School of Sciences and Agriculturehttp://hdl.handle.net/10386/27932024-03-28T10:39:15Z2024-03-28T10:39:15ZIntegrated morphological and molecular characterization of the fish parasitic nematode Rhabdochona (Rhabdochona) gendrei Campana-Rouget, 1961 infecting Labeobarbus altianalis (Boulenger, 1900) in KenyaRindoria, Nehemiah M.Morara, George N.Smit, Willem J.Truter, MarlieseSmit, Nico J.Luus-Powell, Wilmien J.http://hdl.handle.net/10386/42612023-07-15T01:00:17Z2023-01-01T00:00:00ZIntegrated morphological and molecular characterization of the fish parasitic nematode Rhabdochona (Rhabdochona) gendrei Campana-Rouget, 1961 infecting Labeobarbus altianalis (Boulenger, 1900) in Kenya
Rindoria, Nehemiah M.; Morara, George N.; Smit, Willem J.; Truter, Marliese; Smit, Nico J.; Luus-Powell, Wilmien J.
During a parasitological survey carried out between May and August 2022 in the River Nyando, Lake Victoria
Basin, a single species of Rhabdochona Railliet, 1916 (Nematoda: Rhabdochonidae) was recorded from the intestine
of the Rippon barbel, Labeobarbus altianalis (Boulenger, 1900) (Cyprinidae). Based on light microscopy
(LM), scanning electron microscopy (SEM) and DNA analyses the parasite was identified as Rhabdochona
(Rhabdochona) gendrei Campana-Rouget, 1961. Light microscopy, SEM and DNA studies on this rhabdochonid
resulted in a detailed redescription of the adult male and female. The following additional taxonomic features are
described in the male: 14 anterior prostomal teeth; 12 pairs of preanal papillae: 11 subventral and one lateral; six
pairs of postanal papillae: five subventral and one lateral, with the latter pair at the level of first subventral pairs
when counted from the cloacal aperture. For the female: 14 anterior prostomal teeth and the size and absence of
superficial structures on fully mature (larvated) eggs dissected out of the nematode body. Specimens of R. gendrei
were genetically distinct in the 28S rRNA and cytochrome c oxidase subunit 1 (cox1) mitochondrial gene regions
from known species of Rhabdochona. This is the first study that provides genetic data for a species of Rhabdochona
from Africa, the first SEM of R. gendrei, and the first report of this parasite from Kenya. The molecular and SEM
data reported herein provide a useful point of reference for future studies on Rhadochona in Africa.
Journal article published in the International Journal for Parasitology: Parasites and Wildlife 21 (2023) 201-209
2023-01-01T00:00:00ZEvaluation of corrosion inhibition effect of glycerol stearate on aluminium metal by electrochemical techniquesPesha, ThaboMulaudzi, Vusimuzi L.Cele, Mduduzi L.Mothapo, Mmaphefo P.Ratshisindi, Fulufhelohttp://hdl.handle.net/10386/42602023-07-15T01:00:17Z2023-01-01T00:00:00ZEvaluation of corrosion inhibition effect of glycerol stearate on aluminium metal by electrochemical techniques
Pesha, Thabo; Mulaudzi, Vusimuzi L.; Cele, Mduduzi L.; Mothapo, Mmaphefo P.; Ratshisindi, Fulufhelo
The inhibitory effect of glycerol stearate (GS) on aluminium (Al) metal was examined
utilizing weight loss, potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy
(EIS) in hydrochloric acid (HCl) solution. Gravimetric analysis, PDP, and impedance
spectroscopy were used to calculate the rate of corrosion (EIS). Gravimetric measurement and electrochemical
methods both demonstrated that when the inhibitor concentration increased, the corrosion
rate decreased. PDP and EIS inhibition effectiveness was best at 50 10-5 mol. L-1 glycerol
stearate concentration,with 81.1% and 86.1%, respectively. The differences in corrosion potential
(Ecorr) values between the blank and inhibitor (GS) concentrations revealed that glycerol stearate
acted as a mixed type of corrosion inhibitor. The inhibitors’ adsorption on the aluminium surface
followed the Langmuir isotherm model. Fourier transform infrared spectroscopy (FTIR) indicated
the existence of an adsorption coating on the surface of the aluminium metal. SEM pictures of aluminium
demonstrated decreased inhomogeneities in the presence of glycerol stearate.
