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291.
A report of numerosity task was used in 2 experiments to examine the effect of inherent stimulus organization on the report accuracy of 2 S groups. Ss in each experiment were 10 schizophrenics and 10 drug abusing inpatients (controls). In both experiments, displays containing from zero to 6 lines were presented tachistoscopically. In Exp I, the lines appeared either alone or with noise elements (circles). When the lines appeared alone, schizophrenics and controls performed comparably. Their report accuracy decreased with increases in the number of lines. In the noise condition, the level of performance dropped only for schizophrenics. In Exp II, the stimulus arrays did not contain noise elements. Ss were given the task of reporting all the lines they saw. The perceptual organization of the arrays was manipulated by varying the similarity and proximity of the line elements. The performance of controls deteriorated as the organization of the arrays became more complex; schizophrenics were not affected by the organization. In fact, their average performance was significantly better than that of controls. Results of the 2 experiments are interpreted as evidence that schizophrenics' perceptual deficit lies in a failure to organize information at an early stage in processing. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
292.
Penicillin injected to rats in high doses at various periods of pregnancy produced no negative effect on the devloping fetus and neonate. At the same time bicillin-3 produced resorption of the embryonic cells and had a negative effect on the heart development.  相似文献   
293.
Leiomyoma of the ciliary body of the eye was studied with the help of optical microscope at the ultrastructural level. The tumour was characterized by 4 types of cells: micro immature myoblasts, macro differentiated myoblasts, dystrophically changed muscle cells with lipofuscin inclusions, and fibroblasto-like cells. At the luminous level the differentiation of pigmental granules of melanin and lipifuscin was impeded. At the ultrastructural level they had different morphology, and therefore the differential diagnosis of a slightly pigmented melanoma and leiomyoma is possible.  相似文献   
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Test results and an evaluation of the two-parameter fracture criterion (TPFC) are presented. The tests were conducted at room temperature with annealed Type 304 stainless steel flat-plate tensile specimens containing triangular-, ellipsoidal- or rectangular-shaped surface flaws, and pressurised pipe specimens with internal or external triangular-shaped surface defects. Generally accepted analytical techniques are not available for these and other very ductile materials used in many nuclear reactor components and an accurate assessment of the influence of defects on structural component integrity is needed.The TPFC approach was used in conjunction with the initial defect size and the loads required for the initiation of subcritical crack growth, for penetration through the wall thickness and for instability. Generally, the test results obtained from the flat specimens could be used to predict, from a conservative point of view, the behaviour of pipe specimens. Since KF is thickness dependent, it is recommended that tests be conducted for the specific thickness of concern using specimens containing surface defects. The TPFC approach can provide an accurate means for predicting structural integrity.  相似文献   
297.
Reading aloud and recognition reading were examined in a paralexic patient. Certainty ratings made by the patient during oral reading indicated that he was usually unaware of paralexic errors which he made. In an auditory recognition reading task for words previously misread, the patient still performed poorly, often chosing his paralexic response as the correct alternative. Possible mechanisms underlying paralexia are discussed in the light of these findings.  相似文献   
298.
Heating and cooling loads have been calculated for a prototype residential building at different orientations, using a development version of the building energy analysis computer program BLAST. The study was carried out for 25 climates in the United States. It was found that in all climates, when the more extensively glazed exposure is oriented to south, total loads are significantly lower than those in the same building oriented east or west. North orientation also produces lower total loads than east or west orientations in the southern two-thirds of the U.S., and roughly equivalent loads in the northern third. Total loads are higher for north than south orientation except in extreme southern latitudes of the U.S. (those areas with dominant cooling loads). Variation of peak loads in response to orientation and sensitivity of results to (1) total window area and its distribution, (2) size of window overhangs, and (3) level of thermal mass are reported.  相似文献   
299.
Nitrogen response of maize under temporary flooding   总被引:1,自引:0,他引:1  
The adverse effect of temporary flooding on maize (Zea mays L.) yields and the nitrogen management required to mitigate the effect of flooding were studied for five years in field experiments on Choa sandy loam soil.Maize yields decreased with increase in duration of flooding and with decrease in the age of the crop at the time of flooding. Flooding periods exceeding 48 hours caused significant crop damage. The loss in yield on account of flooding was, however, less in 40-day old crops. A 24 hours flooding decreased grain yield by 17.7 and 3.9 per cent in 20-day and 40-day old crops respectively. Maximum yield loss amounted to 1.23 t ha–1 of grains with 72 hours of flooding of 20-day old crop indicating that a younger crop is more prone to the deleterious effect of flooding.The nitrogen content of grains decreased significantly with increase in flooding period. A supplemental dose of 7 kg N ha–1 as urea spray significantly increased grain yield. Soil application of supplemental nitrogen at the rate of 14 or 20 kg N ha–1 enhanced the maize yield by 0.7 to 0.9 t ha–1 under temporary flooded conditions. Spraying with urea solution increased nitrogen removed by the crop.Successive increments of 60 kg N ha–1 gave an additional yields of 1.23, 1.01 and 0.41 t ha–1 over the crop that received no nitrogen. Flooded maize responded to even higher rates of N fertilization than the dose of 120 kg N ha–1 which is recommended in this region.  相似文献   
300.
Seasonal variation in prepubertal penile growth has not previously been studied. The present study assessed the influence of daylength and androgens on penile development in the Siberian hamster (Phodopus sungorus). Adult penile masses were achieved at 18 and 8 weeks of age in hamsters maintained from birth under short (10 h light:14 h dark) versus long (14 h light:10 h dark) daylengths, respectively. Insulin-like growth factor I concentrations, previously implicated in penile growth, did not differ between hamsters maintained in short versus long daylengths. Gonadectomized juvenile males maintained in short and long daylengths and administered testosterone attained adult penile masses well in advance of untreated gonad-intact males maintained in short daylengths. Hamsters from both photoperiods, castrated as juveniles and first treated with testosterone in adulthood, also achieved adult penile masses. The photoinhibited gonad is insufficient to promote penile growth, and prepubertal gonadal secretions during short daylengths are not necessary for eventual penile development. Among young born near the end of the mating season, onset of neuroendocrine refractoriness to short daylengths at about 100 days of age and subsequent gonadal development induces growth in all reproductive tissues. Timing of puberty and increased androgen secretion controlled by daylength are the primary determinants of postnatal penile growth, which may also be affected by prenatal and early postnatal organizational actions of androgens.  相似文献   
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