Triangular Diagram Research Articles

On the value of relative flow data

Abstract Traffic flow can be described using three dimensions, i.e., space x, time t and cumulative flow N. This study considers estimating the cumulative flow over space and time, i.e., N ( x , t ) , using relative flow data collected by stationary and moving observers. Stationary observers, e.g., loop-detectors, can observe flow at fixed position over time. Furthermore, automated or other equipped and connected vehicles can serve as moving observers that observe flow relative to their position over time. To present the value of relative flow data, in this paper, we take the perspective of a model-based estimation approach. In this approach, the data is used in two processes: (1) information assimilation of real-time data and models and (2) learning of the models used in information assimilation based on historical data. This paper focuses on traffic state estimation on links. However, we explain that, in absence of stationary observer that are positioned at the link boundaries, it is valuable to consider the information propagation over nodes. Throughout this study a LWR-model with a triangular fundamental diagram (FD) is used to develop the principles that can be used for the two processes. These principles are tested in a simulation (VISSIM) study. This study shows that we can find the traffic flow model parameters and can partially estimate the link boundary conditions based on relative flow data collected by moving observers alone. It also shows that the traffic flow behavior differs partially from the LWR-model with triangular FD, and therefore, we recommend the option to learn and use other traffic flow models in future research. Overall, relative flow data is considered valuable to obtain model learning datasets and to estimate the traffic state.

Major Ionic Features and Possible Controls in the Groundwater in the Hamatong River Basin

In order to study the major ion chemistry and controls of groundwater, 59 groundwater samples were collected and their major ions measured in the Hamatong River Basin. The hydrogeochemical characteristics of groundwater in this basin were analyzed by means of mathematical statistics, Piper triangular diagrams, Gibbs figures, and ionic relations, and the water chemical evolution and ion sources of the Hamatong River Basin were determined. The results showed that Ca2+ was the main cation in the groundwater, accounting for 22.1% to 72.4% of the total cations, with an average value of 48.7%. HCO3- was the main anion, accounting for 35.3% to 97.5% of the total anions, and with an average value of 80%. Total dissolved solids concentration ranged from 93.3 mg·L-1 to 521.1 mg·L-1 with a median value of 219.1 mg·L-1. The hydrochemical types of groundwater are HCO3-Ca, HCO3-Ca·Mg, and HCO3-Ca·Na. Chemical weathering rates of carbonates and silicates were estimated, and the chemical composition of groundwater samples located in the middle of Gibbs model indicated that the major chemical process of groundwater was controlled by rock weathering. Silicate weathering is believed to significantly contribute to dissolved solute compositions, and carbonate weathering played an important role as the source of dissolved ions.

Phenanthrene biomarkers in the organic matter of Precambrian and Phanerozoic deposits and in the oils of the Siberian Platform

The composition and distribution of phenanthrenes (polyaromatic compounds) have been studied in chloroform extracts from dispersed organic matter (OM) of clayey, siliceous, carbonate, and terrigenous rocks of different ages and facies and from some oils of the Siberian Platform. Phenanthrenes have been analyzed by gas chromatography-mass spectrometry. High contents of 1,7,8-trimethylphenanthrene and 1,1,7,8-tetramethyl-1,2,3,4-tetrahydrophenanthrene are present in the OM of Vendian and Cambrian carbonate-shale deposits and in ancient oils of the Nepa-Botuobiya and Anabar anteclises. The OM of Permian continental deposits and oils of the Vilyui syneclise is dominated by 1-methyl-7-isopropylphenanthrene (retene). A triangular diagram for identification of the types of original OM of rocks and classification of genetically related oils has been constructed based on the assessment of phenanthrene biomarker distribution. Putative pathways of the formation of phenanthrene biomarkers are discussed.

MOBILE ACCUMULATORS FOR DISCRETE SYSTEMS HEAT-COLD SUPPLIES. Part 2.

