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Cesium-134 artylon sealed source based on inorganic adsorbent (as a core) was easily prepared. The sealed source was in the form of a disk constituted of two halves; base and top. Cesium-134 was adsorbed by equilibration of 134CsCl solution with WO3 inorganic adsorbent at pH 4 for 24 h at 25±1°C. Then, the liquid phase was decanted and checked for the remaining activity. Thereafter, the 134Cs-loaded WO3 was dried at 100 °C for 24 h. A definite weight the 134Cs-loaded WO3 adsorbent was placed in the central cavity of the base half-disk. Then the two half-disks were assembled using a commercial epoxy adhesive. The activity values of the sealed source were 7.81×10-2 and 7.70×10-2 Ci, calculated by using the absolute efficiency curve and DETEFF software were found to be closest at a 5 cm source-detector distance; respectively. After radiometric standardization and encapsulation, the sealed source was checked radiometrically before release to the local market for calibration purposes of radiation measurement and identification instruments.

It is predicted that crystalline silicon passivated emitter and rear contact (c-Si PERC) solar cells will reach 70% global market share with the cell thickness decreased to 150 μm within next 7 years. It is of critical importance to address efficiency loss in order to deliver high cost-effective thinned Si cells. Herein, we not only address the efficiency loss but also acquire an extra gain for 150 μm-thick cells via optical and electrical designs. By rear design of SiNx/SiOx film, light absorption loss at longer wavelengths is made up. Via front design of SiO2/SiNx/SiOx film, light absorption at short wavelengths is enhanced and simultaneously, open circuit voltage (Voc) is considerably improved. Compared with standard 180 μm-thick cells, the present design experimentally lead to average short circuit current density (Jsc) increase by 0.2 mA/cm2 and average Voc improvement by 9 mV. Compared with standard thick cells and un-designed 150 μm-thick cells, net absolute efficiency gains are up to 0.4% from 22.0% to 22.4% and 0.6% from 21.8% to 22.4%, respectively. Device simulations are conducted to explain the experimentally observed improvements. The present study demonstrates a technical solution to address the efficiency loss in the thinned c-Si PERC cells.

The article describes the effectiveness of the application of a comprehensive methodology in the modernization of the flow parts of steam turbines. The above methodology makes it possible to increase the absolute efficiency by 0.83%, and the turbine power by 1.87% due to the use of an object-oriented approach. The use of recursive traversal of various optimization levels for information exchange between objects allows finding an optimal solution for a large number of design parameters., В статті викладено ефективність застосування комплексної методології при модернізації існуючих проточних частин парових турбін. Наведена методологія дозволяє збільшити абсолютний ККД на 0,83%, а потужність турбіни на 1,87% за рахунок використання об’єктно –орієнтованого підходу. Використання рекурсивного обходу різних рівнів оптимізації задля обміну інформацією між об’єктами дозволяє знайти оптимальне рішення для великої кількості конструктивних параметрів.

We report on an apparatus able to measure the absolute detection efficiency of a detector for electrons in the 30 - 900 eV range. In particular, we discuss the characterisation of a two-stage chevron microchannel plate (MCP). The measurements have been performed in the LASEC laboratory at Roma Tre University, whit a custom-made electron gun. The very good stability of the beam current in the fA range, together with the picoammeter nominal resolution of 0.01 fA, allowed the measurement of the MCP absolute efficiency $\epsilon$. We found an $\epsilon$ = (0.489 $\pm$ 0.003) with no evident energy dependence. We fully characterised the MCP pulse shape distribution, which is quasi-Gaussian with a well visible peak above the noise level. We measured a 68% variation of the average pulse height between 30 and 500 eV. Furthermore, with a deeper analysis of the pulse shape, and in particular of the correlation between pulse height, area and width, we found a method to discriminate single- and multi- electron events occurring within a 10 ns time window., Comment: 15 pages, 25 figures

