Effect of iron alloying in evolution of nanostructure and microstructural stability in nickel

Nanocrystalline materials show many interesting properties such as high strength and hardness due to nanosized grains and high density of interfaces. In this context, the present work reports the effect of Fe (iron) addition in Ni (nickel) on nanostructure retention during the annealing of Ni-Fe alloy (with 0, 18.5, 28.5 and 43 wt% Fe) at 450 °C for 16 h. Furthermore, effect of annealing on the deformation mechanism was investigated. The integral breadth method revealed the decrease in grain size with increase in wt% Fe in Ni. The strain rate sensitivity exponent which is a signature of operating deformation mechanism showed a higher value (0.10803) in case of Ni-18.5 wt% Fe during nanoindentation. However, Ni-0 wt% Fe, Ni-28.5 wt% Fe and Ni-43 wt% Fe were characterized by a relatively low strain rate sensitivity exponent (between 0.02069 and 0.10803). Results indicated the presence of Hall-Petch relationship up to 18.5 wt% Fe and inverse Hall-Petch relationship above 18.5 wt% Fe.     

Temperature responsive fibers with anisotropic transitional behavior

Temperature sensitive polymer hydrogels are being extensively studied because of their potential applications in the biomedical, robotics, and chemical industries. However, major hurdles in their development have been their slow response, low efficiency (swelling/deswelling ratios), and poor mechanical properties due to difficulty in processing them into mechanically strong and fine structures. Fibers made from such polymers would be highly desirable. A temperature sensitive random linear copolymer of N‐tert‐butylacrylamide (NTBA) and acrylamide (Am) was synthesized by the solution polymerization method, using regulated dosing of comonomers. Using a novel approach, a high molecular weight poly(N‐tert‐butylacrylamide‐ran‐acrylamide::27 : 73) has been converted to insoluble strong fibers with fineness of 30–50 microns by solution spinning, drawing, and subsequent crosslinking. Fibers were solution spun in acetone using a 14% copolymer solution in acetic acid with polycarboxylic acid as a crosslinker and sodium hypophosphite as a catalyst. The crosslinks were formed, subsequent to drawing, between reactive amide side groups of the acrylamide moiety of the polymer and the carboxylic acid group of the crosslinker by thermal treatment at 160°C. The transition temperatures of the crosslinked fibers were found to shift towards the lower temperature from 37°C (in linear copolymer) to 22–25°C. These engineered fibers display sharp temperature sensitivity, extremely high reversible change in dimensions (1000% in diameter and ～ 70% in length), and extremely fast response time (< 20 s for expansion and < 2 s for contraction). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 681–688, 2005     

Interface Adaptation to Novice Older Adults’ Mental Models through Concrete Metaphors

Metaphors could be used to help older adults build mental models of Information and Communication Technology (ICT) applications and services and thereby reduce the number of interaction problems, but currently, metaphors generally are not tailored to these older adults, and their construction remains vague. Inspired by concrete icons, this study proposes concrete metaphors to help novice older adults understand ICT applications and services and retains their knowledge over time. A new communication application based on concrete metaphors was designed, developed, and comparatively tested against another application based on abstract metaphors over a period of 9 days. The results indicated that the application with concrete metaphors contributed to fewer perception and cognition errors, higher usage intention, higher satisfaction, and higher preference compared to the application with abstract metaphors. In addition, the advantage of concrete metaphors was lasting, unlike concrete icons. These findings indicated that concrete metaphors could be an icebreaker or stepping stone to draw novice older adults into the information society. To further increase the impact of concrete metaphors, representing real-world operations is an essential challenge.     

Aging and annealing behavior of polycarbonate surfaces modified by direct‐current glow discharge in air

Aging and annealing a polycarbonate (PC) polymer surface treated by direct‐current (dc) glow discharge tend to revert it back to its virgin (pristine) state existing before surface modification by glow discharge. This structural recovery during aging and annealing has been studied in terms of the contact angles of test liquids and surface energy and correlated to the parameters of surface treatment such as the treatment time and power. Samples stored in hydrophobic environments such as air and treated by dc glow discharge at higher power levels show less recovery during aging than those treated at lower power levels. Similarly, a longer exposure time at a power level of 2.04 W decreases the extent of structural recovery in terms of surface energy during aging in air. At higher power levels, the higher kinetic energy of plasma species involved during dc glow discharge results in greater thickness of the damaged layer of the polymer surface, and so a PC sample exposed to dc glow discharge at a higher temperature also recovers at a slower rate during the initial phase of aging, whereas samples with surfaces modified by dc glow discharge at room temperature but annealed at a higher temperature show a relatively rapid recovery during the initial phase of aging. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Development of a Process to Measure Ozone Concentration in Processing Water at the Point of Product Application

