中国移动信令网IP化改造研究

本文结合信令IP承载优势,提出了中国移动信令网IP化改造的策略、协议架构、实施步骤及组网方案.     

国际知名高校如何培养科学传播素质

《中国科协科普人才发展规划纲要（2010—2020年）》提出,到2020年,要培养和造就一支规模适度、结构优化、素质优良的科普人才队伍,科普人才总量至少比2010年翻一番。科普人才的培养,需要在高等教育环节加强科学传播素质教育。在这方面,以美国麻省理工学院和哥伦比亚大学等为代表的国际知名高校已经开展了多年工作。本文重点介绍了美国麻省理工学院开展科学传播素质教育的情况,并在此基础上,结合中国高等教育的现状,分析了我国在高校中开展科学传播素质教育可从中汲取的经验。     

Sensitive detection of infrared photons using a high-Q microcantilever

A new approach based on microcantilevers is presented to detect infrared photons with high sensitivity. Infrared photons are measured by monitoring the amplitude change of a vibrating microcantilever under light pressure force.The irradiating light is modulated into sinusoidal and pulsed waves,and to be in-phase and anti-phase with the cantilever driving signal.A linear relationship between the amplitude change of the cantilever and the light power distributing on the cantilever was observed.Under a vacuum of 10^-4 Pa,an infrared light power of 7.4 nW was detected with the cantilever.The in-phase and anti-phase modulation to the cantilever vibration using a pulsed light results in an enhanced response of the cantilever.     

基矛电磁波的低流速测量中干扰因素分析研究

介绍了电磁渡测量流速的基本原理一多普勒效应．分析了影响低流速测量的主要干扰因素一发射泄漏干扰和旁瓣干扰。根据接收信号中发射泄漏干扰不变的特性,提出了去均值滤波的方法来消除干扰,对数据进行预处理;根据旁瓣干扰的信号特性,提出了通过频谱加窗和二次加权平均法构造频域带通滤波器来抑制干扰的方法,在仿真比较完各个窗函数的性能之后...     

一种大量程超声波液位计的实现

为解决现有的超声波液位计测量量程小,在远距离测量时误差较大的问题,提出一种大量程超声波液位计的实现方法。在不改变超声波发射功率和接收增益的基础上,通过声阻抗变换的方法提高超声波在空气介质中的传播效率,以及利用匹配滤波提高远距离液面反射回波的信噪比。经过仿真及实际测试,此种方法效果显著,能将一种频率为40 kHz超声传感器的最大量程从5 m的提高至15 m,并仍可以较好的识别出液面反射回波信号。为远距离超声波液位测量提供了一种新方法。     

Non-isothermal crystallization of polyamide 6 matrix in all-polyamide composites: crystallization kinetic, melting behavior, and crystal morphology

The difference in the melting points of polyamide 66 (PA66) fiber and polyamide 6 (PA6) film permits the preparation of all-polyamide (all-PA) composites by film-packing. Good interface performance and integrated consolidation structure in this all-PA composite are contributed to the similar chemical composition between PA66 fiber and PA6 matrix. In this paper, the non-isothermal crystallization kinetics and melting behaviors of PA6 matrix in all-PA composite are studied by differential scanning calorimetry (DSC), in which the modified Avrami equation, Ozawa model, and Mo equation combining Avrami and Ozawa equation are employed. It is found that the Mo equation exhibits great advantages in treating the non-isothermal crystallization kinetics for both neat PA6 and PA6 matrix in all-PA composite. The crystal morphologies of single PA66 fiber–PA6 composite by polarizing microscope (POM) clearly show a transcrystallinity layer of PA6 around PA66 fiber that proves a remarkable nucleation effect of PA66 fiber surface on the crystallization of PA6 matrix.     

Martensitic transition and structural modulations in Ni<Subscript>51</Subscript>Fe<Subscript>24</Subscript>Ga<Subscript>25</Subscript> ferromagnetic shape-memory alloy

The structure of near-stoichiometric Ni₅₁Fe₂₄Ga₂₅ Heusler alloy synthesized by a melt-spinning technique has been studied using transmission electron microscopy. The main phase possessed a local, well-defined L2₁ high-atomic order structure, and some fcc structural γ phase and lamellar twin structures were also present. At room temperature, a rich variety of micro-modulated domains in the parent phase was observed. The domain structures were aligned along the 〈110〉, 〈100〉, 〈211〉, and ~14° off 〈110〉 directions, resulting in a complex tweed contrast. These are possibly the precursors of martensitic transformation (MT). Below the MT temperature, Ms, the cubic parent phase transformed into modulated martensitic variants, which were composed of lamellar structures with predominantly 10 and 14 M modulated structures along the 〈110〉 directions.     

TiN/VN composites with core/shell structure for supercapacitors

TiN/VN core-shell composites are prepared by a two-step strategy involving coating of commercial TiN nanoparticles with V₂O₅·nH₂O sols followed by ammonia reduction. The highest specific capacitance of 170 F g⁻¹ is obtained when scanned at 2 mV s⁻¹ and a promising rate capacity performance is maintained at higher voltage sweep rates. These results indicate that these composites with good electronic conductivity can deliver a favorable capacity performance.     

基于Labview的微型电场传感器自动标定系统

针对微型电场传感器输出信号弱(pA量级)、噪声强等特点,设计了一种新型的传感器微弱信号检测与标定测试系统。该系统采用Labview可视化编程语言,实现传感器的采集控制和信号处理,并基于新型的相关检测和噪声抑制技术,可实现信噪比达到-60dB的信号提取,通过加载相关测试模块,可进一步测得传感器的静态及动态指标,并谱出动态响应曲线。     

水热条件下偏高岭土-矿渣基地聚合物的抗碳化性能

采用高温纯CO2水溶液加速碳化的方法,通过对不同龄期碳化试样的抗压强度和孔结构测试、渗透率测定及微观形貌分析,并结合净浆水泥石的碳化性能进行同步比较,对偏高岭土-矿渣基地聚合物的碳化性能进行了研究.结果表明:偏高岭土-矿渣基地聚合物的抗碳化能力明显优于净浆水泥石.地聚合物碳化28 d和90 d时,试样的抗压强度分别比同...