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1.
发光分子水杨基荧光酮羧甲基纤维素铅微球(L-[(CMC)2Pb-THBF]-MB)在滤纸基质上可发射强而稳定的室温光.基于EDTA与Pb2 的络合反应,使L-[(CMC)2Pb-THBF]-MB微球转化为水溶性组分(PbY2-、2CMC-、THBF),该组分与痕量的Ag 作用生成(CMC)2Ag-THBF,导致S-L-[(CMC)2Pb-THBF]-MB的固体基质室温光猝灭,建立了发光分子水杨基荧光酮羧甲基纤维素铅微球固体基质室温猝灭测定痕量银的新方法.Ag 的含量在8.0~40.0 fg/斑(20.0~100.0 pg/mL)内与ΔIp值符合比尔定律,工作曲线回归方程为ΔIp=12.56 0.5527CAg (fg/斑),r=0.999 2,检出限为2.2 fg/斑.该方法用于人发、茶叶中痕量银的测定,结果满意.  相似文献   

2.
以CMCNa(羧甲基纤维素钠)为前驱体,掺杂水杨基荧光酮(THBF),Pb^2+为沉淀剂,用Sol-gel法合成发光分子水杨基荧光酮羧甲基纤维素铅微球(L-[(CMC)2Pb-THBF]).此微球在滤纸基质上可发射强而稳定的室温烧光,基于EDTA与Pb^2+络合反应,使L-[(CMC)2Pb-THBF]微球转化为水溶性组分(PbY^2+、2CMC^-、THBF),该组分与痕量的Ag^+作用生成(CMC)2Ag-THBF,导致S—L—[(CMC)2Pb—THBF]的固体基质室温烧光猝灭,据此建立了发光分子水杨基荧光酮羧甲基纤维素铅微球固体基质室温烧光猝灭测定痕量银的新方法.该方法用于人发、茶叶中痕量银的测定,结果满意.固体基质室温烧光测定银的反应机理。  相似文献   

3.
以NaCMC(羧甲基纤维素钠)为前驱体,掺杂水杨基荧光酮(THBF),Pb2 为沉淀剂,用Sol-gel法合成发光分子水杨基荧光酮羧甲基纤维素铅微球(简记为Pb(CMC)2–THBF).Pb(CMC)2–THBF在滤纸基质上可发射强而稳定的室温燐光(RTP).基于EDTA与Pb2 的络合反应,使Pb(CMC)2–THBF微球转化为水溶性组分(PbY2-、2CMC-、THBF),该水溶性组分与痕量上Pd2 作用生成(CMC)2 Pd–THBF,导致Pb(CMC)2–THBF上RTP猝灭,Pd2 上含量与△Ip值成线性关系,据此建立了Pb(CMC)2–THBF固体基质室温燐光猝灭燐上痕量钯上新方法.该方法上检出限为0.38fg/斑(对应浓度为9.5×10-13g/mL),工作曲线回归方程为△Ip=17.95 0.7847 C Pd2 (fg/斑),r=0.9989.本方法用于分子筛催化剂和黄矿石中痕量钯上燐上,结果满意.同时时时了固体基质室温燐光测定钯的反应机理.  相似文献   

4.
汞是环境监测的重要元素之一,由于环境试样中汞的含量很低,一般的分析方法难以直接测定.荧光光度法是一种用于分析化学的高灵敏度分析方法,在痕量分析领域中发展迅速,近年来,运用荧光光度法测定汞的研究报道不多[1~3].而水杨基荧光酮作为荧光试剂测定痕量汞尚未见报道.本文基于汞与水杨基荧光酮和邻菲啰啉生成三元配合物后,对水杨基荧光酮的荧光猝灭作用,建立了测定痕量汞的荧光分析新方法.实验表明,该方法具有较好的选择性和较高的灵敏度,用于环境水样中痕量汞的测定,效果良好.  相似文献   

5.
报道了包含桑色素(Morin)的SiO2纳米微球(Morin-SiO2)的合成方法,并用JEM-2000EX型透射电子显微镜检测其微球粒径,达到50 nm.基于Morin-SiO2能在滤纸固体基质上发射强而稳定的室温磷光,铋可使室温磷光猝灭,据此建立了Morin-SiO2固体基质室温磷光猝灭法测定痕量铋的新方法.铋的含量在0.16~14.4 ag/斑(浓度范围0.40~36.0 fg/ML,0.4 μL/斑)内与△Ip值成线性关系,方法检出限0.026 ag/斑(对应浓度6.5×10-17 g/mL),本法灵敏度高,重现性好,简捷快速,用于尿结石、人发样品的测定,结果满意.  相似文献   

