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81.
European policy is focusing on innovation as a way out of the economic crisis. At the same time, job insecurity is rising as Europe is still in crisis. In this paper, we examine whether job insecurity affects the innovative work behaviour of employees by focusing on the relation between job insecurity, job autonomy, work engagement and innovative work behaviour (IWB). Using employee level survey data, we use structural equation modelling to disentangle the relations between these variables. The partially mediated model shows the best fit with the data. This model shows that job insecurity and autonomy are both directly and indirectly, through work engagement, related with IWB. For autonomy these relations are positive, while they are negative (and smaller) for job insecurity. Moreover, a negative covariance is observed between job insecurity and autonomy.  相似文献   
82.
Properties of a single-chain antibody containing different linker peptides   总被引:1,自引:0,他引:1  
Single-chain antibodies were constructed using six differentlinker peptides to join the VH and VL domains of an anti-2-phenyloxazolone(Ox) antibody. Four of the linker peptides originated from theinterdomain linker region of the fungal cellulase CBHI and consistedof 28, 11, six and two amino acid residues. The two other linkerpeptides used were the (GGGGS)3 linker with 15 amino acid residuesand a modified IgG2b hinge peptide with 22 residues. Proteolyticstability and Ox binding properties of the six different scFvderivatives produced in Escherichia coli were investigated andcompared with those of the corresponding Fv fragment containingno joining peptide between the V domains. The hapten bindingproperties of different antibody fragments were studied by ELISAand BIAcoreTM. The interdomain linker peptide improved the haptenbinding properties of the antibody fragment when compared withFv fragment, but slightly increased its susceptibility to proteases.Single-chain antibodies with short CBHI linkers of 11, six andtwo residues had a tendency to form multimers which led to ahigher apparent affinity. The fragments with linkers longerthan 11 residues remained monomeric.  相似文献   
83.
Simultaneous Hall and conductivity measurements have been performed on sputtered polycrystalline thin films and on bulk ceramic specimens of nearly stoichiometric CeO2 in the temperature range between 900° and 1040°C. The measurements have been performed in air using low-frequency alternating current. In the case of the bulk ceramic specimens, an upper limit for the carrier mobility of ≤0.2 cm2/(V·s) has been obtained, which is in accordance with data from the literature for bulk samples. The conductivity of the thin films (l/1Ω·m) at 1000°C) is in accordance with data from the literature for bulk ceramics. The carrier density derived from the Hall measurements (3 × 1016/cm3 at 1000°C) increases with increasing temperature, whereas the Hall mobility (4 cm2(V·s) at 1000°C) decreases with increasing temperature. These values differ from literature data for bulk ceramic specimens. The difference may be duelo the small grain diameters (∼200 nm) in the 1-μm-thick thin films.  相似文献   
84.
Induction of systemic resistance to feeding of beet armyworm, Spodoptera exigua, was investigated in two isogenic lines of Stoneville 213 cotton, Gossypium hirsutum, that differed in the presence of pigment glands. In laboratory bioassays, larvae strongly preferred to feed on glandless cotton plants when presented a choice between undamaged terminal leaves of undamaged glanded and glandless plants. Feeding damage inflicted by S. exigua larvae on the two oldest leaves of glanded plants seven days prior to feeding bioassays caused larvae to prefer by 33-fold the undamaged terminal foliage from undamaged plants compared to that from damaged plants. Feeding damage on glandless plants caused only a 2.6-fold greater preference for terminal foliage from undamaged plants over foliage from previously damaged plants. Extracts of terminal foliage from glanded cotton damaged seven days earlier had significantly greater quantities of terpenoid aldehydes (hemigossypolone, gossypol, and heliocides) than did foliage from undamaged glanded plants. Terpenoid aldehydes were undetectable in extracts of both undamaged and previously damaged glandless plants. The profile of volatile compounds collected from the headspace of mechanically damaged terminal leaves of undamaged glanded and glandless plants differed. Both cotton isolines released large quantities of lipoxygenase products (hexenyl alcohols, acetates, and butyrates), but glandless plants released only small amounts of mono- and sesquiterpenes compared to glanded plants. Glandless plants damaged seven days prior to volatile collection released significantly greater quantities of lipoxygenase products, -ocimene, and - and -farnesene than did undamaged glandless plants. Previously damaged glanded plants released significantly greater quantities of all mono- and sesquiterpenes and hexenyl acetates and butyrates, but not alcohols. The relative importance of volatile compounds versus terpenoid aldehydes in induced feeding deterrence in cotton to S. exigua larvae is still unclear.  相似文献   
85.
Experimental permittivity data of liquid water, compiled from the open literature, were selectively applied to support a modeling strategy. Frequencies up to 1 THz and atmospheric temperatures are covered with an expression made up by two relaxation (Debye) terms. The double-Debye model reduces to one term when the high frequency limit is set at 100 GHz, and the model can be extended to 30 THz by adding two resonance (Lorentzian) terms. The scheme was carried out by employing nonlinear least-squares fitting routines to data we considered reliable.  相似文献   
86.
ABSTRACT