The purpose of the study was a hygienic assessment and generalization of practical experience of the St. Petersburg Rospotrebnadzor Office and the Center for Hygiene and Epidemiology in St. Petersburg acquired within the framework of the established powers in supervision and control of radiation safety of the population and combating radiation terrorism when preparing and holding mass events of 2018 FIFA World Cup in St. Petersburg. Materials and methods. We used the materials on planning and implementing measures to ensure radiation safety of the population and reports of the St. Petersburg Rospotrebnadzor Office and the Center for Hygiene and Epidemiology in St. Petersburg for 2016–2018. Results. We made a hygienic assessment of comprehensive measures for supervision and control over ensuring radiation safety of the population in preparation for mass sporting events, summarized the practice and efficient results of organizing and conducting monitoring of the radiation situation, radiation monitoring at infrastructure facilities, including radiological studies during the construction and reconstruction of sports facilities, and radiation control of baggage X-ray inspection systems used at the sites of sporting events for additional security measures. A scheme of organizing radiation monitoring of building materials and products delivered to sports facilities under construction was developed to eliminate excessive costly spectrometric studies while guaranteeing effectiveness of radiation monitoring. We demonstrated that an important step in the integrated approach to ensuring radiation safety was the control over introduction of additional safety measures immediately at the facilities operating on radioactive substances and posing radiation hazard in St. Petersburg, taking into account the category of their potential radiation hazard, as well as the preparedness of specialized Rospotrebnadzor units to promptly respond to emergency situations. Activities of the Regional Interdepartmental Operational Headquarters for Security showed absolute efficiency of interdepartmental cooperation between federal and municipal executive authorities.

PurposeThere has been a persistent debate on measures of efficiency and ranking procedures of higher education institutions (HEIs). Deriving absolute efficiency measures and their ranking provide a critical input for the society to choose the appropriate educational institute. The purpose of this paper is to evaluate the relative performance of institutions in management education in different locations in India and propose a holistic efficiency measurement which can be applied to HEIs in general.Design/methodology/approachThis study uses dynamic data envelopment analysis (DDEA) as the primary methodology of analysis. Multiple measures of inputs and output have been defined to assess efficiency in institutions of management education. Some of the output variables used for measuring relative effectiveness are: the number of students placed, number of entrepreneurs, median CTC of placed students, total number of students passed, number of research publications, number of students and faculty who have participated in international exchange, input variables used, student intake, faculty profile, resource allocation on the development of student, faculty and staff, industry linkages, alumni network. The institutions under study are in three different locations in India, having distinct characteristics. The multiple measures of inputs and outputs defined have been used to measure efficiency, following which DDEA was used to rank the efficiency measures.FindingsVarious agencies use their framework to evaluate and rank HEIs; however, they are either subjective or less researched methodologies. The proposed method acts as a new researched and objective methodology for ranking of HEIs operating across regions with different societal, economic and political contexts. Efficiency in education is of high relevance today for various stakeholders such as students, parents, industry, policy-makers and government. An objective, such as the one proposed in this paper, would be helpful in satisfying the needs of various stakeholders. Furthermore, the government has policies of allocating funds, in case of public-funded institutions, based on efficiency levels in HEIs. The measure using DDEA suggested in this study provides a better measurement of efficiency.Research limitations/implicationsThis research is based on the extension of DDEA with slight modification to the denominator portion of efficiency calculation. The modification is accentuated by taking an industry benchmark or government benchmark. This may lead to slight difficulty in the appropriation of input parameters. Hence, selection of appropriate input and output parameters is the key limitation. To demonstrate capabilities of the proposed approach, this framework is implemented for performance evaluation of institutions of higher education in India. Some helpful policy-making and managerial insights are derived from the numerical results.Originality/valueThe uniqueness of this research is that it adds a well-researched methodology based on DDEA to measure efficiency and rank HEIs for effective assessment and benchmarking. The frameworks used so far have been either subjective or less researched methodologies.

Adsorption of natural gas (methane) on the synthesized metal–organic framework (MOF) Al-BTC with specific surface area SBET = 1422 m2/g was studied at pressures up to 40 MPa and temperatures of 303, 313, 323, and 333 K. The maximum adsorption of methane on Al-BTC reaches 10.36 mmol/g at 303 K and 40 MPa, and the initial heat of adsorption is ~14 kJ/mol. The amount of methane accumulated in a system with Al-BTC attains a value of 120–130 m3(NTP)/m3 in a range of pressures from 3.5 to 10.0 MPa, which is the most relevant for methane accumulation. The volumes of methane stored in the systems with Al-BTC and without an adsorbent differ by a factor of about 2 at 3.5 MPa, there is almost no distinction between these options of methane storage at 7.0 and 20.0 MPa, and the amount of gas in the system without an adsorbent exceeds by 25% that in Al-BTC. The pressure range from 3.5 to 6.0 MPa is most efficient for the methane adsorption accumulation in the MOF structure Al-BTC. The absolute efficiency of methane adsorption accumulation increases with lowering of temperature.

