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1.
钟勇  姜睛 《株冶科技》1998,26(4):45-47
基于HNO2介质中MnO2·xH2O能分离富集锑继而利用Sb(Ⅲ)与KI的铬阴离子[SbI4]^-在1.1 ̄1.8mol/L的H2SO4介质中与偶氮类显色剂5-Br-PADAP形成的离子缔合物,在乳化剂OP存在下,有较高灵敏度与选择性,可不经萃取分离水相光度法测定Cu中锑。线性范围0 ̄40μg/25mL,ε610=4.3×10^4。  相似文献   

2.
刘静  张华山 《冶金分析》1996,16(5):10-11,14
研究了新显色剂3,5-二溴0-4-氨基苯基荧光酮(DBAPF)与锰(Ⅱ)的显色反应,在阳离子表面活性剂溴化十六烷基三甲铵(CTMAB)存在下,PH9.0NH3.H2O-NH4Cl介质中,DBAPF与Mn(Ⅱ)形成1:2红色络合物,最大吸收小575nm表观摩尔吸光系数ε=1.0510^5,锰(Ⅱ)的浓度在0-8.5μg/25ml的范围内符合比尔定律。,拟定方法用于钢铁样品中微量锰的测定,结果满意。  相似文献   

3.
在弱碱性介质中,CTMAB微乳液存在下,5-(3-苯甲酸偶氮)-8-氨基喹啉(CPAQ)与钯(Ⅱ)生成3:1蓝色络合物,λmax=625nm,ε=9.40×104。钯的含量在0-20μg/25mL内符合比尔定律。方法用于钯催化剂中钯的测定,结果满意。  相似文献   

4.
在H_3PO_4介质中,有吐温-20和Mn(Ⅱ)存在下,4-氯苯基二安替比林甲烷(DApCM)与V(V)生成橙黄色产物,其λmax为485nm,ε=5.05×10~5L·mol~(-1)·cm~(-1)。钒量在0.5~3.5μg/25mL符合比尔定律。该法具有较高的灵敏度和较好的选择性,用于低合金钢样中微量钒的测定,结果满意。  相似文献   

5.
2,4-二氯苯基荧光酮分光光度法测定微量钨   总被引:4,自引:0,他引:4  
研究了2,4-二氯苯基荧光酮(DCPF)在表面活性剂CTMAB存在下与钨形成三元胶束络合物的反应条件.在强酸性介质中生成W(Ⅵ):DClPF=1:2的络合物,其最大吸收峰在522nm波长处,表现摩尔吸光系数ε为1.35×10 ̄5L·mol ̄(-1)·cm ̄(-1)、钨含量在0~10μg/25ml范围内符合比尔定律,大多数常见的阳离子不干扰钨的测定,拟定方法用于合金钢中微量钨的测定,结果满意。  相似文献   

6.
研究了新显色剂二溴甲基偶氮羧胂(DBMCA)与铈组稀土的显色反应。在0.16—0.60mol/L的盐酸介质中,铈组稀土与试剂形成蓝色的络合物,络合物的最大吸收峰在630nm处,摩尔吸光系数ε_(630)(La-Tb)为1.16×10~5-1.30×10~5。铈在0.5—12μg/25ml符合比尔定律。由于乙醇和表面活性剂TritonX-100的存在,方法具有良好的选择性,40mgCa~(2+),10mgFe~(3+),3mgTi~(4+)不干扰测定。本方法可以不经分离直接测炉渣和焊条皮中的铈组稀土.回收率  相似文献   

7.
合成了新试剂N-辛基-N’-(氨基对苯磺酸钠)硫脲(OPT),经过红外、紫外和元素分析等测试,确定了其组成和结构.并研究测定了试剂与40多种常见离子的反应及其络合物的表观摩尔吸光系数.表明它可作为Cu~2+ (m=0.015μg, c=0.50μg/mL), Au~3+(m=0.30μg, c=10μg/mL)的新鉴定试剂和光度法测定 Cu~2+(ε_301.4=1.82 X 10~5和 An~3+(ε_302.0=1.33 X 10~5的新显色剂.方法的灵敏度高,选择性好,操作简便.将该法应用于矿石样品  相似文献   

