for Journals by Title or ISSN
for Articles by Keywords
help

Publisher: Sabinet Online Ltd   (Total: 184 journals)

 A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  

              [Sort by number of followers]   [Restore default list]

Showing 1 - 184 of 184 Journals sorted alphabetically
ACCORD Occasional Paper     Open Access   (Followers: 4)
Acta Academica     Full-text available via subscription   (Followers: 6, SJR: 0.124, CiteScore: 0)
Acta Classica : Proceedings of the Classical Association of South Africa     Full-text available via subscription   (Followers: 7, SJR: 0.133, CiteScore: 0)
Acta Criminologica     Full-text available via subscription   (Followers: 1)
Acta Germanica : German Studies in Africa     Full-text available via subscription   (Followers: 1)
Acta Juridica     Full-text available via subscription   (Followers: 7)
Acta Patristica et Byzantina     Full-text available via subscription   (Followers: 8)
AFFRIKA J. of Politics, Economics and Society     Full-text available via subscription   (Followers: 4)
Africa Conflict Monitor     Full-text available via subscription   (Followers: 5)
Africa Insight     Full-text available via subscription   (Followers: 16)
Africa Institute Occasional Paper     Full-text available via subscription   (Followers: 3)
AfricaGrowth Agenda     Full-text available via subscription   (Followers: 1)
African Entomology     Full-text available via subscription   (Followers: 9, SJR: 0.374, CiteScore: 1)
African Finance J.     Full-text available via subscription   (Followers: 15, SJR: 0.184, CiteScore: 0)
African J. for Physical, Health Education, Recreation and Dance     Full-text available via subscription   (Followers: 7)
African J. of Business and Economic Research     Full-text available via subscription   (Followers: 3)
African J. of Democracy and Governance     Full-text available via subscription   (Followers: 5)
African J. of Herpetology     Full-text available via subscription   (Followers: 6, SJR: 0.468, CiteScore: 1)
African J. of Research in Mathematics, Science and Technology Education     Full-text available via subscription   (Followers: 8, SJR: 0.178, CiteScore: 0)
African J. of Rhetoric     Full-text available via subscription   (Followers: 5)
African J. of Wildlife Research     Full-text available via subscription   (Followers: 5, SJR: 0.411, CiteScore: 1)
African Plant Protection     Open Access   (Followers: 2)
African Renaissance     Full-text available via subscription   (Followers: 3)
African Safety Promotion     Full-text available via subscription   (Followers: 4)
African Yearbook of Rhetoric     Full-text available via subscription   (Followers: 4)
Africanus     Full-text available via subscription   (Followers: 3)
Agriprobe     Open Access  
Akroterion     Full-text available via subscription   (Followers: 5)
Annals of the Ditsong National Museum of Natural History     Full-text available via subscription   (Followers: 3)
Ars Nova     Full-text available via subscription   (Followers: 2)
Article 40     Open Access   (Followers: 2)
BER : Architects and Quantity Surveyors' Survey     Full-text available via subscription   (Followers: 6)
BER : Building and Construction : Full Survey     Full-text available via subscription   (Followers: 10)
BER : Building Contractors' Survey     Full-text available via subscription   (Followers: 2)
BER : Building Sub-Contractors' Survey     Full-text available via subscription   (Followers: 2)
BER : Capital Goods Industries Survey     Full-text available via subscription  
BER : Consumer Confidence Survey     Full-text available via subscription   (Followers: 3)
BER : Consumer Goods Industries Survey     Full-text available via subscription  
BER : Economic Prospects : An Executive Summary     Full-text available via subscription  
BER : Economic Prospects : Full Survey     Full-text available via subscription   (Followers: 1)
BER : Intermediate Goods Industries Survey     Full-text available via subscription   (Followers: 1)
BER : Manufacturing Survey : Full Survey     Full-text available via subscription   (Followers: 1)
BER : Motor Trade Survey     Full-text available via subscription  
BER : Retail Sector Survey     Full-text available via subscription   (Followers: 1)
BER : Retail Survey : Full Survey     Full-text available via subscription   (Followers: 1)
BER : Survey of Business Conditions in Building and Construction : An Executive Summary     Full-text available via subscription   (Followers: 3)
BER : Survey of Business Conditions in Manufacturing : An Executive Summary     Full-text available via subscription   (Followers: 3)
BER : Survey of Business Conditions in Retail : An Executive Summary     Full-text available via subscription   (Followers: 3)
BER : Trends : Full Survey     Full-text available via subscription   (Followers: 1)
BER : Wholesale Sector Survey     Full-text available via subscription  
Building Women     Full-text available via subscription  
Bulletin of Statistics     Full-text available via subscription   (Followers: 3)
Business Tax and Company Law Quarterly     Full-text available via subscription   (Followers: 8)
Cabo     Full-text available via subscription  
Cardiovascular J. of Africa     Full-text available via subscription   (Followers: 4, SJR: 0.494, CiteScore: 1)
Cardiovascular J. of South Africa     Full-text available via subscription   (Followers: 1)
Child Abuse Research in South Africa     Full-text available via subscription   (Followers: 1)
