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1.
本文用热重法考察了三种不同孔道结构的分子筛(SAPO-34,SAPO-5,HZSM-5)在乙醇转化为低碳烯反应过程中的积炭行为,以及经钾、镁的化合物改质的SAPO-34分子筛在该反应过程中的抗积炭能力。用氨程序升温脱附法(TPD)研究了它们在积炭前后的酸性变化。  相似文献   

2.
PERFORMANCESIMULATIONANDANALYSISOFAQUAAMMONIAABSORPTION-RESORPTIONHEATPUMPDuKai(杜垲)YangSiwen(杨思文)ZhangSiqun(张思群)(Departmentof...  相似文献   

3.
MICROSTRUCTUREANDMECHANISMOFANEWTYPEOFNi-Fe-W-P-SWEAR-RESISTANTBRUSHPLATINGLAYERHuiWenhua(惠文华)ZhangJinping(张瑾平)ShaoLiwei(邵力为)...  相似文献   

4.
第二讲DOS(一)□李雪梅一、DOS5.0及DOS6.0的性能特点相对于DOS3.3,MS-DOS5.0有如下新的特性:1.增强型内存管理,使程序的运行更快,更有效。2.支持更大的磁盘容量。硬盘分区最大容量可达2GB,还能支持2.88MB软盘。3.M...  相似文献   

5.
ANALYSISOFTHEFIELDSSCATTEREDFROMATWO-DIMENSIONALCYLINDERILLUMINATEDBYAPOINTSOURCEChengChonghu(程崇虎)ZhangWenxun(章文勋)(StateKeyLa...  相似文献   

6.
ONTHECONVERGENCEOFGUMMELMAPPINGFORSTEADY-STATESEMICONDUCTOREQUATIONSGuanPing(管平)WangYuanming(王元明)(DepartmentOfMathematicsandM...  相似文献   

7.
AMINI-CAPACITANCEPROBEFORMEASURINGTHELOCALVOIDFRACTIONINGAS-SOLIDFLUIDIZEDBEDSGuiKeting(归柯庭)HanJitian(韩吉田)ShiMingheng(施明恒)(De...  相似文献   

8.
AMODIFIEDCRANK-NICOLSONSCHEMEFORTHEINITIAL-BOUNDARYVALUEPROBLEMOFSUPERTHERMALELECTRONTRANSPORTEQUATIONSunZhizhong(孙志忠)(Depart...  相似文献   

9.
试验选用水稻品种湘早籼3号(湘3,抗病品种)和浙辐802(浙8,感病品种)为材料,至6叶期,分别用稻白叶枯病菌的弱毒株(75-1)和强毒株(76-25)在第5叶剪叶接种诱导;测定接种后12、24、48、72h第6叶的SOD活性、POD活性、MDA含量及超氧阴离子产生速率的动态变化;并于第6d在第6叶挑战接种76-25,挑战接种后15d测量病班长度。结果表明,2诱导因子均诱导2品种产生了系统获得性抗性(SAR),诱导效果浙8好于湘3,76-25好于75-1。诱导处理后,2品种上位叶中SOD活性及O·2产生速率有所降低,POD活性升高,MDA含量变化不明显,这些变化从诱导后24人开始,48h~72h的变化更大。以上结果表明诱导产生的SAR与非诱导部位的组织中活性氧代谢密切相关  相似文献   

10.
ANOTEONTHEUNIQUENESSTHEOREMFORSTEADY-STATESEMICONDUCTOREQUATIONSGuanPing(管平)(DepartmentofMathematicsandMechanics)ANOTEONTHEUN...  相似文献   

11.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

12.
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/  相似文献   

13.
《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   

14.
汉字倒说     
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   

15.
《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   

16.
王菲 《华章》2007,(12):273-273
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   

17.
钱生钱!     
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   

18.
裴水妹 《华章》2007,(11):196
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   

19.
20.
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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