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91.
Rowley Stephanie J.; Burchinal Margaret R.; Roberts Joanne E.; Zeisel Susan A. 《Canadian Metallurgical Quarterly》2008,44(6):1537
This study examined the effect of changes in racial identity, cross-race friendships, same-race friendships, and classroom racial composition on changes in race-related social cognition from 3rd to 5th grade for 73 African American children. The goal of the study was to determine the extent to which preadolescent racial identity and social context predict expectations of racial discrimination in cross-race social interactions (social expectations). Expectations of racial discrimination were assessed using vignettes of cross-race social situations involving an African American child in a social interaction with European Americans. There were 3 major findings. First, expectations for discrimination declined slightly from 3rd to 5th grade. Second, although racial composition of children's classrooms, number of European American friends, gender, and family poverty status were largely unrelated to social expectations, having more African American friends was associated with expecting more discrimination in cross-racial interactions from 3rd to 5th grade. Third, increases in racial centrality were related to increases in discrimination expectations, and increases in public regard were associated with decreases in discrimination expectations. These data suggest that as early as 3rd grade, children are forming attitudes about their racial group that have implications for their cross-race social interactions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Although some theorists claim that attributions are antecedents of mood changes, others argue that they are consequents. It is difficult to resolve this controversy satisfactorily because (a) the possibility that attributions are causally related to mood but mediated by another variable has not been considered fully, and (b) additional longitudinal research, particularly about how attributions are related to the offset of dysphoria, needs to be completed. We report a concurrent and longitudinal study addressing these issues. The concurrent study replicated and extended previous research, demonstrating that attributions for test performance were correlated with sanctions of affirmation and blame when they were correlated with mood. Furthermore, sanctions were more strongly associated with mood than were attributions. In the longitudinal study, sanctions decreased for subjects reporting decreased dysphoria and remained constant for those reporting stable mood. A similar consistency between the patternings of moods and attributions was not found. These results suggest that attributions are related to mood when their effects are mediated by sanctions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
94.
Sarah A. Brockbank Jenna L. Russon Neil F. Giles Richard L. Rowley W. Vincent Wilding 《International Journal of Thermophysics》2013,34(11):2027-2045
A database containing Henry’s law constants, infinite dilution activity coefficients, and solubility data of industrially important chemicals has been compiled for aqueous systems. These properties are important in predicting the fate and transport of chemicals in the environment. The structure of this database is compatible with the existing $\hbox {DIPPR}^{\circledR }$ 801 database and DIADEM interface, and data are included for a subset of compounds found in the $\hbox {DIPPR}^{\circledR }$ 801 database. Thermodynamic relationships, chemical family trends, and predicted values were carefully considered when designating recommended values. 相似文献
95.
Hypoxic-ischemic changes in brain are detected earlier with diffusion-weighted (DW) than with T2-weighted magnetic resonance (MR) imaging techniques in adults, whereas the response in immature brain is not known. We investigated MR imaging changes prior to, during, and/or after 2 h of hypoxia-ischemia (right carotid artery occlusion + 2 h of hypoxia) in 7-day-old rats anesthetized with isoflurane. In general, within the first 45 min of hypoxia-ischemia there were no changes in the DW or T2-weighted images. By the second hour of hypoxia-ischemia there were marked areas of increased intensity in both the T2 and the DW images, with cortex and striatum being affected prior to thalamus and hippocampus. The area of DW exceeded that of T2 hyperintensities. In the first hour after hypoxia-ischemia there was a transient recovery of hyperintensities on both T2 and DW images. Between 24 and 72 h the hyperintense area on DW images decreased, whereas that on T2-weighted images increased. The distribution of pathological damage assessed histologically correlated with the areas of hyperintensity on the MR images. In contrast to adult brain, early hypoxic-ischemic injury in immature brain is detected as an increase in intensity in both diffusion- and T2-weighted images, indicating a unique alteration in brain water dynamics in this neonatal model of hypoxia-ischemia. These imaging changes and alterations in brain water can rapidly but transiently reverse upon the start of normoxia and reperfusion, suggestive of secondary energy failure or delayed neuronal death. 相似文献
96.
Published flash point prediction methods are evaluated for accuracy against experimental data from the DIPPR ® 801 database. The most accurate methods require a vapor pressure correlation, which is often not available. Two new methods are presented, one that uses the vapor pressure, and one based on the normal boiling point and enthalpy of vaporization at the normal boiling point. The vapor pressure method shows little improvement over the previous methods unless group contributions are implemented. The boiling point method predicts the flash point within an absolute average deviation of 1.3% when compared with data for more than 1000 compounds. The previous most accurate method that was not based on vapor pressure exhibited an absolute average deviation of 1.84% for the same test set. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
97.
A. González C. Rowley E. J. OBrien 《International journal for numerical methods in engineering》2008,75(3):335-354
Bridge weigh‐in‐motion systems measure bridge strain caused by the passing of a truck to estimate static axle weights. For this calculation, they commonly use a static algorithm that takes the bridge influence line as reference. Such a technique relies on adequate filtering to remove bridge dynamics and noise. However, filtering can lead to the loss of a significant component of the underlying signal in bridges where the vibration does not have time to complete sufficient number of cycles and in cases of closely spaced axles traveling at high vehicle speeds. In order to overcome these limitations and also to provide additional information on the dynamics of the applied forces, this paper presents an algorithm based on first‐order Tikhonov regularization and dynamic programming. First, strain measurements are simulated using an elaborate three‐dimensional vehicle and orthotropic bridge interaction system. Then, strain is contaminated with noise and input into the moving force identification algorithm. The procedure to implement the algorithm and to derive the applied forces from the simulated strain record is described. Vehicle axle forces are shown to be accurately predicted for smooth and rough road profiles and a range of speeds. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
98.
Elmer B. Rowley 《Rocks & Minerals》2013,88(9-10):528-532
99.
The neuronal ceroid lipofuscinoses (NCLs) are a group of inherited degenerative neurological diseases affecting children. A number of non-allelic variants have been identified within the human population and the genes for some of these have recently been identified. The underlying mechanism for the neuropathology remains an enigma; however, pioneering studies with the naturally occurring ovine model (OCL) have led to the proposal that these diseases represent lesions in specific hydrophobic protein degradation pathways. In this study, we show linkage between OCL and microsatellite markers on OAR 7q13-15. Using interspecies chromosome painting we establish that OAR 7q13-15 is syntenic with human chromosome 15q21-23, the region which was recently defined as the location of a newly identified late infantile variant (CLN6). We propose that our ovine model represents a mutation in the gene orthologous to that mutated in the human late infantile variant CLN6. The ovine linkage flock, consisting of 56 families, represents a powerful resource for positional cloning of this NCL gene. The availability of such a large animal model will have important implications for experimentation in downstream corrective therapies. 相似文献
100.