Civil Engineering = Siviele Ingenieurswese     Full-text available via subscription   (Followers: 4, SJR: 0.101, CiteScore: 0)
Clean Air J.     Full-text available via subscription   (Followers: 1)
Clean Air J. = Tydskrif vir Skoon Lug     Full-text available via subscription  
Climate Summary of South Africa     Full-text available via subscription   (Followers: 1)
Commonwealth Youth and Development     Full-text available via subscription   (Followers: 4)
Communicare : J. for Communication Sciences in Southern Africa     Full-text available via subscription   (Followers: 4)
Comparative and Intl. Law J. of Southern Africa     Full-text available via subscription   (Followers: 2)
Conflict Trends     Full-text available via subscription   (Followers: 13)
Conspectus : The J. of the South African Theological Seminary     Open Access   (Followers: 3)
Current Allergy & Clinical Immunology     Open Access   (Followers: 8, SJR: 0.145, CiteScore: 0)
De Arte     Full-text available via subscription   (Followers: 4)
De Rebus     Full-text available via subscription   (Followers: 1)
Die Kerkblad     Full-text available via subscription  
Educare     Full-text available via subscription   (Followers: 1)
Emergency Services SA     Full-text available via subscription   (Followers: 2)
English in Africa     Full-text available via subscription   (Followers: 4)
Ergonomics SA : J. of the Ergonomics Society of South Africa     Full-text available via subscription   (Followers: 3)
ESR Review : Economic and Social Rights in South Africa     Open Access   (Followers: 3)
Evidence Based Summaries in Dentistry     Full-text available via subscription   (Followers: 1)
FarmBiz     Full-text available via subscription  
Farmer’s Weekly     Full-text available via subscription  
Farmlink Africa     Full-text available via subscription  
Food Manufacturing Africa     Full-text available via subscription  
French Studies in Southern Africa     Full-text available via subscription   (Followers: 1)
Fundamina : A J. of Legal History     Open Access   (Followers: 7)
Gender and Behaviour     Full-text available via subscription   (Followers: 9)
Gender Questions     Full-text available via subscription   (Followers: 2)
Ghanaian J. of Economics     Full-text available via subscription  
HR Future     Full-text available via subscription   (Followers: 2)
IFE Psychologia : An Intl. J.     Full-text available via subscription   (Followers: 1)
Image & Text : a J. for Design     Full-text available via subscription   (Followers: 17)
IMFO : Official J. of the Institute of Municipal Finance Officers     Full-text available via subscription   (Followers: 1)
IMIESA     Full-text available via subscription  
Indilinga African J. of Indigenous Knowledge Systems     Full-text available via subscription   (Followers: 4)
Inside Mining     Full-text available via subscription  
Institute for Security Studies Papers     Full-text available via subscription   (Followers: 2)
Interim : Interdisciplinary J.     Open Access   (Followers: 4)
Intl. J. for Religious Freedom     Full-text available via subscription  
J. for Christian Scholarship = Tydskrif vir Christelike Wetenskap     Full-text available via subscription   (Followers: 4)
J. for Contemporary History     Full-text available via subscription   (Followers: 16)
J. for Islamic Studies     Full-text available via subscription   (Followers: 16)
J. for Juridical Science     Full-text available via subscription  
J. for Language Teaching = Tydskrif vir Taalonderrig     Full-text available via subscription   (Followers: 1)
J. for New Generation Sciences     Open Access   (Followers: 4)
J. for Semitics     Full-text available via subscription   (Followers: 8)
J. of African Elections     Full-text available via subscription  
J. of African Foreign Affairs     Full-text available via subscription   (Followers: 2)
J. of African Union Studies     Full-text available via subscription  
J. of Contemporary Management     Full-text available via subscription  
J. of Gender, Information and Development in Africa     Full-text available via subscription   (Followers: 4)
J. of Minimum Intervention in Dentistry     Full-text available via subscription  
J. of Public Administration     Full-text available via subscription   (Followers: 26)
J. of Somali Studies     Full-text available via subscription  
J. of Strategic Studies : A J. of the Southern Bureau of Strategic Studies Trust     Full-text available via subscription   (Followers: 1)
Kleio     Full-text available via subscription   (Followers: 1)
Learning and Teaching Mathematics     Full-text available via subscription   (Followers: 4)
Litnet Akademies : 'n Joernaal vir die Geesteswetenskappe, Natuurwetenskappe, Regte en Godsdienswetenskappe     Open Access  
Management Dynamics : J. of the Southern African Institute for Management Scientists     Full-text available via subscription   (Followers: 1)
Medical Technology SA     Full-text available via subscription  
Meditari : Research J. of the School of Accounting Sciences     Full-text available via subscription   (Followers: 1)
MNASSA : Monthly Notes of the Astronomical Society of South Africa     Full-text available via subscription  
Monographs of the Transvaal Museum     Full-text available via subscription  
Musicus     Full-text available via subscription  
Neotestamentica     Full-text available via subscription   (Followers: 9, SJR: 0.119, CiteScore: 0)
