首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 140 毫秒
1.
目的 采用氰基柱分离,高效液相色谱法测定水产品中孔雀石绿.方法 采用氰基柱分离、流速为1.0 mL/min的等梯度洗脱方式,对其样品中孔雀石绿进行测定.结果 最低检测浓度LMG为0.02 ms/L,MG为0.5 mg/L.线性范围达0.1~160.0 mg/L,最低检测远远大于SC/T3021-2004线性范围(MG0.01~0.04 mg/L;LMG0.02~0.40 mg/L).而且,等梯度洗脱方式又扩大了液相色谱的应用范围.样品加标回收率65.8%~82%.结论 该方法简便、分离效果好、分析速度快、节省试剂、精密度高、灵敏、准确、线性范围宽.  相似文献   

2.
采用胶束电动色谱-质谱联用法同时测定心脑康胶囊中的芍药苷、葛根素、大黄素含量。该方法以未涂层石英毛细管(80cm×50μm)为分离通道,以30 mmol/L月桂酸-90 mmol/L氨水(pH值9.0)为缓冲溶液,50%异丙醇(含1 mmol/L乙酸)为鞘液,工作电压为25kV。测定结果:各组分在18 min内达到完全分离,芍药苷、葛根素、大黄素的线性范围分别为0.20~200mg/L、0.50~500mg/L、0.020~300 mg/L,检出限分别为0.020mg/L、0.050mg/L、0.0060 mg/L。样品的加标回收率在96.5%~102%之间,相对标准偏差均小于3.1%。该方法简便、快速、准确可靠,已成功应用于心脑康胶囊中芍药苷、葛根素、大黄素的含量测定。  相似文献   

3.
提出了一种反相高效液相色谱法同时测定4种苯二氮卓艹类药物的分析方法.考察了4种苯二氮卓艹类药物的保留值与流动相组成、流速、pH及柱温等色谱条件的关系,优化了色谱条件.确定了以ODSHypersil为色谱柱,甲醇-水(51∶49;V/V,用氨水调pH7.8)为流动相,流速为0.8mL/min,柱温为45℃,检测波长为220nm的最佳色谱条件.甲苯作为内标物,以内标法峰面积定量.硝西泮,地西泮,三唑仑和艾司唑仑线性范围分别是0.1mg/L~320mg/L,0.2mg/L~320mg/L,0.1mg/L~320mg/L和0.08mg/L~320mg/L;检测限分别为0.1mg/L,0.2mg/L,0.1mg/L和0.08mg/L.该方法用于尿液中的苯二氮卓艹类药物的测定.其回收率为97.0%~108.7%,标准偏差为1.7%~3.0%(n=7).该方法简单、快速、精确、灵敏、重复性好.  相似文献   

4.
该文研究了ICP-AES技术测定硒基物料中的镍钢铁铅碲.方法进行了仪器最佳分析条件、测量条件的选择、基体分离效果、共存元素干扰试验、精密度、加标回收和方法对比试验等研究.试验结果表明:硒经硫酸分离后,在30%的王水介质中,铅小于120 mg/L时,不影响镍钢铁碲的测定.在选定条件下镍铜铁铅碲加标回收率分别为96.8%~104.0%、100.0%~103.9%、98.5%~100.6%、97.0%~100.0%、95.0%~107.7%.RSD分别为4.33%、3.50%、7.52%、2.31%、4.75%.检出限分别为0.0070 mg/L、0.0032 mg/L、0.0021 mg/L、0.0079 mg/L、0.0093 mg/L.  相似文献   

5.
离子排斥色谱法测定酸奶中的有机酸   总被引:1,自引:0,他引:1  
采用离子排斥色谱法分离测定了酸奶中有机酸的含量,考察了流动相组成、流速、柱温对分离检测的影响.6种有机酸的检测限为3.7~24.4 mg/L,各组分回收率为90%~110%.主要存在的有机酸为柠檬酸和乳酸.  相似文献   

