Sorption-enhanced Fischer-Tropsch synthesis – Effect of water removal

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Characterization of boron-coated silicon sensors for thermal neutron detection

Silicon neutron detectors can operate at low voltage and come with ease of fabrication and the possibility of integration of readout electronics and thus are attractive from an application point of view. In this paper, we have studied thermal neutron capture by silicon diodes coated with boron carbide (B4C). One of the surfaces of the diodes was covered with either natural B4C (B4C) or with enriched B4C (B4C). We have investigated: (a) the effect of increase in the sensitive area of the surface of the diode covered with B4C on the neutron detection efficiency and (b) the effect of enrichment of 10B in B4C. The difference in 10B in B4C (16 at.% in the deposited film) and B4C ( 79 at.% in the deposited film) leads to about three times increase in detection efficiency of the same detector. For the given experimental conditions, we do not observe a direct relationship between increase in the surface area and the detection efficiency. Energy spectra obtained by Geant4 simulations support the experimental observation of finding no direct relation between increase in the surface area and the detection efficiency.publishedVersio

"Who am I? Where am I?" Experiences of married young women in a slum in Islamabad, Pakistan

Background: According to the cultural tradition in Pakistan, young women belonging to poor families should marry shortly after menarche. However, existing data show that young people, especially women, are not prepared for sexual life and have poor knowledge about sexuality and reproductive health. Many of the difficulties young women experience are related to beliefs and expectations in the society related to their reproductive roles making them more vulnerable to reproductive ill health. Aim: The study explores the preparedness of young women for married life (communicating with spouse, initiation of sexual activity and child bearing) and ability to negotiate in marriage with spouse on number of children to have and on contraceptive use. Methods: In order to obtain an in-depth understanding of young women’s lives qualitative and quantitative approaches were used. Three qualitative studies using narrative and content analysis were carried out in a slum setting in the outskirts of Islamabad city in Pakistan. Married young women (I), unmarried young women (II) and parents (III) were selected with the help of a community worker. Young married women were interviewed three times at different occasions. Narrative structuring was used to explore how the participants represented their situation. In addition twenty qualitative interviews and three focus group discussions were conducted with young unmarried women (II). Twenty-five parents participated in four gender specific focus group discussions (III). Content analysis was used for analysis of study II and III. For the quantitative study (IV), a subset of 1803 married young women aged 15-24 years was drawn from a nationally representative adolescent and youth survey conducted in Pakistan in 2001-2002 by the Population Council. Regression models were used for analysing the following outcomes: reported agreement with spouse on the number of children to have, current use of contraceptives, intention to use contraceptives in the future and the time elapsed between marriage and the first contraceptive use. Key co-variates of interest were variables that measure the involvement of young women in their marriage as having a say in selection of spouse, mobility outside the household, social role and decision making in their homes. Results: The main theme in all the qualitative studies was ‘socialisation of young women into submissiveness’. For the married young women two themes were identified a) submissive-accepting and b) submissive-victims. The married young women who belonged to the accepting group lived under compromised conditions but described themselves as satisfied with their situation. Women belonging to the victimized group experienced physical and verbal abuse for their inability to cope with the duties of a wife, caretaker of the home and bearer of children. Their situation was compounded by the power dynamics within the household (I). For the unmarried young women the main theme identified was security lies in obedience. The two sub-themes contributing to the main theme were socialisation into submissiveness and transition into adulthood in silence (II). The theme and the sub-themes illustrate the situation of young women in a poor setting in Pakistan. The main theme identified in the study with the parents was ‘Good parents’ strive to raise ‘innocent daughters’. The three sub-themes contributing to the main theme were: a daughter - a responsibility and a burden, social and sexual innocence and parents’ roles in the preparation for marriage. The theme and the sub-themes illustrate how the parents saw themselves as responsible for raising ‘innocent daughters’ and arranging good marriages (III). The quantitative study on the married young women showed that having a say in the selection of spouse at the time of marriage was significantly associated with agreeing with spouse over the number of children to have, intention to use contraceptives and the time between marriage and first contraceptive use. These relationships existed after controlling for education, socioeconomic status, mobility outside of house and decision making in the home (IV). Conclusions: In a culture of silence around sexuality, young women’s socialisation into submissiveness lays the foundation for the lack of control over their future reproductive health (I and II). The parents realised, though, that bringing up daughters for marriage requires not only obedience, but also building confidence and knowledge during their childhood (III). Women who had decision making freedom in their parental home carried this ability with them into marriage in their new home and were better able to negotiate about their fertility (IV). Knowledge about reproductive life could prepare young women better for the future life and give them more control of their fertility. Innovative interventions targeting women need to challenge current societal norms of womanhood to promote the upbringing of confident and knowledgeable young women

Development of Cost Effective and High Performance Composite for CO2 Capture in Ca-Cu Looping Process

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Combined sorbent and catalyst material for sorption enhanced reforming of methane under cyclic regeneration in presence of H2O and CO2

