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S N Asthana - One of the best experts on this subject based on the ideXlab platform.
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energetic co ordination compounds synthesis characterization and thermolysis studies on bis 5 nitro 2h tetrazolato n2 tetraammine cobalt iii perchlorate bncp and its new transition metal ni cu zn perchlorate analogues
Journal of Hazardous Materials, 2005Co-Authors: M B Talawar, A P Agrawal, S N AsthanaAbstract:Abstract Bis-(5-nitro-2H-tetrazolato-N2)tetraammine[cobalt(III)/nickel(III)] perchlorates (BNCP/BNNP) and mono-(5-nitro-H-tetrazolato-N)triammine [copper(II)/zinc(II)] perchlorates (MNCup/MNZnP) have been synthesized during this work. The synthesis was carried out by addition of carbonato tetraammine metal [Co/Ni/Cu/Zn] nitrate [CTCN/CTNN/CTCuN/CTZnN] to the aqueous solution of sodium salt of 5-nitrotetrazole followed by reaction with perchloric acid. The precursors were synthesized by the reaction of aqueous solution of their respective nitrates with ammonium carbonate at 70 °C. The complexes and their precursors were characterized by determining metal and perchlorate content as well as infrared (IR), electron spectra for chemical analysis (ESCA) and X-ray diffraction (XRD) techniques. The TG profiles indicated that BNCP, BNNP and MNCup are thermally stable up to the temperature of 260–278 °C unlike MNZnP (150 °C). Sudden exothermic decomposition was observed in case of bis-(5-nitro-2H-tetrazolato-N2)tetraammine cobalt(III) perchlorate, bis-(5-nitro-2H-tetrazolato-N2)tetraammine nickel(III) perchlorate and mono-(5-nitro-H-tetrazolato-N)triammine zinc(II) perchlorate resulting in the severe damage of the Sample Cup. Sensitivity data indicated that the Co/Ni/Cu complexes are more friction sensitive (3–4.8 kg) than mono-(5-nitro-H-tetrazolato-N)triammine zinc(II) perchlorate (14 kg). The impact sensitivity results of the complexes corresponded to h50% of 30–36 cm.
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energetic co ordination compounds synthesis characterization and thermolysis studies on bis 5 nitro 2h tetrazolato n2 tetraammine cobalt iii perchlorate bncp and its new transition metal ni cu zn perchlorate analogues
Journal of Hazardous Materials, 2005Co-Authors: M B Talawar, A P Agrawal, S N AsthanaAbstract:Bis-(5-nitro-2H-tetrazolato-N2)tetraammine[cobalt(III)/nickel(III)] perchlorates (BNCP/BNNP) and mono-(5-nitro-H-tetrazolato-N)triammine [copper(II)/zinc(II)] perchlorates (MNCup/MNZnP) have been synthesized during this work. The synthesis was carried out by addition of carbonato tetraammine metal [Co/Ni/Cu/Zn] nitrate [CTCN/CTNN/CTCuN/CTZnN] to the aqueous solution of sodium salt of 5-nitrotetrazole followed by reaction with perchloric acid. The precursors were synthesized by the reaction of aqueous solution of their respective nitrates with ammonium carbonate at 70 degrees C. The complexes and their precursors were characterized by determining metal and perchlorate content as well as infrared (IR), electron spectra for chemical analysis (ESCA) and X-ray diffraction (XRD) techniques. The TG profiles indicated that BNCP, BNNP and MNCup are thermally stable up to the temperature of 260-278 degrees C unlike MNZnP (150 degrees C). Sudden exothermic decomposition was observed in case of bis-(5-nitro-2H-tetrazolato-N2)tetraammine cobalt(III) perchlorate, bis-(5-nitro-2H-tetrazolato-N2)tetraammine nickel(III) perchlorate and mono-(5-nitro-H-tetrazolato-N)triammine zinc(II) perchlorate resulting in the severe damage of the Sample Cup. Sensitivity data indicated that the Co/Ni/Cu complexes are more friction sensitive (3-4.8 kg) than mono-(5-nitro-H-tetrazolato-N)triammine zinc(II) perchlorate (14 kg). The impact sensitivity results of the complexes corresponded to h50% of 30-36 cm.
M B Talawar - One of the best experts on this subject based on the ideXlab platform.
