scholarly journals II. On the influence of white light, of the different coloured rays and of darkness, on the development, growth, and nutrition of animals

1859 ◽  
Vol 9 ◽  
pp. 644-648
Keyword(s):  
White Light ◽  
Growth And Nutrition ◽  
Ordinary Light ◽  
Series Of Experiments

In this communication the author laid before the Society the particulars of a series of experiments, having for their object to discover what influence is exerted by ordinary light, by the different coloured rays, and by darkness on the development, growth, and nutrition of animals. After referring to the experiments of Edwards, Higginbottom, E. Forbes, Morren, Wöhler, Hannon, Moleschott, and Béclard, the results of which were shown to be somewhat contradictory, the author described the precautions taken by himself to avoid sources of fallacy.

scholarly journals III. On the influence of white light, of the different coloured rays and of darkness, on the development, growth, and nutrition of animals

1860 ◽  
Vol 10 ◽  
pp. 184-186
Keyword(s):  
White Light ◽  
Dark Cell ◽  
Black Glass ◽  
Growth And Nutrition

The apparatus used in the following experiments, was described in my Paper; but in the present instance, only two of the cells were employed, viz. that exposed to ordinary white light, and that from which all light is excluded. In order more effectually to prevent the possible admission of light, the following precautions were adopted with the dark cell:— 1. The perforated zinc floor was covered with thick brown paper. 2. The under surface of the lid was lined with black cloth, to secure accurate adjustment when shut, 3. The opaque black glass was covered with an additional coat of black oilpaint. 4. The lid was never opened in any light except that of a candle or of gas. March 20th, 1859.—A number of ova of the Silkworm ( Bombyxmori ), all of the same age, were placed in each of the two cells. No change was observed until May 18 th (sixty days after the commencement of the experiments), when one larva emerged from the ovum in each cell; and during twelve days, larvæ continued to emerge in the light and in the dark at the same rate.

scholarly journals On the luminosity curves of persons having normal and abnormal colour vision

1913 ◽  
Vol 88 (604) ◽  
pp. 404-428 ◽  
Keyword(s):  
White Light ◽  
Wave Length ◽  
Monochromatic Light ◽  
Absolute Intensity ◽  
White Patch ◽  
The Press ◽  
Colour Sense ◽  
Intimate Relation ◽  
Series Of Experiments ◽  
Pass Through

1. When reading a recent paper before the Royal Society, and also in the Press, Dr. Edridge Green has stated that he can find no connection between the luminosity and the colour sense of persons having either normal or abnormal colour sensations. Since I feel that to allow such a statement to go unchallenged might be interpreted as meaning that no such connection could be shown to exist, I propose in the following paper to place before the Society some of the evidence which indicated that there is in reality a very intimate relation between luminosity and colour sense. The results given include a small part of those which have been obtained in a series of experiments which have occupied the last two years and form part of investigation which is still in progress. The term “luminosity” as used in this paper has the following meaning: Suppose that light from some source, such as the electric arc, is admitted to a spectroscope by means of which a real pure spectrum is produced, and that a slide in the plane in which the spectrum is formed carries a slit of fixed width. Light of sensibly one wave-length, i. e. monochromatic light, will pass through this slit, and by means of a lens placed in the beam of this light an image of the first face of the prism which is used to from the spectrum can be formed on a screen. In this way a monochromatic patch of light is obtained, the brightness of which depends on the nature of the source of light, the width of the collimator slit, the width of the slit placed in the spectrum, which for short will be called the movable slit, and the dimensions of the lenses employed. Further, if alongside this coloured patch is formed a white patch of light produced by light which proceeds from the same source but has not undergone dispersion, and that by some means or other the intensity of this white light is altered till the coloured and white light, measured in any arbitrary units, measure the luminosity of the light of that colour which is passing through the movable slit. Since the unit in which the white light is measured is arbitrary, we are not concerned with the absolute intensity of illumination of the white patch, and may use any device we like to alter the quantity of white light which falls on the screen so long as we are able to measure the ratio of the quantity of light employed in different experiments. It will further be observed that for any given person the measurement of the luminosity of a given coloured light in the spectrum involves the comparsion of the brightness of the coloured patch as it appears to him with the brightness of the white patch as it appears to him.

