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《世界有色金属》2021,(15)
目的:探究地质矿物金属元素含量测定过程中,影响不确定度增加的化学因素。方法:选择某矿山地质矿物作为实验样品,利用ICP-OES法对实验样品中三种不同金属元素含量进行测定,计算测定结果的不确定度,并在实验过程中对可能存在产生不确定度的化学因素进行分析。结果:通过实验结果得出,在对实验样品金属元素含量测定过程中,三种不同金属元素的含量不确定度分别为0.824μg/mL、0.264μg/mL和0.352μg/mL。产生不确定度的化学因素包括实验样品稀释、实验样品消煮、实验样品消煮液定容等。结论:在对地质矿物中金属元素含量测定时,被测定样品在消解前处理产生的不确定度最大。 相似文献
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利用新型多元素测定仪的良好线性,建立了硫氰酸盐光度法测定钨精矿中三氧化钨含量的方法。对试样的熔融条件、称样量、结果的计算方法、显色剂的配制等方面进行了优化,并用管理样和生产样品验证了分析方法的准确度和精密度。结果表明,试样用过氧化钠与碳酸钠混合熔剂熔融,熔块经EDTA(20 g/L)-乙醇(5 g/L)浸取液浸取后,铁、钙、锰、铜、镍、铋等对测定没有干扰,但铌干扰测定,可用草酸溶液消除。方法用于钨精矿中三氧化钨的测定,测定值与参考值或重量法测定值相吻合,相对标准偏差(RSD,n=6)在0.12%~0.30%之间。 相似文献
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《世界有色金属》2020,(10)
由于传统测量仪器在进行地质矿物中的金属元素测定工作,没有根据金属元素含量测量的工作曲线圈定异常数值范围,因此测定结果精准度低。针对这一问题,进行波长色散型的X射线荧光光谱仪测定地质矿物中的金属元素研究。通过对地质矿物样品进行检测,确定地质矿物中的背景值与异常下限。本文采用荷兰帕纳科公司制造Axios-mAX型波长色散型的X射线荧光光谱仪一次测定地质矿物样品中Cu、Pb、Zn、Sn、W元素含量,将电感耦合等离子体光谱仪(ICP-OES)与帕纳科波长色散型的X射线荧光光谱仪所测结果进行对比分析。实验结果表明,帕纳科波长色散型的X射线荧光光谱仪测定地质矿物样品中的金属元素含量更为准确,更加适合实际生产需要。 相似文献
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《中国钨业》2020,(1):72-76
采用硫氰酸盐分光光度法测定废催化剂中钨含量,存在样品难分解、流程复杂等问题。实验采用盐酸-硝酸-高氯酸混合酸分解样品,加入氢氧化钠使铁、锰、钒、镍、铜等元素形成沉淀,而钨以钨酸盐形式存在于溶液中以达到分离,用氯化亚锡-三氯化钛作还原剂,在盐酸介质中,将钨(Ⅵ)还原为钨(Ⅴ)与硫氰酸盐形成黄色的络合物,建立了硫氰酸盐分光光度法测定废催化剂中钨的分析方法。实验表明:钨的质量浓度在2.0~12.0μg/mL范围内与其对应的吸光度符合朗伯比尔定律,相关系数为0.999 8。将该实验方法用于测定4个废催化剂样品中钨含量,测定结果的相对标准偏差(RSD,n=7)在0.54%~1.99%之间。按照该实验方法测定4个废催化剂样品中钨,测定结果与电感耦合等离子体原子发射光谱法(ICP-AES)测定结果一致。 相似文献
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丁二酮肟光度法测定铜合金中的镍是一种常用的方法之一。然而用EDTA掩蔽铜时,参比溶液中的镍将缓慢显色,使吸光度不稳定。本法用配合力强于EDTA的CyDTA(或称1,2—二胺环己烷四乙酸)掩蔽铜,则参比溶液中镍的显色更加缓慢,吸光度稳定时间由用EDTA掩蔽铜的10min延长为本法的50min。本法尤其适于分析铜合金中低含量镍及成批大量样品。 相似文献
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由于传统地质矿物中多金属元素含量同时测定方法在实际应用中具有较高的检出限值,为此提出微波消解ICP-AES法同时测定地质矿物中的多种金属元素含量研究。首先利用微波消解技术对采集到的地质矿物样本进行微波消解处理,然后利用电感耦合等离子体发射光谱仪(ICP-AES)检测到处理后的地质矿物中多种金属元素电解质浓度,最后根据金属元素电解质浓度与金属元素含量的线性关系对地质矿物中多种金属元素含量进行计算分析,以此完成基于微波消解ICP-AES法的地质矿物中的多种金属元素含量同时测定。经实验证明,设计方法检出限值远远低于传统方法,更适用于地质矿物中多种金属元素含量同时测定。 相似文献
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人造白钨中三氧化钨的测定 总被引:3,自引:0,他引:3
建立了人造白钨中三氧化钨的测定方法。试样以盐酸溶解,在引入晶种技术的条件下,加入高氯酸-硝酸混合液,低温浓缩至冒白烟,析出钨酸,经过滤、洗涤、溶解、蒸干、灼烧、称量,计算三氧化钨量,用光度法测定滤液和残渣中三氧化钨量,补正结果。 相似文献
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The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed. 相似文献
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TA Solokhina LS Shevchenko IuV Se?ku EG Rytik LV Besedina TS Veshchugina 《Canadian Metallurgical Quarterly》1998,98(6):42-46
Usage of quality of life of psychiatric patients' relatives as the parameter of estimation of the quality of psychiatric care is considered. By means of standard questionnaire elaborated by the authors as well as by means of both individual and group conversations the quality of life was analyzed in 40 relatives which lived together with psychiatric patients. Different spheres of their life and difficulties (financial, social-psychologic, production) were examined in families with such patients. The defects of psychiatric care that had direct influence on the quality of life of the psychiatric patients' relatives are outlined. 相似文献
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Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies. 相似文献
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鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美". 相似文献
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针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。 相似文献