A Geant4 simulation has been carried out in order to determine the B-detection efficiency of a rare isotope beam implantation setup, for decay spectroscopy experiments, comprising a number of Double Sided Silicon Strip Detectors (DSSSDs) and two plastic scintillation detectors placed upstream and downstream. The absolute efficiency for the emitted B-particle detection from radioactive fragments implanted in the DSSSDs using fast-timing plastic-scintillator detector, is calculated. The detection efficiency of the setup has been studied with two different distances between the Si layers and plastics. The requirement for the thickness of the Si detector layers and its implication on the B-detection effciency has been investigated for 1 mm and 300 um thickness of Si layers. The combined efficiency of DSSSD and plastic detectors were also simulated for two different thicknesses of the DSSSD.

Precision planting represents an opportunity for farmers to increase income. Seeders and associated seed meters are prerequisite to achieve optimal plant density. However, to assure seed meter performance in smallholder conditions, a comprehensive procedure is lacking. This study develops a methodology for mechanical maize meter evaluation that compares diverse meters in terms of seed singulation, seed damage, and spatial distribution. An experiment assessed 10 m, representing roller types, and inclined, vertical, and horizontal plates collected from various continents and representative of commonly used devices by smallholders. A conveyer-belt setup allowed for seed distribution analysis and the influence of vibration and topography on the seed singulation was determined. Results revealed that a rotational velocity of 20 revolutions per minute (RPM) was optimum for most meters, while all complied with the norm NMX-O-168-SCFI-2009 in terms of seed damage. Independent of the singulation mechanism, devices with the ability to adjust to seed size performed better. The Fitarelli horizontal plate, followed by the BARI-9 inclined plate meter, are considered ‘best-bet’ performers. Although, considering absolute efficiency, two inclined plate devices worked at near-perfect performance with large seeds. Our study develops a low-cost methodology, easily replicated and implemented, and provides a baseline for continued research on seed meter evaluation.

Dried blood spots (DBS) are widely utilized as part of universal newborn screening and as a means of transporting samples from field sites. We use DBS from African field sites to assess for rare maternal-fetal cell exchange during pregnancy known as microchimerism. We aimed to develop a protocol to maximize the quantity of high-quality genomic DNA (gDNA) extracted from DBS. The total gDNA yield obtained from control DBS utilizing a Qiagen-based protocol and a Chelex® 100 resin-based protocol was first compared. Variations of the Chelex® protocol were subsequently tested to develop an optimized protocol. The gDNA was quantified by qPCR targeting the human beta-globin gene. DNA yield for a given experimental condition was normalized to a Chelex® control performed on the same day, and the total yields were compared using a Student’s t-test. The control Chelex® protocol yielded 590% more DNA than the QIAamp® DNA Blood Mini Kit . The absolute efficiency of the control Chelex® protocol was 54%, compared to an absolute efficiency of 9% for the QIAamp® DNA Blood Mini Kit. Modification of the Chelex® protocol to include a second heat precipitation from the same DBS increased the gDNA yield by 29% (P

During the last decades, many water treatment processes have been proposed to deal with the increasing water quality requirements demanded for the urban wastewater effluents (UWWE). Among them, the so-called Advanced Oxidation Processes (AOPs) include a wide range of technologies based on the generation of very reactive and non-selective radical species with a strong oxidation potential that can readily remove not only PhACs but also other organic micropollutants. Together with ozone-based processes, these technologies constitute promising alternatives to be used as final barrier to remove these contaminants before the discharge of the effluents to the environment. This chapter focuses on the processes with higher potential to be implemented at large scale for the removal of PhACs in urban wastewater treatment plants: ozone-based, Fenton, and UV/H2O2 processes. Along the chapter, the fundamentals of these processes are introduced, including some of the more relevant modifications from the basic processes, and the more recent studies about their application for the removal of PhACs from UWWE at pilot and full scale are reviewed. From a scientific and technical point of view, the results from these researches confirm the successful removal of a wide range of PhACs and other micropollutants, although the absolute efficiency depends on the water matrix and the specific substances monitored along the treatment. As final remarks, other aspects are also included, such as the need to control the potential formation of by-products during the process and the required optimization of the processes to become competitive in economic terms.

