The centrifugal acetone foots test applied to crude soybean oil. II. Rapid method compared with other measures of phosphatides content and refining loss

Summary Comparisons are made between eight methods of grading crude soybean oil with respect to a laboratory refining loss determination which closely simulates commercial wash kettle practice. This list of methods includes the five analysis factors, acetoneinsoluble, HCl heat break, centrifugal foots, phosphorus and ash contents, each combined with percentage of ffa and moisture and volatile. It includes the official A.O.C.S. cup loss, the Wesson loss, and the chromatographic absorption loss determinations. On 12 crudes on which laboratory wash extraction loss and losses determined from centrifugal foots values, from acetone-insoluble contents, and from HCl break values were available, the centrifugal foots values best predicted the refining loss. The standard deviations of each method from the wash extraction loss were, respectively, 0.21%, 0.27%, and 0.29%. On seven of these crudes on which all nine determinations were available, acetone insoluble content showed the best correlation, followed by centrifugal foots and HCl heat break. The centrifugal foots test generally gives zero or trace results on degummed oil. By use of this method however the refining loss grade of crude soybean oils may be estimated in as little as one hour of elapsed time, and it requires only 5 to 10 minutes of the operator's time.     

Biogeochemistry of organic and inorganic arsenic species in a forested catchment in Germany

Little is known about the fate and behavior of diffuse inputs of arsenic (As) species in forested catchments which often are the sources of drinking water. The objective of this study was to investigate the mobility and transformation of different As species in forest ecosystems to assess the environmental risk related to the diffuse pollution of As. We determined concentrations and fluxes in precipitation, litterfall, soil solutions (Oa horizon and 20- and 90-cm depth), and runoff of organic and inorganic As species and Astotal in a forest ecosystem in NE-Bavaria, Germany. The concentrations of Astotal were mostly <1 microg As L(-1) in aqueous samples and were highest in forestfloor percolates (7.6 microg As L(-1)). In litterfall, the concentrations of As species never exceeded 0.1 microg As g(-1). Arsenate and arsenite were the prevalent As species in all samples. Organic As species, comprising monomethylarsonic acid, dimethylarsinic acid, trimethylarsine oxide, arsenobetaine, and three unidentified organic As species, were mostly found in throughfall reaching up to 45% of Astotal. The total deposition of Astotal (calculated as throughfall + litterfall) was 5.6 g As ha(-1) yr(-1) with 16% contribution of litterfall. The annual Astotal fluxes were 30 g As ha(-1) yr(-1) for forest floor percolates, 8.0 g As ha(-1) yr(-1) at 20-cm soil depth, and 1.4 g As ha(-1) yr(-1) at 90-cm soil depth. The annual runoff of Astotal from the catchment amounted to 3.8 g As ha(-1) yr(-1). The annual fluxes of total organic As species was highest in total deposition (1.1 g As ha(-1) yr(-1)) and decreased largely with depth in the soil profile. The annual runoff of total organic As species was only 0.08 g As ha(-1) yr(-1). Significant correlations in soil solutions and runoff were found between Astotal and dissolved organic C and Fe. Correlations between Astotal concentrations in runoff and water fluxes were seasonally dependent and with a steeper slope in the growing season than in the dormant season. The elevated concentrations of organic As species in throughfall indicate microbial methylation of As in the phyllosphere, but no evidence for methylation in the soil was found. The mass balance of the catchment points out the strong retention and probable degradation or oxidation of organic As species and arsenite but also to mobilizable pools of Astotal and arsenate. The forest floor is presently a source, whereas the mineral soil is a sink for Astotal and arsenate. The As concentrations in runoff seem to be controlled by As mobilization from forest floor and riparian wetland soils during heavy rain events and superficial flow. The risk for excessment of the drinking water threshold concentrations of As in runoff and soil solutions is considered low at our site.     

New Two-Frequency Method and Devices for Electromagnetic Levitation Drip- and Leakage-Free Melting of Metals

A new method and devices for the electromagnetic levitation melting of metallic samples with greater weights and axisymmetrically stabilized positions is presented in this paper.The new method is applying two homogeneous magnetic fields of different frequencies,whose field lines are in absence of a charge horizontally and reciprocally normal in order to exert electromagnetic lift forces also on the axis of the levitated sample.Therefore the weight of the charge can be increased and the charge can be drip-and leakage-free melted.The method can be used in a melting furnace with or without a cold protective wall,as well as for the coreless induction valves applied for flow rate control,e.g.in the continuous casting of molten metals.The applicability of the method was experimentally examined and proved by tests conducted with three types of laboratory setups.     

Cross-section analysis of organic light-emitting diodes

The 'lift-out' technique using a focused ion beam microscope was applied to prepare cross-sectional specimens of organic light-emitting diodes for use in transmission electron microscopy. The focused ion beam equally thins the organic/inorganic hybrid devices despite the difference in material hardness of the compounds. This allowed to overcome preparation difficulties of conventional techniques such as ion thinning or ultra-microtomy. Two different samples were prepared and studied by both conventional transmission electron microscopy and analytical electron microscopy to display some of the investigation possibilities which become available with this sample preparation method.     

The relationship between ethnicity and advance directives in a frail older population

OBJECTIVE: To assess the relationship between ethnicity and Health Care wishes, including Advance Directives, in a group of frail older persons in PACE (Program For All Inclusive Care Of The Elderly). DESIGN: Retrospective chart review of 1193 participants in the PACE program. SETTING: Program of All Inclusive Care Of The Elderly (PACE), a comprehensive managed care demonstration program serving frail older participants at 10 sites across the nation. PARTICIPANTS: A total of 1193 older adults, all of whom met state criteria for nursing home level of care. There were 385 non-Hispanic whites, 364 blacks, 156 Hispanics, and 288 Asians. MEASUREMENTS: Presence or absence of advance directives, type of health care wishes selected including living will, durable power of attorney, and health care proxy. RESULTS: Frail older white, black, Hispanic and Asian Americans differ significantly in their health care wishes and how they choose to express them. Blacks were significantly more likely to select aggressive interventions and less likely than non-Hispanic whites and Hispanics to utilize a written instrument for expressing health care wishes. Whites were significantly more likely to utilize written documents for advance directives, whereas Asians were more likely to select less aggressive interventions but were unlikely to use written advance directives. CONCLUSIONS: In this population, we found significant ethnic variations in choice of health care wishes. Although health care wishes are an individual decision, an awareness of cross cultural patterns can assist practitioners in addressing the concerns of their patients, as well as assisting Health Care Policy Development.