Permeable sentence example
The crust of the earth, so far as it is permeable and above the sea-level, receives from rainfall its supply of fresh water.
The conception of a semi-permeable membrane, permeable to the solvent only, was used by van't Hoff as a means of applying the principles of thermodynamics to the theory of solution.
On the upheaval of such rocks above the sea-level, fresh water from rainfall began to flow over their exposed surfaces, and, so far as the strata were permeable, to lie in their interstices upon the salt water.
Known as confined aquifers, they are pools of fresh water trapped in permeable rock strata at depths of 300 to 6,000 feet.
This is reflected in unprecedented June runoff totals for some southern rivers draining permeable catchments.Advertisement
The river Itchen is an example of a permeable chalk catchment.
Within the context of lowland permeable catchments, a single site would not be sufficient to address all issues satisfactorily.
Soft and Gas permeable contact lenses start at £ 49 per pair, with daily disposables at £ 1 per pair.
Soft and Gas Permeable contact lenses start at £ 49 per pair, with daily disposables at £ 1 per pair.
Design examples Park and ride schemes -- uses permeable pavements, swales, filter strips and ponds to treat diffuse pollution.Advertisement
Moisture properites Sto renders offer protection from driving rain, yet remain vapor permeable.
Applied research From the outset we have sought to protect our basic research activity with a " permeable membrane " of applied research.
Main SUDS used permeable paving has been used in the Phase 3 parking areas with a total site area of approximately 1.2 Ha.
We have asked Berkeleys to redesign this junction - to conform to their stated policy of making the whole site permeable on foot.
Reverse osmosis a high pressure filtration system that uses selectively permeable membranes with extremely small pores to separate ions and particles.Advertisement
Perhaps some of the barriers may now become more permeable.
If this is the case then it may well be that an attitudinal border may prove much less permeable than an economic one.
The buildings on the north side of Eastgate are good enough to retain, tho they could be made more permeable at ground level.
Mirror tinted contacts are only available in gas permeable lenses.
Rigid gas permeable (RGPs) contact lenses are used to correct myopia.Advertisement
The soil needs to be permeable with proper drainage.
An increase in non permeable hard surface areas can significantly reduce levels of groundwater recharge.
The use of vapor permeable underlay to improve the thermal performance of the roof will inevitably change the roof ventilation requirements.
Cushny has shown experimentally that slowing of the blood-flow through renal tissue causes less sodium chloride to appear in the urine while the excretion of urea and sulphates remains unaffected; apparently the chloride, being more permeable, is reabsorbed and so only appears to be excreted in less quantity.
Reverse Osmosis works using water pressure, water is forced through a semi permeable fabric, also known as the membrane.Advertisement
Lay down permeable landscaping fabric, cutting holes for the stones, and stake it to the ground.
They come in various styles from daily disposables to gas permeable.
Mirrored contact lenses come in gas permeable only and only one size.
It is important to be fitted by an eye care professional when planning on wearing this type of lenses so they can assess if your eyes are in the condition needed to wear a gas permeable lens.
Additionally, Acuvue lenses are made of an extremely high oxygen permeable material, which is better for your eyes.
The famous Venetian pozzi, or wells for storing rain-water from the roofs and streets, consisted of a closed basin with a water-tight stratum of clay at the bottom, upon which a slab of stone was laid; a brick shaft of radiating bricks laid in a permeable jointing material of clay and sand was then built.
As sodium chloride is one of the most permeable of crystalloids it seems strange that damage to the renal tissue should impede its excretion.
Let us suppose that we possess a partition such as that described above, which is permeable to the solvent but not to the solute when dissolved in it, and let us connect the solution and solvent of fig.
The positions of springs are determined by permeable depressions in the surface of the ground below the general level of saturation, and frequently also by the holding up of that level locally by comparatively impermeable strata, sometimes combined with a fault or a synclinal fold of the strata, forming the more permeable portion into an underground basin or channel lying within comparatively impermeable boundaries.
At the lower lips or at the most permeable parts of these basins or channels such rainfall as does not flow over the surface, or is not evaporated or absorbed by vegetation, and does not, while still below ground reach the level of the sea, issues as springs, and is the cause of the continued flow of rivers and streams during prolonged droughts.
