Studies of the superconducting properties of Sn1-xInxTe (x=0.38 to 0.45) using muon-spin spectroscopy

The superconducting properties of Sn1-xInxTe (x = 0.38 to 0.45) have been studied using magnetization and muon-spin rotation or relaxation (muSR) measurements. These measurements show that the superconducting critical temperature Tc of Sn1-xInxTe increases with increasing x, reaching a maximum at around 4.8 K for x = 0.45. Zero-field muSR results indicate that time-reversal symmetry is preserved in this material. Transverse-field muon-spin rotation has been used to study the temperature dependence of the magnetic penetration depth lambda(T) in the mixed state. For all the compositions studied, lambda(T) can be well described using a single-gap s-wave BCS model. The magnetic penetration depth at zero temperature lambda(0) ranges from 500 to 580 nm. Both the superconducting gap Delta(0) at 0 K and the gap ratio Delta(0)/kBTc indicate that Sn1-xInxTe (x = 0.38 to 0.45) should be considered as a superconductor with intermediate to strong coupling.Comment: 7 pages, 6 figures, 3 table

Observation of surface states on heavily indium doped SnTe(111), a superconducting topological crystalline insulator

The topological crystalline insulator tin telluride is known to host superconductivity when doped with indium (Sn$_{1-x}$In$_{x}$Te), and for low indium contents ($x=0.04$) it is known that the topological surface states are preserved. Here we present the growth, characterization and angle resolved photoemission spectroscopy analysis of samples with much heavier In doping (up to $x\approx0.4$), a regime where the superconducting temperature is increased nearly fourfold. We demonstrate that despite strong p-type doping, Dirac-like surface states persist

Nanomaterials of the topological crystalline insulators, Pb1–xSnxTe and Pb1–xSnxSe

Topological insulators (TIs) and topological crystal insulators (TCIs) exhibit exotic surface properties. We present optimised growth procedures to obtain high quality bulk crystals of the TCIs Pb1-xSnxTe and Pb1-xSnxSe, and nanowires from the bulk crystals using the vapour-liquid-solid (VLS) technique. Nanowires of Pb1-xSnxTe have been produced with a Sn composition of x = 0.25, at which a transition from trivial to non-trivial insulator is reported. The results obtained on the growth of nanomaterials of Pb1-xSnxSe are also described. Detailed characterisation of the bulk crystals and the nanomaterials through x-ray diffraction, microscopy techniques and EDX analysis are presente

Integrating improved goat breeds with new varieties of sweet potatoes and cassava in the agro-pastoral systems of Tanzania: A gendered analysis

This paper focuses on analysing gender issues in livestock and root crop production. Qualitative data for the study was collected through gender disaggregated group discussions (GDs) in two districts, Mvomero and Kongwa in Tanzania. Data were collected from 4 communities representing the four villages—Wami Luhindo and Kunke in Mvomero, and Masinyeti and Ihanda in Kongwa respectively. A total of 12 GDs were conducted involving 224 men and women who participated in the GDs. The qualitative data were analysed descriptively and by using measures such as percentages, tables, pie, bar charts and Venn diagrams. The study found that men owned all the goats and made all goat related decisions unilaterally. Women were by far less likely than men to own not only goats, but also livestock in general. On management of goats, an important set of differences in activities is associated with gender as well as with age. Changing livelihood opportunities such as rural–urban migration were identified as a factor that influenced gender and goat management and this increases workload for women. On decision-making over goats, women have limited control over decisions on sale and use of incomes generated from sale of goats. Ownership of crops between men and women is quite distinct, and depends on the market prices of crops and yield of the crop they grow for cash. Men own cash crops or crops for cash whereas women own subsistence or food crops for home consumption. Wealth status had a direct relation with individual decision-making on crops, rich men and women decided on what crops to cultivate, whereas non-rich farmers worked on wealthy farmers’ farms as casual labourers. Perceptions of women and men on the potential benefits of integrating root crops and goat varied. Men perceived value addition resulting from owning dairy goats and the attendant increase in income for them whereas women perceived change in status quo and increase workload resulting from stall goat management activities. Some participants explained that the anticipated increase in men’s real income could come about either through men accessing women’s income, or more commonly, women using their earnings to substitute men’s expenditure on household needs and children’s education. The study concluded that there are gender differences on perceived potential of integrating root crops and dairy goat production, as prevailing tradition may limit women’s participation. The beneficiaries expressed the timeliness of CGP project and exhibited willingness to partake in the project and ensure equitable benefits for participants if participatory gender training and awareness is ensured at both the household and community level. The study recommended that investing in rigorous gender trainings for both women and men, to initially sensitize them on the importance of including both women and men in development projects and sustain their continued understanding of the importance of gender inclusive activities

Cassava: adding value for Africa - Strategic market initiatives that support wealth creation for women along the Cassava Value Chains in Southwest, Nigeria.

