Additivity methods for estimating heat capacities of vaporization for organic compounds

1984 ◽  
Vol 62 (2) ◽  
pp. 361-372 ◽  
Author(s):  
J. Peter Guthrie ◽  
Kathleen F. Taylor
Keyword(s):  
Standard Deviation ◽  
Level Scheme ◽  
Correlation Matrix ◽  
Heat Capacities ◽  
Organic Liquids ◽  
Group Additivity ◽  
Group Level ◽  
Average Value ◽  
Atom Level ◽  
Atom Bond

Additivity methods permitting the estimation of heat capacities of vaporization for organic liquids have been developed, using atom, bond, and group additivity parameters. Previously it had been common to use an average value for all organic liquids, which can lead to considerable errors. For the atom level scheme, 193 compounds could be fitted using 20 parameters, with a standard deviation of 1.50 cal/deg/mol, and only 29 deviations greater than 2 cal/deg/mol. For the bond level scheme, 197 compounds could be fitted using 23 parameters, with a standard deviation of 1.47 cal/deg/mol, and only 37 deviations greater than 2 cal/deg/mol. For the group level scheme, 177 compounds could be fitted using 39 parameters, with a standard deviation of 1.05 cal/deg/mol, and only 13 deviations greater than 2 cal/deg/mol. The significant terms in the correlation matrix are given for each set of parameters.

Additivity methods for estimating heats of vaporization of organic compounds

1983 ◽  
Vol 61 (3) ◽  
pp. 602-607 ◽  
Author(s):  
J. Peter Guthrie ◽  
Kathleen F. Taylor
Keyword(s):  
Standard Deviation ◽  
Organic Compounds ◽  
Correlation Matrix ◽  
Organic Liquids ◽  
Group Additivity ◽  
Group Level ◽  
Parameterization Schemes ◽  
Heats Of Vaporization

Additivity methods for heats of vaporization of organic liquids have been developed using both bond and group additivity parameters. For the bond level parameters, 429 compounds could be fitted using 36 parameters, with a weighted standard deviation of 0.32 kcal/mol, and only 23 deviations of more than 1 kcal/mol. For the group level parameters, 388 compounds could be fitted using 57 parameters, with a weighted standard deviation of 0.19 kcal/mol, and only 7 deviations of more than 1 kcal/mol. The problem of correlation among parameters is discussed and the significant terms in the correlation matrix are given. The new parameters are compared to previous parameterization schemes.

A group additivity approach for the estimation of heat capacities of organic liquids and solids at 298 K

1993 ◽  
Vol 4 (4) ◽  
pp. 261-269 ◽  
Author(s):  
James S. Chickos ◽  
Donald G. Hesse ◽  
Joel F. Liebman
Keyword(s):  
Heat Capacities ◽  
Organic Liquids ◽  
Group Additivity

PENGARUH TERAPI BACK MASSAGE TERHADAP PENURUNAN TINGKAT NYERI PADA PENDERITA RHEUMATOID ARTHRITIS DI DESA RAJADESA KECAMATAN RAJADESA KABUPATEN CIAMIS TAHUN 2018

2019 ◽  
Vol 1 (1) ◽  
pp. 1
Author(s):  
Daniel Akbar Wibowo ◽  
Dini Nurbaeti Zen ◽  
Yalis Agustina
Keyword(s):  
Rheumatoid Arthritis ◽  
Standard Deviation ◽  
Muscle Tension ◽  
Massage Therapy ◽  
Sampling Technique ◽  
Total Sample ◽  
Measurement Tool ◽  
Pain Level ◽  
Average Value ◽  
Back Massage

Disease that is often complained by the public today one of the pain in the bone, which is better known by the community with rheumatism. Rheumatism or rheumatoid arthritis is a systemic, progressive, chronic and tendonic inflammatory disease of joints and connective tissue symmetrically. One way of management of rheumatoid arthritis pain is back massage therapy. Back Massage is one of the techniques to give massage action on the back with lotions/balm for 10-15 minutes, the warm sensation leads to vasodilation of blood vessels that will improve blood circulation in the area so that the activity of the cell is increased and will reduce pain, increase comfort, reduce muscle tension and improve physical and psychological relaxation. This study aims to determine the effect of Back massage therapy to decrease the pain level of rheumatoid arthritis patients in Rajadesa Village Rajadesa Sub District Ciamis District in 2018. Type of research using Quasi Experiment Design with one group pretest-posttest design. Total sample 48 respondents with total sampling technique. Data collection using experimental method with VDS (Verbal Descriptor Scale) pain rate measurement tool. The result of statistical test by using Linear Regression shows Sig = 0,000 <0,05, t value = 18,935> 2,012. Then Ha is accepted, and the average value before therapy is 3.27 with a standard deviation of 0.818, whereas after therapy is 2.23 with a standard deviation of 0.881, meaning there is the effect of back massage therapy on the decrease of pain level in patients with rheumatoid arthritis. So to reduce pain in patients with rheumatoid arthritis can be given back massage therapy.

