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61.
62.
[Correction Notice: An erratum for this article was reported in Vol 44(1) of Developmental Psychology (see record 2007-19851-021). The DOI for the supplemental materials was printed incorrectly. The correct DOI is as follows: http://dx.doi.org/10.1037/0012-1649.43.6.1579.supp.] Some normally developing young children show an intense, passionate interest in a particular category of objects or activities. The present article documents the existence of extremely intense interests that emerge very early in life and establishes some of the basic parameters of the phenomenon. Surveys and interviews with 177 parents revealed that nearly one third of young children have extremely intense interests. The nature of these intense interests is described, with particular focus on their emergence, commonalities in the content of the interests, and the reactions of other people to them. One of the most striking findings is a large gender difference: Extremely intense interests are much more common for young boys than for girls. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
63.
The compatibility of pullulan with maleic acid/vinyl acetate copolymers in the solid state in the form of thin films was studied with thermogravimetry, differential scanning calorimetry, infrared spectroscopy, and optical microscopy. With respect to morphology, blends with a content of pullulan greater than 85 wt % exhibited an even distribution of finely dispersed particles. The thermal properties were dependent on the mixing ratio, and the interactions between components were quite pronounced in the pullulan‐rich blends. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1782–1791, 2002  相似文献   
64.
The serum fatty acid profiles of patients receiving either intravenous medium or long chain triglycerides were studied. Seventeen hospitalized patients, dependent on total parenteral nutrition, were randomly enrolled into a prospective study. The total parenteral nutrition (TPN) delivered amino acids and glucose and either a 75% medium chain triglyceride and 25% long chain triglyceride (MCT group) physical mixture or all long chain triglyceride (LCT group), as the respective fat sources. The amino acids and glucose were given continously, and the lipid was given for 10 hours each day over five days. Fatty acid profiles on serum triglycerides and free fatty acids were done in the morning before any lipid was given and also later in the afternoon, near the end of the lipid administration, on days 1, 3 and 5. Medium chain fatty acids rose quickly in the triglyceride fraction in patients given MCT. Rapid MCT hydrolysis occurred as evidenced by the appearance of medium chain fatty acids in the free fatty acid fraction in the afternoon sampling. Clearance of the hydrolyzed medium chain free fatty acids (MCFFA) occurred so that little, if any, were present in the morning sampling one day later. Long chain fatty acids, as either triglycerides or free fatty acids, showed expected increases during the daily infusion, but not of such relative magnitude as the medium chain fatty acids. Medium chain fatty acid incorporation into the phospholipid or cholesterol ester fractions by the end of the five-day feeding period was present but minimal. As opposed to conventional long chain triglycerides, intravenously administered medium chain triglycerides are hydrolyzed and cleared rapidly and do not accumulate in other lipid fractions, and are therefore a more readily available lipid fuel.  相似文献   
65.
Factor H (FH) contributes to the regulation of the complement system by binding to polyanionic surfaces and the proteins C3b/C3c/C3d. This implicates charge and electrostatic interactions in recognition and binding of FH. Despite the large amount of experimental and pathology data the exact mechanism at molecular level is not yet known. We have implemented a computational framework for comparative analysis of the charge and electrostatic diversity of FH modules and C3b domains to identify electrostatic hotspots and predict potential binding sites. Our electrostatic potential clustering analysis shows that charge distributions and electrostatic potential distributions are more useful in understanding C3b-FH interactions than net charges alone. We present a model of non-specific electrostatic interactions of FH with polyanion-rich surfaces and specific interactions with C3b, using our computational data and existing experimental data. We discuss the electrostatic contributions to the formation of the C3b-FH complex and the competition between FH and Factor Bb (Bb) for binding to C3b. We also discuss the significance of mutations of charged amino acids in the pathobiology of FH-mediated disease, such as age-related macular degeneration, atypical hemolytic uremic syndrome, and dense deposit disease. Our data can be used to guide future experimental studies.  相似文献   
66.
