BORAX
This salt, when crystallised from solution, combines with water forming a hydrate. It is made by adding calcium borate to sodium carbonate solution. It is a white crystalline salt. It is added to the glass, used for enamelling and glazing, to make it more fusible and easier to spread in a thin layer. Since it contains but a small proportion of the metallic oxide, it combines with other metallic oxides if fused with them. For this reason, the powdered salt is sometimes sprinkled on tarnished metallic surfaces being soldered or brazed. The heat of the blowpipe melts the borax and the latter removes the oxide and permits perfect running of the solder over the surface.
The borates thus formed are often coloured and the colours afford a means of recognising the metallic compound which produced them.
In chemical analyses a bead of borax, produced by fusion on a platinum wire, is heated with a particle of the unknown compound and its colour then examined.
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1. In passing through a metal electrons collide with many ions. 2. When the boiling is reached the adding of heat does not raise the temperature. 3. The proper work of an engine depends upon its being well lubricated. 4. All the chemical transformations that take place around us only change energy from one form into another without affecting the total. 5. Coal and any other fuel provide the heat required for driving our engines and turbines. 6. In carrying out the plan of launching an artificial satellite our scientists had to solve many difficult problems. 7. The bridge having been repaired so quickly surprised us very much. 8. Before discussing this question they made a short break. 9. I knew nothing about the recent happenings. 10. Their having crossed the river caused a great surprise. 11. War causes hard sufferings.
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1. A committee has been established for the purpose of coordinating the nomenclature. 2. They continued experimenting with the substance. 3. From here on, the theory starts evaluating the various alternatives of action in terms of the objectives. 4. We have modified the network while retaining the SFS property. 5. Having access to the code was symbolic. 6. It is worthwhile thinking over the effects I have just described. 7. Besides being useful in general interpolation technique, the procedure can be effectively used to approximate the first coefficients of F. 8. The new opportunities may make life on this planet much more worth living. 9. They were against postponing the meeting and for going on with the discussion of this problem. 10. We were all for starting the experiment at once. 11. Operating conditions differed widely. 12. It is customary to dry the precipitate on the paper without removing it from the funnel. 13. They could not help seeing the importance of the process. 14. It is commonly understood that regular queues before a theatre or a cinema are one sign that the show is worth seeing. 15. The purpose of the method is determining system stability. 16. In one's search to understand what happens in this particular case, one cannot help being influenced by the history of quite another problem. 17. We succeeded in building a flexible system 18. Search theory is potentially applicable to any sort of searching process.
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Automation in the Research Process
Our goal should be automating the routine and thereby leave more time for the creative process.
With that word of caution, let's proceed by arbitrarily dividing research into three stages and examining each stage to find what functions of the research process might be automated without endangering creativity. Stage one includes the dreams, the ideas, the exploratory work, selecting the problem, setting the objective, testing technical feasibility, and searching the literature. Stage two involves planning the experiment, conducting the experiment, checking the alternates, data taking, and data evaluation. Stage three is the solution of the problem drawing conclusions and making recommendations.
Although there is a great deal of creativity involved in stage one, there are also opportunities for automation. The burden of keeping up with the literature even in one's own restricted field is becoming heavier with each passing year. The mass of reading necessary to make a literature search has increased immensely. Advances in computer technology have made possible storing and quick retrieving essentially all the scientific literature.
