共查询到20条相似文献,搜索用时 31 毫秒
1.
S. P. Chen S. L. Gao X. W. Yang Q. Z. Shi 《Russian Journal of Coordination Chemistry》2007,33(3):222-229
Thirteen solid ternary complexes Ln(Pdc)3(Phen) (Ln = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu;) have been synthesized in absolute ethanol by rare-earth
element chloride low hydrate reacting with the mixed ligands of ammonium pyrrolidinedithiocarbamate (APdc) and 1,10-phenanthroline
· H2O (o-Phen · H2O) in the ordinary laboratory atmosphere without any cautions against moisture or air sensitivity. IR spectra of the complexes
showed that the Ln3+ ion was coordinated with six sulfur atoms of three Pdc− and two nitrogen atoms of o-Phen · H2O. It was assumed that the coordination number of Ln3+ is eight. The constant-volume combustion energies of the complexes, Δc
U, were determined by a precise rotate-bomb calorimeter at 298.15 K. Their standard molar enthalpies of combustion, Δc
H
m
o
, and standard molar enthalpies of formation, Δf
H
m
o
were calculated.
The text was submitted by the authors in English. 相似文献
2.
Y. R. Zhao J. X. Dong Y. Liu S. S. Qu 《Journal of Thermal Analysis and Calorimetry》2007,90(2):565-568
The two complexes, [RE(Gly)4(Im)(H2O)](ClO4)3(s)(RE = Eu, Sm), have been synthesized and characterized. The standard molar enthalpies of reaction for the following reactions,
RECl3·6H2O(s)+4Gly(s)+Im(s)+3NaClO4(s) = =[RE(Gly)4(Im)(H2O)](ClO4)3(s)+3NaCl(s)+5H2O(l), were determined by solution-reaction colorimetry. The standard molar enthalpies of formation of the two complexes at
T = 298.15 K were derived as Δf
H
mΘ {Eu(Gly)4(Im)(H2O)}(ClO4)3(s)} = = −(3396.6±2.3) kJ mol−1 and Δf
H
mΘ {Sm(Gly)4(Im)(H2O)}(ClO4)3(s)} = −(3472.7±2.3) kJ mol−1, respectively. 相似文献
3.
R. P. Tarasov A. V. Volkov M. I. Bazanov A. S. Semeikin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(5):868-869
The energy of combustion of cobalt tetrakis(4-metoxyphenyl)porphin was determined in an isothermic-shell liquid calorimeter
with a stationary calorimetric bomb. The standard enthalpies of combustion and formation of the complex were calculated, −Δ
c
H
o = 27334.06 ± 50.98 kJ/mol and Δf
H
o = 3062.90 ± 50.97 kJ/mol.
Original Russian Text ? R.P. Tarasov, A.V. Volkov, M.I. Bazanov, A.S. Semeikin, 2009, published in Zhurnal Fizicheskoi Khimii,
2009, Vol. 83, No. 5, pp. 993–995. 相似文献
4.
Solid complexes, RE(Et2dtc)3(phen) (RE=La, Pr, Nd, Sm—Lu), were synthesized with sodium diethyldithiocarbamate (NaEt2dtc3H2O), 1,10-phenanthroline (o-phen•H2O) and hydrated lanthanide chlorides in absolute ethanol. The constant-volume combustion energies of complexes, Δ C U, were determined by a precise rotating-bomb calorimeter at 298.15 K. The standard enthalpies of combustion, ΔCHm θ, and standard enthalpies of formation, ΔfHm θ, were calculated for these complexes, respectively. The experiment results showed the “tripartite effect” of rare earth.
相似文献5.
Thermochemical
studies on the thioproline 总被引:3,自引:0,他引:3
The combustion energy of thioproline was determined
by the precision rotating-bomb calorimeter at 298.15 K to be Δc
U= –2469.30±1.44 kJ mol–1.
From the results and other auxiliary quantities, the standard molar enthalpy
of combustion and the standard molar enthalpy of formation of thioproline
were calculated to be Δc
H
m
θC4H7NO2S,
(s), 298.15 K= –2469.92±1.44 kJ mol–1
and Δf
H
m
θC4H7NO2S, (s), 298.15K= –401.33±1.54
kJ mol–1. 相似文献
6.
