问题 问答题 论述题

溅渣护炉时,如何确定合理的留渣量?

答案

参考答案:

留渣量一方面要保证足够的渣量,在溅渣过程中使炉渣均匀地喷溅涂敷在整个炉衬表面,形成10~20mm厚的溅渣层;另一方面,随炉内流渣量的增加,熔渣可溅性增强,有利于快速溅渣。

合理的留渣量主要决定于以下因素:

(1)熔渣可溅性:根据熔池溅渣动力学研究,转炉上部溅渣主要依靠氮气流溅射护渣。渣量少,渣层过薄,气流易于穿透渣层,削弱气流对渣层的乳化和破碎作用,使反射气流中携带的液体滴数目减少,不利于转炉上部溅渣。

转炉留渣量过大,强化了转炉上部喷射溅渣的效果,往往造成炉口粘渣,炉膛变形。

(2)溅渣层的厚度与均匀性:渣量过少,溅渣层薄,上部不均匀,甚至溅不上渣。

(3)溅渣时间的长短:溅渣时间一般随溅渣量的增加而延长,但渣量过少,会使溅渣的效率降低。

(4)溅渣成本:留渣量过大,调渣剂的用量将会增加,使溅渣成本提高。

填空题

I ply agree with the contention that absence of choice is a rare circumstance, primarily because this contention accords with common sense and our everyday experience as human beings. Besides, the reverse claim-that we do not have free choice-serves to undermine the notions of moral accountability and human equality, which are critical to the survival of any democratic society.

41. The role of free will of humans in choice

Common sense dictates that humans have free will, and therefore the true absence of choice is very rare. The only possible exceptions would involve extreme and rare circumstances such as solitary imprisonment or a severe mental or physical deficiency—any of which might potentially strip a person of his or her ability to make conscious choices. Yet, even under these circumstances, a person still retains choices about voluntary bodily functions and movement. Thus, the complete absence of choice would seem to be possible only in a comatose state or in death.

42. The nature of absence of choice

People often claim that life’s circumstances leave them with "no choice." One might feel trapped in a job or a marriage. Under financial duress a person might claim that he or she has "no choice" but to declare bankruptcy, take a demeaning job, or even lie or steal to obtain money. The fundamental problem with these sorts of claims is that the claimants are only considering those choices that are not viable or attractive. That is, people in situations such as these have an infinite number of choices; it’s just that many of the choices are unappealing, even self-defeating.

43. Choice is beyond our control

Besides, the contention that we are almost invariably free to choose is far more appealing from a sociopolitical standpoint than the opposite claim. A complete tack of choice implies that every person’s fate is determined, and that we all lack free will. According to the philosophical school of "strict determinism," every event, including human actions and Choices, that occurs is physically necessary given the laws of nature and events that preceded that event or choice. In other words, the "choices" that seem part of the essence of our being are actually beyond our control.

44. The logical result of strict determinism and of the new "scientific determinism"

However, the logical result of strict determinism and of the new "scientific determinism" is that we are not morally accountable for our actions and choices, even those that harm other individuals or society. Moreover, throughout history monarchs and dictators have embraced determinism, at least ostensibly, to bolster their claim that certain individuals are preordained to assume positions of authority or to rise to the top levels of the socioeconomic infrastructure. Finally, the notion of scientific determinism opens the door for genetic engineering, which poses a potential threat to equality in socioeconomic opportunity, and could lead to the development of a so-called "master race." Admittedly, these disturbing implications neither prove nor disprove the determinists’ claims.

45. Insistence of tree will

I would concede that science might eventually disprove the very notion of free will. However, until that time I’ll trust my p intuition that free will is an essential part of our being as humans and, accordingly, that humans are responsible for their own choices and actions.

[A] For example, almost every person who claims to be trapped in a job is simply choosing to retain a certain measure of financial security. The choice to forego this security is always available, although it might carry unpleasant consequences.

[B] Our collective life experience is that we make choices and decisions every day on a continual basis.

[C] However, the dilemma seams to be unavoidable which gives people a lot of Painfully experience with it.

[D] In sum, despite the fact that we all experience occasional feelings of being trapped and having no choice, the statement is fundamentally correct.

[E] Recent advances in molecular biology and genetics lend some credence to the determinists’ position that as physical beings our actions are determined by physical forces beyond our control. New research suggests that these physical forces include our own individual genetic makeup.

[F] Assuming that neither free will nor determinism has been proven to be the correct position, the former is to be preferred by any humanist and in any democratic society.

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单项选择题 A1/A2型题