Journal article published in the Arabian Journal of Chemistry (2023) 16, 104798
2023-01-01T00:00:00ZHighly adsorptive removal of palladium and platinum ions from wastewater using novel ethylenediamine-glutaraldehyde-grafted metal organic frameworkMaponya, Thabiso C.Makgopa, KatlegoSomo, Thabang R.Tshwane, David M.Modibane, Kwena D.http://hdl.handle.net/10386/42592023-07-15T01:00:16Z2023-01-01T00:00:00ZHighly adsorptive removal of palladium and platinum ions from wastewater using novel ethylenediamine-glutaraldehyde-grafted metal organic framework
Maponya, Thabiso C.; Makgopa, Katlego; Somo, Thabang R.; Tshwane, David M.; Modibane, Kwena D.
Herein, a metal–organic framework (MIL-101(Cr)) was synthesized and functionalized with ethylenediamineglutaraldehyde
(ED-GA for removal of palladium (Pd2+) and platinum (Pt4+) from wastewater. The chemical
structure, surface properties, morphology, and adsorption energy of the prepared materials, MIL-101(Cr) and
MIL-101(Cr)/ED-GA were analyzed using several analytical techniques and density functional theory (DFT). The
prepared MIL-101(Cr)/ED-GA was efficient in removing Pd2+ and Pt4+ from aqueous solution with the percentage
removal reaching 95% for Pd2+ and 85% for Pt4+. Furthermore, the adsorption data demonstrated a
good fit to the Langmuir isotherm model and gave the maximum adsorption capacity values of 416.17 mg g 1 for
Pt4+ and and 322.6 mg g 1 for Pd2+ ions. Kinetics data obeyed a pseudo-second-order model and revealed the
rapid adsorption of Pd2+ and Pt4+ ions by MIL-101(Cr)/ED-GA which reached equilibrium within 10 and 40 min,
respectively. Lastly, DFT studies revealed that the adsorption of Pd2+ ions by the composite forms a more
thermodynamically stable compound than adsorption of Pt4+, suggesting that the material easily interacts with
Pd and high selectivity is thus expected. This was indeed confirmed by experimental selectivity test results.
Owing to their high affinity for PGMs, N atoms depicted large adsorption energy values compared to other
adsorption sites. The MIL-101(Cr)/ED-GA could act as an efficient and cost effective adsorbent for removal of
platinum group metals from wastewater.
Journal article published in the journal Environmental Nanotechnology, Monitoring & Management 20 (2023) 100805
2023-01-01T00:00:00ZDesign, synthesis and investigating the interaction of novel s-triazine collector with pyrite surface : a DFT-D3+U and experimental studiesMkhonto, Peace P.Zhang, XingrongLu, LiangXiong, WeiZhu, YanggeHan, LongNgoepe, Phuti E.http://hdl.handle.net/10386/42582023-07-15T01:00:13Z2023-01-01T00:00:00ZDesign, synthesis and investigating the interaction of novel s-triazine collector with pyrite surface : a DFT-D3+U and experimental studies
Mkhonto, Peace P.; Zhang, Xingrong; Lu, Liang; Xiong, Wei; Zhu, Yangge; Han, Long; Ngoepe, Phuti E.
In this study the green (environmentally friendly) novel di-sodium 2,6-dithio-4-butyl-amino-1,3,5-Triazine
(SDTBAT) collector also known as s-triazine molecule was designed and synthesised for use in sulphide minerals
separation. The SDTBAT adsorption was investigated on pyrite mineral surface using computational density
functional theory with dispersion correction and U-parameter (DFT-D3+U) as well as experimental methods. The
chemical adsorption behaviour of SDTBAT collector was compared with the sodium normal butyl xanthate
(SNBX) and sodium normal butyl dithiocarbamate (SNBDTC). Computationally, it was observed that the SDTBAT
adsorbed through the S and N atoms, while SNBX and SBDTC adsorbed through S atoms onto pyrite Fe atoms.
The adsorption energies followed the decreasing adsorption strength as: SDTBAT > SNBX > SNBDTC, which
suggested that the SDTBAT had strong exothermic adsorption than xanthate and DTC. The experimental microflotation
tests showed fast floating and higher recoveries of pyrite when using the SDTBAT collector compared to
xanthate and DTC. The XPS and FTIR analysis of pyrite-SDTBAT revealed that the SDTBAT adsorbed through S
and N atoms on Fe atoms. This clearly demonstrated that the SDTBAT was a potential collector to replace the
xanthate collector due to its high flotation power for separation of sulphide minerals.
Journal article published in the journal of Surfaces and Interfaces 38 (2023) 102820
2023-01-01T00:00:00Z