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1.
氟罗沙星在胶束体系中的荧光特性研究及应用   总被引:3,自引:0,他引:3  
目的:研究氟罗沙星在胶束体系中的荧光特性及应用.方法:用日立F-3010型荧光分光光度计测定,测定波长eλx=290 nm,eλm=450 nm,测定时最佳pH值范围为4.5~5.5.在表面活性剂十二烷基硫酸钠(SDS)存在下,由于胶束的生成,使氟罗沙星(FLRX)自身荧光大大增强,据此建立了在SDS胶束体系中测定氟罗沙星的新方法.结果:氟罗沙星浓度在0~0.9μg/mL范围内与荧光强度呈线性关系,相关系数0.9991,检测限为0.01μg.mL-1.加标回收率为97.1%~102.5%,相对标准偏差为1.5%~3.6%.结论:该方法简便,快速,可直接用于药物制剂中氟罗沙星含量的测定.  相似文献   

2.
研究了显色剂2-(5-羧基-1,3,4-三氮唑偶氮)-5-二乙氨基苯胺(简称CTZAN)与铁的显色反应.结果表明,在pH 6.0的HAc-NaAc缓冲体系中,CTZAN与Fe(Ⅲ)形成一种稳定的络合比为2:1的紫红色络合物,最大吸收波长位于570 nm处,络合物的表观摩尔吸光系数为2.08×104 L·mol-1·cm-1,Fe(Ⅲ)质量浓度在(0.08~0.8)μg/ mL范围内符合比尔定律.所拟方法不经分离直接测定纯铝和铝合金样品中微量的铁,测定结果与认定值相符.  相似文献   

3.
研究了氟罗沙星(FLRX)在胶束体系中的荧光性质,发现在酸性介质中十二烷基硫酸钠(SDS)对氟罗沙星有较强的增敏作用,据此建立了胶束增敏荧光光谱法测定氟罗沙星的新方法。在0.11μg·mL-1~5.5μg·mL-1范围内,FLRX的浓度与荧光强度呈良好的线性关系,检出限为0.07μg·mL-1。经加样回收实验,回收率为97.4%~107.2%,相对标准偏差为2.0%~4.6%。  相似文献   

4.
研究了新显色剂2-(5-羧基-1,3,4-三氮唑偶氮)-5-二乙氨基苯甲酸(简称CTZDBA)与铁的显色反应。结果表明,在pH4.0的HAc-NaAc缓冲溶液中,CTZDBA与Fe(Ⅲ)形成稳定的络合比为2∶1的紫红色络合物,最大吸收波长为560nm,络合物的表观摩尔吸光系数为2.21×104L.mol-1.cm-1,Fe(Ⅲ)质量浓度在(0~0.8)mg/L范围内符合比尔定律。所拟方法不经分离直接测定纯铝和铝合金样品中微量的铁,测定结果与认定值相符。  相似文献   

5.
在pH 3.50酸性介质中,Cu(Ⅱ)和Fe(Ⅲ)在非离子表面活性剂Tween-80存在下与5-Br-PADAP生成有色配合物.有色配合物最大吸收波长都位于570 nm处;表观摩尔吸光系数分别为7.96×104 L·mol-1·cm-1和6.30×104 L·mol-1·cm-1;Cu(Ⅱ)在0~13 μg/25ml,Fe(Ⅲ)在0~18 μg/25ml范围内符合比耳定律.用拟定的方法测定了铝片和水样中的Cu(Ⅱ)和Fe(Ⅲ),结果令人满意.  相似文献   

6.
在pH值为10.3的NH3H2O NH4Cl介质中,Fe(Ⅲ)与邻氯苯基荧光酮(以下简称o CPF)生成络合物,于-0.72V(vs.SCE)出现一灵敏的极谱波.铁(Ⅲ)含量在1.0×10-8~1.3×10-6mol/L范围内与峰高呈线性关系,检出限为4.0×10-9mol/L.用多种电化学方法研究了极谱波的性质及电极反应机理,证明-0.72V处的极谱波为络合吸附波,峰电流由中心离子Fe(Ⅲ)还原产生,络合物组成为Fe(Ⅲ)∶o CPF=1∶2,表观稳定常数K稳=5.4×1012.试验了30多种离子对峰电流的影响,并将该体系用于头发中痕量铁的测定.  相似文献   

7.
目的: 对氟罗沙星和培氟沙星贯序治疗下呼吸道感染进行药物经济学分析, 为临床提供用药参考. 方法采用回顾性研究法, 收集122例下呼吸道感染患者, 分成两个治疗组:氟罗沙星组和培氟沙星组, 采用统计研究和成本-效果分析方法对两治疗组进行药物经济学比较. 结果氟罗沙星和培氟沙星贯序治疗下呼吸道感染总有效率分别为89.83%和87.30%, 效果无显著差异(P>0. 05);治疗成本分别为290.63元和236.07元, 成本-效果比分别为3.23和2.70. 结论与氟罗沙星相比, 培氟沙星贯序治疗下呼吸道感染具有成本-效果优势.  相似文献   

8.
荧光法研究氟罗沙星与牛血清白蛋白的相互作用   总被引:13,自引:1,他引:12  
用荧光法研究了氟罗沙星对血清白蛋白的荧光猝灭现象,根据荧光猝灭双倒数图读物计算了氟罗沙星与牛血清白蛋白之间的结合常数,根据Foester能量传递原理计算出氟罗沙星在牛血清白蛋白上的结合位置,并根据热力学参数研究了氟罗沙星与牛血清白蛋白之间的作用力类型。  相似文献   

9.
分光光度法测定头孢曲松钠的含量   总被引:4,自引:0,他引:4  
通过研究头孢曲松钠与Fe3 的反应并确定其反应的最佳条件,从而建立新的分光光度测定法。头孢曲松钠与Fe3 在常温下能够立即形成稳定的络合物,该络合物在470nm处有最大吸收,表观摩尔吸光系数为1.5×103L/(mol·cm),线性范围为0.05~0.60mg/L.用该法测定头孢曲松钠药品,结果与中国药典法基本吻合,相对标准偏差为0.63%,回收率为99.2%~99.5%.  相似文献   

10.
2-(2-喹啉偶氮)-1,5-苯二酚光度法测定烟草中铁的研究   总被引:1,自引:0,他引:1  
合成了新试剂2-(2-喹啉偶氮)-1,5-苯二酚(QADHB),研究了2-(2-喹啉偶氮)-1,5-苯二酚与铁(Ⅲ)的显色反应在pH=7.0的HAC-NaAC缓冲溶液介质中,十六烷基三甲基溴化胺(CTMAB)存在下,QADHB与Fe(Ⅲ)形成红褐色稳定2∶1络合物,λmax=580nm,ε=2.37×104L.mol-1.cm-1.Fe3+含量在0~20μg/25mL内符号比尔定理,方法用于烟草中铁含量的测定,结果令人满意.  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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