ABSTRACT
Hepatocellular carcinoma is the third most common cause of cancer-related death. In the past few years, staging systems have been developed that enable patients to be stratified into treatment algorithms in a multidisciplinary setting. Several of these treatments involve minimally invasive image-guided therapy that can be performed by radiologists.
Subject(s)
Carcinoma, Hepatocellular/therapy , Catheter Ablation , Chemoembolization, Therapeutic/methods , Liver Neoplasms/therapy , Algorithms , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/radiotherapy , Carcinoma, Hepatocellular/surgery , Contraindications , Drug Implants , Ethanol/administration & dosage , Ethanol/therapeutic use , Ethiodized Oil/administration & dosage , Ethiodized Oil/therapeutic use , Hepatectomy/methods , Hepatic Artery , Humans , Injections, Intra-Arterial , Liver Neoplasms/drug therapy , Liver Neoplasms/pathology , Liver Neoplasms/radiotherapy , Liver Neoplasms/surgery , Liver Transplantation , Magnetic Resonance Imaging, Interventional , Microspheres , Minimally Invasive Surgical Procedures , Neoplasm Staging , Radiography, Interventional , Randomized Controlled Trials as Topic , Retrospective Studies , Sclerotherapy , Yttrium Radioisotopes/administration & dosage , Yttrium Radioisotopes/therapeutic useABSTRACT
Ammonium nitrate (AN) is an inorganic crystalline compound used as a solid propellant oxidizer and as a nitrogenous fertilizer. The practical use of AN as solid propellant oxidizer is restricted due to the near room temperature polymorphic phase transition and hygroscopicity. A good deal of effort has been expended for last many years to stabilize the polymorphic transitions of AN, so as to minimize the storage difficulties of AN based fertilizers and to achieve more environmentally benign propellant systems. Also, particles with aspect ratio nearer to one are a vital requirement in fertilizer and propellant industries. In the present study AN is crystallized in presence of trace amount of potassium ferrocyanide (K(4)Fe(CN)(6)) crystal habit modifier and kept for different time intervals. And the effect of K(4)Fe(CN)(6) on the habit and phase modification of AN was studied. Phase modified ammonium nitrate (PMAN) with a particle aspect ratio nearer to one was obtained by this method and the reasons for this modifications are discussed. The morphology changes were studied by SEM, the phase modifications were studied by DSC and the structural properties were studied by powder XRD.
Subject(s)
Ferrocyanides/chemistry , Nitrates/chemistry , Calorimetry, Differential Scanning , Crystallization , Microscopy, Electron, Scanning , X-Ray DiffractionABSTRACT
A study has been undertaken on the effect of crystallization method on the IV<-->III transition of ammonium nitrate (AN). AN is crystallized in three different ways, viz. recrystallization, evaporative crystallization and melt crystallization. When the samples were crystallized from saturated aqueous solution, ideal crystals were formed, which behaved differently from the crystals formed from the other methods. The DTA examination of the crystals showed that the crystals have different transition behaviour. The moisture uptake of the samples determined were found to have influenced by the mode of crystallization. The samples were further analyzed by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). The present study showed that the parameters like thermal history, number of previous transformations and moisture content have a very negligible influence on the IV<-->III transition of AN as compared to the method of crystallization.
Subject(s)
Crystallization/methods , Nitrates/chemistry , Phase Transition , Microscopy, Electron, Scanning , Water/chemistry , X-Ray DiffractionABSTRACT
This paper reports the synthesis of three new derivatives of 2,4,5-trinitroimidazole namely, 1-methyl-2,4,5-trinitroimidazole (III), 1-carboethoxy-2,4,5-trinitroimidazole (V) and 1-picryl-2,4,5-trinitroimidazole (VII). The title compounds (III) and (V) were synthesized by the nitration of 1-methyl-/1-carboethoxy-(2,4,5-triiodoimidazole) (II and IV) with fuming nitric acid at 0 degrees C and (VII) was synthesized by condensation of 2,4,5-triiodoimidazole (I) with picryl chloride to obtain 1-picryl-2,4,5-triiodoimidazole (VI) followed by its nitration with fuming nitric acid at 0 degrees C. The synthesized compounds have been characterized by elemental analysis, spectral and thermal techniques. The thermolysis studies using TG-DTA revealed exothermic decomposition of the nitroimidazoles (III, V and VII) with T(max) in the temperature range of 196-225 degrees C. The energy of activation obtained for these compounds was in the range 150-170 kJ/mol. The sensitivity data obtained for the newly synthesized compounds (III, V and VII) indicated their safe nature towards external stimuli (h(50%)>100 cm; friction>36 kg) and could be potential candidates for low vulnerable applications in the futuristic systems. The theoretically predicted performance parameters suggest that 1-methyl-2,4,5-trinitroimidazole (III), exhibits higher velocity of detonation (VOD: 8.8 km/s) compared to compounds V and VII (VOD: 7.6 and 8.41 km/s, respectively).
Subject(s)
Imidazoles/chemical synthesis , Nitro Compounds/chemical synthesis , Nitroimidazoles/chemical synthesis , Calorimetry, Differential Scanning , Energy Transfer , Nitroimidazoles/chemistry , Spectroscopy, Fourier Transform InfraredABSTRACT
Interpenetrating polymer networks of polyurethane and vinyl monomers such as polyacrylamide, polyvinyl pyrrolidone, poly(hydroxyethyl methacrylate) and poly(methyl methacrylate) were implanted intramuscularly in rabbits. Attempts were made to correlate the morphological aspects of the interpenetrating polymer networks to their histological response. A relatively increased hydrophilicity of hydrophobicity of the interpenetrating polymer networks as in the case of polyurethane-polyvinyl pyrrolidone and polyurethane-poly(methyl methacrylate) interpenetrating polymer networks, respectively, could elicit an inert response whilst degradation of materials promoted reactivity.