2,924 research outputs found

    Influence of compositionally induced defects on the vibrational properties of device grade Cu2ZnSnSe4 absorbers for kesterite based solar cells

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    This work presents a detailed analysis of the impact of compositionally induced defects on the vibrational properties of Cu2ZnSnSe4 absorbers for kesterite based solar cells. Systematic changes in the intensity of the E and B modes located around the 170, 220, and 250 cm-1 frequency regions, which involve mostly cation vibrations, were observed and analyzed in relation to the occurrence of different kinds of defect clusters involving VCu, ZnCu, ZnSn, CuZn, and SnZn point defects. Additional changes are also interpreted in terms of the appearance of SnSe, ZnSe, and CuSe-like contributions at the 185 and 250 cm-1 spectral regions, respectively. The sensitivity of the Raman measurements to the presence of these kinds of defects corroborates the potential of Raman scattering for point defect assessment in these systems. © 2015 AIP Publishing LLCPeer ReviewedPostprint (published version

    "There's no kind of respect here" A qualitative study of racism and access to maternal health care among Romani women in the Balkans

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    <p>Abstract</p> <p>Introduction</p> <p>Roma, the largest minority group in Europe, face widespread racism and health disadvantage. Using qualitative data from Serbia and Macedonia, our objective was to develop a conceptual framework showing how three levels of racism--personal, internalized, and institutional--affect access to maternal health care among Romani women.</p> <p>Methods</p> <p>Eight focus groups of Romani women aged 14-44 (n = 71), as well as in-depth semi-structured interviews with gynecologists (n = 8) and key informants from NGOs and state institutions (n = 11) were conducted on maternal health care seeking, experiences during care, and perceived health care discrimination. Transcripts were coded, and analyzed using a grounded theory approach. Themes were categorized into domains.</p> <p>Results</p> <p>Twenty-two emergent themes identified barriers that reflected how racism affects access to maternal health care. The domains into which the themes were classified were perceptions and interactions with health system, psychological factors, social environment and resources, lack of health system accountability, financial needs, and exclusion from education.</p> <p>Conclusions</p> <p>The experiences of Romani women demonstrate psychosocial and structural pathways by which racism and discrimination affect access to prenatal and maternity care. Interventions to address maternal health inequalities should target barriers within all three levels of racism.</p

    Scalable heating-up synthesis of monodisperse Cu2ZnSnS4 nanocrystals

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    Monodisperse Cu2ZnSnS4 (CZTS) nanocrystals (NCs), with quasi spherical shape, were prepared by a facile, high-yield, scalable, and high-concentration heat-up procedure. The key parameters to minimize the NC size distribution were efficient mixing and heat transfer in the reaction mixture through intensive argon bubbling and improved control of the heating ramp stability. Optimized synthetic conditions allowed the production of several grams of highly monodisperse CZTS NCs per batch, with up to 5 wt % concentration in a crude solution and a yield above 90%

    Мерење масе W бозона и калибрација импулса миона на детектору АТЛАС

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    U ovoj tezi je opisano meree mase W bozona, koje se zasniva na podacima prikup enim na detektoru ATLAS tokom 2011. godine u proton{proton sudarima na energiji od 7 TeV na Velikom sudaraqu hadrona (LHC). Prema Standardnom modelu masa W bozona zavisi od mase top kvarka i mase Higsovog bozona kroz korekcije vixeg reda. Preciznim mereem mase top kvarka, W i Higsovog bozona mogue je testirae konzistentnosti Standardnog modela, i bilo koje neslagae predstav a indirektan dokaz postojaa qestica izvan Standardnog modela. Masa W bozona je preth- odno izmerena na eksperimentima na Velikom eletron{pozitronskom su- daraqu, kao i na eksperimentima CDF i D0 na proton{antiproton su- daraqu Tevatron. Trenutna sreda vrednost izmerene mase W bozona iznosi mW = 80385 15 MeV, dok je najpreciznije meree ostvareno na eksperimentu CDF sa neodreenoxu 19 MeV. Sa druge strane, na osno- vu globalnog fita parametara Standardnog modela predviena masa W bozona iznosi mW = 80358 8 MeV...In this thesis measurement of the W-boson mass based on data collected during 2011 in proton–proton collisions at a centre-of-mass energy of 7 TeV with the ATLAS detector at the Large Hadron Collider (LHC) is presented. In the Standard Model, the Wboson mass depends on the top quark mass and the Higgs-boson mass through higher order corrections. Therefore, a precise measurements the mass of the top quark, Wand Higgs-boson, provide a stringent test of the Standard Model. Any observed inconsistency can be an indirect proof of the physics beyond the Standard Model. Previous measurements of the mass of the W boson are performed at the Large electron–positron collider, and at the Tevatron proton–antiproton collider with the CDF and D0 experiments. The current world average value of the W-boson mass is mW = 8038515 MeV, while the most precise single measurement with an uncertainty of 19 MeV is performed with the CDF experiment. On the other hand, the indirect constraint on the W-boson mass from the global electroweak fit predicts mW = 80358 8 MeV..

