Search results

The purpose of this study is to investigate the tribological performance (anti-friction and anti-wear properties) of commercial Mobil grade lubricants used in a journal bearing system in a power plant.

Three grades of Mobil lubricants (DTE 24, DTE 25 and DTE 26) are considered during the study. Titanium dioxide nanoparticles (TiO₂, 0.5 Wt.%) of size 40 nm are used as a lubricant additive to examine the performance of the lubricants. The viscosity of the lubricant is computed using modified Krieger–Dougherty viscosity model. The morphology of TiO₂ nanoparticles is studied with the help of scanning electron microscopy, ultra violet spectrophotometer and X-ray diffraction. The study of antifriction and antiwear properties for lubricants is carried out on four-ball tribo-tester for operating conditions specified by ASTM standards.

The tribochemical reaction film is formed between ball surfaces during the experiments on four-ball tester that minimizes the asperity contact due to addition of TiO₂ nanoparticles in the lubricant. The viscosity of the lubricant is enhanced due to the addition of TiO₂ nanoparticles. The frictional coefficient and wear scar diameters of balls in the lubricants are reduced in the range of 6-26 and 2-7 per cent, respectively.

The tribological properties of TiO₂ as a lubricant additive in three commercial Mobil grade lubricants are investigated in this paper. The results obtained in this paper are expected to be helpful to bearing designers, researchers and academicians concerned with the relevant study.

An increased environmental awareness of health hazards caused by synthetic dyes has led to revival of natural dyes. Dyes obtained from natural sources have emerged as important substitutes for synthetic dyes. Color-yielding plants such as butterfly pea flowers have been used to study color extraction and can be used as dyeing material for coloring industry. Analytical studies, such as UV–VIS spectrophotometer analysis and dye concentration analysis, are performed on extracted dye using flower petals. In this study, aqueous extractions of dye from flowers were carried out in the following conditions to obtain optimization characterization: time of extraction (30-180 minutes), temperature (60-90°C), amount of flowers (0.1-2gm) and pH (2-10). It was observed that dye concentration increases gradually at higher temperature and for longer time.

The purpose of this paper is to investigate the effect of boric acid as a flux on the formation of the akermanite phase and optical properties of SrMgSi₂O₇:Eu,Dy phosphors.

The silicate‐based phosphor is prepared by sol‐gel method. Sr(NO₃)₂, Mg(NO₃)₂ · 6H₂O, Dy₂O₃, Eu₂O₃, are added to distilled water in their stoichiometric ratio, the obtained solution are mixed with H₃BO₃ (in the range of 0.01‐0.5 mol%) and a polymeric compound TESO (C₈H₂O₄Si). At the end, the phase composition and optical properties are investigated using X‐ray diffraction (XRD) and spectrophotometer analysis, respectively.

The XRD results showed that the akermanite (Sr₂MgSi₂O₇) is the only crystalline phase which is detected in the sample containing 0.05 mol% boric acid. Increasing of boric acid does not have a great effect on the XRD patterns intensity. Spectrophotometer analysis results show three maximum at 365, 395 and 430 nm on the excitation spectra. It also shows intensity of the excitation and emission spectra increased by adding boric acid up to 0.25 mol% and a sudden drop at 0.5 mol% boric acid.

Using boric acid as a flux, enhances formation of akermanite phase at lower temperature with desirable optical properties and a cost‐benefit way for industrial production. In this research, optimum value of boric acid was determined using XRD data, emission and excitation spectra.

The purpose of this paper is to investigate the efficacy of bacterial exopolysaccharides (Eps) in reactive black 5 (RB5) textile dye wastewater bioremediation.

The Eps were produced by bacteria isolated from cotton gin trash soils collected from different cotton-growing regions in Kenya for comparison purposes. A broth medium reconstituted using molasses was assessed for its capacity to produce the Eps. RB5 textile dye wastewater was optimized for dye removal under different temperatures, times and molasses concentrations. Dye removal was studied by Lovibond-Day Light Comparator, UV–Vis spectrophotometer and FTIR.

