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1

Repowering strategies: Analysis of gas turbine integration with steam cycle for enhanced power plant performance

Badyda Krzysztof, Harutyunyan Artur, Wołowicz Marcin

Archives of Thermodynamics

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2024

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Vol. 45, no 2

99--106

EN

In this paper, various repowering methods commonly employed in practice today are discussed. A particular emphasis is put on the hot wind-box repowering method, which is examined in greater detail. This method stands out for its simpler solution and lower investment costs compared to other repowering methods. Most research and analyses on repowering, taking into account the ecological problems and the possibilities of repowering existing old steam cycle power plants, have focused on the effect of repowering on thermodynamic parameters and emission reduction․ However, there are still many important questions that remain open and unexplored when it comes to analyze the selection of the right technology of the repowering and the right gas turbine for such a combined cycle power plant. For that purpose, based on the oxygen fraction in the gas turbine exhaust gases, nine different gas turbine models were tested for a 200 MW steam cycle power plant model. Calculations were carried out using the GateCycle modelling program. As a result of investigations, a GE Energy Oil & Gas MS9001E SC (GTW 2009 ‒ with 123 MW power) gas turbine was selected as the best one for such a combination, in which case the increase of total net power output by 97.69% and the improvement of efficiency by 6.67% were registered, compared to the results before repowering, while carbon dioxide emissions were decreased by 0.29% per megawatt electrical power generated. The conducted research underscores the importance of selecting the right gas turbine for such a gas-steam system.

2

Analysis of Standard Methods for Determining the Properties of Explosive Materials in Ukraine

Zakusylo Roman, Zakusylo Daryna, Sałaciński Tomasz

Central European Journal of Energetic Materials

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2023

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Vol. 20, no. 1

75--91

EN

Standardized methods for determining the basic properties of energysaturated materials in Ukraine are considered. The optimal directions for the use and development of explosives testing methodology in Ukraine are presented. All of the methods considered can be applied under certain conditions, depending on the initial requirements for the test explosive.

3

Termodynamiczne podstawy procesu usuwania arsenu z miedzi

Kucharski Marian

Rudy i Metale Nieżelazne Recykling

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2020

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R. 65, nr 7-8

3--11

PL

W pracy dokonano obliczeń aktywności arsenu w ciekłych stopach Cu-As w oparciu o dane eksperymentalne różnych autorów. Do obliczeń użyto zależności ciśnienia par arsenu nad arsenem w stanie stałym, którą wyznaczono wykorzystując dane literaturowe: [wzór matematyczny] ciśnienia parcjalne cząstek arsenu, które współistnieją w fazie gazowej. Arsen w stanie stałym był wykorzystywany jako źródło arsenu w fazie gazowej nad badanymi stopami Cu-As. W wysokich temperaturach, ciśnienie arsenu nad czystym ciekłym arsenem określano z zależności ustalonej w oparciu o dane literaturowe: [wzór matematyczny]. Obliczone za pomocą tych relacji współczynniki aktywności arsenu w miedzi różnią się od wartości podawanych przez autorów wykorzystanych prac. W oparciu o uzyskane, wyniki określono graniczne wartości współczynnika aktywności arsenu, które są większe od wartości podawanych w literaturze, co współgra ze stosunkowo niskimi wartościami (co do bezwzględnej wartości) entalpii mieszania roztworów Cu-As [33]. Proces usuwania arsenu z miedzi reprezentuje reakcja: [wzór matematyczny]. W pracy określoną stałą równowagi tej reakcji, która jest równa: [wzór matematyczny]. Stanem odniesienia dla aktywności tlenu w miedzi ( ) jest roztwór nieskończenie rozcieńczony [17]. Stała równowagi i graniczna wartość współczynnika aktywności arsenu w miedzi została wykorzystana do symulacji procesu rafinacji ogniowej w temperaturze 1423 K.