New Coin Poetry     Full-text available via subscription   (Followers: 2, SJR: 0.103, CiteScore: 0)
New Voices in Psychology     Full-text available via subscription   (Followers: 1)
Obiter     Full-text available via subscription   (Followers: 1)
Obstetrics and Gynaecology Forum     Full-text available via subscription   (Followers: 1, SJR: 0.111, CiteScore: 0)
Occupational Health Southern Africa     Full-text available via subscription   (Followers: 1)
Old Testament Essays     Full-text available via subscription   (Followers: 16)
Personal Finance Newsletter     Full-text available via subscription   (Followers: 1)
Perspectives in Education     Full-text available via subscription   (Followers: 1, SJR: 0.137, CiteScore: 0)
Politeia     Full-text available via subscription  
Professional Accountant     Full-text available via subscription   (Followers: 1)
Professional Nursing Today     Full-text available via subscription   (Followers: 5)
Progressio     Full-text available via subscription   (Followers: 2)
Psycho-analytic Psychotherapy in South Africa     Full-text available via subscription   (Followers: 2)
Quest     Open Access  
ReSource     Full-text available via subscription  
Retail and Marketing Review     Full-text available via subscription   (Followers: 1)
Rostrum : Newsletter of the Entomological Society of Southern Africa     Open Access   (Followers: 1)
SA Irrigation = SA Besproeiing     Full-text available via subscription   (Followers: 1, SJR: 0.283, CiteScore: 1)
SA Mercantile Law J. = SA Tydskrif vir Handelsreg     Full-text available via subscription   (Followers: 1)
SABI Magazine - Tydskrif     Full-text available via subscription  
Scriptura : Intl. J. of Bible, Religion and Theology in Southern Africa     Open Access   (Followers: 8)
Scrutiny2     Full-text available via subscription  
Servamus Community-based Safety and Security Magazine     Full-text available via subscription  
Shakespeare in Southern Africa     Full-text available via subscription   (Followers: 4)
South African Actuarial J.     Full-text available via subscription  
South African Computer J.     Full-text available via subscription   (SJR: 0.264, CiteScore: 1)
South African Food Review     Full-text available via subscription  
South African Gastroenterology Review     Full-text available via subscription   (SJR: 0.104, CiteScore: 0)
South African Health Review     Open Access   (Followers: 2)
South African J. for Research in Sport, Physical Education and Recreation     Full-text available via subscription   (Followers: 6, SJR: 0.164, CiteScore: 0)
South African J. of Art History     Full-text available via subscription   (Followers: 2)
South African J. of Chemistry     Open Access   (Followers: 3, SJR: 0.216, CiteScore: 1)
South African J. of Criminal Justice     Full-text available via subscription  
South African J. of Cultural History     Full-text available via subscription   (Followers: 1)
South African J. of Diabetes and Vascular Disease     Full-text available via subscription   (Followers: 1)
South African J. of Economic History     Full-text available via subscription   (Followers: 2)
South African J. of Education     Open Access   (Followers: 2, SJR: 0.416, CiteScore: 1)
South African J. of Higher Education     Full-text available via subscription   (Followers: 5)
South African J. of Labour Relations     Full-text available via subscription   (Followers: 2)
South African J. of Sports Medicine     Open Access   (Followers: 8)
South African J. of Wildlife Research     Open Access   (Followers: 1)
South African J. on Human Rights     Full-text available via subscription   (Followers: 10, SJR: 0.117, CiteScore: 0)
South African Music Studies : SAMUS     Full-text available via subscription   (Followers: 2)
South African Ophthalmology J.     Full-text available via subscription  
South African Pharmaceutical and Cosmetic Review     Full-text available via subscription  
South African Radiographer     Full-text available via subscription  
Southern African Business Review     Open Access  
Southern African Forestry J.     Full-text available via subscription   (Followers: 1)
Southern African Humanities     Full-text available via subscription   (Followers: 2, SJR: 0.659, CiteScore: 1)
Southern African J. of Accountability and Auditing Research     Full-text available via subscription  
Southern African Review of Education with Education with Production     Full-text available via subscription   (Followers: 2)
Stilet : Tydskrif van die Afrikaanse Letterkundevereniging     Full-text available via subscription   (Followers: 1)
Studies in Economics and Econometrics     Full-text available via subscription   (Followers: 4, SJR: 0.11, CiteScore: 0)
Suid-Afrikaanse Tydskrif vir Natuurwetenskap en Tegnologie     Open Access   (Followers: 1)
Tax Breaks Newsletter     Full-text available via subscription   (Followers: 5)
TAXtalk     Full-text available via subscription   (Followers: 5)
The Dairy Mail     Full-text available via subscription   (Followers: 2)
Transport World Africa     Full-text available via subscription   (Followers: 2)
Unisa Latin American Report     Full-text available via subscription  
Veld & Flora     Full-text available via subscription   (Followers: 1)
Water & Sanitation Africa     Full-text available via subscription   (Followers: 3)
Without Prejudice     Full-text available via subscription  
Word and Action = Woord en Daad     Full-text available via subscription  

