The dissociation of hydrogen atoms from the methylene group of cyclopentadiene (CP) and indene (I... more The dissociation of hydrogen atoms from the methylene group of cyclopentadiene (CP) and indene (ID) excited with a 193 nm photon has been studied by hydrogen atom laser induced fluorescence. The rate of dissociation of IND was 7.4×106 s−1 but that of CP was too fast to measure. The ratio of H atoms to D atoms generated from 5-deuteriocyclopentadiene (5-dCP) was 3.91±0.46. Rice–Ramsberger–Kassel–Marcus theory was used to calculate the rates of dissociation of CP and 5-dCP. The quantum yield for dissociating H atoms from CP was 0.85±0.07. The ejected H atoms have a Maxwell velocity distribution with temperatures which are equal to the vibrational temperatures, 3690 and 2479 K for CP and IND, respectively. The most important result of the work is this confirmation of an earlier finding on a different set of molecules that the translational temperature of the fragments after the dissociation is equal to the vibrational temperature before the dissociation. This is explained by the assumption that the motion of the fast, light hydrogen atom is partly decoupled from that of the heavier, slower atoms.
PURPOSE: To provide a solvent system contg. methoxy acetone and water, low in viscosity, excellen... more PURPOSE: To provide a solvent system contg. methoxy acetone and water, low in viscosity, excellent in treatability and solubility and suitable as a solvent for a curing agent for an epoxy resin or the like. CONSTITUTION: This solvent system contains (A) methoxy acetone and (B) water, preferably by 9 to 15 wt.% and, more preferably (C) an oxygen-contg. organic solvent other than methoxy acetone such as propylene glycol, diether or the like. Furthermore, the solvent system is preferably used as solvents for a curing agent such as dicyandiamide for an epoxy resin, for a curing catalyst such as imidazole and for a cure inhibitor such as boric acid. COPYRIGHT: (C)1994,JPO
The paper discusses polyurethane foams which reduce structural borne and air borne noise to provi... more The paper discusses polyurethane foams which reduce structural borne and air borne noise to provide driving comfort.
PURPOSE: To obtain the title solvent solution useful for dissolving a curing agent, a curing cata... more PURPOSE: To obtain the title solvent solution useful for dissolving a curing agent, a curing catalyst, a cure inhibitor for epoxy resins or a blend thereof which is a water-free solvent system containing methoxy acetone and an organic protic solvent. CONSTITUTION: This solvent solution comprises a water-free solvent system containing (A) preferably 25-90 (wt.)%, more preferably 30-65% of methoxy acetone, based on the total weight of the solvent system and (B) 5-75%, preferably 10-70%, more preferably 10-60% of an organic protic solvent (preferably methanol, ethanol, ethylene glycol, propylene glycol or the like) and one or more (i) a curing agent for epoxy resins (preferably dicyandiamide), (ii) a curing catalyst (e.g.; imidazole or the like) and (iii) a cure inhibitor (e.g.; boric acid or the like). COPYRIGHT: (C)1995,JPO
The [C4H70]+ ions [CH2CHC(OH)CH3]+ (1), [CH3CHCHC(OH)H]+ (2), [CH2C(CH3)C(OH)H]+ (3), [Ch3CH2CH2C... more The [C4H70]+ ions [CH2CHC(OH)CH3]+ (1), [CH3CHCHC(OH)H]+ (2), [CH2C(CH3)C(OH)H]+ (3), [Ch3CH2CH2CO]+ (4) and [(CH3)2CHCO]+ (5) have been characterized by their collision-induced dissociation (CID) mass spectra and charge stripping mass spectra. The ions 1–3 were prepared by gas phase protonation of the relevant carbonyl compounds while 4 and 5 were prepared by dissociative electron impact ionization of the appropriate carbonyl compounds. Only 2 and 3 give similar spectra and are difficult to distinguish from each other; the remaining ions can be readily characterized by either their CID mass spectra or their charge stripping mass spectra. The 2-pentanone molecular ion fragments by loss of the C(1) methyl and the C(5) methyl in the ratio 60:40 for metastable ions; at higher internal energies loss of the C(1) methyl becomes more favoured. Metastable ion characteristics, CID mass spectra and charge stripping mass spectra all show that loss of the C(1) methyl leads to formation of the a...
