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Fire can be thought of as any combustion process intense enough to emit light. It may be a quietly burning flame or the brilliant flash of an explosion. A typical combustion process is the burning of gasoline in an automobile engine. The vaporized fuel is mixed with air, compressed in the engine"s cylinder, and ignited by a spark. As the fuel flame up, the heat produced flows into the adjacent layer of unburned fuel and ignites it. In this way a zone of fire spreads throughout the fuel mixture is called a combustion wave. The speed at which such a combustion wave travels through a fuel mixture is called the burning velocity of the mixture. The burning velocity of a gas such as methane quietly burning in air is only about one foot per second. By comparison, the burning velocity of more reactive combinations such as the rocket Fuels, hydrogen and fluorine, can be hundreds of feet per second. If the fuel flows at the same speed as the combustion wave, the result is a stationary flame, like the one in your kitchen gas burner. In the kitchen burner a jet of gas mixed with airflows from the opening in the head of the burner. If the velocity of the fuel mixture flowing from the opening is greater than its burning velocity, the flame blows out. In jet engines speeding through the air at 500 to 600 miles per hour, the engine"s flame is sometimes blown out by the blast of air entering the combustion chamber at high speeds. Jet pilots call this condition "flameout". Combustion can sometimes occur very slowly. A familiar example of slow combustion is the drying of ordinary oil-based paint. In this chemical reaction, called oxidation, the oxygen in the air reacts with the drying oil in the paint to provide a tough film. The linseed oil molecules link together, forming an insoluble coating. How can the chemical reaction involved in such a quiet process as the drying of paint also produce spectacular flames and explosions The main difference between the two is the temperature at which they occur. At lower temperatures the reaction must take place over a long time. The heat which is slowly produced is dissipated to the surroundings and does not speed up the reaction. When the heat produced by the low-temperature reaction is retained instead of being dissipated, the system breaks into flame. In a flame or explosion, the reactions are extremely fast. In many chemical processes, however, such a rapid oxidation process would be extremely destructive. Which of the following could not be defined as combustion
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The importance and focus of the interview in the work of the print and broadcast journalist is reflected in several books that have been written on the topic. Most of these books as well as several chapters, mainly in, but not limited to, journalism and broadcasting handbooks and reporting texts, stress the "how to" aspects of journalistic interviewing rather than the conceptual aspects of the interview, its context, and implications. Much of the "how to" material is based on personal experiences and general impressions. As we know, in journalism as in other fields much can be learned from the systematic study of professional practice. Such study brings together evidence from which broad generalized principles can be developed. There is, as has been suggested, a growing body of research literature in journalism and broadcasting, but very little significant attention has been devoted to, the study of the interview itself. On the other hand, many general texts as well as numerous research articles on interviewing in fields other than journalism have been written. Many of these books and articles present the theoretical and empirical(经验的) aspects of the interview as well as the training of the interviewers. Unhappily, this plentiful general literature about interviewing pays little attention to the journalistic interview. The fact that the general literature on interviewing does not deal with the journalistic interview seems to be surprising for two reasons. First, it seems likely that most people in modern western societies are more familiar, at least in a positive manner, with journalistic interviewing than with any other form of interviewing. Most of us are probably somewhat familiar with the clinical interview, such as that conducted by physicians and psychologists. In these situations the professional person or interviewer is interested in getting information necessary for the diagnosis and treatment of the person seeking help. Another familiar situation is the job interview. However, very few of us have actually been interviewed personally by the mass media, particularly by television. And yet, we have a vivid acquaintance with the journalistic interview by virtue of our roles as readers, listeners, and viewers. Even so, tree understanding of the journalistic interview, especially television interviews, requires thoughtful analyses and study, as this book indicates. Much research has been done on interviews in general ______.
