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941.
D. A. Morgan D. B. Shaw M. J. Sidebottom T. C. Soon R. S. Taylor 《Journal of the American Oil Chemists' Society》1985,62(2):292-299
The results presented in the literature, which attempt to elucidate the mechanisms by which triglyceride oils are bleached
by earths, are reviewed. The impact of this work and how the mechanistic proposals affect changes in oil properties are considered,
with particular emphasis on the needs of the palm oil processor. Important properties include color, metals and phosphorus
content and oxidative stability of the oil.
Investigations made in our own laboratories have been aimed at elucidating the effect of varying physical and chemical properties
of the bleaching earth on the quality of bleached and deodorized oils. Techniques used in this work are pore-size distribution,
surface area, scanning and transmission electron microscopy and a variety of chemical and X-ray analysis methods.
The ability to vary such parameters in montmorillonite clays by alteration of process conditions to give materials with specific
performance characteristics is demonstrated.
Comparisons are made between acid-activated montmorillonites and other clay types. 相似文献
942.
This study deals with some of the judgmental factors involved in selecting effect sizes from within the studies that enter a meta-analysis. Particular attention is paid to the conceptual redundancy rule that Smith, Glass, and Miller (1980) used in their study of the effectiveness of psychotherapy for deciding which effect sizes should and should not be counted in determining an overall effect size. Data from a random sample of 25 studies from Smith et al.'s (1980) population of psychotherapy outcome studies were first recoded and then reanalyzed meta-analytically. Using the conceptual redundancy rule, three coders independently coded effect sizes and identified more than twice as many of them per study as did Smith et al. Moreover, the treatment effect estimates associated with this larger sample of effects ranged between .30 and .50, about half the size claimed by Smith et al. Analyses of other rules for selecting effect sizes showed that average effect estimates also varied with these rules. Such results indicate that the average effect estimates derived from meta-analyses may depend heavily on judgmental factors that enter into how effect sizes are selected within each of the individual studies considered relevant to a meta-analysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
943.
944.
945.
Howard George S.; Maxwell Scott E.; Berra Susan M.; Sternitzke Mary E. 《Canadian Metallurgical Quarterly》1985,70(1):233
Updated the report of W. M. Cox and V. Catt (see record 1978-21651-001) by determining the 40 top contributing institutions to the Journal of Applied Psychology, 1976–1982, and assessed the generalizability of productivity rankings based solely on contributions to this journal. A number of industrial and organizational psychologists were asked to indicate all the journals in which psychologists in the field were likely to publish. Five journals suggested by these nominators were used for comparison in the review. A list of the 40 most productive graduate programs based on these 5 journals is included. Results show the inadequacy of Cox and Catt's decision to base productivity ratings solely on contributions to 1 journal. Using 5 journals, 4 programs were catapulted into the top 10 rankings, while 7 programs dropped from top rankings in the Cox study (1970–1975) to below the 65th rank in the present study. Using only the Journal of Applied Psychology contributions, 2 of these programs ranked in the top 10, 1976–1982. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
946.
A multi-channel continuous toxicity monitoring system developed in our laboratory, based on two-stage mini-bioreactors, was successfully implemented in the form of computer-based data acquisition. The multi-channel system consists of a series of a two-stage minibioreactor systems connected by a fiber optic probe to a luminometer, and uses genetically engineered bioluminescent bacteria for the detection of the potential toxicity from the soluble chemicals. This system can be stably and continuously operated due to the separation of the culture reactor from the test reactor and accomplish easy and long-term monitoring without system shut down by abrupt inflows of severe polluting chemicals. Four different recombinant bioluminescent bacteria were used in different channels so that the modes of the samples toxicities can be reasonably identified and evaluated based upon the response signature of each channel. The bioluminescent signatures were delivered from four channels by switching one at once, while the data is automatically logged to an IBM compatible computer. We also achieved the enhancement of the system through the manipulation of the dilution rate and the use of thermo-lux fusion strains. Finally, this system is now being implemented to a drinking water reservoir and river for remote sensing as an early warning system. 相似文献
947.
C Phanuwan S Takizawa K Oguma H Katayama A Yunika S Ohgaki 《Water science and technology》2006,54(3):203-210
Floodwaters in Kampung Melayu village, Jakarta, Indonesia, as well as river water and consumable water (including groundwater and tap water) samples in flooded and non-flooded areas, were quantitatively analysed to assess occurrence of viruses and total coliforms and E. coli as bacterial indicators after flooding event. High numbers of enterovirus, hepatitis A virus, norovirus (G1, G2) and adenovirus were detected at high concentration in floodwaters and waters sampled from Ciliwung River which runs across metropolitan Jakarta and is used widely for agriculture and domestic purposes by poor residents. One out of three groundwater wells in the flooded area was contaminated with all viruses tested while no viruses were found in groundwater samples in non-flooded areas and tap water samples. The results revealed that human enteric viruses, especially hepatitis A virus and adenovirus, were prevalent in Jakarta, Indonesia. This study suggested that flooding posed a higher risk of viral infection to the people through contamination of drinking water sources or direct contact with floodwaters. 相似文献
948.
Nitrification is a key step for reliable biological nitrogen removal. In order to enhance nitrification in the activated sludge (AS) process, membrane-attached biofilm (MAB) was incorporated in a conventional activated sludge tank. Simultaneous organic carbon removal and nitrification of the MAB incorporated activated sludge (AS + MAB) process was investigated with continuous wastewater treatment. The effluent TOC concentration of AS and the AS + MAB processes were about 6.3 mg/L and 7.9 mg/L, respectively. The TOC removal efficiency of both AS and AS + MAB were above 95% during the wastewater treatment, indicating excellent organic carbon removal performance in both processes. Little nitrification occurred in the AS process. On the contrary, successful nitrification was obtained with the AS + MAB process with nitrification efficiency of about 90%. The volumetric and surface nitrification rates were about 0.14 g/Ld and 6.5 g/m2d, respectively. The results clearly demonstrated that nitrification in the conventional AS process was boosted by MAB. Furthermore, the microfaunal population in the AS + MAB process was different from that in the AS process. The high concentration of rotifers in the AS + MAB process was expected to decrease the generation of excess sludge in the process. 相似文献
949.
The influence of liquid penetration at grain boundary regions on the rate of advance of the solid-liquid interface during
isothermal solidification of transient liquid phase (TLP) brazed nickel joints has been examined. The test samples used in
this study were Ohno-cast nickel with a grain size of >4 mm and a fine-grained nickel with a grain size of around 40 μm. Both
Ni-base materials had the same chemical composition. The rate of isothermal solidification was greater when fine-grained nickel
was employed during TLP brazing using Ni-11 wt pct P filler metal at 1200 °C. Liquid penetration at grain boundaries accelerates
the isothermal solidification process by increasing the effective solid-liquid interfacial area and increasing the rate of
solute diffusion into the base material. An analysis of electron channeling patterns has confirmed that random high-angle
boundaries have a greater influence on the rate of isothermal solidification than ordered boundaries including small-angle
or twin boundaries.
Formerly Visiting Scientist, Department of Metallurgy and Materials Science, University of Toronto.
Formerly Postdoctoral Fellow, Department of Metallurgy and Materials Science, University of Toronto 相似文献
950.