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1. Two special cases are worth highlighting. 2. The question is answered in part by studying the behaviour of the optimal strategy for the task described here. 3. It is worthwhile reconsidering this case as well as adding another even more impressive example. 4. Up to the present time, several writers have succeeded in finding exact solution of the fundamental differential equation in certain particular cases. 5. This justifies our coming here. 6. Programming a computer involves analysing the problem to be solved and a plan to solve it. 7. Having the source code is a way of achieving independence. 8. Today we cannot help witnessing a tendency in science to direct the collective efforts of a research team at the achievement of a common goal. 9. The opening words of this curious treaty are worthy of being recorded. 10. They were accused of being the friends of the Pretender. 11. Peter insisted upon laying aside all the ceremonial of royalty. 12. He had died without leaving either a personal or a political will. 13. Perhaps one of the biggest problems is ventilating suckers. 14. Air cooling instead of water cooling would also reduce the weight of the engine. 15. Trying to minimize the importance of the discovery was of no use. 16. The ability of the device to place max poles while preserving others is clearly attractive. 17. Life is a matter of making wise choices - of knowing when to draw the line. 18. The method as developed by W. R. Evens is indicating the location of roots of the characteristic equation.
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ELASTICITY
Pulling a rubber band increases its length. However, if you cease pulling it and release one of its ends, the rubber band will quickly return to its original shape and size.
Solids in greatly differing degrees resist being changed in shape, i.e. resist deformation. Some of them, like a rubber band or a steel spring, are called elastic because they return to their original size and shape after having been stretched or compressed. Others are known as elastic because they straighten after having been bent.
Gases and liquids are perfectly elastic. In spite of then having been compressed they return to their original volume after the removing of the applied force.
Air, for instance, is perfectly elastic. If it is compressed and then allowed to return to its original pressure and temperature, it returns exactly to its original volume.
We may define an elastic body as one tending to return to its original shape and size when the deforming force is removed. On the contrary, bodies that are not very elastic do not show the tendency of returning to their original form. Thus, elasticity is the tendency to return to the original condition after deformation.
Careful experiments made on various elastic materials show that there is a simple relationship existing between the acting force and the resistance force. This relationship must have a limit somewhere and the stretching cannot be increased indefinitely.
Elastic limit is the point beyond which one should not attempt deforming the body if it is to return to its original condition.
As we are stretching an elastic object such as a steel spring, for instance, there must come a time when the elastic limit is reached, and then the above-mentioned relationship will not hold any longer. However, stretching the steel spring repeatedly or leaving it stretched moderately has no practical effect upon it. Considering further the example of the rubber band, one finds that the more the rubber band is pulled, the longer it will become until the elastic limit is reached, at last. It is known, however, that rubber can stretch a relatively long distance before reaching the elastic limit.
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1. assign a numerical value to the inertia of any given body, we choose as a standard somebody whose inertia is arbitrary taken as unity. 2. Each organ of the living organism has its own work to do. 3. When cells which have similar functions become congregated together to form distinct anatomical structures, we call such structures organs. 4. Oxygen is extremely hard to liberate from a compound. 5. The disintegration of radioactive substances is known to be a spontaneous process. 6. We know the electric cell to consist of two plates of conducting material assembled together and immersed in an electrolyte. 7. Atomic energy is likely to become the main source of power-supply in the years to come. 8. Dilute solutions appear to obey laws exactly analogous to the laws of gases. 9. The difficulties to overcome in the manufacture of synthetic camphor seem to be great. 10. There was a time when lightning proved to be a dangerous problem to be solved. 11. Devices for changing ac into dc are needed to charge storage batteries. 12. The weather is unlikely to change for the better in the coming days. 13. I asked him to inform me about the results of the test.
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A. 1. To make a choice between these two alternatives is not an easy task. 2. To be on the safe side, take special care of the accuracy of the calculation. 3. To foresee what the future will be like requires analysis of the past experience. 4. To tell the truth, the results have no direct bearing on the problem under investigation. 5. To argue about it is not fruitful at the moment. 6. To establish cause-effect relationship between smoking and some diseases, extensive research is being carried on at several research centres. 7. To sum up, synthetic problems are studied for the possibilities which they hold for practical applications. 8. To put it another way, the experimental procedure must suit the purpose of the experiment. 9. To be able to forecast the future, we must begin by a thorough analysis of the past course of events.
