burning characteristics of ammonium nitrate-based composite propellants supplemented with ammonium...

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Burning Characteristics of Ammonium Nitrate-based CompositePropellants Supplemented with Ammonium Dichromate

Makoto Kohga*, Saeko Nishino

Department of Applied Chemistry, National Defense Academy, Hashirimizu 1-10-20, Yokosuka, Kanagawa 239-8686(Japan)

Received: July 17, 2008; revised version: September 16, 2008

DOI: 10.1002/prep.200800060

Abstract

Ammonium nitrate (AN)-based composite propellants haveattracted much attention, primarily because of the clean burningnature of AN as an oxidizer. However, such propellants havesome disadvantages such as poor ignition and low burning rate.Ammonium dichromate (ADC) is used as a burning catalyst forAN-based propellants; however, the effect of ADC on the burningcharacteristics has yet to be sufficiently delineated. The burningcharacteristics of AN/ADC propellants prepared with variouscontents of AN and ADC have been investigated in this study.The theoretical performance of an AN-based propellant isimproved by the addition of ADC. The increase in the burningrate is enhanced and the pressure deflagration limit (PDL)becomes lower with increasing amount of ADC added. Theincreasing ratio of the burning rate with respect to the amount ofADC is independent of the AN content and the combustionpressure. The optimal amount of ADC for improving the burningcharacteristics has been determined.

Keywords: Ammonium Dichromate, Ammonium Nitrate, BurningCharacteristics, Burning Catalyst, Composite Propellant

1 Introduction

Solid propellants are contained and stored directly in thecombustion chamber of a solid rocket motor, sometimeshermetically sealed in the chamber for long-term storage. Inthe chamber, the propellant reacts to form hot gases, which,in turn, are accelerated and ejected at high velocity througha supersonic nozzle, thereby imparting momentum to therocket motor. Solid rocket motors have been credited withhaving few moving parts. Therefore, they are the propulsionsystems of space launch vehicles, spacecraft, missiles, andother applications

There are various kinds of solid propellants, and a suitablepropellant is selected to meet the requirements of eachparticular rocket motor application. A composite propellant

is a kind of solid propellant in the form of heterogeneouspropellant grains composed of oxidizer crystals and a metalfuel held together in a matrix of a synthetic or plastic binder.Ammonium perchlorate (AP) and hydroxyl-terminatedpolybutadiene (HTPB) are widely used as an oxidizer andbinder, respectively [1]. This is because AP/HTPB-basedpropellants have excellent burning and mechanical charac-teristics. One of the few serious drawbacks of AP-basedpropellants is that the products of combustion, whichinclude HCl, chlorine, and chlorine oxides, cause atmos-pheric pollution.

Recently, ammonium nitrate (AN)-based compositepropellants, i.e., propellants prepared with AN as theoxidizer, have gained popularity, even though there aresome major problems associated with the use of AN-basedpropellants, namely low burning rate, poor ignitability, andlow energy compared with AP-based propellants [1]. This isbecause AN-based propellants are chlorine free with low-hazard and low observable emissions (minimum smoke).Numerous approaches have been adopted to improve theburning characteristics of AN-based propellants, includingthe use of catalysts [2 – 7], the addition of metals [8 – 11], andthe use of energetic binders based on azide polymers [12 –18].

It is known that transition metals/metal compounds arecapable of increasing the burning rate and ignitability of ANpropellants [19]. Ammonium dichromate (ADC) is one ofthe burning catalysts used in AN-based propellants, and theenhancing effect of ADC on the burning rate is great [2, 19,20]. However, the catalytic effect of ADC on the burningrate characteristics of AN-based propellants has yet to besufficiently delineated. In this study, the burning rates ofAN/ADC propellants prepared with various contents of ANand ADC have been investigated and an attempt has beenmade to obtain detailed experimental data on the burningcharacteristics of AN-based propellants supplemented withADC to reveal the effect of this burning catalyst.* e-mail: [email protected]

340 Propellants Explos. Pyrotech. 2009, 34, 340 – 346

� 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

2 Experimental

The AN sample was prepared by grinding special gradeAN (minimum purity 99.0%). ADC was used as a burningcatalyst. The mean particle diameter of the AN was 56 mmand that of the ADC was 23 mm. HTPB was used as a binder.The propellant samples were prepared with less than 80%AN. ADC was added to the propellants in amounts rangingfrom 0.5 to 12%. The amount of ADC added to thepropellant is represented by x.