scholarly journals INFLUENCE OF LIGHT ENVIRONMENT ON THE GROWTH OF HAIR IN NORMAL RABBITS WITH ESPECIAL REFERENCE TO THE ACTION OF NEON LIGHT

1928 ◽  
Vol 48 (1) ◽  
pp. 57-64 ◽  
Author(s):  
Wade H. Brown ◽  
Keyword(s):  
Environmental Conditions ◽  
Functional Activity ◽  
Proliferative Activity ◽  
Hair Follicles ◽  
Light Environment ◽  
Especial Reference ◽  
Growth And Nutrition ◽  
Complete Exclusion ◽  
Series Of Experiments

In a series of experiments dealing with the influence of light environment on normal rabbits, the growth of hair over shaved areas was used as an index of functional activity. The conditions compared were exposure to neon light, complete exclusion of light, and exposure to diffuse, filtered sunlight of varying intensity. It was found that prolonged existence under these conditions affected the proliferative activity of hair follicles in a manner and to an extent comparable with the effects produced by the same environmental conditions on the growth and nutrition of the animals themselves.

scholarly journals Experimental Tree Planting on U.K. Containment Landfill Sites: Results of 10 Years’ Monitoring

2008 ◽  
Vol 34 (3) ◽  
pp. 163-172
Author(s):  
Andy Moffat ◽  
Kirsten Foot ◽  
Fiona Kennedy ◽  
Martin Dobson ◽  
Geoff Morgan
Keyword(s):  
Tree Species ◽  
Landfill Gas ◽  
Survival Rates ◽  
Tree Planting ◽  
White Poplar ◽  
Silver Maple ◽  
Growth And Nutrition ◽  
Landfill Sites ◽  
Series Of Experiments ◽  
Set Up

A series of experiments was set up in England in the early 1990s on five containment landfill sites engineered to modern standards to test the relative performance of 14 native and nonnative woodland tree species. This article describes the results of monitoring their survival, growth, and nutrition over a 10-year period. The experiments demonstrated that several species, notably ash, whitebeam, white poplar, and wild cherry, can usually be established on landfill sites with survival rates comparable to other brownfield sites. Despite general site infertility, growth of many tree species (for example, ash, beech, English oak, sycamore, Italian alder, silver maple, white poplar, and whitebeam) was similar to that expected on greenfield sites in the locality of the landfill sites. As well as infertility, soil droughtiness and mammal browsing were identified as limiting tree performance of particular species on some sites. After 10 years, there was no evidence of interaction with landfill containment systems or landfill gas.

scholarly journals The selective photochemical action of polarised light.—I. The hydrolysis of starch

1924 ◽  
Vol 97 (682) ◽  
pp. 250-253 ◽  
Keyword(s):  
Food Material ◽  
Filament Lamp ◽  
Polarised Light ◽  
Ordinary Light ◽  
Series Of Experiments ◽  
Living Leaf ◽  
Microscope Slides ◽  
Hydrolysis Of ◽  
Reserve Food

In some experiments carried out during the summer of 1921, on the effect of different kinds of light on the growth of plants, it was found that plane-polarised light causes a marked acceleration in seed germination and in the formation of flowers, but that no effect was noticed on the vegetative growth of the stem and leaves. Since the first two processes involve a hydrolysis of reserve food material, some experiments have been carried out on the hydrolysis of starch in heterogeneous light, and in plane-polarised light, in order to determine whether any selective action of the latter can be observed in vitro . In this connection it is interesting to note that in the living leaf the starch synthesised during the day undergoes hydrolysis to sugars in the early evening, when, as is well known, the light from the sky is polarised. The results obtained would seem to show that plane-polarised light exerts very definitely a selective photochemical effect compared with ordinary light. Two series of experiments on the photochemical hydrolysis of starch have been carried out, one with daylight and the other with artificial light from an ordinary Osram filament lamp. In both series carefully purified starch grains were mounted on microscope slides in the presence of weak enzyme solution.

