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51.
Sounds such as co-workers chatting nearby or a dripping faucet help us maintain awareness of and respond to our surroundings. Without a tool that communicates ambient sounds in a non-auditory manner, maintaining this awareness is difficult for people who are deaf. We present an iterative investigation of peripheral, visual displays of ambient sounds. Our major contributions are: (1) a rich understanding of what ambient sounds are useful to people who are deaf, (2) a set of visual and functional requirements for a peripheral sound display, based on feedback from people who are deaf, (3) lab-based evaluations investigating the characteristics of four prototypes, and (4) a set of design guidelines for successful ambient audio displays, based on a comparison of four implemented prototypes and user feedback. Our work provides valuable information about the sound awareness needs of the deaf and can help to inform further design of such applications.  相似文献   
52.
This article explores ways in which some of what has been achieved through the use of writing can be achieved in the domain of the oral and ways in which the use of oral forms might be revalued as literate composition. Toward these ends, I introduce a new word and practice to provide a counterpart to writing in a spoken modality: Spriting in its general form is the activity of speaking “on the record” that yields a technologically supported representation of oral speech with essential properties of writing, such as permanence, and offers possibilities of editing, indexing, and scanning but without the difficult transition to a deeply different form of representation such as writing itself. Literacy is defined here as the sophisticated structures and elements that characterize linguistic stories and ideas, largely but not completely independent of the material ways in which these structures are realized. That is, this article distinguishes literacy from letteracy, which refers to textual decoding and encoding abilities, and I introduce another new term, prosodacy, which refers to oral decoding and encoding abilities. Based on outcomes from two years of exploratory empirical work with adult learners and young children using novel spriting software I designed and developed for them, I discuss four areas in which spriting-like activities and technology can have a positive impact on literacy development and education.  相似文献   
53.
The relationship between age, relative numerousness judgment, and summation was investigated in 11 Western lowland gorillas (Gorilla gorilla gorilla). Experiments 1 and 2 evaluated the gorillas' ability to select the larger of 2 food quantities before and with training. The majority of gorillas did not reliably select the larger quantity in Experiment 1 until receiving training to do so in Experiment 2. Experiment 3 evaluated their ability to select the larger of 2 pairs of quantities. All gorillas selected the larger pair more often than chance, and the old were less accurate and slower than were the young. For most gorillas, performance in relative numerousness judgment with training and summation was comparable with previous reports in chimpanzees and orangutans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
54.
The effects of time-of-day preferences on selective attention were tested in 2 experiments after normative work with 975 younger adults and 143 older adults verified C. P. May, L. Hasher, and E. R. Stoltzfus's (1993) finding that most older adults prefer the morning, whereas younger adults prefer activities later in the day. In Experiment 1, the cognitive effects of testing at preferred or nonpreferred times of day were examined in negative priming and related paradigms because (a) older adults typically have not shown negative priming and (b) previous research has not taken preference and testing times into account. In contrast to those tested at nonpreferred times, both younger and older groups tested at their preferred times showed negative priming. Age or testing optimality also affected other priming tasks. The central results were replicated in Experiment 2, which tested younger and older adults at their preferred times of the middle of the day. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
55.
Zebra mussels, Dreissena polymorpha, invaded Green Bay, Lake Michigan in the early 1990s. In 1986, prior to zebra mussel invasion, the Green Bay Metropolitan Sewerage District initiated a long-term water quality monitoring program involving 12 stations in three distinct zones along a trophic gradient in lower Green Bay. We analyzed this data set pre and post invasion using various regression models to determine the impacts of the zebra mussel on water clarity, nutrient concentrations, and the relationship between chlorophyll and phosphorus in this system. Following zebra mussel invasion, Secchi depths did not change in all three zones. Chlorophyll a concentrations decreased post zebra mussels in all zones. These differences were attributed to the filter feeding abilities of zebra mussels. Lower Green Bay exhibits a strong trophic gradient and zebra mussel impacts on the chlorophyll-phosphorus relationship differed between the three zones. We saw no changes in the chlorophyll-phosphorus relationship in zone 1, zone 2 appeared to be a transition zone with slight changes in the chlorophyll-phosphorus relationship, and in zone 3 there was evidence of an altered chlorophyll-phosphorus relationship post zebra mussels. These results indicate that the impact of zebra mussels on water quality parameters and on chlorophyll-phosphorus dynamics may differ depending on initial trophic status and on zebra mussel densities.  相似文献   
56.
The release of suspended particulate matter (SPM) in the indoor environment from the combustion of fuelwood, agri-residue, dung cakes and a mixture of fuelwood and dung cakes in traditional as well as improved biomass cookstoves is studied. The SPM emission is monitored at two positions in the kitchen and also at the centre of the living room. A comparative performance evaluation of several biofuel-cookstove combinations is undertaken. Some important results are plotted graphically and briefly discussed.  相似文献   
57.
In 2 samples of sons of alcoholics (family history positive for alcoholism; FHP: N?=?74 & N?=?72), cluster analyses identified 3 subtypes of familial vulnerability: 1 with low levels of familial psychopathology (FHP-LP) and moderate levels of familial alcoholism; a 2nd with high levels of familial antisocial personality (FHP-ASP), violence, and alcoholism; and a 3rd with high levels of familial depression (FHP-DEP), mania, anxiety disorder, and alcoholism. Compared with family history negative (FHN) participants (N?=?106), FHP offspring had higher levels of alcohol problems. FHP-ASP offspring had elevated levels of antisocial traits and negative affect. Compared with FHN participants, FHP-DEP offspring elevated levels of antisocial traits, hypomania, and experience seeking. FHP-LP offspring had moderate levels of antisocial traits. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
59.
Multi‐walled carbon nanotubes (CNTs) and cellulose nanofibers (CNFs) reinforced shape memory polyurethane (PU) composite fibers and films have been fabricated via extrusion and casting methods. Cellulose nanofibers were obtained through acid hydrolysis of microcrystalline cellulose. This treatment aided in achieving stable suspensions of cellulose crystals in dimethylformamide (DMF), for subsequent incorporation into the shape memory matrix. CNTs were covalent functionalized with carboxyl groups (CNT‐COOH) and 4,4′‐methylenebis (phenylisocyanate) (MDI) (CNT‐MDI) to improve the dispersion efficiency between the CNT and the polyurethane. Significant improvement in tensile modulus and strength were achieved by incorporating both fillers up to 1 wt% without sacrificing the elongation at break. Electron microscopy was used to investigate the degree of dispersion and fracture surfaces of the composite fibers and films. The effects of the filler (type and concentration) on the degree of crystallinity and thermal properties of the hard and soft segments that form the PU sample were studied by calorimetry. Overall, results indicated that the homogeneous dispersion of nanotubes and cellulose throughout the PU matrix and the strong interfacial adhesion between nanotubes and/or cellulose and the matrix are responsible for the enhancement of mechanical and shape memory properties of the composites. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers  相似文献   
60.
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