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1.
尿中O6-乙酰吗啡的膜式固相萃取及GC/MS/SIM测定   总被引:1,自引:0,他引:1  
建立尿中O6-乙酰吗啡的膜式固相萃取(disk SPE)以及GC/MS/SIM定量测定的方法.用SPEC.C18AR/MP3固相萃取柱萃取,以含2%(v/v)氨水的氯仿:丙醇(4:1)为洗脱液,对尿中的O6-乙酰吗啡进行提取.经BSTFA衍生化后再用GC/MS/SIM测定,O6-乙酰吗啡检出限可达0.004μg/mL;同一根萃取柱连续使用7次,没有出现堵塞和污染,回收率及RSD未见下降;用所建立的diskSPE方法对嫌疑尿样进行分析,与液-液萃取的结论一致.该方法适合于法医毒物分析.  相似文献   

2.
采用自制的固相微萃取涂层, 通过顶空固相微萃取与气相色谱法(HS SPME GC)联用测定水中的多环芳烃(PAHs)和酞酸酯(PAEs), 并优化了固相微
萃取条件. 实验结果表明: 当样品中加入4 g NaCl, 并以一定速度搅拌, 70 ℃顶空萃取50 min, 280 ℃解吸5 min时, 其检测限为0.005~0.1 μg/L, 线性范围为1~100 μg/L. 使用该方法检测武汉市东湖水样的加标回收率为72.0%~116.3%, 相对标准偏差(RSD)为5.2%~8.5%.  相似文献   

3.
高效液相色谱法测定果酒中的糖、甘油和乙醇   总被引:4,自引:0,他引:4  
 研究了高效液相色谱法测定果酒中的糖、甘油和乙醇的方法.果酒样品用Sep-Pak-C18固相微萃取小柱预分离,以WatersSugar-PakⅠ钙型阳离子交换柱为固定相,0.05g/LEDTA钙钠水溶液为流动相,示差折光仪为检测器,一次进样测定果酒样品中的蔗糖、葡萄糖、果糖、甘油和乙醇.最低检测限在微克级,相对标准偏差在0.92%~1.52%之间,标准回收率在97%~105%之间.方法用于果酒样品的测定,结果满意.  相似文献   

4.
SPE-UPLC-MS/MS快速测定豆制品中的乌洛托品   总被引:1,自引:0,他引:1  
建立了一种固相萃取-超高效液相色谱质谱联用(SPE-UPLC-MS/MS)测定豆制品中乌洛托品的分析方法。样品经粉碎后,采用乙腈提取,ProElut PXA小柱净化,Shim-pack XR-ODS色谱柱分离,在电喷雾正离子模式下用质谱仪进行MRM分析。结果表明:乌洛托品在0~160μg/kg范围内呈现良好的线性关系,线性相关系数为0.9998,该方法对应的检出限和定量限分别为0.3μg/kg和1μg/kg在5~100μg/kg添加水平下,乌洛托品回收率为88.4%~97.1%,相对标准偏差为5.39%~8.74%。该方法简便,快速,可成功应用于豆制品中乌洛托品的检测。  相似文献   

5.
为研究建立血中多巴胺的固相萃取/LC-MS/MS方法,采用OASIS○RWCX3cc(60mg)固相萃取柱进行提取,应用LC-MS/MS方法进行检测,运用保留时间和MRM方式来对血中多巴胺进行定性定量分析。在柠檬酸盐缓冲液pH=5时,SKF525A和多巴胺的固相萃取回收率分别达83.18%~114.63%,75.52%~93.01%;最低检测限(LOD)分别为0.05、0.1ng,线性范围0.005μg/mL~10μg/mL,相关系数分别为0.9998、0.9997。该方法回收率高,能快速准确地对血中多巴胺进行定量分析。  相似文献   

6.
用椰壳活性炭小柱对水样中的亚硝胺进行固相萃取,以SB-C8柱为分离柱,不同体积比的甲酸和甲醇为流动相进行梯度洗脱,采用大气压化学电离源和多重反应检测模式,建立了固相萃取(SPE)技术联合液相色谱-三重四级杆质谱(LC-TQMS)测定饮用水中8种亚硝胺消毒副产物的方法.考察上样时间、洗脱液量、氮吹时间和pH对回收率的影响,并优化固相萃取过程.结果表明,固相萃取过程中,上样时间1.5h,洗脱用量13mL,氮吹时间75min和pH 8时可以获得较高的回收率,8种N-亚硝胺类化合物在1~100μg·L~(-1)范围内线性关系良好,相关系数均大于0.99,8种N-亚硝胺类化合物的加标回收率为67.05%~93.78%,相对标准偏差为3.08%~9.23%(n=6),方法的检出限和仪器检出限分别为0.55~3.12μg·L~(-1)和0.12~1.95μg·L~(-1).  相似文献   

7.
DSPE-GC/MS快速检测葡萄酒中52种农药残留   总被引:1,自引:0,他引:1  
利用分散固相萃取GC-MS分析,建立了葡萄酒中52种不同极性农药残留的快速检测方法.葡萄酒样品用酸化乙腈经振荡提取和超声辅助提取后,上清液用混合吸附填料进行分散固相萃取净化,高速离心后,再通过氮吹方式浓缩,复溶,过滤膜,用GC/MS检测.与传统前处理方法相比,分散固相萃取技术在检测成本和处理速度上有很大优势.52种农药在3个浓度添加水平上的加标回收率范围是60%~110%,RSD15%(n=5),定量限是0.000 7~0.032 3 mg/kg.  相似文献   

8.
研究以超高效液相色谱—三重四级杆串联质谱联用技术(UPLC-MS/MS)测定陈皮中T-2毒素含量的方法.陈皮用乙腈-0.1%甲酸溶液提取,经PSA(乙二胺-N-丙基硅烷)净化,LCMS/MS电喷雾正离子多反应监测(MRM)模式检测.T-2毒素在1~25μg.L-1的浓度范围内进样量与峰面积呈良好的线性关系(r=0.9996),陈皮中T-2毒素的检测限为2.0μg.kg-1.平均加样回收均为91.86%,RSD为2.88%(n=9).该法操作简便,结果准确,可作为陈皮中T-2毒素残留量检测方法.  相似文献   

9.
阳春砂仁中总黄酮、异槲皮苷和槲皮苷含量测定研究   总被引:1,自引:0,他引:1  
建立阳春砂仁中异槲皮苷和槲皮苷含量的高效液相(HPLC)测定方法.异槲皮苷进样量在0.0183~0.0915 μg范围内有良好的线性关系,平均回收率为102.69%,相对标准偏差为0.70%(n=6);槲皮苷进样量在0.029 4~0.147 μg范围内线性关系良好,平均回收率为103.15%,相对标准偏差为0.68%(n=6).建立了紫外分光光度法测定砂仁中总黄酮含量的方法,采用槲皮苷为对照品,浓度在0~9.8 μg/mL.范围内线性关系良好,平均回收率为100.89%,相对标准偏差为1.19%(n=6).本方法简便快捷,可作为砂仁含量测定质量控制方法.  相似文献   

10.
建立了固相微萃取,气相色谱/质谱联用技术(SPME/GC/MS)测定水中壬基酚的新方法,并确定最佳实验条件。方法检测限为0.1μg/L;相对标准偏差4.07%。用此方法测定扎龙湿地水样,结果未检测出壬基酚。  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   

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