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Natural Gas 1. Natural gas is produced from reservoirs deep beneath the earth’s surface. It is a fossil fuel, meaning that it is derived from organic material buried in the earth millions of years ago. The main component of natural gas is methane. 2. The popularity and use of clean natural gas has increased dramatically over the past 50 years as pipeline infrastructure has been installed to deliver it conveniently and economically to millions of residential, commercial and industrial customers worldwide. Today, natural gas services available in all 50 states in the U.S., and is the leading energy choice for fueling American homes and industries. More than 65 million American homes use natural gas. In fact, natural gas is the most economical source for home energy needs, costing one-third as much as electricity. In addition to heating homes, much of the gas used in the United States is used as a raw material to manufacture a wide variety of products, from paint to fibers for clothing, to plastics for healthcare, computing and furnishings. Natural gas is also used in a significant number of new electricity-generating power plants. 3. Natural gas is one of the safest and cleanest fuels available. It emits less pollution than other fossil fuel sources. When natural gas is burned, it produces mostly carbon dioxide and water vapour—the same substances emitted when humans exhale. Compared with some other fossil fuels, natural gas emits the least amount of carbon dioxide into the air when combusted, making natural gas the cleanest burning fossil fuel of all. 4. The United States consumes about one-third of the world’s natural gas output, making it the largest gas-consuming region in the world. The U.S. Department of Energy Information Administration forecasts that natural gas demand will grow by more than 50 percent by 2025. 5. There are huge reserves of natural gas beneath the earth’s surface. The largest reserves of natural gas can be found in Russia, West and North Africa and the Middle East. LNG has been produced domestically and imported in the United States for more than four decades. Today, the leading imports of LNG are Japan, Korea, France and Spain. Paragraph 3 ______.
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Obtaining Drinking Water from Air Humidity Not a plant to be seen, the desert ground is too dry. But the air contains water, and research scientists have found a 1 of obtaining drinking water from air humidity. The system is based completely on renewable energy and is therefore autonomous. Cracks permeate the dried-out desert ground and the landscape bears testimony to the lack of water. But even here, where there are no lakes, rivers or groundwater, considerable quantities of water are stored in the air. In the Negev desert in Israel, for example, annual average relative air humidity is 64 percent-in every cubic meter of air there are 11.5 milliliters of water. German research scientists have found a way of converting this air humidity autonomously into drinkable water. "The process we have developed is based exclusively on renewable energy sources 2 thermal solar collectors and photovoltaic ceils, 3 makes this method completely energy-autonomous. It will 4 function in regions where there is no electrical infrastructure." says Siegfried Egner, head of the research team. The principle of the 5 is as follows: hygroscopic brine-saline solution which absorbs moistureruns down a tower-shaped unit and absorbs water from the air. It is then sucked 6 a tank a few meters off the ground in which a vacuum prevails. Energy from solar collectors 7 up the brine, which his diluted by the water it has 8 . Because of the vacuum, the boiling point of the liquid is lower than it would be under 9 atmospheric pressure. This effect is known from the mountains: as the atmospheric pressure there is lower than in the valley, water boils at temperatures distinctly below 100℃. The evaporated, non-saline water is condensed and runs down through a completely filled tube in a controlled manner. The gravity of this water column 10 produces the vacuum and so a vacuum pump is not needed. The reconcentrated brine 11 down the tower surface again to absorb moisture from the air. "The concept is suitable for various water 12 . Single-person units and plants supplying water to entire hotels are conceivable, " says Egner. Prototypes have been built for 13 system components-air moisture absorption and vacuum evaporation-and the research scientists have already 14 their interplay on a laboratory scale. In a further 15 the researchers intend to develop a demonstration facility.
