Abstract:
A scintillation compound, other than a rare earth silicate, can include a rare earth element that is in a divalent (RE2+), trivalent (RE3+) or a tetravalent state (RE4+). The scintillation compound can include another element to allow for better change balance. The other element may be a principal constituent of the scintillation compound or may be a dopant or a co-dopant. In an embodiment, a metal element in a trivalent state (M3+) may be replaced by RE4+ and a metal element in a divalent state (M2+). In another embodiment, M3+ may be replaced by RE2+ and M4+. In a further embodiment, M2+ may be replaced by a RE3+ and a metal element in a monovalent state (M1+). The metal element used for electronic charge balance may have a single valance state, rather than a plurality of valence states, to help reduce the likelihood that the valance state would change during formation of the scintillation compound.
Abstract:
A scintillation compound, other than a rare earth silicate, can include a rare earth element that is in a divalent (RE 2+ ), trivalent (RE 3+ ) or a tetravalent state (RE 4+ ). The scintillation compound can include another element to allow for better change balance. The other element may be a principal constituent of the scintillation compound or may be a dopant or a co-dopant. In an embodiment, a metal element in a trivalent state (M 3+ ) may be replaced by RE 4+ and a metal element in a divalent state (M 2+ ). In another embodiment, M 3+ may be replaced by RE 2+ and M 4+ . In a further embodiment, M 2+ may be replaced by a RE 3+ and a metal element in a monovalent state (M 1+ ). The metal element used for electronic charge balance may have a single valance state, rather than a plurality of valence states, to help reduce the likelihood that the valance state would change during formation of the scintillation compound.
Abstract:
The present disclosure describes a scintillation crystal having the general formula RE(1-y)MyF3XA3(1-x), wherein RE is selected from the group consisting of La, Gd, Y, Lu, or mixtures thereof; A is selected from Cl, Br or I, and M is an activator ion selected from the group consisting of Ce3+, Pr3+ or Eu3+ and combinations thereof containing two or all three activator ions and further optionally comprising Ho, Er, Tm, or Yb also in the 3+ oxidation state. We also disclose a scintillation detector including a scintillation crystal, and downhole tools and methods of oil exploration utilizing such scintillation crystals.
Abstract:
A method of preparing a lanthanide-doped nanoparticle sol-gel matrix film having a high signal to noise ratio is provided. The sol-gels are also provided. A method of preparing light emitting sol-gel films made with lanthanide doped nanoparticles, for the production of white light is also provided. The method comprises selecting lanthanides for the production of at least one of green, red and blue light when excited with near infrared light, preparing nanoparticles comprising the selected lanthanides, stabilizing the nanoparticles with ligands operative to stabilize the nanoparticles in an aqueous solution and selected to be substantially removed from the sol-gel matrix film during synthesis, incorporating the stabilized nanoparticles into a sol-gel matrix and heating to increase the signal to noise ratio of the luminescence by substantially removing the low molecular weight organic molecules. Additionally, light emitting sol-gel films made with lanthanide doped nanoparticles are provided.
Abstract:
The present invention relates to an advanced product security system comprising at least one up-converting material as a security marking and at least one authenticating equipment, in particular a reader. The authenticating equipment comprises at least one first source of electromagnetic radiation of at least one first preselected wavelength and at least one second source of at least one second preselected wavelength which are different from each other. The radiation of the first and of the second wavelength are selected such as to cause the up-converting material upon combined radiation with said first and second wavelength to release an emission spectrum. The electromagnetic emission spectrum of said up-converting material comprises radiation of at least one wavelength which is specific for the return of at least one electron from an energy level to which the electron is raised by the combined radiation of at least said first and said second wavelength.
Abstract:
Spherical particles of fluoride up-converter phosphors having a particle size of 1 micron and less can be made from their corresponding precursor hydroxycarbonate particles by heating the hydroxycarbonate particles in an oxygen-containing atmosphere to convert the hydroxycarbonate to the corresponding oxide but without changing the size and shape of the particles, and then heating the phosphor oxide particles to their corresponding fluoride particles by heating in SF6, at a temperature that will crack the SF6 but will not change the size or shape of the phosphor particles.
Abstract:
본 발명은 섬광체(scintillator), 이의 제조 방법 및 응용에 관한 것으로, 본 실시 예에 따른 섬광체는 탈륨, 란타늄 및 할로겐 원소를 주성분으로 포함하는 모체; 및 모체에 도핑된 활성제를 포함한다. 본 발명의 실시 예에 따른 섬광체는 화학식이 Tl a La b X c :yCe 로 주어지며, X는 할로겐 원소이고, a=1, b=2, c=7 이거나, a=2, b=1, c=5 이거나, 또는 a=3, b=1, c=6 이고, y 는 0 보다 크고 0.5 이하이다. 본 발명의 실시 예에 따른 섬광체는 방사선에 대한 검출 효율이 높고, 광출력이 크며, 형광감쇠시간 특성이 우수하다.
Abstract:
A scintillation crystal can include Ln(1-y)REyX3, wherein Ln represents a rare earth element, RE represents a different rare earth element, y has a value in a range of 0 to 1, and X represents a halogen. In an embodiment, RE is Ce, and the scintillation crystal is doped with Sr, Ba, or a mixture thereof at a concentration of at least approximately 0.0002 wt.%. In another embodiment, the scintillation crystal can have unexpectedly improved linearity and unexpectedly improved energy resolution properties. In a further embodiment, a radiation detection system can include the scintillation crystal, a photosensor, and an electronics device. Such a radiation detection system can be useful in a variety of radiation imaging applications.