EN

In this work, arsenic activity in liquid Cu-As alloys was determined with use of experimental data of various authors. The dependence of arsenic pressure over pure solid arsenic was used for these calculations, which was determined using the literature data: [mathematical formula] where: partial pressure of arsenic particles that coexist in the gas phase. Solid arsenic was used as a source of arsenic in the gas phase over the investigated Cu-As alloys. At high temperatures, the arsenic pressure over pure liquid arsenic was determined from a relationship established with use of the literature data: [mathematical formula]. The arsenic activity coefficients in Cu-As mixtures were calculated with employment of the above relations, and obtained values differ from the literature data. The obtained results enable us to determine the limiting values of the arsenic activity coefficient ( ). The estimated values are higher than the corresponded data reported in the literature, which is in tune with relatively low values (in absolute scale) of heats of mixing in the liquid Cu-As system [33]. The process of arsenic removal from copper was represented by the reaction: [mathematical formula]. In addition, the equilibrium constant of this reaction was determined, which is expressed by the relation: The reference state for oxygen activity in copper ( ) is an infinitely diluted solution for [17]. The equilibrium constant and limiting value of the arsenic activity coefficient in Cu-As alloys were used to simulate the fire refining process at 1423 K.

4

Termodynamiczna analiza ciekłych roztworów Cu-S-O

Kucharski Marian

Rudy i Metale Nieżelazne Recykling

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2019

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R. 64, nr 6

8--16

PL

W pracy dokonano analizy właściwości termodynamicznych stopów Cu-S-O w oparciu o dane literaturowe. Większość dostępnych danych literaturowych może być obarczone błędami spowodowanymi tym, że próbki stopów były pobierane przez zasysanie do rurek kwarcowych, a następnie chłodzone w wodzie lub w strumieniu azotu. Podczas krzepnięcia tych stopów może wydzielać się SO2.

EN

The paper analyzes thermodynamic properties of Cu-S-O alloys based on the literature data. Most of available literature data may be affected by errors due to the fact that alloy samples were taken by sucking into silica tubes and then cooled in water or under a stream of nitrogen. During the solidification of these alloys, SO2 may be formed.

5

Termodynamiczna analiza ciekłych roztworów Cu-O

Kucharski M.

Rudy i Metale Nieżelazne Recykling

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2018

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R. 63, nr 11

9--13

PL

Artykuł prezentuje nowy sposób opisu właściwości termodynamicznych ciekłych roztworów Cu-O, który opiera się na przyjęciu stanu odniesienia dla tlenu rozpuszczonego w miedzi - roztworu nieskończenie rozcieńczonego (γ[O]=1 dla x[O]=0). Dla tak wybranego stanu odniesienia wyznaczono: 1. Stałą równowagi reakcji rozpuszczania się tlenu w ciekłej miedzi. 2. Energię swobodną reakcji rozpuszczania się tlenu w ciekłej miedzi. 3. Potencjał chemiczny tlenu w miedzi dla roztworu niekończenie rozcieńczonego. 4. Niezależny od temperatury współczynnik aktywności tlenu w ciekłej miedzi.

EN

This study presents a new method of thermodynamic properties description of liquid Cu-O solutions which is based on selection of infinite dilute solution as the reference state for oxygen dissolved in copper (γ[O]=1 for x[O]=0). For this reference state the following relationships were established: 1. The equilibrium constant for the reaction of oxygen dissolution in liquid copper 0,5O2(g)=[O]Cu - Eq.8. 2. The Gibbs energy of reaction of oxygen dissolution in liquid copper 0.5O2(g)=[O]Cu- Eq.9. 3. The chemical potential of the oxygen in infinite dilute solution (Eq. 11). 4. The activity coefficient of the oxygen dissolved in liquid copper (Eq. 13).

6

Thermodynamic Properties of Cu-S Solutions

Kucharski M.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 4

1815--1820

EN

A new method for description of thermodynamic properties of Cu-S mixtures is put forward. The basic feature of this method is the assumption that the activity coefficient of sulphur dissolved in liquid copper is equal to 1 for infinite dilute solution (y[S] = 1 for x[S] = 0). In consequence the following relationships were established: 1. The equilibrium constant for the reaction of sulphur dissolution in liquid copper (0.5S2 (g) = [S] Cu ): [wzór]. 2. Non-temperature dependence of the activity coefficient of sulphur dissolved in the copper-reach liquid (Liquid I): lnγ[S] =-18.25 · x[S] . 3. The chemical potential of the sulphur dissolved in copper in infinite dilute solution: [wzór]. 4. Non-temperature dependence of the activity of sulphur in Cu-S sulphur-rich liquid (Liquid II) – Fig. 6. 5. Non-temperature dependence of the activity of copper in Cu-S sulphur-rich liquid (Liquid II) – Fig. 7. 6. The equilibrium constant for the reaction of sulphur removal from liquid copper ([S] Cu + 2[O] Cu = SO2 (g)): [wzór].