The purpose of this article is selection and substantiate the construct materials for a mobile battery of thermal energy. To evaluate the impact of chemical corrosion on the structural materials of the tank-battery, and researching the strength of the tank-battery during transportation and determination the feasibility of introducing and effectiveness of investments in environmental measures on the example of the implementation of the discrete heating / cooling systems. A comparison has been made of the technical characteristics chosen for our studies of heat storage material - bischofite and sodium acetate trihydrate, which showed that both substances have certain advantages and limitations in their application. An experiment was carried out to determine the stability of the material for corrosion, after the 10 cycles of heating-cooling, the metal parts that were deposited in the bischofite solution remained virtually unchanged, no corrosion marks were observed. While specimens that were in the melt of sodium triacetate have obvious corrosion marks (except for a stainless steel sample). Particularly noticeable corrosion of samples that were on the verge of air and sodium triacetate. Thus, it has been confirmed that the use of hydrated salt melts requires additional measures to protect against corrosion of metals, and the use of polymer materials is limited by the temperature of their application. Calculations of the strength of the tank-accumulator at static and dynamic loads with the account of transportation are carried out. Taking into account the obtained results of Mises stress, the tensile stresses in the cut and stresses of bolted joints during rolling during transport under conditions of use of steel constructions are higher. In the course of determining the feasibility of implementing the project, it was tested and proposed to supplement the methods of calculating the investment of energy saving measures and projects by a fundamentally new method of strategic rapid analysis "3E". This method allows you to get a graphical representation of the result of the analysis and with a high degree of probability to determine the strategy of financing the implementation projects. The analysis is based on three main criteria, namely: energy, environmental and economic. These weighting criteria consist of a number of values that are necessary to obtain a likely return on the payback of the implementation project. The results of express analysis are clearly represented in the form of the area of permissible values on the triangular diagram, which we are invited to call the "3E triangle" in the initial words of words: Energy, Ecology and Economics. An economic analysis has also been conducted, which showed that the estimated payback period of the project is less than five years, and the volume of annual revenue from the sale of thermal energy and cold is 1470000 UAH. Thus, the project is attractive for investment.

Development of high flux ultrafiltration polyphenylsulfone membranes applying the systems with upper and lower critical solution temperatures: Effect of polyethylene glycol molecular weight and coagulation bath temperature

A novel phase inversion technique for preparation of high flux polyphenylsulfone (PPSU) ultrafiltration membranes employing the systems which feature upper critical solution temperature (UCST), gel point and lower critical solution temperature (LCST) is proposed. These systems include PPSU, polyethylene glycol (PEG) with molecular weight in the range of 6 ÷ 40 × 103 g mol−1 and N-methyl-2-pyrrolidone (NMP) as a solvent. According to the triangular phase diagrams obtained, the polymer solutions consisting of 20 wt% PPSU – 15 wt% PEG (Mw = 6 ÷ 40 × 103 g mol−1) – NMP are revealed to be two-phase systems at T > 100 °C and gels at T < 38–40 °C. The developed technique involves PPSU solution processing at the temperature region between LCST and UCST (gel point). Meanwhile, the coagulation bath temperature has to be between UCST (gel point) and LCST. The effect of PEG molecular weight, casting solution composition and coagulation bath temperature on membrane structure, performance and hydrophilic-hydrophobic balance of the membrane selective layer was studied. Applying the proposed technique flat-sheet membranes with pure water flux of 486 L m−2 h−1 bar−1 and human serum albumin rejection of 90% were prepared which is the best performance for PPSU ultrafiltration membranes reported up-to-date. It was found that introduction of PEG (Mw = 6 ÷ 40 × 103g mol−1) into the casting solution results in the efficient membrane hydrophilization, which is confirmed by FTIR spectroscopy of the membrane selective layer.

