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固相反应制备纳米氧化铜 总被引：7，自引：0，他引：7
以CuCl2·2H2O、Cu(NO3)2·3H2O与NaOH为反应物,在室温下通过固相化学反应合成CuO纳米粉体的两个反应体系,用透射电镜(TEM)和X射线衍射(XRD)对产物的组成、大小及形貌进行表征.结果表明:经室温固相化学反应所制得的CuO为单斜晶纳米CuO.另外,还从研磨方式、反应配比、反应体系、分散时间、及表面活性剂用量等方面对影响产物粒径大小及分散性的因素进行了探讨以下为所得结论的简要介绍:①反应速度是影响粒径大小的主要因素;②反应配比对产物的均匀程度及分散性有影响;③超声波分散可改变颗粒的分散程度;④表面活性剂的加入对改变颗粒的分散性有明显作用,其用量对粒径大小的影响存在最佳值. 相似文献
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25gFeSO4&;#183;7H2O溶于75g水中所得溶液的质量为100g，由于在FeSO4&;#183;7H2O的溶解过程中，其中的结晶水转化成了溶剂的一部分，因此，所得溶液的溶质已不再是FeSO4&;#183;7H2O，而是FeSO4，质量小于25g，故所得溶液中溶质的质量分数小于25％。符合题意的选项为C。 相似文献
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用半微量相平衡方法研究了Zn(NO3)2-Thr-H2O三元体系 的浓度图和饱和溶液折光率曲线，并绘制了相图，合成了制备了未见文献报道的三种配合物：Zn(Thr)NO3)2&;#183;2H2O(A)、Zn(Thr)2(NO3)2&;#183;H2O(B)、Zn(Thr)3(NO3)2&;#183;H2O(C). 相似文献
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《淮北师范大学学报》2015,(4)
以Ce(NO3)3·6H2O为前驱体,十二烷基硫酸钠(SDS)为结构导向剂和碳源,用固相法在有氧环境和低温条件下,制备Ce O2@C纳米核壳结构.XRD、FESEM和TEM分析表明,产物粒径在10~30 nm,并且具有一定的多面体外形,表面碳层约2 nm.结果表明,利用SDS的—SO4-基团和Ce3+的键合作用,能够诱导Ce O2的有序生长,形成具有特定晶面的纳米颗粒. 相似文献
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叶素芳 《金华职业技术学院学报》2009,9(3):54-57
以牛血清白蛋白为稳定剂,CdSO4·8H2O、硫脲、NaOH室温固相反应制备CdS,用XRD、TEM、原子力对粒子进行表征表明,得到单分散立方相球状CdS纳米粒子。还表明。牛血清白蛋白加入的量及加入方式对粒子的大小、粒径分布、分散程度有影响。随牛血清白蛋白加入的量的增加,粒子变小,粒径分布更均匀,分散程度提高;且在固相反应物中加入牛血清白蛋白一起研磨比粒子制成后水相中再加入牛血清白蛋白更有利于粒子的粒径分布均匀和分散。 相似文献
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本文以NiSO4．6H2O、NaOH和H2为原料,采用低温固相法制备了分布均匀、平均粒径在20～35nm纳米镍粉,并采用XRD、TEM、SEM和XPS等微观分析手段对产物表面结构和价态进行了表征．研究了纳米镍粉加氢还原硝基苯制备苯胺体系中温度、氢压力、催化剂用量等因素对转化率的影响,并和RaneyNi做了比较．结果表明：纳米镍粉催化加氢活性高于RaneyNi,是同条件下RaneyNi的9倍左右;催化剂用量在4％wt-6％wt之间,温度为120℃为还原的最佳条件,同时也发现氢压力对转化率也有着较大影响．当压力达到0．8Mpa时,硝基苯转化为苯胺的转化率率高达76．42％． 相似文献
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用无水Na2CO3与加有表面活性剂的AlCl3.6H2O室温下进行固相反应,合成得到碱式碳酸铝钠纳米材料和可溶性无机盐,用水洗去可溶性盐,烘干,即得到碱式碳酸铝钠纳米晶体。用均匀试验设计方法安排试验方案,用多元逐步回归法建立数学模型,并用网格优化法确定了最佳的试验条件。产物最终经XRD表征,证实为纳米尺寸晶体。 相似文献
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《淮北师范大学学报》2016,(3)
以Na_2WO_4·2H_2O和Zn(NO_3)2·6H_2O为原料,利用机械球磨固相反应技术,制备纳米ZnWO_4光催化剂.通过X-射线衍射仪(XRD)、透射电子显微镜(TEM)对所制得样品的物相和形貌进行表征,研究制备条件对产物组成和结构的影响,并对其光催化性能进行初步探讨.结果表明,在室温条件下,不需要添加任何辅助试剂,采用机械球磨固相法成功地制备出ZnWO_4纳米片.同时,光催化实验也表明,ZnWO_4纳米片在紫外光照射下具有较好的光催化性能,3 h后甲基橙的降解率达到91%. 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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罗艳萍 《读与写:教育教学刊》2008,5(6)
The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity. 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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Richard Denner 《海外英语》2007,(4):14-15
Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose. 相似文献
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Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F. 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