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energetic co ordination compounds synthesis characterization and thermolysis studies on bis 5 nitro 2h tetrazolato n2 tetraammine cobalt iii perchlorate bncp and its new transition metal ni cu zn perchlorate analogues
Journal of Hazardous Materials, 2005Co-Authors: M B Talawar, A P Agrawal, S N AsthanaAbstract:Abstract Bis-(5-nitro-2H-tetrazolato-N2)tetraammine[cobalt(III)/nickel(III)] perchlorates (BNCP/BNNP) and mono-(5-nitro-H-tetrazolato-N)triammine [copper(II)/zinc(II)] perchlorates (MNCup/MNZnP) have been synthesized during this work. The synthesis was carried out by addition of carbonato tetraammine metal [Co/Ni/Cu/Zn] nitrate [CTCN/CTNN/CTCuN/CTZnN] to the aqueous solution of sodium salt of 5-nitrotetrazole followed by reaction with perchloric acid. The precursors were synthesized by the reaction of aqueous solution of their respective nitrates with ammonium carbonate at 70 °C. The complexes and their precursors were characterized by determining metal and perchlorate content as well as infrared (IR), electron spectra for chemical analysis (ESCA) and X-ray diffraction (XRD) techniques. The TG profiles indicated that BNCP, BNNP and MNCup are thermally stable up to the temperature of 260–278 °C unlike MNZnP (150 °C). Sudden exothermic decomposition was observed in case of bis-(5-nitro-2H-tetrazolato-N2)tetraammine cobalt(III) perchlorate, bis-(5-nitro-2H-tetrazolato-N2)tetraammine nickel(III) perchlorate and mono-(5-nitro-H-tetrazolato-N)triammine zinc(II) perchlorate resulting in the severe damage of the Sample Cup. Sensitivity data indicated that the Co/Ni/Cu complexes are more friction sensitive (3–4.8 kg) than mono-(5-nitro-H-tetrazolato-N)triammine zinc(II) perchlorate (14 kg). The impact sensitivity results of the complexes corresponded to h50% of 30–36 cm.
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energetic co ordination compounds synthesis characterization and thermolysis studies on bis 5 nitro 2h tetrazolato n2 tetraammine cobalt iii perchlorate bncp and its new transition metal ni cu zn perchlorate analogues
Journal of Hazardous Materials, 2005Co-Authors: M B Talawar, A P Agrawal, S N AsthanaAbstract:Bis-(5-nitro-2H-tetrazolato-N2)tetraammine[cobalt(III)/nickel(III)] perchlorates (BNCP/BNNP) and mono-(5-nitro-H-tetrazolato-N)triammine [copper(II)/zinc(II)] perchlorates (MNCup/MNZnP) have been synthesized during this work. The synthesis was carried out by addition of carbonato tetraammine metal [Co/Ni/Cu/Zn] nitrate [CTCN/CTNN/CTCuN/CTZnN] to the aqueous solution of sodium salt of 5-nitrotetrazole followed by reaction with perchloric acid. The precursors were synthesized by the reaction of aqueous solution of their respective nitrates with ammonium carbonate at 70 degrees C. The complexes and their precursors were characterized by determining metal and perchlorate content as well as infrared (IR), electron spectra for chemical analysis (ESCA) and X-ray diffraction (XRD) techniques. The TG profiles indicated that BNCP, BNNP and MNCup are thermally stable up to the temperature of 260-278 degrees C unlike MNZnP (150 degrees C). Sudden exothermic decomposition was observed in case of bis-(5-nitro-2H-tetrazolato-N2)tetraammine cobalt(III) perchlorate, bis-(5-nitro-2H-tetrazolato-N2)tetraammine nickel(III) perchlorate and mono-(5-nitro-H-tetrazolato-N)triammine zinc(II) perchlorate resulting in the severe damage of the Sample Cup. Sensitivity data indicated that the Co/Ni/Cu complexes are more friction sensitive (3-4.8 kg) than mono-(5-nitro-H-tetrazolato-N)triammine zinc(II) perchlorate (14 kg). The impact sensitivity results of the complexes corresponded to h50% of 30-36 cm.
A P Agrawal - One of the best experts on this subject based on the ideXlab platform.
