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21.
Recent research has indicated that only a small portion of supportiveness reflects the objective properties of providers. Instead, supportiveness primarily reflects the unique relationships among specific recipients and providers (i.e., relational effects), thus suggesting new approaches to support interventions. The authors investigated the possibility that similar relational effects occur for therapy process constructs (e.g., working alliance). Isolating relational effects in psychotherapy requires that each client receive treatment from more than one therapist during the same period of time. Therefore, we conducted analog studies in which therapy clients and students viewed videos of therapists and then rated expected therapist supportiveness and expected therapy process constructs for each therapist. Two studies indicated very strong relational effects in therapist supportiveness and therapy process constructs. In addition, process constructs were correlated strongly with supportiveness (Study 1) and favorable affect (Study 2) for relational effects specifically. Implications for integrating research on perceived support and therapy process were discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
22.
The authors investigated immediate training gains, transfer effects, and 18-month maintenance after 5 weeks of computer-based training in updating of information in working memory in young and older subjects. Trained young and older adults improved significantly more than controls on the criterion task (letter memory), and these gains were maintained 18 months later. Transfer effects were in general limited and restricted to the young participants, who showed transfer to an untrained task that required updating (3-back). The findings demonstrate substantial and durable plasticity of executive functioning across adulthood and old age, although there appear to be age-related constraints in the ability to generalize the acquired updating skill. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
Modification of the human genome has immense potential for preventing or treating disease. Modern genome editing techniques based on CRISPR/Cas9 show great promise for altering disease-relevant genes. The efficacy of precision editing at CRISPR/Cas9-induced double-strand breaks is dependent on the relative activities of nuclear DNA repair pathways, including the homology-directed repair and error-prone non-homologous end-joining pathways. The competition between multiple DNA repair pathways generates mosaic and/or therapeutically undesirable editing outcomes. Importantly, genetic models have validated key DNA repair pathways as druggable targets for increasing editing efficacy. In this review, we highlight approaches that can be used to achieve the desired genome modification, including the latest progress using small molecule modulators and engineered CRISPR/Cas proteins to enhance precision editing.  相似文献   
24.
Proton acceleration from the interaction of ultra-short laser pulses with thin foil targets at intensities greater than 10(18) W cm(-2) is discussed. An overview of the physical processes giving rise to the generation of protons with multi-MeV energies, in well defined beams with excellent spatial quality, is presented. Specifically, the discussion centres on the influence of laser pulse contrast on the spatial and energy distributions of accelerated proton beams. Results from an ongoing experimental investigation of proton acceleration using the 10 Hz multi-terawatt Ti:sapphire laser (35f s, 35 TW) at the Lund Laser Centre are discussed. It is demonstrated that a window of amplified spontaneous emission (ASE) conditions exist, for which the direction of proton emission is sensitive to the ASE-pedestal preceding the peak of the laser pulse, and that by significantly improving the temporal contrast, using plasma mirrors, efficient proton acceleration is observed from target foils with thickness less than 50 nm.  相似文献   
25.
The development of a simple and feasible fluid–solid separation device is critical to further advancement in the use of micro-technology. The mini-hydrocyclone, which possesses a concise geometry and simple operational process, has been proposed as a promising solution to bridge this gap since the cut-size decreases with decreasing hydrocyclone diameter. In this work, we investigated the fluid flow and particle separation ability of a 5 mm diameter mini-hydrocyclone through computational fluid dynamics (CFD) modelling. Direct numerical simulation (DNS) results with CFD have shown that the flow transition and subsequent unsteady state behaviour occurred in the mini-hydrocyclone at a low Reynolds number (Rein = 300) because of the onset of centrifugal instability. The centrifugal instability offered an insight into the flow transition and the development of turbulent flow in hydrocyclones which have not been studied. The centrifugal instability in the mini-hydrocyclone begins as Görtler vortices developing in the boundary layer and they subsequently affect the flow field. Particle motion tracing showed that improved separation with finer cut size, d50, and steeper separation sharpness were obtained as the inlet velocity was increased. The improvement can be explained by the flow characteristics when the flow transits to turbulent flow.  相似文献   
26.
The proportion of related prime-target pairs (relatedness proportion, RP) and prime-target stimulus onset asynchrony (SOA) was varied to determine the involvement of strategic priming mechanisms in the reduction in semantic priming that occurs when a target follows an unmasked prime that itself receives immediate repetition priming from a masked prime. At 300-ms and 1,200-ms SOAs, (a) strategic semantic priming was operating, in that priming from a nonrepeated prime increased as RP increased from .25 to .75, and (b) for both RPs, prime repetition reduced semantic priming. At a 167-ms SOA, (a) priming from a nonrepeated prime was unaffected by RP, suggesting that strategic priming was not operating, and (b) for both RPs, prime repetition did not reduce semantic priming. Because prime repetition did not reduce priming at the 167-ms SOA (when only spreading activation should have been mediating semantic priming), the reduction in semantic priming produced by prime repetition is not evidence against spreading activation automaticity. Possible mechanisms through which prime repetition reduces semantic priming are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
27.
Mine Water and the Environment - Spent organic media from the vertical flow bioreactor process unit of a passive treatment system (PTS), which received acidic drainage from an abandoned coal mine...  相似文献   
28.
Oedema, due to increased vascular leakage postburn, cases significant problems for burn patients. The purpose of this study was to determine if local application of a recombinant neutral endopeptidase (rNEP) would reduce the increased vascular permeability caused by a burn. In a guinea-pig model, a single treatment of rNEP given immediately postburn significantly decreased burn-induced plasma extravasation. This rNEP effect was dependent upon both the dosage of the peptidase and its enzymatic activity. Additional experiments were consistent with the rNEP acting partly by degrading bradykinin, a mediator of increased vascular permeability postburn. These findings suggest that further study of rNEP as a possible treatment for oedema is warranted.  相似文献   
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30.
Interest in cerebrospinal fluid (CSF) lipoproteins has been stimulated by the association of certain alleles of the human apolipoprotein E gene (APOE) with an increased risk of Alzheimer's disease (AD), and because apolipoprotein E (apoE) is one of the major apolipoproteins in CSF. CSF lipoproteins (d < 1.210 g/ml fraction) are distinct from their plasma counterparts, and in AD patients CSF may contain novel particles. The protein concentration of CSF lipoproteins is reduced in AD patients. Moreover, the molecular distribution of apoE- and apoAII-containing apolipoproteins in CSF is dictated by APOE. The lipid composition suggests that CSF lipoproteins from AD patients may have undergone increased free radical-mediated damage; experimental data support the possibility that this may occur both before and after lipoprotein assembly. Finally, human CSF lipoproteins oxidized ex vivo are neurotoxic to neuronal cells in culture and disrupt microtubule structure, an activity not observed with oxidized bovine CSF lipoproteins. CSF lipoproteins may represent a means whereby apoE influences the outcome of free radical-mediated damage to brain.  相似文献   
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