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1.
采用分散聚合法,以甲醇/水混合溶液为分散介质,丙烯酸(AA)为单体,明胶为分散剂,经中和、引发和交联反应,合成了聚丙烯酸钠盐(PAANa)吸水高分子微球,经扫描电镜观测,其粒径在100μm-300μm,可吸去离子水310g/g,吸PH=4的酸性水为240g/g,吸pH的碱性水为265g/g,并讨论了分散介质,交联剂与分散剂用量及丙烯酸中和度等因素对吸水率的影响。  相似文献   

2.
两性聚电解质型高吸水树脂的合成及溶胀性能研究   总被引:1,自引:0,他引:1  
用溴己烷和甲基丙烯酸二甲胺基乙酯(DMAEA)合成N,N'-二甲基,N-己基甲基丙烯酰氧乙基溴化铵(DMAEA-HB),再采用这种含有烯丙基结构的不饱和季铵盐、丙烯酸(AA)和丙烯酰胺(AM)为原料,以过硫酸钾-亚硫酸氢钠(K2S2O8-NaHSO3)为引发体系,采用反相悬浮聚合法合成含有阴阳离子的两性聚电解质高吸水树脂(SAP),讨论了引发剂、交联剂、丙烯酸、丙烯酰胺、季铵盐用量、外部溶液pH值等因素对树脂吸液性能的影响.结果表明:在丙烯酸/丙烯酰胺(摩尔比)为1:1,季铵盐含量为2%,丙烯酸中和度为75%,交联剂用量为0.01×10-2(占单体的摩尔比),引发剂用量为1.00×10-3(K2S2O8/NaHSO3=1/1.1),反应温度为74℃的条件下,制得的SAP吸去离子水可达1 440g/g,吸0.9%的NaCl溶液为118g/g.与一般聚电解质高分子相比,两性聚电解质型吸水树脂的吸水率受外部溶液pH值的影响更为敏感.  相似文献   

3.
利用β 环糊精 (β CD)和十二烷基磺酸钠 (SLS)对Se与 2 ,3 二氨基萘的反应产物 4 ,5 二苯基并硒二唑 (记作Se DAN)的协同增敏作用 ,直接在水相中测定痕量硒 .最佳pH为 5~ 8,λex=3 79nm ,λem=540nm .Se含量在 0~ 0 .6μg/mL范围内与荧光强度成线性关系 .最低检出限 0 .0 0 1 μg/mL ,试验了多种常见离子的影响 ,干扰可以很好地消除  相似文献   

4.
载体自转晶B-Al-MFI型沸石膜的原位合成与表征   总被引:5,自引:0,他引:5  
在乙胺和水混合蒸汽相中 ,首次通过载体自转晶 ,在多孔玻璃片表面原位合成了B Al MFI型沸石膜 FEAM分析表明 ,沸石膜的化学组成为w(B2 O3 ) =3.7% ,w(Al2 O3 ) =0 .5 5 % ,w(SiO2 ) =95 .2 5 % ,w(Na2 O) =0 .5 0 % X 射线衍射和扫描电镜观察证明 ,膜中沸石晶体的取向是随机的 晶体尺寸约为 15~ 2 5 μm ,单层晶体厚的膜约为 10~ 2 0 μm 在焙烧除去有机模板剂后的沸石膜上 ,O2 和N2 的透过性分别为 0 .0 95× 10 -8和0 .15× 10 -8mol/ (m2 ·s·Pa) 计算的O2 /N2 的理想选择性 (0 .6 3)明显低于诺森扩散的理想选择性值 (0 .94)和透过原载体的理想选择性值 (0 .91)  相似文献   

5.
采用“水包水”型离子凝胶化原理法制备壳聚糖微囊,即室温下在有分散剂和助表面活性剂的介质中,以多聚磷酸钠(TPP)为交联剂,由壳聚糖(CS)制备了CS/TPP纳米微胶囊.探讨反应条件如壳聚糖浓度、多聚磷酸钠浓度、转速、分散剂、助表面活性剂的加入等对微囊的成型影响,通过透射电镜表征了微囊的成型、粒径及单分散情况.结果表明:“水包水”型离子凝胶法操作简单,不需要有机溶剂的特殊反应体系,在600 μL分散剂Tween-80和0.0400 g助表面活性剂PEG20000的介质中,当转速为200 r/min,pH =5.11,ρ (CS)=1.50 mg/mL,ρ(TPP) =0.50mg/mL,即ρ(Cs):ρ(TPP)=3:1时,有利于成囊.  相似文献   

