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This paper presents the evaluation of an alternative solution for detectors of dual energy x-ray absorptiometry systems. Bone mineral density (BMD) evaluation tools are crucial to the proper diagnosis of osteoporosis. The commercially available DEXA systems utilize CZT as the detector of the small dose of ionizing radiation passing through the area of interest. Our paper presents a novel Strontium Iodide doped with Europium (SrI2:Eu2+) scintillator crystal coupled to a Silicon Photomultiplier (SiPM) array as a less expensive alternative to CZT detector. Dual energy (60 keV and 122 keV) exposure was used for BMD measurements of a bone phantoms containing CaHPO4 to mimic bone and resin to mimic soft tissue. Calibration curves was determined for both BMD and for thickness measurements, validated by “unknown” phantoms. Both calibration curves lead to decreased errors compared to commercially available systems.

Gamma-ray detection and spectroscopy is the quantitative determination of their energy spectra, and is of critical value and critically important in diverse technological and scientific fields. Here we report an improved melt growth method for cesium lead bromide and a special detector design with asymmetrical metal electrode configuration that leads to a high performance at room temperature. As-grown centimeter-sized crystals possess extremely low impurity levels (below 10 p.p.m. for total 69 elements) and detectors achieve 3.9% energy resolution for 122 keV 57Co gamma-ray and 3.8% for 662 keV 137Cs gamma-ray. Cesium lead bromide is unique among all gamma-ray detection materials in that its hole transport properties are responsible for the high performance. The superior mobility-lifetime product for holes (1.34 × 10−3 cm2 V−1) derives mainly from the record long hole carrier lifetime (over 25 μs). The easily scalable crystal growth and high-energy resolution, highlight cesium lead bromide as an exceptional next generation material for room temperature radiation detection., Detection and spectroscopic measurements of gamma-ray used to rely on expensive materials such as CdZnTe crystals. Here He et al. develop a melt method to grow large size CsPbBr3 perovskite crystals and the devices achieve low cost, high energy resolving capabilities and stability.

This paper describes the synthesis, crystal growth, detector fabrication, radiation hardening studies, MCNP modeling, and characterization of lithium indium diselenide or LiInSe 2 . This newly-developed room-temperature thermal neutron detector has semiconducting and scintillating properties and it is suitable for neutron detection application. LiInSe 2 was synthesized starting from elemental Li, In, Se in two steps due to high reactivity of Li. A single crystal of LiInSe 2 was grown using the Vertical Bridgman method . The room temperature band gap was found to be 2.8 eV using optical absorption measurements. Bulk resistivity was measured at ∼ 5 × 1011 Ω cm. Photoconductivity measurements of LiInSe 2 wafers identified a peak in the photocurrent around 445 nm. Nuclear radiation detectors were fabricated from single crystal wafer and the responses to alpha particles at various biases were measured. The mobility-lifetime product was estimated. Gamma irradiation studies were performed with calculated absorbed doses ranging from 0.2126 to 21,262 Gy. The characterization of the two wafers for their scintillator performance was conducted after each irradiation. The gamma irradiation produced a reduction of the light yield that translated to a lower channel number for the centroid of alpha detection spectra. It also showed a considerable reduction of the decay time after the first irradiation. These are the first studies on gamma radiation hardening with this material.

The paper argues that the European Higher Education Area (EHEA) is currently experiencing a crisis of academic freedom and discusses the need to chart a course out of this crisis. The paper claims that the crisis, with its two dimensions (intellectual and empiric), is specific to Europe/EHEA; it is not a global or national crisis, although there are challenges to academic freedom in all other parts of the world and also within individual national higher education systems in Europe. Efforts have been started recently to address key challenges to academic freedom in the EHEA and eventually plot a course out of this crisis. The paper outlines how a comparative and applied interdisciplinary study of these efforts helps reveal their nature and scope, identify the actors/stakeholders involved as well as those, astoundingly, absent; it also allows to discuss and assess early on the chances of success and identify challenges and gaps in these efforts. The paper concludes that charting a course for academic freedom at present in the EHEA is an intergovernmental process. Higher education institutions and academics are not part of this process.

