首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   895篇
  免费   45篇
  国内免费   21篇
电工技术   19篇
综合类   34篇
化学工业   87篇
金属工艺   21篇
机械仪表   37篇
建筑科学   95篇
矿业工程   21篇
能源动力   14篇
轻工业   33篇
水利工程   5篇
石油天然气   8篇
武器工业   7篇
无线电   49篇
一般工业技术   91篇
冶金工业   382篇
原子能技术   7篇
自动化技术   51篇
  2024年   3篇
  2023年   13篇
  2022年   19篇
  2021年   22篇
  2020年   18篇
  2019年   23篇
  2018年   19篇
  2017年   24篇
  2016年   29篇
  2015年   22篇
  2014年   28篇
  2013年   35篇
  2012年   42篇
  2011年   90篇
  2010年   63篇
  2009年   70篇
  2008年   59篇
  2007年   50篇
  2006年   65篇
  2005年   51篇
  2004年   40篇
  2003年   44篇
  2002年   40篇
  2001年   33篇
  2000年   5篇
  1999年   6篇
  1998年   7篇
  1997年   2篇
  1996年   5篇
  1995年   5篇
  1994年   7篇
  1993年   4篇
  1992年   2篇
  1991年   2篇
  1990年   2篇
  1989年   1篇
  1988年   1篇
  1987年   4篇
  1986年   1篇
  1984年   3篇
  1981年   1篇
  1964年   1篇
排序方式: 共有961条查询结果,搜索用时 46 毫秒
61.
Inspired by attachment theory, the authors tested a series of theoretically derived predictions about connections between attachment working models (attachment to one's parents assessed by the Adult Attachment Interview; M. Main & R. Goldwyn, 1994) and the effectiveness of specific types of caregiving spontaneously displayed by dating partners during a stressful conflict-resolution discussion. Each partner first completed the Adult Attachment Interview. One week later, each couple was videotaped while they tried to resolve a current problem in their relationship. Trained observers then rated each interaction for the degree to which (a) emotional, instrumental, and physical caregiving behaviors were displayed; (b) care recipients appeared calmed by their partners' caregiving attempts; and (c) each partner appeared distressed during the discussion. Individuals who had more secure representations of their parents were rated as being more calmed if/when their partners provided greater emotional care, especially if they were rated as more distressed. Conversely, individuals who had more insecure (dismissive) representations of their parents reacted more favorably to instrumental caregiving behaviors from their partners, especially if they were more distressed. The broader theoretical implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
王建芳  夏清国 《计算机工程》2007,33(22):266-268
探讨一种基于可编程片上系统的嵌入式绞线式列车总线(WTB)网络控制节点机的研制方案。该方案采用FPGA作为核心器件,将Altera 的NisoII软核处理器与WTB控制逻辑集成在单片FPGA 内,取代了原来的工控节点机和控制部件相组成的方案。减小了产品的体积和重量,降低了硬件开发成本。该文给出了系统的总体设计方案,并分析了测试结果。  相似文献   
63.
Humans have a biological predisposition to form attachment to social partners, and they seem to form attachment even toward non-human and inanimate targets. Attachment styles influence not only interpersonal relationships, but interspecies and object attachment as well.We hypothesized that young people form attachment toward their mobile phone, and that people with higher attachment anxiety use the mobile phone more likely as a compensatory attachment target. We constructed a scale to observe people's attachment to their mobile and we assessed their interpersonal attachment style.In this exploratory study we found that young people readily develop attachment toward their phone: they seek the proximity of it and experience distress on separation. People's higher attachment anxiety predicted higher tendency to show attachment-like features regarding their mobile. Specifically, while the proximity of the phone proved to be equally important for people with different attachment styles, the constant contact with others through the phone was more important for anxiously attached people.We conclude that attachment to recently emerged artificial objects, like the mobile may be the result of cultural co-option of the attachment system. People with anxious attachment style may face challenges as the constant contact and validation the computer-mediated communication offers may deepen their dependence on others.  相似文献   
64.
谈永明  邵东亮 《化工机械》2011,38(4):457-460
以焦炭塔失效的敏感部位——筒体与裙座连接处附近区域为研究对象,采用大型有限元分析软件ANSYS,分析、比较了4种不同的连接形式(一般对焊型、搭接型、堆焊型和整体煅焊型)对机械应力强度的影响.结果表明,连接形式对最大机械应力的影响并不明显,从连接处的应力值来看,整体煅焊型和堆焊型结构明显比另外两种结构好,搭接型的应力值最...  相似文献   
65.
Genetic variation at a single nucleotide polymorphism (SNP) in the mu-opioid receptor gene (OPRM1) of both humans and rhesus macaques Macaca mulatta has been associated with differential affinity to the endogenous ligand beta-endorphin as well as alterations in pain sensitivity, drug and alcohol dependence, and social behaviors. The new study by Higham et al. (2011) presented in the current issue of this journal shows for the first time that some of the natural variation in maternal behavior observed in rhesus macaque populations can also be explained by genetic differences at this SNP. This work, in conjunction with other recent studies showing that genetic variability at this same locus are related to changes in infant attachment, provides unique insights into how opioids have been reutilized during evolution to coordinate the mother-infant relationship. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
66.
In a sample of 247 college students, the contributions of adult attachment orientations and several other boundary regulation variables to measures of self-splitting (i.e., the tendency to report diffuse and chaotic self-experiences) and other-splitting (i.e., the tendency to acknowledge unstable perceptions of and feelings toward one's friends) were explored. Adult attachment orientations and self-other boundary regulation variables, respectively, explained unique variance in each criterion measure. High levels of attachment anxiety and self-concealment and low levels of self-other differentiation contributed most prominently to self-splitting, whereas high attachment anxiety, low emotional reactivity, and high needs for social approval best predicted other-splitting. Implications of these findings for advancing a more delineated understanding of splitting tendencies are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
67.
This study used multinomial logistic regression to examine relationships between child-care experience (in the context of overall family functioning) and preschool attachment. Attachment behavior was assessed at 36 months with the Strange Situation, and A, B, C, and D attachment classifications were assigned using the MacArthur coding system. Maternal sensitivity was the strongest predictor of preschool attachment classification. With respect to child-care effects, as at 15 months, no child-care factors (quantity, quality, or type) predicted, in and of themselves, attachment security at 36 months. However, 1 of 3 interactions involving child care that were detected at 15 months reemerged at 36 months: When maternal sensitivity was low, more hours per week in care somewhat increased the risk of the insecure-ambivalent (C) classification. There was significant but modest stability of attachment classifications from 15 to 36 months, especially for children with A and C classifications. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
68.
69.
This paper reports results from measurements of the electron concentration in wakes behind aluminum spherical models flying at velocities of 2–5 km/sec in air-xenon mixtures at a total pressure in the ballistic track of 20–100 torr. The heating of the models moving in the ballistic track and aluminum ablation from their surfaces were calculated. The rate constant of electron attachment to microparticles is found, and it is shown that it depends on the fraction of xenon in the mixture. The dependence of the coefficient of electron accommodation to the microparticle surface on the xenon concentration in the mixture is obtained and explained from a physical point of view.__________Translated from Fizika Goreniya i Vzryva, Vol. 41, No. 3, pp. 65–73, May–June, 2005.  相似文献   
70.
针对立盘过滤机滤饼附液率较高的问题,主要从年心轴、分配头、扇形板及滤布选用等方面进行了深入探讨,分析了反吹风、进料分配器、滤液的排放方式等对立盘过滤机滤饼附液率的影响,提出了相应的改进措施。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号