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The current demilitarization processes employ open burning/open detonation which is not permitted by the environmental protection agency. Therefore, a systematic study has been carried out to convert waste/rejected nitramine propellant (NP) and fuel-rich-based propellant (FRP) into liquid fertilizer by digesting in dilute nitric acid followed by neutralization with potassium hydroxide and phosphoric acid. The obtained liquid fertilizers were fully characterized for nitrate, phosphate and ammonium ions along with potassium. Further, the effect of liquid fertilizers of NP and FRP on cluster bean plants was studied by taking different concentrations from 25 to 150 mL, and their effects on germination pattern, shoot growth, thickness of stem, size and number of leaves, number of pods and length over a full-grown period of plants were investigated. The results reveal that the germination index increases as the content of liquid fertilizer increases and the same trend was observed with respect to root and shoot growth. Also, broadness and the number of leaves showed an encouraging effect as concentration increases. Further, the final product, i.e. the number of pods of cluster bean and length in each pod was found to be more for liquid fertilizer of NP compared to FRP-based liquid fertilizer.

High burning rate composite propellants are achieved by incorporation of fine particles of oxidizer, transition metal oxides, and liquid ballistic modifiers. However, they pose processing problems, inertness to the composition and migration related issues. To overcome such problems, an attempt was made to incorporate ferrocenyl grafted HTPB as a burning rate modifier by partly replacing HTPB from 10 % to 50 % using TDI/ IPDI bicurative system and to study their processability in terms of viscosity, mechanical, thermal, sensitivity, and ballistic properties. The data on viscosity reveal that there is a marginal enhancement in end of mix viscosity as percentage of ferrocenyl grafted HTPB increases. The mechanical data reveal that tensile strength and elastic modulus increases, whereas percentage elongation decreases compared to base composition. The results on thermal properties infer that, as the percentage of ferrocenyl grafted HTPB increases, onset decomposition temperature decreases. The impact and friction sensitivity data also envisage that sensitivity increases in comparison to base composition. The data on ballistic properties revealed that there is ca. 53 % increase in burning rate, while decrease in “n” value from 0.39 to 0.2 was obtained compared to base composition.

The incorporation of nanoaluminum in an 86% solid composite propellant formulation poses processing problems when following conventional methods. Therefore, to accommodate an optimum percentage of nanoaluminum in such formulations, a new bicurative system was introduced. Summarizing in the present study, a bicurative system consisting of toluene diisocyanate and isophorone diisocyanate was chosen to enable incorporation of 18% nanoaluminum powder (93 nm) in place of 18% micrometer-sized Aluminum powder. The developed compositions were studied in detail for their mechanical, thermal, sensitivity, and ballistic properties. The mechanical properties data, such as tensile strength, E modulus, and percentage elongation, are almost on par with the values obtained with micrometer-sized aluminum powder using a developed bicurative system. The results of thermal properties reveal that, as the percentage of nanoaluminum increases in the composition, the onset decomposition temperature decreases. The impact and fric...

The performance of solid propellants is often tailored by incorporating energetic materials such as novel oxidizers, energetic binders and ballistic modifiers. Metal oxide nanoparticles are known for their persuasivenature to modify burning rate ofammonium perchlorate based composite propellants. In the present work, nano iron oxide and poly (1-(3-nitrophenyl)-1H-1,2,3-triazol-4-yl) acrylate are incorporated in the composite propellant formulation by partly replacing coarse ammonium perchorate (AP) as well as hydroxy terminatined polybutadiene (HTPB), respectively, and different properties were evaluated. The mechanical properties data revealed that on increasing the percentage of polymer in the composition by partly replacing HTPB, there is an increase in tensile strength while decreasing elongation percentage. Thedata of ballistic properties revealed that on incorporation of nano iron oxide in the composition enhances the burning rate while on partial replacement of HTPB with polymer there is a decrease in burning rate from 11.95 mm s−1 to 8.75 mm s−1, respectively was observed.

This article reports ways to functionalize hydroxyl-terminated polybutadiene (HTPB) by azide groups to impart energetic properties to the polymer. Two different synthetic approaches were explored to synthesize azide-functionalized hydroxyl-terminated polybutadiene (azide-HTPB). The functionalized polymer was analyzed for structural confirmation and determination of important physical and thermal properties. Azide-HTPB obtained by azidation of 10% double bonds of HTPB showed viscosity of 11 Pa.s and a glass transition temperature of −66°C.