Hydrogeochemistry of Isti Su hot spring, Western Azerbaijan, Iran

The Isti Su hot spring is located in southeast of Salmas, in Western Azerbaijan, Iran. The area is a small part of Sanandaj–Sirjan geological zone which hosts many hot springs. The magma chamber of Salmas region is the main heat source of the hot springs in Isti Su area. Abundant rainfall and relatively long duration of snowfall as well as several deep faults in the area create the best conditions to have several hot springs in the area. The host rocks of the area are sedimentary and metamorphic rocks of Cambrian to Recent sediments which are intruded by several granite and ophiolite bodies. Several hot springs have been formed in the vicinity of these plutonic to sub-volcanic bodies. The Isti Su hot spring is one of the most typical hot springs of the Salmas region. Eight samples were collected from the study area. To investigate the seasonal changes in the field and chemical parameters and to measure trace element concentrations in dry and wet seasons, springs were sampled twice in May and November. Temperature, pH and electrical conductivity of the water samples were measured on-site. Temperatures of the selected samples range from 26.3 to 38.5 °C. The pH values of the samples vary between 6.4 and 7.5. TDS contents range from 9200 to 1790 mg/L. The results of geochemical analysis show that the As, Li, Fe, Hg, Na, and Cr are not more than WHO’s standard level. As and B are two times more than WHO’s standard level. The As and B concentrations in the hydrothermal and geothermal solutions rise higher than its standard level. World Health Organization recommended As level for drinking water is 0.01 mg/L. The Na–SO4–HCO3 triangular diagram shows that the samples are of HCO3 and Na types. Open skin scars, gangrene, malignant cancers and environmental problems are among the consequences of high concentrations of As and B. The high content of As and B in water of this hot spring can be harmful to the environment and people of the area.

Preparation of dye-grafted-silica/poly(acrylate) color coatings with enhanced color stability at elevated temperatures

PurposeThe purpose of this paper is to investigate the effects of dipentaerythritol hexaacrylate (DPHA) and 3-(trimethoxysilyl)propyl methacrylate-modified silica nanoparticles (MSiO2) contents on the performances of the Disperse Red 1 (DR1)-grafted-silica/poly(acrylate) color hard coatings.Design/methodology/approachThe organic dye DR1 was silylated by reaction with the coupling agent 3-isocyanatopropyltriethoxysilane in methyl ethyl ketone. The silylated-DR1 thus obtained was grafted on MSiO2 to form dye-grafted silica (GSiO2). This hybrid dye was then UV-cured with the cross-linking agent, DPHA, to yield color coatings. Thermal durability of the coatings was evaluated based on their CIE (international commission on illumination) chromaticity coordinates and UV/Vis transmittances.FindingsThe results indicated that GSiO2-coatings could tolerate thermal attack better than pristine DR1-coatings or dye-absorbed silica (DSiO2)-coatings because of the fact that DR1 was more finely dispersed in the polymer binder when covalently bonded to the silica particles. Under optimal conditions, coatings with very small change of saturation and hue after high-temperature treatments were obtainable. These coatings appeared transparent, had 3H-6H pencil hardness and adhered perfectly onto the poly(methyl methacrylate) substrates.Practical implicationsDye-grafted color coatings may find applications such as color filter photoresists for displays, microelectronics, printed circuit boards, etc.Originality/valueThe performances of the coatings were evaluated in terms of mechanical strength, adherence to the substrate, transmittance and color stability against heat treatments, which have not been disclosed. Also, using a newly developed triangular composition diagram, suitable ranges for preparing useful color coatings were accessed. The present method deserves further research studies on green and blue dyes.

Electromagnetic Interactions of Mesons and the πa1 Diagonalization

It has been demonstrated that, contrary to the commonly accepted viewpoint, electromagnetic interactions cannot be consistently included in the Nambu–Jona-Lasinio model within vector meson dominance. This refers to the procedure for removing the πa1 transition in the effective meson Lagrangian. By the example of the a1(1260)→γπ+π- radiative decay, it has been demonstrated that the gauge invariance condition for the amplitude gives rise to an electromagnetic vertex describing the direct emission of a photon and a pion by a quark–antiquark pair. Surface terms appearing in the calculation of an anomalous triangular quark diagram, where one of the vertices is the interaction violating the vector-dominance hypothesis, play a key role in satisfying the Ward identities.

