Chemistry Research Papers/Topics

Physico-Chemical Properties of Biodiesel from Jatropha and Castor Oils

Abstract - Biodiesel is becoming prominent among the alternatives to conventional petro-diesel due to economic, environmental and social factors. The quality of biodiesel is influenced by the nature of feedstock and the production processes employed. High amounts of free fatty acids (FFA) in the feedstock are known to be detrimental to the quality of biodiesel. In addition, oils with compounds containing hydroxyl groups possess high viscosity due to hydrogen bonding. American Standards and Te...

Prevalence And Factors Associated With Continual Opioid Use Among Patients Attending Methadone Clinic At Mwananyamala Hospital, Dar Es Salaam, Tanzania

A B S T R A C T Trends of continual drug use while under treatment have been reported worldwide. This paper assesses opioid use among patients receiving treatment in a methadone clinic for opioid addiction. A total of 126 urine samples were analyzed using LC–MS/FTMS. About 16% of patients were found to have a high prevalence level of opioids use. Prevalence level was significantly associated with the duration of treatment (p= 0.0121) and age (p =0.0328). About 125/126 patients were found t...

Efect of Nano-SiO2, Nano-TiO2 and Nano-Al2O3 Addition on Fluid Loss in Oil-Well Cement Slurry

Abstract  In this article, incorporation of nano-SiO2 (NS), nano-TiO2 (NT) and nano-Al2O3 (NA) particles and their binary and ternary blends on water fltration in oil-well cement slurry was examined. The nanoparticle contents were chosen at proportions corresponding to 1, 2, 3 and 4% based on the weight of cement. The experimental specimens were tested at three various temperatures of 70, 80 and 90 °C using a gas pressure of 1000 psi. The quantity of water fltrate collected was measured in ...

Anhydrous Monoalkylguanidines in Aprotic and Nonpolar Solvents: Models for Deprotonated Arginine Side Chains in Membrane Environments

ABSTRACT: In this study, the synthesis of crystalline dodecylguanidine free base and its spectroscopic characterization in nonpolar environments are described. IR as well as 1 H and 15N NMR spectra of the free base dissolved in aprotic solvents are substantially different from the previously reported spectra of arginine, or other monoalkylguanidinium compounds, at high hydroxide concentrations. The current results provide improved modelling for the spectroscopic signals that would be expecte...

Producing Sulphuric Acid In Tanzania And Potential Sources: A Review

Abstract Sulphuric acid is a backbone of chemical industry, agriculture and energy sectors. Tanzania has potential sources of producing its own sulphuric acid. The three most common methods: contact process, wet process and lead chamber process of producing sulphuric acid are reviewed. A modified lead chamber method can be a preferred method of producing the mineral acid by using local available raw materials according to Tanzania environment. Among of raw materials, pyrites from Samena area...

Phytochemical and Antimicrobial Properties of African peach (Sacocefalus latifolius)

Abstract This study includes phytochemical screening, quantification of secondary metabolites, thin-layer chromatography (TLC) and antimicrobial  assay of African peach (Sarcocephalus latifolius). The phytochemical analysis revealed the presence of alkaloid, flavonoid and saponin at various  quantities with saponin more abundant amongst others like tannin, glycoside and phenols that are present. All the extracts were tested for  antimicrobial activity with ethanol extract and water extract...

Phytochemical and Antimicrobial Properties of Lavandula angustifolia

Abstract: This present study deals with the quantitative and qualitative phytochemical  screening, the antimicrobial properties and thin layer chromatography of Lavandula angustifolia leaves extracts. These were achieved using the cold maceration method of  extraction involving hexane, water (aqueous) and ethanol, to ensure that a wide polarity  range of components are extracted. Alkaloid, phenol, flavonoids, tannins, terpenes,  glycosides and steroids were observed present in the leaves ...

Quantum chemical calculations on SiF4 and it's protonated analogues

Abstract: For every heteronuclear molecule, protonation can occur at more than one site  thus giving rise to more than one proton affinity. Experimentally, only one proton affinity  (PA) value is reported for a molecule and the experiment does not specify the site for the  protonation. In the present work, quantum chemical calculations are carried out on SiF4 and  its possible protonated analogues (HF4Si+ and HSiF4 + ) by employing several computational  chemistry methods including the M...

Kinetic studies of the biosorption of lead and zinc from solution using tea fibre

Abstract: This paper presents a biobsorption study on Zn and Pb(II) from dilute aqueous  solution using tea fiber as the biosorbent. The biosorption study was carried out as a function  of contact time, initial metal ion concentration and biosorbent dosage. The residual Zn and  Pb(II) in solution were determined using atomic absorption spectrophotometer. The  biosorption was also time dependent as maximum biosorption was obtained after 10 and 20  min, for both lead and zinc respectively....

Medicinal Chemistry Comparative Phytochemical Screening on Three Growth Stages of Pennisetum Pedicellatum Trin

A comparative preliminary study on the extraction and phytochemical profile of methanolic extracts of the leave, stem and root of pennisetum pedicellatum Trin at three growth stages (i.e stage 1, stage 2, stage 3) was carried out. The extracts were analysed to determine the presence of phytochemicals in the plant. The study revealed the presence of alkaloids, flavonoids, saponins and steroids. Tanins were found only in the stems of the plants and steroids were found only in the leaves. The re...

Studies on heavy metals contents of Osun River at the pre-urban settlement and across Osogbo City, Nigeria

Heavy metals were analysed in Osun River (Nigeria) between 2017 and 2018. Concentrations of the heavy metals were in the increasing order: Fe > Zn > Cu > Mn > Pb > (Ni, Cr) > (Cd, Co). Iron made up 76% of the total heavy metals measured. Activities at Swanlux Farm (a major oil palm farm) seemed to impart on Osun River as the highest Fe concentration (2.55 mg/L) was measured near the farm. In the urban settlement, average zinc concentration was almost double (0.37 mg/L) of that found in the pr...

PHYTOCHEMICAL ANALYSIS AND ISOLATION OF COMPONENTS OF STEM-BARK OF CHRYSOPHYLLUM ALBIDUM (G.Don)

Chrysophyllum albidum (Sapotaceae) is known to possess bioactive compounds belonging to important phytochemical groups. This work aims at exploring the bioactive constituents of the stem-bark of Chrysophyllum albidum, and further investigating their phytochemical compositions. Stem bark of Chrysophyllum albidum was collected, dried, powdered and extracted with hexane for 13 hours using soxhlet extraction. This was concentrated using a rotary evaporator. Phytochemical screenings of the ext...


61 - 73 Of 73 Results