凝縮熱

WordNet

provide with heat; "heat the house"
a form of energy that is transferred by a difference in temperature (同)heat energy
make hot or hotter; "the sun heats the oceans"; "heat the water on the stove" (同)heat_up
gain heat or get hot; "The room heated up quickly" (同)hot up, heat_up
the trait of being intensely emotional (同)warmth, passion
the sensation caused by heat energy (同)warmth
a preliminary race in which the winner advances to a more important race
atmospheric moisture that has condensed because of cold (同)condensate
the process of changing from a gaseous to a liquid or solid state
a shortened version of a written work (同)abridgement, abridgment, capsule
(psychoanalysis) an unconscious process whereby two ideas or images combine into a single symbol; especially in dreams
the 5th letter of the Hebrew alphabet
marked by emotional heat; vehement; "a heated argument"
made warm or hot (`het is a dialectal variant of `heated' (同)heated up, het, het_up

PrepTutorEJDIC

〈U〉『熱さ』,『暑さ』,熱い状態 / 〈U〉熱度,温度 / 〈U〉(家などの)暖房装置 / 〈U〉熱心,熱烈;(物事の)最高潮《+『of』+『名』》 / 〈U〉(エネルギーとしての)熱 / 〈C〉(競技の)1回,1ラウンド / …‘を'『熱する』,暖める《+『up』+『名,』+『名』+『up』》 / …‘を'興奮させる,怒らせる《+『up』+『名,』+『名』+『up』》 / 熱くなる,暖まる《+『up』》
（雌の）発情（in heatとして使う）・金・銭・緊迫、プレッシャー、批判、批評、警察の追跡
《所有・所属》…『の』,…のものである,…に属する・《材料・要素》…『でできた』,から成る・《部分》…『の』[『中の』] ・《数量・単位・種類を表す名詞に付いて》…の・《原因・動機》…『で』,のために(because of) ・《主格関係》…『の』,による,によって・《目的格関係》…『を』,の・《同格関係》…『という』・《関係・関連》…『についての』[『の』],の点で・《抽象名詞などと共に》…の[性質をもつ] ・《『It is』+『形』+『of』+『名』+『to』 doの形で,ofの後の名詞を意味上の主語として》・《分離》…『から』・《起原・出所》…『から』[『の』](out of) ・《『名』+『of』+『a』(『an』)+『名』の形で》…のような・《『名』+『of』+『mine』(『yours, his』など独立所有格)の形で》…の…・《時》(1)《副詞句を作って》…に《形容詞句を作って》…の・《時刻》《米》…前(to,《米》before)
〈U〉(気体から液体・固体への)凝縮,凝結,(液体の)濃縮 / 〈C〉凝縮(濃縮)されたもの / 〈U〉〈C〉(思想・表現・物語などの)縮約;縮約されたもの
彼は,彼が / 《指す人の性別が分からないか,または分かる必要のない場合に》その人,あの人,自分 / 《he who(that)の形で》《文》…するものはだれでも / (動物の)おす(雄)
鬼ごっこ(tag,tick,tig)
熱せられた / 興奮した,怒った

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/01/29 22:36:00」(JST)

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Temperature-dependency of the heats of vaporization for water, methanol, benzene, and acetone.

The enthalpy of vaporization, (symbol ∆H_vap) also known as the (latent) heat of vaporization or heat of evaporation, is the enthalpy change required to transform a given quantity of a substance from a liquid into a gas at a given pressure (often atmospheric pressure, as in STP).

It is often measured at the normal boiling point of a substance; although tabulated values are usually corrected to 298 K, the correction is often smaller than the uncertainty in the measured value.

The heat of vaporization is temperature-dependent, though a constant heat of vaporization can be assumed for small temperature ranges and for reduced temperature T_r<<1.0. The heat of vaporization diminishes with increasing temperature and it vanishes completely at the critical temperature (T_r=1) because above the critical temperature the liquid and vapor phases no longer exist, since the substance is a supercritical fluid.

Units

Values are usually quoted in J/mol or kJ/mol (molar enthalpy of vaporization), although kJ/kg or J/g (specific heat of vaporization), and older units like kcal/mol, cal/g and Btu/lb are sometimes still used, among others.

