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1.
将偏最小二乘紫外分光光度法应用于合成样品中四环素(TC)、土霉素(OTC)和甲稀土霉素(MTC)三组分含量的分析研究,确定了最佳实验条件.实验结果表明,偏最小二乘紫外分光光度法对样品中各组分的平均回收率在95.8%-103.6%之间,样品不经分离即可同时测定,取得了满意的分析结果.  相似文献   

2.
本文研究了偏最小二乘分光光度法同时测定多组分混合物的方法,探讨了偏最小二乘回归计算法有关参数对计算结果的影响.通过对三组分食用色素、四组分芳香醛模拟样和实际样品中食用色素含量的测定计算,结果表明偏最小二乘法计算结果稳定、精确度较高.  相似文献   

3.
分光光度法同时测定土壤中的铅、锌、镍、铜   总被引:1,自引:0,他引:1  
采用分光光度法进行土壤中铅、锌、镍、铜离子的同时测定研究,通过模拟蓄电池厂周围土壤情况探讨了同时测定的实验方法.用偏最小二乘(PLS)和径向基函数神经网络(RBFNN)方法解析测定数据,结果表明PLS法的预测准确性明显优于RBFNN方法.  相似文献   

4.
PLS萃取光度法同时测定贵金属元素Rh,Ir,Pd的研究   总被引:1,自引:0,他引:1  
本文采用偏最小二乘(PLS)萃取分光光度法,把富集和显色连为一体,运用Rh(Ir,Pd)-5-Br-PADAP体系,不加分离直接进行多组分的同时测定。  相似文献   

5.
用人工神经网络 紫外吸光光度法不经分离同时测定芴和苊 ,并与偏最小二乘 紫外吸光光度法比较 .对合成样品进行分析 .结果表明 ,人工神经网络法同偏最小二乘法一样能获得满意的分析结果  相似文献   

6.
用人工神经网络-紫外吸光光度法不经分离同时测定芴和苊,并与偏最小二乘-紫外吸光光度法比较.对合成样品进行分析.结果表明,人工神经网络法同偏最小二乘法一样能获得满意的分析结果.  相似文献   

7.
本文基于8-羟基喹啉络合显色反应结合偏最小二乘法提出了既灵敏又具较高选择性的多组分光光度测定方法。应用于铜、铅、镉、钴的同时测定,可不经分离,方法简便。  相似文献   

8.
痕量锗、钛和钼与邻苯二酚紫(PV)和溴化十六烷基三甲胺(CTMAB)在酸性介质中发生高灵敏的显色反应,所产生的三元络合物的吸收光谱严重重叠。用最小二乘法—分光光度法成功地测定了模拟样的上述3种痕量组分。结果表明,最小二乘法是化学计量学中一种可适用于较为复杂的痕量组分同时分光光度测定的优良的计算方法。  相似文献   

9.
偏最小二乘法用于荧光光度法同时测定磷,硅的研究   总被引:1,自引:0,他引:1  
将偏最小二乘法(PLS)用于荧光光度法同时测定磷、硅,对荧光光度法测定条件及PLS法最佳条件进行了试验和讨论。所建立的方法用于合金钢中磷、硅进行测定,获得了较满意的结果.  相似文献   

10.
研究了在4,5-二溴苯基荧光酮(DBPF)-CTMAB-OP显色体系中,用偏最小二乘法对痕量W、Mo、Zr进行同时分光光度测定.结果表明,它不仅保持了DBPF的高灵敏度,而且克服了三组份间的干扰,其测定的相对误差小于9%.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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