Combustion of plant material

Wood of this Handbook, not only determined by bomb calorimetry but also by DTA and DSC. 

Kriebitzsch [77] determined the net primary production (NPP) of two light and two shadow plant species by means of bomb calorimetry and calculated their efficiencies as percentage of energy fixed in dry matter related to solar radiation energy. Efficiency was more homogeneous among the four species in a shaded area (0.9 to 2.2 %) than in the open field (0.4 to 2.7 %) with a maximum NPP of about 860 MJ/(ha.d). 

Collin and Jones [78] investigated the caloric content of pollen from wind- and insect-pollinated dicotyles and of wind-pollinated monocotyles and found no sig- 

It was supposed that the thick lipophilic resin layer (20 % dm) on the leaves of the fire-adapted species Elytropappus rhinocerotis from the Cape Province/South Africa is connected with the well-known flammability of this plant. Proksch and coworkers [79] could show by bomb calorimetry that the caloric value of the resin alone is 13 89 kJ/g, of the resin per g branch 2.78 kJ/g and that of young branches 21.81 kJ/g. Therefore, the authors suggest that the high flammability is due to the fine branch structures and the dense growth rather than to the contribution of this non-volatile resin. 

Hellmold and Schmidt [81] determined the calonc content of the four most important plant species in a species-rich beech forest on calcareous soil and found values of 16.1 to 19.1 kJ/g for the surface part and of 16.9 to 18.5 kJ/g for rhizomes and roots. While the energy content of leaves and shoots decreased during the season the underground part increased its caloric value. Largest values were 

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Plant Residues. The paraquat residues in Cannabis plants at differ-ent times after application and the percent of i C extract with ethyl acetate and methanol are shown in Table I. Combustion of plant material harvested at 29 h showed a significant loss of C (69%) when compared to time 0. The amount of C extracted with methanol also exhibited a decline with time, particularly at 29 h. Vincent et al. (8) have also observed a similar loss of paraquat residues on the same collection of Cannabis, using a residue method based on sodium dithioate reduction of the extracted paraquat, followed by spectrophotometric analysis. Attempts to examine the possible production of labeled products by thin-layer chromatography on cellulose-coated plates with several solvent systems have been unsuccessful to date due to the high ratio of plant material to labeled paraquat in the samples. The plant residues measured in the present study would appear to be consistent with mean values (331 ppm) found in 20 confiscated marihuana samples reported by Turner et al. (9), although there was considerable variation (2-2264 ppm) in the confiscated samples. 

The tradition of repelling insects by burning plants is still strongly upheld in many countries, and the popularity of repellent smoke probably lies in its convenience. As most households in the developing world use a wood-smoke cooking fire, the addition of plants requires minimum effort. Similarly, mosquito coils are the preferred antimosquito product used by low-income communities"" because of their convenience and effectiveness."" For those with low household income, the utilization of waste products such as coconut husks maximizes the usefulness of a resource. However, these methods are only suitable for use outdoors because the combustion of plant materials releases many small particles and gases that have negative effects on human health." ... 

A. There are no known health problems from oral Salvia use. However, it is known that smoking tobacco is damaging to your lungs and may cause cancer, emphysema, bronchitis, stroke and cardiovascular disease. These toxic side-effects of tobacco smoking are not due mainly to nicotine but rather to combustion products (tars and carbon monoxide), which are present whenever any type of plant material (e.g. Salvia) is smoked. Common sense will tell you that smoking Salvia, or any material, can be bad for your health. It is not known if Salvia can cause birth defects, but it is prudent to assume that it could. 

ASH. (1) In analytical chemistry the residue remaining after complete combustion of a material. It consists of mineral matter (silica, alumina, iron oxide, etc.), the amount often being a specification requirement. (2) The end product of large-scale coal combustion as in power plants now said to be the sixth most plentiful mineral in the U.S. It consists principally of fly ash, bottom ash, and boiler ash. Some of its values are recoverable, and there are a number of industrial uses of fly ash, e.g., in cement products and road rill. 

In the pure form, CDDs are colorless solids or crystals. CDDs enter the environment as mixtures containing a variety of individual components and impurities. In the environment they tend to be associated with ash, soil, or any surface with a high organic content, such as plant leaves. In air and water, a portion of the CDDs may be found in the vapor or dissolved state, depending on the amount of particulate matter, temperature, and other environmental factors. 2,3,7,8-TCDD is odorless. The odors of the other CDDs are not known. CDDs are known to occur naturally, and are also produced by human activities. They are naturally produced from the incomplete combustion of organic material by forest fires or volcanic activity. CDDs are not intentionally manufactured by industry, except in small amounts for research purposes. They are unintentionally produced by industrial, municipal, and domestic incineration and combustion processes. Currently, it is believed that CDD emissions associated with human incineration and combustion activities are the predominant environmental source. 

Waste-treatment processes commonly result in the production of solid wastes that must be disposed of safely. Enzymatic treatment is no exception. For example, although enzymatic treatment may not produce as large a quantity of solid products as does biological treatment, some solid residues may be formed, e.g., the polymer precipitates formed during the treatment of phenols with peroxidases, spent adsorbents such as talc, chitin, or activated carbon that are used to eliminate the soluble products of enzymatic reactions, or residues of plant materials such as raw soybean hulls when they are used in place of purified enzymes during treatment. Perhaps, the polymers and adsorbents could be incinerated to recover some energy if the emission of dangerous combustion by-products can be controlled or prevented. The residues of plant materials could potentially be composted and used as soil conditioners, provided that pollutants do not leach from them at substantial rates. To date, none of these disposal problems have been addressed adequately. 

The different size modes reflect differences in particle sources, transformations, and sinks (Finlayson-Pitts and Pitts 2000). For example, coarse particles are generated by mechanical processes such as wind erosion of soil, wave action in the oceans, and abrasion of plant material. In contrast, many of the fine particles in the atmosphere are produced from either primary emissions from combustion sources or via atmospheric gas-to-particle conversions (i.e., new particle formation). The relative and absolute sizes of particle modes, as well as the number of modes, can vary greatly in different locations and at different times. In addition, the chemical composition of particles within one size... 

Coal is an organic sedimentary rock that is formed from the accumulation and preservation of plant materials, usually in a swamp environment. Coal is a combustible rock, and along with petroleum and natural gas it is one of the three most important fossil fuels, such as for the generation of electricity. 

First is classification highlighting natural origin and following the anatomical order of plants, thus dividing plant substances into materials stemming from such parts of plants as the root, bark, stem, leaves, and flowers. Second is classification highlighting the usefiil properties of plant materials to form classes such as vegetable nutriment, medicines, combustible materials, textiles, fermentable materials, and... 

Carbon dioxide, COj. Sublimes — 78 5 C. A colourless gas at room temperature, occurs naturally and plays an important part in animal and plant respiration. Produced by the complete combustion of carbon-containing materials (industrially from flue gases and from synthesis gas used in ammonia production) and by heating metal carbonates or by... 

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