Factors Affecting Color Formation During Storage of White Crystal Sugar

Abstract The rates of reaction at 27° 37°, 47°, and 57°, of 17-ketosteroids (17-KS), dehydroisoandrosterone (DHA), and 17-ketogenic steroids (17-KGS) were studied by a modified Zimmermann color reaction. Curves were constructed by plotting absorbance against time necessary for maximum color development at these temperatures. Pooled eluates of 17-KS and 17-KGS from normal urine samples were used in the determinations. Temperature was plotted against the time found necessary for maximum color development using DHA as standard. Experimental results conformed to the temperature-dependence theory of reaction rates, that for every 10° rise, the rate of reaction doubles. Curves of the absorbances at various times of incubation were calculated as percentiles of maximum color formation at each temperature. The interrelationship between 17-KS, 17-KGS, and DHA with respect to optimum reading time was noted. The significance of the finding that the rate of reaction of 17-KGS is much greater than that of 17-KS and DHA is demonstrated. Functional group contribution to the rate of reaction is discussed, as are other factors affecting the Zimmermann color reaction.

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Progress In The Practical Application Of Automated Image Analysis To Tem Negatives

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100078614 ◽

1977 ◽

Vol 35 ◽

pp. 214-217

Author(s):

F. A. Heckman ◽

E. Redman ◽

J.E. Connolly

Keyword(s):

Image Analysis ◽

Image Quality ◽

Exposure Time ◽

Image Contrast ◽

Automated Image Analysis ◽

Practical Application ◽

Factors Affecting ◽

High Image Quality ◽

Qualitative Evidence ◽

Comprehensive Study

In our initial publication on this subject1) we reported results demonstrating that contrast is the most important factor in producing the high image quality required for reliable image analysis. We also listed the factors which enhance contrast in order of the experimentally determined magnitude of their effect. The two most powerful factors affecting image contrast attainable with sheet film are beam intensity and KV. At that time we had only qualitative evidence for the ranking of enhancing factors. Later we carried out the densitometric measurements which led to the results outlined below.Meaningful evaluations of the cause-effect relationships among the considerable number of variables in preparing EM negatives depend on doing things in a systematic way, varying only one parameter at a time. Unless otherwise noted, we adhered to the following procedure evolved during our comprehensive study:Philips EM-300; 30μ objective aperature; magnification 7000- 12000X, exposure time 1 second, anti-contamination device operating.

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Factors affecting microstructural scale in liquid crystalline polymers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100174230 ◽

1990 ◽

Vol 48 (4) ◽

pp. 220-221

Author(s):

Christine M. Dannels ◽

Christopher Viney

Keyword(s):

Liquid Crystalline ◽

Liquid Crystalline Polymers ◽

Factors Affecting ◽

Crystalline Polymers ◽

Thermal Expansion Coefficients ◽

Low Thermal Expansion ◽

Lower Viscosity ◽

Fine Microstructure ◽

Planar Orientation ◽

Strength And Stiffness

Processing polymers from the liquid crystalline state offers several advantages compared to processing from conventional fluids. These include: better axial strength and stiffness in fibers, better planar orientation in films, lower viscosity during processing, low solidification shrinkage of injection moldings (thermotropic processing), and low thermal expansion coefficients. However, the compressive strength of the solid is disappointing. Previous efforts to improve this property have focussed on synthesizing stiffer molecules. The effect of microstructural scale has been overlooked, even though its relevance to the mechanical and physical properties of more traditional materials is well established. By analogy with the behavior of metals and ceramics, one would expect a fine microstructure (i..e. a high density of orientational defects) to be desirable.Also, because much microstructural detail in liquid crystalline polymers occurs on a scale close to the wavelength of light, light is scattered on passing through these materials.

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Factors affecting dentist participation in a state Medicaid program

Journal of Dental Education ◽

10.1002/j.0022-0337.1990.54.11.tb02476.x ◽

1990 ◽

Vol 54 (11) ◽

pp. 638-643 ◽

Cited By ~ 20

Author(s):

PC Damiano ◽

ER Brown ◽

JD Johnson ◽

JP Scheetz

Keyword(s):

Medicaid Program ◽

Factors Affecting

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Factors affecting dental utilization of elders aged 75 years or older

Journal of Dental Education ◽

10.1002/j.0022-0337.1986.50.11.tb02060.x ◽

1986 ◽

Vol 50 (11) ◽

pp. 673-677 ◽

Cited By ~ 5

Author(s):

AA Wilson ◽

LG Branch

Keyword(s):

Factors Affecting ◽

Dental Utilization

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Speech Therapy Services in a Large School System: A Six-Year Overview

Language Speech and Hearing Services in Schools ◽

10.1044/0161-1461.0704.207 ◽

1976 ◽

Vol 7 (4) ◽

pp. 207-219 ◽

Cited By ~ 3

Author(s):

Constance P. DesRoches

Keyword(s):

School System ◽

Speech Therapy ◽

Factors Affecting ◽

Case Load ◽

Number Of Children ◽

School Population ◽

System A ◽

Therapy Services ◽

And Shifts ◽

Selection Factors

A statistical review provides analysis of four years of speech therapy services of a suburban school system which can be used for comparison with other school system programs. Included are data on the percentages of the school population enrolled in therapy, the categories of disabilities and the number of children in each category, the sex and grade-level distribution of those in therapy, and shifts in case-load selection. Factors affecting changes in case-load profiles are identified and discussed.

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Assessing the Link Between Perception and Production in Cantonese Tone Acquisition

Journal of Speech Language and Hearing Research ◽

10.1044/2018_jslhr-s-17-0430 ◽

2019 ◽

Vol 62 (5) ◽

pp. 1243-1257 ◽

Cited By ~ 2

Author(s):

Peggy Pik Ki Mok ◽

Holly Sze Ho Fung ◽

Vivian Guo Li

Keyword(s):

Language Acquisition ◽

General Principle ◽

Choice Task ◽

Factors Affecting ◽

Tone Pair ◽

Tone Production ◽

Monosyllabic Words ◽

Early Production ◽

Forced Choice Task ◽

Production Accuracy

Purpose Previous studies showed early production precedes late perception in Cantonese tone acquisition, contrary to the general principle that perception precedes production in child language. How tone production and perception are linked in 1st language acquisition remains largely unknown. Our study revisited the acquisition of tone in Cantonese-speaking children, exploring the possible link between production and perception in 1st language acquisition. Method One hundred eleven Cantonese-speaking children aged between 2;0 and 6;0 (years;months) and 10 adolescent reference speakers participated in tone production and perception experiments. Production materials with 30 monosyllabic words were transcribed in filtered and unfiltered conditions by 2 native judges. Perception accuracy was based on a 2-alternative forced-choice task with pictures covering all possible tone pair contrasts. Results Children's accuracy of production and perception of all the 6 Cantonese tones was still not adultlike by age 6;0. Both production and perception accuracies matured with age. A weak positive link was found between the 2 accuracies. Mother's native language contributed to children's production accuracy. Conclusions Our findings show that production and perception abilities are associated in tone acquisition. Further study is needed to explore factors affecting production accuracy in children. Supplemental Material https://doi.org/10.23641/asha.7960826

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