"D" could have been a door symbol, like inAncient EgyptOfHieroglyphicsLi (1).When did it first appear in the written form of the Semites? We have no idea.Around 1000 BCBebruce(Ancientmediterranean seaHong Kong City, located in current LebanonBeirutNortherlyJubail, became prosperous in the second millenniumPhoeniciaCity) and some other places of Phoenicia, as well as the center of Canaan, this symbol is a specific linear form (2), for the sexual form of.It is called th in Semitic language, meaning door.
The Greek changed the name of the Semitic people to delta, and they retained the Phoenician symbols (3).In the Italian colony of Khalkis (or Chalcis Karkis) in Greece, there was a slight radian (4).This shape makes it also exist inLatinIn writing (5).From the Latin era, the triangle gradually became smooth (6).
(2) For the form of sex.In the Semitic family (i.eSemitic）Its language is th, meaning door.The Greek changed the name of the Semitic people to delta, and they kept itPhoeniciaHuman symbol.
(3) OnItalyThe letters of Khalkis (or Chalcis Kalkis), a Greek colony, have a slight radian.
(4) This shape makes it also exist in Latin writing.
(5) From the Latin era, the triangle has gradually become smooth.
Sumerian D â let may be from rainOR GateThumbnails developed from.In the Semitic language,ancient Greek(ModernGreek/δ/) andLatinThe letter in the middle sounds/d/.In Etruscan.This letter is redundant.But it remains (see letter B).
In atlas 03G101, there is also the binding of tensile reinforcementLap lengthCalculation=correction factor× Anchor length correction coefficient is based on longitudinal reinforcementLap jointthe measure of areapercentage Determination: 1. Take 1.25 2, 50% 1.4 3, 100% 1.6 when ≤ 25%.
In any case, the overlapping length shall not be less than 300mm;The lap length of compression reinforcement is calculated as 0.7 times the lap length of tension reinforcement
Textile industry
In the textile industry, capital D is generally used to indicate the yarn thickness.
The calculation formula is: Td=9000 × GK/L;Where: Td -- fiberDenier number(Dan);L -- fiber length (m);GK -- mass of fiber at the specified moisture regain (g).
It is a non legal unit in China, but it is often used in foreign tradechemical fiberAnd silk field.
Medical Science
The length of the longest part between the left and right sides of the head is also called the "big transverse diameter of the head".When the first trimester of pregnancy cannot passCRLTo determine the expected production dateB-mode ultrasonographyMeasure D to predict;After the metaphase, when estimating the fetal weight, it is often necessary to measure the data.