              [Sort by number of followers]   [Restore default list]

Journal Cover
South African Journal of Chemistry
Journal Prestige (SJR): 0.216
Citation Impact (citeScore): 1
Number of Followers: 3  

  This is an Open Access Journal Open Access journal
ISSN (Print) 0379-4350
Published by Sabinet Online Ltd Homepage  [184 journals]
  • Synthesis, characterization and biocompatibility of a multifunctional gold
           nanoparticle system for the delivery of single-stranded RNA to lymphocytes
           

    • Authors: Raveen Parboosing; Thavendran Govender, Glenn E.M. Maguire Hendrik G. Kruger
      Abstract: The use of RNA macromolecules as therapeutic agents for HIV and other infectious diseases is promising but limited bysuboptimal delivery to the target site. With HIV infection, this is particularly challenging since lymphocytes are particularlydifficult to transfect. This paper describes an innovative strategy for the intracellular delivery of a novel single-stranded RNA(oligoribonucleotide) with putative anti-HIV activity. This strategy is based on a PEGylated gold nanoparticle scaffold covalentlylinked to the thiol-modified oligoribonucleotide via a cleavable N-succinimidyl 3-(2-pyridyldithio) propionate (SPDP) linkermolecule. The nanoparticle was then coated with a cationic polymer (polyethyleneimine) to facilitate cell entry and endosomalescape. A synthetic anti-CD4 cyclic targeting peptide was attached to the polyethyleneimine-coated nanoparticle via an SPDPlinker molecule, in an attempt to enhance uptake and selectivity. Synthesis, characterization, SPDP and RNA loading,cytotoxicity and antiviral activity of the nanoparticle are described. Approximately 45 000 strands of RNA were taken up perlymphocyte. Uptake was limited by relatively inefficient loading ofRNAonto the gold nanoparticle surface (1 strand per 4.8 nm2of nanoparticle surface area) and significant aggregation of the nanoparticle in physiological solutions. No antiviral activity wasdemonstrated, possibly due to insufficient intracytoplasmic delivery of the RNA.
      PubDate: 2018-01-01T00:00:00Z
       
