Papers by Keyword: Isolation

Abstract: Chemical industry includes a biobased materials (sector) in which some oil-derived plastics and chemicals are replaced by new or alternative products derived, at least partially, from biomass. One of these biobased products is here today - lignin, but to fulfil its societal potential it is necessary to improve their market share while making valuable contributions to climate change mitigation. Great source of lignin is by-product (waste) from paper making industry. Lignin isolated from black liquors has a big potential to be used as a component for new bioplastic compositions. Lignosulphonates and lignin are polydispersions of different large fragments from natural tree dimensional lignin present in the wood. The kraft lignin consists of large amount of sulphur which is bonded in functional groups. Content of lignin in black liquor is in range 30 - 45% what brings potential of its isolation. In this paper we characterised and precipitated lignin with two inorganic and one organic acid (nitric, hydrochloric and tartaric acid).

Abstract: Micrifibrillated cellulose (MFC) is generally can be prepared either by acid hydrolysis, chemical treatments, or by a high pressure refiner. In this study, the MFC of Resak’s hardwood waste with high degree of crystallinity has been obtained by an acid hydrolysis using mineral acid H₂SO₄. The microstructures of the MFC were characterized via X-ray diffraction (XRD) and Field emission scanning electron microscope (FESEM).

Abstract: Banana pseudostems waste is abundantly available as agro-waste and has been used in different applications. In this work, the isolation of CMNF from the pseudostems of banana plant were explored. The dried stems from the species Musa acuminata were first cleaned by soxhlet extraction, alkali treatment and bleaching. Segal method will be employed to analyze data from XRD to determine crystallinity of the CMNF. Morphology of the CMNF will be determined using FESEM. Characterizations of treated and untreated samples were compared. The comparison between those treated and untreated samples giving the information about crystallite size, crystallinity and surface morphology for each treatment.

Abstract: Some unfortunate accidents of large amount of oil hydrocarbons have been reported in Mediterranean Sea which has caused severe environmental damage to the area. To safeguard the Libyan coastline and marine ecologysince thousands of human activity such as fishing largely depends on the healthycoastal environment.Twenty crude oil-degrading bacterial isolates were obtained from oil-contaminated sites at Al Hariga Oil Terminal and Nafoora Oilfield. Based on a high growth rate in crude oil and hydrocarbon degradation efficiency, two isolates were selected from the twenty isolates for further analysis. The nucleotide sequence of 16S rRNA gene showed that these isolates are likely Pseudomonas aeruginosa andKocuriapastrius. One of the isolates is a potential Gram-negative Pseudomonas bacterium based on petroleum hydrocarbon degradation efficiency and potent emulsifying activity; thus, this isolate is identified as P. aeruginosa NAF1; the other isolate K. pastrius SAR3 is identified as a Gram-positive bacterium. Corn steep liquor (CSL) and solid waste date (SWD) were used for an in situ molasses technique to enhance bacterial growth and biodegradation efficiency. P. aeruginosa NAF1 exhibited 70% and 76% crude oil degradation in 0.2% (w/v) CSL and SWD in 28 d, respectively. Likewise, K. pastrius SAR3 yielded 68% and 70% crude oil degradation in 0.2% (w/v) CSL and SWD in 28 d, respectively.

Abstract: One application of cellulose is for the isolation of steam distribution pipe. Many researchers on cellulose for isolation have been conducted due to a popular issue of energy saving with its fairly cheap treatment cost. Cellulose is produced from imperata cylindrica reed by an extraction process. The results of extraction were in a form of cellulose fibers. To make the test easier, the cellulose fibers were made in a form of sheets by adding 3.5 % Na-CMC (Sodium Carboxyl Methyl Cellulose). The sheets are produced by blending for 30, 45, and 60 minutes and then put it into the oven with temperature of 40°C for 36 hours. Tests were conducted for four parameters, namely, density, tensile strength, elasticity modulus, and morphology. The density was measured by picnometer, while the tensile strength and elasticity modulus was measured by UCT-5T Model UTM, and the morphology was measured by optical microscope from Nikon Ephipot. The test showed : minimal and maximal densities were 166.7 kg/m³ and 550.2 kg/m³, respectively; minimal and maximal average tensile strengths were 9.16 MPa and 10.5 MPa, respectively; minimal and maximal elasticity modulus were 79.948 MPa and 113.09 MPa, respectively; and minimal and maximal specific tensile strengths were 0.01665 MPa/(kg/m³) and 0.06289 MPa/(kg/m³).

Abstract: The geosynthetic materials are extensively used in a wide range of applications in civil engineering. In this study, a nonwoven high strength geotextile which is generally utilized as a reinforcing material for earth structures and a ultrahigh molecular weight polyethylene (UHMWPE) geomembrane (generally used to seal the inner face of toxic liquid tanks against leakage) are used together beneath structures for seismic isolation purposes. The dynamic interface properties of the surface formed between these two materials have been tested on small scale models by shaking table tests. The results were impressive such that the accelerations transferred to the superstructure were significantly reduced. Also, it was observed that the materials used during the research had almost no abrasion at the end of a series of experiments which revealed that the tested materials could be used for repetitive dynamic loadings.

Abstract: Phenazines represent a group of heterocyclic nitrogen-containing compounds showing a broad spectrum of antibiotic properties. Phenazines are studied extensively for their further application in plant disease management. Pseudomonas aeruginosa produce three phenazine compounds as the secondary metabolites. These metabolites are known as phenazine-1-carboxylic acid (PCA), 2-hydroxyphenazine-1-carboxylic acid and 2-hydroxyphenazine (2-OH P). In this study separation and characterization of phenazines were done by using thin layer chromatography (TLC), column chromatography and ultraviolet (UV) spectrum. Two compounds were isolated and their concentration was identified.

Abstract: A bacteria strain for efficiently removing nitrite nitrogen was isolated and purified from sediment in shrimp pond, and the morphology of bacteria was observed using scanning electron microscopy, and the homology analysisof 16SrDNA sequence of the strain was conducted. The results showed that the strain was identified as Acinetobacter baumanii according to the morphological characteristics, physiological and biochemical characteristics and 16SrDNA sequence analysis. The isolated strain had a high heterotrophic nitrification function, the removal rate of nitrite nitrogen reached 97.17% after 12 h.

Abstract: An approach of combining the rigid body theory and improved Fourier series method is proposed to model the single-stage isolation system based on an elastic plate-shell coupled structure, and the isolation performance is investigated. Considering the practical problems of the machinery system design in the field of marine engineering, the influences of various structural parameters on the isolation performance for the isolation system is implemented. The numerical simulation results are given and discussed.

Abstract: In the ultra precision measuring and machining, precision measuring instruments and precision accuracy are not only related to the precision of the instrument itself, the vibration from the surrounding environment, and many other factors also determine the accuracy of the measurement and processing. In order to solve the micro-amplitude vibration and shock proof problem of high precision equipment, the article adopted the active vibration isolation technology to build the vibration isolation experiment system based on the pneumatic artificial muscle as the action, according to the characteristics of the vibration isolation system and performance requirements, The experiment was completed by using PID control algorithm. By comparing with passive control, the results show that the vibration isolation system has good broadband vibration isolation effect, in the low frequency, effect is remarkable. This study laid a foundation for further control of pneumatic muscle in isolation system.