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通过对沙钢铁钢界面铁水包多功能化技术的铁水出准率、铁水包周转系数、铁水温降、尾包等生产数据的 分析,研究了目前沙钢铁水包多功能化技术的运行特点和效果,讨论了铁水温降速率、铁水包保温性能、铁水包烘 烤、尾包管理等概念性问题,提出了提高铁水包多功能化技术运行水平的途径,以体现该技术更加明显的优势。 相似文献
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成分是钢铁制造流程铁钢界面物质流运行的关键参数之一,目前钢铁企业普遍存在炼铁和炼钢工序测得的铁水成分存在差异的问题,并由此导致脱硫站脱硫剂消耗量大、处理周期长、生产成本高。针对首钢京唐铁钢界面“一包到底”技术应用过程中铁水成分存在差异的问题,结合实际生产数据,统计了铁水成分差异的现状,并从生产工艺、检测方法等方面分析了差异形成的原因。结果表明,高炉与脱硫站测得的铁水Si含量绝对偏差平均为0.06%,S含量绝对偏差平均为0.024%,炼铁测得的铁水成分对脱硫和炼钢的参考性有限;铁水包装入多个铁次的铁水、高炉出铁过程铁水取样方法不科学、铁水转运过程部分元素与空气发生氧化反应及个别铁水样品中夹杂有炉渣,是造成铁钢界面铁水成分差异的主要原因。指出,钢铁企业应通过优化高炉出铁操作制度、改进铁水取样方法、加强铁水包管理、加强取样探头质量管理和建设沿途铁水快速取样装置等措施,解决铁钢界面铁水成分差异问题。 相似文献
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为研究铁水冲罐法对铁水预处理脱磷效果的影响,向放有一定量苏打的铁水罐中倒入铁水进行铁水脱磷工业试验研究。考察了铁水中Si、Ti浓度、铁水温度以及苏打添加量对脱磷率的影响,并比较了钙系脱磷剂与苏打的脱磷效果。结果表明:铁水中低的硅、钛浓度、低温以及适当的苏打消耗量有助于脱磷;与钙系脱磷剂只有一定的脱磷能力相比,苏打有较强的脱磷和脱硫能力;同时考察了氧气对苏打脱磷效果的影响,向铁水表面喷吹氧气可以减少铁水温降,为铁水的二次预处理提供温降空间,采用苏打铁水二次脱磷后,得到了w[P]<0.010%的铁水;还考察了苏打脱磷过程中w[Cr]、w[V]和w[C]的变化,铁水中铬浓度几乎不变,钒几乎全部被氧化进入渣中,而碳浓度大约减小了0.2%(质量分数,下同)。 相似文献
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通过钼丝炉上1kg铁水和感应炉上10kg铁水的实验,研究了铁水预处理时炉渣碱度和铁水温度对脱钛硅锰的影响,并系统的分析了其脱出规律.研究表明铁水中钛硅的氧化基本不受铁水温度和炉渣碱度的影响,锰的氧化受铁水温度和炉渣碱度的影响较大,低温、低碱度有利于铁水脱锰.当铁水温度T=1280℃,碱度R=0.44,铁水中钛硅锰可分别脱除至[Si]=0.011%,[Ti]<0.005%,[Mn]=0.024%,满足了高纯生铁对锰的指标要求. 相似文献
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火焰原子吸收光谱法测定合金结构钢中铬、锰 总被引:1,自引:0,他引:1
利用火焰原子吸收光谱法测定合金结构钢中铬、锰,此方法快速、准确、灵敏度高、精密性好,方法简便,并充分反应了现代仪器的高科技分析手段。合金结构钢使用较为广泛,因此利用原于吸收光谱法测定铬、锰,能迅速有效的达到检测目地的需要。本方法改变了以往化学法操作时间长、步骤多、消耗试剂多的弊病,解决了高氯酸氧化铬对人体的危害及对环境的严重污染。通过对各项做条件试验,优选了最佳仪器测试条件。对干扰元素铁、镍抑制铬的吸收,采用硫酸钠做干扰消除剂,彻底消除了干扰,测定数据稳定可靠。经过对标准样品的测定,重复性好,误差小,回收率达到99~102%,效果令人满意。 相似文献
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Connectedness to school, teachers, and family are all significant protective factors in adolescents' lives, yet the measurement of each varies considerably. This article describes the measurement properties of three composite scales of adolescent connectedness, adapted from the Add Health study and the California Healthy Kids Survey. These composite scales are created by either summing or taking the mean of all individual items, measured on an ordinal scale. This approach fails to account for the ordinal, non-normal nature of the data. Using a covariance approach, this article describes the measurement properties of the latent constructs of connectedness to school, teachers, and family and the contribution of each of the items used to compile the relevant composite score. The outcomes of this study will provide researchers and practitioners with information about the validity, reliability, and overall usefulness of each of the measures of adolescents' perception of their connectedness to school, teachers, and family. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Ignacio Fernández Olmo Emilio Chacón Angel Irabien 《Canadian Metallurgical Quarterly》2003,129(6):532-538
This paper reports the study of the leaching behavior of cement/metal oxides mixtures containing lead, chromium (III) and zinc oxides. A fractional factorial design of experiments (24?1) was carried out considering four factors, the concentration of ZnO, Cr2O3, PbO, and Fe2O3 in the formulations. Iron oxide was also included in the experimental design as it is usually the main constituent of industrial wastes from thermal processes, where lead, chromium and zinc oxides are also found. After 56 days of curing, samples were subjected to the Acid Neutralization Capacity Test and the concentrations of Cr, Zn, and Pb were determined in the leachate at different pH after filtering. The output variables for the analysis of the experimental data were the concentration of metals at initial pH (in water), at pH 9, 7, and 4, and the acid neutralization capacity of the samples at pH 9. The analysis of the results indicates that the immobilization of Zn and Pb in Portland cement is poor; these metals behave as their amphoteric hydroxides. However, the leaching of Cr (III) is in the range found in the control sample, indicating that the stabilization of Cr (III) is successful. 相似文献