8.
本文提出了测定痕量铟的新方法,研究了在含氧有机溶剂及氯化十六烷基吡啶(CPC)存在下,2-[(5-溴-2-吡啶)偶氮]-5-二甲氨基苯酚(5-Br-DMPAP)与铟的显色反应条件。在pH6.5乙酸-乙酸钠缓冲体系中,铟与5-Br-DMPAP形成稳定的红色配合物,其波长为560nm,表观摩尔吸光系数为8.61×10 ̄4,线性范围0~60μg/25ml铟符合比尔定律,对多种常见共有离子的影响进行了研究,经巯基棉富集分高,用于岩石中铟的测定,结果满意。  相似文献   

9.
研究了新显色剂3,5—二溴—4—氨基苯基荧光酮(DBAPF)与锰(Ⅱ)的显色反应。在阳离子表面活性剂溴化十六烷基三甲铵(CTMAB)存在下,pH9.0NH3·H2O-NH4Cl介质中,DBAPF与Mn(Ⅱ)形成1∶2红色络合物,最大吸收波长575nm,表现摩尔吸光系数ε=1.05×105,猛(Ⅱ)的浓度在0-8.5μg/25ml范围内符合比尔定律,拟定方法用于钢铁样品中微量锰的测定,结果满意。  相似文献   

10.
介绍了用新显色剂二溴对氯偶氮甲磺(DBCMSA)光度法测定锶的方法,在 1.2mol/L H_2SO_4介质中,试剂与锶形成稳定的蓝色络合物,最大吸收波长为637nm,表观摩尔吸光系数ε=7.26X10~4,锶含量在0—25μg/25mL范围内符合比尔定律,应用于铝合金中锶的测定,获得满意结果.  相似文献   

11.
12.
根据深云立交桥梁的检测结果,对该桥目前的整体状况、工作状态,及其使用情况做出综合评价,对桥的病害原因进行了分析,并提出合理的加固方案。  相似文献   

13.
劳伦斯小说《儿子与情人》一个鲜明的语言特色就是标准英语和当地方言频繁的语码转换。莫瑞尔用方言来对抗妻子,而妻子坚持用标准英语,偶尔也用方言来讽刺、挖苦丈夫。语码转换反映了劳伦斯男女二元对立的哲学思想。  相似文献   

14.
摘要:在第4次工业革命浪潮的推动下,钢铁科学与技术正在经历数字化、智能化转型。钢铁行业全流程各工序均为“黑箱”,为多场、多相、多变的巨系统,具有复杂相关关系和遗传效应等。这些不确定性带来了巨大的挑战。挑战和机遇并存。这些不确定性提供了智能化和数字化技术的应用场景资源;钢铁行业极为丰富的大数据提供了挖掘其中蕴含客观规律的数据资源;现代的数据科学、智能技术为解决不确定性问题提供了强大的手段。以数据为中心,以工业互联网为载体,以实验工具、数字数据、计算工具为支撑,建设钢铁企业材料创新基础设施,将可以大幅度提高研发效率,降低研发成本,有力地支撑钢铁材料科学与技术的转型发展。实验工具平台除了传统的实验室仪器装备和中试装备之外,实际生产线被作为主要的实验工具。这些实验工具提供丰富、精准、写实的历史数据和现实生产数据,特别是生产线装备提供实际生产大数据,蕴含着生产过程中的全部规律,是极宝贵的数据资源。利用机器学习、深度学习等现代数据挖掘技术为计算工具,对这些数据资源进行处理、分析、计算,将数据转换为高保真度模型,可以得到具有“原位分析能力”的数字孪生。在工业互联网的总体架构下,以数字孪生为核心,组成信息物理系统,构建起基于数据自动流动的状态感知、实时分析、科学决策、精准执行的闭环赋能体系,解决生产制造、应用服务过程中的复杂性和不确定性问题,提高资源配置效率,实现资源优化,对材料行业转型发展提供关键技术支撑。虚实映射、实时交互、精准控制的信息物理系统与材料创新基础设施合二为一,以材料创新基础设施为基盘,形成具有“原位分析能力”的数字孪生,建设钢铁生产全流程、一体化的信息物理系统,必将推进钢铁行业智能制造蓬勃开展和数字化、智能化转型。  相似文献   

