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61.
5-[4-(2-Carboxyethylcarbamoyl)phenylazo]salicylic acid disodium salt dihydrate (CAS 80573-04-2, BX661A) is developed as a therapeutic agent for ulcerative colitis. To clarify the mechanisms of action of BX661A, the effects of BX661A and its metabolites 5-aminosalicylic acid (5-ASA) and 4-aminobenzoyl-beta-aline (4-ABA) on polymorphonuclear (PMN) leukocyte chemotaxis and production of reactive oxygen species (ROS) from PMN cells were investigated and compared with the effects of 2-hydroxy-5-[[4-[(2-pyridinylamino)sulfonyl]phenyl]azo]-benzoic acid (CAS 599-79-1, SASP) and its metabolite 4-amino-N-2-pyridinyl-benzenesulfonamide (CAS 144-83-2, SP). 1. BX661A, SASP and SP concentration-dependently inhibited guinea pig PMN cell chemotaxis induced by zymosan-activated serum (IC50 = 1.39, 2.17 mmol/l, respectively) and by N-formyl-methionyl-leucyl-phenylalanine (FMLP) with IC50 values of 0.55, 0.06 and 0.66 mmol/l, respectively. 5-ASA and 4-ABA weakly affected the PMN cell chemotaxis induced by zymosan-activated serum (both IC50 values > or = 10 mmol/l) and by FMLP (IC50 > or = 10 and 8.05 mmol/l, respectively). 2. BX661A, SASP and SP concentration-dependently inhibited human PMN cell chemotaxis induced by FMLP with IC50 values of 0.68, 0.05 and 2.68 mmol/l, respectively, but both IC50 values of 5-ASA and 4-ABA were > 10 mmol/l. 3. BX661A, SASP, 5-ASA, 4-ABA and SP inhibited ROS production from rat PMN cells stimulated by FMLP in a concentration-dependent manner (IC50 = 58.4, 27.5, 0.61, 1242 and 13.9 mmol/l, respectively). 4. BX661A, SASP, 5-ASA, 4-ABA and SP inhibited ROS production from human PMN cells stimulated by FMLP in a concentration-dependent manner (IC50 = 67.4, 46.1, 0.69, 748 and 8.31 mumol/l, respectively). These results suggest that BX661A itself has inhibitory effects against PMN cell chemotaxis and ROS production from PMNs and that 5-ASA, which is the active moiety of BX661A, has a potent inhibitory effect against ROS production from PMNs. Therefore, these effects may be partially involved in the therapeutic effects of BX661A on ulcerative colitis.  相似文献   
62.
63.
E.D. Doyle  D.M. Turley 《Wear》1978,51(2):269-278
Delamination of the surface layers of brass workpieces was observed during single-grit grinding. In most instances, complete delamination did not occur and the delaminated material was still attached to the workpiece. Transmission electron microscope examination of the ground surface layers showed that they had a fine subgrain structure; no evidence of a dislocation-free surface layer was obtained. Delamination was found to occur in the fine-grained surface layers, and it is suggested that this occurs by a process of shear separation within the fine subgrain structure. The manner in which the delaminated sheets were observed to lift away from the workpiece surface seems to indicate the presence of both residual tensile and compressive stresses within the surface layers.  相似文献   
64.
Studied the conditions under which failure would enhance or inhibit subsequent task performance. Based on the theory of C. B. Wortman and J. W. Brehm (1975), it was expected that small amounts of failure would produce reactance (manifested by improved performance at a subsequent task); large amounts would lead to learned helplessness (i.e., impaired later performance). It was further expected that individual differences in self-esteem and private self-consciousness would serve as moderator variables for the effects. In Exp I, 78 college students were exposed to either a small amount or no failure before working on an anagrams task. As predicted, Ss high in self-consciousness, who showed greater reactance arousal in attitude change studies, performed better on the anagrams task than Ss low in self-consciousness in the small-failure condition, but not in the no-failure condition. In Exp II, 119 Ss were pretreated with either a small amount of failure, an extended amount of failure, or no failure before working on the task. A significant Self-Esteem by Helplessness Training interaction emerged. Low self-esteem Ss (low SEs) performed marginally better than did high SEs in the small-failure condition but significantly worse than high SEs in the extended-failure condition. Questionnaire data from Exp II were consistent with the notion that enhanced performance reflected reactance, whereas impaired performance signified helplessness. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
65.
