Investigation of Chemical Processes Involving 

Laser-generated Nanoenergetic Materials 

by Jennifer L. Gottfried 

ARL-MR-0736 February 2010 

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Army Research Laboratory 

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ARL-MR-0736 February 2010 

Investigation of Chemical Processes Involving 

Laser-generated Nanoenergetic Materials 

Jennifer L. Gottfried

Weapons and Materials Research Directorate, ARL 

Approved for public release; distribution unlimited. 
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Investigation of Chemical Processes Involving Laser-generated Nanoenergetic 

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14. ABSTRACT 

The feasibility of a novel approach for studying the chemical reactions between metallic nanoparticles and molecular 

explosives has been demonstrated. This method is based on the production of nanoparticles in a laser-induced plasma and the 

simultaneous observation of the atomic and molecular emission characteristic of the species involved in the intermediate 

chemical reactions of the nanoenergetic material in the plasma. Time-resolved, broadband emission of chemical species 

involved in the reaction of RDX and various metal nanoparticles was observed. The increase in diatomic carbon (C2) and 

aluminum monoxide (AlO) emission with increasing aluminum (Al) content previously observed during an aluminized-RDX 

explosion in a shock tube was confirmed using this method. The time-evolution of species formation in the plasma, the effects 

of laser pulse energy, and the effects of trace metal content on chemical reactions were also studied.

15. SUBJECT TERMS

nanoparticle formation, nanoenergetic materials, laser ablation, plasma chemistry, optical emission 

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Jennifer L. Gottfried 

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iii 

Contents 

List of Figures iv

Acknowledgments v

1. Objective 1

2. Approach 1

3. Results 3

4. Conclusions 7

5. References 9

6. Transitions 11

List of Symbols, Abbreviations, and Acronyms 12

Distribution List 13 
iv 

List of Figures 

Figure 1. Time-resolved double-pulse spectra of RDX on Al in air at various delay times 

(left). While the concentration of atomic species slowly decreases over the first 11 s 

(right), recombination reactions result in higher concentrations of CN, C2, and AlO as the 

plasma cools. ..............................................................................................................................3

Figure 2. Comparison of O and AlO intensities for different laser pulse energies. The O in 

the blank Al spectra is primarily from residual atmospheric contributions. Error bars 

represent 95% confidence intervals. ..........................................................................................4

Figure 3. Selected regions of single-shot, single laser pulse emission spectra (in air) of highpurity Al, three National Institute of Standards & Technology (NIST) Al alloy standard 

reference materials of known elemental content, and alumina. .................................................5

Figure 4. Carbon (left) and AlO (right) emission intensities (normalized to the argon line at 

763 nm) for five Al substrates with and without RDX residue. Error bars represent 95% 

confidence intervals. ..................................................................................................................5

Figure 5. Selected regions of double-pulse spectra of a) Al, b) Cu, c) Ni, d) Sn, and e) Ti 

under argon with (red trace) and without (black trace) RDX. Unidentified lines 

correspond to argon or metal substrate emission. ......................................................................6

Figure 6. Contour plot of the C, N, and O (left) and N, CN, and O (right) emission intensities 

of RDX on five different metal substrates (Al, Cu, Ni, Sn, and Ti). The concentration of 

the O is decreased by the presence of C and CN. ......................................................................6

Figure 7. As the concentration of Al in the RDX/Al mixture was increased, the substrate 

emission lines decreased (due to increased residue surface coverage), and the Al, AlO, 

and C2 emission lines increased. ................................................................................................7
v 

Acknowledgments 

I wish to acknowledge the contributions of Dr. Frank C. De Lucia, Jr. (U.S. Army Research 

Laboratory, Weapons and Materials Research Directorate). Dr. De Lucia assisted with the 

experimental setup and provided helpful input on the experimental plan and data analysis. 
vi 

INTENTIONALLY LEFT BLANK. 
1 

1. Objective 

The feasibility of a novel approach for studying the chemical reactions between metallic 

nanoparticles and molecular explosives has been demonstrated. This method is based on the 

production of nanoparticles in a laser-induced plasma and the simultaneous observation of the 

time-resolved atomic and molecular emission characteristic of the species involved in the 

intermediate chemical reactions of the nanoenergetic material in the plasma.

2. Approach 

It is essential to understand the chemical mechanisms of combustion, thermal explosion, and 

detonation in order to develop more efficient explosives and propellants. It is well known that 

two-component explosives consisting of metal particle fuels and oxidizers can produce more 

than twice as much energy as high performance molecular explosives alone (1). 