  • Performance of Mn2+-modified bentonite clay for the removal of fluoride
           from aqueous solution

    • Authors: Rabelani Mudzielwana; Mugera W. Gitari, Segun A. Akinyemi Titus A.M. Msagati
      Abstract: A low-cost adsorbent produced from Mn2+-modified bentonite clay was evaluated for groundwater defluoridation. Batch experimentswere used to evaluate the effect of contact time at various adsorbent dosages, adsorption isotherms and the effect of pH onfluoride removal. The results showed that the optimum F– uptake occurred within the first 30 min contact time and the percentageremoval increased with increasing adsorbent dosage. The data fitted better to pseudo-second-order reaction indicating that F–adsorption occurred via chemisorption. The Weber-Morris model of intra-particle diffusion revealed that both surface andintra-particle diffusion processes were involved during the F– adsorption process. Furthermore, the batch results showed thatpH of the solution governed the percentage of fluoride removal with the optimum of 75.2 % fluoride removal achieved at pH 4.The adsorbent chemical stability assessment showed that chemical species were leached at trace concentrations which arewithin the South African National Standards (SANS) limits. Electrostatic attraction and ion-exchange were established as themajor mechanisms responsible for fluoride adsorption at acidic pH and at moderate to alkaline pH levels, respectively. The studydemonstrated that Mn2+ intercalated bentonite clay has potential for application in defluoridation of groundwater.
      PubDate: 2018-01-01T00:00:00Z
       
  • A validated method for the detection and quantitation of synthetic
           cannabinoids in whole blood and urine, and its application to postmortem
           cases in Johannesburg, South Africa

    • Authors: Dale Pon; Ildiko J. Fenyvesi
      Abstract: A LC-HRMS (liquid chromatography coupled with high resolution mass spectrometry) method for the detection andquantitation of several synthetic cannabinoids (JWH-018, JWH-019, JWH-073, JWH-081, JWH-122 JWH-200, JWH-250, AM-2201,(±)-CP 47,497, (C8)-CP 47,497, HU-211) and selected metabolites (JWH-018 N-(4-hydroxypentyl) and JWH-073N-(3-hydroxybutyl)) in whole blood and urine was developed and validated. These methods were applied to postmortem casesfrom the Johannesburg Forensic Pathology Services Medicolegal Laboratory (FPS-MLL) to assess the prevalence of thesesynthetic cannabinoids amongst the local postmortem population. Urine samples were extracted utilizing a solid phase extraction(SPE) method, while blood samples were extracted utilizing liquid-liquid extraction (LLE) method. The accuracy of the analytesranged from 88–107 % in whole blood (relative standard deviation (RSD) = 7.5–15.0 %), and from 95–109 % in urine (RSD =4.9–11.9 %). The limits of detection (LOD) and the limits of quantitation (LOQ) for the analytes ranged between 0.675 ng mL–1 and3.375 ng mL–1 in whole blood, and between 0.225 ng mL–1 to 3.375 ng mL–1 in urine. None of the postmortem cases tested positive forany of the targeted analytes. The sample population could be extended to living subjects such as those in drug rehabilitationcentres or in hospitals to obtain a more accurate representation of the overall usage in South Africa.
      PubDate: 2018-01-01T00:00:00Z
       
  • Anti-corrosion properties of areca palm leaf extract on aluminium in 0.5 M
           HCl environment

    • Authors: Narasimha Raghavendra; Jathi Ishwara Bhat
      Abstract: The aluminium corrosion inhibition behaviour in the presence of Areca palm leaves (AL) extract in hydrochloric acid (0.5 M) medium was examined by chemical (mass loss), AC impedance spectroscopy, potentiodynamic polarization and surface (scanning electron microscopy) methods. Aluminium protection rates increased with an increase in the amount of AL extract to the 0.5 M HCl system and decreased with increasing in the contact time of aluminium metal and temperature of 0.5 M HCl solution. Arrhenius equation was applied in the determination of activation energy values. The other activation parameters such as activation entropy and enthalpy values were obtained from the transition state plot. The adsorption of AL extract species on the Al surface in 0.5 M HCl solution follows the Langmuir adsorption mechanism. Tafel curves reflect the mixed (both anodic and cathodic) inhibition behaviour of green inhibitor (AL extract species) on electrode surface (Al) in 0.5 M system. Impedance method indicates that the Al dissolution in hydrochloric acid environment was fully hindered by charge transfer process. The Al surface morphology was examined by applying scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques.
      PubDate: 2018-01-01T00:00:00Z
       
