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1.
介绍了天钢1~#TRT顶压控制系统,对现有的顶压控制系统进行了分析,在原有差压调节模式的基础上增加了顶压调节模式,将实际操作改为差压调节与顶压调节两种互选模式,提高了系统的发电效率;对旁通阀组的控制进行了优化,优化后极大地提高了系统的安全性,保证了炉顶压力的稳定,延长了设备的使用寿命,产生了较高的经济效益。  相似文献   

2.
从转炉耐材的损害机理入手,分析了耐材的损耗机理,探讨了炉渣的优化机制,对炉渣的组成及渣料的使用进行优化,对溅渣的工艺进行了改进,实现了转炉护炉的提升,延长了转炉的使用寿命,降低了耐材的损耗,降低了转炉工序的成本。  相似文献   

3.
介绍了邯钢冷轧废水站的配套项目废水处理站的自动控制系统,主要从自控设备组成、网络控制系统等方面论述了控制功能的实现,该系统的应用为ERP的数据采集提供了很好的保证,提高了电气控制的集成度和可靠性,简化了控制环节,提高了生产效率.  相似文献   

4.
贺礼泰 《中国钨业》2003,18(4):15-19
概要介绍了樟东坑矿区的主要地质特征,在前人工作的基础上,对矿床的基本特征(尤其是矿脉的变化特征)进行了分析、探讨和总结;利用这些特性及其变化规律,采用一些新的探矿方法不但找到了一些隐伏盲矿,增加了地质储量,延长了矿山的服务年限,而且降低了探矿费用,减少了采矿的盲目性,节约了成本,增加了经济效益。  相似文献   

5.
为了解决大型制造企业数据中心架构变更后,在数据保护方面所面临的多种难题,对适用的数据保护技术进行了研究探讨.最终实现了企业数据保护平台架构的转型升级,提升了平台自身的安全性,改善了备份数据的传输架构,备份效率提升了10倍以上.实现了备份任务的集中智能管理,节约了备份窗口,实现了备份资源的一次性分配与自动回收,释放了备份...  相似文献   

6.
济钢中厚板厂3500线粗轧机改造主传动系统采用ACS6000SD变频驱动系统,系统的整流侧和逆变侧采用了对称结构,降低了维护难度;采用了IGCT技术,保证了系统的性能响应;使用了DTC技术,提高了系统的鲁棒性。这种交直交系统做到了对电网的最少谐波运行,既减少了对电网的污染,又省去了无功补偿系统的投资。  相似文献   

7.
根据鞍钢股份有限公司型钢生产线工艺实际,制定了机器人硬件设计方案和机器人软件实现方案,实现了工业机器人自动贴标喷码技术在型钢生产线的应用.该系统的应用满足了产线工艺要求,提升了产线生产效率,提高了产品标识的准确性和可追溯性,贴标准确率和喷码准确率均达到了99%,实现了危险岗位无人作业,作业周期缩短了25%;同时,实现了产品标识的统一规范性,提升了企业产品形象.  相似文献   

8.
孙普杰  赵宏 《有色冶金节能》2009,25(5):35-37,41
本文分析了影响空压机积炭堆积过快的原因,介绍了生产工艺中存在的问题及改进措施,改进后减少了空压机积炭堆积的速度,延长了空压机部件使用寿命,降低了维修成本,提高了空压机利用率和运行效率,达到节能降耗的目的。  相似文献   

9.
经过近20年的快速发展,我国镁挤压工业与技术获得了跨越式进步,不仅兴建了一批现代化的镁挤压企业,投产了一批3600t左右的现代化镁合金挤压机及其配套设备,而且开发了大批新技术、新工艺和新产品,大幅度降低了生产成本和提高了生产效率,拓展了应用领域,成为世界镁挤压大国。本文详细阐述了挤压成形在轻合金材料加工中的重要地位,指出热挤压成形是镁及镁合金材料最重要的加工方法,介绍了国内外镁挤压工业及技术的发展概况与趋势。  相似文献   