Because of the high heat of formation for alumina (Al2O3), the addition of aluminum (Al) to 

explosive formulations results in a considerable increase in the heat of explosion. Al is rapidly 

oxidized by oxygen (O, O2), carbon dioxide (CO2), water (H2O), and possibly other species such 

as nitric oxide (NO), nitrous oxide (N2O), and nitrogen dioxide (NO2) to form aluminum 

monoxide (AlO) before reaching its final equilibrium state, Al2O3 (2). Recently, the presence of 

Al was shown to promote the ejection process of carbon from the intermediate products of RDX 

pyrolysis, which decreases rocket propellant performance (3). Conventional formulations of 

energetic materials containing Al particles to improve the performance of explosives and 

propellants use particles with a mean diameter of ~30 m, but nanoscale materials offer the 

possibility of faster energy release, more complete combustion, and greater control over 

performance (1, 4). The development of nanoenergetic materials has been hampered by the lack 

of fundamental knowledge of the chemical dynamics involved. 

Previous experiments have demonstrated that ablation of an Al target with a pulsed laser 

produces Al nanoparticles with a mean primary particle size of 1–100 nm (depending on laser 

pulse duration and fluence as well as carrier gas type and pressure) (5, 6). Here, we have 

combined the ablation of thin-film residues of molecular explosives (~2.5 g/mm2) on Al 

substrates (generating nanoenergetic particles) with the observation of time-resolved optical 

emissions from the resulting high-temperature plasma. The relative concentrations of carbon (C), 

diatomic carbon (C2), CN, Al, AlO, hydrogen (H), nitrogen (N), and O (as well as any other 

atomic, molecular, or ionic species emitting from 200–940 nm) were tracked during the lifetime 

of the plasma (typically <1 ms). Because the laser pulse duration is too short to directly initiate 

the explosives (<10 ns) and the heat deposited by the laser is rapidly conducted through the 
2 

substrate, detonation of the explosive material was not observed. The potential advantages to this 

approach include (1) little or no sample preparation is needed (the laser directly ablates the 

explosive and substrate material); (2) the intermediate chemical reactions of the nanoenergetic 

material can be studied on a small scale (microgram quantities), eliminating the need for a shock 

tube or other explosive containment apparatus; (3) the properties of the laser (pulse energy, 

wavelength, pulse duration) can be tuned to control the size and distribution of the particles 

formed; and (4) high-resolution, time-resolved relative concentrations of a large number of 

atomic and molecular species can be tracked simultaneously. 

The first task was to confirm the results of Song et al. (3), who observed an increase in C2

emission when the concentration of micro-aluminum powder (3–9 m) was increased. Unlike 

the previous experiment, our experiment (1) did not require the use of a shock tube, (2) involved 

laser-generated nanometer-sized Al particles rather than commercial micrometer-sized particles, 

and (3) enabled us to track the relative concentrations of a large number of atomic and molecular 

species simultaneously. Previous work by McNesby and coworkers (7) demonstrated that the 

primary source of oxygen for the oxidation of an ablated Al target is from air, so in order to 

determine whether the Al nanoparticles are being oxidized by the decomposition products of the 

RDX or from the air, the experiments were carried out under an inert argon atmosphere as well. 

The second task was to optimize the production of nanoparticles in the laser-induced plasma. 

Since the reactivity of the Al nanoparticles has been shown to increase with decreasing size (8), 

we would expect to see a difference in the emission intensities of the reaction species as the 

average size and distribution of the energetic materials in the plasma was varied. We compared 

the relative concentrations of the reaction species under different atmospheric conditions (air vs. 

argon) and at different laser pulse energies. The use of two successive nanosecond laser pulses 

(separated by a several s delay), where the second laser pulse re-excites and further atomizes 

the ablated material (9), was also investigated. 