The future of the Bologna Process and the European Higher Education Area (EHEA) have been debated for more than 20 years (Bergan and Deca 2018). From the very start, even as the implementation of this continental-wide project in higher education got underway and in parallel to historical analyses (“looking back” too) that begun slowly to emerge, the future of the EHEA has been a constant preoccupation. It is perhaps in the nature of things that while the future can be close or distant, it never quite arrives, like a textitfata morgana, so that any discussion of “the future” can in principle be endless. Or, it could be that in this case discussions about the future indicate continuing uncertainty about the substance, shape and timeline of a European area for higher education. As we are completing the second decade of the Bologna Process and, if we take a formal approach, the first decade of the EHEA, this debate nevertheless takes on added urgency and includes some new elements. We are encouraged by the fact that few if any voices have been heard advocating an end to the EHEA. We therefore disregard this option here.

This paper reports on successful growth and performance evaluation of two large diameter Cs2HfCl6 (CHC) and Cs2HfCl4Br2 (CHCB), both recently developed scintillator crystals. The discovery of Cs2HfCl6 (CHC) as a scintillator has lately generated much interest in this material and its family, which belongs to the K2PtCl6 cubic crystal structure. CHC is an intrinsic scintillator that is non-hygroscopic (slightly deliquescent, i.e., slightly moisture sensitive but does not deteriorate much when left in air), has no self-radioactivity, provides excellent energy resolution, and has excellent non-proportionality. CHC has a moderate density of 3.9 g/cm3 and an effective atomic number of 58. Reported in this paper are transparent crack-free single crystal CHC and CHCB boules of one inch in diameter, both grown using the vertical Bridgman method. Samples retrieved from the boules, sized ∅23 mm × 30 mm and ∅23 mm × 26 mm, respectively, are characterized for their optical and scintillation properties. Energy resolutions of 3.5% and 3.7% (FWHM) at 662 keV, respectively, are reported. Light yields of 23,000 ph/MeV and 20,000 ph/MeV have been calculated for the large diameter CHC and CHCB crystals, respectively. Results comparable to previously reported results for smaller crystals have been obtained. Studies on decay time, non-proportionality, as well as detector characterization are also reported.

Osteoporosis is a bone disease characterized by low Bone Mineral Density (BMD) leading to a reduction in bone quality.

Lithium indium diselenide, 6 LiInSe 2 or LISe, is a newly developed neutron detection material that shows both semiconducting and scintillating properties. This paper reports on the performance of scintillating LISe crystals for its potential use as a converter screen for cold neutron imaging. The spatial resolution of LISe, determined using a 10% threshold of the Modulation Transfer Function (MTF), was found to not scale linearly with thickness. Crystals having a thickness of 450 µm or larger resulted in an average spatial resolution of 67 µm, and the thinner crystals exhibited an increase in spatial resolution down to the Nyquist frequency of the CCD. The highest measured spatial resolution of 198 µm thick LISe (27 µm) outperforms a commercial 50 µm thick ZnS(Cu): 6 LiF scintillation screen by more than a factor of three. For the LISe dimensions considered in this study, it was found that the light yield of LISe did not scale with its thickness. However, absorption measurements indicate that the 6 Li concentration is uniform and the neutron absorption efficiency of LISe as a function of thickness follows general nuclear theory. This suggests that the differences in apparent brightness observed for the LISe samples investigated may be due to a combination of secondary charged particle escape, scintillation light transport in the bulk and across the LISe-air interface, and variations in the activation of the scintillation mechanism. Finally, it was found that the presence of 115 In and its long-lived 116 In activation product did not result in ghosting (memory of past neutron exposure), demonstrating potential of LISe for imaging transient systems.

