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基于Radius协议的多媒体通信网用户认证系统 总被引:1,自引:0,他引:1
目前,邮电部正在组建中国公众多媒体通信网,该网是为满足当前社会各界对多媒体通信日益增长的需要和适应未来宽带多媒体网过渡,由中国电信在公众电信网基础上,利用Internet/Intranet技术组织、建设的,可统一管理的,以中文服务、面向国内为主,提供多媒体通信服务的公众业务网。中国公众多媒体通信网, 相似文献
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以Mn掺杂的ZnS(Mn-ZnS)室温磷光(RTP)量子点的磷光为信号,以2-溴甲基苯硼酸与4,4ˊ-联吡啶为原料合成的硼酸基联吡啶盐(BBV)为受体,带负电的量子点与带正电BBV通过静电作用形成Mn-ZnS/BBV纳米复合材料,Mn-ZnS量子点磷光猝灭,加入果糖,BBV与果糖形成阴离子硼酸酯,降低了对量子点猝灭效率,RTP恢复.考察了时间、pH值对Mn掺杂的ZnS QDs/BBV纳米复合材料磷光强度的影响,在最优条件下,此传感器检测果糖的线性范围为0.05~1.00 mmol/L,检出限为0.01 mmol/L,相关系数r为0.99.本磷光分析法简便快速、灵敏度高,有望应用于食品、医药行业中果糖含量的检测分析. 相似文献
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目前我国软件产业规模小、人员分散、抗风险能力低下,处于发展的初级阶段,但人才优势与发展册时并存。面对挑战,必须有相应的大举措,如联合、重组、兼并,如多方筹资、加大投入,如强化管理、政策扶植等等,最终做出正确选择。 相似文献
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为实现红外图像坏元修正FPGA(field programmable gate array)的快速验证,提高测试覆盖性,设计了基于SV-DPI(SystemVerilog-direct programming interface)的FPGA自动化验证平台。采用DPI(direct programming interface)编程接口技术,实现了SystemVerilog平台调用C++编程语言,构建了针对红外图像坏元数据的生成和检测修正模型,建立了两种语言在事务级(transaction level)模型的通信。结果表明相对于传统验证方法,该平台结构简单,可以快速实现激励产生、参考模型构建、测试结果自动比对等功能,实现了红外图像坏元检测与修正FPGA的自动化测试,功能覆盖率达到100%,有效缩短FPGA测试平台搭建和调试周期,提高了测试效率和测试质量。 相似文献
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Nasicon materials(sodium superionic conductors) such as Li_(1.5)Al_(0.5)Ge_(1.5)(PO_4)_3(LAGP) and Li_(1.4)Al_(0.4)Ti_(1.6)(PO_4)_3(LATP) have been considered as important solid electrolytes due to their high ionic conductivity and chemical stability.Compared to LAGP, LATP has higher bulk conductivity around 10~(-3) S/cm at room temperature; however, the apparent grain boundary conductivity is almost two orders of magnitude lower than the bulk, while LAGP has similar bulk and grain boundary conductivity around the order of 10~(-4) S/cm. To make full use of the advantages of the two electrolytes, pure phase Li_(1.5)Al_(0.5)Ge_(1.5)(PO_4)_3 and Li_(1.4)Al_(0.4)Ti_(1.6)(PO_4)_3 were synthesized through solid state reaction, a series of composite electrolytes consisting of LAGP and LATP with different weight ratios were designed. XRD and variable temperature AC impedance spectra were carried out to clarify the crystal structure and the ion transport properties of the composite electrolytes. The results indicate that the composite electrolyte with the LATP/LAGP weight ratio of 80:20 achieved the highest bulk conductivity which shall be due to the formation of solid solution phase Li1.42 Al0.42 Ge0.3 Ti1.28(PO4)3, while the highest grain boundary conductivity appeared at the LATP/LAGP weight ratio of 20:80 which may be due to the excellent interfacial phase between Li_(1+x)Al_xGe_yTi_(2-x-y)(PO_4)_3/LATP. All the composite electrolytes demonstrated higher total conductivity than the pure LAGP and LATP, which highlights the importance of heterogeneous interface on regulating the ion transport properties. 相似文献
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采用聚乙烯醇对碳纳米管表面进行改性,通过化学沉淀法将Al(OH)3均匀沉积在碳纳米管表面,然后在氮气气氛下于500 ℃煅烧2 h,制备出氧化铝/碳纳米管复合材料。采用TEM、TG、DTA、XRD、IR、氮吸附脱附(比表面积及孔结构分析)等对氧化铝/碳纳米管复合材料进行表征,结果表明:未经聚乙烯醇改性的碳纳米管,氧化铝与碳纳米管相互分离;经聚乙烯醇改性的碳纳米管,氧化铝与碳纳米管结合良好。经聚乙烯醇改性的碳纳米管表面均匀覆盖一层聚乙烯醇膜,通过聚乙烯醇的吸附作用, Al(OH)3沉积在碳纳米管表面形成一层连续的覆盖层。 相似文献
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提出一种基于氧化石墨烯(GO)微纳光纤的生物传感器,将其用于狂犬病毒(RV)的免疫检测研究。首先,将标准单模光纤通过熔接机放电形成双锥形光纤,再对双锥形光纤进行熔融拉锥制作出高灵敏度的微纳光纤。然后,在微纳光纤表面修饰GO,并将RV抗原固定于该传感器表面,用于对RV抗体的特异性检测实验。实验结果表明:该生物传感器对RV抗体的检测范围为200 fg/mL~1 ng/mL,检测极限(LOD)约为225.56 fg/mL,其检测灵敏度约为1.099 nm/log(mg·mL-1),解离系数约为2.92×10-11 M;当用于不同的抗体溶液样本和RV阳性血清的对照检测及临床检测时,该免疫传感器对前者的响应非常微弱,而对后者有明显的响应,说明其对RV抗体具有良好的特异性。基于GO修饰微纳光纤的免疫传感器具有制作简单、微纳尺寸、灵敏度高、成本低等优点。 相似文献