Nanocomposites consisting of hydroxyapatite (HA) and a sodium maleate copolymer (maleic polyelectrolyte), synthesized by hydrothermal method and deposited on titanium substrates by Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique were tested for the biological properties. Coating bioanalysis was carried out by triple staining of actin, microtubules and nuclei followed by immunofluorescence microscopy. Within 24 h cells that occupied the biomaterial surface displayed the morphology and cytoskeleton pattern similar to the controls. Cells grown on nanocomposite coated surfaces had a higher proliferation rate than their counterparts grown on Ti coated with HA alone, indicating that maleic polyelectrolyte improved surface bio-adhesive characteristics. The capacity to induce cell attachment, spreading and proliferation demonstrated the potential of Ti coated with HA-polymer nanocomposites to be used as scaffolds in dental or orthopedic implantology.  相似文献   
67.
Lower limb malalignment is a common cause of disability that increases risk of osteoarthritis (OA). Treatment of OA may require an osteotomy or arthroplasty, which mandate accurate evaluation of mechanical loading on the limbs to achieve optimal alignment and minimal implant wear. Surgical planning uses a conventional method of mechanical axis deviation (MADC) measured from the center of the femoral head to the center of the ankle. This method fails to account for hindfoot deformity distal to the ankle. We used a computer model to compare MADC with the ground mechanical axis deviation (MADG), drawn from the center of the hip to the ground reaction point. Average anatomic measurements were analyzed with a range of knee and hindfoot angle variation in single leg stance, double leg stance, toe off and heel strike. MADG was consistently higher than MADC, suggesting a more complete estimate of weight-bearing axis that considers hindfoot deformity.  相似文献   
68.
Advances in the operationalization of psychopathy have led to an increased understanding of the boundaries, structure, and nomological network of this construct, although significant questions remain. The empirical identification of replicable and theoretically meaningful psychopathy subtypes may help to improve the classification and diagnosis of this condition. We conducted a classification study of 91 incarcerated men who met conventional criteria for high levels of psychopathy using the Psychopathy Checklist-Revised. We expanded on the methodology of previous research on psychopathy subtypes by utilizing a comprehensive personality assessment instrument and a prototype matching approach to classification. The analyses revealed a primary (narcissistic) subtype and a secondary (hostile and dysregulated) subtype that were broadly consistent with the previous literature. External validation analyses, statistical controls, and incremental validity analyses provided substantial support for the primary and secondary subtypes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
69.
Starch retrogradation is a consequential part of food processing that greatly impacts the texture and acceptability of products containing both starch and proteins, but the effect of proteins on starch retrogradation has only recently been explored. With the increased popularity of plant-based proteins in recent years, incorporation of proteins into starch-based products is more commonplace. These formulation changes may have unforeseen effects on ingredient functionality and sensory outcomes of starch-containing products during storage, which makes the investigation of protein–starch interactions and subsequent impact on starch retrogradation and product quality essential. Protein can inhibit or promote starch retrogradation based on its exposed residues. Charged residues promote charge–dipole interactions between starch-bound phosphate and protein, hydrophobic groups restrict amylose release and reassociation, while hydrophilic groups impact water/molecular mobility. Covalent bonds (disulfide linkages) formed between proteins may enhance starch retrogradation, while glycosidic bonds formed between starch and protein during high-temperature processing may limit starch retrogradation. With these protein–starch interactions in mind, products can be formulated with proteins that enhance or delay textural changes in starch-containing products. Future work to understand the impact of starch–protein interactions on retrogradation should focus on integrating the fields of proteomics and carbohydrate chemistry. This interdisciplinary approach should result in better methods to characterize mechanisms of interaction between starch and proteins to optimize their food applications. This review provides useful interpretations of current literature characterizing the mechanistic effect of protein on starch retrogradation.  相似文献   
70.
The binary phase diagram for Cr-doped Zn7Sb2O12 was determined and compared with that for Ni-doped Zn7Sb2O12. The β  α transition temperature, 1225 °C for undoped Zn7Sb2O12, decreases extremely rapidly with increasing Cr content; the solubility limit of Cr in β-Zn7Sb2O12 is <1% but 37.5% in α-Zn7Sb2O12. Bond valence sum calculations for the tetrahedral site, which contains exclusively Zn, show it to be significantly underbonded in undoped α-Zn7Sb2O12, but less underbonded with increased Ni2+ and especially Cr3+ content, thus providing an explanation for the stabilisation of α-Zn7Sb2O12 to lower temperatures on doping with Ni and especially Cr. Sub-solidus compatibility relations in the ternary system ZnO–Sb2O5–Cr2O3 were determined at 1100 °C for compositions containing ≤50% Sb2O5.  相似文献   
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