Isotopically Enriched Lithium Fluoride Crystals for Detection of Neutrons with the Fluorescent Track Technique.

In this work, the properties of LiF crystals grown using Li of different isotopic compositions are described from the standpoint of their application as fluorescent nuclear track detectors used in measurements in the neutron radiation fields. The crystals were grown using two techniques: the Czochralski method and the micro-pulling-down method. Three isotopic compositions of Li were studied: natural, highly enriched in Li, and highly enriched in Li.

Application of LiMgPO4 crystal for proton beam quality control in radiotherapy.

The radioluminescence (RL) emitted by LiMgPO4 detector under proton beam irradiation was investigated in real time at the radiotherapy facility in the Institute of Nuclear Physics Polish Academy of Sciences in Krakow. The facility uses protons accelerated by the AIC-144 isochronous cyclotron up to the energy of 60 MeV. The measurements of RL were carried out using a remote optical fiber device with a luminophore detector and photomultiplier located at opposite ends of the optical fiber.

Influence of Elevated Temperature on Color Centers in LiF Crystals and Their Photoluminescence.

The radiation-induced photoluminescence (PL) of LiF has found its way into many applications for the detection and imaging of ionizing radiation. In this work, the influence of thermal treatment at temperatures up to 400 °C on absorption and PL emission spectra as well as fluorescent nuclear tracks in irradiated LiF crystals was investigated. It was found that carrying out PL measurements with the crystals kept at the temperature of about 80 °C leads to a considerable increase in luminescence emission of F color centers at 525 nm.

Uniformity of Thermoluminescence and Optically Stimulated Luminescence Signals Over the Length of Doped LiMgPO Crystal Rods Grown by Micro-Pulling-Down Method.

The purpose of this work was to systematically assess the distribution of thermoluminescence (TL) and optically stimulated luminescence (OSL) properties along the length of crystals grown by the micro-pulling-down method, in relation to the microstructure and distribution of activators. We analyzed lithium magnesium phosphate (LiMgPO; LMP) crystals doped with terbium (Tb; 0.8 mol%) or with a combination of thulium (Tm; 0.

Intrinsic and Dopant-Related Luminescence of Undoped and Tb Plus Tm Double-Doped Lithium Magnesium Phosphate (LiMgPO, LMP) Crystals.

In this work, the luminescence properties of undoped, Tm doped, and Tb plus Tm double-doped crystals of the lithium magnesium phosphate (LiMgPO, LMP) compound were investigated. The crystals under study were grown from melt using the micro-pulling-down method. The intrinsic and dopant-related luminescence of these crystals were studied using cathodo-, radio-, photo-, and thermoluminescence methods.

Thermoluminescence Enhancement of LiMgPO Crystal Host by Tb and Tm Trivalent Rare-Earth Ions Co-doping.

We investigated the influence of terbium and thulium trivalent rare-earth (RE) ions co-doping on the luminescent properties enhancement of LiMgPO (LMP) crystal host. The studied crystals were grown from the melt by micro-pulling-down (MPD) technique. Luminescent properties of the obtained crystals were investigated by thermoluminescence (TL) method.

Optical and thermal pre-readout treatments to reduce the influence of fading on LiMgPO OSL measurements.

TL (Thermoluminescent) and OSL (Optically Stimulated Luminescence) techniques are both luminescent techniques widely applied in several areas into radiation dosimetry. The main difference between them are related to the employed stimulus (thermal or optical) for luminescent emission, as well as the advantages of each technique. Due to simplicity and not to be required heating, the OSL technique has been continuously improved and new researches in materials to be used with this technique have grown in the last decades.

OSL dosimetric properties and efficiency of Brazilian natural calcium fluoride pellets.

Calcium fluoride (CaF), in both natural and synthetic forms, has been exhaustively studied and explored as thermoluminescent (TL) detector. However its sensitivity to ambient light points to the applicability of CaF as OSL (Optically Stimulated Luminescence) detector, increasing the research about its luminescent properties. Although some properties to employ CaF detectors with OSL technique have been already demonstrated, there is a lack of some essential information as the OSL response to different types and energy of ionizing radiation.

IMAGING OF PROTON BRAGG PEAKS IN LiF.

Lithium fluoride (LiF) is one of the most common thermoluminescent phosphors routinely used in radiation protection services. Another advantageous property of LiF is radiophotoluminescence, whose occurs after its irradiation due to the creation of color centers. Excitation of LiF samples with a blue light causes the emission of photoluminescence, which spectrum consists of two peaks at ~520 and ~670 nm.

LITHIUM FLUORIDE CRYSTALS AS FLUORESCENT NUCLEAR TRACK DETECTORS.

Radiophotoluminescence signal of LiF crystals was found to be sufficiently strong to visualize tracks of a single charged particle. This was achieved with a wide-field fluorescent microscope equipped with a ×100 objective and LiF single crystals grown with the Czochralski method at IFJ PAN. The tracks of alpha particles, protons, as well as products of 6Li(n,α)3H reaction with thermal neutrons (moderated Pu/Be source), were observed.

Captopril apparently increase and cisplatin apparently decrease human albumin concentration in artificial urinary solutions.