7

Wstępna ocena stałych heterogenicznych paliw rakietowych na bazie azotanów(V), o obniżonej zawartości chlorowodoru w produktach spalania

Bogusz R., Magnuszewska P., Florczak B., Szemlińska N., Maranda A.

Przemysł Chemiczny

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2017

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T. 96, nr 12

2481--2485

PL

Przedstawiono wstępną ocenę zastosowania soli kwasu azotowego(V) w stałych heterogenicznych paliwach rakietowych (SHPR) o obniżonej zawartości HCl w produktach spalania, opartych na układzie HTPB/NA (polibutadien zakończony grupami hydroksylowymi/chloran(VII) amonu). Wykorzystując program ICT-Code, określono teoretycznie właściwości termochemiczne i termodynamiczne proponowanych paliw, takie jak izochoryczne ciepło spalania (Q), impuls właściwy (Isp) oraz skład produktów spalania w komorze i dyszy silnika rakietowego. Wybrano 5 kompozycji SHPR o zawartości 0.3-1% HCl w produktach spalania i wykonano je w skali laboratoryjnej. Uzyskane paliwa spalano w mikrosilniku rakietowym w celu wyznaczenia właściwości balistycznych. Metodami eksperymentalnymi wyznaczono właściwości reologiczne i takie parametry, jak izochoryczne ciepło spalania, temperatura rozkładu oraz wrażliwość na bodźce mechaniczne.

EN

Nine solid rocket propellants consisting of a com. rubber binder, NH₄NO₃, NaNO₃, KNO₃, Al/Mg and Al powders, dimeryl diisocyanate and dioctyl adipate were characterized by thermodynamic calculations. Three of the propellants were tested exptl. for friction and impact sensitivities, hardness, calorific value, decompn. temp., and combustion time. The emission of HCl in the combustion product was decreased down to below 1%.

8

Thermodynamic study of phase equilibrium of superionic alloys of Ag3SBr1-xClx system in the concentration range 0.0–0.4 and temperature range 370–395 K

Moroz M. V., Prokhorenko M. V., Prokhorenko S. V., Reshetnyak O.V.

Archives of Thermodynamics

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2017

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Vol. 38, no. 1

27--38

EN

Thermodynamic assessment of the phase stability of the solid solutions of superionic alloys of the Ag3SBr1-xClx (I) system in the concentration range 0 ≤ x ≤ 0.4 and temperature range 370–395 K was performed. Partial functions of silver in the alloys of solid solution were used as the thermodynamic parameters. The values of partial thermodynamic functions were obtained with the use of the electromotive force method. Potential-forming processes were performed in electrochemical cells. Linear dependence of the electromotive force of cells on temperature was used to calculate the partial thermodynamic functions of silver in the alloys. The serpentine-like shape of the thermodynamic functions in the concentration range 0–4 is an evidence of the metastable state of solid solution. The equilibrium phase state of the alloys is predicted to feature the formation of the intermediate phase Ag3SBr0.76Cl0.24, and the solubility gap of the solid solution ranges of Ag3SBr0.76Cl0.24 and Ag3SBr.

9

Aspekty termodynamiczne zatłaczania dwutlenku węgla w procesach intensyfikacji wydobycia ropy naftowej i gazu ziemnego (EOR/EGR)

Habera Ł.

