
The Minnesota Criminal Gang Pointer File database and GangNet database were established by law enforcement agencies as tools to monitor alleged gang members and reduce criminal gang activity. Law enforcement agencies have traditionally used gang databases to ensure public safety in the communities they serve. St Paul community members have raised concerns regarding the use of gang databases and the impact this has had, and continues to have, on those who have been mislabeled as gang members or are no longer part of a gang. In response to these community concerns, this report was compiled to highlight the various issues with the implementation, documentation, and use of Minnesota Criminal Gang Pointer File and GangNet databases, and offer recommendations for change.  相似文献   
952.
In recent years, there has been growing interest in the influence of sprouts on health. Fruit and vegetables are the main sources of organic acids for humans; however, little is yet known about organic acids in sprouts. In this study, the selection of the optimal parameters for extraction of organic acids from fresh, edible sprouts is reported. Two extraction techniques: microwave-assisted (MAE) and ultrasound-assisted were compared. The experimental conditions were optimized in terms of extraction time, temperature, and composition of extraction solution. To determine the influence of time and temperature of extraction or sample cooling, solvents used for extraction, on the analytical signal in isotachophoretic separation, the methods of experimental planning fractional factorial design: 3k?1 were used (three factor, three-level design). The optimal conditions for extraction of organic acids from radish sprouts were MAE, 90 °C; 18 min; and 0.01 M NaOH as a solvent.  相似文献   
953.
In this study, major types of flavonoids in 7‐day sprouts of five common buckwheat cultivars grown in Poland (Hruszowska, Kora, Panda, Luba and Emka) and wild tartary buckwheat were investigated. Results demonstrated that sprouts of common buckwheat cultivars and wild tartary buckwheat contained both known and a newly discovered flavonol: quercetin 3‐O‐galactosyl‐rhamnoside. An exceptionally high content of this flavonoid was found in cotyledons of wild tartary buckwheat (30.79 ± 0.14 mg g?1 DW), exceeding about 10 times level of rutin (3.16 ± 0.07 mg g?1 DW). The results are not consistent with the data published so far on the content of flavonoids in sprouts of tartary buckwheat. Higher levels of flavonoids were measured in cotyledons than in hypocotyls with the exception of anthocyanins, which were present in higher amounts in hypocotyls. Cotyledons of common buckwheat sprouts were rich in C‐glycosides of luteolin and apigenin, the total content of which exceeded ca. 5 times the concentration of rutin.  相似文献   
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956.
At the CHEP03 conference, we launched the Physics Analysis eXpert (PAX), a C++ toolkit released for the use in advanced high energy physics (HEP) analyses. This toolkit allows to define a level of abstraction beyond detector reconstruction by providing a general, persistent container model for HEP events. Physics objects such as particles, vertices and collisions can easily be stored, accessed and manipulated. Bookkeeping of relations between these objects (like decay trees, vertex and collision separation, etc.) including deep copies is fully provided by the relation management. Event container and associated objects represent a uniform interface for algorithms and facilitate the parallel development and evaluation of different physics interpretations of individual events. So-called analysis factories, which actively identify and distinguish different physics processes and study systematic uncertainties, can easily be realized with the PAX toolkit. PAX is officially released to experiments at Tevatron and LHC. Being explored by a growing user community, it is applied in a number of complex physics analyses, two of which are presented here. We report the successful application in studies of tt~ production at the Tevatron and Higgs searches in the channel tt~H at the LHC and give a short outlook on further developments.  相似文献   
957.
