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31.
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. 相似文献
32.
R. M. Butler 《加拿大化工杂志》1991,69(4):819-824
Petroleum can be produced more efficiently using horizontal wells instead of conventional wells. For a typical 16 hectare well spacing, the pressure drawdown is as small as one-fiftieth of that for conventional wells. In some cases, where coning is a problem in conventional production, horizontal wells allow operation with much less coproduction of the displacing fluid. In the thermal recovery of bitumen and heavy oils, the Steam-Assisted Gravity Drainage process with horizontal production wells allows the systematic sweeping of the reservoir with economic production rates and without steam bypass. This paper described and reviews the application of horizontal wells to the production of heavy crude oils and bitumen by both non-thermal and thermal methods. 相似文献
33.
K.M. McNamara K.K. Gleason D.J. Vestyck J.E. Butler 《Diamond and Related Materials》1992,1(12):1145-1155
The quality of chemically vapor deposited diamond films was assessed in terms of sp2/sp3 content as determined by solid-state nuclear magnetic resonance (NMR) and Raman spectroscopy. While the results of the two techniques are in qualitative agreement, only the NMR spectra yield quantitative values for the sp2/sp3 ratio. Only sp3 carbon was observed in the NMR spectra of very high quality hot-filament, microwave plasma, and d.c. arc-jet chemically vapor deposited films. As expected, Raman spectroscopy is extremely sensitive to sp2 bonded carbon, identifying small amounts below the detection limit of the NMR spectrometer. Comparison of the two techniques, however, indicates that Raman spectroscopy may be so sensitive to sp2 bonded carbon that sp3 bonded carbon in films containing as much as 90% sp3 bonded material may remain undetected. NMR linewidths indicate that the sp3 carbon in such material shows more disorder than that found in high-quality polycrystalline films. 相似文献
34.
The effect of adding an oxygenated poison (O2, CO or H2O) to a hydrogen/nitrogen stream producing ammonia over a triply promoted (K2O, CaO, Al2O3) commercial catalyst is not unsurprisingly rapidly to poison the catalyst. However, immediately the oxygenated poison reacts with the catalyst and before total poisoning has occurred, which in these experiments took 10 min, there was an explosive release of ammonia producing concentrations in the gas phase in excess of the equilibrium value. This is thought to be due to a convulsive reorganisation of the surface of the catalyst in forming regions of an oxide overlayer, resulting in the expulsion of the standing surface nitrogen atom coverage as ammonia. However, in contradistinction to the observation of complete poisoning of the triply promoted catalyst shortly after switching the water (2.9%) into the hydrogen/nitrogen stream, when polycrystalline iron was used as the catalyst, after the initial pulse of ammonia was observed, the small quantity of water (2.9%) in the hydrogen/nitrogen stream resulted in an increased rate ( ×3) of ammonia synthesis which declined only slightly over the twenty minute duration of the experiment. The difference in behaviour between the triply promoted catalyst and the polycrystalline iron is thought to be due to the relative ease of reduction of the latter, so that submonolayer quantities of oxide can be stabilised on the surface of the polycrystalline iron. The promoting effect of this oxide overlayer is either structural or electronic; no distinction can be made from these experiments. The technique of injecting either O2 or CO into a hydrogen/nitrogen stream which is producing ammonia over promoted catalysts in quantities insufficient to cause complete poisoning and measuring the oxygen coverage of the catalyst to a measured decrease in the ammonia synthesis rate, appears to be a ready, in situ method for the determination of the active catalyst area. 相似文献
35.
Adam Bates Benjamin Mood Joe Pletcher Hannah Pruse Masoud Valafar Kevin Butler 《International Journal of Information Security》2014,13(2):171-189
Virtualization is the cornerstone of the developing third-party compute industry, allowing cloud providers to instantiate multiple virtual machines (VMs) on a single set of physical resources. Customers utilize cloud resources alongside unknown and untrusted parties, creating the co-resident threat—unless perfect isolation is provided by the virtual hypervisor, there exists the possibility for unauthorized access to sensitive customer information through the exploitation of covert side channels. This paper presents co-resident watermarking, a traffic analysis attack that allows a malicious co-resident VM to inject a watermark signature into the network flow of a target instance. This watermark can be used to exfiltrate and broadcast co-residency data from the physical machine, compromising isolation without reliance on internal side channels. As a result, our approach is difficult to defend against without costly underutilization of the physical machine. We evaluate co-resident watermarkingunder a large variety of conditions, system loads and hardware configurations, from a local laboratory environment to production cloud environments (Futuregrid and the University of Oregon’s ACISS). We demonstrate the ability to initiate a covert channel of 4 bits per second, and we can confirm co-residency with a target VM instance in $<$ 10 s. We also show that passive load measurement of the target and subsequent behavior profiling is possible with this attack. We go on to consider the detectability of co-resident watermarking, extending our scheme to create a subtler watermarking attack by imitating legitimate cloud customer behavior. Our investigation demonstrates the need for the careful design of hardware to be used in the cloud. 相似文献
36.
