The result shows that the predicted critical volumes agree with the experimental data satisfactorily,the mean relative deviation is 1.88%, less than that of the group contribution method.

Taking temperature as input vector and solubility as output vector to set up radial basis function artificial neural networks, the results indicate that RBF can fast realize convergence approaching a function. The mean relative deviation of train aggregate is 0.81%, and test aggregate is 1.64%.

By using the NRTL equation for non-electrolyte solution, the VLE isotherms for [bmim][PF_6]-H_2O and [C_8mim][PF_6]-H_2O binary systems were correlated with deviation within 2% and the VLE data at other temperatures were predicted with the mean relative deviation within 5%.

The results calculated show that the predicted values of boiling pointsagree with the experimental data satisfactorily. and the mean relative deviation is only0.05%。

The results calculated show that the predicted values of densities are in good agreement with the experimental data, and the mean relative deviation is 0. 053%, the mean absolute deviation is 0.00058 (M,a.m-3. Not only can the quantitative relation predict the densities of normal 1 -bromoalkane but can help to discover the secret among the structure -property relationship of matter.

From comparison of calculated value and experimental data, the average of AAD (Overall-average deviation) of binary LLE calculation for 10 systems containing ILs is 3. 228% with NRTL model and 2. 691% with UNIQUAC model.

Results: The [η] obtained from Solomon-Ciuta's equation and Maron's equation are in good agreement with that obtained from Huggins' equation with a maximum relative deviation of <0.8% and < 0.7 % respectively.

A mathematical model to calculate chemical exergier was established by group connectivity index,which has a simplest form such as E~0_(x.ch)(kJ/mol)=(1 681.831 5)(~1Ψ) +807.976 2.It was shown that the largest error is not higer than 0.28% and mean relative error is not more than 0.069% for selected substances.

The mean difference between the theoretical and experimental frequencies was found to be 19.0 cm~-1. According to the normal modes and IR intensities in DFT calculation, we gave a consummate and reasonable assignment and interpretation to the observed vibrational spectrum of strychnine.

It shows that the overall mean relative deviation (OMRD) of the Dodge-Metzner correlation is the minimum, 1.5%.

The system's pressure resulting from aT x →p calculation procedure can be represented with a mean relative deviation of 1.3%.

The mean relative deviation from the lab method calculated according to Hill was 6.87% for INRatio?, which is rated "very goo", and 9.72% for Coaguchek? S ("goo").

The mean relative deviation is between -2 to 15% between 15 and 35 km altitude, which is a quite promising result.

The most representative mechanism with respect to average predictions is SAPRC99, with a mean relative deviation of 12%.

A simplified volumetric method for the determination of sulfur in organic compounds is described. The results obtained by this method are in agreement with those obtained by the gravimetric method, The method is stated as following: Weigh accurately a sample containing 30—75 mg SO_4~- into a nickel crucible containing 1 g. of KNO_3 and 8 g. of KOH. Heat the crucible carefully with a small flame until the contents melt, increase the heat gradually until the decomposition is complete. Leach the melt with water,...

A simplified volumetric method for the determination of sulfur in organic compounds is described. The results obtained by this method are in agreement with those obtained by the gravimetric method, The method is stated as following: Weigh accurately a sample containing 30—75 mg SO_4~- into a nickel crucible containing 1 g. of KNO_3 and 8 g. of KOH. Heat the crucible carefully with a small flame until the contents melt, increase the heat gradually until the decomposition is complete. Leach the melt with water, acidify with HCl and heat gently until bubbles cease to evolve. Filter, dilute the filtrate to about 60 ml. and after neutralizing with 6 N NH_4OH, add 0.2 ml. 6 N HCl. Heat to 70℃, add gradually the benzidine hydrochloride reagent to precipitate the sulfate in the solution. After cooling in an ice bath for 1 hour, the precipitate is filtered from the solution. Suspend the precipitate in water, heat to 80℃ and titrate with 0.1 N NaOH solution, using phenolphthalein as indicator.

A chromatographic analytical procedure has been developed for the gaseous impurities in concentrated acetylene gas manufactured from natural gas.In this work a thermal conductivity detector,a potentiometer recorder,and hydrogen as carrier gas were used. Column I packed with a mixture of salicylaldehyde and liquid paraffin as stationary liquid was used to separate and analyse the components such as allene,methylacetylene, butadiene,vinylacetylene,and diacetylene.The time required for a complete analysis is about...

A chromatographic analytical procedure has been developed for the gaseous impurities in concentrated acetylene gas manufactured from natural gas.In this work a thermal conductivity detector,a potentiometer recorder,and hydrogen as carrier gas were used. Column I packed with a mixture of salicylaldehyde and liquid paraffin as stationary liquid was used to separate and analyse the components such as allene,methylacetylene, butadiene,vinylacetylene,and diacetylene.The time required for a complete analysis is about 18 minutes. Column Ⅱ containing a serial packing of adsorbents of active carbon and Type 5A molecular sieve was used to analyse oxygen,nitrogen,methane,and carbon monoxide. Carbon dioxide,ethylene,and acetylene were analysed on column Ⅲ filled with active carbon and silica gel in series.Samples were injected separatively.The total time of analysis is about 20 minutes. The results of determination and computation indicate that the minimum detectable quantity of gaseous impurities is 1.16—36 ppm.With impurities ranging from 0.005 to 0.5％,the reproducibility expressed as relative average deviation is less than ±10％,and the accuracy expressed as relative average error is less than ±5％.

A group-contribution technique was proposed for predicting solubility parameter.98 group increments were determined by regression of 441 experimental data,which were carefully selected from a large database. The average absolute deviation for the 441 experi-mental data is 2.3%.