Physical model for vaporization

Fig. 1 Schematic cross section of the proposed vaporization model for monatomic liquids with one atomic surface layer.

A simple physical model for the liquid–gas phase transformation was proposed in 2009 by Jozsef Garai.^[1] It is suggested that the energy required to free an atom from the liquid is equivalent to the energy needed to overcome the surface resistance of the liquid. The model allows calculating the latent heat by multiplying the maximum surface area covering an atom (Fig. 1) with the surface tension and the number of atoms in the liquid. The calculated latent heat of vaporization values for the investigated 45 elements agrees well with experiments. Another model which utilizes the data set from Jozsef Garai's model shows that the liquid–gas phase change can be explained in terms of kinetic theory by considering that the energy required for vaporization is extracted from all six of the vaporizing molecule's neighbours. This includes a required rethink of the probability of vaporization, and has consequences to the Clausius-Clapeyron equation. Moreover, it does resolve the issue of the latent heat of vaporization being significantly greater than the thermal energy exchanged between molecules, i.e. at boiling point the latent heat for water is approximately 13.2 times kT (Boltzmann's factor multiplied by boiling temperature.)^[2]

Enthalpy of condensation

The enthalpy of condensation (or heat of condensation) is by definition equal to the enthalpy of vaporization with the opposite sign: enthalpy changes of vaporization are always positive (heat is absorbed by the substance), whereas enthalpy changes of condensation are always negative (heat is released by the substance).

Thermodynamic background

The enthalpy of vaporization can be written as

It is equal to the increased internal energy of the vapor phase compared with the liquid phase, plus the work done against ambient pressure. The increase in the internal energy can be viewed as the energy required to overcome the intermolecular interactions in the liquid (or solid, in the case of sublimation). Hence helium has a particularly low enthalpy of vaporization, 0.0845 kJ/mol, as the van der Waals forces between helium atoms are particularly weak. On the other hand, the molecules in liquid water are held together by relatively strong hydrogen bonds, and its enthalpy of vaporization, 40.65 kJ/mol, is more than five times the energy required to heat the same quantity of water from 0 °C to 100 °C (c_p = 75.3 J K⁻¹mol⁻¹). Care must be taken, however, when using enthalpies of vaporization to measure the strength of intermolecular forces, as these forces may persist to an extent in the gas phase (as is the case with hydrogen fluoride), and so the calculated value of the bond strength will be too low. This is particularly true of metals, which often form covalently bonded molecules in the gas phase: in these cases, the enthalpy of atomization must be used to obtain a true value of the bond energy.

An alternative description is to view the enthalpy of condensation as the heat which must be released to the surroundings to compensate for the drop in entropy when a gas condenses to a liquid. As the liquid and gas are in equilibrium at the boiling point (T_b), Δ_vG = 0, which leads to:

As neither entropy nor enthalpy vary greatly with temperature, it is normal to use the tabulated standard values without any correction for the difference in temperature from 298 K. A correction must be made if the pressure is different from 100 kPa, as the entropy of a gas is proportional to its pressure (or, more precisely, to its fugacity): the entropies of liquids vary little with pressure, as the compressibility of a liquid is small.

These two definitions are equivalent: the boiling point is the temperature at which the increased entropy of the gas phase overcomes the intermolecular forces. As a given quantity of matter always has a higher entropy in the gas phase than in a condensed phase ( is always positive), and from

,

the Gibbs free energy change falls with increasing temperature: gases are favored at higher temperatures, as is observed in practice.