This chapter provides an analysis of the evolution of institutional autonomy and academic freedom in Europe since the launch of the Bologna Process and the European Higher Education Area (EHEA). It points to evidence suggesting diverging paths within and between these two areas of university governance. The emergence of a European notion and model of institutional autonomy is one of the most remarkable developments of the period. Although young, this model is already consequential in Europe and it has acquired prominence beyond its borders as well. University autonomy has attracted a lot of attention in the higher education scholarship, policy thinking and regulatory reforms on the continent. Academic freedom, on the other hand, is a largely disregarded and underdeveloped area. At present, the very understanding of the concept of academic freedom and, to some extent, university autonomy is a confused one. A case can be made that they both require attention and that we may need to rethink them afresh in Europe. What is the stake is not primarily a theoretical or conceptual matter, but a practical and moral one.

This chapter discusses why governance and funding are currently serious matters of concern for public policy in the European Higher Education Area (EHEA). It argues that discussions about governance are particularly intense in times of major change in the world around higher education, and that we are once again traversing such a period in Europe. External ruptures in society at-large and changing trends in higher education, which influence the policy discussions and reform initiatives on governance are summarized. The chapter puts forward a synopsis of some of the most important developments in governance and funding since the start of the Bologna Process and launch of the EHEA, and points to important current challenges. Finally, it introduces the papers of the governance and funding section of this volume.

We present a preliminary design for a novel neutron detection system that is compact, lightweight, and low power consuming, utilizing the CubeSat platform making it suitable for space-based applications. This is made possible using the scintillating crystal lithium indium diselenide ( 6 LiInSe 2 ), the first crystal to include 6Li in the crystalline structure, and a silicon avalanche photodiode (Si-APD). The schematics of this instrument are presented as well as the response of the instrument to initial testing under alpha, gamma and neutron radiation. A principal aim of this work is to demonstrate the feasibility of such a neutron detection system within a CubeSat platform. The entire end-to-end system presented here is 10 cm x 10 cm x 15 cm, weighs 670 grams and requires 5 V direct current at 3 Watts.

Lithium containing semiconductor-grade chalcogenide single crystals were grown using the vertical Bridgman method. The source material was synthesized from elementary precursors in two steps, (i) preparing the metal alloy LiIn or LiGa, and (ii) reaction with chalcogen – Se or Te. In a number of experiments, enriched 6 Li isotope was used for synthesis and growth. The composition and structure of the synthesized materials was verified using powder X-Ray diffraction. The energy band gaps of the crystals were determined using optical absorption measurements. The resistivity of LiInSe 2 and LiGaSe 2 , obtained using current–voltage measurements is on the order of 10 8 –10 11 Ω cm. Photoconductivity measurement of a yellow LiInSe 2 sample showed a peak in the photocurrent around 445 nm. Nuclear radiation detectors were fabricated from single crystal wafers and the responses to alpha particles, neutrons and gammas were measured and presented. It suggests that this material is a promising candidate for neutron detection applications.

Cd0.9Zn0.1Te (CZT) based pixelated radiation detectors have been fabricated and characterized for gamma ray detection. Large area CZT single crystals has been grown using a tellurium solvent method. A 10 ×10 guarded pixelated detector has been fabricated on a ~ 19.5 ×19.5 ×5 mm3 crystal cut out from the grown ingot. The pixel dimensions were 1.3 ×1.3 mm2 and were pitched at 1.8 mm. A guard grid was used to reduce interpixel/inter-electrode leakage. The crystal was characterized in planar configuration using electrical, optical and optoelectronic methods prior to the fabrication of pixelated geometry. Current-voltage (I-V) measurements revealed a leakage current of 27 nA at an operating bias voltage of 1000 V and a resistivity of ~ 3.1 ×1010 Ω-cm. Infrared transmission imaging revealed an average tellurium inclusion/precipitate size less than 8 μm. Pockels measurement has revealed a near-uniform depth-wise distribution of the internal electric field. The mobility-lifetime product in this crystal was calculated to be 6.2 ×10 - 3 cm2/V using alpha ray spectroscopic method. Gamma spectroscopy using a 137Cs source on the pixelated structure showed fully resolved 662 keV gamma peaks for all the pixels, with percentage resolution (FWHM) as high as 1.8%.

