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81.
Jonathan A. Zerkowski Michael J. Haas 《Journal of the American Oil Chemists' Society》2011,88(8):1229-1237
This paper reports the synthesis of a series of novel compounds where carboxylic acids have been linked to a phenol through
amidomethyl units. For instance, one, two, or three fatty acids have been selectively appended to the phenol in yields above
75%. The fatty acid used was oleic acid, which was subsequently epoxidized. Other functional groups, such as amino acids,
can be incorporated in these compounds. Examples of monomers that are suitable for polymerization were also prepared: one
acrylamide, one styrene derivative, and two types of AB2 diamino acids, all of which contain oleic units that are sites for epoxidation and crosslinking. Fatty acid aryl ethers were
prepared using hydroxy fatty acids. These molecules are intended to serve as augmented analogues of epoxidized vegetable oil.
Their amide groups should lead to intermolecular aggregation through hydrogen bonding, and the option to covalently include
other functional groups may permit tuning of the macroscopic materials properties of films, coatings, or solids constructed
from them. 相似文献
82.
E Topinková J Neuwirth M Stanková A Mellanová T Haas 《Canadian Metallurgical Quarterly》1997,136(18):573-577
BACKGROUND: Incontinence represents one of the common problems in long-term care geriatric facilities and nursing homes. However, in the Czech Republic data on prevalence, severity and incontinence-associated factors for nursing home residents are not available. The aim of the study was to report the prevalence of urinary (UI) and bowel incontinence (BI) in different geriatric facilities and to identify factors positively associated with incontinence. METHODS AND RESULTS: In a sample of 1162 residents of 18 long-term care facilities UI has been found in 684 residents (63.3%). Health and social care facilities did not differ significantly (60.7 vs 65.6%). Of the incontinent 294 residents (27.2%) suffered from permanent/daily incontinence, 390 (36.1%) from occasional transitory UI. Prevalence of BI reached 54.4%, as well as double incontinence (45.9%). Cognitive impairment, self-care ADL and/or mobility dependency and bed rest are factors significantly associated with UI (for all P < 0.001). However, age, gender and urinary tract infection did not reach the statistical significance (P = 0.280-0.069). Risk adjustment/stratification for UI revealed the prevalence of 33.0% in the low risk group. In the high risk group (high ADL dependency and severe cognitive impairment) the prevalence came up to 96.0%. CONCLUSIONS: Our study presents the first results focused on incontinence problem in long-term care geriatric institutions in the Czech Republic. High prevalence of this condition makes incontinence an important medical, nursing and economical yet neglected problem. 相似文献
83.
This study investigated the enactment effect from the perspective of the item-order hypothesis (e.g., M. Serra & J. S. Naime, 1993). The authors assumed that in subject-performed tasks (SPTs), item encoding is improved but order encoding is disrupted compared with experimenter-performed tasks (EPTs), that order encoding of EPTs is only better in pure lists, and that the item-order hypothesis is confined to short lists. Item information was tested in recognition memory tests, order information in order reconstruction tasks, and both item and order information in free-recall tests. The results of 5 experiments using short (8 items) and long lists (24 items) in a design with list type (pure, mixed) and encoding condition (EPT, SPT) as factors supported the hypotheses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
The evolution of a temperature gradient at the free surface of a coating solution during the spin coating process is examined. Solvent evaporation causes localized cooling at the top that can result in thermocapillary instability within the coating solution, and thereby driving convective flows that may result in non-uniform coatings. We examine the evolution of these temperature gradients by using a one dimensional finite difference model that simultaneously describes the thinning behavior (both by flow and by evaporation) and the temperature evolution within the solution. The entire system is initially isothermal but is subject to evaporation-driven cooling at the free surface of the gradually thinning fluid. The model is then used to determine the magnitude of the thermocapillary effects during the spin coating process. As test systems we simulate the spin coating of several pure alcohol solutions having different volatilities and therefore different evaporative-cooling powers. As the fluid thins, we calculate the instantaneous Marangoni (Mn) number, which signifies the magnitude of thermocapillary-driven convection. We compare these Mn values against their relevant threshold values, determined from prior reports in the literature, in order to deduce the magnitude of the instabilities they represent. If the Mn value is super-critical, then the instability that it represents will be sufficient for the onset of convection cells within a stagnant fluid layer of corresponding thickness. Because the radial outflow is fully laminar under normal conditions, super-critical Mn values imply that similar instabilities would arise within a spinning solution. Super-critical Mn values were observed under numerous conditions suggesting that thermocapillary instability may be responsible for striation features that develop in coatings made by spin coating. Trends related to spin-speed, solvent volatility, and initial solution thickness are discussed with the goal of improving the flatness of coatings that are made by this process. 相似文献
85.
