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Dados de pesquisa: contribuição para o estabelecimento de um modelo de curadoria digital para o país
No full textCiberinfraestrutura para integração, acesso, compartilhamento e reuso de dados de pesquisa da área nuclear
No full textVisualization of in vitro evaluation of restored Teeth with synthetic resins by neutron radiography
No full textInformation model for management and preservation of scientific digital memory of the institute of nuclear engineering, brazil
No full textNew filter for iodine applied in nuclear medicine services
No full textIn NuclearMedicine,radioiodine,invariouschemicalforms,isakeytracerusedindiagnosticpractices
and/or therapy.Medicalprofessionalsmayincorporateradioactiveiodineduringthepreparationofthe
dose tobeadministeredtothepatient.Inradioactiveiodinetherapydosesrangingfrom3.7to7.4GBq
per patientareemployed.Thus,aimingatreducingtheriskofoccupationalcontamination,wedeveloped
a lowcost filter tobeinstalledattheexitoftheexhaustsystem(wheredosesofradioiodinearehandled
within fumehoods,andnew filters willbeinstalledattheirexit),usingdomestictechnology.
The effectivenessofradioactiveiodineretentionbysilverimpregnatedsilica[10%]crystalsandnatural
activatedcarbonwasverified usingradiotracertechniques.Theresultsshowedthatnaturalactivated
carbon andsilverimpregnatedsilicaareeffectiveforI2 capturewithlargeorsmallamountsofsubstrate
but theuseofactivatedcarbonisrestrictedduetoitslow flash point(423K).Besides,whenpoisonedby
organic solvents,this flash pointmaybecomelower,causingexplosionsifabsorbinglargeamountsof
nitrates.ToholdtheCH3I gas,itwasnecessarytousenaturalactivatedcarbonsinceitwasnotabsorbed
by SiO2+Ag crystals.Weconcludedthat,foranexhaust flowrangeof(14572) m3/h, adoublestage filter
using SiO2+Ag inthe first stageandnaturalactivatedcarboninthesecondstageissufficient tomeet
radiological safetyrequirements.In NuclearMedicine,radioiodine,invariouschemicalforms,isakeytracerusedindiagnosticpractices
and/or therapy.Medicalprofessionalsmayincorporateradioactiveiodineduringthepreparationofthe
dose tobeadministeredtothepatient.Inradioactiveiodinetherapydosesrangingfrom3.7to7.4GBq
per patientareemployed.Thus,aimingatreducingtheriskofoccupationalcontamination,wedeveloped
a lowcost filter tobeinstalledattheexitoftheexhaustsystem(wheredosesofradioiodinearehandled
within fumehoods,andnew filters willbeinstalledattheirexit),usingdomestictechnology.
The effectivenessofradioactiveiodineretentionbysilverimpregnatedsilica[10%]crystalsandnatural
activatedcarbonwasverified usingradiotracertechniques.Theresultsshowedthatnaturalactivated
carbon andsilverimpregnatedsilicaareeffectiveforI2 capturewithlargeorsmallamountsofsubstrate
but theuseofactivatedcarbonisrestrictedduetoitslow flash point(423K).Besides,whenpoisonedby
organic solvents,this flash pointmaybecomelower,causingexplosionsifabsorbinglargeamountsof
nitrates.ToholdtheCH3I gas,itwasnecessarytousenaturalactivatedcarbonsinceitwasnotabsorbed
by SiO2+Ag crystals.Weconcludedthat,foranexhaust flowrangeof(14572) m3/h, adoublestage filter
using SiO2+Ag inthe first stageandnaturalactivatedcarboninthesecondstageissufficient tomeet
radiological safetyrequirements
Reactor Kinetic Formulation Using The Finite Element Method
Get PDFThis research has the objective of solving the spatial Kinetic equations for two energy groups using the finite element method. In the methodology, was applied the direct method, such that matrix equations coefficients from spatial discretization was generated by finite element method. The formulation of the time-dependent problem was obtained by analytical integration of precursor concentration equation and using the Euler implicit scheme in the dynamic diffusion problem. A 2D example of a reactor static diffusion problem was solved using a linear triangular finite element. This solution was compared with the numerical benchmark solution, found in the literature, and the numerical results calculated by the finite difference methods. This comparison shows the capacity of the finite element method to obtain a precise solution
