Vapour phase deposition and thermal decarbonylation of Re2(CO)10 on gamma-alumina: infrared studies

Dirheniumdecacarbonyl vacuum sublimed onto mesoporous -alumina forms Lewis type adducts where an axial CO group is coordinated to an A1³⁺ ion at the metal oxide surface, as revealed by IR spectroscopy. Vacuum heating of the surface adduct at 773 K brings about decarbonylation, with intermediate formation of a surface-bound mononuclear tricarbonyl which was completely decarbonylated on prolonged heating at the same temperature. The resulting material strongly chemisorbs CO to yield mainly a surface-bound pentacarbonyl species. This suggests that the supported metal remains primarily in a zero-valent and well dispersed state.     

Psychometric evaluation of the Beck Anxiety Inventory with older medical patients.

Disadvantaged older medical outpatients (N?=? 197; ages 55–92) completed the Beck Anxiety Inventory (BAI). The instrument demonstrated high internal consistency and no significant differences by sex or race, suggesting that it is appropriate to use with diverse populations. Total BAI score correlated negatively with age. Confirmatory factor analysis revealed a good fit to a 4-factor model consisting of cognitive, autonomic, neuromotor, and panic symptoms. Although scores on the BAI and 2 widely used depression scales were significantly correlated, factor analysis distinguished BAI and depression scale items, suggesting that the instruments measure distinct constructs. These findings suggest that the BAI could serve as a valuable screening test for anxiety symptoms among primary care patients who are older and have low income. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Design considerations with ventilation-radiators: Comparisons to traditional two-panel radiators

Performance of heat emitters in a room is affected by their interaction with the ventilation system. A radiator gives more heat output with increased air flow along its heat transferring surface, and with increased thermal difference to surrounding air. Radiator heat output and comfort temperatures in a small one-person office were studied using different positions for the ventilation air inlet. In two of the four test cases the air inlet was placed between radiator panels to form ventilation-radiator systems. Investigations were made by CFD (Computational Fluid Dynamics) simulations, and included visualisation of thermal comfort conditions, as well as radiator heat output comparisons. The room model was exhaust-ventilated, with an air exchange rate equal to what is recommended for Swedish offices (7 l s⁻¹ per person) and cold infiltration air (−5 °C) typical of a winter day in Stockholm.Results showed that under these conditions ventilation-radiators were able to create a more stable thermal climate than the traditional radiator ventilation arrangements. In addition, when using ventilation-radiators the desired thermal climate could be achieved with a radiator surface temperature as much as 7.8 °C lower. It was concluded that in exhaust-ventilated office rooms, ventilation-radiators can provide energy and environmental savings.     

An approach to multibeam covariance matrices for adaptive beamforming in ultrasonography

Medical ultrasound imaging systems are often based on transmitting, and recording the backscatter from, a series of focused broadband beams with overlapping coverage areas. When applying adaptive beamforming, a separate array covariance matrix for each image sample is usually formed. The data used to estimate any one of these covariance matrices is often limited to the recorded backscatter from a single transmitted beam, or that of some adjacent beams through additional focusing at reception. We propose to form, for each radial distance, a single covariance matrix covering all of the beams. The covariance matrix is estimated by combining the array samples after a sequenced time delay and phase shift. The time delay is identical to that performed in conventional delay-and-sum beamforming. The performance of the proposed approach in conjunction with the Capon beamformer is studied on both simulated data of scenes consisting of point targets and recorded ultrasound phantom data from a specially adapted commercial scanner. The results show that the proposed approach is more capable of resolving point targets and gives better defined cyst-like structures in speckle images compared with the conventional delay-and-sum approach. Furthermore, it shows both an increased robustness to noise and an increased ability to resolve point-like targets compared with the more traditional per-beam Capon beamformer.     

