bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation and Characterization of Cu-Ga-Se Films of Ordered Vacancy Compound
Authors: Nishiwaki S. , Siebentritt S. , Lux-Steiner M. Ch. 
Published: May 2017

AbstractCu-Ga-Se films with an orderd vacancy compound (OVC) structure were prepared at substrate temperature about 500 °C by thermal co-deposition. With a preparation under extremely Se excess condition, films of the OVC were synthesized within the compositional ratio of 0.73 ≤ [Ga]/([Cu]+[Ga]) ≤ 0.86 along Cu2Se-Ga2Se3 pseudo binary system. The growth on soda-lime glass substrates improves the crystallinity compared to that on alkali-free glass. An increase in the optical bandgaps of OVC films from 1.85 eV to 1.94 eV was observed with an increase in the Ga content of the films. The deposition of Cu and Se onto Ga2Se3 films resulted in a vertically inhomogeneous film: the bottom layer with the OVC structure and the top layer with the chalcopyrite structure. A solar cell using the CuGa5.0Se8.1 film within a ZnO/CdS/CuGa-Se/Mo/soda-lime glass substrate structure showed an open circuit voltage of 947 mV, an efficiency of 2.2 %, a short circuit current density of 4.5 mA/cm2, and a fill factor of 0.52 (Air Mass 1.5, 0.5 cm2, total area).
Evolution of Electronic Properties of Cu(In, Ga)Se2 (CIGS)-Based Solar Cells During a 3-stage Growth Process
Authors: AbuShama Jehad A. , Johnston S. , Ahrenkiel R. , Crandall R. , Young D. , Noufi R. 
Published: May 2017

AbstractWe investigated the electronic properties of ZnO/CdS/CIGS/Mo/SLG polycrystalline thin-film solar cells with compositions ranging from Cu-rich to In(Ga)-rich by deep-level transient spectroscopy (DLTS) and capacitance-voltage (C-V) measurements. This compositional change represents the evolution of the film during growth by the 3-stage process. Two sets (four samples each) of CIGS thin films were prepared with Ga/(In+Ga) ratios of ∼0.3 (low Ga) and ∼0.6 (high Ga). The Cu/(In+Ga) ratio ranges from 1.24 (Cu-rich) to 0.88 (In(Ga)-rich). The films were treated with NaCN to remove the Cu2-xSe phase where needed. Key results include: (1) For lowGa devices, DLTS data show that acceptor-like traps dominate in samples where CIGS grains do not go through the Cu-rich to In(Ga)-rich transition, whereas donor-like traps dominate in In(Ga)-rich samples. Therefore, we see a clear transformation of defects from acceptor-like to donor-like traps. The activation energies of these traps range from 0.12 to 0.63 eV. We also observed that NaCN treatment eliminates a deep minority trap in the In(Ga)-rich devices, (2) For high-Ga devices, only majority-carrier traps were detected. These traps again range from shallow to deep, (3) The carrier concentration around the junction and the density of traps decrease as the CIGS becomes more In(Ga)-rich.
Formation Energies of Point Defects in Copper Indium Diselenide Using ab initio Methods
Authors: Domain C. , Raulot J.M. , Laribi S. , Taunier S. , Guillemoles J.F. 
Published: May 2017

AbstractThe opto-electronic properties of CuInSe2 and related compounds depend on their defect chemistry in a way that is far from being understood and in which ab initio calculations could help by providing new insights as shown previously. Ab initio calculations of energy and electronic structure of various intrinsic (including defect pairs) and extrinsic (including potential dopants such as Zn) point defects have been performed in the chalcopyrite semiconductors CuInSe2, some of them being computed for the first time by advanced ab initio techniques. The method used is based on the density functional theory within the framework of pseudo-potentials and plane waves basis set. The results are discussed in view of the existing data, models and calculations.
Modification of Cu(In, Ga)Se2 Surface by Treatment in Cadmium Solutions
Authors: Nguyen Q. , Bilger G. , Rau U. , Schock H.W. 
Published: May 2017

