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71.
Skinner Darlene M.; Martin Gerard M.; Scanlon Christa-Jo; Thorpe Christina M.; Barry Jeremy; Evans John H.; Harley Carolyn W. 《Canadian Metallurgical Quarterly》2001,115(1):220
The ability of rats to return to the start location was examined with a 4-arm radial water maze. The task required rats to find 2 hidden platforms in sequence. Rats were released from 1 of 3 arms and there was a platform located in the fourth arm. Once a rat found this platform, a 2nd platform was raised in another location, which was either the start location, for 1 group, or another fixed location, for a control group. Across 3 experiments, all rats learned the location of the 1st fixed platform in 80 to 120 trials. However, rats had difficulty finding a 2nd platform if it was at the start location. Control groups revealed that rats could learn 2 platform locations and that the difficulty in learning to return to the start location did not seem to be attributable to its aversive nature. In separate groups, exposure to the start location was increased by starting the rats from an initially stable platform. Rats still did not readily learn to return to the start location. The authors suggest that start location, when varied, cannot readily be used to define the location of a hidden platform. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
Carolyn V. Coulter Robin A. J. Smith Michael P. Murphy 《Fullerenes, Nanotubes and Carbon Nanostructures》2001,9(3):339-350
A monofunctionalised fullerene triphenylphosphonium salt has been synthesised to investigate the potential for adaptation of fullerenes for biological application. The redox properties of fullerenes make them effective radical scavengers and consequently they are potential antioxidants in biological systems The triphenylphosphonium moiety was chosen because this lipophilic cation increases both the solubility and membrane permeability of attached compounds, and has been used as a delivery agent in biological systems in other contexts. Furthermore, the triphenylphosphonium moiety binds tightly to cognate antibodies, facilitating linkage of attached molecules to proteins. Here we report on the interaction of a triphenylphosphonium fullerene salt with biological systems and its binding of antibodies against the triphenylphosponium moiety. 相似文献
73.
This commentary elaborates on K. D. Arbuthnott, D. W. Arbuthnott, and L. Rossiter's (2001; see record 2001-00732-001) recommendations regarding the use of imagery in psychotherapy. The reflections focus primarily on occasions when imagery may be used to help clients reprocess and work through painful or traumatic memories. Highlighted are the values of (a) developing competence before using imagery, (b) attending to issues related to informed consent and ethics, (c) integrating the use of imagery within a comprehensive assessment, (d) establishing appropriate client expectations, (e) building on information derived from less directive methods, (f) being well versed with a variety of therapeutic tools, (g) paying attention to individual differences in clients' reactions to and use of imagery, and (h) responding appropriately if clients experience spontaneous memories of unknown origin. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
Aldwin Carolyn M.; Spiro Avron; Levenson Michael R.; Bossé Raymond 《Canadian Metallurgical Quarterly》1989,4(3):295
Longitudinal changes in self-reported symptoms were investigated using the Cornell Medical Index (CMI) in a sample of 2,041 men. The average man completed 5 CMIs (range?=?2–8) over 17 (range?=?2–25) years. Using a two-stage growth model, we first regressed symptoms against time on study for each man. The average slope of physical symptoms showed a moderate increase over time, but the average slope of psychological symptoms showed little change. Next individual differences in change were examined using age at entry as an explanatory variable. Age accounted for 50% of the variance in physical symptoms at entry and 7% of the variance in slopes, but explained neither baseline level nor change in psychological symptoms. Rather, a U-shaped curve described the relation between age and psychological symptom change. These results, in concert with a developmental perspective, may help reconcile conflicting findings on aging and mental health. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Reviews the history of the issues addressed in the National Association of School Psychologists (NASP) position statement "Advocacy for the Appropriate Educational Services for All Children." Concerns about required labeling of children for services and the efficacy of resulting programs have been evident since the early years of NASP, with special emphasis since 1983. Numerous NASP activities support the objective of alternative educational service options. Implications of the Advocacy Statement for proactive initiatives are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Cunningham Michael R.; Barbee Anita P.; Pike Carolyn L. 《Canadian Metallurgical Quarterly》1990,59(1):61
The multiple motive hypothesis of physical attractiveness suggests that women are attracted to men whose appearances elicit their nurturant feelings, who appear to possess sexual maturity and dominance characteristics, who seem sociable, approachable, and of high social status. Those multiple motives may cause people to be attracted to individuals who display an optimal combination of neotenous, mature, and expressive facial features, plus desirable grooming attributes. Three quasi-experiments demonstrated that men who possessed the neotenous features of large eyes, the mature features of prominent cheekbones and a large chin, the expressive feature of a big smile, and high-status clothing were seen as more attractive than other men. Further supporting the multiple motive hypothesis, the 2nd and 3rd studies indicated that impressions of attractiveness had strong relations with selections of men to date and to marry but had a curvilinear relation with perceptions of a baby face vs a mature face. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Texture mapping is a method commonly used to increase the visual complexity of computer generated images while maintaining simplicity in the underlying geometric models. Texture maps are generally defined in two dimensional space; thus, a primary problem when applying textures to objects is determining a mapping transformation from the three dimensional space of the object to the two dimensional space of the map. A method for mapping complex polygonal geometries is presented. The algorithmunfolds the object polygon by polygon and projects the texture map onto the resulting two dimensional geometry. Enhancements to the basic unfolding algorithm either (1) control the location of map distorition introduced at areas of severe curvature or (2) average distortions over a larger area. 相似文献
78.
Two experiments examined long-term repetition priming in data entry. In each experiment, participants entered 4-digit numbers displayed as either words or numerals, and responded with digits (Experiment 1), or either digits or initial letters (Experiment 2). At test 1 week later, they entered old and new numbers, with the format changed for half of the old stimuli. Implicit memory was evidenced at test by faster entry of the old than the new numbers, regardless of whether the numbers were in the same or different format, suggesting that the abstract numerical meaning, not the surface form, contributes to repetition priming. Numbers presented as words in training had an advantage over numbers presented as numerals, regardless of response format, implying that type of processing also contributes to the effect and ruling out an explanation based on time spent processing numbers in word format. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
This study empirically identified types of African American families. Adolescents (N=111) were assessed on family functioning. With cluster analytic methods, 3 types of families were identified. The cohesive-authoritative type was above average on parental education and income, averaged about 2 children, exhibited a high quality of family functioning and high self-esteem in adolescents. The conflictive-authoritarian type had average parental education and income, an average of 2.7 children, exhibited controlling and rigid discipline, and placed a high emphasis on achievement. The defensive-neglectful type was predominately headed by single mothers with below average education and income and averaged about 3 children. Such families displayed chaotic family processes, and adolescents tended to suffer from low self-esteem. The typology exhibited good reliability. The implications of the typology are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
A group of rhesus monkeys, consisting of 8 matrilines of up to 4 generations each and 9 unrelated adult males, was studied for 2 yrs. Group size varied between 75 and 91 individuals. Data collection consisted of ad lib recording of agonistic interactions. Results indicate that adult male interference in agonistic episodes was strongly biased against adolescent and adult male participants, whereas adult female interference was biased in favor of kin and in support of younger animals against older animals. Although natal males also were biased in favor of their kin, their selective targeting of sexually mature males was independent of kinship. Adolescent males targeted adult males, but only in defense of kin. It is suggested that this selective interference against adolescent and adult males by adult males has the potential to profoundly modify male agonistic participation in intragroup encounters after puberty. Because female support is influenced primarily by kinship, females less consistently interfere against male agonistic participants. Adult males may therefore play an important role in the socialization of male agonistic expression. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献