Empowering and creating wealth for cassava producing and processing smallholder farmers (of which women constitute the majority) through value addition and competitive market led opportunities for inclusive growth in agriculture is very important to counter poverty and ensure food security. This study attempts to examine the extent to which Cassava: Adding Value for Africa (C:AVA) project in Nigeria has created market led opportunities for smallholder farmers of cassava roots in Southwest Nigeria from 2008 to 2010. Data were collected through interview schedule administered on 237 randomly selected farmers who are participants in C:AVA project registered with the Agricultural Development Project (ADP) in Ogun, Ondo States and Justice, Development and Peace Movement (JDPM). Catholic Diocese of Abeokuta from Ogun State and Ondo State respectively. Data were analyzed descriptively by using measures such as frequency distribution, table, percentages and Chi-Square. The study revealed that 60% of the respondents were men and 40% were women. Men were more educated that women with 28.6% of women farmers having no formal education when compared with 10.3% of men. The difference in income between the third and fourth quartile was very high compared with other quartiles and the mean income earned by male farmers was more than twice the mean income earned by female farmers. With regards to level of production there was an increase in the yield of cassava roots on the farms surveyed from the average national range of 10-12 tonnes/ha in 2008 to an average range of 20-25 tonnes/ha in 2010. These improved varieties resulted in an average yield advantage of about 65% over local varieties. Owing to the observable increase in yield, farmers in the study area increased the hectares under cassava from an average of 0.5 - 1.5 ha in 2008 to an average of 10.0-20.0 ha in 2010. The average annual income of women farmers increased from $1000 in 2008 to an additional average income of$1700 in 2010. Chi-square analysis revealed significant associations (p<0.05) between yield of improved varieties (X2=29.187), gender (X2=50.632), value addition (X2=32.547), improved technologies (X2=29.507); Types of market (X2=14.743), group membership (X2=10.973), capacity building (X2=68.490) with income. The study concluded that C:AVA has provided systematic development of specialization in which women cassava roots producers/ processors produce specifically for multiple markets to ensure wealth and household food security for women and their households

Three dimensional simulation to observe the effects of the static magnetic field on the growth of Si0.25Ge0.75 in a vertical Bridgman setting

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.A numerical modeling and simulation of single bulk crystals of Si0.25Ge0.75 growth with Si rich is conducted to investigate the effect of static magnetic field on the heat and mass transfer in the solvent region in a vertical Bridgman furnace. The curvature and shape of the silicon concentration in the process of crystallization near the growth interface are also examined. Different magnetic field intensities were applied. The meridianal flow as well as the azimuthal flow in the solvent region under the applied polynomial temperature along the vertical dimension of the model were investigated and it was found that the axial magnetic field does not have effective influence on the buoyancy induced convection in the solvent region.dc201

Endülüs’ün Büyük Filozofu İbn Bâcce

İbn Bâcce İslam felsefesinin ve Meşşâî geleneğin öne çıkan filozoflarındandır. Endülüs’ün önemli filozoflarından biri olan İbn Bâcce’nin düşünceleri İslam Felsefesinin yanında Batı aydınlanmasına da tesir etmiştir. Yaptığı Aristo yorumları nedeniyle Latincede Avenpace ve Avempace olarak bilinir. Tıp, felsefe, edebiyat, astronomi, matematik, tabiat ilimleri ve musiki alanında ciddi bir eğitimi olan İbn Bâcce, aynı zamanda hafız olup, İslami disiplinlerde uzmandır. Meşşâî geleneğe mensup olmakla birlikte kendine özgün fikirleri de olan İbn Bâcce, bir dönem Gırnata ve doğum yeri olan Sarakusta’da vezirlik yapmıştır. Talebesi İbn Tufeyl’in (ö. 581/1185) belirttiği üzere vezirlik ve saray tabipliği görevinden dolayı felsefi fikirlerini yazmakla yeterince ilgilenememiştir. Murabıtlar devletinde yöneticilik yaptığı sırada devlet ve halk arasındaki ilişkileri, gelenek ve görenekleri, diğer devletlerle olan irtibatı, üretim ve tüketim ilişkilerini gözlemlemiştir. Ayrıca hekim olduğu için insan ve yetilerini ayrıntılı analiz etmiştir. Görüşlerinden dolayı, kendisini dinsizlikle itham edenler arasında dönemin âlimlerinden Feth b. Hakan el-Kaysi (ö. 529/1135), meşhur tabip Ebü’l-Alâ İbn Zühr (ö. 470/1078), İbnü’s-Sîd el-Batalyevsî (ö. 521/1127) de vardı. Bundan dolayı İbn Bâcce’nin vefat nedeninin zehirlenme olduğu iddia edilmiştir