It is spoken in detail about
It is reported that
Much/ particular attention is given to
It is shown that
It is stressed that
The article is of great help to
The article is of interest to
The investigation/ research is carried out
The experiment/ analysis is made
The research includes/ covers/ consists of
Special attention is paid/ given to
The following factors are taken into consideration/ account
The paper/ instrument is designed for
A brief account is given of
The author refers to
According to the author
Reference is made to
There are several solutions to the problem
There is some interesting information in the paper about
It is expected/ observed/ proved that
It is reported/ known/ demonstrated that
It appears/ seems that
It is necessary to introduce
It is impossible to account for
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a. Failure to assimilate an adequate quantity of solid food over an extended period of time is absolutely certain to lead, in due course, to a fatal conclusion.
Lack of food causes death.
b. The amphibia, which is the animal class to which our frogs and toads belong, were the first animals to crawl from the sea and inhabit the earth. The first animals to leave the sea and live on dry land were the amphibia.
c. It is undeniable that the large majority of non-native learners of English experience a number of problems in attempting to master the phonetic patterns of the language.
Many learners find English pronunciation difficult.
d. Tea, whether of the China or Indian variety, is well known to be high on the list of those beverages which are most frequently drunk by the inhabitants of the British Isles.
The British drink a large amount of tea.
e. It is not uncommon to encounter sentences which, though they contain a great number of words and are constructed in a highly complex way, none the less turn out on inspection to convey very little meaning of any kind.
Some long and complicated sentences mean very little.
f. One of the most noticeable phenomena in any big city, such as London or Paris, is the steadily increasing number of petrol-driven vehicles, some in private ownership, others belonging to the public transport system, which congest the roads and render rapid movement more difficult year by year.
Big cities have growing traffic problems.
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Laser lidar
Laser-based lidar (light detection and ranging) has also proven to be an important tool for oceanographers. While satellite pictures of the ocean surface provide insight into overall ocean health and hyperspectral imaging provides more insight, lidar is able to penetrate beneath the surface and obtain more specific data, even in murky coastal waters. In addition, lidar is not limited to cloudless skies or daylight hours. One of the difficulties of passive satellite-based systems is that there is water surface reflectance, water-column influence, water chemistry, and also the influence of the bottom, said Chuck Bostater, director of the remote sensing lab at
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Florida Tech University (Melbourne, FL). In shallow waters we want to know the
quality of the water and remotely sense the water column without having the signal contaminated by the water column or the bottom. A typical lidar system comprises a laser transmitter, receiver telescope, photodetectors, and range-resolving detection electronics. In coastal lidar studies, a 532-nm laser is typically used because it is well absorbed by the constituents in the water and so penetrates deeper in turbid or dirty water (400 to 490 nm penetrates deepest in clear ocean water). The laser transmits a short pulse of light in a specific direction. The light interacts with molecules in the air, and the molecules send a small fraction of the light back to the telescope, where it is measured by the photodetectors. The latest version of the Airborne Oceanographic Lidar, the AOL3, weighs only 200 lb and can be carried on a small two-engine plane. Like its predecessors, the AOL3 transmits two laser wavelengths, 355 and 532 nm, which interact with the water molecules, causing a Raman shift that allows normalization of other light measurements to compensate for changes in water clarity. If biological organisms containing chlorophyll and/or phycoerythrin are present in the water, the 532-nm energy is absorbed and re-emitted as particular bands of fluorescence. The 355-nm laser radiation causes fluorescence of some chromophoric dissolved organic material (CDOM)one of the most important inherent optical properties in the ocean because it is one of the few constituents that behaves nearly the same way every day. [Laser Focus World, 2003, v 46, 3, p45]. (356 words)
Summary
The text focuses on the use of laser-based lidar in oceanography. The ability of lidar to penetrate into the murky coastal waters is specially mentioned. Particular attention is given to the advantage of laser-based lidars over passive satellite-based systems in obtaining signals not being contaminated by the water column, according to Chuck Bostater. In addition, a typical lidar system is described with emphasis on the way it works. This information may be of interest to research teams engaged in studying shallow waters. (82 words)
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Volcanic Islands
Islands have always fascinated the human mind. Perhaps it is the instinctive response of man, the land animal, welcoming a brief intrusion of earth in the vast, overwhelming expanse of sea. When sailing in a great ocean basin, a thousand miles from the nearest continent, with miles of water beneath the ship, one may come upon an island which has been formed by a volcanic eruption under the sea. One's imagination can follow its slopes down through darkening waters to its base on the sea floor. One wonders why and how it arose there in the midst of the ocean. The birth of a volcanic island is an event marked by prolonged and violent travail: the forces of the earth striving to create, and all the forces of the sea opposing. At the place where the formation of such an island begins, the sea floor is probably nowhere more than about fifty miles thick. In it are deep cracks and fissures, the results of unequal cooling and shrinkage in past ages. Along such lines of weakness the molten lava from the earth's interior presses up and finally bursts forth into the sea. But a submarine volcano is different from a terrestrial eruption, where the lava, molten rocks, and gases are hurled into the air from an open crater. Here on the bottom of the ocean the volcano has resisting it all the weight of the ocean water above it. Despite the immense pressure of, it may be two or three miles of sea water, the new volcanic cone builds upwards towards the surface, in flow after flow of lava. Once within reach of the waves, its soft ash is violently attacked by the motion of the water which continually washes away its upper surface, so that for a long period the potential island may remain submerged. But eventually, in new eruptions, the cone is pushed up into the air, where the lava hardens and forms a rampart against the attacks of the waves. (333 words)
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Summary
According to the article, a volcanic island is born only after a long and violent struggle between the forces of the earth and the sea. It begins to form when hot lava breaks through a cracked and uneven part of the sea-bed where the earth's crust is weak. Unlike the lava of the land volcano, it has to build upwards despite the immense water-pressure until it finally reaches the surface. At first it is too soft to withstand the waves and remains underwater until the cone is finally pushed into the air by new lava in new eruptions. (98 words)
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http://www.iling-ran.ru/library/sborniki/for_lang/2010_02/15.pdf