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Within inshore or fluvial environments, submerged fine matter mud banks are characterized by a high water content, a great spatial variability, and a strong deformability. The study of their instabilities induced by the variation of hydraulic stress requires a coupled modeling of sliding, erosion, and deposition mechanisms. In order to predict the impact of dam reservoir emptying on the stability of immersed upstream slopes, the method of approach to the problem proposed here combines theoretical developments, numerical modeling, site observations, and measurements. First, the theoretically achieved sliding criterion is compared with unstable mud height measurements. For more accuracy in the representation of the natural events, the sliding criterion is then integrated within a numerical code which couples the computation of hydrodynamic conditions, the erosion, and deposition of mud and the banks sliding. Finally, the results of the combination of all these mechanisms are compared with the variations in the bathymetric profiles obtained on the experimental site. 相似文献
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为了阐明银含量对方铅矿浮选的影响,提高含银方铅矿中伴生银的综合回收效率,通过全面梳理前人研究成果,对含银方铅矿的资源状况、工艺流程和药剂制度进行了总结。首先,从不同维度和层面(从试验到模拟、从宏观到微观)综述了银含量对方铅矿的影响,其中包括银含量对方铅矿浮选行为及表面接触角的影响。然后,评述了前人利用红外光谱、微热动力学、电化学和量子化学等分析方法开展的有关银含量对方铅矿浮选行为影响机理的研究进展,上述分析方法相互验证,均证实银矿物对方铅矿的浮选有促进作用,且银含量与促进程度呈正相关。最后,针对含银方铅矿今后研究方向和银铅锌矿资源开发,提出科学、合理的建议,如:在现场生产中应尽量避免使用石灰调浆,如必须使用时,应控制好石灰用量,从而减少伴生银的损失。 相似文献
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For counseling settings, research suggests that softness, personalization, and order might affect the experience and the perceived expertness, trustworthiness, and social attractiveness of the therapist. This article discusses exploratory studies on college students' perception of the counseling office environment and whether the likely client experience was associated with the softness/personalization and order of the office. As stimuli, the studies used 30 color photographs of psychotherapists' offices viewed from the client's perspective. After obtaining ratings of the characteristics of each office, we obtained ratings from different groups of students of the quality of care and comfort expected in each office (Study 1) and how qualified, bold, and friendly the therapist in the office would be (Study 2). Additional studies examined the likelihood of choosing a therapist based on the office, and the first thought or feeling that came to mind about the office, the therapist, and the patient experience. There were strong correlations in response between groups (by whether they had experienced therapy; their level in school; their gender; and their major, location, and school size). The quality of care, comfort, therapist boldness, qualifications of the therapist, and the likelihood that one would choose a therapist based on the office improved with increases in the office's softness/personalization and order. Friendliness improved with increases in softness/personalization. The office choices, open-ended responses, and reported reasons for the ratings confirmed the importance of softness (comfort) and order. Research should test longer term exposure and behavior. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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利用电感耦合等离子体原子发射光谱法(ICP-AES)测定高纯钼样品中杂质元素含量时,由于钼元素具有丰富的谱线,因此钼基体对待测元素干扰较大。为了消除钼基体对待测元素的干扰,实验使用过氧化氢溶解样品,过量硝酸沉淀分离钼基体作为样品前处理步骤,建立了基体分离-电感耦合等离子体原子发射光谱法测定高纯钼中钙、铬、铜、钴、镁、镍、锌、镉和锰的方法。使用4mL过氧化氢溶解样品,10mL硝酸沉淀钼基体,钼的沉淀效率大于99%,沉淀后,各待测元素背景等效浓度均有下降,且回收率都高于85%,随沉淀损失较少。使用高纯钼基体沉淀分离的方法配制校准曲线,各待测元素校准曲线线性相关系数均大于0.999 7;方法中各元素的定量限为0.20~2.03μg/g。实验方法用于测定高纯钼样品中钙、铬、铜、钴、镁、镍、锌、镉和锰,结果的相对标准偏差(RSD,n=5)为2.0%~4.8%,测定结果与电感耦合等离子体质谱法(ICP-MS)结果一致。 相似文献
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Larochelle Serge; Lapalme Guy; Laurier Daniel; Peretz Isabelle; Polguère Alain 《Canadian Metallurgical Quarterly》1999,53(2):194
Reviews the book, Vocabulaire de sciences cognitives by O. Houdé, D. Kayser, O. Koenig, J. Proust, and F. Rastier (1998). The Vocabulaire de sciences cognitives contains 130 alphabetically ordered entries, each entry corresponding to a different word or expression used in cognitive science. The entries are treated from the point of view of each of the five main disciplines contributing to cognitive science: artificial intelligence, neuroscience, linguistics, philosophy, and psychology. The texts concerning a given entry form distinct sections labeled with the name of the discipline concerned. Numerous cross-references to related entries are given. Overall, the Vocabulaire contains about 200 different texts, a third of which have been authored by the members of the editorial board, each of whom is specialized in one of the disciplines mentioned; the remaining