6.
毛细管气相色谱法测定盘香中烯丙菊酯和八氯二丙醚   总被引:2,自引:0,他引:2  
采用毛细管气相色谱法对盘香中烯丙菊酯和八氯二丙醚含量进行了分离测定,结果表明,烯丙菊酯和八氯二丙醚分别在0.01~4 g/L和0.03~3.60 g/L范围内线性关系良好,线性相关方程分别为y=3 068.7x+443 152.8和y=2 412.8x+100 704.9,线性相关系数r=0.999 7,0.999 6.每单盘盘香样品中烯丙菊酯和八氯二丙醚含量分别为22.5~34.7 mg,70.3~96.8 mg,平均回收率分别为95.2%~100.9%, 95.3%~101.7%.本方法快速,简便,分离效果好,准确度高,可用于生产企业和质检部门的质量监测.  相似文献   

7.
建立了以高效液相色谱分离制备玉米大斑病菌2号小种毒素的方法,研究了以Nova-PakC18分析柱、制备柱对检测波长、流动相、pH值对分离和制备的影响.结果表明5-羟甲基-2-呋喃甲醛的检测限为0.017 mg/L,其他组分的相对偏差为0.09%~1.9%.在0.005~0.10 g/L范围内,标准毒素的线性回归良好,相关系数和回收率分别为0.971 3和98.2%.该方法快速、准确且重现性好,适于毒素的分离制备.  相似文献   

8.
建立离子色谱法分离检测两种鲜果和干果中葡萄糖、果糖和蔗糖的分析方法.采用METROSEP CARB 1(150mm×4.0mm)阴离子交换分离柱和脉冲安培检测器,对淋洗分离条件进行优化.确定柱温为32℃、淋洗液为180.0mmol/L NaOH溶液,淋洗液流速为1.0mL/min,总分析时间8min.在1.0-40.0mg/L范围内葡萄糖、果糖和蔗糖分别呈良好线性.相关系数分别0.99996、0.99992、0.99991,检出限分别为0.126mg/L、1.072mg/L、0.085mg/L,精密度为0.31%~3.50%,回收率为92.23%~102.37%.该方法具有预处理简单,结果准确和快速有效等优点,可为鲜果和干果的检测提供一个简单有效的方法.  相似文献   

9.
采用三氟化硼-甲醇为衍生化试剂,以HP-FFAP毛细管柱为分离柱,建立了培氟沙星的气相色谱分析法.培氟沙星在质量浓度1.0 mg/L~250.0 mg/L内,药物与内标物峰面积比和药物浓度呈良好的线性关系,检出限为10 μg/L.该方法前处理步骤简单,处理后杂质干扰少,灵敏度高,适用性强,用于药物制剂和体液中培氟沙星含量的测定,平均回收率为93.75%~102.73%,日间RSD均小于2.85%(n=5).  相似文献   

10.
在pH值为1.0 的HCl溶液中,采用CL-磷酸三丁酯(TBP)萃淋树脂分离富集Cr(Ⅵ)和Cr(Ⅲ),并用对氨基-N,N-二乙基苯胺分光光度法测定了三价铬和六价铬的含量.实验结果表明,该法在最大吸收波长554 nm处的表观摩尔吸收系数为3.4×104 L·mol-1·cm-1,线性范围为0~1.6 mg/L,Cr(Ⅲ)和Cr(Ⅵ)的检测限分别为0.01 mg/L和0.007 mg/L;Cr(Ⅲ)和Cr(Ⅵ)质量浓度测定值分别为0.32 mg/L和0.57 mg/L时,其相对标准偏差分别为4.4%(n=6)和2.6%(n=6);Cr(Ⅲ)和Cr(Ⅵ)的标准加入回收率分别为90.0%~102.0%和97.5%~105.0%.该法可用于测定电镀废水中Cr(Ⅲ)和Cr(Ⅵ)的含量.  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.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
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   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号