Students Learn Better with Touchscreen Desks Observe the criticisms of nearly any major public education system in the world, and a few of the many complaints are more or less universal. Technology moves faster than the education system. Teachers must teach at the pace of the slowest student rather than the fastest. And—particularly in the United States—grade school children as a group don’t care much for, or excel at, mathematics. So it’s heartening to learn that a new kind of "classroom of the future" shows promise at mitigating some of these problems, starting with that fundamental piece of classroom furniture: the desk. AUK study involving roughly 400 students, mostly aged 8-10 years, and a new generation of multi- touch, multi-user, computerized desktop surfaces is showing that over the last three years the technology has appreciably boosted students’ math skills compared to peers learning the same material via the conventional paper-and-pencil method. How Through collaboration, mostly, as well as by giving teachers better tools by which to micromanage individual students who need some extra instruction while allowing the rest of the class to continue moving forward. Science, Clay Dillow, classroom of the future, education, engineering, math, mathematics, Synergy Net Traditional instruction still shows respectable efficacy at increasing students fluency in mathematics, essentially through memorization and practice—dull, repetitive practice. But the researchers have concluded that these new touch screen desks boost both fluency and flexibility—the critical thinking skills that allow students to solve complex problems not simply through knowing formulas and devices, but by being able to figure out what there all problem is and the most effective means of stripping it down and solving it. One reason for this, the researchers say, is the multi-touch aspect of the technology. Students working in the next-gen classroom can work together at the same tabletop, each of them contributing and engaging with the problem as part of a group. Known as Synergy Net, the software uses computer vision systems that see in the infrared spectrum to distinguish between different touches on different parts of the surface, allowing students to access and use tools on the screen, move objects and visual aids around on their desktops, and otherwise physically interact with the numbers and information on their screens. By using these screens collaboratively, the researchers say, the students are to some extent teaching themselves as those with a stronger grasp on difficult concepts pull other students forward along with them. What has been found after the new tech is employed
Obtaining Drinking Water from Air Humidity Not a plant to be seen, the desert ground is too dry. But the air contains water, and research scientists have found a 1 of obtaining drinking water from air humidity. The system is based completely on renewable energy and is therefore autonomous. Cracks permeate the dried-out desert ground and the landscape bears testimony to the lack of water. But even here, where there are no lakes, rivers or groundwater, considerable quantities of water are stored in the air. In the Negev desert in Israel, for example, annual average relative air humidity is 64 percent-in every cubic meter of air there are 11.5 milliliters of water. German research scientists have found a way of converting this air humidity autonomously into drinkable water. "The process we have developed is based exclusively on renewable energy sources 2 thermal solar collectors and photovoltaic ceils, 3 makes this method completely energy-autonomous. It will 4 function in regions where there is no electrical infrastructure." says Siegfried Egner, head of the research team. The principle of the 5 is as follows: hygroscopic brine-saline solution which absorbs moistureruns down a tower-shaped unit and absorbs water from the air. It is then sucked 6 a tank a few meters off the ground in which a vacuum prevails. Energy from solar collectors 7 up the brine, which his diluted by the water it has 8 . Because of the vacuum, the boiling point of the liquid is lower than it would be under 9 atmospheric pressure. This effect is known from the mountains: as the atmospheric pressure there is lower than in the valley, water boils at temperatures distinctly below 100℃. The evaporated, non-saline water is condensed and runs down through a completely filled tube in a controlled manner. The gravity of this water column 10 produces the vacuum and so a vacuum pump is not needed. The reconcentrated brine 11 down the tower surface again to absorb moisture from the air. "The concept is suitable for various water 12 . Single-person units and plants supplying water to entire hotels are conceivable, " says Egner. Prototypes have been built for 13 system components-air moisture absorption and vacuum evaporation-and the research scientists have already 14 their interplay on a laboratory scale. In a further 15 the researchers intend to develop a demonstration facility.
Download Knowledge Directly to Your Brain For the first time, researchers have been able to hack into the process of learning in the brain, using induced brain patterns to create a learned behavior. It’s not quite as advanced as an instant kung-fu download, and it’s not as sleek as cognitive inception, but it’s still an important finding that could lead to new teaching and rehabilitation techniques. Future therapies could decode the brain activity patterns of an athlete or a musician, and use them as a benchmark for teaching another person a new activity, according to the researchers. Scientists from Boston University and ATR Computational Neuroscience Laboratories in Kyoto used functional magnetic resonance imaging, or fMRI, to study the learning process. They were examining the adult brain’s aptitude for visual perceptual learning, or VPL, in which repetitive training improves a person’s performance on a particular task. Whether adults can do this as well as young people has been an ongoing debate in neuroscience. Led by BU neuroscientist Takeo Watanabe, researchers used a method called decoded fMRI neurofeedback to stimulate the visual cortex. First they showed participants circles at different orientations. Then they used fMRI to watch the participants’ brain activity. The researchers were then able to train the participants to recreate this visual cortex activity. The volunteers were again placed in MRI machines and asked to visualize shapes of certain colors. The participants were asked to "somehow regulate activity in the posterior part of the brain" to make a solid green disc as large as they could. They were told they would get a paid bonus proportional to the size of this disc, but they weren’t told anything about what the disc meant. The researchers watched the participants’ brain activity and monitored the activation patterns in their visual cortices. "Participants can be trained to control the overall mean activation of an entire brain region, " the study authors write, "or the activation in one region relative to that in another region. " This worked even when test subjects were not aware of what they were learning, the researchers said. "The most surprising thing in this study is that mere inductions of neural activation patterns corresponding to a specific visual feature led to visual performance improvement on the visual feature, without presenting the feature or subjects’ awareness of what was to be learned, " Watanabe said in a statement. Watanabe and colleagues said this method can be a powerful tool. "It can ’incept’ a person to acquire new learning, skills, or memory, or possibly to restore skills or knowledge that has been damaged through accident, disease, or aging, without a person’s awareness of what is learned or memorized, " they Write. What have researchers been able to do with the help of the study
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