  • Flow injection spectrophotometric determination of glyphosate herbicide in
           wheat grains via condensation reaction with p-dimethylaminobenzaldehyde

    • Authors: Muhammad Rasul Jan; Jasmin Shah, Mian Muhammad Behisht Ara
      Abstract: A fast and sensitive method was developed for determination of glyphosate, using flow injection analysis. The analyte was convertedto a photoactive product that shows maximum absorbance at 405 nm. Beer’s law was obeyed over a range of 0.7–20 μg mL–1.The limit of detection and quantification were found to be 0.20±0.01 and 0.70±0.02 μg mL–1 with a high sample throughput of 60samples h–1. The investigation of interference effect shows that among the compounds studied, only aminomethyl phosphonicacid exhibits a signal enhancing effect when present in higher concentration ratio with the analyte and this can be assumed to be alimitation of the present method. The percentage recoveries and residue of glyphosate in wheat grains samples, were found in therange of 90.0 ± 0.6 % to 93.0 ± 0.6 % and 1.13 ± 0.009 μg g–1, respectively.
      PubDate: 2018-01-01T00:00:00Z
       
  • Hydrazide derivatives : an overview of their inhibition activity against
           acid corrosion of mild steel

    • Authors: Prakash Shetty
      Abstract: This paper gives an overview of the application of hydrazide derivatives in acid media as corrosion inhibitors of mild steel.In chemical and petrochemical industries, mild steel is the major constructional material widely used. Acid solutions havebeen commonly used in these industries as pickling agents to remove rust or any scale from the mild steel surface. The excessivedissolution of mild steel in such aggressive medium can be best controlled by addition of suitable organic inhibitors. Hydrazidederivatives are widely used in such applications as mild steel corrosion inhibitors. The various factors which influence thecorrosion inhibition efficiency of different hydrazide derivatives have been discussed. The information provided is useful forvarious industries where corrosion inhibitors are needed to protect mild steel structures which are being exposed to hydrochloricor sulphuric acid solutions.
      PubDate: 2018-01-01T00:00:00Z
       
  • Optimization and electrochemical study on the control of mild steel
           corrosion in hydrochloric acid solution with bitter kola leaf extract as
           inhibitor

    • Authors: V.C. Anadebe; O.D. Onukwuli, M. Omotioma N.A. Okafor
      Abstract: Response surface methodology was applied to predict the optimum control of mild steel corrosion in acid medium withbitter kola leaf extract as inhibitor. The experiment was carried out to investigate the mutual interactions between the consideredindependent variables and the expected responses. Thermometric, gravimetric, potentiodynamics polarization and electrochemicalimpedance spectroscopy were used in the corrosion inhibition study. As a supplementary technique, infrared spectroscopywas used to analyze the pure extract and corrosion products and it was observed that some peaks shifted while some disappeared.Inhibition efficiencies of 88.24 %, 86.81 %, 90 %, 89.5 % and 85.3 % were obtained from optimization, thermometric, gravimetric,potentiodynamics polarization and electrochemical impedance spectroscopic techniques, respectively. The bitter kola leafextract behaved as a mixed-mode inhibitor. Application of response surface methodology in this study was found to be good inpredicting the optimum range for controlling of metal corrosion thereby reducing the number of experimental runs.
      PubDate: 2018-01-01T00:00:00Z
       
  • The role of Brønsted and Lewis acidity in the green synthesis of
           homopropargyl alcohols over HZSM-5

    • Authors: Balaga Viswanadham; Sooboo Singh, Holger B. Friedrich Abdul S. Mahomed
      Abstract: A highly efficient and simple reaction under exceptionally mild conditions is shown for the synthesis of biologically and pharmaceuticallyactive molecules of homopropargyl alcohol using HZSM-5 as the catalyst. Products analyzed by IR, 1H NMR,13CNMR and GC-MS showed consistent yields of 98 % of the alcohol, even with respective recycles of the regenerated catalyst.The reaction was also carried out with selected mineral acids, acidic oxides and other acidic catalysts to compare reactivity and theinfluence of the type of acidity involved in the reaction. The results indicate that the presence of both Brønsted and Lewis acidityis beneficial for inducing a high rate of reaction when compared to systems having either predominantly Brønsted or Lewisacidity.
      PubDate: 2018-01-01T00:00:00Z
       
