Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D271/00—Heterocyclic compounds containing five-membered rings having two nitrogen atoms and one oxygen atom as the only ring hetero atoms
  • C07D271/02—Heterocyclic compounds containing five-membered rings having two nitrogen atoms and one oxygen atom as the only ring hetero atoms not condensed with other rings
  • C07D271/10—1,3,4-Oxadiazoles; Hydrogenated 1,3,4-oxadiazoles
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D271/00—Heterocyclic compounds containing five-membered rings having two nitrogen atoms and one oxygen atom as the only ring hetero atoms
  • C07D271/02—Heterocyclic compounds containing five-membered rings having two nitrogen atoms and one oxygen atom as the only ring hetero atoms not condensed with other rings
  • C07D271/10—1,3,4-Oxadiazoles; Hydrogenated 1,3,4-oxadiazoles
  • C07D271/107—1,3,4-Oxadiazoles; Hydrogenated 1,3,4-oxadiazoles with two aryl or substituted aryl radicals attached in positions 2 and 5
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K11/00—Luminescent materials, e.g. electroluminescent or chemiluminescent
  • C09K11/06—Luminescent materials, e.g. electroluminescent or chemiluminescent containing organic luminescent materials
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
  • G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
  • G01T1/16—Measuring radiation intensity
  • G01T1/20—Measuring radiation intensity with scintillation detectors
  • G01T1/204—Measuring radiation intensity with scintillation detectors the detector being a liquid
  • G01T1/2042—Composition for liquid scintillation systems

