纳米掺杂Ag/SnO2复合材料物理性能的研究

研究了纳米氧化物掺杂对Ag/SnO2触头材料物理性能的影响.采用溶胶-凝胶法制备SnO2与各种掺杂氧化物(包括TiO2、ZnO、Sb2O3、CuO)的混合粉末.粉末的XRD、TEM表明,所得粉末为纳米级,且掺杂物离子能很好地进入到SnO2的晶格中;粉末的密度,电导率等测试表明SnO2的物理性能有了明显改善.     

TiO2掺杂Ag/SnO2电接触材料物理性能的研究

采用机械混合法、溶胶-凝胶法制备TiO2掺杂Ag/SnO2电接触材料。实验结果表明,在机械混合法中,Ti4 不能进入SnO2的晶格,也没有提高SnO2的电导率;在溶胶-凝胶法中,Ti4 能够很好地进入SnO2的晶格,从而改善触头的电性能。微观组织分析表明:纳米触头中SnO2的分布要比非纳米触头中SnO2分布均匀,可以避免因SnO2的富集而降低电导率,从而提高Ag/SnO2触头的电性能和电寿命。     

氧化镁和氧化钇掺杂对纳米氧化铝粉末的影响

本文研究了用均相共沉淀法合成氧化铝陶瓷粉末的同时合成氧化镁、氧化钇等掺杂氧化物,发现在掺杂量不大时,同时合成的掺杂氧化物以填隙固溶体方式固溶于立方γ氧化铝中,并且几乎不影响铝氧键性质、晶格常数和衍射波矢,但掺杂使氧化物细化,比表面增大,用此法合成的粉末聚集比较厉害,在粉末中有晶化颗粒存在．     

氧化镁和氧化钇掺杂对纳米氧化铝粉末的影响

本文研究了用均相共沉淀法合成氧化铝陶瓷粉末的同时合成氧化镁、氧化钇等掺杂氧化物,发现在掺杂量不大时,同时合成的氧化物以填隙固溶体方式固溶于立方γ氧化铝中,并且几乎不影响铝氧键性质,晶格常数和衍射波矢,但掺杂使氧化物细化,比表面增大,用此法合成的粉末聚类比较厉害,在粉末中有晶化颗粒存在。     

溶胶凝胶法制备纳米氧化物陶瓷研究现状

纳米氧化物陶瓷的制备技术一直是纳米陶瓷领域的重要研究课题.溶胶-凝胶法是制备纳米粉体的先进工艺,它具有工艺简单,设备成本低,反应过程可控,制备的粉体纯度高、均匀性好等一系列优点.本文综述了利用溶胶凝胶法制备TiO2、Fe2O3、SnO2、SiO2、Al2O3、ZrO2纳米陶瓷粉体的方法,并对溶胶-凝胶法制备这些纳米氧化物的优缺点进行了分析.最后,总结了目前溶胶-凝胶法制备纳米氧化物陶瓷粉体存在的问题,并对其未来研究方向进行了展望.     

两种不同形貌α-Fe2O3/SnO2复合材料的制备

利用水热法分别制备了α-FeO3纳米棒和立方体,并以其作为前驱物制备了α-Fe2O3/SnO2复合材料.样品的成份、结构、形貌和尺寸采用X-ray粉末衍射(XRD)和扫描电镜(SEM)等测试手段进行了表征.分析结果发现,α-Fe2O3前驱物的形貌能够影响α-Fe2O3/SnO2的最终形貌和结构.以α-Fe2O3纳米棒作为前驱物时,α-Fe2O3/SnO2复合材料是由棒状结构组成的团聚体;而以α-Fe2O3立方体作为前驱物时,在相同的制备条件下能够得到α-Fe2O3/SnO2球形粒子.最后对α-Fe2O3前驱物的形貌对α-Fe2O3/Sno2复合材料生长过程中的影响机理进行了探讨.     

一维SnO2纳米结构的电学性质

采用电场组装的方法将SnO2纳米线组装在Pt电极上,利用扫描探针显微镜（SPM）的导电AFM（C—AFM）模式对组装的SnO2纳米结构的电学性质进行了测量,所测得的SnO2纳米线的I—V曲线是非线性、非对称的。根据测量结果,得出SnO2纳米线与两个Pt电极之间形成了背靠背的肖特基势垒结构,并通过分析得出SnO2纳米结构的电流输运机制。     

SnO2纳米微粒的制备方法及其进展

综述目前SnO2纳米微粒的常用制备方法,简要分析了各类制备方法的基本原理及特点.在归纳、总结和比较的基础上,指出了制备SnO2纳米微粒有发展潜力和应用前景的方法,并对制备SnO2纳米微粒的发展前景作了简要的介绍.     

碳包覆的掺杂稀土Nd的Fe-Co合金纳米颗粒的合成、结构及磁性能研究

以水热法制备的不同稀土Nd掺杂量的铁钴合金/钴铁氧体纳米复合物为前驱体,用三聚氰胺作还原剂和碳源在高温条件下高纯氮气氛中合成出了碳包覆的掺杂稀土Nd的Fe-Co合金纳米颗粒。XRD表征结果显示,碳包覆的掺杂稀土Nd的Fe-Co合金纳米颗粒中Nd以氧化物Nd2O3的形式存在,TEM观察颗粒尺寸为50nm左右,VSM性能测试表明其饱和磁化强度随Nd掺杂量的增大而减小,矫顽力增大。     

纳米二氧化钛光催化降解空气中甲醛影响因素的研究

研究了在自制反应舱中纳米TiO2对室内空气中甲醛的光催化降解反应的影响因素，比较了载体对TiO2光催化降解甲醛速率的影响，发现泡沫镍网镍网最适合作为栽体。分析了掺杂的影响，发现活性炭和纳米掺锑氧化锡(ATO)粉末的加入能明显提高甲醛光催化降解速率。研究了粘结剂对TiO2光催化作用的影响，水玻璃的加入能够提高降解速率。     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

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?     

Western and Eastern culture differences in commercial field

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.     

只要努力,不要后悔

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.     

浅谈移民问题

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.     

Sister Carrie, an Adherent of Desires

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.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

风的曲线

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.