Hydrothermal synthesis of nanostructured TiO2 particles and characterization of their photocatalytic antimicrobial activity

Nanostructured titania particles were synthesized by using hydrothermal processing and the photocatalytic antimicrobial activities were characterized. Both sol-gel synthesized and commercial TiO2 (anatase) samples were processed with two step hydrothermal treatments, under alkaline and neutral conditions. Scanning Electron Microscope (SEM) images showed that alkaline treatment yields nanofibers and lamellar structured particles from the commercial anatase and sol-gel synthesized samples respectively. Further treatment of nanofibers and nanostructured lamellar particles with distilled water results with crystal growth and the formation of nano structured bipyramidal crystalline particles. The photocatalytic antimicrobial activities of the samples were determined against Escherichia coil under irradiation. It was observed that the samples treated under alkaline conditions have improved activity than the original anatase samples. Limited activity and resulting time lag in bacterial inactivation were observed for hydrothermally treated samples with distilled water. However, a post treatment comprising the UV irradiation in aqueous conditions enhanced the photocatalytic activity.     

Borusan音乐和艺术中心

位于伊斯坦布尔历史文化区贝尤鲁的新Borusan音乐与艺术中心是一个集展览、活动、排练及多种文化培训项目的多功能建筑。新的文化中心象征着发生在整个贝尤鲁的文化与艺术复兴潮流,同时保留了     

Individual differences in working memory capacity predict retrieval-induced forgetting.

Selectively retrieving a subset of previously studied information enhances memory for the retrieved information but causes forgetting of related, nonretrieved information. Such retrieval-induced forgetting (RIF) has often been attributed to inhibitory executive-control processes that supposedly suppress the nonretrieved items' memory representation. Here, we examined the role of working memory capacity (WMC) in young adults' RIF. WMC was assessed by means of the operation span task. Results revealed a positive relationship between WMC and RIF, with high-WMC individuals showing more RIF than low-WMC individuals. In contrast, individuals showed enhanced memory for retrieved information regardless of WMC. The results are consistent with previous individual-differences work that suggests a close link between WMC and inhibitory efficiency. In particular, the finding supports the inhibitory executive-control account of RIF. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fiber orientation in multilayer tubes processed by a conical extruder

A new extruder design has been developed for the coextrusion of two-layer annular sections. The extruder consists of a conical stator-rotor-stator assembly, which performs extrusion from each side of the rotor. Flow within this assembly is fully three-dimensional, with helicoidal streamlines in the vicinity of the rotor and the die entry region. Fiber orientation is created in a circumferential direction by these helicoidal streamlines; close to the inner and outer surfaces of the tube, the fibers are parallel to the main extrusion direction, whereas in the mid-thickness, they are oriented in the circumferential direction. It is demonstrated that the amount of orientation depends on rotor speed and die design. When using a short die and high rotor speed, an increased fraction of fibers are oriented in the circumferential direction. Polym. Compos. 25:331–341, 2004. © 2004 Society of Plastics Engineers.     

Introducing HyPeak: An international network on hydropeaking research,practice, and policy

An increase in the demand for renewable energy is driving hydropower development and its integration with variable renewable energy sources. When hydropower is produced flexibly from hydropower plants, it causes rapid and frequent artificial flow fluctuations in rivers, a phenomenon known as hydropeaking. Hydropeaking and associated hydrological alterations cause multiple impacts on riverine habitats with cascading effects on ecosystem functioning and structure. Given the significance of its ecological and socio-economic implications, mitigation of hydropeaking requires an inter- and transdisciplinary approach. An interdisciplinary network called HyPeak has been conceived to enrich international research initiatives and support hydropower planning and policy. HyPeak has been founded based on exchange and networking activities linking scientists from several countries where hydropeaking has been widespread for decades and numerous studies dedicated to the topic have been carried out. HyPeak aims to integrate members from other countries and continents in which hydropower production plays a relevant role, and grow to be a reference group that provides expert advice on the topic to policy-makers, as well as researchers, stakeholders, and practitioners in the field of hydropeaking.