Prace Naukowe Instytutu Nafty i Gazu

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2016

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nr 210

1--169

PL

W monografii przedstawiono metody laboratoryjne, korelacje empiryczne i rozwiązania analityczne wyznaczania minimalnego ciśnienia mieszania (MMP, minimum miscibility pressure), jako kluczowego parametru w projektowaniu procesu podziemnego zatłaczania CO2 ukierunkowanego na zwiększenie odzysku płynu złożowego. W pracy przybliżono fizyczną naturę dwutlenku węgla (CO2), podkreślono rolę mieszalnego charakteru wypierania ropy naftowej oraz wskazano metody wyznaczania minimalnego ciśnienia mieszania. Przedstawiono mechanizmy, które powodują, że sczerpanie węglowodorów w procesach intensyfikujących wydobycie osiąga wysoki poziom. Termofizyczne własności ropy i zatłaczanego dwutlenku węgla (CO2) determinują istnienie złożonych procesów mieszania płynów zachodzących w wyniku występowania przejść fazowych, którym towarzyszy migracja składników układu. Scharakteryzowano mechanizm parowania, kondensacji i mechanizm złożony, łączący cechy obu wcześniej wymienionych. Rozważania na temat podziemnego zachowania CO2 oparto na badaniach laboratoryjnych przeprowadzonych przez autora rozprawy na fizycznym modelu złoża typu slim tube. Kluczową część pracy stanowi autorski model analityczny do wyznaczania współczynnika sczerpania złoża RF oraz minimalnego ciśnienia mieszania układu ropa naftowa–CO2. Proponowany model oparty jest na metodzie wielokrotnego kontaktu płynów (zatłaczanego i wypieranego) w koncepcyjnych komorach mieszania, symulując przebieg testu laboratoryjnego typu slim tube. Sercem modelu jest moduł obliczeń termodynamicznej równowagi fazowej z wykorzystaniem, jako przykładowego, równania stanu Soave'a–Redlicha–Kwonga (SRK).

EN

This monograph presents empiric correlations as well as laboratory and analytical methods to predict Minimum Miscibility Pressure, which is a crucial parameter of Enhanced Oil and Gas Recovery process. Moreover, the vaporizing, condensing and combined gas drive were demonstrated as displacment mechanisms that occur during the CO2–EOR process. The description of CO2–Oil interaction was based on laboratory Slim Tube tests conducted by the author. The focal point of the thesis is the analytical model designed to determine minimum miscibility pressure (MMP) and recovery factor (RF). The model is based on the multiple contact of CO2 as an injected fluid and oil at virtual mixing cells. In the aforementioned model only thermodynamic relation describe the system and Soave–Redlich–Kwong equation of state was used, as a paradigm in order to perform numerous flash calculations.

10

Predictive study of structural, electronic, magnetic and thermodynamic properties of XFeO3 (X = Ag, Zr and Ru) multiferroic materials in cubic perovskite structure: first-principles calculations

Moulay N., Ameri M., Azaz Y., Zenati A., Al-Douri Y., Ameri I.

Materials Science Poland

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2015

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Vol. 33, No. 2

402--413

EN

The full potential linear-muffin-tin-orbital method within the spin local density approximation has been used to study the structural, electronic, magnetic and thermodynamic properties of three multiferroic compounds of XFeO3 type. Large values of bulk modulus for these compounds have been obtained, which demonstrates their hardness. The calculated total and partial density of states of these compounds shows a complex of strong hybridized 3d and 4d states at Fermi level. The two degenerate levels e(g) and t(2g) clearly demonstrate the origin of this complex. We have also investigated the effect of pressure, from 0 GPa to 55 GPa, on the magnetic moment per atom and the exchange of magnetic energy between the ferromagnetic and antiferromagnetic states. For more detailed knowledge, we have calculated the thermodynamic properties, and determined heat capacity, Debye temperature, bulk modulus and enthropy at different temperatures and pressures for the three multiferroic compounds. This is the first predictive calculation of all these properties.

11

Investigations of structural, elastic, electronic and thermodynamic properties of lutetium filled skutterudite LuFe4P12 under pressure effect: FP-LMTO method

Boudia K., Ameri M., Al-Douri Y., Ameri I., Bouafia H.