Morphology and chemistry of placer gold in the Bagrote and Dainter streams, northern Pakistan: Implications for provenance and exploration

The Bagrote and Dainter valleys in Gilgit Baltistan Pakistan, belonging to the Kohistan island arc and southwestern domain of the Karakorum metamorphic complex, respectively, are a location of regional placer gold mining. However, no in situ hydrothermal gold deposits have been discovered in this region. Here, we report the textural, morphological, and geochemical characteristics of placer gold from the stream sediments of the Bagrote and Dainter valleys with a view to trace the provenance. The morphological features of the studied gold grains indicate proximal source mineralization. The gold grains display a microtexture typical of mechanical abrasion rather than chemical activity. Their chemical composition of most of the grains from each stream falls in a restricted range (minor alloying elements mainly Cu) with high fineness (1,000 Au/(Au + Ag)), suggesting derivation from a homogeneous source or limited number of mineralization types. The high Cu content of the gold grains from the Bagrote stream suggests that the gold here might be associated with previously undiscovered porphyry gold mineralization, whereas the Au–Ag–Hg alloys from the Dainter stream suggest a genetic linkage with undiscovered fault‐controlled auriferous veins of epithermal origin in the southwestern part of the Karakorum metamorphic complex. The chemical composition of both streams placer gold in triangular diagram in terms of Au–Ag–Cu shows all the gold grains from Dainter stream were derived from epithermal type of mineralization, and most of the plots of Bagrote stream fall on the domain of porphyry epithermal type of deposits which are also in consistent with a continental arc setting in the study area. The mechanically developed microtexture, homogeneous chemical composition in individual grains from core to rim, and absence of high fineness rims of the gold grains from both streams, suggest the absence of any supergene regrowth and direct transfer from the primary source through glacier to the fluvial system. The Gilgit Baltistan province, dominated by dry temperate climate and glacial environment having steep geomorphology, precluding any significant supergene processes such as silver leaching and addition of authigenic gold on detrital gold grains.

Triangular exchange diagram within the full off-shell Coulomb T-matrix in deuteron induced reactions

&lt;span&gt;The amplitude of the triangular diagrams in the three-body models of deuteron induced reactions &lt;span&gt;with charged particles contains the off-shell two-body &lt;span&gt;&lt;em&gt;T&lt;/em&gt;&lt;span&gt;-matrix describing the intermediate-state &lt;span&gt;Coulomb scattering of charged subsystems. Up to now the latter has usually been replaced by the &lt;span&gt;Coulomb potential due to the computational reason. In this paper, we first investigate theoretically &lt;span&gt;and numerically the validity of the mentioned Coulomb-Born approximation. The results show the &lt;span&gt;important contribution of the higher order of the latter approximation for the (d,p) reactions off &lt;span&gt;heavy target.&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;br /&gt;&lt;br class="Apple-interchange-newline" /&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;

Continuous-time general link transmission model with simplified fanning, Part II: Event-based algorithm for networks