Lithium containing A I B III C VI semiconductors are being considered as alternative materials for room temperature neutron detection. Materials such as LiGaSe 2 have been synthesized for non-linear optical applications; however, when the crystal is grown enriched in the 6 Li isotope, it is possible to imagine a radiation detector. A nuclear reaction occurs with 6 Li, which can be detected within the semiconductor crystal. As such, high quality crystals are required, which have few defects which prohibit charge collection. One of the primary challenges in growing a high quality crystal is the reactivity of lithium metal. Vacuum purified lithium metal was therefore reacted with gallium to form LiGa as an intermediate to LiGaSe 2 synthesis. Vertical and horizontal Bridgman growth was then conducted to determine the optimal growth conditions. Vertical Bridgman growth resulted in more pure crystals. Annealing in lithium metal vapor reduced crystal defects and improved optical and electrical properties of the subsequent LiGaSe 2 crystal.

The variation in bulk resistivity during infrared (IR) illumination above 950 nm of state-of-the-art CdZnTe (CZT) crystals grown using the traveling heating method or the modified Bridgman method is documented. The change in steady-state current with and without illumination is also evaluated. The influence of secondary phases (SP) on current–voltage (I–V) characteristics is discussed using IR transmission microscopy to determine the defect concentration within the crystal bulk. SP present within the CZT are connected to the existence of deep, IR-excitable traps within the bandgap.

Detector grade Cd0.9Zn0.1Te single crystals were grown using a tellurium solvent method. Single crystal blocks of volume ~1 cm3 were prepared for detector fabrication and characterization. The grown crystals were characterized using infra-red transmission imaging and Pockel's effect measurements. Two detectors in single-polarity charge sensing configurations viz., small pixel, and virtual Frisch grid were fabricated on two crystals obtained from the same section of the ingot. Current-voltage measurements performed in planar configuration exhibited a very low leakage current of ~5 nA at 1000 V and resistivities of the order of 8.5×1010 Ω·cm. Electron drift mobilities of the order of 840 cm2/V.s and electron mobility-lifetime products of the order of 2.7×10-3 cm2/V were calculated from alpha spectroscopy using detectors in planar configuration. The small pixel and the virtual Frisch grid detector showed similar energy resolution of 3.7% for 662 keV gamma rays however, the virtual Frisch grid configuration revealed a better overall performance with a peak-to-Compton ratio of 2.8. A digital spectrometer and related software has been developed using a digitizer card and used to employ offline correction schemes to compensate for the charge loss effects, resulting in significant improvement of the 662 keV peak resolution (1.8% as compared to 3.7% without correction) obtained in the case of small pixel detector.

In this study we review the state-of-the-art for double salt iodide scintillators, in particular cesium barium iodide (CBI), cesium calcium iodide (CCI) and barium bromine iodide (BBI), as well as report on their scintillation and optical properties. Double salt iodides inherently have high density and atomic number which translates to good stopping power for energetic particles, in particular gamma rays. Light yields of 54,000 ph/MeV for CBI, 51,000 ph/MeV for CCI, and 46,000 ph/MeV for BBI were measured. A FWHM energy resolution for the 662 keV full absorption peak was observed at 5.7% for CBI, 16.3% for CCI and 3.56% for BBI. The principal scintillation decay timing for CBI was 840 ns, 462 ns for BBI, and two distinct time components of 9 ns and 1900 ns were observed for CCI.