The dissociation of hydrogen atoms from the methylene group of cyclopentadiene (CP) and indene (I... more The dissociation of hydrogen atoms from the methylene group of cyclopentadiene (CP) and indene (ID) excited with a 193 nm photon has been studied by hydrogen atom laser induced fluorescence. The rate of dissociation of IND was 7.4×106 s−1 but that of CP was too fast to measure. The ratio of H atoms to D atoms generated from 5-deuteriocyclopentadiene (5-dCP) was 3.91±0.46. Rice–Ramsberger–Kassel–Marcus theory was used to calculate the rates of dissociation of CP and 5-dCP. The quantum yield for dissociating H atoms from CP was 0.85±0.07. The ejected H atoms have a Maxwell velocity distribution with temperatures which are equal to the vibrational temperatures, 3690 and 2479 K for CP and IND, respectively. The most important result of the work is this confirmation of an earlier finding on a different set of molecules that the translational temperature of the fragments after the dissociation is equal to the vibrational temperature before the dissociation. This is explained by the assumption that the motion of the fast, light hydrogen atom is partly decoupled from that of the heavier, slower atoms.
PURPOSE: To provide a solvent system contg. methoxy acetone and water, low in viscosity, excellen... more PURPOSE: To provide a solvent system contg. methoxy acetone and water, low in viscosity, excellent in treatability and solubility and suitable as a solvent for a curing agent for an epoxy resin or the like. CONSTITUTION: This solvent system contains (A) methoxy acetone and (B) water, preferably by 9 to 15 wt.% and, more preferably (C) an oxygen-contg. organic solvent other than methoxy acetone such as propylene glycol, diether or the like. Furthermore, the solvent system is preferably used as solvents for a curing agent such as dicyandiamide for an epoxy resin, for a curing catalyst such as imidazole and for a cure inhibitor such as boric acid. COPYRIGHT: (C)1994,JPO
The paper discusses polyurethane foams which reduce structural borne and air borne noise to provi... more The paper discusses polyurethane foams which reduce structural borne and air borne noise to provide driving comfort.
PURPOSE: To obtain the title solvent solution useful for dissolving a curing agent, a curing cata... more PURPOSE: To obtain the title solvent solution useful for dissolving a curing agent, a curing catalyst, a cure inhibitor for epoxy resins or a blend thereof which is a water-free solvent system containing methoxy acetone and an organic protic solvent. CONSTITUTION: This solvent solution comprises a water-free solvent system containing (A) preferably 25-90 (wt.)%, more preferably 30-65% of methoxy acetone, based on the total weight of the solvent system and (B) 5-75%, preferably 10-70%, more preferably 10-60% of an organic protic solvent (preferably methanol, ethanol, ethylene glycol, propylene glycol or the like) and one or more (i) a curing agent for epoxy resins (preferably dicyandiamide), (ii) a curing catalyst (e.g.; imidazole or the like) and (iii) a cure inhibitor (e.g.; boric acid or the like). COPYRIGHT: (C)1995,JPO
The [C4H70]+ ions [CH2CHC(OH)CH3]+ (1), [CH3CHCHC(OH)H]+ (2), [CH2C(CH3)C(OH)H]+ (3), [Ch3CH2CH2C... more The [C4H70]+ ions [CH2CHC(OH)CH3]+ (1), [CH3CHCHC(OH)H]+ (2), [CH2C(CH3)C(OH)H]+ (3), [Ch3CH2CH2CO]+ (4) and [(CH3)2CHCO]+ (5) have been characterized by their collision-induced dissociation (CID) mass spectra and charge stripping mass spectra. The ions 1–3 were prepared by gas phase protonation of the relevant carbonyl compounds while 4 and 5 were prepared by dissociative electron impact ionization of the appropriate carbonyl compounds. Only 2 and 3 give similar spectra and are difficult to distinguish from each other; the remaining ions can be readily characterized by either their CID mass spectra or their charge stripping mass spectra. The 2-pentanone molecular ion fragments by loss of the C(1) methyl and the C(5) methyl in the ratio 60:40 for metastable ions; at higher internal energies loss of the C(1) methyl becomes more favoured. Metastable ion characteristics, CID mass spectra and charge stripping mass spectra all show that loss of the C(1) methyl leads to formation of the a...
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