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1.
以环己烷为连续相,span-60为分散剂,硝酸铈铵/过硫酸钾(CAN/KPS)为复合引发剂,通过反相悬浮共聚法制备淀粉接枝丙烯酰胺絮凝剂.考察了引发剂用量、反应时间、单体用量、分散剂用量及反应温度等因素对接枝反应中单体转化率和接枝率的影响;并将该接枝共聚物用于对高浊度水的絮凝实验.结果显示接枝反应的最佳反应条件为:淀粉用量10 g,丙烯酰胺用量5 g,分散剂用量3 g,引发剂用量0.3 g(CAN/KPS=0.5,摩尔比),反应温度70 ℃,反应时间2 h;絮凝实验表明该淀粉接枝絮凝剂对高浊度水具有良好的絮凝效果.  相似文献   

2.
以淀粉和丙烯酰胺为原料,在离子液体氯化1-烯丙基-3-甲基咪唑中通过接枝共聚反应合成了丙烯酰胺-淀粉絮凝剂.研究了淀粉在离子液体和水中溶解情况的差异.通过傅立叶变换红外光谱证实了丙烯酰胺与淀粉分子发生了接枝共聚反应.考察了丙烯酰胺与淀粉的质量之比、引发剂用量、反应温度和时间对接枝共聚反应的影响.比较了在离子液体和水中合成得到的絮凝剂在高岭土悬浊液中的絮凝能力.  相似文献   

3.
研究了一种用于处理洗煤废水的改性絮凝剂。在该絮凝剂的制备过程中单体质量比与原料配比的影响最为显著,其次为引发剂的浓度,最小的为反应温度。处理洗煤废水最适宜的改性絮凝剂合成条件:1)接枝共聚反应中:玉米淀粉5g、淀粉∶丙烯酰胺(质量比)=1∶4、去离子水150ml、0.5×10-3 mol/L的硝酸铈铵5ml、接枝反应温度为50℃、反应时间3h。2)阳离子化反应中:丙烯酰胺∶甲醛∶二甲胺(摩尔比)=1∶1∶0.5、反应温度75℃、反应时间2h。在洗煤废水的处理过程中,采用改性絮凝剂与硫酸铁复配处理洗煤废水效果较好,投药量分别为5mg/L、60mg/L。用其处理后的洗煤废水沉降性能好,透光率高,COD去除率高,水质得到大大改善。因此,本絮凝剂具有良好的应用前景。  相似文献   

4.
阳离子淀粉改性絮凝剂的合成及性能评价   总被引:5,自引:0,他引:5  
以过硫酸铵/亚硫酸氢钠为引发体系,合成阳离子淀粉接枝丙烯酰胺、二烯丙基二甲基氯化胺(DADMAC)絮凝剂;采用正交试验确定淀粉接枝丙烯酰胺的最佳反应条件,引进阳离子单体DADMAC,合成一系列阳离子淀粉改性絮凝剂;以大庆油田三元复合驱污水为处理对象,考察阳离子淀粉改性絮凝剂的絮凝性能.结果表明:大庆油田三元复合驱污水适合在弱酸及中性的条件下处理,合适的pH值为6.0~7.0;单体DADMAC与可溶性淀粉质量比为1:9复配的絮凝剂效果最好,其质量浓度为50mg/L时,透光率达95%,对油、聚合物、悬浮物的去除达到了理想的效果.  相似文献   

5.
采用自由溶液聚合法,以KMnO4/H^ 为引发体系,研究了淀粉与丙烯酰胺和二甲基二烯丙基氯化铵的接枝共聚反应,考察了引发剂用量、酸度大小、淀粉加入量、单体浓度、反应温度等条件对接枝反应的影响,并用红外光谱对产物进行了结构特征。  相似文献   

6.
利用 Fe SO4 - H2 O2 体系作引发剂 ,引发芋艿细粉与丙烯酰胺接枝共聚反应。探讨了反应温度、反应时间、H2 O2浓度、丙烯酰胺浓度对接枝共聚反应的影响 ,同时研究了接枝物作高分子絮凝剂 ,对硅藻土悬浊液、洗煤废水、酒糟离心液的絮凝沉降性能  相似文献   

7.
Starch-g-PAM絮凝剂的反相乳液合成及应用研究   总被引:1,自引:0,他引:1  
以Span 80为乳化剂,过硫酸钾-尿素为引发剂,液体石蜡为油相,研究了淀粉与丙烯酰胺的反相乳液聚合.通过正交实验对各因素的考察得知油水比和乳化剂用量对实验的影响最大,其次是淀粉/丙烯酰胺(质量比)、引发剂用量,但搅拌速度和温度对实验的影响不太大.通过正交实验得出最佳反应条件为:油/水=1.2(体积比),淀粉/丙烯酰胺=1/2,乳化剂用量为(占整个连续相)6%,引发剂用量为1%,反应温度为40℃,搅拌速度为350 r.min-1,可得到最高接枝率为130%,最高接枝效率为93%,固含量为34.2%的接枝物,将所得接枝物处理造纸污水时,有较好的絮凝能力,且当絮凝剂投加量为30 mg.L-1时,絮凝效果最佳.  相似文献   

8.
为了研究淀粉-丙烯酰胺絮凝剂对铜、 镉离子的吸附性能,利用水溶液聚合法,以玉米淀粉、丙烯酰胺单体为原料合成淀粉-丙烯酰胺絮凝剂,并运用傅里叶红外光谱对絮凝剂的结构进行表征,同时考察絮凝剂用量、絮凝时间、pH值对铜、镉吸附性能的影响.结果表明:以硫酸铈为引发剂合成的淀粉-丙烯酰胺絮凝剂,当絮凝剂用量为0.5 g、絮凝时间...  相似文献   

9.
几种不同引发剂在玉米淀粉与丙烯酸接枝共聚中的应用   总被引:10,自引:2,他引:8  
研究了以硝酸铈铵,过硫酸铵,过硫酸铵-亚硫酸氢钠为引发剂玉米淀粉与丙烯酸的接枝共聚反应,对一些反应条件如引发剂浓度,反应温度,单体浓度,单体中和度,反应时间等进行了考察,并比较了以硝酸铈铵,过硫酸铵,过硫酸铵-亚硫酸氢钠为不同经发体系的淀粉与丙烯酸接枝共聚反应的结果,表明用过硫酸铵-亚硫酸氢钠为引发剂的引发效果最佳。  相似文献   

10.
γ辐射法制备壳聚糖接枝共聚物及其絮凝性能   总被引:2,自引:1,他引:1  
以壳聚糖(Cts)和甲基丙烯酸(MAA)为原料,应用γ射线辐射引发技术进行接枝共聚反应,制备了壳聚糖与甲基丙烯酸的接枝共聚产物(Cts-g-MAA),采用搅拌实验和测浊度法研究接枝改性壳聚糖对铅锌选矿废水的絮凝效果,其中考察了废水pH值、Cts-g-MAA的质量浓度、快速搅拌速度、慢速搅拌时间、静置时间对絮凝效果的影响,并将其与壳聚糖的絮凝能力进行了对比.实验结果表明,废水的pH值、絮凝剂质量浓度、搅拌速度、搅拌时间和静置时间均对絮凝效果产生影响,其最佳絮凝条件为pH值8.5、Cts-g-MAA浓度1.2mg/L、搅拌强度300 r/min、慢速搅拌时间为10 min、静置时间为11 min,此条件下的浊度去除率达98.6%.接枝改性壳聚糖的絮凝效果好于壳聚糖,且絮凝时的用量明显低于壳聚糖.  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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