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energetic co ordination compounds synthesis characterization and thermolysis studies on bis 5 nitro 2h tetrazolato n2 tetraammine cobalt iii perchlorate bncp and its new transition metal ni cu zn perchlorate analogues
Journal of Hazardous Materials, 2005Co-Authors: M B Talawar, A P Agrawal, S N AsthanaAbstract:Abstract Bis-(5-nitro-2H-tetrazolato-N2)tetraammine[cobalt(III)/nickel(III)] perchlorates (BNCP/BNNP) and mono-(5-nitro-H-tetrazolato-N)triammine [copper(II)/zinc(II)] perchlorates (MNCup/MNZnP) have been synthesized during this work. The synthesis was carried out by addition of carbonato tetraammine metal [Co/Ni/Cu/Zn] nitrate [CTCN/CTNN/CTCuN/CTZnN] to the aqueous solution of sodium salt of 5-nitrotetrazole followed by reaction with perchloric acid. The precursors were synthesized by the reaction of aqueous solution of their respective nitrates with ammonium carbonate at 70 °C. The complexes and their precursors were characterized by determining metal and perchlorate content as well as infrared (IR), electron spectra for chemical analysis (ESCA) and X-ray diffraction (XRD) techniques. The TG profiles indicated that BNCP, BNNP and MNCup are thermally stable up to the temperature of 260–278 °C unlike MNZnP (150 °C). Sudden exothermic decomposition was observed in case of bis-(5-nitro-2H-tetrazolato-N2)tetraammine cobalt(III) perchlorate, bis-(5-nitro-2H-tetrazolato-N2)tetraammine nickel(III) perchlorate and mono-(5-nitro-H-tetrazolato-N)triammine zinc(II) perchlorate resulting in the severe damage of the Sample Cup. Sensitivity data indicated that the Co/Ni/Cu complexes are more friction sensitive (3–4.8 kg) than mono-(5-nitro-H-tetrazolato-N)triammine zinc(II) perchlorate (14 kg). The impact sensitivity results of the complexes corresponded to h50% of 30–36 cm.
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energetic co ordination compounds synthesis characterization and thermolysis studies on bis 5 nitro 2h tetrazolato n2 tetraammine cobalt iii perchlorate bncp and its new transition metal ni cu zn perchlorate analogues
Journal of Hazardous Materials, 2005Co-Authors: M B Talawar, A P Agrawal, S N AsthanaAbstract:Bis-(5-nitro-2H-tetrazolato-N2)tetraammine[cobalt(III)/nickel(III)] perchlorates (BNCP/BNNP) and mono-(5-nitro-H-tetrazolato-N)triammine [copper(II)/zinc(II)] perchlorates (MNCup/MNZnP) have been synthesized during this work. The synthesis was carried out by addition of carbonato tetraammine metal [Co/Ni/Cu/Zn] nitrate [CTCN/CTNN/CTCuN/CTZnN] to the aqueous solution of sodium salt of 5-nitrotetrazole followed by reaction with perchloric acid. The precursors were synthesized by the reaction of aqueous solution of their respective nitrates with ammonium carbonate at 70 degrees C. The complexes and their precursors were characterized by determining metal and perchlorate content as well as infrared (IR), electron spectra for chemical analysis (ESCA) and X-ray diffraction (XRD) techniques. The TG profiles indicated that BNCP, BNNP and MNCup are thermally stable up to the temperature of 260-278 degrees C unlike MNZnP (150 degrees C). Sudden exothermic decomposition was observed in case of bis-(5-nitro-2H-tetrazolato-N2)tetraammine cobalt(III) perchlorate, bis-(5-nitro-2H-tetrazolato-N2)tetraammine nickel(III) perchlorate and mono-(5-nitro-H-tetrazolato-N)triammine zinc(II) perchlorate resulting in the severe damage of the Sample Cup. Sensitivity data indicated that the Co/Ni/Cu complexes are more friction sensitive (3-4.8 kg) than mono-(5-nitro-H-tetrazolato-N)triammine zinc(II) perchlorate (14 kg). The impact sensitivity results of the complexes corresponded to h50% of 30-36 cm.
Chuichi Watanabe - One of the best experts on this subject based on the ideXlab platform.
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polymer coated Sample Cup for quantitative analysis of semi volatile phthalates in polymeric materials by thermal desorption gas chromatography mass spectrometry
Journal of Chromatography A, 2015Co-Authors: Akihiko Hosaka, Chuichi Watanabe, Atsushi Watanabe, Norio Teramae, Hajime OhtaniAbstract:A new "polymer-coated" Sample Cup useful for the analysis of phthalates in polymeric materials by thermal desorption (TD)-GC/MS using a temperature programmable furnace type pyrolyzer as a TD device was developed to suppress the emission of semi-volatile phthalates such as dimethyl phthalate (DMP) and diethyl phthalate (DEP) during the measurements. The inner surface of a Sample Cup was coated by polymers which act as a sorbent for the phthalates. Three polymers, polyvinyl chloride, polystyrene and poly (methyl methacrylate), were chosen as the coating polymers. A mixture of ten phthalates including DMP and DEP was used as the test Sample to estimate the performance of the Sample Cups. When a conventional Sample Cup without any polymer coating was used, 90 and 50% reductions in the peak areas of DMP and DEP were respectively observed at the waiting time of 200 min. On the contrary, no reduction of peak area of DMP and DEP during the same waiting time was observed with any one of the three coating polymers at the proper polymer film thickness. These results suggest that the polymer-coated Sample Cup suppresses the emission of semi-volatile phthalates and is effective for the analysis of phthalates containing DMP and DEP by TD-GC/MS.