10.
原有泵池分矿箱旋塞提升机构操作困难,使用寿命短,研究设计并制作了新形式的旋塞提升机构。经过现场的安装试用,彻底解决了操作困难的现象,排除了故障缺陷,消除了操作时存在的安全隐患,保障了岗位操作人员的人身安全,减少了检修维护的工作量,降低了技术。  相似文献   

11.
Damage to the brain triggers a host of reactive responses in neurons and glia which are seen at sites of focal injury as well as at sites that are at a distance from the injury. Although many of these responses have been studied extensively, the signals that initiate the different responses have not been fully characterized, and it is still not understood how focal injury affects neurons and glia in distant sites. The present review summarizes recent findings that suggest that physiological events that occur at the time of the injury or during the early postlesion period can play an important and variable role in modulating neuronal and glial responses to injury. We focus on the events that occur in the hippocampal formation following unilateral lesions of the entorhinal cortex - a model system that has been used extensively for studies of cellular responses following focal brain injury. This lesion destroys the cells of origin of a massive excitatory projection to the dentate gyrus and hippocampus proper. Over time, the denervated neurons in the hippocampal formation are almost completely reinnervated as a result of local sprouting of systems that survive the lesion. Thus, this model system has been useful for studying cellular responses to both denervation and reinnervation. We summarize the information that this injury triggers physiological events that can strongly modulate gene expression in neurons and glia, including episodes of spreading depression that occur at the time of the injury, seizures that occur during the early postlesion period, the loss of afferent drive which leads to decreases in postsynaptic activity, and the restoration of activity that occurs in conjunction with reinnervation. We describe recent studies which suggest that some of these physiological events occur to a variable extent in different animals, especially the episodes of spreading depression and the recurrent seizures. Thus, the spatial pattern and temporal dynamics of altered gene expression following this "model" experimental injury may vary from animal to animal. The fact that physiological events strongly modulate the reactive changes in gene expression that occur following injury has important implications for understanding the sequelae of injury, and offers new opportunities for experimental and therapeutic interventions that may improve cellular repair, regeneration, and recovery of function.  相似文献   

12.
BACKGROUND: It has been hypothesized that the fact that both ribosomal RNA and the group I intron can bind to aminoglycoside antibiotics implies that these RNAs are evolutionarily related. This hypothesis requires the assumption that there are relatively few ways for RNA molecules to form aminoglycoside-binding sites. RESULTS: We have used in vitro selection to determine the diversity of aminoglycoside-binding sites that can be formed by RNA molecules. We have generated RNA 'lectins' that can bind aminoglycosides tightly and specifically. Sequence analysis indicates that there are many different ways to form tight and specific aminoglycoside binding sites. These artificially selected binding sites are functionally similar to those that have arisen from natural selection. CONCLUSIONS: Our results suggest that the presence of aminoglycoside-binding sites on RNA molecules may not be a useful trait for determining evolutionary relatedness. Instead, the fact that RNA molecules can bind these 'low molecular-weight effectors' may indicate that natural products such as aminoglycosides have evolved to exploit sequence- and structure-specific recognition of nucleic acids, in much the same way that lexitropsins have been designed by chemists to recognise specific nucleic acid sequences.  相似文献   

13.
The adult cuticular wing of Drosophila is covered by an array of distally pointing hairs that reveals the planar polarity of the wing. We report here that mutations in dachsous disrupt this regular pattern, and do so by affecting frizzled signaling. dachsous encodes a large membrane protein that contains many cadherin domains and dachsous mutations cause deformed body parts. We found that mutations in dachsous also result in a tissue polarity phenotype that at the cellular level is similar to frizzled, dishevelled and prickle, as many cells form a single hair of abnormal polarity. Although their cellular phenotype is similar to frizzled, dishevelled and prickle, dachsous mutant wings display a unique and distinctive abnormal hair polarity pattern including regions of reversed polarity. The development of this pattern requires the function of frizzled pathway genes suggesting that in a dachsous mutant the frizzled pathway is functioning - but in an abnormal way. Genetic experiments indicated that dachsous was not required for the intracellular transduction of the frizzled signal. However, we found that dachsous clones disrupted the polarity of neighboring wild-type cells suggesting the possibility that dachsous affected the intercellular signaling function of frizzled. Consistent with this hypothesis we found that frizzled clones in a dachsous mutant background displayed enhanced domineering non-autonomy, and that the anatomical direction of this domineering non-autonomy was altered in regions of dachsous wings that have abnormal hair polarity. The direction of this domineering nonautonomy was coincident with the direction of the abnormal hair polarity. We conclude that dachsous causes a tissue polarity phenotype because it alters the direction of frizzled signaling.  相似文献   

