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排序方式: 共有113条查询结果,搜索用时 15 毫秒
61.
CL Shuler N Allison S Holcomb M Harlan J McNeill G Robinett SP Bagby 《Canadian Metallurgical Quarterly》1998,158(7):714-721
OBJECTIVES: The review lists the child psychiatry day-care centres in Quebec, evaluates their capacity, and describes them according to the age range for admission, the psychopathologies treated, and the parent involvement required. METHOD: The 26 programs selected, which are all associated with a hospital centre, assess and treat children aged 0 to 12 years on a day-care basis. Organization, clinical operation, and research are addressed during a semisupervised interview. RESULTS: The average capacity is 18 children (4 to 40), with a total capacity of 454 children. The number of preschool patients can be compared with the number of school patients. Few programs are dedicated to invasive development disorders, and one-third treat behavioural or emotional disorders. The larger capacity programs treat patients of both genders. Most programs are eclectic and encourage but do not require parental involvement. CONCLUSIONS: Results take into account different theoretical influences, the controversy about integration criteria and parent involvement, and the specificity of the child psychiatry mission. 相似文献
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64.
Harlan J. Brown-Shaklee 《Solar Energy Materials & Solar Cells》2009,93(8):1404-1410
Composite porcelain-enamel coatings consisting of spinel-type transition-metal-oxide pigments embedded in a borosilicate-glass matrix were deposited on 321 stainless steel using screen-printing techniques and characterized using total reflectance over the spectral range of 200 nm to 25 μm. The composite coatings exhibited moderate spectral selectivity and excellent thermal stability at 450 °C. Solar absorptance (α) ranged from 0.82 to 0.90 and calculated thermal emittance at 500 °C (ε) ranged from 0.46 to 0.79. Both depended on coating thickness and pigment volume concentrations. As an example, the highest solar selectivity was measured in a 0.9 μm coating with α and ε (500 °C) being 0.82 and 0.46, respectively. 相似文献
65.
The tamarillo (tree tomato, Cyphomandra betacea Sendt.) flowers and sets fruit over an extended period. Many blossoms and young fruits abscise; survival of tagged fruitlets ranged from 0 to 32%. Tagged fruits were harvested at known ages for measurement of size and shape, respiration rate, ethylene production, and response to ethylene treatment. Fruit growth followed a single sigmoid pattern, and fruits were commercially mature at 21–24 weeks after anthesis. The amount of red skin pigment increased with age from 15 weeks, but harvesting of immature fruits appeared to stop red pigment development. Fruits harvested at 12–19 weeks or younger shrivelled in storage. Respiration studies showed tamarillo fruits to be non-climacteric, and only traces of ethylene were produced until final senescence. Ethylene treatment increased the respiration rate and hastened senescence of harvested fruits of all ages. The yellow strain behaved similarly to the red and had a somewhat longer storage life. 相似文献
66.
Fruits of Chinese gooseberry (Actinidia chinensis Planchon, cv. Bruno) were harvested and respiration rates and other attributes were measured at regular intervals throughout the season. The fruit matured at about 23 weeks after anthesis as shown by patterns of respiration, response to ethylene treatment and changes in texture and content of soluble solids. Fruit growth followed a unique triple sigmoid curve. Natural ripening showed the fruits to be of climacteric type but, although associated with a peak of ethylene production, the respiratory pattern was somewhat atypical and initiation of ripening within any lot of uniform fruits was very variable. Ethylene treatment stimulated ripening in fruits of all ages, but a large induced respiratory peak was seen only in immature fruits. The physiological observations confirmed present horticultural practices and provide a basis for development of objective enforceable quality grades. 相似文献
67.
Analysis of integrin (CD11b/CD18) movement during neutrophil adhesion and migration on endothelial cells 总被引:1,自引:0,他引:1
Little is known of the distribution of cell surface molecules during the adhesion and migration of leucocytes on endothelial cells. We have used confocal microscopy and a Fab fragment of a non-inhibitory monoclonal antibody recognizing the integrin CD11b/CD18 (Mac-1) to study the movement of this adhesion molecule over time. We found that during the initial stage of neutrophil contact with TNF-α activated human umbilical vein endothelial cells (HUVEC), there is a rapid accumulation of Mac-1 at the contact area between the two cell types. As the neutrophil spreads, Mac-1 redistributes away from this initial contact area. During neutrophil migration on HUVEC, Mac-1 was redistributed to the leading edge of the migrating cell, suggesting that the existing cell surface pool of adhesion molecules is dynamic and can be recruited to the leading front as the cell changes direction. As neutrophils migrate on HUVEC, Mac-1-dense macroaggregates are rapidly formed and broken down at the contact plane between the two cells. The confocal microscope, coupled with the use of non-inhibitory antibodies labelled with photostable fluorophores, is a useful tool for the study of the movement of cell surface molecules over time. 相似文献
68.
A model for the electrical conductivity in acceptor-doped oxides which involves an association between the acceptor-dopants and oxygen vacancies resulting in donor centers is considered. The model relates the behavior of the electrical conductivity with the temperature, ambient atmosphere and band structure. The predictions of the model are compared to experimental data for ZrO2:16% Y and SrCeO3:5% Yb oxygen conductors and some band structure parameters have been determined. 相似文献
69.
Electrical Conductivity and Lattice Defects in Nanocrystalline Cerium Oxide Thin Films 总被引:2,自引:0,他引:2
Toshio Suzuki Igor Kosacki Harlan U. Anderson Philippe Colomban 《Journal of the American Ceramic Society》2001,84(9):2007-2014
The results of the electrical conductivity and Raman scattering measurements of CeO2 thin films obtained by a polymeric precursor spin-coating technique are presented. The electrical conductivity has been studied as a function of temperature and oxygen activity and correlated with the grain size. When compared with microcrystalline samples, nanocrystalline materials show enhanced electronic conductivity. The transition from extrinsic to intrinsic type of conductivity has been observed as the grain size decreases to <100 nm, which appears to be related to a decrease in the enthalpy of oxygen vacancy formation in CeO2 . Raman spectroscopy has been used to analyze the crystalline quality as a function of grain size. A direct comparison has been made between the defect concentration calculated from coherence length and nonstoichiometry determined from electrical measurements. 相似文献
70.
To better understand the role of the substrate in the microstructural evolution of thin films, unsupported nanocrystalline yttrium-stabilized zirconia (ZrO2 :16%Y or YSZ) films were examined as a function of temperature and annealing time. Grain growth, texturing, and pinhole formation were measured using transmission electron microscopy (TEM) and electron diffraction. Films were produced and subsequently annealed on metallic grids using a previously developed technique that results in near full density films at low annealing temperatures. Microstructural evolution in these films was unique compared with constrained films. Grains were found to spheroidize much more readily, ultimately resulting in the formation of porosity and pinholes. Grain growth was found to stagnate at a size particular to each annealing temperature, presumably due to the effects of Zener pinning. It is proposed that the lack of substrate strain and confinement effects allows for the dominance of surface energetics with respect to microstructural evolution. 相似文献