The third task was to investigate other types of nanoenergetic materials. While the initial studies 

were performed with an RDX residue on an Al substrate, an additional 67 substrates were 

studied, including both pure metals (silver [Au], copper [Cu], indium [In], titanium [Ti], etc.) and 

metal alloys with known trace metal concentrations. In addition to observing the effect of trace 

metals on the plasma chemistry, commercially available Al powder was mixed with the RDX 

residue and added to non-Al substrates in order to determine the effect of the Al nanoparticles on 

the reaction chemistry. Finally, the chemical reactions of 10 different organic explosives (and 3 

non-explosive organic materials) on an Al substrate were studied (10). 
3 

3. Results 

Time-resolved emission spectra were acquired with an echelle/intensified charge-coupled device 

(ICCD) detector (Catalina Scientific SE200 and Apogee AP2Ep ICCD, tint=1 μs) at various 

delays (tdelay) relative to the plasma generated using two Big Sky CFR400 lasers (2×225 mJ, 

t=2 μs). Emission spectra generated with a single-pulse laser in an argon atmosphere and a 

double-pulse laser in air were acquired. The wavelengths of the spectral lines in the emission 

spectra are characteristic of the excited atoms, ions, and molecules in the laser-induced plasma, 

while the intensity of the emitted light is proportional to the concentration of the emitting 

species. Although the relative emission intensities for the atomic and molecular species of 

interest were relatively constant for the first 6 μs of the plasma lifetime in the single-pulse argon 

plasma, the emission intensities for the double-pulse spectra at various delays showed some 

interesting trends. Figure 1 shows that as the continuum emission observed at tdelay=0 decreases 

with time, the atomic N, O, and H concentrations slowly decrease, the C concentration remains 

fairly constant, and the molecular species concentrations (CN, C2, and AlO) increase as 

recombination reactions in the cooling plasma result in their formation. The excitation 

temperature, calculated from the Al emission lines using the Boltzmann method, decreases from 

about 7000 K at tdelay=0 to around 3700 K at tdelay=10 μs. 

Figure 1. Time-resolved double-pulse spectra of RDX on Al in air at various delay times (left). While the 

concentration of atomic species slowly decreases over the first 11 s (right), recombination reactions 

result in higher concentrations of CN, C2, and AlO as the plasma cools. 

The effect of laser pulse energy on the RDX/Al chemical reactions was studied using a 

Continuum Surelite laser system with an echelle/electron multiplying charge-coupled device 

(EMCCD) detector (Catalina Scientific EMU-65 and Andor iXon EMCCD, tdelay=1 μs, 

tint=50 μs). Spectra of RDX on a high-purity Al substrate were acquired under argon with several 

laser ablation conditions: (1) 210 mJ single-pulse, (2) 420 mJ single-pulse, (3) 2×210 mJ doublepulse (t=2 μs), and (4) 2×420 mJ double-pulse (t=2 μs). The calculated excitation temperature 

of the plasma in all four cases is essentially identical (~8500 K). The emission spectra show that 

Double Pulse (Air)

0

0.1

0.2

0.3

0.4

0.5

0 1 2 3 4 5 6 7 8 9 10

Gate Delay (s)

Normalized Intensities

C 247

CN 388

C2 516

H 656

N 746

O 777

AlO 484
4 

increasing the laser energy from 210 to 420 mJ increased the overall spectral emission intensity 

and increased the relative AlO concentration (figure 2). The increase in AlO concentration is 

most likely a result of the higher reactivity of the Al particles in the plasma. A comparison of the 

single-pulse 420 mJ spectra and the double-pulse (420 mJ total) spectra shows that although the 

RDX signature is much stronger for the double-pulse ablation, the AlO emission decreases. 

Although double-pulse excitation produces smaller particle sizes, it also reduces the amount of 

atmospheric oxygen entrained in the laser-induced plasma (the argon gas flow reduces but does 

not eliminate atmospheric interference) (9). Therefore, there is less atmospheric O available to 

react with the Al in the double-pulse case (figure 2). Increasing the total double-pulse energy 

from 2×210 to 2×420 mJ results in an increase in AlO emission, as expected. 

Figure 2. Comparison of O and AlO intensities for different laser pulse energies. The O in the blank Al spectra is 

primarily from residual atmospheric contributions. Error bars represent 95% confidence intervals. 

