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31.
Changing patterns of funding may require calculation of the real cost of services performed by psychology interns, including that of supportive educational and supervisory efforts. At a center with 10 interns and intensive individual supervision, the cost was approximately $13,000 per year per intern for approximately 800 hrs of direct service—an outcome that compares favorably to salaries of psychological technicians. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
32.
Data have been obtained for the kinetics of growth of the oxide film on scratched bismuth electrodes in 1.0 M NaOH solution. Growth of the oxide film occurs by a succession of two high field ion conduction mechanisms given by i = Aexp (BV/x). The results are compared with those obtained by potentiostatic pulsing of unscratched bismuth electrodes and the two types of data are in quantitative agreement.  相似文献   
33.
The segmentation of nuclear images is a crucial step in the development of procedures using image analysis for the cytological diagnosis of cancer. The purpose of this study is to evaluate the reproducibility and accuracy of several interactive segmentation methods which can be used in this context. Four methods were studied: a thresholding-based method enabling selection of intensity histogram contrast and brightness, manual tracing with a stylus, and arc- and ellipse-fitting routines. Features of nuclear size and shape were derived from nuclei segmented on repeated occasions by several individuals. Variance component models provided a statistical framework for evaluating the intraobserver and interobserver variability of these measurements in terms of their intraclass correlation coefficients. Of the methods tested, the arc-fitting segmentation method gave the most reproducible results, and thresholding the least. Reproducibility was generally very high both between individuals and for repeated segmentations by a single individual. Accuracies of area measurements for the various methods, as determined with respect to point counting, paralleled the reproducibilities of the methods. Sample size requirements were observed to be more dependent on the biological variability of the tissue sampled than on the particular segmentation method or on the number of individuals performing segmentation.  相似文献   
34.
A test and heat friction based method for evaluation of the technical condition and residual service life of machinery is presented. It is applicable for mechanisms in which friction of the moving parts leads to wear and to increased heat release. The diagnostic parameter adopted is the peak point of the temperature change rate, observed on the machine casing during the starting stage. The method was tested on the SAWA power reduction gears of KOCKS heavy portal transtainer cranes. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
35.
Reliability of the machine service life determined in a thermal diagnostic test is estimated in this investigation. The time dependence of a thermal diagnostic parameter, and the residual service life (RSL) predicted on its basis, are examined here with the aid of the Monte-Carlo simulation procedure. The relationships involved are derived from the machine heat balance under two approaches – short term (starting stage) and long term (service time). The diagnostic parameter considered is the temperature change rate during the short-term period. The constants in its expression are determined from experimental data obtained as an example on the gearboxes of three heavy portal cranes with different service times. The diagnostic parameter–time graph (long-term approach) derived from the data is used as reference for prediction of the RSL. The reference dependence obtained from theoretical values of the diagnostic parameter, and the RSL calculated from this dependence, were repeatedly varied, with a view to estimating the reliability of the prediction. The uniform and Weibull distributions were used for generating, respectively, the random fluctuations of the reference gearbox temperature and of the diagnostic parameter of the tested one. It is shown that in 95% of the cases the thermal method entails a two-sided error of at most 3.6%, and for the tested gearbox the discrepancy between the deterministic and simulated averages does not exceed 1.1%. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
36.
Serial applications (N?=?500) for service at a psychological clinic were classified on the basis of the presenting complaints to examine the nature of presenting complaints and the hypothesis of a relationship between complaints and demographic characteristics, especially gender. Such complaints proved to be highly varied, and most were unrelated to demographic variables, including gender. The relation of 5 of the 20 complaints to gender could support the theory that men are more vulnerable to performance pressures and women more subject to conflicts about dependency, perhaps for reasons related to differing social roles and expectations. The "pain potential" and "motivation potential" of complaints were assessed; contrary to expectations, neither anxiety nor depression in themselves appeared to be strong motivators for seeking psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
37.
