Emerging Indoor Air Quality Issues In Developing Countries

indoor air quality
In terms of aggregate health effects, household solid fuel use is currently the most important source of indoor air pollution in developing countries. Although relatively equitable economic and rural development has contributed to reducing the use of solid fuels in some settings (e.g., in some newly industrialized Asian countries), indoor air pollution is likely to remain an important health risk in poorer developing countries in the absence of successful intervention programs. More broadly, indoor air quality issues in developing countries are dynamic phenomena that require dynamic research and policy responses. (more…)

Health Effects Of Exposure To Indoor Smoke

indoors smoke
Exposure to indoor air pollution from the combustion of solid fuels has been implicated, with varying degrees of evidence, as a causal agent of several diseases in developing countries. In a review of the epidemiological evidence for the health effects of indoor smoke from solid fuels, Bruce et al. concluded that, despite some methodological limitations, epidemiological studies provide compelling evidence of causality for acute respiratory infections (ARI) and chronic obstructive pulmonary disease (COPD). This is reinforced by experimental data, studies of pathogenesis, and indirect evidence from environmental tobacco smoke (ETS) and ambient air pollution studies. (more…)

Reducing Indoor Air Pollution in Developing Countries

indoor air pollution
Important research over the past few decades has illustrated that indoor air pollution and indoor smoke from solid fuel poses important health risks in developing countries. Unfortunately, affordable and effective interventions for reducing these risks are limited. This may be because in designing new interventions, the complexities of household energy use and exposure have been often overlooked, and there is a lack of infrastructure to support technological innovations, marketing and dissemination, and maintenance. Even less is known about combinations of technologies that may be used in a household and the factors that motivate the households to adopt them. (more…)

Health Benefits Of Household Energy Transitions

household energy consumption
Reducing exposure to indoor air pollution from household energy use can be achieved through interventions in of the following areas:

* Emissions source and energy technology (fuel– stove combination).
* Housing design and ventilation.
* Behavior and time–activity budget. (more…)

Photo-Electrochemical Energy Conversion Device

The basic processes that occur in such a system are well understood. The semiconductor electrode efficiently absorbs light, producing an excited electronic state. In this excited state, the electron and the electron vacancy (the ‘‘hole’’) are both more energetic than they were in their respective ground states. The photo-excited electrons and holes are generally not tightly bound to an individual atom or set of atoms in the solid. (more…)

Acid Deposition Effects: Aquatic and Terrestrial Acid Rains

Effects Of Acid Deposition
Acid deposition and the associated particulate nitrates and sulfates are implicated in the deterioration of certain sensitive ecosystems, decreased visibility, negative human health effects, and increased degradation of certain stone building materials and cultural resources, especially those made of limestone and marble. Fine particulate nitrate and sulfate particles associated with acid deposition are implicated in aggravating cardiorespiratory diseases such as asthma and chronic bronchitis, especially in urban areas. In many cases estimating the impact of acid deposition on various ecosystems can be a difficult process because acid deposition is only one of many impacts that can effect a response. However, wet and dry acid deposition has been documented as a major factor in the following ecosystem responses. (more…)

Acidic Deposition Formation and Trends of Acid Rains

Acidic Deposition
The formation of acidic deposition is largely from the combustion of fossil fuels and the smelting of sulfide ores. Minor natural sources exist such as the formation of hydrochloric and sulfuric acid from gaseous volcanic eruptions.

There are well over 100 gaseous and aqueous phase reactions that can lead to acid formation and more than fifty oxidizing agents and catalysts may be involved. However, in the simplest terms sulfur in fuels is oxidized to SO2 , and SO2 in the atmosphere is further oxidized and hydrolyzed to sulfuric acid. Most nitric acid is formed by the fixation of atmospheric nitrogen gas (N2) to NOx (NO and NO2) during high temperature combustion emissions, followed by further oxidation and hydrolysis that produces nitric acid in the atmosphere. (more…)

Peak Electricity Demand Impact and Reducing Power Needs During Peak Periods

Peak Electricity Demand
Power generation and distribution networks are built with spare capacity to meet peak periods of energy consumption is usually a time when demand for heating and / or cooling is particularly acute accommodate. Normally, peak electricity demand in some cases last just a few hours every year. And while the networks have always had to cope with peaks in recent years, the electricity consumption during peak hours has increased dramatically in the afternoon. (more…)

Human Exposure To Indoor Smoke From Solid Fuels

smoke solid fuels
Exposure to air pollutants and air pollution problem are very high in indoor environments in developing countries. Smith has estimated that at the aggregate level (i.e., without accounting for particle size, chemical composition, and source), approximately 80% of total global exposure to airborne particulate matter occurs indoors in developing nations. Details of exposure for various household members, and the roles of both pollution and behavior (e.g., location with respect to stove and activities), have been studied and evaluated using new tools and technology. (more…)

Mechanical Pulp Paper Production

Most discussions of energy use in paper production and papermaking are confusing because of a failure to define exactly what is meant by energy. It is important to keep track of the form in which energy is used. The major inputs to a paper mill are wood, purchased energy in the form of electricity and fossil fuels, and water. Some components of the wood are used as a raw material and some as by-product fuel. What the industry generally reports is the process energy use at the mill, which is the sum of the purchased energy and the process by-product energy (part of the energy originally in the wood) that is used. (more…)

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