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Volume 10 (1983)
- Issue 4 Pages 127-
- Issue 3 Pages 91-
- Issue 2 Pages 43-
- Issue 1 Pages 2-
Volume 10, Issue 3
Displaying 1-6 of 6 articles from this issue
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Guang Xue Zhong, Jie Ru Shen, Peng Ou Guo, Ji Xiang He1983 Volume 10 Issue 3 Pages 91-96
Published: July 31, 1983
Released on J-STAGE: September 07, 2009
JOURNAL FREE ACCESSIn this work the combination of the refrigeration technique by semiconductors with calorimetry is proved to be effective through the development of a versatile semiconductor calorimetric system and the calorimetric measurements with it. Self-made semiconductor thermoelectric sensors and a semiconductor thermostat were used in this calorimetric system. The thermostat operates in a temperature range from 0 to 60°C. The sensitivity of the sensor is 25mV K-1 (not amplified). The versatility of this system has been demonstrated in the ability to make precision measurements in adiabatic or in isoperibol mode. The precision of measurements is about 0.06%. The value for the specific heat capacity of water, cp (298.15K), was obtained to be (4.176±0.013)JK-1 g-1 for measurements with the adiabatic calorimeter, and for the enthalpy of solution of KCl, ΔsolH(200 H2O, 298.15K) was (17.56±0.01) kJ mol-1 for measurements with the isoperibol calorimeter. These results are in good agreement with the values recommended by the Physical Chemistry Division of IUPAC in 1974.View full abstractDownload PDF (676K) -
Akira Inaba1983 Volume 10 Issue 3 Pages 97-102
Published: July 31, 1983
Released on J-STAGE: September 07, 2009
JOURNAL FREE ACCESSA capsule-type standard platinum resistance thermometer was constructed, which is applicable to high accuracy measurements of heat capacity between 70K and 700K. A doubly coiled element is installed on a fused silica cross with strain-free construction in a platinum capsule, and four platinum leads are brought out through ceramic seals. After stability testing, the thermometer was calibrated based on the IPTS-68 by using standard calibration apparatus: It has an ice-point resistance of about 26.0Ω and a steam-point resistance ratio of 1.392 494 as determined by a d-c resistance bridge. A separate experiment for calibration was performed in the calorimeter (in situ), when an a-c resistance bridge and small-sized triple-point cells of Ga, In and Zn were employed. The resistance ratio at steam point was determined to be 1.392 543, being different from that obtained by the d-c measurement. The systematic errors in the a-c measurement of the thermometer resistance are evaluated by a couple of calibration experiments.View full abstractDownload PDF (842K) -
III. Gibbs Energies and Entropies of Inclusion of 1-Propanol and 1-Pentanol into Cyclohexaamylose and Cycloheptaamylose in Aqueous Solutions at 298.15KMune Maeda, Sadao Takagi1983 Volume 10 Issue 3 Pages 103-107
Published: July 31, 1983
Released on J-STAGE: September 07, 2009
JOURNAL FREE ACCESSFor the molecular inclusion equilibrium between cyclohexaamylose and 1-propanol or 1-pentanol with a 1:1 inclusion complex in dilute aqueous solution: (CyD)aq+(ROH)aq _??_ (CyD·ROH)aq, the equilibrium constant K and the limiting molar ratio ymax of the alcohol included have been refined by the improved version of procedures which were proposed by the present authors [original, Nippon Kagaku Kaishi, 1983, 188; the improved version, Netsusokutei, 10, 43 (1983)]. The most probable values refined for log10K and ymax are 3.124 and 0.495 for C3H7OH, and 4.265 and 0.785 for C5H11OH, respectively.
From these results and those for cycloheptaamylose and the same alcohols reported earlier by the present authors, the enthalpies, Gibbs energies, and entropies of inclusion have been evaluated. The entropy changes are positive in all systems, showing that common “driving-force” is the increase of the entropy. The enthalpy changes are, however, exothermic for the inclusion into the rather small cavities of cyclohexaamylose, but are endothermic for the inclusion into the larger cavities of cycloheptaamylose in aqueous solutions.View full abstractDownload PDF (531K) -
Takasuke Matsuo1983 Volume 10 Issue 3 Pages 108-114
Published: July 31, 1983
Released on J-STAGE: September 07, 2009
JOURNAL FREE ACCESSPrecision bridges and potentiometers developed recently for resistance thermometry are reviewed with emphasis on the principles of their operation. Direct current apparatus discussed include potentiometers of the Lindek type and flux-coupled direct current comparator, both capable of resolution at nanovolt level. Amplifier-null detectors are also discussed. Different types of alternating current bridges are described. They differ in the principle on which the transformers work. Advantage of self-balancing AC bridges in an automatic calorimeter controlled by a microcomputer is shown with an example of noise reduction by averaging.View full abstractDownload PDF (974K) -
III. Calorimetry of non-isothermal processesY. Takahashi, M. Kamimoto1983 Volume 10 Issue 3 Pages 115-123
Published: July 31, 1983
Released on J-STAGE: September 07, 2009
JOURNAL FREE ACCESSDownload PDF (1308K) -
Y. Watanabe1983 Volume 10 Issue 3 Pages 124
Published: July 31, 1983
Released on J-STAGE: September 07, 2009
JOURNAL FREE ACCESSDownload PDF (155K)
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