  • The effect of synthesis method on the structure, and magnetic and
           photocatalytic properties of hematite (α-Fe2O3) nanoparticles

    • Authors: Ibrahim Abdulkadir; Hafiz M.I. Abdallah, Sreekantha B. Jonnalagadda Bice S. Martincigh
      Abstract: Samples of hematite (α-Fe2O3) nanoparticles have been synthesized through the co-precipitation route in cetyltrimethyl-ammonium bromide(Hem_PR), via a citric acid sol-gel method (Hem_SG) and a modified sol-gel method in Tween 20 (Hem_TW),and each were annealed at three different temperatures (400, 500 and 600 °C). The samples were characterized by X-ray diffraction(XRD), Fourier transform infrared spectroscopy (FTIR), transmission and high-resolution electron microscopy (TEM andHRTEM), Mössbauer spectroscopy and by means of a vibrating sample magnetometer (VSM). In addition, the photocatalyticbehaviour of each sample was tested on the degradation of rhodamine B (RhB) in solution. All the characterization techniquesshowed the formation of phases of pure hematite nanoparticles with improved crystallinity after higher temperature annealing.However, the nanoparticles synthesized in Tween 20 showed the smallest particle size and highest BET surface area, saturationmagnetization and photocatalytic activity. Of particular note was the ability of Tween 20 to control the growth of the particles sothat grain sizes well below 10 nm were obtained. Thus, Tween 20, when used as a surfactant in the sol-gel route, can serve toimprove the physical properties of synthesized hematite nanoparticles.
      PubDate: 2018-01-01T00:00:00Z
       
  • Simultaneous determination of nitrate, nitrite and phosphate in
           environmental samples by high performance liquid chromatography with UV
           detection

    • Authors: Mohau N. Moshoeshoe; Veronica Obuseng
      Abstract: An HPLC method using an UV detector was developed for the simultaneous determination of nitrites, nitrates and phosphates inenvironmental samples. Chromatographic separation was achieved isocratically on a Phenomenex Synergi Polar-RP LC columnusing acetonitrile and acidified water (pH 2.7) at 60:40 v/v as mobile phase. Baseline resolution of all the three analytes wasachieved within 3 min. The developed method was applied to water samples obtained from the wastewater treatment plant inGaborone, Botswana. The use of HPLC technique in this study demonstrated its ability to carry out a simultaneous determinationof NO2–, NO3– and PO43– in water samples. The treatment plant was found to be functioning within expectations, removing 97.6%NO2–, 88.0% NO3– and 90.9% PO43– from the received wastewater. Results of the developed method were comparable with those ofthe traditional ion chromatography method, showing accuracy values between 95.22% and 98.04 %. The precision of the methodfor the determination of all analytes was determined by RSD values, all of which were lower than 5%. The method is of low cost,fast, has an easy procedure and avoids the use of many reagents – some of which may be hazardous.
      PubDate: 2018-01-01T00:00:00Z
       
  • Determination of dichlorodiphenyltrichloroethane (DDT) and metabolites
           residues in fish species from Eastern Lake Tanganyika

    • Authors: John A.M. Mahugija; Lutamyo Nambela Aviti J. Mmochi
      Abstract: In this study, the levels and status of dichlorodiphenyltrichloroethane (DDT) residues in fish samples collected from EasternLake Tanganyika were investigated. The analytes were determined using gas chromatography equipped with an electron capturedetector (GC–ECD) and by gas chromatography-mass spectrometry (GC-MS). The compounds p,p’-DDE (4,4’-DDE), p,p’-DDD(4,4’-DDD), o,p’-DDT (2,4’-DDT) and p,p’-DDT (4,4’-DDT) were detected in all the samples, with total DDT concentrationsranging from 23 ± 8.3 to 339 ± 27 μg kg–1 fresh weight and 1736 ± 1388 μg kg–1 to 25 552 ± 4241 μg kg–1 lipid weight. The highestconcentrations of total DDT were detected in Lates stappersii species. The ratios of the metabolites (DDD + DDE) to the parentcompound (p,p’-DDT) were low (< 1) in all the fish samples, indicating exposure to fresh DDT. The concentrations of the DDTresidues exceeded the extraneous maximum residue limit of 1.0 μg kg–1, indicating risks and concerns for public health and theenvironment because of the indication of fresh application of banned pesticides and bioaccumulation. There is need for continuedmonitoring of the residues in Lake Tanganyika environs and controlling the pesticides used in the area.
      PubDate: 2018-01-01T00:00:00Z
       