The thermal decomposition process of the propellants wasmeasured by differential thermal analysis (DTA) andthermogravimetry (TG). The equipment was operatedunder conditions of flowing nitrogen at atmospheric pres-sure. DTA and TG were carried out with a heating rate of20 K min�1.

The size of each propellant strand was 10 mm in diameterand 40 mm in length. The burning behavior was investigatedin a chimney-type strand burner, which was pressurized withnitrogen. Each strand was ignited by applying 12 V to anelectrically heated nichrome wire attached at the top. Eachpropellant strand was combusted in the pressure range from0.5 to 7 MPa. The burning phenomenon of the propellantwas recorded by means of a high-speed video recorder. Theburning rate was measured from the pictures recorded withthe high-speed video recorder. The combustion phenomen-on was recorded with a shutter speed of 125 frames s�1. Theobject was enlarged approximately 10 times and theregression length of the burning surface was measuredwith a resolution of 0.5 mm. The measurement error waswithin 5%.

3 Results and Discussion

3.1 Theoretical Performance of AN/ADC-BasedPropellants

ADC is a burning catalyst for AN-based propellants, aswell as an oxidizer. Therefore, it is also expected that ADCwill affect the burning rate as an oxidizer. Theoreticalcalculation of the propellant performance thus needs to takeinto account the oxidizing effect. However, the catalyticeffect of ADC cannot be taken into account because thiseffect has not been quantitatively determined. Taking ADCto act only as an oxidizer, the theoretical performance of theAN/ADC propellant was calculated using the NASA SP-273 program [21] with a combustion pressure of 7 MPa, anexit pressure of 0.1 MPa, and an initial temperature of298 K.

The influences of x on the adiabatic flame temperatureand the specific impulse of the AN/ADC propellant areshown in Figures 1 and 2, respectively. The adiabatic flametemperature and specific impulse increase with increasing x

at each AN content. The differences in the propellantperformances between the propellant with 60% AN andthat with 70% AN are small; however, the values for thepropellant with 80% AN are much larger than those for the

propellant with 70% AN. It is found that the enhancement inthe propellant performance upon the addition of ADC isgreater at higher AN content.

Figure 3 illustrates the principal combustion productstheoretically evolved from the propellants with 60, 70, and80% AN. Graphite is one of the main combustion productsof the propellant with 60 and 70% AN; however, thepropellant with 80% AN does not generate graphite. For thepropellants with each AN content, the mole fractions of H2

and CO increase distinctly and the fraction of Cr2O3

increases slightly as x is increased. The mole fractions ofthe other combustion products decrease with increasing x.In particular, the mole fraction of graphite produced fromthe propellants with 60 and 70% AN decreases markedly.

From Figure 3, it is evident that for the propellant with80% AN, the carbon atoms of the binder would betheoretically oxidized with the AN alone. For the propel-lants with 60 and 70% AN, the carbon atoms of the binderingredients cannot be completely burned with the oxygenfrom the AN alone and these remain as graphite after the

Figure 1. Theoretical adiabatic flame temperature of AN/ADC-based propellant.

Figure 2. Theoretical specific impulse of AN/ADC-based pro-pellant.

Burning Characteristics of Ammonium Nitrate-based Composite Propellants Supplemented with Ammonium Dichromate 341

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combustion. The amount of graphite is reduced by theaddition of ADC because this also acts as an oxidizer. Theseresults suggest that the burning characteristics will betheoretically improved by the addition of ADC to the AN-based propellant.

ADC is a poisonous material and there are healthconcerns regarding its use in propellant manufacture.ADC burns with the generation of Cr2O3, so it does notremain among the combustion products, as shown inFigure 3. Cr2O3 is a safe and stable chromate compound,which is used as a pigment and colorant. ADC is thus aneffective and practical catalyst for AN-based propellants, aslong as safe conditions are maintained during the manufac-ture and storage of the propellant.