Materials Science Poland

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2015

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Vol. 33, No. 4

867--878

EN

Structural, elastic, electronic and thermodynamic properties of ternary cubic filled skutterudite compound were calculated. We have computed the elastic modulus and its pressure dependence. From the elastic parameter behavior, it is inferred that this compound is elastically stable and ductile in nature. Through the quasi-harmonic Debye model, in which phononic effects are considered, the effect of pressure P (0 to 50 GPa) and temperature T (0 to 3000 degrees C) on the lattice constant, elastic parameters, bulk modulus B, heat capacity, thermal expansion coefficient alpha, internal energy U, entropy S, Debye temperature theta(D), Helmholtz free energy A, and Gibbs free energy G are investigated.

12

FP-LAPW investigation of mechanical and thermodynamic properties of Na2X (X = S and Se) under pressure and temperature effects

Bidai K., Ameri M., Bensaid D, Moulay N. E., Al-Douri Y., Ameri I.

Materials Science Poland

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2015

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Vol. 33, No. 3

649--659

EN

Structural, elastic and thermodynamic properties of sodium chalcogenides (Na2X, X = S, Se) have been calculated using FP-APW+lo method. The ground state lattice parameter, bulk moduli have been obtained. The Zener anisotropy factor, Poisson’s ratio, shear modulus, Young’s modulus, have also been calculated. The calculated structural and elastic constants are in good agreement with the available data. We also determined the thermodynamic properties, such as heat capacities Cv and Cp, thermal expansion α, entropy S, and Debye temperature ΘD, at various pressures and temperatures for Na2X compounds. The elastic constants under high pressure and temperature are also calculated and elaborated.

13

Ab-initio study of structural, elastic, electronic and thermodynamic properties of BaxSr1-xS ternary alloys

Chelli S., Touam S., Hamioud L., Meradji H., Ghemid S., Hassan F. E.

Materials Science Poland

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2015

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Vol. 33, No. 4

879--886

EN

The structural, elastic, electronic and thermodynamic properties of BaxSr1-xS ternary alloys have been investigated using the full-potential (linearized) augmented plane wave method. The ground state properties, such as lattice constant, bulk modulus and elastic constants, are in good agreement with numerous experimental and theoretical data. The dependence of the lattice parameters, bulk modulus and band gap on the composition x was analyzed. Deviation of the lattice constant from Vegard's law and the bulk modulus from linear concentration dependence (LCD) was observed. The microscopic origins of the gap bowing were explained by using the approach of Zunger et al. The thermodynamic stability of BaxSr1-xS alloy was investigated by calculating the excess enthalpy of mixing, Delta H-m and the calculated phase diagram showed a broad miscibility gap with a critical temperature.

14

FP-LMTO study of structural, electronic, thermodynamic and optical properties of Mg x Cd1−x Se alloys

Bensaid D, Ameri M, El Hanani M D, Azaz Y, Bendouma D, Al-Douri Y, Ameri I

Materials Science Poland

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2014

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Vol. 32, No. 4

719--728

EN

Structural, electronic and optical properties of MgxCd1−xSe (0 6 x 6 1) are calculated for the first time using density functional theory. Our results show that these properties are strongly dependent on molar fraction of particular components – x. The bond between Cd and Se is partially covalent and the covalent nature of the bond decreases as the concentration of Mg increases from 0 % to 100 %. It is found that MgxCd1−xSe has a direct band gap in the entire range of x and the band gap of the alloy increases from 0.43 to 2.46 eV with the increase in Mg concentration. Frequency dependent dielectric constants ε1(ω),ε2(ω) refractive index n(ω) are also calculated and discussed in detail. The peak value of refractive indices shifts to higher energy regions with the increase in Mg. The larger value of the extraordinary refractive index confirms that the material is a positive birefringence crystal. The present comprehensive theoretical study of the optoelectronic properties of the material predicts that it can be effectively used in optoelectronic applications in the wide range of spectra: IR, visible and UV. In addition, we have also predicted the heat capacities (CV ), the entropy (S), the internal energy (U) and the Helmholtz free energy (F) of MgxCd1−xSe ternary alloys.

15

New Features of Entall Database: Comparison of Experimental and Model Formation Enthalpies

Dębski A., Dębski R., Gąsior W.

