Ambient and High-Temperature Stable Fracture Tests in Ceramics: Applications to Yttria-Partially-Stabilized Zirconia

A new technique that provides stable fracture tests in brittle ceramic materials at room and at high temperature is presented. This technique uses the crack mouth opening displacement signal from a laser extensometer to feed the servo control of a hydraulic testing machine. In this way it is possible to obtain—in addition to the fracture toughness—the fracture energy and the R -curve, in a single test.     

Processing Strategy for Producing Highly Anisotropic Silicon Nitride

Silicon nitride with a preferred orientation of large elongated grains was obtained by tape casting of raw powder slurry seeded with rodlike β-Si₃N₄ particles, followed by a gas pressure sintering under 1 MPa nitrogen pressure. The large elongated grains developed from seeds lay in planes parallel to the casting direction in a two-dimensional distribution. Increased fracture toughness (11.1 MPa·m^1/2) and bending strength (1100 MPa) were achieved in the direction perpendicular to the grains alignment compared to specimens with a random distribution of elongated grains. Morover, the specimens exhibited a high Weibull modulus of 46 due to the uniform distribution of large grains.     

String analysis by sliding positioning strategy

Discovering frequent factors from long strings is an important problem in many applications, such as biosequence mining. In classical approaches, the algorithms process a vast database of small strings. However, in this paper we analyze a small database of long strings. The main difference resides in the high number of patterns to analyze. To tackle the problem, we have developed a new algorithm for discovering frequent factors in long strings. We present an Apriori-like solution which exploits the fact that any super-pattern of a non-frequent pattern cannot be frequent. The SANSPOS algorithm does a multiple-pass, candidate generation and test approach. Multiple length patterns can be generated in a pass. This algorithm uses a new data structure to arrange nodes in a trie. A Positioning Matrix is defined as a new positioning strategy. By using Positioning Matrices, we can apply advanced prune heuristics in a trie with a minimal computational cost. The Positioning Matrices let us process strings including Short Tandem Repeats and calculate different interestingness measures efficiently. Furthermore, in our algorithm we apply parallelism to transverse different sections of the input strings concurrently, speeding up the resulting running time. The algorithm has been successfully used in natural language and biological sequence contexts.     

I3WSN: Industrial Intelligent Wireless Sensor Networks for indoor environments

Sensor Web Enablement (SWE) technologies have been successfully applied to a great variety of outdoor scenarios but, in practical terms, little effort has been applied for indoor environments, and even less in the field of industrial applications. This article presents an intelligent SWE application for an indoor and industrial scenario, with the aim of improving and increasing the levels of human safety. The base low-level architecture is built on top of wireless sensor networks (WSN) connected to a Sensor Observation Service (SOS). Higher layers in the architecture include services that make real time decisions based on the collected data. Both simulation and experimental results are presented. The paper shows the viability of our approach in terms of performance, scalability, modularity and safety.     

Towards an Environmentally Acceptable Heterogeneous Catalytic Method of Producing Adipic Acid by the Oxidation of Hydrocarbons in Air

A survey is given of the catalytic methods potentially available for the production of adipic acid by the oxidation of readily available hydrocarbon precursors under environmentally benign conditions. Encouraging results are reported using H₂O₂ as oxidant and microporous FeAlPO-5 as catalyst at moderate temperatures.     

Methanol Selective Oxidation to Formaldehyde over Iron-Molybdate Catalysts

This review deals with the important industrial reaction of formaldehyde manufacture by methanol oxidation over iron molybdate catalysts. Detailed reference is made to the used catalyst, preparation techniques (coprecipitation, sol-gel like, mechanical mixing, etc.) including unsupported and supported catalysts, promoters and characterization methods. The controversial active phase assignment (stoichiometric versus Mo rich iron molybdate) is discussed. The proposed reaction mechanisms and kinetic laws for the main and side reactions are examined. The catalyst deactivation processes are reviewed and the role of Mo excess on these processes is underlined. Finally conclusions and perspectives are presented.     