We report the scintillation properties of both KPb 2 Cl 5 and K 2 CeCl 5 grown by vertical Bridgman method from synthesized and zone refined material. Both crystals exhibit minimal hygroscopic properties, which is desirable in applications where hermitization is not feasible. The KPb 2 Cl 5 crystal, doped with 2.5 mol% of EuCl 2 , appeared yellow in color and did not scintillate, while the self activated transparent K 2 CeCl 5 did. The energy resolution and decay time at 662 keV were measured to be 6.1% and 78 ns respectively, with a light yield of 31,000 photons/MeV.

This paper reports on the charge carrier properties of several lithium indium diselenide (LISe) semiconductors. It was found that the charge collection efficiency of LISe was improved after high flux thermal neutron irradiation including the presence of a typically unobservable alpha peak from hole-only collection. Charge carrier trap energies of the irradiated sample were measured using photo-induced current transient spectroscopy. Compared to previous studies of this material, no significant differences in trap energies were observed. Through trap-filled limited voltage measurements, neutron irradiation was found to increase the density of trap states within the bulk of the semiconductor, which created a polarization effect under alpha exposure but not neutron exposure. Further, the charge collection efficiency of the irradiated sample was higher (14–15 fC) than that of alpha particles (3–5 fC), indicating that an increase in hole signal contribution resulted from the neutron irradiation. Finally, it was observed that significant charge loss takes place near the point of generation, producing a significant scintillation response and artificially inflating the W-value of all semiconducting LISe crystals.This paper reports on the charge carrier properties of several lithium indium diselenide (LISe) semiconductors. It was found that the charge collection efficiency of LISe was improved after high flux thermal neutron irradiation including the presence of a typically unobservable alpha peak from hole-only collection. Charge carrier trap energies of the irradiated sample were measured using photo-induced current transient spectroscopy. Compared to previous studies of this material, no significant differences in trap energies were observed. Through trap-filled limited voltage measurements, neutron irradiation was found to increase the density of trap states within the bulk of the semiconductor, which created a polarization effect under alpha exposure but not neutron exposure. Further, the charge collection efficiency of the irradiated sample was higher (14–15 fC) than that of alpha particles (3–5 fC), indicating that an increase in hole signal contribution resulted from the neutron irradiation. Finally, it wa...

We present a preliminary design for a novel neutron detection system that is compact, lightweight, and low power consuming, utilizing the CubeSat platform making it suitable for space-based applications. This is made possible using the scintillating crystal lithium indium diselenide ($^6$LiInSe$_2$), the first crystal to include $^6$Li in the crystalline structure, and a silicon avalanche photodiode (Si-APD). The schematics of this instrument are presented as well as the response of the instrument to initial testing under alpha radiation. A principal aim of this work is to demonstrate the feasibility of such a neutron detection system within a CubeSat platform. The entire end-to-end system presented here is 10 cm x 10 cm x 15 cm, weighs 670 grams and requires 5 Volts direct current at 3 Watts., Comment: 14 pages, 6 figures

The detection of thermal neutrons has traditionally been accomplished with 3 He-tubes, but with the recent shortage of 3 He, much research has gone into finding suitable replacements. Both relatively inefficient 10 B- and 6 LiF-coated silicon diodes and HgI 2 have been known for many years, and engineered structures in Si that have been filled with 10 B and 6 LiF have shown promise. These devices are intended to realize an optimal juxtaposition of neutron-sensitive material and semiconductor and thereby simulate a semiconductor containing B or Li. Such material has been realized for the first time in the form of 6 LiInSe 2 in which collectable charge from the 6 Li(n,t) reaction indicates a neutron event. In this paper we report neutron and gamma responses of 6 LiInSe 2 , we show pulse height spectra from pure gamma sources and from a thermal neutron source, and we derive the μτ product from the position of spectral features as a function of bias voltage. In addition, we demonstrate the observation of the beta decay of 116m In in samples exposed to thermal neutrons. This feature of the response serves as an additional confirmation of exposure to neutrons.

