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21.
本论文利用半连续集值映射的插入给出具有层型结构空间的一些等价刻画.也引入了K-lower和K-upper集值映射,利用此概念给出了k-半层空间以及k-MCM的刻画. 相似文献
22.
采用动态自适应技术来根据光盘质量对主轴转速作自适应的调整,以最佳的速度读取光盘数据,有利于数据的顺利读取和保护光头组件。相应地针对光盘反射信号的质量提出一种间接评估数据质量的方法,设计了基于光盘质量的动态自适应技术,并应用于高速光盘驱动器伺服控制系统中。 相似文献
23.
方影 《上海师范大学学报(自然科学版)》1995,(2)
设Ｇ是具有ｎ个顶点的２－连通简单ＭＣＤ图，ｆ２（ｎ）表示Ｇ的边数．本文证明了当ｎ≥８时，其中ｘｍ＝ｕｍ－２ｕｍ－５，ｕｍ是Ｆｉｂｏｎａｃｃｉ数． 相似文献
24.
Lawrence LESSNER 《自然科学进展(英文版)》2004,(9)
Acquiredimmunitydeficiencysyndrome(AIDS)isoneofthemostfataldiseasesthathasspreadacrossthewholeworldsinceitfirstoccurred.Itiscausedbythehumanimmunodeficiencyvirus(HIV)[1].Mostofthechemotherapiesareaimedatkillingorhaltingthepathogen,butanewtreatmentistoreduceviralpopulationandimprovetheimmuneresponse.Thistreatmentcanboosttheimmunesystemandservetohelpthebodyfightinfectiononitsown,soitiscalledantiHIVimmunotherapy[2,3].TheaimofthisworkistofindefficientstrategiesforsuchtreatmentsusingtheDataEnv… 相似文献
25.
试析体育院校图书馆图书附件光盘的管理和使用 总被引：1，自引：0，他引：1
史桂燕 《科技情报开发与经济》2007,17(17):70-71
介绍了图书附件光盘的内容和作用,分析了体育院校光盘收藏和使用现状、管理服务模式,并提出了提高图书附件光盘利用率的方法和建议。 相似文献
26.
王家兵 《科技情报开发与经济》2007,17(30):17-18
对随书光盘检索及下载系统的架构、功能模块和数据库的设计以及采用的主要技术进行了说明。 相似文献
27.
《信阳师范学院学报(自然科学版)》2016,(3):449-452
提出并实现了一种基于STC89C54RD的RFID读卡器的设计方案,能运用在新能源电动汽车的交流充电桩上实现启动、停止控制和查询、扣费等功能.通过对应用了本设计的交流充电桩的功能测试,系统实现了预定的功能,并具有控制灵活、工作稳定、使用方便、适应环境能力强等特点. 相似文献
28.
Molecular self-assembly behavior of mono[6-O-6-(4-carboxyl-phenyl)]-β-CD in solution and solid state
FANZhi ZHAOYanli LIUYu 《科学通报(英文版)》2003,48(15):1535-1538
A novel modified cyclodextrin, mono[6-O-6-(4-carboxyl-phenyl)]-]-β-CD (1), has been synthesized by the reaction of mono[6-(p-toluenesulfonyl)]-β-CD with 4-hydroxybenzoate, and its molecular self-assembly behavior in both solution and solid state was studied by means of crystallography, NMR spectroscopy and microcalorimetry. The results indicate that the bezoic acid groups are successively penetrated intermolecularly into the adjacent β-CD cavities to form helical columnar supramolecules in the solid state. As compared with crystal, the similar self-assembly behavior of 1 in aqueous solution has also been confirmed by the ^1H ROESY spectroscopy. Thermodynamically, the formation of polymeric supramolecules by modified CD in aqueous solution is mainly driven by entropy changes. 相似文献
29.
WANG Xichao DAI Bojie CHEN Dayuan LIU Zelong LIU Weimin & DUAN Enkui State Key Laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing China Correspondence should be addressed to Duan Enkui 《科学通报(英文版)》2003,48(18):1956-1961
Pregnancy between different species is one of the key steps to interspecific somatic cell cloning. Although interspecific clone embryos have been constructed, they could not develop to birth after being transferred to recipi-ents. In order to clarify the mechanism of this phenomenon, interfamily pregnancy between golden hamste (Mesocricetus auratus) and mouse (Mus musculus) was studied. Co-culture results indicated that the adhesion ratios of golden hamster blastocysts on mouse uterine epithelia monolayer 12, 24, 48 and 72 h after co-culture were all significantly lower than those of mouse blastocysts. The outgrowth ratios of golden hamster blastocysts on mouse uterine epithelia monolayer 48, 72 h after co-culture were both significantly lower than those of mouse blastocysts (P < 0.01). Golden hamster抯 blastula could be implanted and develop to D 11 of pregnancy after being transferred to mouse uterus (the 7th day after embryo transfer). Compared to the transfer of mouse embryo to mouse uterus, the successful ratio of interfamily embryo transfer was lower and the bulk of fetus was smaller than that of intraspecific fetus. Compared to intraspecific preg-nancy of mouse, the remote decidual tissue of interfamily pregnancy on D8 is looser. At the same time, expressions of CD57 and CD 68 in remote deciduas were both higher than those in the secondary deciduas in both intraspecific and interfamily pregnancy. However, expressions of the two molecules in interfamily pregnancy were lower than those in intraspecific pregnancy. These results showed that interfam-ily pregnancy could be established between golden hamster and mouse. But the development of fetus in interfamily pregnancy was slower than that in intraspecific pregnancy. The expression difference of CD57 and CD68 indicates the difference of immunoreaction between interfamily and in-traspecific pregnancy, which may be one of the reasons lead-ing to interfamily pregnancy termination. 相似文献
30.