Propellants, visco-elastic in nature, show time and temperature dependent behaviour on deformation. Hence, the time–temperature superposition principle may be applied to the visco-elastic properties of propellants. In the present study, dynamic mechanical analyser (DMA) was used to evaluate the dynamic mechanical properties and quantify the storage life of four different propellants based on hydroxyl terminated polybutadiene, aluminium and ammonium perchlorate having different burning rates ranging from 5 mm/s to 25 mm/s. Each sample was given a multi-frequency strain of 0.01 per cent at three discrete frequencies (3.5 Hz, 11 Hz, 35 Hz) in the temperature range - 80 °C to + 80 °C. The storage modulus, loss modulus, tan delta and glass transition temperature (Tg) for each propellant samples have been evaluated and it is observed that all the propellants have shown time (frequency) and temperature dependent behaviour on deformation. A comparison of the log aT versus temperature curves (where aT is horizontal (or time) shift factor) for all four propellants indicate conformance to the Williams–Landel–Ferry (WLF) equation. The master curves of storage modulus (log E versus log ω plots) were generated for each propellant. A plot of E versus time for all propellants was generated up to 3 years, 6 years, and 10 years of time, respectively. The drop in the storage modulus below the acceptable limit with time may be used to predict the shelf life of the propellant. Defence Science Journal, 2012, 62(5), pp.290-294 , DOI:http://dx.doi.org/10.14429/dsj.62.2480

Rockets are powered by composite solid propellant, which is a heterogeneous system consisting of solid oxidizer and metallic fuel dispersed in a polymeric fuel binder matrix. The slurry casting technique under vacuum/gravity condition is well-established for performing a different class of large sized case bonded rocket motors. During propellant casting, the flow rate of slurry is a very critical parameter as it affects the product quality. The casting rate is governed by sufficient degassing and viscosity buildup due to the progress of cure reaction. In the present study, casting rate and casting time have been numerically evaluated for fixed and varying percentages of valve opening, different viscosity of slurry, and different pressure drop (driving force). The velocity profile of propellant slurry inside feeding pipe and valve has also been evaluated. Furthermore, to get a flawless grain and to predict the slurry casting rate, a microscopic analysis has been carried out to model the flow behaviour of composite propellant slurry, where the momentum conservation law has been applied to express the mathematical model in an analytical form. The resulting differential and algebraic equations have been solved numerically using MATLAB, computing software. The numerical analysis is useful for designing new casting set-up and for giving the idea of maximum casting rate, which is achievable for given casting set-up and rheological properties of propellant slurry.

The objective of the presented study is to report on retrospectively collected data on long-term outcome and toxicity and prospective assessment of quality of life (QoL) and Voice-Handicap Index (VHI) of patients with T1a glottic cancer treated with radiotherapy. Between 1985 and 2011, 549 patients were treated. Endpoints were local control (LC), toxicity, QoL and VHI. After a median follow-up of 93 months, the actuarial rates of LC were 91, and 90 % at 5- and 10-years, respectively. Continuing smoking (p < 0.001) and anaemia (p = 0.02) were significantly correlated with poor LC on univariate analysis and fractionation schedule did not show significant correlation (p = 0.08). On multivariate analysis, only continuing smoking retained significance (p = 0.001). These patients had also significantly increased incidence of second primary tumour and lower overall survival rates. The incidence of grade a parts per thousand yen2 late xerostomia and dysphagia were 10 and 6 %, respectively. Slight and temporary deterioration of QoL-scores was reported. The scores on the EROTC-QOL-H&N35 dysphagia and xerostomia at 24 months were -2 and -3, compared to baseline, respectively. VHI improved significantly from 34 at baseline to 21 at 24 months. Patients who continued smoking had significantly worse VHI. In conclusion, excellent outcome with good QoL and VHI were reported. Patients who continued smoking after radiotherapy had significantly poor LC and worse VHI. The current study emphasizes the importance of smoking cessation and the non-inferiority of hypofractionated schemes in terms of outcome and VHI. At our institution, phase II study is going to evaluate the role of single vocal cord irradiation with high fraction dose.

