scholarly journals Vitality Determinations of Tree Tissue with Kilocycle and Megacycle Electrical Impedance

1970 ◽  
Vol 46 (1) ◽  
pp. 63-64 ◽  
Author(s):  
C. Glerum
Keyword(s):  
Electrical Impedance ◽  
White Spruce ◽  
Red Pine ◽  
Living Tissue ◽  
Silver Maple ◽  
Before And After

Electrical impedance at one kilocycle and one megacycle frequency was measured on twigs of white spruce, red pine and silver maple, before and after freezing or boiling. The ratio of kilocycle over megacycle impedance ranged from 3.0 to 5.0 for living tissue, before treatment and from 1.1 to 1.6 for killed tissue, after treatment.

Prediction of Frost Hardiness in Douglas Fir Seedlings by Measuring Electrical Impedance in Stems at Different Frequencies

1973 ◽  
Vol 3 (2) ◽  
pp. 256-264 ◽  
Author(s):  
R. van den Driessche
Keyword(s):  
Survival Data ◽  
Electrical Impedance ◽  
Douglas Fir ◽  
Frost Hardiness ◽  
Impedance Measurements ◽  
Temperature Regimes ◽  
Before And After ◽  
Post Test ◽  
Different Levels ◽  
Short Days

Frost hardiness of Douglas fir (Pseudotsugamenziesii Mirb. Franco.) plants was assessed by a range of freezing tests in three experiments. In experiments 1 and 2 plants were grown in different temperature regimes, under short days, for 8 weeks to induce different levels of frost hardiness. In experiment 3, plants remained in the open and were sampled on 21 occasions through one year.Comparison of stem impedance measurements made at 1 kHz, 4.5 kHz, and 1 MHz, before and after freezing tests in experiments 1 and 2, indicated survival of individual plants was well predicted by post test measurements. The postfreezing test 1 kHz/1 MHz ratio distinguished between dead and surviving plants with the smallest number of measurements. Both this ratio and 4.5 kHz impedance provided similar conclusions about treatment effects, which agreed satisfactorily with conclusions from survival data. Impedance ratios of 1 kHz/1 MHz measured in stems after freezing tests accurately predicted survival in experiment 3. Seasonal changes in ratio, determined after freezing to a particular temperature, paralleled seasonal change in plant frost hardiness and was significantly correlated with exposure to cold during 14 days prior to measurement.

Soil chemistry changes after 27 years under four tree species in southern Ontario

1989 ◽  
Vol 19 (12) ◽  
pp. 1648-1650 ◽  
Author(s):  
Elizabeth Anne France ◽  
Dan Binkley ◽  
David Valentine
Keyword(s):  
Forest Floor ◽  
Soil Chemistry ◽  
Mineral Soil ◽  
White Spruce ◽  
Stand Development ◽  
Acid Neutralization ◽  
White Pine ◽  
Southern Ontario ◽  
Silver Maple ◽  
Paper Birch

After 27 years of stand development, the accumulated forest floor under replicated plots of white pine (Pinusstrobus L.), white spruce (Piceaglauca (Moench) Voss), paper birch (Betulapapyrifera Marsh.), and silver maple (Acersaccharinum L.) ranged from 240 g/m2 under maple to 3680 g/m2 under white pine. Forest floor pH ranged from a low under maple of 3.7 to a high under white spruce of 5.9. No significant differences were found in pH in 0–15 cm depth mineral soil; however, substantial differences in the acid neutralization capacities were evident among species, with soils under maple showing the lowest capacity to resist further acidification.

The dependence of electrical impedance of woody stems on various frequencies and tissues

1970 ◽  
Vol 48 (12) ◽  
pp. 2187-2192 ◽  
Author(s):  
C. Glerum ◽  
E. M. Krenciglowa
Keyword(s):  
Electrical Impedance ◽  
Low Frequencies ◽  
Before And After ◽  
Electrode Penetration ◽  
The Mean

The electrical impedance of 1-year-old twigs of three hardwoods and conifers was measured at several frequencies before and after boiling. In all species the impedance before killing decreased as frequency increased from 100 to 40 000 c.p.s. The rate of decrease in conifers was greater than in hardwoods, particularly at low frequencies. After the twigs were killed, the drastically reduced impedance exhibited only a slight dependence on frequency. The variability relative to the mean was about the same at all frequencies.The contribution of xylem and bark (i.e., periderm, phloem, and cambium combined) to the impedance was determined by measuring the impedance of the two tissues together and separately. The importance of uniform electrode penetration was demonstrated.

