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991.
Beneficial reuse as an alternative to disposal is increasingly being considered in management of contaminated sediments dredged from harbors. The risk of metal leaching into groundwater in reuse of phosphate and thermal treated sediments was assessed with sequential extraction, synthetic precipitation leaching procedure (SPLP), and leaching as a function of pH and liquid to solid ratio (L/S). Sequential extraction revealed that phosphate addition at 5% by dry weight, followed by calcination at 700°C reduced metal association with exchangeable/carbonate and organic phases and increased that with sparingly soluble residuals. Over the pH range 4 to 9, metal leachability varied by two to four orders of magnitude while varying L/S over 5 to 100 showed little difference. The SPLP revealed that risk to groundwater criteria based on applying a dilution attenuation factor (DAF) of 13 (New Jersey) to groundwater quality levels were achieved. Risk criteria based on a DAF of 1 (Florida and Wisconsin) were exceeded for Pb, Cd, and Mn; thermodynamic analysis demonstrates that the criteria cannot be satisfied should dissolution control pore water concentrations. 相似文献
992.
993.
Sheeber Lisa B.; Johnston Charlotte; Chen Mandy; Leve Craig; Hops Hyman; Davis Betsy 《Canadian Metallurgical Quarterly》2009,23(6):871
This study examined whether parents of adolescents experiencing depressive symptoms or disorder make more negative and fewer positive attributions for their adolescents’ behavior than do parents of nondepressed adolescents, and whether parental attributions for adolescents’ behavior contribute to parenting behavior, above and beyond the adolescents’ behavior. Parents and adolescents (76 girls and 48 boys) participated in videotaped problem-solving interactions (PSIs). Each parent subsequently watched the videotape and offered attributions for their adolescent’s behavior. In addition, parent and adolescent behavior during the PSIs was coded. Mothers and fathers in families of nondepressed adolescents made significantly fewer negative attributions for their children’s behavior than did parents in families of adolescents with diagnostic or subdiagnostic levels of depressive symptoms. Moreover, mothers’ and fathers’ negative attributions were related to greater levels of observed aggressive behavior and lower levels of observed facilitative behavior during the PSIs controlling for both demographic characteristics and the relative level of adolescent aggressive and facilitative behavior during the PSI. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
The Treatment Integrity Planning Protocol (TIPP) provides a structured process for collaboratively creating a treatment integrity assessment within a consultation framework. The authors evaluated the effect of the TIPP on the implementation of an intervention designed to improve the consistency of students' mathematics performance. Treatment integrity was assessed via permanent products and teacher self-report assessments resulting from TIPP completion. Results showed that (a) 3 teachers' treatment integrity declined within the first week of implementation and increased subsequent to completion of the TIPP, (b) teachers accurately reported their level of treatment integrity, and (c) the relationship between treatment integrity and student outcomes was unclear. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Talbot Lisa S.; Hairston Ilana S.; Eidelman Polina; Gruber June; Harvey Allison G. 《Canadian Metallurgical Quarterly》2009,118(3):448
The present study investigates whether interepisode mood regulation impairment contributes to disturbances in sleep onset latency (SOL) and rapid eye movement (REM) sleep. Individuals with interepisode bipolar disorder (n = 28) and healthy controls (n = 28) slept in the laboratory for 2 baseline nights, a happy mood induction night, and a sad mood induction night. There was a significant interaction whereby on the happy mood induction night the bipolar group exhibited significantly longer SOL than did the control group, while there was no difference on the baseline nights. In addition, control participants exhibited shorter SOL on the happy mood induction night compared to the baseline nights, a finding that was not observed in the bipolar group. On the sad mood induction night, participants in both groups had shorter SOL and increased REM density when compared to the baseline nights. Bipolar participants exhibited heightened REM density compared to control participants on both nights. These results raise the possibility that regulation of positive stimuli may be a contributor to difficulties with SOL, while hyperactivity may be characteristic of REM sleep. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Stress and anxiety have been shown to increase smoking motivation. There is limited experimental data on depressed or sad mood and smoking. This study investigated the effects of two induced moods on smoking behavior. Depression scores were examined as a potential moderator and mood changes were tested as a potential mediator. Smokers (N = 121) were randomly assigned to receive either a sad induction or a neutral induction via standardized film clips. Among participants with higher depression scores, smoking duration and the number of cigarette puffs were greater in response to the sad condition. There was also a marginal interactive effect on the change in expired air carbon monoxide among this subsample; however, no differences in smoking latency or craving were observed. Changes in positive mood partially mediated the effect of condition on smoking behavior among participants with high depression scores. There was no modifying effect of gender or mediating effect of negative mood changes. The results provide preliminary support that decreases in positive mood may have a greater influence on smoking behavior among depression-prone smokers than less psychiatrically vulnerable smokers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
998.