In this paper a novel solution algorithm is proposed for solving general first order dynamic network loading (DNL) problems in general transport networks. This solution algorithm supports any smooth non-linear two regime concave fundamental diagram and adopts a simplified fanning scheme. It is termed eGLTM (event-based General Link Transmission Model) and is based on a continuous-time formulation of the kinematic wave model that adapts shockwave theory to simplify expansion fans. As the name suggests eGLTM is a generalisation of eLTM, which is a special case that solves the simplified first order model assuming a triangular fundamental diagram. We analyse the impact of modelling delay in the hypocritical branch of the fundamental diagram to assess the differences between the two models. In addition, we propose an additional stream of mixture events to propagate multi-commodity flow in event based macroscopic models, which makes both eLTM and eGLTM suitable for dynamic traffic assignment (DTA) applications. The proposed solution scheme can yield exact solutions as well as approximate solutions at a significantly lesser cost. The efficiency of the model is demonstrated in a number of case studies. Furthermore, different settings for our simplified fanning scheme are investigated as well as an extensive analysis on the effect of including route choice on the algorithms computational cost. Finally, a large scale case study is conducted to investigate the suitability of our newly proposed model in a practical context and assess its efficiency. In this study comparisons between eLTM and eGLTM are included to demonstrate the impact of aforementioned generalisation as well as the multi-commodity extension that is proposed.

Continuous-time general link transmission model with simplified fanning, Part I: Theory and link model formulation

The kinematic wave theory is widely used to simulate traffic flows on road segments. Link transmission models are methods to find a solution to the kinematic wave model, however, their computational efficiency heavily relies on the shape of the fundamental diagram that is used as input. Despite the limitations and drawbacks of triangular and piecewise linear fundamental diagrams, they remain popular because they result in highly efficient algorithms. Using smooth nonlinear branches is often preferred in terms of realism and other desirable properties, but this comes at a significantly higher computational cost and requires time discretization to find an approximate solution. In this paper we consider a nonlinear fundamental diagram as input and propose on-the-fly multi-step linearization techniques to simplify expansion fans. This leads to two simplified link transmission models that can be solved exactly in continuous time under the assumption of piecewise stationary travel demand. One of the models simplifies to shockwave theory in case of a single step. We show that embedding shockwave theory in the link transmission model allows for finding an exact solution in continuous time and we discuss the potential for the design of efficient event-based algorithms for general networks.

Automatic identification of near-stationary traffic states based on the PELT changepoint detection

The existence of stationary states during peak periods has been an underlying assumption of many studies on analysis, operations, control, and management of transportation networks. In Cassidy (1998), a method was proposed to manually identify near-stationary states by visually inspecting transformed curves of cumulative total vehicle counts and occupancies. Such near-stationary states are important for calibrating fundamental diagrams, identifying active bottlenecks and incidents, and quantifying capacity drop magnitudes. To the best of our knowledge, however, there lacks an automatic method that can be applied to efficiently identify near-stationary states from a large amount of data.In this study, we attempt to fill this gap. We start with definitions of steady, stationary, and equilibrium states and discuss their relations. Then we present a novel four-step method for automatically identifying near-stationary states from raw loop-detector data: first, the raw data are pre-processed to obtain healthy datasets, fill in missing values, and normalize averaged vehicle counts and occupancies to the same scale; second, daily time series are partitioned into multiple candidate intervals based on the pruned exact linear time (PELT) changepoint detection method; third, the characteristics of the candidate intervals are calculated; and finally, near-stationary states are selected based on modified Cassidy’s gap and duration criteria. We further close the loop by presenting an algorithm to automatically determine the penalty threshold in the second step and the gap threshold in fourth step to ensure the quantity as well as the quality of identified near-stationary states. In a case study, we apply the proposed method to identify near-stationary states from a large set of 30-s raw loop-detector data at a freeway mainline station. We verify the validity of identified near-stationary states both directly and indirectly. The results show that the identified near-stationary states are valid with high quality and the calibrated triangular fundamental diagram is well-fitted and physically meaningful. We finally conclude by discussing some future improvements and potential applications.

