技术市场聚类和预测

本依据1993～2000年全国及各省、市、自治区技术市场成交额，用聚类分析的方法分析了我国技术市场的发展状况，进而利用最小二乘法建立了我国技术市场的预测模型。实例计算表明模型是有效的。     

华迅公司第二代射频芯片在西安问世

西安华迅微电子有限公司继2006年成功开发出我国首款GPS芯片组之后，经过一年多艰苦的技术攻关，近日成功研制出第二代射频芯片．该芯片全面覆盖GPS（L1-15）、北斗（B1-B3）、Galileo（E1-E6）、Glonass导航系统的所有频点，并且适用于第三代移动通信环境下对低功耗、抗干扰要求非常严格的手机应用．经过测试验证，该芯片具有低噪声系数、低功耗、     

中铁异象

中国中铁现身某媒体“2007年十大涉嫌报表粉饰榜单”，是一个技术与专业问题，但也不是一个技术与专业问题。     

多丝正比室的逃逸门技术

为进行空间硬X射线天文观测,研制了一个高空气球载的高压氙(Xe)多丝正比室硬X射线谱仪,采用了逃逸门技术.本文介绍逃逸门技术的原理,并描述该谱仪实现逃逸门技术的方法及实际性能.该谱仪在87年高空气球飞行观测中获得了有效的实验数据.     

企业声誉在电子商务消费者信任建立过程的作用机制

声誉是企业的一项重要无形资产,能够增进企业对消费者的吸引力。本文从消费者视野探索企业声誉在电子商务消费者信任建立过程的作用机制。将感知的安全性引入技术接受模型,建立了理论模型及假设,并应用结构方程模型分析软件进行了检验。结果表明,企业声誉通过消费者感知的安全性、有用性和易用性正向影响消费者信任,消费者感知的安全性、易用性也通过感知的有用性影响消费者信任。     

Typical Microstructures of Chinese Medicines with X-Ray Microscopy in Phase Contrast

Due to the low absorption contrast of plant tissues, traditional x-ray radiography has not been included in the microscopic techniques used in the identification of traditional Chinese medicines （TCMs）. With the development of x-ray phase contrast imaging （XPCI） in recent years, weakly absorbing materials could also be imaged by x- rays. Here we investigate microstructures of TCMs utilizing XPCI based on a nano-focus x-ray tube. The results demonstrated that XPCI is capable of revealing the microstructures of TCMs used as judging criteria in the identification of TCMs. The major advantages of the new method are nondestructivity, no special demand for sample preparation and suitability for thick samples.     

Varying Track Etch Rates along the Fission Fragments＇ Trajectories in CR-39 Detectors

We determine the behavior of track etch rate VT along the tracks in CR-39 detectors exposed to fission fragments from ^252Cf source. CR-39 detectors are etched at 70℃ in different concentrations of Na2COa-mixed 6M NaOH solutions for different etching time intervals of 5-10min starting from 15 min up to 210min. Two values of track etch rate are determined along the fission fragment trajectories. The variation in VT is correlated with the energy loss rate of the fission fragment in the detector material.