  • Fabrication of nitrogen donor macro- and meso-porous materials for group
           11 metal ions sorption

    • Authors: Kelebohile Mphanje; Orpah Zinyemba James Darkwa
      Abstract: Macro(meso) porous polymer materials were prepared via a modified TIPS method using reagent grade polymers mixtures;polyacrylonitrile (PAN) and polyvinylpyridine-co-styrene (PVPS). Reaction conditions such as concentration, temperature andthe solvents used were found to affect the morphology of the polymer materials formed. The use of low heat for polymer dissolution,near critical point polymer concentration and a miscible solvent/non-solvent pair in excess non-solvent were found toproduce porous polymers. The macro-(meso-) porous materials were further used in metal adsorption/desorption studies andthey were found to remove up to 80 % of Cu(II), Ag(I) and Au(III) from aqueous solution. Adsorption/desorption experimentswere performed using the polymer monolith KSP1{(PAN : PVPS = 75 : 25 (w/w) in DMSO : H2O = 90 : 10(v/v)} and it showedexcellent reusability adsorbing and desorbing up to 90 % of the metal ions in a series of five cycles. Ternary solutions for adsorption/desorption experiments were added in the order Cu(II), Ag(I) and Au(III).
      PubDate: 2018-01-01T00:00:00Z
       
  • Effects of zinc precursor, basicity and temperature on the aqueous
           synthesis of ZnO nanocrystals

    • Authors: Maroua Mrad; Bilel Chouchene Tahar Ben Chaabane
      Abstract: The effects of the zinc salt precursors, the reaction temperature and the alkaline ratio b (b = [OH-]/[Zn2+]) on the aqueoussynthesis of ZnO nanocrystals were investigated. Depending on the type of the zinc precursor, Zn5(OH)8Cl2·H2O orZn5(OH)8(NO3)2.2H2O lamellar phases were obtained at room temperature (20 °C) when the alkaline ratio is lower (0.5 ≤ b ≤ 1,6 ≤ pH ≤ 6.4). When the reaction temperature increased to 95 °C, zinc hydroxide chloride monohydrate was obtained in one casewhereas zinc oxide was formed in the other, and no lamellar phase of Zn5(OH)8(NO3)2.2H2O was obtained. Thermal decompositionof the two lamellar phases was carried out and mainly showed that Zn5(OH)8(NO3)2.2H2O was completely decomposed toZnO when the annealed temperature reached ~250 °C while Zn5(OH)8Cl2·H2O was totally transformed to ZnO at about 400 °C, ahigher comparative temperature that confirms the better thermal stability of the zinc hydroxide chloride monohydrate.
      PubDate: 2018-01-01T00:00:00Z
       
  • Hyphenated LC-ICP-MS/ESI-MS identification of halogenated metabolites in
           South African marine ascidian extracts

    • Authors: Candice L. Bromley; Andrea Raab, Shirley Parker-Nance, Denzil R. Beukes, Marcel Jaspars Michael T. Davies-Coleman
      Abstract: Extracts of 13 species of marine ascidian collected in Algoa Bay were analyzed by LC-ICP-MS/ESI-MS. This technique allowsparallel analysis of the molecular species and the presence of certain elements. The LC-ICP-MS/ESI-MS technique was used totarget iodinated metabolites in this study. Three ascidian species afforded the known 3,5–diiodo-4-methoxyphenethylamine(12), which was confirmed by the isolation of this metabolite from Aplidium monile. MS also suggested the presence of the known3,5–dibromo-4-methoxyphenethylamine (10) and the new 3-bromo-5–iodo-4-methoxyphenethylamine (11) in the A. monileextract. The presence of the known 3,5-dibromotetramethyltyrosine (21) and the new 3-iodotetramethyltyrosine (23) in extractsof an unidentified Didemnum species was similarly proposed from MS evidence. This is the first report of the occurrence ofiodinated metabolites in South African marine invertebrates.
      PubDate: 2018-01-01T00:00:00Z
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
Home (Search)
Subjects A-Z
Publishers A-Z
Customise
APIs
Your IP address: 54.144.100.123
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-