Vaporization enthalpy of electrolyte solutions

Estimation of the enthalpy of vaporization of electrolyte solutions can be simply carried out using equations based on the chemical thermodynamic models, such as Pitzer model^[3] or TCPC model.^[4]

Selected values

Elements

v t e Enthalpies of vaporization of the elements
	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18
Group →
↓ Period
1	H 0.44936																	He 0.0845
2	Li 145.92	Be 292.40											B 489.7	C 355.8	N 2.7928	O 3.4099	F 3.2698	Ne 1.7326
3	Na 96.96	Mg 127.4											Al 293.4	Si 300	P 12.129	S 1.7175	Cl 10.2	Ar 6.447
4	K 79.87	Ca 153.6	Sc 314.2	Ti 421	V 452	Cr 344.3	Mn 226	Fe 349.6	Co 376.5	Ni 370.4	Cu 300.3	Zn 115.3	Ga 258.7	Ge 330.9	As 34.76	Se 26.3	Br 15.438	Kr 9.029
5	Rb 72.216	Sr 144	Y 363	Zr 581.6	Nb 696.6	Mo 598	Tc 660	Ru 595	Rh 493	Pd 357	Ag 250.58	Cd 100	In 231.5	Sn 295.8	Sb 77.14	Te 52.55	I 20.752	Xe 12.636
6	Cs 67.74	Ba 142		Hf 575	Ta 743	W 824	Re 715	Os 627.6	Ir 604	Pt 510	Au 334.4	Hg 59.229	Tl 164.1	Pb 177.7	Bi 104.8	Po 60.1	At 27.2	Rn 16.4
7	Fr n/a	Ra 37		Rf n/a	Db n/a	Sg n/a	Bh n/a	Hs n/a	Mt n/a	Ds n/a	Rg n/a	Cn n/a	Uut n/a	Fl n/a	Uup n/a	Lv n/a	Uus n/a	Uuo n/a

			La 414	Ce 414	Pr n/a	Nd n/a	Pm n/a	Sm n/a	Eu n/a	Gd n/a	Tb n/a	Dy n/a	Ho n/a	Er n/a	Tm n/a	Yb n/a	Lu n/a
			Ac n/a	Th 514.4	Pa n/a	U n/a	Np n/a	Pu n/a	Am n/a	Cm n/a	Bk n/a	Cf n/a	Es n/a	Fm n/a	Md n/a	No n/a	Lr n/a

	Enthalpy in in kJ/mol, measured at their respective normal boiling points
	0–10 kJ/mol			10–100 kJ/mol			100–300 kJ/mol			>300 kJ/mol

Other common substances

Enthalpies of vaporization of common substances, measured at their respective standard boiling points:

Compound	Boiling Point at normal pressure	Heat of vaporization (kJ mol⁻¹)	Heat of vaporization (kJ kg⁻¹)
Acetone	329–330 K, 56–57 °C, 133–134 °F	31.3	538.9
Aluminium	2792 K, 2519 °C, 4,566 °F (2,519 °C)	294.0	10500
Ammonia	240 K, −33.34 °C, −28 °F	23.35	1371
Butane	272–274 K, −1 °C, 30–34 °F	21.0	320
Diethyl ether	307.8 K, 34.6 °C, 94.3 °F (34.6 °C)	26.17	353.1
Ethanol	352 K, 78.37 °C, 173 °F (78 °C)	38.6	841
Hydrogen	20.271 K, -252.879 °C, −423.182 °F (−252.879 °C)	0.46	451.9
Iron	3134 K, 2862 °C, 5,182 °F (2,861 °C)	340	6090
Isopropyl alcohol	356 K, 82.6 °C, 181 °F (83 °C)	44.0	732.2
Methane	109–113 K, −164—160 °C, −263—256 °F	8.17	480.6
Methanol	338 K, 64.7 °C, 148 °F (64 °C)	35.3	1104
Propane	230.9–231.11 K,-42—42 °C, −44—44 °F	15.7	356
Phosphine	185 K, −87.7 °C, −126 °F	14.6	429.4
Water	373.15 K, 100 °C, 212 °F (100 °C)	44.00	2260 @ 98.64 °C ^[5]