scholarly journals Apple Bruise Detection by Electrical Impedance Measurement

HortScience ◽  
2000 ◽  
Vol 35 (1) ◽  
pp. 104-107 ◽  
Author(s):  
Phillipa J. Jackson ◽  
F. Roger Harker
Keyword(s):  
Electrical Impedance ◽  
Impedance Measurement ◽  
Apple Fruit ◽  
Fruit Weight ◽  
Electrical Impedance Spectroscopy ◽  
Apple Cultivar ◽  
Impedance Measurements ◽  
Before And After ◽  
Electrical Impedance Measurement ◽  
Further Development

Electrical impedance was used to determine the extent of tissue damage that occurred as a result of bruising of apple fruit (Malus ×domestica Borkh, cvs. Granny Smith and Splendour). Impedance measurements were made before and after bruising. Plots of reactance against resistance at 36 spot frequencies between 50 Hz and 1 MHz traced a semicircular arc, which contracted in magnitude after bruising. A number of characteristics of these curves were then related to bruise weight. The change in resistance that occurred as a result of fruit impact (ΔR50Hz) was the best predictor of bruise weight, with r2 values up to 0.71. Before bruising, resistance of fruit was higher in `Splendour' than in `Granny Smith' (P < 0.001), and at 0 °C than at 20 °C (P < 0.001), but was not influenced by fruit weight. The influence of apple cultivar and temperature on electrical impedance may cause difficulties when implementing these measurements in a commercial situation. However, further development of electrical impedance spectroscopy methodologies may result in convenient research techniques for assessing bruise weight without having to wait for browning of the flesh.

scholarly journals Fabrication and Characterization of Bioglass

2018 ◽  
Vol 7 (2) ◽  
pp. 99-102
Author(s):  
Dalveer Singh ◽  
Sandeep Singh ◽  
Gurpreet Singh
Keyword(s):  
Glass Ceramics ◽  
Borosilicate Glasses ◽  
Living Tissue ◽  
Bioactive Glasses ◽  
Bioactive Properties ◽  
Amorphous Nature ◽  
Before And After ◽  
Fabrication And Characterization ◽  
New Generation

Glasses are common in use now days. These are used in different applications like domestic, automobile, telecommunication etc. The glasses are very useful materials because of their impressive properties. Few years back a new generation of glasses were developed i.e. bioactive glasses and bioactive glass ceramics. The glasses are used for bone grafting now-a-days because of their impressive bioactive properties. These glasses have tendency to form bonds with the living tissue organs. The future of these glasses will be bright in dental, orthopedics and prosthetic applications. In the present work borosilicate glasses of different compositions have been studied. The different elements were added with appropriate mol% to compose a new bioglass composition. The samples were prepared by melt quench route. The samples were immersed for 21 days in SBF. The samples were characterized before and after immersion in SBF by different techniques. The XRD technique was done to confirm the amorphous nature of glass before immersion and after immersion. The SEM and EDX were done to check the changes on the surface after immersion. The sample S1 has better biocompatibility results than S2 andS3. The formation of apatite on the glass samples were confirmed by all techniques mentioned above.

scholarly journals Methods for Successful Afforestation of a Weed Infested Clay Soil

1970 ◽  
Vol 46 (2) ◽  
pp. 139-143 ◽  
Author(s):  
F. W. Von Althen
Keyword(s):  
Weed Control ◽  
Clay Soil ◽  
Black Locust ◽  
Cost Benefit ◽  
White Spruce ◽  
White Pine ◽  
Southern Ontario ◽  
White Ash ◽  
Silver Maple ◽  
Hardwood Species

The effects of plowing and tilling, fertilization, and chemical weed control on survival and height growth of newly planted seedlings of black locust, silver maple, white ash, white pine, and white spruce were investigated in a non-replicated study in southern Ontario. Cost-benefit relationships of treatments were computed. Plowing and tilling improved growth of all species with average increases ranging from 37 per cent for white spruce to 750 per cent for white ash. Plowing and tilling plus weed control greatly improved growth of all hardwood species and resulted in the most favourable growth-cost relationship. Fertilization improved growth of locust, ash, and maple by 200, 500, and 700 per cent respectively, but failed to increase conifer growth. Application of 12 pounds of simazine increased ash mortality by 67 per cent. White spruce was subject to severe frost heaving following complete weed control.