Archives of Metallurgy and Materials

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2014

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Vol. 59, iss. 4

1337--1343

EN

This paper presents a new version of the Entall database of the thermodynamic properties of metals and their alloys. The changes are related to the thermodynamic data of new binary and ternary systems as well as the integration of the database with an application for the modeling of the formation enthalpies of intermetallic phases with the use of the Miedema model. Using this tool, calculations of the enthalpies of formation of 38 intermetallic phases from 12 binary systems were performed and a comparative analysis conducted. The results of the analysis clearly showed a weak correlation between the model and experimental data. To improve this correlation, an intermediate method of proportional change was proposed, on the basis of the measurement of the enthalpy of formation for one of the phases. The values for the other phases obtained from this indirect method should not deviate much from the experimental ones provided that before the measurements (dissolving or pulping) or after them (direct synthesis), the phase being examined should undergo structural tests, in order to confirm its dominating amount in the samples.

PL

W pracy przedstawiona została nowa wersja bazy właściwośsci termodynamicznych metali i stopów Entall. Modyfikacja dotyczyła z jednej strony danych termodynamicznych nowych układów dwu i trójskładnikowych a z drugiej zaadaptowania do niej opracowanego programu (kalkulatora) do modelowania entalpii tworzenia faz międzymetalicznych modelem Miedemy. Korzystając z tego nowego narzędzia wykonane zostały obliczenia entalpii tworzenia dla 38 faz międzymetalicznych z 12 układów dwuskładnikowych oraz przeprowadzona została analiza porównawcza. Wyniki analizy pokazały jednoznacznie słaba korelacje między danymi modelowymi i doświadczalnymi. Dla poprawienia tej korelacji zaproponowana została pośrednia metoda proporcjonalnej zmiany w oparciu o pomiar entalpii tworzenia dla jednej z faz. Uzyskane z tej pośredniej metody wartości dla innych faz powinny niewiele odbiegąc od eksperymentalnych przy spełnieniu warunku, że faza dla której wykonywane były badania została przed pomiarami (rozpuszczanie lub roztwarzanie) lub po nich (bezpośrednia synteza) poddana badaniom strukturalnym, w celu potwierdzenia jej dominującej ilości w próbkach.

16

Współczynniki aktywności w rozcieńczeniu nieskończenie wielkim jako podstawowa informacja do opisu termodynamicznych i ekstrakcyjnych właściwości cieczy jonowych

Domańska-Żelazna U.

Przemysł Chemiczny

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2013

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T. 92, nr 9

1589-1593

PL

Przedstawiono przegląd literaturowy z ostatnich lat, dotyczący możliwości wykorzystania cieczy jonowych w ekstrakcji i rozdzielaniu na podstawie badań współczynników aktywności w rozcieńczeniu nieskończenie wielkim (γ∞ 12).

EN

A review, with 45 refs., of activity coeffs. at infinite dilution of ionic liqs. used for sepn. of arom. and aliph. hydrocarbons or S compds. and aliph. hydrocarbons. The partial excess molar Gibbs energies, gas-liq. partition coeffs. and the Hildebrand soly. parameters were taken into consideration.

17

Theoretical Studies of High-nitrogen-containing Energetic Compounds Based on the s-Tetrazine Unit

Man T. T., Wang K., Zhang J.G., Niu X. Q., Zhang T. L.

Central European Journal of Energetic Materials

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2013

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Vol. 10, no. 2

171-189

EN

In order to develop new high-energy-density materials (HEDMs), we have investigated 12 substituted s-tetrazine (TZ) compounds, where s-tetrazine was substituted by amino, amido and related groups. Density functional theory (DFT) was used to predict the optimized geometries, electronic structures, total energy, heats of formation (HOFs) and densities. In addition the detonation properties were evaluated by using the VLW equation of state (EOS). The standard enthalpy of formation, the Gibbs free energy, entropy and equilibrium constants were used to estimate the success of the synthetic substitution reactions, which provided theoretical support for practical work. The bond dissociation energy (BDE) of bond C-R was calculated at each stage of the substitution reaction. The calculated results showed that substitution of amino, amido and their derivatives in the TZ ring enhances the HOF values and is favorable for increasing the thermal stability. The calculated detonation properties indicated that incorporating the above groups into the TZ ring is benefcial for improving the explosive performance. Considering the detonation properties and thermal stability, the 12 derivatives may be regarded as promising candidates as high-energy-density materials (HEDMs).