It was found that cotton gin trash soils contained Eps-producing bacteria. Three of the Eps studied were found to have the capacity to remove at least 80% of the dye from the wastewater.

This research did not assess the efficacy of the RB5 dye removal from the wastewater by mixtures of the Eps.

Bioremediation of textile dye wastewater with Eps produced by bacteria cultured from cotton gin trash soil is significant because it will offer an effective and cleaner alternative to the chemical coagulants.

Alternative treatment of textile wastewater with the Eps would result in safer water being released into the water bodies as opposed to the chemically treated wastewater that contains remnant chemicals.

Research on the use of Eps produced by bacteria isolated from cotton gin trash soils for removal of RB5 dye from textile wastewater has not been done before.

To review the innovative products of a particular UK company.

Looks at the history and philosophy of the company, the design and advantages of their brand authenticator product, and then presents their latest spectrophotometric instruments.

Starting in the field of miniature spectrophotometers, which soon became very competitive, the company found a niche market and developed an instrument well‐suited to that market. Their latest products build on that success.

An encouraging report for technologists and entrepreneurs.

This study aims to determine the appropriate irradiation dose for induction of somaclonal variation in mass of unorganized parenchyma cells derived from sainfoin (Onobrychis viciifolia) tissues.

To investigate the feasibility of UV-B irradiation (312 nm), seeds and callus of sainfoin were exposed to five different intensities (20-100 per cent) for evaluating the effectiveness of phytochemical constituents and cellular behaviour.

Although percentage of seed viability reduced in 20 per cent intensity of UV-B irradiation compared with control seeds, the germination speed significantly enhanced from 3.58 to 5.42. The spectrophotometer analysis confirmed that concentrations of chlorophyll (a and b) decreased after UV-B exposure as compared with control callus. Also, carotenoid content showed significant differences among treated calli. Flavonoid and phenolic contents were observed to gradually increase when the non-irradiated callus subjected to 40 and 60 per cent intensities of UV-B irradiation, respectively. Observation on cellular behaviour such as determination of nuclear and cell areas, mitotic index and chromosomal aberrations were also detected to change in different intensities of UV-B irradiation. Fragmented and aneuploidy aberrations were only observed in exposed cells with more than 40 per cent intensity of UV-B irradiation.

In reality, radiocytological evaluation was proven to be essential in deducing the effectiveness of UV-B irradiation to induce somaclonal variation in callus tissue of sainfoin.

Peanut skins are an agro-waste product with no commercial value. The purpose of this paper is to evaluate peanut skin as a natural dyestuff and to determine if this natural dye could be used in the dyeing of some Egyptian cotton cultivars.

The methodology consists of several steps; dye extraction procedure from peanut skin through aqueous extraction, then dyeing optimized using simultaneous mordanting using alum. Finally, dyed cotton has been subjected to different textile laboratory tests, for example, color measurements and mechanical properties. Color-fastness was determined on Egyptian cotton fabric. The peanut skin as a source of natural dye and the dyed cotton sample were characterized by fourier transform infrared spectroscopy (FTIR) analysis.

It was found that the natural dye extracted from peanut skin has an affinity for cotton samples and showed high dyeability with a unique color shade, good color strength and very good fastness.

The novelty of this paper is the extraction of color from the peanut's outer skin which is discarded as waste such as agro-waste of the agricultural process which can be used as a natural dye in the textile industry and applied to dyeing some Egyptian cotton fibers from different genotypes.

The aim of this study was to prepare antibacterial capsules and transfer them to cotton fabrics using the impregnation method.

For this purpose, helichrysum oil was encapsulated by ß-cyclodextrin (ß-CD) using the kneading method at three different molar ratios. The products were then applied to 100% cotton fabric through the impregnation method.

