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1.
Children's perceived attachments with parents, and family cohesion and adaptability were examined as predictors, mediators, and moderators in the parental problem drinking-child outcomes link. A total of 216 6- to 12-year-olds (110 boys, 106 girls) participated. Data were obtained from children and their mothers, fathers, and teachers. A higher level of family cohesion and adaptability functioned as (a) a robust protective factor against adjustment and cognitive difficulties otherwise associated with problem drinking and (b) a mediator of adjustment problems. Children's perceptions of attachments to mothers and fathers were consistent predictors of behavioral, social, and cognitive problems and further moderated relations between problem drinking and child functioning. The results support that child-parent and family functioning variables act as either pathways and/or vulnerability and protective factors for children exposed to a high-risk environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
Solvent extraction of uranium ions with 4-methylpentan-2-one was examined. The diluent, extractant concentration, aqueous to organic phase ratio, and contact time were varied. Different stripping agents were examined to reach the optimum stripping conditions. The results obtained show that uranium can be quantitatively extracted from 5 M nitric acid with 7% 4-methylpentan-2-one dissolved in refined kerosene and stripped from the organic phase with 5% Na2CO3. The equilibrium is attained within 10 min. Uranium can be efficiently separated from a large number of elements by adding EDTA salt to the stripping solution before uranium precipitation.  相似文献   
3.
Structural engineering analysis tools have been used to improve the understanding of the biomechanical behaviour of the cornea. The research is a multi-disciplinary collaboration between structural engineers, mathematical and numerical analysts, ophthalmologists and clinicians. Mathematical shell analysis and nonlinear finite-element modelling have been used in conjunction with laboratory experiments to study the behaviour of the cornea under different loading states and to provide improved predictions of the mechanical response to disease and injury. The initial study involved laboratory tests and mathematical back analysis to determine the corneal material properties and topography. These data were then used to facilitate the construction of accurate finite-element models that are able to reliably trace the performance of cornea upon exposure to disease, injury or elevated intra-ocular pressure. The models are being adapted to study the response to keratoconus (a disease causing loss of corneal tissue) and to tonometry procedures, which are used to measure the intra-ocular pressure. This paper introduces these efforts as examples of the application of structural engineering analysis tools and shows their potential in the field of corneal biomechanics.  相似文献   
4.
In this research, Ni-W-P-SiC nanocomposite coatings are electrodeposited from the plating solution containing suspension of nano-sized spherical- and rod-shaped SiC particles. The influence of SiC particle charge, applied current density, surfactant addition and the particle shape on the SiC incorporation rate has been studied. The phase structure, microhardness and wear resistance of Ni-W-P-SiC nanocomposite coatings were evaluated using X-ray diffraction (XRD), microhardness tester and wear test apparatus. The surface morphology of the produced coatings and worn surfaces has been investigated using scanning electron microscope (SEM). Additionally, the composite coating exhibited higher hardness and wear resistance than the pure Ni-W-P alloy. Regardless the particle shape, the mechanical characteristics of composite coatings are improved with increasing of SiC wt.% into the matrix. The corrosion behavior of the produced coatings was studied using anodic polarization measurements. The nanocomposite coating incorporating SiC rods exhibited higher mechanical and corrosion performance compared with deposits with spherical SiC nano-particles.  相似文献   
5.
The enhancement of heat transfer from a discrete heat source in confined air jet impingement was experimentally investigated. A variety of pin-fin heat sinks were mounted on the heat source and the resulting enhancement studied, Average heat transfer coefficients are presented for a range of jet Reynolds numbers (8000⩽Re⩽45000) and orifice diameters (12.7⩽d⩽38.1 mm). A total fin effectiveness was computed for the pinned heat sinks relative to the unpinned ones, and was in the range of 2.4 to 9.2; the highest value was obtained for the largest nozzle diameter. Heat transfer rates from the bare heat source were increased by a factor of 7.5 to 72 due to the introduction of the heat sinks. Results for the average heat transfer coefficient were correlated in terms of Reynolds number, fluid properties and geometric parameters of the heat sinks  相似文献   
6.
7.
Several techniques can be used to improve surface properties of metals. These can involve changes on the surface chemical composition such as alloying or on the surface microstructure, such as hardening. In the present work, melting of the surface by a 9 kW CO2 CW laser of wavelength 10.6 μm was used to alter surface features of D2 tool steel. Carbon powder and nitrogen gas were used as sources of alloying elements during laser processing. The effect of various laser parameters (power and speed) on the microstructure and hardness of D2 tool steel was investigated. Laser powers from 1 to 8 kW and laser speeds from 5 to 15 mm/s were employed. It was found that as the laser power increases, the hardness of the melted zone decreases while that of the heat-affected zone increases. On the other hand, the depth of both of melted and heat-affected zones increases with power.  相似文献   
8.
In a diverse community sample of 241 married couples, we examined received psychological abuse (PA) as a longitudinal predictor of men's and women's sleep. Participants reported on marital functioning and mental health during three assessments (T1, T2, T3) and sleep problems during two assessments (T2, T3), with 1-year lags between waves. Growth curve analyses revealed that for both spouses, higher initial levels of PA and increases in PA over time predicted greater sleep disturbances at T3. For husbands and wives, anxiety and depression mediated some of the associations between PA and sleep problems. For wives, moderation effects highlighted the importance of violence, anxiety, and depression in exacerbating sleep problems associated with PA. Results build on and contribute significantly to the scant literature implicating the importance of the marital relationship for sleep and suggest that simultaneous consideration of intrapersonal and interpersonal variables is critical when explicating sleep disruptions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Children's emotional regulation (as indexed by vagal suppression) and children's emotional reactivity during an argument were examined as moderators and mediators of parental problem drinking and children's adjustment in a sample of 6- to 12-year-olds. Cardiac vagal tone was assessed during both a baseline condition and exposure to an audiotaped argument. Vagal suppression was calculated by subtracting vagal tone during the baseline from that recorded during the argument, with a higher number representing increased suppression of vagal tone during the argument. Emotional reactivity was based on both observations of overt behaviors of children and their reported feelings during the argument. A higher level of vagal suppression was a protective factor against children's externalizing, internalizing, and social problems associated with exposure to parental problem drinking. Emotional reactivity was a vulnerability factor, and children's increased anger and fear, and to a lesser degree sadness, each moderated and exacerbated the effects of parental problem drinking on child outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Children's vagal tone was examined as a vulnerability factor in the longitudinal relation between mothers' (MPD) and fathers' (FPD) problem drinking and children's adjustment. At T1, MPD and FPD were examined, and children's vagal tone was assessed. Two years following initial participation, child adjustment problems were evaluated. A lower level of vagal tone was a vulnerability factor for internalizing problems associated with MPD and FPD and for externalizing difficulties associated with MPD. In the context of a higher level of MPD or FPD, a lower level of vagal tone was a vulnerability factor for increases in externalizing problems over time. Results are supportive of the importance of biopsychosocial perspectives in which child characteristics interact with family risk to predict psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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