3.2 Thermal Decomposition Behavior

The thermal decomposition characteristics of AN-basedcomposite propellants with and without ADC have beeninvestigated. Figure 4 shows the DTA – TG curves of thepropellants with 60 and 80% AN. These propellants display

two endothermic peaks, at 400 and 442 K. The endothermicpeak at 400 K is due to the phase transformation of AN andthat at 442 K is due to melting. After the melting,exothermic decomposition occurs and a peak is observed.The peak temperature of the exothermic decomposition ofthe propellant with x¼ 12% was approximately 10 K lowerthan that of the corresponding propellant without ADC ateach AN content.

From the TG curves, it can be seen that a rapidconsumption occurs in the region of the exothermicdecomposition of the propellant, between 480 and 550 K.The consumptions of the propellants with 60 and 80% ANare around 60 and 85%, respectively. This region is the maindecomposition of the AN-based propellant. Further, someconsumption of the propellant occurs in the range from 700to 750 K. This mass loss of the propellant with 80% AN issmall, approximately 10%, while that of the propellant with60% AN is approximately 25%. The decomposition ofHTPB occurs between 500 and 800 K [22] and, therefore,HTPB is completely consumed in this temperature range.

Figure 3. Mole fraction of principal combustion products calcu-lated theoretically.

Figure 4. DTA – TG curves of propellants at 60 and 80%AN.

342 M. Kohga, S. Nishino

Propellants Explos. Pyrotech. 2009, 34, 340 – 346 www.pep.wiley-vch.de � 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim


The consumption in the range from 700 to 750 K is due to thedecomposition of the HTPB that was not consumed duringthe main decomposition of the propellant.

For AP-based composite propellants, the exothermicdecomposition peak is remarkably shifted to lower temper-ature by the addition of Fe2O3 as a burning catalyst [23, 24].Carvalheira et al. investigated the thermal decompositionbehavior of AN/HTPB/Fe2O3 composite propellants indetail and reported that the exothermic peak of the DTAcurve is scarcely changed by the addition of Fe2O3 [25]. Theinfluence of x on the peak temperature of the mainexothermic decomposition is shown in Figure 5. The peaktemperature increases with decreasing AN content and isvirtually independent of x at a constant AN content. It wasfound that the thermal decomposition of the AN-basedpropellant was slightly changed by ADC.

3.3 Burning Characteristics

All measurements were checked at least three times ateach pressure, and the burning rate was determined as theaverage of these values. The burning rate was not recorded ifjust one of the three batches of propellants did not ignite orcombust in a stable manner. The unignited conditionimplied that the propellant sample did not burn, or barelyburned, after the ignition event. Self-quenched burningbehavior indicated that the sample burned for some timeafter ignition, before extinguishing. This usually occurredwithin half of the length of the propellant sample in thisstudy.

Figure 6 shows the experimental data and the correspond-ing fitting lines of the burning rate characteristics of the AN-based propellants. The standard deviation of burning ratewas within 0.12. For the propellants with each AN content,the burning rates are seen to increase linearly on thelogarithmic scale. The burning rate decreases as the ANcontent decreases. Propellant combustion tests were carriedout in the pressure range from 0.5 to 7 MPa, as described inSection 2. The burning rate decreases with decreasingpressure and finally the propellant cannot burn at less than acertain pressure. In this experiment, the pressure deflagra-

tion limit (PDL) was determined as the lower limit ofpressure to ignite and deflagrate. The propellant containing80% AN did not burn at 0.5 MPa, indicating that PDL of thispropellant was 1 MPa. The PDL extends from lowerpressure to higher, that is, the combustible pressure rangedecreases with decreasing AN content. A propellant con-taining just 59% AN did not combust in the pressure rangeinvestigated in this study. This result suggests that the lowerlimit of AN content for self-combustion is 60%.

AN/HTPB propellants generated a solid residue in thecombustion chamber after the burning test. Figure 7 shows aphotograph of an AN/HTPB propellant with 80% AN afterquenching by rapid depressurization. The solid residue is onthe burning surface and the shape of the residue is almost thesame as that of the propellant. Theoretically, the propellantwith 80% AN should not generate graphite, as described inSection 3.1. In reality, however, even this propellantproduced a residue after the burning test. This indicatesthat the actual combustion of the propellant is essentiallyinferior to the theoretical combustion.