The Upper and Middle Chalk are permeable almost through their mass.
With the exception of the Red Marls forming the upper part of the Keuper, most of the New Red Sandstone is permeable, and some parts contain, when saturated, even more water than solid chalk; but, just as in the case of the chalk, a well or borehole in the sandstone yields very little water unless it strikes a fissure; hence, in New Red Sandstone, also, it is a common thing to form underground chambers or adits in search of additional fissures, and sometimes to sink many vertical boreholes with the same object in view.
The formation is probably more or less permeable throughout; it consists largely of loose sand and takes the general south-easterly dip of British strata.
Precisely the same thing happens in the actual crust of the earth, except that, in the formations usually met with, the strata are so irregularly permeable that no such uniform percolation occurs, and most of the water, instead of oozing out near the sea-level, meets with obstructions which cause it to issue, sometimes below the sea-level and sometimes above it, in the form of concentrated springs.
Thus natural or artificial surfaces which are completely permeable to rainfall may become almost impermeable when protected by surface water from drought and frost, and from earth-worms, vegetation and artificial disturbance.
Slowly permeable seasonally waterlogged clay soils over Tertiary clay (Windsor series ).
A partially permeable membrane is just one with small holes in it.
In areas where the soil or fill beneath the building is highly permeable blowing can work better than sucking.
These features occur on what is a very permeable rock which does not generally support surface drainage systems.
Because the mortar is not permeable this moisture cannot evaporate from the mortar joint once rain stops.
Rigid gas permeable lenses are even more likely to dry out and cause dry eyes.
If you're a rigid gas permeable lens wearer, you're not home-free just because your lenses don't contain water, unfortunately.
Some are designed for soft lenses; others are designed for rigid gas permeable lenses.
Hard contact lenses are made of a rigid plastic and are also called rigid gas permeable lenses.
Do you want to know the difference between gas permeable contacts versus soft contact lenses?
If you lose your gas permeable lens then it will need to be replaced with a whole new lens.
Gas permeable lenses are rigid and hold their shape when blinking, resulting in crisp vision.
Water is not contained in gas permeable lenses so lipids and proteins found in tears do not stick to them as they do to soft lenses.
Both soft and gas permeable contact lenses have advantages and disadvantages.
Hard contact lenses, also known as rigid gas permeable hard contact lenses, are sometimes prescribed because they can provide a clearer view for some prescription types.
A hybrid contact lens combines the perks of rigid gas permeable lenses with those of soft contacts to give you the clear vision of rigid gas permeable lenes and the comfort of soft contacts.
Both soft contact lenses and rigid gas permeable lenses have their advantages and disadvantages.
Advantages of rigid gas permeable lenses include the ability to allow more oxygen to the eye, clearer vision because they maintain their shape regardless of tear content and other factors that can affect the wear of a soft lens.
Rigid gas permeable lenses are not, however, known for their comfort.
There is usually at least an adjustment period when switching from glasses or soft lenses to rigid gas permeable lenses, though some users never feel comfortable wearing them.
In many cases, they are not meant to be worn for as many consecutive hours as rigid gas permeable lenses because they don't always allow proper oxygen flow to the eye.
The hybrid contact lens has the rigid gas permeable center with a soft lens "skirt" extending out past the iris to offer a more comfortable fit.
You get the feel of the soft contact's outer edges with the sharp vision of the rigid gas permeable lens centered over the pupil of the eye.
To care for your hybrid lenses, treat them as you would treat rigid gas permeable or soft lenses.
If you're suffering from discomfort from your rigid gas permeable lenses or less than clear vision from your soft lenses, trying a pair of hybrid contacts may be worth a try.
The wear and care of them are not much different than other types, but they combine the best of the rigid gas permeable and soft lenses.
Still others, such as rigid gas permeable lenses, can be worn for a year.
Also, please keep in mind that rigid gas permeable lenses are usually not available in theatrical styles; almost all of the novelty or theatrical contacts available are soft lenses.
Rigid gas-permeable (RGP) extended-wear lenses are made from plastic that also does not absorb water but is more permeable to oxygen than the plastic used for daily-wear lenses.