Definitions

• the counts per minute emitted by the material dispersed in the scintillation liquid are measured with a suitable instrument such as a liquid scintillation spectrometer.
• the present invention relates to the use of selected oxdiazole derivatives for scintillation counting methods in atomic disintegrations.
• oxdiazole derivatives comprising the structural element Q i A1 C C LIL-1U. in which A represents an alkyl group which contains 3 to 7 carbon atoms and at least one chain branching, and
• B represents a hydrogen atom, a phenyl group, an alkyl group having 1 to 7 carbon atoms, which may be branched,
• the scintillation liquids concerned are characterized in that they contain as solvent benzene or an alkylbenzene which is liquid at room temperature or a dioxane-l-naphthalene-l-water mixture and 0.01 to 5% by weight (referred to the total weight of thescintillation liquid) of an oxdiazole derivative of the Formula 2.
• oxdiazole derivatives of the formula 11,5 ILA in which B represents a tertiary butyl group or a phenyl group-in liquid scintillation counting methods.
• the scintillation liquids contain preferably toluene as solvent and 0.01 to 5% by weight (referred to the total weight of the scintillation liquid) of an oxdiazole derivative of the Formula 3.
• this invention further includes a method of counting atomic disintegrations ac integrated by the emission of fl-rays, by means of the liquid scintillation method in predominantly aromatic hydrocarbons as scintillator solvents, characterized in that the scintillation liquid used is a solution of an oxidazole of the formula to say as a primary substance activated to emit light by an energy-rich radiation released by an atomic disintegration; these primary substances are combined with the usual secondary solutes, that is to say substances distinguished by an emission of longer wavelength.
• Such suitable secondary solutes are, for example, 1,4-di-[2-(5- phenyloxazolyl)] benzene, 1,4 di [2-(4-methyl-5- phenyloxazolyl)] benzene and 1,4 di (4-isopropylstyryl)-benzenes. Furthermore, they may be combined with neutron capture solutes, gamma conversion solutes, further solvent additives, gels, suspending assistants or solubilizers.
• the counting method used may, of course, be either an internal or an external method.
• Suitable solvents for the liquid scintillation counting method are above all aromatic hydrocarbons that are liquid at room temperature (provided no solvent combination is used) such, for example, as benzene, toluene, a xylene, ethylbenzene, 1,3,5-triethylbenzene, cumene, a cymene, phenylcyclohexane, also ethers such as anisole, dioxane, 1,2-dimethoxyethane; non-aromatic hydrocarbons such as cyclohexane, heptane and the like; or finally solvent mixtures such as toluenef+methanol and possibly water, toluene-i-ethanol, naphthalene+dioxane, naphthalene-l-toluene and possibly water, naphthalenej-l-dioxane +water, 2-methoxyethanol-l-naphthalene+tol
• concentration of the oxdiazole derivatives to be used in the present process may principally vary within wide limits which are defined or restricted by practical considerations. For example in the lower region it must be chosen so that an adequate transmission to the photomultiplier is ensured, whereas the upper region is delineated by the appearance of visible absorption of the selfquenching. Though thus, for example, for the preparation of stock solutions (which are suitably diluted for use) concentrations of 10% or higher are quite acceptable, the working concentrations most suitable for actual practice range approximately from 0.1 to 3%, preferably from 0.4 to 2% (all percentages are by weight, referred to the total weight of the solution).
• preferred solvent systems are the systems toluene+methanl 1:1) with the addition of about 2% of water, 2-methoxyethanol+toluene+naphthalene (40:60:8) with addition of up to 4% of water, dioxane+toluend+naphthalene (40z 60z8) with up to of water, or toluene-1-methanol-l-ethanolamine (50:44:6).
• the composition of the solvent system depends above all on the nature of the substrate or of the isotope to be counted.
• oxdiazoles defined above may be used quite generally wherever the task involved is the transformation of an energy-rich radiation into measurable light.
• the scintillator may be homogeneously dispersed in the polymers concerned (polymerizate, polycondensate or polyadduct) before proceeding to the final shaping operation (casting, drawing, moulding, injection moulding or the like), and the whole is then shaped.
• Crystallization from n-propanol with the aid of active carbon furnishes 240 g. of the compound of the formula EA; ILL-ll in the form of colourless prisms melting at 136 to 137 C.
• EXAMPLE 2 20 ml. of a solution of 5 g. of the compound of the Formula 9 and of the Formula 5 in 1 litre of toluene are introduced into a counter tube, and 0.1 ml. of toluene marked with H having an activity of 0.01 microcurie, is added. At a high-voltage of 1100 volts and a calibration from 100 to 600 there are recorded 6600 c.p.m. for the compound 9 and 5930 c.p.m. for the compound 5.
• EXAMPLE 3 20 ml. each of a solution of 10 g. of the compound of the Formula 9 and of the Formula 5 in 1 litre of toluene are mixed in a counter tube with 1.0 ml. of an ethanolic solution of 1-butyl-3-(para-tolylsulphonyl)-urea marked with The activity added is 0.01 microcurie. The counter tube is then inserted in the counter and the counts per minute are counted. At a high-(voltage of 900 volts and a calibration from 100 to 600 in the measuring channel there are recorded 13,200 c.p.m. for compound 9 and 12,950 c.p.m. for compound 5 EXAMPLE 4 20 ml. of a solution of 10 g.
• EXAMPLE 5 A mixture of 1 g. of 2-[4'-tertiary butylphenyl-'(1')]- S-biphenylyl-l,3,4-oxdiazole of the Formula 9 and 100 g. of vinyltoluene distilled twice under 11 mm. Hg pressure (mixture of the ortho, meta and para isomers) is introduced into a Pyrex glass tube of 25 mm. diameter which is fused at one end. The tube is repeatedly evacuated to a pressure of 0.1 mm. Hg and scavenged with pure nitrogen. Finally, the tube is once more evacuated to 0.1 mm. Hg pressure and the tube is fused at the other end.
• Hg pressure mixture of 1 g. of 2-[4'-tertiary butylphenyl-'(1')]- S-biphenylyl-l,3,4-oxdiazole of the Formula 9 and 100 g. of vinyltoluene distilled twice under 11
• the tube is then heated within 2 hours in a furnace to C. while ensuring by carefully revolving it that the compound of the Formula 9 is completely dissolved.
• To polymerize the batch in the tube it is maintained for 24 hours at 110 C., then heated for 24 hours at C. and for 48 hours at C.
• the following cooling and detensioning phase at 75 C. takes 81 hours.
• the resulting transparent polymer core is recovered by smashing the glass tube.
• To measure the relative count rate the core is turned down to a diameter of 20 mm., sawn up into discs 10 mm. thick, and these discs are polished.
• the measure of the light output is the relative amplitude (RPH) of the counts produced by the Cs conversion electrons. For counting a.
• Philips 5 6 AVP photomultiplier with a ratio 2,2-paraphenylene-bis-(S-phenyloxazole):terphenyl of 1.30 (photomultiplier characteristic) is used.
• the counting standard used is the commercial plastics scintillator NE 102 A (makers Nuclear Enterprises Ltd.) whose RPH value is taken as equal to 1.00.
• the plastics scintillator according to this invention displays an RPH value of 1.10.
• a method of counting atomic disintegration of a radioactive material which is accompanied by an emission of fl-rays, by means of the scintillation counting method which comprises dispersing said material in a scintillation liquid containing from about 0.01% by by weight of an oxdiazole of the formula in which A is an alkyl group which contains 3 to 7 carbon atoms and at least one chain branching; B represents a member selected from the group consisting of a hydrogen atom, a phenyl group, an alkyl group which contains 1 to 7 carbon atoms and a lower alkoxy group, and m is a whole number from 1 to 2, said oxdiazole being dissolved in a solvent selected from the group consisting of benzene, an alkylbenzene that is liquid at room temperature, a methanol+toluene-mixture, a Z-methoxyethanol-i-naphthalene+tolulene mixture and a di0xane+
• oxdiazole is 5,5-di[4-isopropyl phenyl-(1')]-2,2'-bi-1,3,4- oxdiazole.

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• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Spectroscopy & Molecular Physics (AREA)
• General Physics & Mathematics (AREA)
• High Energy & Nuclear Physics (AREA)
• Molecular Biology (AREA)
• Physics & Mathematics (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Health & Medical Sciences (AREA)
• Heterocyclic Carbon Compounds Containing A Hetero Ring Having Nitrogen And Oxygen As The Only Ring Hetero Atoms (AREA)
• Luminescent Compositions (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Applications Claiming Priority (1)

Publications (1)

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ID=4386618

Family Applications (1)

Country Status (7)

Cited By (6)

• 1965
  • 1965-09-15 CH CH1281565A patent/CH460961A/de unknown
• 1966
  • 1966-08-26 GB GB38478/66A patent/GB1164606A/en not_active Expired
  • 1966-08-26 GB GB8587/69A patent/GB1164607A/en not_active Expired
  • 1966-09-06 DE DE19661539807 patent/DE1539807A1/de active Pending
  • 1966-09-06 DE DE1795860A patent/DE1795860C2/de not_active Expired
  • 1966-09-13 SE SE12290/66A patent/SE330791B/xx unknown
  • 1966-09-14 NL NL6612987A patent/NL6612987A/xx unknown
  • 1966-09-14 BE BE686836D patent/BE686836A/xx not_active IP Right Cessation
• 1969
  • 1969-07-31 US US850312A patent/US3650973A/en not_active Expired - Lifetime

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