WordNet

fix or determine the value of; assign a value to; "value the jewelry and art work in the estate"
the amount (of money or goods or services) that is considered to be a fair equivalent for something else; "he tried to estimate the value of the produce at normal prices" (同)economic value
(music) the relative duration of a musical note (同)time value, note value
relative darkness or lightness of a color; "I establish the colors and principal values by organizing the painting into three values--dark, medium...and light"-Joe Hing Lowe
the quality (positive or negative) that renders something desirable or valuable; "the Shakespearean Shylock is of dubious value in the modern world"
a numerical quantity measured or assigned or computed; "the value assigned was 16 milliseconds"
an ideal accepted by some individual or group; "he has old-fashioned values"
street name for lysergic acid diethylamide (同)back breaker, battery-acid, dose, dot, Elvis, loony toons, Lucy in the sky with diamonds, pane, superman, window pane, Zen
any of various water-soluble compounds having a sour taste and capable of turning litmus red and reacting with a base to form a salt
having the characteristics of an acid; "an acid reaction"
(usually used in combination) having value of a specified kind; "triple-valued"
held in great esteem for admirable qualities especially of an intrinsic nature; "a valued friend"; "precious memories" (同)precious
beliefs of a person or social group in which they have an emotional investment (either for or against something); "he has very conservatives values"

PrepTutorEJDIC

〈U〉(…の)『価値』,値打ち,有用性,重要性《+of+名》 / 〈U〉〈C〉(…の)『価格』,値段《+of+名》 / 〈U〉〈C〉《米》《修飾語句を伴って》(払った金銭に対する)正当な値打ち / 〈C〉(単語の)意味,意義 / 〈C〉値,数値 / 〈C〉音の長短 / 〈C〉色価,(色の)明暗の度 / 〈C〉《複数形で》(道義・倫理などの)価値基準,価値観 / (ある金額に)…‘を'『評価する』,見積もる《+名+at+名〈金額〉》 / …‘を'『高く評価する』,尊重する,重んじる
酸性の / 酸味のある,すっぱい(sour) / (言葉・態度などが)厳しい,しんらつな / 酸 / すっぱいもの / 《俗》=LSD
貴重な,高く評価される,大切な

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/09/05 08:22:01」(JST)

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In chemistry, acid value (or "neutralization number" or "acid number" or "acidity") is the mass of potassium hydroxide (KOH) in milligrams that is required to neutralize one gram of chemical substance. The acid number is a measure of the amount of carboxylic acid groups in a chemical compound, such as a fatty acid, or in a mixture of compounds. In a typical procedure, a known amount of sample dissolved in organic solvent (often isopropanol), is titrated with a solution of potassium hydroxide(KOH) with known concentration and with phenolphthalein as a color indicator.

The acid number is used to quantify the amount of acid present, for example in a sample of biodiesel. It is the quantity of base, expressed in milligrams of potassium hydroxide, that is required to neutralize the acidic constituents in 1 g of sample.

V_eq is the volume of titrant (ml) consumed by the crude oil sample and 1 ml of spiking solution at the equivalent point, b_eq is the volume of titrant (ml) consumed by 1 ml of spiking solution at the equivalent point, and 56.1 is the molecular weight of KOH. W_Oil is the mass of the sample in grams.

The molar concentration of titrant (N) is calculated as such:

In which W_KHP is the mass (g) of KHP in 50 ml of KHP standard solution, V_eq is the volume of titrant (ml) consumed by 50 ml KHP standard solution at the equivalent point, and 204.23 is the molecular weight of KHP.

There are standard methods for determining the acid number, such as ASTM D 974 and DIN 51558 (for mineral oils, biodiesel), or specifically for Biodiesel using the European Standard EN 14104 and ASTM D664 are both widely used worldwide. Acid number (mg KOH/g oil) for biodiesel should to be lower than 0.50 mg KOH/g in both EN 14214 and ASTM D6751 standard fuels. This is since the FFA produced may corrode automotive parts and these limits protect vehicle engines and fuel tanks.

As oil-fats rancidify, triglycerides are converted into fatty acids and glycerol, causing an increase in acid number. A similar observation is observed with biodiesel aging through analogous oxidation processes and when subjected to prolonged high temperatures (ester thermolysis) or through exposure to acids or bases (acid/base ester hydrolysis).

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5. 出産時の臍帯血酸塩基分析 umbilical cord blood acid base analysis at delivery

English Journal

Variation in fatty acid composition of the bigeye snapper Lutjanus lutjanus collected in coral reef habitats of the Malaysian South China Sea.

Arai T1, Amalina R1, Bachok Z2.
Journal of biological research (Thessalonikē, Greece).J Biol Res (Thessalon).2015 Apr 18;22(1):5. doi: 10.1186/s40709-015-0027-2. eCollection 2015.
BACKGROUND: In order to understand trophic ecology, habitat use and migration of coral reef fish, fatty acid composition and levels were examined in the bigeye snapper Lutjanus lutjanus collected in the Malaysian South China Sea.RESULTS: Proportions of saturated fatty acids (SAFA) ranged from 55.0%
PMID 26023544

Comparison of microwave, ultrasound and accelerated-assisted solvent extraction for recovery of polyphenols from Citrus sinensis peels.

Nayak B1, Dahmoune F2, Moussi K3, Remini H4, Dairi S5, Aoun O6, Khodir M7.
Food chemistry.Food Chem.2015 Nov 15;187:507-16. doi: 10.1016/j.foodchem.2015.04.081. Epub 2015 Apr 24.
Peel of Citrus sinensis contains significant amounts of bioactive polyphenols that could be used as ingredients for a number of value-added products with health benefits. Extraction of polyphenols from the peels was performed using a microwave-assisted extraction (MAE) technique. The effects of aque
PMID 25977057

Characterization of total antioxidant capacity and (poly)phenolic compounds of differently pigmented rice varieties and their changes during domestic cooking.

Zaupa M1, Calani L1, Del Rio D1, Brighenti F1, Pellegrini N2.
Food chemistry.Food Chem.2015 Nov 15;187:338-47. doi: 10.1016/j.foodchem.2015.04.055. Epub 2015 Apr 21.
In the recent years, the pigmented rice varieties are becoming more popular due to their antioxidant properties and phenolic content. In this study, we characterized the antioxidant capacity (TAC) and the phenolic profile in white, red and black rice varieties, and evaluated the effect of two cookin
PMID 25977035

Japanese Journal

Kinetic Study of the Equilibration between Carminic Acid and Its Two Isomers Isolated from Cochineal Dye

ＣＨＥＭＩＣＡＬ　＆　ＰＨＡＲＭＡＣＥＵＴＩＣＡＬ　ＢＵＬＬＥＴＩＮ 65(3), 306-310, 2017
NAID 130005397351

Determination of <i>trans</i> Fat in Selected Fast Food Products and Hydrogenated Fats of India Using Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) Spectroscopy