European intercomparison on electron spin resonance identification of irradiated foodstuffs

The results of a co-trial organized by the Community Bureau of Reference on the use of Electron Spin Resonance spectroscopy for the identification of irradiated food in 21 laboratories are presented. The trial was qualitative on beef and trout bones, sardine scales, pistachio nut shells, dried grapes, and papaya, and quantitative on poultry bones. There was no difficulty in identifying irradiated meat bones, dried grapes, and papaya. In the case of fish bones there is a need for further kinetic study on different species. Identification of irradiation in pistachio nuts is more complicated and additional research is needed before further trials. All laboratories were able to distinguish between chicken bones irradiated at 1 to 3 kGy or 7 to 10 kGy although there was a partial overlap between the results.     

微型集散系统通用过程控制软件包

本文给出一种新的基于ＭＣＳ－５１单片机集散系统通用过程控制软件包的设计原理及其实施方法。文中重点地阐述了微型集散系统的构在民，通用过程控制软件的自动生成，主要数据结构与程序结构，实现方法及关键技术等。本软件包是采用ＴＵＲＢＯＣ２．０版本和ＭＣＳ－５１泄编语言编程的，并通过了ＭＣＳ－５１组合软件的编译，形成了可用的目标码程序系统。     

全金属反射光学系统结构的有限元分析

用有限元分析方法对全金属反射光学系统在各种受力状态下的变形、应力及固有频率做了全面的分析，并给出了结构多次优化后的分析结果。     

长期不同施肥对玉米田间杂草生物多样性的影响

通过田间小区试验,研究了长期不同施肥对田间杂草总密度、优势杂草组成及生物多样性的影响。结果表明:综合施用N、P、K肥,不仅降低了田间杂草的总密度,降低了优势杂草在群落中的比重,而且有利于维持田间杂草的生物多样性;不施用N或P肥,田间杂草的总密度增大,优势杂草的比重也明显增强,但不利于维持田间杂草的生物多样性。所以,平衡施用N、P、K肥,有利于维持农田生态系统中的生物多样性,并能更好地进行杂草控制。     

Si—SiO2及其在电离辐照下的等离激元

用ＸＰＳ分析技术对抗辐射加固与非加固的Ｓｉ－ＳｉＯ２进行了电离辐照前后Ｓｉ的一级等离激元（定位于Ｂ．Ｅ．１１６．９５ｅＶ）及ＳｉＯ２一级等离激元（定位于Ｂ．Ｅ．１２２．０ｅＶ）的研究。实验结果表明：存在一个由这两种等离激元组成的界面，在电离辐射的作用下，此界面区向ＳｉＯ２表面方向展宽，界面中心向ＳｉＯ２表面方向移动；两种Ｓｉ－ＳｉＯ２界面区中的ＳｉＯ２一级等离激元的浓度在正电场中辐照均随辐照剂量的增加而增加，而非加固样品中一级等离激元浓度在正电场中随辐照剂量的变化所产生的变动快于加固样品；在同一辐照剂量下加正电样品中等离激元浓度的变化远明显于不加电样品。     

^239Puα粒子的微剂量谱和径向剂量分布

用大容积（６０ｍｍ×８０ｍｍ）的圆柱型流气式组织等效正比计数器测定了２３９Ｐｕα粒子的微剂量谱和径向剂量分布。α粒子束在无窗的情况下直接穿入正比计数器，由离子穿过而发生能量沉积的机率Ｒｂ为１。测量结果证实：沿α粒子径迹由单次事件沉积的剂量平均比能ｚ１Ｄ（Ｇｙ）与距径迹核径向距离ｂ（μｍ）之间完全符合ｚ１Ｄ＝ａｂ－２的函数关系，同时给出了求出最大径向距离（ｐｅｎｕｍｂｒａ）的方法。     

Convex relaxation for a 3D spatiotemporal segmentation model using the primal-dual method

A method based on 3D videos is proposed for multi-target segmentation and tracking with a moving viewing system. A spatiotemporal energy functional is built up to perform motion segmentation and estimation simultaneously. To overcome the limitation of the local minimum problem with the level set method, a convex relaxation method is applied to the 3D spatiotemporal segmentation model. The relaxed convex model is independent of the initial condition. A primal-dual algorithm is used to improve computational efficiency. Several indoor experiments show the validity of the proposed method.