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Методические указания по английскому языку для студентов всех форм обучения Барнаул 2000 (стр. 5 из 6)

5. To attempt to remove heavy scale with the flame is wasteful.

No. 2

1. The pressure in the boiler was too low for the engine to develop such revolutions.

2. In that experiment the steam pipes are known to have been covered to reduce heat losses.

3. Among items to be produced will be cranes , mixers and other equip- ment.

4. We know water to flow through a pipe because of a higher pressure at one end than at the other.

5. To lengthen the life of electrovacuum instruments and to make new highly sensitive and reliable instruments monocrystals are applied.

No. 3

1. Pressure is known to act equally in all direction.

2. The purpose of a compression ring is to prevent gas leakage.

3. To refine the structure of the metal is one of the primary reasons for hot mechanical working of steel.

4. If the alloying element added to a metal is more easily oxidized than the principal metal , the oxide is likely to be predominantly that of the added metal.

5. The components to be treated are loaded onto a mech-belt conveyor.

No. 4

1. A more recent method of protecting the material to be treated is by the use of a vacuum furnace.

2. The fluid is to pumped through the filter chamber into the in tank con-taining clean oil.

3. Many of the compounds to be discussed are unstable under ordinary handling conditions.

4. Carrier gas from tank at first passes to a controller , the usual

purpose of which is to maintain a constant flow of gas.

5. In the inlet to the column there is a simple injector through which

the sample to be analysed will be introduced.

No. 5

1. A further piece of apparatus not always incorporated is a flowmeter to measure the rate of the flow of gas.

2. If the whole of the carbon in the iron is combined, the iron is said to be “ white ” because of the appearance of its fracture.

3. These metals have been found to possess many interesting and useful physical properties.

4. The metal hydroxides react with acids and with oxides of non metals to form water and a class of compounds known as salts.

5. The surface of the metal has to be well cleaned before resins are applied, and at least some hours must be allowed for the resin to cure.

No. 6

1. Electrical conductors are said to be in series if they are connected so that all the current which flows through one conductor must flow through each of the others.

2. In modern tubes, two methods of employing electric current to heat the electron emiter are in use.

3. The dead centre is to be always kept well lubricated with oil.

4. The gas to be examined is enclosed in the graduated tube.

5. Academician N. Semyonov is known to have developed the general physics theory of the chain chemical reactions and to have created the basic of the theory of combustion and explosion.

No. 7

1. Electrical conductors are said to be in series if they are connected so that all the current which flows through one conductor must flow through each of the others.

2. It would be quite wrong to think that conducting materials are the only materials to be used for the transmission of power.

3. To produce a somewhat larger amount of direct current two diode tubes may be combined into one circuit.

4. To accelerate attainment of equilibrium, the air in the vessels can be circulated by a fan.

5. A material with little permanent deformation is said to be brittle.

No. 8

1. An atmosphere of hydrogen is found to give a bright surface without any injurious effect on the material.

2. Engines are also being built to operate on a cycle which is completed in two piston strokes.

3. In most cases, the metal to be forged is heated to its correct forging temperature , but sometimes cold-forging is done.

4. To accelerate the cooling of changes a gas can be admitted to the con- tainers.

5. If the alloying element added to a metal is more easily oxidized than the principal metal , the oxide is likely to be predominantly that of the added metal.

No. 9

1. To accelerate the cooling of changes a gas can be admitted to the containers.

2. The substance discovered has some peculiar properties to be

examined before a final conclusion is made.

3. Manganese in grey iron has been stated to assume two forms manga- nese carbide and manganese sulphide.

4. After heating, the work is passed through a water-jacketed cooling chamber to reduce its temperature.

5. The steels containing 18% tungsten are considered to be the best for most purposes.

No. 10

1. Copper was one of the first metal to be employed for low temperature service.

2. Their slag fibres are believed to give wrought iron an unusually high degree of toughness and of resistance to impact.

2. Tool steels contain enough carbon to cause them to harden.

4. To harden a piece of steel properly it must be in a softened and

annealed state.

5. This heat-treatment process is carried out not so much to produce a soft ductile state, but chiefly to relieve the stresses set up by rolling or other mechanical treatment.

No. 11

1. When any substance or any of its constituent parts combines with oxygen, the substance is said to be oxidized.

2. The killed steel was found to be suitable for many applications such as cold-rolled sheets, galvanized sheets and plates.