Heyser Charles J.; McDonald Jeffrey S.; Polis Ilham Y.; Gold Lisa H. 《Canadian Metallurgical Quarterly》1999,113(1):91
The current study was conducted to characterize discriminated avoidance learning in mice by using a Y-maze task. In Experiment 1, the task parameters were manipulated, including the amount of time spent in the start arm, the amount of time to make the avoidance response, and the intertrial interval (ITI) using C57?×?SJL F1 hybrid mice. Avoidance performance was significantly improved with longer times to avoid the shock and longer ITIs. In Experiment 2, mice from 4 inbred strains (BALB/cByJ, DBA/2J, C57BL/6J, and SJL/J), an F1 hybrid (C57?×?SJL), and 1 outbred strain (CD1) were tested with various ITIs. Strain differences were observed in avoidance learning, with BALB, DBA, C57?×?SJL and CD1 mice showing significantly better avoidance learning than C57 mice, which were better than SJL mice. These data demonstrate that Y-maze performance is significantly influenced by the genetic background of the mouse and the parameters of the task. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Butler Lisa D.; Koopman Cheryl; Classen Catherine; Spiegel David 《Canadian Metallurgical Quarterly》1999,18(6):555
This study examined levels of intrusion and avoidance symptoms and their relationships to past life stress, current emotional support, disease-related variables, and age in 125 women with metastatic breast cancer. The results indicate that a sizable proportion of these women experienced clinically significant levels of intrusion and avoidance symptoms related to their cancer, particularly those with both more stressful past life events and higher current levels of aversive emotional support. Additionally, both types of symptoms were associated with shorter time since recurrence, and avoidance symptoms were associated with smaller emotional support networks. These results indicate that metastatic breast cancer is an emotionally traumatic event for a significant proportion of women, particularly those with past life stressors and unsupportive social environments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
This analysis uses data from a survey of Toronto commuter cyclists that collected information regarding accident history as well as regular commute route to work or school. By relating the route information of the 1196 respondents to facility attributes in a Geographic Information System (GIS), defensible estimates of travel exposure on roads, off-road paths and sidewalks were developed. The rate of collision on off-road paths and sidewalks was lower than for roads. The relative rates for falls and injuries suggest these events are least common on-road followed by off-road paths, and finally most common on sidewalks. The rate of major injuries, an injury that required medical attention, was greatest on sidewalks and the difference between paths and sidewalks was negligible. These rates suggest a need for detailed analysis of sidewalk and off-road path bicycle safety. The absolute event rates per bicycle kilometer were found to be between 26 and 68 times higher than similar rates for automobile travel, re-confirming the urgent bicycle safety crisis. Examination of rates for sub-groups of cyclists suggest that experience is an important factor in bicycle safety. The same survey conducted in Ottawa, Canada found event rates much lower than Toronto. This result may confirm urban form, traffic levels and attitude do affect bicycle safety. The analysis also demonstrates a successful method to quantify bicycle travel exposure information and should be considered for further use as complement to other existing techniques. 相似文献