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Development of a new flow-through Sample Cup for the vertical micro-furnace pyrolyzer to reduce undesirable secondary reactions and band broadening of resulting pyrolyzates
Journal of Analytical and Applied Pyrolysis, 2007Co-Authors: Akihiko Hosaka, Chuichi Watanabe, Shin TsugeAbstract:Abstract When a vertical micro-furnace pyrolyzer is adopted for pyrolysis-gas chromatography (Py-GC), the Sample is usually introduced into the center of the preheated pyrolysis chamber by mounting it in a small cylindrical Sample Cup with a dead-end bottom having a volume of a few dozens micro liters which in some case might be responsible for a stagnant flow of carrier gas in the pyrolysis chamber to cause undesirable secondary reactions of the resulting pyrolyzates and/or peak broadening phenomenon. In order to quench the dead-end flow, a new “flow-through” Sample Cup in which a small hole (ca. 1.0 mm i.d.) was drilled through its bottom was developed, and its basic characteristics were first examined by measuring the pyrogram of polycarbonate (PC) at 600 °C under different carrier gas flow rates. Various secondary products such as phenol and p -isopropenyl phenol derived from bisphenol A, the main pyrolyzatate of PC were observed when the conventional Sample Cup without the hole was used under a relatively lower flow rate as 25 ml/min. However, they were markedly decreased when the “flow-through” Sample Cup was used. Furthermore, the resolution of the lower boiling point pyrolyzates (C 1 –C 8 ) from high density polyethylene (HDPE) was also much improved by use of the “flow-through” Sample Cup.
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Pyrolysis-gas chromatography for end group analysis of polystyrene macromonomers using stepwise pyrolysis combined with on-line methylation
Journal of Analytical and Applied Pyrolysis, 1993Co-Authors: Hajime Ohtani, Shohji Ueda, Yasuhisa Tsukahara, Chuichi WatanabeAbstract:Abstract The end group functionalities of polystyrene macromonomers with methacryloyl (ML) end groups were determined by stepwise pyrolysis-gas chromatography (PyGC) at different temperatures, using a two stage pyrolyser consisting of two independent furnaces, combined with an on-line methylation technique. The macromonomer Sample in THF solution was mixed with tetramethylammonium hydroxide in methanol solution, as the methylation reagent, in a Sample Cup; this was introduced into the first furnace (250°C) of the pyrolyser attached to a gas chromatograph to decompose selectively the ML end group moieties in the macromonomer to methyl methacrylate (MMA). After GC analysis of the formed MMA, the Sample Cup was dropped down into the second furnace (650°C) to pyrolyse the residual polystyrene main chain thoroughly. The concentration of the ML end groups was determined by comparing the peak intensity of MMA observed in the former pyrogram with those of the characteristic products formed from the polystyrene main chain in the latter pyrogram. The end group functionalities of several macromonomer Samples calculated from the concentrations of the end groups, determined by PyGC, were in fairly good agreement with those determined by 1 H NMR, and with those calculated from the data of the maximum conversion of the macromonomers.
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development of a new pyrolyzer for thermal desorption and or pyrolysis gas chromatography of polymeric materials
Hrc-journal of High Resolution Chromatography, 1991Co-Authors: Chuichi Watanabe, Shin Tsuge, Kuniko Teraishi, Hajime Ohtani, Keiji HashimotoAbstract:A new vertical microfurnace-type pyrolyzer for thermal desorption and/or pyrolysis-gas chromatography has been developed. The pyrolyzer consists of two independent temperature-controlled ovens. Initially, in the desorption process, a Sample Cup containing the polymeric Sample of interest is inserted into an oven at 300°C; the Sample is then re-positioned at the upper part of the pyrolyzer where the temperature is maintained at room temperature. The resulting vaporized components such as residual solvents and additives give a desorption chromatogram. The relative peak intensities of desorbed plasticizers in acrylonitrile butadiene-rubber gave a relative standard deviation (RSD) of less than 2%. Subsequently, pyrolysis of the remaining polymer is conducted by dropping the Sample Cup into the second, pyrolyzing, oven at 55°C; at this stage the pyrogram is recorded. The resulting two chromatograms of desorbed components and pyrolysis products make it easier to characterize the polymer formulation than the complicated pyrogram obtained by an ordinary, single-step pyrolysis.