Measurement of nuclear materials by ISOCS technique an important and significant tool for IAEA activities verification. ISOCS technique able to measuring samples with different geometry. In this work, ISOCS technique was used to calculate the absolute efficiency of the Hyper Pure Germanium (HPGe) detector. The calculated absolute efficiency of the detector was used in combination with experimental work to determine U-235 mass in cylindrical NM samples. A good agreement was obtained when compared estimated and declared values of 235U mass content with difference in the ranged from −0.827% to 1.635%.

Sevoflurane is one of the widely used inhalation anesthetics as well as desflurane, which started to be used in Russia in 2012. These drugs possess similar properties; however, desflurane provides faster restoration of cognitive functions and reduces the time to extubation. This study was aimed to investigate the impact of properties of these medications on pharmacoeconomic parameters. The objective is to evaluate pharmacoeconomic parameters of anesthesia with desflurane and sevoflurane in a medical unit, investigating their impact on the performance of surgical teams and opportunity to introduce Fast-track surgery in the Russian Federation. Methods. For the purpose of cost-effectiveness analysis (CEA), the time period for simulation of the compared regimens made 1 year. And the time period for budget impact analysis (BIA) and additional analysis of Fast-Track surgery made 3 years. Results of randomized clinical trials were used as a source of data on safety and clinical efficiency. The simulated groups (100 patients each) were formed for the purpose of analysis. The decision tree was used, including all direct medical costs of anesthesia, and surgery in general (dextral hemicolectomy was analyzed). The number of surgeries performed in case of the maximum load in a medical unit was used as an efficiency criterion for CEA, and the full scope of costs for additional surgeries was also included. Result: Desflurane demonstrated maximum absolute efficiency, expressed as the number of surgeries in case of the maximum load in a medical unit, i.e. the best rate of cost-effectiveness (CER). CER for the regimen with desflurane made 63,251 RUR and CER for the one with sevoflurane made 63,841 RUR, The budget impact analysis showed that use of desflurane reduced the budget costs by 153,467 RUR during 3 years (provided that there are 247 surgeries per year and 3 surgeries per day). Sensitivity analysis confirmed the invariance of the obtained results. Analysis of potential introduction of Fast-Track surgeries showed that its use was associated with reduction of budget costs by 8,013,182 RUR. Conclusion: Use of anesthesia with desflurane resulted in higher effectiveness and was the most cost-effective providing reduction of budget costs.

This paper presents the methods to determine the detection efficiency of the segmented germanium detector. Two methods are given for the investigating the detection efficiency of the semiconductor segmented-germanium detector. Experimental measurements using radioactive sources are reported. The radioactive sources, which were involved, can give us the opportunity to cover the photon energy ranging up to hundreds of keV. A useful compilation is included of the latest values of the emission rates per decay for the following radioactive sources: 241Am and 133Ba. The second method, the simulation of the efficiency is involved for comparison purposes. A good agreement between the measurements and the simulation is obtained. Keywords: Absolute efficiency, Radioactive source, Segmented geometry detector

In the present work, the authors aim to determine the efficiency of the macroeconomic policies by determining the effects of the application of the instruments (revenue change) and finding out the instrument having the highest efficiency. In today’s macroeconomic theory and practice, the efficiency level of the macroeconomic policy instrument is measured using multipliers. The different nature of the measurement units used when calculating the multipliers makes it impossible to compare the multipliers in order to establish the more efficient instrument, and for this reason it becomes necessary to use elasticity as an efficiency indicator.

One of the leading goals in novel breeding programs on table grapevine is the set-up of novel seedless varieties. Seedlessness has a strong impact on consumers’ choices representing an important added economic value compared to traditional cultivars. Breeding in tree crops greatly benefits from the use of molecular markers associated to a trait of interest. Nevertheless, one of the main limitations hampering marker assisted breeding is the lack of marker validation on multiple genetic backgrounds. To this extent, we evaluated the efficiency of four markers linked to seedlessness on 97 F1 genotypes derived from 16 cross combinations obtained through in vitro embryo rescue. Our results confirmed that the four markers were associated to seedlessness even though all, to a different extent, showed marker-trait inconsistencies. Marker efficiency was then tested on the different genetic backgrounds composing the entire germplasm providing a more acurate overview of the marker performances when the genetic background changes. Overall, the most efficient markers were VMC7f2 and p3_VvAGL11 even though their effectiveness changed remarkably from one genetic background to another. This work reports a marker validation assay on a germplasm created to encompass the actual allelic variability employed by breeders. The results could represent a valuable tool to guide the choice of the best markers to assist selection, a choice that should be based, more than on the absolute efficiency of the marker, on a careful evaluation of its performance on the genetic backgrounds in analysis.

