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1.
目的:测定景东县野生茯苓、何首乌及草血竭中铅、镉、砷、汞的含量.方法:采用原子荧光光谱法测定4种重金属的含量.结果:景东县3种药材中4种重金属含量均≤0.2 mg/kg;各元素测定的线性关系良好,r=0.999 5~0.999 8;精密度测定RSD<5.0%(n=6),重复性试验RSD<5.0%(n=5),加样回收率在99.4%~103.0%.结论:景东县3种野生草药中的重金属含量均未超标.  相似文献   

2.
云南部分地区木香中重金属含量的测定   总被引:2,自引:0,他引:2  
目的:检测花甸坝药材场、银桥及中甸所产木香中镉、铅、砷、汞的含量.方法:采用原子荧光光谱法测定4种重金属含量.结果:3个地区木香中检测出的重金属镉≤0.011mg/kg、铅≤3.5mg/kg、砷≤0.11mg/kg、汞≤0.002 6mg/kg,含量均低于<药用植物及制剂进口绿色行业标准>限定值.各元素线性关系良好,r≥0.9993,回收率为99.10%~102.20%,RSD<5%(n=6).结论:花甸坝药材场种植的木香重金属(除铅外)的含量较另外两个地区的低.  相似文献   

3.
为建立沙棘PV粉、沙棘油中铅、砷、汞的原子荧光光谱检测方法,通过试验确定了样品前处理方法,对负高压、灯电流、载气、屏蔽气、原子化气高度、酸度等测试条件进行了优化。在优化的工作条件下,用原子荧光光谱法测定其中的铅、砷、汞的含量。结果表明:对所测元素铅、砷、汞,校准曲线的相关系数分别为:0.999 7、1.000 0、0.999 9;检出限分别为:0.000 1、0.000 2、0.000 02 mg/kg;相对标准偏差为1.2%~4.83%;用加标回收率评价方法的准确性,回收率为92%~105%。该方法快速、简便、准确且灵敏度高,为沙棘产品中重金属含量测定提供了较好的方法。  相似文献   

4.
建立了测定资丘木瓜药材中铜、铅和镉三种重金属含量的方法:采用火焰原子吸收光谱法检测铜的含量,以石墨炉原子吸收光谱法检测铅和镉的含量.3种重金属测定的检测限为0.0006μg/mL、0.0030ng/mL、0.0024ng/mL,相对标准偏差(RSD)为2.7%、2.9%、1.2%,回收率为100%105%,线性相关系数为0.999和0.992、0.995,均符合要求.经测定3批资丘木瓜药材中铜、铅、镉的含量分别为13.53105%,线性相关系数为0.999和0.992、0.995,均符合要求.经测定3批资丘木瓜药材中铜、铅、镉的含量分别为13.5316.24 mg/kg、0.016316.24 mg/kg、0.01630.0232 mg/kg、0.22670.0232 mg/kg、0.22670.3364 mg/kg,结果表明:3批木瓜样品中重金属的含量均符合《药用植物及制剂进出口绿色行业标准》中有关重金属标准的规定.  相似文献   

5.
氢化物发生原子荧光法测定土壤中铅镉砷3种有害重金属   总被引:2,自引:0,他引:2  
应用氢化物发生-原子荧光法对土壤中铅镉砷含量进行测定。研究了分析测定条件;测定铅、镉、砷的线性范围分别为:0~40μg/L,0~5μg/L,0~40μg/L;相关系数分别为:0.9999,0.9999,0.9994。应用于样品测定,测定结果的相对偏差小于2.6%;加标回收率为96.8%~104%。  相似文献   

6.
目的:对大理花甸药材场种植的附子、川芎、木香、三分三和大黄中砷、汞、镉、铅4种重金属元素的含量进行测定和分析。方法:采用原子荧光分光光度法,并对测定方法进行了方法学考察。结果:在最佳工作条件下对四种重金属元素进行测定,平均回收率在97.61%~102.18%,RSD在0.001%~1.04%。结果显示,五种药材中砷、汞、镉、铅4种重金属测定结果符合2005年版药典中重金属含量的限量标准。结论:该测定方法操作简便,快速,精密度及准确度高,适用于五种大宗药材中4种重金属含量的测定。  相似文献   

