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11.
通过对分区链表中结点信息的研究 ,及前后结点中相关数据项比较之后 ,参照磁盘基数表中所记录的相应分区长度 ,给出了其中任一结点或整个分区链表丢失之后的修复算法 相似文献
12.
MPEG-7标准及其应用 总被引:1,自引:0,他引:1
MPEG-7是国际标准化组织即将推出的新一代多媒体国际标准,该标准主要用于对各种不同类型的多媒体信息进行标准化描述,并将该描述与所描述的内容相联系,以实现对多媒体信息快速有效的搜索.在未来的多媒体信息检索服务中,MPEG-7将发挥主导作用.本文主要从标准的目标、体系结构及应用等方面对MPEG-7进行了描述. 相似文献
13.
本文采用X射线衍射分析方法,研究了影响C_(11)A_7·CaF_2稳定性的因素,结果表明C_(11)A_7·CaF_2在1450℃以内,能够稳定存在;Mgo,K_2O对C_(11)A_7·CaF_2稳定性没有影响;Na_2O、P_2O_5和CaO能与C_(11)A_7·CaF_2发生反应、分别生成少量NC_6A_3、Ca_5F(PO_4)_3和C_3A,但在硅酸盐水泥熟料的正常煅烧制度下,反应程度较低,对C_(11)A_7·CaF_2稳定性不大.熟料中铝酸盐相存在的形式,主要取决于氟在熟料中的分布,CaF_2掺量较低,温度超过1350℃,C_(11)A_7CaF_2消失,生成C_3A;CaG_2掺量较高时,温度高达1450℃,熟料中的铝酸盐相仍为C_(11)A_7·CaF_2,而不生成C_2A. 相似文献
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15.
《科学通报(英文版)》2008,(9)
The optimizations geometries and interaction energy corrected by BSSE of the complexes between C4H4Y (Y=O, S) and CH3Li have been calculated at the B3LYP/6-311 G** and MP2/6-311 G** levels. Three complexes were obtained. Abnormally, the calculations showed that all the C10—Li14 bond lengths increased obviously but the blue-shift of C10—Li14 stretching frequency occurred after formed complexes. The calculated binding energy with basis set super-position error (BSSE) and zero-point vibrational energy corrections of complexes I―III is ?45.757, ?35.700 and ?39.107 kJ·mol?1, respectively. The analyses on the combining interaction with the atom-in-molecules theory (AIM) also showed that a relatively strong lithium bond interaction presented in furan homologues C4H4Y---LiCH3 systems. Natural bond orbital theory (NBO) analysis has been performed, and the results revealed that the com- plex I is formed with n-σ type lithium bond interaction between C4H4O and LiCH3, complex II is formed with π-s type lithium bond interaction between C4H4O and LiCH3, and complex III is formed with π-s and n-s type lithium bond interactions between C4H4S and LiCH3, respectively. 相似文献
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17.
《科学通报(英文版)》2007,(16)
The photoluminescence quenching behaviors of 5D3-7FJ and 5D4-7FJ (J = 0―6) transitions of Tb3 in YBO3:Tb under 130―290 nm excitation were systematically investigated. The results revealed that the quenching concentrations of both 5D3-7FJ and 5D4-7FJ transitions of Tb3 in YBO3:Tb were mainly de-pendent on excitation wavelength. Particularly,the quenching concentrations of 5D4-7FJ transitions of Tb3 under 130―290 nm excitation were correlated with excitation bands of YBO3:Tb. The quenching concentrations of 5D3-7FJ transitions remained at low concentration (2%) under 186―290 nm excitation and then increased gradually with energy of incoming excitation photon when excited at 130―186 nm. This dependence should be involved in their excitation mechanisms and quenching pathway in particular excitation region. 相似文献
18.
The purpose to this paper is to study the existence problem of solutions to the vector quasi-variational inequality for vector-valued functions in H-space. 相似文献
19.
通过对操作系统启动过程的深入研究,在WINDOWS98 DOS状态下,对当前大容量硬盘主引导扇区的引导过程进行了全面的剖析,导出扩展INT 13H读取大容量硬盘逻辑扇区的方法,这将对大容量硬盘的管理与维护十分有利。 相似文献
20.
Yu. Yu. Chirkov A. R. Kazarov M. A. Malatsidze A. S. Sobolev 《Cellular and molecular life sciences : CMLS》1985,41(11):1430-1432
Summary In mixed culture of Chinese hamster fibroblatst, clone 431, and transformed murine L fibroblasts, clone B-82, isoproterenol was found to protect only 431 cells against ionizing radiation. It was shown that 431 cells, in contrast to B-82 cells, possess-adrenoreceptors, and the radioprotective effect of isoproterenol can be realized only if this agent interacts with-adrenoreceptors coupled with the cAMP system. Since malignization often causes the disappearance of-adrenergic and other hormone receptors, the combined culturing and irradiation of the cells studied can be regarded as a model of the growth of malignant cells (B-82) among normal tissue cells (431 cells) under conditions of radiation therapy. A possibility of selective protection against radiation damage of normal tissue cells, with retention of the former radiosensitivity of tumor cells, is discussed. 相似文献