The 1990s have been designated the Decade Against Drug Abuse by the United Nations. But, (1)_____ less than three years to go before the end of the decade, governments and health organizations (2)_____ that they have made (3)_____ progress in reducing drug, alcohol and tobacco abuse. Today, consumption of all these substances is increasingly steadily worldwide. (4)_____ every country now has problems with (5)_____ drugs. And the world is producing and consuming more alcohol and tobacco than ever. Between 1970 and 1990 beer production (6)_____ rose by over 80 per cent. And, (7)_____ the number of smokers keeps on (8)_____,by the second or third (9)_____ of the next century there could be 10 million deaths each year (10)_____ smoking related illnesses. Drugs are also a huge burden (11)_____ the world economy. In the United States, for example, it"s estimated that alcohol and illegal drug use costs the country tens of billions of dollars each year, mainly (12)_____ health care. When the cost of tobacco related illnesses is added, (13)_____ total more than doubles. Drugs are also closely (14)_____ crime. Many police forces no longer (15)_____ between illegal and legal drugs when fighting crime. In Australia, for example, experts (16)_____ that police in some parts of the country spend between 70 and 80 percent of their time dealing with alcohol-related incidents. One explanation for the increase in drug (17)_____ is simply that people have more money to spend. Tobacco and alcohol companies are now (18)_____ much more on developing countries to take (19)_____ of greater wealth there. And criminals involved in the illegal drug trade are following (20)_____, introducing drugs into countries where they were previously hardly use.
A classic series of experiments to determine the effects of overpopulation on communities of rats was conducted by a psychologist, John Calhoun. In each experiment, an equal number of male and female adult rats were placed in an enclosure. The rat populations were allowed to increase. Calhoun knew from experience approximately how many rats could live in the enclosures without experiencing stress due to over crowding. He allowed the population to increase to approximately twice this number. Then he stabilized the population by removing offspring that were not dependent on their mothers. At the end of the experiments, Calhoun was able to conclude that overcrowding causes a break down in the normal social relationships among rats, a kind of social disease. The rats in the experiments did not follow the same patterns of behavior as rats would in a community without overcrowding. The females in the rat population were the most seriously affected by the high population density. For example, mothers sometimes abandoned their pups, and, without their mothers" care, the pups died. The experiments verified that in overpopulated communities, mother rats do not-behave normally. Their behavior may be considered diseased, pathological. The dominant males in the rat population were the least affected by overpopulation. Each of these strong males claimed an area of the enclosure as his own. Therefore, these individuals did not experience the overcrowding in the same way as the other rats did. However, dominant males did behave pathologically at times. Their antisocial behavior consisted of attacks on weaker male, female, and immature rats. This deviant behaviour showed that even though the dominant males had enough living space, they too were affected by the general overcrowding. Nondominant males in the experimental rat communities also exhibited deviant social behavior. Some withdrew completely, avoiding contact with other rats. Other nondominant males were hyperactive, chasing other rats and fighting each other. The behaviour of the rat population has parallels in human behavior. People in densely populated areas exhibit deviant behavior similar to that of the rats in Calhoun"s experiments. In large urban areas, such as New York City, London, and Cairo, there are abandoned children. There are cruel, powerful individuals, both men and women. There are also people who withdraw and people who become hyperactive. Is the principal cause of these disorders overpopulation Calhoun"s experiments suggest that it might be. In any case, social scientists and city planners have been influenced by the results of this series of experiments. The author implies that the behavior of the dominant male rats is sometimes parallel with that of ______.
The importance and focus of the interview in the work of the print and broadcast journalist is reflected in several books that have been written on the topic. Most of these books as well as several chapters, mainly in, but not limited to, journalism and broadcasting handbooks and reporting texts, stress the "how to" aspects of journalistic interviewing rather than the conceptual aspects of the interview, its context, and implications. Much of the "how to" material is based on personal experiences and general impressions. As we know, in journalism as in other fields much can be learned from the systematic study of professional practice. Such study brings together evidence from which broad generalized principles can be developed. There is, as has been suggested, a growing body of research literature in journalism and broadcasting, but very little significant attention has been devoted to, the study of the interview itself. On the other hand, many general texts as well as numerous research articles on interviewing in fields other than journalism have been written. Many of these books and articles present the theoretical and empirical(经验的) aspects of the interview as well as the training of the interviewers. Unhappily, this plentiful general literature about interviewing pays little attention to the journalistic interview. The fact that the general literature on interviewing does not deal with the journalistic interview seems to be surprising for two reasons. First, it seems likely that most people in modern western societies are more familiar, at least in a positive manner, with journalistic interviewing than with any other form of interviewing. Most of us are probably somewhat familiar with the clinical interview, such as that conducted by physicians and psychologists. In these situations the professional person or interviewer is interested in getting information necessary for the diagnosis and treatment of the person seeking help. Another familiar situation is the job interview. However, very few of us have actually been interviewed personally by the mass media, particularly by television. And yet, we have a vivid acquaintance with the journalistic interview by virtue of our roles as readers, listeners, and viewers. Even so, tree understanding of the journalistic interview, especially television interviews, requires thoughtful analyses and study, as this book indicates. The passage is most likely a part of ______.
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