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给出了图C_4×C_4、C_4×C_5、C_5×C_5的一种全染色,从而得到了C_4×C_4、C_4×C_5、C_5×C_5的邻点可区别的全色数为6. 相似文献
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KD4-1、Z4、KD4-2、KD4-4、H95-1等新品系优于对照品种NC89，KD4-1表现最好，KD4-3次于对照NC89，表现最差。 相似文献
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刘效平 《中学生数理化(高中版)》2011,(6):26-26
中学化学出现的气体有：H2、N2、O2、O3、F2、Cl2、He、Ne、Ar、Kr、Xe、CH4、NH3、HF、SiH4、PH3、H2S、HCl、HBr、HI、CO、CO2、N2O、NO、NO2、N2O4、SO2、C2H6、C3H8、C4H1O、C2H4、C3H6、C4H8、C2H2、C3H4、C4H6、HCHO、CH3Cl等． 相似文献
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对4个选修专题：4—1几何证明选讲、4—2矩阵与变换、4—3坐标系与参数方程、4—5不等式选讲的2014年高考试题进行了系统整理,分析了考题的特点、亮点． 相似文献
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单酯基芳香醛及芳香腈类液晶的合成与液晶相研究 总被引：1，自引：0，他引：1
以对羟基苯甲醛、对羟基苯腈,与4-正丙基苯甲酸、4-正丙基联苯甲酸为主要原料,通过氯化、酯化等方法,合成了四个多环单酯基类液晶：4-正丙基苯甲酸-4′-氰基苯酚酯,4-正丙基苯甲酸-4′-醛基苯酚酯,4-（4-（4-正丙基联苯）酰氧基）苯甲醛,4-4-（4-（4-正丙基联苯）酰氧基）苯腈。产物结构经元素分析、IR及MS表征,化合物的液晶相通过DSC及POM（偏光显微镜）确定。结果表明其中2个化合物具有热致液晶性,呈典型的向列项纹影织构。 相似文献
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市场营销组合(marketing mix)理论从提出到发展至今有着很多的理论。但是,迄今为止理论界比较认可的仍然是4P、4C、4R市场营销组合理论。在理论的发展中,企业采用什么样的营销策略已经不是单一的4P、4C、4R,而是综合三种营销组合策略进行具体的策略设计。 相似文献
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实验研究了FeCl3·6H2O、Fe(So4) 3·XH2O、CuCl2·2H2O、NaHSO4·H2O、TiSO4、SnCl4·5H2O、AlCl3·6H2O、ZnSO4·7H2O、CuSO4·2H2O等几种无机盐对乙酸与正丁醇酯化反应的催化剂的催化性能的影响.结果表明:FeCl3·6H2O、Fe(SO4)3·XH2O、CuCl2·2H2O、NaHSO4·H2O、TiSO4、SnCl4·5H2O、AlCl3·6H2O都是较好的催化剂,同时,研究了以上几种无机盐催化剂合成乙酸正丁酯的最佳反应条件、特点并得出用以上催化剂重新组合的FeCl3-CuCl2,Fe(SO4)3-CuCl2按质量的2:1组合成混合催化剂重复性更好. 相似文献
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鲍晓东 《北京工业职业技术学院学报》2007,6(4)
以一吨4×4载货汽车的设计为例,对特殊性能进行专门系统的理论分析,寻求比较合适的4×4载货汽车的设计要点.通过计算分析,得出在轴距的选择、轮距的确定、动力总成及各大总成的布置、横向稳定杆的选择、汽车的摆振控制等方面应重点考虑,才能使4×4载货汽车设计趋于合理. 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