ammonia

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ammonia

 [ah-mo´nyah]
a colorless alkaline gas, NH3, with a pungent odor and acrid taste, and soluble in water.
ammonia N 13 ammonia in which a portion of the molecules are labeled with 13N; used in positron emission tomography of the cardiovascular system, brain, and liver.

am·mo·ni·a

(ă-mō'nē-ă),
A colorless volatile gas, NH3, highly soluble in water, capable of forming a weak base, which combines with acids to form ammonium compounds.
[fr. L. sal ammoniacus, salt of Amen (G. Ammōn), obtained near a temple of Amen in Libya]

ammonia

Biochemistry
An irritating, water-soluble, strongly basic, colourless gas, which is lighter than air.
 
Industry
Ammonia (NH3) is used in explosives, fertilisers, refrigerants and household cleaning solutions.
 
Physiology
NH3 is produced in the liver, intestine and kidneys as an end-product of protein metabolism; the liver converts ammonia into urea, which is then excreted by the kidneys; in liver disease this conversion is decreased, resulting in increased serum ammonia. Serial measurement of ammonia is used to follow progression of hepatic encephalopathy in Reye syndrome and other conditions.
 
Ref range
15–49 µg/dL.
 
Abnormal values
Increased hepatic coma, Reye syndrome, severe CHF, GI haemorrhage, erythroblastosis fetalis, drugs (e.g., diuretics and antibiotics).

ammonia

NH3 Physiology NH3 is produced in the liver, intestine, and kidneys as endproduct of protein metabolism; the liver converts ammonia into urea, which is then excreted by the kidneys; in liver disease this conversion is diminished, resulting in ↑ serum ammonia; serial measurement of ammonia is used to follow the progression of hepatic encephalopathy in Reye syndrome and other conditions Ref range 15-49 µg/dL Abnormal values ↑ Hepatic coma, Reye syndrome, severe CHF, GI hemorrhage, erythroblastosis fetalis, drugs–eg, diuretics and antibiotics. See Hepatic encephalopathy.

am·mo·nia

(NH3) (ă-mō'nē-ă)
A colorless volatile gas, NH3, highly soluble in water, capable of forming a weak base, which combines with acids to form ammonium compounds.
[fr. L. sal ammoniacus, salt of Amen (G. Ammōn), obtained near a temple of Amen in Libya]

ammonia

A substance produced when AMINO ACIDS are broken down. Ammonia is converted by the liver into urea and excreted in the urine. Urea can be broken down by bacterial enzymes to release ammonia. This may be a cause of nappy rash in babies.

ammonia

a colourless gas, which is the main form in which nitrogen is utilized in living cells. Formula: NH3.

am·mo·nia

(ă-mō'nē-ă)
A colorless volatile gas, NH3, highly soluble in water, capable of forming a weak base, which combines with acids to form ammonium compounds.
[fr. L. sal ammoniacus, salt of Amen (G. Ammōn), obtained near a temple of Amen in Libya]
References in periodicals archive ?
The high-efficiency refrigeration systems utilizing low GWP refrigerants, including R-1234yf, R-717, and R-744, can drastically reduce carbon dioxide emissions as compared to the baseline R-404A multiplex DX refrigeration system.
For R-50 and R-717, which are lighter than oxygen, the effects of the preferential diffusion are reversed.
Ozone Global Ct Boiling Depletion Warming ([degrees] Temperature Potential Potential C) ([degrees]C) R-22 0.055 1,700 96 -41 R-23 0 12,000 26 -82 R-134a 0 1,300 101 -26 R-404A 0 3,780 73 -47 R-410A 0 1,980 72 -51 R-717 0 0 133 -33
Additional Nondimensional Cycle Simulation Results for the Fifteen Most Promising Pure Fluids as Potential R-114 Replacements Refrigerant [P.sub.evap] [P.sub.cond] [P.sub.comp,ratio] Ratio Ratio Ratio R-245eb 0.502 0.582 1.158 R-245ca 0.475 0.623 1.311 R-245fa 0.697 0.859 1.233 [SF.sub.5][CF.sub.2]H 0.938 0.960 1.024 R-E236fa 0.953 1.030 1.081 R-E245cb1 0.953 1.036 1.087 R-236ca 0.981 1.075 1.010 R-236ea 0.964 1.085 1.124 R-143 0.957 1.025 1.071 R-236cb 1.198 1.229 1.026 R-254cb 1.148 1.148 1.000 R-13I1 2.254 1.914 0.849 R-764 1.834 1.940 1.058 R-152a 2.770 2.502 0.903 R-717 4.669 4.438 0.950 R-114: SI Units 226.1 kPa 1038.8 kPa 4.59 English Units 32.8 psia 150.7 psia 4.59 CONCLUSIONS
Standard packages are designed for either R-717 or R-22 refrigerants, and feature:
It operates from -50 [degrees] F to 95 [degrees] F condensing (nominal) on R-717 and R-22 for blast cell, spiral or in-line IQF applications.
Candidates to replace R-22 included a 60-40 blend of R-32 and R-125; a 20-55-5-20 blend of R-32, R-125, R-290 and R-134a; a 10-70-20 blend of R-32, R-125 and R-134a; pure R-290 (propane), a 30-10-60 mix of R-32, R-125 and R-134a; a 35-65 blend of R-32 and R-227A; two blends (30-70, 25-75) of R-32 and R-134a; pure R-134a; and pure R-717 (ammonia).
These include HFC-134a, already used in some applications; R-290 (propane), R-717 (ammonia) and a series of blends: a 60-40 mix of HFC-32 and HFC-125; a 25-75 mix of HFC-32 and HFC-134a; a 10-70-20 mix of HFC-32, HFC-125 and HFC-134a; a 30-10-60 mix of the same three; and a 20-55-20-5 mix of those three plus propane.