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A new series of composite propellant compositions, based on ammonium perchlorate,hydroxy-terminated polybutadiene and having metallic fuel as aluminium powder, have beendeveloped. Pressure cast-cum-cured compositions have also been developed with toluenediisocyanate (TDI), isophorone diisocyanate (IPDI), and a mixture of both curatives, i.e., TDIand IPDI, respectively, to study their effect on processibility, mechanical and ballistic propertiesof the compositions. The data indicate that the compositions based on bicurative have a potlife of 7 - 8 h, viscosity build up is from 13280 poise to 14080 poise after 4 h, and the smoothprocessibility of the slurry is enhanced. Further, the mechanical properties are in the range12.2 kg/cm2, 40.2 kg/cm2, and 40.2 per cent for tensile strength, E-modulus and elongation,respectively, and burn rate is almost the same, i.e., 16 ±0.5 mm/s.

Knowledge of variations in Rhizoctonia Solani causing rice sheath blight disease in different geographic regionsis still scarce and may be a useful tool for examining the nature and spread of population, disease epidemiology and host-pathogen interaction within rice patho-system. Molecular markers provide a basis for identifying patterns, dispersal and colonization in spatial and temporal distribution of pathogenic population and in development of species concepts by providing information about the limits of genetically isolated group in relation to patterns of morphological variation and behavior of any pathogen. Twenty-five isolates of Rhizoctonia Solani causing sheath blight in rice were collected from Kerala, New Delhi, Punjab, Uttarakhand and Uttar Pradesh of India and subjected for determination of virulence diversity. There was great diversity in the population of R. Solani which deferred greatly according to color and texture of colony, number and size of sclerotia, time taken for sclerotia formation and also the place and manner of sclerotia formation in the colony. At molecular level, also there was great diversity in the R. Solani population. A total of 80 PCR bands were detected among 25 isolates of R. Solani. The number of alleles per locus, varied from 1to7. Highest [1] PCR products were obtained with primers-OPW-13 and OPA-04 whereas lowest PCR products [2] were obtained with primer UBC-310 and OPB-08. There was only one monomorphic band, which was present in related primer UBC-373.The similarity coefficients among the R. Solani population ranged between 0.53 to 0.94. One isolate of R. Solani from Uttar Pradesh (RS-16) and another isolate from Punjab (RS-1) were most distantly related. The R. Solani isolates (RS-11&RS-12) and (RS-20& RS-21) all belonging to Uttar Pradesh were genetically most closely to each other.

Purpose: To report, from a retrospective analysis of prospectively collected data, on the feasibility, outcome, toxicity, and voice-handicap index (VHI) of patients with T1a glottic cancer treated by a novel intensity modulated radiation therapy technique developed at our institution to treat only the involved vocal cord: single vocal cord irradiation (SVCI). Methods and Materials: Thirty patients with T1a glottic cancer were treated by means of SVCI. Dose prescription was set to 16 x 3.63Gy (total dose 58.08 Gy). The clinical target volume was the entire vocal cord. Setup verification was done by means of an online correction protocol using cone beamcomputed tomography. Data for voice quality assessment were collected prospectively at baseline, end of treatment, and 4, 6, and 12 weeks and 6, 12, and 18 months after treatment using VHI questionnaires. Results: After a median follow-up of 30 months (range, 7-50 months), the 2-year local control and overall survival rates were 100% and 90% because no single local recurrence was reported and 3 patients died because of comorbidity. All patients have completed the intended treatment schedule; no treatment interruptions and no grade 3 acute toxicity were reported. Grade 2 acute dermatitis or dysphagia was reported in only 5 patients (17%). No serious late toxicity was reported; only 1 patient developed temporary grade 2 laryngeal edema, and responded to a short-course of corticosteroid. The VHI improved significantly, from 33.5 at baseline to 9.5 and 10 at 6 weeks and 18 months, respectively (P < .001). The control group, treated to the whole larynx, had comparable local control rates (92.2% vs 100%, P = .24) but more acute toxicity (66% vs 17%, P < .0001) and higher VHI scores (23.8 and 16.7 at 6 weeks and 18 months, respectively, P < .0001). Conclusion: Single vocal cord irradiation is feasible and resulted in maximal local control rate at 2 years. The deterioration in VHI scores was slight and temporary and subsequently improved to normal levels. Long-term follow-up is needed to consolidate these promising results. (C) 2015 Elsevier Inc. All rights reserved.

Ammonium perchlorate has been pulverised by an impact mill (air classifier mill) to study the influence of different operating parameters, viz., effect of mill speed, classifier speed, feed rate, and damper opening (suction rate) on the particle size. Further based on the different grinding parameters, an empirical equation has been developed and used for the prediction of particle size. The experimental results indicate that the values are very close to the predicted ones. In addition, particle size distribution has also been studied by applying different model equations and it has been found that Rosin-Rammler model is the most suitable model for this operation.

