Bureau of Commercial Fisheries Oil Research program

Summary The Bureau of Commercial Fisheries has had under way since 1955 an extensive research program to develop wider uses for fish oils. The program is carried out in the Bureau’s own laboratories, in university laboratories, and in other qualified laboratories. The initial effort has been concentrated largely on basic research in an effort to learn more about the chemistry of fish oils, a field heretofore incompletely explored. Some applied research projects also were begun concurrently. Basic studies are being carried out on the chemistry of the components of fish oils (for example, polyene fatty acids), on the extracted fish oils themselves, and onin situ fish oils of the fish tissue. Investigations of fish-oil fatty acids are being made on chemical structure, methods of separation, chemical reactions, oxidative deterioration, and nutritive value, with especial emphasis on possible therapeutic aspects for human beings. The applied research projects include investigation of fish oils and the chemically modified compounds thereof as fungicides, as leather lubricants, and as ore-flotation agents. The applied and basic programs are coordinated so that findings of the basic work can be put to use in the applied work as soon as available.     

An Optimization Approach for Assessing the Reliability of Rainwater Harvesting

This study was aimed at developing an optimization approach to rainwater harvesting (RWH) considering three (3) water consumption scenarios (WCS). These scenarios which include basic water need (BWN), pour flush (PF) and full plumbing connection (FPC) corresponding to 50 litres per capita per day (lpcd), 75(lpcd) and 150(lpcd) respectively were simulated for different categories of buildings. Reliability of supply was determined by first obtaining composite surplus/deficit of rainwater followed by optimizing the redistribution of surplus rainwater harvested to deficient buildings. Results showed that when total annual rainfall intercepted by roof exceeded total demand, 100% reliability of water supply was guaranteed. Reliability was found to be a linear function of storage. When reliability of supply is possible, the optimized storage bears an inverse exponential relationship to the roof plan area per capita. The relationship between surplus/deficit and roof plan area per capita follows a one-phase decay pattern. An optimal redistribution of surplus water from self-sufficient buildings to deficient ones gave an improvement in supply reliability from 64 to 87% for basic water need, 47 to 58% for pour flush and 28 to 29% for full plumbing connection.     

Homogeneous Catalysis for the Production of Fine Chemicals. Palladium- and Nickel-Catalysed Aromatic Carbon–Carbon Bond Formation

In this article we describe our recent efforts in the area of palladium- and nickel-catalysed aromatic substitution reactions. Main focus is on low cost and low waste production methods. The use of aromatic carboxylic anhydrides in the Heck reaction leads to a waste-free protocol. In addition these reactions are easy to work up as no ligands or bases are used. For Heck reactions where substrates or products do not tolerate high temperatures we found that use of a bulky phosphoramidite (13b) as ligand for palladium leads to a very fast reaction at low temperatures. Recycle of palladium in ligand-free Heck and Suzuki reactions is easily accomplished by treating the palladium black that precipitates at the end of the reaction on a carrier material with a small excess of I₂ prior to its re-use in the next run. Use of aryl chlorides in the palladium- and nickel-catalysed formation of biaryls can be accomplished by using the nickel-catalysed coupling with arylzinc chlorides. Better still, it was possible to make use of the arylgrignard and use a catalytic amount of ZnCl₂. Whereas the strength of these aromatic substitution reactions lies in their broad tolerance of functional groups, one exception was the Sonogashira reaction on 3-bromoaniline. The problem was solved by making use of in situ catalytic protection of the NH₂ group with benzaldehyde.     

Volatile compounds produced by irradiation of butterfat

Anhydrous butterfat was irradiated at 6 megarads in a special glass reaction flask, and the headspace and total condensate samples were examined by wide-range (−180C to 125C) gas chromatography combined with mass spectrometry. The nature and amounts of volatile compounds were not greatly influenced by whether the butterfat was irradiated under oxygen or under vacuum, nor (apart fromn-alkanoic acids) by storage for 1 and 9 weeks. Carbon dioxide was produced in greatest amount. Of the remaining compounds, aliphatic hydrocarbons predominated both in number and amount. Aliphatic oxygenated compounds including carbonyl compounds were isolated in relatively small amounts. The following compounds were identified positively: C_1–13 n-alkanes; C_4–9 2-methylalkanes; C_2–14 alk-l-enes; C_2–9 alk-l-ynes; C_2–5 n-alkanoic acids; C_1–5 n-alkan-l-ols and propan-2-ol; C_2–8 n-alkanals and 2-methylbut-2-enal; C_3–5,7 alkan-2-ones; C_1–4 n-alkyl formates, vinyl and isoamyl formate, methyl acetate and methyln-hexanoate; and carbon dioxide. Visiting Scientist from Division of Dairy Research, C.S.I.R.O., Highett, Victoria, Australia.     