AbstractThis article investigates chemical modifications of Cu(In, Ga)Se2 thin film by treatment in cadmium solutions with varying [NH3] concentration. Secondary ions mass spectroscopy and Xray photoelectron-spectroscopy analysis show that Cd-diffusion into the Cu(In, Ga)Se2 film is intimately tied to the reduction-oxidation of the Cu(In, Ga)Se2 surface, which is controlled by the [NH3] concentration. Reaction products, like Se and metal hydroxides of the redox process as wellas thediffusedCdinCu(In, Ga)Se2 film, result in degradation of solar cell performance.
Measurement of Built-in Electrical Potential in Cu(In, Ga)Se2 Solar Cells
Authors: Jiang C.-S. , Hasoon F.S. , Moutinho H.R. , Al-Thani H.A. , Romero M.J. , Al-Jassim M.M. 
Published: May 2017

AbstractThe built-in electrical potential on cross sections of Cu(In, Ga)Se2 (CIGS) solar cells was measured quantitatively and resolved spatially using scanning Kelvin probe microscopy. In the conditions of open and short circuits, no significant potential variation on the p-n junction was probed due to the surface Fermi-level pinning. With an external reverse-bias voltage applied to the device, we were able to probe the potential on the junction; the potential profiles demonstrate that the p-n junction is a buried homojunction, located 30-80 nm from the CIGS/CdS interface in the CIGS film. The potential measurement over the CdS and ZnO layers, which is consistent with the band diagram calculations, indicates that the CdS and ZnO layers are inactive for the collection of photoexcited carriers.
Nucleation of Cu(In, Ga)Se2 on Molybdenum Substrates
Authors: Schlenker T. , Orgassa K. , Schock H. W. , Werner J. H. 
Published: May 2017

AbstractWe investigate growth mechanisms of Cu(In, Ga)Se2 on Mo films on glass, as the typical back contact for Cu(In, Ga)Se2 solar cells. A thermal evaporation process deposits Cu(In, Ga)Se2of nominal 3 nm thickness at different rates R and substrate temperatures TSub. An ultrahigh resolution scanning electron microscope serves to investigate the nucleation behavior. The deposited Cu(In, Ga)Se2 forms three-dimensional isolated nuclei, known as Volmer-Weber growth mode. Deposition rate R and substrate temperature TSub control the areal density n of the Cu(In, Ga)Se2 nuclei. We observe a power law dependence between the island density n and the deposition rate R, and an exponential dependence of the island density n on substrate temperature TSub. The theory of homogeneous nucleation explains the Cu(In, Ga)Se2 cluster formation on polycrystalline Mo and the dependence of the island density on the growth conditions.
Photoconductive CdS: how does it Affect CdTe/CdS Solar Cell Performance?
Authors: Hegedus S. , Ryan D. , Dobson K. , McCandless B. , Desai D. 
Published: May 2017

AbstractPhotoconductive CdS (PC-CdS) in CdS/CdTe solar cells from five different sources is investigated using spectral sensitization of apparent quantum efficiency (AQE) and J-V analysis. Red bias light significantly enhances the blue AQE, commonly leading to AQE>1 below 550 nm, and blue bias light enhances the red AQE, but to a much smaller extent. These enhancements are more pronounced with increasing forward bias, after stress and in devices with intentionally Cu-doped CdS. This behavior is observed to some degree in all devices with CdS, but is absent in cells without CdS. These effects are consistent with blue light, either ac monochromatic or dc bias, increasing the CdS conductivity. This causes an increase in the field and depletion width in the CdTe to maintain balanced space charge, leading to increased collection of carriers from the CdTe. The CdS conductivity modulation can also change the AQE due to a change in equivalent circuit resistance. Analysis of J-V data measured with white, blue, red or no light indicates little dependence of series resistance or diode quality factor on the illumination spectrum. Thus, the PC-CdS resistance has little effect on the solar cell J-V performance, but does influence AQE.
Qualidade de vida das pessoas que vivem com o HIV/aids: estudo transversal
Authors: Hipolito Rodrigo Leite , De Oliveira Denize Cristina 
Published: May 2017