V. N. Emel’yanenko S. P. Verevkin C. Schick E. N. Stepurko G. N. Roganov M. K. Georgieva 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2010,84(9):1491-1497
The enthalpies of combustion and formation of S-lactic acid at 298.15 K, Δc
H
mo(cr.) = −1337.9 ± 0.8 and Δf
H
mo(cr.) = −700.1 ± 0.9 kJ/mol, were determined by calorimetry. The temperature dependence of acid vapor pressure was studied
by the transpiration method, and the enthalpy of its vaporization was obtained, Δvap
H
o(298.15 K) = 69.1 ± 1.0 kJ/mol. The temperature and enthalpy of fusion, T
m (330.4 K) and Δm
H
o(298.15 K) = 14.7 ± 0.2 kJ/mol, were determined by differential scanning calorimetry. The enthalpy of formation of the acid
in the gas phase was obtained. Ab initio methods were used to perform a conformational analysis of the acid, calculate fundamental
vibration frequencies, moments of inertia, and total and relative energies of the stablest conformers. Thermodynamic properties
were calculated in the ideal gas state over the temperature range 0–1500 K. A thermodynamic analysis of mutual transformation
processes (the formation of SS- and RS(meso)-lactides from S-lactic acid and the racemization of these lactides) and the formation
of poly-(RS)-lactide from S-lactic acid and SS- and RS(meso)-lactides was performed. 相似文献
7.
L. Peng X. Jiangjun M. Fangquan L. Xi Z. Chaocan 《Journal of Thermal Analysis and Calorimetry》2008,93(2):485-488
The standard molar enthalpy of combustion of cholesterol was measured at constant volume. According to value of Δr
U
mθ(−14358.4±20.65 kJ mol−1), Δr
H
mθ(−14385.7 kJ mol−1) of combustion reaction and Δf
H
mθ(2812.9 kJ mol−1) of cholesterol were obtained from the reaction equation. The enthalpy of combustion reaction of cholesterol was also estimated
by the average bond enthalpies. By design of a thermo-chemical recycle, the enthalpy of combustion of cholesterol were calculated
between 283.15∼373.15 K. Besides, molar enthalpy and entropy of fusion of cholesterol was obtained by DSC technique. 相似文献
8.
G. Xie S. P. Chen S. L. Gao X. X. Meng Q. Z. Shi 《Journal of Thermal Analysis and Calorimetry》2006,83(3):693-700
A novel solid complex, formulated as Ho(PDC)3
(o-phen), has been obtained from the reaction
of hydrate holmium chloride, ammonium pyrrolidinedithiocarbamate (APDC) and
1,10-phenanthroline (o-phen·H2O)
in absolute ethanol, which was characterized by elemental analysis, TG-DTG
and IR spectrum. The enthalpy change of the reaction of complex formation
from a solution of the reagents, ΔrHmθ (sol), and the molar heat capacity of the complex, cm,
were determined as being –19.161±0.051 kJ mol–1
and 79.264±1.218 J mol–1 K–1
at 298.15 K by using an RD-496 III heat conduction microcalorimeter. The enthalpy
change of complex formation from the reaction of the reagents in the solid
phase, ΔrHmθ(s), was calculated as
being (23.981±0.339) kJ mol–1 on the
basis of an appropriate thermochemical cycle and other auxiliary thermodynamic
data. The thermodynamics of reaction of formation of the complex was investigated
by the reaction in solution at the temperature range of 292.15–301.15
K. The constant-volume combustion energy of the complex, ΔcU, was determined as being –16788.46±7.74
kJ mol–1 by an RBC-II type rotating-bomb
calorimeter at 298.15 K. Its standard enthalpy of combustion, ΔcHmθ, and standard enthalpy of formation,
ΔfHmθ, were calculated to be –16803.95±7.74 and –1115.42±8.94
kJ mol–1, respectively. 相似文献
9.
Y. Xu-Wu Z. Hang-Guo S. Wu-Juan W. Xiao-Yan G. Sheng-Li 《Journal of Thermal Analysis and Calorimetry》2008,92(3):961-965
The copper(II) complex of 6-benzylaminopurine (6-BAP) has been prepared with dihydrated cupric chloride and 6-benzylaminopurine.
Infrared spectrum and thermal stabilities of the solid complex have been discussed. The constant-volume combustion energy,
Δc
U, has been determined as −12566.92±6.44 kJ mol−1 by a precise rotating-bomb calorimeter at 298.15 K. From the results and other auxiliary quantities, the standard molar enthalpy
of combustion, Δc
H
m
θ, and the standard molar of formation of the complex, Δf
H
m
θ, were calculated as −12558.24±6.44 and −842.50±6.47 kJ mol−1, respectively. 相似文献
10.