6.
研究发现Ag+为离子微扰剂时3.5代树枝状分子(3.5-G-D)在滤纸固体基质上能发射稳定的室温磷光(RTP).在70℃、15min条件下,基于Cd-3.5-G-D配合物能催化KBrO3氧化3.5-G-D的反应,导致3.5-G-D的RTP信号剧烈猝灭,且△Ip与Cd2+含量成线性关系,据此建立了Cd-3.5-G-D配合物催化KBrO3氧化3.5-G-D固体基质室温磷光法(SS-RTP)测定痕量镉的新方法.该方法灵敏(检出限(LD)为1.2 ag spot-1)、准确、选择性好,适用于生物样品中痕量镉的测定.同时探讨了Cd-3.5-G-D配合物催化SS-RTP测定痕量镉机理.本研究揭开3.5-G-D新的应用领域,发展了新的SS-RTP.  相似文献   

7.
以1,8-萘酐和萘乙二胺为原料设计合成了一种新的铅离子荧光探针M1,并对其结构进行了表征.荧光光谱实验表明:在乙醇溶液中,M1对Pb2+表现出了识别性能,随Pb2+的加入,其荧光光谱强度发生明显猝灭,而对Na+、K+、Ag+、Hg2+、Cr3+等离子无明显响应.Job’s plot实验显示M1与金属离子形成结合比为1∶1的配合物,Pb2+在0~9×10-5 mol·L-1范围内,探针的荧光强度与其浓度成线性关系.  相似文献   

8.
利用一步法在水相中合成表面包裹谷胱甘肽的碲化镉(CdTe@GSH)量子点.所合成的CdTe@GSH量子点水溶性好,在水溶液中性质稳定.量子点具有较高的量子产率,并且可以通过控制反应条件使荧光光谱在整个可见光范围内可调.溶液中的铅离子能够造成CdTe@GSH量子点发生荧光猝灭,猝灭效率与铅离子浓度成正比.利用此现象发展出检测痕量铅离子浓度的方法,线性范围在0.5~500 nmol/L,检出限低至0.1/L,且具有较好的选择性.利用电喷雾-质谱和动态光散射研究了铅离子与CdTe@GSH量子点的相互作用,并探讨了量子点发生荧光猝灭的机理.  相似文献   

9.
研究了Ag(I)-phen-TPPS_4荧光体系,建立了痕量银的荧光测定新方法。在碱性介质中,Ag(phen)_2~ 络阳离子与TPPS_4 的阴离子形成三元离子对缔合物(Ag:Phen:TPPS_4=1:2:1),导致TPPS_4 的荧光(λex=413 nm,λem=638 nm)猝灭而定量测定银。也可直接测定缔合物的荧光(λex=438 nm,λem=648 nm)而定量测定银。两种测定方法在Ag(I)浓度为0~3 μg/25 ml范周内,工作曲线呈良好线性关系,方法的检出限前者为0.88 PPb,后者为5.2 PPb。用于废水中微量银的测定,变异系数6%,标准加入量的回收率 92~107%。  相似文献   

10.
基于100℃反应1.0min和pH=4.0HAC-NaAC缓冲溶液的条件下,NO_2~-与Griess试剂(对氨基苯磺酸,α-萘胺)反应生成红色偶氮化合物在固体基质上能发射强而稳定的室温燐光,Hg~(2 )能催化红色偶氮化合物致使其燐光激烈猝灭,且Hg~(2 )的含量与△Ip成正比,据此建立了红色偶氮化合物固体基质室温燐光猝灭法测定痕量Hg~(2 )的新方法.Hg2 的含量在0.0080~4.0(fg/spot)(对应浓度0.020~10.00pg/ml)范围内与△Ip符合比尔定律,检出限为4.1ag/spot(对应浓度1.0×10~(-14)g/ml),对0.0080和4.0(fg/spot)的Hg~(2 )进行8次平行测定,其RSD分别为3.6%与4.1%,本方法成功用于水中痕量Hg2 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.
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   

15.
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   

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.
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   

19.
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   

20.
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   

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