全文获取类型
收费全文 | 1307篇 |
免费 | 94篇 |
专业分类
电工技术 | 4篇 |
综合类 | 4篇 |
化学工业 | 332篇 |
金属工艺 | 4篇 |
机械仪表 | 18篇 |
建筑科学 | 57篇 |
矿业工程 | 4篇 |
能源动力 | 18篇 |
轻工业 | 171篇 |
水利工程 | 20篇 |
石油天然气 | 2篇 |
武器工业 | 1篇 |
无线电 | 87篇 |
一般工业技术 | 182篇 |
冶金工业 | 345篇 |
原子能技术 | 1篇 |
自动化技术 | 151篇 |
出版年
2023年 | 15篇 |
2022年 | 56篇 |
2021年 | 73篇 |
2020年 | 28篇 |
2019年 | 35篇 |
2018年 | 37篇 |
2017年 | 31篇 |
2016年 | 56篇 |
2015年 | 42篇 |
2014年 | 55篇 |
2013年 | 67篇 |
2012年 | 66篇 |
2011年 | 111篇 |
2010年 | 92篇 |
2009年 | 74篇 |
2008年 | 70篇 |
2007年 | 84篇 |
2006年 | 48篇 |
2005年 | 52篇 |
2004年 | 50篇 |
2003年 | 27篇 |
2002年 | 26篇 |
2001年 | 20篇 |
2000年 | 18篇 |
1999年 | 13篇 |
1998年 | 12篇 |
1997年 | 18篇 |
1996年 | 12篇 |
1995年 | 13篇 |
1994年 | 12篇 |
1993年 | 9篇 |
1992年 | 5篇 |
1991年 | 2篇 |
1990年 | 5篇 |
1989年 | 6篇 |
1988年 | 10篇 |
1987年 | 8篇 |
1986年 | 6篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 6篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1979年 | 3篇 |
1975年 | 4篇 |
1973年 | 2篇 |
1964年 | 1篇 |
1961年 | 1篇 |
1960年 | 1篇 |
1958年 | 1篇 |
排序方式: 共有1401条查询结果,搜索用时 15 毫秒
101.
Structure,Protein Interactions and In Vitro Protease Accessibility of Extruded and Pressurized Full-Fat Soybean Flakes 总被引:3,自引:1,他引:2
Stephanie Jung Abdullah Mahfuz Devin Maurer 《Journal of the American Oil Chemists' Society》2009,86(5):475-483
The objectives of the present study were to determine how extrusion (barrel temperature of 100 °C) and high-pressure processing
(HPP, 200 and 500 MPa, 15 min, 25 °C) of full-fat soybean flakes (FFSF) modified the structure of soybean cotyledon cells,
the protein interactions and the in vitro protease accessibility. Cellular disruption of the cotyledon cells was only observed
for extruded FFSF. Extrusion and HPP at 500 MPa favored formation of insoluble protein aggregates, in which oil was entrapped.
High pressure size exclusion chromatography (HPSEC) and extraction methods using buffers containing SDS and 2-mercaptoethanol
suggested that noncovalent interactions were the main forces in protein aggregate formation during HPP 500 MPa and extrusion.
Intermolecular cross-linking by disulfide bonding was also involved in insoluble aggregates, but at a lesser extent than noncovalent
interactions. Extrusion and HPP 500-MPa treatment enhanced the proteolytic attack, while treatment at 200 MPa had no impact.
Drastic changes in the peptide profile of the extracted proteins were, however, only observed for the enzyme-treated 500-MPa
FFSF. Optimal oil and protein extraction yields required cellular disruption of cotyledon cells and hydrolysis of protein
aggregates, which were obtained with enzyme-assisted aqueous extraction of extruded FFSF. 相似文献
102.
Stephanie G. Adams 《工程教育杂志》2001,90(4):597-600
Within the last decade, teamwork has become a well‐known phenomenon in U.S. industry. Effective teamwork has led to an increase in productivity, a reduction in costs, a rise in employee involvement, and flattening of the organizational structure.1 This study examines students' attitudes and experiences towards working in teams, with particular attention paid to engineering students participating in entrepreneurial teams. The results of the study suggest that the students' attitudes and experiences were positive about working in teams. The majority of the students felt they were able to perform effectively in teams and thought that working in teams will be beneficial for preparing them for the workplace. Although students responded positively about their teamwork experience, only half of the students received team training. Some of the students felt indifferent about the usefulness of the team training sessions, which suggests that teamwork training needs to be improved. 相似文献
103.
Christ Mary Anne G.; Lahey Benjamin B.; Frick Paul J.; Russo Mary F.; McBurnett Keith; Loeber Rolf; Stouthamer-Loeber Magda; Green Stephanie 《Canadian Metallurgical Quarterly》1990,58(6):840
Early motherhood (r?=?.33) with the number of Diagnostic and Statistical Manual of Mental Disorders (DSM-III) symptoms of conduct disorder in a sample of 253 boys (aged 6–13 yrs) who had been referred to outpatient clinics. The following models were compared using path analysis: (1) Teenage motherhood, parental antisocial personality, and socioeconomic status (SES) each contribute uniquely to the prediction of childhood conduct problems; (2) teenage motherhood mediates the association of SES and parental antisocial personality with child conduct problems; and (3) teenage motherhood is spuriously related with child conduct problems because of common associations with SES and parental antisocial personality. Model (3) best fit the data. Similar results were obtained whether maternal age at the birth of the firstborn child or the proband child was used to define maternal age and when teenage motherhood was defined as giving birth at 相似文献
104.