Background: Measurement of urinary albumin (HSA) is very important in diagnostic of kidney diseases. Much less is known about the possible impact of substances present in urine together with albumin on the results of measurements.

Methods: We investigated the effect of the presence of captopril and cisplatin in the solution on the result of the determination of HSA by native polyacrylamide gel electrophoresis.

Information-theoretic indices usage for the prediction and calculation of octanol-water partition coefficient.

The paper describes the new prediction method of octanol-water partition coefficient, which is based on molecular graph theory. The results obtained using the new method are well correlated with experimental values. These results were compared with the ones obtained by use of ten other structure correlated methods.

Dose perturbation caused by stents: experiments with a model 90Sr/90Y source.

Purpose: Biological effects of intravascular brachytherapy are very sensitive to discrepancies between the prescription and the applied dose. If brachytherapy is aimed at in-stent restenosis, shielding and shadowing effects of metallic stents may change the dose distribution relative to that produced by the bare source. The development of new generations of stents inspired us to a new experimental study in this field.

Ketoprofen ion-selective electrode and its application to pharmaceutical analysis.

The composition of a polymeric potential-determining phase for ketoprofen selective electrode has been determined and the following basic electrode parameters were examined: measurement range, slope characteristic, limit of detection, response time, lifetime and selectivity coefficients in relation to some organic and inorganic anions. The electrode have been used for ketoprofen determination in the range 25.43-25430 microg/mL.

New 2-D dosimetric technique for radiotherapy based on planar thermoluminescent detectors.

At the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ) in Kraków, a two-dimensional (2-D) thermoluminescence (TL) dosimetry system was developed within the MAESTRO (Methods and Advanced Equipment for Simulation and Treatment in Radio-Oncology) 6 Framework Programme and tested by evaluating 2-D dose distributions around radioactive sources. A thermoluminescent detector (TLD) foil was developed, of thickness 0.3 mm and diameter 60 mm, containing a mixture of highly sensitive LiF:Mg,Cu,P powder and Ethylene TetraFluoroEthylene (ETFE) polymer.

On the dose response of some CVD diamond thermoluminescent detectors.

The linearity of dose response of chemical vapour deposition (CVD) diamonds grown at the Institute for Materials Research at Limburg University, Belgium, was investigated over a dose range relevant for radiotherapy. The following CVD diamonds were investigated: (1) a batch of square 3 x 3 mm2 detectors cut from a CVD wafer and (2) an as-grown CVD wafer of 6 cm diameter. A total of 20 CVD square detectors were irradiated with 137Cs gamma rays over the dose range from 200 mGy to 25 Gy.

Two-dimensional thermoluminescence dosimetry using planar detectors and a TL reader with CCD camera readout.

A novel method of determining two-dimensional (2-D) dose distributions is presented, using in-house developed, large-area (a few cm(2)) thermoluminescent (TL) detectors based on LiF powder plated on Al foil. An in-house developed planar large-area TL reader equipped with a coupled charge device (CCD) camera is used for readout, providing digital images of 2-D dose distributions on the surface of these large-area TL detectors. The capability of the newly developed system is demonstrated by mapping 2-D dose distributions around a brachytherapy source, at dose ranges and source geometries relevant for clinical radiotherapy.

Dose distribution around a needle-like anode X-ray tube: dye-film vs. planar thermoluminescent detectors.

The dosimetry around the X-ray tube with a needle-like anode (NAXT), developed at the Institute of Nuclear Studies, for interstitial brachytherapy has been performed using (1) dye films (Gafchromic XR-T), (2) large-area thermoluminescent (TL) detectors--prepared either by gluing TL powder onto thin Al foil (so-called planar detectors with spatial resolution of 0.1 mm) and (3) miniature (2 mm diameter and 0.5 mm thick) TL detectors.

Response of TL dosemeters to cosmic radiation on board passenger aircraft.

Measurements were performed with various LiF based TLDs on board seven Polish aircraft, flying long-distance or middle-distance routes. All of the 7LiF detectors used (various types of 7LiF:Mg,Ti and 7LiF:Mg,Cu,P detectors), which measure the non-neutron component of the radiation field, produced consistent results. It was found that the characteristics of the TLD response (ratio of different detector responses, glow curve shapes) after doses of radiation at flying altitudes differ from those obtained after exposure at the CERN facility (CERF), suggesting a lower contribution of densely ionising radiation.

CVD diamonds as thermoluminescent detectors for medical applications.

Diamond is believed to be a promising material for medical dosimetry due to its tissue equivalence, mechanical and radiation hardness, and lack of solubility in water or in disinfecting agents. A number of diamond samples, obtained under different growth conditions at Limburg University, using the chemical vapour deposition (CVD) technique, was tested as thermoluminescence dosemeters. Their TL glow curve, TL response after doses of gamma rays, fading, and so on were studied at dose levels and for radiation modalities typical for radiotherapy.

Naproxen ion-selective electrode and its application to pharmaceutical analysis.

An ion-selective membrane electrode was prepared based on ion-pair complex of naproxen with methyltrioctylammonium. Its basic analytical parameters such as: slope characteristics, measuring range, detection limit, response time, life time were determined. The electrode showed Nernstian response from the 10(-1) to 10(-4) mol l(-1) concentration range and 5.