M. A. V. Ribeiro da Silva C. P. F. Santos M. J. S. Monte C. A. D. Sousa 《Journal of Thermal Analysis and Calorimetry》2006,83(3):533-539
The
standard (p0=0.1
MPa) molar enthalpies of formation, ΔfHm0, for
crystalline phthalimides: phthalimide, N-ethylphthalimide
and N-propylphthalimide were derived from
the standard molar enthalpies of combustion, in oxygen, at the temperature
298.15 K, measured by static bomb-combustion calorimetry, as, respectively,
– (318.0±1.7), – (350.1±2.7) and – (377.3±2.2)
kJ mol–1. The standard molar enthalpies of
sublimation, ΔcrgHm0, at T=298.15
K were derived by the Clausius-Clapeyron equation, from the temperature dependence
of the vapour pressures for phthalimide, as (106.9±1.2) kJ mol–1
and from high temperature Calvet microcalorimetry for phthalimide, N-ethylphthalimide and N-propylphthalimide
as, respectively, (106.3±1.3), (91.0±1.2) and (98.2±1.4)
kJ mol–1.
The derived standard molar enthalpies of formation,
in the gaseous state, are analysed in terms of enthalpic increments and interpreted
in terms of molecular structure. 相似文献
11.
Solid complexes, RE(Et2dtc)3(phen) (RE=La, Pr, Nd, Sm—Lu), were synthesized with sodium diethyldithiocarbamate (NaEt2dtc3H2O), 1,10-phenanthroline (o-phen?H2O) and hydrated lanthanide chlorides in absolute ethanol. The constant-volume combustion energies of complexes, Δ C U, were determined by a precise rotating-bomb calorimeter at 298.15 K. The standard enthalpies of combustion, ΔCHm θ, and standard enthalpies of formation, ΔfHm θ, were calculated for these complexes, respectively. The experiment results showed the “tripartite effect” of rare earth. 相似文献
12.
L. A. Kochergina A. V. Volkov E. A. Khokhlova O. N. Krutova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(5):881-889
The heat effects of the reaction of aqueous solution of L-serine with aqueous solutions of HNO3 and KOH were determined by calorimetry at temperatures of 288.15, 298.15, and 308.15 K, and ionic strength values of 0.2,
0.5, and 1.0 (background electrolyte, KNO3). Standard thermodynamic characteristics (Δr
H
o, Δr
G
o, Δr
S
o, ΔC
p
o) of the acid-base reactions in aqueous solutions of L-serine were calculated. The effect of the concentration of background
electrolyte and temperature on the heats of dissociation of amino acid was considered. The combustion energy of L-serine by
bomb calorimetry in the medium of oxygen was determined. The standard combustion and formation enthalpies of crystalline L-serine
were calculated. The heats of dissolution of crystalline L-serine in water and solutions of potassium hydroxide at 298.15
K were measured by direct calorimetry. The standard enthalpies of formation of L-serine and products of its dissociation in
aqueous solution were calculated. 相似文献
13.
T. G. Kulagina Ya. S. Samosudova I. A. Letyanina E. V. Sevast’yanov N. N. Smirnova L. A. Smirnova A. E. Mochalova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(5):747-751
The temperature dependence of the heat capacity C
p
o= f(T) 2 of 2-ethylhexyl acrylate was studied in an adiabatic vacuum calorimeter over the temperature range 6–350 K. Measurement
errors were mainly of 0.2%. Glass formation and vitreous state parameters were determined. An isothermic shell calorimeter
with a static bomb was used to measure the energy of combustion of 2-ethylhexyl acrylate. The experimental data were used
to calculate the standard thermodynamic functions C
p
o(T), H
o(T)-H
o(0), S
o(T)-S
o(0), and G
o(T)-H
o(0) of the compound in the vitreous and liquid states over the temperature range from T → 0 to 350 K, the standard enthalpies of combustion Δc
H
o, and the thermodynamic characteristics of formation Δf
H
o, Δf
S
o, and Δf
G
o at 298.15 K and p = 0.1 MPa. 相似文献
14.
S. P. Chen X. X. Meng Q. Shuai B. J. Jiao S. L. Gao Q. Z. Shi 《Journal of Thermal Analysis and Calorimetry》2006,86(3):767-774
A
solid complex Eu(C5H8NS2)3(C12H8N2) has been obtained from reaction of
hydrous europium chloride with ammonium pyrrolidinedithiocarbamate (APDC)
and 1,10-phenanthroline (o-phen⋅H2O)
in absolute ethanol. IR spectrum of the complex indicated that Eu3+
in the complex coordinated with sulfur atoms from the APDC and nitrogen atoms
from the o-phen. TG-DTG investigation provided
the evidence that the title complex was decomposed into EuS.