texts were written by 54 other authors from these various fields. Of the 130 entries, only 2 very pivotal terms in cognitive science (FUNCTION and REPRESENTATION) receive complete multidisciplinary treatment; 15 entries referring mostly to major cognitive functions (e.g., LANGUAGE, LEARNING, MEMORY, PERCEPTION, REASONING) are covered by three or four disciplines, and 31 others receive a bidisciplinary treatment. Analysis of the 144 pairs of disciplines found in these 48 entries shows the neighborhood among disciplines to be fairly evenly distributed except in the case of psychology and neuroscience, whose greater conceptual proximity is explained by the fact that most neuroscience texts have been written by neuropsychologists. The contributions of the various disciplines were reviewed by one specialist and by at least one nonspecialist. Although predictably more critical, the specialists did not identify many serious problems or errors. However, the reviewers expressed some reservations concerning the choice of the terms deemed worth of an entry, the limited number of disciplines contributing to some entries, the variable length and nature of the texts, as well as the exaggerated place sometimes given to secondary research. If the Vocabulaire de sciences cognitives does not constitute a monumental achievement, it is nonetheless an impressive piece of work, especially considering the breadth and state of the domain. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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为探究高炉喷吹兰炭的最佳配比,使用TG-DTG热分析技术研究了百善无烟煤、神华烟煤和兰炭组成混煤的燃烧特性。结果表明,混煤中兰炭配比量增加可以降低煤粉的着火温度与燃尽温度,缩短燃烧时间,提高综合燃烧特性指数,改善混煤燃烧性;升温速率增大,混煤反应速率峰值升高,综合燃烧特性指数升高,混煤燃烧性得到优化。使用KAS等转化率法分析了不同混煤方案的燃烧过程动力学,当兰炭配比量由0增加至40%时,活化能分别为115.25、113.03、112.22、108.20 和104.53 kJ/mol,兰炭的加入可以降低混煤的表观活化能。 相似文献
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Reviews the books The art of being, by Erich Fromm (1992); Basic writings, by Martin Heidegger (1993); History of the concept of time: Prolegomena, by Martin Heidegger (1992); Complexity: Life at the edge of chaos, by Roger Lewin (1992); The future of an illusion: Film, feminism, and psychoanalysis, by Constance Penley (1989); Human inquiry: A sourcebook of new paradigm research, by Peter Reason and John Rowan (1990); Reading Heidegger: Commemorations, edited by John Sallis (1993); and Truth and existence, by Jean-Paul Sartre (1992). Brief synopses of each book are presented, rather than full reviews. In The art of being, Fromm presents his synthesis of spiritual teachings from Zen to existentialism, as well as a synopsis of his earlier critiques of consumer capitalism. Basic writings is a collection of essays, lectures, and sections from Heidegger's major works. Of special interest to psychologists interested in Heidegger's methodology is the re-translation of the introduction to Being and Time. In History of the concept of time: Prolegomena, Heidegger elaborates the methodological and foundational connection of his work to Brentano, Dilthey, and Husserl, thus providing for the first time an authoritative understanding of the relationship of his uniquely hermeneutic phenomenology to the ideas of his predecessors. In Complexity: Life a the edge of chaos, Roger Lewin discusses the search for the set of rules that underly complexity theory and the "grand unification" of the life sciences. The future of an illusion: Film, feminism, and psychoanalysis, by Constance Penley, is a collection of essays on the sexual politics of representation. In Human inquiry: A sourcebook of new paradigm research, Reason and Rowan cover the philosophy, methodology, practice, and prospects of what the editors call "new paradigm research": alternative approaches to human science research that are both collaborative and experiential. Reading Heidegger: Commemorations is a richly provocative book of essays by an impressive list of 23 Heidegger scholars around the world. This text celebrates, reconsiders, and sometimes pokes fun at one of the most controversial and most important thinkers of our century. Finally, written in response to Heidegger's The essence of truth, Jean-Paul Sartre's Truth and existence provides a bridge between Sartre's Being and nothingness and his Critique of dialectical reason. It is a philosophical as well as psychological study of epistemology, based on his phenomenological ontology, that becomes a work on morality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献