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1.
单柱离子色谱法测定饮用水,井水和矿泉水中微量硫酸根   总被引:1,自引:0,他引:1  
本文研究了单柱离子色谱法测定饮用水、井水和矿泉水中微量硫酸根的方法。样品经适当稀释,微孔滤膜过滤即可直接进样分析。淋洗液最佳浓度为2.6mmol·L^-1H2C8H4O4/2.5mml·L^-1H2NC(CH2OH)3。电导检测器检测、检测灵敏度为1.6μs/cm。最低检出限为0.15μg/ml,线性范围1.0 ̄2.5×10^3μg/ml,相对标准偏差1.5%,平均回收率97.66 ̄98.77%。  相似文献   

2.
本文研究了铅溴络合物在高氯酸-磷酸-草酸介质中的极谱行为。确定底液组成为5%NaBr-11%HClO4-5%H3PO4-0.8%H2C2O4。工作曲线线性范围为0-150μg/50ml检测下限达0.01μg/ml体系选择性好,应用于实际样品的测定,获得满意结果。  相似文献   

3.
利用二-(2-乙基已基)磷酸(HDEHP)、异丙醚和乙醚溶剂萃取In(Ⅲ),并测定了In(Ⅲ)在有机相和水相之间的分配比.In(Ⅲ)在HDEHP-HNO_3、HDEHP-HClO_4和异丙醚-HBr体系中的化学产额依次为95.2%,91.7%和89.2%,在1mL的InCl_3医用放射性核素制剂中,Cu,Fe和Ag杂素元素的含量依次不大于0.04μg,0.15μg和2.1μg。  相似文献   

4.
单柱离子色谱法同时测定土壤中溴和碘的研究   总被引:3,自引:0,他引:3  
本文研究了以邻苯二甲酸/三羟甲基氨基甲烷为淋洗液的单柱离子色谱法同时测定土壤中微量溴和碘离子的方法。样品采用碳酸钠-氧化镁混合熔剂半熔,热水浸提,无基体干扰。淋洗液最佳浓度为2.2mmol.L^-1,H2C8H4O4/2.0mmol.L^-1H2NC(CH2OH)3。最低检测限Br^-0.065μg/ml.I^-0.027μg/ml。相对标准偏差Br^-,1.96%,I^-3.17%,回收率Br^  相似文献   

5.
反相高效液相色谱测定三羟甲基丙烷   总被引:1,自引:0,他引:1  
本文建立了一种用反相高效液相色谱测定三羟甲基丙烷的方法,选择CLC-C_8柱(150×6.0mm),流动相为CH_3CN∶H_2O(75∶25v/v),流速为每分钟0.6ml,柱温为室温等条件,三羟甲基丙烷的保留时间为4.8min,变异系数为Cv=1.2%,回收率为102%,具有快速、准确、操作简便的特点.  相似文献   

6.
利用二-(2-乙基已基)磷酸(HDEHP),异丙醚和乙醚溶剂萃取In(III),并测定了In(III)在有机相和水相之间的分配比。In(III)在HDEHP-HNO3,HDEHP-HClO4和异丙醚-HBr体系中的化学产额依次为95.2%,91.7%和89.2%。在1mL的InCl3医用放射性核素制剂中,Cu,Fe和Ag杂素元素的含量依次不大于0.04μg,0.15μg和2.1μg。  相似文献   

7.
石墨炉原子吸收光谱法测京万红中的镉   总被引:1,自引:0,他引:1  
本文研究了利用石墨炉原子吸收光谱法测定京万红中镉,以HNO3-HClO4-H2O2处理样品,转化为测定溶液,残留的HNO3、HClO4对测定无影响,可检测0.0024μg/g的镉;精密度2.4%;回收率在95-110%。  相似文献   

8.
探讨了1-硝基蒽醌(1-NO_2AQ)和1-氨基蒽醌(1-NH_2AQ)同时测定和分别测定的色谱条件,提出了在Shim-packCLSS-SIL色谱柱上,以正庚烷-1,4二氧六环-乙酸乙酯(65:35:5(V/V)为流动相,流量为1.5ml/min,柱温40℃,以分光光度检测器于254nm处检测时,4min内使1-NO_2AQ与1-NH_2AQ分离;5min使1-NH_2AQ与杂质分离;7min可使1-NO_2AQ与杂质分离的高效液相色谱分析法。其绝对检出下限1-NO_2AQ为0.012μg,1-NH_2AQ为0.026μg,变异系数分别为1.1%和0.96%,回收率分别为99.7%和100.2%。  相似文献   

9.
本文研究了利用石墨炉原子吸收光谱法测定京万红中镉.以HNO3-HClO4-H2O2处理样品,转化为测定溶液。残留的HNO3、HClO4对测定无影响。可检测0.0024μg/g的镉;精密度达2.4%;回收率在95-110%.  相似文献   

10.
AgNO_3和a-ph_2ppy,(a-(C_6H_5)_2P(NC_5H_5))在加有少量H_2O_2和NaOH的C_2H_5OH水溶液中反应生成标题化合物的灰黑色晶体。属四方晶系,空间群P4_1,a=1.300nm,C=4.076nm,v=6.884nm ̄3,Z=8,D_c=1.67gcm ̄(-3),R=0.059,r_ω=0.072.每一不对称单元中存在二套独立而结构基本相同的[Ag_2(a-ph_2PPy)_2] ̄2+,它的二个Ag原子和二个a-ph_2PPy中-N-C-P-桥的N,P原子联接成为一个稳定非共面八员环,而环内Ag,Ag间距分别是0.314,0.3l0(nm),均未成键。不对称单元中的二个八员环通过的O原子与环上Ag原子的弱成键而具有结构联系。环内还出现了罕见的三配位Ag原子。  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.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
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   

19.
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   

20.
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   

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