Larry G. Butler David J. Riedl D. G. Lebryk H. J. Blytt 《Journal of the American Oil Chemists' Society》1984,61(5):916-920
The grain of some varieties of sorghum contains 2% or more condensed tannin; many other varieties contain no tannin at all.
Agronomic advantages, e.g., resistance to bird depredation, are associated with high-tannin sorghums, which have relatively
low nutritional value for nonruminants. The biological effects of tannin are a result of its propensity for binding proteins;
both hydrogen bonding and hydrophobic interactions are involved. Sorghum tannins can bind dietary proteins and reduce their
digestibility. Purified digestive enzymes are inhibited by tannin, but significant inhibition in vivo is unlikely. Proteins
differ greatly in their affinity for tannin. Those with highest affinity are large, have an open structure, contain no bound
carbohydrate and are rich in proline. Sorghum proteins of the alcohol-soluble prolamine fraction associate strongly with tannin,
are difficult to remove during tannin purification and are found combined with tannin in the indigestible residue after in
vitro digestion with pepsin. On germination, the seed may sacrifice a portion of these proteins to bind the tannin that might
otherwise interfere with metabolism by inhibiting seed enzymes. During seed development, tannin molecules are relatively short
and do not effectively precipitate proteins; as the seed dries, tannins undergo polymerization to an average of ca. 6 flavan-3-ol
units/molecule. The antinutritional effects of sorghum tannins can be eliminated by soaking the grain in dilute aqueous alkali,
but not by cooking. When rats are put on high-tannin sorghum diets, their parotid glands undergo hypertrophy and produce a
group of unique salivary proteins with extremely high affinity for tannin. These proteins contain over 40% proline and are
devoid of sulfur-containing and aromatic amino acids. This metabolic adaption may protect rats against tannin by binding and
inactivating it immediately when it enters the digestive tract.
Presented at the AOCS Meeting, May 11, 1983. 相似文献
37.
Cancer treatment is a fragmented and varied process, as “cancer” is really hundreds of different diseases. The “hallmarks of cancer” proposed by Hanahan and Weinberg (Cell 100(1):57–70, 2000) are a framework for viewing cancer within a common set of underlying principles—ten properties that are common to almost all cancers, allowing them to grow uncontrollably and ravage the body. We used a cellular automaton model of tumour growth paired with lattice Boltzmann methods modelling oxygen flow to simulate combination drugs targeted at knocking out pairs of hallmarks. We found that knocking out some pairs of cancer-enabling hallmarks did not prevent tumour formation, while other pairs significantly prevent tumour growth (\(p=0.0004\) using Wilcoxon signed-rank adjusted with the Bonferroni correction for multiple comparisons). This is not what would be expected from models of knocking out the hallmarks individually, as many pairs did not have an additive effect but had either no statistically significant effect or a multiplicative one. We propose that targeting certain pairs of cancer hallmarks, specifically cancers ability to induce blood vessel development paired with another cancer hallmark, could prove an effective cancer treatment option. 相似文献
38.
Joan Cahill Peter Redmond Sofiane Yous Gerard Lacey William Butler 《Cognition, Technology & Work》2013,15(2):219-238
Ground collisions have serious implications from both a safety and a commercial perspective. This paper reports on human computer interaction (HCI) research related to the advancement of a collision avoidance system, for use by Pilots operating on the airport ramp and in taxiway areas. Primarily, this paper focuses on the key findings of this research and the emerging HCI design solution. 相似文献
39.
The purpose of this study was to measure the team skills of operational crime scene examiners (CSEs). The techniques used were based on established methods and helped to gain a greater understanding of the domain of forensic investigation. The research begins with a hierarchical task analysis and then adapts pre-established methods for measuring the performance of CSEs in four UK Police Forces. The process supports comparison between prescribed methods of 'good practice' and real world practice. This has allowed the identification of the distributed skills and tasks of the CSE. Using Annett et al.'s HTA(T), crime scene examination can be categorised and the communications and coordination structures occurring between teams investigating a burglary considered. This makes it possible to generalise the method to situations involving ad hoc teams. 相似文献
40.