Synthesis and Characterization of ZnO Nanopowders and ZnO-CNT Nanocomposites Prepared by Chemical Precipitation Route

The aims of this work are synthesis of ZnO nanopowders and producing nanocomposites by mixing with carbon nanotubes. ZnO nanopowders have been synthesized by chemical precipitation route. Dierent amount of collected nanosized Zn-based precipitates and chemically oxidized carbon nanotubes powder have been mix together and annealed at 400 • C. Characterization of produced nanopowders and nanocomposites have been carried out by X-ray diractometer and scanning electron microscope

Prevalence of Urinary Incontinence and Probable Risk Factors in a Sample of Kurdish Women

Objectives: The most common manifestation of pelvic floor dysfunction is urinary incontinence (UI) which affects 15–50% of adult women depending on the age and risk factors of the population studied. The aim of this study was to determine the probable risk factors associated with UI; the characteristics of women with UI; describe the types of UI, and determine its prevalence. Methods: A cross-sectional study was conducted between February and August 2011, in the Maternity Teaching Hospital of the Erbil Governorate, Kurdistan Region, northern Iraq. It included 1,107 women who were accompanying patients admitted to the hospital. A questionnaire designed by the researchers was used for data collection. A chi-square test was used to test the significance of the association between UI and different risk factors. Binary logistic regression was used, considering UI as the dependent variable. Results: The overall prevalence of UI was 51.7%. The prevalence of stress, urgency, and mixed UI was 5.4%, 13.3% and 33%, respectively. There was a significant positive association between UI and menopause, multiparity, diabetes mellitus (DM), chronic cough, constipation, and a history of gynaecological surgery, while a significant negative association was detected between UI and a history of delivery by both vaginal delivery and Caesarean section. Conclusion: A high prevalence of UI was detected in the studied sample, and the most probable risk factors were multiparity, menopausal status, constipation, chronic cough, and DM

The effect of different feeding frequency on growth indices, survival and body composition of Oriental River Prawn Macrobrachium nipponense (De Haan, 1849)

This research was carried out in order to identify the effects of different feeding frequency on growth indices, feed conversion ratio, survival and body composition of oriental river prawn (Macrobrachium nipponense) during 56 days. 180 oriental river prawns, with mean (±SE) weight 1.40±0.11g were counted and distributed randomly in twelve 70-liter glass tanks with 60 l water in 4 treatments each with 3 replicates cultured in same conditions (dietary feeding, dissolved oxygen, photoperiod, density, 2% feeding rate). Feeding were done 3, 4, 5 and 6 times/day with a constant commercial diet (50% protein, 13% fat, 12% ash, moisture 10-12 %). At the end of experiment, growth indices, feed conversion ratio, body composition ratio were measured for each treatment. Mean final weight, weight gain and specific growth rate in the treatment feeding 5 times/day was higher than the other treatments (p0.05).The lowest feed conversion ratio was obtained in 5 times/day feeding and feeding 4 and 5 times/day treatments (68.80±1.8 and 77.60±2.5 %, respectively) had the highest survival rate. The highest body protein content (12.86±0.07 %) and fat content (3.46±0.02%) were obtained from the 5 times/day feeding. Results indicate that 5 times/day feeding has a significant difference in the increase of growth indices, survival rate, reduced feed conversion ratio, increased carcass protein and fat content, with other treatments (p<0.05)

Palladium nanoparticles supported on fluorine-doped tin oxide as an efficient heterogeneous catalyst for Suzuki coupling and 4-nitrophenol reduction