The
enthalpy change of the reaction of formation of the complex in ethanol, Δr
H
m
θ(l), as –22.214±0.081 kJ mol–1,
and the molar heat capacity of the complex, c
m,
as 61.676±0.651 J mol–1 K–1,
at 298.15 K were determined by an RD-496 III type microcalorimeter. The enthalpy
change of the reaction of formation of the complex in solid, Δr
H
m
θ(s), was calculated as 54.527±0.314 kJ mol–1
through a thermochemistry cycle. Based on the thermodynamics and kinetics
on the reaction of formation of the complex in ethanol at different temperatures,
fundamental parameters, including the activation enthalpy (ΔH
≠
θ),
the activation entropy (ΔS
≠
θ),
the activation free energy (ΔG
≠
θ),
the apparent reaction rate constant (k),
the apparent activation energy (E), the
pre-exponential constant (A) and the reaction
order (n), were obtained. The constant-volume
combustion energy of the complex, Δc
U,
was determined as –16937.88±9.79 kJ mol–1
by an RBC-II type rotating-bomb calorimeter at 298.15 K. Its standard enthalpy
of combustion, Δc
H
m
θ,
and standard enthalpy of formation, Δf
H
m
θ,
were calculated to be –16953.37±9.79 and –1708.23±10.69
kJ mol–1, respectively. 相似文献
15.
J. N. Zhang Z. C. Tan Q. F. Meng Q. Shi B. Tong S. X. Wang 《Journal of Thermal Analysis and Calorimetry》2009,95(2):461-467
The heat capacities (C
p,m) of 2-amino-5-methylpyridine (AMP) were measured by a precision automated adiabatic calorimeter over the temperature range
from 80 to 398 K. A solid-liquid phase transition was found in the range from 336 to 351 K with the peak heat capacity at
350.426 K. The melting temperature (T
m), the molar enthalpy (Δfus
H
m0), and the molar entropy (Δfus
S
m0) of fusion were determined to be 350.431±0.018 K, 18.108 kJ mol−1 and 51.676 J K−1 mol−1, respectively. The mole fraction purity of the sample used was determined to be 0.99734 through the Van’t Hoff equation.
The thermodynamic functions (H
T-H
298.15 and S
T-S
298.15) were calculated. The molar energy of combustion and the standard molar enthalpy of combustion were determined, ΔU
c(C6H8N2,cr)= −3500.15±1.51 kJ mol−1 and Δc
H
m0 (C6H8N2,cr)= −3502.64±1.51 kJ mol−1, by means of a precision oxygen-bomb combustion calorimeter at T=298.15 K. The standard molar enthalpy of formation of the crystalline compound was derived, Δr
H
m0 (C6H8N2,cr)= −1.74±0.57 kJ mol−1. 相似文献
16.
The novel ternary solid complex Gd(C5H8NS2)3(C12H8N2) has been obtained from the reaction of hydrous gadolinium chloride, ammonium pyrrolidinedithiocarbamate (APDC), and 1,10-phenanthroline
(o-phen · H2O) in absolute ethanol. The complex was described by an elemental analysis, TG-DTG, and an IR spectrum. The enthalpy change
of the complex formation reaction from a solution of the reagents, Δr
H
m
ϑ
(sol), and the molar heat capacity of the complex, c
m
, were determined as being − 15.174 ± 0.053 kJ/mol and 72.377 ± 0.636 J/(mol K) at 298.15 K by using an RD496-III heat conduction
microcalorimeter. The enthalpy change of a complex formation from the reaction of the reagents in a solid phase, Δr
H
m
ϑ
(s), was calculated as being 52.703 ± 0.304 kJ/mol on the basis of an appropriate thermochemical cycle and other auxiliary
thermodynamic data. The thermodynamics of the formation reaction of the complex was investigated by the reaction in solution.
Fundamental parameters, the activation enthalpy (ΔH
≠
ϑ
), the activation entropy (ΔS
≠
ϑ
), the activation free energy (ΔG
≠
ϑ
), the apparent reaction rate constant (k), the apparent activation energy (E), the preexponential constant (A), and the reaction order (n), were obtained by the combination of the thermochemical data of the reaction and kinetic equations, with the data of thermokinetic
experiments. The constant-volume combustion energy of the complex, Δc
U, was determined as being −17588.79 ± 8.62 kJ/mol by an RBC-II type rotatingbomb calorimeter at 298.15 K. Its standard enthalpy
of combustion, Δc
H
m
ϑ
, and standard enthalpy of formation, Δf
H
m
ϑ
, were calculated to be −17604.28 ± 8.62 and −282.43 ± 9.58 kJ/mol, respectively.