Prediction the concentration of graphite direct exfoliation by liquid solution with solubility parameters map

This study is to discuss solvent selection with graphene dispersion concentration of directly exfoliation graphite. That limiting boundaries of fractional cohesion parameters will be draw on the triangular diagram to prediction and estimate. It is based on the literature of data and check with experimental or other literature results, include organic solution, aqueous solution and ionic liquid. In this work, we found that estimated the graphene dispersion concentration by distance (Ra) of Hansen solubility parameters (HSP) between graphene and solvent, the lower Ra; the higher concentration, some case the lower Ra; the lower dispersion concentration (such as acetone). It is compatible with the graphene dispersion concentration on the Hansen space or Triangular fractional cohesion parameters dispersion diagram. From Triangular fractional cohesion parameters dispersion diagram, 2D maps are more convenient for researchers than 3D maps of Hansen space and quickly to find the appropriate combination of solvents for different application.

Petrographic Studies of the Vihowa Formation, Sulaiman Range, Pakistan: Implications for Provenance

The Vihowa Formation of late to early Miocene is investigated for mineral composition and petrographic characteristics to understand the provenance, diagenesis and depositional environments. Ten representative sandstone samples were collected from various lithological units for petrographic studies. Petrographic results show that the quartz is a major constituent; while the accessory minerals are chlorite, chamosite, palagonite, sphalerite, staurolite, aragonite, hypersthene, glaucophane, monazite, kyanite, epidote, olivine, rutile, ilmenite, hematite, magnetite, zircon, tourmaline and garnet. The tourmaline and rutile showing an igneous source however, the presence of epidote, staurolite and garnet expresses a metamorphic source for studied sandstones. The sandstone is medium to coarse grained having grains dominantly from the meta-sedimentary rocks whereas minor amount of grains from igneous rocks is also observed. Monocrystalline quartz is present in sands derived either from gneiss or granitic rocks, but polycrystalline quartz are from slate and schist. The inclusion of mica and garnet within quartz is observed which indicates a metamorphic source. On the QFL triangular diagram the sandstone of Vihowa Formation is mainly sub-lithic arenite and partly quartz arenite. The Qm-P-K plots indicate that feldspar and quartz are from granitic rocks along with small amount from metamorphic and volcanic rocks. The provenance of sandstone indicates that sediments were mostly deposited by transitional recycled orogeny and mixed magmatic subduction complex.

Simulation of Separation of a Racemic Mixture of Ibuprofen by Supercritical Fluid Chromatography in Simulated Moving Bed

Separation of a racemic mixture of ibuprofen at a low concentration level by supercritical fluid chromatography in a simulated moving bed (SFC-SMB) is investigated by simulation. The feasibility of ibuprofen enantiomers separation has been experimentally examined in the literature. Our simulation results show that separation of ibuprofen enantiomers is feasible by this method, and R-ibuprofen and S-ibuprofen products with purity of over 99% can be obtained, which agrees with experimental data in the literature. For initial studies, the triangular theory is used to find the operating conditions. This simulation shows that the application of the triangular diagram is valuable in cases where none of the operating conditions is available. The operating point conditions, such as streams flow rates and switching time, are obtained with this method. Also, the effect of the location of the selected operating points in the triangular diagram on operating conditions, purity, and concentration of the products are investigated. In triangle theory, the optimal operating point should be near the vertex of the triangle diagram with a safety margin, to obtain products with high purity. The simulation also confirms that selecting the operating point away from the vertex of the triangular diagram will lead to diluted products.

Kinematic wave models of sag and tunnel bottlenecks

Sags and tunnels are critical traffic bottlenecks, as they can cause capacity reduction, capacity drop, and extreme low acceleration rates when vehicles accelerate away from the upstream queue. In this paper, we present a behavioral kinematic wave model to explain the three bottleneck effects of sags and tunnels. Assuming increasing time gaps, we derive location-dependent triangular fundamental diagrams to explain the capacity reduction effect; with a bounded acceleration constraint on the stationary states inside the capacity reduction zone, we demonstrate the occurrence of capacity drop and derive a formula to calculate the dropped capacity from the fundamental diagram, road geometry, and acceleration process; from the structure of continuous standing waves we verify the low acceleration rate out of the upstream queue. We also present a simplified phenomenological model of capacity drop at sag/tunnel bottlenecks and two Cell Transmission Models for numerical simulations. With four stationary trajectories at the Kobotoke tunnel in Japan, we calibrate and validate the behavioral model and find that the theoretical predictions match the observations very well. This study can help to develop better design and control strategies to improve the performance of a sag or tunnel bottleneck.