Potassium, rubidium, and cesium salts of 5,7-diamino-4,6-dinitrobenzofuroxan (CL-14) have been prepared by reacting sodium salt of 5,7-diamino-4,6-dinitrobenzofuroxan with alkali metal nitrate in an aqueous medium. The structure of the compounds was unequivocally confirmed by spectra data, elemental analyses, and estimation of metal content. Further, the compounds have been evaluated for explosive and thermal properties and found more suitable as compared to alkali metal salts of 4,6-dinitrobenzofuroxan (DNBF).

Chromium, Iron and Copper salts of 4,6-dinitrobenzofuroxan have been prepared by reacting sodium salt of 4,6-dinitrobenzofuroxan with chromium nitrate nonahydrate, ferric nitrate nonahydrate and cupric nitrate trihydrate, respectively. The compounds have been characterized by elemental analysis, spectral data (IR and NMR) and metal content. Some properties including thermal and explosive behaviour of these compounds have been investigated and reported. Further, these molecules have also been investigated in composite propellants as burn-rate modifiers. The preliminary data suggest that iron salt of 4,6-dinitrobenzofuroxan is better than ferric oxide, generally used as a burn-rate modifier for hydroxy-terminated polybutadiene (HTPB) based composite propellants.

Two new initiatory molecules, e.g. rubidium and cesium salts of 4,6-dinitrobenzofuroxan (DNBF) have been prepared by reacting sodium salt of 4,6-dinitrobenzofuroxan (DNBF) with rubidium nitrate and cesium nitrate, respectively, at 60 °C in aqueous medium. The characterisation of compounds by IR, 1 H -NMR, elemental analysis and metal content is described along with some of the evaluated thermal and explosive properties. The results indicate that cesium salt of DNBF (Cs-DNBF) appears promising initiatory and may suitably replace potassium salt of DNBF (K-DNBF), being used currently in initiatory compositions.

7-(1H -1,2,4-triazol-3-amino)-4,6-dinitrobenzofuroxan(TADNB)and 7-(1H-1,2,3,4-tetrazol-5-amino)-4,6-dinitrobenzofuroxan(TeADNBF) have been prepared by condensing 7-chloro-4,6-dinitro benzofuroxan with 3-amino-1,2,4-triazole and 5-amino-1,2, 3,4-tetrazole respectively. The compounds have been characterized by spectral data and elemental analysis. Furthermore, some of the explosive properties of these compounds have also been investigated and reported herein.

Three new derivatives of 4,6-dinitrobenzofuroxan: 7-(4-nitrophenylamino)-4,6-dinitrobenzofuroxan, 7-(3,5-dinitrophenylamino)-4,6-dinitrobenzofuroxan and 7-(2,4,6-trinitrophenylamino)-4,6-dinitrobenzofuroxan, have been synthesised by condensing 4-nitroaniline, 3,5-dinitroaniline and 2,4,6-trinitroaniline with 7-chloro-4,6-dinitrobenzofuroxan, respectively. The characterisation of the compounds by IR, 1H-NMR, mass spectrometry and elemental analysis is described along with some of the evaluated preliminary explosive properties. The compounds were found to exhibit acceptable hazards properties. Furthermore, the thermal stability measurements indicated acceptable stability.

RDX/HMX based Plastic Bonded Explosives (PBXs) with epoxy resin as a binder have been formulated and studied in detail for their explosive, mechanical and thermal properties. The effect of pressure on the moulding powder has also been optimized to achieve maximum loading density and compression strength. Further, these PBXs have been analysed for homogeneity and coating of binder over RDX/HMX crystals. The data suggest that epoxy resin based PBXs have higher loading density, higher mechanical strength and higher velocity of detonation (VOD) as compared to polyurethane based PBXs.

A chemoselective reductive method has been achieved for the preparation of 4-picrylamino-2,6-dinitrotoluene (PADNT), a new insensitive energetic material which has been characterised by spectral data and elemental analysis. Some explosive properties of the compound have also been determined and the results indicate that PANDT is quite safe to impact and friction.