The text was submitted by the authors in English. 相似文献
17.
Manuel A. V. Ribeiro da Silva Ana Filipa L. O. M. Santos 《Journal of Thermal Analysis and Calorimetry》2010,100(2):403-411
This article reports the values of the standard (p
o = 0.1 MPa) molar enthalpies of formation, in the gaseous phase,
\Updelta\textf H\textm\texto ( \textg ), {{\Updelta}}_{\text{f}} H_{\text{m}}^{\text{o}} \left( {\text{g}} \right), at T = 298.15 K, of 2-acetyl-5-nitrothiophene and 5-nitro-2-thiophenecarboxaldehyde as −(48.8 ± 1.6) and (4.4 ± 1.3) kJ mol−1, respectively. These values were derived from experimental thermodynamic parameters, namely, the standard (p
o = 0.1 MPa) molar enthalpies of formation, in the crystalline phase,
\Updelta\textf H\textm\texto ( \textcr ) , {{\Updelta}}_{\text{f}} H_{\text{m}}^{\text{o}} \left( {\text{cr}} \right) , at T = 298.15 K, obtained from the standard molar enthalpies of combustion,
\Updelta\textc H\textm\texto , {{\Updelta}}_{\text{c}} H_{\text{m}}^{\text{o}} , measured by rotating bomb combustion calorimetry, and from the standard molar enthalpies of sublimation, at T = 298.15 K, determined from the temperature–vapour pressure dependence, obtained by the Knudsen mass loss effusion method.
The results are interpreted in terms of enthalpic increments and the enthalpic contribution of the nitro group in the substituted
thiophene ring is compared with the same contribution in other structurally similar compounds. 相似文献
18.
Manuel A. V. Ribeiro da Silva Luísa M. P. F. Amaral 《Journal of Thermal Analysis and Calorimetry》2010,100(2):375-380
The standard (p
o = 0.1 MPa) molar enthalpies of formation
\Updelta\textf H\textm\texto ( \textl), {{\Updelta}}_{\text{f}} H_{\text{m}}^{\text{o}} ( {\text{l),}} of the liquid 2-methylfuran, 5-methyl-2-acetylfuran and 5-methyl-2-furaldehyde were derived from the standard molar energies
of combustion, in oxygen, at T = 298.15 K, measured by static bomb combustion calorimetry. The Calvet high temperature vacuum sublimation technique was
used to measure the enthalpies of vaporization of the three compounds. The standard (p
o = 0.1 MPa) molar enthalpies of formation of the compounds, in the gaseous phase, at T = 298.15 K have been derived from the corresponding standard molar enthalpies of formation in the liquid phase and the standard
molar enthalpies of vaporization. The results obtained were −(76.4 ± 1.2), −(253.9 ± 1.9), and −(196.8 ± 1.8) kJ mol−1, for 2-methylfuran, 5-methyl-2-acetylfuran, and 5-methyl-2-furaldehyde, respectively. 相似文献
19.
I. Zięborak-Tomaszkiewicz 《Journal of Thermal Analysis and Calorimetry》2006,83(3):611-615
The energies of combustion
in fluorine of gallium nitride and indium nitride in wurzite crystalline structure
have been measured in a two-compartment calorimetric bomb, and new standard
molar enthalpies of formation have been calculated: ΔfHm0(GaN(cr)
298.15 K)= –(163.7±4.2) kJ mol–1
and ΔfHm0(InN(cr) 298.15 K)= –(146.5±4.6) kJ mol–1
. Comparison with the recommended values of the ΔfHm0 nitrides
from the literature is also presented. 相似文献
20.
Yu H. G. Yu Dong J. X. Qin C. Q. Liu Y. Qu S. S. 《Journal of Thermal Analysis and Calorimetry》2004,75(3):807-813
The energy of combustion of crystalline 3,4,5-trimethoxybenzoic acid in oxygen at T=298.15 K was determined to be -4795.9±1.3 kJ mol-1 using combustion calorimetry. The derived standard molar enthalpies of formation of 3,4,5-trimethoxybenzoic acid in crystalline
and gaseous states at T=298.15 K, ΔfHm
Θ (cr) and ΔfHm
Θ (g), were -852.9±1.9 and -721.7±2.0 kJ mol-1, respectively. The reliability of the results obtained was commented upon and compared with literature values.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献