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1.
在聚乙烯酸(PVA)存在下,铋与钨酸盐反应形成铋钨杂多酸络阴离子,继而与罗丹明B(RB)形成离子缔合物。离子缔合物的最大吸收波长位于560nm,服从比耳定律范围为1.0~30μg/25ml,表观摩尔吸光系数ε值为7.32×107L·mol-1cm-1.体系至少稳定20天。考察了30多种共存离子的影响,大多数常见离子不干扰。探讨了IR光谱,饿钨杂多酸络阴离子具有Keggin结构。测定铋的适宜条件为CH2SO4=0.96mol/L,Cwo42-=1.82×10-4mol/L,CRB=4.18×10-5mol/L和PVA0.08%,本法已用于天然水、降水、钦用水及粗铅中铋的测定,结果与推荐值吻合,回收率满意。  相似文献   

2.
本文建立了铋(Ⅲ)-邻苯二酚紫-抗坏血酸(Bi(Ⅲ)-PV-AA)体系在单扫示波极谱仪上测定微量铋的方法.以5.0mol/L KOH为支持电解质,该体系有一灵敏导数极谱波.峰电位为-0.79V(vs.SCE).峰电流与铋的浓度在5.0×10~(-8)~1.1×10~(-6)mol/L成正比.应用循环伏安、脉冲极谱等方法确证了该极谱波属于络合吸附波.确定了吸附型体的络合比为Bi(Ⅲ):PV:AA=1:1:1.对其电极反应做了初步推测.  相似文献   

3.
合成了新试剂2-[3-(5-硝基苯并异噻唑)偶氮]-β-萘酚.并研究了试剂与铋的显色反应条件.用元素分析、波谱等鉴定其结构并测定其离解常数,结果表明,在pH=7.46时,试剂与铋发生灵敏的显色反应,形成稳定红色配合物,λmax=540nm,络合比Bi3+:R=1:2,摩尔吸光系数为5.13×104L·mol-1·cm-1.Bi3+在0~1.8mg·L-1范围内遵守比耳定律.  相似文献   

4.
研究了亚硝基R盐在汞电极上的电化学行为和电极反应机理.结果表明亚硝基R盐在汞电极上的电极反应为准可逆过程,电子转移数为4,其被还原为其相应的氨类化合物;吸附符合福兰克林吸附方程,吸附系数β=3.63×105 L/mol,饱和吸附量Γs=1.00×10-10 mol/cm2,吸附因子υ=0.94.  相似文献   

5.
在聚乙烯醇的存在下,当pH值为5.5~6.5时,Co(皿)—亚硝基R盐—乙基紫在水溶液中可形成稳定的三元缔合物。其λ_(max)=524nm,表观摩尔吸光系数ε为2.30×10~5L/mol·cm。钴(Ⅲ)含量在0~0.2μg/mL范围内吸光度遵从比尔定律,反应具有较高的灵敏度与选择性。方法用于合成样品中钴(Ⅲ)的测之,结果满意。  相似文献   

6.
在过量溴化钾存在的稀磷酸介质中 ,乙基紫的共振瑞利散射十分微弱 ,但是当乙基紫与配阴离子 [I2 Br]-反应 ,形成离子缔合物时 ,共振瑞利散射显著增强并出现一个新的共振瑞利散射光谱 .其共振瑞利散射峰位于 5 3 5nm和 3 3 5nm .研究了该反应的适宜条件和影响因素 .碘的浓度范围在 0~ 0 64μg/mL时 ,共振瑞利散射强度与碘的浓度成正比 .该方法具有较高的灵敏度 ,碘离子的检出限为 1 5 8ng/mL .该法具有较好的选择性 ,可用于痕量碘离子的测定 .  相似文献   

7.
研究了2-(4-氯-2-膦酸基苯偶氮)-7-(2,4-二氯苯偶氮)-1,8-二羟基-3,6-萘二磺酸(DC-CPA)与铋的显色反应.在0.06 mol/L HNO3介质中,铋与显色剂生成1∶2的蓝色配合物,最大吸收波长在691 nm处,该反应灵敏度高,6ε91=1.1×105L.mol-1.cm-1,B i(Ⅲ)含量在0.02~1.4 mg/L范围内符合比耳定律.应用该法测定了铜合金中微量铋,方法简便易行,结果满意.  相似文献   

8.
巯基棉分离富集光度法测定垃圾渗滤液中镉的含量   总被引:1,自引:0,他引:1  
在酸性条件下,甲基紫(MV)-亚硝基R盐(NRS)与Cd(Ⅱ)发生显色反应生成具有正、负吸收峰的紫色三元络合物.其最大吸收波长位于634(正吸收)和566 nm(负吸收),线性范围为0~2.65(正吸收)和0~2.90μg.mL-1(负吸收),表观摩尔吸光系数ε为1.13×104(正吸收)和2.18×104L.mol-1.cm-1(负吸收).若采用双波长叠加测定,灵敏度更高(ε为3.30×104L.mol-1.cm-1).探讨了反应条件、主要分析化学性质及三元缔合物的配位比.结合巯基棉分离富集方法,该体系用于垃圾渗滤液中镉的测定,结果满意.  相似文献   

9.
通过环己亚胺基二硫代甲酸钠与邻菲罗啉和硝酸铋反应,合成了新型的铋金属配合物邻菲罗啉合双-(环己亚胺基二硫代甲酸)-硝酸铋的单晶,通过X-射线单晶衍射仪测定了晶体结构,IR,元素分析,1H NMR,13C NMR等技术对结构进行了表征.结果表明该晶体属于单斜晶系,空间群P2(1)/n,晶胞参数为:a=1.163 2(2) nm,b=1.441 4(3) nm,c=1.768 1(3) nm,β=93.893(3)°,Z=4,V=2.957 8(10) nm3,Dc=1.796 g/cm-3,Mu=6.281mm-1,F(000)=1 576,R1 =0.043 9,wR2=0.093 0[I≥2σ(I)],在该配合物中,中心铋原子形成了畸变的加帽五角双锥八配位构型.  相似文献   

10.
二溴对甲基偶氮磺光度法测定铋   总被引:1,自引:1,他引:0  
研究了新显色剂二溴对甲基偶氮磺与铋的反应,建立了直接测定药物中铋的光度分析方法.在0.16mol/L高氯酸介质中铋与二溴对甲基偶氮磺迅速形成蓝色配合物,最大吸收波长634nm,表观摩尔吸光系数为2.41×10~4L/(mol cm),铋含量在0~35g/25mL范围内符合比耳定律,显色反应具有良好的选择性,主要共存离子有较大允许量,可用于药物中铋的测定.  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.
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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