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1.
在乙酸钠-盐酸缓冲液中,ClO2能氧化I-生成I2,过量的I-与I2形成I3-,阳离子表面活性剂(CS)十四烷基二甲基苄基氯化铵(TDMBA)、溴代十四烷基吡啶(TPB)、十六烷基三甲基溴化铵(CTMAB)、四丁基碘化铵(TBAI)等分别能与I3-形成缔合物微粒,分别在320、467、480、530 nm处产生共振散射效应.激光散射法测得(TDMBA-13).缔合物微粒的平均粒径为347 nm.ClO2分别在0.009 92~0.546、0.010 2~1.024、0.026 9~0.538和0.017 8~1.095 mg/L范围内与TDMBA、TPB、CTMAB及TBAI缔合微粒体系在467nm处共振强度成线性关系,各体系的检测限分别为0.005 93、0.006 00、0.019 8和0.064 5 mg/L ClO2.其中TDMBA体系最稳定,且灵敏度较高,用于水中ClO2的测定,结果满意.  相似文献   

2.
基于Fenton反应产生的羟基自由基(·OH)氧化过量的KI生成I3-.I3-分别与阳离子表面活性剂氯代十六烷基吡啶(CPC)、十六烷基三甲基溴化铵(CTMAB)、四丁基溴化铵(TBABr)、四丁基碘化铵(TBA1)、溴代十四烷基吡啶(TBP)、十四烷基二甲基苄基氯化铵(TDMAB)形成缔合物微粒,产生吸收峰.据此建立一种间接检测Fenton反应中羟基自由基的光度法.其中十六烷基三甲基溴化铵最稳定且灵敏,用它测定了模拟水样中羟基自由基和筛选抗氧化剂获得了满意的结果.  相似文献   

3.
在Britton-Robinson缓冲介质(pH 6.0)中,单独的葡聚糖硫酸钠和溴化十六烷基吡啶的共振瑞利散射都非常微弱,但当两者反应形成离子缔合物后,仅引起吸收光谱的微小变化,但却导致RRS显著增强,并产生了新的共振瑞利散射光谱,葡聚糖硫酸钠在0.01~2.8μgmL-1范围内与RRS强度成线性关系,由此建立了一种测定DSS的新方法.该方法灵敏度高,检出限达9.85ngmL-1.通过实验研究了适宜的反应条件和影响因素,考察了共存物质的影响,结果表明该方法有高的灵敏度和较好的选择性.  相似文献   

4.
合成了四种季铵盐型阳离子表面活性剂C22H45N(CH3)2C2H5Br(二十二烷基乙基二甲基溴化铵),C22H45N(CH3)2C4H9Br(二十二烷基丁基二甲基溴化铵),C22H45N(CH3)2C8H17Br(二十二烷基辛基二甲基溴化铵),C22H45N(CH3)2C12H25Br(二十二烷基十二烷基二甲基溴化铵),并考察了其对Rh-TPPTS[TPPTS:P(m—C6H4SO3Na)3]催化的水—有机两相长链烯烃氢甲酰化反应性能的影响.研究结果表明,在该体系中添加含有疏水长链的阳离子表面活性剂后,反应性能得到明显改善.  相似文献   

5.
十四烷基二甲基苄基氯化铵萃取金的研究   总被引:4,自引:3,他引:1  
用放射性核素^198Au示踪法研究了季铵盐十四烷基二甲基苄基氯化铵(TDMBA)从碱性氰化液中萃取金,考察了水相金浓度、助溶剂含量、萃取时间、季铵盐与KAu(CN)2摩尔比值nr等因素对萃取率的影响,并研究了有机相的连续萃取、有机相金含量与水含量的关系。结果表明,助溶剂体积比10%以上时,十四烷基二甲基苄基氯化铵对金具有萃取能力强,平衡时间短的特点。季铵盐阳离子与Au(CN)2^-结合比为1:1,  相似文献   

6.
采用4-氨基-十二烷基氯化吡啶(ALPC)、4-苯酰氨基-1-十二烷基溴化吡啶(BADPB)、4-(1-萘酰)氨基-十二烷基溴化吡啶(NADPB)3种季铵盐,用于经过染色或未染色的棉织物抗菌整理,对染料和吡啶季铵盐分子之间的作用力以及吡啶盐在染色织物上吸附量的影响因素进行了讨论.季铵盐与染色棉纤维上的磺酸基可形成离子键,与未染色的棉织物相比,该离子键可提高季铵盐在棉纤维上的吸附率与抗菌性采用AATCC 61-2005洗涤试验法,测试整理后棉织物的抗菌洗涤耐久性.  相似文献   

7.
本文研究合成三个结构有关的长碳链季铵盐:溴化十四烷基三甲铵(TTAB),溴化十六烷基三甲铵(CTAB)和溴化十八烷基三甲铵(STAB)并探讨其合成的反应条件.该类季铵盐对甘蔗有很好的增糖催熟效果.  相似文献   

8.
选用了四种季铵盐作为相转移催化剂:三甲基苄基氯化铵,三乙基苄基氯化铵,三丙基苄基氯化铵,三丁基苄基氯化铵,应用于由邻硝基氯化苯合成邻硝基苯甲醚反应中,测定了它们的假一级反应速度常数和反应活化能,求得了反应的活化焓△H~+、活化熵△S~+和活化自由能△G~+。利用季铵盐所具有的有机和无机特性,研究了大小不同烷基的季铵盐相转移催化剂的结构与反应速度常数之间的关系,并且测得四种季铵盐在水-油两相中的平衡分配比。  相似文献   

9.
刚果红光度法测定微量阳离子表面活性剂   总被引:6,自引:0,他引:6  
采用光度法研究了阳离子表面活性剂(CS)溴化十六烷基三甲铵(CTAB)、溴化十六烷基吡啶(CPB)与刚果红(CR)的显色反应。结果表明:在pH2.37的B-R缓冲液中,溴化十六烷基三甲铵(CTAB)、溴化十六烷基吡啶(CPB)均能与刚果红(CR)生成离子缔和物,最大吸收波长465nm,摩尔吸光系数分别为5.4×103 L.mol-1.cm-1(CTAB)、5.7×103 L.mol-1.cm-1(CPB),方法简便、快速,可用于水相中直接测定阳离子表面活性剂。探讨了酸度、温度、时间等反应条件对测定结果的影响,并应用于合成水样中进行微量阳离子表面活性剂的测定,取得满意的结果。  相似文献   

10.
采用熔融共混的方法分别制备了经两种有机插层剂(十八烷基季铵盐和双十八烷基苄基季铵盐)处理的交联聚乙烯/蒙脱土(XLPE/OMMT)纳米复合材料.不同插层剂处理的XLPE/OMMT纳米复合材料,介电谱表现出明显不同的特征:添加十八烷基季铵盐处理的蒙脱土,损耗峰为单峰;而添加双十八烷基苄基季铵盐处理的蒙脱土,损耗峰出现双峰.这与不同插层剂对蒙脱土在聚合物中的分散和插层效果有关.  相似文献   

11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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   

14.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

15.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

16.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

17.
18.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

19.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

20.
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   

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