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1.
铝敏化紫外分光光度法测定氧氟沙星   总被引:3,自引:0,他引:3  
研究了金属离子对氧氟沙星紫外光谱的影响及反应条件.结果表明,在pH 3.5~4.9的N aA c-HA c缓冲溶液中,铝离子对氧氟沙星吸光度有显著增敏作用.A l-OFLX体系的测定波长mλax=292 nm,线性范围为0.2~38.7μg/mL;回归方程为Y=0.0069 0.09438C(C=μg/mL),r=0.9998;检出限为3.5×10-2μg/mL.据此建立了测定药物制剂中氧氟沙星含量的铝敏化紫外分光光度法.方法灵敏、操作简便,用于药物制剂中氧氟沙星的分析测定,回收率在95%~105%之间,结果令人满意.  相似文献   

2.
流动注射化学发光抑制法测定痕量亚硝酸根的研究   总被引:4,自引:0,他引:4  
基于在碱性介质中,亚硝酸根对Lum inol-K3Fe(CN)6 体系发光反应具有强烈的抑制作用,建立了化学发光抑制快速测定痕量亚硝酸根的方法.测定NO2- 线性范围为1.0×10- 8 ~1.0×10- 6 g/m L,D.L= 5.6×10- 9 g/m L;对 4.0×10- 8g/m LNO-2 连续11 次测定的相对标准偏差为2.5% .  相似文献   

3.
在酸性条件下,甲磺酸培氟沙星分子中氮原子被质子化后与阴离子AuCl-4形成离子缔合物,该缔合物被二氯甲烷带入鲁米诺的氯化十六烷基三甲基铵(CTAC)反胶束溶液中,离解出来的AuCl-4立即与鲁米诺产生化学发光.在一定浓度范围内,发光强度与甲磺酸培氟沙星的含量成线性关系,从而间接测定甲磺酸培氟沙星的含量.在优化的试验条件下,线性范围为 0.001~10×10-6 g·mL- 1,检出限(3σ)为 0.02×10-9 g·mL-1,对浓度为1.0×10-6 g·mL-1 的甲磺酸培氟沙星进行11次平行测定,RSD为2.4%.该法已成功用于片剂、注射液和生物体液中甲磺酸培氟沙星的测定.  相似文献   

4.
当LuminolH2 O2 Ni2 混合溶液的化学发光 (CL)强度降至稳定基线值后 ,加入碱土金属离子 ,其化学发光强度再次显著增强 .基于此 ,结合低压离子色谱 (LPIC)分离技术 ,建立起Ca2 离子的LPIC CL分离检测新方法 .该方法的线性范围为 8 0× 10 -8~ 6 4× 10 -6g·mL-1,相关系数r=0 9998,检出限为 5 4× 10 -8g·mL-1,相对标准偏差为 1 33% (n =11) .测定牛奶中的Ca2 离子 ,并与原子吸收光度法对照 ,结果令人满意  相似文献   

5.
浊点萃取-荧光光度法测定废水中痕量铝   总被引:1,自引:0,他引:1  
建立了荧光光度法测定水中痕量铝离子的浊点萃取分离富集新体系.在pH=5.6的HAc-NaAc缓冲体系中,水样中的铝与8-羟基喹啉生成疏水性络合物.通过95 ℃水浴加热1.5 h,8-羟基喹啉-铝络合物被萃取到乳化剂(OP)表面活性剂相并与水相分开.在激发波长365 nm和发射波长510 nm下进行荧光测定,测定铝的线性范围为10.00~250.00 μg/L,方法的检出限(3σ)为0.39 μg/L,相对标准偏差(RSD)为3.6%,该法用于各种水样中痕量铝的测定,加标回收率为96%~105%,结果令人满意.  相似文献   

6.
根据AI 3 对KIO4氧化次甲基蓝褪色的催化行为,建立了测定痕量铝的催化动力学分析法,本法线性测定范围为0~720μg/L,检测限为1.1×10-8g/L,除Fe 3 外其余离子不影响测定,Fe 3 的干扰可用铜铁试剂-氯仿溶液萃取除去,利用本法测定水样中的铝含量,结果满意.  相似文献   

7.
兔子和小鼠不同组织苹果酸脱氢酶活性的研究   总被引:7,自引:0,他引:7  
本文采用苹果酸脱氢酶(M DH)催化过程中辅酶Ⅰ氧化还原型转化的特征,测定了兔子和小鼠不同组织M DH的比活力和米氏常数(km),比活力在370~1 055单位/m g蛋白之间,km范围为3.57~6.49×1-0 5m o l/L.快速老化小鼠病理模型的km增大10倍,为1.49~5.64×10-4m o l/L.  相似文献   

8.
基于二溴对甲基偶氮甲磺与钡离子的显色反应 ,建立了间接光度法测定硫酸根 .在硫酸根的样品溶液中加入已知过量的钡 ,沉淀硫酸根后对钡离子进行测定 .工作波长为 6 32 nm ,εmax=6 .5 9× 10 4 L· mol- 1 · cm- 1 ,线性范围为 0~ 2 5μg/2 5 m L .考察了常见离子的干扰情况 ,提供了一种新的测定硫酸根的光度法 ,用于测定水中硫酸根含量 ,相对标准偏差小于 2 % ,加标回收率为 97%~ 10 6 %  相似文献   

9.
以L i4S iO4为母体,煤矸石为原料,经高温固相反应制得L i8A l1-xS i2xP1-xO8系统的锂快离子导体.X射线衍射分析结果表明在0.5相似文献   

10.
基于在甲酸存在下 ,叶酸与高锰酸钾在酸性介质中的直接化学发光反应 ,建立了测定叶酸的流动注射化学发光新方法 .该方法测定叶酸的线性范围为 5.0×1 0 - 8~ 5.0× 1 0 - 6g/mL ,检出限为 1 .4× 1 0 - 8g/mL ,相对标准偏差为 3 .2 % (5.0×1 0 - 7g/mL叶酸 ,n =1 1 ) .该方法已应用于叶酸片剂中叶酸含量的测定  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.
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   

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 discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
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   

16.
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   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
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   

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