    The certification of different mass fractions of MON-Ø4Ø32-6 in soya bean powder Certified Reference Materials ERM®-BF410ap, ERM®-BF410bp, ERM®-BF410cp, ERM®-BF410dp and ERM®-BF410ep

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    This report describes the production of a set of Certified Reference Materials (CRMs), ERM BF410ap, bp, cp, dp and ep, which are certified for their GTS 40-3-2 soya bean (unique identifier MON-Ø4Ø32-6) event mass fractions. These materials were produced following ISO Guide 34:2009 and are certified in accordance with ISO Guide 35:2006. The materials are intended for the calibration or quality control of real-time PCR measurements to identify GTS 40-3-2 soya bean and quantify its mass fraction. As with any reference material, they can also be used for establishing control charts or for carrying out validation studies. The CRMs were accepted as European Reference Material (ERM®) after peer evaluation by the partners of the European Reference Materials panel.JRC.F.6-Reference Material

    Influence of compositionally induced defects on the vibrational properties of device grade Cu2ZnSnSe4 absorbers for kesterite based solar cells

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    This work presents a detailed analysis of the impact of compositionally induced defects on the vibrational properties of Cu2ZnSnSe4 absorbers for kesterite based solar cells. Systematic changes in the intensity of the E and B modes located around the 170, 220, and 250 cm 1 frequency regions, which involve mostly cation vibrations, were observed and analyzed in relation to the occurrence of different kinds of defect clusters involving VCu, ZnCu, ZnSn, CuZn, and SnZn point defects. Additional changes are also interpreted in terms of the appearance of SnSe, ZnSe, and CuSe-like contributions at the 185 and 250 cm 1 spectral regions, respectively. The sensitivity of the Raman measurements to the presence of these kinds of defects corroborates the potential of Raman scattering for point defect assessment in these systems

    CERTIFICATION REPORT The certification of different mass fractions of VCO-Ø1981-5 in maize seed powder Certified Reference Materials ERM®-BF438a, ERM®-BF438b, ERM®-BF438c, ERM®-BF438d and ERM®-BF438e

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    This report describes the production of a set of Certified Reference Materials (CRMs) ERM BF438a, b, c, d and e, which are certified for their VCO-Ø1981-5 mass fractions. These materials were produced following ISO Guide 34:2009 and are certified in accordance with ISO Guide 35:2006. Genetically modified (GM) seeds of the maize event VCO-Ø1981-5 and seeds from a non-GM maize variety were milled to obtain GM and non-GM seed powders with a similar particle size distribution. Mixtures of non-GM and GM maize powder were prepared gravimetrically. The certified value was obtained from the gravimetric preparations, taking into account the genetic purity with respect to the event VCO-Ø1981-5 of the two powder materials and their water mass fractions. The certified values were confirmed by event-specific real-time PCR as an independent verification method (measurements were within the scope of accreditation to ISO/IEC 17025:2005). The uncertainties of the certified values were estimated in accordance with the Guide to the Expression of Uncertainty in Measurement (GUM) [4] and include uncertainties relating to possible inhomogeneity (Section 4), instability (Section 5) and characterisation (Section 6). The materials are intended for the calibration or quality control of real-time PCR measurements to identify VCO-Ø1981-5 maize and/or quantify its mass fraction. As with any reference material, they can also be used for establishing control charts or for carrying out validation studies. The CRMs are available in glass bottles containing at least 1 g of dried maize seed powder, which were sealed under atmosphere of argon. The minimum amount of sample of the mixtures to be used and recommend for the blank and pure VCO-Ø1981-5 materials is 200 mg. The CRMs were accepted as European Reference Material (ERM®) after peer evaluation by the partners of the European Reference Materials consortium.JRC.D.2-Standards for Innovation and sustainable Developmen