References

^ Garai, J. (2009). "Physical model for vaporization". Fluid Phase Equilibria 283: 89–77. doi:10.1016/j.fluid.2009.06.005. edit
^ K. Mayhew, Phys. Essays 26, vol 4, 604 (2013)
^ X. Ge, X. Wang. Estimation of Freezing Point Depression, Boiling Point Elevation and Vaporization enthalpies of electrolyte solutions. Ind. Eng. Chem. Res. 48(2009)2229–2235. http://pubs.acs.org/doi/abs/10.1021/ie801348c (Correction: 2009, 48, 5123)http://pubs.acs.org/doi/abs/10.1021/ie900434h
^ X. Ge, X. Wang. Calculations of Freezing Point Depression, Boiling Point Elevation, Vapor Pressure and Enthalpies of Vaporization of Electrolyte Solutions by a Modified Three-Characteristic Parameter Correlation Model. J. Sol. Chem. 38(2009)1097–1117.http://www.springerlink.com/content/21670685448p5145/
^ Çengel, Yunus A., and Michael A. Boles. "Appendix 1." Thermodynamics: An Engineering Approach. 7th ed. Boston: McGraw-Hill, 2011. 914. Print.

CODATA Key Values for Thermodynamics
Kugler HK & Keller C (eds) 1985, Gmelin handbook of inorganic and organometallic chemistry, 8th ed., 'At, Astatine', system no. 8a, Springer-Verlag, Berlin, ISBN 3-540-93516-9, pp. 116–117
NIST Chemistry WebBook
Sears, Zemansky et al., University Physics, Addison-Wesley Publishing Company, Sixth ed., 1982, ISBN 0-201-07199-1

UpToDate Contents

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1. 小児における熱射病 heat stroke in children
2. 小児における熱中症（熱射病を除く） heat illness other than heat stroke in children
3. 成人における重度高熱（熱射病） severe hyperthermia heat stroke in adults
4. 人工呼吸器回路と人工呼吸器関連肺炎 the ventilator circuit and ventilator associated pneumonia
5. 過負荷による（慢性）腱障害の管理の概要 overview of the management of overuse chronic tendinopathy

English Journal

Investigation of Structural Modification and Thermal Characteristics of Lignin after Heat Treatment.

Kim JY1, Hwang H1, Oh S1, Kim YS2, Kim UJ3, Choi JW4.Author information 1Department of Forest Sciences and Research Institute for Agriculture and Life Science, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul, 151-921, Korea.2Division of Wood Chemistry & Microbiology, Korea Forest Research Institute, 57 Hoegi-ro, Dongdaemun-gu, Seoul, 130-712, Korea.3Department of Plant & Environmental New Resources, College of Life Science, KyungHee University, Yongin-si, Kyunggi-do, 446-701, Korea.4Department of Forest Sciences and Research Institute for Agriculture and Life Science, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul, 151-921, Korea. Electronic address: cjw@snu.ac.kr.AbstractMilled wood lignin was subjected to heat treatment between 150 and 300°C to understand the pattern of its structural modification and thermal properties. When the temperature was elevated with interval of 50°C, the color of the lignin became dark brown and the lignin released various forms of phenols from terminal phenolic groups in the lignin, leading to two physical phenomena: 1) gradual weight loss of the lignin, up to 19% based on dry weight; and 2) increase in the carbon content and decrease in the oxygen content. Nitrobenzene oxidation ans 13C-NMR analyses confirmed a cleavage of β-O-4 linkage (depolymerization) and reduction of methoxyl as well as phenolic hydroxyl group were also characteristic in the lignin structure during heat treatment. Simultaneously with lignin depolymerization, GPC analysis provided a possibility that condensation between lignin fragments could also occur during heat treatment. TGA/DTG/DSC data revealed that thermal stability of lignin obviously increased after heat treatment, implicating the structural rearrangement of lignin to reduction of β-O-4 linkage as well as accumulation of C-C bonds.
International journal of biological macromolecules.Int J Biol Macromol.2014 Feb 13. pii: S0141-8130(14)00097-X. doi: 10.1016/j.ijbiomac.2014.02.013. [Epub ahead of print]
Milled wood lignin was subjected to heat treatment between 150 and 300°C to understand the pattern of its structural modification and thermal properties. When the temperature was elevated with interval of 50°C, the color of the lignin became dark brown and the lignin released various forms of phen
PMID 24530642

Condensation on Surface Energy Gradient Shifts Drop Size Distribution toward Small Drops.