The calorimetric value (cal-val) of solid rocket propellants and explosives is determined in the presenceof inert atmosphere using industrial nitrogen gas. However, due to presence of trace amount of oxygen, the cal-val is not always correct. To avoid such inaccuracy in cal-val, a systematic study has been carried out by takingdifferent types of solid propellant samples having burning rate in the range of 5 mm/s − 30 mm/s at different pressures.The data obtained were acquired using industrial nitrogen, ultra high pure nitrogen (UHP-N2), ultra high pureargon (UHP-Ar), air and ultra high pure oxygen (UHP-O2). The data reveal that cal-val is highest in the case ofUHP-O2 due to complete combustion while in the case of air and industrial nitrogen it is found to be substantiallyless. Moreover, the cal-val in the presence of UHP-N2 and UHP-Ar meets the standard value with reproducibility.The results, further, confirm that for authentic cal-val, the most suitable environment is UHP-N2/UHP-Ar. Defence Science Journal, 2013, 63(5), pp.467 -472 , DOI:http://dx.doi.org/10.14429/dsj.63.2896

Nanomaterials are finding applications in explosives and propellant formulations due to their large surface area and high surface energy. This high surface energy is responsible for the low activation energy and increase in burning rate of the composition. Therefore, a successful attempt has been made to prepare nano-ammonium perchlorate using a nonaqueous method by dissolving ammonium perchlorate (AP) in methanol followed by adding the dissolved AP to the hydroxyl-terminated polybutadiene (HTPB), homogenization, and vacuum distillation of the solvent. The nano-AP thus formed was characterized using a NANOPHOX particle size analyzer (Sympatec, Germany), transmission electron microscopy (FEI, Hillsboro, OR), X-ray diffraction (PANalytical B.V., The Netherlands) and scanning electron microscopy (Ikon Analytical Equipment Pvt. Ltd., Mumbai, India) for particle size, purity, and morphology, respectively. The thermal behavior of nano-AP was also studied using differential thermal analysis–thermo gravimetric an...

The optimal treatment of sinonasal undifferentiated carcinoma (SNUC) remains unclear. We report our results on the outcome and toxicity of patients with SNUC treated by a combined modality and attempt to define the optimal treatment strategies by reviewing the literature. Between 1996 and 2010, 21 consecutive patients with SNUC were treated by any combination of surgery, chemotherapy and radiotherapy. End points were local control (LC), regional control (RC), disease-free (DFS), cause-specific (CSS) overall survival (OS), and late toxicity. Organ preservation was defined as visual preservation without orbital exenteration. After median follow-up of 54 months, the 5-year actuarial rates of LC, RC, DFS, CSS, and OS were 80, 90, 64, 74, and 74 % respectively. On multivariate analysis, T-stage and multimodality treatment approach correlated significantly with LC. Elective nodal irradiation was given to 42 % of high-risk node-negative patients. None of them developed regional failure. The overall 5-year incidence of grade a parts per thousand yen2 late toxicity was 30 %. Treatment-related blindness was significantly decreased in patients treated with intensity-modulated radiotherapy (IMRT), compared to 2D and 3D-conformal radiotherapy (3DCRT), with organ preservation rates of 86 and 14 % respectively (p = 0.006). We concluded that combined-modality treatment with three, or at least two, modalities resulted in good LC, but with high overall rate of late toxicity. However, the incidence of late toxicity and permanent visual impairment were decreased over time by the introduction of IMRT. Because of the improvement in therapeutic ratio achieved by using IMRT, this highly conformal radiation technique should be the standard of care in patients with SNUC.

Objectives/Hypothesis: To investigate the impact of treatment modality and radiation technique on oncologic outcomes and toxicity of patients with locally advanced oropharyngeal cancer (OPC). Study Design: Retrospective analysis of outcomes and toxicity. Methods: Between 2000 and 2011, 204 consecutive patients with locally advanced OPC were treated with definitive (chemo)radiotherapy using 3-dimensional conformal (3DCRT) or intensity-modulated radiotherapy (IMRT). Endpoints were local control (LC), regional control (RC), disease-free survival (DFS), cause-specific survival (CSS), and overall survival (OS), and toxicity. Results: After a median follow-up of 44 months (range 4–134), the 5-year Kaplan-Meier estimates of LC, RC, DFS, CSS, and OS were 78%, 92%, 60%, 64%, and 48%, respectively. Grade 3 mucositis and dysphagia (feeding-tube dependency) were reported in 75% and 65%, respectively. The overall incidence of grade ≥2 and grade 3 late toxicities were 44% and 16%, respectively. Dysphagia and xerostomia were the most frequently reported late toxicity. Chemotherapy was significantly predictive for improved outcomes and increased toxicity. IMRT was significantly correlated with reduced toxicity. Conclusions: Compared to radiation alone, chemoradiotherapy significantly improved oncologic outcomes, but with significantly increased toxicity. Compared to 3DCRT, the introduction of IMRT resulted in a significant reduction of acute and late toxicity with slightly better, or at least comparable, outcomes. Despite the improvements achieved by the implementation of chemo-IMRT, different new strategies to further improve outcome and reduce toxicity need to be thoroughly investigated in prospective, preferably, randomized trials.