Multiskilling is a workforce strategy that has been shown to reduce indirect labor costs, improve productivity, and reduce turnover. A multiskilled workforce is one in which the workers possess a range of skills that allow them to participate in more than one work process. In practice, they may work across craft boundaries. The success of multiskilling greatly relies on the foreman’s ability to assign workers to appropriate tasks and to compose crews effectively. The foreman assigns tasks to workers according to their knowledge, capabilities, and experience on former projects. This research investigated the mechanics of allocating a multiskilled workforce and developed a linear programming model to help optimize the multiskilled workforce assignment and allocation process in a construction project, or between the projects of one company. It is concluded that the model will be most useful in conditions where full employment does not exist; however, it is also useful for short term allocation decisions. By running the model for various simulated scenarios, additional observations were made. For example, it is concluded that, for a capital project, the benefits of multiskilling are marginal beyond approximately a 20% concentration of multiskilled workers in a project workforce. Benefits to workers themselves become marginal after acquiring competency in two or three crafts. These observations have been confirmed by field experience. Extension of this model to allocation of multifunctional resources, such as construction equipment, should also be possible. 相似文献
86.
Hepatitis C (HCV) is a serious infection caused by a blood-borne virus. It is a contagious disease spreading via a variety
of transmission mechanisms including contaminated tattoo equipment. Effectively regulating commercial tattoo parlours can
greatly reduce this risk. This paper models the cost-effectiveness and optimal timing of such interventions, and parameterises
the model with data for Vienna, Austria. This dynamic model of the contagious spread of HCV via tattooing and other mechanisms
accounts for secondary infections and shows that regulating tattoo parlours as done in Vienna, Austria in 2003, is a cost-saving
intervention. 相似文献
87.
György Csaba Paolo Lugli Markus Becherer Doris Schmitt-Landsiedel Wolfgang Porod 《Journal of Computational Electronics》2008,7(3):454-457
This paper presents a computational study of ion-beam patterned cobalt-platinum multilayers, which could be used for field-coupled
computing. We use micromagnetic simulations to reproduce measured hysteresis curves. This parameterized micromagnetic simulator
then will be used for simulating interacting magnetic dots. We demonstrate how logic gates can be built from such coupled
dots. We also show how electrical wires—placed beneath or above the magnetic dots—can provide a magnetic field, which propagates
the magnetic signals. 相似文献
88.
A new version of the Al/Cl2 battery previously described was investigated. Instead of a graphite cylinder, a porous titanium plate was used as a chlorine electrode (cathode). The electrolyte used was a moderately acidic aqueous NaCl solution of pH 2 containing small amounts of In3+ and Hg2+ as additives. The cell had an open-circuit voltage of 2.6 V and delivered a maximum power of 19.8 W at 1.1 V with a Faradiac efficiency of 69%. The power density was 280 mW cm–2. A module consiting of 4 submodules connected in series, where each submodule contained 4 double-unit cells connected in parallel, had an open-circuit voltage of 10.6 V, a maximum power of 200 W and an energy density of 110 Whl–1. 相似文献
89.
Rudolf Scheidl Bernd Winkler Helmut Kogler Peter Ladner Rainer Haas Evgeny Lukachev 《BHM Berg- und Hüttenm?nnische Monatshefte》2016,161(11):504-509
Digital fluid systems are controlled solely by on-off valves, in contrast to analogue fluid systems which use continuously adjustable valves. Many digital fluid systems have been in practical use for some decades. The steel industry relies on several fluid technologies. Apart from the handling of the liquid steel, several other fluid processes exist to fulfill indispensable functions; examples include cooling, motion control, torch cutting, descaling, and lubricating. Many of these processes need better control concerning precision, dynamics, resource demand, reliability, and environmental impact or must offer additional functionalities for use in factories of the future. In several cases digital fluid systems are the better solutions. In this paper this is demonstrated by four examples, ranging from proven simple solutions and concepts going currently into industrial application to promising concepts for the future. 相似文献
90.
Franz Ferdinand Reinthaler Gebhard Feierl Herbert Galler Doris Haas Eva Leitner Franz Mascher Angelika Melkes Josefa Posch Ingrid Winter Gernot Zarfel Egon Marth 《Water research》2010,44(6):1981-1985
The aim of this study was to investigate the degree of contamination of sewage sludge with ESBL-producing Escherichia coli strains and the effectiveness of different sewage sludge treatment methods.Monthly sewage sludge samples were collected between January and September 2009 in 5 different sewage treatment plants and tested for the presence of ESBL E. coli. In addition, the number of colony forming units (CFU) of E. coli and coliform bacteria before and after the different sludge treatment methods (aerobic/anaerobic digestion, lime stabilization, and thermal treatment) was investigated.Of the 72 sewage sludge samples investigated, ESBL-positive E. coli were found in 44 (61.1%) sewage sludge samples. The classification of β-lactamase groups was carried out in 15 strains resulting in the detection of 2 different groups (CTX-M and TEM) of bla genes. All 15 of them had a CTX-M gene and 4 of these strains furthermore carried a TEM gene.With regard to the CFU of E. coli and coliform bacteria, thermal treatment and lime stabilization following dehydration sufficiently reduced pathogen concentrations. The plants using merely stabilization and dehydration showed an increase of E. coli and coliform bacteria and thus also an increase in ESBL-producing E. coli. 相似文献