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91.
Predictors of reading comprehension for struggling readers: The case of Spanish-speaking language minority learners. 总被引:1,自引:0,他引:1
This longitudinal study examined the process of English reading comprehension at age 11 years for 173 low-achieving Spanish-speaking children. The influence of growth rates, from early childhood (age 4.5 years) to pre-adolescence (age 11 years), in vocabulary and word reading skills on this complex process were evaluated with structural equation modeling. Standardized measures of word reading accuracy and productive vocabulary were administered annually, in English and Spanish, and English reading comprehension measures were administered at age 11 years. Latent growth curve analyses revealed that English skills accounted for all unique variance in English reading comprehension outcomes. Further, expected developmental shifts in the influence of word reading and vocabulary skills over time were not shown, likely on account of students' below-grade-level reading comprehension achievement. This work underscores the need for theoretical models of comprehension to account for students' skill profiles and abilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Jared J. Homola Jeannette Kanefsky Kim T. Scribner Todd G. Kalish Mark A. Tonello 《Journal of Great Lakes research》2012
The ability of fishery managers to quickly and effectively answer stakeholder questions using the best available science is crucial for successful management. The 2009 capture of a potential world record brown trout (Salmo trutta) and the 2010 capture of a potential world record land-locked Atlantic salmon (S. salar) in Michigan required managers to acquire genetic verification of the species identity. Given the variety of hatchery strains used to maintain Great Lakes fisheries for brown trout and in the absence of physical markings, managers also were interested to determine the strain of origin for information on assessing performance. DNA barcoding techniques using sequences from the mitochondrial (mt) DNA cytochrome c oxidase I (COI) gene and frequency-based analysis of species-specific microsatellite genotypes provided data to establish the species of both fish. The putative brown trout was confirmed to be a new world record specimen. Using individual assignment tests based on maximum likelihood estimators informed by multi-locus microsatellite genotypes, we determined the fish to be from the Seeforellen hatchery strain (p < 0.01). Analysis of the COI gene in the putative Atlantic salmon resulted in assignment as a brown trout. The presence of only brown trout alleles at all six microsatellite loci examined revealed that the individual was not an inter-specific hybrid. Given sufficient genetic divergence exists among species, populations, or hatchery strains, the combination of mtDNA barcoding and microsatellite genetic analysis can provide accurate and rapid identification to address stakeholder and management questions. 相似文献
93.
Freyd Jennifer J.; Pantzer Teresa M.; Cheng Jeannette L. 《Canadian Metallurgical Quarterly》1988,117(4):395
Resting objects can be described according to the physical forces operating on them, forces that are balanced in static scenes. We hypothesized that the perception of static scenes and objects might involve a representation of underlying dynamics. In our first experiments, subjects were shown a picture of a plant resting upon a table or hanging from a hook, followed by a picture of the plant in the same position without the supporting table or hook. Subjects attempted to remember the position of the plant and were then shown a third display, in which the plant was in the same position or was slightly above or slightly below the original position. Memory for the position of the previously supported object was distorted in the direction consistent with what would happen if the plant was to lose its source of support in real life. In Experiment 2 we found no memory asymmetry when the plant was initially displayed without support. We replicated the results of Experiments 1 and 2 with a new stimulus set and modified procedure in Experiment 3. In our fourth study we experimented with a slightly different stable situation: a spring with a box on top of it. We found that subjects misremembered the spring as either more compressed or less compressed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Forsythe Chris; Milliken Garrett W.; Stafford Donna K.; Ward Jeannette P. 《Canadian Metallurgical Quarterly》1988,102(3):248
The hand preferences of 5 semi-free-ranging black-and-white ruffed lemurs were assessed by using three distinct testing procedures. Testing conditions varied in the extent to which they required animals to make a whole body postural adjustment prior to making a reach. Minimal bodily adjustment was necessary for free foraging, whereas discrete food presentations on land (DFP-land) and in a moat (DFP-moat) promoted a gross reorientation of the animal's entire body. In the DFP-moat condition 4 animals exhibited exclusive use of the left hand, and only 1 of 515 reaches was made with the right hand. Similarly, all 5 animals showed a pronounced left-hand preference in the DFP-land condition. The free-foraging condition revealed a hand preference for only 1 of the 5 subjects, and that preference was weak in comparison with those measured in the other two test conditions. These findings indicate that whole body postural adjustments critically influenced the expression of hand preference and should be taken into consideration in future studies of primate hand preferences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
These notes are personal reflections, stemming from attempts to understand the sources of problems and successes in the application of work on formal specifications. Our intent is to provoke thought about the nature and value of work in the area; not to provide a set of well-tested results. Rather than focusing on yet another specification language, we have tried to take a broad view of the role of formal specifications in the program development process. 相似文献
96.
Fabian Weber Jeannette Orben Dipl.-Ing. Andreas Haus Prof. Dr.-Ing. Steffen Anders 《Beton- und Stahlbetonbau》2021,116(Z1):36-47
Concrete technological influences on the performance classes of steel fibre concrete The perfomance capacity of steel fibre reinforced concrete, expressed by its performance classes and therefor the residual flexural strength, depends on numerous factors. Including compressive strength, fibre type and geometry, fibre content and concrete composition to name a few. A working group of DAfStb subcommittee ”Stahlfaserbeton“ set up a comprehensive database containing data of numerous initial and performance tests of steel fibre reinforced concretes from publications and suppliers, especially ready mixed concrete plants. It enables us to identify specific influences, e.g. of concrete composition or fibre properties and quantify them in general. In this contribution the influence of fibre tensile strength, fibre slimness, concrete compressive strength, concrete installation consistency, the shape of aggregates as well as the usage of reactive additives are considered. Based on the database it can be seen, that no measurable effect of crushed coarse aggregates on the residual flexural strengths can be identified compared to round aggregates. The consistencies F3 and F4 of the ready mixed concrete show no significant dependency as well. The usage of secondary reactive additives, especially fly ash, as well as cement containing blast furnace slag provides higher residual flexural strengths regarding to the database. Positive influences of the compressive strength and the fibre slenderness can be generally confirmed and quantified. 相似文献
97.