3. Water was sprayed into the slag pockets using compressed air for

atomization and proved to be very effective.

4. These machines are extremely rapid in operation and enable important saving in cost to be obtained.

5. To harden a piece of steel properly it must be in a softened and

annealed state.

No. 12

1. The transition temperature of these steel in the hardened condition were found to fall continuously as tempering temperatures were raised.

2. This heat-treatment process is carried out so much to produce a soft ductile state , but chiefly to relieve the stresses set up by rolling or other me-chanical treatment.

3. When any substance or any of its constituent parts combines with oxygen, the substance is said to be oxidized.

4. They found pure silver and the alloys containing tin or copper to be about equal in rate of tarnishing in indoor atmosphere when freshly cleaned.

5. To accelerate the cooling of charges a gas can be admitted to the

containers.

5.4 Chemical technology

No. 1

1. To use oxygen effectively, it was necessary that a simple means be provided for introducing the oxygen into the bath.

2. Plastics considered are to be classified into groups according to their behavior when they are heated.

3. The aim of the experiment to be carried out in our laboratory is to

prove the crystalline structure of the substance under test.

4. The stability of the compound to be formed is to be considered.

5. To decrease the volume of a liquid even very slightly a very high pres- sure must be used.

No. 2

1. According to the kinetic theory a gas is assumed to be made up of par- ticles moving about with random motion.

2. It is necessary to discuss the result , for the experimental data to be dealt with are of great importance in chemistry.

3. Their aim is to find new ways of utilizing this first-class polymer in light industry.

4. The stability of polyethylene plastic in storage is to be associated with the lack of chemically active functional groups in the molecular structure.

5. To regard the polyethylene as a substitute for stainless steel is not proper design procedure.

No. 3

1. For the preparation of an aerosol the substance to be dispersed is first evaporated and the vapour is then quickly cooled.

2. A further piece of apparatus not always incorporated is a flowmeter to measure the rate of the flow of gas.

3. Sample injectors aim to inject a temperature control of the column.

4. The hydrogen atom is believed to have one proton as its nucleus, with one electron circling around it.

5. Carbon is known to occur in two crystalline forms which differ

strikingly in their properties.

No. 4

1. The Raman spectra of ions turns out to be very different from those of the corresponding molecules.

2. In practice, the first step in the study of a reaction is to determine the composition and yield of the products.

3. We should expect sulphur to be less active than oxygen.

4. The substance to be extracted should be more soluble in the extracting solvent than in the initial solution.

5. The particles in the positive rays are assumed to be formed by removal of one or more electrons from the atoms.

No. 5

1. Solutions of hydrogen chloride in all concentrations are shown to be completely ionized in water as a solvent.

2. The purpose of the study of physical chemistry is to understand the laws of chemistry and physics and to predict and control chemical phenomena.

3. The oxygen units with the copper to form copper oxide.

4. The treatment to be given to any sample of water , in order to fit it for industrial use will , of course , depend on the kind of impurities to be removed and should be based upon a careful chemical analyses.

5. Sulphur water is claimed to have medicinal properties and promote good health.

No. 6

1. Solutions of practically all salts, in aqueous solutions of all concent- rations , turn out to be completely ionized.

2. The effect of the solvent is to weaken the union between the proton and the rest of the molecule.

3. The metal hydroxides react with acids and with oxides of nonmetals to form water and a class of compound known as salts.

4. The atoms of radium were shown by experience to be giving off atom of helium.

5. The conditions to be observed are well illustrated in this chapter.

No. 7

1. Oil is thought to have originated from the remains of minute plant and animal organisms.

2. The function of ozone is to oxidize the organic matter, and to sterilize the water.

3. Carbon dioxide reacts with sodium hydroxide to yield water and

sodium carbonate.

4. A gas to be used successfully in such a refrigeration plant must have a high critical temperature.

5. Compounds of phosphorus are likely to be reduced by hot carbon.

No. 8

1. Solutions of carbon dioxide in water are assumed to contain carbonic acid, H2CO3.

2. The purpose of a titration is to measure the concentration of a solution.

3. Liquid oxygen can be kept for some days in a good thermos flask, but slowly evaporates to give gaseous oxygen.

4. Then a small quantity of the liquid to be tested id introduced at the bottom of this tube by means of a medicine dropper.