10 Figuras.- 2 Tablas.- 7 ExtrasAn investigation on an innovative calcium‑nickel Combined Sorbent and Catalyst Material (CSCM) for Sorption Enhanced Reforming (SER) of methane is presented in this paper. After hydrothermal synthesis, a nominal 30 wt% CaO-based sorbent supported on mayenite was physically mixed with a commercial reforming catalyst and granulated to obtain bifunctional particles of 200–300 μm. Materials were characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller surface analysis (BET) and Mercury- intrusion prosimetry (Hg-porosimetry). A novel thermo-gravimetric analysis (TGA) approach was employed for investigating SER activity, particularly the materials performance during multicycling methane reforming and sorbent carbonation followed by regeneration in oxidative atmosphere – either in the presence of steam or CO2 at high temperature. When regeneration is carried out in 100 vol% CO2 at 925 °C, an intermediate reduction step between cycles was crucial to maintain the catalytic activity of the CSCM for 100 consecutive sorption-regeneration cycles. In spite of a stable catalytic activity, the initial sorption capacity of the CSCM sorbent function (~16gCO2/100gCSCM) declined progressively with cyclic runs and stabilized at ~10gCO2/100gCSCM from cycle 90 onwards. This decline in capacity has been related to CaO depletion by solid phase reaction with the catalyst support.The presented work is funded within the ASCENT project as part of the European Union's Seventh Framework Program (FP7/2007-2013) under grant agreement n° 608512. Note: “The present publication reflects only the authors' views and the European Union is not liable for any use that may be made of the information contained therein”.Peer reviewe

Development of Cost Effective and High Performance Composite for CO2 Capture in Ca-Cu Looping Process

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Performance and operating limits of a sorbent-catalyst system for sorption-enhanced reforming (SER) in a fluidized bed reactor

10 Figures, 6 Tables.-- © 2019. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/The combined performance of a synthetic CaO-Ca12Al14O33 sorbent and an Ni-MgAl2O4 reforming catalyst was tested in a fluidized bed reactor under relevant operating conditions for the sorption-enhanced reforming (SER) process. The effect of CH4 space velocity (i.e. kgCH4/h·kgcat), steam-to-carbon (S/C) ratio and superficial gas velocity on product gas composition was assessed, as well as the effect of regeneration conditions on material performance. Moreover, a bi-functional material prepared by mechanical mixing of the separate materials was also tested in the reactor under consecutive SER/regeneration cycles. H2 contents as high as 96 vol% (N2 free, dry basis) were achieved under SER operation, using the separate materials working with an Ni content of 3.75 wt% in the solid bed at 650 °C with S/C ratios of 3 and 4. This solid system is able to process up to 0.63 kgCH4/h·kgcat at 0.1 m/s superficial gas velocity and with an S/C ratio of 4, although the CH4 input has to be reduced to 0.33 kgCH4/h·kgcat when working with a lower S/C ratio. Similar H2 contents to those found with the separate materials were obtained with the combined sorbent-catalyst material working with 0.33 kgCH4/h·kgcat at 0.1 m/s superficial gas velocity and S/C ratios of 3 and 4. The CO2 sorption capacity of the combined material produced the same as that of the separate sorbent particles (i.e. around 0.25 gCO2/g calcined sorbent), while remaining stable throughout the SER/regeneration cycles.This work was supported by the European Union (Grant agreement No. 608512) and the Regional Government of Aragon (DGA) under its research groups support programme.Peer reviewe

Implementation of the ANISA Study in Karachi, Pakistan: Challenges and Solutions

Background: Aetiology of Neonatal Infection in South Asia (ANISA) is a multicenter study in Bangladesh, India and Pakistan exploring the incidence and etiology of neonatal infections. A periurban site in Karachi was selected for its representativeness of the general population in neonatal health indicators. An established demographic surveillance system and other infrastructure needed for conducting the study already existed at this site. ANISA presents a unique challenge because of the need to capture every birth outcome in the community within a few hours of delivery to reliably estimate the incidence and etiology of early-onset sepsis in a setting where home births and deaths are common.CONTEXTUAL CHALLENGES: Major challenges at the Karachi site are related to early birth reporting and newborn assessment for births outside the catchment areas, parental refusal to participate, diverse ethnicity of the population, collection of biological specimens from healthy controls, political instability and crime, power outages and blood culture contamination. Some of the remedial actions taken include prolonging working hours; developing counseling skills of field workers; hiring staff with different linguistic abilities from within the study community; liaising with health facilities, key community informants, Lady Health Workers and traditional birth attendants; hiring community mobilizers; enhancing community sensitization; developing contingency plans for field work interruptions and procuring backup generators. The specimen contamination rate has decreased through training, supervision and video monitoring of blood collection procedures with individualized counseling of phlebotomists.CONCLUSION: ANISA offers lessons for successful implementation of complex study protocols in areas of high child mortality and challenging social environments