Genetic differentiation among brook trout (Salvelinus fontinalis) of different life history forms and populations can result from reproductive isolation imposed by natural or anthropogenically derived barriers to gene flow, behavioral incompatibilities, or differential exposure to environmental cues. We used multi-locus microsatellite genotypes and likelihood and Bayesian-based analyses to characterize the degree of genetic differentiation and evidence of introgression among stream resident brook trout above a natural barrier, and putative stream residents and adfluvial (coaster) brook trout from below the barrier in the Salmon Trout River (STR); the sole tributary along the southern shore of Lake Superior known to be inhabited by a viable remnant population of coaster brook trout. Two genetically differentiated populations were identified, generally associated with individuals inhabiting sections of the STR above and below the falls. No evidence of differentiation was found between a priori classified resident and coaster brook trout from below the falls. Gene flow from individuals above the falls was detected based on evidence of interbreeding between upper river individuals and coasters below the falls. We collected only a relatively small number of individuals that we a priori classified as being stream residents below the falls, and these individuals had a high probability of having ancestry originating from the population above the barrier, which suggests that the stream-resident life history may be exceptionally rare or absent in the lower Salmon Trout River. 相似文献
98.
Wendy Jeannette Van Der Spuy Etheresia Pretorius 《Microscopy research and technique》2013,76(8):795-802
It is well known that estrogen is neuroprotective through various mechanisms which suggest that sex hormone levels, thrombotic mechanisms, and inflammatory processes are strongly interconnected in predicting the outcome and consequences of cerebral ischemia. Because platelet ultrastructure is altered in conditions like thrombosis and associated with stroke, the question arises whether ultrastructural analyses of platelet morphology may provide further insight into the role of estrogen during ischemic insult. In the current study, a hyperglycemic modification to the two‐vessel occlusion model for inducing experimental cerebral ischemia was employed, in order to correlate neural tissue integrity levels between three experimental groups to corresponding platelet ultrastructure so as to determine whether there is an association between cerebral ischemia and the presence of inflammatory or necrotic platelet ultrastructure. It is apparent in the results that under the influence of estrogen in cyclic or intact females, there is lesser neural tissue damage as well as a reduced degree of inflammation evident in platelet activation morphology when compared to males and acyclic or ovariectomized females. It is unmistakable that neural injury is closely shadowed, if not preceded, by inflammatory changes in the coagulation system, particularly manifested in platelet ultrastructure. It is therefore suggested that platelets may indeed be used successfully to follow the progression of events of cerebral ischemia and possibly assist in the assessment of treatment strategies and their effects on hemostasis. Microsc. Res. Tech. 76:795–802, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
99.
Van Boven Leaf; Kane Joanne; McGraw A. Peter; Dale Jeannette 《Canadian Metallurgical Quarterly》2010,98(6):872
The results of 6 experiments indicate that emotional intensity reduces perceived psychological distance. People who described events emotionally rather than neutrally perceived those events as less psychologically distant, including embarrassing autobiographical events (Experiment 1), past and future dentist visits (Experiment 2), positive and negative events (Experiment 3), and a national tragedy (Experiment 6). People also perceived an event (dancing in front of an audience) as less psychologically distant when they were in a more emotionally arousing social role (of performer) than in a less emotionally arousing social role (of observer; Experiment 4). Two findings bolster the causal role of emotional intensity in reducing perceived psychological distance. First, reported emotional intensity was negatively correlated with perceived psychological distance and statistically mediated the effect of being in an emotionally arousing social role on perceived psychological distance (Experiment 4). Second, providing people with an alternative interpretation of their emotions (emotionally ambiguous whale songs) significantly reduced, even reversed, the negative correlation between self-reported emotional intensity and perceived psychological distance (Experiment 5). These findings about emotional intensity are consistent with the broader idea that perceived psychological distance is grounded in and influenced by the phenomenology of objective distance. Implications for theories of psychological distance, emotionality, and choice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Clara Piccirillo Alessio Adamiano David M. Tobaldi Marco Montalti Jeannette Manzi Paula M. Lima Castro Silvia Panseri Monica Montesi Simone Sprio Anna Tampieri Michele Iafisco 《Journal of the American Ceramic Society》2017,100(8):3402-3414
The recovery of valuable compounds from byproducts is at present a priority topic for social, environmental, and economic reasons. In this work we report for the first time the preparation of luminescent calcium phosphate (CaP) bioceramics from waste codfish bones. Codfish bones were treated in aqueous Eu(NO3)3 solutions of different concentrations, followed by thermal treatment at either 700°C or 1100°C. The resulting materials consisted of hydroxyapatite (HAp), β‐tricalcium phosphate (β‐TCP) and a small amount of Eu2O3. Chemical and structural characterization showed that the Eu ions were successfully introduced into the bones and, hence, in the thermally treated CaP phases obtained from them, although mainly in the β‐TCP lattice. Photoluminescence investigation revealed that all the materials are luminescent, with samples treated at 1100°C having more intense luminescence than those prepared at 700°C. In vitro evaluation of cell‐materials interaction indicated that all the samples displayed good cytocompatibility toward osteoblast cells. This work demonstrates that a simple and effective process, employing Eu as a dopant, can convert fish industry byproducts into highly valuable luminescent CaP bioceramics, having potential applications in biology and medicine for bio‐imaging. 相似文献