the age of the

The two rocks were of an age (or of the same age).

The distribution of the molecules throughout the available energy levels...

The radial distribution of bound-ray power over the core cross section.:.

The distribution of coal by rank, geologic age, and district...

The superiority of Democritus' model was not recognized until the dawning of the age of science.

The Mississippian system takes its name from the river along which strata of this age are exposed.

The Mississippian system takes its name from the river along which strata of this age are exposed.

The actual age of the rock may be approximated by measuring...

The ( surface) exposure of strata of Palaeozoic age...

Outcrops (or Outcroppings) of bituminous sand...

The ( surface) exposure of strata of Palaeozoic age...

Outcrops (or Outcroppings) of bituminous sand...

The percent( age) composition of alloys and rocks may be derived from such observations.

With this microscope the particles can be magnified up to 15,000 times.

The age of very ancient rocks may be measured using the potassium-argon method.

By (or With) such a method...

The dry box is evacuated by a vacuum pump.

The bearings are mounted on the shaft by the use of a hydraulic system.

Refuelling is accomplished with [ the aid (or help) of] (or by means of) a simple machine.

Solid state bonds can be achieved with ( the use of) ultrasonic welding.

The surface of normal velocity may often be constructed by means of the reciprocal surface.

Circular polarization is obtained through the use of the slots...

Irregular surfaces can be treated by use of the servo control system.

We can introduce the curves through Eq. (.14).

The stereochemical relationships between... can be determined by reference to the Fischer projection of...

The gas laws can be understood through a model.

The distribution of craters agrees broadly with estimates of...

The world's chemical industry then marketed an estimated 1000 new synthetic chemicals each year.

The conglomerate was tilted to something like 45 degrees.

In a million years or so even the most rapidly spinning neutron star slows down.

This concept appeared near the middle of the 19th century.

Theoretically iron crystals should resist deformation at stresses approaching [or of about (or around), or in the neighbourhood of] several million psi.

The machine age in the glass container industry started around 1890.

These steels have yield strengths in the 2,000,000 psi area (or in the area of 2,000,000 psi).

The maximum strain was in the neighbourhood (or vicinity) of 2%.

The thermal efficiency of these units will be in the region of (or approximately) 40%.

These disturbances are propagated at roughly the speed of sound.

The "dilute form" in percent of total concentration was calculated roughly.

Some 250 Mcf of nitrogen was pumped into the line.

An expression for the sound speed in a gas may be obtained very crudely as follows.

The terminal velocity is roughly constant.

The focal length is 50 mm or thereabouts.

The laser output pulses have an estimated power of over 1 MW.

The strip should be heated at around 1200°F.

In the U.S. the average (or median) age of the population declined between censuses.

The average gas-oil ratio is 1400 cu ft per barrel.

is the mean molecular weight of the product gases.

A median lethal dose of radiation...

At low Reynolds number the value of is small, it increases toward unity at medium Reynolds number.

In the medium exposure ranges maximum development occurs.

Small and medium-size() castings.

The process has proved successful for the production of grains of moderate size but is not suitable for very large grains.

Cadmium is the middle member of group IIb in the Periodic Table.

At intermediate and slow rates of exchange...

Let us imagine that each molecule of a magnetic substance is a tiny magnet in itself.

These two features alone do not provide an adequate description of...

The average result has little value by itself.

Catalysis is so important that the chemist considers it a subject by itself.

The rays are not in themselves colour making.

Each of the density ranges is quite broad in itself.

Isotope sources are not competitors of machines per se.

The large clouds and large globules will probably collapse on their own under the force of their own gravitation.

Each processing element of the computer is a powerful computing unit in its own right.

Chronological age on its own is not a contra-indication to surgical intervention.

The silicate framework is electrically neutral and can exist by itself.

The molten material did not burst out on (or of) its own accord.

This explanation is correct as far as it goes, but it is hardly satisfying.

None of these phenomena would seem by itself to be a convincing cause of the reptilian extinctions.

Taken alone, this shift is insufficient for describing...

Several methods were used to arrive at an estimate of earth age.

Van der Waals' equation is arrived at (or deduced, or derived) by assuming that...

Additional resolution can be gained by using...

You can substitute... and come up with a true equality.

This value is found (or obtained) from the eigenvalue equation.

To secure information on...

Related equations can be worked out in the same way.

From (A3) we have (or get, or obtain):...

The natural dyestuffs are derived from plants or animals.

By drilling hundreds of holes they recovered 50,000 core samples.

They were able to secure about a 20% yield of...

Bromate may be formed from bromide electrolytically.

The operating pulses could be derived (or obtained) from a contact breaker.

A more uniform production of acetylene gas that can be had from the untreated calcium carbide...

In that period, many antibiotics were isolated in pure form.

Ammonium chloride is made (or prepared, or produced, or obtained) by absorbing ammonia in hydrochloric acid.

The weight of... is derived from the ratio of...

To put in the forefront.

This discovery brought to the fore the age-old question of...

Preference is given to the largest group.

The proximate analysis is preferred.

In this age of computers the attraction is toward a two-based system.

Mechanical seals are increasingly favoured by industry.

The approach favoured by our group is a much more empirical one.

To decide between two theories,...

The spark was preferred to the arc.

Polarization helps us to understand why some molecules are favoured over their ionic counterparts.

It is unlikely that anyone would be irradiated by a single beam for any length of time.

A child who has suffered undernourishment very early and for an appreciable length of time will never reach normal size for his age.

The text was developed over a protracted period of the last 10 years.

The screens are designed to give maximum output over prolonged (or extended) periods.

It is unlikely that anyone would be irradiated by a single beam for any length of time.

A child who has suffered undernourishment very early and for an appreciable length of time will never reach normal size for his age.

The text was developed over a protracted period of the last 10 years.

The screens are designed to give maximum output over prolonged (or extended) periods.

With the invention of the vacuum triode the age of electronics was ushered in.