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991.
Large-ring cyclodextrins (LR-CD) are cyclic -1,4-glucanscomposed of nine to more than several hundred glucopyranose units. The firstdefinitive evidence for the existence of LR-CD with a degree of polymerization between 9and 13 was reported in 1965. That LR-CD study did not reveal anything that attracted attention. LR-CD with a degree of polymerization between 9 and 31 were isolated andcharacterized during the past decade, and so began to attract considerable attention. This mini-review summarizes the findings of LR-CD with regard to the potentialfor host-guest interactions and corresponding applications.  相似文献   
992.
P2P文件污染及其检测方法研究   总被引:1,自引:0,他引:1  
为了更好地理解对等网络中的文件污染,介绍了文件污染的背景和分类,分析了文件污染的传播途径及检测方法,描述了用户行为对污染的影响,结合节点信誉系统和对象信誉系统阐述了反污染机制,并对各种方案进行了比较。  相似文献   
993.
The association constants (Ka) for the inclusion complexation of -cyclodextrin (-CD) with 72 mono- and 1,4-disubstituted benzenes were predicted successfully by an artificial neural network (ANN) with molar refraction (Rm) and hydrophobic constant () as input parameters, which reflect the volume and hydrophobicity of the substituents respectively. The predictions strongly suggested that the inclusion complexation of -CD with guest molecules was mainly driven by van der Waals forces and hydrophobic interactions  相似文献   
994.
陈俊亮 《电信科学》1996,12(1):17-20
本文简略回顾了智能网的发展历史,给出定义,在通信网中的地位及其功能构成。通过增值业务的发展分析,展望其未来的可能技术方向。  相似文献   
995.
NEAX61Σ程控交换机是NEC公司最新开发的换代产品,本文对该产品的结构、特点、性能、指标,以及它的网络接口和信令等做了全面的介绍,是了解NEAX61Σ系统的重要资料。  相似文献   
996.
We present the concept of integrated processing to combine intuitive processing of neural networks with logical processing of the conventional digital computer. We investigate a way to embody the concept in the neural network system by introducing external constraints in terms of external input. The effect of the external input is analyzed using the generalized projection method. The concept of integrated processing is applied to an image associative memory system, and the system is optically implemented for high-speed parallel processing incorporating it with the computer. The experimental result is presented to illustrate the effectiveness of the external input to control the output of the image associative memory.  相似文献   
997.
UMTS全IP无线网络的移动性管理   总被引:1,自引:1,他引:0  
文章讨论了3GPP UMTS全IP无线网络中的两种运行模式:传输模式和本机模式,3个不同层次移动性支持:接入移动性、宽域移动性和微移动性.对基于路由和基于隧道两种移动性管理协议进行了比较,并介绍了基于多协议标志交换(MPLS)的分级移动性管理方案,该方案利用标志边界移动性代理的增强MPLS路由器,使网络具有灵活性、可升级性和无隙缝移动性.  相似文献   
998.
In the 2nd Science and Technology Basic Plan (2001–2005), the area of nanotechnology and materials is designated one of the four prioritized areas in funding. Following this plan, Ministry of Education, Culture, Sports, Science and Technology (MEXT) and Ministry of Economy, Trade and Industries (METI), the main funding ministries, and their organizations, Japan Society for the Promotion of Science (JSPS), Japan Science and Technology Agency (JST), National Institute for Materials Science (NIMS), RIKEN, New Energy and Industrial Technology Organization (NEDO), and National Institute of Advanced Industrial Science and Technology (AIST) promotes their research programs. Besides, in order to promote interdisciplinary, interorganizational, and international collaboration of researchers, Nanotechnology Support Project (NSP) was started by MEXT in 2002. The project has two missions: informational support and common use facility support. Nanotechnology Researchers Network Center of Japan is responsible for informational support, and 14 universities and national research institutes are responsible for common use facility support.  相似文献   
999.
A complex of 5,7-dioxo-1,4,8,11-tetraazacyclotetradecane (dioxocyclam) and 2,6-dihydoxyanthraquinone (anthraflavic acid) has been obtained. The complex (crystals grown from water-ethanol solution) has a stoichiometry dioxocyclam-anthraflavic acid 1:1:5. C31H32N4O8, chemical formula weight 588.61, triclinic, P – 1, a = 10.542(3) Å, b = 11.936(2) Å, c = 12.206(2) Å, = 104.00(1)°, = 92.68(2)°, = 103.64(2)°, V = 1439.4 (5) Å3, Z = 2, Dx = 1.358 g cm–3. Only one of the two amine N-atoms of the macrocycle is protonated due to very weak acidic properties of 2,6-dihydoxyanthraquinone. Due to the rather poor quality of the crystals and structure refinement, reliable determination of H-bonds is complicated. Nevertheless, several types of H-bonding responsible for the formation of a developed supramolecular network can be suggested: between the protonated amino groups and macrocycle's C=O moieties; between non-protonated amino groups and macrocycle's C=O moieties; between protonated and non-protonated amino groups; between the amide NH and C=O groups of anthraflavic acid; and between protonated and deprotonated hydroxy groups of the acid. Two types of anthraflavic components can be distinguished in the lattice: those having a parallel orientation with respect to the macrocyclic fragments and forming hydrogen bonds with the latter, and those lying in an approximately perpendicular plane and not involved in H-bonding with the macrocycles.  相似文献   
1000.
付仕明  黄俊伟 《通信技术》2007,40(11):186-188
文中从接入点结合Bluetooth TD-SCDMA手机出发,设计了一种无线局域网应用方案.从功能上讲相当于通过Bluetooth建立无线微微网,并以TD-SCDMA手机为主机平台建立,充分利用了TD-SCDMA网络的高传输速率和高覆盖率,实现微微网内所有从设备都能通过TD-SCDMA手机实现高速无线上网.首先,文中论述了TD-SCDMA手机和Bluetooth技术,然后在这基础上提出了应用方案.最后,阐述了方案的关键技术.  相似文献   
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