14.
Recently, from data obtained with a temporal order judgment (TOJ) task, Gibson and Egeth (1994) concluded that inhibition of return (IOR; a response time effect that reveals slower responding to targets at previously cued versus uncued locations) reflects impaired perceptual processing. By replotting their data, we demonstrate that the perception of temporal order is influenced only by the facilitatory effect of a cue at short stimulus onset asynchronies (SOAs) and is unaffected by IOR at long SOAs. The target paper proposed that, when extra stimuli are presented at task-relevant locations (i.e., in the TOJ task), IOR is prevented by a hypothetical process that is known as disinhibition of return (DOR). We argue that the assumptions that IOR affects perceptual processing and that DOR exists are unnecessary, as a more parsimonious response-based interpretation of IOR is consistent with their data. Further, we summarize recent results and present new data that demonstrate that DOR is unlikely.  相似文献   

15.
In this article, we show that feline predation involves a continuous gradient of activation between defense and attack and that predatory "play" results from an interaction of the two. Benzodiazepines (oxazepam, diazepam) escalated attack toward killing, so that cats that had avoided mice prior to the drug now played with them, cats that had originally played now killed, and cats that killed mice now did so with less preliminary contact. In such shifts, no sharp demarcation between play and predation was evident. Lateral hypothalamic lesions disrupted the escalation of attack. During recovery, attack was escalated once again along the gradient toward killing, but in the absence of both defense and play. A similar result was obtained in intact killers and nonkillers by the application of mild tailpinch. These results suggest that play with prey is a misnomer for predatory behavior that fails to escalate along the gradient between defense and attack. Movement notation analysis revealed that playful movements are adaptive in that they protect the cat from injury. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
The distinguishing features of professions, professionalization, and the institutionalization of expertise are discussed. Drawing on this discussion, a composite picture of a profession is developed. Using that composite picture, the question whether bioengineering is a profession is raised and answered affirmatively; the implications of that answer are explored. The institutional aspects and problems of contemporary professional practice receive special attention. It is argued that undertaking the task of constructing ethical structures of practice is itself an obligation of professional ethics. An approach that can be employed in that undertaking and, then, with one difference that is explained, used in making individual ethical decisions in one's capacity as a professional is suggested and defended. A key element in that defense is the fact that the approach squarely faces and successfully deals with what one writer calls the problems of knowledge and interest.  相似文献   

17.
Literature suggests that a complex and often hostile relationship exists between the science and practice of clinical psychology. Contributors to this conflict of viewpoints are reconsidered within the proposition that there are different roads to discovery and that there may be good reasons to keep the science and practice of clinical psychology somewhat separate. Results of a national survey of 325 psychologists are reviewed that support the view that psychological practitioners value research and consider their practices to be augmented by scientific findings. However, they are in need of vehicles of communication that will help them translate scientific findings into practice. Results suggest that practitioners do more to understand scientific findings than scientists do to understand the problems that face clinical practitioners. Ways to facilitate communication between and among these groups are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
How do children know the sentence “the glass is empty and not empty” is inconsistent? One possibility is that they are sensitive to the formal structure of the sentences and know that a proposition and its negation cannot be jointly true. Alternatively, they could represent the 2 state of affairs referred to and realize that these are incommensurate, that is, that a glass cannot simultaneously be empty and contain something. In 2 studies, the authors investigated how children (N = 186; ages 4–8) acquire competence to notice inconsistencies. The authors found that children could determine that 2 states of affairs were incommensurate before being able to determine that statements of the form p and not-p were inconsistent. The results demonstrate that competence in understanding inconsistent relations depends on (a) the ability to represent 2 states of affairs and (b) the ability to process negation in the context of an inconsistency. The authors discuss these results in relation to sources of competence that may underlie the assessment of such simple inconsistencies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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