The original ambition of the section on Financing and Governance of the 2nd Bologna Researchers’ Conference had been to review key aspects in this area along the Bologna action lines.

The paper puts forward arguments in favour of a new approach to the study of internationalisation of higher education. It claims that a systematic mapping of the funding of internationalisation could shed new light on the phenomenon itself and also on the ways it has been conceptualized and studied to date. Preliminary results from a research project adopting this approach are presented, including a series of initial findings and interpretations it has made possible. They provide a basis for the construction of the proposed conceptual framework for the study of internationalisation, which may also serve the creation of heuristic instruments for further research in this context. The paper focuses primarily on potential scholarly contributions (in terms of new knowledge and conceptual refining), and discusses briefly potential lessons to be considered from a policy perspective.

From an educational policy perspective, student centred learning (SCL) is a rather new concept. It has emerged in recent years in national and institutional policy documents, often as part of rather declarative and formal approaches. Such policies are frequently lacking a clearly articulated definition of the concept and its effective operationalization. SCL is a new concept in Romania as well, and its adoption has not been free of difficulties. It is due to the influence of the Bologna Process that SCL is currently becoming an integral part of the strategic framework of universities. The article analyses the understanding of the SCL concept from the perspective of Romanian universities, as well as the extent to which it has been internalized within their processes and practices. The article looks at SCL from two different perspectives: curriculum development (in terms of using learning outcomes and the ECTS) and teaching (in terms of pedagogy and quality assurance). At the same time, the analysis specifically tracks Romania’s commitments regarding SCL within the Bologna Process, and in the broader national higher education policy context.

National strategies and practices in internationalisation of higher education vary across countries. So does their efficiency and impact. For countries that, like Romania, are considering adopting a national internationalisation strategy and are deliberating what exact model to choose (or develop), valuable lessons can be learned from a well-calibrated cross-country comparison. The present study was invited by the Romanian Executive Agency for Funding of Higher Education, Innovation and Development specifically for this purpose. The study is based on a comparative analysis of four European countries: Estonia, Germany, Poland, and Romania. It focuses on aspects such as: existence or not of a national strategy; content of strategies, where they exist, from principles and priorities to legal provisions and budgets; main internationalisation practices, whether linked to a formal strategy or not; main actors at national level; student mobility data. The comparison provides concrete elements for a possible framework informing the choices of the relevant stakeholders/policy makers in Romania. At the same time, it provides surprising insight that may be of interest for policy makers and higher education actors in other countries, as well as for scholars of internationalisation, for example by outlining policy approaches and “country profiles” with regard to internationalisation.

The change in bulk resistivity of CdZnTe (CZT) crystals was measured during infrared (IR) light between 950 and 1000 nm. The crystals are grown using one of the state-of-the-art methods either the traveling heating method or the modified Bridgman method. The change resistivity was evaluated using the steady-state current with and without light. Additionally, the change in current with both IR sources were correlated to the influence of secondary phases (SP) in each crystal using IR transmission microscopy to determine whether the number and size of the impurities has a drastic effect based on the current-voltage (IV) characteristics. SP at various depths within CZT are connected to the existence of variable depth, IR-excitable traps that lie within the bandgap. The release of these traps will significantly affect the overall current in the system. However, the current increase may not match the overall energy of the light utilized are more dependent on the size and quantity for each energy range.

Chalcopyrite crystals of 6LiInSe2 have recently been shown to respond to gamma and thermal neutron radiation. Thus far, large crystals have been prepared although the charge collection efficiency has not been sufficient for high energy resolution. In an effort to improve energy resolution needed for gamma spectroscopy as well as pulse shape discrimination for mixed gamma neutron fluxes, the precipitate concentration within the 6LiInSe2 crystal have been studied. The precipitate volume greatly affects the energy resolution in the pulse height spectrum. Further, the charge mobility varies greatly with holes being preferentially trapped by these precipitates or some other defect site within the crystal.