Single-pulse spectra of 68 metal substrates were acquired in air with a LIBS2500+ 7-channel 

CCD spectrometer by Ocean Optics (200-940 nm, tdelay=1.5 μs, tint=1 ms) using a Big Sky 

CFR400 laser (115 mJ) for the laser ablation and excitation. Samples surveyed included highpurity Al (99.999%), Cu (99.999%), nickel (Ni) (99.98%), tin (Sn) (99.998%), and Ti (99.998%) 

as well as numerous metal alloys including brass, lead, and steel. Differences in the spectra were 

observed based on trace element additives and impurities. For example, figure 3 shows the 

spectral differences observed in five Al-containing substrates. Comparison to the known trace 

element concentrations in the substrates confirmed the linear relationship between the observed 

emission intensities and elemental content. RDX residue dissolved in acetonitrile (2.5 μg/mm2

; 

~1 μg of RDX sampled with each laser shot) was applied to a subset of the substrates surveyed, 

and double-pulse spectra under argon were acquired with the echelle/EMCCD detector 

(tdelay=1 μs, tint=50 μs) from plasmas generated by the Continuum Surelite laser system 

(2×420 mJ, t=2 μs). Differences in the chemistry related to trace element content were 

observed (figure 4). The high-purity Al sample resulted in the strongest C and AlO emission 

intensity in the presence of RDX. 

0

5

10

15

20

25

30

35

40

45

50

210mJ 420mJ 210-210mJ 420-420mJ

AlO intensity

Al

Al+RDX

0

500

1000

1500

2000

2500

3000

210mJ 420mJ 210-210mJ 420-420mJ

O intensity

Al

Al+RDX
5 

Figure 3. Selected regions of single-shot, single laser pulse emission spectra (in air) of high-purity Al, three 

National Institute of Standards & Technology (NIST) Al alloy standard reference materials of known 

elemental content, and alumina. 

Figure 4. Carbon (left) and AlO (right) emission intensities (normalized to the argon line at 763 nm) for five Al 

substrates with and without RDX residue. Error bars represent 95% confidence intervals. 

Selected regions of spectra from the five high-purity substrates with and without RDX (double 

pulse under argon) are shown in figure 5. The increase in the C, H, N, O, and CN emission with 

the presence of RDX (red traces) is clearly visible. The highest excitation temperatures of the 

RDX/metal plasmas correspond to Ti>Al>Cu>Sn>Ni. The extent of ionization in each plasma 

(represented by the ion/neutral ratio) follows the same trend as the temperature. The properties 

of the substrate have a clear effect on the chemistry of the RDX in the plasma, as shown in 

figure 6. The concentration of atomic O is highest in conditions of low C and low CN. This can 

be explained by the reaction of O with C or CN to form CO (and subsequently CO2) via the 

following reactions (11):

C + O + M → CO + M, 

CN + O → CO + N, 

CO + O → CO2. 

0

0.2

0.4

0.6

0.8

1

1.2

1.4

Al Al1715 Al1259 Al1256b Alumina

C/Ar

Blank

Blank+RDX

0

0.05

0.1

0.15

0.2

0.25

0.3

Al Al1715 Al1259 Al1256b Alumina

AlO/Ar

Blank

Blank+RDX
6 

Figure 5. Selected regions of double-pulse spectra of a) Al, b) Cu, c) Ni, d) Sn, and e) Ti under argon with (red 

trace) and without (black trace) RDX. Unidentified lines correspond to argon or metal substrate emission. 

Figure 6. Contour plot of the C, N, and O (left) and N, CN, and O (right) emission intensities of RDX on five 

different metal substrates (Al, Cu, Ni, Sn, and Ti). The concentration of the O is decreased by the 

presence of C and CN. 

The effect of Al on the chemistry of RDX was studied by mixing Al powder (<75 μm) with 

RDX in varying concentrations (1:0, 1:1, 1:2, and 1:4) and applying the RDX/Al mixture to the 

five high-purity substrates shown in figure 5. The plasma temperature for each substrate 

increased by as much as 50% with the addition of Al powder to the RDX. As the concentration 

of Al powder was increased, the substrate emission lines decreased and the Al emission lines 

increased (figure 7). While the C, H, N, H, and CN emission lines decreased with increasing Al, 

the C2 and AlO increased on all substrates (figure 7). This result clearly confirms the conclusions 

of Song et al. (3), who observed the increase in C2 and AlO emission with increasing Al content 

O Intensity

C Intensity

0.4 0.6 0.8 1.0 1.2 1.4

N Intensity

0.02

0.03

0.04

0.05

0.06

0.0 

0.5 

1.0 

1.5 

2.0 

4.0 

O Intensity

N Intensity

0.02 0.03 0.04 0.05 0.06

CN Intensity

0.02

0.04

0.06

0.08

0.10

0.12

-4 

-2 

0 

2 

4 

12 
7 

during an aluminized-RDX explosion in a shock tube. The higher the concentration of Al in the 

plasma, the more O the Al scavenges to form AlO, and the less O available to react with the C to 

form CO. This results in an increase in condensed phase C aggregate (soot) and C2. 