Automatic and Efficient Human Pose Estimation for Sign Language Videos

We present a fully automatic arm and hand tracker that detects joint positions over continuous sign language video sequences of more than an hour in length. To achieve this, we make contributions in four areas: (i) we show that the overlaid signer can be separated from the background TV broadcast using co-segmentation over all frames with a layered model; (ii) we show that joint positions (shoulders, elbows, wrists) can be predicted per-frame using a random forest regressor given only this segmentation and a colour model; (iii) we show that the random forest can be trained from an existing semi-automatic, but computationally expensive, tracker; and, (iv) introduce an evaluator to assess whether the predicted joint positions are correct for each frame. The method is applied to 20 signing footage videos with changing background, challenging imaging conditions, and for different signers. Our framework outperforms the state-of-the-art long term tracker by Buehler et al. (International Journal of Computer Vision 95:180–197, 2011), does not require the manual annotation of that work, and, after automatic initialisation, performs tracking in real-time. We also achieve superior joint localisation results to those obtained using the pose estimation method of Yang and Ramanan  (Proceedings of the IEEE conference on computer vision and pattern recognition, 2011).     

Spectral and complexity analysis of scalp EEG characteristics for mild cognitive impairment and early Alzheimer's disease

Amnestic mild cognitive impairment (aMCI) often is an early stage of Alzheimer's disease (AD). MCI is characterized by cognitive decline departing from normal cognitive aging but that does not significantly interfere with daily activities. This study explores the potential of scalp EEG for early detection of alterations from cognitively normal status of older adults signifying MCI and AD. Resting 32-channel EEG records from 48 age-matched participants (mean age 75.7 years)—15 normal controls (NC), 16 early MCI, and 17 early stage AD—are examined. Regional spectral and complexity features are computed and used in a support vector machine model to discriminate between groups. Analyses based on three-way classifications demonstrate overall discrimination accuracies of 83.3%, 85.4%, and 79.2% for resting eyes open, counting eyes closed, and resting eyes closed protocols, respectively. These results demonstrate the great promise for scalp EEG spectral and complexity features as noninvasive biomarkers for detection of MCI and early AD.     

Advances and future prospects in copper electrowinning

In recent years research on the electrowinning of copper has led to a number of significant advances. These developments include improved mass transfer and higher current density operation through air sparging, reduced anode overvoltage in the conventional cell as a result of cobalt(II) addition to the electrolyte or the use of alternative types of anodes, and the production of high quality cathodes in the electrowinning of copper from solvent extraction strip liquor. The fluidized-bed cathode offers the possibility of continuous electrowinning as well as the direct electrowinning of copper from dilute solutions. The problem of high power consumption may find its solution in the adoption of an alternate anode reaction or in the electrowinning of copper (I) electrolytes. Noteworthy is the development of unique electrowinning cells in conjunction with the hydrometallurgical treatment of copper concentrates. These cells utilize cuprous or ferrous anodic oxidation with the resulting cupric or ferric ions being active lixiviants of sulphide copper minerals. The numerous advances combined with the increasing tonnage of copper being produced by the electrowinning route ensure an interesting and promising future for this process.     

CLATHRATE HYDRATE FORMATION ENHANCES NEAR-CRITICAL AND SUPERCRITICAL SOLVENT EXTRACTION EQUILIBRIA

Pre-concentration of dilute aqueous solutions by hydrate formation can improve the effective distribution coefficient and selectivity of solvent extraction. Many solvents can serve simultaneously to promote solution concentration by hydrate formation and also to extract non-polar solutes from the resulting concentrated solution. This concept is illustrated for systems with supercritical ethylene and with near-critical liquid carbon dioxide, and its application to conventional solvents is discussed.     

Mechanism of paper wet strength development by polycarboxylic acids with different molecular weight and glutaraldehyde/poly(vinyl alcohol)

In our previous research, we found that crosslinking paper using poly(carboxylic acid)s with different molecular weight or using the combination of glutaraldehyde and poly(vinyl alcohol) (PVA) significantly improved the wet strength of the paper. In this research, we studied the mechanism of paper wet strength development using crosslinking systems with different molecular weight by measuring scanning electron microscopic (SEM) images, wet strength, folding endurance, wet thickness, water retention, and Z‐direction tensile strength of the treated paper. The paper crosslinked by a high‐molecular weight (MW) poly(carboxylic acid) shows more swelling by water than that crosslinked by a low‐MW polycarboxylic acid in the SEM micrographs even though both treated paper samples have similar wet strength. Thus, the data suggest that high‐MW poly(carboxylic acid)s promote the formation of interfiber crosslinking. Crosslinking paper by glutaraldehyde, a crosslinking agent of small molecular size, improves wet strength and reduces flexibility and swellability of paper because of the formation of intrafiber crosslinking. Combining glutaraldehyde with PVA as a coreactant increases wet strength and also retains flexibility and swellability of the treated paper because of the formation of interfiber crosslinking. The hypothesis that PVA reacts with glutaraldehyde to form a polymeric pentanedialated‐PVA crosslinking system and promotes the formation of interfiber crosslinking on the paper is supported by the data of wet strength, folding endurance, wet thickness, water retention, and Z‐direction tensile strength of the treated paper. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 277–284, 2006