    CERTIFICATION REPORT: The certification of different mass fractions of Bt11 in maize powder: Certified Reference Materials: ERM®-BF412ak, ERM®-BF412bk, ERM®-BF412ck, ERM®-BF412dk and ERM®-BF412ek

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    This report describes the production of a set of Certified Reference Materials (CRMs), ERM-BF412ak, bk, ck, dk and ek, which are certified for their Bt11 maize (unique identifier SYN-BTØ11-1) event mass fractions. These materials were produced following ISO Guide 34:2009 and are certified in accordance with ISO Guide 35:2006. Genetically modified (GM) maize seeds of the Bt11 event and seeds from a non GM maize variety were milled to obtain GM and non-GM seed powders with a similar particle size distribution. Mixtures of non-GM and GM maize seed powder were prepared gravimetrically. The certified values were obtained from the gravimetric preparations, taking into account the water mass fractions of the two powder materials and the genetic purity with respect to the Bt11 maize. The certified values were confirmed by event-specific real-time PCR as an independent verification method (measurements were within the scope of accreditation to ISO/IEC 17025:2005). The uncertainties of the certified values were estimated in accordance with the Guide to the Expression of Uncertainty in Measurement (GUM) and include uncertainties relating to possible inhomogeneity (Section 4), instability (Section 5) and characterisation (Section 6). The materials are intended for the calibration or quality control of real-time PCR measurements to identify Bt11 maize and quantify its mass fraction. As with any reference material, they can also be used for establishing control charts or for carrying out validation studies. The CRMs are available in glass bottles containing at least 1 g of dried maize seed powder, sealed under an atmosphere of argon. The minimum amount of sample to be used for extraction of the DNA is 200 mg.JRC.F.6-Reference Material

    The certification of different mass fractions of the GM event 73496 in rapeseed powder: Certified Reference Materials ERM®-BF434a, ERM®-BF434b, ERM®-BF434c, ERM®-BF434d and ERM®-BF434e

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    This report describes the production of the set of Certified Reference Materials (CRMs) ERM-BF434a, b, c, d and e. These are matrix materials certified for their 73496 rapeseed mass fractions. The material has been produced following ISO Guide 34:2009. Genetically modified (GM) rapeseeds of the event 73496 and of a non-GM rapeseed variety were ground to obtain GM and non-GM base powders. Gravimetric mixtures of non-GM and GM rapeseed powder were prepared by dry-mixing. The between unit-heterogeneity has been quantified and stability during dispatch and stability during storage have been assessed in accordance with ISO Guide 35:2006. The certified value was obtained from the gravimetric preparations, taking into account the purity of the base materials and their respective water mass fraction. The certified values were confirmed by event-specific real-time PCR as an independent verification method (measurements within the scope of accreditation to ISO/IEC 17025:2005). Uncertainties of the certified values were calculated in compliance with the Guide to the Expression of Uncertainty in Measurement (GUM) and include uncertainties related to possible inhomogeneity (Section 4), instability (Section 5) and characterisation (Section 6). The materials are intended for the calibration or quality control of 73496 rapeseed identification and quantification methods. As any reference material, they can also be used for control charts or validation studies. The CRMs are available in glass vials containing at least 1 g of dried rapeseed powder closed under argon atmosphere. The minimum amount of sample to be used is 200 mg. The CRM has been accepted as European Reference Material (ERM®) after peer evaluation by the partners of the European Reference Materials consortium.JRC.D.2-Standards for Innovation and sustainable Developmen
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