Field Performance of Five Species in Four Different Containers in Maine

1989 ◽  
Vol 6 (4) ◽  
pp. 183-185
Author(s):  
David I. Maass ◽  
Andrea N. Colgan ◽  
N. Lynn Cochran ◽  
Carl L. Haag ◽  
James A. Hatch
Keyword(s):  
Norway Spruce ◽  
Black Spruce ◽  
Field Performance ◽  
White Spruce ◽  
Jack Pine ◽  
Red Pine ◽  
Conifer Species ◽  
Long Term Performance ◽  
Term Performance

Abstract Long-term performance of container-grown seedlings in Maine was unknown in the late 1970s. A study was established to test the performance of five conifer species: Norway, white and black spruce, and red and jack pine, grown in four containers of similar volume: Can-Am Multipot #1, Multipot #2, Japanese Paperpot FH408, and Styroblock 4. Seven years after outplanting, stem heights of jack pine and red pine were significantly greater for trees started in Multipot #2 containers. Three spruce species with the greatest growth were started in Multipot #1 containers. Paperpot seedlings ranked second in height for pines, Norway spruce, and white spruce; Styroblock 4's ranked last for all species. North. J. Appl. For. 6:183-185, December 1989.

Differential tolerance of coniferous species to the microbially produced herbicide bialaphos. II. Metabolic effects

1994 ◽  
Vol 24 (11) ◽  
pp. 2199-2207 ◽  
Author(s):  
Mikaĭlou Sy ◽  
Hank Margolis ◽  
De Yue ◽  
Robert Jobidon ◽  
Louis-P. Vézina
Keyword(s):  
Flux Density ◽  
White Spruce ◽  
Photosynthetic Photon Flux Density ◽  
Red Pine ◽  
Metabolic Effects ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Photosynthetic Photon Flux ◽  
Ammonium Accumulation ◽  
Higher Doses

The effect of the microbially produced herbicide bialaphos on ammonium accumulation and photosynthesis of white spruce (Piceaglauca (Moench) Voss) and red pine (Pinusresinosa Ait.) seedlings was studied under controlled environmental conditions. Ammonium accumulation increased markedly during the first 48 h for seedlings treated in June and was greater in red pine than in white spruce. Ammonium accumulation also increased with higher doses of bialaphos. In contrast, the accumulation of ammonium following bialaphos application in August was minimal for both species and for doses up to an equivalent of 3.0 kg active ingredient (bialaphos) per hectare. Continuous measurements of photosynthesis for the first 12 h following bialaphos application showed a slight negative effect of the herbicide on photosynthetic activity within 2 h of treatment. The decrease was greater for red pine than for white spruce. Photosynthesis measurements taken under three different levels of photosynthetic photon flux density 24 h after bialaphos application showed a greater decline with increasing photosynthetic photon flux density and with higher doses of bialaphos. Furthermore, the decline was greater in red pine than it was in white spruce. When photosynthesis was followed over a 7-day period, a large decrease was observed during the first 24 h, after which time photosynthesis stayed relatively constant. The decrease was greater with higher doses and was greater for red pine than for white spruce. There was a strong negative correlation between photosynthetic rate at day 7 and both the dose of bialaphos and the development of chlorotic foliage. These results help provide a physiological basis for understanding previously reported morphological and growth responses.

Étude du Matériel sur Pied Relatif et Ses Implications sur L'Aménagement des Plantations

1979 ◽  
Vol 55 (3) ◽  
pp. 95-101
Author(s):  
S. Popovich
Keyword(s):  
Initial Density ◽  
Stand Density ◽  
White Spruce ◽  
Red Pine ◽  
Pine Plantations ◽  
Plantation Management ◽  
Silvicultural Practices ◽  
Crucial Problem

Problems of plantation management and silvicultural practices in over- and under-stocked white spruce and red pine plantations are presented in the light of observations made while preparing normal yield tables. This study points out the crucial problem of initial density of man-made forests. For successful growth of light-demanding species such as pine, a minimum of 4 000-5 000 seedlings per hectare at planting are required. The use for stand density optimization is discussed.

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