Morphological assessment showed that the inclusion complex had smooth surfaces and spherical shapes. Fourier transform infrared spectroscopy and differential scanning calorimeter analysis results confirmed the formation of the inclusion complex between ß-CD and the active agent at mole ratios of 1:1, 1:2 and 1:3 for helichrysum oil. According to the analyses, it was determined that the highest complexing rate was between 9.72% and 1:2 in capsules containing ß-CD:helichrysum oil and the sizes of particles which is 1:2 are determined to be between 2 and 25 µm. The presence of capsules on the fabrics was determined after 5 washing cycles. Antibacterial activity was evaluated against Staphylococcus aureus and Escherichia coli bacteria. The antibacterial analysis results showed that the inclusion complex provided a reduction of over 96% against both S. aureus and E. coli bacteria, and the fabrics exhibited antibacterial effects even after 5 washing cycles. The major constituents of the oil were decreased after 5 washes, but significant peaks were remained according to the gas chromatography analyses. These results indicate that helichrysum oil can be used for its antibacterial properties, and it has been observed that this activity continues up to 5 washes when transferred to the fabric in the form of an inclusion complex.

Although helichrysum oil is widely used in cosmetics, there is a lack of studies on its application in textiles. Therefore, this study investigated the potential use of helichrysum oil, which has a wide range of applications, in textiles for its antibacterial properties through molecular encapsulation. The use of naturally sourced substances such as helichrysum oil in the textile industry can offer an environmental and sustainable alternative. This study can be considered as a step toward the development of innovative and naturally sourced antibacterial products in the textile industry.

Production of oil from Camelina sativa seed (CS) by pressing yields a by‐product in the form of press cakes (PC). The PC were traditionally used as ingredient in fodder for animals. This paper aims to estimate the nutritional value of CS and PC with regard to exploitation in human nutrition.

Seed samples for analyses were collected from remote locations in Europe and in Scandinavia. The analyses of CS for the content of carbohydrates, vitamins and minerals were carried out using advanced analytical technology. With few exceptions, standard analytical methods were used.

The analyses quantified the content of carbohydrates, vitamins and minerals of CS. The mean content of glucose was 0.42 per cent, fructose 0.04 per cent, sucrose 5.5 per cent, raffinose 0.64 per cent, stachyose 0.36 per cent, starch 1.21 per cent, pectin 0.96 per cent, mucilage 6.7 per cent, crude fibre 12.8 per cent and lignin was 7.4 per cent. The analyses for vitamins were restricted to water soluble vitamins of B series. The content of thiamin (B1) was 18.8  μg/g, riboflavin (B2) 4.4  μg/g, niacin (B3) 194  μg/g, pantothenic acid (B5) 11.3  μg/g, pyridoxine (B6) 1.9  μg/g, biotin (B7) 1.0  μg/g and folate (B9) 3.2  μg/g. Analyses for selected minerals disclosed the content of calcium (Ca) 1.0 per cent, magnesium (Mg) 0.51 per cent, sodium (Na) 0.06 per cent, potassium (K) 1.6 per cent, chlorine (Cl) 0.04 per cent, phosphorus (P) 1.4 per cent, sulphur (S) 0.24 per cent, iron (Fe) 329  μg/g, copper (Cu) 9.9  μg/g, manganese (Mn) 40  μg/g, nickel (Ni) 1.9  μg/g and zinc (Zn) 69  μg/g.

The available scientific documentation does not provide information concerning analyses of CS for the content of carbohydrates, vitamins and minerals. The present investigation reveals the quantitative contribution of these substances to the total nutritional value of CS. Chemical characteristics and the role of the respective substances in metabolism are briefly reviewed.

The aim was to prepare antibacterial microcapsules and transferred to denim and non-denim (canvas) trousers.

For this purpose, lavender and sweet almond oil as active agents were encapsulated with ethylcellulose shell with a spray dryer method and carried out capsule optimization studies.

The particle diameter of the capsules ranged between 0.61 and 8.76 µm, SPAN value was 1.608 and the mean particle size was 4 µm. The mass yields of capsules ranged between 35.0 and 75.4 %w/w. Denim fabrics were treated with prepared capsules by exhaustion and spraying methods. It was seen that microcapsules provided a reduction of bacteria by over 97% against both Staphylococcus aureus and Escherichia coli and the fabrics still showed an antibacterial effect after five washing cycles.

When application methods were compared, the spraying method was found to be more sustainable process than exhaustion and could be used as an alternative for reducing energy consumption and capsules could provide antibacterial properties to the fabrics.