Testing and classification of individual plants for fire behaviour: plant selection for the wildland - urban interface

Knowledge of how species differ in their flammability characteristics is needed to develop more reliable lists of plants recommended for landscaping homes in the wildland–urban interface (WUI). As indicated by conflicting advice in such lists, such characterisation is not without difficulties and disagreements. The flammability of vegetation is often described as having four components (ignitability, combustibility, sustainability and consumability). No standards or generally recognised test procedures exist for evaluating these components in plants. Some measurements of flammability include times for ignition, rate of flame spread, flame height and heat release rate. Often, the fire behaviour characteristics of a plant are derived from its physical and chemical characteristics. Thermogravimetric analysis and other thermal analyses of ground samples have long been used to characterise the thermal degradation of vegetation. More recently, researchers have used the oxygen consumption methodology to measure the heat released due to combustion of the vegetation. Although oxygen consumption calorimetry is an improvement in characterising plant flammability, translation of laboratory results to field conditions can be problematic and tests can be expensive.

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Physical and Chemical Characteristics of Cultus Lake, British Columbia.

Journal of the Biological Board of Canada ◽

10.1139/f37-022 ◽

1937 ◽

Vol 3 (4) ◽

pp. 363-402 ◽

Cited By ~ 8

Author(s):

William E. Ricker

Keyword(s):

Oxygen Consumption ◽

Oxygen Content ◽

Heat Budget ◽

Clear Lake ◽

Equable Climate ◽

Low Degree ◽

Seasonal Circulation ◽

Measure Oxygen Consumption ◽

Physical And Chemical

Cultus lake is a rather small, fairly deep, clear lake of the western Cascade mountains, and is the home of one of the populations of Fraser river sockeye. The equable climate of the region is reflected in the low annual heat budget of the lake and its normal lack of an ice cover in winter, with continued complete or partial circulation of its water throughout that season. Judged by the low degree of hypolimnial oxygen consumption in summer, the lake is to be classed as distinctly oligotrophic. The oxygen content at all depths and seasons is sufficient for the respiration of salmonoid fishes. The water is moderately hard and slightly alkaline. Quantities of dissolved nitrates and phosphates in the water appear to be of the order characteristic of oligotrophic lakes. Silicates are present much in excess of the requirements of the lake's diatom populations. The number of adult sockeye returning to the lake in normal years is insufficient to add to its supply of nutritive salts in significant amount. Temperature observations and oxygen determinations, taken at frequent intervals for several years, have contributed to the knowledge of certain questions of general limnological interest. Such include (1) the manner in which the hypolimnion of a lake is warmed in summer; (2) the classification of the seasonal circulation periods in temperate lakes; and (3) the oxygen content of a lake at the close of vernal circulation, and its use as a standard from which to measure oxygen consumption throughout the summer.

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Detailed Derivations of Formulas for Heat Release Rate Calculations Revisited: A Pedagogical and Systematic Approach

Journal of Research of the National Institute of Standards and Technology ◽

10.6028/jres.124.016 ◽

2019 ◽

Vol 124 ◽

Author(s):

Jiann C. Yang

Keyword(s):

Oxygen Consumption ◽

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Chemical Engineering ◽

Chemical Species ◽

Flow Process ◽

Generalized Framework ◽

Oxygen Consumption Calorimetry ◽

Engineering Practices

The derivations of the formulas for heat release rate calculations are revisited based on the oxygen consumption principle. A systematic, structured, and pedagogical approach to formulate the problem and derive the generalized formulas with fewer assumptions is used. The operation of oxygen consumption calorimetry is treated as a chemical flow process, the problem is formulated in matrix notation, and the associated material balances using the tie component concept commonly used in chemical engineering practices are solved. The derivation procedure described is intuitive and easy to follow. Inclusion of other chemical species in the measurements and calculations can be easily implemented using the generalized framework developed here.

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A potential antiviral and food-derived healthy ingredient: Resveratrol

Food and Health ◽

10.3153/fh21007 ◽

2021 ◽

Vol 7 (1) ◽

pp. 54-63

Author(s):

Ayla Arslaner ◽

Zehra Türkoğlu

Keyword(s):

Carbon Number ◽

Chemical Properties ◽

Physical And Chemical Properties ◽

Food Ingredient ◽

Beneficial Effects ◽

Antiviral Effects ◽

Natural Polyphenol ◽

Physical And Chemical ◽

And Chemical Properties

Polyphenols are the secondary metabolites of plants and has an important role in human nutrition as the leading antioxidants. According to the carbon number-based classification of polyphenols, resveratrol is a natural polyphenol in the stilbene group with antioxidant and anticarcinogenic effects. Its beneficial effects on cardiovascular diseases have also been reported. It was first identified in 1940 and has recently gained importance especially in medicine and pharmacy. Researchers have carried out various studies on resveratrol and its time-honored use in traditional eastern medicine has been reported. Resveratrol is a food ingredient that has the potential to be used in the treatment of various diseases, but also has antiviral effects. The study focuses on resveratrol’s physical and chemical properties, effects on health, antiviral effects and use in foods as a functional component.

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A review of the classification of nonstrabismic binocular vision anomalies

Optometry Reports ◽

10.4081/optometry.2016.5626 ◽

2016 ◽

Vol 5 (1) ◽

Cited By ~ 1

Author(s):

Charles Darko-Takyi ◽

Naimah Ebrahim Khan ◽

Urvashni Nirghin

Keyword(s):

Binocular Vision ◽

Systemic Disease ◽

Clinical Signs ◽

Review Literature ◽

Test Procedures ◽

Convergence Insufficiency ◽

Different Types ◽

Proper Diagnosis ◽

Divergence Insufficiency

There are conflicting and confusing ideas in literature on the different types of accommodative and vergence anomalies as different authors turn to classify them differently. This paper sought to review literature on the different classifications and types of nonstrabismic binocular vision anomalies and harmonize these classifications. Search engines, namely Google scholar, Medline, Cinahl and Francis databases, were used to review literature on the classification of accommodative and vergence dysfunctions using keywords like binocular vision dysfunctions, classification of nonstrabismic binocular vision disorders or anomalies, accommodative disorders/anomalies classification and vergence disorders/anomalies classifications, and included works that described these anomalies. Nonstrabismic binocular vision anomalies are classified as accommodative and vergence anomalies. There are three different major types of accommodative anomalies, namely accommodative insufficiency, accommodative infacility (accommodative inertia), and accommodative excess (accommodative spasm), and seven different types of vergence anomalies (convergence insufficiency, convergence excess, divergence insufficiency, divergence excess, basic esophoria, basic exophoria and fusional vergence dysfunctions), which are functional in origin. Functionally, there is a commonly reported interaction between accommodative and convergence insufficiency referred to as pseudoconvergence insufficiency. Accommodative paralysis (subtype of accommodative insufficiency) and vergence anomalies – i.e., convergence paralysis, convergence spasm and divergence paralysis – are non-functional in origin with underlying systemic disease etiologies. Systemic convergence insufficiency, associated with subnormal accommodation, is a non-functional interaction between the accommodative and convergence insufficiency. The classification of nonstrabismic binocular vision anomalies is based on the description of the clinical signs and the underlying etiology either functional or non-functional in origin. Proper diagnosis and management involves investigation of the underlying etiology in addition to the battery of binocular vision test procedures.

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