We combine satellite imagery, urban growth modelling, groundwater modelling and hydrogeological field expeditions to estimate the potential impacts in 2050 of rapid urbanization and climate change on groundwater in Arusha, Tanzania, and by extension similar areas in Sub-Saharan Africa. Our analysis suggests that a reduction of groundwater recharge by 30–44% will cause groundwater levels to drop by up to 75 m, mainly due to increased evapotranspiration and to an expansion in paved surface. If this scenario becomes reality, we predict that wells will run dry, creating health, social and environmental risks.  相似文献   
87.

Definition of the problem:

Being satisfied with one’s work depends on professional autonomy, which is attributed to the medical profession to a high degree, combined with specialized knowledge and moral authority for vital questions. That is why physicians enjoy a high reputation. At the beginning of a person's medical career, moral competence is developed nearly completely, but specialized knowledge must be learned. Hospitals, in which further medical education regularly takes place, are still traditionally hierarchically organized today. Unfortunately, feudalistic or military structures hinder autonomous moral decisions and cause structural irresponsibility.

Arguments:

Obstructions and pressure by superiors, financial restrictions, arrogance and trying to make one's mark are shown in typical conflict situations. Stress, discontent, moral conflicts and illness, even including burn out are possible. Commitment and creativity by employees are prevented and mistakes cannot be constructively managed. Thus, patients may suffer unreasonably or be hurt.

Conclusion:

There is a risk to subordinate moral principles under other interests, not only with subordinates but also with superiors. Ways to create a culture that promotes autonomy among physicians and between different professions are discussed. Therefore it is necessary to institutionalize communication based on a reciprocal high regard in a team with people treated as equal partners, who are then able to discuss moral questions in a discourse.  相似文献   
88.
In this study, the underlying mechanism for improved spinnability when mixing lignin and cellulose in solution was investigated. Co-processing of lignin and cellulose has previously been identified as a potential route for production of inexpensive and bio-based carbon fibers. The molecular order of cellulose contributes to the strength of the fibers and the high carbon content of lignin improves the yield during conversion to carbon fibers. The current work presents an additional benefit of combining lignin and cellulose; solutions that contain both lignin and cellulose could be air-gap spun at substantially higher draw ratios than pure cellulose solutions, that is, lignin improved the spinnability. Fibers were spun from solutions containing different ratios of lignin, from 0 to 70 wt%, and the critical draw ratio was determined at various temperatures of solution. The observations were followed by characterization of the solutions with shear and elongational viscosity and surface tension, but none of these methods could explain the beneficial effect of lignin on the spinnability. However, by measuring the take-up force it was found that lignin seems to stabilize against diameter fluctuations during spinning, and plausible explanations are discussed.  相似文献   
89.
Journal of Chemical Ecology - There is increasing evidence that microorganisms, particularly fungi and bacteria, emit volatile compounds that mediate the foraging behaviour of insects and therefore...  相似文献   
90.
Objective

Image post-processing corrects for cardiac and respiratory motion (MoCo) during cardiovascular magnetic resonance (CMR) stress perfusion. The study analyzed its influence on visual image evaluation.

Materials and methods

Sixty-two patients with (suspected) coronary artery disease underwent a standard CMR stress perfusion exam during free-breathing. Image post-processing was performed without (non-MoCo) and with MoCo (image intensity normalization; motion extraction with iterative non-rigid registration; motion warping with the combined displacement field). Images were evaluated regarding the perfusion pattern (perfusion deficit, dark rim artifact, uncertain signal loss, and normal perfusion), the general image quality (non-diagnostic, imperfect, good, and excellent), and the reader’s subjective confidence to assess the images (not confident, confident, very confident).

Results

Fifty-three (non-MoCo) and 52 (MoCo) myocardial segments were rated as ‘perfusion deficit’, 113 vs. 109 as ‘dark rim artifacts’, 9 vs. 7 as ‘uncertain signal loss’, and 817 vs. 824 as ‘normal’. Agreement between non-MoCo and MoCo was high with no diagnostic difference per-patient. The image quality of MoCo was rated more often as ‘good’ or ‘excellent’ (92 vs. 63%), and the diagnostic confidence more often as “very confident” (71 vs. 45%) compared to non-MoCo.

Conclusions

The comparison of perfusion images acquired during free-breathing and post-processed with and without motion correction demonstrated that both methods led to a consistent evaluation of the perfusion pattern, while the image quality and the reader’s subjective confidence to assess the images were rated more favorably for MoCo.

  相似文献   
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