Major Ionic Features and Their Possible Controls in the Water of the Niyang River Basin

In order to study the hydrochemical characteristics and their possible controls for the chemical composition of the water from the Niyang River Basin, 30 samples were collected from wells, springs, and the river in 2014 and major ion concentrations were measured. Descriptive statistics, the Gibbs figure, an ion ratio, and Piper triangular diagrams were used to investigate the hydrochemical characteristics, influencing factors, and hydrochemical evolution of the water in the basin. The results showed that the major cations in this water were Ca2+ and Mg2+, accounting for more than 84% of cations and the main anions were HCO3- and SO42-, accounting for more than 97% of anions The hydrochemical typology of the water is HCO3·SO4(SO4·HCO3)-Ca·Mg (Mg·Ca). The total dissolved solids (TDS) in the water ranges from 79.11 to 290.48 mg·L-1 with an average of 165.21 mg·L-1. The chemical composition of water samples is located to the left of the Gibbs model, which indicates that the chemical process of Niyang River Basin are controlled by rock weathering. According to the principal component analysis and correlation analysis, the hydrochemical composition is controlled by silicate weathering, however, carbonate weathering also plays an important role.

A combination of pressure-swing and extractive distillation for separating complex binary azeotropic system

Methyl acetate/methanol/water mixture forms more than one different azeotrope, whereas its triangular diagram presents a distillation boundary at atmospheric pressure. The two different simulation processes of the double column pressure-swing with extractive distillation (DCPSED) and triple column pressure-swing with extractive distillation (TCPSED) were proposed to separate the complex ternary system. Furthermore, the heat integration and mechanical vapor compression (MVR) heat pump distillations were also tested (through simulation) to separate the complex ternary system to save energy. The feasibility of the processes was confirmed using vapor-liquid equilibrium curve, while rigorous steady-state simulations were implemented using Aspen Plus (version 7.1). With the goal of achieving minimum energy consumption and minimum total annual cost (TAC), the purities of methyl acetate, methanol and water were used as the constraint variables. The results show that water was a better solvent for this separation system. Compared with the TCPSED process, the energy consumption and TAC for DCPSED process could be reduced by 44.83%, and 47.74%, respectively. Compared with the DCPSED and DCPSED with heat integration processes, DCPSED with MVR process could reduce the energy consumption by 73.34% and 59.52%, while TAC was decreased by 37.64% and 11.77%, respectively. The simulation results indicated that DCPSED with MVR process has great advantage over other processes used to separate methyl acetate/methanol/water ternary mixture.

Equation-Oriented Mixed Micellization Modeling of a Subregular Ternary Surfactant System with Potential Medical Applications

The aqueous tricomponent surfactant mixture dodecyltrimethylammonium bromide (DTAB), sodium 10-undecenoate (SUD), and sodium dodecanoate (SDD) has been studied over the complete triangular diagram. This system is highly nonideal and has a coacervate domain. The mixtures do not precipitate in any proportion. There is a wide region of the phase diagram with positive deviations of the critical micelle concentration (CMC). The thermodynamic analysis has been done with the recently developed equation-oriented mixed micellization model (EOMMM) since the widely employed multicomponent regular solution theory (MRST) failed to represent this subregular ternary surfactant system. The advantages of the EOMMM over the MRST are discussed. The biocide properties of DTAB and SUD against microorganisms, the high CMCs that ensure high concentrations of biologically active monomers, and the possibility of having a system that remains liquid in any proportion make the present system attractive for the design of bactericide and antifungal preparations for the medicine, food, and cosmetic industries.