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1.
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   

2.
三元共聚尼龙与丙烯酸乙酯的接枝共聚反应研究   总被引:1,自引:0,他引:1  
以高锰酸钾/硫酸为引发剂,对尼龙6、尼龙610、尼龙1010三元共聚物与丙烯酸乙酯进行接枝共聚反应. 研究了接枝参数与时间、高锰酸钾浓度、硫酸浓度及反应温度的关系. 实验表明,当高锰酸钾浓度为0.025mol/L,H2SO4浓度为0.24mol/L,反应温度60℃,时间3h时,接枝率较高. X射线衍射检验表明,接枝后产物的结晶度由原来的47.8%下降到21.4%. 投料次序也直接影响接枝反应的进行.  相似文献   

3.
本文以过硫酸钾一硫脲为引发剂,研究了丙烯酸乙酯与吉林产亚麻纤维的非均相接枝共聚反应。过硫酸钾(KPS)的浓度为0.015mol/L,硫脲(TU)浓度为0.0002mol/L,单体(Mo.)浓度为0.2159mol/L,硫酸(H_2So_4)浓度为0.01mol/L时,在60℃,反应2小时可以得到较高的接枝率。  相似文献   

4.
改性粉煤灰对甲基橙的吸附及再生性能研究   总被引:1,自引:0,他引:1  
用浓度为2.0mol/L的盐酸,在常温、酸灰质量比为1:3的条件下对粉煤灰进行改性,改性后作为废水中甲基橙的吸附剂.当改性粉煤灰用量为50g/L、温度为30℃、pH值为4时,甲基橙的去除率为98%左右.用0.1mol/L的A12(SO4)3对吸附后的粉煤灰进行再生实验,效果良好.再生粉煤灰对甲基橙的去除率仍能达到95%.  相似文献   

5.
为了提高炭黑在水性介质中的分散性,利用对苯酚磺酸(p—PS)及低聚对苯酚磺酸(SPV)羟基邻位的活泼氢与羟甲基的反应,将炭黑羟甲基化后,研究了炭黑粒子表面导入亲水性基团的表面化学改性方法。研究了反应时间、反应溶剂对接枝率的影响,并在水浴90℃,催化剂存在下,水/甲醇为溶剂,反应3h,得到了接枝率为13%的改性炭黑。通过阿R、TEM等手段对P—PS和SPF改性炭黑进行了表征;未经改性的炭黑5min即会完全沉降;P—PS改性炭黑,在自然沉降15d后,分散液透光率从1.5%增加到11.4%;接枝率为13%的SPF改性炭黑,分散液透光率从43.4%变为65.8%。结果表明:改性炭黑在水中的分散稳定性大大提高。  相似文献   

6.
色素炭黑表面聚丙烯酸接枝改性制备染料   总被引:3,自引:0,他引:3  
作者提出了一种基于改性炭黑的新型染料的制备方法,首先,将羟基引入到炭黑表面,然后以Ce^4 为催化剂实施丙烯酸(AA)与炭黑的接枝聚合;分析与测定了接枝状况和产物的接枝率,结果表明,经上述方法改性的炭黑具有良好的水分散性和染色性。  相似文献   

7.
炭黑对于沥青混合料的高温稳定性和低温抗裂性有很好的改性效果,但对于其水稳定性改性效果不明显;而硅烷偶联剂可以用于提升路面的抗水损能力,所以提出将炭黑和硅烷偶联剂同时加入沥青混合料中,研究复合改性沥青的路用性能。采用响应曲面法设计试验,进行试验,然后分析结果,得到合成炭黑/硅烷偶联剂复合改性沥青的最佳改性条件;并通过车辙试验、真空饱水马歇尔试验及小梁低温弯曲试验来研究炭黑/硅烷偶联剂复合沥青混合料的路用性能。借助响应曲面法,得出了制备炭黑/硅烷偶联剂复合改性沥青的最佳炭黑、硅烷偶联剂的用量及剪切时间;通过车辙试验、马歇尔实验及低温小梁弯曲试验得出炭黑/硅烷偶联剂复合改性剂可有效地提升沥青混合料的高温稳定性、水稳定性和低温抗裂性;其中硅烷偶联剂主要提高了其水稳定性和高温稳定性,而炭黑主要是提高了沥青混合料的低温抗裂性能和高温稳定性。  相似文献   

8.
炭黑对于沥青混合料的高温稳定性和低温抗裂性有很好的改性效果,但对于其水稳定性改性效果不明显,而硅烷偶联剂可以用于提升路面的抗水损能力,所以本文提出将炭黑和硅烷偶联剂同时加入沥青混合料中,研究复合改性沥青的路用性能。采用响应曲面法设计试验、进行试验然后分析结果,得到合成炭黑/硅烷偶联剂复合改性沥青的最佳改性条件,并通过车辙试验、真空饱水马歇尔试验及小梁低温弯曲试验来研究炭黑/硅烷偶联剂复合沥青混合料的路用性能。借助响应曲面法,得出了制备炭黑/硅烷偶联剂复合改性沥青的最佳炭黑、硅烷偶联剂的用量及剪切时间;通过车辙试验、马歇尔实验及低温小梁弯曲试验得出炭黑/硅烷偶联剂复合改性剂可有效地提升沥青混合料的高温稳定性、水稳定性和低温抗裂性;其中硅烷偶联剂主要提高了其水稳定性和高温稳定性,而炭黑主要是提高了沥青混合料的低温抗裂性能和高温稳定性。  相似文献   

9.
自由基引发棉接枝丙烯酰胺的研究   总被引:1,自引:0,他引:1  
以过硫酸钾为引发剂,研究了丙烯酰胺在纯棉织物上的接枝共聚反应,研究了轧余率、引发剂浓度、单体浓度、反应温度时间和焙烘温度时间对接枝率的影响.得出了接枝共聚反应的最佳工艺条件:轧余率为70%;丙烯酰胺的浓度0.6mol/L;过硫酸钾浓度0.35mol/L;反应温度为50℃;反应时间不超过2min;焙烘温度120℃,焙烘时间5min.利用红外、热重分析等对接枝织物的结构与性能进行了表征,结果表明纯棉织物可以有效地接枝共聚丙烯酰胺,且接枝物的热稳定性明显升高,而白度无明显变化.图10,参9.  相似文献   

10.
采用原位液相接枝技术在炭黑表面接枝聚乙二醇400,研究了接枝前后炭黑补强天然橡胶的性能.结果表明:在相同填料添加量下,填充接枝改性炭黑的胶料焦烧时间和正硫化时间有所缩短,物理机械性能明显改善;当添加50份填料时,相比于添加未改性炭黑的胶料,填充接枝改性炭黑胶料的结合胶含量提高了16.5个百分点,拉伸强度和撕裂强度分别提升了6.1MPa和19.5kN/m,绝对磨耗质量由0.53g下降至0.37g,硫化胶在0、60和80℃时的tanδ分别下降了16.67%、45.23%和45.45%.动态力学测试和SEM分析表明,胶料性能提升的主要原因是接枝改性炭黑在橡胶基体中分散性的改善及炭黑与橡胶间相互作用力的增加.  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.
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   

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 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   

15.
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   

16.
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   

17.
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   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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