This study aims to assess for the first time the natural radioactivity and radiation dose induced from smoking. Different brands of tobacco cigarettes, commonly marketed in Albania, were collected in 10 packs of 20 cigarettes each. A broad energy High-Purity Germanium (HPGe) system, with relative efficiency 40%,has been used in order to determine the radionuclides present in cigarette tobacco. The LabSOCS (Laboratory SOurceless Object Calibration Software) was used to simulate the absolute efficiency curve for organic matrix in the energy range from 20 keV to 2000 keV. The average values of the activity concentrations were 13.4 ± 3.7, 5.3 ± 2.3, 839.1 ± 29 Bq/kg for 226Ra (214Bi, 214Pb), 232Th (228Ra, 228Th) and 40K, respectively. The artificial radionuclide of 137Cs was found to be under the detection limit for the measured cigarette tobaccos. These results were compared with available data in the literature. The annual effective dose, the annual gonadal dose equivalent and the excess life cancer risk was calculated to evaluate the radiological hazard for smokers in Albania.

A GaAsP/SiGe tandem solar cell on Si substrate has been further fabricated using light trapping techniques, such as texturing and adding a back surface reflector, and thinning the Si substrate. This is of importance to increase the Jsc of the Si0.18Ge0.82 bottom cell in this tandem system since bottom cell is current limiting. The Jsc of the bottom cell has been increased by relative 7.4%. This current improvement leads to a predicted efficiency of near 21% for this tandem device, with an absolute efficiency improvement of 0.3% over previous results without light trapping processes. The current of the bottom cell can be further improved by optimizing the bottom cell structure and texturing process, further thinning the Si substrate and increasing Ge concentration. (© 2016 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim)

High energy γ-ray can be used in many fields, such as nuclear resonant fluorescence, nuclear medicine imaging. One of the methods to generate high-energy γ-ray is nuclear resonant reaction. The 19F (p,αγ) 16O reaction was used to generate 6.13-MeV γ-ray in this work. The angular distribution of 6.13-MeV γ-ray was measured by six LaBr3 detectors. The thick-target yield curve of 6.13-MeV γ-ray had been measured. The maximum yield was determined to be (1.85 ± 0.01) × 10−8 γ/proton, which was measured by HPGe detector and LaBr3 detector. The absolute efficiency of all the detectors was calibrated using 60 Co and 27Al (p,γ) 28Si reaction at E p = 992 keV. The cross section and total resonant width of the reaction were determined to be 95.1±1.0 mb (1 b = 10−24 cm2) and Γ CM = 2.21±0.22 keV, respectively.

The cast-grown monocrystalline-like silicon (mono-like Si) technology has been reactivated recently for the manufacture of high-efficiency solar cells at low cost. In this paper, we have provided a progressive research, both experimentally and theoretically, to improve the efficiency of mono-like Si passivated emitter and rear cells (PERCs) through production lines. By employing rear surface passivation of AlOx/triple-SiNx:H layers, the average efficiency has increased to 21.87% with a champion efficiency of 22.32% from the standard mono-like Si PERCs of 21.72% efficiency with AlOx capped with double-SiNx:H layers. We have further optimized the rear electrode contact patterns and introduced the selective emitter (SE) technology, yielding an absolute efficiency improvement of 0.19% and 0.26%, respectively. Integrating all approaches of the triple-SiNx:H, rear contact pattern optimization and SE technology, we have demonstrated that the mono-like Si PERCs can reach the average efficiency of 22.2% with a maximum efficiency of 22.5%, similar to the current Czochralski monocrystalline Si counterparts.

The traditional practice of comparing actual productivity versus historical productivity only provides relative efficiency data rather than absolute efficiency data. Innovatively, a two-pro...

