共查询到20条相似文献，搜索用时 46 毫秒
1.
EM和高分子絮凝剂对庆大霉素生产废水进行处理，结果显示单独使用EM时最佳的接种量是0．3％～0．4％，pH为8，处理时间为36小时，处理温度取自然温度(室温)，经正交实验最佳组合为B3A3C1，即最佳的温度为30℃，最佳接种量为0．5％，最佳pH为5。处理后COD从20000mg／L降至1000mg／L左右，经高分子絮凝剂处理最佳的pH为8.／10000的絮凝剂聚丙烯酸钠加量为0．75～1．0mL／250mL废液，沉降时间为1．5～2．0h，主要污染指标COD降低到了350mg／L，达到了国家排放标准(≤350mg／L)。 相似文献
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张一平 《浙江教育学院学报》2012,(3):103-108
基于K2Cr2O2能获得光生电子从而提高半导体光催化氧化能力的原理,建立了一种用纳米Ti02-K2Cr2O2协同体系光催化氧化,分光光度法测定染料浓度的简便方法．探讨了光催化氧化测定染料浓度的机理,考察了染料消解的最佳反应条件．最佳的消解条件为pH=1,TiO21．0g／L,K2Cr2O7初始浓度8．0mmol／L,溶液温度80℃,紫外光照时间10min．当Cl^-含量在1000mg／L以内时,相对误差小于3％． 相似文献
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木瓜蛋白酶酶解法捉取大枣多糖的工艺研究 总被引：2，自引：0，他引：2
对木瓜蛋白酶酶解法提取大枣多糖的工艺进行了研究。结果表明，大枣多糖的最佳提取工艺条件为：酶浓度0．5mg／mL，酶解温度55℃，pH=7，酶解时间2．5h。 相似文献
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当二氧化硫脲用量是还原Cu^2＋为Cu与还原Cr^5＋为Cr^3＋理论值总和的两倍时,使用二氧化硫脲在石灰饱和溶液（pH≈12．8）、沸腾条件下处理铜铬电镀废水,废水中Cu^2＋从31mg／L降为0．4mg／L,Cr^5＋从23mg／L降为0．017mg／L,总铬量由35mg／L降为5．3mg／L,经分析沉淀物为Cu（黑色）、Cu2O、Cr（OH）3趁热过滤后,往滤液中加入FeSO4·7H2O,调节pH至中性,鼓入空气,冷却至得到黑色铁氧体沉淀．经处理后残铜量为0．2mg／L,总铬量为0．035mg／L,PO4^3-由5mg／L降为1mg／L．各项指标优于工业排放标准． 相似文献
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以水解度为优化的指标,利用单因素试验研究酶解温度、pH值、反应时间等因素对鱼蛋白水解的影响,利用中心组合试验方法优化酶的添加量和蛋白质浓度．结果表明：复合蛋白酶水解罗非鱼的最佳条件为：加酶量17660U／g蛋白、蛋白质质量分数2．50％、水解温度55℃、pH值7．5、水解时间10h,在此条件下,水解体系的氨基酸态氮含量达到了1．41mg／mL,水解度为35．25％,挥发性盐基氮含量为0．048mg／mL,得到用复合蛋白酶水解罗非鱼的最佳工艺条件． 相似文献
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磁流体对工业废水中Cr（Ⅵ）的吸附 总被引：1，自引：0，他引：1
采用共沉淀法制备了粒径为10nm的Fe3O4磁性微粒,分散于水中生成饱和磁化强度35mT的水基磁流体,用此磁流体对模拟与实际废水中Cr（Ⅵ）进行了吸附研究。结果表明,吸附的最佳实验条件为pH=3,温度为45℃,吸附时间为0．5h。用Langmuir等温模型和假二级动力学模型探讨了磁流体对Cr（Ⅵ）的吸附机理,该过程为单离子层吸附。在最佳实验条件下,磁流体对实际制革废水中Cr（Ⅵ）的饱和吸附量达66．5mg／g,废水中残N／Cr（Ⅵ）浓度为0．2mg／L,低于工业废水排放的国家标准（0．5mg／L）。 相似文献
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采用Fenton法处理弱酸艳红B染色废水。通过单因素实验和正交实验,研究反应温度、初始pH值、H2O2和FeSO4投加量及反应时间对色度和COD去除率的影响。结果表明,各因素对COD去除率的影响从大到小依次为：反应温度〉pH值〉H2O2投加量〉FeSO4投加量。而处理废水的最佳条件为：反应温度50℃、初始pH值为2．5、30％H2O2投加量为5mL／L、FeSO4投加量为500mg／L、反应时间为90min。在此条件下,废水色度去除率为99．0％,COD去除率为74．2％。 相似文献
9.
严聃 《湖南科技学院学报》2009,30(4)
研究了用发酵法从米糠中提取高浓度γ-氨基丁酸的富集技术。通过实验的设计得出米糠提取液的最佳提取条件：米糠在pH=6．0,温度50℃水浴抽提4小时所得GABA含量可达到110mg／100ml,最佳发酵条件为：pH=6．0,温度45℃加入保加利亚乳酸杆菌发酵16小时可以使含量增加至114．2mg／100ml。 相似文献
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崔绍波 《辽宁科技学院学报》2016,18(3)
通过正交试验,以硫酸镍和硫酸铜为主盐、次磷酸钠为还原剂研究了铝片表面的化学镀Ni－Cu－P工艺,其最优工艺配方为：硫酸镍25 g／L,硫酸铜2．0 g／L,次亚磷酸钠24 g／L,柠檬酸钠45 g／L,硫脲2．5mg／L,NaF 0．15 g／L,OP－100．8 mg／L,pH值9,温度70℃,施镀时间40min。通过耐硝酸变色试验检测了沉积层的抗蚀性,并讨论了沉积层抗蚀性的影响因素。 相似文献
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邱崇丙 《唐山师范学院学报》2014,(1):21-23
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。 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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Rachel Zupek 《海外英语》2007,(11):40-41
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了 相似文献
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YANGShiguo 《重庆大学学报(英文版)》2004,3(1):86-88
The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex. 相似文献
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Rajesh Kanoi 《海外英语》2007,(1):52
Today, Sunday morning, I sit thinking and typing at my computer. My thoughts are in my homeland, India and my body is in China. The body is here and mind there for a good reason. Mr. Hu is president and I am resident and both are in each other's countries (what a difference the absence of one small letter makes!). Mr. Hu will return in a few days and I will stay on longer. 相似文献