Daily wear soft lenses are made of plastic that is permeable to oxygen and absorbs water; therefore, they are soft and flexible.
Extended-wear soft lenses are highly permeable to oxygen, are flexible by virtue of their ability to absorb water, and can usually be worn for up to one week.
Studies have linked the condition of permeable intestinal tracts or leaky gut with autism.
In the New Red Sandstone, the Greensand and the upper Chalk, we find the opposite extremes; while the igneous rocks are for the most part only permeable in virtue of the open fissures they contain.
Although such uniformly permeable sand is rarely met with in great masses, it is useful to consider in greater detail so simple a case.
Dams Any well-made earthen embankment of moderate height, and of such thickness and uniformity of construction as to ensure freedom from excessive percolation at any point, will in the course of time become almost impermeable to surface water standing against it; and when permeable rocks are covered with many feet of soil, the leakage through such soil from standing water newly placed above it generally diminishes rapidly, and in process of time often ceases entirely.
Thus the permeable vein grows vertically rather than horizontally, and ultimately assumes the form of a thin vertical sheet traversing the puddle wall, often diagonally in plan, and having a thickness which has varied in different cases from a few inches to a couple of feet or more, of almost clean sand rising to an observed height of 30 or 40 ft., and only arrested in its upward growth by the necessary lowering of the reservoir water to avoid serious danger.
For similar reasons care must be taken to ensure that the structure of the water face of the dam shall be the least permeable of any part.
If the pores of the water face are thus rendered extremely fine, the surface water, carrying more or less fine detritus and organic matter, will soon close them entirely and assist in making that face the least permeable portion of the structure.
Most of the streams maintain a good flow of water in the driest seasons, and in case of heavy rains many of them " underflow " the adjacent bottom lands, saturating the permeable substratum of the country with the surplus water, which in time drains out and feeds the subsiding streams. This feature is particularly true of the Saline, Solomon and Smoky Hill rivers.
The other type of contact lens is the gas permeable.
It is also known as rigid gas permeable contact lens.
For many eye conditions, gas permeable lenses offer clearer vision.
How do you decide if you want to wear gas permeable contacts versus soft contact lenses?
Soft contacts can be more comfortable when first inserted into your eyes than the gas permeable lenses.
If you do not wear gas permeable lenses for a week, there will be a certain amount of time that it takes to get used to them.
The condition, therefore, that there shall be no tension is important as an element of design; but when we come to construction, we must be careful also that no part of the wall shall be less permeable than the water face.
On permeable soils, especially those of the terrace lands along the valleys, the soluble salts commonly known as alkali were gradually leached out and carried by the percolating waters towards the lower lands, where, reaching the surface, the alkali was left as a glistening crust or as pools of inky blackness.
But it is never advisable to rely upon this action, where, as in the case of a reservoir for water supply, large portions of naturally permeable bottom are liable to be uncovered and exposed to the weather.
They may be quite permeable, but to prevent undue settlement and distortion they must, like the puddle, be well consolidated.
In order to prevent a tendency to slip, due to sudden and partial changes of satura tion, the outer embankment should always be permeable, and well drained at the base except close to the puddle.
The less permeable materials should be confined to the inner parts of the embankments; this is especially important in the case of the inner embankment in order that, when the water level falls, they may remain moist without becoming liable to slip. The inner slope should be protected from the action of waves by so-called " hand-pitching," consisting of roughlysquared stonework, bedded upon a layer of broken stone to prevent local disturbance of the embankment by action of the water between the joints of the larger stones.
The actual coal measure strata, consisting mainly of shales and clays, are generally impervious to water, but when strata of a permeable character are sunk through, such as the magnesian limestone of the north of England, the Permian sandstones of the central counties, or the chalk and greensand in the north of France and Westphalia, special methods are required in order to pass the water-bearing beds, and to protect the shaft and workings from the influx of water subsequently.
As the drainage by cuniculi removed the moisture in the subsoil, so the drainage of the lakes by emissaria, outlet channels at a low level, prevented the permeable strata below the tufa from becoming impregnated with moisture which they would otherwise have derived from the lakes of the Alban Hills.