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1.
在盐酸介质中,对硝基酚可以活化钒(V),催化氯酸钾氧化罗丹明6G 的反应,使其荧光猝灭.该方法的线性范围为5~50μg/L,检测限为2.5μg/L,回收率为96.5%,可直接用于污水中对硝基酚的测定.  相似文献   

2.
以丙酮溶液为溶剂,利用苯唑西林钠与对硝基酚发生荷移反应,建立了测定苯唑西林钠含量的一种新方法。苯唑西林钠与对硝基酚发生荷移反应后生成稳定的1∶1络合物,该络合物最大吸收波长为401.4 nm,线性范围10~80μg/mL,表观摩尔吸光系数ε=2.22×103L.mol-1.cm-1。苯唑西林钠回收率(质量分数)在98.35%~100.20%范围内,相对标准偏差≤2.71%。该方法简便、快速,可用于测定药物制剂中苯唑西林钠的含量。  相似文献   

3.
采用带有大气压化学电离离子源的超高效液相色谱-串联质谱仪,研究了水中2种典型硝基多环芳烃——1-硝基芘和1,8-二硝基芘的定量分析条件.结果表明,在多反应监测模式下,可直接分析水中痕量1-硝基芘和1,8-二硝基芘.其线性范围分别为0.72~12μg/L和0.48~48μg/L,相关系数分别为0.999 0和0.999 2,回收率分别为97.67%~104.44%和93.33%~103.13%,方法检出限分别为0.21μg/L和0.15μg/L,定量限分别为0.72μg/L和0.26μg/L.  相似文献   

4.
采用毛细管电泳安培检测法对厚朴酚及和厚朴酚的分离测定进行了详细研究.工作电极为0.3 mm碳圆盘电极,30 mmol/L、pH10.0的硼砂-氢氧化钠为运行缓冲液,分离电压21 kV,检测电位0.95 V.在最优化实验条件下,两待测物在6 min以内完全基线分离.厚朴酚及和厚朴酚的线性范围分别为0.2~50μg/mL和0.4~60μg/mL,检测限分别为0.06和0.2μg/mL.应用于中药厚朴以及中成药霍香正气水和保济丸中厚朴酚及和厚朴酚的检测.  相似文献   

5.
制备了一种十二烷基胍亚硫酸盐改性凹凸棒土的材料,利用红外、X射线衍射以及电镜对该材料结构进行了表征.将十二烷基胍盐改性凹土的材料用于处理含邻硝基酚的模拟废水,考察了吸附时间、pH值、邻硝基酚初始浓度以及改性凹土用量对吸附性能的影响.结果表明,在邻硝基酚初始质量浓度为100 mg/L、pH值为7、改性凹土用量为15 g/L、超声时间为40min时,邻硝基酚的去除率达到82.10%.  相似文献   

6.
建立了以Triton X-114为表面活性剂的浊点萃取-分光光度法同时测定厚朴酚与和厚朴酚含量的新方法,探讨了溶液的pH,Triton X-114浓度、平衡温度和平衡时间等因素对浊点萃取的影响.在最佳条件下,厚朴酚与和厚朴酚含量的线性方程分别为Y1=5.89×10-4x-1.14×10-3(相关系数为0.992 1),Y2=5.52×10-4x+7.71×10-5(相关系数为0.999 2);检测限分别为2.5μg/L和1.0μg/L.该方法成功用于药材中厚朴酚与和厚朴酚含量的测定,回收率为98.4%~104.3%.  相似文献   

7.
基于盐酸多巴酚丁胺对高锰酸钾氧化鲁米诺产生的化学发光的增强作用建立了一种测定盐酸多巴酚丁胺的新方法.在优化的实验条件下,测定盐酸多巴酚丁胺的线性范围为1 0×10-3~0 5μg/mL,检出限(3σ)为5 0×10-4μg/mL,对浓度为0 4μg/mL的盐酸多巴酚丁胺进行11次平行测定,其相对标准偏差(RSD)为3 39%.将本法用于注射液、血样以及尿样中盐酸多巴酚丁胺的测定,结果令人满意.  相似文献   

8.
基于山奈酚对Ce(Ⅳ)-罗丹明6G反应体系化学发光的增强作用,结合在线液膜萃取,建立了在线液膜萃取-流动注射化学发光法测定山奈酚的新方法.方法检出限为20.0μg/L,线性范围为5.0×10-5~1.0×10-2g/L.将该方法应用于尿液中山奈酚的测定,回收率为98.14%.  相似文献   

9.
不同产地牡丹皮中丹皮酚和芍药甙含量的HPLC法测定   总被引:5,自引:0,他引:5  
采用RP-HPLC方法建立了测定牡丹皮中丹皮酚和芍药甙含量的方法.色谱条件:C18色谱柱;丹皮酚测定所用流动相为甲醇—水(50∶50)为流动相,检测波长为274 nm,;芍药甙测定所用流动相为乙腈-0.1%磷酸溶液(18∶82)为流动相,检测波长为230 nm.结果:丹皮酚和芍药甙的线性范围分别为0.36-2.2μg/L和0.042-1.060μg/L,平均回收率分别为96.30%和98.21%,RSD分别为0.97%和0.64%.本方法简便、快捷、重现性好.用本方法对不同产地的牡丹皮中丹皮酚和芍药甙进行了测定,结果表明,牡丹皮中两种成分明显正相关,其中四川牡丹皮中两种成分含量最高.  相似文献   

10.
银杏外种皮杀虫活性成分研究   总被引:2,自引:0,他引:2  
采用活性追踪法从银杏外种皮中分离出杀虫活性成分银杏酚和白果酸.银杏酚对萝卜蚜的LD50为0.582 4μg/头,对小菜蛾3龄幼虫的LC50为2.0613g/L;白果酸对萝卜蚜的LD50为0.332 8 μg/头,对柑橘红蜘蛛、小菜蛾3龄幼虫的LC50分别为2.9110g/L、4.6002g/L.  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
<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   

19.
20.
<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has  相似文献   

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