Objetivo: analisar a qualidade de vida (QV) e suas representações em momentos distintos de diagnóstico. Método: estudo descritivo, transversal, com amostra estratificada pelo tempo de diagnóstico composta por 100 pessoas soropositivas de serviço especializado em município da baixada litorânea fluminense. Utilizaram-se formulários sociodemográfico e de saúde, seguido pelo WHOQOL-HIV Bref e entrevista semiestruturada. Empregou-se análise estatística descritiva e inferencial. A análise lexical foi operacionalizada pelo software Alceste. Resultados: a percepção da QV foi intermediária em todos os domínios, bem como os conteúdos da representação da QV apontaram para a hipótese de representação não autônoma em relação à representação social da aids. Conclusão: constatou-se um perfil representacional da qualidade de vida tendente para aspectos positivos e de ressignificação, apoiados nas novas simbologias atribuídas ao objeto aids. É necessário considerar a satisfação com a saúde e o maior tempo de diagnóstico no domínio físico como aspectos pertinentes ao cuidado de enfermagem.
Etudes de terrain sur la fièvre catarrhale ovine et la maladie hémorragique épizootique en Turquie
Authors: Ertürk A. , Cizmeci S. G. , Barut M. F. , Allepuz Alberto , Alba Anna , Napp Sebastian , Casal Jordi 
Published: May 2017

The objective of this study was to detect the presence of new serotypes of bluetongue (BT) circulating in Turkey. A cross-sec­tional study was conducted between March and May 2008 in the provinces of Adana, Mersin, Antalya, Osmaniye, and Hatay (Mediterranean region). The serosurvey was only performed in cattle. This species was not vaccinated and the presence of an­tibodies would indicate that the animal had been infected by field strains of BT virus. Only animals born after the outbreaks were sampled. The epidemiological unit was the village, which was the lowest level for which census data was available. Ran­dom sampling was carried out in 146 villages and eight sam­ples were collected in each village. A competitive enzyme-linked immunosorbent assay (cELISA) was used for detection of BT antibodies. Preliminary results of the study were presented. From a total of 1096 serum samples collected, 352 (32.1%) were positive to BT. The seroprevalence by province ranged from 15% in Antalya (45/257) to 88% in Osmaniye (77/88). In animals under two years old, the sero­prevalence was 25%, whereas in adult animals it was 52%. The differences in the seroprevalence detected between the five provinces could be attributed to the different density of vector, cattle and small ruminant populations. The high seroprevalence in unvaccinated cattle indicated that BT infection was wide­spread in the ruminant population of Turkey. The young animals presented a lower prevalence than the adults, suggesting that the adults had probably been exposed to the virus before the last two years, whereas the presence of positive seroconversion in young animals indicated that BT virus had been circulating in the two-year period.
Programme national bulgare de surveillance du virus de la fièvre catarrhale : études de terrain et évaluation du risque en 2009
Authors: Georgiev G. , Nedelchev N. , Polihronova L. 
Published: May 2017

Bluetongue is a non-contagious, arthropod-borne viral disease of both domestic and wild ruminants. Bluetongue virus (BTV) is endemic in some areas where cattle and wild ruminants serve as reservoirs for the virus. Some authors suggest that a fundamental change in the European ecosystem since 1998, mostly linked to climate change, may have influenced the introduction and sur­vival of BTV in Europe. Genetic analyses of bluetongue viruses isolated in Europe during this period showed that six virus types (1, 2, 4, 8, 9 and 16) have entered the region since that period. The aim of this presentation was to summarize the results of the National BTV Surveillance Programme, field studies, and risk assessment of BTV entry into Bulgaria in 2009. As part of the Surveillance Programme of the disease in 2009, seroprevalence was performed in 19 sentinel BTV-seronegative animal herds, 7 of which were located in the western part of the country and the other 12 in the southern part, about 10 to 20 kil­ometres from the border. Each sentinel herd consisted of 10 large ear-tagged ruminants. The sentinel animals were tested every 30 days for the presence of BTV antibodies. Competitive enzyme-linked immunosorbent assays (cELISAs) were used to determine the antibodies against the common group antigen. Fourteen Onderstepoort black light traps were set up for Culicoides surveil­lance and monitoring in southern and western border districts of the country after April 1, 2009. Catches of Culicoides were sorted by traditional identification keys. The risk of BTV invasion was assessed according to the World Organisation for Animal Health standards. The hazard identification, possibility of BT outbreaks, and assessment of the epidemiological situation in neighbour­ing countries were made based on other authors’ reports on the density of small and large ruminants, and economical and trade relations between countries. In addition, the BTV situation on a Greek Aegean Sea Island was closely monitored in 2008-09. During the 2009 serum surveillance period, 3340 serum sam­ples from different species of ruminants were investigated, all with negative results for BTV antibodies; C. imicola was never detected in more than 12 years of Culicoides surveillance in Bulgaria. Analysis of 274 midges caught during 2009 showed that dominating Culicoides species were of the Obsoletus and Pulicaris complexes, well-known Palaearctic midges in Europe. The negative results from the Surveillance Programme supported the evidence of absence of active BTV circulation on the whole territory of Bulgaria during 2009. During the 2008-09 season, Greek Authorities reported several circulating BTV serotypes (1, 8, 16) on Lesvos Island. As the epidemiological situation on Greek islands in the Aegean Sea is complicated and not very clear, the risk of BTV entering Bulgaria ranges from high (in spring and summer) to moderate (in winter and autumn).
Base de données sur Internet et système d'information géographique pour appuyer Medreonet
Authors: Savini L. , Ippoliti C. , Di Lorenzo I. , Conte Anna Amaria 
Published: May 2017

