Detonation Chemistry Of Glycidyl Azide Polymer

1995 ◽  
Vol 418 ◽  
Author(s):  
Ping Ling ◽  
Jill Sakata ◽  
Charles A. Wight

AbstractThe initial step of chemical reaction initiated by laser-generated shock waves has been observed in glycidyl azide polymer (GAP) in condensed phase. Shocks are generated by pulsed laser vaporization of thin aluminum films and launched into adjacent films of GAP at 77 K. Comparison of FIIR spectra obtained before and after shock passage shows that initial reaction involves elimination of molecular nitrogen from the azide functional groups of the polymer. The shock arrival time has been measured by a velocity interferometer as a function of thickness of GAP and laser fluence. The shock pressure has been calculated by using a universal liquid state Hugoniot. A simple model is proposed to calculate shock velocity and pressure as a function of laser fluence. The results are in agreement with experimental data.

2021 ◽  
Vol 17 (4) ◽  
pp. 16-31
Author(s):  
Yury P. Snitovsky

The work is devoted to the study of the stabilizing effect of yttrium additions during the deposition of thin aluminum films, which are used for the manufacture of elements of micro- and nanoelectronic devices. The surfaces of Al films doped with aluminum oxide were investigated using a scanning electron microscope before and after annealing for 300420 s at a temperature of 500 C. It is shown that fine alumina particles are uniformly distributed on the surface of the films during thermal evaporation of a wire made of an Al Al2O3 alloy. By the method of quantitative metallography, the content of the AlxOy phase in the Al films was determined: when spraying wire from the Al Al2O3 alloy, its content was 1012% of the mass fraction; when spraying wire made of Al Al2O3 alloy and Al wire in a ratio of 50:50 1% mass fraction.


Author(s):  
Ray Wu ◽  
G. Ruben ◽  
B. Siegel ◽  
P. Spielman ◽  
E. Jay

A method for determining long nucleotide sequences of double-stranded DNA is being developed. It involves (a) the synchronous digestion of the DNA from the 3' ends with EL coli exonuclease III (Exo III) followed by (b) resynthesis with labeled nucleotides and DNA polymerase. A crucial factor in the success of this method is the degree to which the enzyme digestion proceeds synchronously under proper conditions of incubation (step a). Dark field EM is used to obtain accurate measurements on the lengths and distribution of the DNA molecules before and after digestion with Exo III, while gel electrophoresis is used in parallel to obtain a mean length for these molecules. It is the measurements on a large enough sample of individual molecules by EM that provides the information on how synchronously the digestion proceeds. For length measurements, the DNA molecules were picked up on 20-30 Å thick carbon-aluminum films, using the aqueous Kleinschmidt technique and stained with 7.5 x 10-5M uranyl acetate in 90% ethanol for 3 minutes.


Author(s):  
Yutaka Wada ◽  
S. Hatano ◽  
Ayana Banno ◽  
Yo Kawabata ◽  
Hiroshi Hasegawa ◽  
...  

1984 ◽  
Vol 35 ◽  
Author(s):  
S. Williamson ◽  
G. Mourou ◽  
J.C.M. Li

ABSTRACTThe technique of picosecond electron diffraction is used to time resolve the laser-induced melting of thin aluminum films. It is observed that under rapid heating conditions, the long range order of the lattice subsists for lattice temperatures well above the equilibrium point, indicative of superheating. This superheating can be verified by directly measuring the lattice temperature. The collapse time of the long range order is measured and found to vary from 20 ps to several nanoseconds according to the degree of superheating. Two interpretations of the delayed melting are offered, based on the conventional nucleation and point defect theories. While the nucleation theory provides an initial nucleus size and concentration for melting to occur, the point defect theory offers a possible explanation for how the nuclei are originally formed.


Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 278 ◽  
Author(s):  
Jinghui Hu ◽  
Weiqiang Tang ◽  
Yonghui Li ◽  
Jiyu He ◽  
Xiaoyan Guo ◽  
...  

A new energetic curing reagent, Glycidyl azide polymer grafted tetrafunctional isocyanate (N100-g-GAP) was synthesized and characterized by FT-IR and GPC approaches. Polytriazole polyethylene oxide-tetrahydrofuran (PTPET) elastomer was prepared by N100-g-GAP and alkynyl terminated polyethylene oxide-tetrahydrofuran (ATPET). The resulting PTPET elastomer was fully characterized by TGA, DMA, FTIR and mechanical test. The above analysis indicates that PTPET elastomers using N100-g-GAP as curing reagent have the potential for use in propellants. The overall formulation test of the composite propellants shows that this curing system can effectively enhance mechanical strength and bring a significant improvement in the interface interaction between the RDX & AP particles and binder matrix.


2009 ◽  
Vol 114 (6) ◽  
pp. 3360-3368 ◽  
Author(s):  
S. K. Manu ◽  
T. L. Varghese ◽  
S. Mathew ◽  
K. N. Ninan

1999 ◽  
Vol 594 ◽  
Author(s):  
Alex A. Volinsky ◽  
Neville R. Moody ◽  
William W. Gerberich

AbstractThe practical work of adhesion has been measured in thin aluminum films as a function of film thickness and residual stress. These films were sputter deposited onto thermally oxidized silicon wafers followed by sputter deposition of a one micron thick W superlayer. The superlayer deposition parameters were controlled to produce either a compressive residual stress of 1 GPa or a tensile residual stress of 100 MPa. Nanoindentation testing was then used to induce delamination and a mechanics based model for circular blister formation was used to determine practical works of adhesion. The resulting measured works of adhesion for all films between 100 nm and 1 μm thick was 30 J/m2 regardless of superlayer stress. However, films with the compressively stressed superlayers produced larger blisters than films with tensile stressed superlayers. In addition, these films were susceptible to radial cracking producing a high variability in average adhesion values.


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