Macner AM, Daniel S, Steen PH.Author information School of Chemical and Biomolecular Engineering, Cornell University , Ithaca, New York 14853, United States.AbstractDuring dropwise condensation from vapor onto a cooled surface, distributions of drops evolve by nucleation, growth, and coalescence. Drop surface coverage dictates the heat transfer characteristics and depends on both drop size and number of drops present on the surface at any given time. Thus, manipulating drop distributions is crucial to maximizing heat transfer. On earth, manipulation is achieved with gravity. However, in applications with small length scales or in low gravity environments, other methods of removal, such as a surface energy gradient, are required. This study examines how chemical modification of a cooled surface affects drop growth and coalescence, which in turn influences how a population of drops evolves. Steam is condensed onto a horizontally oriented surface that has been treated by silanization to deliver either a spatially uniform contact angle (hydrophilic, hydrophobic) or a continuous radial gradient of contact angles (hydrophobic to hydrophilic). The time evolution of number density and associated drop size distributions are measured. For a uniform surface, the shape of the drop size distribution is unique and can be used to identify the progress of condensation. In contrast, the drop size distribution for a gradient surface, relative to a uniform surface, shifts toward a population of small drops. The frequent sweeping of drops truncates maturation of the first generation of large drops and locks the distribution shape at the initial distribution. The absence of a shape change indicates that dropwise condensation has reached a steady state. Previous reports of heat transfer enhancement on chemical gradient surfaces can be explained by this shift toward smaller drops, from which the high heat transfer coefficients in dropwise condensation are attributed to. Terrestrial applications using gravity as the primary removal mechanism also stand to benefit from inclusion of gradient surfaces because the critical threshold size required for drop movement is reduced.
Langmuir : the ACS journal of surfaces and colloids.Langmuir.2014 Feb 13. [Epub ahead of print]
During dropwise condensation from vapor onto a cooled surface, distributions of drops evolve by nucleation, growth, and coalescence. Drop surface coverage dictates the heat transfer characteristics and depends on both drop size and number of drops present on the surface at any given time. Thus, mani
PMID 24490757

Faox enzymes inhibited Maillard reaction development during storage both in protein glucose model system and low lactose UHT milk.

Troise AD, Dathan NA, Fiore A, Roviello G, Di Fiore A, Caira S, Cuollo M, De Simone G, Fogliano V, Monti SM.Author information Dipartimento di Scienza degli Alimenti, Università degli Studi di Napoli Federico II Via Salute, Parco Gussone Superiore, Portici (Naples), Italy.AbstractFructosamines, also known as Amadori products, are formed by the condensation of glucose with the amino group of amino acids or proteins. These compounds are precursors of advanced glycation end products (AGEs) that can be formed either endogenously during aging and diabetes, and exogenously in heat-processed food. The negative effects of dietary AGEs on human health as well as their negative impact on the quality of dairy products have been widely described, therefore specific tools able to prevent the formation of glycation products are needed. Two fructosamine oxidase enzymes isolated from Aspergillus sp. namely, Faox I and Faox II catalyze the oxidative deglycation of Amadori products representing a potential tool for inhibiting the Maillard reaction in dairy products. In this paper, the ability of recombinant Faox I and II in limiting the formation of carboxy-methyl lysine (CML) and protein-bound hydroxymethyl furfurol (b-HMF) in a commercial UHT low lactose milk and a beta-lactoglobulin (β-LG) glucose model system was investigated. Results show a consistent reduction of CML and b-HMF under all conditions. Faox effects were particularly evident on b-HMF formation in low lactose commercial milk. Peptide analysis of the β-LG glucose system identified some peptides, derived from cyanogen bromide hydrolysis, as suitable candidates to monitor Faox action in milk-based products. All in all data suggested that non-enzymatic reactions in dairy products might be strongly reduced by implementing Faox enzymes.
Amino acids.Amino Acids.2014 Feb;46(2):279-88. doi: 10.1007/s00726-013-1497-x. Epub 2013 Apr 21.
Fructosamines, also known as Amadori products, are formed by the condensation of glucose with the amino group of amino acids or proteins. These compounds are precursors of advanced glycation end products (AGEs) that can be formed either endogenously during aging and diabetes, and exogenously in heat
PMID 23604465