6.
用溴乙烷和甲基丙烯酸二甲胺基乙酯合成N,N-二甲基,N-乙基甲基丙烯酰氧乙基溴化铵,并以此含取代乙烯基结构的季铵盐(DMAEA-EB)、丙烯酸(AA)和丙烯酰胺(AM)为原料,十八烷基磷酸单酯为分散剂.通过反相悬浮聚合法合成含有阴阳两种离子的高吸水性树脂(SAP),讨论丙烯酸、丙烯酰胺、季铵盐、引发剂、交联剂用量对产物吸水性能的影响,并以大肠杆菌(E.coli)、猪葡萄球菌(S.hyicus)为对象,初步讨论树脂的抗菌性能.结果表明在AA/AM=1/1,n(DMAEA-EB)=2%(占单体的摩尔百分数),引发剂用量为0.754%,交联剂用量为0.01%。丙烯酸中和度为75%,反应温度为70℃的条件下,制得的SAP吸去离子水可达1035 g/g.吸0.9%的NaCl溶液为114 g/g.当季铵盐含量为2%时,抗菌效果较好,抗菌率达90%以上.  相似文献   

7.
HPLC法测定双黄连片中绿原酸的质量分数   总被引:1,自引:2,他引:1  
探讨高效液相色谱法测定双黄连片中绿原酸含量的方法 ,控制其质量 .Shim -packVP -ODS(4 6mm× 15 0mm ,5 μm)色谱柱 ,流动相为甲醇 -水 -冰醋酸 (2 0∶80∶1) ,流速为 1 0mL/min ,检测波长为 32 7nm .绿原酸在 0 4 0 8~ 2 0 4 0 μg范围内呈良好的线性关系 ,回归方程为A =2 84 0 95 98C +6 894(r=1.0 0 0 ) ,平均回收率为 10 0 .98% (RSD为 1.13% ) ,重复性RSD为 0 .32 % .方法简便、快速、灵敏、准确、重现性好 ,可作为双黄连片中绿原酸的质量控制标准  相似文献   

8.
黄浦江和长江原水臭氧化工艺中BrO-3的生成   总被引:1,自引:0,他引:1  
针对黄浦江和长江原水,通过臭氧化小试实验研究副产物溴酸根(BrO-3)的生成.结果表明,黄浦江原水中含溴离子(Br-)较少,生成的BrO-3超标风险较低;而长江原水中Br-含量较高,为103.5 μg/L;1.6 mg/L初始溶解O3、pH 7.3、B-r 100 μg/L、25 ℃条件下,长江原水臭氧化30 min后生成了15.2 μg/L BrO-3,超过国家标准10 μg/L(GB 5749-2006)的限值规定.调低pH值、减少初始O3浓度、降低温度均有利于控制BrO-3的生成.长江原水臭氧化过程中ct值和BrO-3生成量之间线性关系较好.实验中OUT指标与BrO-3生成量的线性关系不明显,不可代替ct作为衡量BrO-3的标准.  相似文献   

9.
以 pH =9~ 11的条件下 ,用乙酸乙酯萃取电解—还原法生产的对氨基苯酚 (PAP)产品中的 4 ,4′—二氨基二苯醚 (DAPE) ,并以 2mol/LHCl将DAPE反萃取到水相中 ,在激发和发射波长分别为 2 5 4和 36 0nm条件下 ,荧光强度与DAPE的量成正比 ,线性范围为 30~ 180 μg/L ,检测限为 8.0 μg/L ,样品加标回收率为 78~ 95 % .  相似文献   

10.
陆地  夏清  万峰  徐亮 《甘肃科技》2011,27(9):50-52
以碳纳米管为分散相材料,以乙二醇水溶液为分散介质,采用"两步法"可以制备出用于直接吸收式太阳集热器的新型吸热与传热循环工质——碳纳米管悬浮吸热黑液流体。该黑液流体的分散稳定性主要受到分散介质的组成、碳纳米管粒子的含量、分散剂的属性和含量、分散方式以及分散时间等因素的影响。当水乙二醇配比为2∶3、超声波分散45m in、分散剂聚丙烯酸钠浓度1.5g/L、碳纳米管加入量0.1%时,黑液流的分散稳定性是最好的,可以维持较长的时间。  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.
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   

14.
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   

15.
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   

16.
17.
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   

18.
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   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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