Objectives To evaluate the outcomes of patients with early stage glottic cancer (GC) treated with radiotherapy (RT). Design, setting and participants The current study report on a retrospective analysis of oncologic outcome of 1050 patients with T1-2N0 glottic cancer treated with radiotherapy. Prospective assessment of quality of life (QoL) and voice handicap index (VHI) was performed in all patients treated from 2006 onwards (n = 233). Main outcome measures Local control (LC), regional control (RC), disease-free survival (DFS), overall survival (OS), quality of life and voice handicap index. Results After a median follow-up of 90 months (range 3–309), the actuarial rates of local control, regional control, disease-free survival and overall survival were 85%, 99%, 84% and 81% at 5 years and 82%, 98%, 80% and 61% at 10 years, respectively. On multivariate analysis, T2 tumours, smoking after radiotherapy and conventional radiation scheme correlated significantly with poor local control. Patients who continued smoking after radiotherapy had also significantly lower overall survival rates (OR 4.3, P

The aesthetic result after brachytherapy, especially hypopigmentation, remains a significant problem. Given that brachytherapy may be carcinogenic, it is difficult to recommend this treatment in young patients. For these reasons, there is a need for alternatives to radiation. The purpose of this study was to evaluate the effectiveness of adjuvant photodynamic therapy (PDT) using aminolevulinic acid after keloid excision and to compare it to keloid excision followed by brachytherapy. To assess outcome, the Patient and Observer Scar Assessment Scale (POSAS) was used. Thirty-four patients treated for 45 keloids were evaluated. Twenty-two patients (27 lesions) received brachytherapy and 12 (18 lesions) received PDT. The observers scored a mean POSAS of 19.1 (range 13.0–34.0) for brachytherapy and 24.6 (range 11.0–37.0) for PDT (p = 0.005). The independent observers scored a mean POSAS of 14.6 (range 10.0–20.0) for brachytherapy and 18.6 (range 9.0–42.0) for PDT (p = 0.018). The patients reported a significantly better mean POSAS score after brachytherapy (22.8, range 7.0–53.0) than following PDT (34.2, range 11.0–63.0). The patients’ POSAS score showed no significant difference for the item “general impression” for both treatment groups; the observers scored significantly higher for PDT treatment. The independent observers revealed a higher score for general impression after PDT although not reaching significance. Patients and observers appear to be more satisfied with the results after brachytherapy than PDT. However, patients still have a positive general impression after PDT. Adjunctive aminolevulinic acid–PDT for the treatment of keloids could be used as an alternative for brachytherapy. Level of Evidence: Level IV, therapeutic study.

Dynamic mechanical analysis is a unique technique that measures the modulus and damping of materiais as they are deformed under periodic stress. Propellants, which are viscoelastic in nature, are subjected to time, temperature, and frequency effects during the analysis to determine their dynamic and transient properties. The choice of parameters during the experiments like temperature, frequency, strain (%), and stress level is very crucial to the results obtained since the propellant behaves differently under different conditions. A series of experiments like strain and temperature ramp/ frequency sweeps, creep, stress relaxation, etc. have been conducted using high burning rate composite propellant (burn rate ~20 mm/s at 7,000 kPa), in order to determine the precise effects of such parameters on the results obtained. The evaluated data revealed that as the temperature increases the storage modulus, loss modulus, and tan delta curves with respect to the frequency shift towards the lower side. Moreover, there is equivalency between the increase in the temperature and the decrease in the frequency, which can be used for the time-temperature superposition principles. Further, in transient tests, the relaxation modulus has been found to decrease when increasing strain levels in the given time range. Also, relaxation modulus versus time curves were found to shift towards the lower side with increasing temperature while creep compliance decreases with the increase in stress and decrease in temperature. The glass transition value of the composite propellant increases when there is an increase in the heating rate.

Composite propellant suspensions consist of highly filled polymeric system wherein solid particles of different sizes and shapes are dispersed in a polymeric matrix. The rheological behaviour of a propellant suspension is characterised by viscoplasticity and shear rate and time dependant viscosity. The behaviour of composite propellant suspension has been studied under amplitude sweep test where tests were performed by continuously varying strain amplitude (strain in %, γ) by keeping the frequency and temperature constant and results are plotted in terms of log γ (strain amplitude) vs logGʹ and logGʺ (Storage modulus and loss modulus, respectively). It is clear from amplitude sweep test that dynamic moduli and complex viscosity show marked increase at critical strain amplitude after a plateau region, infering a shear thickening behaviour.

Different compositions have been prepared by incorporating nano sized chromium oxide from 0.25 % to 1 % in HTPB/AP/Al based composite propellant formulation having 86% of solid loading and studied its effect on viscosity build-up, thermal, mechanical and ballistic properties. The findings reveal that on increasing the percentage of nano Cr2O3 in the composition, there is an increase in end of mix viscosity, elastic modulus and tensile strength while elongation decreases accordingly. The data on thermal properties envisage the reduction in thermal decomposition temperature of ammonium perchlorate as well as formulations based on HTPB/AP/Al. The data on ballistic properties reveal that there is an enhancement in burning rate from 6.11 mm/s to 7.88 mm/s at 6.86 MPa, however, marginal increase in pressure exponent (‘n’ values) from 0.35 to 0.53 with 1 wt % of nano Cr2O3 was observed in comparison to reference composition without chromium oxide.