Electron transfer reactions in proteins and peptides are crucial for biological energy conversion. Therefore, an important goal of fundamental research is to provide scientific insight into the mechanisms determining the bridge-mediated electron transport. One of the main tasks is to understand how the efficiency of this process is affected by the particular structure of a peptide, as well as the surrounding environment, and eventually, how we can control it by means of external chemical and physical factors. The latter could be of crucial importance for the design and development of biosensors and other functional devices, which may benefit from the unique electron transfer properties of peptides. Monolayers immobilized on solid surfaces seem to be particularly useful for that purpose. In this paper, we present the progress of fundamental research related to electron transport through peptides adsorbed onto metal surfaces. Specifically, we have focused on electrochemical studies and nanoscale molecular junction approaches. We have critically reviewed existing data and discussed the discrepancies in the measured efficiencies of electron transport. Some suggestions for future fundamental research in this area are provided. In particular, the need to combine the electrochemical and molecular junction approaches to explore the conductance behavior of peptides under full electrochemical control is emphasized. Some potential applications of peptide monolayers, which take advantage of the unique electrical properties of these compounds, are also discussed.  相似文献   
958.
Biological materials are typically multifunctional but many have evolved to optimize a chief mechanical function. These functions include impact or fracture resistance, armor and protection, sharp and cutting components, light weight for flight, or special nanomechanical/chemical extremities for reversible adhesive purposes. We illustrate these principles through examples from our own research as well as selected literature sources. We conduct this analysis connecting the structure (nano, micro, meso, and macro) to the mechanical properties important for a specific function. In particular, we address how biological systems respond and adapt to external mechanical stimuli. Biological materials can essentially be divided into mineralized and non-mineralized. In mineralized biological materials, the ceramics impart compressive strength, sharpness (cutting edges), and stiffness while the organic components impart tensile strength, toughness and ductility. Non-mineralized biological materials in general have higher tensile than compressive strength, since they are fibrous. Thus, the mineralized components operate optimally in compression and the organic components in tension. There is a trade-off between strength and toughness and the stiffness and density, with optimization. Mineralization provides load bearing capability (strength and stiffness) whereas the biopolymer constituents provide viscoelastic damping and toughness. The most important component of the nascent field of Biological Materials Science is the development of bioinspired materials and structures and understanding of the structure–property relationships across various length scales, from the macro-down to the molecular level. The most successful efforts at developing bioinspired materials that attempt to duplicate some of the outstanding properties are presented.  相似文献   
959.
Objective: Clear evidence suggests that lifestyle interventions can be helpful in the treatment of youth who are overweight, but translational research is needed to address the gap between treatment research and clinical care. Design: This meta-analysis integrated the results of 66 treatment–control comparisons and 59 alternate treatment comparisons evaluating lifestyle interventions for children and adolescents who were overweight. Main Outcome Measures: Between-groups differences in weight-related outcomes and other health-related behaviors at the end of treatment. Results: Lifestyle interventions were effective in a range of settings and with a range of participants. Even relatively brief programs had benefits apparent months after the end of treatment. A key component appeared to be the expectation that parents would be actively involved in treatment. Program benefits included not only better weight management but also better eating habits. Conclusion: The results suggest that lifestyle interventions can be effective under a wide range of conditions not limited to the highly controlled conditions of efficacy studies. Parent involvement is associated with significantly better results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
960.
Development of Microporosity in Mesoporous Carbons   总被引:1,自引:0,他引:1  
Monolithic carbons with uniform and spherical mesopores can be easily obtained by filling the pores of colloidal silica monoliths with carbon precursors followed by carbonization and silica dissolution. In this study three different phenolic resin blends: resorcinol and crotonaldehyde (MC-RC), phenol and paraformaldehyde (MC-PP), and resorcinol and furfural (MC-RF) were used as carbon precursors. Subsequent heating and carbonization of the resulting silica–phenolic resin nanocomposites followed by silica dissolution afforded monolithic carbons with spherical mesopores matching the size of the silica colloids used. Development of microporosity in these carbons was achieved by post-synthesis KOH activation. This study shows that the combination of colloidal templating with post-synthesis activation affords monolithic micro–mesoporous carbons with large specific surface area and well-developed accessible porosity for adsorption, catalysis, environmental and energy-related applications.  相似文献   
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