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Device Capable (device + capable)
Selected AbstractsELECTRICAL CONDUCTIVITY OF HEATED CORNSTARCH,WATER MIXTURESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 6 2009EDUARDO MORALES-SANCHEZ ABSTRACT Electrical conductivity (EC) of cornstarch,water mixtures in the range 10:90 to 70:30 (w/w) was studied as a function of temperature. An external resistive heating system equipped with an electronic device capable of monitoring EC in real time was used and EC of the mixtures was measured while heated at a rate of 5C/min. Results showed that EC went through four different temperature-dependent stages (A, B, C and D). Stage B (41C to 64C) showed a lower EC increasing rate when compared with that of Stage A (from 25C to 41C), probably as a result of starch granule swelling. In Stage C (64C to 78C), EC behavior was found to be dependent on water content. When water content was more than 50%, the value for EC increased. On the other side, EC decreased when water content was less than 50%. Stage C was related to starch gelatinization, according to differential scanning calorimetry results obtained in this study. In Stage D (78C to 92C), a steady increase in EC was observed, probably as a result of the total solubilization of starch in water. It was concluded that Stage C in EC graphs corresponded to cornstarch gelatinization, so it might be possible to use EC monitoring as an alternative technique to measure cornstarch thermal characteristics with different contents of water. PRACTICAL APPLICATIONS Electrical conductivity can be used as an adequate technique to monitor gelatinization, granule swelling and phase change of starch as a function of temperature in corn starch,water mixtures with a wide range of water contents. With this technique, it is also possible to calculate important thermal parameters, such as the beginning and end of the gelatinization and the energy activation for the heating process of cornstarch. This can lead to a better design and control of important industrial corn processes such as alkaline cooking. [source] Crystallizing proteins on the basis of their precipitation diagram determined using a microfluidic formulatorJOURNAL OF SYNCHROTRON RADIATION, Issue 6 2005Morten O. A. Sommer Crystallization of proteins from a purified protein solution remains a bottleneck in the structure determination pipeline. In this paper the crystallization problem is addressed using a microfluidic device capable of determining detailed protein precipitation diagrams using less than 10,µL of protein sample. Based on the experimentally determined protein phase behavior, a crystallization screen can be designed to accommodate the physical chemistry of the particular protein target. Such a tailor-made crystallization screen has a high probability of yielding crystallization hits. The approach is applied to two different proteins: the calcium pump (SERCA), an eukaryotic integral membrane protein, and UMP kinase, a prokaryotic soluble kinase. Protein phase behavior is mapped for both proteins and tailor-made crystallization screens are designed for the two proteins resulting in about 50% crystallization probability per experiment. This illustrates the power of using microfluidic devices for detailed characterization of protein phase behavior prior to crystallization trials. [source] A simple device for the evaluation of the UV radiation indexMETEOROLOGICAL APPLICATIONS, Issue 2 2003Giuseppe Rocco Casale The solar ultraviolet radiation (UV) flux density at the earth's surface depends on the incoming solar energy and the transmission properties of the atmosphere. UV radiation is strongly absorbed by ozone in the spectral range 200,310 nm, while the attenuation is increasingly weaker at longer wavelengths. Following the discovery of the Antarctic ozone hole in 1985, the risk of a possible UV increase at ground level, due to the observed stratospheric ozone depletion, has heightened the interest within the scientific community given the potentially harmful effects on terrestrial and aquatic ecosystems. Spectroradiometers, broad-band meters and dosimeters may be used for measurements of solar UV. In addition, radiation transfer models can be used to quantify UV irradiances at various times and locations, provided that the extraterrestrial solar radiation and the state of the atmosphere are known. Information about UV radiation at the earth's surface is given by the ultraviolet index ,UVI', which is defined as the effective integrated irradiance (280,400 nm) weighted by the erythemal action spectrum. The UV Index is widely used by many international weather services as an indicator of UV levels at the earth's surface providing public awareness of the effects of prolonged exposure to the sun's rays. The aim of this paper is to present a device capable of estimating the UV Index. This device is a compact disc, used as a sundial, and is based on modelled UV irradiances derived from the STAR radiative transfer model (System for Transfer of Atmospheric Radiation). The device was tested in an urban setting under clear sky conditions. Copyright © 2003 Royal Meteorological Society [source] Optical design and performance of a novel multifunction optical deviceMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 8 2008Q. H. Chen Abstract This letter presents a novel MEMS-based multifunction-integrated optical device capable of performing as variable optical power splitter (VOPS), optical switch (OS), and variable optical attenuator (VOA). The device manipulates the light with a binary-slope mirror driven by compound electrostatic actuator. The optical models for splitting and attenuating are investigated, respectively. Ball-lensed fibers are assembled with the device to achieve high coupling efficiency in this work. Measurements reveal that the excess loss of the device is less than 3 dB, and the controllable attenuation range is up to 39 dB. Moreover, polarization-dependent loss is less than 0.7 dB. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2185,2189, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23603 [source] Inactivation of Bacteria by the Plasma PencilPLASMA PROCESSES AND POLYMERS, Issue 6-7 2006Mounir Laroussi Abstract Summary: A device capable of generating a relatively long cold plasma plume has recently been developed. The advantages of this device are: plasma controllability and stability, room temperature and atmospheric pressure operation, and low power consumption. These features are what is required from a plasma source to be used reliably in material processing applications, including the biomedical applications. In this communication we describe the device and we present evidence that it can be used successfully to inactivate Escherechia coli in a targeted fashion. More recent experiments have shown that this device inactivates other bacteria also, but these will be reported in the future. Photograph of a He plasma plume launched out of the plasma pencil. [source] Monitoring individual compliance in glaucoma patients used to topical therapyACTA OPHTHALMOLOGICA, Issue 2007AM BRON Purpose: Individual compliance with Brimonidine eye drops was studied in glaucoma patients and ocular hypertensives. Methods: Conventional Brimonidine vials were equipped with a microprocessor-controlled monitoring device capable to record date and time of each eye drop application including ambient temperature. After written informed consent, glaucoma and ocular hypertensive patients used to eye drop therapy were randomly assigned to Brimonidine therapy b.i.d or t.i.d daily for 4 weeks. Results: Twenty six males and fourteen females aged 69 ± 11 years [42-89] were enrolled in this study. According to the monitoring devices all patients were non-compliant with regard to total dose and coverage. Electronic records revealed a mean of 1.5 (range: 1.1-2.0) applications per day for patients assigned to Brimonidine 2x daily with a mean treatment interval of 16.8 hours (range: 12.1-22.2 h). Patients on Brimonidine 3x daily showed a mean rate of 1.9 (range: 1.8-2.7) applications per day and a mean treatment interval of 11.9 h (range: 9.1-13.9 h). One patient discontinued therapy after day 7 (12 applications) and one after day 1 (1 application only). No difference was observed between IOP at baseline and after one month (p=0.16). Conclusions: The monitoring devices permit to detect individual non-compliance with regard to missed doses, non-treatment intervals. Our data confirm the need for larger studies on individual compliance with topical ocular therapy in glaucoma. [source] Drag reduction by flow separation control on a car after bodyINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 11 2009Mathieu Rouméas Abstract New development constraints prompted by new pollutant emissions and fuel consumption standards (Corporate Average Economy Fuel) require that automobile manufacturers develop new flow control devices capable of reducing the aerodynamic drag of motor vehicles. The solutions envisaged must have a negligible impact on the vehicle geometry. In this context, flow control by continuous suction is seen as a promising alternative. The control configurations identified during a previous 2D numerical analysis are adapted for this purpose and are tested on a 3D geometry. A local suction system located on the upper part of the rear window is capable of eliminating the rear window separation on simplified fastback car geometry. Aerodynamic drag reductions close to 17% have been obtained. Copyright © 2008 John Wiley & Sons, Ltd. [source] Ion-Triggered Multistate Molecular Switching Device Based on Regioselective Coordination-Controlled Ion BindingCHEMISTRY - A EUROPEAN JOURNAL, Issue 23 2005Anne Petitjean Dr. Abstract Molecular devices capable of accessing different controlled conformational states, while optically signaling the occupied state, are attractive tools for nanotechnology since they relate to both areas of molecular mechanical devices and logic gates. We report here a simple molecular system that allows access to four distinct conformational and optical states. It is based on the regioselective complexation of metal ions to a heterocyclic ligand triad, which is dictated by the accessible coordination geometry and electrostatic properties of two distinct binding subunits. Thus, local conformational switching is brought about by tetrahedral coordination (of CuI) or octahedral coordination (of M2+ ions) to bidentate and tridentate binding subunits, respectively. The shape modifications undergone represent an ion-controlled nanomechanical device. They give controlled access to four different states that display different physico-chemical (e.g. optical) properties and provide a basis for logic gate operations. [source] | |||||||||||||