Single junction concentrator solar cells operate at efficiencies that are surprisingly close to their one-sun equivalents cells; for the case of GaAs the 1-sun efficiency record stands at 28.8% while under concentration it stands at 29.3%. This arises due to three effects: Firstly the AM1.5G spectrum has a stronger blue component than the AM1.5D low-AOD concentrator spectrum and hence yields higher efficiency from higher band-gap cells. Secondly the 1-sun GaAs device achieves an approximate 2% absolute efficiency increase due to the removal of the substrate; a feature that is absent from the concentrator cell. Thirdly, the difficulty of achieving front metal grid structures that are sufficiently conductive to enable peak efficiencies at several hundred suns frustrates the achievable efficiency of a GaAs solar cell.Single junction concentrator solar cells operate at efficiencies that are surprisingly close to their one-sun equivalents cells; for the case of GaAs the 1-sun efficiency record stands at 28.8% while under concentration it stands at 29.3%. This arises due to three effects: Firstly the AM1.5G spectrum has a stronger blue component than the AM1.5D low-AOD concentrator spectrum and hence yields higher efficiency from higher band-gap cells. Secondly the 1-sun GaAs device achieves an approximate 2% absolute efficiency increase due to the removal of the substrate; a feature that is absent from the concentrator cell. Thirdly, the difficulty of achieving front metal grid structures that are sufficiently conductive to enable peak efficiencies at several hundred suns frustrates the achievable efficiency of a GaAs solar cell.

Construction of detector is necessary. However, on large energy range the manufacturers could not also support the explicit function of relative and absolute efficiencies of detectors. One of the reasons is a restriction of energy range of gamma sources (normally < 3 MeV). This paper presents the results of construction of relative and absolute efficiency functions within a range from 122 keV to 8.5 MeV. The sources are used combining 152Eu point source and 36Cl activated isotope by thermal neutron captured reaction 35Cl of Dalat nuclear reactor (DNR) by 35Cl(n, γ)36Cl reaction. This result can be applied in determining quantitative analysis of samples of neutron activation and radioactivity chemistry

Planar lens is one of the most important components of both microwave and optical frequency regimes. However, current available transmissive lenses are limited by their low efficiency, complex configurations and large sizes. Here, we propose a general strategy to design focusing meta-surface by using carefully designed Huygens elements. Each element on the meta-surface can realize very high transmission due to the electric and magnetic currents deduced by electric and magnetic structures, respectively. As proof of the concept, a meta-lens, working at frequency of 10 GHz is designed, fabricated and measured. Our meta-lens consists of 31 × 25 Huygens elements, occupying a total area of 155 × 164.3 mm2. Numerical and experimental results agree well with each other. The measured absolute efficiency of our meta-lens is higher than 86.7% (90.6% for simulation) at the working frequency. Moreover, the bandwidth is about 30.7% (32.5% for simulation). Our finding opens up a new avenue to design high-performance microwave meta-devices working in transmission geometry.

Optimal productivity is the highest sustainable productivity level achievable under good management and typical working conditions. Accordingly, optimal productivity provides the foundation for determining the absolute efficiency of construction operations because an accurate estimate of optimal productivity enables the comparison between actual versus optimal rather than actual versus historical productivity. This research contributes to the current body of knowledge by introducing a two-prong strategy for estimating optimal productivity in labor-intensive construction operations and by applying this strategy to a pilot study on the replacement of electrical lighting fixtures. The first prong, or top-down approach, estimates the upper limit of optimal productivity by introducing system inefficiencies into the productivity frontier—the productivity achieved under perfect conditions. This study uses a qualitative factor model to identify this upper limit. The second prong, or bottom-up approach, es...

The paper presents the optimization method of turbine stages based on step-by-step application of onedimensional and three-dimensional optimization techniques of the main stage geometrical parameters. Using the developed method, the optimization of the 3rd stage of high pressure steam turbine K-540-23.5 was carried out. As a result of optimization a new stage with an absolute efficiency increase more than 1% compared to the original design was obtained. The reasons leading to such performance boost were analyzed and are represented in the paper.

