Effect of Cr addition on room temperature hydrogenation of TiFe alloys

This paper discusses the effect of AB₂ (Ti(Cr, Fe)₂) phase on the hydrogenation properties of a Ti–Fe–Cr alloy system. Five Ti–Fe–Cr based alloys were fabricated by varying the Cr content. The microstructural analysis results revealed that the fraction of the Ti(Cr, Fe)₂ phase increased with the increasing Cr content. The first hydrogenation test results indicated that all the alloys could absorb a significant amount of hydrogen at room temperature (30 °C) without a separate activation process. This behavior improved when the Ti(Cr, Fe)₂ phase existed in the AB phase; the kinetics of the first hydrogenation tended to increase with the fraction of Ti(Cr, Fe)₂ phase. The enhancement in the first hydrogenation kinetics of the Ti–Fe–Cr based alloys was attributed to the synergetic effect of the interface between the AB and Ti(Cr, Fe)₂ phases and the inherent fast hydrogenation of the Ti(Cr, Fe)₂ phase. However, the total hydrogen storage capacity decreased when the fraction of Ti(Cr, Fe)₂ phase increased.     

Discrimination of palm olein oil and palm stearin oil mixtures using a mass spectrometry based electronic nose

To discriminate mixing ratios for mixtures of palm olein oil and palm stearin oil, an electronic nose based on mass spectrometer (MS-electronic nose) and GC were used. The intensities of each fragment from the palm olein oil and palm stearin oil by the MS-electronic nose were used for discriminant function analysis (DFA). When palm olein oil is mixed with palm stearin oil, more than 3% of stearin oil can be estimated by DFA. The obtained data were used for DFA. DFA plot indicated a significant separation of pure palm olein oil and palm stearin oil. The added concentration of palm stearin oil to palm olein oil was highly correlated with the first discriminant function score (DF1). When palm stearin oil was added to palm olein oil, it was possible to predict the following equation; DF1= −0.112×(conc. of palm stearin oil)+0.416 (r²=0.95). When palm stearin oil was added to palm olein oil, peak area of GC was correlated to DF1 by MS-electronic nose with ratio of palm olein oil vs palm stearin oil. The MS-electronic nose system could be used as an efficient method for the authentication of oil.     

Abietane diterpenoids of Rosmarinus officinalis and their diacylglycerol acyltransferase-inhibitory activity

Inhibition of acyl CoA:diacylglycerol acyltransferase (DGAT) has been proposed as one of the drug targets for treating obesity and type 2 diabetes. Bioassay-guided fractionation of the MeOH-soluble extract of Rosmarinus officinalis yielded two new diacylglycerol acyltransferase (DGAT) inhibitory-abietane diterpenoids, 7β-hydroxy-20-deoxo-rosmaquinone (1) and 7β-methoxy-20-deoxo-rosmanol (2), along with six known components, carnosol (3), 7α-methoxyrosmanol (4), 7β-methoxyrosmanol (5), 12-methoxy-canosic acid (6), rosmanol (7), and rosmadial (8). Compounds 1–8 inhibited DGAT1 activity, with the IC₅₀ values ranging from 39.5 ± 0.6 to 144.2 ± 3.1 μM. In particular, carnosol (3), which is one of the major compounds of MeOH-soluble extract of R. officinalis exhibits inhibition of de novo intracellular triacylglycerol synthesis in human hepatocyte HepG2 cells.     

Development of a Traceable Fire Alarm System Based on the Conventional Fire Alarm System

Many countries use conventional fire alarm control panels (FACPs) and conventional detectors as fire alarm systems (FASs) because of economic advantages. This study analyzes several problems with conventional FASs and describes an advanced FAS, the traceable FAS, that we developed to solve these problems. The traceable FAS can trace the exact location of a fire, can detect multiple fires that occur simultaneously, and can be used with conventional detectors without disrupting the other detectors operation. The traceable FAS consists of a traceable FACP based on the conventional FACP and a traceable heat detector based on the rate-of-rise spot-type conventional heat detector. The new system offers traceability in addition to all the features of the conventional FAS. The traceable FACP has 40 zones; one zone can connect up to 20 traceable heat detectors. Thus, this FACP can connect up to 800 traceable heat detectors, all of which can detect and trace exact fire locations in sequence. Furthermore, the traceable FACP can be used with both traceable heat detectors and conventional heat detectors in the same zone. Even if one detector (either traceable heat detector or conventional heat detector) detects a fire first, other traceable heat detectors in the same zone can also detect it and display the results on the traceable FACP. Prototypes of the traceable FACP and traceable heat detector (rate-of-rise spot-type) have officially received model approvals for use in South Korea. Conventional FASs can be upgraded to traceable FASs simply by changing to the traceable FACP and traceable heat detectors, without any rewiring.     

Adaptive interactions in shared virtual environments for heterogeneous devices

In this research, we propose a method to adapt the interfaces and interaction processes of heterogeneous devices. The proposed method models the interaction capability of the devices. The interaction is modeled by categorizing elementary actions and measuring its effect in semantic behaviors. With this model, an interaction process can be modified to a given device by changing sequence of elementary actions for each behavior. In the pilot test, we showed the possibility of interaction adaptation for different situations. With the proposed adaptation mechanism, interface and interaction can be modeled for the device independently and can be transferred over different interaction environments. Copyright © 2010 John Wiley & Sons, Ltd.     

Numerical study on flow and heat transfer characteristics of air-jet cooling system

Journal of Mechanical Science and Technology - The present study aims to numerically analyze the cooling characteristics of the air-jet array in designing more efficient air-cooling system. Heat...     

Luminescent properties of Pr doped ZrSiO4 phosphors

Mixtures of ZrO₂, SiO₂, Pr₂O₃, and H₃BO₃ were fired at the temperature of 1150–1350 °C under H₂ atmosphere. A single phase ZrSiO₄:Pr phosphors could be achieved at the firing temperature above 1150 °C. Crystallinity and PL properties strongly depended on the flux amounts, firing temperature, and dopant concentrations. ZrSiO₄:Pr phosphors showed a strong red emission at 615 nm and a weak red emission at 622 nm with an excitation wavelength of 295 and 450 nm, respectively. Two sets of the emission bands and excitation spectra originated from Pr³⁺ ions at Zr and Si sites, respectively.     

Drug-releasing kinetics of MPEG/PLLA block copolymer micelles with different PLLA block lengths

Copolymers of poly(L -lactic acid) and methoxy end-capped poly(ethylene glycol) were synthesized, and their structure and physical properties were characterized. Micellar structures were formed in aqueous media because of the amphiphilic nature of the copolymers, and their sizes were measured with both dynamic light scattering equipment and scanning electron microscopy. Indomethacin was loaded into the copolymer micelles, and its releasing behavior was monitored. The drug-releasing mechanism was determined from an investigation of the biodegradation kinetics of the copolymer micelles. The releasing mechanism was governed by diffusion rather than a biodegradation process. We adapted a model based on Fick's diffusion theory to describe the overall releasing behavior with the extraction of the diffusion coefficient. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2599–2605, 2001