共查询到20条相似文献，搜索用时 62 毫秒
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对硝基苯酚在三乙醇胺改性煤渣的界面行为研究 总被引：1，自引：0，他引：1
用TEA改性制得了一系列改性煤渣，表征了改性煤渣的表面结构特征，研究了对硝基苯酚在改性煤渣／水间的界面行为，并探讨了其吸附机理，结果表明，用TEA制得的改性煤渣，表面羟基含量增加，有机碳含量也增加，对硝基苯酚在其表面的吸附以形成氢键为主的多层吸附。 相似文献
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化学改性活性炭对Cu(Ⅱ)离子吸附性能的研究 总被引：2，自引：0，他引：2
将市售粉状活性炭用16%硝酸进行氧化,再用0.1mol.L-1的氢氧化钠进行处理,制得化学改性活性炭,并对其吸附性能进行了研究.实验结果表明,改性后的活性炭较改性前对Cu2 离子的吸附能力提高60%以上. 相似文献
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通过对粉煤灰的硫酸改性得到酸改性粉煤灰,用其对含铅模拟废水进行吸附实验,探讨改性的最佳条件,并在最佳改性条件下制得改性粉煤灰,研究改性粉煤灰投加量、吸附时间、吸附温度以及pH值对Pb2＋吸附效果的影响.结果表明,在投加量为10 g/L,吸附时间为50 min,吸附温度为50℃,pH-6时,改性粉煤灰对40 μg/mL的Pb2＋的去除率可达90.34％,能够较好的去除废水中的Pb2＋. 相似文献
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《赤峰学院学报(自然科学版)》2020,(4)
以MgCl_2和Na_2SiO_3·9H_2O为原料合成硅镁胶,用氨水、1:1盐酸和冰醋酸进行改性,得到三种改性硅镁胶和一种未改性硅镁胶.分别测定其在不同反应时间、不同浓度和不同温度下对Cu~(2+)的吸附性能.结果表明:Cu~(2+)溶液浓度为0.005mol/L(pH=5.05)时,经由氨水改性的硅镁胶在40℃、搅拌1.5h时,吸附性能最好,理论吸附量最高;经由醋酸改性的硅镁胶在60℃和搅拌1.25h时,吸附量最高;经由盐酸改性的硅镁胶在20℃和搅拌1.5h时,吸附量最高;未改性硅镁胶在温度为50℃和搅拌1.5h时,吸附量最高. 相似文献
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《绵阳师范学院学报》2018,(11):64-68
以甲醛/硫酸为改性剂,对龙眼壳活性炭进行改性制备吸附剂(LCSF),并用LCSF对模拟废水中的Pb(Ⅱ)进行吸附,考察了Pb(Ⅱ)初始质量浓度、p H值、吸附时间、吸附温度对铅吸附量的影响.结果表明LCSF提高了对Pb(Ⅱ)的吸附性能,最佳工艺条件为:荔枝壳活性炭用量0. 05 g、铅初始浓度为120 mg/L、p H=5、吸附时间45 min、吸附温度298 K,在此工艺条件下,改性龙眼壳活性炭对Pb(Ⅱ)的吸附量可达229. 72 mg/g.该吸附过程符合准二级吸附动力学模型,其热力学参数△G <0、△H> 0、△S> 0,说明该吸附是自发的吸热吸附过程. 相似文献
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《绵阳师范学院学报》2015,(8):73-79
采用L-丙氨酸对壳聚糖进行改性,制备了改性壳聚糖,并研究了改性壳聚糖对水溶液中Sr2+的的吸附性能.结果表明:在吸附时间80 min,吸附温度50℃,吸附剂用量0.1 g,p H值为10时,L-丙氨酸改性壳聚糖对Sr2+吸附的的吸附率可达31.800%,吸附量为11.925 mg/g;L-丙氨酸改性壳聚糖微球对高浓度Sr2+的吸附量最大可以达到30.650 mg·g-1,吸附率最高可达83.3%;等温吸附结果表明,L-丙氨酸改性壳聚糖微球对Sr2+的吸附符合Langmuir等温吸附方程;L-丙氨酸改性壳聚糖对Sr2+的吸附过程与准二级动力学具有较高的相关性. 相似文献
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对改性粉煤灰处理含铅废水进行了实验研究,结果表明,对铅离子的去除效果优于等量未改性粉煤灰和活性炭。吸附时间、废水的pH值、吸附剂用量、温度以及废水中Pb2＋浓度都能影响改性粉煤灰的吸附效果。最适宜的吸附条件是：在室温,pH=8．0,吸附剂用量为1．0g,Pb2＋含量小于0．005mol／L,吸附15min时,改性粉煤灰对废水中Pb2＋的吸附达到饱和。 相似文献
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《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help? 相似文献
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《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love. 相似文献
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Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject. 相似文献
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Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities. 相似文献
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RUZBEHANI Mohsen 《重庆大学学报(英文版)》2004,3(1):20-25
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec… 相似文献
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唐芳 《读与写:教育教学刊》2008,5(6)
During interview with English majors, it was found that a majority of students expressed disappointment with their experience of English literature classes. Students' dislike of learning English literature appears to be the major problem of teaching English literature in China. Reader response approach is a good way to solve this problem. In this paper, I explain the rationale behind the reader response approach, such as its origin, definition, features, assumptions, and strategies. Then I illustrate how reader response approach works as a teaching strategy by presenting several teaching models. At last I evaluate its usefuiness for teachers and present the advantages of reader response approach in Chinese context. 相似文献