7.
为建立准确、快速地同时测定谷类产品中微量重金属元素含量的方法,采用电感耦合等离子体质谱法测定藜麦和绿豆芽等谷类产品中砷、镉、铅、锰、铜、锌和铁等7种微量重金属元素.以硝酸和双氧水消解样品,调谐优化仪器分析条件,锌、砷、铜、锰和铁等5种元素选用KED模式,铅和镉选用STD模式,以标准曲线法进行测定.结果显示:砷、镉、铅、锰、铜、锌和铁的线性回归方程分别为y=1.49×102x+0、y=3.06×102x+0、y=1.026 7×104x+0、y=1.029×103x+0、y=1.088×103x+0、y=2.67×102x+0和y=3.4×101x+0;砷、镉、铅、锰和铜的线性范围均为0.10~800.0μg·L-1,锌的线性范围为5.00~300.0μg·L-1,铁的线性范围为5.00~800.0μg·L-1,相关系数均在0.999 4~0.999 6之间;检出限在6....  相似文献   

8.
采用常规生化分析方法测定了20尾青海湖裸鲤肌肉营养成分,并首次对鱼肌肉中微量元素进行检测。结果显示:鱼肌肉中蛋白质含量为19.28%,脂肪为1.73%,灰分为1.25%,水分为78.38%。在测定的汞、砷、铜、锌、铅和镉6种微量元素中,汞的含量为0.123 4 mg/kg,砷为0.130 6 mg/kg,铜为0.255 mg/kg,锌为2.255 mg/kg,铅为3.485 mg/kg,镉为0.09 mg/kg。其中锌的含量超过国家食品规定标准将近7倍。  相似文献   

9.
目的:建立对基础干扰大的食品添加剂氢氧化钠中重金属的快速测定方法。方法:利用ICP-MS同时测定了食品添加剂氢氧化钠中砷、铅、镉、汞、铬五种重金属元素。结果:该方法完全克服了本体干扰大的缺点,五种元素标准曲线呈现良好的线性相关性,线性相关系数落在0.999 0~0.999 9的范围内;五种元素样品重复测定相对标准偏差(RSD)均小于3.7%,检出限在0.03~0.09 ug/L之间,加标回收率在91%~102%之间。结论:实现了对食品添加剂氢氧化钠中五种微量重金属元素准确快速分析。  相似文献   

10.
林小兵 《科学技术与工程》2024,24(16):6973-6979
为研究南方典型区域稻田土壤—水稻系统中重金属含量,系统采集了江西省进贤县、金溪县、渝水区、高安市、安福县和兴国县等6个水稻主产区典型田块土壤、水稻和灌溉水,重点分析了土壤和水稻铅、镉、砷和汞含量及其土壤养分,并采用单因子污染指数和内梅罗综合指数对土壤—水稻系统中重金属含量进行评价。结果表明,研究区稻田土壤pH、有机质、总氮、总磷、总钾、碱解氮、有效磷和速效钾总均值分别为5.48、32.99 g/kg、2.06 g/kg、0.54 g/kg、16.04 g/kg、156.71 mg/kg、14.00 mg/kg和94.98 mg/kg。研究区土壤铅、镉、砷和汞含量总均值分别为35.46、0.18、7.21和0.17 mg/kg,单因子污染指数均小于1,内梅罗综合污染指数为0.56,土壤环境质量等级为清洁;但渝水土壤镉含量为0.37 mg/kg,超过限量标准(0.30 mg/kg),土壤环境质量属于警戒状态。研究区糙米铅、镉、砷和汞的含量总均值分别为0.06、0.17、0.24和0.0086 mg/kg,单因子污染指数均小于1,内梅罗综合污染指数均值为0.77,糙米环境质量等级为警戒限;但兴国和渝水糙米镉含量分别为0.22和0.35mg/kg,均超过限量标准(0.20 mg/kg),环境质量等级分别为警戒限和轻度污染。相关性表明,糙米镉与土壤镉和铅呈显著正相关,而与土壤砷呈显著负相关;糙米砷与土壤砷和有效磷呈显著正相关。总之,重金属镉是调查区域水稻安全性最主要的潜在污染元素,需重点关注兴国和渝水两地水稻食品安全。  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.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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