Hajime Ohtani - One of the best experts on this subject based on the ideXlab platform.
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polymer coated Sample Cup for quantitative analysis of semi volatile phthalates in polymeric materials by thermal desorption gas chromatography mass spectrometry
Journal of Chromatography A, 2015Co-Authors: Akihiko Hosaka, Chuichi Watanabe, Atsushi Watanabe, Norio Teramae, Hajime OhtaniAbstract:A new "polymer-coated" Sample Cup useful for the analysis of phthalates in polymeric materials by thermal desorption (TD)-GC/MS using a temperature programmable furnace type pyrolyzer as a TD device was developed to suppress the emission of semi-volatile phthalates such as dimethyl phthalate (DMP) and diethyl phthalate (DEP) during the measurements. The inner surface of a Sample Cup was coated by polymers which act as a sorbent for the phthalates. Three polymers, polyvinyl chloride, polystyrene and poly (methyl methacrylate), were chosen as the coating polymers. A mixture of ten phthalates including DMP and DEP was used as the test Sample to estimate the performance of the Sample Cups. When a conventional Sample Cup without any polymer coating was used, 90 and 50% reductions in the peak areas of DMP and DEP were respectively observed at the waiting time of 200 min. On the contrary, no reduction of peak area of DMP and DEP during the same waiting time was observed with any one of the three coating polymers at the proper polymer film thickness. These results suggest that the polymer-coated Sample Cup suppresses the emission of semi-volatile phthalates and is effective for the analysis of phthalates containing DMP and DEP by TD-GC/MS.
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Pyrolysis-gas chromatography for end group analysis of polystyrene macromonomers using stepwise pyrolysis combined with on-line methylation
Journal of Analytical and Applied Pyrolysis, 1993Co-Authors: Hajime Ohtani, Shohji Ueda, Yasuhisa Tsukahara, Chuichi WatanabeAbstract:Abstract The end group functionalities of polystyrene macromonomers with methacryloyl (ML) end groups were determined by stepwise pyrolysis-gas chromatography (PyGC) at different temperatures, using a two stage pyrolyser consisting of two independent furnaces, combined with an on-line methylation technique. The macromonomer Sample in THF solution was mixed with tetramethylammonium hydroxide in methanol solution, as the methylation reagent, in a Sample Cup; this was introduced into the first furnace (250°C) of the pyrolyser attached to a gas chromatograph to decompose selectively the ML end group moieties in the macromonomer to methyl methacrylate (MMA). After GC analysis of the formed MMA, the Sample Cup was dropped down into the second furnace (650°C) to pyrolyse the residual polystyrene main chain thoroughly. The concentration of the ML end groups was determined by comparing the peak intensity of MMA observed in the former pyrogram with those of the characteristic products formed from the polystyrene main chain in the latter pyrogram. The end group functionalities of several macromonomer Samples calculated from the concentrations of the end groups, determined by PyGC, were in fairly good agreement with those determined by 1 H NMR, and with those calculated from the data of the maximum conversion of the macromonomers.
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development of a new pyrolyzer for thermal desorption and or pyrolysis gas chromatography of polymeric materials
Hrc-journal of High Resolution Chromatography, 1991Co-Authors: Chuichi Watanabe, Shin Tsuge, Kuniko Teraishi, Hajime Ohtani, Keiji HashimotoAbstract:A new vertical microfurnace-type pyrolyzer for thermal desorption and/or pyrolysis-gas chromatography has been developed. The pyrolyzer consists of two independent temperature-controlled ovens. Initially, in the desorption process, a Sample Cup containing the polymeric Sample of interest is inserted into an oven at 300°C; the Sample is then re-positioned at the upper part of the pyrolyzer where the temperature is maintained at room temperature. The resulting vaporized components such as residual solvents and additives give a desorption chromatogram. The relative peak intensities of desorbed plasticizers in acrylonitrile butadiene-rubber gave a relative standard deviation (RSD) of less than 2%. Subsequently, pyrolysis of the remaining polymer is conducted by dropping the Sample Cup into the second, pyrolyzing, oven at 55°C; at this stage the pyrogram is recorded. The resulting two chromatograms of desorbed components and pyrolysis products make it easier to characterize the polymer formulation than the complicated pyrogram obtained by an ordinary, single-step pyrolysis.