Gordon Rugg Malcolm Eva Atiya Mahmood Nazia Rehman Stephanie Andrews & Sarah Davies 《Information Systems Journal》2002,12(3):215-229
Abstract. Eliciting information about organizational culture is an important part of system analysis and design. However, eliciting knowledge of this sort is difficult. Laddering is an established technique that is particularly suitable for eliciting information about goals and for eliciting explanations, which are important issues when investigating organizational culture. This paper describes the method, its strengths and limitations, its use in several case studies and its relation to other elicitation techniques. Recommendations for further work are given. 相似文献
105.
Weary Gifford; Jacobson Jill A.; Edwards John A.; Tobin Stephanie J. 《Canadian Metallurgical Quarterly》2001,81(2):206
In 3 studies, we examined the hypothesis that the effects of stereotype usage on target judgments are moderated by causal uncertainty beliefs and related accuracy goal structures. In Study 1, we focused on the role of chronically accessible causal uncertainty beliefs as predictors of a target's level of guilt for an alleged academic misconduct offense. In Study 2, we examined the role of chronic causal uncertainty reduction goals and a manipulated accuracy goal; in Study 3, we investigated the role of primed causal uncertainty beliefs on guilt judgments. In all 3 studies, we found that activation of causal uncertainty beliefs and accuracy concerns was related to a reduced usage of stereotypes. Moreover, this reduction was not associated with participants' levels of perceived control, depression, state affect, need for cognition, or personal need for structure. Results are discussed in terms of their implications for the model of causal uncertainty and, more generally, in terms of the motivational processes underlying stereotype usage. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
Nelson Charles A.; Wewerka Sandi; Thomas Kathleen M.; deRegnier Raye-ann; Tribbey-Walbridge Stephanie; Georgieff Michael 《Canadian Metallurgical Quarterly》2000,114(5):950
On the basis of animal models, it was hypothesized that infants of diabetic mothers (IDMs) would be at risk for suffering damage to the hippocampus primarily because of fetal iron deficiency, chronic hypoxia, and hypoglycemia. This, in turn, may result in impairments in recognition memory at a young age. To test this model, the memory of 6-month-old IDMs and control infants was evaluated with electrophysiological (event-related potential [ERP]) and behavioral (looking time) measures. At 12 months, the Bayley Scales of Infant Development was administered. Our ERP measures showed robust evidence consistent with memory deficits in the IDMs. In contrast, the looking time measures and the Bayley exam failed to distinguish between the groups. From these results it was concluded that the ERP, but not the behavioral, measures are able to detect, in an at-risk population, deficits in recognition memory that are thought to be mediated by damage to the hippocampus. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
Fuchs Douglas; Fuchs Lynn S.; Thompson Anneke; Otaiba Stephanie Al; Yen Loulee; Yang Nancy J.; Braun Mary; O'Connor Rollanda E. 《Canadian Metallurgical Quarterly》2001,93(2):251
The purpose of the present study was to examine the effectiveness and feasibility of phonological awareness training, with and without a beginning decoding component. 33 teachers in 8 urban schools were assigned randomly within their schools to 3 groups: control, phonological awareness training, and phonological awareness training with beginning decoding instruction and practice. Following training, teachers in the 2 treatment groups conducted the treatments for about 20 wks. In each teacher's class, pre- and posttreatment data were collected on 12–14 children (N?=?404); 312 children were tested again the following fall. At the end of kindergarten, the 2 treatment groups performed comparably and outperformed controls on the phonological awareness measures. On alphabetic (reading and spelling) tasks, however, the group participating in phonological awareness training with beginning decoding instruction did better than the other 2 groups. In the fall of the next year, many of these between-group differences remained but were less impressive. Implications are discussed for bridging research and practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
The clinical efficacy of cognitive behavior therapy (CBT) for chronic insomnia has been established, yet clinical effectiveness is less clear. This study presents data on 109 patients from general practice during a formal evaluation of clinical effectiveness. Two thirds achieved normative values of ≤30 min for sleep latency and wakefulness during the night after CBT. Furthermore, almost half of the sample reduced sleeplessness by ≥50%. Logistic regression revealed that initial severity did not contraindicate good outcome. Rather, greater sleep disturbance was positively associated with large symptom reduction, although lower endpoint scores were less likely. Similarly, symptoms of anxiety, depression, and thinking errors positively predicted good outcome. Hypnotic using patients responded equally well to CBT, and demographic factors were of no significant predictive value. It is concluded that CBT is clinically and durably effective for persistent insomnia in routine practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
Forgas Joseph P.; Bower Gordon H.; Moylan Stephanie J. 《Canadian Metallurgical Quarterly》1990,59(4):809
Three experiments showed that mood influences achievement attributions and that cognitive processes underlie these effects. In Experiment 1, happy Ss made more internal and stable attributions for success than failure in typical 'life dilemmas.' In Experiment 2, attributions for real-life exam performance were more internal and stable in a happy than in a sad mood. Dysphoric moods resulted in self-critical rather than self-enhancing attributions, contrary to motivational theories, but consistent with cognitive models and the clinical literature on depression. In Experiment 3 this pattern was repeated with direct self vs. other comparisons, and for self-efficacy judgments. The results are interpreted as supporting cognitive rather than motivational theories of attribution biases. The implications of the results for clinical research, and contemporary affect–cognition theories are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
Conditions which facilitate clients' outgrowing disturbing dreams are discussed. Several incidents with clients describe these conditions and illustrate their facilitative power. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献