Using activity focus networks to pressure terrorist organizations

The predominant idea for using network concepts to fight terrorists centers on disabling key parts of their communication networks. Although this counternetwork strategy is clearly a sound approach, it is vulnerable to missing, incomplete, or erroneous information about the network. This paper describes a different and complementary application of network concepts to terrorist organizations. It is based on activity focus networks (AFNs), which represent the complex activity system of an organization. An activity focus is a conceptual or physical entity around which joint activity is organized. Any organization has a number of these, which are in some cases compatible and in some cases incompatible. The set of foci and their relations of compatibility and incompatibility define the AFN. A hypothetical AFN for a terrorist organization is specified and tested in a simulation called AQAS. It shows that certain activity foci, and in particular one combination, have high potential as pressure points for the activity system. The AFN approach complements the counternetwork approach by reducing the downside risk of incomplete information about the communication network, and enhancing the effectiveness of counternetwork approaches over time. Steven R. Corman is Professor in the Hugh Downs School of Human Communication at Arizona State University and Chair of the Organizational Communication Division of the International Communication Association. His research interests include communication networks and activity systems, high-resolution text and discourse analysis, and modeling and simulation of human communication systems.     

Activation and Afterheat Calculation Analysis for TBM

Safety considerations of TBM are part of the design process to ensure that the TBM do not adversely affect the safety of ITER. So accurate calculations of all radioactivity and potential harmfulness are very important for designing of device, selecting of blanket and shield material, analyzing of the safety and environment, disposing of nuclear waste and operation of the reactor.     

Activity coefficients for NaBr in aqueous ternary solutions with sodium propionate and butyrate from EMF measurements

The activity coefficients of NaBr in the NaBr–NaPropionate–H₂O and NaBr–NaButyrate–H₂O systems were determined from EMF measurements at constant total ionic strength of 0.1 0.5 1.0 1.5 2.0 and 2.5 mol-kg^–1 and at 25° C. The activity coefficients were fitted using Scatchard, Pitzer and Lim equations. Finally the excess Gibbs free energy of these mixtures were also calculated.     

La传感器在测定铝液凝固过程中La活度研究

微量稀土加入铝或铝合金中，如果加入方法、数量、时间得当，可明显改善材料的多项性能．稀土对铝及铝合金的影响规律和作用机理，已取得了一些进展，但对稀土铝合金的热力学性质，尤其是溶解态稀土的研究少有报导［‘，2］．本工作采用L即．95C。。。。FZ。。多晶作为固体电解     

反应条件对钌基氨合成催化剂性能的影响

用氨合成催化剂性能评价装置,研究了反应温度、压力、空速和氢氮比对以活性炭为载体的钌基氨合成催化剂活性的影响。研究表明,低于400℃时,随着反应温度降低,催化剂的活性急剧降低。随着压力升高,催化剂活性增大。但钌催化剂具有较高的低压活性,适宜低压合成氨。随着空速的降低,催化剂的活性明显提高。在空速和压力一定的条件下,最佳氢氮比随反应温度而异,并且当空速较高或反应温度较低时,氢氮比的变化对催化剂活性的影响更加明显。     

WOx/TiO2光催化剂的可见光催化活性机理探讨

采用磁控溅射技术在用浸渍提拉法制得的TiO2薄膜上，溅射氧化钨层,通过气相反应中光催化降解二甲苯的实验表明，WOx/TiO2薄膜具有可见光活性.通过UV-Vis吸收光谱、X射线光电子能谱（XPS）等方法对其可见光活性的机理进行探索.UV-Vis吸收光谱表明WOx,TiO2对可见光响应的范围有一定的扩展,吸收强度增加.XPS表明WOx/TiO2薄膜表面形成了明显的W杂质能级和Ti缺陷能级,这是WOx/TiO2在可见光范围有一吸收的主要原因,也是光催化剂具有可见光活性的必要条件之一，同时杂质能级的存在使半导体费米能级上移,载流子增加,光催化效率提高.     

植物生物分子的电分析化学研究——Ⅸ.多酚氧化酶活性的脉冲极谱法测定

本文用微分脉冲极谱法研究了多酚氧化酶的活性测定和酶的反应动力学。应用于马铃薯等10余种植物样品的酶活力测定,结果良好。方法简便快速,重现性好。     

磺酰脲类除草剂的三维药效团模型

磺酰脲类除草剂是七十年代末期[1，2]开发的一类超高效除草剂，杀草谱广，用量极低．它通过抑制植物体内乙酰乳酸合成酶（ALS，acetolactatesynthase）的活性[3]，破坏支链氨基酸缬氨酸、亮氨酸和异亮氨酸的合成，造成杂草的死亡．本文从三维角度出发，利用先进的三维分子设计软件APEX（ActivityPredictionExpertSystem）－3D[4]，建立破酸豚类除草剂药效团模型（biophoremodel），辅助设计、筛选活性化合物；再由药效团构造出模拟ALS酶活性位点（activesites）的空间结构，以该模拟结构为基点，以期设计出全新结构的ALS酶抑制剂的…     

Enthalpies of solution and of crystallization of lithium nitrate and of lithium nitrate trihydrate in water at 25°C

The enthalpies of crystallization of LiNO₃ and LiNO₃–3H₂O from aqueous solutions at 25°C, measured by a calorimetric method and determined from the previously published data on the concentration dependence of the enthalpy of solution, are reported. The results are compared with the values obtained from the concentration dependences of the activity coefficients and from the temperature dependences of the solubilities. The enthalpy of solution at infinite dilution and the enthalpy of hydration are given.