Figure 7. As the concentration of Al in the RDX/Al mixture was increased, the substrate emission lines decreased 

(due to increased residue surface coverage), and the Al, AlO, and C2 emission lines increased.

4. Conclusions 

Time-resolved, broadband emission of chemical species involved in the reaction of RDX and 

various metal nanoparticles was observed. The observations of Song et al. (3) were confirmed 

using the promising new methodology presented here for investigating the chemical processes 

involved in nanoenergetic material reactions. The time-evolution of species formation, the 

effects of laser pulse energy, and the effects of trace metal content on chemical reactions were 

studied. Future improvements to the experimental setup should include the incorporation of 

online monitoring of particle size distribution (12) and the monitoring of mid-IR emission from 

the plasma to obtain information on the concentration of important species such as CO, CO2, 

NO, and NO2 in the plasma (13). Additional experiments to be performed include tuning the 

laser properties such as pulse duration and wavelength to adjust the size and size distribution of 

the ablated particles, and exploring other explosive formulations such as TNT/Al, Al/Teflon, etc. 

Although the optical emission spectroscopy of explosive materials has been used for the 

detection and identification of explosives (14), to the best of our knowledge, this work represents 

the first use of high-resolution optical emission to study the chemical reactions of energetic 

materials in laser-induced plasmas. This method provides the U.S. Army Research Laboratory 

(ARL) with new capabilities for nanoenergetic material evaluation and formulation, and has 

several advantages: (1) minimal sample preparation is required, (2) real-time, time-resolved 

analysis of chemical reaction intermediates can be achieved, (3) it uses small-scale, hightemperature reactions that do not require containment equipment, and (4) the ratio of 

fuel/oxidizer is not limited by the need to cast the explosive formulation. The chemical reactions 
8 

that occur between Al nanoparticles and explosives are not well understood. By monitoring the 

emission intensity of the different reactant species as a function of time, a better understanding of 

the chemistry of metallic nanoparticles and explosives at high temperatures could be achieved, 

eventually enabling the development of improved explosive formulations with higher explosive 

power and fewer harmful byproducts. 
9 

5. References 

1. Yang, Y.; Sun, Z.; Wang, S.; Dlott, D. D. Fast Spectroscopy of Laser-Initiated 

Nanoenergetic Materials. J. Phys. Chem. B 2003, 107 (19), 4485–4493. 

2. Ji, Z.; Shufen, L. Aluminum Oxidation in Nitramine Propellant. Propellants Explos. 

Pyrotech. 1999, 24 (4), 224–226. 

3. Song, Y.; Jing-he, W.; Yan-ping, W.; Guo-dong, W.; Xiang-dong, Y. Optical Investigation 

of Shock-produced Chemical Products in Pseudo-aluminized Explosive Powders Explosion. 

J. Phys. D 2007, 40, 3541–3544. 

4. Brousseau, P.; Anderson, C. J. Nanometric Aluminum in Explosives. Propellants Explos. 

Pyrotech. 2002, 27 (5), 300–306. 

5. Ullmann, M.; Friedlander, S. K.; Schmidt-Ott, A. Nanoparticle Formation by Laser 

Ablation. J. Nano. Res. 2002, 4 (6), 499–509. 

6. Amoruso, S.; Bruzzese, R.; Vitiello, M.; Nedialkov, N. N.; Atanasov, P. A. Experimental 

and Theoretical Investigations of Femtosecond Laser Ablation of Aluminum in Vacuum. J. 

Appl. Phys. 2005, 98 (4), 044907. 

7. Piehler, T. N.; DeLucia Jr., F. C.; Munson, C. A.; Homan, B. E.; Miziolek, A. W.; McNesby, 

K. L. Temporal Evolution of the Laser-induced Breakdown Spectroscopy Spectrum of 

Aluminum Metal in Different Bath Gases. Appl. Opt. 2005, 44 (18), 3654–3660. 

8. Park, K.; Lee, D.; Rai, A.; Mukherjee, D.; Zachariah, M. R. Size-resolved Kinetic 

Measurements of Aluminum Nanoparticle Oxidation with Single Particle Mass 

Spectrometry. J. Phys. Chem. B 2005, 109 (15), 7290–7299. 