Summary Objectives To compare outcome, toxicity and QoL of two boost modalities for T1-2 oropharyngeal carcinoma (OPC). Materials and methods Between 2000 and 2012, 250 consecutive patients with T1-2N0-3 were treated with 46-Gy of IMRT followed by boost using brachytherapy (BTB) or stereotactic body radiotherapy (CKB). Endpoints were local control (LC), disease-free survival (DFS), overall survival (OS), toxicity and prospective QoL-assessment. Results The 3-year actuarial incidence of LC were 97% and 94% for the CKB and BTB, respectively (p = 0.33). The figures for DFS were 92% and 86% (p = 0.15) and for OS were 81% and 83% (p = 0.82), respectively. The incidence of tube feeding were 17% and 20%, respectively (p = 0.47). The figures for grade ⩾2 late dysphagia were 11% and 8% (p = 0.34) and for xerostomia were 16% and 12% (p = 0.28), respectively. For both modalities, clinically relevant deteriorations were seen on all scales at end of treatment but the scores returned to almost baseline levels within 6–12 months, with exception of QLQ-H&N35-xerostomia. The difference on that scale was neither statistically significant nor clinically relevant between both modalities. Conclusion Comparable outcome, toxicity and QoL-scores were achieved with both modalities. In the light of the logistical hassle around the implantation, the need of dexterity, and the risk of anaesthesia and peri-operative complications associated with BTB, CKB might be regarded as the optimal option to boost early-stage OPC. However, in radiotherapy departments where no facilities are available for stereotactic radiotherapy, BTB is an elegant option to achieve excellent outcome with low toxicity profile and good QoL.

Fluorocarbon polymers are used to enhance thermal stability and electrostatic protection of composite propellant compositions. A precipitation technique has been developed to coat ammonium perchlorate (AP) using a copolymer of hexafluoropropylene and vinylidene fluoride (HFP-VF) with the help of solvent-counter solvent method. The coated AP has been used to prepare propellant compositions in different ratio based on hydroxyl terminated polybutadiene (HTPB), aluminium powder along with uncoated AP and studied for viscosity build-up and visco-elastic behaviour as well as mechanical, ballistic, thermal and sensitivity properties keeping 86% solid loading. The data on viscosity build-up indicate that as the percentage of viton coated AP increases end of mix viscosity and viscosity build-up increase accordingly. The mechanical properties data reveal that tensile strength and percentage elongation are found in increasing order. The burn rate of the composition also increases on higher percentage of HFP-VF coated AP. The thermal stability of composition increases as the percentage of HFP-VF coated AP increases. The data on sensitivity indicate that impact sensitivity decreases on increasing the percentage of HFP-VF coated AP while no change is observed in friction sensitivity value.

Most of the composite propellant compositions contain solid loading up to 86 per cent. The main solid ingredients of composite propellant are ammonium perchlorate (AP) and aluminium powder. Therefore, it is a must to characterise these to improve processibility and quality of composite propellant. Effect of particle size on propellants slurry viscosity and ballistic parameters are well documented, however, the effect of oxidizer particle shape is not reported. In the present study, different methods for size and shape characterisation are discussed and effect of size and shape of AP on composite propellant properties are studied. The data indicate that as size of AP decreases, propellant slurry viscosity increases and burn rate increases. The particles having higher shape factor provides less endof mix (EOM) viscosity of propellant slurry and burn rate. Further, effect of size of ground AP on shape is also investigated. From the data thus obtained, it is inferred that as size of ground AP decreases, shape factor decreases, and particles become more irregular in shape.Defence Science Journal, 2009, 59(3), pp.294-299, DOI:http://dx.doi.org/10.14429/dsj.59.1523