Background To investigate the impact of up-front neck dissection on the outcome of patients with node-positive hypopharyngeal cancer (HPC) treated with (chemo)radiation. Methods Of 135 consecutive patients with node-positive HPC, 32 patients underwent up-front neck dissection followed by (chemo)radiation (group 1), and 103 patients received definitive (chemo)radiation (group 2). Results The 3-year regional, local and distant control for groups 1 and 2 were 92% versus 87% (p = .37), 84% versus 72% (p = .15), and 80% versus 62% (p = .08), respectively. High T classification was the only significant predictor for poor overall survival on multivariate analysis (OR = 3.0, p = .02). Acute and late toxicities and the prospectively assessed quality of life were comparable in both groups. Conclusion Upfront neck dissection followed by (chemo)radiation did not negatively impact on oncologic outcomes, toxicity, or quality of life and therefore is to be regarded as a safe and effective treatment option for small HPC with bulky nodal disease, especially in busy radiation departments with unacceptably long waiting time for definitive (chemo)radiation. © 2012 Wiley Periodicals, Inc. Head Neck, 2013

Objectives/Hypothesis: The main goal of the current study was to comprehensively address the impact of chemoradiation and radiation techniques on toxicity, quality of life (QoL), and functional outcome. Study Design: Retrospective analysis of toxicity and functional outcome and prospective QoL assessment. Methods: From 1996 to 2010, 176 consecutive patients with hypopharyngeal cancer (HPC) were treated with (chemo)radiotherapy. End points were acute and late toxicity, QoL assessment, and functional outcome using laryngoesophageal dysfunction-free survival (LED-FS) defined by the Laryngeal Preservation Consensus Panel. Results: Chemoradiation significantly increased grade 3 acute toxicity compared to radiotherapy alone (71% vs. 55%, P = .02). The 3-year grade ≥2 late toxicity was 32%. Intensity-modulated radiotherapy (IMRT) significantly reduced late toxicity compared to three-dimensional conformal radiotherapy (3DCRT) (24% vs. 44%, P = .007). Slight deterioration in QoL scores was observed on almost all scales, and was more pronounced in patients treated with chemoradiation, albeit not statistically significant except for xerostomia. Chemoradiation, compared to radiotherapy alone, improved LED-FS at 3 years (51% vs. 24% for the entire group and 83% vs. 63% for the 78 living patients at last follow-up, respectively [P = .05]). Conclusions: Compared to radiotherapy alone, chemoradiation significantly improved functional outcome, increased acute toxicity, but without significant increase in late radiation-induced side effects. Statistically significant deterioration in QoL scores was reported only for xerostomia. IMRT, compared to 3DCRT, reduced the incidence and severity of acute and late toxicity, thereby broadening the therapeutic window, and may allow dose escalation for further improvement of outcomes of laryngeal preservation protocols.

1,3-Bis(1,2,4-triazol-3-amino)-2,4,6-trinitrobenzene (BTATNB) has been synthesized by condensing 1,3-dichloro-2,4,6-trinitrobenzene and 3-amino-1,2,4-triazole in dimethyl formamide (DMF) at 125±2°C. The product has been characterized by elemental analysis, Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR) and mass spectrometry. The data on thermal and explosive properties indicate that BTATNB is slightly more thermally stable than 3-picrylamino-1,2,4-triazole (PATO). At the same time, it is safer towards impact and friction.

Different composite propellant mixtures have been prepared using ammonium perchlorate, aluminium powder and hydroxyl terminated polybutadiene by varying the percentage of plasticiser and addition of toluene diisocyanate at different temperatures, and studied their different properties such as viscosity build-up, mechanical and ballistic properties and sensitivity. The data on different plasticiser level indicate that on decreasing the plasticiser content, there is a significant enhancement in end of mix viscosity, tensile strength and modulus while elongation decreases drastically. The data on sensitivity of the studied mixtures reveal that on decreasing the percentage of plasticiser, the sensitivity increases, accordingly. Further, the data on the effect of addition of TDI at different temperatures (35-60 degrees C) infer that on increasing the addition temperature of TDI there is a decrease in end of mix viscosity i.e. 800Pas at 35 degrees C to 448Pas at 60 degrees C. Moreover, there is no effect on mechanical and ballistic properties on higher temperature addition of TDI was observed.

5,7-Diamino-4,6-dinitrobenzofuroxan (CL-14) has been synthesized by a cost-effective method. CL-14 was characterized by spectral data (IR, NMR and mass) and elemental analysis. The compound was evaluated in plastic bonded explosives (PBX) using polyurethane (PU) as binder. The thermal, mechanical and explosive properties of PBX composition from preliminary tests are also reported. Good thermal stability as well as good insensitiveness are indicated.