18

Intermolecular Interactions between TNAZ and H2O: a DFT Study

Oftadeh M., Selahvarzi S., Keshavarz M. H.

Central European Journal of Energetic Materials

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2013

|

Vol. 10, no. 2

289--300

EN

All of the possible TNAZ/H2O complexes (1, 2 and 3), as well as the uncomplexed form, were fully optimized with the density functional method. Complex 3 was the most stable, with the largest corrected intermolecular interaction energy. Charge redistribution mainly occurs on the adjacent N–O...H atoms of the submolecules. Strong hydrogen bonds predominantly contribute to the interaction energies. It is energetically and thermodynamically unfavourable for TNAZ to bind with H2O and to form any stable complexes at room temperature.

19

Dft investigation of a high energy density polynitro compound, 2,2’-Bis(trinitromethyl)-5,5’-azo-1,2,3,4- tetrazole

Lin H., Zhu S. G., Chen P. Y., Li K., Li H. Z., Peng X. H.

Central European Journal of Energetic Materials

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2013

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Vol. 10, no. 3

325--338

EN

A novel polynitro compound, 2,2’-bis(trinitromethyl)-5,5’-azo- 1,2,3,4-tetrazole, was designed and investigated at the DFT-B3LYP/6-31G(d) level. Its properties, such as electronic structure, IR spectrum, heat of formation, thermodynamic properties and crystal structure, were predicted. This compound is most likely to crystallize in the P21 space group, and the corresponding cell parameters are Z = 2, a = 5.46 Å, b = 9.72 Å, c = 14.05 Å, α = 90°, β = 90°, γ = 90°. In addition, the detonation velocity and pressure were also estimated by using the empirical Kamlet-Jacobs equations, and were predicted to be 8.28 km/s and 31.61 GPa respectively. The oxygen balance of this compound is +13.79%, which indicates that it could serve as an oxidizer. Bond dissociation energy calculations show that the C(13)-N(21)O2 and C(14)-N(30)O2 bonds are the locations of thermal decomposition and that this compounds meets the thermal stability requirements as an exploitable explosive. Keywords: polynitro, electronic structure, thermodynamic properties, crystal structure, detonation performance, stability.

20

Thermodynamic properties and phase equilibria in the ternary Cu-Pb-Fe system

Onderka B., Jendrzejczyk-Handzlik D, Fitzner K.

Archives of Metallurgy and Materials

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2013

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Vol. 58, iss. 2

541--548

EN

Using experimental data available in the literature, two binary systems, namely Cu-Pb and Fe-Pb were recalculated. Next, accepting Cu-Fe phase diagram assessment as given by Ansara and Jansson, the ternary Cu-Fe-Pb system was analyzed. Calculated equilibrium lines and thermodynamic functions are compared with existing experimental data. Good agreement was found between the calculated diagram and the experimental results. Having the system optimized, functional dependences of the logarithms of the activity coefficients on temperature and concentrations for Cu, Fe and Pb in the liquid solution are given.

PL

Dwa układy podwójne Cu-Pb oraz Fe-Pb zostały powtórnie zoptymalizowane używając danych eksperymentalnych dostępnych w literaturze. Następnie, akceptując optymalizacje układu Cu-Fe opublikowana przez Ansare i Janssona, poddano analizie trójskładnikowy układ Cu-Pb-Fe. Obliczone linie równowagi faz oraz funkcje termodynamiczne zostały porównane z dostępnymi danymi eksperymentalnymi. Uzyskano dobrą zgodność pomiędzy policzonym układem a danymi eksperymentalnymi. Korzystając z wyników optymalizacji, zostały podane zalezności logarytmu współczynnika aktywności w funkcji temperatury oraz Cu, Fe i Pb w funkcji stężenia dla w roztworze ciekłym.