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1.
本文介绍了在pH=1.4的KCl-盐酸缓冲溶液中,以5-Br-PADAP为显色剂,用三阶导数分光光度法直接测定原油及渣油中微量铁的方法。本法不加掩蔽剂,利用导数分光光度法具有的抗干扰及高分辨的优点可以消除镍和钒的严重干扰。本法简单、灵敏、准确,在0~26μg/25ml范围内服从比耳定律。经对样品的多次测定和回收实验表明:本法标准偏差小于0.45ppm:相对标准偏差小于5%;回收率为99~109%,与等离子体法测定结果接近,符合测定要求。  相似文献   

2.
本文提出了以 5-Br-PADAP 做显色剂,在乙醇存在下,在pH=3.4的KHC_8H_4O_4-HCl缓冲溶液内,选择波长对:526nm(λ_2)-646nm(λ_1)(测镍)、620nm(λ_2)-674nm(λ_1)(测钒),用双波长分光光度法同时测定原油及渣油中微量镍、钒的新方法。本法灵敏度高、重复性好。镍、钒服从比耳定律的线性范围均在0~22μg/25ml,回收率在90~119%。经对多种油样的多次测定表明:本法的标准偏差<1.8ppm,相对标准偏差<10%。本测定结果与原子吸收光谱法、等离子体直读光谱法等分析方法的测定结果相符合。  相似文献   

3.
本文研究了金胶光度法测定铜、钴、镍盐中的微量砷。采用氢氧化镧作载体共沉淀砷,Cu~(2+)、Co~(2+)、Ni~(2+)在氨性介质中形成氨配离子被分离除去。砷用锌还原为AsH_3由酸性Au(SCN)_4~-溶液吸收,在保护剂存在下生成红色金溶胶,测量金胶溶液的吸光度便可测定砷。本法测砷,铜、钴、镍试液中含量在0~9μg范围内有良好线性关系.砷的最低检出量在硫酸铜、钴、镍盐中分别为0.36、0.40、0.70ppm。测定饲料微量元素添加物硫酸铜试样,十次测定的标准偏差为0.13,相对标准偏差为2.5%,七次测定的平均回收率大于95%。本法简易、决速、准确、灵敏。文献很少见有用简易光度法测定铜、钴、镍盐中微量砷的报导。  相似文献   

4.
本文介绍了一种用紫外四阶导数分光光度法直接测定炼厂污水中挥发酚的新方法。本法省去了萃取、蒸馏和比色等繁琐的预处理和测定步骤,采回水样可以直接测定,20分钟内可测出结果。本法灵敏、准确,测定结果与标准法十分吻合。本法的线性范围为0~32ppm;回收率在93%~108%之间;检出限为0.2ppm.  相似文献   

5.
在pH为3.0的邻苯二甲酸氢钾-盐酸缓冲溶液存在下,用5-Br-PADAP作显色剂,在水-乙醇介质中用高阶导数光度法同时测定了原油、渣油中微量镍、钒、铁。这种方法灵敏,选择性好,线性范围宽,省时。经过对不同产地的原油,渣油样品进行多次测定表明,这种方法的测定结果与原子吸收光谱法和等离子体直读光谱法的结果相吻合。相对标准偏差小于9%,回收率在90%~105%,符合测定要求。  相似文献   

6.
以5—Br—PADAP为显色剂,用二阶导数分光光度法对微量钴镍进行了同时测定,按“零交法”取569nm和616nm的峰——零导数峰值分别对镍钴定量,服从比耳定律的线性范围分别为0~14μg/25mL和0~22μg/25mL.样品的测定和回收实验表明,该方法准确、灵敏,符合测定要求,与原子吸收法的分析结果相吻合。  相似文献   

7.
用偏最小二乘法(PLS)的计算光度法同时测定了原油和渣油中的微量铁、镍、钒,对测定波长选择问题和抽象组分数的确定方法进行了研究。对模拟石油中铁、镍、钒含量制成的合成样进行了回收实验。结果表明,在铁、镍、钒加入量为0.4~10μg/25mL时,其回收率为94%~103%,优于用多元线性回归法的测定结果。  相似文献   

8.
荧光酮类试剂是灵敏度较高的一类金属显色剂,用于分光光度法测定微量金属元素已有报道.但以 BDMAF 作显色剂测微量镍未见报道,本文研究了 Ni 与 BDMAF 的显色反应,在碱性介质中,Ni 与 BDMAF 形成1:4的配合物,配合物可稳定10h 以上,实验结果表明,该体系的灵敏度高,选择性好,用本法可直接测定合金钢中的微量镍.1 实验部分1.1 仪器与试剂  相似文献   

9.
镍铁合金电镀液中微量钐的二阶导数分光光度法测定   总被引:4,自引:1,他引:3  
探讨了在弱酸性介质的钐-偶氮胂Ⅲ体系中采用二阶导数分光光度法测定微量钐的方法.本方法具有较好的选择性和灵敏度,检测限达0.250mg/L,铁、镍等共存离子的允许量可达千倍以上,故可以不经分离或掩蔽而直接测定镍铁合金镀液中的微量钐  相似文献   

10.
本文研究了在盐酸介质中、半二甲酚橙(SXO)——溴化十六烷基吡啶(CPB)分光光度法测定镍的适宜条件、络合物的组成及杂质干扰情况。制定了用分光光度法直接测定污水中微量镍的方法。该方法准确,灵敏度高,稳定性好,线性范围宽。  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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