AN-based propellants containing ADC, i.e., AN/ADCpropellants, with 60, 65, 70, 75, and 80% AN were prepared.Their burning rate characteristics were measured, and theresults are shown in Figure 8. The burning rate can be foundto increase with increasing x. The PDL is decreased by theaddition of ADC and, therefore, the combustible pressurerange is enhanced in the lower pressure region. The PDLvalues are tabulated in Table 1. For the propellants with 80,75, 70, 65, and 60% AN, the PDL values decrease from 1, 2,3, 5, and 6 MPa to 0.5, 0.5, 0.5, 1, and 1 MPa, respectively, bythe addition of ADC.

Furthermore, after the burning test, the propellant con-taining ADC did not leave a solid residue in the combustionchamber like that shown in Figure 7. Of course, small solidresidues would have been generated by the burning, butthese would have been discharged from the combustionchamber with the nitrogen gas. It is thus clear that theburning characteristics of AN-based propellants are im-proved by the addition of ADC.

Figure 5. Exothermic peak temperature as a function of x.

Figure 6. Burning rate characteristics of AN-based propellants.




As mentioned above, the burning rates of AN-basedpropellants decrease with decreasing AN content, but theburning characteristics are improved by the addition ofADC. For the propellants with each AN content, the effectof x on the increase in the burning rate was investigated. Theratio of the burning rate of the AN/ADC propellant to thatof the corresponding AN propellant, R, was calculated fromFigure 8. The relationship between R and x is shown inFigure 9. The value of R increases with increasing x and isvirtually independent of the burning pressure. The increas-ing R ratio versus x changes at around x¼ 5 – 6%, and abovethis value the slope decreases. Thus, it was found that themost effective value of x for increasing the burning rate was6%. The value of R at x¼ 6% is between 1.45 and 1.57.

As mentioned above, ADC acts not only as a burningcatalyst but also as an oxidizer. Thus, the burning character-istics will also be improved by the oxidizing action of ADC.The burning rate of a propellant with an ADC content of80%, without using AN, was measured to investigate thecapacity of ADC to serve as a propellant oxidizer. TheADC-based propellant proved to be incombustible in thepressure range from 0.5 to 7 MPa. An AN-based propellantwith 80% AN burns in the range from 1 to 7 MPa, as shownin Figure 6. This suggests that the capacity of ADC to serveas a propellant oxidizer is inferior to that of AN.

It was found that the most effective value of x forincreasing the burning rate was 6%, as described above,x being the mass ratio of ADC to AN. When both AN andADC served as oxidizers and the value of x was 6%, theoxidizer contents of the AN/ADC propellants at 60, 70, and80% AN were 61.4, 71.2, and 80.92%, respectively. Thisindicates that the oxidizer contents of these propellants areapproximately 1% larger than those of the propellants

without ADC. In spite of these increases in the oxidizercontents of only 1%, the burning rates were increased by1.4 – 1.6 times. The addition of ADC and, furthermore, theburning behavior at lower pressure was remarkably im-proved, as shown in Figure 9 and Table 1. As it is clear fromFigure 6, for the propellants with 60 – 80% AN, the burningrates could not be increased 1.4 times by increasing the ANcontent by just 1%. These results suggest that ADC serves asan effective burning catalyst for AN-based propellantsrather than as an oxidizer.

Cr2O3 catalyzes the oxidation of CH4, CO, H2, and NH3 inan excess of oxygen [26]. As described in Section 3.1,propellants containing ADC generate Cr2O3 as a combus-tion product, and the combustion products of AN-basedpropellants include CH4, CO, H2, and NH3. If Cr2O3 acted as

Figure 7. Photograph of quenched AN/HTPB propellant at 80%AN.

Figure 8. Burning rate characteristics of AN/ADC-based pro-pellants.

Table 1. PDL of propellant.