A rapid method for the analysis of hydrogenated fats by GC with IR detection

A rapid method for analysis of trans and cis FA in hydrogenated fats has been developed. The method is based on a single anlaysis by CG with IR detection. Multivariate partial least squares regression is applied on the IR spectra to predict the number of cis and trans double bonds. For each chain length the method provides information about the amount of the saturated FA, the amount of trans monoenes, the amount of cis monoenes, the amount of PUFA, and the average number of cis and trans double bonds in PUFA. The method has been validated by summing the values to a total trans value and total unsaturation. These sum values were compared with total trans unsaturation, as determined by AOCS method Cd 14-95, and iodine value, as determined by AOCS Cd 1d-92.     

Validation of the EUROP system for lamb classification in Norway; repeatability and accuracy of visual assessment and prediction of lamb carcass composition

The EUROP classification system is based on visual assessment of carcass conformation and fatness. The first objective was to test the EUROP classification repeatability and accuracy of the national senior assessors of the system in Norway. The second objective was to test the accuracy of the trained and certified abattoir EUROP classifiers in Norway relative to EU Commission's supervising assessors. The third and final objective was to test the accuracy of the EUROP classification system, as assessed by the National senior assessors, for prediction of lean meat, fat and bone percentage and lean meat in relation to bone ratio. The results showed that the repeatability and accuracy of the national senior assessors was good, achieving high correlations both for conformation and fatness. For the abattoir assessors, there were some systematic differences compared to EU Commission's assessors, but these differences were within limits accepted by EU Commission. The relationship between abattoir and national senior assessors was good, with only small systematic differences. This may suggest that there also is a systematic difference between the national senior assessors of the system and EU Commission's assessors. The EUROP system predicted lean meat percentage poorly (R(2)=0.407), with a prediction error for 3.027% lean. For fat and bone percentage, the results showed a fairly good prediction of fat percentage, but poorer for bone percentage, R(2)=0.796 and R(2)=0.450, respectively. The prediction error for fat and bone percentage was 2.300% and 2.125%, respectively. Lean: bone ratio was predicted poorly (R(2)=0.212), with a prediction error of 0.363 lean: bone ratio.     

The effect of heat treatment on the gouging abrasion resistance of alloy white cast irons

A series of heat treatments was employed to vary the microstructure of four commercially important alloy white cast irons, the wear resistance of which was then assessed by the ASTM jaw-crusher gouging abrasion test. Compared with the as-cast condition, standard austenitizing treatments produced a substantial increase in hardness, a marked decrease in the retained aus-tenite content in the matrix, and, in general, a significant improvement in gouging abrasion resistance. The gouging abrasion resistance tended to decline with increasing austenitizing tem-perature, although the changes in hardness and retained austenite content varied, depending on alloy composition. Subcritical heat treatment at 500 ° following hardening reduced the retained austenite content to values less than 10 pct, and in three of the alloys it caused a significant fall in both hardness and gouging abrasion resistance. The net result of the heat treatments was the development of optimal gouging abrasion resistance at intermediate levels of retained aus-tenite. The differing responses of the alloys to both high-temperature austenitizing treatments and to subcritical heat treatments at 500 ° were related to the effects of the differing carbon and alloying-element concentrations on changes in theM _s temperature and secondary carbide precipitation.     

Initial proteolysis of milk proteins and its effect on formation of ACE-inhibitory peptides during gastrointestinal proteolysis: a bioinformatic, in silico, approach

Angiotensin-I-converting enzyme (ACE)-inhibitory peptides are encrypted in milk protein sequences. They may express an antihypertensive effect if they are released by proteolysis in foods and/or during gastrointestinal digestion. A bioinformatic, in silico, approach was developed to evaluate how systematic initial proteolysis, i.e. cleavage after one specific type of amino acid (C-end) at a time in milk proteins, influence the formation of ACE-inhibitory peptides by subsequent gastrointestinal proteolysis. Computer simulation was done and a peptide QSAR model was used to estimate the combined ACE inhibition by digested proteins. Initial proteolytic cleavage at the C-end of amino acids isoleucine and proline gave, based on calculations, increased effect of ACE-inhibitory peptides after gastrointestinal proteolysis of milk proteins. Cleavage after most other amino acid residues had little or no effect. Results indicate that initial proteolysis in foods have to be specific in order to increase formation of bioavailable ACE-inhibitory peptides during gastrointestinal digestion.