Enzymatic synthesis of monosaccharide fatty acid esters and their comparison with conventional products

5-O-Acyl-1,2-O-isopropylidene-D-xylofuranose and 6-O-acyl1,2∶3,4-di-O-isopropylidene-D-galactopyranose were enzymatically prepared from the corresponding monosaccharide acetals and commercial (crude) fatty acid mixtures. Subsequent acid-catalyzed hydrolysis of the isopropylidene group(s) gave monosaccharide esters with overall yields of 59–88%, where the monoester content was at least 80% (galactose oleate) and typically 90% for the other preparations. In contrast to sugar fatty acid esters prepared by conventional, high-temperature (trans)esterification, the enzymatically obtained monosaccharide esters contained no appreciable quantities of undersirable side products, and the only contaminants were monosaccharides and fatty acids.     

Behavioral and sociometric methods of identifying cooperators, competitors, and individualists: Support for the validity of the social orientation construct.

Cooperative, competitive, and individualistic social orientation of 132 4th–6th graders was assessed using a behavioral choice point and a sociometric measure. The classifications based on responses to the 2 measures are consistently related, and results are interpreted in terms of the convergent validity of the social orientation construct. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A picture integration task for measuring iconic memory in schizophrenics.

Two previous studies by the 1st author et al (1977) and G. Sperling (1960) using different techniques (partial report and backward masking) have found at least some subgroups of schizophrenics deficient in iconic memory. Both hypothesized that the icon in some schizophrenics might be either weakly formed, limited in capacity, or abnormal in duration, but neither study was able to test the qualities of the icon independent of possible transfer difficulties. The present study with 50 male 18–55 yr old psychiatric patients (35 schizophrenics and 15 nonpsychotics) developed a picture integration task that was analogous to C. W. Eriksen and J. F. Collins's (1973) random dot integration. With this task, the capacity and decay of the icon independent of transfer to short-term store was assessed. The icon itself was found intact in all schizophrenics. Other explanations are suggested for schizophrenics' inadequate partial report and backward masking performance. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Measurement of the absorption spectrum of polytetrafluoroethylene in the near millimetre region by an untuned cavity

The absorption spectrum of polytetrafluoroethylene has been measured between 3 and 15 cm^?1, a region which until now has been virtually unexplored. Absorption was found to arise almost entirely from amorphous regions of the sample and absorption in crystalline regions is small. A novel feature of the investigation is that measurements are made in an untuned cavity which has the advantage for low loss materials, that losses from reflection, scatter, and diffraction become unimportant. Loss measurements can be made on samples even when they are in the form of fine powder.     

MEMS interdigitated electrode pattern optimization for a unimorph piezoelectric beam

This paper presents optimization of interdigitated (d ₃₃ ) piezoelectric MEMS unimorph cantilever beams for harvesting vibration energy or for tuning resonators. The analysis of the poling behavior of the piezoelectric material is the key feature. While it is common that simplified models of interdigitated piezoelectric devices assume some uniform and well-defined poling pattern, the finite element modeling used in this work shows that not to be the case. A percent poling factor is developed to investigate the real losses associated with non-uniform poling. A parametric study in terms of electrode patterns, piezoelectric layer dimensions, and electrode dimensions is carried out to examine their effect on the percent poling factor. Design guidelines are provided to help ensure that such piezoelectric MEMS devices are developed to obtain optimum energy harvesting or tuning performance.     

Ferroelectric electrode interactions in BaTiO3 and PZT thin films

Abstract

We have studied ferroelectric thin films deposited by sol-gel processing onto non-noble metal substrates. The results obtained indicate that by careful control of processing conditions, ferroelectric materials can be deposited onto these substrates, although interdiffusion between the metal and the ferroelectric can significantly degrade the ferroelectric properties of the materials. The effects of this interdiffusion are demonstrated and possible implications of ferroelectric-electrode interactions for fatigue in ferroelectric materials are discussed.     

Mobile Agent-Based Management in the INSERT Project

This paper describes work carried out atUniversity College London to evaluate the use of MobileAgents (MA), written in Java, in network and systemmanagement. The work draws on experience fromconventional management systems based on ISO CommonManagement Information Protocol (CMIP) andInternet Simple Network ManagementProtocol (SNMP). These systems make use of theconcept of a Managed Object (MO). The paper describes the way in which the MOconcept has been translated into a form suitable forMA-based management and how the features of the Javalanguage may be used to express management information and to implement MOs. A platform has beenimplemented which allows MOs to be instantiated,controlled and stored. The platform also allows the easyproduction of MAs, their launching into the system and their subsequent management. Details of theplatform implementation are given and an initialassessment of performance is presented.     

Boundary Shear in Circular Pipes Running Partially Full

The distribution of boundary shear stress in circular conduits flowing partially full, with and without a smooth flat bed simulating deposited sediments, has been examined experimentally ranging from 0.375 < F < 1.96 and 6.5 × 104 < R < 3.42 × 105, using the Preston tube technique The invert level of the flat bed and the water depth have been varied to simulate a wide range of possible flow conditions that may occur in culverts, sewers, and hydropower tunnels. The distribution of boundary shear stress around the wetted perimeter is shown to be highly sensitive to changes in cross-sectional shape. The results have been analyzed in terms of the variation of local∕global shear stress versus perimetric distance, and the percentage of the total shear force acting on the wall or bed of the conduit. The %SFw results have been shown to agree well with Knight's empirical formula for prismatic channels. The influence of secondary flows on the distribution of boundary shear stress and the implications of this for sediment transport have also been examined.