1. The rostral ventromedial medulla (RVM) participates in the modulation of nociceptive transmission by spinal cord neurons. Previous anatomic studies have demonstrated that RVM neurons project to laminae I, II, and V of the dorsal horn; laminae VII and VIII of the intermediate and ventral horns; the intermediolateral column; and lamina X. The RVM contains at least three physiologically defined classes of neurons, two of which, the ON and the OFF cells, have been implicated in nociceptive modulation. Because these cells classes are intermingled in the RVM, it has not been possible to determine the spinal laminar projection targets of ON and OFF cells by anatomic methods. Therefore in the current study we employed antidromic microstimulation methods to determine the laminar projections of two of the three classes of RVM neurons, the ON and the OFF cells. 2. In lightly anesthetized (with methohexital sodium) rats, single-unit extracellular recordings were made from 48 RVM neurons that were physiologically characterized as ON (30) or OFF (18) cells. The recording locations of 45 of these neurons were recovered. Thirty-seven were found in the nucleus raphe magnus and eight were located near its dorsal and lateral borders. 3. Thirty-two physiologically identified RVM neurons (18 ON and 14 OFF cells) were antidromically activated from the cervical spinal cord using a monopolar stimulating electrode. The stimulating electrode was moved systematically in the white matter until antidromic activation could be produced with currents of < or = 20 microA (6.1 +/- 0.7 microA, mean +/- SE). The points from which minimum currents were required to antidromically activate the neurons were located mainly in the ipsilateral dorsolateral funiculus (DLF) (27 of 32). In a few cases, lowest antidromic threshold currents were found near the border between the DLF and ventrolateral funiculus (VLF) or, rarely, in the VLF itself. In these cases, the cell recordings were found to be near the dorsal boundary of the RVM. 4. While one electrode was used to stimulate the parent axon in the lateral funiculus, a second was used to explore the gray matter for the presence of collateral branches. The identification of a branch was initially determined by an increase in antidromic latency. At the same rostrocaudal plane of the spinal cord, stimulation of the DLF induced an antidromic spike that invaded the neuron earlier than the antidromic spike elicited by stimulation in the gray matter. Collateral branches were confirmed by establishing that the location of the minimum threshold point for antidromic activation of the neurons from the second electrode was in the gray matter, that the minimum current required to antidromically activate the neuron from that point was too low to activate the parent axon in the DLF, and that a collision occurred between the spikes induced by the two stimulating electrodes. 5. In 17 cases, physiologically identified RVM neurons (10 ON and 7 OFF cells) were antidromically activated from the gray matter of the cervical spinal cord using a current of 8.4 +/- 2.1 (SE) microA. Minimum threshold points for antidromic activation were found in laminae I-II (3 ON and 4 OFF cells), lamina V (5 ON and 6 OFF cells), and regions ventral to the lateral reticulated area (3 ON and 2 OFF cells) of the gray matter. As indicated by these numbers, some neurons were antidromically activated from more than one gray matter region. In general, all OFF cells and 9 of 10 ON cells were antidromically activated from low threshold points in either laminae I-II or lamina V. 6. In six cases, neurons were activated from separate points located in two or three different laminae of the gray matter. Three OFF cells were activated from laminae I-II and V, one OFF cell and one ON cell were activated from lamina V and from more ventral points, and one ON cell was activated from laminae I-II and from points ventral to lamina V.  相似文献   
38.
A comparison of the three-dimensional structures of the closely related mesophilic Clostridium beijerinckii alcohol dehydrogenase (CBADH) and the hyperthermophilic Thermoanaerobacter brockii alcohol dehydrogenase (TBADH) suggested that extra proline residues in TBADH located in strategically important positions might contribute to the extreme thermal stability of TBADH. We used site-directed mutagenesis to replace eight complementary residue positions in CBADH, one residue at a time, with proline. All eight single-proline mutants and a double-proline mutant of CBADH were enzymatically active. The critical sites for increasing thermostability parameters in CBADH were Leu-316 and Ser-24, and to a lesser degree, Ala-347. Substituting proline for His-222, Leu-275, and Thr-149, however, reduced thermal stability parameters. Our results show that the thermal stability of the mesophilic CBADH can be moderately enhanced by substituting proline at strategic positions analogous to nonconserved prolines in the homologous thermophilic TBADH. The proline residues that appear to be crucial for the increased thermal stability of CBADH are located at a beta-turn and a terminating external loop in the polypeptide chain. Positioning proline at the N-caps of alpha-helices in CBADH led to adverse effects on thermostability, whereas single-proline mutations in other positions in the polypeptide had varying effects on thermal parameters. The finding presented here support the idea that at least two of the eight extra prolines in TBADH contribute to its thermal stability.  相似文献   
39.
40.
The diagnostic parameter—time dependence, usually used for prediction of the residual service time, is given here its theoretical grounding. The relationships involved are derived on the basis of the machine's heat balance for two time approaches—short-term (starting time) and—long-term (service time). The diagnostic parameter considered is the temperature change rate during the running-in period of the machine. The reference dependence obtained from theoretical values of the diagnostic parameter is compared against its counterpart by the traditional empirical method. The residual service life calculated by these two approaches is also analyzed. It is shown that the theoretical consideration is valid and can be applied in reliable machine diagnostics.  相似文献   
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