. 1. The aim was to discuss the impact of scientific activity on technology. 2. If we are to achieve the aim we must confine our attention to one point only. 3. Perhaps the greatest problem at present is to get some understanding of the remarkable phenomenon of memory. 4. The original idea was to take advantage of the high temperature of the process. 5. Glass which is to be used for lenses must be almost colourless. 6. The train is to reach its destination in 52 hours. 7. The joint programme of Russian and foreign scientists on space research is to be discussed at the next COSPAR conference. 8. Many terrigenous bacteria which have become adapted to salt water are to be found close inshore.
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The design of an automatic computer is not a simple matter. To understand how to use a computer one must fully appreciate its design. Therefore, a brief introduction to the logical design is necessary for the users to understand the underlying idea. To present some background material on theoretical and philosophical aspects of information processing is to give the user more profound understanding of computers' application. From what has been said above, it is clear that a computer may be thought of both as a machine by which to handle information and a machine by which to transform one set of symbols into another. For the user it is a machine to process the information, a way to obtain an output by applying to an input a specified sequence of logical operations. The designer considers a computer to be a device for applying a sequence of logic operations to symbols representing information.
Since mathematical operations are a particular group of logic operations, the consideration of logic operations by definition includes mathematical operations. To appreciate the significance of the conventional character of logic, and to gain some understanding of computer logical design we must consider a few simple games. These games are to illustrate some significant factors.
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1. There is one more important factor to be considered. 2. it is of importance to know the basis principle to be observed in the design and use of optical equipment. 3. To summarize the findings of the tremendous work would require many pages. 4. It is ironical that we publish articles on cybernetics yet fail to develop simple and effective feedback mechanisms to serve our purpose. 5. To specify the model in this field will require advances both in mathematics and physics. 6. Such a chapter would necessarily have too ephemeral value to be worth undertaking. 7. To construct an experiment of this kind seems nearly impossible. 8. It is this type of change which is particularly to be avoided. 9. Under these circumstances the computer cannot be made to function. 10. To be sure, much of this work was initiated from actual applications. 11. The theory to be developed only aims at verifying to above discussions but is not sufficiently detailed to give a complete description. 12. The habitations of the common people were rude huts made so as to be easily taken down.
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GRAVITY
The force of gravity is known to play an important part in many common phenomena of mechanics, as well as in everyday life.
We know the weight of a body to be nothing but the pull of gravity toward the earth. A body is said to weigh one kilogram if the mass of the earth exerts upon it a pull equal to one kilogram.
According to the universal Law of Gravitation, any two objects in the Universe are attracted to each other with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
The Law of Gravitation is universal, of course, but it is impossible to notice the force between two ordinary objects, as the attraction between them is too small to be perceptible at all.
But with a body as large as the Earth or the Moon it becomes a different thing. It is this force that holds the planets in their circular orbits and due to this very force the first man-made earth satellite created by Soviet scientists began to circle around our Globe.
We know gravity to pull on every particle of a body so that its weight is actually distributed throughout the body. But a solid body seems to have one point at which it can be supported by a single upward force; this point is called the centre of gravity. In technique the centre of gravity is considered to be the location of the resultant of all gravitational pulls exerted on the body.
Now we are to consider the question of stability, interrelated with gravity.
A book lying on a table is expected to keep its position without any difficulty, as one knows it to be in a state of equilibrium. However, to make it stand on end is not so' easy at all. In the same way, a pencil will lie on the table without any tendency to tip over. With some difficulty one can even make it stand on its unsharpened end, but it will not stand at all upon its sharp end.
All common objects differ in their tendency to keep a given position, their stability depending on their shape, weight, and position, and everyday experience shows us that heavy objects are harder to tip over than light ones.
The stability of an object is measured by the amount of work to be required to make it take a new position. The lower the centre of gravity, the greater the stability of an object; that is why, to increase the stability of a motorcar, its designer tries to keep the centre of gravity as low as possible.
