Adsorption studies on the treatment of battery wastewater by purified carbon nanotubes (P-CNTs) and polyethylene glycol carbon nanotubes (PEG-CNTs).

Fe-Ni/kaolin catalyst was used for the production of carbon nanotubes (CNTs) via catalytic chemical vapour deposition followed by acid purification treatment and functionalization with polyethylene glycol to give purified carbon nanotubes (P-CNTs) and polyethylene glycol carbon nanotubes (PEG-CNTs), respectively. The as-synthesized CNTs, P-CNTs and PEG-CNTs were characterized by high-resolution transmission electron microscopy (HRTEM), high-resolution scanning electron microscopy (HRSEM), Fourier transform infrared and Brunauer Emmett Teller (BET). The adsorption behaviour P-CNTs and PEG-CNTs to remove specifically Cr and Zn from battery wastewater were examined by the batch adsorption process as a function of different contact time, adsorbent dosage and temperature. The HRSEM/HRTEM/BET analysis confirmed that both nano-adsorbents were tube-like in nature, high porosity and crystalline, with PEG-CNTs possessing high surface area (970.81 m2/g) than P-CNTs (781.88 m2/g). The optimum contact time and adsorbent dosage to remove Cr and Zn by P-CNTs and PEG-CNTs were 90 and 50 min and 0.3 g, respectively. Under the applied conditions, PEG-CNTs exhibited high adsorption capacity than P-CNTs for the selected heavy metals. The adsorption equilibrium data were better fitted to the Freundlich model while the kinetic data conformed to the pseudo-second-order model. Thermodynamic studies demonstrated the feasibility and endothermic nature of the system. This study demonstrated that both nano-adsorbents purify battery wastewater and with better performance by PEG-CNTs.

Photocatalytic degradation of local dyeing wastewater by iodine-phosphorus co-doped tungsten trioxide nanocomposites under natural sunlight irradiation.

In the present work, one-step green synthesis of WO3 based on the interaction of ammonium paratungstate and Spondias mombin leaves extract is reported. Different concentrations of iodine and phosphorus in the range of (2%, 5% and 10%) were firstly incorporated into the prepared WO3 nanoparticles to obtain Iodine doped and Phosphorus doped WO3 nanoparticles respectively. Subsequently, iodine and phosphorus co-doped WO3 nanocomposites was prepared using a wet impregnation method followed by calcination at high temperature. The nanomaterials were characterized by HRSEM, HRTEM, BET, UV-Visible, EDS, XRD and XPS. The photo-oxidation of dyeing wastewater by the synthesized WO3 nanomaterials were tested and assessed using Total organic carbon (TOC) and Chemical oxygen demand (COD) as indicator parameters. XRD and HRSEM analysis demonstrated the formation of only monoclinic phase of WO3 irrespective of the dopants. The UV-Visible diffuse reflectance spectroscopy showed the band gap energy of 2.61 eV for undoped WO3 and 2.02 eV for I-P co-doped WO3 nanocomposites. The surface area of I-P co-doped WO3 (416.18 m2/g) was higher than the undoped WO3 (352.49 m2/g). The XPS demonstrated interstitial and substitution of oxygen (O2-) vacancies in WO3 by I- and P3+ and formed I-P-WO(3-x). The I-P co-doped WO3 exhibited higher catalytic activities (93.4% TOC, 95.1% COD) than the undoped (54.9% TOC, 79.2% COD) due to the synergistic effects between the two dopants. The experimental data better fitted to pseudo-second order than first order and pseudo-first order model. This study demonstrated the enhanced photocatalytic performance of I-P co-doped WO3 nanocomposites under sunlight.

Swollen Forearm in an 11 year Old Nigerian Boy

The diagnostic challenges in an 11 year old boy with a swollen forearm in a resource limited country; Nigeria; is discussed; with a brief review of literature of the causes of forearm swelling in a child and vascular malformations. This case is presented because of the rarity of arteriovenous malformation and the difficulty in making a diagnosis due to its low level of suspicion as a differential diagnosis. In this country where there is paucity of vascular surgeons; the challenges of management of arteriovenous malformations and the various imaging modalities are discussed

Significance of yeasts in the fermentation of maize for ogi production.

Saccharomyces cerevisiae, Candida krusei, C. tropicalis, Geotrichum candidum, G. fermentans and Rhodotorula graminis were isolated during the fermentation of maize for ogi production. All the isolates except Geotrichum fermentans and Rhodotorula graminis were able to degrade phytate. All the yeasts strains exhibited lipase and esterase activities. Only S. cerevisiae (2.60%) and C. krusei (7.41%) exhibited amylase activities. Candida sp. produced wider zone of inhibition than the other yeasts strains tested during lipase activity while S. cerevisiae strains produced significantly wider zone of clearing as compared to the other yeasts for esterase activities. The study of inter-relationships between Lactobacillus plantarum and yeasts (C. krusei and S. cerevisiae) showed that the growth of the yeast strains were enhanced during fermentation by the presence of the lactic acid bacteria, but the growth of the L. plantarum strain was significantly enhanced especially by the C. krusei.

Diagnostic methods for typhoid fever in Nigeria.

In this study, 65 patients are screened for Salmonella typhi by conventional culture and the Widal test. In addition, the patients undergo full blood count are screened for malaria parasites. Of the 65 patients, 50 report febrile conditions, while the remaining 15 are used as a control population. In the febrile group, 13 (26%) were positive for S. typhi, while in the control group only one (7%) was positive for S. typhi. Overall, 36 (64.3%) patients had malaria parasites. Patients with a higher O antibody titre (> or = 1 in 80) by Widal test were found to have consumed both tap water and pure water. More females (10/14; mean age: 33) had typhoid fever as a result of S. typhi infection, the majority of which were isolated from stool samples (57%). Nine of the isolates were also positive for malaria parasites, seven of which were in the trophozoite stage. Plasmodium falciparum was the predominant parasite (78%), the remainder being P. malariae. The majority of patients (12/14) with typhoid fever had normal PCV values. In conclusion, it is recommended that tests for the diagnosis of typhoid fever in Nigeria should include malaria parasites, S. typhi culture from faecal samples, and the Widal test.

Use of starter cultures containingStreptococcus diacetilactis, Lactobacillus brevis andSaccharomyces cerevisiae for fermenting milk for production of Nigeriannono.

Starter cultures consisting ofStreptococcus diacetilactis, Strept. cremoris, Lactobacillus brevis andSaccharomyces cerevisiae were tested singly and in mixtures for ability to ferment milk to producenono with organoleptically acceptable qualities. Only mixed cultures containing eitherStrept. diacetilactis orStrept. cremoris andL. brevis were suitable. Presence of yeast adversely affected either acid formation or diacetyl production.Nono containingStrept. diacetilactis was acceptable, even in the presence ofSacch. cerevisiae, because of the high diacetyl production. A mixed starter containing two of these organisms,Strept. diacetilactis orStrept. cremoris andL. brevis, is recommended fornono production.Sacch. cerevisiae is not essential.

Foreign bodies in the tracheobronchial tree: management and complications.

Accidental inhalation of a foreign body into the air passages is not an uncommon occurrence in any age group, but it is more frequent in the younger age group. Thirty-seven of the 47 patients (78.7 percent) in the present study were under 16 years of age. Most of the foreign bodies were found in the right bronchus. In this series, 73.9 percent of the interbronchial foreign bodies were recovered by bronchoscopy, while 6.5 and 19.6 percent were recovered during emergency tracheotomy and bronchotomy, respectively. The mortality in this series was 6.4 percent.