AN content (%) PDL (MPa)x (%)

0 0.5 1 2 4 6 8 10 12

60 6 5 5 4 4 3 3 2 165 5 3 2 2 2 1 1 1 170 3 2 2 1 1 1 0.5 0.5 0.575 2 2 2 1 1 1 0.5 0.5 0.580 1 1 1 1 1 0.5 0.5 0.5 0.5




a burning catalyst, a great increase in burning rate should beobserved upon the addition of a small quantity of Cr2O3. Theburning rate of an AN-based propellant containing 1%Cr2O3 was therefore measured to investigate the effect ofthis additive on the burning rate. The burning rate of thepropellant containing Cr2O3 was almost the same as that ofthe propellant without Cr2O3. The oxygen balance of apropellant at 94% AN is zero. Therefore, the propellant with80% AN is fuel-rich, i.e., oxygen-deficient. The resultssuggest that Cr2O3 produced by the combustion of ADC didnot accelerate the oxidation of CH4, CO, H2 and NH3, anddid not influence the burning rate of the AN-basedpropellant. The mechanism of action of ADC could not beelucidated in this study.

4 Conclusion

For practical applications of AN-based propellants, it isnecessary to improve their burning characteristics. Theaddition of a burning catalyst is one of the most effectivemethods for improving the burning characteristics of AN-based propellants. In this study, ADC has been used as aburning catalyst, and the burning characteristics of AN/ADC propellants prepared with various AN and ADCcontents have been investigated to reveal the effect of ADC.

The theoretical adiabatic flame temperature and thespecific impulse are both increased upon increasing the

amount of ADC added. ADC hardly affects the thermaldecomposition behavior of AN-based propellants. Theburning characteristics are improved by the addition ofADC. As the mass ratio of ADC to AN, x, is increased, theincrease in the burning rate is enhanced and the PDLbecomes lower. The increasing ratio of the burning rate ofthe AN/ADC propellant to that of the AN propellant versusx changes at around x¼ 5 – 6% and above this value of x theslope decreases. The most effective value of x for increasingthe burning rate was found to be 6%. The propellantscontaining ADC did not leave a solid residue in thecombustion chamber after the burning tests. It has thusbeen found that ADC is an excellent catalyst for AN-basedpropellants.

5 References

[1] G. P. Sutton, Rocket Propulsion Element Sixth Edition, JohnWily & Sons, Inc., New York 1992, p. 420.

[2] Y. Hagihara, T. Ichikawa, H. Shinpo, M. Suzuki, Effects ofChromium and Cobalt Compounds on Burning Rate ofAmmonium Nitrate/Hydroxyl Terminated PolybutadieneComposite Propellants, Kogyo Kayaku (Science and Technol-ogy of Energetic Materials) 1991, 52, 390.

[3] H. Nakamura, M. Akiyoshi, K. Sakata, Y. Hara, Effect ofMetal Complex Catalysis of Tetraaza-(14)-anurene on theThermal Decomposition of Ammonium Nitrate and Ammo-nium Perchlorate, Kayaku Gakkaishi (Science and Technol-ogy of Energetic Materials) 2000, 61, 101.

[4] G. Singh, S. P. Felix, Studies on Energetic Compounds Part36: Evaluation of Transition Metal Salts of NTO as BurningRate Modifiers for HTPB-AN Composite Solid Propellants,Combust. Flame 2003, 135, 145.

[5] M. Q. Brewster, T. A. Sheridan, A. Ishihara, AmmoniumNitrate-Magnesium Propellant Combustion and Heat Trans-fer Mechanisms, J. Propulsion Power 1992, 8, 760.

[6] V. P. Sinditskii, V. Y. Egorshev, A. I. Levshenkov, V. P.Serushkin, Ammonium Nitrate: Combustion Mechanismand the Role of Additives, Propellants, Explos., Pyrotech.2005, 30, 269.

[7] F. N. Tuzun, B. Z. Uysal, The Effect of Ammonium Nitrate,Coarse/Fine Ammonium Nitrate Ratio, Plasticizer, BondingAgent, and Fe2O3 Content on Ballistic and MechanicalProperties of Hydroxyl Terminated Polybutadiene BasedComposite Propellants Containing 20% AP, J. ASTM Int.2005, 2, 233.

[8] T. Kuwahara, N. Shinozaki, Burning Mechanism of Ammo-nium Nitrate/Aluminum Composite Propellants, KogyoKayaku (Science and Technology of Energetic Materials)1992, 53, 131.

[9] B. N. Kondrikov, V. E. Annikov, V. Yu. Egorshev, L. DeLuca,C. Bronzi, Combustion of Ammonium Nitrate-Based Com-positions, Metal-Containing and Water-Impregnated Com-pounds, J. Propul. Power 1999, 15, 763.