Cd 0.9 Zn 0.1 Te (CZT) gamma radiation detectors are presently among the best semiconductor materials for room temperature operation. CZT crystals in pixilated geometry can be efficiently used in the field of Homeland security and medical diagnosis for high resolution imaging purpose and position sensitive measurements using x-rays and high energy gamma rays. Large area CZT single crystals has been grown using a tellurium solvent method. A 10×10 guarded pixilated detector has been fabricated on a ∼19.5×19.5×5 mm3 crystal cut out from the grown ingot. A full area planar Au contact was used as the cathode. Each pixel of the pixilated detector was 1.3×1.3 mm2 in area and pitched at 1.8 mm. A 100 μm wide guard grid was used to reduce inter-pixel leakage. The crystal was characterized in planar configuration using electrical and optoelectronic methods prior to the fabrication of pixilated geometry. Current-voltage (I–V) measurements revealed a leakage current of 29 nA at an operating bias voltage of 1100 V. A resistivity of ∼3.1×1010 ∖.cm was calculated from the I–V measurements. Infrared transmission imaging revealed an average tellurium inclusion/precipitate size less than 8μm. Pockels measurement has revealed a near-uniform depth-wise distribution of the internal electric field. The mobility-lifetime product in this crystal was calculated to be 6.2 × 10−3 cm2/V using alpha ray spectroscopic method. Gamma spectroscopy using a 137Cs source on the pixelated structure showed fully resolved 662 keV gamma peaks for all the pixels, with percentage resolution (FWHM) as low as 1.8 %.

The article proposes to characterize the Bologna process as a knowledge society project. Viewed in this perspective, the Bologna process appears to be a surprising success story. Success is expressed in the capacity of the project to generate innovation in higher education, its real impact in Europe, and its global prominence. A major shortcoming of the Bologna process as a project is in the area of funding. The article argues that it is more useful to talk of a funding policy gap in the European Higher Education Area, rather than simply a funding gap. An explanation is proposed for this situation, as well as recommendations regarding a possible way forward.

We are developing new scintillator materials that offer potential for high resolution gamma ray spectroscopy at low cost. Single crystal SrI 2 (Eu) offers ∼3% resolution at 662 keV, in sizes of ∼1 in3. We have developed ceramics processing technology allowing us to achieve cubic inch scale transparent ceramic scintillators offering gamma spectroscopy performance superior to NaI(Tl). Our bismuth-loaded plastic scintillator demonstrates energy resolution of ∼8% at 662 keV, for samples of ∼0.5 cm3.

This paper presents a method for measuring the electric and magnetic field with one sensor. The solution suggested is a simple one, and makes possible the extension, under 100 kHz, of the frequency range of the sensors used for electric and magnetic field measurements in the same place in space.

The paper analyses stereotypes and prejudices of the Romanian majority about three ethnic minorities: Jews, Gypsies and Hungarians. The specific role those stereotypes play, their origin, and several examples of discrimination are explained in relation to demographic, economic, political and cultural factors, including types of prejudices other than ethnic. The nature of the interaction between international public opinion, the Romanian state and civil society is considered to be responsible for the specific forms which prejudice and discrimination take in contemporary Romania.

Single crystals of semiconductor-grade lithium indium selenide (LiInSe2) were grown using the vertical Bridgman method. The orthorhombic structure of the materials was verified using powder x-ray diffraction. The room temperature band gap of the crystal was found to be 2.85 eV using optical absorption measurements. Resistivity of LiInSe2, obtained using current-voltage measurements, has semiconducting nature (decreases with increasing temperature) and is in order of 1010 Ω·cm. Photoconductivity measurement showed the photocurrent peak at 445 nm. Nuclear radiation devices were fabricated, and alpha particle detection was observed, suggesting that this material could be a candidate for neutron detection applications.