PENGARUH MODEL PEMBELAJARAN KELILING KELOMPOK (ROUND CLUB) TERHADAP KETERAMPILAN MENULIS LAPORAN PERJALANAN SISWA KELAS V SDN 01 NAGARI BUKIK SIKUMPA

2020 ◽  
Author(s):  
Wirda Linda
Keyword(s):  
Standard Deviation ◽  
Performance Test ◽  
Writing Skills ◽  
Learning Model ◽  
Homogeneity Test ◽  
Test Results ◽  
Class V ◽  
Average Value ◽  
Normality Test ◽  
Lecture Method

This research is motivated by the low desire of students in writing travel reports. The lack of students' knowledge of the report concept, the lack of students' knowledge of the 5W + 1H report points of good and correct language, the lack of students' knowledge of the spatial, time and topic pattern and not yet reached KKM 75. The method used by the teacher has not been interesting, lecture method. The purpose of this study is to describe the skills of writing travel reports by using Round Club learning model which is viewed from the aspect of understanding the report concept, the use of 5W +1H report points, the spatial, time, and topic pattern.The population of this study is the students of class V Lessons Year 2017/2018 which amounted to 2 classes with the number 80. The sample of research as much as two classes taken by the sample of propotional.Class V.1 as experimental class and class V.2 as control class. The research instrument used is performance test. Provide an assessment by specifying the subject of the 5W + 1H report, as well as the spatial, time and topic pattern. Data were analyzed by 't' test by first testing normality, homogeneity, and hypothesis testing.The results showed that the average control class 68 with more than enough qualifications with standard deviation 16.96. 83 experimental class with good qualification and standard deviation of 15.42 and there is a significant influence on the result of writing skill of class V SDN 01 Nagari Bukik SikumpaSubdistrict, Lima Puluh Kota. This is evidenced by the average value of writing skills in the experiment class higher than the average value in the control class. Normality test results indicate that the two sample classes of  Lo  values in the control class -0.2141 are smaller than the normal 0.190 Lt distributed. Homogeneity test results that the variation of this study is homogeneous at a real level of 0.05, because Ftable 2.16 > Fhitung 1.21 and the results of data analysis then obtained = 2.78 > 1.70 t table, so H0 rejected and H1 accepted. It can be concluded that there is Influence. Using  Learning  Model of Student Group Writing  Skills Travel Report of students of class V SDN 01 Nagari Bukik Sikumpa Subdistrict, Kabupaten Lima Puluh Kota.KeyWords: model pembelajaran round club, menulis laporan perjalanan.

Heat capacities at constant volume, free volumes, and rotational freedom in some liquids

1971 ◽  
Vol 24 (9) ◽  
pp. 1817 ◽  
Author(s):  
DD Deshpande ◽  
LG Bhatgadde
Keyword(s):  
Heat Capacity ◽  
Free Volume ◽  
Heat Capacities ◽  
Organic Liquids ◽  
Velocity Of Sound ◽  
Velocity Data ◽  
Volume Analysis ◽  
Straight Lines ◽  
Rotational Freedom ◽  
Residual Heat

This paper presents the experimental results on the velocity of sound, densities, and heat capacities of eight organic liquids at 25�, 35�, and 45�C. Using Eyring's equation, the free volumes have been calculated from the sound velocity data. For pure liquids, a quantity Cv* = (Cv)L- (Cv)g- Cstr called the residual heat capacity is found to be linearly dependent on free volume. Analysis of the data for 34 liquids shows that a plot of residual heat capacity against the free volume gives a series of straight lines differing in slopes for different groups of liquids such as hydrocarbons, halogen-substituted hydrocarbons, alcohols, etc. This behaviour is ascribed as being due to different degrees of rotational freedom of molecules in these liquids.

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