The main objective of Medreonet is to share and exchange data, expertise, experiences and information on bluetongue (BT), African horse sickness (AHS) and epizootic haemorrhagic disease (EHD). In this context the web-based database and geographical information system (GIS) application is the most suitable tool to provide a friendly environment that is easy to use by the different actors involved in the project. The web-based database and GIS application has been developed using ESRI software (release 9.0) (ArcIMS, ArcGIS desktop, ArcSDE), Java and Active Server Pages (ASP). Users can access the public web-GIS through a generic Internet browser and the information required (maps and data) are published by ArcIMS using web server technology. ArcSDE and an Oracle relational database management system (release 8i) (RDBMS) are used to store and manage spatial and alphanumerical data. The authorized users can input new information and data on their geographical area of competence directly online, using ASP and a web interface. The accuracy of the data entered into the information system (e.g. missing values, duplicates, incorrect data format, etc.) is guaranteed by automatic check procedures that operate dur­ing the updating of the centralized database. The database was designed to store all the epidemiological data deemed relevant by the experts and all the scientific results, when available, pro­duced during the project. In particular, the data collected cover three main sets of information which are displayed and spread through an interactive, dynamic mapping system: – outbreak distribution, i.e. the geographical distribution of the disease by year and serotype at the regional level in the European Union (EU) and Mediterranean countries for BT, AHS, and EHD, respectively; – serological surveillance results, i.e. geographical distribution of the true and apparent prevalence of infection based on the analyses of BT serological surveillance data; – entomological distribution, i.e. geographical distribution of nine vector species by year and month, number of catch sites, number of catches, vector and maximum number of midges at the regional level in the EU and Mediterranean countries. Medreonet database and GIS application fulfill all the require­ments stipulated in the project; moreover the system is fully scalable and may adapt to future demands.
Le portail SIGLA – un système d'information géographique sur Internet pour le programme portugais de surveillance entomologique de la fièvre catarrhale ovine
Authors: Martins H. , Nunes T. , Boinas Fernando 
Published: May 2017

Bluetongue (BT) is an infectious non-contagious disease, whose transmission is commonly associated with an intermediate arthropod host from the Culicoides genre. A BT entomologi­cal surveillance programme was implemented in Portugal in May 2005 to collect data on the abundance, and spatial and temporal distribution of several species potentially involved in the transmission of the disease. At that time a simple local alphanumerical relational database was built to record all data. Although it fulfilled the initial objectives of data management, there was an increasing need to share this information in real-time with national veterinary authorities. Moreover, sharing this data in a map-based approach was not possible without con­siderable time-consuming effort. To overcome these needs, a new web-based system with geographical information system (GIS) capabilities was designed and is currently being devel­oped exclusively using Open Source Software (Portal SIGLA). The alphanumerical component was partially migrated from the previous system, though introducing query capabilities visually supported by the use of dynamic charts further enriched it. The geographical component is now the development core, but it already contains several tools of a standard web mapping application (zooming, panning, distance and area measure­ments, activation/deactivation of spatial layers, legend panel, graphical and numerical scale…). This enterprise-level relational database with geographical functions also makes spatial editing available through the web and thus enables technicians with no GIS expertise to create and handle easily spatial data. The system democratizes GIS technology and provides veterinary officers with real-time data sharing. It helps to gain further insight into disease dynamics and thus to contribute to more effective sani­tary control measures. Future developments are mainly related to spatial querying of data through the form of choropleth and chart maps. This will further enrich the analysis capabilities of the system.
Situation actuelle de la fièvre catarrhale ovine en Europe et dans le bassin méditerranéen
Authors: Mesman S. 
Published: May 2017