FeXIV Line Emission Polarization of the July 11, 1991 Solar Corona

1994 ◽  
Vol 144 ◽  
pp. 541-547
Author(s):  
J. Sýkora ◽  
J. Rybák ◽  
P. Ambrož
Keyword(s):  
High Resolution ◽  
Solar Corona ◽  
Emission Line ◽  
Solar Eclipse ◽  
White Light ◽  
Preliminary Analysis ◽  
Line Emission ◽  
Total Solar Eclipse ◽  
Degree Of Polarization ◽  
High Resolution Images

AbstractHigh resolution images, obtained during July 11, 1991 total solar eclipse, allowed us to estimate the degree of solar corona polarization in the light of FeXIV 530.3 nm emission line and in the white light, as well. Very preliminary analysis reveals remarkable differences in the degree of polarization for both sets of data, particularly as for level of polarization and its distribution around the Sun’s limb.

White-Light Coronal Structures: Streamers and CMEs

1994 ◽  
Vol 144 ◽  
pp. 82
Author(s):  
E. Hildner
Keyword(s):  
Emission Line ◽  
Electron Density ◽  
White Light ◽  
Coronal Mass Ejections ◽  
X Rays ◽  
Solar Cycles ◽  
Temperature Function ◽  
X Ray ◽  
Eclipse Observations ◽  
Coronal Structures

AbstractOver the last twenty years, orbiting coronagraphs have vastly increased the amount of observational material for the whitelight corona. Spanning almost two solar cycles, and augmented by ground-based K-coronameter, emission-line, and eclipse observations, these data allow us to assess,inter alia: the typical and atypical behavior of the corona; how the corona evolves on time scales from minutes to a decade; and (in some respects) the relation between photospheric, coronal, and interplanetary features. This talk will review recent results on these three topics. A remark or two will attempt to relate the whitelight corona between 1.5 and 6 R⊙to the corona seen at lower altitudes in soft X-rays (e.g., with Yohkoh). The whitelight emission depends only on integrated electron density independent of temperature, whereas the soft X-ray emission depends upon the integral of electron density squared times a temperature function. The properties of coronal mass ejections (CMEs) will be reviewed briefly and their relationships to other solar and interplanetary phenomena will be noted.

Periodic Variations in the Coronal Green Line Intensity and their Connection with the White-light Coronal Structures

2000 ◽  
Vol 179 ◽  
pp. 197-200
Author(s):  
Milan Minarovjech ◽  
Milan Rybanský ◽  
Vojtech Rušin
Keyword(s):  
Time Resolution ◽  
White Light ◽  
Short Time Scale ◽  
High Time Resolution ◽  
Green Line ◽  
Periodic Intensity ◽  
Coronal Green Line ◽  
Significant Intensity ◽  
Short Time ◽  
Coronal Structures

AbstractWe present an analysis of short time-scale intensity variations in the coronal green line as obtained with high time resolution observations. The observed data can be divided into two groups. The first one shows periodic intensity variations with a period of 5 min. the second one does not show any significant intensity variations. We studied the relation between regions of coronal intensity oscillations and the shape of white-light coronal structures. We found that the coronal green-line oscillations occur mainly in regions where open white-light coronal structures are located.

X-ray microanalysis of thin specimens in the transmission electron microscope at voltages up to 1000 Kv.

1978 ◽  
Vol 36 (1) ◽  
pp. 540-541
Author(s):  
G. Cliff ◽  
M.J. Nasir ◽  
G.W. Lorimer ◽  
N. Ridley
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Weight Fraction ◽  
Present Series ◽  
Constant Independent ◽  
X Ray ◽  
Transmission Electron ◽  
Series Of Experiments ◽  
Image Position ◽  
X Ray Absorption

In a specimen which is transmission thin to 100 kV electrons - a sample in which X-ray absorption is so insignificant that it can be neglected and where fluorescence effects can generally be ignored (1,2) - a ratio of characteristic X-ray intensities, I1/I2 can be converted into a weight fraction ratio, C1/C2, using the equationwhere k12 is, at a given voltage, a constant independent of composition or thickness, k12 values can be determined experimentally from thin standards (3) or calculated (4,6). Both experimental and calculated k12 values have been obtained for K(11<Z>19),kα(Z>19) and some Lα radiation (3,6) at 100 kV. The object of the present series of experiments was to experimentally determine k12 values at voltages between 200 and 1000 kV and to compare these with calculated values.The experiments were carried out on an AEI-EM7 HVEM fitted with an energy dispersive X-ray detector.

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