HumanTop: a multi-object tracking tabletop

In this paper, a computer vision based interactive multi-touch tabletop system called HumanTop is introduced. HumanTop implements a stereo camera vision subsystem which allows not only an accurate fingertip tracking algorithm but also a precise touch-over-the-working surface detection method. Based on a pair of visible spectra cameras, a novel synchronization circuit makes the camera caption and the image projection independent from each other, providing the minimum basis for the development of computer vision analysis based on visible spectrum cameras without any interference coming from the projector. The assembly of both cameras and the synchronization circuit is not only capable of performing an ad-hoc version of a depth camera, but it also introduces the recognition and tracking of textured planar objects, even when contents are projected over them. On the other hand HumanTop supports the tracking of sheets of paper and ID-code markers. This set of features makes the HumanTop a comprehensive, intuitive and versatile augmented tabletop that provides multitouch interaction with projective augmented reality on any flat surface. As an example to exploit all the capabilities of HumanTop, an educational application has been developed using an augmented book as a launcher to different didactic contents. A pilot study in which 28 fifth graders participated is presented. Results about efficiency, usability/satisfaction and motivation are provided. These results suggest that HumanTop is an interesting platform for the development of educational contents.     

CALIBRATION OF THE METHOD TO MEASURE BUBBLE PROPERTIES IN 2D FLUIDIZED BEDS

The purpose of the present work is to demonstrate the reliability of a digital image processing technique. A CCD (Charge Coupled Device) is used to perform an investigation on the bubble properties of a 2D gas-solid fluidized bed, and the aim of this study is to establish a criterion in order to reject all images that could not be interpreted as bubbles. This may lead to an alteration of the information obtained. The two-dimensional fluidized bed is 20 cm wide and at least 20 cm high, and the field of view of the camera is 12.54 cm wide and 12.99 cm high. In this way, bubbles could be totally or partially placed into this field of view so that a partial image of a bubble could be analyzed as a whole bubble. With this calibration, a geometric decision criterion for the rejection of nonbubble images was developed.     

The Yuma Desalting Plant

The 96 million gallon per day Yuma desalting plant is part of a complex project intended to solve a long standing water quality problem between the United States and Mexico. Designed to treat up to 129,000 acre-feet of 3200 mg/l irrigation return flows, the plant will deliver 283 mg/l product water to maintain a 115 mg/l differential between water delivered to U.S. users and to Mexico .

Design of the plant was preceded by an extensive research program to determine pretreatment requirements, membrane performance, plant capacity and equipment and instrumentation performance. Two pretreatment systems were tested. Partial lime softening followed by multi-media filtration was chosen for the final design. Nine membrane systems (both reverse osmosis and electrodialysis) were tested. Two spiral wound reverse osmosis systems were chosen as most efficient from physical and economic viewpoint, and contracts for site preparation and construction of the intakes and sedimentation basin is scheduled for award summer 1979 with construction of the main plant and installation of desalting equipment scheduled for award summer of 1980.

Based on January 1979 prices, total cost of the desalting complex is approximately $190 million (including interest during construction). The investment cost per daily gallon of installed capacity is approximately $2. per 1000 gallons of desalted water (capital amortization plus operation and maintenance) is $0.77.     

Synthesis,characterization, and metal complexation of poly(N‐phenylmaleimide‐co‐acrylic acid) and poly(N‐phenylmaleimide‐co‐acrylamide) as polychelatogens in aqueous solution

We carried out the free‐radical copolymerization of N‐phenylmaleimide with acrylic acid and acrylamide with an equimolar feed monomer ratio. We carried out the synthesis of the copolymers in dioxane at 70°C with benzoyl peroxide as the initiator and a total monomer concentration of 2.5M. The copolymer compositions were obtained by elemental analysis and ¹H‐NMR spectroscopy. The hydrophilic polymers were characterized by elemental analysis, Fourier transform infrared spectroscopy, ¹H‐NMR spectroscopy, and thermal analysis. Additionally, viscosimetric measurements of the copolymers were performed. Hydrophilic poly(N‐phenylmaleimide‐co‐acrylic acid) and poly(N‐phenylmaleimide‐co‐acrylamide) were used for the separation of a series of metal ions in the aqueous phase with the liquid‐phase polymer‐based retention method in the heterogeneous phase. The method is based on the retention of inorganic ions by the polymer in conjunction with membrane filtration and subsequent separation of low‐molecular‐mass species from the formed polymer/metal‐ion complex. The polymer could bind several metal ions, such as Cr(III), Co (II), Zn(II), Ni(II), Cu(II), Cd(II), and Fe(III) inorganic ions, in aqueous solution at pH values of 3, 5, and 7. The interaction of the inorganic ions with the hydrophilic polymer was determined as a function of pH and a filtration factor. Hydrophilic polymeric reagents with strong metal‐complexing properties were synthesized and used to separate those complexed from noncomplexed ions in the heterogeneous phase. The polymers exhibited a high retention capability at pH values of 5 and 7. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006