In the past, only sporadic incursions of bluetongue (BT) occurred, mainly in Southern Europe. The disease showed a tendency to disappear naturally, probably because the necessary climatic, environmental and entomological conditions to ensure virus spread and persistence did not occur. The situation has how­ever changed dramatically in the last decade. Until three years ago, the disease mainly affected the Mediterranean Basin. Since fall 2006 new serotypes have emerged and the unprecedented spread of BTV-1 and BTV-8 caused outbreaks in many countries of the European Union (EU). The EU Commission responded to the changing BT disease situ­ation by developing continuous finely-tuned EU-legislation in close cooperation with EU Member States, and by allocating funding to implement vaccination programmes in the States. EU rules on BT are highly influenced by changes in the disease situ­ation, experiences in the Member States, results of the ongoing data gathering, and research on BT disease and its vectors. The European Food Safety Authority (EFSA) is the risk assessor and produces scientific opinions and advice to provide a sound basis for European policies and legislation. Also, the EU Commission has ensured considerable financial support to the vaccination programmes that have been put in place in several Member States for the years 2007 and 2008. Community rules on BT lay down general provisions for the control and eradication of BT, as well as detailed rules on disease control, monitoring, surveillance and restrictions on movements of susceptible animals. All BT outbreaks must be notified by EU Member States to the Animal Disease Notification System (ADNS). In addition, information that has been gathered in the course of implementing BT monitoring and/or surveillance programmes must be transmitted to BT-Net system. Monthly, six-monthly and annual reports are required. Data and maps can be viewed on BT-Net:http://eubtnet.izs.it/btnet/reports/ EpidemiologicalSituation.html The Standing Committee on the Food Chain and Animal Health (SCoFCAH) plays a key role in the EU decision-making process. Representatives of EU Member States meet on a monthly basis with the European Commission. Updates on the epidemiological situation of BT (and other animal diseases) are presented by the Member States (presentations are available on SANCO web­page). The EU Commission consults SCoFCAH on new proposals for an opinion after which the measure can be formally adopted in accordance with the appropriate procedure. With the support of the Member States experts in the technical working groups and the representatives at SCoFCAH, Regulation (EC) No 1266/2007 has been amended several times to respond better to the evolving disease situation. Together with appropri­ate surveillance and restrictions on animal movements, mass vaccination of all susceptible and reachable animals in the restricted zones with all available vaccines is currently the pre­ferred option as regards effective BT control.
GOOD LANGUAGE LEARNERS AND THEIR STRATEGIES: AN INSIGHT
Authors: Mahalingam Kumaresen , Md. Yunus Melor 
Published: May 2017

The Malaysian Education Blueprint is aimed to ensure every child is proficient in English Language besides Bahasa Malaysia. Thus the English Language syllabus is geared to mould learners to become successful language learners. However, not all learners are capable of being successful language learners despite years of schooling. Therefore, this study aims to investigate language learning strategies used by good language learners in learning English as their second language. To achieve the aim of the study, a questionnaire was used to collect the quantitative data. 30 pupils with good language ability from a rural primary school in Sabah were selected to participate in this study. The findings of the study indicated that different language learners prefer different learning strategies to improve their second language learning. The learning strategies also vary based on the language skills they are learning. The findings of the study are hoped to provide significant impact to the pupils, teachers and curriculum planners to integrate language learning strategies in teaching and learning to assist successful language learning.