Ozone is an effective sanitizing agent against a broad spectrum of pathogenic and spoilage organisms. Optimization of treatment applications of ozonated water is needed for increased use in the food industry. An experimental apparatus and process has been developed to digitally measure ozone concentrations in processing water at the point of product application. Two application methods were evaluated. Effects of locally available water quality and water temperature on the ozone concentrations produced were determined. Rapid measurement of ozone concentration at the product application will facilitate the investigation of improved product quality in shrimp.     

Effect of ammonia fiber expansion on the available energy content of wheat straw fed to lactating cattle and buffalo in India

The seasonal lack of availability of lush green forages can force dairy farmers in developing nations to rely on crop residues such as wheat and rice straw as the major feed source. We tested whether ammonia fiber expansion (AFEX) treatment of wheat straw would increase the energy available to Murrah buffalo and Karan-Fries cattle consuming 70% of their diet as wheat straw in India. Forty lactating animals of each species were blocked by parity and days in milk and randomly assigned to 1 of 4 treatment diets (n = 10). Treatments were a nutrient-rich diet with 0 to 20% straw (positive control; PC) and 3 high-straw diets with various levels of AFEX-treatment: (1) 70% untreated straw (no AFEX), (2) 40 to 45% untreated straw with 25 to 30% AFEX-treated straw (low AFEX), and (3) 20% untreated straw with 50% AFEX-treated straw (high AFEX). The AFEX-treated straw was pelleted. Urea was added to the no and low AFEX diets so they were isonitrogenous with the high AFEX diet. Animals were individually fed the PC diet for 14 d followed by 7 d of adaptation to treatments, full treatments for 28 to 35 d, and finally PC diets for 21 d. Compared with buffalo fed the PC diet, those fed high-straw diets consumed 29% less feed dry matter, put out 16% less milk energy, and lost 0.8 kg/d more body weight; the AFEX treatment of straw did not alter intake or milk production but greatly ameliorated the body weight loss (?1.0 kg/d for no AFEX and ?0.07 kg/d for high AFEX). In Karan-Fries cattle, high-straw diets decreased dry matter intake by 39% and milk energy by 24%, and the high AFEX diet increased intake by 42% and milk energy by 18%. The AFEX treatment increased digestibilities of organic matter, dry matter, neutral detergent fiber, acid detergent fiber, and crude protein by 6 to 13 percentage points in buffalo and 5 to 10 points in cattle. In conclusion, AFEX treatment increased the digestibility and energy availability of wheat straw for lactating buffalo and cattle and has commercial potential to improve milk production and feed efficiency when high-quality forages or grains are not available.     

Effects of activation method and mental effort on touchscreen task performance for users with and without upper extremity motor control disabilities

Universal Access in the Information Society - The rise in popularity of touchscreens supports the need for improving the usability and accessibility of the technology for users with varying...     

State of the science on the Cloud,accessibility, and the future

A state of the science conference on the Cloud, accessibility and the future was held at the University of Wisconsin–Madison on September 21 and 22, 2013. The desired outcomes of the conference were a better understanding of current and emerging issues around digital inclusion, a better understanding of where things are going, and what strategies for effectively addressing inclusion in the rapidly changing world we live in might be. Speaker presentations were pre-recorded and posted on YouTube^®. During the conference, participants discussed the issues raised in these presentations and other topics. Topics discussed included the threefold emerging threat to ICT inclusion; the approaching ICT/web/Cloud inflection point—and how it changes existing rules; Cloud-based auto-personalization as an approach to inclusion (concept, status of implementation and plans); security and privacy, risks and options, related to personalization and Cloud-based solutions; non-technical issues and realities in national and global deployment and use of technical solutions; providing the tools necessary for industry to build accessibility into next and next–next generation everyday products; globally realistic/affordable approaches to scaling, sustainability and propagation; impact of digital inclusion on national prosperity, education and literacy; need for Cloud-based solutions in government services, health, voting, education, etc., and the demands these areas may impose on solutions. The summaries for the speaker presentations and recommendations regarding research, policy and education generated during the conference are presented in this paper.