[10] H. Murata, Y. Azuma, T. Tohara, M. Simoda, T. Yamaya, K.Hori, T. Saito, The Effect of Magnalium(Mg-Al Alloy) onCombustion Characteristics of Ammonium Nitrate-BasedSolid Propellant, Kayaku Gakkaishi, Sci. Technol. Energ.Mater. 2000, 61, 58.

[11] B. E. Greiner, R. A. Frederick, M. D. Moser, CombustionEffects of C60 Soot in Ammonium Nitrate Propellants, J.Propul. Power 2003, 19, 713.

[12] T. Kazita, T. Saito, T. Yamaya, M. Shimoda, A. Iwama,Ignition Characteristics of GAP/AN/AP-Based Solid Propel-

Figure 9. Influence of x on R (x: mass ratio of ADC).




lants for Low Pollution at Sub-Atmospheric Pressures,Kayaku Gakkaishi, Sci. Technol. Energ. Mater. 1996, 57, 1.

[13] K. Kato, G. Nakasita, Burning Rate Characteristics of GAP/AN Propellant, Kayaku Gakkaishi, Sci. Technol. Energ.Mater. 1995, 56, 130.

[14] Y. Oyumi, E. Kimura, IM Characteristics of GAP/ANComposite Propellants, Kayaku Gakkaishi, Sci. Technol.Energ. Mater. 1996, 57, 9.

[15] M. Takizuka, Combustion Characteristics of GAP BasedComposite Propellants(I) Theoretical Combustion Perfor-mance and Burning Rate, Kayaku Gakkaishi, Sci. Technol.Energ. Mater. 1998, 59, 181.

[16] C. Nakajima, T. Saito, T. Yamaya, M. Shimoda, Effects ofChromium Compounds on PVA-Coated AN and GAPBinder Pyrolysis, and PVA-Coated AN/GAP PropellantCombustion, Fuel 1998, 77, 321.

[17] P. Simioes, L. Pedroso, A. Portugal, I. Plaksin, J. Campos,New Propellant Component, Part 2: Study of a PSAN/DNAM/HTPB Based Formulation, Propellant, Explos., Py-rotech. 2001, 26, 278.

[18] M. D. Judge, P. Lessard, An Advanced GAP/AN/TAGNPropellant, Part 1: Ballistic Properties, Propellant, Explos.,Pyrotech. 2007, 32, 175.

[19] C. Ommen, S. R. Jain, Ammonium Nitrate: A PromisingRocket Propellant Oxidizer, J. Hazard. Mater. 1999, A67, 253.

[20] C. Ommen, S. R. Jain, Phase-Stabilized Ammonium Nitrate-Based Propellants Using Binder with N-N Bonds, J. Propul.Power 2000, 16, 133.

[21] S. Gordon, B. J. McBride, Computer Program for Calculationof Complex Chemical Equilibrium Compositions, RocketPerformance, Incident and Reflected Shocks, and Chapman-Jouguet detonations, NASA SP-273, NASA Lewis ResearchCenter, Wasington, D.C., WA, 1971.

[22] H. Bazaki, N. Kubota, Effect of Binders on the Burning Rateof AP Composite Propellants, Propellants, Explos., Pyrotech.2000, 25, 312.

[23] Y. Ouyumi, N. Tsujikado, T. Ohmura, T. Harada, M. Aboshi,Effects of Iron Compounds on the Decomposition of AP-HTPB Composite Propellants, Kayaku Gakkaishi, Sci. Tech-nol. Energ. Mater. 1981, 42, 144.

[24] M. Kohga, Y. Hagihara, Burning Characteristics of Fuel-RichAP/HTPB Composite Propellant Added with Iron Oxide, Sci.Technol. Energ. Mater. 2003, 64, 110.

[25] P. Carvalheira, G. M. H. J. L. Gadiot, W. P. C. deKlerk, Ther-mal Decomposition of Phase-Stabilized Ammonium Nitrate,Hydroxyl-Terminated Polybutadiene Based Propellants. TheEffect of Iron(III) Oxide Burning-Rate Catalyst, Thermo-chim. Acta 1995, 269/270, 273.

[26] K. Tamura. (Eds.), Pysico-Chemical Theory of Catalysis,Chijinshokan, Tokyo, 1967, p. 164.




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