ผลการค้นหา

Autotrophic

แปลว่า(Environmental Engineering) Organisms which utilize inorganic carbon for synthesis of protoplasm. Ecologists narrow the definition further by requiring that autotrophs obtain their energy from the sun. In microbiologist parlance, this would be a photoautotroph. See photoautotrophic and chemoautotrophic.

Peeling

แปลว่า(Concrete Engineering) A process in which thin flakes of matrix or mortar are broken away from concrete surface; caused by adherence of surface mortar-to forms as forms are removed, or to trowel or float in portland cement plaster.

Saponification

แปลว่า(Concrete Engineering) The deposit of a gray scum or gray dust on the inside surface of a subgrade wall or floor; as the result of moisture moving through the concrete and washing certain chemicals from the concrete mass.

Colloids

แปลว่า(Environmental Engineering) Small particles which have a negligible settling velocity. These particles have a very small mass so gravitational force is low compared to surface frictional forces. Typical colloidal sizes range from 10-3 mm to 1 mm.

Brinell Hardness

แปลว่า(english) The hardness of a metal or part, as represented by the number obtained from the ratio between the load applied on the spherical area of the impression made by a steel ball forced into the surface of the material tested.

Backoff

แปลว่าRemoval of part of coil from entry end of unit; may be necessitated by a defect in coil or by a wreck in the mill, etc. Backoff weight is the part of the coil that is removed and not finished/produced.

Cell

แปลว่า(Environmental Engineering) A unit of varying dimensions in a landfill which is isolated from the environment by 6 to 12 inches of soil cover. A cell is one day's waste or less. A cell is covered with soil at the end of each day.

Basic Oxygen Furnace (BOF)

แปลว่า(english) "WHAT A pear-shaped furnace, lined with refractory bricks, that refines molten iron from the blast furnace and scrap into steel. Up to 30% of the charge into the BOF can be scrap, with hot metal accounting for the rest. WHY BOFs, which can refine a heat (batch) of steel in less than 45 minutes, replaced open-hearth furnaces in the 1950s; the latter required five to six hours to process the metal. The BOF's rapid operation, lower cost and ease of control give it a distinct advantage over previous methods. HOW Scrap is dumped into the furnace vessel, followed by the hot metal from the blast furnace. A lance is lowered from above, through which blows a high-pressure stream of oxygen to cause chemical reactions that separate impurities as fumes or slag. Once refined, the liquid steel and slag are poured into separate containers. "

Billet

แปลว่า(english) (1) A semi-finished section hot rolled from a metal ingot, with a rectangular cross section usually ranging from 16 to 36 in., the width being less than twice the thickness. Where the cross section exceeds 36 in., the term “bloom” is properly but not universally used. Sizes smaller than 16 in. are usually termed “bars”; a solid semi-finished round or square product which has been hot worked by forging, rolling, or extrusion. (2) A semi-finished, cogged, hot rolled or continuous-cast metal product of uniform section, usually rectangular with radiused corners. Billets are relatively larger than bars.

Centroid:

แปลว่า(english) Similar to the concept of center of gravity, except that it applies to a two dimensional shape rather than an object. For a given shape, the centroid location corresponds to the center of gravity for a thin flat plate of that shape, made from a homogeneous material.

Nitrification

แปลว่า(Environmental Engineering) The biological oxidation of ammonia and ammonium sequentially to nitrite and then nitrate. It occurs naturally in surface waters, and can be engineered in wastewater treatment systems. The purpose of nitrification in wastewater treatment systems is a reduction in the oxygen demand resulting from the ammonia.

Section Modulus:

แปลว่า(english) A property of a cross sectional shape, which depends on shape, and orientation. Section modulus is usually denoted S, and S = I/c, where I = moment of inertia about an axis through the centroid, and c is the distance from the centroid to the extreme edge of the section.