Immobilization of palladium nanoparticles onto the fluorine-doped tin oxide (FTO) as support Pd/FTO, resulted in a highly active heterogeneous catalyst for Suzuki-Miyaura cross-coupling reactions and 4-nitrophenol reduction. The Pd/FTO catalyst has been synthesized by immobilization of palladium nanoparticles onto FTO via a simple impregnation method. ICP-MS analysis confirmed that there is 0.11 mmol/g of palladium was loaded successfully on FTO support. The crystallinity, morphologies, compositions and surface properties of Pd/FTO were fully characterized by various techniques. It was further examined for its catalytic activity and robustness in Suzuki coupling reaction with different aryl halides and solvents. The yields obtained from Suzuki coupling reactions were basically over 80%. The prepared catalyst was also tested on mild reaction such as reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). Pd/FTO catalyst exhibited high catalytic activity towards 4-NP reduction with a rate constant of 1.776 min(-1) and turnover frequency (TOF) value of 29.1 hr(-1). The findings revealed that Pd/FTO also maintained its high stability for five consecutive runs in Suzuki reactions and 4-NP reductions. The catalyst showed excellent catalytic activities by using a small amount of Pd/FTO for the Suzuki coupling reaction and 4-NP reduction

The Superior Surface Discharge Capacity of Core-Shell Tinoxide/Multi Walled Carbon Nanotube Nanocomposite Anodes for Li-Ion Batteries

In this study, tin/tinoxide/multiwalled carbon nanotube (Sn/$SnO_2$/MWCNT) nanocomposites were produced as anode materials for Li-ion batteries by a two-step process. Metallic tin was evaporated onto free-standing MWCNT buckypapers having controlled porosity and subsequently rf plasma oxidized in Ar:$O_2$ (1:1) gas mixture. Besides, Sn/$SnO_2$ nanocomposites were produced in the same conditions onto stainless steel substrates to make a comparison. X-ray diffraction and scanning electron microscopy were used to determine the structure and morphology of the obtained nanocomposites. The discharge/charge tests, cyclic voltammetry and electrochemical impedance spectroscopy were carried out to characterize the electrochemical properties of these composites. Promising results were obtained in the tin based MWCNT nanocomposites for next-generation micro battery applications because of the high active surface area of the $SnO_2$/MWCNT core-shell structures

Production of Sn/SnO2/MWCNT composites by plasma oxidation after thermal evaporation from pure Sn targets onto buckypapers

PMID = 2344795

Graphene supported heterogeneous catalysts for Li-O-2 batteries

In this study production and characterization of free-standing and flexible (i) graphene, (ii) alpha-MnO2/graphene, (iii) Pt/graphene (iv) alpha-MnO2/Pt/graphene composite cathodes for Li-air batteries were reported. Graphene supported heterogeneous catalysts were produced by a facile method. In order to prevent aggregation of graphene sheets and increase not only interlayer distance but also surface area, a trace amount multi-wall carbon nano tube (MWCNT) was introduced to the composite structure. The obtained composite catalysts were characterized by SEM, X-ray diffraction, N-2 adsorption-desorption analyze and Raman spectroscopy. The electrochemical characterization tests including galvanostatic charge/discharge and electrochemical impedance spectroscopy (EIS) measurement of catalyst were carried out by using an ECC-Air test cell. These highly active graphene supported heterogeneous composite catalysts provide competitive properties relative to other catalyst materials for Li-air batteries. (C) 2016 Elsevier B.V. All rights reserved

Sn/SnO2/Mwcnt composite anode and electrochemical impedance spectroscopy studies for Li-ion batteries

Tin/tinoxide/multi-walled carbon nanotube (Sn/SnO2/MWCNT) core-shell structure nanocomposite anode is produced by thermal evaporation and subsequent plasma oxidation with using MWCNT buckypaper. Metallic tin is evaporated onto free-standing and flexible MWCNT buckypaper having controlled porosity and subsequent RF plasma oxidized in Ar:O-2(1:1) gas mixture. X-ray diffraction and scanning electron microscopy are used to determine the structure and morphology of the obtained nanocomposite. The electrochemical characteristics of the nanocomposite anode are examined by using electrochemical impedance spectroscopy and galvanostatic charge-discharge experiments. Family of Nyquist plots during first discharge process are obtained and studied at different voltage values

Synthesis of ZnO, SnO2 nanoparticles and preparation of ZnO-SnO2 nanocomposites

PMID = 2344797