5. Some of the oxides do not appear to react water at all.

No. 9

1. In the dark hydrogen does not appear to combine with chlorine with appreciable velocity. The reaction seems to require the presence of a

catalyst.

2. A major objective of chemistry is to learn the composition of matter.

3. To maintain electrical neutrality in the oxide, electrones flow across the oxide to the anioun vacancies.

4. An example may best illustrate the helpful information to be gained from such a plot…

5. Chlorine was thought to be a compound of hydrochloric acid and oxy- gen even by Lavoisier.

No. 10

1. The task is to find simple method by means of which one will be able to obtain polymers from cheap raw materials and from the by-products of oil refining, natural gas, coal, etc.

2. Heavy water has been found by numerous tests to contain a very slight amount of hydrogen atom.

3. The stability of polyethylene plastic in storage is to be associated with the lack of chemical active functional group in the molecular structure.

4. The purpose of the detector is to detect the separate components of the mixture as they emerge one by one.

5. Chemical processing method made it possible rationally to utilize

industrial wastes to speed up technological processes and ensure automation.

No. 11

1. The second use of the chromatogram is to enable one to identify the individual components of a mixture qualitatively.

2. For the preparation of an aerosol the substance to be dispersed is first evaporated and the vapour is then quickly cooled.

3. It is desirable to perform a quantitative analysis and a molecular weight determination for an unknown organic compound to be identified.

4. We know gases as nitrogen , helium and argon to make up as much as 26% of pitchblende.

5. Of all the known polymers to be considered in our report we have taken epoxy-resin laminates which may be used at high temperatures.

No. 12

1. Any substance that oxidizes to produce useful heat is a fuel.

2. The manganese dioxide is said to c atalyze the reaction as it does not enter the reaction.

3. To decarburize a bath containing a high initial percentage of chromium a controlled oxidizing period at the highest practical temperature is required if high chromium is to be maintained at low carbon level.

4. To accelerate the cooling of changes a gas can be admitted to the containers.

5. In atmospheres rich in sulphur dioxide, the tin-containing alloy was considered to be more liable to general corrosion than pure silver.

5.5 Mechanical faculty

No. 1

1. The capacity of the new engine is reported to have been increased.

2. To prevent corrosion metal must be covered with paint.

3. To develop high-temperature alloys was of paramount importance.

4. A new method of cutting metals to be developed will solve the problem of machining.

5. The aim of the plant was to develop a new method of cutting metals.

No. 2

1. Tshernov was proud to have found the best temperatures for the hot working of steel.

2. They were to develop a new method of cutting metals.

3. The engineers of that plant are said to have constructed a new device.

4. The only way to produce a pure metal is to eliminate from it all chemical elements but one.

5. To obtain the desired properties of a metal metallurgists alloy it with small amounts of other metals.

No. 3

1. To develop a new method of cutting metals we had to carry out several experiments.

2. The motor is said to have been working for 24 hours without disega-

ging the lathe.

3. If this system is to serve as a voltmeter, a resistor has to be added in series.

4. We know an alternating current to be continuously changing.

5. The metal to be used in our experiment is to be hard.

No. 4

1. The engineer is to design a new high-speed device.

2. These forging machines are known to have performed several operations.

3. This means that a casting to be made in a metal mould must be comparatively short.

4. To understand alternating currents, we must consider two properties of an electric circuit, namely resistance and self-inductance.

5. The new device enables the lathe to be used for a greater range of work.

No. 5

1. Upon examination these bars can be found to contain 0,70 per cent of carbon.

2. We have seen the electric current produce a magnetic field.

3. One of the difficulties to be overcome in obtaining this alloy is to reach the highest possible temperature in the shortest period of time.

4. To increase the productivity of the machine-tool one should know the characteristics of the material which is being machined.

5. To refine the structure of the metal is one of the primary reasons for hot mechanical working of steel.

No. 6

1. To develop a new method of cutting metals was necessary.

2. The spindle is found to be rotating at 3000 r.p.m.

3. The operations necessary to complete a workpiece will determine the number of tools to be used in the turret.

4. Special handling devices allow the vertical rolls of this mill to be changed in a minimum of time.

5. To overcome this trouble various treatments of the molten metal have been suggested and used for degasification.

No. 7

1. In cylindrical grinding the work is known to be held between centers.

2. To serve special uses modern metals and alloys must be more corrosion resistant.

3. The new device enables the machine to be used for a greater range of work.