Many of today's and tomorrow's applications require the increased performance of a multiple windows terminal. There are four choices for IS managers who want to advise their operations or administrative staff on a multiple windows capability. This article compares and contrasts the options to help IS managers choose among them and meet the goal of increasing the productivity of business users.  相似文献   
66.
This study examined 2- to 3-month-olds' representations of bisyllables. In 3 experiments, infants were familiarized with sets of bisyllables that either did or did not share a common consonant–vowel (CV) syllable. In Experiment 1, infants detected the presence of a new bisyllable in the test phase except when it shared a common initial CV syllable. A modified version of the high-amplitude sucking procedure, incorporating a 2-min delay period, tested infants' retention of information about bisyllables in the remaining 2 experiments. In Experiment 2, infants were significantly more likely to retain information about bisyllables that shared the same initial CV syllable. Finally, the authors investigated whether infants simply benefited from the presence of 2 common phonetic segments, regardless of whether these came from the same CV syllable. The results showed that CV syllable organization is important in infants' ability to encode and retain information about bisyllables. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
67.
Differences in decision making styles and decision settings have motivated the development of a variety of interactive approaches to assist decision makers (DMs) in determining preferred solutions to multiple criteria decision making problems. This paper presents a Simplified Interactive Multiple Objective Linear Programming (SIMOLP) procedure which is designed to appeal to a broad range of DMs because of its simplicity and flexibility. Specifically, at any stage in the interactive process, the procedure attempts to
1. (1) minimize the inputs required from the DMs;
2. (2) provide DMs with a representative set of decision alternatives while simultaneously limiting the number of alternatives considered; and
3. (3) allow DMs to change their minds about previously eliminated alternatives. The procedure is illustrated with both graphical and numerical examples and computational experience is discussed.
  相似文献   
68.
In Experiment 1, female Betta given daily injections of testosterone (T) for 9 weeks acquired anatomical features characteristic of males as indicated by changes in fin length, body coloration, and gonadal morphology. These findings suggested that a potential for sex reversal exists in females of this species. In Experiment 2 we measured changes in aggressive behavior during testosterone-induced anatomical changes. Aggression decreased toward females and increased toward males as treatment with T progressed. The final displays of aggressive behavior and anatomical characteristics of fish injected with T resembled those of typical males. In Experiment 3, female Betta primed with T injections for 3 or 6 weeks and permitted to interact socially with females continued to display characteristics of sex reversal after T supplementation ceased. Sex reversal in isolated fish injected with T for 3 or 6 weeks was not sustained, and fish receiving only the control vehicle showed negligible change in both the isolated and community conditions. We discuss the results in terms of similarities with the sex change process found in isolated communities of coral reef fish. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
69.
A theory is presented for waveguiding in inverted rib waveguide (IRW) lasers. For the first time, theory has been compared with experiment for these structures in (In, Ga)(As, P). Consideration is given to dielectric constant models in the quaternary system. After including the large negative effect of carriers on the dielectric constant, the modified single effective oscillator model is found to be suitable. By applying the dielectric constant values so obtained to the waveguide theory, IRW design curves are produced. Measurements of lateral far-field widths and spectral separations of zero and first order modes are used to test the validity of the predictions. The agreement is very good. The guide strengths are in the rangeDelta epsilon_{G} = 3-11 times 10^{-2} (Deltan_{G} = 5-17 times 10^{-3}).  相似文献   
70.
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