15.
Social comparison involves positioning the self relative to others on a vertical or status dimension (ranging from upward to downward comparisons) and a horizontal or solidarity dimension (ranging from contrastive to connective comparisons). Across 3 studies in which 389 undergraduates recorded everyday social comparisons (n = 4,417), downward and connective comparisons were rated as more helpful and mood enhancing than upward and contrastive comparisons. The effects of horizontal comparisons were greater for people for whom solidarity was an important value; however, the effects of vertical comparisons were not greater for people who valued status. The roles of the comparison target, topic, and situation were also explored; for example, noticing undesirable features of the target enhanced status but undermined solidarity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
Daniel Robinson suggests that much of the civil and criminal law "serves as the institutionalized form of praise and blame". Indeed it does. Pulling at this thread of Robinson's tapestry leads the reader straightaway to a host of truths about how law and morality not only intersect, but work together in harmony. "[L]aw", Robinson says, is a "vivid expression of deeper and impenetrably complex moral theories". This essay explores several of these harmonies, but focuses on two. One is that political society must be seen as the cooperation of free persons according to law, which persons hold common moral understandings. The second has to do with retribution as the moral justifying aim of punishing criminals. The author goes beyond Robinson's limited praise of retribution, and shows that some central features of our practice of punishment are understandable only within the retributive framework. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
Two studies investigated the role of expressive vocal behavior (specifically, speech rate and loudness) in fear and anxiety and in sadness and depression. In the 1st study, participants spoke about personally experienced fear and anxiety-arousing and neutral events using 3 different voice styles: fast and loud, normal, and slow and soft. In the 2nd study, participants spoke about personally experienced sad or depressing and neutral events using the same 3 voice styles. In both studies, the participants' highest levels of subjective affective and cardiovascular (CV) arousal occurred when they spoke about the emotional events in a mood-congruent voice style: fast and loud in the case of fear and anxiety, and slow and soft in the case of sadness or depression. Mood-incongruent voice styles canceled the heightened levels of CV arousal normally associated with these negative emotions. The voice-style manipulation had no significant effect on the participants' levels of CV arousal during the neutral discussions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
为解决单个企业的信息化投资风险、从整体上降低企业信息化投入,针对大邱庄钢铁产业的类型特点,设计了一种新型信息化公共服务平台。详细阐述了钢铁产品展示及交易平台的建设内容及系统开发技术。该平台集产品展示、信息查询、用户管理功能于一体,实现了全自动、全智能的在线管理和维护,适用于中小型企业。该平台的应用最大化地发挥了大邱庄的产业优势,对大邱庄工业园区的宣传和市场开拓起到了一定的作用。  相似文献   

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20.
The relationship between aging and negative affect is dynamic and complex. Although prior studies have often cited lower prevalence rates of anxiety and mood disorders among older individuals, these studies may miss the dynamic relationship between symptoms and aging. To evaluate a nonlinear model of the relationship between aging and negative affect, the author examined measures of neuroticism, anxiety, and depression symptoms in a cross-sectional, community sample (N = 335), ages 18 to 93. Results indicated a curvilinear relationship, with mean symptom levels increasing during early adulthood (until the mid-30s) and then showing a small decline until older adulthood (the mid-70s), when symptoms again increase with age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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