Study on Spectra of La_2CaB_(10)O_(19)∶Eu~(3 ) in VUV-VIS Range

Manyboratesareexcellenthostsforrareearthlu minescence ,forexample ,nowbestredphosphorinplasmadisplaypanel (PDP )is (Y1-xGdx)BO3∶Eu[1] .Boratephosphorsdopedwithrareearthionshavebeenrichlystudiedinthepastfewdecades[2 ,3] .RecentlyWuYichengetal .[4 ] synthesizedanewbo rateLa2 CaB10 O19,whichispotentialnonlinearopticalmaterials.InthisworkweselectedLa2 CaB10 O19ashostofluminescencematerialsbecauseitprobablyisabetterhostforrareearthluminescence .Duetotherequirementofplasmadisplaypenal(PDP)…     

中国科学院广州分院、广东省科学院科技成果专利信息系统

文章阐述了建设网上科技成果信息系统的目的和必要性，结合中科院广州分院、广东省科学院成果管理的经验提出网上科技成果信息以及交易应有的功能摸块及关键技术，开发了一套实用管理系统信息模型，在实际中应用效果良好。     

Preparation and Characteristics of Optical Storage Material CaS:Ce3+, Sm3+

CaS: Ce3+, Sm3 + optical storage material was prepared by wet-method under the reducing atmosphere. Influence of sintering atmosphere on luminescence intensity was studied to get the result that active-carbon reducing atmosphere is better. XRD analysis shows that CaS crystal structure was formed at 700 ℃. The excitation spectrum is in the range of 250 ～ 500 nm with peaks at 260.2, 353.4 and 461.2 nm, the fluorescence spectrum shows a broadband spectrum with peaks at 503, 568 and 604 nm and the emission spectrum of the sample stimulated by 980 nm laser also shows a broadband spectrum with peaks at 508,565 and 600 nm. The result of spectra analysis indicates that this material can absorb and "trap" incoming light energy from ultraviolet and visible light (Information write-in), and release that stored energy in the form of green luminescence (information read-out) upon stimulation from a longer IR wavelength. The optical storage physical mechanism was also discussed.     

面向海洋渔业决策支持的信息综合协调研究

时空信息与社会行业非空间信息的综合是资源环境研究和管理的发展方向之一。该文就研究成果阐述基于信息综合的海洋渔政支持系统及其构造,系统有机综合了地理信息系统(GIS)、全球定位系统(GPS)、管理信息系统(MIS)等技术,对时空信息和社会行业信息进行有机的综合,实现对海洋渔政事务的自动协调处理,进而对渔业多源信息进行综合协调,为海上渔业指挥和调控提供决策支持,从而保障渔业生产安全和资源的可持续利用。     

安全协议认证的形式化方法研究

安全协议认证是网络安全领域中重大课题之一。形式化方法多种多样。该文首先论述了模型检测技术及其在安全协议验证中的应用,然后介绍了各种定理证明方法和定理证明工具,接着讨论其它形式化验证方法,最后论述形式化方法的一些研究方向。     

一个网上政府采购协议

随着Internet飞速发展,计算机的普遍应用,政府采购工作的网上实现越来越可行。该文在分析目前一些会话密钥分发协议利弊的基础上,利用分布式鉴别安全协议(DASS)1,2,3设计了一个在网络分布式环境中实现的,有可信第三方参与的电子政府网上采购协议。该协议基于DASS协议密钥分配的安全性。特别是协议的设计遵循了参与政府采购的公司为自身利益负责的原则。关键会话密钥由参与政府采购的公司产生。限制了可信第三方,一定程度上防止了可信第三方不可信。得到了一个有效的政府采购协议。     

网格资源管理中的经济学原理运用

网格的目标是实现对地理上广泛分布的大量异构资源进行共享。由于网格具有的异构性、分布性和动态性,传统的资源管理方法在网格环境中并不适用。此外,要吸引各类资源消费者和提供者加入网格,就必须满足他们各自的需求。将经济学原理,例如边际效用、Nash均衡等引入网格资源管理之中,能够很好地解决以上问题。该文简略地列举了近10年来在分布式系统上使用经济学模型进行资源分配的相关研究,并且对目前开展得比较好的几个网格经济学研究项目进行了分析。     

A torsional resonance mode AFM for in-plane tip surface interactions

Changing the method of tip/sample interaction leads to contact, tapping and other dynamic imaging modes in atomic force microscopy (AFM) feedback controls. A common characteristic of these feedback controls is that the primary control signals are based on flexural deflection of the cantilever probes, statically or dynamically. We introduce a new AFM mode using the torsional resonance amplitude (or phase) to control the feedback loop and maintain the tip/surface relative position through lateral interaction. The torsional resonance mode (TRmode™) provides complementary information to tapping mode for surface imaging and studies. The nature of tip/surface interaction of the TRmode facilitates phase measurements to resolve the in-plane anisotropy of materials as well as measurements of dynamic friction at nanometer scale. TRmode can image surfaces interleaved with TappingMode™ with the same probe and in the same area. In this way we are able to probe samples dynamically in both vertical and lateral dimensions with high sensitivity to local mechanical and tribological properties. The benefit of TRmode has been proven in studies of water adsorption on HOPG surface steps. TR phase data yields approximately 20 times stronger contrast than tapping phase at step edges, revealing detailed structures that cannot be resolved in tapping mode imaging. The effect of sample rotation relative to the torsional oscillation axis of the cantilever on TR phase contrast has been observed. Tip wear studies of TRmode demonstrated that the interaction forces between tip and sample could be controlled for minimum tip damage by the feedback loop.     

SLS快速成形技术中激光加工参数对制件性能的影响

以AFS--320MZ快速成形机为例，研究了基于选择性激光烧结(SLS)快速成形制造中激光功率密度、扫描速度、扫描间距、扫描方式和铺粉密度等加工参数对制件性能的影响。     

滑动轴承两种油膜边界条件的比较

本文对滑动轴承计算中两种常用的油膜边界条件进行了比较，一种是雷诺边界条件，另一种即质量守恒边界条件。对于前者，常采用负压力归零法进行计算，对于后者，大多采用Elrod算法。本文通过改变Elrod算法中的变量θ的定义，对Elrood算法进行改进，建立一新的通用方程，可自动确定动态边界，并在稳态工况下，将两种边界条件的计算结果与实验数据进行比较，发现根据质量守恒边界条件采用本文新改进的算法计算所得结果与实验数据十分吻合，同时，计算结果表明，空穴并不总是降低轴承的承载力，在稳态工况下，当空穴压力为较大的负压力时，轴承的承载能力反而有明显提高。