Ion beam induced luminescence has been used to study the response of scintillator screens of YO:Eu (P56) and SrGaS:Eu (TG-Green) when irradiated with light ions (protons, deuterium and helium particles). The absolute efficiency of the samples has been studied as a function of the ion energy (with energies up to 3.5 MeV), the beam current and the operating temperature. The evolution of the scintillator yield with ion fluence has been carried out for all the scintillators to estimate radiation damage. Finally, measurements of the decay time of these materials using a system of pulsed beam accelerated particles have been done. Among the screens under study, the TG-Green is the best suited material, in terms of absolute efficiency, temporal response and degradation with ion dose, for fast-ion loss detectors in fusion devices., This research was supported in part by the Spanish Ministry of Economy and Competitiveness through the projects RYC-2011-09152, ENE2012-31087 and FIS2015-69362-P (MINECO/FEDER, UE) and the Marie Curie FP7 Integration Grant (No. PCIG11-GA-2012-321455) and the V Plan propio de la Universidad de Sevilla (VPPI-US).

Mechanically stacked solar cells formed using adhesive bonding are proposed as a route to high-efficiency devices as they enable the combination of a wide range of materials and bandgaps. The concept involves adhesive bonding of subcells using polymeric materials widely used in semiconductor processing and outlines how the absolute efficiency can be maximised by optimisation of the adhesive layer thickness and optical matching of the adhesive layer with both the subcells and their anti-reflection coatings. A dual-junction, GaAs-InGaAs, mechanically stacked solar cell is demonstrated using a benzocyclobutene adhesive layer with a measured PV conversion efficiency of 25.2% under 1-sun AM1.5G conditions. Copyright © 2014 John Wiley & Sons, Ltd.

Mixed gamma-ray point sources consisting of 152Eu and 154Eu were prepared from a solution of EuCl3 containing both isotopes. Gamma-rays emitted from these isotopes were used to establish the relative efficiency curves of HPGe detector, which were converted to absolute ones using gamma-ray sources of well-known activities. Gamma-ray attenuation correction factors were taken into account. Accuracies of activity measurements of the prepared sources were checked by measuring other sources of well-known activities and confirmed by simulating the absolute efficiency curve at distance of 15 cm from the detector window using the DETEFF software. The prepared sources were then submitted to quality control tests.

A study on the optimisation of front contacts of n-type multicrystalline silicon solar cells is presented. In this study the same cell processing was applied to two types of wafers: electronic grade (EG-Si) and metallurgic grade (MG-Si) silicon. The contact firing temperature was optimised, by measuring the contact resistivity of the front and back contacts for different firing temperatures. The front contacts were improved by deposing silver using an electrochemical process. The solar cells were characterised before and after the silver deposition. For all cells processed the line resistance was reduced by over 90% after the silver deposition. After the contact improvement, EG-Si cells showed an absolute efficiency improvement of 2.6%, but MG-Si cells suffered a reduction on the cell efficiency, an effect related to parasitic shunting existent in these cells.

In this study, we detail a Cu2ZnSnSe4 based solar cell fabrication process based on the selenization of metallic precursor stacks with elemental Se. 9.4% efficient devices without antireflection coating have been obtained. First, reproducibility issues of the process are carefully shown and discussed. It is demonstrated that device performances are strongly impacted by the precise control of the precursor composition. Then, starting from this robust process, a review of existing strategies to improve kesterite efficiencies is conducted. A significant increase in efficiency (+1.4% absolute efficiency and +50 mV VOC) is obtained with absorber surface treatment and post-annealing, while no effect of Ge incorporation in the precursor stack is observed. This contradictory result to most of the recent publications raises the question of the universality of this strategy to improve kesterite solar cell performance. Finding a universal activation step to boost kesterite efficiencies and bring it to the market remains a crucial need for the community.In this study, we detail a Cu2ZnSnSe4 based solar cell fabrication process based on the selenization of metallic precursor stacks with elemental Se. 9.4% efficient devices without antireflection coating have been obtained. First, reproducibility issues of the process are carefully shown and discussed. It is demonstrated that device performances are strongly impacted by the precise control of the precursor composition. Then, starting from this robust process, a review of existing strategies to improve kesterite efficiencies is conducted. A significant increase in efficiency (+1.4% absolute efficiency and +50 mV VOC) is obtained with absorber surface treatment and post-annealing, while no effect of Ge incorporation in the precursor stack is observed. This contradictory result to most of the recent publications raises the question of the universality of this strategy to improve kesterite solar cell performance. Finding a universal activation step to boost kesterite efficiencies and bring it to the market rem...