9. Babushok, V. I.; De Lucia Jr., F. C.; Gottfried, J. L.; Munson, C. A.; Miziolek, A. W. 

Double Pulse Laser Ablation and Plasma: Laser Induced Breakdown Spectroscopy Signal 

Enhancement. Spectrochim. Acta, Part B 2006, 61, 999–1014. 

10. De Lucia Jr., F. C.; Gottfried, J. L. Characterization of a Series of Nitrogen-rich Molecules 

Using Laser-induced Breakdown Spectroscopy. Propellants, Explos., Pyrotech., submitted 

2009. 

11. Babushok, V. I.; DeLucia, F. C.; Dagdigian, P. J.; Gottfried, J. L.; Munson, C. A.; 

Nusca, M. J. ; et al. Kinetic Modeling Study of the Laser-induced Plasma Plume of 

Cyclotrimethylenetrinitramine (RDX), Spectrochim. Acta, Part B 2007, 62B (12), 1321–

1328. 
10 

12. Sattari, R.; Dieling, C.; Barcikowski, S.; Chichkov, B. Laser-based Fragmentation of 

Microparticles for Nanoparticle Generation. J. Laser Micro. Nanoengineer. 2008, 3 (2), 

100–105. 

13. Yang, C.S.-C.; Brown, E. E.; Hommerich, U. H.; Trivedi, S. B.; Samuels, A. C.; 

Snyder, A. P. Mid-infrared Emission from Laser-induced Breakdown Spectroscopy. Appl. 

Spectrosc. 2007, 61 (3), 321–326. 

14. Gottfried, J. L.; De Lucia Jr., F. C.; Munson, C. A.; Miziolek, A. W. Laser-induced 

Breakdown Spectroscopy for Detection of Explosives Residues: A Review of Recent 

Advances, Challenges, and Future Prospects. Anal. Bioanal. Chem. 2009, 395, 283. 
11 

6. Transitions 

Manuscripts in preparation include (1) a detailed comparison and analysis of the 68 substrates 

studied in this work and (2) a comprehensive evaluation of the effects of laser pulse energy and 

atmospheric contributions. In addition, this experimental method has been applied to the study of 

the chemical reactions of other explosives besides RDX, including TNT and eight novel highnitrogen explosives (10).
12 

List of Symbols, Abbreviations, and Acronyms 

Al aluminum 

Al2O3 alumina 

AlO aluminum monoxide 

ARL U.S. Army Research Laboratory 

Au silver 

C carbon 

C2 diatomic carbon 

CO2 carbon dioxide 

Cu copper 

EMCCD electron multiplying charge-coupled device 

H hydrogen 

H2O water 

ICCD intensified charge-coupled device 

In indium 

N nitrogen 

N2O nitrous oxide 

NIST National Institute of Standards & Technology 

NO nitric oxide 

NO2 nitrogen dioxide 

O oxygen 

Sn tin 

Ti titanium 
13 

No. of 

Copies Organization 

 1 ADMNSTR 

 ELEC DEFNS TECHL INFO CTR 

 ATTN DTIC OCP 

 8725 JOHN J KINGMAN RD STE 0944 

 FT BELVOIR VA 22060-6218 

 1 CD US ARMY RSRCH LAB 

 ATTN RDRL CIM G T LANDFRIED 

 BLDG 4600 

 ABERDEEN PROVING GROUND MD 

 21005-5066 

 3 CDS US ARMY RSRCH LAB 

 ATTN IMNE ALC HRR 

 MAIL & RECORDS MGMT 

 ATTN RDRL CIM L TECHL LIB 

 ATTN RDRL CIM P TECHL PUB 

 ADELPHI MD 20783-1197 

 12 CDS US ARMY RSRCH LAB 

 4 HCS RDRL WML A 

 F DE LUCIA (1 HC, 1 CD) 

 J GOTTFRIED (1 HC, 1 CD)

 W OBERLE (1 HC, 1 CD) 

 RDRL WML B 

 R PESCE-RODRIGUEZ (1 HC, 1 CD) 

 B HOMAN 

 J MORRIS 

 RDRL WML C 

 S AUBERT 

 K MCNESBY 

 RDRL WML D 

 M NUSCA 

 M MCQUAID 

 RDRL WMP 

 P BAKER 

 RDRL WM 

 B FORCH 

 ABERDEEN PROVING GROUND MD 

 21005-5066 

TOTAL: 21 (1 ELEC, 4 HCS, 16 CDS) 
14 

INTENTIONALLY LEFT BLANK.